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 * $FreeBSD$ 34 */ 35 36#include <sys/param.h> 37#include <sys/capsicum.h> 38#include <sys/dnv.h> 39#include <sys/nv.h> 40#include <sys/socket.h> 41#include <sys/sysctl.h> 42 43#include <net/if.h> 44#include <net/if_dl.h> 45 46#include <netinet/in.h> 47#include <netinet6/in6_var.h> 48#include <netinet/icmp6.h> 49#include <netinet6/nd6.h> 50 51#include <arpa/inet.h> 52 53#include <capsicum_helpers.h> 54#include <errno.h> 55#include <stdlib.h> 56#include <string.h> 57#include <syslog.h> 58#include <unistd.h> 59 60#include <libcasper.h> 61#include <libcasper_service.h> 62 63#include "rtsold.h" 64 65static int 66getsocket(int *sockp, int proto) 67{ 68 cap_rights_t rights; 69 int sock; 70 71 if (*sockp >= 0) 72 return (0); 73 74 if ((sock = socket(AF_INET6, SOCK_RAW, proto)) < 0) 75 return (-1); 76 cap_rights_init(&rights, CAP_CONNECT, CAP_SEND); 77 if (caph_rights_limit(sock, &rights) != 0) 78 return (-1); 79 *sockp = sock; 80 81 return (0); 82} 83 84static ssize_t 85sendpacket(int sock, struct sockaddr_in6 *dst, uint32_t ifindex, int hoplimit, 86 const void *data, size_t len) 87{ 88 uint8_t cmsg[CMSG_SPACE(sizeof(struct in6_pktinfo)) + 89 CMSG_SPACE(sizeof(int))]; 90 struct msghdr hdr; 91 struct iovec iov; 92 struct in6_pktinfo *pi; 93 struct cmsghdr *cm; 94 95 memset(&hdr, 0, sizeof(hdr)); 96 hdr.msg_name = dst; 97 hdr.msg_namelen = sizeof(*dst); 98 hdr.msg_iov = &iov; 99 hdr.msg_iovlen = 1; 100 hdr.msg_control = cmsg; 101 hdr.msg_controllen = sizeof(cmsg); 102 103 iov.iov_base = __DECONST(void *, data); 104 iov.iov_len = len; 105 106 /* Specify the outbound interface. */ 107 cm = CMSG_FIRSTHDR(&hdr); 108 cm->cmsg_level = IPPROTO_IPV6; 109 cm->cmsg_type = IPV6_PKTINFO; 110 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); 111 pi = (struct in6_pktinfo *)(void *)CMSG_DATA(cm); 112 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/ 113 pi->ipi6_ifindex = ifindex; 114 115 /* Specify the hop limit of the packet for safety. */ 116 cm = CMSG_NXTHDR(&hdr, cm); 117 cm->cmsg_level = IPPROTO_IPV6; 118 cm->cmsg_type = IPV6_HOPLIMIT; 119 cm->cmsg_len = CMSG_LEN(sizeof(int)); 120 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int)); 121 122 return (sendmsg(sock, &hdr, 0)); 123} 124 125static int 126probe_defrouters(uint32_t ifindex, uint32_t linkid) 127{ 128 static int probesock = -1; 129 struct sockaddr_in6 dst; 130 struct in6_defrouter *p, *ep; 131 char *buf; 132 size_t len; 133 int mib[4]; 134 135 if (ifindex == 0) 136 return (0); 137 if (getsocket(&probesock, IPPROTO_NONE) != 0) 138 return (-1); 139 140 mib[0] = CTL_NET; 141 mib[1] = PF_INET6; 142 mib[2] = IPPROTO_ICMPV6; 143 mib[3] = ICMPV6CTL_ND6_DRLIST; 144 if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) < 0) 145 return (-1); 146 if (len == 0) 147 return (0); 148 149 memset(&dst, 0, sizeof(dst)); 150 dst.sin6_family = AF_INET6; 151 dst.sin6_len = sizeof(dst); 152 153 buf = malloc(len); 154 if (buf == NULL) 155 return (-1); 156 if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) < 0) 157 return (-1); 158 ep = (struct in6_defrouter *)(void *)(buf + len); 159 for (p = (struct in6_defrouter *)(void *)buf; p < ep; p++) { 160 if (ifindex != p->if_index) 161 continue; 162 if (!IN6_IS_ADDR_LINKLOCAL(&p->rtaddr.sin6_addr)) 