sbin/ifconfig/util.c

   1 /*      $NetBSD: util.c,v 1.12 2009/08/07 18:53:37 dyoung Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2008 David Young.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 #ifndef lint
  30 __RCSID("$NetBSD: util.c,v 1.12 2009/08/07 18:53:37 dyoung Exp $");
  31 #endif /* not lint */
  32
  33 #include <ctype.h>
  34 #include <err.h>
  35 #include <errno.h>
  36 #include <netdb.h>
  37 #include <stddef.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <unistd.h>
  42 #include <util.h>
  43
  44 #include <sys/param.h>
  45 #include <sys/types.h>
  46 #include <sys/socket.h>
  47 #include <ifaddrs.h>
  48
  49 #include <sys/ioctl.h>
  50 #include <net/if.h>
  51 #include <net/if_dl.h>
  52 #include <netinet/in.h>         /* XXX */
  53
  54 #include "env.h"
  55 #include "extern.h"
  56 #include "util.h"
  57
  58 int
  59 getsock(int naf)
  60 {
  61         static int oaf = -1, s;
  62
  63         if (oaf == naf || (oaf != -1 && naf == AF_UNSPEC))
  64                 return s;
  65
  66         if (oaf != -1)
  67                 close(s);
  68
  69         if (naf == AF_UNSPEC)
  70                 naf = AF_INET;
  71
  72         s = socket(naf, SOCK_DGRAM, 0);
  73         if (s == -1)
  74                 oaf = -1;
  75         else
  76                 oaf = naf;
  77         return s;
  78 }
  79
  80 const char *
  81 get_string(const char *val, const char *sep, u_int8_t *buf, int *lenp)
  82 {
  83         int len;
  84         bool hexstr;
  85         u_int8_t *p;
  86
  87         len = *lenp;
  88         p = buf;
  89         hexstr = (val[0] == '0' && tolower((u_char)val[1]) == 'x');
  90         if (hexstr)
  91                 val += 2;
  92         for (;;) {
  93                 if (*val == '\0')
  94                         break;
  95                 if (sep != NULL && strchr(sep, *val) != NULL) {
  96                         val++;
  97                         break;
  98                 }
  99                 if (hexstr) {
 100                         if (!isxdigit((u_char)val[0]) ||
 101                             !isxdigit((u_char)val[1])) {
 102                                 warnx("bad hexadecimal digits");
 103                                 return NULL;
 104                         }
 105                 }
 106                 if (p > buf + len) {
 107                         if (hexstr)
 108                                 warnx("hexadecimal digits too long");
 109                         else
 110                                 warnx("strings too long");
 111                         return NULL;
 112                 }
 113                 if (hexstr) {
 114 #define tohex(x)        (isdigit(x) ? (x) - '0' : tolower(x) - 'a' + 10)
 115                         *p++ = (tohex((u_char)val[0]) << 4) |
 116                             tohex((u_char)val[1]);
 117 #undef tohex
 118                         val += 2;
 119                 } else
 120                         *p++ = *val++;
 121         }
 122         len = p - buf;
 123         if (len < *lenp)
 124                 memset(p, 0, *lenp - len);
 125         *lenp = len;
 126         return val;
 127 }
 128
 129 void
 130 print_string(const u_int8_t *buf, int len)
 131 {
 132         int i;
 133         bool hasspc;
 134
 135         i = 0;
 136         hasspc = false;
 137         if (len < 2 || buf[0] != '0' || tolower(buf[1]) != 'x') {
 138                 for (; i < len; i++) {
 139                         if (!isprint(buf[i]))
 140                                 break;
 141                         if (isspace(buf[i]))
 142                                 hasspc = true;
