Use the already correctly determined transport header offset instead of
assuming that the packet is IPv4.
Signed-off-by: Aaron Thompson <dev@xxxxxxxxxx>
---
src/helpers/ssdp.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/src/helpers/ssdp.c b/src/helpers/ssdp.c
index 56526f4..0c6f563 100644
--- a/src/helpers/ssdp.c
+++ b/src/helpers/ssdp.c
@@ -48,7 +48,6 @@
#include <errno.h>
#include <stdlib.h>
#include <arpa/inet.h>
-#include <netinet/ip.h>
#define _GNU_SOURCE
#include <netinet/tcp.h>
#include <netinet/udp.h>
@@ -159,11 +158,9 @@ static int handle_ssdp_new(struct pkt_buff *pkt, uint32_t protoff,
{
int ret = NF_ACCEPT;
union nfct_attr_grp_addr daddr, saddr, taddr;
- struct iphdr *net_hdr = (struct iphdr *)pktb_network_header(pkt);
int good_packet = 0;
struct nf_expect *exp;
uint16_t port;
- unsigned int dataoff;
void *sb_ptr;
cthelper_get_addr_dst(myct->ct, MYCT_DIR_ORIG, &daddr);
@@ -201,13 +198,12 @@ static int handle_ssdp_new(struct pkt_buff *pkt, uint32_t protoff,
}
/* No data? Ignore */
- dataoff = net_hdr->ihl*4 + sizeof(struct udphdr);
- if (dataoff >= pktb_len(pkt)) {
+ if (protoff + sizeof(struct udphdr) >= pktb_len(pkt)) {
pr_debug("ssdp_help: UDP payload too small for M-SEARCH; ignoring\n");
return NF_ACCEPT;
}
- sb_ptr = pktb_network_header(pkt) + dataoff;
+ sb_ptr = pktb_network_header(pkt) + protoff + sizeof(struct udphdr);
if (memcmp(sb_ptr, SSDP_M_SEARCH, SSDP_M_SEARCH_SIZE) != 0) {
pr_debug("ssdp_help: UDP payload does not begin with 'M-SEARCH'; ignoring\n");
--
2.30.2
