1 /* vi: set sw=4 ts=4: */
2 /*
3 * This program is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU General Public License
5 * as published by the Free Software Foundation; either version
6 * 2 of the License, or (at your option) any later version.
7 *
8 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
9 */
10 #include <net/if.h> /* struct ifreq and co. */
11
12 #include "libbb.h"
13 #include "libnetlink.h"
14 #include "ll_map.h"
15
16 struct idxmap {
17 struct idxmap *next;
18 int index;
19 int type;
20 int alen;
21 unsigned flags;
22 unsigned char addr[8];
23 char name[16];
24 };
25
26 static struct idxmap **idxmap; /* treat as *idxmap[16] */
27
find_by_index(int idx)28 static struct idxmap *find_by_index(int idx)
29 {
30 struct idxmap *im;
31
32 if (idxmap)
33 for (im = idxmap[idx & 0xF]; im; im = im->next)
34 if (im->index == idx)
35 return im;
36 return NULL;
37 }
38
ll_remember_index(const struct sockaddr_nl * who UNUSED_PARAM,struct nlmsghdr * n,void * arg UNUSED_PARAM)39 int FAST_FUNC ll_remember_index(const struct sockaddr_nl *who UNUSED_PARAM,
40 struct nlmsghdr *n,
41 void *arg UNUSED_PARAM)
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 //memset(tb, 0, sizeof(tb)); - parse_rtattr does this
55 parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
56 if (tb[IFLA_IFNAME] == NULL)
57 return 0;
58
59 if (!idxmap)
60 idxmap = xzalloc(sizeof(idxmap[0]) * 16);
61
62 h = ifi->ifi_index & 0xF;
63 for (imp = &idxmap[h]; (im = *imp) != NULL; imp = &im->next)
64 if (im->index == ifi->ifi_index)
65 goto found;
66
67 im = xmalloc(sizeof(*im));
68 im->next = *imp;
69 im->index = ifi->ifi_index;
70 *imp = im;
71 found:
72 im->type = ifi->ifi_type;
73 im->flags = ifi->ifi_flags;
74 if (tb[IFLA_ADDRESS]) {
75 int alen;
76 im->alen = alen = RTA_PAYLOAD(tb[IFLA_ADDRESS]);
77 if (alen > (int)sizeof(im->addr))
78 alen = sizeof(im->addr);
79 memcpy(im->addr, RTA_DATA(tb[IFLA_ADDRESS]), alen);
80 } else {
81 im->alen = 0;
82 memset(im->addr, 0, sizeof(im->addr));
83 }
84 strcpy(im->name, RTA_DATA(tb[IFLA_IFNAME]));
85 return 0;
86 }
87
88 static
ll_idx_n2a(int idx)89 const char FAST_FUNC *ll_idx_n2a(int idx/*, char *buf*/)
90 {
91 struct idxmap *im;
92
93 if (idx == 0)
94 return "*";
95 im = find_by_index(idx);
96 if (im)
97 return im->name;
98 //snprintf(buf, 16, "if%d", idx);
99 //return buf;
100 return auto_string(xasprintf("if%d", idx));
101 }
102
ll_index_to_name(int idx)103 const char FAST_FUNC *ll_index_to_name(int idx)
104 {
105 //static char nbuf[16];
106 return ll_idx_n2a(idx/*, nbuf*/);
107 }
108
109 #ifdef UNUSED
ll_index_to_type(int idx)110 int ll_index_to_type(int idx)
111 {
112 struct idxmap *im;
113
114 if (idx == 0)
115 return -1;
116 im = find_by_index(idx);
117 if (im)
118 return im->type;
119 return -1;
120 }
121 #endif
122
ll_index_to_flags(int idx)123 unsigned FAST_FUNC ll_index_to_flags(int idx)
124 {
125 struct idxmap *im;
126
127 if (idx == 0)
128 return 0;
129 im = find_by_index(idx);
130 if (im)
131 return im->flags;
132 return 0;
133 }
134
xll_name_to_index(const char * name)135 int FAST_FUNC xll_name_to_index(const char *name)
136 {
137 int ret = 0;
138
139 /* caching is not warranted - no users which repeatedly call it */
140 #ifdef UNUSED
141 static char ncache[16];
142 static int icache;
143
144 struct idxmap *im;
145 int i;
146
147 if (name == NULL)
148 goto out;
149 if (icache && strcmp(name, ncache) == 0) {
150 ret = icache;
151 goto out;
152 }
153 if (idxmap) {
154 for (i = 0; i < 16; i++) {
155 for (im = idxmap[i]; im; im = im->next) {
156 if (strcmp(im->name, name) == 0) {
157 icache = im->index;
158 strcpy(ncache, name);
159 ret = im->index;
160 goto out;
161 }
162 }
163 }
164 }
165 #endif
166 ret = if_nametoindex(name);
167 /* out:*/
168 if (ret <= 0)
169 bb_error_msg_and_die("can't find device '%s'", name);
170 return ret;
171 }
172
ll_init_map(struct rtnl_handle * rth)173 int FAST_FUNC ll_init_map(struct rtnl_handle *rth)
174 {
175 xrtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK);
176 xrtnl_dump_filter(rth, ll_remember_index, NULL);
177 return 0;
178 }
179