code.delx.au - pulseaudio/blob - src/pulsecore/ipacl.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   Copyright 2004-2006 Lennart Poettering
   7   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   8
   9   PulseAudio is free software; you can redistribute it and/or modify
  10   it under the terms of the GNU Lesser General Public License as
  11   published by the Free Software Foundation; either version 2.1 of the
  12   License, or (at your option) any later version.
  13
  14   PulseAudio is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public
  20   License along with PulseAudio; if not, write to the Free Software
  21   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  22   USA.
  23 ***/
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include <config.h>
  27 #endif
  28
  29 #include <sys/types.h>
  30 #include <sys/types.h>
  31 #include <string.h>
  32
  33 #ifdef HAVE_SYS_SOCKET_H
  34 #include <sys/socket.h>
  35 #endif
  36 #ifdef HAVE_NETINET_IN_H
  37 #include <netinet/in.h>
  38 #endif
  39 #ifdef HAVE_NETINET_IN_SYSTM_H
  40 #include <netinet/in_systm.h>
  41 #endif
  42 #ifdef HAVE_NETINET_IP_H
  43 #include <netinet/ip.h>
  44 #endif
  45 #ifdef HAVE_ARPA_INET_H
  46 #include <arpa/inet.h>
  47 #endif
  48
  49 #include "winsock.h"
  50
  51 #include <pulse/xmalloc.h>
  52
  53 #include <pulsecore/core-util.h>
  54 #include <pulsecore/llist.h>
  55 #include <pulsecore/log.h>
  56
  57 #ifndef HAVE_INET_PTON
  58 #include "inet_pton.h"
  59 #endif
  60
  61 #include "ipacl.h"
  62
  63 struct acl_entry {
  64     PA_LLIST_FIELDS(struct acl_entry);
  65     int family;
  66     struct in_addr address_ipv4;
  67     struct in6_addr address_ipv6;
  68     int bits;
  69 };
  70
  71 struct pa_ip_acl {
  72     PA_LLIST_HEAD(struct acl_entry, entries);
  73 };
  74
  75 pa_ip_acl* pa_ip_acl_new(const char *s) {
  76     const char *state = NULL;
  77     char *a;
  78     pa_ip_acl *acl;
  79
  80     assert(s);
  81
  82     acl = pa_xnew(pa_ip_acl, 1);
  83     PA_LLIST_HEAD_INIT(struct acl_entry, acl->entries);
  84
  85     while ((a = pa_split(s, ";", &state))) {
  86         char *slash;
  87         struct acl_entry e, *n;
  88         uint32_t bits;
  89
  90         if ((slash = strchr(a, '/'))) {
  91             *slash = 0;
  92             slash++;
  93             if (pa_atou(slash, &bits) < 0) {
  94                 pa_log("failed to parse number of bits: %s", slash);
  95                 goto fail;
  96             }
  97         } else
  98             bits = (uint32_t) -1;
  99
 100         if (inet_pton(AF_INET, a, &e.address_ipv4) > 0) {
 101
 102             e.bits = bits == (uint32_t) -1 ? 32 : (int) bits;
 103
 104             if (e.bits > 32) {
 105                 pa_log("number of bits out of range: %i", e.bits);
 106                 goto fail;
 107             }
 108
 109             e.family = AF_INET;
 110
 111             if (e.bits < 32 && (uint32_t) (ntohl(e.address_ipv4.s_addr) << e.bits) != 0)
 112                 pa_log_warn("WARNING: Host part of ACL entry '%s/%u' is not zero!", a, e.bits);
 113
 114         } else if (inet_pton(AF_INET6, a, &e.address_ipv6) > 0) {
 115
 116             e.bits = bits == (uint32_t) -1 ? 128 : (int) bits;
 117
 118             if (e.bits > 128) {
 119                 pa_log("number of bits out of range: %i", e.bits);
 120                 goto fail;
 121             }
 122             e.family = AF_INET6;
 123
 124             if (e.bits < 128) {
