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 <netinet/in.h>
  21 #include <arpa/inet.h>
  22 #include <string.h>
  23
  24 #include <linux/netdevice.h>
  25 #include <linux/if.h>
  26 #include <linux/if_arp.h>
  27 #include <linux/sockios.h>
  28
  29 #include "rt_names.h"
  30 #include "utils.h"
  31
  32 static struct {
  33         char *dev;
  34         int  family;
  35 } filter;
  36
  37 static void usage(void) __attribute__((noreturn));
  38
  39 static void usage(void)
  40 {
  41         fprintf(stderr, "Usage: ip maddr [ add | del ] MULTIADDR dev STRING\n");
  42         fprintf(stderr, "       ip maddr show [ dev STRING ]\n");
  43         exit(-1);
  44 }
  45
  46 static int parse_hex(char *str, unsigned char *addr, size_t size)
  47 {
  48         int len=0;
  49
  50         while (*str && (len < 2 * size)) {
  51                 int tmp;
  52                 if (str[1] == 0)
  53                         return -1;
  54                 if (sscanf(str, "%02x", &tmp) != 1)
  55                         return -1;
  56                 addr[len] = tmp;
  57                 len++;
  58                 str += 2;
  59         }
  60         return len;
  61 }
  62
  63 struct ma_info
  64 {
  65         struct ma_info *next;
  66         int             index;
  67         int             users;
  68         char            *features;
  69         char            name[IFNAMSIZ];
  70         inet_prefix     addr;
  71 };
  72
  73 void maddr_ins(struct ma_info **lst, struct ma_info *m)
  74 {
  75         struct ma_info *mp;
  76
  77         for (; (mp=*lst) != NULL; lst = &mp->next) {
  78                 if (mp->index > m->index)
  79                         break;
  80         }
  81         m->next = *lst;
  82         *lst = m;
  83 }
  84
  85 void read_dev_mcast(struct ma_info **result_p)
  86 {
  87         char buf[256];
  88         FILE *fp = fopen("/proc/net/dev_mcast", "r");
  89
  90         if (!fp)
  91                 return;
  92
  93         while (fgets(buf, sizeof(buf), fp)) {
  94                 char hexa[256];
  95                 struct ma_info m;
  96                 int len;
  97                 int st;
  98
  99                 memset(&m, 0, sizeof(m));
 100                 sscanf(buf, "%d%s%d%d%s", &m.index, m.name, &m.users, &st,
 101                        hexa);
 102                 if (filter.dev && strcmp(filter.dev, m.name))
 103                         continue;
 104
 105                 m.addr.family = AF_PACKET;
 106
 107                 len = parse_hex(hexa, (unsigned char*)&m.addr.data, sizeof (m.addr.data));
 108                 if (len >= 0) {
 109                         struct ma_info *ma = malloc(sizeof(m));
 110
 111                         memcpy(ma, &m, sizeof(m));
 112                         ma->addr.bytelen = len;
 113                         ma->addr.bitlen = len<<3;
 114                         if (st)
 115                                 ma->features = "static";
 116                         maddr_ins(result_p, ma);
 117                 }
 118         }
 119         fclose(fp);
 120 }
 121
 122 void read_igmp(struct ma_info **result_p)
 123 {
 124         struct ma_info m;
 125         char buf[256];
 126         FILE *fp = fopen("/proc/net/igmp", "r");
 127
 128         if (!fp)
 129                 return;
 130         memset(&m, 0, sizeof(m));
 131         if (!fgets(buf, sizeof(buf), fp))
 132                 return;
 133
 134         m.addr.family = AF_INET;
 135         m.addr.bitlen = 32;
 136         m.addr.bytelen = 4;
 137
 138         while (fgets(buf, sizeof(buf), fp)) {
 139                 struct ma_info *ma;
 140
 141                 if (buf[0] != '\t') {
 142                         sscanf(buf, "%d%s", &m.index, m.name);
 143                         continue;
 144                 }
 145
 146                 if (filter.dev && strcmp(filter.dev, m.name))
 147                         continue;
 148
 149                 sscanf(buf, "%08x%d", (__u32*)&m.addr.data, &m.users);
 150
 151                 ma = malloc(sizeof(m));
 152                 memcpy(ma, &m, sizeof(m));
 153                 maddr_ins(result_p, ma);
 154         }
 155         fclose(fp);
 156 }
 157
 158
 159 void read_igmp6(struct ma_info **result_p)
 160 {
 161         char buf[256];
 162         FILE *fp = fopen("/proc/net/igmp6", "r");
 163
 164         if (!fp)
 165                 return;
 166
 167         while (fgets(buf, sizeof(buf), fp)) {
 168                 char hexa[256];
 169                 struct ma_info m;
 170                 int len;
 171
 172                 memset(&m, 0, sizeof(m));
 173                 sscanf(buf, "%d%s%s%d", &m.index, m.name, hexa, &m.users);
 174
 175                 if (filter.dev && strcmp(filter.dev, m.name))
 176                         continue;
 177
 178                 m.addr.family = AF_INET6;
 179
 180                 len = parse_hex(hexa, (unsigned char*)&m.addr.data, sizeof (m.addr.data));
 181                 if (len >= 0) {
 182                         struct ma_info *ma = malloc(sizeof(m));
 183
 184                         memcpy(ma, &m, sizeof(m));
 185
 186                         ma->addr.bytelen = len;
 187                         ma->addr.bitlen = len<<3;
 188                         maddr_ins(result_p, ma);
 189                 }
 190         }
 191         fclose(fp);
 192 }
 193
 194 static void print_maddr(FILE *fp, struct ma_info *list)
 195 {
 196         fprintf(fp, "\t");
 197
 198         if (list->addr.family == AF_PACKET) {
 199                 SPRINT_BUF(b1);
 200                 fprintf(fp, "link  %s", ll_addr_n2a((unsigned char*)list->addr.data,
