dvtws: set ip_id field in generated packets

This commit is contained in:
bol-van 2024-11-15 15:51:59 +03:00
parent 5d6c91f7e9
commit 677feecada
3 changed files with 114 additions and 69 deletions

View File

@ -163,7 +163,7 @@ static void fill_udphdr(struct udphdr *udp, uint16_t nsport, uint16_t ndport, ui
udp->uh_sum = 0;
}
static void fill_iphdr(struct ip *ip, const struct in_addr *src, const struct in_addr *dst, uint16_t pktlen, uint8_t proto, uint8_t ttl, uint8_t tos)
static void fill_iphdr(struct ip *ip, const struct in_addr *src, const struct in_addr *dst, uint16_t pktlen, uint8_t proto, uint8_t ttl, uint8_t tos, uint16_t ip_id)
{
ip->ip_tos = tos;
ip->ip_sum = 0;
@ -171,7 +171,7 @@ static void fill_iphdr(struct ip *ip, const struct in_addr *src, const struct in
ip->ip_v = 4;
ip->ip_hl = 5;
ip->ip_len = htons(pktlen);
ip->ip_id = 0;
ip->ip_id = ip_id;
ip->ip_ttl = ttl;
ip->ip_p = proto;
ip->ip_src = *src;
@ -196,6 +196,7 @@ bool prepare_tcp_segment4(
uint32_t *timestamps,
uint8_t ttl,
uint8_t tos,
uint16_t ip_id,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
@ -211,7 +212,7 @@ bool prepare_tcp_segment4(
struct tcphdr *tcp = (struct tcphdr*)(ip+1);
uint8_t *payload = (uint8_t*)(tcp+1)+tcpoptlen;
fill_iphdr(ip, &src->sin_addr, &dst->sin_addr, pktlen, IPPROTO_TCP, ttl, tos);
fill_iphdr(ip, &src->sin_addr, &dst->sin_addr, pktlen, IPPROTO_TCP, ttl, tos, ip_id);
fill_tcphdr(tcp,fooling,tcp_flags,nseq,nack_seq,src->sin_port,dst->sin_port,nwsize,scale_factor,timestamps,badseq_increment,badseq_ack_increment,len);
memcpy(payload,data,len);
@ -314,7 +315,9 @@ bool prepare_tcp_segment(
uint8_t scale_factor,
uint32_t *timestamps,
uint8_t ttl,
uint8_t tos, uint32_t flow_label,
uint8_t tos,
uint16_t ip_id,
uint32_t flow_label,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
@ -322,7 +325,7 @@ bool prepare_tcp_segment(
uint8_t *buf, size_t *buflen)
{
return (src->sa_family==AF_INET && dst->sa_family==AF_INET) ?
prepare_tcp_segment4((struct sockaddr_in *)src,(struct sockaddr_in *)dst,tcp_flags,nseq,nack_seq,nwsize,scale_factor,timestamps,ttl,tos,fooling,badseq_increment,badseq_ack_increment,data,len,buf,buflen) :
prepare_tcp_segment4((struct sockaddr_in *)src,(struct sockaddr_in *)dst,tcp_flags,nseq,nack_seq,nwsize,scale_factor,timestamps,ttl,tos,ip_id,fooling,badseq_increment,badseq_ack_increment,data,len,buf,buflen) :
(src->sa_family==AF_INET6 && dst->sa_family==AF_INET6) ?
prepare_tcp_segment6((struct sockaddr_in6 *)src,(struct sockaddr_in6 *)dst,tcp_flags,nseq,nack_seq,nwsize,scale_factor,timestamps,ttl,flow_label,fooling,badseq_increment,badseq_ack_increment,data,len,buf,buflen) :
false;
@ -334,6 +337,7 @@ bool prepare_udp_segment4(
const struct sockaddr_in *src, const struct sockaddr_in *dst,
uint8_t ttl,
uint8_t tos,
uint16_t ip_id,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,
@ -357,7 +361,7 @@ bool prepare_udp_segment4(
uint8_t *payload = (uint8_t*)(udp+1);
fill_iphdr(ip, &src->sin_addr, &dst->sin_addr, pktlen, IPPROTO_UDP, ttl, tos);
fill_iphdr(ip, &src->sin_addr, &dst->sin_addr, pktlen, IPPROTO_UDP, ttl, tos, ip_id);
fill_udphdr(udp, src->sin_port, dst->sin_port, datalen);
memcpy(payload,data,len);
@ -463,7 +467,9 @@ bool prepare_udp_segment6(
bool prepare_udp_segment(
const struct sockaddr *src, const struct sockaddr *dst,
uint8_t ttl,
uint8_t tos, uint32_t flow_label,
uint8_t tos,
uint16_t ip_id,
uint32_t flow_label,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,
@ -471,7 +477,7 @@ bool prepare_udp_segment(
uint8_t *buf, size_t *buflen)
{
return (src->sa_family==AF_INET && dst->sa_family==AF_INET) ?
prepare_udp_segment4((struct sockaddr_in *)src,(struct sockaddr_in *)dst,ttl,tos,fooling,padding,padding_size,padlen,data,len,buf,buflen) :
prepare_udp_segment4((struct sockaddr_in *)src,(struct sockaddr_in *)dst,ttl,tos,ip_id,fooling,padding,padding_size,padlen,data,len,buf,buflen) :
(src->sa_family==AF_INET6 && dst->sa_family==AF_INET6) ?
prepare_udp_segment6((struct sockaddr_in6 *)src,(struct sockaddr_in6 *)dst,ttl,flow_label,fooling,padding,padding_size,padlen,data,len,buf,buflen) :
false;