 125                 int t = 0, i;
 126
 127                 for (i = 0, bits = e.bits; i < 16; i++) {
 128
 129                     if (bits >= 8)
 130                         bits -= 8;
 131                     else {
 132                         if ((uint8_t) ((e.address_ipv6.s6_addr[i]) << bits) != 0) {
 133                             t = 1;
 134                             break;
 135                         }
 136                         bits = 0;
 137                     }
 138                 }
 139
 140                 if (t)
 141                     pa_log_warn("WARNING: Host part of ACL entry '%s/%u' is not zero!", a, e.bits);
 142             }
 143
 144         } else {
 145             pa_log("failed to parse address: %s", a);
 146             goto fail;
 147         }
 148
 149         n = pa_xmemdup(&e, sizeof(struct acl_entry));
 150         PA_LLIST_PREPEND(struct acl_entry, acl->entries, n);
 151
 152         pa_xfree(a);
 153     }
 154
 155     return acl;
 156
 157 fail:
 158     pa_xfree(a);
 159     pa_ip_acl_free(acl);
 160
 161     return NULL;
 162 }
 163
 164 void pa_ip_acl_free(pa_ip_acl *acl) {
 165     assert(acl);
 166
 167     while (acl->entries) {
 168         struct acl_entry *e = acl->entries;
 169         PA_LLIST_REMOVE(struct acl_entry, acl->entries, e);
 170         pa_xfree(e);
 171     }
 172
 173     pa_xfree(acl);
 174 }
 175
 176 int pa_ip_acl_check(pa_ip_acl *acl, int fd) {
 177     struct sockaddr_storage sa;
 178     struct acl_entry *e;
 179     socklen_t  salen;
 180
 181     assert(acl);
 182     assert(fd >= 0);
 183
 184     salen = sizeof(sa);
 185     if (getpeername(fd, (struct sockaddr*) &sa, &salen) < 0)
 186         return -1;
 187
 188     if (sa.ss_family != AF_INET && sa.ss_family != AF_INET6)
 189         return -1;
 190
 191     if (sa.ss_family == AF_INET && salen != sizeof(struct sockaddr_in))
 192         return -1;
 193
 194     if (sa.ss_family == AF_INET6 && salen != sizeof(struct sockaddr_in6))
 195         return -1;
 196
 197     for (e = acl->entries; e; e = e->next) {
 198
 199         if (e->family != sa.ss_family)
 200             continue;
 201
 202         if (e->family == AF_INET) {
 203             struct sockaddr_in *sai = (struct sockaddr_in*) &sa;
 204
 205             if (e->bits == 0 || /* this needs special handling because >> takes the right-hand side modulo 32 */
 206                 (ntohl(sai->sin_addr.s_addr ^ e->address_ipv4.s_addr) >> (32 - e->bits)) == 0)
 207                 return 1;
 208         } else if (e->family == AF_INET6) {
 209             int i, bits ;
 210             struct sockaddr_in6 *sai = (struct sockaddr_in6*) &sa;
 211
 212             if (e->bits == 128)
 213                 return memcmp(&sai->sin6_addr, &e->address_ipv6, 16) == 0;
 214
 215             if (e->bits == 0)
 216                 return 1;
 217
 218             for (i = 0, bits = e->bits; i < 16; i++) {
 219
 220                 if (bits >= 8) {
 221                     if (sai->sin6_addr.s6_addr[i] != e->address_ipv6.s6_addr[i])
 222                         break;
 223
 224                     bits -= 8;
 225                 } else {
 226                     if ((sai->sin6_addr.s6_addr[i] ^ e->address_ipv6.s6_addr[i]) >> (8 - bits) != 0)
 227                         break;
 228
 229                     bits = 0;
 230                 }
 231
 232                 if (bits == 0)
 233                     return 1;
 234             }
 235         }
 236     }
 237
 238     return 0;
 239 }