]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/netinet/ip_input.c
xnu-4903.270.47.tar.gz
[apple/xnu.git] / bsd / netinet / ip_input.c
index 9dde8f80e93f811a2328efa980453d7e6a0a0a7e..35ee3066632f9b877b62490eac5e2be7520eb3fd 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2013 Apple Inc. All rights reserved.
+ * Copyright (c) 2000-2018 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
@@ -66,7 +66,7 @@
  * Version 2.0.
  */
 
-#define        _IP_VHL
+#define _IP_VHL
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <net/ntstat.h>
 #include <net/dlil.h>
 #include <net/classq/classq.h>
+#include <net/net_perf.h>
+#include <net/init.h>
 #if PF
 #include <net/pfvar.h>
 #endif /* PF */
 #include <netkey/key.h>
 #endif /* IPSEC */
 
-#define        DBG_LAYER_BEG           NETDBG_CODE(DBG_NETIP, 0)
-#define        DBG_LAYER_END           NETDBG_CODE(DBG_NETIP, 2)
-#define        DBG_FNC_IP_INPUT        NETDBG_CODE(DBG_NETIP, (2 << 8))
+#define DBG_LAYER_BEG           NETDBG_CODE(DBG_NETIP, 0)
+#define DBG_LAYER_END           NETDBG_CODE(DBG_NETIP, 2)
+#define DBG_FNC_IP_INPUT        NETDBG_CODE(DBG_NETIP, (2 << 8))
 
 #if IPSEC
 extern int ipsec_bypass;
 extern lck_mtx_t *sadb_mutex;
 
-lck_grp_t      *sadb_stat_mutex_grp;
-lck_grp_attr_t *sadb_stat_mutex_grp_attr;
-lck_attr_t     *sadb_stat_mutex_attr;
+lck_grp_t       *sadb_stat_mutex_grp;
+lck_grp_attr_t  *sadb_stat_mutex_grp_attr;
+lck_attr_t      *sadb_stat_mutex_attr;
 decl_lck_mtx_data(, sadb_stat_mutex_data);
-lck_mtx_t      *sadb_stat_mutex = &sadb_stat_mutex_data;
+lck_mtx_t       *sadb_stat_mutex = &sadb_stat_mutex_data;
 #endif /* IPSEC */
 
 MBUFQ_HEAD(fq_head);
 
-static int frag_timeout_run;           /* frag timer is scheduled to run */
+static int frag_timeout_run;            /* frag timer is scheduled to run */
 static void frag_timeout(void *);
 static void frag_sched_timeout(void);
 
 static struct ipq *ipq_alloc(int);
 static void ipq_free(struct ipq *);
 static void ipq_updateparams(void);
+static void ip_input_second_pass(struct mbuf *, struct ifnet *,
+    u_int32_t, int, int, struct ip_fw_in_args *, int);
 
 decl_lck_mtx_data(static, ipqlock);
-static lck_attr_t      *ipqlock_attr;
-static lck_grp_t       *ipqlock_grp;
-static lck_grp_attr_t  *ipqlock_grp_attr;
+static lck_attr_t       *ipqlock_attr;
+static lck_grp_t        *ipqlock_grp;
+static lck_grp_attr_t   *ipqlock_grp_attr;
 
 /* Packet reassembly stuff */
-#define        IPREASS_NHASH_LOG2      6
-#define        IPREASS_NHASH           (1 << IPREASS_NHASH_LOG2)
-#define        IPREASS_HMASK           (IPREASS_NHASH - 1)
-#define        IPREASS_HASH(x, y) \
+#define IPREASS_NHASH_LOG2      6
+#define IPREASS_NHASH           (1 << IPREASS_NHASH_LOG2)
+#define IPREASS_HMASK           (IPREASS_NHASH - 1)
+#define IPREASS_HASH(x, y) \
        (((((x) & 0xF) | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK)
 
 /* IP fragment reassembly queues (protected by ipqlock) */
 static TAILQ_HEAD(ipqhead, ipq) ipq[IPREASS_NHASH]; /* ip reassembly queues */
-static int maxnipq;                    /* max packets in reass queues */
-static u_int32_t maxfragsperpacket;    /* max frags/packet in reass queues */
-static u_int32_t nipq;                 /* # of packets in reass queues */
-static u_int32_t ipq_limit;            /* ipq allocation limit */
-static u_int32_t ipq_count;            /* current # of allocated ipq's */
+static int maxnipq;                     /* max packets in reass queues */
+static u_int32_t maxfragsperpacket;     /* max frags/packet in reass queues */
+static u_int32_t nipq;                  /* # of packets in reass queues */
+static u_int32_t ipq_limit;             /* ipq allocation limit */
+static u_int32_t ipq_count;             /* current # of allocated ipq's */
 
 static int sysctl_ipforwarding SYSCTL_HANDLER_ARGS;
 static int sysctl_maxnipq SYSCTL_HANDLER_ARGS;
 static int sysctl_maxfragsperpacket SYSCTL_HANDLER_ARGS;
 
+#if (DEBUG || DEVELOPMENT)
+static int sysctl_reset_ip_input_stats SYSCTL_HANDLER_ARGS;
+static int sysctl_ip_input_measure_bins SYSCTL_HANDLER_ARGS;
+static int sysctl_ip_input_getperf SYSCTL_HANDLER_ARGS;
+#endif /* (DEBUG || DEVELOPMENT) */
+
 int ipforwarding = 0;
 SYSCTL_PROC(_net_inet_ip, IPCTL_FORWARDING, forwarding,
-       CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &ipforwarding, 0,
-       sysctl_ipforwarding, "I", "Enable IP forwarding between interfaces");
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &ipforwarding, 0,
+    sysctl_ipforwarding, "I", "Enable IP forwarding between interfaces");
 
 static int ipsendredirects = 1; /* XXX */
 SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect,
-       CTLFLAG_RW | CTLFLAG_LOCKED, &ipsendredirects, 0,
-       "Enable sending IP redirects");
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ipsendredirects, 0,
+    "Enable sending IP redirects");
 
 int ip_defttl = IPDEFTTL;
 SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW | CTLFLAG_LOCKED,
-       &ip_defttl, 0, "Maximum TTL on IP packets");
+    &ip_defttl, 0, "Maximum TTL on IP packets");
 
 static int ip_dosourceroute = 0;
 SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute,
-       CTLFLAG_RW | CTLFLAG_LOCKED, &ip_dosourceroute, 0,
-       "Enable forwarding source routed IP packets");
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_dosourceroute, 0,
+    "Enable forwarding source routed IP packets");
 
 static int ip_acceptsourceroute = 0;
 SYSCTL_INT(_net_inet_ip, IPCTL_ACCEPTSOURCEROUTE, accept_sourceroute,
-       CTLFLAG_RW | CTLFLAG_LOCKED, &ip_acceptsourceroute, 0,
-       "Enable accepting source routed IP packets");
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_acceptsourceroute, 0,
+    "Enable accepting source routed IP packets");
 
 static int ip_sendsourcequench = 0;
 SYSCTL_INT(_net_inet_ip, OID_AUTO, sendsourcequench,
-       CTLFLAG_RW | CTLFLAG_LOCKED, &ip_sendsourcequench, 0,
-       "Enable the transmission of source quench packets");
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_sendsourcequench, 0,
+    "Enable the transmission of source quench packets");
 
 SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragpackets,
-       CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &maxnipq, 0, sysctl_maxnipq,
-       "I", "Maximum number of IPv4 fragment reassembly queue entries");
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &maxnipq, 0, sysctl_maxnipq,
+    "I", "Maximum number of IPv4 fragment reassembly queue entries");
 
 SYSCTL_UINT(_net_inet_ip, OID_AUTO, fragpackets, CTLFLAG_RD | CTLFLAG_LOCKED,
-       &nipq, 0, "Current number of IPv4 fragment reassembly queue entries");
+    &nipq, 0, "Current number of IPv4 fragment reassembly queue entries");
 
 SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragsperpacket,
-       CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &maxfragsperpacket, 0,
-       sysctl_maxfragsperpacket, "I",
-       "Maximum number of IPv4 fragments allowed per packet");
-
-int ip_doscopedroute = 1;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, scopedroute, CTLFLAG_RD | CTLFLAG_LOCKED,
-       &ip_doscopedroute, 0, "Enable IPv4 scoped routing");
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &maxfragsperpacket, 0,
+    sysctl_maxfragsperpacket, "I",
+    "Maximum number of IPv4 fragments allowed per packet");
 
 static uint32_t ip_adj_clear_hwcksum = 0;
 SYSCTL_UINT(_net_inet_ip, OID_AUTO, adj_clear_hwcksum,
-       CTLFLAG_RW | CTLFLAG_LOCKED, &ip_adj_clear_hwcksum, 0,
-       "Invalidate hwcksum info when adjusting length");
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_adj_clear_hwcksum, 0,
+    "Invalidate hwcksum info when adjusting length");
+
+static uint32_t ip_adj_partial_sum = 1;
+SYSCTL_UINT(_net_inet_ip, OID_AUTO, adj_partial_sum,
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_adj_partial_sum, 0,
+    "Perform partial sum adjustment of trailing bytes at IP layer");
 
 /*
  * XXX - Setting ip_checkinterface mostly implements the receive side of
@@ -249,7 +260,34 @@ SYSCTL_UINT(_net_inet_ip, OID_AUTO, adj_clear_hwcksum,
  */
 static int ip_checkinterface = 0;
 SYSCTL_INT(_net_inet_ip, OID_AUTO, check_interface, CTLFLAG_RW | CTLFLAG_LOCKED,
-       &ip_checkinterface, 0, "Verify packet arrives on correct interface");
+    &ip_checkinterface, 0, "Verify packet arrives on correct interface");
+
+static int ip_chaining = 1;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, rx_chaining, CTLFLAG_RW | CTLFLAG_LOCKED,
+    &ip_chaining, 1, "Do receive side ip address based chaining");
+
+static int ip_chainsz = 6;
+SYSCTL_INT(_net_inet_ip, OID_AUTO, rx_chainsz, CTLFLAG_RW | CTLFLAG_LOCKED,
+    &ip_chainsz, 1, "IP receive side max chaining");
+
+#if (DEBUG || DEVELOPMENT)
+static int ip_input_measure = 0;
+SYSCTL_PROC(_net_inet_ip, OID_AUTO, input_perf,
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+    &ip_input_measure, 0, sysctl_reset_ip_input_stats, "I", "Do time measurement");
+
+static uint64_t ip_input_measure_bins = 0;
+SYSCTL_PROC(_net_inet_ip, OID_AUTO, input_perf_bins,
+    CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &ip_input_measure_bins, 0,
+    sysctl_ip_input_measure_bins, "I",
+    "bins for chaining performance data histogram");
+
+static net_perf_t net_perf;
+SYSCTL_PROC(_net_inet_ip, OID_AUTO, input_perf_data,
+    CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
+    0, 0, sysctl_ip_input_getperf, "S,net_perf",
+    "IP input performance data (struct net_perf, net/net_perf.h)");
+#endif /* (DEBUG || DEVELOPMENT) */
 
 #if DIAGNOSTIC
 static int ipprintfs = 0;
@@ -257,36 +295,36 @@ static int ipprintfs = 0;
 
 struct protosw *ip_protox[IPPROTO_MAX];
 
-static lck_grp_attr_t  *in_ifaddr_rwlock_grp_attr;
-static lck_grp_t       *in_ifaddr_rwlock_grp;
-static lck_attr_t      *in_ifaddr_rwlock_attr;
+static lck_grp_attr_t   *in_ifaddr_rwlock_grp_attr;
+static lck_grp_t        *in_ifaddr_rwlock_grp;
+static lck_attr_t       *in_ifaddr_rwlock_attr;
 decl_lck_rw_data(, in_ifaddr_rwlock_data);
-lck_rw_t               *in_ifaddr_rwlock = &in_ifaddr_rwlock_data;
+lck_rw_t                *in_ifaddr_rwlock = &in_ifaddr_rwlock_data;
 
 /* Protected by in_ifaddr_rwlock */
-struct in_ifaddrhead in_ifaddrhead;            /* first inet address */
-struct in_ifaddrhashhead *in_ifaddrhashtbl;    /* inet addr hash table  */
+struct in_ifaddrhead in_ifaddrhead;             /* first inet address */
+struct in_ifaddrhashhead *in_ifaddrhashtbl;     /* inet addr hash table  */
 
-#define        INADDR_NHASH    61
-static u_int32_t inaddr_nhash;                 /* hash table size */
-static u_int32_t inaddr_hashp;                 /* next largest prime */
+#define INADDR_NHASH    61
+static u_int32_t inaddr_nhash;                  /* hash table size */
+static u_int32_t inaddr_hashp;                  /* next largest prime */
 
 static int ip_getstat SYSCTL_HANDLER_ARGS;
 struct ipstat ipstat;
 SYSCTL_PROC(_net_inet_ip, IPCTL_STATS, stats,
-       CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
-       0, 0, ip_getstat, "S,ipstat",
-       "IP statistics (struct ipstat, netinet/ip_var.h)");
+    CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
+    0, 0, ip_getstat, "S,ipstat",
+    "IP statistics (struct ipstat, netinet/ip_var.h)");
 
 #if IPCTL_DEFMTU
 SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW | CTLFLAG_LOCKED,
-       &ip_mtu, 0, "Default MTU");
+    &ip_mtu, 0, "Default MTU");
 #endif /* IPCTL_DEFMTU */
 
 #if IPSTEALTH
-static int     ipstealth = 0;
+static int      ipstealth = 0;
 SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_RW | CTLFLAG_LOCKED,
-       &ipstealth, 0, "");
+    &ipstealth, 0, "");
 #endif /* IPSTEALTH */
 
 /* Firewall hooks */
@@ -302,20 +340,20 @@ ip_dn_io_t *ip_dn_io_ptr;
 #endif /* DUMMYNET */
 
 SYSCTL_NODE(_net_inet_ip, OID_AUTO, linklocal,
-       CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local");
+    CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local");
 
 struct ip_linklocal_stat ip_linklocal_stat;
 SYSCTL_STRUCT(_net_inet_ip_linklocal, OID_AUTO, stat,
-       CTLFLAG_RD | CTLFLAG_LOCKED, &ip_linklocal_stat, ip_linklocal_stat,
-       "Number of link local packets with TTL less than 255");
+    CTLFLAG_RD | CTLFLAG_LOCKED, &ip_linklocal_stat, ip_linklocal_stat,
+    "Number of link local packets with TTL less than 255");
 
 SYSCTL_NODE(_net_inet_ip_linklocal, OID_AUTO, in,
-       CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local input");
+    CTLFLAG_RW | CTLFLAG_LOCKED, 0, "link local input");
 
 int ip_linklocal_in_allowbadttl = 1;
 SYSCTL_INT(_net_inet_ip_linklocal_in, OID_AUTO, allowbadttl,
-       CTLFLAG_RW | CTLFLAG_LOCKED, &ip_linklocal_in_allowbadttl, 0,
-       "Allow incoming link local packets with TTL less than 255");
+    CTLFLAG_RW | CTLFLAG_LOCKED, &ip_linklocal_in_allowbadttl, 0,
+    "Allow incoming link local packets with TTL less than 255");
 
 
 /*
@@ -325,12 +363,12 @@ SYSCTL_INT(_net_inet_ip_linklocal_in, OID_AUTO, allowbadttl,
  * maintenance when the remote end is on a network that is not known
  * to us.
  */
-static int     ip_nhops = 0;
-static struct ip_srcrt {
-       struct  in_addr dst;                    /* final destination */
-       char    nop;                            /* one NOP to align */
-       char    srcopt[IPOPT_OFFSET + 1];       /* OPTVAL, OLEN and OFFSET */
-       struct  in_addr route[MAX_IPOPTLEN / sizeof (struct in_addr)];
+static int      ip_nhops = 0;
+static  struct ip_srcrt {
+       struct  in_addr dst;                    /* final destination */
+       char    nop;                            /* one NOP to align */
+       char    srcopt[IPOPT_OFFSET + 1];       /* OPTVAL, OLEN and OFFSET */
+       struct  in_addr route[MAX_IPOPTLEN / sizeof(struct in_addr)];
 } ip_srcrt;
 
 static void in_ifaddrhashtbl_init(void);
@@ -353,7 +391,7 @@ static inline u_short ip_cksum(struct mbuf *, int);
 
 int ip_use_randomid = 1;
 SYSCTL_INT(_net_inet_ip, OID_AUTO, random_id, CTLFLAG_RW | CTLFLAG_LOCKED,
-       &ip_use_randomid, 0, "Randomize IP packets IDs");
+    &ip_use_randomid, 0, "Randomize IP packets IDs");
 
 /*
  * On platforms which require strict alignment (currently for anything but
@@ -363,27 +401,27 @@ SYSCTL_INT(_net_inet_ip, OID_AUTO, random_id, CTLFLAG_RW | CTLFLAG_LOCKED,
  * it's needed later on.
  */
 #if defined(__i386__) || defined(__x86_64__)
-#define        IP_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { } while (0)
+#define IP_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { } while (0)
 #else /* !__i386__ && !__x86_64__ */
-#define        IP_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do {                  \
-       if (!IP_HDR_ALIGNED_P(mtod(_m, caddr_t))) {                     \
-               struct mbuf *_n;                                        \
-               struct ifnet *__ifp = (_ifp);                           \
-               atomic_add_64(&(__ifp)->if_alignerrs, 1);               \
-               if (((_m)->m_flags & M_PKTHDR) &&                       \
-                   (_m)->m_pkthdr.pkt_hdr != NULL)                     \
-                       (_m)->m_pkthdr.pkt_hdr = NULL;                  \
-               _n = m_defrag_offset(_m, max_linkhdr, M_NOWAIT);        \
-               if (_n == NULL) {                                       \
-                       atomic_add_32(&ipstat.ips_toosmall, 1);         \
-                       m_freem(_m);                                    \
-                       (_m) = NULL;                                    \
-                       _action;                                        \
-               } else {                                                \
-                       VERIFY(_n != (_m));                             \
-                       (_m) = _n;                                      \
-               }                                                       \
-       }                                                               \
+#define IP_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do {                  \
+       if (!IP_HDR_ALIGNED_P(mtod(_m, caddr_t))) {                     \
+               struct mbuf *_n;                                        \
+               struct ifnet *__ifp = (_ifp);                           \
+               atomic_add_64(&(__ifp)->if_alignerrs, 1);               \
+               if (((_m)->m_flags & M_PKTHDR) &&                       \
+                   (_m)->m_pkthdr.pkt_hdr != NULL)                     \
+                       (_m)->m_pkthdr.pkt_hdr = NULL;                  \
+               _n = m_defrag_offset(_m, max_linkhdr, M_NOWAIT);        \
+               if (_n == NULL) {                                       \
+                       atomic_add_32(&ipstat.ips_toosmall, 1);         \
+                       m_freem(_m);                                    \
+                       (_m) = NULL;                                    \
+                       _action;                                        \
+               } else {                                                \
+                       VERIFY(_n != (_m));                             \
+                       (_m) = _n;                                      \
+               }                                                       \
+       }                                                               \
 } while (0)
 #endif /* !__i386__ && !__x86_64__ */
 
