bsd/netinet/ip_fw.h

   1 /*
   2  * Copyright (c) 2000 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
  40 #include <sys/queue.h>
  41
  42 /*
  43  * This union structure identifies an interface, either explicitly
  44  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
  45  * and IP_FW_F_OIFNAME say how to interpret this structure. An
  46  * interface unit number of -1 matches any unit number, while an
  47  * IP address of 0.0.0.0 indicates matches any interface.
  48  *
  49  * The receive and transmit interfaces are only compared against the
  50  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
  51  * is set. Note some packets lack a receive or transmit interface
  52  * (in which case the missing "interface" never matches).
  53  */
  54
  55 union ip_fw_if {
  56     struct in_addr fu_via_ip;   /* Specified by IP address */
  57     struct {                    /* Specified by interface name */
  58 #define FW_IFNLEN     10 /* need room ! was IFNAMSIZ */
  59             char  name[FW_IFNLEN];
  60             short unit;         /* -1 means match any unit */
  61     } fu_via_if;
  62 };
  63
  64 /*
  65  * Format of an IP firewall descriptor
  66  *
  67  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
  68  * fw_flg and fw_n*p are stored in host byte order (of course).
  69  * Port numbers are stored in HOST byte order.
  70  * Warning: setsockopt() will fail if sizeof(struct ip_fw) > MLEN (108)
  71  */
  72
  73 struct ip_fw {
  74     u_int64_t fw_pcnt,fw_bcnt;          /* Packet and byte counters */
  75     struct in_addr fw_src, fw_dst;      /* Source and destination IP addr */
  76     struct in_addr fw_smsk, fw_dmsk;    /* Mask for src and dest IP addr */
  77     u_short fw_number;                  /* Rule number */
  78     u_int fw_flg;                       /* Flags word */
  79 #define IP_FW_MAX_PORTS 10              /* A reasonable maximum */
  80         union {
  81         u_short fw_pts[IP_FW_MAX_PORTS];        /* Array of port numbers to match */
  82 #define IP_FW_ICMPTYPES_MAX     128
  83 #define IP_FW_ICMPTYPES_DIM     (IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
  84         unsigned fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
  85         } fw_uar;
  86     u_char fw_ipopt,fw_ipnopt;          /* IP options set/unset */
  87     u_char fw_tcpf,fw_tcpnf;            /* TCP flags set/unset */
  88     long timestamp;                     /* timestamp (tv_sec) of last match */
  89     union ip_fw_if fw_in_if, fw_out_if; /* Incoming and outgoing interfaces */
  90     union {
  91         u_short fu_divert_port;         /* Divert/tee port (options IPDIVERT) */
  92         u_short fu_pipe_nr;             /* pipe number (option DUMMYNET) */
  93         u_short fu_skipto_rule;         /* SKIPTO command rule number */
  94         u_short fu_reject_code;         /* REJECT response code */
  95         struct sockaddr_in fu_fwd_ip;
  96     } fw_un;
  97     u_char fw_prot;                     /* IP protocol */
  98     u_char fw_nports;                   /* N'of src ports and # of dst ports */
  99                                         /* in ports array (dst ports follow */
 100                                         /* src ports; max of 10 ports in all; */
 101                                         /* count of 0 means match all ports) */
 102     void *pipe_ptr;                    /* Pipe ptr in case of dummynet pipe */
 103     void *next_rule_ptr ;              /* next rule in case of match */
 104 };
 105
 106 #define IP_FW_GETNSRCP(rule)            ((rule)->fw_nports & 0x0f)
 107 #define IP_FW_SETNSRCP(rule, n)         do {                            \
 108                                           (rule)->fw_nports &= ~0x0f;   \
 109                                           (rule)->fw_nports |= (n);     \
 110                                         } while (0)
 111 #define IP_FW_GETNDSTP(rule)            ((rule)->fw_nports >> 4)
 112 #define IP_FW_SETNDSTP(rule, n)         do {                            \
 113                                           (rule)->fw_nports &= ~0xf0;   \
 114                                           (rule)->fw_nports |= (n) << 4;\
 115                                         } while (0)
 116
 117 #define fw_divert_port  fw_un.fu_divert_port
 118 #define fw_skipto_rule  fw_un.fu_skipto_rule
 119 #define fw_reject_code  fw_un.fu_reject_code
 120 #define fw_pipe_nr      fw_un.fu_pipe_nr
 121 #define fw_fwd_ip       fw_un.fu_fwd_ip
 122
 123 struct ip_fw_chain {
 124         LIST_ENTRY(ip_fw_chain) chain;
 125         struct ip_fw    *rule;
 126 };
 127
 128 /*
 129  * Values for "flags" field .
