src/common/mac.c
/* $Id$ */
/*
* Copyright (c) 2001-2010 Aaron Turner <aturner at synfin dot net>
* Copyright (c) 2013-2022 Fred Klassen <tcpreplay at appneta dot com> - AppNeta
*
* The Tcpreplay Suite of tools 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 3 of the
* License, or with the authors permission any later version.
*
* The Tcpreplay Suite is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the Tcpreplay Suite. If not, see <http://www.gnu.org/licenses/>.
*/
#include "mac.h"
#include "config.h"
#include "common.h"
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
/**
* converts a string representation of a MAC address, based on
* non-portable ether_aton()
*/
void
mac2hex(const char *mac, u_char *dst, int len)
{
int i;
char *pp;
if (len < 6)
return;
while (isspace(*mac))
mac++;
/* expect 6 hex octets separated by ':' or space/NUL if last octet */
for (i = 0; i < 6; i++) {
long l = strtol(mac, &pp, 16);
if (pp == mac || l > 0xFF || l < 0)
return;
if (!(*pp == ':' || (i == 5 && (isspace(*pp) || *pp == '\0'))))
return;
dst[i] = (u_char)l;
mac = pp + 1;
}
}
/**
* converts a string representation of TWO MAC addresses, which
* are comma deliminated into two hex values. Either *first or *second
* can be NULL if there is nothing before or after the comma.
* returns:
* 1 = first mac
* 2 = second mac
* 3 = both mac's
* 0 = none
*/
int
dualmac2hex(const char *dualmac, u_char *first, u_char *second, int len)
{
char *tok = NULL, *temp, *string;
int ret = 0;
string = safe_strdup(dualmac);
/* if we've only got a comma, then return NULL's */
if (len <= 1)
goto done;
temp = strtok_r(string, ",", &tok);
if (strlen(temp)) {
mac2hex(temp, first, len);
ret = 1;
}
temp = strtok_r(NULL, ",", &tok);
/* temp is null if no comma */
if (temp != NULL) {
if (strlen(temp)) {
mac2hex(temp, second, len);
ret += 2;
}
}
done:
safe_free(string);
return ret;
}
/**
* Figures out if a MAC is listed in a comma delimited
* string of MAC addresses.
* returns TCPR_DIR_C2S if listed
* returns TCPR_DIR_S2C if not listed
*/
tcpr_dir_t
macinstring(const char *macstring, const u_char *mac)
{
char *tok = NULL, *tempstr, *ourstring;
u_char tempmac[6];
int len = 6, ret = TCPR_DIR_S2C;
ourstring = safe_strdup(macstring);
memset(&tempmac[0], 0, sizeof(tempmac));
tempstr = strtok_r(ourstring, ",", &tok);
if (tempstr != NULL && strlen(tempstr)) {
mac2hex(tempstr, tempmac, len);
if (memcmp(mac, tempmac, len) == 0) {
dbgx(3, "Packet matches: " MAC_FORMAT " sending out primary.\n", MAC_STR(tempmac));
ret = TCPR_DIR_C2S;
goto EXIT_MACINSTRING;
}
} else {
goto EXIT_MACINSTRING;
}
while ((tempstr = strtok_r(NULL, ",", &tok)) != NULL) {
mac2hex(tempstr, tempmac, len);
if (memcmp(mac, tempmac, len) == 0) {
ret = TCPR_DIR_C2S;
dbgx(3, "Packet matches: " MAC_FORMAT " sending out primary.\n", MAC_STR(tempmac));
goto EXIT_MACINSTRING;
}
}
EXIT_MACINSTRING:
safe_free(ourstring);
#ifdef DEBUG
if (ret == TCPR_DIR_S2C)
dbg(3, "Packet doesn't match any MAC addresses sending out secondary.\n");
#endif
return ret;
}