@@ -392,6 +430,26 @@ SYSCTL_INT(_net_inet_ip, OID_AUTO, random_id, CTLFLAG_RW | CTLFLAG_LOCKED,
  */
 static gre_input_func_t gre_input_func;
 
+static void
+ip_init_delayed(void)
+{
+       struct ifreq ifr;
+       int error;
+       struct sockaddr_in *sin;
+
+       bzero(&ifr, sizeof(ifr));
+       strlcpy(ifr.ifr_name, "lo0", sizeof(ifr.ifr_name));
+       sin = (struct sockaddr_in *)(void *)&ifr.ifr_addr;
+       sin->sin_len = sizeof(struct sockaddr_in);
+       sin->sin_family = AF_INET;
+       sin->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+       error = in_control(NULL, SIOCSIFADDR, (caddr_t)&ifr, lo_ifp, kernproc);
+       if (error) {
+               printf("%s: failed to initialise lo0's address, error=%d\n",
+                   __func__, error);
+       }
+}
+
 /*
  * IP initialization: fill in IP protocol switch table.
  * All protocols not implemented in kernel go to raw IP protocol handler.
@@ -405,24 +463,22 @@ ip_init(struct protosw *pp, struct domain *dp)
        int i;
 
        domain_proto_mtx_lock_assert_held();
-       VERIFY((pp->pr_flags & (PR_INITIALIZED|PR_ATTACHED)) == PR_ATTACHED);
+       VERIFY((pp->pr_flags & (PR_INITIALIZED | PR_ATTACHED)) == PR_ATTACHED);
 
        /* ipq_alloc() uses mbufs for IP fragment queue structures */
-       _CASSERT(sizeof (struct ipq) <= _MLEN);
+       _CASSERT(sizeof(struct ipq) <= _MLEN);
 
        /*
         * Some ioctls (e.g. SIOCAIFADDR) use ifaliasreq struct, which is
         * interchangeable with in_aliasreq; they must have the same size.
         */
-       _CASSERT(sizeof (struct ifaliasreq) == sizeof (struct in_aliasreq));
+       _CASSERT(sizeof(struct ifaliasreq) == sizeof(struct in_aliasreq));
 
-       if (ip_initialized)
+       if (ip_initialized) {
                return;
+       }
        ip_initialized = 1;
 
-       PE_parse_boot_argn("net.inet.ip.scopedroute",
-           &ip_doscopedroute, sizeof (ip_doscopedroute));
-
        in_ifaddr_init();
 
        in_ifaddr_rwlock_grp_attr = lck_grp_attr_alloc_init();
@@ -445,8 +501,9 @@ ip_init(struct protosw *pp, struct domain *dp)
        }
 
        /* Initialize the entire ip_protox[] array to IPPROTO_RAW. */
-       for (i = 0; i < IPPROTO_MAX; i++)
+       for (i = 0; i < IPPROTO_MAX; i++) {
                ip_protox[i] = pr;
+       }
        /*
         * Cycle through IP protocols and put them into the appropriate place
         * in ip_protox[], skipping protocols IPPROTO_{IP,RAW}.
@@ -456,8 +513,9 @@ ip_init(struct protosw *pp, struct domain *dp)
                VERIFY(pr->pr_domain == dp);
                if (pr->pr_protocol != 0 && pr->pr_protocol != IPPROTO_RAW) {
                        /* Be careful to only index valid IP protocols. */
-                       if (pr->pr_protocol < IPPROTO_MAX)
+                       if (pr->pr_protocol < IPPROTO_MAX) {
                                ip_protox[pr->pr_protocol] = pr;
+                       }
                }
        }
 
@@ -469,8 +527,9 @@ ip_init(struct protosw *pp, struct domain *dp)
 
        lck_mtx_lock(&ipqlock);
        /* Initialize IP reassembly queue. */
-       for (i = 0; i < IPREASS_NHASH; i++)
+       for (i = 0; i < IPREASS_NHASH; i++) {
                TAILQ_INIT(&ipq[i]);
+       }
 
        maxnipq = nmbclusters / 32;
        maxfragsperpacket = 128; /* enough for 64k in 512 byte fragments */
@@ -493,6 +552,7 @@ ip_init(struct protosw *pp, struct domain *dp)
 
 #endif
        arp_init();
+       net_init_add(ip_init_delayed);
 }
 
 /*
@@ -503,19 +563,22 @@ in_ifaddrhashtbl_init(void)
 {
        int i, k, p;
 
-       if (in_ifaddrhashtbl != NULL)
+       if (in_ifaddrhashtbl != NULL) {
                return;
+       }
 
        PE_parse_boot_argn("inaddr_nhash", &inaddr_nhash,
-           sizeof (inaddr_nhash));
-       if (inaddr_nhash == 0)
+           sizeof(inaddr_nhash));
+       if (inaddr_nhash == 0) {
                inaddr_nhash = INADDR_NHASH;
+       }
 
        MALLOC(in_ifaddrhashtbl, struct in_ifaddrhashhead *,
-           inaddr_nhash * sizeof (*in_ifaddrhashtbl),
+           inaddr_nhash * sizeof(*in_ifaddrhashtbl),
            M_IFADDR, M_WAITOK | M_ZERO);
-       if (in_ifaddrhashtbl == NULL)
+       if (in_ifaddrhashtbl == NULL) {
                panic("in_ifaddrhashtbl_init allocation failed");
+       }
 
        /*
         * Generate the next largest prime greater than inaddr_nhash.
@@ -524,11 +587,13 @@ in_ifaddrhashtbl_init(void)
        for (;;) {
                p = 1;
                for (i = 3; i * i <= k; i += 2) {
-                       if (k % i == 0)
+                       if (k % i == 0) {
                                p = 0;
+                       }
                }
-               if (p == 1)
+               if (p == 1) {
                        break;
+               }
                k += 2;
        }
        inaddr_hashp = k;
@@ -542,10 +607,11 @@ inaddr_hashval(u_int32_t key)
         * the hash size, as documented in "Introduction to Algorithms"
         * (Cormen, Leiserson, Rivest).
         */
-       if (inaddr_nhash > 1)
-               return ((key * inaddr_hashp) % inaddr_nhash);
-       else
-               return (0);
+       if (inaddr_nhash > 1) {
+               return (key * inaddr_hashp) % inaddr_nhash;
+       } else {
+               return 0;
+       }
 }
 
 void
@@ -560,82 +626,1247 @@ ip_proto_dispatch_in(struct mbuf *m, int hlen, u_int8_t proto,
 {
        struct ipfilter *filter;
        int seen = (inject_ipfref == NULL);
-       int     changed_header = 0;
+       int     changed_header = 0;
        struct ip *ip;
        void (*pr_input)(struct mbuf *, int len);
 
