text: /*
   * ipmaddr.c		"ip maddress".
   *
   *		This program is free software; you can redistribute it and/or
   *		modify it under the terms of the GNU General Public License
   *		as published by the Free Software Foundation; either version
   *		2 of the License, or (at your option) any later version.
   *
   * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   *
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <syslog.h>
  #include <fcntl.h>
  #include <sys/ioctl.h>
  #include <sys/socket.h>
  #include <netinet/in.h>
  #include <arpa/inet.h>
  #include <string.h>
  
  #include <linux/netdevice.h>
  #include <linux/if.h>
  #include <linux/if_arp.h>
  #include <linux/sockios.h>
  
  #include "rt_names.h"
  #include "utils.h"
  
  static struct {
  	char *dev;
  	int  family;
  } filter;
  
  static void usage(void) __attribute__((noreturn));
  
  static void usage(void)
  {
  	fprintf(stderr, "Usage: ip maddr [ add | del ] MULTIADDR dev STRING\n");
  	fprintf(stderr, "       ip maddr show [ dev STRING ]\n");
  	exit(-1);
  }
  
  static int parse_hex(char *str, unsigned char *addr, size_t size)
  {
  	int len=0;
  
  	while (*str && (len < 2 * size)) {
  		int tmp;
  		if (str[1] == 0)
  			return -1;
  		if (sscanf(str, "%02x", &tmp) != 1)
  			return -1;
  		addr[len] = tmp;
  		len++;
  		str += 2;
  	}
  	return len;
  }
  
  struct ma_info
  {
  	struct ma_info *next;
  	int		index;
  	int		users;
  	char		*features;
  	char		name[IFNAMSIZ];
  	inet_prefix	addr;
  };
  
  void maddr_ins(struct ma_info **lst, struct ma_info *m)
  {
  	struct ma_info *mp;
  
  	for (; (mp=*lst) != NULL; lst = &mp->next) {
  		if (mp->index > m->index)
  			break;
  	}
  	m->next = *lst;
  	*lst = m;
  }
  
  void read_dev_mcast(struct ma_info **result_p)
  {
  	char buf[256];
  	FILE *fp = fopen("/proc/net/dev_mcast", "r");
  
  	if (!fp)
  		return;
  
  	while (fgets(buf, sizeof(buf), fp)) {
  		char hexa[256];
  		struct ma_info m;
  		int len;
  		int st;
  
  		memset(&m, 0, sizeof(m));
  		sscanf(buf, "%d%s%d%d%s", &m.index, m.name, &m.users, &st,
  		       hexa);
  		if (filter.dev && strcmp(filter.dev, m.name))
  			continue;
  
  		m.addr.family = AF_PACKET;
  
  		len = parse_hex(hexa, (unsigned char*)&m.addr.data, sizeof (m.addr.data));
  		if (len >= 0) {
  			struct ma_info *ma = malloc(sizeof(m));
  
  			memcpy(ma, &m, sizeof(m));
  			ma->addr.bytelen = len;
  			ma->addr.bitlen = len<<3;
  			if (st)
  				ma->features = "static";
  			maddr_ins(result_p, ma);
  		}
  	}
  	fclose(fp);
  }
  
  void read_igmp(struct ma_info **result_p)
  {
  	struct ma_info m;
  	char buf[256];
  	FILE *fp = fopen("/proc/net/igmp", "r");
  
  	if (!fp)
  		return;
  	memset(&m, 0, sizeof(m));
  	fgets(buf, sizeof(buf), fp);
  
  	m.addr.family = AF_INET;
  	m.addr.bitlen = 32;
  	m.addr.bytelen = 4;
  
  	while (fgets(buf, sizeof(buf), fp)) {
  		struct ma_info *ma = malloc(sizeof(m));
  
  		if (buf[0] != '\t') {
  			sscanf(buf, "%d%s", &m.index, m.name);
  			continue;
  		}
  
  		if (filter.dev && strcmp(filter.dev, m.name))
  			continue;
  
  		sscanf(buf, "%08x%d", (__u32*)&m.addr.data, &m.users);
  
  		ma = malloc(sizeof(m));
  		memcpy(ma, &m, sizeof(m));
  		maddr_ins(result_p, ma);
  	}
  	fclose(fp);
  }
  
  
  void read_igmp6(struct ma_info **result_p)
  {
  	char buf[256];
  	FILE *fp = fopen("/proc/net/igmp6", "r");
  
  	if (!fp)
  		return;
  
  	while (fgets(buf, sizeof(buf), fp)) {
  		char hexa[256];
  		struct ma_info m;
  		int len;
  
  		memset(&m, 0, sizeof(m));
  		sscanf(buf, "%d%s%s%d", &m.index, m.name, hexa, &m.users);
  
  		if (filter.dev && strcmp(filter.dev, m.name))
  			continue;
  
  		m.addr.family = AF_INET6;
  
  		len = parse_hex(hexa, (unsigned char*)&m.addr.data, sizeof (m.addr.data));
  		if (len >= 0) {
  			struct ma_info *ma = malloc(sizeof(m));
  
  			memcpy(ma, &m, sizeof(m));
  
