bsd/netinet6/ip6_fw.h

   1 /*
   2  * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * Copyright (c) 1993 Daniel Boulet
  32  * Copyright (c) 1994 Ugen J.S.Antsilevich
  33  *
  34  * Redistribution and use in source forms, with and without modification,
  35  * are permitted provided that this entire comment appears intact.
  36  *
  37  * Redistribution in binary form may occur without any restrictions.
  38  * Obviously, it would be nice if you gave credit where credit is due
  39  * but requiring it would be too onerous.
  40  *
  41  * This software is provided ``AS IS'' without any warranties of any kind.
  42  *
  43  */
  44
  45 #ifndef _IP6_FW_H
  46 #define _IP6_FW_H
  47 #include <sys/appleapiopts.h>
  48
  49 #include <net/if.h>
  50
  51 #define IPV6_FW_CURRENT_API_VERSION 20  /* Version of this API */
  52
  53
  54 /*
  55  * This union structure identifies an interface, either explicitly
  56  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
  57  * and IP_FW_F_OIFNAME say how to interpret this structure. An
  58  * interface unit number of -1 matches any unit number, while an
  59  * IP address of 0.0.0.0 indicates matches any interface.
  60  *
  61  * The receive and transmit interfaces are only compared against the
  62  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
  63  * is set. Note some packets lack a receive or transmit interface
  64  * (in which case the missing "interface" never matches).
  65  */
  66
  67 union ip6_fw_if {
  68     struct in6_addr fu_via_ip6; /* Specified by IPv6 address */
  69     struct {                    /* Specified by interface name */
  70 #define IP6FW_IFNLEN     IFNAMSIZ
  71             char  name[IP6FW_IFNLEN];
  72             short unit;         /* -1 means match any unit */
  73     } fu_via_if;
  74 };
  75
  76 /*
  77  * Format of an IP firewall descriptor
  78  *
  79  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
  80  * fw_flg and fw_n*p are stored in host byte order (of course).
  81  * Port numbers are stored in HOST byte order.
  82  * Warning: setsockopt() will fail if sizeof(struct ip_fw) > MLEN (108)
  83  */
  84
  85 struct ip6_fw {
  86         u_int32_t version;              /* Version of this structure.  Should always be */
  87                                                         /* set to IP6_FW_CURRENT_API_VERSION by clients. */
  88         void *context;                  /* Context that is usable by user processes to */
  89                                                         /* identify this rule. */
  90     u_long fw_pcnt,fw_bcnt;             /* Packet and byte counters */
  91     struct in6_addr fw_src, fw_dst;     /* Source and destination IPv6 addr */
  92     struct in6_addr fw_smsk, fw_dmsk;   /* Mask for src and dest IPv6 addr */
  93     u_short fw_number;                  /* Rule number */
  94     u_short fw_flg;                     /* Flags word */
  95 #define IPV6_FW_MAX_PORTS       10      /* A reasonable maximum */
  96     u_int fw_ipflg;                     /* IP flags word */
  97     u_short fw_pts[IPV6_FW_MAX_PORTS];  /* Array of port numbers to match */
  98     u_char fw_ip6opt,fw_ip6nopt;        /* IPv6 options set/unset */
  99     u_char fw_tcpf,fw_tcpnf;            /* TCP flags set/unset */
 100 #define IPV6_FW_ICMPTYPES_DIM (256 / (sizeof(unsigned) * 8))
 101     unsigned fw_icmp6types[IPV6_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
 102     long timestamp;                     /* timestamp (tv_sec) of last match */
 103     union ip6_fw_if fw_in_if, fw_out_if;/* Incoming and outgoing interfaces */
 104     union {
 105         u_short fu_divert_port;         /* Divert/tee port (options IP6DIVERT) */
 106         u_short fu_skipto_rule;         /* SKIPTO command rule number */
 107         u_short fu_reject_code;         /* REJECT response code */
 108     } fw_un;
 109     u_char fw_prot;                     /* IPv6 protocol */
 110     u_char fw_nports;                   /* N'of src ports and # of dst ports */
 111                                         /* in ports array (dst ports follow */
 112                                         /* src ports; max of 10 ports in all; */
 113                                         /* count of 0 means match all ports) */
 114 };
 115
 116 #define IPV6_FW_GETNSRCP(rule)          ((rule)->fw_nports & 0x0f)
 117 #define IPV6_FW_SETNSRCP(rule, n)               do {                            \
 118                                           (rule)->fw_nports &= ~0x0f;   \
 119                                           (rule)->fw_nports |= (n);     \
 120                                         } while (0)
 121 #define IPV6_FW_GETNDSTP(rule)          ((rule)->fw_nports >> 4)
 122 #define IPV6_FW_SETNDSTP(rule, n)               do {                            \
 123                                           (rule)->fw_nports &= ~0xf0;   \
 124                                           (rule)->fw_nports |= (n) << 4;\
 125                                         } while (0)
 126
 127 #define fw_divert_port  fw_un.fu_divert_port
 128 #define fw_skipto_rule  fw_un.fu_skipto_rule
 129 #define fw_reject_code  fw_un.fu_reject_code
 130
 131 struct ip6_fw_chain {
 132         LIST_ENTRY(ip6_fw_chain) chain;
 133         struct ip6_fw    *rule;
 134 };
 135
 136 /*
 137  * Values for "flags" field .