-       if (!TAILQ_EMPTY(&ipv4_filters)) {
-               ipf_ref();
-               TAILQ_FOREACH(filter, &ipv4_filters, ipf_link) {
-                       if (seen == 0) {
-                               if ((struct ipfilter *)inject_ipfref == filter)
-                                       seen = 1;
-                       } else if (filter->ipf_filter.ipf_input) {
-                               errno_t result;
+       if (!TAILQ_EMPTY(&ipv4_filters)) {
+               ipf_ref();
+               TAILQ_FOREACH(filter, &ipv4_filters, ipf_link) {
+                       if (seen == 0) {
+                               if ((struct ipfilter *)inject_ipfref == filter) {
+                                       seen = 1;
+                               }
+                       } else if (filter->ipf_filter.ipf_input) {
+                               errno_t result;
+
+                               if (changed_header == 0) {
+                                       /*
+                                        * Perform IP header alignment fixup,
+                                        * if needed, before passing packet
+                                        * into filter(s).
+                                        */
+                                       IP_HDR_ALIGNMENT_FIXUP(m,
+                                           m->m_pkthdr.rcvif, ipf_unref());
+
+                                       /* ipf_unref() already called */
+                                       if (m == NULL) {
+                                               return;
+                                       }
+
+                                       changed_header = 1;
+                                       ip = mtod(m, struct ip *);
+                                       ip->ip_len = htons(ip->ip_len + hlen);
+                                       ip->ip_off = htons(ip->ip_off);
+                                       ip->ip_sum = 0;
+                                       ip->ip_sum = ip_cksum_hdr_in(m, hlen);
+                               }
+                               result = filter->ipf_filter.ipf_input(
+                                       filter->ipf_filter.cookie, (mbuf_t *)&m,
+                                       hlen, proto);
+                               if (result == EJUSTRETURN) {
+                                       ipf_unref();
+                                       return;
+                               }
+                               if (result != 0) {
+                                       ipf_unref();
+                                       m_freem(m);
+                                       return;
+                               }
+                       }
+               }
+               ipf_unref();
+       }
+
+       /* Perform IP header alignment fixup (post-filters), if needed */
+       IP_HDR_ALIGNMENT_FIXUP(m, m->m_pkthdr.rcvif, return );
+
+       /*
+        * If there isn't a specific lock for the protocol
+        * we're about to call, use the generic lock for AF_INET.
+        * otherwise let the protocol deal with its own locking
+        */
+       ip = mtod(m, struct ip *);
+
+       if (changed_header) {
+               ip->ip_len = ntohs(ip->ip_len) - hlen;
+               ip->ip_off = ntohs(ip->ip_off);
+       }
+
+       if ((pr_input = ip_protox[ip->ip_p]->pr_input) == NULL) {
+               m_freem(m);
+       } else if (!(ip_protox[ip->ip_p]->pr_flags & PR_PROTOLOCK)) {
+               lck_mtx_lock(inet_domain_mutex);
+               pr_input(m, hlen);
+               lck_mtx_unlock(inet_domain_mutex);
+       } else {
+               pr_input(m, hlen);
+       }
+}
+
+struct pktchain_elm {
+       struct mbuf     *pkte_head;
+       struct mbuf     *pkte_tail;
+       struct in_addr  pkte_saddr;
+       struct in_addr  pkte_daddr;
+       uint16_t        pkte_npkts;
+       uint16_t        pkte_proto;
+       uint32_t        pkte_nbytes;
+};
+
+typedef struct pktchain_elm pktchain_elm_t;
+
+/* Store upto PKTTBL_SZ unique flows on the stack */
+#define PKTTBL_SZ       7
+
+static struct mbuf *
+ip_chain_insert(struct mbuf *packet, pktchain_elm_t *tbl)
+{
+       struct ip*      ip;
+       int             pkttbl_idx = 0;
+
+       ip = mtod(packet, struct ip*);
+
+       /* reusing the hash function from inaddr_hashval */
+       pkttbl_idx = inaddr_hashval(ntohs(ip->ip_src.s_addr)) % PKTTBL_SZ;
+       if (tbl[pkttbl_idx].pkte_head == NULL) {
+               tbl[pkttbl_idx].pkte_head = packet;
+               tbl[pkttbl_idx].pkte_saddr.s_addr = ip->ip_src.s_addr;
+               tbl[pkttbl_idx].pkte_daddr.s_addr = ip->ip_dst.s_addr;
+               tbl[pkttbl_idx].pkte_proto = ip->ip_p;
+       } else {
+               if ((ip->ip_dst.s_addr == tbl[pkttbl_idx].pkte_daddr.s_addr) &&
+                   (ip->ip_src.s_addr == tbl[pkttbl_idx].pkte_saddr.s_addr) &&
+                   (ip->ip_p == tbl[pkttbl_idx].pkte_proto)) {
+               } else {
+                       return packet;
+               }
+       }
+       if (tbl[pkttbl_idx].pkte_tail != NULL) {
+               mbuf_setnextpkt(tbl[pkttbl_idx].pkte_tail, packet);
+       }
+
+       tbl[pkttbl_idx].pkte_tail = packet;
+       tbl[pkttbl_idx].pkte_npkts += 1;
+       tbl[pkttbl_idx].pkte_nbytes += packet->m_pkthdr.len;
+       return NULL;
+}
+
+/* args is a dummy variable here for backward compatibility */
+static void
+ip_input_second_pass_loop_tbl(pktchain_elm_t *tbl, struct ip_fw_in_args *args)
+{
+       int i = 0;
+
+       for (i = 0; i < PKTTBL_SZ; i++) {
+               if (tbl[i].pkte_head != NULL) {
+                       struct mbuf *m = tbl[i].pkte_head;
+                       ip_input_second_pass(m, m->m_pkthdr.rcvif, 0,
+                           tbl[i].pkte_npkts, tbl[i].pkte_nbytes, args, 0);
+
+                       if (tbl[i].pkte_npkts > 2) {
+                               ipstat.ips_rxc_chainsz_gt2++;
+                       }
+                       if (tbl[i].pkte_npkts > 4) {
+                               ipstat.ips_rxc_chainsz_gt4++;
+                       }
+#if (DEBUG || DEVELOPMENT)
+                       if (ip_input_measure) {
+                               net_perf_histogram(&net_perf, tbl[i].pkte_npkts);
+                       }
+#endif /* (DEBUG || DEVELOPMENT) */
+                       tbl[i].pkte_head = tbl[i].pkte_tail = NULL;
+                       tbl[i].pkte_npkts = 0;
+                       tbl[i].pkte_nbytes = 0;
+                       /* no need to initialize address and protocol in tbl */
+               }
+       }
+}
+
+static void
+ip_input_cpout_args(struct ip_fw_in_args *args, struct ip_fw_args *args1,
+    boolean_t *done_init)
+{
+       if (*done_init == FALSE) {
+               bzero(args1, sizeof(struct ip_fw_args));
+               *done_init = TRUE;
+       }
+       args1->fwa_next_hop = args->fwai_next_hop;
+       args1->fwa_ipfw_rule = args->fwai_ipfw_rule;
+       args1->fwa_pf_rule = args->fwai_pf_rule;
+       args1->fwa_divert_rule = args->fwai_divert_rule;
+}
+
+static void
+ip_input_cpin_args(struct ip_fw_args *args1, struct ip_fw_in_args *args)
+{
+       args->fwai_next_hop = args1->fwa_next_hop;
+       args->fwai_ipfw_rule = args1->fwa_ipfw_rule;
+       args->fwai_pf_rule = args1->fwa_pf_rule;
+       args->fwai_divert_rule = args1->fwa_divert_rule;
+}
+
+typedef enum {
+       IPINPUT_DOCHAIN = 0,
+       IPINPUT_DONTCHAIN,
+       IPINPUT_FREED,
+       IPINPUT_DONE
+} ipinput_chain_ret_t;
+
+static void
+ip_input_update_nstat(struct ifnet *ifp, struct in_addr src_ip,
+    u_int32_t packets, u_int32_t bytes)
+{
+       if (nstat_collect) {
+               struct rtentry *rt = ifnet_cached_rtlookup_inet(ifp,
+                   src_ip);
+               if (rt != NULL) {
+                       nstat_route_rx(rt, packets, bytes, 0);
+                       rtfree(rt);
+               }
+       }
+}
+
+static void
+ip_input_dispatch_chain(struct mbuf *m)
+{
+       struct mbuf *tmp_mbuf = m;
+       struct mbuf *nxt_mbuf = NULL;
+       struct ip *ip = NULL;
+       unsigned int hlen;
+
+       ip = mtod(tmp_mbuf, struct ip *);
+       hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+       while (tmp_mbuf) {
+               nxt_mbuf = mbuf_nextpkt(tmp_mbuf);
+               mbuf_setnextpkt(tmp_mbuf, NULL);
+
+               if ((sw_lro) && (ip->ip_p == IPPROTO_TCP)) {
+                       tmp_mbuf = tcp_lro(tmp_mbuf, hlen);
+               }
+               if (tmp_mbuf) {
+                       ip_proto_dispatch_in(tmp_mbuf, hlen, ip->ip_p, 0);
+               }
+               tmp_mbuf = nxt_mbuf;
+               if (tmp_mbuf) {
+                       ip = mtod(tmp_mbuf, struct ip *);
+                       /* first mbuf of chain already has adjusted ip_len */
+                       hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+                       ip->ip_len -= hlen;
+               }
+       }
+}
+
+static void
+ip_input_setdst_chain(struct mbuf *m, uint32_t ifindex, struct in_ifaddr *ia)
+{
+       struct mbuf *tmp_mbuf = m;
+
+       while (tmp_mbuf) {
+               ip_setdstifaddr_info(tmp_mbuf, ifindex, ia);
+               tmp_mbuf = mbuf_nextpkt(tmp_mbuf);
+       }
+}
+
+static void
+ip_input_adjust(struct mbuf *m, struct ip *ip, struct ifnet *inifp)
+{
+       boolean_t adjust = TRUE;
+
+       ASSERT(m_pktlen(m) > ip->ip_len);
+
+       /*
+        * Invalidate hardware checksum info if ip_adj_clear_hwcksum
+        * is set; useful to handle buggy drivers.  Note that this
+        * should not be enabled by default, as we may get here due
+        * to link-layer padding.
+        */
+       if (ip_adj_clear_hwcksum &&
+           (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
+           !(inifp->if_flags & IFF_LOOPBACK) &&
+           !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
+               m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
+               m->m_pkthdr.csum_data = 0;
+               ipstat.ips_adj_hwcsum_clr++;
+       }
+
+       /*
+        * If partial checksum information is available, subtract
+        * out the partial sum of postpended extraneous bytes, and
+        * update the checksum metadata accordingly.  By doing it
+        * here, the upper layer transport only needs to adjust any
+        * prepended extraneous bytes (else it will do both.)
+        */
+       if (ip_adj_partial_sum &&
+           (m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PARTIAL)) ==
+           (CSUM_DATA_VALID | CSUM_PARTIAL)) {
+               m->m_pkthdr.csum_rx_val = m_adj_sum16(m,
+                   m->m_pkthdr.csum_rx_start, m->m_pkthdr.csum_rx_start,
+                   (ip->ip_len - m->m_pkthdr.csum_rx_start),
+                   m->m_pkthdr.csum_rx_val);
+       } else if ((m->m_pkthdr.csum_flags &
+           (CSUM_DATA_VALID | CSUM_PARTIAL)) ==
+           (CSUM_DATA_VALID | CSUM_PARTIAL)) {
+               /*
+                * If packet has partial checksum info and we decided not
+                * to subtract the partial sum of postpended extraneous
+                * bytes here (not the default case), leave that work to
+                * be handled by the other layers.  For now, only TCP, UDP
+                * layers are capable of dealing with this.  For all other
+                * protocols (including fragments), trim and ditch the
+                * partial sum as those layers might not implement partial
+                * checksumming (or adjustment) at all.
+                */
+               if ((ip->ip_off & (IP_MF | IP_OFFMASK)) == 0 &&
+                   (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)) {
+                       adjust = FALSE;
+               } else {
+                       m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
+                       m->m_pkthdr.csum_data = 0;
+                       ipstat.ips_adj_hwcsum_clr++;
+               }
+       }
+
+       if (adjust) {
+               ipstat.ips_adj++;
+               if (m->m_len == m->m_pkthdr.len) {
+                       m->m_len = ip->ip_len;
+                       m->m_pkthdr.len = ip->ip_len;
+               } else {
+                       m_adj(m, ip->ip_len - m->m_pkthdr.len);
+               }
+       }
+}
+
+/*
+ * First pass does all essential packet validation and places on a per flow
+ * queue for doing operations that have same outcome for all packets of a flow.
+ * div_info is packet divert/tee info
+ */
+static ipinput_chain_ret_t
+ip_input_first_pass(struct mbuf *m, u_int32_t *div_info,
+    struct ip_fw_in_args *args, int *ours, struct mbuf **modm)
+{
+       struct ip       *ip;
+       struct ifnet    *inifp;
+       unsigned int    hlen;
+       int             retval = IPINPUT_DOCHAIN;
+       int             len = 0;
+       struct in_addr  src_ip;
+#if IPFIREWALL
+       int             i;
+#endif
+#if IPFIREWALL || DUMMYNET
+       struct m_tag            *copy;
+       struct m_tag            *p;
+       boolean_t               delete = FALSE;
+       struct ip_fw_args       args1;
+       boolean_t               init = FALSE;
+#endif
+       ipfilter_t inject_filter_ref = NULL;
+
+#if !IPFIREWALL
+#pragma unused (args)
+#endif
+
+#if !IPDIVERT
+#pragma unused (div_info)
+#pragma unused (ours)
+#endif
+
+#if !IPFIREWALL_FORWARD
+#pragma unused (ours)
+#endif
+
+       /* Check if the mbuf is still valid after interface filter processing */
+       MBUF_INPUT_CHECK(m, m->m_pkthdr.rcvif);
+       inifp = mbuf_pkthdr_rcvif(m);
+       VERIFY(inifp != NULL);
+
+       /* Perform IP header alignment fixup, if needed */
+       IP_HDR_ALIGNMENT_FIXUP(m, inifp, goto bad);
+
+       m->m_pkthdr.pkt_flags &= ~PKTF_FORWARDED;
+
+#if IPFIREWALL || DUMMYNET
+
+       /*
+        * Don't bother searching for tag(s) if there's none.
+        */
+       if (SLIST_EMPTY(&m->m_pkthdr.tags)) {
+               goto ipfw_tags_done;
+       }
+
+       /* Grab info from mtags prepended to the chain */
+       p = m_tag_first(m);
+       while (p) {
+               if (p->m_tag_id == KERNEL_MODULE_TAG_ID) {
+#if DUMMYNET
+                       if (p->m_tag_type == KERNEL_TAG_TYPE_DUMMYNET) {
+                               struct dn_pkt_tag *dn_tag;
+
+                               dn_tag = (struct dn_pkt_tag *)(p + 1);
+                               args->fwai_ipfw_rule = dn_tag->dn_ipfw_rule;
+                               args->fwai_pf_rule = dn_tag->dn_pf_rule;
+                               delete = TRUE;
+                       }
+#endif
+
+#if IPDIVERT
+                       if (p->m_tag_type == KERNEL_TAG_TYPE_DIVERT) {
+                               struct divert_tag *div_tag;
+
+                               div_tag = (struct divert_tag *)(p + 1);
+                               args->fwai_divert_rule = div_tag->cookie;
+                               delete = TRUE;
+                       }
+#endif
+
+                       if (p->m_tag_type == KERNEL_TAG_TYPE_IPFORWARD) {
+                               struct ip_fwd_tag *ipfwd_tag;
+
+                               ipfwd_tag = (struct ip_fwd_tag *)(p + 1);
+                               args->fwai_next_hop = ipfwd_tag->next_hop;
+                               delete = TRUE;
+                       }
+
+                       if (delete) {
+                               copy = p;
+                               p = m_tag_next(m, p);
+                               m_tag_delete(m, copy);
+                       } else {
+                               p = m_tag_next(m, p);
+                       }
+               } else {
+                       p = m_tag_next(m, p);
+               }
+       }
+
+#if DIAGNOSTIC
+       if (m == NULL || !(m->m_flags & M_PKTHDR)) {
+               panic("ip_input no HDR");
+       }
+#endif
+
+#if DUMMYNET
+       if (args->fwai_ipfw_rule || args->fwai_pf_rule) {
+               /* dummynet already filtered us */
+               ip = mtod(m, struct ip *);
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+               inject_filter_ref = ipf_get_inject_filter(m);
+#if IPFIREWALL
+               if (args->fwai_ipfw_rule) {
+                       goto iphack;
+               }
+#endif /* IPFIREWALL */
+               if (args->fwai_pf_rule) {
+                       goto check_with_pf;
+               }
+       }
+#endif /* DUMMYNET */
+ipfw_tags_done:
+#endif /* IPFIREWALL || DUMMYNET */
+
+       /*
+        * No need to process packet twice if we've already seen it.
+        */
+       if (!SLIST_EMPTY(&m->m_pkthdr.tags)) {
+               inject_filter_ref = ipf_get_inject_filter(m);
+       }
+       if (inject_filter_ref != NULL) {
+               ip = mtod(m, struct ip *);
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+
+               DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
+                   struct ip *, ip, struct ifnet *, inifp,
+                   struct ip *, ip, struct ip6_hdr *, NULL);
+
+               ip->ip_len = ntohs(ip->ip_len) - hlen;
+               ip->ip_off = ntohs(ip->ip_off);
+               ip_proto_dispatch_in(m, hlen, ip->ip_p, inject_filter_ref);
+               return IPINPUT_DONE;
+       }
+
+       if (m->m_pkthdr.len < sizeof(struct ip)) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               OSAddAtomic(1, &ipstat.ips_tooshort);
+               m_freem(m);
+               return IPINPUT_FREED;
+       }
+
+       if (m->m_len < sizeof(struct ip) &&
+           (m = m_pullup(m, sizeof(struct ip))) == NULL) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               OSAddAtomic(1, &ipstat.ips_toosmall);
+               return IPINPUT_FREED;
+       }
+
+       ip = mtod(m, struct ip *);
+       *modm = m;
+
+       KERNEL_DEBUG(DBG_LAYER_BEG, ip->ip_dst.s_addr, ip->ip_src.s_addr,
+           ip->ip_p, ip->ip_off, ip->ip_len);
+
+       if (IP_VHL_V(ip->ip_vhl) != IPVERSION) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               OSAddAtomic(1, &ipstat.ips_badvers);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               m_freem(m);
+               return IPINPUT_FREED;
+       }
+
+       hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+       if (hlen < sizeof(struct ip)) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               OSAddAtomic(1, &ipstat.ips_badhlen);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               m_freem(m);
+               return IPINPUT_FREED;
+       }
+
+       if (hlen > m->m_len) {
+               if ((m = m_pullup(m, hlen)) == NULL) {
+                       OSAddAtomic(1, &ipstat.ips_total);
+                       OSAddAtomic(1, &ipstat.ips_badhlen);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       return IPINPUT_FREED;
+               }
+               ip = mtod(m, struct ip *);
+               *modm = m;
+       }
+
+       /* 127/8 must not appear on wire - RFC1122 */
+       if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
+           (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
+               /*
+                * Allow for the following exceptions:
+                *
+                *   1. If the packet was sent to loopback (i.e. rcvif
+                *      would have been set earlier at output time.)
+                *
+                *   2. If the packet was sent out on loopback from a local
+                *      source address which belongs to a non-loopback
+                *      interface (i.e. rcvif may not necessarily be a
+                *      loopback interface, hence the test for PKTF_LOOP.)
+                *      Unlike IPv6, there is no interface scope ID, and
+                *      therefore we don't care so much about PKTF_IFINFO.
+                */
+               if (!(inifp->if_flags & IFF_LOOPBACK) &&
+                   !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
+                       OSAddAtomic(1, &ipstat.ips_total);
+                       OSAddAtomic(1, &ipstat.ips_badaddr);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       m_freem(m);
+                       return IPINPUT_FREED;
+               }
+       }
+
+       /* IPv4 Link-Local Addresses as defined in RFC3927 */
+       if ((IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) ||
+           IN_LINKLOCAL(ntohl(ip->ip_src.s_addr)))) {
+               ip_linklocal_stat.iplls_in_total++;
+               if (ip->ip_ttl != MAXTTL) {
+                       OSAddAtomic(1, &ip_linklocal_stat.iplls_in_badttl);
+                       /* Silently drop link local traffic with bad TTL */
+                       if (!ip_linklocal_in_allowbadttl) {
+                               OSAddAtomic(1, &ipstat.ips_total);
+                               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                               m_freem(m);
+                               return IPINPUT_FREED;
+                       }
+               }
+       }
+
+       if (ip_cksum(m, hlen)) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               m_freem(m);
+               return IPINPUT_FREED;
+       }
+
+       DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
+           struct ip *, ip, struct ifnet *, inifp,
+           struct ip *, ip, struct ip6_hdr *, NULL);
+
+       /*
+        * Convert fields to host representation.
+        */
+#if BYTE_ORDER != BIG_ENDIAN
+       NTOHS(ip->ip_len);
+#endif
+
+       if (ip->ip_len < hlen) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               OSAddAtomic(1, &ipstat.ips_badlen);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               m_freem(m);
+               return IPINPUT_FREED;
+       }
+
+#if BYTE_ORDER != BIG_ENDIAN
+       NTOHS(ip->ip_off);
+#endif
+
+       /*
+        * Check that the amount of data in the buffers
+        * is as at least much as the IP header would have us expect.
+        * Trim mbufs if longer than we expect.
+        * Drop packet if shorter than we expect.
+        */
+       if (m->m_pkthdr.len < ip->ip_len) {
+               OSAddAtomic(1, &ipstat.ips_total);
+               OSAddAtomic(1, &ipstat.ips_tooshort);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               m_freem(m);
+               return IPINPUT_FREED;
+       }
+
+       if (m->m_pkthdr.len > ip->ip_len) {
+               ip_input_adjust(m, ip, inifp);
+       }
+
+       /* for consistency */
+       m->m_pkthdr.pkt_proto = ip->ip_p;
+
+       /* for netstat route statistics */
+       src_ip = ip->ip_src;
+       len = m->m_pkthdr.len;
+
+#if DUMMYNET
+check_with_pf:
+#endif
+#if PF
+       /* Invoke inbound packet filter */
+       if (PF_IS_ENABLED) {
+               int error;
+               ip_input_cpout_args(args, &args1, &init);
+               ip = mtod(m, struct ip *);
+               src_ip = ip->ip_src;
+
+#if DUMMYNET
+               error = pf_af_hook(inifp, NULL, &m, AF_INET, TRUE, &args1);
+#else
+               error = pf_af_hook(inifp, NULL, &m, AF_INET, TRUE, NULL);
+#endif /* DUMMYNET */
+               if (error != 0 || m == NULL) {
+                       if (m != NULL) {
+                               panic("%s: unexpected packet %p\n",
+                                   __func__, m);
+                               /* NOTREACHED */
+                       }
+                       /* Already freed by callee */
+                       ip_input_update_nstat(inifp, src_ip, 1, len);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       OSAddAtomic(1, &ipstat.ips_total);
+                       return IPINPUT_FREED;
+               }
+               ip = mtod(m, struct ip *);
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+               *modm = m;
+               ip_input_cpin_args(&args1, args);
+       }
+#endif /* PF */
+
+#if IPSEC
+       if (ipsec_bypass == 0 && ipsec_gethist(m, NULL)) {
+               retval = IPINPUT_DONTCHAIN; /* XXX scope for chaining here? */
+               goto pass;
+       }
+#endif
+
+#if IPFIREWALL
+#if DUMMYNET
+iphack:
+#endif /* DUMMYNET */
+       /*
+        * Check if we want to allow this packet to be processed.
+        * Consider it to be bad if not.
+        */
+       if (fw_enable && IPFW_LOADED) {
+#if IPFIREWALL_FORWARD
+               /*
+                * If we've been forwarded from the output side, then
+                * skip the firewall a second time
+                */
+               if (args->fwai_next_hop) {
+                       *ours = 1;
+                       return IPINPUT_DONTCHAIN;
+               }
+#endif  /* IPFIREWALL_FORWARD */
+               ip_input_cpout_args(args, &args1, &init);
+               args1.fwa_m = m;
+
+               i = ip_fw_chk_ptr(&args1);
+               m = args1.fwa_m;
+
+               if ((i & IP_FW_PORT_DENY_FLAG) || m == NULL) { /* drop */
+                       if (m) {
+                               m_freem(m);
+                       }
+                       ip_input_update_nstat(inifp, src_ip, 1, len);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       OSAddAtomic(1, &ipstat.ips_total);
+                       return IPINPUT_FREED;
+               }
+               ip = mtod(m, struct ip *); /* just in case m changed */
+               *modm = m;
+               ip_input_cpin_args(&args1, args);
+
+               if (i == 0 && args->fwai_next_hop == NULL) { /* common case */
+                       goto pass;
+               }
+#if DUMMYNET
+               if (DUMMYNET_LOADED && (i & IP_FW_PORT_DYNT_FLAG) != 0) {
+                       /* Send packet to the appropriate pipe */
+                       ip_dn_io_ptr(m, i & 0xffff, DN_TO_IP_IN, &args1,
+                           DN_CLIENT_IPFW);
+                       ip_input_update_nstat(inifp, src_ip, 1, len);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       OSAddAtomic(1, &ipstat.ips_total);
+                       return IPINPUT_FREED;
+               }
+#endif /* DUMMYNET */
+#if IPDIVERT
+               if (i != 0 && (i & IP_FW_PORT_DYNT_FLAG) == 0) {
+                       /* Divert or tee packet */
+                       *div_info = i;
+                       *ours = 1;
+                       return IPINPUT_DONTCHAIN;
+               }
+#endif
+#if IPFIREWALL_FORWARD
+               if (i == 0 && args->fwai_next_hop != NULL) {
+                       retval = IPINPUT_DONTCHAIN;
+                       goto pass;
+               }
+#endif
+               /*
+                * if we get here, the packet must be dropped
+                */
+               ip_input_update_nstat(inifp, src_ip, 1, len);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               m_freem(m);
+               OSAddAtomic(1, &ipstat.ips_total);
+               return IPINPUT_FREED;
+       }
+#endif /* IPFIREWALL */
+#if IPSEC | IPFIREWALL
+pass:
+#endif
+       /*
+        * Process options and, if not destined for us,
+        * ship it on.  ip_dooptions returns 1 when an
+        * error was detected (causing an icmp message
+        * to be sent and the original packet to be freed).
+        */
+       ip_nhops = 0;           /* for source routed packets */
+#if IPFIREWALL
+       if (hlen > sizeof(struct ip) &&
+           ip_dooptions(m, 0, args->fwai_next_hop)) {
+#else /* !IPFIREWALL */
+       if (hlen > sizeof(struct ip) && ip_dooptions(m, 0, NULL)) {
+#endif /* !IPFIREWALL */
+               ip_input_update_nstat(inifp, src_ip, 1, len);
+               KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+               OSAddAtomic(1, &ipstat.ips_total);
+               return IPINPUT_FREED;
+       }
+
+       /*
+        * Don't chain fragmented packets as the process of determining
+        * if it is our fragment or someone else's plus the complexity of
+        * divert and fw args makes it harder to do chaining.
+        */
+       if (ip->ip_off & ~(IP_DF | IP_RF)) {
+               return IPINPUT_DONTCHAIN;
+       }
+
+       /* Allow DHCP/BootP responses through */
+       if ((inifp->if_eflags & IFEF_AUTOCONFIGURING) &&
+           hlen == sizeof(struct ip) && ip->ip_p == IPPROTO_UDP) {
+               struct udpiphdr *ui;
+
+               if (m->m_len < sizeof(struct udpiphdr) &&
+                   (m = m_pullup(m, sizeof(struct udpiphdr))) == NULL) {
+                       OSAddAtomic(1, &udpstat.udps_hdrops);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       OSAddAtomic(1, &ipstat.ips_total);
+                       return IPINPUT_FREED;
+               }
+               *modm = m;
+               ui = mtod(m, struct udpiphdr *);
+               if (ntohs(ui->ui_dport) == IPPORT_BOOTPC) {
+                       ip_setdstifaddr_info(m, inifp->if_index, NULL);
+                       return IPINPUT_DONTCHAIN;
+               }
+       }
+
+       /* Avoid chaining raw sockets as ipsec checks occur later for them */
+       if (ip_protox[ip->ip_p]->pr_flags & PR_LASTHDR) {
+               return IPINPUT_DONTCHAIN;
+       }
+
+       return retval;
+#if !defined(__i386__) && !defined(__x86_64__)
+bad:
+       m_freem(m);
+       return IPINPUT_FREED;
+#endif
+}
+
+static void
+ip_input_second_pass(struct mbuf *m, struct ifnet *inifp, u_int32_t div_info,
+    int npkts_in_chain, int bytes_in_chain, struct ip_fw_in_args *args, int ours)
+{
+       unsigned int            checkif;
+       struct mbuf             *tmp_mbuf = NULL;
+       struct in_ifaddr        *ia = NULL;
+       struct in_addr          pkt_dst;
+       unsigned int            hlen;
+
+#if !IPFIREWALL
+#pragma unused (args)
+#endif
+
+#if !IPDIVERT
+#pragma unused (div_info)
+#endif
+
+       struct ip *ip = mtod(m, struct ip *);
+       hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+
+       OSAddAtomic(npkts_in_chain, &ipstat.ips_total);
+
+       /*
+        * Naively assume we can attribute inbound data to the route we would
+        * use to send to this destination. Asymmetric routing breaks this
+        * assumption, but it still allows us to account for traffic from
+        * a remote node in the routing table.
+        * this has a very significant performance impact so we bypass
+        * if nstat_collect is disabled. We may also bypass if the
+        * protocol is tcp in the future because tcp will have a route that
+        * we can use to attribute the data to. That does mean we would not
+        * account for forwarded tcp traffic.
+        */
+       ip_input_update_nstat(inifp, ip->ip_src, npkts_in_chain,
+           bytes_in_chain);
+
+       if (ours) {
+               goto ours;
+       }
+
+       /*
+        * Check our list of addresses, to see if the packet is for us.
+        * If we don't have any addresses, assume any unicast packet
+        * we receive might be for us (and let the upper layers deal
+        * with it).
+        */
+       tmp_mbuf = m;
+       if (TAILQ_EMPTY(&in_ifaddrhead)) {
+               while (tmp_mbuf) {
+                       if (!(tmp_mbuf->m_flags & (M_MCAST | M_BCAST))) {
+                               ip_setdstifaddr_info(tmp_mbuf, inifp->if_index,
+                                   NULL);
+                       }
+                       tmp_mbuf = mbuf_nextpkt(tmp_mbuf);
+               }
+               goto ours;
+       }
+       /*
+        * Cache the destination address of the packet; this may be
+        * changed by use of 'ipfw fwd'.
+        */
+#if IPFIREWALL
+       pkt_dst = args->fwai_next_hop == NULL ?
+           ip->ip_dst : args->fwai_next_hop->sin_addr;
+#else /* !IPFIREWALL */
+       pkt_dst = ip->ip_dst;
+#endif /* !IPFIREWALL */
+
+       /*
+        * Enable a consistency check between the destination address
+        * and the arrival interface for a unicast packet (the RFC 1122
+        * strong ES model) if IP forwarding is disabled and the packet
+        * is not locally generated and the packet is not subject to
+        * 'ipfw fwd'.
+        *
+        * XXX - Checking also should be disabled if the destination
+        * address is ipnat'ed to a different interface.
+        *
+        * XXX - Checking is incompatible with IP aliases added
+        * to the loopback interface instead of the interface where
+        * the packets are received.
+        */
+       checkif = ip_checkinterface && (ipforwarding == 0) &&
+           !(inifp->if_flags & IFF_LOOPBACK) &&
+           !(m->m_pkthdr.pkt_flags & PKTF_LOOP)
+#if IPFIREWALL
+           && (args->fwai_next_hop == NULL);
+#else /* !IPFIREWALL */
+       ;
+#endif /* !IPFIREWALL */
+
+       /*
+        * Check for exact addresses in the hash bucket.
+        */
+       lck_rw_lock_shared(in_ifaddr_rwlock);
+       TAILQ_FOREACH(ia, INADDR_HASH(pkt_dst.s_addr), ia_hash) {
+               /*
+                * If the address matches, verify that the packet
+                * arrived via the correct interface if checking is
+                * enabled.
+                */
+               if (IA_SIN(ia)->sin_addr.s_addr == pkt_dst.s_addr &&
+                   (!checkif || ia->ia_ifp == inifp)) {
+                       ip_input_setdst_chain(m, 0, ia);
+                       lck_rw_done(in_ifaddr_rwlock);
+                       goto ours;
+               }
+       }
+       lck_rw_done(in_ifaddr_rwlock);
+
+       /*
+        * Check for broadcast addresses.
+        *
+        * Only accept broadcast packets that arrive via the matching
+        * interface.  Reception of forwarded directed broadcasts would be
+        * handled via ip_forward() and ether_frameout() with the loopback
+        * into the stack for SIMPLEX interfaces handled by ether_frameout().
+        */
+       if (inifp->if_flags & IFF_BROADCAST) {
+               struct ifaddr *ifa;
+
+               ifnet_lock_shared(inifp);
+               TAILQ_FOREACH(ifa, &inifp->if_addrhead, ifa_link) {
+                       if (ifa->ifa_addr->sa_family != AF_INET) {
+                               continue;
+                       }
+                       ia = ifatoia(ifa);
+                       if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
+                           pkt_dst.s_addr || ia->ia_netbroadcast.s_addr ==
+                           pkt_dst.s_addr) {
+                               ip_input_setdst_chain(m, 0, ia);
+                               ifnet_lock_done(inifp);
+                               goto ours;
+                       }
+               }
+               ifnet_lock_done(inifp);
+       }
+
+       if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
+               struct in_multi *inm;
+               /*
+                * See if we belong to the destination multicast group on the
+                * arrival interface.
+                */
+               in_multihead_lock_shared();
+               IN_LOOKUP_MULTI(&ip->ip_dst, inifp, inm);
+               in_multihead_lock_done();
+               if (inm == NULL) {
+                       OSAddAtomic(npkts_in_chain, &ipstat.ips_notmember);
+                       m_freem_list(m);
+                       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+                       return;
+               }
+               ip_input_setdst_chain(m, inifp->if_index, NULL);
+               INM_REMREF(inm);
+               goto ours;
+       }
+
+       if (ip->ip_dst.s_addr == (u_int32_t)INADDR_BROADCAST ||
+           ip->ip_dst.s_addr == INADDR_ANY) {
+               ip_input_setdst_chain(m, inifp->if_index, NULL);
+               goto ours;
+       }
+
+       if (ip->ip_p == IPPROTO_UDP) {
+               struct udpiphdr *ui;
+               ui = mtod(m, struct udpiphdr *);
+               if (ntohs(ui->ui_dport) == IPPORT_BOOTPC) {
+                       goto ours;
+               }
+       }
+
+       tmp_mbuf = m;
+       struct mbuf *nxt_mbuf = NULL;
+       while (tmp_mbuf) {
+               nxt_mbuf = mbuf_nextpkt(tmp_mbuf);
+               /*
+                * Not for us; forward if possible and desirable.
+                */
+               mbuf_setnextpkt(tmp_mbuf, NULL);
+               if (ipforwarding == 0) {
+                       OSAddAtomic(1, &ipstat.ips_cantforward);
+                       m_freem(tmp_mbuf);
+               } else {
+#if IPFIREWALL
+                       ip_forward(tmp_mbuf, 0, args->fwai_next_hop);
+#else
+                       ip_forward(tmp_mbuf, 0, NULL);
+#endif
+               }
+               tmp_mbuf = nxt_mbuf;
+       }
+       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+       return;
+ours:
+       /*
+        * If offset or IP_MF are set, must reassemble.
+        */
+       if (ip->ip_off & ~(IP_DF | IP_RF)) {
+               VERIFY(npkts_in_chain == 1);
+               /*
+                * ip_reass() will return a different mbuf, and update
+                * the divert info in div_info and args->fwai_divert_rule.
+                */
+#if IPDIVERT
+               m = ip_reass(m, (u_int16_t *)&div_info, &args->fwai_divert_rule);
+#else
+               m = ip_reass(m);
+#endif
+               if (m == NULL) {
+                       return;
+               }
+               ip = mtod(m, struct ip *);
+               /* Get the header length of the reassembled packet */
+               hlen = IP_VHL_HL(ip->ip_vhl) << 2;
+#if IPDIVERT
+               /* Restore original checksum before diverting packet */
+               if (div_info != 0) {
+                       VERIFY(npkts_in_chain == 1);
+#if BYTE_ORDER != BIG_ENDIAN
+                       HTONS(ip->ip_len);
+                       HTONS(ip->ip_off);
+#endif
+                       ip->ip_sum = 0;
+                       ip->ip_sum = ip_cksum_hdr_in(m, hlen);
+#if BYTE_ORDER != BIG_ENDIAN
+                       NTOHS(ip->ip_off);
+                       NTOHS(ip->ip_len);
+#endif
+               }
+#endif
+       }
+
+       /*
+        * Further protocols expect the packet length to be w/o the
+        * IP header.
+        */
+       ip->ip_len -= hlen;
+
+#if IPDIVERT
+       /*
+        * Divert or tee packet to the divert protocol if required.
+        *
+        * If div_info is zero then cookie should be too, so we shouldn't
+        * need to clear them here.  Assume divert_packet() does so also.
+        */
+       if (div_info != 0) {
+               struct mbuf *clone = NULL;
+               VERIFY(npkts_in_chain == 1);
+
+               /* Clone packet if we're doing a 'tee' */
+               if (div_info & IP_FW_PORT_TEE_FLAG) {
+                       clone = m_dup(m, M_DONTWAIT);
+               }
+
+               /* Restore packet header fields to original values */
+               ip->ip_len += hlen;
+
+#if BYTE_ORDER != BIG_ENDIAN
+               HTONS(ip->ip_len);
+               HTONS(ip->ip_off);
+#endif
+               /* Deliver packet to divert input routine */
+               OSAddAtomic(1, &ipstat.ips_delivered);
+               divert_packet(m, 1, div_info & 0xffff, args->fwai_divert_rule);
+
+               /* If 'tee', continue with original packet */
+               if (clone == NULL) {
+                       return;
+               }
+               m = clone;
+               ip = mtod(m, struct ip *);
+       }
+#endif
+
+#if IPSEC
+       /*
+        * enforce IPsec policy checking if we are seeing last header.
+        * note that we do not visit this with protocols with pcb layer
+        * code - like udp/tcp/raw ip.
+        */
+       if (ipsec_bypass == 0 && (ip_protox[ip->ip_p]->pr_flags & PR_LASTHDR)) {
+               VERIFY(npkts_in_chain == 1);
+               if (ipsec4_in_reject(m, NULL)) {
+                       IPSEC_STAT_INCREMENT(ipsecstat.in_polvio);
+                       goto bad;
+               }
+       }
+#endif /* IPSEC */
+
+       /*
+        * Switch out to protocol's input routine.
+        */
+       OSAddAtomic(npkts_in_chain, &ipstat.ips_delivered);
+
+#if IPFIREWALL
+       if (args->fwai_next_hop && ip->ip_p == IPPROTO_TCP) {
+               /* TCP needs IPFORWARD info if available */
+               struct m_tag *fwd_tag;
+               struct ip_fwd_tag *ipfwd_tag;
+
+               VERIFY(npkts_in_chain == 1);
+               fwd_tag = m_tag_create(KERNEL_MODULE_TAG_ID,
+                   KERNEL_TAG_TYPE_IPFORWARD, sizeof(*ipfwd_tag),
+                   M_NOWAIT, m);
+               if (fwd_tag == NULL) {
+                       goto bad;
+               }
+
+               ipfwd_tag = (struct ip_fwd_tag *)(fwd_tag + 1);
+               ipfwd_tag->next_hop = args->fwai_next_hop;
+
+               m_tag_prepend(m, fwd_tag);
+
+               KERNEL_DEBUG(DBG_LAYER_END, ip->ip_dst.s_addr,
+                   ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
+
+               /* TCP deals with its own locking */
+               ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
+       } else {
+               KERNEL_DEBUG(DBG_LAYER_END, ip->ip_dst.s_addr,
+                   ip->ip_src.s_addr, ip->ip_p, ip->ip_off, ip->ip_len);
 
