xnu-792.1.5.tar.gz

[apple/xnu.git] / bsd / netinet / tcp_timer.c

diff --git a/bsd/netinet/tcp_timer.c b/bsd/netinet/tcp_timer.c
index 3d92a0d8203ff8a04d31262e820ab52a182055ab..b3c5388b92a5c8cc54b1e5f4b243dea97fc363a3 100644 (file)
--- a/bsd/netinet/tcp_timer.c
+++ b/bsd/netinet/tcp_timer.c
@@ -3,22 +3,19 @@
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
  *
  * @APPLE_LICENSE_HEADER_START@
  * 

- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License").  You may not use this file except in compliance with the
+ * License.  Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.

  * 
  * 

- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- * 
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER

  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.

  * 
  * @APPLE_LICENSE_HEADER_END@
  */
  * 
  * @APPLE_LICENSE_HEADER_END@
  */


@@ -67,6 +64,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/protosw.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/protosw.h>

+#include <kern/locks.h>

 
 #include <kern/cpu_number.h>   /* before tcp_seq.h, for tcp_random18() */
 
 
 #include <kern/cpu_number.h>   /* before tcp_seq.h, for tcp_random18() */
 


@@ -93,6 +91,13 @@
 #define DBG_FNC_TCP_FAST       NETDBG_CODE(DBG_NETTCP, (5 << 8))
 #define DBG_FNC_TCP_SLOW       NETDBG_CODE(DBG_NETTCP, (5 << 8) | 1)
 
 #define DBG_FNC_TCP_FAST       NETDBG_CODE(DBG_NETTCP, (5 << 8))
 #define DBG_FNC_TCP_SLOW       NETDBG_CODE(DBG_NETTCP, (5 << 8) | 1)
 

+/*
+ * NOTE - WARNING
+ *
+ *
+ * 
+ *
+ */

 static int
 sysctl_msec_to_ticks SYSCTL_HANDLER_ARGS
 {
 static int
 sysctl_msec_to_ticks SYSCTL_HANDLER_ARGS
 {


@@ -150,11 +155,16 @@ int               cur_tw_slot = 0;
 u_long         *delack_bitmask;
 
 
 u_long         *delack_bitmask;
 
 

-void   add_to_time_wait(tp) 
+void   add_to_time_wait_locked(tp) 

        struct tcpcb    *tp;
 {
        int             tw_slot;
 
        struct tcpcb    *tp;
 {
        int             tw_slot;
 

+       /* pcb list should be locked when we get here */        
+#if 0
+       lck_mtx_assert(tp->t_inpcb->inpcb_mtx, LCK_MTX_ASSERT_OWNED);
+#endif
+

        LIST_REMOVE(tp->t_inpcb, inp_list);
 
        if (tp->t_timer[TCPT_2MSL] == 0) 
        LIST_REMOVE(tp->t_inpcb, inp_list);
 
        if (tp->t_timer[TCPT_2MSL] == 0) 


@@ -168,6 +178,19 @@ void       add_to_time_wait(tp)
        LIST_INSERT_HEAD(&time_wait_slots[tw_slot], tp->t_inpcb, inp_list);
 }
 
        LIST_INSERT_HEAD(&time_wait_slots[tw_slot], tp->t_inpcb, inp_list);
 }
 

+void   add_to_time_wait(tp) 
+       struct tcpcb    *tp;
+{
+       struct inpcbinfo *pcbinfo               = &tcbinfo;
+       
+       if (!lck_rw_try_lock_exclusive(pcbinfo->mtx)) {
+               tcp_unlock(tp->t_inpcb->inp_socket, 0, 0);
+               lck_rw_lock_exclusive(pcbinfo->mtx);
+               tcp_lock(tp->t_inpcb->inp_socket, 0, 0);
+       }
+       add_to_time_wait_locked(tp);
+       lck_rw_done(pcbinfo->mtx);
+}

 
 
 
 
 
 


@@ -178,49 +201,46 @@ void      add_to_time_wait(tp)
 void
 tcp_fasttimo()
 {
 void
 tcp_fasttimo()
 {

-    register struct inpcb *inp;
+    struct inpcb *inp, *inpnxt;

     register struct tcpcb *tp;
 
 
     register struct tcpcb *tp;
 
 

