bsd/netinet/ip_fw.h

   1 /*
   2  * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1993 Daniel Boulet
  24  * Copyright (c) 1994 Ugen J.S.Antsilevich
  25  *
  26  * Redistribution and use in source forms, with and without modification,
  27  * are permitted provided that this entire comment appears intact.
  28  *
  29  * Redistribution in binary form may occur without any restrictions.
  30  * Obviously, it would be nice if you gave credit where credit is due
  31  * but requiring it would be too onerous.
  32  *
  33  * This software is provided ``AS IS'' without any warranties of any kind.
  34  *
  35  */
  36
  37 #ifndef _IP_FW_H
  38 #define _IP_FW_H
  39 #include <sys/appleapiopts.h>
  40
  41 #include <sys/queue.h>
  42
  43
  44 #define IP_FW_CURRENT_API_VERSION 20    /* Version of this API */
  45
  46
  47 /*
  48  * This union structure identifies an interface, either explicitly
  49  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
  50  * and IP_FW_F_OIFNAME say how to interpret this structure. An
  51  * interface unit number of -1 matches any unit number, while an
  52  * IP address of 0.0.0.0 indicates matches any interface.
  53  *
  54  * The receive and transmit interfaces are only compared against the
  55  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
  56  * is set. Note some packets lack a receive or transmit interface
  57  * (in which case the missing "interface" never matches).
  58  */
  59
  60 union ip_fw_if {
  61     struct in_addr fu_via_ip;   /* Specified by IP address */
  62     struct {                    /* Specified by interface name */
  63 #define FW_IFNLEN     10 /* need room ! was IFNAMSIZ */
  64             char  name[FW_IFNLEN];
  65             short unit;         /* -1 means match any unit */
  66     } fu_via_if;
  67 };
  68
  69 /*
  70  * Format of an IP firewall descriptor
  71  *
  72  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
  73  * fw_flg and fw_n*p are stored in host byte order (of course).
  74  * Port numbers are stored in HOST byte order.
  75  */
  76
  77 struct ip_fw {
  78         u_int32_t version;              /* Version of this structure.  Should always be */
  79                                                         /* set to IP_FW_CURRENT_API_VERSION by clients. */
  80         void *context;                  /* Context that is usable by user processes to */
  81                                                         /* identify this rule. */
  82     u_int64_t fw_pcnt,fw_bcnt;          /* Packet and byte counters */
  83     struct in_addr fw_src, fw_dst;      /* Source and destination IP addr */
  84     struct in_addr fw_smsk, fw_dmsk;    /* Mask for src and dest IP addr */
  85     u_short fw_number;                  /* Rule number */
  86     u_int fw_flg;                       /* Flags word */
  87 #define IP_FW_MAX_PORTS 10              /* A reasonable maximum */
  88         union {
  89         u_short fw_pts[IP_FW_MAX_PORTS];        /* Array of port numbers to match */
  90 #define IP_FW_ICMPTYPES_MAX     128
  91 #define IP_FW_ICMPTYPES_DIM     (IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
  92         unsigned fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
  93         } fw_uar;
  94     u_int fw_ipflg;                     /* IP flags word */
  95     u_char fw_ipopt,fw_ipnopt;          /* IP options set/unset */
  96     u_char fw_tcpopt,fw_tcpnopt;        /* TCP options set/unset */
  97     u_char fw_tcpf,fw_tcpnf;            /* TCP flags set/unset */
  98     long timestamp;                     /* timestamp (tv_sec) of last match */
  99     union ip_fw_if fw_in_if, fw_out_if; /* Incoming and outgoing interfaces */
 100     union {
 101         u_short fu_divert_port;         /* Divert/tee port (options IPDIVERT) */
 102         u_short fu_pipe_nr;             /* queue number (option DUMMYNET) */
 103         u_short fu_skipto_rule;         /* SKIPTO command rule number */
 104         u_short fu_reject_code;         /* REJECT response code */
 105         struct sockaddr_in fu_fwd_ip;
 106     } fw_un;
 107     u_char fw_prot;                     /* IP protocol */
 108         /*
 109          * N'of src ports and # of dst ports in ports array (dst ports
 110          * follow src ports; max of 10 ports in all; count of 0 means
 111          * match all ports)
 112          */
 113     u_char fw_nports;
 114     void *pipe_ptr;                    /* flow_set ptr for dummynet pipe */
 115     void *next_rule_ptr ;              /* next rule in case of match */
 116     uid_t fw_uid;                       /* uid to match */
 117     int fw_logamount;                   /* amount to log */
 118     u_int64_t fw_loghighest;            /* highest number packet to log */
 119 };
 120
 121 /*
 122  * extended ipfw structure... some fields in the original struct
 123  * can be used to pass parameters up/down, namely pointers
 124  *     void *pipe_ptr
 125  *     void *next_rule_ptr
 126  * some others can be used to pass parameters down, namely counters etc.