View File

@ -61,6 +61,7 @@ uint32_t net16_add(uint16_t netorder_value, uint16_t cpuorder_increment);
#define VERDICT_NOCSUM 4
#define IP4_TOS(ip_header) (ip_header ? ip_header->ip_tos : 0)
#define IP4_IP_ID(ip_header) (ip_header ? ip_header->ip_id : 0)
#define IP6_FLOW(ip6_header) (ip6_header ? ip6_header->ip6_ctlun.ip6_un1.ip6_un1_flow : 0)
// seq and wsize have network byte order
@ -73,6 +74,7 @@ bool prepare_tcp_segment4(
uint32_t *timestamps,
uint8_t ttl,
uint8_t tos,
uint16_t ip_id,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
@ -100,7 +102,9 @@ bool prepare_tcp_segment(
uint8_t scale_factor,
uint32_t *timestamps,
uint8_t ttl,
uint8_t tos, uint32_t flow_label,
uint8_t tos,
uint16_t ip_id,
uint32_t flow_label,
uint32_t fooling,
uint32_t badseq_increment,
uint32_t badseq_ack_increment,
@ -112,6 +116,7 @@ bool prepare_udp_segment4(
const struct sockaddr_in *src, const struct sockaddr_in *dst,
uint8_t ttl,
uint8_t tos,
uint16_t ip_id,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,
@ -129,7 +134,9 @@ bool prepare_udp_segment6(
bool prepare_udp_segment(
const struct sockaddr *src, const struct sockaddr *dst,
uint8_t ttl,
uint8_t tos, uint32_t flow_label,
uint8_t tos,
uint16_t ip_id,
uint32_t flow_label,
uint32_t fooling,
const uint8_t *padding, size_t padding_size,
int padlen,