-    register u_long                    i,j;
-    register u_long                    temp_mask;
-    register u_long                    elem_base = 0;
-    struct inpcbhead                   *head;
-    int s = splnet();
+    struct inpcbinfo *pcbinfo  = &tcbinfo;

 
 

-    static
-    int delack_checked = 0;
+    int delack_checked = 0, delack_done = 0;

 
     KERNEL_DEBUG(DBG_FNC_TCP_FAST | DBG_FUNC_START, 0,0,0,0,0);
 
 
     KERNEL_DEBUG(DBG_FNC_TCP_FAST | DBG_FUNC_START, 0,0,0,0,0);
 

-    if (!tcp_delack_enabled) 
+    if (tcp_delack_enabled == 0) 

        return;
 
        return;
 

-    for (i=0; i < (tcbinfo.hashsize / 32); i++) {
-           if (delack_bitmask[i]) {
-               temp_mask = 1;
-               for (j=0; j < 32; j++) {
-                   if (temp_mask & delack_bitmask[i]) {
-                       head = &tcbinfo.hashbase[elem_base + j];
-                       for (inp=head->lh_first; inp != 0; inp = inp->inp_hash.le_next) {
-                           delack_checked++;
-                           if ((tp = (struct tcpcb *)inp->inp_ppcb) && (tp->t_flags & TF_DELACK)) {
-                               tp->t_flags &= ~TF_DELACK;
-                               tp->t_flags |= TF_ACKNOW;
-                               tcpstat.tcps_delack++;
-                               (void) tcp_output(tp);
-                           }
-                       }
-                   }
-                   temp_mask <<=  1;
+    lck_rw_lock_shared(pcbinfo->mtx);
+
+    /* Walk the list of valid tcpcbs and send ACKS on the ones with DELACK bit set */
+
+    for (inp = tcb.lh_first; inp != NULL; inp = inpnxt) {
+       inpnxt = inp->inp_list.le_next;
+       /* NOTE: it's OK to check the tp because the pcb can't be removed while we hold pcbinfo->mtx) */
+       if ((tp = (struct tcpcb *)inp->inp_ppcb) && (tp->t_flags & TF_DELACK)) {
+               if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) 
+                       continue;
+               tcp_lock(inp->inp_socket, 1, 0);
+               if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) {
+                       tcp_unlock(inp->inp_socket, 1, 0);
+                       continue;
+               }
+               if (tp->t_flags & TF_DELACK) {
+                       delack_done++;
+                       tp->t_flags &= ~TF_DELACK;
+                       tp->t_flags |= TF_ACKNOW;
+                       tcpstat.tcps_delack++;
+                       (void) tcp_output(tp);

                }
                }

-               delack_bitmask[i] = 0;
-           }
-           elem_base += 32;
+               tcp_unlock(inp->inp_socket, 1, 0);
+       }

     }
     }

-    KERNEL_DEBUG(DBG_FNC_TCP_FAST | DBG_FUNC_END, delack_checked,tcpstat.tcps_delack,0,0,0);
-    splx(s);
-
+    KERNEL_DEBUG(DBG_FNC_TCP_FAST | DBG_FUNC_END, delack_checked, delack_done, tcpstat.tcps_delack,0,0);
+    lck_rw_done(pcbinfo->mtx);

 }
 
 /*
 }
 
 /*


@@ -231,41 +251,54 @@ tcp_fasttimo()
 void
 tcp_slowtimo()
 {
 void
 tcp_slowtimo()
 {

-       register struct inpcb *ip, *ipnxt;
-       register struct tcpcb *tp;
-       register int i;
-       int s;
+       struct inpcb *inp, *inpnxt;
+       struct tcpcb *tp;
+       struct socket *so;
+       int i;

 #if TCPDEBUG
        int ostate;
 #endif
 #if KDEBUG
        static int tws_checked;
 #endif
 #if TCPDEBUG
        int ostate;
 #endif
 #if KDEBUG
        static int tws_checked;
 #endif

+       struct inpcbinfo *pcbinfo               = &tcbinfo;

 
        KERNEL_DEBUG(DBG_FNC_TCP_SLOW | DBG_FUNC_START, 0,0,0,0,0);
 
        KERNEL_DEBUG(DBG_FNC_TCP_SLOW | DBG_FUNC_START, 0,0,0,0,0);