 130  */
 131 #define IP_FW_F_COMMAND 0x000000ff      /* Mask for type of chain entry:        */
 132 #define IP_FW_F_DENY    0x00000000      /* This is a deny rule                  */
 133 #define IP_FW_F_REJECT  0x00000001      /* Deny and send a response packet      */
 134 #define IP_FW_F_ACCEPT  0x00000002      /* This is an accept rule               */
 135 #define IP_FW_F_COUNT   0x00000003      /* This is a count rule                 */
 136 #define IP_FW_F_DIVERT  0x00000004      /* This is a divert rule                */
 137 #define IP_FW_F_TEE     0x00000005      /* This is a tee rule                   */
 138 #define IP_FW_F_SKIPTO  0x00000006      /* This is a skipto rule                */
 139 #define IP_FW_F_FWD     0x00000007      /* This is a "change forwarding address" rule */
 140 #define IP_FW_F_PIPE    0x00000008      /* This is a dummynet rule */
 141
 142 #define IP_FW_F_IN      0x00000100      /* Check inbound packets                */
 143 #define IP_FW_F_OUT     0x00000200      /* Check outbound packets               */
 144 #define IP_FW_F_IIFACE  0x00000400      /* Apply inbound interface test         */
 145 #define IP_FW_F_OIFACE  0x00000800      /* Apply outbound interface test        */
 146
 147 #define IP_FW_F_PRN     0x00001000      /* Print if this rule matches           */
 148
 149 #define IP_FW_F_SRNG    0x00002000      /* The first two src ports are a min    *
 150                                          * and max range (stored in host byte   *
 151                                          * order).                              */
 152
 153 #define IP_FW_F_DRNG    0x00004000      /* The first two dst ports are a min    *
 154                                          * and max range (stored in host byte   *
 155                                          * order).                              */
 156
 157 #define IP_FW_F_FRAG    0x00008000      /* Fragment                             */
 158
 159 #define IP_FW_F_IIFNAME 0x00010000      /* In interface by name/unit (not IP)   */
 160 #define IP_FW_F_OIFNAME 0x00020000      /* Out interface by name/unit (not IP)  */
 161
 162 #define IP_FW_F_INVSRC  0x00040000      /* Invert sense of src check            */
 163 #define IP_FW_F_INVDST  0x00080000      /* Invert sense of dst check            */
 164
 165 #define IP_FW_F_ICMPBIT 0x00100000      /* ICMP type bitmap is valid            */
 166
 167 #define IP_FW_F_MASK    0x001FFFFF      /* All possible flag bits mask          */
 168
 169 /*
 170  * For backwards compatibility with rules specifying "via iface" but
 171  * not restricted to only "in" or "out" packets, we define this combination
 172  * of bits to represent this configuration.
 173  */
 174
 175 #define IF_FW_F_VIAHACK (IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
 176
 177 /*
 178  * Definitions for REJECT response codes.
 179  * Values less than 256 correspond to ICMP unreachable codes.
 180  */
 181 #define IP_FW_REJECT_RST        0x0100          /* TCP packets: send RST */
 182
 183 /*
 184  * Definitions for IP option names.
 185  */
 186 #define IP_FW_IPOPT_LSRR        0x01
 187 #define IP_FW_IPOPT_SSRR        0x02
 188 #define IP_FW_IPOPT_RR          0x04
 189 #define IP_FW_IPOPT_TS          0x08
 190
 191 /*
 192  * Definitions for TCP flags.
 193  */
 194 #define IP_FW_TCPF_FIN          TH_FIN
 195 #define IP_FW_TCPF_SYN          TH_SYN
 196 #define IP_FW_TCPF_RST          TH_RST
 197 #define IP_FW_TCPF_PSH          TH_PUSH
 198 #define IP_FW_TCPF_ACK          TH_ACK
 199 #define IP_FW_TCPF_URG          TH_URG
 200 #define IP_FW_TCPF_ESTAB        0x40
 201
 202 /*
 203  * Main firewall chains definitions and global var's definitions.
 204  */
 205 #ifdef KERNEL
 206
 207 /*
 208  * Function definitions.
 209  */
 210 void ip_fw_init __P((void));
 211
 212 /* Firewall hooks */
 213 struct ip;
 214 struct sockopt;
 215 typedef int ip_fw_chk_t __P((struct ip **, int, struct ifnet *, u_int16_t *,
 216              struct mbuf **, struct ip_fw_chain **, struct sockaddr_in **));
 217 typedef int ip_fw_ctl_t __P((struct sockopt *));
 218 extern  ip_fw_chk_t *ip_fw_chk_ptr;
 219 extern  ip_fw_ctl_t *ip_fw_ctl_ptr;
 220
 221 /* IP NAT hooks */
 222 typedef int ip_nat_t __P((struct ip **, struct mbuf **, struct ifnet *, int));
 223 typedef int ip_nat_ctl_t __P((struct sockopt *));
 224 extern  ip_nat_t *ip_nat_ptr;
 225 extern  ip_nat_ctl_t *ip_nat_ctl_ptr;
 226 #define IP_NAT_IN       0x00000001
 227 #define IP_NAT_OUT      0x00000002
 228
 229 #endif /* KERNEL */
 230
 231 #endif /* _IP_FW_H */