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Search for HTTP methods in fragmented packets with Window Size 1 or 2. Fixes #30.

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ValdikSS 2017-08-28 11:43:55 +03:00
parent 00e4964e73
commit ee665ee3bd
1 changed files with 16 additions and 5 deletions
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19
goodbyedpi.c
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@ -130,12 +130,20 @@ static void change_window_size(const char *pkt, int size) {
}
/* HTTP method end without trailing space */
static PVOID find_http_method_end(const char *pkt) {
static PVOID find_http_method_end(const char *pkt, int offset) {
int i;
for (i = 0; i<(sizeof(http_methods) / sizeof(*http_methods)); i++) {
if (memcmp(pkt, http_methods[i], strlen(http_methods[i])) == 0) {
return (char*)pkt + strlen(http_methods[i]) - 1;
}
/* Try to find HTTP method in a second part of fragmented packet */
if ((offset == 1 || offset == 2) &&
memcmp(pkt, http_methods[i] + offset,
strlen(http_methods[i]) - offset) == 0
)
{
return (char*)pkt + strlen(http_methods[i]) - offset - 1;
}
}
return NULL;
}
@ -304,8 +312,10 @@ int main(int argc, char *argv[]) {
/* Handle OUTBOUND packet, search for Host header */
else if (addr.Direction == WINDIVERT_DIRECTION_OUTBOUND &&
packet_dataLen > 16 && ppTcpHdr->DstPort == htons(80) &&
find_http_method_end(packet_data) &&
(do_host || do_host_removespace)) {
find_http_method_end(packet_data,
(do_fragment_http ? http_fragment_size : 0)) &&
(do_host || do_host_removespace))
{
data_addr = find_host_header(packet_data, packet_dataLen);
if (data_addr) {
@ -319,7 +329,8 @@ int main(int argc, char *argv[]) {
if (do_additional_space && do_host_removespace) {
/* End of "Host:" without trailing space */
host_addr = data_addr + strlen(http_host_find) - 1;
method_addr = find_http_method_end(packet_data);
method_addr = find_http_method_end(packet_data,
(do_fragment_http ? http_fragment_size : 0));
if (method_addr) {
memmove(method_addr + 1, method_addr, (PVOID)host_addr - (PVOID)method_addr);