-                               if (changed_header == 0) {
-                                       /*
-                                        * Perform IP header alignment fixup,
-                                        * if needed, before passing packet
-                                        * into filter(s).
-                                        */
-                                       IP_HDR_ALIGNMENT_FIXUP(m,
-                                           m->m_pkthdr.rcvif, ipf_unref());
+               ip_input_dispatch_chain(m);
+       }
+#else /* !IPFIREWALL */
+       ip_input_dispatch_chain(m);
 
-                                       /* ipf_unref() already called */
-                                       if (m == NULL)
-                                               return;
+#endif /* !IPFIREWALL */
+       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+       return;
+bad:
+       KERNEL_DEBUG(DBG_LAYER_END, 0, 0, 0, 0, 0);
+       m_freem(m);
+}
 
-                                       changed_header = 1;
-                                       ip = mtod(m, struct ip *);
-                                       ip->ip_len = htons(ip->ip_len + hlen);
-                                       ip->ip_off = htons(ip->ip_off);
-                                       ip->ip_sum = 0;
-                                       ip->ip_sum = ip_cksum_hdr_in(m, hlen);
-                               }
-                               result = filter->ipf_filter.ipf_input(
-                                   filter->ipf_filter.cookie, (mbuf_t *)&m,
-                                   hlen, proto);
-                               if (result == EJUSTRETURN) {
-                                       ipf_unref();
-                                       return;
-                               }
-                               if (result != 0) {
-                                       ipf_unref();
-                                       m_freem(m);
-                                       return;
+void
+ip_input_process_list(struct mbuf *packet_list)
+{
+       pktchain_elm_t  pktchain_tbl[PKTTBL_SZ];
+
+       struct mbuf     *packet = NULL;
+       struct mbuf     *modm = NULL; /* modified mbuf */
+       int             retval = 0;
+       u_int32_t       div_info = 0;
+       int             ours = 0;
+#if (DEBUG || DEVELOPMENT)
+       struct timeval start_tv;
+#endif /* (DEBUG || DEVELOPMENT) */
+       int     num_pkts = 0;
+       int chain = 0;
+       struct ip_fw_in_args       args;
+
+       if (ip_chaining == 0) {
+               struct mbuf *m = packet_list;
+#if (DEBUG || DEVELOPMENT)
+               if (ip_input_measure) {
+                       net_perf_start_time(&net_perf, &start_tv);
+               }
+#endif /* (DEBUG || DEVELOPMENT) */
+
+               while (m) {
+                       packet_list = mbuf_nextpkt(m);
+                       mbuf_setnextpkt(m, NULL);
+                       ip_input(m);
+                       m = packet_list;
+                       num_pkts++;
+               }
+#if (DEBUG || DEVELOPMENT)
+               if (ip_input_measure) {
+                       net_perf_measure_time(&net_perf, &start_tv, num_pkts);
+               }
+#endif /* (DEBUG || DEVELOPMENT) */
+               return;
+       }
+#if (DEBUG || DEVELOPMENT)
+       if (ip_input_measure) {
+               net_perf_start_time(&net_perf, &start_tv);
+       }
+#endif /* (DEBUG || DEVELOPMENT) */
+
+       bzero(&pktchain_tbl, sizeof(pktchain_tbl));
+restart_list_process:
+       chain = 0;
+       for (packet = packet_list; packet; packet = packet_list) {
+               packet_list = mbuf_nextpkt(packet);
+               mbuf_setnextpkt(packet, NULL);
+
+               num_pkts++;
+               modm = NULL;
+               div_info = 0;
+               bzero(&args, sizeof(args));
+
+               retval = ip_input_first_pass(packet, &div_info, &args,
+                   &ours, &modm);
+
+               if (retval == IPINPUT_DOCHAIN) {
+                       if (modm) {
+                               packet = modm;
+                       }
+                       packet = ip_chain_insert(packet, &pktchain_tbl[0]);
+                       if (packet == NULL) {
+                               ipstat.ips_rxc_chained++;
+                               chain++;
+                               if (chain > ip_chainsz) {
+                                       break;
                                }
+                       } else {
+                               ipstat.ips_rxc_collisions++;
+                               break;
+                       }
+               } else if (retval == IPINPUT_DONTCHAIN) {
+                       /* in order to preserve order, exit from chaining */
+                       if (modm) {
+                               packet = modm;
                        }
+                       ipstat.ips_rxc_notchain++;
+                       break;
+               } else {
+                       /* packet was freed or delivered, do nothing. */
                }
-               ipf_unref();
        }
 
-       /* Perform IP header alignment fixup (post-filters), if needed */
-       IP_HDR_ALIGNMENT_FIXUP(m, m->m_pkthdr.rcvif, return);
+       /* do second pass here for pktchain_tbl */
+       if (chain) {
+               ip_input_second_pass_loop_tbl(&pktchain_tbl[0], &args);
+       }
 
-       /*
-        * If there isn't a specific lock for the protocol
-        * we're about to call, use the generic lock for AF_INET.
-        * otherwise let the protocol deal with its own locking
-        */
-       ip = mtod(m, struct ip *);
+       if (packet) {
+               /*
+                * equivalent update in chaining case if performed in
+                * ip_input_second_pass_loop_tbl().
+                */
+#if (DEBUG || DEVELOPMENT)
+               if (ip_input_measure) {
+                       net_perf_histogram(&net_perf, 1);
+               }
+#endif /* (DEBUG || DEVELOPMENT) */
+               ip_input_second_pass(packet, packet->m_pkthdr.rcvif, div_info,
+                   1, packet->m_pkthdr.len, &args, ours);
+       }
 
-       if (changed_header) {
-               ip->ip_len = ntohs(ip->ip_len) - hlen;
-               ip->ip_off = ntohs(ip->ip_off);
+       if (packet_list) {
+               goto restart_list_process;
        }
 
