bsd/netinet/ip_fw.h

   1 /*
   2  * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Copyright (c) 1993 Daniel Boulet
  30  * Copyright (c) 1994 Ugen J.S.Antsilevich
  31  *
  32  * Redistribution and use in source forms, with and without modification,
  33  * are permitted provided that this entire comment appears intact.
  34  *
  35  * Redistribution in binary form may occur without any restrictions.
  36  * Obviously, it would be nice if you gave credit where credit is due
  37  * but requiring it would be too onerous.
  38  *
  39  * This software is provided ``AS IS'' without any warranties of any kind.
  40  *
  41  */
  42
  43 #ifndef _IP_FW_H
  44 #define _IP_FW_H
  45 #include <sys/appleapiopts.h>
  46
  47 #ifdef IPFW2
  48 #include <netinet/ip_fw2.h>
  49 #else /* !IPFW2, good old ipfw */
  50
  51 #include <sys/queue.h>
  52
  53
  54 #define IP_FW_CURRENT_API_VERSION 20    /* Version of this API */
  55
  56
  57 /*
  58  * This union structure identifies an interface, either explicitly
  59  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
  60  * and IP_FW_F_OIFNAME say how to interpret this structure. An
  61  * interface unit number of -1 matches any unit number, while an
  62  * IP address of 0.0.0.0 indicates matches any interface.
  63  *
  64  * The receive and transmit interfaces are only compared against the
  65  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
  66  * is set. Note some packets lack a receive or transmit interface
  67  * (in which case the missing "interface" never matches).
  68  */
  69
  70 union ip_fw_if {
  71     struct in_addr fu_via_ip;   /* Specified by IP address */
  72     struct {                    /* Specified by interface name */
  73 #define FW_IFNLEN     10 /* need room ! was IFNAMSIZ */
  74             char  name[FW_IFNLEN];
  75             short unit;         /* -1 means match any unit */
  76     } fu_via_if;
  77 };
  78
  79 /*
  80  * Format of an IP firewall descriptor
  81  *
  82  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
  83  * fw_flg and fw_n*p are stored in host byte order (of course).
  84  * Port numbers are stored in HOST byte order.
  85  */
  86
  87 struct ip_fw {
  88         u_int32_t version;              /* Version of this structure.  Should always be */
  89                                                         /* set to IP_FW_CURRENT_API_VERSION by clients. */
  90         void *context;                  /* Context that is usable by user processes to */
  91                                                         /* identify this rule. */
  92     u_int64_t fw_pcnt,fw_bcnt;          /* Packet and byte counters */
  93     struct in_addr fw_src, fw_dst;      /* Source and destination IP addr */
  94     struct in_addr fw_smsk, fw_dmsk;    /* Mask for src and dest IP addr */
  95     u_short fw_number;                  /* Rule number */
  96     u_int fw_flg;                       /* Flags word */
  97 #define IP_FW_MAX_PORTS 10              /* A reasonable maximum */
  98         union {
  99         u_short fw_pts[IP_FW_MAX_PORTS];        /* Array of port numbers to match */
 100 #define IP_FW_ICMPTYPES_MAX     128
 101 #define IP_FW_ICMPTYPES_DIM     (IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
 102         unsigned fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
 103         } fw_uar;
 104     u_int fw_ipflg;                     /* IP flags word */
 105     u_char fw_ipopt,fw_ipnopt;          /* IP options set/unset */
 106     u_char fw_tcpopt,fw_tcpnopt;        /* TCP options set/unset */
 107     u_char fw_tcpf,fw_tcpnf;            /* TCP flags set/unset */
 108     long timestamp;                     /* timestamp (tv_sec) of last match */
 109     union ip_fw_if fw_in_if, fw_out_if; /* Incoming and outgoing interfaces */
 110     union {
 111         u_short fu_divert_port;         /* Divert/tee port (options IPDIVERT) */
 112         u_short fu_pipe_nr;             /* queue number (option DUMMYNET) */
 113         u_short fu_skipto_rule;         /* SKIPTO command rule number */
 114         u_short fu_reject_code;         /* REJECT response code */
 115         struct sockaddr_in fu_fwd_ip;
 116     } fw_un;
 117     u_char fw_prot;                     /* IP protocol */
 118         /*
 119          * N'of src ports and # of dst ports in ports array (dst ports
 120          * follow src ports; max of 10 ports in all; count of 0 means
 121          * match all ports)
 122          */
 123     u_char fw_nports;
 124     void *pipe_ptr;                    /* flow_set ptr for dummynet pipe */
 125     void *next_rule_ptr ;              /* next rule in case of match */
 126     uid_t fw_uid;                       /* uid to match */
 127     int fw_logamount;                   /* amount to log */
 128     u_int64_t fw_loghighest;            /* highest number packet to log */
 129 };
 130
 131 /*
 132  * extended ipfw structure... some fields in the original struct
 133  * can be used to pass parameters up/down, namely pointers
 134  *     void *pipe_ptr
 135  *     void *next_rule_ptr
 136  * some others can be used to pass parameters down, namely counters etc.
