1/*
2 * ll_map.c
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/socket.h>
19#include <netinet/in.h>
20#include <string.h>
21
22#include "libnetlink.h"
23#include "ll_map.h"
24
25extern unsigned int if_nametoindex (const char *);
26
27struct idxmap
28{
29	struct idxmap * next;
30	unsigned	index;
31	int		type;
32	int		alen;
33	unsigned	flags;
34	unsigned char	addr[20];
35	char		name[16];
36};
37
38static struct idxmap *idxmap[16];
39
40int ll_remember_index(const struct sockaddr_nl *who,
41		      struct nlmsghdr *n, void *arg)
42{
43	int h;
44	struct ifinfomsg *ifi = NLMSG_DATA(n);
45	struct idxmap *im, **imp;
46	struct rtattr *tb[IFLA_MAX+1];
47
48	if (n->nlmsg_type != RTM_NEWLINK)
49		return 0;
50
51	if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi)))
52		return -1;
53
54
55	memset(tb, 0, sizeof(tb));
56	parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
57	if (tb[IFLA_IFNAME] == NULL)
58		return 0;
59
60	h = ifi->ifi_index&0xF;
61
62	for (imp=&idxmap[h]; (im=*imp)!=NULL; imp = &im->next)
63		if (im->index == ifi->ifi_index)
64			break;
65
66	if (im == NULL) {
67		im = malloc(sizeof(*im));
68		if (im == NULL)
69			return 0;
70		im->next = *imp;
71		im->index = ifi->ifi_index;
72		*imp = im;
73	}
74
75	im->type = ifi->ifi_type;
76	im->flags = ifi->ifi_flags;
77	if (tb[IFLA_ADDRESS]) {
78		int alen;
79		im->alen = alen = RTA_PAYLOAD(tb[IFLA_ADDRESS]);
80		if (alen > sizeof(im->addr))
81			alen = sizeof(im->addr);
82		memcpy(im->addr, RTA_DATA(tb[IFLA_ADDRESS]), alen);
83	} else {
84		im->alen = 0;
85		memset(im->addr, 0, sizeof(im->addr));
86	}
87	strcpy(im->name, RTA_DATA(tb[IFLA_IFNAME]));
88	return 0;
89}
90
91const char *ll_idx_n2a(unsigned idx, char *buf)
92{
93	struct idxmap *im;
94
95	if (idx == 0)
96		return "*";
97	for (im = idxmap[idx&0xF]; im; im = im->next)
98		if (im->index == idx)
99			return im->name;
100	snprintf(buf, 16, "if%d", idx);
101	return buf;
102}
103
104
105const char *ll_index_to_name(unsigned idx)
106{
107	static char nbuf[16];
108
109	return ll_idx_n2a(idx, nbuf);
110}
111
112int ll_index_to_type(unsigned idx)
113{
114	struct idxmap *im;
115
116	if (idx == 0)
117		return -1;
118	for (im = idxmap[idx&0xF]; im; im = im->next)
119		if (im->index == idx)
120			return im->type;
121	return -1;
122}
123
124unsigned ll_index_to_flags(unsigned idx)
125{
126	struct idxmap *im;
127
128	if (idx == 0)
129		return 0;
130
131	for (im = idxmap[idx&0xF]; im; im = im->next)
132		if (im->index == idx)
133			return im->flags;
134	return 0;
135}
136
137unsigned ll_index_to_addr(unsigned idx, unsigned char *addr,
138			  unsigned alen)
139{
140	struct idxmap *im;
141
142	if (idx == 0)
143		return 0;
144
145	for (im = idxmap[idx&0xF]; im; im = im->next) {
146		if (im->index == idx) {
147			if (alen > sizeof(im->addr))
148				alen = sizeof(im->addr);
149			if (alen > im->alen)
150				alen = im->alen;
151			memcpy(addr, im->addr, alen);
152			return alen;
153		}
154	}
155	return 0;
156}
157
158unsigned ll_name_to_index(const char *name)
159{
160	static char ncache[16];
161	static int icache;
162	struct idxmap *im;
163	int i;
164	unsigned idx;
165
166	if (name == NULL)
167		return 0;
168	if (icache && strcmp(name, ncache) == 0)
169		return icache;
170	for (i=0; i<16; i++) {
171		for (im = idxmap[i]; im; im = im->next) {
172			if (strcmp(im->name, name) == 0) {
173				icache = im->index;
174				strcpy(ncache, name);
175				return im->index;
176			}
177		}
178	}
179
180	idx = if_nametoindex(name);
181	if (idx == 0)
182		sscanf(name, "if%u", &idx);
183	return idx;
184}
185
186int ll_init_map(struct rtnl_handle *rth)
187{
188	if (rtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK) < 0) {
189		perror("Cannot send dump request");
190		exit(1);
191	}
192
193	if (rtnl_dump_filter(rth, ll_remember_index, &idxmap, NULL, NULL) < 0) {
194		fprintf(stderr, "Dump terminated\n");
195		exit(1);
196	}
197	return 0;
198}
199