 201                                                     list->addr.bytelen, 0,
 202                                                     b1, sizeof(b1)));
 203         } else {
 204                 char abuf[256];
 205                 switch(list->addr.family) {
 206                 case AF_INET:
 207                         fprintf(fp, "inet  ");
 208                         break;
 209                 case AF_INET6:
 210                         fprintf(fp, "inet6 ");
 211                         break;
 212                 default:
 213                         fprintf(fp, "family %d ", list->addr.family);
 214                         break;
 215                 }
 216                 fprintf(fp, "%s",
 217                         format_host(list->addr.family,
 218                                     -1,
 219                                     list->addr.data,
 220                                     abuf, sizeof(abuf)));
 221         }
 222         if (list->users != 1)
 223                 fprintf(fp, " users %d", list->users);
 224         if (list->features)
 225                 fprintf(fp, " %s", list->features);
 226         fprintf(fp, "\n");
 227 }
 228
 229 static void print_mlist(FILE *fp, struct ma_info *list)
 230 {
 231         int cur_index = 0;
 232
 233         for (; list; list = list->next) {
 234                 if (oneline) {
 235                         cur_index = list->index;
 236                         fprintf(fp, "%d:\t%s%s", cur_index, list->name, _SL_);
 237                 } else if (cur_index != list->index) {
 238                         cur_index = list->index;
 239                         fprintf(fp, "%d:\t%s\n", cur_index, list->name);
 240                 }
 241                 print_maddr(fp, list);
 242         }
 243 }
 244
 245 static int multiaddr_list(int argc, char **argv)
 246 {
 247         struct ma_info *list = NULL;
 248
 249         if (!filter.family)
 250                 filter.family = preferred_family;
 251
 252         while (argc > 0) {
 253                 if (1) {
 254                         if (strcmp(*argv, "dev") == 0) {
 255                                 NEXT_ARG();
 256                         }
 257                         if (matches(*argv, "help") == 0)
 258                                 usage();
 259                         if (filter.dev)
 260                                 duparg2("dev", *argv);
 261                         filter.dev = *argv;
 262                 }
 263                 argv++; argc--;
 264         }
 265
 266         if (!filter.family || filter.family == AF_PACKET)
 267                 read_dev_mcast(&list);
 268         if (!filter.family || filter.family == AF_INET)
 269                 read_igmp(&list);
 270         if (!filter.family || filter.family == AF_INET6)
 271                 read_igmp6(&list);
 272         print_mlist(stdout, list);
 273         return 0;
 274 }
 275
 276 int multiaddr_modify(int cmd, int argc, char **argv)
 277 {
 278         struct ifreq ifr;
 279         int fd;
 280
 281         memset(&ifr, 0, sizeof(ifr));
 282
 283         if (cmd == RTM_NEWADDR)
 284                 cmd = SIOCADDMULTI;
 285         else
 286                 cmd = SIOCDELMULTI;
 287
 288         while (argc > 0) {
 289                 if (strcmp(*argv, "dev") == 0) {
 290                         NEXT_ARG();
 291                         if (ifr.ifr_name[0])
 292                                 duparg("dev", *argv);
 293                         strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
 294                 } else {
 295                         if (matches(*argv, "address") == 0) {
 296                                 NEXT_ARG();
 297                         }
 298                         if (matches(*argv, "help") == 0)
 299                                 usage();
 300                         if (ifr.ifr_hwaddr.sa_data[0])
 301                                 duparg("address", *argv);
 302                         if (ll_addr_a2n(ifr.ifr_hwaddr.sa_data,
 303                                         14, *argv) < 0) {
 304                                 fprintf(stderr, "Error: \"%s\" is not a legal ll address.\n", *argv);
 305                                 exit(1);
 306                         }
 307                 }
 308                 argc--; argv++;
 309         }
 310         if (ifr.ifr_name[0] == 0) {
 311                 fprintf(stderr, "Not enough information: \"dev\" is required.\n");
 312                 exit(-1);
 313         }
 314
 315         fd = socket(AF_INET, SOCK_DGRAM, 0);
 316         if (fd < 0) {
 317                 perror("Cannot create socket");
 318                 exit(1);
 319         }
 320         if (ioctl(fd, cmd, (char*)&ifr) != 0) {
 321                 perror("ioctl");
 322                 exit(1);
 323         }
 324         close(fd);
 325
 326         exit(0);
 327 }
 328
 329
 330 int do_multiaddr(int argc, char **argv)
 331 {
 332         if (argc < 1)
 333                 return multiaddr_list(0, NULL);
 334         if (matches(*argv, "add") == 0)
 335                 return multiaddr_modify(RTM_NEWADDR, argc-1, argv+1);
 336         if (matches(*argv, "delete") == 0)
 337                 return multiaddr_modify(RTM_DELADDR, argc-1, argv+1);
 338         if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
 339             || matches(*argv, "lst") == 0)
 340                 return multiaddr_list(argc-1, argv+1);
 341         if (matches(*argv, "help") == 0)
 342                 usage();
 343         fprintf(stderr, "Command \"%s\" is unknown, try \"ip maddr help\".\n", *argv);
 344         exit(-1);
 345 }