 143                 }
 144         }
 145         if (i == len) {
 146                 if (hasspc || len == 0)
 147                         printf("\"%.*s\"", len, buf);
 148                 else
 149                         printf("%.*s", len, buf);
 150         } else {
 151                 printf("0x");
 152                 for (i = 0; i < len; i++)
 153                         printf("%02x", buf[i]);
 154         }
 155 }
 156
 157 struct paddr_prefix *
 158 prefixlen_to_mask(int af, int plen)
 159 {
 160         union {
 161                 struct sockaddr sa;
 162                 struct sockaddr_in sin;
 163                 struct sockaddr_in6 sin6;
 164         } u;
 165         struct paddr_prefix *pfx;
 166         size_t addrlen;
 167         uint8_t *addr;
 168         int nbit;
 169
 170         memset(&u, 0, sizeof(u));
 171
 172         switch (af) {
 173         case AF_INET:
 174                 addrlen = sizeof(u.sin.sin_addr);
 175                 addr = (uint8_t *)&u.sin.sin_addr;
 176                 u.sa.sa_len = sizeof(u.sin);
 177                 break;
 178         case AF_INET6:
 179                 addrlen = sizeof(u.sin6.sin6_addr);
 180                 addr = (uint8_t *)&u.sin6.sin6_addr;
 181                 u.sa.sa_len = sizeof(u.sin6);
 182                 break;
 183         default:
 184                 errno = EINVAL;
 185                 return NULL;
 186         }
 187         u.sa.sa_family = af;
 188
 189         if (plen < 0 || (size_t)plen > addrlen * NBBY) {
 190                 errno = EINVAL;
 191                 return NULL;
 192         }
 193
 194         if (plen == 0)
 195                 plen = addrlen * NBBY;
 196
 197         memset(addr, 0xff, (plen + NBBY - 1) / NBBY);
 198
 199         nbit = plen % NBBY;
 200         if (nbit != 0)
 201                 addr[plen / NBBY] &= ~((uint8_t)0xff >> nbit);
 202         pfx = malloc(offsetof(struct paddr_prefix, pfx_addr) + u.sa.sa_len);
 203         if (pfx == NULL)
 204                 return NULL;
 205         pfx->pfx_len = plen;
 206         memcpy(&pfx->pfx_addr, &u.sa, u.sa.sa_len);
 207
 208         return pfx;
 209 }
 210
 211 int
 212 direct_ioctl(prop_dictionary_t env, unsigned long cmd, void *data)
 213 {
 214         const char *ifname;
 215         int s;
 216
 217         if ((s = getsock(AF_UNSPEC)) == -1)
 218                 err(EXIT_FAILURE, "getsock");
 219
 220         if ((ifname = getifname(env)) == NULL)
 221                 err(EXIT_FAILURE, "getifname");
 222
 223         estrlcpy(data, ifname, IFNAMSIZ);
 224
 225         return ioctl(s, cmd, data);
 226 }
 227
 228 int
 229 indirect_ioctl(prop_dictionary_t env, unsigned long cmd, void *data)
 230 {
 231         struct ifreq ifr;
 232
 233         memset(&ifr, 0, sizeof(ifr));
 234
 235         ifr.ifr_data = data;
 236
 237         return direct_ioctl(env, cmd, &ifr);
 238 }
 239
 240 void
 241 print_link_addresses(prop_dictionary_t env, bool print_active_only)
 242 {
 243         char hbuf[NI_MAXHOST];
 244         const char *ifname;
 245         int s;
 246         struct ifaddrs *ifa, *ifap;
 247         const struct sockaddr_dl *sdl;
 248         struct if_laddrreq iflr;
 249
 250         if ((ifname = getifname(env)) == NULL)
 251                 err(EXIT_FAILURE, "%s: getifname", __func__);
 252
 253         if ((s = getsock(AF_LINK)) == -1)
 254                 err(EXIT_FAILURE, "%s: getsock", __func__);
 255
 256         if (getifaddrs(&ifap) == -1)
 257                 err(EXIT_FAILURE, "%s: getifaddrs", __func__);
 258
 259         memset(&iflr, 0, sizeof(iflr));
 260
