hostap/wlantest/rx_ip.c

148 lines
3.7 KiB
C

/*
* Received Data frame processing for IPv4 packets
* Copyright (c) 2010, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "utils/includes.h"
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include "utils/common.h"
#include "wlantest.h"
static void rx_data_icmp(struct wlantest *wt, const u8 *bssid,
const u8 *sta_addr, u32 dst, u32 src,
const u8 *data, size_t len)
{
struct in_addr addr;
char buf[20];
const struct icmphdr *hdr;
u16 id, seq;
struct wlantest_bss *bss;
struct wlantest_sta *sta;
hdr = (const struct icmphdr *) data;
if (len < 4)
return;
/* TODO: check hdr->checksum */
if (hdr->type != ICMP_ECHOREPLY && hdr->type != ICMP_ECHO)
return;
if (len < 8)
return;
id = ntohs(hdr->un.echo.id);
seq = ntohs(hdr->un.echo.sequence);
addr.s_addr = dst;
snprintf(buf, sizeof(buf), "%s", inet_ntoa(addr));
addr.s_addr = src;
wpa_printf(MSG_DEBUG, "ICMP echo %s %s -> %s id=%04x seq=%u len=%u",
hdr->type == ICMP_ECHO ? "request" : "response",
inet_ntoa(addr), buf, id, seq, (unsigned) len - 8);
bss = bss_find(wt, bssid);
if (bss == NULL) {
wpa_printf(MSG_INFO, "No BSS " MACSTR " known for ICMP packet",
MAC2STR(bssid));
return;
}
if (sta_addr == NULL)
return; /* FromDS broadcast ping */
sta = sta_find(bss, sta_addr);
if (sta == NULL) {
wpa_printf(MSG_INFO, "No STA " MACSTR " known for ICMP packet",
MAC2STR(sta_addr));
return;
}
if (hdr->type == ICMP_ECHO) {
sta->icmp_echo_req_src = src;
sta->icmp_echo_req_dst = dst;
sta->icmp_echo_req_id = id;
sta->icmp_echo_req_seq = seq;
return;
}
if (sta->icmp_echo_req_src == dst &&
sta->icmp_echo_req_dst == src &&
sta->icmp_echo_req_id == id &&
sta->icmp_echo_req_seq == seq) {
sta->counters[WLANTEST_STA_COUNTER_PING_OK]++;
wpa_printf(MSG_DEBUG, "ICMP echo (ping) match for STA " MACSTR,
MAC2STR(sta->addr));
}
}
void rx_data_ip(struct wlantest *wt, const u8 *bssid, const u8 *sta_addr,
const u8 *dst, const u8 *src, const u8 *data, size_t len)
{
const struct iphdr *ip;
const u8 *payload;
size_t plen;
u16 frag_off, tot_len;
ip = (const struct iphdr *) data;
if (len < sizeof(*ip))
return;
if (ip->version != 4) {
wpa_printf(MSG_DEBUG, "Unexpected IP protocol version %u in "
"IPv4 packet (bssid=" MACSTR " str=" MACSTR
" dst=" MACSTR ")", ip->version, MAC2STR(bssid),
MAC2STR(src), MAC2STR(dst));
return;
}
if (ip->ihl * 4 < sizeof(*ip)) {
wpa_printf(MSG_DEBUG, "Unexpected IP header length %u in "
"IPv4 packet (bssid=" MACSTR " str=" MACSTR
" dst=" MACSTR ")", ip->ihl, MAC2STR(bssid),
MAC2STR(src), MAC2STR(dst));
return;
}
if (ip->ihl * 4 > len) {
wpa_printf(MSG_DEBUG, "Truncated IP header (ihl=%u len=%u) in "
"IPv4 packet (bssid=" MACSTR " str=" MACSTR
" dst=" MACSTR ")", ip->ihl, (unsigned) len,
MAC2STR(bssid), MAC2STR(src), MAC2STR(dst));
return;
}
/* TODO: check header checksum in ip->check */
frag_off = be_to_host16(ip->frag_off);
if (frag_off & 0x1fff) {
wpa_printf(MSG_EXCESSIVE, "IP fragment reassembly not yet "
"supported");
return;
}
tot_len = be_to_host16(ip->tot_len);
if (tot_len > len)
return;
if (tot_len < len)
len = tot_len;
payload = data + 4 * ip->ihl;
plen = len - 4 * ip->ihl;
switch (ip->protocol) {
case IPPROTO_ICMP:
rx_data_icmp(wt, bssid, sta_addr, ip->daddr, ip->saddr,
payload, plen);
break;
}
}