mdw@git.distorted.org.uk Git - yaid/blob - addr.c

   1 /* -*-c-*-
   2  *
   3  * Address-type specific functionality
   4  *
   5  * (c) 2012 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Yet Another Ident Daemon (YAID).
  11  *
  12  * YAID is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * YAID is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with YAID; if not, write to the Free Software Foundation,
  24  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25  */
  26
  27 /*----- Header files ------------------------------------------------------*/
  28
  29 #include "yaid.h"
  30
  31 /*----- IPv4 addresses ----------------------------------------------------*/
  32
  33 #define ADDRFAM_IPV4 AF_INET
  34 #define NAME_IPV4 "IPv4"
  35 #define ADDRLEN_IPV4 32
  36
  37 static int addreq_ipv4(const union addr *a, const union addr *b)
  38   { return a->ipv4.s_addr == b->ipv4.s_addr; }
  39
  40 static int match_addrpat_ipv4(const struct addrpat *ap, const union addr *a)
  41 {
  42   unsigned m;
  43
  44   if (!ap->len) return (1);
  45   m = htonl((MASK32 << (32 - ap->len)) & MASK32);
  46   return (((ap->addr.ipv4.s_addr ^ a->ipv4.s_addr) & m) == 0);
  47 }
  48
  49 static void socket_to_sockaddr_ipv4(const struct socket *s,
  50                                     void *sa, size_t *ssz)
  51 {
  52   struct sockaddr_in *sin = sa;
  53
  54   sin->sin_family = AF_INET;
  55   sin->sin_addr = s->addr.ipv4;
  56   sin->sin_port = htons(s->port);
  57   *ssz = sizeof(*sin);
  58 }
  59
  60 static void sockaddr_to_addr_ipv4(const void *sa, union addr *a)
  61   { const struct sockaddr_in *sin = sa; a->ipv4 = sin->sin_addr; }
  62
  63 static int init_listen_socket_ipv4(int fd) { return (0); }
  64
  65 static const union addr any_ipv4 = { .ipv4.s_addr = INADDR_ANY };
  66
  67 /*----- IPv6 addresses ----------------------------------------------------*/
  68
  69 #define ADDRFAM_IPV6 AF_INET6
  70 #define NAME_IPV6 "IPv6"
  71 #define ADDRLEN_IPV6 128
  72
  73 static int addreq_ipv6(const union addr *a, const union addr *b)
  74   { return !memcmp(a->ipv6.s6_addr, b->ipv6.s6_addr, 16); }
  75
  76 static int match_addrpat_ipv6(const struct addrpat *ap, const union addr *a)
  77 {
  78   unsigned i = 0, m, n = ap->len;
  79
  80   if (!n) return (1);
  81   for (i = 0; n >= 8; i++, n -= 8)
  82     if (ap->addr.ipv6.s6_addr[i] != a->ipv6.s6_addr[i]) return (0);
  83   if (!n) return (1);
  84   m = (MASK8 << (8 - n)) & MASK8;
  85   return (((ap->addr.ipv6.s6_addr[i] ^ a->ipv6.s6_addr[i]) & m) == 0);
  86 }
  87
  88 static void socket_to_sockaddr_ipv6(const struct socket *s,
  89                                     void *sa, size_t *ssz)
  90 {
  91   struct sockaddr_in6 *sin6 = sa;
  92
  93   sin6->sin6_family = AF_INET6;
  94   sin6->sin6_addr = s->addr.ipv6;
  95   sin6->sin6_port = htons(s->port);
  96   sin6->sin6_flowinfo = 0;
  97   sin6->sin6_scope_id = 0;
  98   *ssz = sizeof(*sin6);
  99 }
 100
 101 static void sockaddr_to_addr_ipv6(const void *sa, union addr *a)
 102   { const struct sockaddr_in6 *sin6 = sa; a->ipv6 = sin6->sin6_addr; }
 103
 104 static int init_listen_socket_ipv6(int fd)
 105 {
 106   int yes = 1;
 107
 108   if (setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &yes, sizeof(yes)))
 109     return (-1);
 110   return (0);
 111 }
 112
 113 static const union addr any_ipv6 = { .ipv6 = IN6ADDR_ANY_INIT };
 114
 115 /*----- General utilities -------------------------------------------------*/
 116
 117 /* Answer whether the sockets SA and SB are equal. */
 118 int sockeq(const struct addrops *ao,
 119            const struct socket *sa, const struct socket *sb)
 120   { return (ao->addreq(&sa->addr, &sb->addr) && sa->port == sb->port); }
 121
 122 /* Write a textual description of S to the string D. */
 123 void dputsock(dstr *d, const struct addrops *ao, const struct socket *s)
 124 {
 125   char buf[ADDRLEN];
 126
 127   inet_ntop(ao->af, &s->addr, buf, sizeof(buf));
 128   if (!s->port || ao->af != AF_INET6) dstr_puts(d, buf);
 129   else { dstr_putc(d, '['); dstr_puts(d, buf); dstr_putc(d, ']'); }
 130   if (s->port) dstr_putf(d, ":%d", s->port);
 131 }
 132
 133 /*----- The operations table ----------------------------------------------*/
 134
 135 const struct addrops addroptab[] = {
 136 #define DEFOPS(ty, TY)                                                  \
 137   { ADDRFAM_##TY, NAME_##TY, ADDRLEN_##TY,                              \
 138     &any_##ty, &addrops_sys_##ty,                                       \
 139     addreq_##ty, match_addrpat_##ty,                                    \
 140     socket_to_sockaddr_##ty, sockaddr_to_addr_##ty,                     \
 141     init_listen_socket_##ty },
 142 ADDRTYPES(DEFOPS)
 143   { 0 }
 144 #undef DEFOPS
 145 };
 146
 147 /*----- That's all, folks -------------------------------------------------*/