1/* $KAME: probe.c,v 1.17 2003/10/05 00:09:36 itojun Exp $ */ 2 3/*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (C) 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include <sys/param.h> 35#include <sys/capsicum.h> 36#include <sys/dnv.h> 37#include <sys/nv.h> 38#include <sys/socket.h> 39#include <sys/sysctl.h> 40 41#include <net/if.h> 42#include <net/if_dl.h> 43 44#include <netinet/in.h> 45#include <netinet6/in6_var.h> 46#include <netinet/icmp6.h> 47#include <netinet6/nd6.h> 48 49#include <arpa/inet.h> 50 51#include <capsicum_helpers.h> 52#include <errno.h> 53#include <stdlib.h> 54#include <string.h> 55#include <syslog.h> 56#include <unistd.h> 57 58#include <libcasper.h> 59#include <libcasper_service.h> 60 61#include "rtsold.h" 62 63static int 64getsocket(int *sockp, int proto) 65{ 66 cap_rights_t rights; 67 int sock; 68 69 if (*sockp >= 0) 70 return (0); 71 72 if ((sock = socket(AF_INET6, SOCK_RAW, proto)) < 0) 73 return (-1); 74 cap_rights_init(&rights, CAP_CONNECT, CAP_SEND); 75 if (caph_rights_limit(sock, &rights) != 0) 76 return (-1); 77 *sockp = sock; 78 79 return (0); 80} 81 82static ssize_t 83sendpacket(int sock, struct sockaddr_in6 *dst, uint32_t ifindex, int hoplimit, 84 const void *data, size_t len) 85{ 86 uint8_t cmsg[CMSG_SPACE(sizeof(struct in6_pktinfo)) + 87 CMSG_SPACE(sizeof(int))]; 88 struct msghdr hdr; 89 struct iovec iov; 90 struct in6_pktinfo *pi; 91 struct cmsghdr *cm; 92 93 memset(&hdr, 0, sizeof(hdr)); 94 hdr.msg_name = dst; 95 hdr.msg_namelen = sizeof(*dst); 96 hdr.msg_iov = &iov; 97 hdr.msg_iovlen = 1; 98 hdr.msg_control = cmsg; 99 hdr.msg_controllen = sizeof(cmsg); 100 101 iov.iov_base = __DECONST(void *, data); 102 iov.iov_len = len; 103 104 /* Specify the outbound interface. */ 105 cm = CMSG_FIRSTHDR(&hdr); 106 cm->cmsg_level = IPPROTO_IPV6; 107 cm->cmsg_type = IPV6_PKTINFO; 108 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 109 pi = (struct in6_pktinfo *)(void *)CMSG_DATA(cm); 110 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 111 pi->ipi6_ifindex = ifindex; 112 113 /* Specify the hop limit of the packet for safety. */ 114 cm = CMSG_NXTHDR(&hdr, cm); 115 cm->cmsg_level = IPPROTO_IPV6; 116 cm->cmsg_type = IPV6_HOPLIMIT; 117 cm->cmsg_len = CMSG_LEN(sizeof(int)); 118 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 119 120 return (sendmsg(sock, &hdr, 0)); 121} 122 123static int 124probe_defrouters(uint32_t ifindex, uint32_t linkid) 125{ 126 static int probesock = -1; 127 struct sockaddr_in6 dst; 128 struct in6_defrouter *p, *ep; 129 char *buf; 130 size_t len; 131 int mib[4]; 132 133 if (ifindex == 0) 134 return (0); 135 if (getsocket(&probesock, IPPROTO_NONE) != 0) 136 return (-1); 137 138 mib[0] = CTL_NET; 139 mib[1] = PF_INET6; 140 mib[2] = IPPROTO_ICMPV6; 141 mib[3] = ICMPV6CTL_ND6_DRLIST; 142 if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) < 0) 143 return (-1); 144 if (len == 0) 145 return (0); 146 147 memset(&dst, 0, sizeof(dst)); 148 dst.sin6_family = AF_INET6; 149 dst.sin6_len = sizeof(dst); 150 151 buf = malloc(len); 152 if (buf == NULL) 153 return (-1); 154 if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) < 0) 155 return (-1); 156 ep = (struct in6_defrouter *)(void *)(buf + len); 157 for (p = (struct in6_defrouter *)(void *)buf; p < ep; p++) { 158 if (ifindex != p->if_index) 159 continue; 