 137  *     u_int64_t fw_pcnt,fw_bcnt;
 138  *     long timestamp;
 139  */
 140
 141 struct ip_fw_ext {             /* extended structure */
 142     struct ip_fw rule;      /* must be at offset 0 */
 143     long    dont_match_prob;        /* 0x7fffffff means 1.0, always fail */
 144     u_int   dyn_type;  /* type for dynamic rule */
 145 };
 146
 147 #define IP_FW_GETNSRCP(rule)            ((rule)->fw_nports & 0x0f)
 148 #define IP_FW_SETNSRCP(rule, n)         do {                            \
 149                                           (rule)->fw_nports &= ~0x0f;   \
 150                                           (rule)->fw_nports |= (n);     \
 151                                         } while (0)
 152 #define IP_FW_GETNDSTP(rule)            ((rule)->fw_nports >> 4)
 153 #define IP_FW_SETNDSTP(rule, n)         do {                            \
 154                                           (rule)->fw_nports &= ~0xf0;   \
 155                                           (rule)->fw_nports |= (n) << 4;\
 156                                         } while (0)
 157
 158 #define fw_divert_port  fw_un.fu_divert_port
 159 #define fw_skipto_rule  fw_un.fu_skipto_rule
 160 #define fw_reject_code  fw_un.fu_reject_code
 161 #define fw_pipe_nr      fw_un.fu_pipe_nr
 162 #define fw_fwd_ip       fw_un.fu_fwd_ip
 163
 164 struct ip_fw_chain {
 165         LIST_ENTRY(ip_fw_chain) next;
 166         struct ip_fw *rule;
 167 };
 168
 169 /*
 170  * Flow mask/flow id for each queue.
 171  */
 172 struct ipfw_flow_id {
 173     u_int32_t dst_ip, src_ip ;
 174     u_int16_t dst_port, src_port ;
 175     u_int8_t proto ;
 176     u_int8_t flags ;    /* protocol-specific flags */
 177 } ;
 178
 179 /*
 180  * dynamic ipfw rule
 181  */
 182 struct ipfw_dyn_rule {
 183     struct ipfw_dyn_rule *next ;
 184
 185     struct ipfw_flow_id id ;
 186     struct ipfw_flow_id mask ;
 187     struct ip_fw_chain *chain ;         /* pointer to parent rule       */
 188     u_int32_t type ;                    /* rule type                    */
 189     u_int32_t expire ;                  /* expire time                  */
 190     u_int64_t pcnt, bcnt;               /* match counters               */
 191     u_int32_t bucket ;                  /* which bucket in hash table   */
 192     u_int32_t state ;                   /* state of this rule (typ. a   */
 193                                         /* combination of TCP flags)    */
 194 } ;
 195
 196 /*
 197  * Values for "flags" field .
 198  */
 199 #define IP_FW_F_COMMAND 0x000000ff      /* Mask for type of chain entry:        */
 200 #define IP_FW_F_DENY    0x00000000      /* This is a deny rule                  */
 201 #define IP_FW_F_REJECT  0x00000001      /* Deny and send a response packet      */
 202 #define IP_FW_F_ACCEPT  0x00000002      /* This is an accept rule               */
 203 #define IP_FW_F_COUNT   0x00000003      /* This is a count rule                 */
 204 #define IP_FW_F_DIVERT  0x00000004      /* This is a divert rule                */
 205 #define IP_FW_F_TEE     0x00000005      /* This is a tee rule                   */
 206 #define IP_FW_F_SKIPTO  0x00000006      /* This is a skipto rule                */
 207 #define IP_FW_F_FWD     0x00000007      /* This is a "change forwarding address" rule */
 208 #define IP_FW_F_PIPE    0x00000008      /* This is a dummynet rule */
 209 #define IP_FW_F_QUEUE   0x00000009      /* This is a dummynet queue */
 210
 211 #define IP_FW_F_IN      0x00000100      /* Check inbound packets                */
 212 #define IP_FW_F_OUT     0x00000200      /* Check outbound packets               */
 213 #define IP_FW_F_IIFACE  0x00000400      /* Apply inbound interface test         */
 214 #define IP_FW_F_OIFACE  0x00000800      /* Apply outbound interface test        */
 215
 216 #define IP_FW_F_PRN     0x00001000      /* Print if this rule matches           */
 217
 218 #define IP_FW_F_SRNG    0x00002000      /* The first two src ports are a min    *
 219                                          * and max range (stored in host byte   *
 220                                          * order).                              */
 221
