lib/ipaddr.h

   1 /*
   2  * IP address structure (for generic IPv4 or IPv6 address)
   3  * Copyright (C) 2016, 2017 Cumulus Networks, Inc.
   4  *
   5  * This file is part of FRR.
   6  *
   7  * FRR is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * FRR is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with FRR; see the file COPYING.  If not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20  * 02111-1307, USA.
  21  */
  22
  23 #ifndef __IPADDR_H__
  24 #define __IPADDR_H__
  25
  26 #include <zebra.h>
  27
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 /*
  33  * Generic IP address - union of IPv4 and IPv6 address.
  34  */
  35 enum ipaddr_type_t {
  36         IPADDR_NONE = 0,
  37         IPADDR_V4 = 1, /* IPv4 */
  38         IPADDR_V6 = 2, /* IPv6 */
  39 };
  40
  41 struct ipaddr {
  42         enum ipaddr_type_t ipa_type;
  43         union {
  44                 uint8_t addr;
  45                 struct in_addr _v4_addr;
  46                 struct in6_addr _v6_addr;
  47         } ip;
  48 #define ipaddr_v4 ip._v4_addr
  49 #define ipaddr_v6 ip._v6_addr
  50 };
  51
  52 #define IS_IPADDR_NONE(p) ((p)->ipa_type == IPADDR_NONE)
  53 #define IS_IPADDR_V4(p)   ((p)->ipa_type == IPADDR_V4)
  54 #define IS_IPADDR_V6(p)   ((p)->ipa_type == IPADDR_V6)
  55
  56 #define SET_IPADDR_V4(p)  (p)->ipa_type = IPADDR_V4
  57 #define SET_IPADDR_V6(p)  (p)->ipa_type = IPADDR_V6
  58
  59 #define IPADDRSZ(p)                                                            \
  60         (IS_IPADDR_V4((p)) ? sizeof(struct in_addr) : sizeof(struct in6_addr))
  61
  62 static inline int str2ipaddr(const char *str, struct ipaddr *ip)
  63 {
  64         int ret;
  65
  66         memset(ip, 0, sizeof(struct ipaddr));
  67
  68         ret = inet_pton(AF_INET, str, &ip->ipaddr_v4);
  69         if (ret > 0) /* Valid IPv4 address. */
  70         {
  71                 ip->ipa_type = IPADDR_V4;
  72                 return 0;
  73         }
  74         ret = inet_pton(AF_INET6, str, &ip->ipaddr_v6);
  75         if (ret > 0) /* Valid IPv6 address. */
  76         {
  77                 ip->ipa_type = IPADDR_V6;
  78                 return 0;
  79         }
  80
  81         return -1;
  82 }
  83
  84 static inline char *ipaddr2str(const struct ipaddr *ip, char *buf, int size)
  85 {
  86         buf[0] = '\0';
  87         if (ip) {
  88                 if (IS_IPADDR_V4(ip))
  89                         inet_ntop(AF_INET, &ip->ip.addr, buf, size);
  90                 else if (IS_IPADDR_V6(ip))
  91                         inet_ntop(AF_INET6, &ip->ip.addr, buf, size);
  92         }
  93         return buf;
  94 }
  95
  96 /*
  97  * Convert IPv4 address to IPv4-mapped IPv6 address which is of the
  98  * form ::FFFF:<IPv4 address> (RFC 4291). This IPv6 address can then
  99  * be used to represent the IPv4 address, wherever only an IPv6 address
 100  * is required.
 101  */
 102 static inline void ipv4_to_ipv4_mapped_ipv6(struct in6_addr *in6,
 103                                             struct in_addr in)
 104 {
 105         uint32_t addr_type = htonl(0xFFFF);
 106
 107         memset(in6, 0, sizeof(struct in6_addr));
 108         memcpy((char *)in6 + 8, &addr_type, sizeof(addr_type));
 109         memcpy((char *)in6 + 12, &in, sizeof(struct in_addr));
 110 }
 111
 112 /*
 113  * convert an ipv4 mapped ipv6 address back to ipv4 address
 114  */
 115 static inline void ipv4_mapped_ipv6_to_ipv4(struct in6_addr *in6,
 116                                             struct in_addr *in)
 117 {
 118         memset(in, 0, sizeof(struct in_addr));
 119         memcpy(in, (char *)in6 + 12, sizeof(struct in_addr));
 120 }
 121
 122 #ifdef __cplusplus
 123 }
 124 #endif
 125
 126 #endif /* __IPADDR_H__ */