bsd/netinet/ip_fw.h

   1 /*
   2  * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1993 Daniel Boulet
  27  * Copyright (c) 1994 Ugen J.S.Antsilevich
  28  *
  29  * Redistribution and use in source forms, with and without modification,
  30  * are permitted provided that this entire comment appears intact.
  31  *
  32  * Redistribution in binary form may occur without any restrictions.
  33  * Obviously, it would be nice if you gave credit where credit is due
  34  * but requiring it would be too onerous.
  35  *
  36  * This software is provided ``AS IS'' without any warranties of any kind.
  37  *
  38  */
  39
  40 #ifndef _IP_FW_H
  41 #define _IP_FW_H
  42 #include <sys/appleapiopts.h>
  43
  44 #include <sys/queue.h>
  45
  46
  47 #define IP_FW_CURRENT_API_VERSION 20    /* Version of this API */
  48
  49
  50 /*
  51  * This union structure identifies an interface, either explicitly
  52  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
  53  * and IP_FW_F_OIFNAME say how to interpret this structure. An
  54  * interface unit number of -1 matches any unit number, while an
  55  * IP address of 0.0.0.0 indicates matches any interface.
  56  *
  57  * The receive and transmit interfaces are only compared against the
  58  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
  59  * is set. Note some packets lack a receive or transmit interface
  60  * (in which case the missing "interface" never matches).
  61  */
  62
  63 union ip_fw_if {
  64     struct in_addr fu_via_ip;   /* Specified by IP address */
  65     struct {                    /* Specified by interface name */
  66 #define FW_IFNLEN     10 /* need room ! was IFNAMSIZ */
  67             char  name[FW_IFNLEN];
  68             short unit;         /* -1 means match any unit */
  69     } fu_via_if;
  70 };
  71
  72 /*
  73  * Format of an IP firewall descriptor
  74  *
  75  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
  76  * fw_flg and fw_n*p are stored in host byte order (of course).
  77  * Port numbers are stored in HOST byte order.
  78  */
  79
  80 struct ip_fw {
  81         u_int32_t version;              /* Version of this structure.  Should always be */
  82                                                         /* set to IP_FW_CURRENT_API_VERSION by clients. */
  83         void *context;                  /* Context that is usable by user processes to */
  84                                                         /* identify this rule. */
  85     u_int64_t fw_pcnt,fw_bcnt;          /* Packet and byte counters */
  86     struct in_addr fw_src, fw_dst;      /* Source and destination IP addr */
  87     struct in_addr fw_smsk, fw_dmsk;    /* Mask for src and dest IP addr */
  88     u_short fw_number;                  /* Rule number */
  89     u_int fw_flg;                       /* Flags word */
  90 #define IP_FW_MAX_PORTS 10              /* A reasonable maximum */
  91         union {
  92         u_short fw_pts[IP_FW_MAX_PORTS];        /* Array of port numbers to match */
  93 #define IP_FW_ICMPTYPES_MAX     128
  94 #define IP_FW_ICMPTYPES_DIM     (IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
  95         unsigned fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
  96         } fw_uar;
  97     u_int fw_ipflg;                     /* IP flags word */
  98     u_char fw_ipopt,fw_ipnopt;          /* IP options set/unset */
  99     u_char fw_tcpopt,fw_tcpnopt;        /* TCP options set/unset */
 100     u_char fw_tcpf,fw_tcpnf;            /* TCP flags set/unset */
 101     long timestamp;                     /* timestamp (tv_sec) of last match */
 102     union ip_fw_if fw_in_if, fw_out_if; /* Incoming and outgoing interfaces */
 103     union {
 104         u_short fu_divert_port;         /* Divert/tee port (options IPDIVERT) */
 105         u_short fu_pipe_nr;             /* queue number (option DUMMYNET) */
 106         u_short fu_skipto_rule;         /* SKIPTO command rule number */
 107         u_short fu_reject_code;         /* REJECT response code */
 108         struct sockaddr_in fu_fwd_ip;
 109     } fw_un;
 110     u_char fw_prot;                     /* IP protocol */
 111         /*
 112          * N'of src ports and # of dst ports in ports array (dst ports
 113          * follow src ports; max of 10 ports in all; count of 0 means
 114          * match all ports)
 115          */
 116     u_char fw_nports;
 117     void *pipe_ptr;                    /* flow_set ptr for dummynet pipe */
 118     void *next_rule_ptr ;              /* next rule in case of match */
 119     uid_t fw_uid;                       /* uid to match */
 120     int fw_logamount;                   /* amount to log */
 121     u_int64_t fw_loghighest;            /* highest number packet to log */
 122 };
 123
 124 /*
 125  * extended ipfw structure... some fields in the original struct
 126  * can be used to pass parameters up/down, namely pointers
 127  *     void *pipe_ptr
 128  *     void *next_rule_ptr
 129  * some others can be used to pass parameters down, namely counters etc.
