mirror of
https://github.com/Waujito/youtubeUnblock.git
synced 2024-12-22 06:15:31 +00:00
Add distinct fragmentation strategies
Fix ip4_frag, implement no fragmentation strategy. Related to #24
This commit is contained in:
Vadim Vetrov
parent
4793f537de
commit
be40bc91e7
153
youtubeUnblock.c
153
youtubeUnblock.c
@ -27,9 +27,18 @@
|
||||
#define USE_GSO
|
||||
#endif
|
||||
|
||||
#ifndef USE_IP_FRAGMENTATION
|
||||
#define USE_TCP_SEGMENTATION
|
||||
#endif
|
||||
#define FRAG_STRAT_TCP 0
|
||||
#define FRAG_STRAT_IP 1
|
||||
#define FRAG_STRAT_NONE 2
|
||||
|
||||
#define FRAGMENTATION_STRATEGY FRAG_STRAT_TCP
|
||||
|
||||
#if FRAGMENTATION_STRATEGY == FRAG_STRAT_TCP
|
||||
#define USE_TCP_SEGMENTATION
|
||||
#elif FRAGMENTATION_STRATEGY == FRAG_STRAT_IP
|
||||
#define USE_IP_FRAGMENTATION
|
||||
#elif FRAGMENTATION_STRATEGY == FRAG_STRAT_NONE
|
||||
#endif
|
||||
|
||||
#define RAWSOCKET_MARK (1 << 15)
|
||||
|
||||
@ -173,12 +182,17 @@ static int ipv4_frag(struct pkt_buff *pktb, size_t payload_offset,
|
||||
uint8_t buff2[MNL_SOCKET_BUFFER_SIZE];
|
||||
|
||||
struct iphdr *hdr = nfq_ip_get_hdr(pktb);
|
||||
if (hdr == NULL) {
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
}
|
||||
|
||||
size_t hdr_len = hdr->ihl * 4;
|
||||
|
||||
uint8_t *payload = pktb_data(pktb) + hdr_len;
|
||||
size_t plen = pktb_len(pktb) - hdr_len;
|
||||
|
||||
if (hdr == NULL || payload == NULL || plen <= payload_offset) {
|
||||
if (payload == NULL || plen <= payload_offset) {
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
}
|
||||
@ -255,15 +269,25 @@ static int tcp4_frag(struct pkt_buff *pktb, size_t payload_offset,
|
||||
struct iphdr *hdr = nfq_ip_get_hdr(pktb);
|
||||
size_t hdr_len = hdr->ihl * 4;
|
||||
if (hdr == NULL) {
|
||||
errno = EINVAL;
|
||||
perror("tcp4_frag: nfq_ip_get_hdr is null\n");
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
}
|
||||
if (hdr->protocol != IPPROTO_TCP || !(ntohs(hdr->frag_off) & IP_DF)) {
|
||||
perror("tcp4_frag: proto is tcp or request is fragmented");
|
||||
if (hdr->protocol != IPPROTO_TCP) {
|
||||
errno = EINVAL;
|
||||
perror("tcp4_frag: proto is not tcp");
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
}
|
||||
if (!(ntohs(hdr->frag_off) & IP_DF)) {
|
||||
errno = EINVAL;
|
||||
perror("tcp4_frag: request is ip-fragmented");
|
||||
fprintf(stderr, "tcp4_frag: frag_off: %04x\n", ntohs(hdr->frag_off));
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
}
|
||||
|
||||
|
||||
if (nfq_ip_set_transport_header(pktb, hdr)) {
|
||||
perror("tcp4_frag: ip_set_transport_header");
|
||||
@ -274,6 +298,7 @@ static int tcp4_frag(struct pkt_buff *pktb, size_t payload_offset,
|
||||
struct tcphdr *tcph = nfq_tcp_get_hdr(pktb);
|
||||
size_t tcph_len = tcph->doff * 4;
|
||||
if (tcph == NULL) {
|
||||
errno = EINVAL;
|
||||
perror("tcp4_frag: tcph is NULL");
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
