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
  46 #if !__LP64__
  47
  48 #include <sys/appleapiopts.h>
  49
  50 #ifdef IPFW2
  51 #include <netinet/ip_fw2.h>
  52 #else /* !IPFW2, good old ipfw */
  53
  54 #include <sys/queue.h>
  55 #include <sys/types.h>          /* u_ types */
  56
  57 #define IP_FW_CURRENT_API_VERSION 20    /* Version of this API */
  58
  59
  60 /*
  61  * This union structure identifies an interface, either explicitly
  62  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
  63  * and IP_FW_F_OIFNAME say how to interpret this structure. An
  64  * interface unit number of -1 matches any unit number, while an
  65  * IP address of 0.0.0.0 indicates matches any interface.
  66  *
  67  * The receive and transmit interfaces are only compared against the
  68  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
  69  * is set. Note some packets lack a receive or transmit interface
  70  * (in which case the missing "interface" never matches).
  71  */
  72
  73 union ip_fw_if {
  74     struct in_addr fu_via_ip;   /* Specified by IP address */
  75     struct {                    /* Specified by interface name */
  76 #define FW_IFNLEN     10 /* need room ! was IFNAMSIZ */
  77             char  name[FW_IFNLEN];
  78             short unit;         /* -1 means match any unit */
  79     } fu_via_if;
  80 };
  81
  82 /*
  83  * Format of an IP firewall descriptor
  84  *
  85  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
  86  * fw_flg and fw_n*p are stored in host byte order (of course).
  87  * Port numbers are stored in HOST byte order.
  88  */
  89
  90 struct ip_fw {
  91         u_int32_t version;              /* Version of this structure.  Should always be */
  92                                                         /* set to IP_FW_CURRENT_API_VERSION by clients. */
  93         void *context;                  /* Context that is usable by user processes to */
  94                                                         /* identify this rule. */
  95     u_int64_t fw_pcnt,fw_bcnt;          /* Packet and byte counters */
  96     struct in_addr fw_src, fw_dst;      /* Source and destination IP addr */
  97     struct in_addr fw_smsk, fw_dmsk;    /* Mask for src and dest IP addr */
  98     u_short fw_number;                  /* Rule number */
  99     u_int fw_flg;                       /* Flags word */
 100 #define IP_FW_MAX_PORTS 10              /* A reasonable maximum */
 101         union {
 102         u_short fw_pts[IP_FW_MAX_PORTS];        /* Array of port numbers to match */
 103 #define IP_FW_ICMPTYPES_MAX     128
 104 #define IP_FW_ICMPTYPES_DIM     (IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
 105         unsigned fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
 106         } fw_uar;
 107     u_int fw_ipflg;                     /* IP flags word */
 108     u_char fw_ipopt,fw_ipnopt;          /* IP options set/unset */
 109     u_char fw_tcpopt,fw_tcpnopt;        /* TCP options set/unset */
 110     u_char fw_tcpf,fw_tcpnf;            /* TCP flags set/unset */
 111     long timestamp;                     /* timestamp (tv_sec) of last match */
 112     union ip_fw_if fw_in_if, fw_out_if; /* Incoming and outgoing interfaces */
 113     union {
 114         u_short fu_divert_port;         /* Divert/tee port (options IPDIVERT) */
 115         u_short fu_pipe_nr;             /* queue number (option DUMMYNET) */
 116         u_short fu_skipto_rule;         /* SKIPTO command rule number */
 117         u_short fu_reject_code;         /* REJECT response code */
 118         struct sockaddr_in fu_fwd_ip;
 119     } fw_un;
 120     u_char fw_prot;                     /* IP protocol */
 121         /*
 122          * N'of src ports and # of dst ports in ports array (dst ports
 123          * follow src ports; max of 10 ports in all; count of 0 means
 124          * match all ports)
 125          */
 126     u_char fw_nports;
 127     void *pipe_ptr;                    /* flow_set ptr for dummynet pipe */
 128     void *next_rule_ptr ;              /* next rule in case of match */
 129     uid_t fw_uid;                       /* uid to match */
 130     int fw_logamount;                   /* amount to log */
 131     u_int64_t fw_loghighest;            /* highest number packet to log */
 132 };
 133
 134 /*
 135  * extended ipfw structure... some fields in the original struct
 136  * can be used to pass parameters up/down, namely pointers
 137  *     void *pipe_ptr
 138  *     void *next_rule_ptr
 139  * some others can be used to pass parameters down, namely counters etc.
