1/*
2 * ipnetconf.c		"ip netconf".
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:	Nicolas Dichtel, <nicolas.dichtel@6wind.com>
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 <string.h>
19#include <sys/time.h>
20#include <sys/socket.h>
21#include <netinet/in.h>
22
23#include "rt_names.h"
24#include "utils.h"
25#include "ip_common.h"
26
27static struct
28{
29	int family;
30	int ifindex;
31} filter;
32
33static void usage(void) __attribute__((noreturn));
34
35static void usage(void)
36{
37	fprintf(stderr, "Usage: ip netconf show [ dev STRING ]\n");
38	exit(-1);
39}
40
41#define NETCONF_RTA(r)	((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct netconfmsg))))
42
43int print_netconf(const struct sockaddr_nl *who, struct rtnl_ctrl_data *ctrl,
44		  struct nlmsghdr *n, void *arg)
45{
46	FILE *fp = (FILE*)arg;
47	struct netconfmsg *ncm = NLMSG_DATA(n);
48	int len = n->nlmsg_len;
49	struct rtattr *tb[NETCONFA_MAX+1];
50
51	if (n->nlmsg_type == NLMSG_ERROR)
52		return -1;
53	if (n->nlmsg_type != RTM_NEWNETCONF) {
54		fprintf(stderr, "Not RTM_NEWNETCONF: %08x %08x %08x\n",
55			n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
56
57		return -1;
58	}
59	len -= NLMSG_SPACE(sizeof(*ncm));
60	if (len < 0) {
61		fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
62		return -1;
63	}
64
65	if (filter.family && filter.family != ncm->ncm_family)
66		return 0;
67
68	parse_rtattr(tb, NETCONFA_MAX, NETCONF_RTA(ncm),
69		     NLMSG_PAYLOAD(n, sizeof(*ncm)));
70
71	switch (ncm->ncm_family) {
72	case AF_INET:
73		fprintf(fp, "ipv4 ");
74		break;
75	case AF_INET6:
76		fprintf(fp, "ipv6 ");
77		break;
78	default:
79		fprintf(fp, "unknown ");
80		break;
81	}
82
83	if (tb[NETCONFA_IFINDEX]) {
84		int *ifindex = (int *)RTA_DATA(tb[NETCONFA_IFINDEX]);
85
86		switch (*ifindex) {
87		case NETCONFA_IFINDEX_ALL:
88			fprintf(fp, "all ");
89			break;
90		case NETCONFA_IFINDEX_DEFAULT:
91			fprintf(fp, "default ");
92			break;
93		default:
94			fprintf(fp, "dev %s ", ll_index_to_name(*ifindex));
95			break;
96		}
97	}
98
99	if (tb[NETCONFA_FORWARDING])
100		fprintf(fp, "forwarding %s ",
101			*(int *)RTA_DATA(tb[NETCONFA_FORWARDING])?"on":"off");
102	if (tb[NETCONFA_RP_FILTER]) {
103		int rp_filter = *(int *)RTA_DATA(tb[NETCONFA_RP_FILTER]);
104
105		if (rp_filter == 0)
106			fprintf(fp, "rp_filter off ");
107		else if (rp_filter == 1)
108			fprintf(fp, "rp_filter strict ");
109		else if (rp_filter == 2)
110			fprintf(fp, "rp_filter loose ");
111		else
112			fprintf(fp, "rp_filter unknown mode ");
113	}
114	if (tb[NETCONFA_MC_FORWARDING])
115		fprintf(fp, "mc_forwarding %d ",
116			*(int *)RTA_DATA(tb[NETCONFA_MC_FORWARDING]));
117
118	if (tb[NETCONFA_PROXY_NEIGH])
119		fprintf(fp, "proxy_neigh %s ",
120			*(int *)RTA_DATA(tb[NETCONFA_PROXY_NEIGH])?"on":"off");
121
122	fprintf(fp, "\n");
123	fflush(fp);
124	return 0;
125}
126
127static int print_netconf2(const struct sockaddr_nl *who,
128			  struct nlmsghdr *n, void *arg)
129{
130	return print_netconf(who, NULL, n, arg);
131}
132
133void ipnetconf_reset_filter(int ifindex)
134{
135	memset(&filter, 0, sizeof(filter));
136	filter.ifindex = ifindex;
137}
138
139static int do_show(int argc, char **argv)
140{
141	struct {
142		struct nlmsghdr		n;
143		struct netconfmsg	ncm;
144		char			buf[1024];
145	} req;
146
147	ipnetconf_reset_filter(0);
148	filter.family = preferred_family;
149	if (filter.family == AF_UNSPEC)
150		filter.family = AF_INET;
151
152	while (argc > 0) {
153		if (strcmp(*argv, "dev") == 0) {
154			NEXT_ARG();
155			filter.ifindex = ll_name_to_index(*argv);
156			if (filter.ifindex <= 0) {
157				fprintf(stderr, "Device \"%s\" does not exist.\n",
158					*argv);
159				return -1;
160			}
161		}
162		argv++; argc--;
163	}
164
165	ll_init_map(&rth);
166	if (filter.ifindex) {
167		memset(&req, 0, sizeof(req));
168		req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct netconfmsg));
169		req.n.nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK;
170		req.n.nlmsg_type = RTM_GETNETCONF;
171		req.ncm.ncm_family = filter.family;
172		if (filter.ifindex)
173			addattr_l(&req.n, sizeof(req), NETCONFA_IFINDEX,
174				  &filter.ifindex, sizeof(filter.ifindex));
175
176		if (rtnl_send(&rth, &req.n, req.n.nlmsg_len) < 0) {
177			perror("Can not send request");
178			exit(1);
179		}
180		rtnl_listen(&rth, print_netconf, stdout);
181	} else {
182dump:
183		if (rtnl_wilddump_request(&rth, filter.family, RTM_GETNETCONF) < 0) {
184			perror("Cannot send dump request");
185			exit(1);
186		}
187		if (rtnl_dump_filter(&rth, print_netconf2, stdout) < 0) {
188			fprintf(stderr, "Dump terminated\n");
189			exit(1);
190		}
191		if (preferred_family == AF_UNSPEC) {
192			preferred_family = AF_INET6;
193			filter.family = AF_INET6;
194			goto dump;
195		}
196	}
197	return 0;
198}
199
200int do_ipnetconf(int argc, char **argv)
201{
202	if (argc > 0) {
203		if (matches(*argv, "show") == 0 ||
204		    matches(*argv, "lst") == 0 ||
205		    matches(*argv, "list") == 0)
206			return do_show(argc-1, argv+1);
207		if (matches(*argv, "help") == 0)
208			usage();
209	} else
210		return do_show(0, NULL);
211
212	fprintf(stderr, "Command \"%s\" is unknown, try \"ip netconf help\".\n", *argv);
213	exit(-1);
214}
215