 138  */
 139 #define IPV6_FW_F_IN    0x0001  /* Check inbound packets                */
 140 #define IPV6_FW_F_OUT   0x0002  /* Check outbound packets               */
 141 #define IPV6_FW_F_IIFACE        0x0004  /* Apply inbound interface test         */
 142 #define IPV6_FW_F_OIFACE        0x0008  /* Apply outbound interface test        */
 143
 144 #define IPV6_FW_F_COMMAND 0x0070        /* Mask for type of chain entry:        */
 145 #define IPV6_FW_F_DENY  0x0000  /* This is a deny rule                  */
 146 #define IPV6_FW_F_REJECT        0x0010  /* Deny and send a response packet      */
 147 #define IPV6_FW_F_ACCEPT        0x0020  /* This is an accept rule               */
 148 #define IPV6_FW_F_COUNT 0x0030  /* This is a count rule                 */
 149 #define IPV6_FW_F_DIVERT        0x0040  /* This is a divert rule                */
 150 #define IPV6_FW_F_TEE   0x0050  /* This is a tee rule                   */
 151 #define IPV6_FW_F_SKIPTO        0x0060  /* This is a skipto rule                */
 152
 153 #define IPV6_FW_F_PRN   0x0080  /* Print if this rule matches           */
 154
 155 #define IPV6_FW_F_SRNG  0x0100  /* The first two src ports are a min    *
 156                                  * and max range (stored in host byte   *
 157                                  * order).                              */
 158
 159 #define IPV6_FW_F_DRNG  0x0200  /* The first two dst ports are a min    *
 160                                  * and max range (stored in host byte   *
 161                                  * order).                              */
 162
 163 #define IPV6_FW_F_IIFNAME       0x0400  /* In interface by name/unit (not IP)   */
 164 #define IPV6_FW_F_OIFNAME       0x0800  /* Out interface by name/unit (not IP)  */
 165
 166 #define IPV6_FW_F_INVSRC        0x1000  /* Invert sense of src check            */
 167 #define IPV6_FW_F_INVDST        0x2000  /* Invert sense of dst check            */
 168
 169 #define IPV6_FW_F_FRAG  0x4000  /* Fragment                             */
 170
 171 #define IPV6_FW_F_ICMPBIT 0x8000        /* ICMP type bitmap is valid            */
 172
 173 #define IPV6_FW_F_MASK  0xFFFF  /* All possible flag bits mask          */
 174
 175 /*
 176  * Flags for the 'fw_ipflg' field, for comparing values of ip and its protocols. */
 177 #define IPV6_FW_IF_TCPEST 0x00000020    /* established TCP connection   */
 178 #define IPV6_FW_IF_TCPMSK 0x00000020    /* mask of all TCP values */
 179
 180 /*
 181  * For backwards compatibility with rules specifying "via iface" but
 182  * not restricted to only "in" or "out" packets, we define this combination
 183  * of bits to represent this configuration.
 184  */
 185
 186 #define IF6_FW_F_VIAHACK        (IPV6_FW_F_IN|IPV6_FW_F_OUT|IPV6_FW_F_IIFACE|IPV6_FW_F_OIFACE)
 187
 188 /*
 189  * Definitions for REJECT response codes.
 190  * Values less than 256 correspond to ICMP unreachable codes.
 191  */
 192 #define IPV6_FW_REJECT_RST      0x0100          /* TCP packets: send RST */
 193
 194 /*
 195  * Definitions for IPv6 option names.
 196  */
 197 #define IPV6_FW_IP6OPT_HOPOPT   0x01
 198 #define IPV6_FW_IP6OPT_ROUTE    0x02
 199 #define IPV6_FW_IP6OPT_FRAG     0x04
 200 #define IPV6_FW_IP6OPT_ESP      0x08
 201 #define IPV6_FW_IP6OPT_AH       0x10
 202 #define IPV6_FW_IP6OPT_NONXT    0x20
 203 #define IPV6_FW_IP6OPT_OPTS     0x40
 204
 205 /*
 206  * Definitions for TCP flags.
 207  */
 208 #define IPV6_FW_TCPF_FIN        TH_FIN
 209 #define IPV6_FW_TCPF_SYN        TH_SYN
 210 #define IPV6_FW_TCPF_RST        TH_RST
 211 #define IPV6_FW_TCPF_PSH        TH_PUSH
 212 #define IPV6_FW_TCPF_ACK        TH_ACK
 213 #define IPV6_FW_TCPF_URG        TH_URG
 214
 215 /*
 216  * Main firewall chains definitions and global var's definitions.
 217  */
 218 #ifdef KERNEL_PRIVATE
 219
 220 #define M_IP6FW M_IPFW
 221
 222
 223 /*
 224  * Function definitions.
 225  */
 226 void ip6_fw_init(void);
 227
 228 /* Firewall hooks */
 229 struct ip6_hdr;
 230 struct sockopt;
 231 typedef int ip6_fw_chk_t(struct ip6_hdr**, struct ifnet*,
 232                                 u_short *, struct mbuf**);
 233 typedef int ip6_fw_ctl_t(struct sockopt *);
 234 extern  ip6_fw_chk_t *ip6_fw_chk_ptr;
 235 extern  ip6_fw_ctl_t *ip6_fw_ctl_ptr;
 236 extern  int ip6_fw_enable;
 237
 238 #endif /* KERNEL_PRIVATE */
 239
 240 #endif /* _IP6_FW_H */