 127  *     u_int64_t fw_pcnt,fw_bcnt;
 128  *     long timestamp;
 129  */
 130
 131 struct ip_fw_ext {             /* extended structure */
 132     struct ip_fw rule;      /* must be at offset 0 */
 133     long    dont_match_prob;        /* 0x7fffffff means 1.0, always fail */
 134     u_int   dyn_type;  /* type for dynamic rule */
 135 };
 136
 137 #define IP_FW_GETNSRCP(rule)            ((rule)->fw_nports & 0x0f)
 138 #define IP_FW_SETNSRCP(rule, n)         do {                            \
 139                                           (rule)->fw_nports &= ~0x0f;   \
 140                                           (rule)->fw_nports |= (n);     \
 141                                         } while (0)
 142 #define IP_FW_GETNDSTP(rule)            ((rule)->fw_nports >> 4)
 143 #define IP_FW_SETNDSTP(rule, n)         do {                            \
 144                                           (rule)->fw_nports &= ~0xf0;   \
 145                                           (rule)->fw_nports |= (n) << 4;\
 146                                         } while (0)
 147
 148 #define fw_divert_port  fw_un.fu_divert_port
 149 #define fw_skipto_rule  fw_un.fu_skipto_rule
 150 #define fw_reject_code  fw_un.fu_reject_code
 151 #define fw_pipe_nr      fw_un.fu_pipe_nr
 152 #define fw_fwd_ip       fw_un.fu_fwd_ip
 153
 154 struct ip_fw_chain {
 155         LIST_ENTRY(ip_fw_chain) next;
 156         struct ip_fw *rule;
 157 };
 158
 159 /*
 160  * Flow mask/flow id for each queue.
 161  */
 162 struct ipfw_flow_id {
 163     u_int32_t dst_ip, src_ip ;
 164     u_int16_t dst_port, src_port ;
 165     u_int8_t proto ;
 166     u_int8_t flags ;    /* protocol-specific flags */
 167 } ;
 168
 169 /*
 170  * dynamic ipfw rule
 171  */
 172 struct ipfw_dyn_rule {
 173     struct ipfw_dyn_rule *next ;
 174
 175     struct ipfw_flow_id id ;
 176     struct ipfw_flow_id mask ;
 177     struct ip_fw_chain *chain ;         /* pointer to parent rule       */
 178     u_int32_t type ;                    /* rule type                    */
 179     u_int32_t expire ;                  /* expire time                  */
 180     u_int64_t pcnt, bcnt;               /* match counters               */
 181     u_int32_t bucket ;                  /* which bucket in hash table   */
 182     u_int32_t state ;                   /* state of this rule (typ. a   */
 183                                         /* combination of TCP flags)    */
 184 } ;
 185
 186 /*
 187  * Values for "flags" field .
 188  */
 189 #define IP_FW_F_COMMAND 0x000000ff      /* Mask for type of chain entry:        */
 190 #define IP_FW_F_DENY    0x00000000      /* This is a deny rule                  */
 191 #define IP_FW_F_REJECT  0x00000001      /* Deny and send a response packet      */
 192 #define IP_FW_F_ACCEPT  0x00000002      /* This is an accept rule               */
 193 #define IP_FW_F_COUNT   0x00000003      /* This is a count rule                 */
 194 #define IP_FW_F_DIVERT  0x00000004      /* This is a divert rule                */
 195 #define IP_FW_F_TEE     0x00000005      /* This is a tee rule                   */
 196 #define IP_FW_F_SKIPTO  0x00000006      /* This is a skipto rule                */
 197 #define IP_FW_F_FWD     0x00000007      /* This is a "change forwarding address" rule */
 198 #define IP_FW_F_PIPE    0x00000008      /* This is a dummynet rule */
 199 #define IP_FW_F_QUEUE   0x00000009      /* This is a dummynet queue */
 200
 201 #define IP_FW_F_IN      0x00000100      /* Check inbound packets                */
 202 #define IP_FW_F_OUT     0x00000200      /* Check outbound packets               */
 203 #define IP_FW_F_IIFACE  0x00000400      /* Apply inbound interface test         */
 204 #define IP_FW_F_OIFACE  0x00000800      /* Apply outbound interface test        */
 205
 206 #define IP_FW_F_PRN     0x00001000      /* Print if this rule matches           */
 207
 208 #define IP_FW_F_SRNG    0x00002000      /* The first two src ports are a min    *
 209                                          * and max range (stored in host byte   *
 210                                          * order).                              */
 211