@ -283,6 +308,7 @@ static int tcp4_frag(struct pkt_buff *pktb, size_t payload_offset,
|
||||
size_t plen = nfq_tcp_get_payload_len(tcph, pktb);
|
||||
|
||||
if (payload == NULL || plen <= payload_offset) {
|
||||
errno = EINVAL;
|
||||
perror("tcp4_frag: payload is too small or NULL");
|
||||
errno = EINVAL;
|
||||
return -1;
|
||||
@ -352,13 +378,18 @@ static int send_raw_socket(struct pkt_buff *pktb) {
|
||||
struct pkt_buff *buff1;
|
||||
struct pkt_buff *buff2;
|
||||
|
||||
#ifdef USE_TCP_SEGMENTATION
|
||||
#if defined(USE_TCP_SEGMENTATION) || defined(RAWSOCK_TCP_FSTRAT)
|
||||
if (tcp4_frag(pktb, AVAILABLE_MTU-128, &buff1, &buff2) < 0)
|
||||
return -1;
|
||||
#else
|
||||
#elif defined(USE_IP_FRAGMENTATION) || defined(RAWSOCK_IP_FSTRAT)
|
||||
if (ipv4_frag(pktb, AVAILABLE_MTU-128, &buff1, &buff2) < 0)
|
||||
return -1;
|
||||
|
||||
#else
|
||||
errno = EINVAL;
|
||||
printf("send_raw_socket: Packet is too big but fragmentation is disabled! "
|
||||
"Pass -DRAWSOCK_TCP_FSTRAT or -DRAWSOCK_IP_FSTRAT as CFLAGS "
|
||||
"To enable it only for raw socket\n");
|
||||
return -1;
|
||||
#endif
|
||||
|
||||
int sent = 0;
|
||||
@ -452,8 +483,6 @@ static int fallback_accept_packet(uint32_t id) {
|
||||
const char googlevideo_ending[] = "googlevideo.com";
|
||||
const int googlevideo_len = 15;
|
||||
|
||||
#define GOOGLEVIDEO_MARK 0xfc74
|
||||
|
||||
struct verdict {
|
||||
int gvideo_hello; /* google video hello packet */
|
||||
int sni_offset; /* offset from start of tcp _payload_ */
|
||||
@ -718,10 +747,9 @@ static int process_packet(const struct packet_data packet) {
|
||||
struct pkt_buff *frag1;
|
||||
struct pkt_buff *frag2;
|
||||
nfq_nlmsg_verdict_put(verdnlh, packet.id, NF_DROP);
|
||||
|
||||
|
||||
#ifdef USE_TCP_SEGMENTATION
|
||||
int ret = 0;
|
||||
|
||||
|
||||
#ifdef FAKE_SNI
|
||||
struct pkt_buff *fake_sni = gen_fake_sni(ip_header, tcph);
|
||||
if (fake_sni == NULL) {
|
||||
@ -736,15 +764,13 @@ static int process_packet(const struct packet_data packet) {
|
||||
goto fallback;
|
||||
}
|
||||
#endif
|
||||
|
||||
size_t ipd_offset = vrd.sni_offset;
|
||||
size_t mid_offset = ipd_offset + vrd.sni_len / 2;
|
||||
|
||||
struct pkt_buff *pktb = pktb_alloc(
|
||||
family,
|
||||
packet.payload,
|
||||
packet.payload_len,
|
||||
0);
|
||||
0);
|
||||
|
||||
|
||||
|
||||
if (pktb == NULL) {
|
||||
perror("pktb_alloc of payload");
|
||||
@ -753,23 +779,55 @@ static int process_packet(const struct packet_data packet) {
|
||||
#endif
|
||||
goto fallback;
|
||||
}
|
||||
|
||||
|
||||
struct iphdr *piph = nfq_ip_get_hdr(pktb);
|
||||
ret = nfq_ip_set_transport_header(pktb, piph);
|
||||
struct tcphdr *ptcph = nfq_tcp_get_hdr(pktb);
|
||||
if (!piph || ret < 0 || !ptcph) {
|
||||
perror("cannot parse pktb");
|
||||
goto gv_free;
|
||||
}
|
||||
|
||||
nfq_ip_set_checksum(piph);
|
||||
nfq_tcp_compute_checksum_ipv4(ptcph, piph);
|
||||
|
||||
#if defined(USE_TCP_SEGMENTATION)
|
||||