 130  *     u_int64_t fw_pcnt,fw_bcnt;
 131  *     long timestamp;
 132  */
 133
 134 struct ip_fw_ext {             /* extended structure */
 135     struct ip_fw rule;      /* must be at offset 0 */
 136     long    dont_match_prob;        /* 0x7fffffff means 1.0, always fail */
 137     u_int   dyn_type;  /* type for dynamic rule */
 138 };
 139
 140 #define IP_FW_GETNSRCP(rule)            ((rule)->fw_nports & 0x0f)
 141 #define IP_FW_SETNSRCP(rule, n)         do {                            \
 142                                           (rule)->fw_nports &= ~0x0f;   \
 143                                           (rule)->fw_nports |= (n);     \
 144                                         } while (0)
 145 #define IP_FW_GETNDSTP(rule)            ((rule)->fw_nports >> 4)
 146 #define IP_FW_SETNDSTP(rule, n)         do {                            \
 147                                           (rule)->fw_nports &= ~0xf0;   \
 148                                           (rule)->fw_nports |= (n) << 4;\
 149                                         } while (0)
 150
 151 #define fw_divert_port  fw_un.fu_divert_port
 152 #define fw_skipto_rule  fw_un.fu_skipto_rule
 153 #define fw_reject_code  fw_un.fu_reject_code
 154 #define fw_pipe_nr      fw_un.fu_pipe_nr
 155 #define fw_fwd_ip       fw_un.fu_fwd_ip
 156
 157 struct ip_fw_chain {
 158         LIST_ENTRY(ip_fw_chain) next;
 159         struct ip_fw *rule;
 160 };
 161
 162 /*
 163  * Flow mask/flow id for each queue.
 164  */
 165 struct ipfw_flow_id {
 166     u_int32_t dst_ip, src_ip ;
 167     u_int16_t dst_port, src_port ;
 168     u_int8_t proto ;
 169     u_int8_t flags ;    /* protocol-specific flags */
 170 } ;
 171
 172 /*
 173  * dynamic ipfw rule
 174  */
 175 struct ipfw_dyn_rule {
 176     struct ipfw_dyn_rule *next ;
 177
 178     struct ipfw_flow_id id ;
 179     struct ipfw_flow_id mask ;
 180     struct ip_fw_chain *chain ;         /* pointer to parent rule       */
 181     u_int32_t type ;                    /* rule type                    */
 182     u_int32_t expire ;                  /* expire time                  */
 183     u_int64_t pcnt, bcnt;               /* match counters               */
 184     u_int32_t bucket ;                  /* which bucket in hash table   */
 185     u_int32_t state ;                   /* state of this rule (typ. a   */
 186                                         /* combination of TCP flags)    */
 187 } ;
 188
 189 /*
 190  * Values for "flags" field .
 191  */
 192 #define IP_FW_F_COMMAND 0x000000ff      /* Mask for type of chain entry:        */
 193 #define IP_FW_F_DENY    0x00000000      /* This is a deny rule                  */
 194 #define IP_FW_F_REJECT  0x00000001      /* Deny and send a response packet      */
 195 #define IP_FW_F_ACCEPT  0x00000002      /* This is an accept rule               */
 196 #define IP_FW_F_COUNT   0x00000003      /* This is a count rule                 */
 197 #define IP_FW_F_DIVERT  0x00000004      /* This is a divert rule                */
 198 #define IP_FW_F_TEE     0x00000005      /* This is a tee rule                   */
 199 #define IP_FW_F_SKIPTO  0x00000006      /* This is a skipto rule                */
 200 #define IP_FW_F_FWD     0x00000007      /* This is a "change forwarding address" rule */
 201 #define IP_FW_F_PIPE    0x00000008      /* This is a dummynet rule */
 202 #define IP_FW_F_QUEUE   0x00000009      /* This is a dummynet queue */
 203
 204 #define IP_FW_F_IN      0x00000100      /* Check inbound packets                */
 205 #define IP_FW_F_OUT     0x00000200      /* Check outbound packets               */
 206 #define IP_FW_F_IIFACE  0x00000400      /* Apply inbound interface test         */
 207 #define IP_FW_F_OIFACE  0x00000800      /* Apply outbound interface test        */
 208
 209 #define IP_FW_F_PRN     0x00001000      /* Print if this rule matches           */
 210
 211 #define IP_FW_F_SRNG    0x00002000      /* The first two src ports are a min    *
 212                                          * and max range (stored in host byte   *
 213                                          * order).                              */
 214