-       if ((pr_input = ip_protox[ip->ip_p]->pr_input) == NULL) {
-               m_freem(m);
-       } else if (!(ip_protox[ip->ip_p]->pr_flags & PR_PROTOLOCK)) {
-               lck_mtx_lock(inet_domain_mutex);
-               pr_input(m, hlen);
-               lck_mtx_unlock(inet_domain_mutex);
-       } else {
-               pr_input(m, hlen);
+#if (DEBUG || DEVELOPMENT)
+       if (ip_input_measure) {
+               net_perf_measure_time(&net_perf, &start_tv, num_pkts);
        }
+#endif /* (DEBUG || DEVELOPMENT) */
 }
-
 /*
  * Ip input routine.  Checksum and byte swap header.  If fragmented
  * try to reassemble.  Process options.  Pass to next level.
@@ -650,11 +1881,11 @@ ip_input(struct mbuf *m)
        struct in_addr pkt_dst;
 #if IPFIREWALL
        int i;
-       u_int32_t div_info = 0;         /* packet divert/tee info */
+       u_int32_t div_info = 0;         /* packet divert/tee info */
 #endif
 #if IPFIREWALL || DUMMYNET
        struct ip_fw_args args;
-       struct m_tag    *tag;
+       struct m_tag    *tag;
 #endif
        ipfilter_t inject_filter_ref = NULL;
        struct ifnet *inifp;
@@ -664,19 +1895,22 @@ ip_input(struct mbuf *m)
        inifp = m->m_pkthdr.rcvif;
        VERIFY(inifp != NULL);
 
+       ipstat.ips_rxc_notlist++;
+
        /* Perform IP header alignment fixup, if needed */
        IP_HDR_ALIGNMENT_FIXUP(m, inifp, goto bad);
 
        m->m_pkthdr.pkt_flags &= ~PKTF_FORWARDED;
 
 #if IPFIREWALL || DUMMYNET
-       bzero(&args, sizeof (struct ip_fw_args));
+       bzero(&args, sizeof(struct ip_fw_args));
 
        /*
         * Don't bother searching for tag(s) if there's none.
         */
-       if (SLIST_EMPTY(&m->m_pkthdr.tags))
+       if (SLIST_EMPTY(&m->m_pkthdr.tags)) {
                goto ipfw_tags_done;
+       }
 
        /* Grab info from mtags prepended to the chain */
 #if DUMMYNET
@@ -684,7 +1918,7 @@ ip_input(struct mbuf *m)
            KERNEL_TAG_TYPE_DUMMYNET, NULL)) != NULL) {
                struct dn_pkt_tag *dn_tag;
 
-               dn_tag = (struct dn_pkt_tag *)(tag+1);
+               dn_tag = (struct dn_pkt_tag *)(tag + 1);
                args.fwa_ipfw_rule = dn_tag->dn_ipfw_rule;
                args.fwa_pf_rule = dn_tag->dn_pf_rule;
 
@@ -697,7 +1931,7 @@ ip_input(struct mbuf *m)
            KERNEL_TAG_TYPE_DIVERT, NULL)) != NULL) {
                struct divert_tag *div_tag;
 
-               div_tag = (struct divert_tag *)(tag+1);
+               div_tag = (struct divert_tag *)(tag + 1);
                args.fwa_divert_rule = div_tag->cookie;
 
                m_tag_delete(m, tag);
@@ -708,15 +1942,16 @@ ip_input(struct mbuf *m)
            KERNEL_TAG_TYPE_IPFORWARD, NULL)) != NULL) {
                struct ip_fwd_tag *ipfwd_tag;
 
-               ipfwd_tag = (struct ip_fwd_tag *)(tag+1);
+               ipfwd_tag = (struct ip_fwd_tag *)(tag + 1);
                args.fwa_next_hop = ipfwd_tag->next_hop;
 
                m_tag_delete(m, tag);
        }
 
-#if    DIAGNOSTIC
-       if (m == NULL || !(m->m_flags & M_PKTHDR))
+#if     DIAGNOSTIC
+       if (m == NULL || !(m->m_flags & M_PKTHDR)) {
                panic("ip_input no HDR");
+       }
 #endif
 
 #if DUMMYNET
@@ -726,11 +1961,13 @@ ip_input(struct mbuf *m)
                hlen = IP_VHL_HL(ip->ip_vhl) << 2;
                inject_filter_ref = ipf_get_inject_filter(m);
 #if IPFIREWALL
-               if (args.fwa_ipfw_rule)
+               if (args.fwa_ipfw_rule) {
                        goto iphack;
+               }
 #endif /* IPFIREWALL */
-               if (args.fwa_pf_rule)
+               if (args.fwa_pf_rule) {
                        goto check_with_pf;
+               }
        }
 #endif /* DUMMYNET */
 ipfw_tags_done:
@@ -739,8 +1976,9 @@ ipfw_tags_done:
        /*
         * No need to process packet twice if we've already seen it.
         */
-       if (!SLIST_EMPTY(&m->m_pkthdr.tags))
+       if (!SLIST_EMPTY(&m->m_pkthdr.tags)) {
                inject_filter_ref = ipf_get_inject_filter(m);
+       }
        if (inject_filter_ref != NULL) {
                ip = mtod(m, struct ip *);
                hlen = IP_VHL_HL(ip->ip_vhl) << 2;
@@ -756,11 +1994,12 @@ ipfw_tags_done:
        }
 
        OSAddAtomic(1, &ipstat.ips_total);
-       if (m->m_pkthdr.len < sizeof (struct ip))
+       if (m->m_pkthdr.len < sizeof(struct ip)) {
                goto tooshort;
+       }
 
-       if (m->m_len < sizeof (struct ip) &&
-           (m = m_pullup(m, sizeof (struct ip))) == NULL) {
+       if (m->m_len < sizeof(struct ip) &&
+           (m = m_pullup(m, sizeof(struct ip))) == NULL) {
                OSAddAtomic(1, &ipstat.ips_toosmall);
                return;
        }
@@ -775,7 +2014,7 @@ ipfw_tags_done:
        }
 
        hlen = IP_VHL_HL(ip->ip_vhl) << 2;
-       if (hlen < sizeof (struct ip)) {        /* minimum header length */
+       if (hlen < sizeof(struct ip)) {         /* minimum header length */
                OSAddAtomic(1, &ipstat.ips_badhlen);
                goto bad;
        }
@@ -817,8 +2056,9 @@ ipfw_tags_done:
                if (ip->ip_ttl != MAXTTL) {
                        OSAddAtomic(1, &ip_linklocal_stat.iplls_in_badttl);
                        /* Silently drop link local traffic with bad TTL */
-                       if (!ip_linklocal_in_allowbadttl)
+                       if (!ip_linklocal_in_allowbadttl) {
                                goto bad;
+                       }
                }
        }
 
@@ -833,7 +2073,7 @@ ipfw_tags_done:
 
        /*
         * Naively assume we can attribute inbound data to the route we would
-        * use to send to this destination. Asymetric routing breaks this
+        * use to send to this destination. Asymmetric routing breaks this
         * assumption, but it still allows us to account for traffic from
         * a remote node in the routing table.
         * this has a very significant performance impact so we bypass
@@ -878,27 +2118,7 @@ tooshort:
                goto bad;
        }
        if (m->m_pkthdr.len > ip->ip_len) {
-               /*
-                * Invalidate hardware checksum info if ip_adj_clear_hwcksum
-                * is set; useful to handle buggy drivers.  Note that this
-                * should not be enabled by default, as we may get here due
-                * to link-layer padding.
-                */
-               if (ip_adj_clear_hwcksum &&
-                   (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
-                   !(inifp->if_flags & IFF_LOOPBACK) &&
-                   !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
-                       m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
-                       m->m_pkthdr.csum_data = 0;
-                       ipstat.ips_adj_hwcsum_clr++;
-               }
-
-               ipstat.ips_adj++;
-               if (m->m_len == m->m_pkthdr.len) {
-                       m->m_len = ip->ip_len;
-                       m->m_pkthdr.len = ip->ip_len;
-               } else
-                       m_adj(m, ip->ip_len - m->m_pkthdr.len);
+               ip_input_adjust(m, ip, inifp);
        }
 
        /* for consistency */
@@ -931,8 +2151,9 @@ check_with_pf:
 #endif /* PF */
 
 #if IPSEC
-       if (ipsec_bypass == 0 && ipsec_gethist(m, NULL))
+       if (ipsec_bypass == 0 && ipsec_gethist(m, NULL)) {
                goto pass;
+       }
 #endif
 
 #if IPFIREWALL
@@ -949,9 +2170,10 @@ iphack:
                 * If we've been forwarded from the output side, then
                 * skip the firewall a second time
                 */
-               if (args.fwa_next_hop)
+               if (args.fwa_next_hop) {
                        goto ours;
-#endif /* IPFIREWALL_FORWARD */
+               }
+#endif  /* IPFIREWALL_FORWARD */
 
                args.fwa_m = m;
 
@@ -959,8 +2181,9 @@ iphack:
                m = args.fwa_m;
 
                if ((i & IP_FW_PORT_DENY_FLAG) || m == NULL) { /* drop */
-                       if (m)
+                       if (m) {
                                m_freem(m);
+                       }
                        return;
                }
                ip = mtod(m, struct ip *); /* just in case m changed */
@@ -971,7 +2194,7 @@ iphack:
 #if DUMMYNET
                if (DUMMYNET_LOADED && (i & IP_FW_PORT_DYNT_FLAG) != 0) {
                        /* Send packet to the appropriate pipe */
-                       ip_dn_io_ptr(m, i&0xffff, DN_TO_IP_IN, &args,
+                       ip_dn_io_ptr(m, i & 0xffff, DN_TO_IP_IN, &args,
                            DN_CLIENT_IPFW);
                        return;
                }
@@ -1004,12 +2227,12 @@ pass:
         * error was detected (causing an icmp message
         * to be sent and the original packet to be freed).
         */
-       ip_nhops = 0;           /* for source routed packets */
+       ip_nhops = 0;           /* for source routed packets */
 #if IPFIREWALL
-       if (hlen > sizeof (struct ip) &&
+       if (hlen > sizeof(struct ip) &&
            ip_dooptions(m, 0, args.fwa_next_hop)) {
 #else /* !IPFIREWALL */
-       if (hlen > sizeof (struct ip) && ip_dooptions(m, 0, NULL)) {
+       if (hlen > sizeof(struct ip) && ip_dooptions(m, 0, NULL)) {
 #endif /* !IPFIREWALL */
                return;
        }
@@ -1020,7 +2243,7 @@ pass:
         * we receive might be for us (and let the upper layers deal
         * with it).
         */
-       if (TAILQ_EMPTY(&in_ifaddrhead) && !(m->m_flags & (M_MCAST|M_BCAST))) {
+       if (TAILQ_EMPTY(&in_ifaddrhead) && !(m->m_flags & (M_MCAST | M_BCAST))) {
                ip_setdstifaddr_info(m, inifp->if_index, NULL);
                goto ours;
        }
@@ -1056,7 +2279,7 @@ pass:
 #if IPFIREWALL
            && (args.fwa_next_hop == NULL);
 #else /* !IPFIREWALL */
-               ;
+       ;
 #endif /* !IPFIREWALL */
 
        /*
@@ -1132,11 +2355,11 @@ pass:
 
        /* Allow DHCP/BootP responses through */
        if ((inifp->if_eflags & IFEF_AUTOCONFIGURING) &&
-           hlen == sizeof (struct ip) && ip->ip_p == IPPROTO_UDP) {
+           hlen == sizeof(struct ip) && ip->ip_p == IPPROTO_UDP) {
                struct udpiphdr *ui;
 
-               if (m->m_len < sizeof (struct udpiphdr) &&
-                   (m = m_pullup(m, sizeof (struct udpiphdr))) == NULL) {
+               if (m->m_len < sizeof(struct udpiphdr) &&
+                   (m = m_pullup(m, sizeof(struct udpiphdr))) == NULL) {
                        OSAddAtomic(1, &udpstat.udps_hdrops);
                        return;
                }
@@ -1177,8 +2400,9 @@ ours:
 #else
                m = ip_reass(m);
 #endif
-               if (m == NULL)
+               if (m == NULL) {
                        return;
+               }
                ip = mtod(m, struct ip *);
                /* Get the header length of the reassembled packet */
                hlen = IP_VHL_HL(ip->ip_vhl) << 2;
@@ -1216,8 +2440,9 @@ ours:
                struct mbuf *clone = NULL;
 
                /* Clone packet if we're doing a 'tee' */
-               if (div_info & IP_FW_PORT_TEE_FLAG)
+               if (div_info & IP_FW_PORT_TEE_FLAG) {
                        clone = m_dup(m, M_DONTWAIT);
+               }
 
                /* Restore packet header fields to original values */
                ip->ip_len += hlen;
@@ -1265,12 +2490,13 @@ ours:
                struct ip_fwd_tag *ipfwd_tag;
 
                fwd_tag = m_tag_create(KERNEL_MODULE_TAG_ID,
-                   KERNEL_TAG_TYPE_IPFORWARD, sizeof (*ipfwd_tag),
+                   KERNEL_TAG_TYPE_IPFORWARD, sizeof(*ipfwd_tag),
                    M_NOWAIT, m);
-               if (fwd_tag == NULL)
+               if (fwd_tag == NULL) {
                        goto bad;
+               }
 
-               ipfwd_tag = (struct ip_fwd_tag *)(fwd_tag+1);
+               ipfwd_tag = (struct ip_fwd_tag *)(fwd_tag + 1);
                ipfwd_tag->next_hop = args.fwa_next_hop;
 
                m_tag_prepend(m, fwd_tag);
@@ -1286,8 +2512,9 @@ ours:
 
                if ((sw_lro) && (ip->ip_p == IPPROTO_TCP)) {
                        m = tcp_lro(m, hlen);
-                       if (m == NULL)
+                       if (m == NULL) {
                                return;
+                       }
                }
 
                ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
@@ -1295,8 +2522,9 @@ ours:
 #else /* !IPFIREWALL */
        if ((sw_lro) && (ip->ip_p == IPPROTO_TCP)) {
                m = tcp_lro(m, hlen);
-               if (m == NULL)
+               if (m == NULL) {
                        return;
+               }
        }
        ip_proto_dispatch_in(m, hlen, ip->ip_p, 0);
 #endif /* !IPFIREWALL */
@@ -1310,24 +2538,27 @@ bad:
 static void
 ipq_updateparams(void)
 {
-       lck_mtx_assert(&ipqlock, LCK_MTX_ASSERT_OWNED);
+       LCK_MTX_ASSERT(&ipqlock, LCK_MTX_ASSERT_OWNED);
        /*
         * -1 for unlimited allocation.
         */
-       if (maxnipq < 0)
+       if (maxnipq < 0) {
                ipq_limit = 0;
+       }
        /*
         * Positive number for specific bound.
         */
-       if (maxnipq > 0)
+       if (maxnipq > 0) {
                ipq_limit = maxnipq;
+       }
        /*
         * Zero specifies no further fragment queue allocation -- set the
         * bound very low, but rely on implementation elsewhere to actually
         * prevent allocation and reclaim current queues.
         */
-       if (maxnipq == 0)
+       if (maxnipq == 0) {
                ipq_limit = 1;
+       }
        /*
         * Arm the purge timer if not already and if there's work to do
         */
@@ -1343,8 +2574,9 @@ sysctl_maxnipq SYSCTL_HANDLER_ARGS
        lck_mtx_lock(&ipqlock);
        i = maxnipq;
        error = sysctl_handle_int(oidp, &i, 0, req);
-       if (error || req->newptr == USER_ADDR_NULL)
+       if (error || req->newptr == USER_ADDR_NULL) {
                goto done;
+       }
        /* impose bounds */
        if (i < -1 || i > (nmbclusters / 4)) {
                error = EINVAL;
@@ -1354,7 +2586,7 @@ sysctl_maxnipq SYSCTL_HANDLER_ARGS
        ipq_updateparams();
 done:
        lck_mtx_unlock(&ipqlock);
-       return (error);
+       return error;
 }
 
 static int
@@ -1366,13 +2598,14 @@ sysctl_maxfragsperpacket SYSCTL_HANDLER_ARGS
        lck_mtx_lock(&ipqlock);
        i = maxfragsperpacket;
        error = sysctl_handle_int(oidp, &i, 0, req);
-       if (error || req->newptr == USER_ADDR_NULL)
+       if (error || req->newptr == USER_ADDR_NULL) {
                goto done;
+       }
        maxfragsperpacket = i;
-       ipq_updateparams();     /* see if we need to arm timer */
+       ipq_updateparams();     /* see if we need to arm timer */
 done:
        lck_mtx_unlock(&ipqlock);
-       return (error);
+       return error;
 }
 
 /*
@@ -1383,7 +2616,7 @@ done:
  * When IPDIVERT enabled, keep additional state with each packet that
  * tells us if we need to divert or tee the packet we're building.
  *
- * The IP header is *NOT* adjusted out of iplen.
+ * The IP header is *NOT* adjusted out of iplen (but in host byte order).
  */
 static struct mbuf *
 #if IPDIVERT
@@ -1408,7 +2641,7 @@ ip_reass(struct mbuf *m)
        uint16_t hash;
        struct fq_head dfq;
 
-       MBUFQ_INIT(&dfq);       /* for deferred frees */
+       MBUFQ_INIT(&dfq);       /* for deferred frees */
 