 140  *     u_int64_t fw_pcnt,fw_bcnt;
 141  *     long timestamp;
 142  */
 143
 144 struct ip_fw_ext {             /* extended structure */
 145     struct ip_fw rule;      /* must be at offset 0 */
 146     long    dont_match_prob;        /* 0x7fffffff means 1.0, always fail */
 147     u_int   dyn_type;  /* type for dynamic rule */
 148 };
 149
 150 #define IP_FW_GETNSRCP(rule)            ((rule)->fw_nports & 0x0f)
 151 #define IP_FW_SETNSRCP(rule, n)         do {                            \
 152                                           (rule)->fw_nports &= ~0x0f;   \
 153                                           (rule)->fw_nports |= (n);     \
 154                                         } while (0)
 155 #define IP_FW_GETNDSTP(rule)            ((rule)->fw_nports >> 4)
 156 #define IP_FW_SETNDSTP(rule, n)         do {                            \
 157                                           (rule)->fw_nports &= ~0xf0;   \
 158                                           (rule)->fw_nports |= (n) << 4;\
 159                                         } while (0)
 160
 161 #define fw_divert_port  fw_un.fu_divert_port
 162 #define fw_skipto_rule  fw_un.fu_skipto_rule
 163 #define fw_reject_code  fw_un.fu_reject_code
 164 #define fw_pipe_nr      fw_un.fu_pipe_nr
 165 #define fw_fwd_ip       fw_un.fu_fwd_ip
 166
 167 struct ip_fw_chain {
 168         LIST_ENTRY(ip_fw_chain) next;
 169         struct ip_fw *rule;
 170 };
 171
 172 /*
 173  * Flow mask/flow id for each queue.
 174  */
 175 struct ipfw_flow_id {
 176     u_int32_t dst_ip, src_ip ;
 177     u_int16_t dst_port, src_port ;
 178     u_int8_t proto ;
 179     u_int8_t flags ;    /* protocol-specific flags */
 180 } ;
 181
 182 /*
 183  * dynamic ipfw rule
 184  */
 185 struct ipfw_dyn_rule {
 186     struct ipfw_dyn_rule *next ;
 187
 188     struct ipfw_flow_id id ;
 189     struct ipfw_flow_id mask ;
 190     struct ip_fw_chain *chain ;         /* pointer to parent rule       */
 191     u_int32_t type ;                    /* rule type                    */
 192     u_int32_t expire ;                  /* expire time                  */
 193     u_int64_t pcnt, bcnt;               /* match counters               */
 194     u_int32_t bucket ;                  /* which bucket in hash table   */
 195     u_int32_t state ;                   /* state of this rule (typ. a   */
 196                                         /* combination of TCP flags)    */
 197 } ;
 198
 199 /*
 200  * Values for "flags" field .
 201  */
 202 #define IP_FW_F_COMMAND 0x000000ff      /* Mask for type of chain entry:        */
 203 #define IP_FW_F_DENY    0x00000000      /* This is a deny rule                  */
 204 #define IP_FW_F_REJECT  0x00000001      /* Deny and send a response packet      */
 205 #define IP_FW_F_ACCEPT  0x00000002      /* This is an accept rule               */
 206 #define IP_FW_F_COUNT   0x00000003      /* This is a count rule                 */
 207 #define IP_FW_F_DIVERT  0x00000004      /* This is a divert rule                */
 208 #define IP_FW_F_TEE     0x00000005      /* This is a tee rule                   */
 209 #define IP_FW_F_SKIPTO  0x00000006      /* This is a skipto rule                */
 210 #define IP_FW_F_FWD     0x00000007      /* This is a "change forwarding address" rule */
 211 #define IP_FW_F_PIPE    0x00000008      /* This is a dummynet rule */
 212 #define IP_FW_F_QUEUE   0x00000009      /* This is a dummynet queue */
 213
 214 #define IP_FW_F_IN      0x00000100      /* Check inbound packets                */
 215 #define IP_FW_F_OUT     0x00000200      /* Check outbound packets               */
 216 #define IP_FW_F_IIFACE  0x00000400      /* Apply inbound interface test         */
 217 #define IP_FW_F_OIFACE  0x00000800      /* Apply outbound interface test        */
 218
 219 #define IP_FW_F_PRN     0x00001000      /* Print if this rule matches           */
 220
 221 #define IP_FW_F_SRNG    0x00002000      /* The first two src ports are a min    *
 222                                          * and max range (stored in host byte   *
 223                                          * order).                              */
 224
 225 #define IP_FW_F_DRNG    0x00004000      /* The first two dst ports are a min    *
 226                                          * and max range (stored in host byte   *
 227                                          * order).                              */
 228
 229 #define IP_FW_F_FRAG    0x00008000      /* Fragment                             */
 230
 231 #define IP_FW_F_IIFNAME 0x00010000      /* In interface by name/unit (not IP)   */
 232 #define IP_FW_F_OIFNAME 0x00020000      /* Out interface by name/unit (not IP)  */
 233
 234 #define IP_FW_F_INVSRC  0x00040000      /* Invert sense of src check            */
 235 #define IP_FW_F_INVDST  0x00080000      /* Invert sense of dst check            */
 236
 237 #define IP_FW_F_ICMPBIT 0x00100000      /* ICMP type bitmap is valid            */
 238
 239 #define IP_FW_F_UID     0x00200000      /* filter by uid                        */
 240
 241 #define IP_FW_F_RND_MATCH 0x00800000    /* probabilistic rule match             */
 242 #define IP_FW_F_SMSK    0x01000000      /* src-port + mask                      */
 243 #define IP_FW_F_DMSK    0x02000000      /* dst-port + mask                      */
 244 #define IP_FW_BRIDGED   0x04000000      /* only match bridged packets           */
 245 #define IP_FW_F_KEEP_S  0x08000000      /* keep state                           */
 246 #define IP_FW_F_CHECK_S 0x10000000      /* check state                          */
 247
 248 #define IP_FW_F_SME     0x20000000      /* source = me                          */
 249 #define IP_FW_F_DME     0x40000000      /* destination = me                     */
 250
 251 #define IP_FW_F_MASK    0x7FFFFFFF      /* All possible flag bits mask          */
 252
 253 /*
 254  * Flags for the 'fw_ipflg' field, for comparing values of ip and its protocols.