 215 #define IP_FW_F_DRNG    0x00004000      /* The first two dst ports are a min    *
 216                                          * and max range (stored in host byte   *
 217                                          * order).                              */
 218
 219 #define IP_FW_F_FRAG    0x00008000      /* Fragment                             */
 220
 221 #define IP_FW_F_IIFNAME 0x00010000      /* In interface by name/unit (not IP)   */
 222 #define IP_FW_F_OIFNAME 0x00020000      /* Out interface by name/unit (not IP)  */
 223
 224 #define IP_FW_F_INVSRC  0x00040000      /* Invert sense of src check            */
 225 #define IP_FW_F_INVDST  0x00080000      /* Invert sense of dst check            */
 226
 227 #define IP_FW_F_ICMPBIT 0x00100000      /* ICMP type bitmap is valid            */
 228
 229 #define IP_FW_F_UID     0x00200000      /* filter by uid                        */
 230
 231 #define IP_FW_F_RND_MATCH 0x00800000    /* probabilistic rule match             */
 232 #define IP_FW_F_SMSK    0x01000000      /* src-port + mask                      */
 233 #define IP_FW_F_DMSK    0x02000000      /* dst-port + mask                      */
 234 #define IP_FW_BRIDGED   0x04000000      /* only match bridged packets           */
 235 #define IP_FW_F_KEEP_S  0x08000000      /* keep state                           */
 236 #define IP_FW_F_CHECK_S 0x10000000      /* check state                          */
 237
 238 #define IP_FW_F_SME     0x20000000      /* source = me                          */
 239 #define IP_FW_F_DME     0x40000000      /* destination = me                     */
 240
 241 #define IP_FW_F_MASK    0x7FFFFFFF      /* All possible flag bits mask          */
 242
 243 /*
 244  * Flags for the 'fw_ipflg' field, for comparing values of ip and its protocols.
 245  */
 246 #define IP_FW_IF_TCPEST 0x00000020      /* established TCP connection */
 247 #define IP_FW_IF_TCPMSK 0x00000020      /* mask of all TCP values */
 248
 249 /*
 250  * For backwards compatibility with rules specifying "via iface" but
 251  * not restricted to only "in" or "out" packets, we define this combination
 252  * of bits to represent this configuration.
 253  */
 254
 255 #define IF_FW_F_VIAHACK (IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
 256
 257 /*
 258  * Definitions for REJECT response codes.
 259  * Values less than 256 correspond to ICMP unreachable codes.
 260  */
 261 #define IP_FW_REJECT_RST        0x0100          /* TCP packets: send RST */
 262
 263 /*
 264  * Definitions for IP option names.
 265  */
 266 #define IP_FW_IPOPT_LSRR        0x01
 267 #define IP_FW_IPOPT_SSRR        0x02
 268 #define IP_FW_IPOPT_RR          0x04
 269 #define IP_FW_IPOPT_TS          0x08
 270
 271 /*
 272  * Definitions for TCP option names.
 273  */
 274 #define IP_FW_TCPOPT_MSS        0x01
 275 #define IP_FW_TCPOPT_WINDOW     0x02
 276 #define IP_FW_TCPOPT_SACK       0x04
 277 #define IP_FW_TCPOPT_TS         0x08
 278 #define IP_FW_TCPOPT_CC         0x10
 279
 280 /*
 281  * Definitions for TCP flags.
 282  */
 283 #define IP_FW_TCPF_FIN          TH_FIN
 284 #define IP_FW_TCPF_SYN          TH_SYN
 285 #define IP_FW_TCPF_RST          TH_RST
 286 #define IP_FW_TCPF_PSH          TH_PUSH
 287 #define IP_FW_TCPF_ACK          TH_ACK
 288 #define IP_FW_TCPF_URG          TH_URG
 289
 290 /*
 291  * Main firewall chains definitions and global var's definitions.
 292  */
 293 #ifdef KERNEL
 294 #ifdef __APPLE_API_PRIVATE
 295
 296 #define IP_FW_PORT_DYNT_FLAG    0x10000
 297 #define IP_FW_PORT_TEE_FLAG     0x20000
 298 #define IP_FW_PORT_DENY_FLAG    0x40000
 299
 300 /*
 301  * Function definitions.
 302  */
 303 void ip_fw_init __P((void));
 304
 305 /* Firewall hooks */
 306 struct ip;
 307 struct sockopt;
 308 typedef int ip_fw_chk_t __P((struct ip **, int, struct ifnet *, u_int16_t *,
 309              struct mbuf **, struct ip_fw_chain **, struct sockaddr_in **));
 310 typedef int ip_fw_ctl_t __P((struct sockopt *));
 311 extern  ip_fw_chk_t *ip_fw_chk_ptr;
 312 extern  ip_fw_ctl_t *ip_fw_ctl_ptr;
 313 extern int fw_one_pass;
 314 extern int fw_enable;
 315 extern struct ipfw_flow_id last_pkt ;
 316 #endif /* __APPLE_API_PRIVATE */
 317 #endif /* KERNEL */
 318
 319 #endif /* _IP_FW_H */