        /* If maxnipq or maxfragsperpacket is 0, never accept fragments. */
        if (maxnipq == 0 || maxfragsperpacket == 0) {
@@ -1417,10 +2650,10 @@ ip_reass(struct mbuf *m)
                m_freem(m);
                if (nipq > 0) {
                        lck_mtx_lock(&ipqlock);
-                       frag_sched_timeout();   /* purge stale fragments */
+                       frag_sched_timeout();   /* purge stale fragments */
                        lck_mtx_unlock(&ipqlock);
                }
-               return (NULL);
+               return NULL;
        }
 
        ip = mtod(m, struct ip *);
@@ -1442,8 +2675,9 @@ ip_reass(struct mbuf *m)
 #if CONFIG_MACF_NET
                    mac_ipq_label_compare(m, fp) &&
 #endif
-                   ip->ip_p == fp->ipq_p)
+                   ip->ip_p == fp->ipq_p) {
                        goto found;
+               }
        }
 
        fp = NULL;
@@ -1481,35 +2715,52 @@ found:
         *
         * Perform 1's complement adjustment of octets that got included/
         * excluded in the hardware-calculated checksum value.  Ignore cases
-        * where the value includes or excludes the IP header span, as the
-        * sum for those octets would already be 0xffff and thus no-op.
+        * where the value includes the entire IPv4 header span, as the sum
+        * for those octets would already be 0 by the time we get here; IP
+        * has already performed its header checksum validation.  Also take
+        * care of any trailing bytes and subtract out their partial sum.
         */
-       if (ip->ip_p == IPPROTO_UDP && hlen == sizeof (struct ip) &&
+       if (ip->ip_p == IPPROTO_UDP && hlen == sizeof(struct ip) &&
            (m->m_pkthdr.csum_flags &
            (CSUM_DATA_VALID | CSUM_PARTIAL | CSUM_PSEUDO_HDR)) ==
            (CSUM_DATA_VALID | CSUM_PARTIAL)) {
-               uint32_t start;
+               uint32_t start = m->m_pkthdr.csum_rx_start;
+               int32_t trailer = (m_pktlen(m) - ip->ip_len);
+               uint32_t swbytes = (uint32_t)trailer;
 
-               start = m->m_pkthdr.csum_rx_start;
                csum = m->m_pkthdr.csum_rx_val;
 
-               if (start != 0 && start != hlen) {
+               ASSERT(trailer >= 0);
+               if ((start != 0 && start != hlen) || trailer != 0) {
 #if BYTE_ORDER != BIG_ENDIAN
                        if (start < hlen) {
                                HTONS(ip->ip_len);
                                HTONS(ip->ip_off);
                        }
-#endif
+#endif /* BYTE_ORDER != BIG_ENDIAN */
                        /* callee folds in sum */
-                       csum = m_adj_sum16(m, start, hlen, csum);
+                       csum = m_adj_sum16(m, start, hlen,
+                           (ip->ip_len - hlen), csum);
+                       if (hlen > start) {
+                               swbytes += (hlen - start);
+                       } else {
+                               swbytes += (start - hlen);
+                       }
 #if BYTE_ORDER != BIG_ENDIAN
                        if (start < hlen) {
                                NTOHS(ip->ip_off);
                                NTOHS(ip->ip_len);
                        }
-#endif
+#endif /* BYTE_ORDER != BIG_ENDIAN */
                }
                csum_flags = m->m_pkthdr.csum_flags;
+
+               if (swbytes != 0) {
+                       udp_in_cksum_stats(swbytes);
+               }
+               if (trailer != 0) {
+                       m_adj(m, -trailer);
+               }
        } else {
                csum = 0;
                csum_flags = 0;
@@ -1564,8 +2815,9 @@ found:
         */
        if (fp == NULL) {
                fp = ipq_alloc(M_DONTWAIT);
-               if (fp == NULL)
+               if (fp == NULL) {
                        goto dropfrag;
+               }
 #if CONFIG_MACF_NET
                if (mac_ipq_label_init(fp, M_NOWAIT) != 0) {
                        ipq_free(fp);
@@ -1608,7 +2860,7 @@ found:
                *divinfo = 0;
                *divcookie = 0;
 #endif /* IPDIVERT */
-               m = NULL;       /* nothing to return */
+               m = NULL;       /* nothing to return */
                goto done;
        } else {
                fp->ipq_nfrags++;
@@ -1617,7 +2869,7 @@ found:
 #endif
        }
 
-#define        GETIP(m)        ((struct ip *)((m)->m_pkthdr.pkt_hdr))
+#define GETIP(m)        ((struct ip *)((m)->m_pkthdr.pkt_hdr))
 
        /*
         * Handle ECN by comparing this segment with the first one;
@@ -1627,20 +2879,25 @@ found:
        ecn = ip->ip_tos & IPTOS_ECN_MASK;
        ecn0 = GETIP(fp->ipq_frags)->ip_tos & IPTOS_ECN_MASK;
        if (ecn == IPTOS_ECN_CE) {
-               if (ecn0 == IPTOS_ECN_NOTECT)
+               if (ecn0 == IPTOS_ECN_NOTECT) {
                        goto dropfrag;
-               if (ecn0 != IPTOS_ECN_CE)
+               }
+               if (ecn0 != IPTOS_ECN_CE) {
                        GETIP(fp->ipq_frags)->ip_tos |= IPTOS_ECN_CE;
+               }
        }
-       if (ecn == IPTOS_ECN_NOTECT && ecn0 != IPTOS_ECN_NOTECT)
+       if (ecn == IPTOS_ECN_NOTECT && ecn0 != IPTOS_ECN_NOTECT) {
                goto dropfrag;
+       }
 
        /*
         * Find a segment which begins after this one does.
         */
-       for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt)
-               if (GETIP(q)->ip_off > ip->ip_off)
+       for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) {
+               if (GETIP(q)->ip_off > ip->ip_off) {
                        break;
+               }
+       }
 
        /*
         * If there is a preceding segment, it may provide some of
@@ -1654,8 +2911,9 @@ found:
        if (p) {
                i = GETIP(p)->ip_off + GETIP(p)->ip_len - ip->ip_off;
                if (i > 0) {
-                       if (i >= ip->ip_len)
+                       if (i >= ip->ip_len) {
                                goto dropfrag;
+                       }
                        m_adj(m, i);
                        fp->ipq_csum_flags = 0;
                        ip->ip_off += i;
@@ -1695,10 +2953,11 @@ found:
         * as that of the existing ones, accumulate checksum.  Otherwise,
         * invalidate checksum offload info for the entire datagram.
         */
-       if (csum_flags != 0 && csum_flags == fp->ipq_csum_flags)
+       if (csum_flags != 0 && csum_flags == fp->ipq_csum_flags) {
                fp->ipq_csum += csum;
-       else if (fp->ipq_csum_flags != 0)
+       } else if (fp->ipq_csum_flags != 0) {
                fp->ipq_csum_flags = 0;
+       }
 
 #if IPDIVERT
        /*
@@ -1734,7 +2993,7 @@ found:
                                ipstat.ips_fragdropped += fp->ipq_nfrags;
                                frag_freef(head, fp);
                        }
-                       m = NULL;       /* nothing to return */
+                       m = NULL;       /* nothing to return */
                        goto done;
                }
                next += GETIP(q)->ip_len;
@@ -1745,7 +3004,7 @@ found:
                        ipstat.ips_fragdropped += fp->ipq_nfrags;
                        frag_freef(head, fp);
                }
-               m = NULL;               /* nothing to return */
+               m = NULL;               /* nothing to return */
                goto done;
        }
 
@@ -1758,7 +3017,7 @@ found:
                ipstat.ips_toolong++;
                ipstat.ips_fragdropped += fp->ipq_nfrags;
                frag_freef(head, fp);
-               m = NULL;               /* nothing to return */
+               m = NULL;               /* nothing to return */
                goto done;
        }
 
@@ -1788,7 +3047,7 @@ found:
                ADDCARRY(csum);
 
                m->m_pkthdr.csum_rx_val = csum;
-               m->m_pkthdr.csum_rx_start = sizeof (struct ip);
+               m->m_pkthdr.csum_rx_start = sizeof(struct ip);
                m->m_pkthdr.csum_flags = fp->ipq_csum_flags;
        } else if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) ||
            (m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
@@ -1825,25 +3084,27 @@ found:
        ip->ip_src = fp->ipq_src;
        ip->ip_dst = fp->ipq_dst;
 
-       fp->ipq_frags = NULL;   /* return to caller as 'm' */
+       fp->ipq_frags = NULL;   /* return to caller as 'm' */
        frag_freef(head, fp);
        fp = NULL;
 
        m->m_len += (IP_VHL_HL(ip->ip_vhl) << 2);
        m->m_data -= (IP_VHL_HL(ip->ip_vhl) << 2);
        /* some debugging cruft by sklower, below, will go away soon */
-       if (m->m_flags & M_PKTHDR)      /* XXX this should be done elsewhere */
+       if (m->m_flags & M_PKTHDR) {    /* XXX this should be done elsewhere */
                m_fixhdr(m);
+       }
        ipstat.ips_reassembled++;
 
        /* arm the purge timer if not already and if there's work to do */
        frag_sched_timeout();
        lck_mtx_unlock(&ipqlock);
        /* perform deferred free (if needed) now that lock is dropped */
-       if (!MBUFQ_EMPTY(&dfq))
+       if (!MBUFQ_EMPTY(&dfq)) {
                MBUFQ_DRAIN(&dfq);
+       }
        VERIFY(MBUFQ_EMPTY(&dfq));
-       return (m);
+       return m;
 
 done:
        VERIFY(m == NULL);
@@ -1851,10 +3112,11 @@ done:
        frag_sched_timeout();
        lck_mtx_unlock(&ipqlock);
        /* perform deferred free (if needed) */
-       if (!MBUFQ_EMPTY(&dfq))
+       if (!MBUFQ_EMPTY(&dfq)) {
                MBUFQ_DRAIN(&dfq);
+       }
        VERIFY(MBUFQ_EMPTY(&dfq));
-       return (NULL);
+       return NULL;
 
 dropfrag:
 #if IPDIVERT
@@ -1862,17 +3124,19 @@ dropfrag:
        *divcookie = 0;
 #endif /* IPDIVERT */
        ipstat.ips_fragdropped++;
-       if (fp != NULL)
+       if (fp != NULL) {
                fp->ipq_nfrags--;
+       }
        /* arm the purge timer if not already and if there's work to do */
        frag_sched_timeout();
        lck_mtx_unlock(&ipqlock);
        m_freem(m);
        /* perform deferred free (if needed) */
-       if (!MBUFQ_EMPTY(&dfq))
+       if (!MBUFQ_EMPTY(&dfq)) {
                MBUFQ_DRAIN(&dfq);
+       }
        VERIFY(MBUFQ_EMPTY(&dfq));
-       return (NULL);
+       return NULL;
 #undef GETIP
 }
 
@@ -1883,7 +3147,7 @@ dropfrag:
 static void
 frag_freef(struct ipqhead *fhp, struct ipq *fp)
 {
-       lck_mtx_assert(&ipqlock, LCK_MTX_ASSERT_OWNED);
+       LCK_MTX_ASSERT(&ipqlock, LCK_MTX_ASSERT_OWNED);
 
        fp->ipq_nfrags = 0;
        if (fp->ipq_frags != NULL) {
@@ -1914,7 +3178,7 @@ frag_timeout(void *arg)
 
        lck_mtx_lock(&ipqlock);
        for (i = 0; i < IPREASS_NHASH; i++) {
-               for (fp = TAILQ_FIRST(&ipq[i]); fp; ) {
+               for (fp = TAILQ_FIRST(&ipq[i]); fp;) {
                        struct ipq *fpp;
 
                        fpp = fp;
@@ -1949,7 +3213,7 @@ frag_timeout(void *arg)
 static void
 frag_sched_timeout(void)
 {
-       lck_mtx_assert(&ipqlock, LCK_MTX_ASSERT_OWNED);
+       LCK_MTX_ASSERT(&ipqlock, LCK_MTX_ASSERT_OWNED);
 
        if (!frag_timeout_run && nipq > 0) {
                frag_timeout_run = 1;
@@ -1987,18 +3251,19 @@ ipq_alloc(int how)
         * from nipq since the latter represents the elements already
         * in the reassembly queues.
         */
-       if (ipq_limit > 0 && ipq_count > ipq_limit)
-               return (NULL);
+       if (ipq_limit > 0 && ipq_count > ipq_limit) {
+               return NULL;
+       }
 
        t = m_get(how, MT_FTABLE);
        if (t != NULL) {
                atomic_add_32(&ipq_count, 1);
                fp = mtod(t, struct ipq *);
-               bzero(fp, sizeof (*fp));
+               bzero(fp, sizeof(*fp));
        } else {
                fp = NULL;
        }
-       return (fp);
+       return fp;
 }
 
 static void
@@ -2014,9 +3279,9 @@ ipq_free(struct ipq *fp)
 void
 ip_drain(void)
 {
-       frag_drain();           /* fragments */
-       in_rtqdrain();          /* protocol cloned routes */
-       in_arpdrain(NULL);      /* cloned routes: ARP */
+       frag_drain();           /* fragments */
+       in_rtqdrain();          /* protocol cloned routes */
+       in_arpdrain(NULL);      /* cloned routes: ARP */
 }
 
 /*
@@ -2041,36 +3306,37 @@ ip_dooptions(struct mbuf *m, int pass, struct sockaddr_in *next_hop)
        struct in_ifaddr *ia;
        int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0;
        struct in_addr *sin, dst;
-       n_time ntime;
+       u_int32_t ntime;
        struct sockaddr_in ipaddr = {
-           sizeof (ipaddr), AF_INET, 0, { 0 }, { 0, } };
+               sizeof(ipaddr), AF_INET, 0, { 0 }, { 0, }
+       };
 
        /* Expect 32-bit aligned data pointer on strict-align platforms */
        MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
 
        dst = ip->ip_dst;
        cp = (u_char *)(ip + 1);
-       cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
+       cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
        for (; cnt > 0; cnt -= optlen, cp += optlen) {
                opt = cp[IPOPT_OPTVAL];
-               if (opt == IPOPT_EOL)
+               if (opt == IPOPT_EOL) {
                        break;
-               if (opt == IPOPT_NOP)
+               }
+               if (opt == IPOPT_NOP) {
                        optlen = 1;
-               else {
-                       if (cnt < IPOPT_OLEN + sizeof (*cp)) {
+               else {
+                       if (cnt < IPOPT_OLEN + sizeof(*cp)) {
                                code = &cp[IPOPT_OLEN] - (u_char *)ip;
                                goto bad;
                        }
                        optlen = cp[IPOPT_OLEN];
-                       if (optlen < IPOPT_OLEN + sizeof (*cp) ||
+                       if (optlen < IPOPT_OLEN + sizeof(*cp) ||
                            optlen > cnt) {
                                code = &cp[IPOPT_OLEN] - (u_char *)ip;
                                goto bad;
                        }
                }
                switch (opt) {
-
                default:
                        break;
 
@@ -2085,7 +3351,7 @@ ip_dooptions(struct mbuf *m, int pass, struct sockaddr_in *next_hop)
                 */
                case IPOPT_LSRR:
                case IPOPT_SSRR:
-                       if (optlen < IPOPT_OFFSET + sizeof (*cp)) {
+                       if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
                                code = &cp[IPOPT_OLEN] - (u_char *)ip;
                                goto bad;
                        }
@@ -2101,8 +3367,9 @@ ip_dooptions(struct mbuf *m, int pass, struct sockaddr_in *next_hop)
                                        code = ICMP_UNREACH_SRCFAIL;
                                        goto bad;
                                }
-                               if (!ip_dosourceroute)
+                               if (!ip_dosourceroute) {
                                        goto nosourcerouting;
+                               }
                                /*
                                 * Loose routing, and not at next destination
                                 * yet; nothing to do except forward.
@@ -2112,13 +3379,14 @@ ip_dooptions(struct mbuf *m, int pass, struct sockaddr_in *next_hop)
                                IFA_REMREF(&ia->ia_ifa);
                                ia = NULL;
                        }
-                       off--;                  /* 0 origin */
-                       if (off > optlen - (int)sizeof (struct in_addr)) {
+                       off--;                  /* 0 origin */
+                       if (off > optlen - (int)sizeof(struct in_addr)) {
                                /*
                                 * End of source route.  Should be for us.
                                 */
-                               if (!ip_acceptsourceroute)
+                               if (!ip_acceptsourceroute) {
                                        goto nosourcerouting;
+                               }
                                save_rte(cp, ip->ip_src);
                                break;
                        }
@@ -2135,9 +3403,9 @@ nosourcerouting:
                                            "attempted source route from %s "
                                            "to %s\n",
                                            inet_ntop(AF_INET, &ip->ip_src,
-                                           buf, sizeof (buf)),
+                                           buf, sizeof(buf)),
                                            inet_ntop(AF_INET, &ip->ip_dst,
-                                           buf2, sizeof (buf2)));
+                                           buf2, sizeof(buf2)));
                                        type = ICMP_UNREACH;
                                        code = ICMP_UNREACH_SRCFAIL;
                                        goto bad;
@@ -2148,7 +3416,7 @@ nosourcerouting:
                                         */
                                        OSAddAtomic(1, &ipstat.ips_cantforward);
                                        m_freem(m);
-                                       return (1);
+                                       return 1;
                                }
                        }
 
@@ -2156,12 +3424,12 @@ nosourcerouting:
                         * locate outgoing interface
                         */
                        (void) memcpy(&ipaddr.sin_addr, cp + off,
-                           sizeof (ipaddr.sin_addr));
+                           sizeof(ipaddr.sin_addr));
 