160 if (!IN6_IS_ADDR_LINKLOCAL(&p->rtaddr.sin6_addr)) 161 continue; 162 dst.sin6_addr = p->rtaddr.sin6_addr; 163 dst.sin6_scope_id = linkid; 164 (void)sendpacket(probesock, &dst, ifindex, 1, NULL, 0); 165 } 166 free(buf); 167 168 return (0); 169} 170 171static int 172rssend(uint32_t ifindex, uint32_t linkid, const void *data, size_t len) 173{ 174 static int rssock = -1; 175 struct sockaddr_in6 dst; 176 ssize_t n; 177 178 if (getsocket(&rssock, IPPROTO_ICMPV6) != 0) 179 return (-1); 180 181 memset(&dst, 0, sizeof(dst)); 182 dst.sin6_family = AF_INET6; 183 dst.sin6_len = sizeof(dst); 184 dst.sin6_addr = (struct in6_addr)IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; 185 dst.sin6_scope_id = linkid; 186 187 n = sendpacket(rssock, &dst, ifindex, 255, data, len); 188 if (n < 0 || (size_t)n != len) 189 return (-1); 190 return (0); 191} 192 193int 194cap_probe_defrouters(cap_channel_t *cap, struct ifinfo *ifinfo) 195{ 196#ifdef WITH_CASPER 197 nvlist_t *nvl; 198 int error; 199 200 nvl = nvlist_create(0); 201 nvlist_add_string(nvl, "cmd", "probe_defrouters"); 202 nvlist_add_number(nvl, "ifindex", ifinfo->sdl->sdl_index); 203 nvlist_add_number(nvl, "linkid", ifinfo->linkid); 204 205 nvl = cap_xfer_nvlist(cap, nvl); 206 if (nvl == NULL) 207 return (errno); 208 error = (int)dnvlist_get_number(nvl, "error", 0); 209 nvlist_destroy(nvl); 210 errno = error; 211 return (error == 0 ? 0 : -1); 212#else 213 (void)cap; 214 return (probe_defrouters(ifinfo->sdl->sdl_index, ifinfo->linkid)); 215#endif 216} 217 218int 219cap_rssend(cap_channel_t *cap, struct ifinfo *ifinfo) 220{ 221 int error; 222 223#ifdef WITH_CASPER 224 nvlist_t *nvl = nvlist_create(0); 225 nvlist_add_string(nvl, "cmd", "rssend"); 226 nvlist_add_number(nvl, "ifindex", ifinfo->sdl->sdl_index); 227 nvlist_add_number(nvl, "linkid", ifinfo->linkid); 228 nvlist_add_binary(nvl, "data", ifinfo->rs_data, ifinfo->rs_datalen); 229 230 nvl = cap_xfer_nvlist(cap, nvl); 231 if (nvl == NULL) 232 return (errno); 233 error = (int)dnvlist_get_number(nvl, "error", 0); 234 nvlist_destroy(nvl); 235 errno = error; 236#else 237 (void)cap; 238 error = rssend(ifinfo->sdl->sdl_index, ifinfo->linkid, ifinfo->rs_data, 239 ifinfo->rs_datalen); 240#endif 241 242 ifinfo->probes++; 243 if (error != 0 && (errno != ENETDOWN || dflag > 0)) { 244 error = errno; 245 warnmsg(LOG_ERR, __func__, "sendmsg on %s: %s", 246 ifinfo->ifname, strerror(errno)); 247 errno = error; 248 } 249 return (error == 0 ? 0 : -1); 250} 251 252#ifdef WITH_CASPER 253static int 254sendmsg_command(const char *cmd, const nvlist_t *limits __unused, nvlist_t *nvlin, 255 nvlist_t *nvlout __unused) 256{ 257 const void *data; 258 size_t len; 259 uint32_t ifindex, linkid; 260 int error; 261 262 if (strcmp(cmd, "probe_defrouters") != 0 && 263 strcmp(cmd, "rssend") != 0) 264 return (EINVAL); 265 266 ifindex = (uint32_t)nvlist_get_number(nvlin, "ifindex"); 267 linkid = (uint32_t)nvlist_get_number(nvlin, "linkid"); 268 if (strcmp(cmd, "probe_defrouters") == 0) { 269 error = probe_defrouters(ifindex, linkid); 270 } else { 271 data = nvlist_get_binary(nvlin, "data", &len); 272 error = rssend(ifindex, linkid, data, len); 273 } 274 if (error != 0) 275 return (errno); 276 return (0); 277} 278 279CREATE_SERVICE("rtsold.sendmsg", NULL, sendmsg_command, 0); 280#endif /* WITH_CASPER */ 281