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/*
* ll_map.c
*
* 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/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <linux/if.h>
#include "libnetlink.h"
#include "ll_map.h"
extern unsigned int if_nametoindex (const char *);
struct ll_cache
{
struct ll_cache *idx_next;
unsigned flags;
int index;
unsigned short type;
unsigned short alen;
char name[IFNAMSIZ];
unsigned char addr[20];
};
#define IDXMAP_SIZE 1024
static struct ll_cache *idx_head[IDXMAP_SIZE];
static inline struct ll_cache *idxhead(int idx)
{
return idx_head[idx & (IDXMAP_SIZE - 1)];
}
int ll_remember_index(const struct sockaddr_nl *who,
struct nlmsghdr *n, void *arg)
{
int h;
struct ifinfomsg *ifi = NLMSG_DATA(n);
struct ll_cache *im, **imp;
struct rtattr *tb[IFLA_MAX+1];
if (n->nlmsg_type != RTM_NEWLINK)
return 0;
if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi)))
return -1;
memset(tb, 0, sizeof(tb));
parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
if (tb[IFLA_IFNAME] == NULL)
return 0;
h = ifi->ifi_index & (IDXMAP_SIZE - 1);
for (imp = &idx_head[h]; (im=*imp)!=NULL; imp = &im->idx_next)
if (im->index == ifi->ifi_index)
break;
if (im == NULL) {
im = malloc(sizeof(*im));
if (im == NULL)
return 0;
im->idx_next = *imp;
im->index = ifi->ifi_index;
*imp = im;
}
im->type = ifi->ifi_type;
im->flags = ifi->ifi_flags;
if (tb[IFLA_ADDRESS]) {
int alen;
im->alen = alen = RTA_PAYLOAD(tb[IFLA_ADDRESS]);
if (alen > sizeof(im->addr))
alen = sizeof(im->addr);
memcpy(im->addr, RTA_DATA(tb[IFLA_ADDRESS]), alen);
} else {
im->alen = 0;
memset(im->addr, 0, sizeof(im->addr));
}
strcpy(im->name, RTA_DATA(tb[IFLA_IFNAME]));
return 0;
}
const char *ll_idx_n2a(unsigned idx, char *buf)
{
const struct ll_cache *im;
if (idx == 0)
return "*";
for (im = idxhead(idx); im; im = im->idx_next)
if (im->index == idx)
return im->name;
snprintf(buf, IFNAMSIZ, "if%d", idx);
return buf;
}
const char *ll_index_to_name(unsigned idx)
{
static char nbuf[IFNAMSIZ];
return ll_idx_n2a(idx, nbuf);
}
int ll_index_to_type(unsigned idx)
{
const struct ll_cache *im;
if (idx == 0)
return -1;
for (im = idxhead(idx); im; im = im->idx_next)
if (im->index == idx)
return im->type;
return -1;
}
unsigned ll_index_to_flags(unsigned idx)
{
const struct ll_cache *im;
if (idx == 0)
return 0;
for (im = idxhead(idx); im; im = im->idx_next)
if (im->index == idx)
return im->flags;
return 0;
}
unsigned ll_index_to_addr(unsigned idx, unsigned char *addr,
unsigned alen)
{
const struct ll_cache *im;
if (idx == 0)
return 0;
for (im = idxhead(idx); im; im = im->idx_next) {
if (im->index == idx) {
if (alen > sizeof(im->addr))
alen = sizeof(im->addr);
if (alen > im->alen)
alen = im->alen;
memcpy(addr, im->addr, alen);
return alen;
}
}
return 0;
}
unsigned ll_name_to_index(const char *name)
{
static char ncache[IFNAMSIZ];
static int icache;
struct ll_cache *im;
int i;
unsigned idx;
if (name == NULL)
return 0;
if (icache && strcmp(name, ncache) == 0)
return icache;
for (i=0; i<IDXMAP_SIZE; i++) {
for (im = idx_head[i]; im; im = im->idx_next) {
if (strcmp(im->name, name) == 0) {
icache = im->index;
strcpy(ncache, name);
return im->index;
}
}
}
idx = if_nametoindex(name);
if (idx == 0)
sscanf(name, "if%u", &idx);
return idx;
}
int ll_init_map(struct rtnl_handle *rth)
{
static int initialized;
if (initialized)
return 0;
if (rtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK) < 0) {
perror("Cannot send dump request");
exit(1);
}
if (rtnl_dump_filter(rth, ll_remember_index, NULL, NULL, NULL) < 0) {
fprintf(stderr, "Dump terminated\n");
exit(1);
}
initialized = 1;
return 0;
}
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