ip/ipmaddr.c

   1 /*
   2  * ipmaddr.c            "ip maddress".
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <syslog.h>
  17 #include <fcntl.h>
  18 #include <sys/ioctl.h>
  19 #include <sys/socket.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/if.h>
  22 #include <linux/if_arp.h>
  23 #include <linux/sockios.h>
  24 #include <netinet/in.h>
  25 #include <arpa/inet.h>
  26 #include <string.h>
  27
  28 #include "rt_names.h"
  29 #include "utils.h"
  30
  31 static struct {
  32         char *dev;
  33         int  family;
  34 } filter;
  35
  36 static void usage(void) __attribute__((noreturn));
  37
  38 static void usage(void)
  39 {
  40         fprintf(stderr, "Usage: ip maddr [ add | del ] MULTIADDR dev STRING\n");
  41         fprintf(stderr, "       ip maddr show [ dev STRING ]\n");
  42         exit(-1);
  43 }
  44
  45 static int parse_hex(char *str, unsigned char *addr)
  46 {
  47         int len=0;
  48
  49         while (*str) {
  50                 int tmp;
  51                 if (str[1] == 0)
  52                         return -1;
  53                 if (sscanf(str, "%02x", &tmp) != 1)
  54                         return -1;
  55                 addr[len] = tmp;
  56                 len++;
  57                 str += 2;
  58         }
  59         return len;
  60 }
  61
  62 struct ma_info
  63 {
  64         struct ma_info *next;
  65         int             index;
  66         int             users;
  67         char            *features;
  68         char            name[IFNAMSIZ];
  69         inet_prefix     addr;
  70 };
  71
  72 void maddr_ins(struct ma_info **lst, struct ma_info *m)
  73 {
  74         struct ma_info *mp;
  75
  76         for (; (mp=*lst) != NULL; lst = &mp->next) {
  77                 if (mp->index > m->index)
  78                         break;
  79         }
  80         m->next = *lst;
  81         *lst = m;
  82 }
  83
  84 void read_dev_mcast(struct ma_info **result_p)
  85 {
  86         char buf[256];
  87         FILE *fp = fopen("/proc/net/dev_mcast", "r");
  88
  89         if (!fp)
  90                 return;
  91
  92         while (fgets(buf, sizeof(buf), fp)) {
  93                 char hexa[256];
  94                 struct ma_info m;
  95                 int len;
  96                 int st;
  97
  98                 memset(&m, 0, sizeof(m));
  99                 sscanf(buf, "%d%s%d%d%s", &m.index, m.name, &m.users, &st,
 100                        hexa);
 101                 if (filter.dev && strcmp(filter.dev, m.name))
 102                         continue;
 103
 104                 m.addr.family = AF_PACKET;
 105
 106                 len = parse_hex(hexa, (unsigned char*)&m.addr.data);
 107                 if (len >= 0) {
 108                         struct ma_info *ma = malloc(sizeof(m));
 109
 110                         memcpy(ma, &m, sizeof(m));
 111                         ma->addr.bytelen = len;
 112                         ma->addr.bitlen = len<<3;
 113                         if (st)
 114                                 ma->features = "static";
 115                         maddr_ins(result_p, ma);
 116                 }
 117         }
 118         fclose(fp);
 119 }
 120
 121 void read_igmp(struct ma_info **result_p)
 122 {
 123         struct ma_info m;
 124         char buf[256];
 125         FILE *fp = fopen("/proc/net/igmp", "r");
 126
 127         if (!fp)
 128                 return;
 129         memset(&m, 0, sizeof(m));
 130         fgets(buf, sizeof(buf), fp);
 131
 132         m.addr.family = AF_INET;
 133         m.addr.bitlen = 32;
 134         m.addr.bytelen = 4;
 135
 136         while (fgets(buf, sizeof(buf), fp)) {
 137                 struct ma_info *ma = malloc(sizeof(m));
 138
 139                 if (buf[0] != '\t') {
 140                         sscanf(buf, "%d%s", &m.index, m.name);
 141                         continue;
 142                 }
 143
 144                 if (filter.dev && strcmp(filter.dev, m.name))
 145                         continue;
 146
 147                 sscanf(buf, "%08x%d", (__u32*)&m.addr.data, &m.users);
 148
 149                 ma = malloc(sizeof(m));
 150                 memcpy(ma, &m, sizeof(m));
 151                 maddr_ins(result_p, ma);
 152         }
 153         fclose(fp);
 154 }
 155
 156
 157 void read_igmp6(struct ma_info **result_p)
 158 {
 159         char buf[256];
 160         FILE *fp = fopen("/proc/net/igmp6", "r");
 161
 162         if (!fp)
 163                 return;
 164
 165         while (fgets(buf, sizeof(buf), fp)) {
 166                 char hexa[256];
 167                 struct ma_info m;
 168                 int len;
 169
 170                 memset(&m, 0, sizeof(m));
 171                 sscanf(buf, "%d%s%s%d", &m.index, m.name, hexa, &m.users);
 172
 173                 if (filter.dev && strcmp(filter.dev, m.name))
 174                         continue;
 175
 176                 m.addr.family = AF_INET6;
 177
 178                 len = parse_hex(hexa, (unsigned char*)&m.addr.data);
 179                 if (len >= 0) {
 180                         struct ma_info *ma = malloc(sizeof(m));
 181
 182                         memcpy(ma, &m, sizeof(m));
 183
 184                         ma->addr.bytelen = len;
 185                         ma->addr.bitlen = len<<3;
 186                         maddr_ins(result_p, ma);
 187                 }
 188         }
 189         fclose(fp);
 190 }
 191
 192 static void print_maddr(FILE *fp, struct ma_info *list)
 193 {
 194         fprintf(fp, "\t");
 195
 196         if (list->addr.family == AF_PACKET) {
 197                 SPRINT_BUF(b1);