 222 #define IP_FW_F_DRNG    0x00004000      /* The first two dst ports are a min    *
 223                                          * and max range (stored in host byte   *
 224                                          * order).                              */
 225
 226 #define IP_FW_F_FRAG    0x00008000      /* Fragment                             */
 227
 228 #define IP_FW_F_IIFNAME 0x00010000      /* In interface by name/unit (not IP)   */
 229 #define IP_FW_F_OIFNAME 0x00020000      /* Out interface by name/unit (not IP)  */
 230
 231 #define IP_FW_F_INVSRC  0x00040000      /* Invert sense of src check            */
 232 #define IP_FW_F_INVDST  0x00080000      /* Invert sense of dst check            */
 233
 234 #define IP_FW_F_ICMPBIT 0x00100000      /* ICMP type bitmap is valid            */
 235
 236 #define IP_FW_F_UID     0x00200000      /* filter by uid                        */
 237
 238 #define IP_FW_F_RND_MATCH 0x00800000    /* probabilistic rule match             */
 239 #define IP_FW_F_SMSK    0x01000000      /* src-port + mask                      */
 240 #define IP_FW_F_DMSK    0x02000000      /* dst-port + mask                      */
 241 #define IP_FW_BRIDGED   0x04000000      /* only match bridged packets           */
 242 #define IP_FW_F_KEEP_S  0x08000000      /* keep state                           */
 243 #define IP_FW_F_CHECK_S 0x10000000      /* check state                          */
 244
 245 #define IP_FW_F_SME     0x20000000      /* source = me                          */
 246 #define IP_FW_F_DME     0x40000000      /* destination = me                     */
 247
 248 #define IP_FW_F_MASK    0x7FFFFFFF      /* All possible flag bits mask          */
 249
 250 /*
 251  * Flags for the 'fw_ipflg' field, for comparing values of ip and its protocols.
 252  */
 253 #define IP_FW_IF_TCPEST 0x00000020      /* established TCP connection */
 254 #define IP_FW_IF_TCPMSK 0x00000020      /* mask of all TCP values */
 255
 256 /*
 257  * For backwards compatibility with rules specifying "via iface" but
 258  * not restricted to only "in" or "out" packets, we define this combination
 259  * of bits to represent this configuration.
 260  */
 261
 262 #define IF_FW_F_VIAHACK (IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
 263
 264 /*
 265  * Definitions for REJECT response codes.
 266  * Values less than 256 correspond to ICMP unreachable codes.
 267  */
 268 #define IP_FW_REJECT_RST        0x0100          /* TCP packets: send RST */
 269
 270 /*
 271  * Definitions for IP option names.
 272  */
 273 #define IP_FW_IPOPT_LSRR        0x01
 274 #define IP_FW_IPOPT_SSRR        0x02
 275 #define IP_FW_IPOPT_RR          0x04
 276 #define IP_FW_IPOPT_TS          0x08
 277
 278 /*
 279  * Definitions for TCP option names.
 280  */
 281 #define IP_FW_TCPOPT_MSS        0x01
 282 #define IP_FW_TCPOPT_WINDOW     0x02
 283 #define IP_FW_TCPOPT_SACK       0x04
 284 #define IP_FW_TCPOPT_TS         0x08
 285 #define IP_FW_TCPOPT_CC         0x10
 286
 287 /*
 288  * Definitions for TCP flags.
 289  */
 290 #define IP_FW_TCPF_FIN          TH_FIN
 291 #define IP_FW_TCPF_SYN          TH_SYN
 292 #define IP_FW_TCPF_RST          TH_RST
 293 #define IP_FW_TCPF_PSH          TH_PUSH
 294 #define IP_FW_TCPF_ACK          TH_ACK
 295 #define IP_FW_TCPF_URG          TH_URG
 296
 297 /*
 298  * Main firewall chains definitions and global var's definitions.
 299  */
 300 #ifdef KERNEL_PRIVATE
 301
 302 #define IP_FW_PORT_DYNT_FLAG    0x10000
 303 #define IP_FW_PORT_TEE_FLAG     0x20000
 304 #define IP_FW_PORT_DENY_FLAG    0x40000
 305
 306 /*
 307  * Function definitions.
 308  */
 309 void ip_fw_init(void);
 310
 311 /* Firewall hooks */
 312 struct ip;
 313 struct sockopt;
 314 typedef int ip_fw_chk_t(struct ip **, int, struct ifnet *, u_int16_t *,
 315              struct mbuf **, struct ip_fw_chain **, struct sockaddr_in **);
 316 typedef int ip_fw_ctl_t(struct sockopt *);
 317 extern  ip_fw_chk_t *ip_fw_chk_ptr;
 318 extern  ip_fw_ctl_t *ip_fw_ctl_ptr;
 319 extern int fw_one_pass;
 320 extern int fw_enable;
 321 extern struct ipfw_flow_id last_pkt ;
 322 #endif KERNEL_PRIVATE
 323
 324 #endif !IPFW2
 325 #endif _IP_FW_H