1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 "namespace.h" 30 #include <sys/param.h> 31 #include <sys/sysctl.h> 32 #include <sys/ioctl.h> 33 #include <sys/socket.h> 34 #include <net/if.h> 35 #include <net/if_dl.h> 36 #include <net/route.h> 37 38 #include <errno.h> 39 #include <ifaddrs.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include "un-namespace.h" 43 44 #define SALIGN (sizeof(long) - 1) 45 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : \ 46 (SALIGN + 1)) 47 #define MAX_SYSCTL_TRY 5 48 #define RTA_MASKS (RTA_GATEWAY | RTA_IFP | RTA_IFA) 49 50 int 51 getifmaddrs(struct ifmaddrs **pif) 52 { 53 int icnt = 1; 54 int dcnt = 0; 55 int ntry = 0; 56 size_t len; 57 size_t needed; 58 int mib[6]; 59 int i; 60 char *buf; 61 char *data; 62 char *next; 63 char *p; 64 struct ifma_msghdr *ifmam; 65 struct ifmaddrs *ifa, *ift; 66 struct rt_msghdr *rtm; 67 struct sockaddr *sa; 68 69 mib[0] = CTL_NET; 70 mib[1] = PF_ROUTE; 71 mib[2] = 0; /* protocol */ 72 mib[3] = 0; /* wildcard address family */ 73 mib[4] = NET_RT_IFMALIST; 74 mib[5] = 0; /* no flags */ 75 do { 76 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 77 return (-1); 78 if ((buf = malloc(needed)) == NULL) 79 return (-1); 80 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) { 81 if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) { 82 free(buf); 83 return (-1); 84 } 85 free(buf); 86 buf = NULL; 87 } 88 } while (buf == NULL); 89 90 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 91 rtm = (struct rt_msghdr *)(void *)next; 92 if (rtm->rtm_version != RTM_VERSION) 93 continue; 94 switch (rtm->rtm_type) { 95 case RTM_NEWMADDR: 96 ifmam = (struct ifma_msghdr *)(void *)rtm; 97 if ((ifmam->ifmam_addrs & RTA_IFA) == 0) 98 break; 99 icnt++; 100 p = (char *)(ifmam + 1); 101 for (i = 0; i < RTAX_MAX; i++) { 102 if ((RTA_MASKS & ifmam->ifmam_addrs & 103 (1 << i)) == 0) 104 continue; 105 sa = (struct sockaddr *)(void *)p; 106 len = SA_RLEN(sa); 107 dcnt += len; 108 p += len; 109 } 110 break; 111 } 112 } 113 114 data = malloc(sizeof(struct ifmaddrs) * icnt + dcnt); 115 if (data == NULL) { 116 free(buf); 117 return (-1); 118 } 119 120 ifa = (struct ifmaddrs *)(void *)data; 121 data += sizeof(struct ifmaddrs) * icnt; 122 123 memset(ifa, 0, sizeof(struct ifmaddrs) * icnt); 124 ift = ifa; 125 126 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) { 127 rtm = (struct rt_msghdr *)(void *)next; 128 if (rtm->rtm_version != RTM_VERSION) 129 continue; 130 131 switch (rtm->rtm_type) { 132 case RTM_NEWMADDR: 133 ifmam = (struct ifma_msghdr *)(void *)rtm; 134 if ((ifmam->ifmam_addrs & RTA_IFA) == 0) 135 break; 136 137 p = (char *)(ifmam + 1); 138 for (i = 0; i < RTAX_MAX; i++) { 139 if ((RTA_MASKS & ifmam->ifmam_addrs & 140 (1 << i)) == 0) 141 continue; 142 sa = (struct sockaddr *)(void *)p; 143 len = SA_RLEN(sa); 144 switch (i) { 145 case RTAX_GATEWAY: 146 ift->ifma_lladdr = 147 (struct sockaddr *)(void *)data; 148 memcpy(data, p, len); 149 data += len; 150 break; 151 152 case RTAX_IFP: 153 ift->ifma_name = 154 (struct sockaddr *)(void *)data; 155 memcpy(data, p, len); 156 data += len; 157 break; 158 159 case RTAX_IFA: 160 ift->ifma_addr = 161 (struct sockaddr *)(void *)data; 162 memcpy(data, p, len); 163 data += len; 164 break; 165 166 default: 167 data += len; 168 break; 169 } 170 p += len; 171 } 172 ift->ifma_next = ift + 1; 173 ift = ift->ifma_next; 174 break; 175 } 176 } 177 178 free(buf); 179 180 if (ift > ifa) { 181 ift--; 182 ift->ifma_next = NULL; 183 *pif = ifa; 184 } else { 185 *pif = NULL; 186 free(ifa); 187 } 188 return (0); 189 } 190 191 void 192 freeifmaddrs(struct ifmaddrs *ifmp) 193 { 194 195 free(ifmp); 196 } 197