-       s = splnet();

 
        tcp_maxidle = tcp_keepcnt * tcp_keepintvl;
 
 
        tcp_maxidle = tcp_keepcnt * tcp_keepintvl;
 

-       ip = tcb.lh_first;
-       if (ip == NULL) {
-               splx(s);
-               return;
-       }
+       lck_rw_lock_shared(pcbinfo->mtx);
+

        /*
         * Search through tcb's and update active timers.
         */
        /*
         * Search through tcb's and update active timers.
         */

-       for (; ip != NULL; ip = ipnxt) {
-               ipnxt = ip->inp_list.le_next;
-               tp = intotcpcb(ip);
-               if (tp == 0 || tp->t_state == TCPS_LISTEN)
+       for (inp = tcb.lh_first; inp != NULL; inp = inpnxt) {
+               inpnxt = inp->inp_list.le_next;
+
+               if (in_pcb_checkstate(inp, WNT_ACQUIRE,0) == WNT_STOPUSING) 
+                       continue;
+
+               so = inp->inp_socket;
+               tcp_lock(so, 1, 0);
+
+               if ((in_pcb_checkstate(inp, WNT_RELEASE,1) == WNT_STOPUSING)  && so->so_usecount == 1) {
+                       tcp_unlock(so, 1, 0);

                        continue;
                        continue;

+               }
+               tp = intotcpcb(inp);
+               if (tp == 0 || tp->t_state == TCPS_LISTEN) {
+                       tcp_unlock(so, 1, 0);
+                       continue; 
+               }

                /*
                 * Bogus state when port owned by SharedIP with loopback as the
                 * only configured interface: BlueBox does not filters loopback
                 */
                /*
                 * Bogus state when port owned by SharedIP with loopback as the
                 * only configured interface: BlueBox does not filters loopback
                 */

-               if (tp->t_state == TCP_NSTATES)
-                       continue;      
+               if (tp->t_state == TCP_NSTATES) {
+                       tcp_unlock(so, 1, 0);
+                       continue; 
+               }
+

 
                for (i = 0; i < TCPT_NTIMERS; i++) {
                        if (tp->t_timer[i] && --tp->t_timer[i] == 0) {
 
                for (i = 0; i < TCPT_NTIMERS; i++) {
                        if (tp->t_timer[i] && --tp->t_timer[i] == 0) {


@@ -288,9 +321,9 @@ tcp_slowtimo()
                tp->t_rcvtime++;
                tp->t_starttime++;
                if (tp->t_rtttime)
                tp->t_rcvtime++;
                tp->t_starttime++;
                if (tp->t_rtttime)

-                       tp->t_rtttime++;
+                       tp->t_rtttime++;        

 tpgone:
 tpgone:

-               ;
+               tcp_unlock(so, 1, 0);

        }
 
 #if KDEBUG
        }
 
 #if KDEBUG


@@ -302,13 +335,28 @@ tpgone:
         * Process the items in the current time-wait slot
         */
 
         * Process the items in the current time-wait slot
         */
 

-       for (ip = time_wait_slots[cur_tw_slot].lh_first; ip; ip = ipnxt)
+       for (inp = time_wait_slots[cur_tw_slot].lh_first; inp; inp = inpnxt)

        {
        {

+               inpnxt = inp->inp_list.le_next;

 #if KDEBUG
                tws_checked++;
 #endif
 #if KDEBUG
                tws_checked++;
 #endif

-               ipnxt = ip->inp_list.le_next;
-               tp = intotcpcb(ip);
+
+               if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) 
+                       continue;
+
+               tcp_lock(inp->inp_socket, 1, 0);
+
+               if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) 
+                       goto twunlock;
+
+               tp = intotcpcb(inp);
+               if (tp == NULL) { /* tp already closed, remove from list */
+#if TEMPDEBUG
+                       printf("tcp_slowtimo: tp is null in time-wait slot!\n");
+#endif
+                       goto twunlock;
+               }

                if (tp->t_timer[TCPT_2MSL] >= N_TIME_WAIT_SLOTS) {
                    tp->t_timer[TCPT_2MSL] -= N_TIME_WAIT_SLOTS;
                    tp->t_rcvtime += N_TIME_WAIT_SLOTS;
                if (tp->t_timer[TCPT_2MSL] >= N_TIME_WAIT_SLOTS) {
                    tp->t_timer[TCPT_2MSL] -= N_TIME_WAIT_SLOTS;
                    tp->t_rcvtime += N_TIME_WAIT_SLOTS;