  			ma->addr.bytelen = len;
  			ma->addr.bitlen = len<<3;
  			maddr_ins(result_p, ma);
  		}
  	}
  	fclose(fp);
  }
  
  static void print_maddr(FILE *fp, struct ma_info *list)
  {
  	fprintf(fp, "\t");
  
  	if (list->addr.family == AF_PACKET) {
  		SPRINT_BUF(b1);
  		fprintf(fp, "link  %s", ll_addr_n2a((unsigned char*)list->addr.data,
  						    list->addr.bytelen, 0,
  						    b1, sizeof(b1)));
  	} else {
  		char abuf[256];
  		switch(list->addr.family) {
  		case AF_INET:
  			fprintf(fp, "inet  ");
  			break;
  		case AF_INET6:
  			fprintf(fp, "inet6 ");
  			break;
  		default:
  			fprintf(fp, "family %d ", list->addr.family);
  			break;
  		}
  		fprintf(fp, "%s",
  			format_host(list->addr.family,
  				    -1,
  				    list->addr.data,
  				    abuf, sizeof(abuf)));
  	}
  	if (list->users != 1)
  		fprintf(fp, " users %d", list->users);
  	if (list->features)
  		fprintf(fp, " %s", list->features);
  	fprintf(fp, "\n");
  }
  
  static void print_mlist(FILE *fp, struct ma_info *list)
  {
  	int cur_index = 0;
  
  	for (; list; list = list->next) {
  		if (oneline) {
  			cur_index = list->index;
  			fprintf(fp, "%d:\t%s%s", cur_index, list->name, _SL_);
  		} else if (cur_index != list->index) {
  			cur_index = list->index;
  			fprintf(fp, "%d:\t%s\n", cur_index, list->name);
  		}
  		print_maddr(fp, list);
  	}
  }
  
  static int multiaddr_list(int argc, char **argv)
  {
  	struct ma_info *list = NULL;
  
  	if (!filter.family)
  		filter.family = preferred_family;
  
  	while (argc > 0) {
  		if (1) {
  			if (strcmp(*argv, "dev") == 0) {
  				NEXT_ARG();
  			}
  			if (matches(*argv, "help") == 0)
  				usage();
  			if (filter.dev)
  				duparg2("dev", *argv);
  			filter.dev = *argv;
  		}
  		argv++; argc--;
  	}
  
  	if (!filter.family || filter.family == AF_PACKET)
  		read_dev_mcast(&list);
  	if (!filter.family || filter.family == AF_INET)
  		read_igmp(&list);
  	if (!filter.family || filter.family == AF_INET6)
  		read_igmp6(&list);
  	print_mlist(stdout, list);
  	return 0;
  }
  
  int multiaddr_modify(int cmd, int argc, char **argv)
  {
  	struct ifreq ifr;
  	int fd;
  
  	memset(&ifr, 0, sizeof(ifr));
  
  	if (cmd == RTM_NEWADDR)
  		cmd = SIOCADDMULTI;
  	else
  		cmd = SIOCDELMULTI;
  
  	while (argc > 0) {
  		if (strcmp(*argv, "dev") == 0) {
  			NEXT_ARG();
  			if (ifr.ifr_name[0])
  				duparg("dev", *argv);
  			strncpy(ifr.ifr_name, *argv, IFNAMSIZ);
  		} else {
  			if (matches(*argv, "address") == 0) {
  				NEXT_ARG();
  			}
  			if (matches(*argv, "help") == 0)
  				usage();
  			if (ifr.ifr_hwaddr.sa_data[0])
  				duparg("address", *argv);
  			if (ll_addr_a2n(ifr.ifr_hwaddr.sa_data,
  					14, *argv) < 0) {
  				fprintf(stderr, "Error: \"%s\" is not a legal ll address.\n", *argv);
  				exit(1);
  			}
  		}
  		argc--; argv++;
  	}
  	if (ifr.ifr_name[0] == 0) {
  		fprintf(stderr, "Not enough information: \"dev\" is required.\n");
  		exit(-1);
  	}
  
  	fd = socket(AF_INET, SOCK_DGRAM, 0);
  	if (fd < 0) {
  		perror("Cannot create socket");
  		exit(1);
  	}
  	if (ioctl(fd, cmd, (char*)&ifr) != 0) {
  		perror("ioctl");
  		exit(1);
  	}
  	close(fd);
  
  	exit(0);
  }
  
  
  int do_multiaddr(int argc, char **argv)
  {
  	if (argc < 1)
  		return multiaddr_list(0, NULL);
  	if (matches(*argv, "add") == 0)
  		return multiaddr_modify(RTM_NEWADDR, argc-1, argv+1);
  	if (matches(*argv, "delete") == 0)
  		return multiaddr_modify(RTM_DELADDR, argc-1, argv+1);
  	if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
  	    || matches(*argv, "lst") == 0)
  		return multiaddr_list(argc-1, argv+1);
  	if (matches(*argv, "help") == 0)
  		usage();
  	fprintf(stderr, "Command \"%s\" is unknown, try \"ip maddr help\".\n", *argv);
  	exit(-1);
  }
  