size_t ipd_offset = vrd.sni_offset;
|
||||
size_t mid_offset = ipd_offset + vrd.sni_len / 2;
|
||||
|
||||
|
||||
if (tcp4_frag(pktb, mid_offset, &frag1, &frag2) < 0) {
|
||||
perror("tcp4_frag");
|
||||
pktb_free(pktb);
|
||||
#ifdef FAKE_SNI
|
||||
pktb_free(fake_sni);
|
||||
#endif
|
||||
|
||||
goto fallback;
|
||||
|
||||
goto gv_free;
|
||||
}
|
||||
|
||||
#elif defined(USE_IP_FRAGMENTATION)
|
||||
size_t ipd_offset = ((char *)data - (char *)tcph) + vrd.sni_offset;
|
||||
size_t mid_offset = ipd_offset + vrd.sni_len / 2;
|
||||
mid_offset += 8 - mid_offset % 8;
|
||||
|
||||
if (ipv4_frag(pktb, mid_offset, &frag1, &frag2) < 0) {
|
||||
perror("ipv4_frag");
|
||||
|
||||
goto gv_free;
|
||||
}
|
||||
|
||||
#else
|
||||
ret = send_raw_socket(pktb);
|
||||
if (ret < 0) {
|
||||
perror("raw pack send");
|
||||
}
|
||||
goto gv_free;
|
||||
#endif
|
||||
|
||||
ret = send_raw_socket(frag2);
|
||||
if (ret < 0) {
|
||||
errno = ret;
|
||||
perror("raw frags send: frag2");
|
||||
pktb_free(frag1);
|
||||
goto err;
|
||||
|
||||
goto free_frags;
|
||||
}
|
||||
|
||||
#ifdef SEG2_DELAY
|
||||
@ -782,45 +840,22 @@ static int process_packet(const struct packet_data packet) {
|
||||
#else
|
||||
ret = send_raw_socket(frag1);
|
||||
if (ret < 0) {
|
||||
errno = ret;
|
||||
perror("raw frags send: frag1");
|
||||
pktb_free(frag1);
|
||||
goto err;
|
||||
|
||||
goto free_frags;
|
||||
}
|
||||
|
||||
pktb_free(frag1);
|
||||
#endif
|
||||
err:
|
||||
|
||||
free_frags:
|
||||
pktb_free(frag2);
|
||||
gv_free:
|
||||
pktb_free(pktb);
|
||||
#ifdef FAKE_SNI
|
||||
pktb_free(fake_sni);
|
||||
#endif
|
||||
|
||||
#else
|
||||
// TODO: Implement compute of tcp checksum
|
||||
// GSO may turn kernel to not compute the tcp checksum.
|
||||
// Also it will never be meaningless to ensure the
|
||||
// checksum is right.
|
||||
// nfq_tcp_compute_checksum_ipv4(tcph, ip_header);
|
||||
|
||||
size_t ipd_offset = ((char *)data - (char *)tcph) + vrd.sni_offset;
|
||||
size_t mid_offset = ipd_offset + vrd.sni_len / 2;
|
||||
mid_offset += 8 - mid_offset % 8;
|
||||
|
||||
|
||||
if (ipv4_frag(pktb, mid_offset, &frag1, &frag2) < 0) {
|
||||
perror("ipv4_frag");
|
||||
goto fallback;
|
||||
}
|
||||
|
||||
if ((send_raw_socket(frag1) == -1) || (send_raw_socket(frag2) == -1)) {
|
||||
perror("raw frags send");
|
||||
}
|
||||
|
||||
pktb_free(frag1);
|
||||
pktb_free(frag2);
|
||||
#endif
|
||||
|
||||
}
|
||||
|
||||
|
||||
@ -897,10 +932,12 @@ int main(int argc, const char *argv[])
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
||||
#ifdef USE_TCP_SEGMENTATION
|
||||
#if defined(USE_TCP_SEGMENTATION)
|
||||
printf("Using TCP segmentation\n");
|
||||
#else
|
||||
#elif defined(USE_IP_FRAGMENTATION)
|
||||
printf("Using IP fragmentation\n");
|
||||
#else
|
||||
printf("SNI fragmentation is disabled\n");
|
||||
#endif
|
||||
|
||||
#ifdef SEG2_DELAY
|
||||
|
||||
Loading…
Reference in New Issue
Block a user