 255  */
 256 #define IP_FW_IF_TCPEST 0x00000020      /* established TCP connection */
 257 #define IP_FW_IF_TCPMSK 0x00000020      /* mask of all TCP values */
 258
 259 /*
 260  * For backwards compatibility with rules specifying "via iface" but
 261  * not restricted to only "in" or "out" packets, we define this combination
 262  * of bits to represent this configuration.
 263  */
 264
 265 #define IF_FW_F_VIAHACK (IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
 266
 267 /*
 268  * Definitions for REJECT response codes.
 269  * Values less than 256 correspond to ICMP unreachable codes.
 270  */
 271 #define IP_FW_REJECT_RST        0x0100          /* TCP packets: send RST */
 272
 273 /*
 274  * Definitions for IP option names.
 275  */
 276 #define IP_FW_IPOPT_LSRR        0x01
 277 #define IP_FW_IPOPT_SSRR        0x02
 278 #define IP_FW_IPOPT_RR          0x04
 279 #define IP_FW_IPOPT_TS          0x08
 280
 281 /*
 282  * Definitions for TCP option names.
 283  */
 284 #define IP_FW_TCPOPT_MSS        0x01
 285 #define IP_FW_TCPOPT_WINDOW     0x02
 286 #define IP_FW_TCPOPT_SACK       0x04
 287 #define IP_FW_TCPOPT_TS         0x08
 288 #define IP_FW_TCPOPT_CC         0x10
 289
 290 /*
 291  * Definitions for TCP flags.
 292  */
 293 #define IP_FW_TCPF_FIN          TH_FIN
 294 #define IP_FW_TCPF_SYN          TH_SYN
 295 #define IP_FW_TCPF_RST          TH_RST
 296 #define IP_FW_TCPF_PSH          TH_PUSH
 297 #define IP_FW_TCPF_ACK          TH_ACK
 298 #define IP_FW_TCPF_URG          TH_URG
 299
 300 /*
 301  * Main firewall chains definitions and global var's definitions.
 302  */
 303 #ifdef KERNEL_PRIVATE
 304
 305 #define IP_FW_PORT_DYNT_FLAG    0x10000
 306 #define IP_FW_PORT_TEE_FLAG     0x20000
 307 #define IP_FW_PORT_DENY_FLAG    0x40000
 308
 309 /*
 310  * Function definitions.
 311  */
 312 void ip_fw_init(void);
 313
 314 /* Firewall hooks */
 315 struct ip;
 316 struct sockopt;
 317 typedef int ip_fw_chk_t(struct ip **, int, struct ifnet *, u_int16_t *,
 318              struct mbuf **, struct ip_fw_chain **, struct sockaddr_in **);
 319 typedef int ip_fw_ctl_t(struct sockopt *);
 320 extern  ip_fw_chk_t *ip_fw_chk_ptr;
 321 extern  ip_fw_ctl_t *ip_fw_ctl_ptr;
 322 extern int fw_one_pass;
 323 extern int fw_enable;
 324 #define IPFW_LOADED     (ip_fw_chk_ptr != NULL)
 325 extern struct ipfw_flow_id last_pkt ;
 326 #endif KERNEL_PRIVATE
 327
 328 #endif /* !__LP64__ */
 329 #endif !IPFW2
 330 #endif /* _IP_FW_H */