                        if (opt == IPOPT_SSRR) {
-#define        INA     struct in_ifaddr *
+#define INA     struct in_ifaddr *
                                if ((ia = (INA)ifa_ifwithdstaddr(
-                                   SA(&ipaddr))) == NULL) {
+                                           SA(&ipaddr))) == NULL) {
                                        ia = (INA)ifa_ifwithnet(SA(&ipaddr));
                                }
                        } else {
@@ -2175,11 +3443,11 @@ nosourcerouting:
                        ip->ip_dst = ipaddr.sin_addr;
                        IFA_LOCK(&ia->ia_ifa);
                        (void) memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
-                           sizeof (struct in_addr));
+                           sizeof(struct in_addr));
                        IFA_UNLOCK(&ia->ia_ifa);
                        IFA_REMREF(&ia->ia_ifa);
                        ia = NULL;
-                       cp[IPOPT_OFFSET] += sizeof (struct in_addr);
+                       cp[IPOPT_OFFSET] += sizeof(struct in_addr);
                        /*
                         * Let ip_intr's mcast routing check handle mcast pkts
                         */
@@ -2187,7 +3455,7 @@ nosourcerouting:
                        break;
 
                case IPOPT_RR:
-                       if (optlen < IPOPT_OFFSET + sizeof (*cp)) {
+                       if (optlen < IPOPT_OFFSET + sizeof(*cp)) {
                                code = &cp[IPOPT_OFFSET] - (u_char *)ip;
                                goto bad;
                        }
@@ -2198,11 +3466,12 @@ nosourcerouting:
                        /*
                         * If no space remains, ignore.
                         */
-                       off--;                  /* 0 origin */
-                       if (off > optlen - (int)sizeof (struct in_addr))
+                       off--;                  /* 0 origin */
+                       if (off > optlen - (int)sizeof(struct in_addr)) {
                                break;
+                       }
                        (void) memcpy(&ipaddr.sin_addr, &ip->ip_dst,
-                           sizeof (ipaddr.sin_addr));
+                           sizeof(ipaddr.sin_addr));
                        /*
                         * locate outgoing interface; if we're the destination,
                         * use the incoming interface (should be same).
@@ -2216,11 +3485,11 @@ nosourcerouting:
                        }
                        IFA_LOCK(&ia->ia_ifa);
                        (void) memcpy(cp + off, &(IA_SIN(ia)->sin_addr),
-                           sizeof (struct in_addr));
+                           sizeof(struct in_addr));
                        IFA_UNLOCK(&ia->ia_ifa);
                        IFA_REMREF(&ia->ia_ifa);
                        ia = NULL;
-                       cp[IPOPT_OFFSET] += sizeof (struct in_addr);
+                       cp[IPOPT_OFFSET] += sizeof(struct in_addr);
                        break;
 
                case IPOPT_TS:
@@ -2235,7 +3504,7 @@ nosourcerouting:
                                goto bad;
                        }
                        if (ipt->ipt_ptr >
-                           ipt->ipt_len - (int)sizeof (int32_t)) {
+                           ipt->ipt_len - (int)sizeof(int32_t)) {
                                if (++ipt->ipt_oflw == 0) {
                                        code = (u_char *)&ipt->ipt_ptr -
                                            (u_char *)ip;
@@ -2245,13 +3514,12 @@ nosourcerouting:
                        }
                        sin = (struct in_addr *)(void *)(cp + ipt->ipt_ptr - 1);
                        switch (ipt->ipt_flg) {
-
                        case IPOPT_TS_TSONLY:
                                break;
 
                        case IPOPT_TS_TSANDADDR:
-                               if (ipt->ipt_ptr - 1 + sizeof (n_time) +
-                                   sizeof (struct in_addr) > ipt->ipt_len) {
+                               if (ipt->ipt_ptr - 1 + sizeof(n_time) +
+                                   sizeof(struct in_addr) > ipt->ipt_len) {
                                        code = (u_char *)&ipt->ipt_ptr -
                                            (u_char *)ip;
                                        goto bad;
@@ -2259,32 +3527,34 @@ nosourcerouting:
                                ipaddr.sin_addr = dst;
                                ia = (INA)ifaof_ifpforaddr(SA(&ipaddr),
                                    m->m_pkthdr.rcvif);
-                               if (ia == NULL)
+                               if (ia == NULL) {
                                        continue;
+                               }
                                IFA_LOCK(&ia->ia_ifa);
                                (void) memcpy(sin, &IA_SIN(ia)->sin_addr,
-                                   sizeof (struct in_addr));
+                                   sizeof(struct in_addr));
                                IFA_UNLOCK(&ia->ia_ifa);
-                               ipt->ipt_ptr += sizeof (struct in_addr);
+                               ipt->ipt_ptr += sizeof(struct in_addr);
                                IFA_REMREF(&ia->ia_ifa);
                                ia = NULL;
                                break;
 
                        case IPOPT_TS_PRESPEC:
-                               if (ipt->ipt_ptr - 1 + sizeof (n_time) +
-                                   sizeof (struct in_addr) > ipt->ipt_len) {
+                               if (ipt->ipt_ptr - 1 + sizeof(n_time) +
+                                   sizeof(struct in_addr) > ipt->ipt_len) {
                                        code = (u_char *)&ipt->ipt_ptr -
                                            (u_char *)ip;
                                        goto bad;
                                }
                                (void) memcpy(&ipaddr.sin_addr, sin,
-                                   sizeof (struct in_addr));
+                                   sizeof(struct in_addr));
                                if ((ia = (struct in_ifaddr *)ifa_ifwithaddr(
-                                   SA(&ipaddr))) == NULL)
+                                           SA(&ipaddr))) == NULL) {
                                        continue;
+                               }
                                IFA_REMREF(&ia->ia_ifa);
                                ia = NULL;
-                               ipt->ipt_ptr += sizeof (struct in_addr);
+                               ipt->ipt_ptr += sizeof(struct in_addr);
                                break;
 
                        default:
@@ -2295,21 +3565,19 @@ nosourcerouting:
                        }
                        ntime = iptime();
                        (void) memcpy(cp + ipt->ipt_ptr - 1, &ntime,
-                           sizeof (n_time));
-                       ipt->ipt_ptr += sizeof (n_time);
+                           sizeof(n_time));
+                       ipt->ipt_ptr += sizeof(n_time);
                }
        }
        if (forward && ipforwarding) {
                ip_forward(m, 1, next_hop);
-               return (1);
+               return 1;
        }
-       return (0);
+       return 0;
 bad:
-       /* XXX icmp_error adds in hdr length */
-       ip->ip_len -= IP_VHL_HL(ip->ip_vhl) << 2;
        icmp_error(m, type, code, 0, 0);
        OSAddAtomic(1, &ipstat.ips_badoptions);
-       return (1);
+       return 1;
 }
 
 /*
@@ -2337,40 +3605,43 @@ ip_checkrouteralert(struct mbuf *m)
 
        found_ra = 0;
        cp = (u_char *)(ip + 1);
-       cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
+       cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
        for (; cnt > 0; cnt -= optlen, cp += optlen) {
                opt = cp[IPOPT_OPTVAL];
-               if (opt == IPOPT_EOL)
+               if (opt == IPOPT_EOL) {
                        break;
-               if (opt == IPOPT_NOP)
+               }
+               if (opt == IPOPT_NOP) {
                        optlen = 1;
-               else {
+               else {
 #ifdef DIAGNOSTIC
-                       if (cnt < IPOPT_OLEN + sizeof (*cp))
+                       if (cnt < IPOPT_OLEN + sizeof(*cp)) {
                                break;
+                       }
 #endif
                        optlen = cp[IPOPT_OLEN];
 #ifdef DIAGNOSTIC
-                       if (optlen < IPOPT_OLEN + sizeof (*cp) || optlen > cnt)
+                       if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) {
                                break;
+                       }
 #endif
                }
                switch (opt) {
                case IPOPT_RA:
 #ifdef DIAGNOSTIC
-                       if (optlen != IPOPT_OFFSET + sizeof (uint16_t) ||
-                           (*((uint16_t *)(void *)&cp[IPOPT_OFFSET]) != 0))
+                       if (optlen != IPOPT_OFFSET + sizeof(uint16_t) ||
+                           (*((uint16_t *)(void *)&cp[IPOPT_OFFSET]) != 0)) {
                                break;
-                       else
+                       else
 #endif
-                               found_ra = 1;
+                       found_ra = 1;
                        break;
                default:
                        break;
                }
        }
 
-       return (found_ra);
+       return found_ra;
 }
 
 /*
@@ -2384,25 +3655,26 @@ ip_rtaddr(struct in_addr dst)
        struct ifaddr *rt_ifa;
        struct route ro;
 
-       bzero(&ro, sizeof (ro));
+       bzero(&ro, sizeof(ro));
        sin = SIN(&ro.ro_dst);
        sin->sin_family = AF_INET;
-       sin->sin_len = sizeof (*sin);
+       sin->sin_len = sizeof(*sin);
        sin->sin_addr = dst;
 
        rtalloc_ign(&ro, RTF_PRCLONING);
        if (ro.ro_rt == NULL) {
                ROUTE_RELEASE(&ro);
-               return (NULL);
+               return NULL;
        }
 
        RT_LOCK(ro.ro_rt);
-       if ((rt_ifa = ro.ro_rt->rt_ifa) != NULL)
+       if ((rt_ifa = ro.ro_rt->rt_ifa) != NULL) {
                IFA_ADDREF(rt_ifa);
+       }
        RT_UNLOCK(ro.ro_rt);
        ROUTE_RELEASE(&ro);
 
-       return ((struct in_ifaddr *)rt_ifa);
+       return (struct in_ifaddr *)rt_ifa;
 }
 
 /*
@@ -2416,13 +3688,15 @@ save_rte(u_char *option, struct in_addr dst)
 
        olen = option[IPOPT_OLEN];
 #if DIAGNOSTIC
-       if (ipprintfs)
+       if (ipprintfs) {
                printf("save_rte: olen %d\n", olen);
+       }
 #endif
-       if (olen > sizeof (ip_srcrt) - (1 + sizeof (dst)))
+       if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) {
                return;
+       }
        bcopy(option, ip_srcrt.srcopt, olen);
-       ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof (struct in_addr);
+       ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr);
        ip_srcrt.dst = dst;
 }
 
@@ -2437,21 +3711,24 @@ ip_srcroute(void)
        struct in_addr *p, *q;
        struct mbuf *m;
 
-       if (ip_nhops == 0)
-               return (NULL);
+       if (ip_nhops == 0) {
+               return NULL;
+       }
 
        m = m_get(M_DONTWAIT, MT_HEADER);
-       if (m == NULL)
-               return (NULL);
+       if (m == NULL) {
+               return NULL;
+       }
 
-#define        OPTSIZ  (sizeof (ip_srcrt.nop) + sizeof (ip_srcrt.srcopt))
+#define OPTSIZ  (sizeof (ip_srcrt.nop) + sizeof (ip_srcrt.srcopt))
 
        /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */
-       m->m_len = ip_nhops * sizeof (struct in_addr) +
-           sizeof (struct in_addr) + OPTSIZ;
+       m->m_len = ip_nhops * sizeof(struct in_addr) +
+           sizeof(struct in_addr) + OPTSIZ;
 #if DIAGNOSTIC
-       if (ipprintfs)
+       if (ipprintfs) {
                printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len);
+       }
 #endif
 
        /*
@@ -2460,9 +3737,10 @@ ip_srcroute(void)
        p = &ip_srcrt.route[ip_nhops - 1];
        *(mtod(m, struct in_addr *)) = *p--;
 #if DIAGNOSTIC
-       if (ipprintfs)
+       if (ipprintfs) {
                printf(" hops %lx",
                    (u_int32_t)ntohl(mtod(m, struct in_addr *)->s_addr));
+       }
 #endif
 
        /*
@@ -2470,10 +3748,10 @@ ip_srcroute(void)
         */
        ip_srcrt.nop = IPOPT_NOP;
        ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF;
-       (void) memcpy(mtod(m, caddr_t) + sizeof (struct in_addr),
+       (void) memcpy(mtod(m, caddr_t) + sizeof(struct in_addr),
            &ip_srcrt.nop, OPTSIZ);
        q = (struct in_addr *)(void *)(mtod(m, caddr_t) +
-           sizeof (struct in_addr) + OPTSIZ);
+           sizeof(struct in_addr) + OPTSIZ);
 #undef OPTSIZ
        /*
         * Record return path as an IP source route,
@@ -2481,8 +3759,9 @@ ip_srcroute(void)
         */
        while (p >= ip_srcrt.route) {
 #if DIAGNOSTIC
-               if (ipprintfs)
+               if (ipprintfs) {
                        printf(" %lx", (u_int32_t)ntohl(q->s_addr));
+               }
 #endif
                *q++ = *p--;
        }
@@ -2491,23 +3770,19 @@ ip_srcroute(void)
         */
        *q = ip_srcrt.dst;
 #if DIAGNOSTIC
-       if (ipprintfs)
+       if (ipprintfs) {
                printf(" %lx\n", (u_int32_t)ntohl(q->s_addr));
+       }
 #endif
-       return (m);
+       return m;
 }
 
 /*
- * Strip out IP options, at higher
- * level protocol in the kernel.
- * Second argument is buffer to which options
- * will be moved, and return value is their length.
- * XXX should be deleted; last arg currently ignored.
+ * Strip out IP options, at higher level protocol in the kernel.
  */
 void
-ip_stripoptions(struct mbuf *m, struct mbuf *mopt)
+ip_stripoptions(struct mbuf *m)
 {
-#pragma unused(mopt)
        int i;
        struct ip *ip = mtod(m, struct ip *);
        caddr_t opts;
@@ -2516,23 +3791,46 @@ ip_stripoptions(struct mbuf *m, struct mbuf *mopt)
        /* Expect 32-bit aligned data pointer on strict-align platforms */
        MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
 
-       olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip);
+       /* use bcopy() since it supports overlapping range */
+       olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
        opts = (caddr_t)(ip + 1);
-       i = m->m_len - (sizeof (struct ip) + olen);
+       i = m->m_len - (sizeof(struct ip) + olen);
        bcopy(opts + olen, opts, (unsigned)i);
        m->m_len -= olen;
-       if (m->m_flags & M_PKTHDR)
+       if (m->m_flags & M_PKTHDR) {
                m->m_pkthdr.len -= olen;
-       ip->ip_vhl = IP_MAKE_VHL(IPVERSION, sizeof (struct ip) >> 2);
+       }
+       ip->ip_vhl = IP_MAKE_VHL(IPVERSION, sizeof(struct ip) >> 2);
+
+       /*
+        * We expect ip_{off,len} to be in host order by now, and
+        * that the original IP header length has been subtracted
+        * out from ip_len.  Temporarily adjust ip_len for checksum
+        * recalculation, and restore it afterwards.
+        */
+       ip->ip_len += sizeof(struct ip);
+
+       /* recompute checksum now that IP header is smaller */
+#if BYTE_ORDER != BIG_ENDIAN
+       HTONS(ip->ip_len);
+       HTONS(ip->ip_off);
+#endif /* BYTE_ORDER != BIG_ENDIAN */
+       ip->ip_sum = in_cksum_hdr(ip);
+#if BYTE_ORDER != BIG_ENDIAN
+       NTOHS(ip->ip_off);
+       NTOHS(ip->ip_len);
+#endif /* BYTE_ORDER != BIG_ENDIAN */
+
+       ip->ip_len -= sizeof(struct ip);
 }
 
 u_char inetctlerrmap[PRC_NCMDS] = {
-       0,              0,              0,              0,
-       0,              EMSGSIZE,       EHOSTDOWN,      EHOSTUNREACH,
-       ENETUNREACH,    EHOSTUNREACH,   ECONNREFUSED,   ECONNREFUSED,
-       EMSGSIZE,       EHOSTUNREACH,   0,              0,
-       0,              0,              0,              0,
-       ENOPROTOOPT,    ECONNREFUSED
+       0, 0, 0, 0,
+       0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
+       ENETUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
+       EMSGSIZE, EHOSTUNREACH, 0, 0,
+       0, 0, 0, 0,
+       ENOPROTOOPT, ECONNREFUSED
 };
 
 static int
@@ -2542,8 +3840,9 @@ sysctl_ipforwarding SYSCTL_HANDLER_ARGS
        int i, was_ipforwarding = ipforwarding;
 
        i = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
-       if (i != 0 || req->newptr == USER_ADDR_NULL)
-               return (i);
+       if (i != 0 || req->newptr == USER_ADDR_NULL) {
+               return i;
+       }
 
        if (was_ipforwarding && !ipforwarding) {
                /* clean up IPv4 forwarding cached routes */
@@ -2554,14 +3853,14 @@ sysctl_ipforwarding SYSCTL_HANDLER_ARGS
                                lck_mtx_lock(&ifp->if_cached_route_lock);
                                ROUTE_RELEASE(&ifp->if_fwd_route);
                                bzero(&ifp->if_fwd_route,
-                                   sizeof (ifp->if_fwd_route));
+                                   sizeof(ifp->if_fwd_route));
                                lck_mtx_unlock(&ifp->if_cached_route_lock);
                        }
                }
                ifnet_head_done();
        }
 
-       return (0);
+       return 0;
 }
 
 /*
@@ -2578,10 +3877,11 @@ ip_fwd_route_copyout(struct ifnet *ifp, struct route *dst)
        lck_mtx_convert_spin(&ifp->if_cached_route_lock);
 
        /* Minor sanity check */
-       if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET)
+       if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET) {
                panic("%s: wrong or corrupted route: %p", __func__, src);
+       }
 
-       route_copyout(dst, src, sizeof (*dst));
+       route_copyout(dst, src, sizeof(*dst));
 
        lck_mtx_unlock(&ifp->if_cached_route_lock);
 }
@@ -2595,11 +3895,13 @@ ip_fwd_route_copyin(struct ifnet *ifp, struct route *src)
        lck_mtx_convert_spin(&ifp->if_cached_route_lock);
 
        /* Minor sanity check */
-       if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET)
+       if (src->ro_rt != NULL && rt_key(src->ro_rt)->sa_family != AF_INET) {
                panic("%s: wrong or corrupted route: %p", __func__, src);
+       }
 
-       if (ifp->if_fwd_cacheok)
-               route_copyin(src, dst, sizeof (*src));
+       if (ifp->if_fwd_cacheok) {
+               route_copyin(src, dst, sizeof(*src));
+       }
 
        lck_mtx_unlock(&ifp->if_cached_route_lock);
 }
@@ -2633,8 +3935,14 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
        n_long dest;
        struct in_addr pkt_dst;
        u_int32_t nextmtu = 0, len;
-       struct ip_out_args ipoa = { IFSCOPE_NONE, { 0 }, 0, 0 };
+       struct ip_out_args ipoa;
        struct ifnet *rcvifp = m->m_pkthdr.rcvif;
+
+       bzero(&ipoa, sizeof(ipoa));
+       ipoa.ipoa_boundif = IFSCOPE_NONE;
+       ipoa.ipoa_sotc = SO_TC_UNSPEC;
+       ipoa.ipoa_netsvctype = _NET_SERVICE_TYPE_UNSPEC;
+
 #if IPSEC
        struct secpolicy *sp = NULL;
        int ipsecerror;
@@ -2655,13 +3963,14 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
 #endif /* !IPFIREWALL */
 
 #if DIAGNOSTIC
-       if (ipprintfs)
+       if (ipprintfs) {
                printf("forward: src %lx dst %lx ttl %x\n",
                    (u_int32_t)ip->ip_src.s_addr, (u_int32_t)pkt_dst.s_addr,
                    ip->ip_ttl);
+       }
 #endif
 