163 continue; 164 dst.sin6_addr = p->rtaddr.sin6_addr; 165 dst.sin6_scope_id = linkid; 166 (void)sendpacket(probesock, &dst, ifindex, 1, NULL, 0); 167 } 168 free(buf); 169 170 return (0); 171} 172 173static int 174rssend(uint32_t ifindex, uint32_t linkid, const void *data, size_t len) 175{ 176 static int rssock = -1; 177 struct sockaddr_in6 dst; 178 ssize_t n; 179 180 if (getsocket(&rssock, IPPROTO_ICMPV6) != 0) 181 return (-1); 182 183 memset(&dst, 0, sizeof(dst)); 184 dst.sin6_family = AF_INET6; 185 dst.sin6_len = sizeof(dst); 186 dst.sin6_addr = (struct in6_addr)IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; 187 dst.sin6_scope_id = linkid; 188 189 n = sendpacket(rssock, &dst, ifindex, 255, data, len); 190 if (n < 0 || (size_t)n != len) 191 return (-1); 192 return (0); 193} 194 195int 196cap_probe_defrouters(cap_channel_t *cap, struct ifinfo *ifinfo) 197{ 198#ifdef WITH_CASPER 199 nvlist_t *nvl; 200 int error; 201 202 nvl = nvlist_create(0); 203 nvlist_add_string(nvl, "cmd", "probe_defrouters"); 204 nvlist_add_number(nvl, "ifindex", ifinfo->sdl->sdl_index); 205 nvlist_add_number(nvl, "linkid", ifinfo->linkid); 206 207 nvl = cap_xfer_nvlist(cap, nvl); 208 if (nvl == NULL) 209 return (errno); 210 error = (int)dnvlist_get_number(nvl, "error", 0); 211 nvlist_destroy(nvl); 212 errno = error; 213 return (error == 0 ? 0 : -1); 214#else 215 (void)cap; 216 return (probe_defrouters(ifinfo->sdl->sdl_index, ifinfo->linkid)); 217#endif 218} 219 220int 221cap_rssend(cap_channel_t *cap, struct ifinfo *ifinfo) 222{ 223 int error; 224 225#ifdef WITH_CASPER 226 nvlist_t *nvl = nvlist_create(0); 227 nvlist_add_string(nvl, "cmd", "rssend"); 228 nvlist_add_number(nvl, "ifindex", ifinfo->sdl->sdl_index); 229 nvlist_add_number(nvl, "linkid", ifinfo->linkid); 230 nvlist_add_binary(nvl, "data", ifinfo->rs_data, ifinfo->rs_datalen); 231 232 nvl = cap_xfer_nvlist(cap, nvl); 233 if (nvl == NULL) 234 return (errno); 235 error = (int)dnvlist_get_number(nvl, "error", 0); 236 nvlist_destroy(nvl); 237 errno = error; 238#else 239 (void)cap; 240 error = rssend(ifinfo->sdl->sdl_index, ifinfo->linkid, ifinfo->rs_data, 241 ifinfo->rs_datalen); 242#endif 243 244 ifinfo->probes++; 245 if (error != 0 && (errno != ENETDOWN || dflag > 0)) { 246 error = errno; 247 warnmsg(LOG_ERR, __func__, "sendmsg on %s: %s", 248 ifinfo->ifname, strerror(errno)); 249 errno = error; 250 } 251 return (error == 0 ? 0 : -1); 252} 253 254#ifdef WITH_CASPER 255static int 256sendmsg_command(const char *cmd, const nvlist_t *limits __unused, nvlist_t *nvlin, 257 nvlist_t *nvlout __unused) 258{ 259 const void *data; 260 size_t len; 261 uint32_t ifindex, linkid; 262 int error; 263 264 if (strcmp(cmd, "probe_defrouters") != 0 && 265 strcmp(cmd, "rssend") != 0) 266 return (EINVAL); 267 268 ifindex = (uint32_t)nvlist_get_number(nvlin, "ifindex"); 269 linkid = (uint32_t)nvlist_get_number(nvlin, "linkid"); 270 if (strcmp(cmd, "probe_defrouters") == 0) { 271 error = probe_defrouters(ifindex, linkid); 272 } else { 273 data = nvlist_get_binary(nvlin, "data", &len); 274 error = rssend(ifindex, linkid, data, len); 275 } 276 if (error != 0) 277 return (errno); 278 return (0); 279} 280 281CREATE_SERVICE("rtsold.sendmsg", NULL, sendmsg_command, 0); 282#endif /* WITH_CASPER */ 283