 198                 fprintf(fp, "link  %s", ll_addr_n2a((unsigned char*)list->addr.data,
 199                                                     list->addr.bytelen, 0,
 200                                                     b1, sizeof(b1)));
 201         } else {
 202                 char abuf[256];
 203                 switch(list->addr.family) {
 204                 case AF_INET:
 205                         fprintf(fp, "inet  ");
 206                         break;
 207                 case AF_INET6:
 208                         fprintf(fp, "inet6 ");
 209                         break;
 210                 default:
 211                         fprintf(fp, "family %d ", list->addr.family);
 212                         break;
 213                 }
 214                 fprintf(fp, "%s",
 215                         format_host(list->addr.family,
 216                                     -1,
 217                                     list->addr.data,
 218                                     abuf, sizeof(abuf)));
 219         }
 220         if (list->users != 1)
 221                 fprintf(fp, " users %d", list->users);
 222         if (list->features)
 223                 fprintf(fp, " %s", list->features);
 224         fprintf(fp, "\n");
 225 }
 226
 227 static void print_mlist(FILE *fp, struct ma_info *list)
 228 {
 229         int cur_index = 0;
 230
 231         for (; list; list = list->next) {
 232                 if (oneline) {
 233                         cur_index = list->index;
 234                         fprintf(fp, "%d:\t%s%s", cur_index, list->name, _SL_);
 235                 } else if (cur_index != list->index) {
 236                         cur_index = list->index;
 237                         fprintf(fp, "%d:\t%s\n", cur_index, list->name);
 238                 }
 239                 print_maddr(fp, list);
 240         }
 241 }
 242
 243 static int multiaddr_list(int argc, char **argv)
 244 {
 245         struct ma_info *list = NULL;
 246
 247         if (!filter.family)
 248                 filter.family = preferred_family;
 249
 250         while (argc > 0) {
 251                 if (1) {
 252                         if (strcmp(*argv, "dev") == 0) {
 253                                 NEXT_ARG();
 254                         }
 255                         if (matches(*argv, "help") == 0)
 256                                 usage();
 257                         if (filter.dev)
 258                                 duparg2("dev", *argv);
 259                         filter.dev = *argv;
 260                 }
 261                 argv++; argc--;
 262         }
 263
 264         if (!filter.family || filter.family == AF_PACKET)
 265                 read_dev_mcast(&list);
 266         if (!filter.family || filter.family == AF_INET)
 267                 read_igmp(&list);
 268         if (!filter.family || filter.family == AF_INET6)
 269                 read_igmp6(&list);
 270         print_mlist(stdout, list);
 271         return 0;
 272 }
 273
 274 int multiaddr_modify(int cmd, int argc, char **argv)
 275 {
 276         struct ifreq ifr;
 277         int fd;
 278
 279         memset(&ifr, 0, sizeof(ifr));
 280
 281         if (cmd == RTM_NEWADDR)
 282                 cmd = SIOCADDMULTI;
 283         else
 284                 cmd = SIOCDELMULTI;
 285
 286         while (argc > 0) {
 287                 if (strcmp(*argv, "dev") == 0) {
 288                         NEXT_ARG();
 289                         if (ifr.ifr_name[0])
 290                                 duparg("dev", *argv);
 291                         strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
 292                 } else {
 293                         if (matches(*argv, "address") == 0) {
 294                                 NEXT_ARG();
 295                         }
 296                         if (matches(*argv, "help") == 0)
 297                                 usage();
 298                         if (ifr.ifr_hwaddr.sa_data[0])
 299                                 duparg("address", *argv);
 300                         if (ll_addr_a2n(ifr.ifr_hwaddr.sa_data, 14, *argv) < 0) {
 301                                 fprintf(stderr, "Error: \"%s\" is not a legal ll address.\n", *argv);
 302                                 exit(1);
 303                         }
 304                 }
 305                 argc--; argv++;
 306         }
 307         if (ifr.ifr_name[0] == 0) {
 308                 fprintf(stderr, "Not enough information: \"dev\" is required.\n");
 309                 exit(-1);
 310         }
 311
 312         fd = socket(AF_INET, SOCK_DGRAM, 0);
 313         if (fd < 0) {
 314                 perror("Cannot create socket");
 315                 exit(1);
 316         }
 317         if (ioctl(fd, cmd, (char*)&ifr) != 0) {
 318                 perror("ioctl");
 319                 exit(1);
 320         }
 321         close(fd);
 322
 323         exit(0);
 324 }
 325
 326
 327 int do_multiaddr(int argc, char **argv)
 328 {
 329         if (argc < 1)
 330                 return multiaddr_list(0, NULL);
 331         if (matches(*argv, "add") == 0)
 332                 return multiaddr_modify(RTM_NEWADDR, argc-1, argv+1);
 333         if (matches(*argv, "delete") == 0)
 334                 return multiaddr_modify(RTM_DELADDR, argc-1, argv+1);
 335         if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
 336             || matches(*argv, "lst") == 0)
 337                 return multiaddr_list(argc-1, argv+1);
 338         if (matches(*argv, "help") == 0)
 339                 usage();
 340         fprintf(stderr, "Command \"%s\" is unknown, try \"ip maddr help\".\n", *argv);
 341         exit(-1);
 342 }