@@ -316,14 +364,77 @@ tpgone:
                else
                    tp->t_timer[TCPT_2MSL] = 0;
 
                else
                    tp->t_timer[TCPT_2MSL] = 0;
 

-               if (tp->t_timer[TCPT_2MSL] == 0) 
-                   tp = tcp_timers(tp, TCPT_2MSL);
+               if (tp->t_timer[TCPT_2MSL] == 0)  
+                   tp = tcp_timers(tp, TCPT_2MSL);     /* tp can be returned null if tcp_close is called */
+twunlock:
+               tcp_unlock(inp->inp_socket, 1, 0);
+       }
+
+       if (lck_rw_lock_shared_to_exclusive(pcbinfo->mtx) != 0)
+               lck_rw_lock_exclusive(pcbinfo->mtx);    /* Upgrade failed, lost lock no take it again exclusive */
+
+
+       for (inp = tcb.lh_first; inp != NULL; inp = inpnxt) {
+               inpnxt = inp->inp_list.le_next;
+               /* Ignore nat/SharedIP dummy pcbs */
+               if (inp->inp_socket == &tcbinfo.nat_dummy_socket)
+                               continue;
+
+               if (inp->inp_wantcnt != WNT_STOPUSING) 
+                       continue;
+
+               so = inp->inp_socket;
+               if (!lck_mtx_try_lock(inp->inpcb_mtx)) {/* skip if in use */
+#if TEMPDEBUG
+                       printf("tcp_slowtimo so=%x STOPUSING but locked...\n", so);
+#endif
+                       continue;
+               }
+
+               if (so->so_usecount == 0) 
+                       in_pcbdispose(inp);
+               else {
+                       tp = intotcpcb(inp);
+                       /* Check for embryonic socket stuck on listener queue (4023660) */
+                       if ((so->so_usecount == 1) && (tp->t_state == TCPS_CLOSED) &&
+                           (so->so_head != NULL) && (so->so_state & SS_INCOMP)) {
+                               so->so_usecount--; 
+                               in_pcbdispose(inp);
+                       } else
+                               lck_mtx_unlock(inp->inpcb_mtx);
+               }

        }
 
        }
 

+       /* Now cleanup the time wait ones */
+       for (inp = time_wait_slots[cur_tw_slot].lh_first; inp; inp = inpnxt)
+       {
+               inpnxt = inp->inp_list.le_next;
+
+               if (inp->inp_wantcnt != WNT_STOPUSING) 
+                       continue;
+
+               so = inp->inp_socket;
+               if (!lck_mtx_try_lock(inp->inpcb_mtx)) /* skip if in use */
+                       continue;
+               if (so->so_usecount == 0)  
+                       in_pcbdispose(inp);
+               else  {
+                       tp = intotcpcb(inp);
+                       /* Check for embryonic socket stuck on listener queue (4023660) */
+                       if ((so->so_usecount == 1) && (tp->t_state == TCPS_CLOSED) &&
+                           (so->so_head != NULL) && (so->so_state & SS_INCOMP)) {
+                               so->so_usecount--; 
+                               in_pcbdispose(inp);
+                       } else
+                               lck_mtx_unlock(inp->inpcb_mtx);
+               }
+       }
+
+       tcp_now++;

        if (++cur_tw_slot >= N_TIME_WAIT_SLOTS)
                cur_tw_slot = 0;
        if (++cur_tw_slot >= N_TIME_WAIT_SLOTS)
                cur_tw_slot = 0;

-       tcp_now++;                                      /* for timestamps */
-       splx(s);
+       
+       lck_rw_done(pcbinfo->mtx);

        KERNEL_DEBUG(DBG_FNC_TCP_SLOW | DBG_FUNC_END, tws_checked, cur_tw_slot,0,0,0);
 }
 
        KERNEL_DEBUG(DBG_FNC_TCP_SLOW | DBG_FUNC_END, tws_checked, cur_tw_slot,0,0,0);
 }
 