 261         strlcpy(iflr.iflr_name, ifname, sizeof(iflr.iflr_name));
 262
 263         for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
 264                 if (strcmp(ifname, ifa->ifa_name) != 0)
 265                         continue;
 266                 if (ifa->ifa_addr->sa_family != AF_LINK)
 267                         continue;
 268
 269                 sdl = satocsdl(ifa->ifa_addr);
 270
 271                 memcpy(&iflr.addr, ifa->ifa_addr, MIN(ifa->ifa_addr->sa_len,
 272                     sizeof(iflr.addr)));
 273                 iflr.flags = IFLR_PREFIX;
 274                 iflr.prefixlen = sdl->sdl_alen * NBBY;
 275
 276                 if (ioctl(s, SIOCGLIFADDR, &iflr) == -1)
 277                         err(EXIT_FAILURE, "%s: ioctl", __func__);
 278
 279                 if (((iflr.flags & IFLR_ACTIVE) != 0) != print_active_only)
 280                         continue;
 281
 282                 if (getnameinfo(ifa->ifa_addr, ifa->ifa_addr->sa_len,
 283                         hbuf, sizeof(hbuf), NULL, 0,
 284                         Nflag ? 0 : NI_NUMERICHOST) == 0 &&
 285                     hbuf[0] != '\0') {
 286                         printf("\t%s %s\n",
 287                             print_active_only ? "address:" : "link", hbuf);
 288                 }
 289         }
 290         freeifaddrs(ifap);
 291 }
 292
 293 int16_t
 294 ifa_get_preference(const char *ifname, const struct sockaddr *sa)
 295 {
 296         struct if_addrprefreq ifap;
 297         int s;
 298
 299         if ((s = getsock(sa->sa_family)) == -1) {
 300                 if (errno == EPROTONOSUPPORT)
 301                         return 0;
 302                 err(EXIT_FAILURE, "socket");
 303         }
 304         memset(&ifap, 0, sizeof(ifap));
 305         estrlcpy(ifap.ifap_name, ifname, sizeof(ifap.ifap_name));
 306         memcpy(&ifap.ifap_addr, sa, MIN(sizeof(ifap.ifap_addr), sa->sa_len));
 307         if (ioctl(s, SIOCGIFADDRPREF, &ifap) == -1) {
 308                 if (errno == EADDRNOTAVAIL || errno == EAFNOSUPPORT)
 309                         return 0;
 310                 warn("SIOCGIFADDRPREF");
 311         }
 312         return ifap.ifap_preference;
 313 }
 314
 315 void
 316 ifa_print_preference(const char *ifname, const struct sockaddr *sa)
 317 {
 318         int16_t preference;
 319
 320         if (lflag)
 321                 return;
 322
 323         preference = ifa_get_preference(ifname, sa);
 324         printf(" preference %" PRId16, preference);
 325 }
 326
 327 bool
 328 ifa_any_preferences(const char *ifname, struct ifaddrs *ifap, int family)
 329 {
 330         struct ifaddrs *ifa;
 331
 332         /* Print address preference numbers if any address has a non-zero
 333          * preference assigned.
 334          */
 335         for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
 336                 if (strcmp(ifname, ifa->ifa_name) != 0)
 337                         continue;
 338                 if (ifa->ifa_addr->sa_family != family)
 339                         continue;
 340                 if (ifa_get_preference(ifa->ifa_name, ifa->ifa_addr) != 0)
 341                         return true;
 342         }
 343         return false;
 344 }
 345
 346
 347 #ifdef INET6
 348 /* KAME idiosyncrasy */
 349 void
 350 in6_fillscopeid(struct sockaddr_in6 *sin6)
 351 {
 352         if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
 353                 sin6->sin6_scope_id =
 354                         ntohs(*(u_int16_t *)&sin6->sin6_addr.s6_addr[2]);
 355                 sin6->sin6_addr.s6_addr[2] = sin6->sin6_addr.s6_addr[3] = 0;
 356         }
 357 }
 358 #endif /* INET6 */