-       if (m->m_flags & (M_BCAST|M_MCAST) || !in_canforward(pkt_dst)) {
+       if (m->m_flags & (M_BCAST | M_MCAST) || !in_canforward(pkt_dst)) {
                OSAddAtomic(1, &ipstat.ips_cantforward);
                m_freem(m);
                return;
@@ -2669,13 +3978,13 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
 #if IPSTEALTH
        if (!ipstealth) {
 #endif /* IPSTEALTH */
-               if (ip->ip_ttl <= IPTTLDEC) {
-                       icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS,
-                           dest, 0);
-                       return;
-               }
-#if IPSTEALTH
+       if (ip->ip_ttl <= IPTTLDEC) {
+               icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS,
+                   dest, 0);
+               return;
        }
+#if IPSTEALTH
+}
 #endif /* IPSTEALTH */
 
 #if PF
@@ -2693,7 +4002,7 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                ROUTE_RELEASE(&fwd_rt);
 
                sin->sin_family = AF_INET;
-               sin->sin_len = sizeof (*sin);
+               sin->sin_len = sizeof(*sin);
                sin->sin_addr = pkt_dst;
 
                rtalloc_scoped_ign(&fwd_rt, RTF_PRCLONING, ipoa.ipoa_boundif);
@@ -2724,9 +4033,9 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
 #if IPSTEALTH
        if (!ipstealth) {
 #endif /* IPSTEALTH */
-               ip->ip_ttl -= IPTTLDEC;
+       ip->ip_ttl -= IPTTLDEC;
 #if IPSTEALTH
-       }
+}
 #endif /* IPSTEALTH */
 
        /*
@@ -2739,7 +4048,7 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
         */
        RT_LOCK_SPIN(rt);
        if (rt->rt_ifp == m->m_pkthdr.rcvif &&
-           !(rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) &&
+           !(rt->rt_flags & (RTF_DYNAMIC | RTF_MODIFIED)) &&
            satosin(rt_key(rt))->sin_addr.s_addr != INADDR_ANY &&
            ipsendredirects && !srcrt && rt->rt_ifa != NULL) {
                struct in_ifaddr *ia = (struct in_ifaddr *)rt->rt_ifa;
@@ -2749,10 +4058,11 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                RT_CONVERT_LOCK(rt);
                IFA_LOCK_SPIN(&ia->ia_ifa);
                if ((src & ia->ia_subnetmask) == ia->ia_subnet) {
-                       if (rt->rt_flags & RTF_GATEWAY)
+                       if (rt->rt_flags & RTF_GATEWAY) {
                                dest = satosin(rt->rt_gateway)->sin_addr.s_addr;
-                       else
+                       } else {
                                dest = pkt_dst.s_addr;
+                       }
                        /*
                         * Router requirements says to only send
                         * host redirects.
@@ -2760,9 +4070,10 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                        type = ICMP_REDIRECT;
                        code = ICMP_REDIRECT_HOST;
 #if DIAGNOSTIC
-                       if (ipprintfs)
+                       if (ipprintfs) {
                                printf("redirect (%d) to %lx\n", code,
                                    (u_int32_t)dest);
+                       }
 #endif
                }
                IFA_UNLOCK(&ia->ia_ifa);
@@ -2777,14 +4088,14 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
 
                tag = m_tag_create(KERNEL_MODULE_TAG_ID,
                    KERNEL_TAG_TYPE_IPFORWARD,
-                   sizeof (*ipfwd_tag), M_NOWAIT, m);
+                   sizeof(*ipfwd_tag), M_NOWAIT, m);
                if (tag == NULL) {
                        error = ENOBUFS;
                        m_freem(m);
                        goto done;
                }
 
-               ipfwd_tag = (struct ip_fwd_tag *)(tag+1);
+               ipfwd_tag = (struct ip_fwd_tag *)(tag + 1);
                ipfwd_tag->next_hop = next_hop;
 
                m_tag_prepend(m, tag);
@@ -2828,15 +4139,16 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                        goto done;
                }
        }
-       if (mcopy == NULL)
+       if (mcopy == NULL) {
                goto done;
+       }
 
        switch (error) {
-       case 0:                         /* forwarded, but need redirect */
+       case 0:                         /* forwarded, but need redirect */
                /* type, code set above */
                break;
 
-       case ENETUNREACH:               /* shouldn't happen, checked above */
+       case ENETUNREACH:               /* shouldn't happen, checked above */
        case EHOSTUNREACH:
        case ENETDOWN:
        case EHOSTDOWN:
@@ -2853,13 +4165,15 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                        break;
                } else {
                        RT_LOCK_SPIN(rt);
-                       if (rt->rt_ifp != NULL)
+                       if (rt->rt_ifp != NULL) {
                                nextmtu = rt->rt_ifp->if_mtu;
+                       }
                        RT_UNLOCK(rt);
                }
 #ifdef IPSEC
-               if (ipsec_bypass)
+               if (ipsec_bypass) {
                        break;
+               }
 
                /*
                 * If the packet is routed over IPsec tunnel, tell the
@@ -2870,8 +4184,9 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                sp = ipsec4_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND,
                    IP_FORWARDING, &ipsecerror);
 
-               if (sp == NULL)
+               if (sp == NULL) {
                        break;
+               }
 
                /*
                 * find the correct route for outer IPv4
@@ -2891,30 +4206,30 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                        ipsechdr = ipsec_hdrsiz(sp);
 
                        ipm = mtod(mcopy, struct ip *);
-                       bcopy(&sp->req->saidx, &saidx, sizeof (saidx));
+                       bcopy(&sp->req->saidx, &saidx, sizeof(saidx));
                        saidx.mode = sp->req->saidx.mode;
                        saidx.reqid = sp->req->saidx.reqid;
                        sin = SIN(&saidx.src);
                        if (sin->sin_len == 0) {
-                               sin->sin_len = sizeof (*sin);
+                               sin->sin_len = sizeof(*sin);
                                sin->sin_family = AF_INET;
                                sin->sin_port = IPSEC_PORT_ANY;
                                bcopy(&ipm->ip_src, &sin->sin_addr,
-                                   sizeof (sin->sin_addr));
+                                   sizeof(sin->sin_addr));
                        }
                        sin = SIN(&saidx.dst);
                        if (sin->sin_len == 0) {
-                               sin->sin_len = sizeof (*sin);
+                               sin->sin_len = sizeof(*sin);
                                sin->sin_family = AF_INET;
                                sin->sin_port = IPSEC_PORT_ANY;
                                bcopy(&ipm->ip_dst, &sin->sin_addr,
-                                   sizeof (sin->sin_addr));
+                                   sizeof(sin->sin_addr));
                        }
                        sav = key_allocsa_policy(&saidx);
                        if (sav != NULL) {
                                lck_mtx_lock(sadb_mutex);
                                if (sav->sah != NULL) {
-                                       ro = &sav->sah->sa_route;
+                                       ro = (struct route *)&sav->sah->sa_route;
                                        if (ro->ro_rt != NULL) {
                                                RT_LOCK(ro->ro_rt);
                                                if (ro->ro_rt->rt_ifp != NULL) {
@@ -2951,13 +4266,14 @@ ip_forward(struct mbuf *m, int srcrt, struct sockaddr_in *next_hop)
                }
                break;
 
-       case EACCES:                    /* ipfw denied packet */
+       case EACCES:                    /* ipfw denied packet */
                m_freem(mcopy);
                goto done;
        }
 
-       if (type == ICMP_UNREACH && code == ICMP_UNREACH_NEEDFRAG)
+       if (type == ICMP_UNREACH && code == ICMP_UNREACH_NEEDFRAG) {
                OSAddAtomic(1, &ipstat.ips_cantfrag);
+       }
 
        icmp_error(mcopy, type, code, dest, nextmtu);
 done:
@@ -2973,7 +4289,7 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
                struct timeval tv;
 
                getmicrotime(&tv);
-               mp = sbcreatecontrol_mbuf((caddr_t)&tv, sizeof (tv),
+               mp = sbcreatecontrol_mbuf((caddr_t)&tv, sizeof(tv),
                    SCM_TIMESTAMP, SOL_SOCKET, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
@@ -2983,15 +4299,25 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
                uint64_t time;
 
                time = mach_absolute_time();
-               mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof (time),
+               mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time),
                    SCM_TIMESTAMP_MONOTONIC, SOL_SOCKET, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
                }
        }
+       if (inp->inp_socket->so_options & SO_TIMESTAMP_CONTINUOUS) {
+               uint64_t time;
+
+               time = mach_continuous_time();
+               mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time),
+                   SCM_TIMESTAMP_CONTINUOUS, SOL_SOCKET, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
+       }
        if (inp->inp_flags & INP_RECVDSTADDR) {
                mp = sbcreatecontrol_mbuf((caddr_t)&ip->ip_dst,
-                   sizeof (struct in_addr), IP_RECVDSTADDR, IPPROTO_IP, mp);
+                   sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
                }
@@ -3005,7 +4331,7 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
        /* options were tossed already */
        if (inp->inp_flags & INP_RECVOPTS) {
                mp = sbcreatecontrol_mbuf((caddr_t)opts_deleted_above,
-                   sizeof (struct in_addr), IP_RECVOPTS, IPPROTO_IP, mp);
+                   sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
                }
@@ -3013,7 +4339,7 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
        /* ip_srcroute doesn't do what we want here, need to fix */
        if (inp->inp_flags & INP_RECVRETOPTS) {
                mp = sbcreatecontrol_mbuf((caddr_t)ip_srcroute(),
-                   sizeof (struct in_addr), IP_RECVRETOPTS, IPPROTO_IP, mp);
+                   sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
                }
@@ -3028,7 +4354,7 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
                 * Make sure to accomodate the largest possible
                 * size of SA(if_lladdr)->sa_len.
                 */
-               _CASSERT(sizeof (sdlbuf) == (SOCK_MAXADDRLEN + 1));
+               _CASSERT(sizeof(sdlbuf) == (SOCK_MAXADDRLEN + 1));
 
                ifnet_head_lock_shared();
                if ((ifp = m->m_pkthdr.rcvif) != NULL &&
@@ -3036,8 +4362,9 @@ ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
                        struct ifaddr *ifa = ifnet_addrs[ifp->if_index - 1];
                        struct sockaddr_dl *sdp;
 
-                       if (!ifa || !ifa->ifa_addr)
+                       if (!ifa || !ifa->ifa_addr) {
                                goto makedummy;
+                       }
 
                        IFA_LOCK_SPIN(ifa);
                        sdp = SDL(ifa->ifa_addr);
@@ -3068,7 +4395,7 @@ makedummy:
        }
        if (inp->inp_flags & INP_RECVTTL) {
                mp = sbcreatecontrol_mbuf((caddr_t)&ip->ip_ttl,
-                   sizeof (ip->ip_ttl), IP_RECVTTL, IPPROTO_IP, mp);
+                   sizeof(ip->ip_ttl), IP_RECVTTL, IPPROTO_IP, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
                }
@@ -3076,7 +4403,7 @@ makedummy:
        if (inp->inp_socket->so_flags & SOF_RECV_TRAFFIC_CLASS) {
                int tc = m_get_traffic_class(m);
 
-               mp = sbcreatecontrol_mbuf((caddr_t)&tc, sizeof (tc),
+               mp = sbcreatecontrol_mbuf((caddr_t)&tc, sizeof(tc),
                    SO_TRAFFIC_CLASS, SOL_SOCKET, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
@@ -3085,22 +4412,29 @@ makedummy:
        if (inp->inp_flags & INP_PKTINFO) {
                struct in_pktinfo pi;
 
-               bzero(&pi, sizeof (struct in_pktinfo));
-               bcopy(&ip->ip_dst, &pi.ipi_addr, sizeof (struct in_addr));
+               bzero(&pi, sizeof(struct in_pktinfo));
+               bcopy(&ip->ip_dst, &pi.ipi_addr, sizeof(struct in_addr));
                pi.ipi_ifindex = (m != NULL && m->m_pkthdr.rcvif != NULL) ?
                    m->m_pkthdr.rcvif->if_index : 0;
 
                mp = sbcreatecontrol_mbuf((caddr_t)&pi,
-                   sizeof (struct in_pktinfo), IP_RECVPKTINFO, IPPROTO_IP, mp);
+                   sizeof(struct in_pktinfo), IP_RECVPKTINFO, IPPROTO_IP, mp);
+               if (*mp == NULL) {
+                       goto no_mbufs;
+               }
+       }
+       if (inp->inp_flags & INP_RECVTOS) {
+               mp = sbcreatecontrol_mbuf((caddr_t)&ip->ip_tos,
+                   sizeof(u_char), IP_RECVTOS, IPPROTO_IP, mp);
                if (*mp == NULL) {
                        goto no_mbufs;
                }
        }
-       return (0);
+       return 0;
 
 no_mbufs:
        ipstat.ips_pktdropcntrl++;
-       return (ENOBUFS);
+       return ENOBUFS;
 }
 
 static inline u_short
@@ -3124,20 +4458,22 @@ ip_cksum(struct mbuf *m, int hlen)
                m->m_pkthdr.csum_data = 0xffff;
        }
 
-       if (sum != 0)
+       if (sum != 0) {
                OSAddAtomic(1, &ipstat.ips_badsum);
+       }
 
-       return (sum);
+       return sum;
 }
 
 static int
 ip_getstat SYSCTL_HANDLER_ARGS
 {
 #pragma unused(oidp, arg1, arg2)
-       if (req->oldptr == USER_ADDR_NULL)
-               req->oldlen = (size_t)sizeof (struct ipstat);
+       if (req->oldptr == USER_ADDR_NULL) {
+               req->oldlen = (size_t)sizeof(struct ipstat);
+       }
 
-       return (SYSCTL_OUT(req, &ipstat, MIN(sizeof (ipstat), req->oldlen)));
+       return SYSCTL_OUT(req, &ipstat, MIN(sizeof(ipstat), req->oldlen));
 }
 
 void
@@ -3155,8 +4491,9 @@ ip_setsrcifaddr_info(struct mbuf *m, uint32_t src_idx, struct in_ifaddr *ia)
                m->m_pkthdr.src_ifindex = ia->ia_ifp->if_index;
        } else {
                m->m_pkthdr.src_ifindex = src_idx;
-               if (src_idx != 0)
+               if (src_idx != 0) {
                        m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
+               }
        }
 }
 
@@ -3175,8 +4512,9 @@ ip_setdstifaddr_info(struct mbuf *m, uint32_t dst_idx, struct in_ifaddr *ia)
                m->m_pkthdr.dst_ifindex = ia->ia_ifp->if_index;
        } else {
                m->m_pkthdr.dst_ifindex = dst_idx;
-               if (dst_idx != 0)
+               if (dst_idx != 0) {
                        m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
+               }
        }
 }
 
@@ -3185,16 +4523,19 @@ ip_getsrcifaddr_info(struct mbuf *m, uint32_t *src_idx, uint32_t *iaf)
 {
        VERIFY(m->m_flags & M_PKTHDR);
 
-       if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO))
-               return (-1);
+       if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) {
+               return -1;
+       }
 
-       if (src_idx != NULL)
+       if (src_idx != NULL) {
                *src_idx = m->m_pkthdr.src_ifindex;
+       }
 
-       if (iaf != NULL)
+       if (iaf != NULL) {
                *iaf = 0;
+       }
 
-       return (0);
+       return 0;
 }
 
 int
@@ -3202,16 +4543,19 @@ ip_getdstifaddr_info(struct mbuf *m, uint32_t *dst_idx, uint32_t *iaf)
 {
        VERIFY(m->m_flags & M_PKTHDR);
 
-       if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO))
-               return (-1);
+       if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) {
+               return -1;
+       }
 
-       if (dst_idx != NULL)
+       if (dst_idx != NULL) {
                *dst_idx = m->m_pkthdr.dst_ifindex;
+       }
 
-       if (iaf != NULL)
+       if (iaf != NULL) {
                *iaf = 0;
+       }
 
-       return (0);
+       return 0;
 }
 
 /*
@@ -3235,8 +4579,9 @@ gre_input(struct mbuf *m, int off)
         * If no matching tunnel that is up is found, we inject
         * the mbuf to raw ip socket to see if anyone picks it up.
         */
-       if (m != NULL)
+       if (m != NULL) {
                rip_input(m, off);
+       }
 }
 
 /*
@@ -3249,5 +4594,64 @@ ip_gre_register_input(gre_input_func_t fn)
        gre_input_func = fn;
        lck_mtx_unlock(inet_domain_mutex);
 
-       return (0);
+       return 0;
+}
+
+#if (DEBUG || DEVELOPMENT)
+static int
+sysctl_reset_ip_input_stats SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+       int error, i;
+
+       i = ip_input_measure;
+       error = sysctl_handle_int(oidp, &i, 0, req);
+       if (error || req->newptr == USER_ADDR_NULL) {
+               goto done;
+       }
+       /* impose bounds */
+       if (i < 0 || i > 1) {
+               error = EINVAL;
+               goto done;
+       }
+       if (ip_input_measure != i && i == 1) {
+               net_perf_initialize(&net_perf, ip_input_measure_bins);
+       }
+       ip_input_measure = i;
+done:
+       return error;
+}
+
+static int
+sysctl_ip_input_measure_bins SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+       int error;
+       uint64_t i;
+
+       i = ip_input_measure_bins;
+       error = sysctl_handle_quad(oidp, &i, 0, req);
+       if (error || req->newptr == USER_ADDR_NULL) {
+               goto done;
+       }
+       /* validate data */
+       if (!net_perf_validate_bins(i)) {
+               error = EINVAL;
+               goto done;
+       }
+       ip_input_measure_bins = i;
+done:
+       return error;
+}
+
+static int
+sysctl_ip_input_getperf SYSCTL_HANDLER_ARGS
+{
+#pragma unused(oidp, arg1, arg2)
+       if (req->oldptr == USER_ADDR_NULL) {
+               req->oldlen = (size_t)sizeof(struct ipstat);
+       }
+
+       return SYSCTL_OUT(req, &net_perf, MIN(sizeof(net_perf), req->oldlen));
 }
+#endif /* (DEBUG || DEVELOPMENT) */