@@ -360,10 +471,15 @@ tcp_timers(tp, timer)
        struct socket *so_tmp;
        struct tcptemp *t_template;
 
        struct socket *so_tmp;
        struct tcptemp *t_template;
 

+#if TCPDEBUG
+       int ostate;
+#endif
+

 #if INET6
        int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV4) == 0;
 #endif /* INET6 */
 
 #if INET6
        int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV4) == 0;
 #endif /* INET6 */
 

+       so_tmp = tp->t_inpcb->inp_socket;

 
        switch (timer) {
 
 
        switch (timer) {
 


@@ -376,11 +492,13 @@ tcp_timers(tp, timer)
        case TCPT_2MSL:
                if (tp->t_state != TCPS_TIME_WAIT &&
                    tp->t_rcvtime <= tcp_maxidle) {
        case TCPT_2MSL:
                if (tp->t_state != TCPS_TIME_WAIT &&
                    tp->t_rcvtime <= tcp_maxidle) {

-                       tp->t_timer[TCPT_2MSL] = tcp_keepintvl;
-                       add_to_time_wait(tp);
+                       tp->t_timer[TCPT_2MSL] = (unsigned long)tcp_keepintvl;
+                       add_to_time_wait_locked(tp);

                }
                }

-               else
+               else {

                        tp = tcp_close(tp);
                        tp = tcp_close(tp);

+                       return(tp);
+               }

                break;
 
        /*
                break;
 
        /*


@@ -392,7 +510,6 @@ tcp_timers(tp, timer)
                if (++tp->t_rxtshift > TCP_MAXRXTSHIFT) {
                        tp->t_rxtshift = TCP_MAXRXTSHIFT;
                        tcpstat.tcps_timeoutdrop++;
                if (++tp->t_rxtshift > TCP_MAXRXTSHIFT) {
                        tp->t_rxtshift = TCP_MAXRXTSHIFT;
                        tcpstat.tcps_timeoutdrop++;

-                       so_tmp = tp->t_inpcb->inp_socket;

                        tp = tcp_drop(tp, tp->t_softerror ?
                            tp->t_softerror : ETIMEDOUT);
                        postevent(so_tmp, 0, EV_TIMEOUT);                       
                        tp = tcp_drop(tp, tp->t_softerror ?
                            tp->t_softerror : ETIMEDOUT);
                        postevent(so_tmp, 0, EV_TIMEOUT);                       


@@ -537,7 +654,7 @@ tcp_timers(tp, timer)
                if ((always_keepalive ||
                    tp->t_inpcb->inp_socket->so_options & SO_KEEPALIVE) &&
                    tp->t_state <= TCPS_CLOSING) {
                if ((always_keepalive ||
                    tp->t_inpcb->inp_socket->so_options & SO_KEEPALIVE) &&
                    tp->t_state <= TCPS_CLOSING) {

-                       if (tp->t_rcvtime >= tcp_keepidle + tcp_maxidle)
+                       if (tp->t_rcvtime >= TCP_KEEPIDLE(tp) + (unsigned long)tcp_maxidle)

                                goto dropit;
                        /*
                         * Send a packet designed to force a response
                                goto dropit;
                        /*
                         * Send a packet designed to force a response


@@ -561,7 +678,7 @@ tcp_timers(tp, timer)
                        }
                        tp->t_timer[TCPT_KEEP] = tcp_keepintvl;
                } else
                        }
                        tp->t_timer[TCPT_KEEP] = tcp_keepintvl;
                } else

-                       tp->t_timer[TCPT_KEEP] = tcp_keepidle;
+                       tp->t_timer[TCPT_KEEP] = TCP_KEEPIDLE(tp);

                break;
 
 #if TCPDEBUG
                break;
 
 #if TCPDEBUG


@@ -571,7 +688,6 @@ tcp_timers(tp, timer)
 #endif
        dropit:
                tcpstat.tcps_keepdrops++;
 #endif
        dropit:
                tcpstat.tcps_keepdrops++;

-               so_tmp = tp->t_inpcb->inp_socket;

                tp = tcp_drop(tp, ETIMEDOUT);
                postevent(so_tmp, 0, EV_TIMEOUT);
                break;
                tp = tcp_drop(tp, ETIMEDOUT);
                postevent(so_tmp, 0, EV_TIMEOUT);
                break;