 212 #define IP_FW_F_DRNG    0x00004000      /* The first two dst ports are a min    *
 213                                          * and max range (stored in host byte   *
 214                                          * order).                              */
 215
 216 #define IP_FW_F_FRAG    0x00008000      /* Fragment                             */
 217
 218 #define IP_FW_F_IIFNAME 0x00010000      /* In interface by name/unit (not IP)   */
 219 #define IP_FW_F_OIFNAME 0x00020000      /* Out interface by name/unit (not IP)  */
 220
 221 #define IP_FW_F_INVSRC  0x00040000      /* Invert sense of src check            */
 222 #define IP_FW_F_INVDST  0x00080000      /* Invert sense of dst check            */
 223
 224 #define IP_FW_F_ICMPBIT 0x00100000      /* ICMP type bitmap is valid            */
 225
 226 #define IP_FW_F_UID     0x00200000      /* filter by uid                        */
 227
 228 #define IP_FW_F_RND_MATCH 0x00800000    /* probabilistic rule match             */
 229 #define IP_FW_F_SMSK    0x01000000      /* src-port + mask                      */
 230 #define IP_FW_F_DMSK    0x02000000      /* dst-port + mask                      */
 231 #define IP_FW_BRIDGED   0x04000000      /* only match bridged packets           */
 232 #define IP_FW_F_KEEP_S  0x08000000      /* keep state                           */
 233 #define IP_FW_F_CHECK_S 0x10000000      /* check state                          */
 234
 235 #define IP_FW_F_SME     0x20000000      /* source = me                          */
 236 #define IP_FW_F_DME     0x40000000      /* destination = me                     */
 237
 238 #define IP_FW_F_MASK    0x7FFFFFFF      /* All possible flag bits mask          */
 239
 240 /*
 241  * Flags for the 'fw_ipflg' field, for comparing values of ip and its protocols.
 242  */
 243 #define IP_FW_IF_TCPEST 0x00000020      /* established TCP connection */
 244 #define IP_FW_IF_TCPMSK 0x00000020      /* mask of all TCP values */
 245
 246 /*
 247  * For backwards compatibility with rules specifying "via iface" but
 248  * not restricted to only "in" or "out" packets, we define this combination
 249  * of bits to represent this configuration.
 250  */
 251
 252 #define IF_FW_F_VIAHACK (IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
 253
 254 /*
 255  * Definitions for REJECT response codes.
 256  * Values less than 256 correspond to ICMP unreachable codes.
 257  */
 258 #define IP_FW_REJECT_RST        0x0100          /* TCP packets: send RST */
 259
 260 /*
 261  * Definitions for IP option names.
 262  */
 263 #define IP_FW_IPOPT_LSRR        0x01
 264 #define IP_FW_IPOPT_SSRR        0x02
 265 #define IP_FW_IPOPT_RR          0x04
 266 #define IP_FW_IPOPT_TS          0x08
 267
 268 /*
 269  * Definitions for TCP option names.
 270  */
 271 #define IP_FW_TCPOPT_MSS        0x01
 272 #define IP_FW_TCPOPT_WINDOW     0x02
 273 #define IP_FW_TCPOPT_SACK       0x04
 274 #define IP_FW_TCPOPT_TS         0x08
 275 #define IP_FW_TCPOPT_CC         0x10
 276
 277 /*
 278  * Definitions for TCP flags.
 279  */
 280 #define IP_FW_TCPF_FIN          TH_FIN
 281 #define IP_FW_TCPF_SYN          TH_SYN
 282 #define IP_FW_TCPF_RST          TH_RST
 283 #define IP_FW_TCPF_PSH          TH_PUSH
 284 #define IP_FW_TCPF_ACK          TH_ACK
 285 #define IP_FW_TCPF_URG          TH_URG
 286
 287 /*
 288  * Main firewall chains definitions and global var's definitions.
 289  */
 290 #ifdef KERNEL
 291 #ifdef __APPLE_API_PRIVATE
 292
 293 #define IP_FW_PORT_DYNT_FLAG    0x10000
 294 #define IP_FW_PORT_TEE_FLAG     0x20000
 295 #define IP_FW_PORT_DENY_FLAG    0x40000
 296
 297 /*
 298  * Function definitions.
 299  */
 300 void ip_fw_init __P((void));
 301
 302 /* Firewall hooks */
 303 struct ip;
 304 struct sockopt;
 305 typedef int ip_fw_chk_t __P((struct ip **, int, struct ifnet *, u_int16_t *,
 306              struct mbuf **, struct ip_fw_chain **, struct sockaddr_in **));
 307 typedef int ip_fw_ctl_t __P((struct sockopt *));
 308 extern  ip_fw_chk_t *ip_fw_chk_ptr;
 309 extern  ip_fw_ctl_t *ip_fw_ctl_ptr;
 310 extern int fw_one_pass;
 311 extern int fw_enable;
 312 extern struct ipfw_flow_id last_pkt ;
 313 #endif /* __APPLE_API_PRIVATE */
 314 #endif /* KERNEL */
 315
 316 #endif /* _IP_FW_H */