1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2003 Bruce M. Simpson. 5 * All rights reserved 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "namespace.h" 33 #include <sys/param.h> 34 #include <sys/sysctl.h> 35 #include <sys/ioctl.h> 36 #include <sys/socket.h> 37 #include <net/if.h> 38 #include <net/if_dl.h> 39 #include <net/route.h> 40 41 #include <errno.h> 42 #include <ifaddrs.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include "un-namespace.h" 46 47 #define SALIGN (sizeof(long) - 1) 48 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : \ 49 (SALIGN + 1)) 50 #define MAX_SYSCTL_TRY 5 51 #define RTA_MASKS (RTA_GATEWAY | RTA_IFP | RTA_IFA) 52 53 int 54 getifmaddrs(struct ifmaddrs **pif) 55 { 56 int icnt = 1; 57 int dcnt = 0; 58 int ntry = 0; 59 size_t len; 60 size_t needed; 61 int mib[6]; 62 int i; 63 char *buf; 64 char *data; 65 char *next; 66 char *p; 67 struct ifma_msghdr *ifmam; 68 struct ifmaddrs *ifa, *ift; 69 struct rt_msghdr *rtm; 70 struct sockaddr *sa; 71 72 mib[0] = CTL_NET; 73 mib[1] = PF_ROUTE; 74 mib[2] = 0; /* protocol */ 75 mib[3] = 0; /* wildcard address family */ 76 mib[4] = NET_RT_IFMALIST; 77 mib[5] = 0; /* no flags */ 78 do { 79 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 80 return (-1); 81 if ((buf = malloc(needed)) == NULL) 82 return (-1); 83 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) { 84 if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) { 85 free(buf); 86 return (-1); 87 } 88 free(buf); 89 buf = NULL; 90 } 91 } while (buf == NULL); 92 93 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 94 rtm = (struct rt_msghdr *)(void *)next; 95 if (rtm->rtm_version != RTM_VERSION) 96 continue; 97 switch (rtm->rtm_type) { 98 case RTM_NEWMADDR: 99 ifmam = (struct ifma_msghdr *)(void *)rtm; 100 if ((ifmam->ifmam_addrs & RTA_IFA) == 0) 101 break; 102 icnt++; 103 p = (char *)(ifmam + 1); 104 for (i = 0; i < RTAX_MAX; i++) { 105 if ((RTA_MASKS & ifmam->ifmam_addrs & 106 (1 << i)) == 0) 107 continue; 108 sa = (struct sockaddr *)(void *)p; 109 len = SA_RLEN(sa); 110 dcnt += len; 111 p += len; 112 } 113 break; 114 } 115 } 116 117 data = malloc(sizeof(struct ifmaddrs) * icnt + dcnt); 118 if (data == NULL) { 119 free(buf); 120 return (-1); 121 } 122 123 ifa = (struct ifmaddrs *)(void *)data; 124 data += sizeof(struct ifmaddrs) * icnt; 125 126 memset(ifa, 0, sizeof(struct ifmaddrs) * icnt); 127 ift = ifa; 128 129 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 130 rtm = (struct rt_msghdr *)(void *)next; 131 if (rtm->rtm_version != RTM_VERSION) 132 continue; 133 134 switch (rtm->rtm_type) { 135 case RTM_NEWMADDR: 136 ifmam = (struct ifma_msghdr *)(void *)rtm; 137 if ((ifmam->ifmam_addrs & RTA_IFA) == 0) 138 break; 139 140 p = (char *)(ifmam + 1); 141 for (i = 0; i < RTAX_MAX; i++) { 142 if ((RTA_MASKS & ifmam->ifmam_addrs & 143 (1 << i)) == 0) 144 continue; 145 sa = (struct sockaddr *)(void *)p; 146 len = SA_RLEN(sa); 147 switch (i) { 148 case RTAX_GATEWAY: 149 ift->ifma_lladdr = 150 (struct sockaddr *)(void *)data; 151 memcpy(data, p, len); 152 data += len; 153 break; 154 155 case RTAX_IFP: 156 ift->ifma_name = 157 (struct sockaddr *)(void *)data; 158 memcpy(data, p, len); 159 data += len; 160 break; 161 162 case RTAX_IFA: 163 ift->ifma_addr = 164 (struct sockaddr *)(void *)data; 165 memcpy(data, p, len); 166 data += len; 167 break; 168 169 default: 170 data += len; 171 break; 172 } 173 p += len; 174 } 175 ift->ifma_next = ift + 1; 176 ift = ift->ifma_next; 177 break; 178 } 179 } 180 181 free(buf); 182 183 if (ift > ifa) { 184 ift--; 185 ift->ifma_next = NULL; 186 *pif = ifa; 187 } else { 188 *pif = NULL; 189 free(ifa); 190 } 191 return (0); 192 } 193 194 void 195 freeifmaddrs(struct ifmaddrs *ifmp) 196 { 197 198 free(ifmp); 199 } 200