/**
|
* @file network_id.c
|
* @date 16 Sep 2014
|
* @brief File containing network interface detection functions for Linux.
|
*
|
* The only public function of this module is #getAdapterInfos(OsAdapterInfo *,
|
* size_t *), other functions are either static or inline.
|
*
|
* Responsibility of this module is to fill OsAdapterInfo structures, in a
|
* predictable way (skip "lo" interfaces,
|
* @TODO: place physical interfaces in front in a repeatable order: "eth", "wlan","ib"
|
* and other interfaces later, first the one with a a specified mac address, then
|
* the ones with only an ip.)
|
*/
|
|
#ifndef _GNU_SOURCE
|
#define _GNU_SOURCE /* To get defns of NI_MAXSERV and NI_MAXHOST */
|
#endif
|
#include <arpa/inet.h>
|
#include <sys/socket.h>
|
#include <netdb.h>
|
#include <ifaddrs.h>
|
#include <linux/if_link.h>
|
#include <netpacket/packet.h>
|
#include <string.h>
|
#include <stdio.h>
|
|
#include "os.h"
|
|
/**
|
*
|
* @param ifnames
|
* @param ifname
|
* @param ifnames_max
|
* @return
|
*/
|
|
static int ifname_position(char *ifnames, char * ifname, int ifnames_max) {
|
int i, position;
|
position = -1;
|
for (i = 0; i < ifnames_max; i++) {
|
if (strcmp(ifname, &ifnames[i * NI_MAXHOST]) == 0) {
|
position = i;
|
break;
|
}
|
}
|
return position;
|
}
|
|
/**
|
*
|
* @param adapterInfos
|
* @param adapter_info_size
|
* @return
|
*/
|
FUNCTION_RETURN getAdapterInfos(OsAdapterInfo * adapterInfos,
|
size_t * adapter_info_size) {
|
|
FUNCTION_RETURN f_return = FUNC_RET_OK;
|
struct ifaddrs *ifaddr, *ifa;
|
int family, n = 0, if_name_position;
|
unsigned int if_num, if_max;
|
//char host[NI_MAXHOST];
|
char *ifnames;
|
|
if (getifaddrs(&ifaddr) == -1) {
|
perror("getifaddrs");
|
return FUNC_RET_ERROR;
|
}
|
|
if (adapterInfos != NULL) {
|
memset(adapterInfos, 0, (*adapter_info_size) * sizeof(OsAdapterInfo));
|
}
|
|
/* count the maximum number of interfaces */
|
for (ifa = ifaddr, if_max = 0; ifa != NULL; ifa = ifa->ifa_next, n++) {
|
if (ifa->ifa_addr == NULL) {
|
continue;
|
}
|
if_max++;
|
}
|
|
/* allocate space for names */
|
ifnames = (char*) malloc(NI_MAXHOST * if_max);
|
memset(ifnames, 0, NI_MAXHOST * if_max);
|
/* Walk through linked list, maintaining head pointer so we
|
can free list later */
|
for (ifa = ifaddr, n = 0, if_num = 0; ifa != NULL;
|
ifa = ifa->ifa_next, n++) {
|
if (ifa->ifa_addr == NULL) {
|
continue;
|
}
|
if_name_position = ifname_position(ifnames, ifa->ifa_name, if_num);
|
//interface name not seen en advance
|
if (if_name_position < 0) {
|
strncpy(&ifnames[if_num * NI_MAXHOST], ifa->ifa_name, NI_MAXHOST);
|
if (adapterInfos != NULL && if_num < *adapter_info_size) {
|
strncpy(adapterInfos[if_num].description, ifa->ifa_name,
|
NI_MAXHOST-1);
|
}
|
if_name_position = if_num;
|
if_num++;
|
if (adapterInfos == NULL) {
|
continue;
|
}
|
}
|
family = ifa->ifa_addr->sa_family;
|
/* Display interface name and family (including symbolic
|
form of the latter for the common families) */
|
#ifdef _DEBUG
|
printf("%-8s %s (%d)\n", ifa->ifa_name,
|
(family == AF_PACKET) ? "AF_PACKET" :
|
(family == AF_INET) ? "AF_INET" :
|
(family == AF_INET6) ? "AF_INET6" : "???", family);
|
#endif
|
/* For an AF_INET* interface address, display the address
|
* || family == AF_INET6*/
|
if (family == AF_INET) {
|
/*
|
s = getnameinfo(ifa->ifa_addr,
|
(family == AF_INET) ?
|
sizeof(struct sockaddr_in) :
|
sizeof(struct sockaddr_in6), host, NI_MAXHOST,
|
NULL, 0, NI_NUMERICHOST);
|
|
#ifdef _DEBUG
|
s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host,
|
NI_MAXHOST,
|
NULL, 0, NI_NUMERICHOST);
|
if (s != 0) {
|
printf("getnameinfo() failed: %s\n", gai_strerror(s));
|
}
|
printf("\t\taddress: <%s>\n", host);
|
#endif
|
*/
|
if (adapterInfos != NULL && if_name_position < *adapter_info_size) {
|
struct sockaddr_in *s1 = (struct sockaddr_in*) ifa->ifa_addr;
|
in_addr_t iaddr = s1->sin_addr.s_addr;
|
adapterInfos[if_name_position].ipv4_address[0] = (iaddr
|
& 0x000000ff);
|
adapterInfos[if_name_position].ipv4_address[1] = (iaddr
|
& 0x0000ff00) >> 8;
|
adapterInfos[if_name_position].ipv4_address[2] = (iaddr
|
& 0x00ff0000) >> 16;
|
adapterInfos[if_name_position].ipv4_address[3] = (iaddr
|
& 0xff000000) >> 24;
|
}
|
} else if (family == AF_PACKET && ifa->ifa_data != NULL) {
|
struct sockaddr_ll *s1 = (struct sockaddr_ll*) ifa->ifa_addr;
|
if (adapterInfos != NULL && if_name_position < *adapter_info_size) {
|
int i;
|
for (i = 0; i < 6; i++) {
|
adapterInfos[if_name_position].mac_address[i] =
|
s1->sll_addr[i];
|
#ifdef _DEBUG
|
printf("%02x:", s1->sll_addr[i]);
|
#endif
|
}
|
#ifdef _DEBUG
|
printf("\t %s\n", ifa->ifa_name);
|
#endif
|
|
}
|
}
|
}
|
|
*adapter_info_size = if_num;
|
if (adapterInfos == NULL) {
|
f_return = FUNC_RET_OK;
|
} else if (*adapter_info_size < if_num) {
|
f_return = FUNC_RET_BUFFER_TOO_SMALL;
|
}
|
freeifaddrs(ifaddr);
|
free(ifnames);
|
return f_return;
|
}
|