View File

@ -603,6 +603,22 @@ static void autottl_discover(t_ctrack *ctrack, bool bIpv6)
}
}
#ifdef BSD
// BSD pass to divert socket ip_id=0 and does not auto set it if sent via divert socket
static uint16_t IP4_IP_ID_FIX(const struct ip *ip)
{
return ip ? ip->ip_id ? ip->ip_id : (uint16_t)random() : 0;
}
#define IP4_IP_ID_NEXT(ip_id) net16_add(ip_id,+1)
#define IP4_IP_ID_PREV(ip_id) net16_add(ip_id,-1)
#else
// in linux kernel sets increasing ip_id if it's zero
#define IP4_IP_ID_FIX(x) 0
#define IP4_IP_ID_NEXT(ip_id) ip_id
#define IP4_IP_ID_PREV(ip_id) ip_id
#endif
static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint32_t fwmark, const char *ifout, struct dissect *dis)
{
uint8_t verdict=VERDICT_PASS;
@ -787,7 +803,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
case DESYNC_SYNACK:
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, TH_SYN|TH_ACK, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_fake,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_fake,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6),
dp->desync_fooling_mode,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
NULL, 0, pkt1, &pkt1_len))
{
@ -811,7 +827,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
}
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_orig,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6),
0,0,0, dp->fake_syndata,dp->fake_syndata_size, pkt1,&pkt1_len))
{
return verdict;
@ -844,6 +860,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
size_t multisplit_pos[MAX_SPLITS];
int multisplit_count;
int i;
uint16_t ip_id;
t_l7proto l7proto = UNKNOWN;
if (replay)
@ -1216,7 +1233,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
case DESYNC_FAKE:
if (reasm_offset) break;
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_fake,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_fake,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6),
dp->desync_fooling_mode,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
fake, fake_size, pkt1, &pkt1_len))
{
@ -1230,7 +1247,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
case DESYNC_RSTACK:
if (reasm_offset) break;
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, TH_RST | (dp->desync_mode==DESYNC_RSTACK ? TH_ACK:0), dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_fake,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_fake,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6),
dp->desync_fooling_mode,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
NULL, 0, pkt1, &pkt1_len))
{
@ -1248,7 +1265,7 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
(!multisplit_count && (dp->desync_mode2==DESYNC_MULTISPLIT || dp->desync_mode2==DESYNC_MULTIDISORDER))))
{
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_orig,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6),
fooling_orig,0,0,
dis->data_payload, dis->len_payload, pkt1, &pkt1_len))
{
@ -1280,6 +1297,9 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
uint8_t ovlseg[DPI_DESYNC_MAX_FAKE_LEN+100], *seg;
size_t seg_len,from,to;
unsigned int seqovl;
ip_id = IP4_IP_ID_FIX(dis->ip);
for (i=0,from=0 ; i<=multisplit_count ; i++)
{
to = i==multisplit_count ? dis->len_payload : multisplit_pos[i];
@ -1315,10 +1335,11 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig,
net32_add(dis->tcp->th_seq,from-seqovl), dis->tcp->th_ack,
dis->tcp->th_win, scale_factor, timestamps,ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
dis->tcp->th_win, scale_factor, timestamps,ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
fooling_orig,0,0,
seg, seg_len, pkt1, &pkt1_len))
return verdict;
ip_id=IP4_IP_ID_NEXT(ip_id);
DLOG("sending multisplit part %d %zu-%zu len=%zu seqovl=%u : ",i+1,from,to-1,to-from,seqovl);
hexdump_limited_dlog(seg,seg_len,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
@ -1348,6 +1369,9 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
uint8_t ovlseg[DPI_DESYNC_MAX_FAKE_LEN+100], *seg;
size_t seg_len,from,to;
unsigned int seqovl;
ip_id = IP4_IP_ID_FIX(dis->ip);
for (i=multisplit_count-1,to=dis->len_payload ; i>=-1 ; i--)
{
from = i>=0 ? multisplit_pos[i] : 0;
@ -1380,10 +1404,11 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig,
net32_add(dis->tcp->th_seq,from-seqovl), dis->tcp->th_ack,
dis->tcp->th_win, scale_factor, timestamps,ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
dis->tcp->th_win, scale_factor, timestamps,ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
fooling_orig,0,0,
seg, seg_len, pkt1, &pkt1_len))
return verdict;
ip_id=IP4_IP_ID_PREV(ip_id);
DLOG("sending multisplit part %d %zu-%zu len=%zu seqovl=%u : ",i+2,from,to-1,to-from,seqovl);
hexdump_limited_dlog(seg,seg_len,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
@ -1401,6 +1426,8 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
size_t seg_len;
unsigned int seqovl;
ip_id = IP4_IP_ID_FIX(dis->ip);
if (seqovl_pos>=split_pos)
{
DLOG("seqovl>=split_pos (%u>=%zu). cancelling seqovl.\n",seqovl_pos,split_pos);
@ -1409,44 +1436,42 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
else
seqovl = seqovl_pos;
if (split_pos<dis->len_payload)
if (seqovl)
{
if (seqovl)
seg_len = dis->len_payload-split_pos+seqovl;
if (seg_len>sizeof(fakeseg))
{
seg_len = dis->len_payload-split_pos+seqovl;
if (seg_len>sizeof(fakeseg))
{
DLOG("seqovl is too large\n");
return verdict;
}
fill_pattern(fakeseg,seqovl,dp->seqovl_pattern,sizeof(dp->seqovl_pattern));
memcpy(fakeseg+seqovl,dis->data_payload+split_pos,dis->len_payload-split_pos);
seg = fakeseg;
}
else
{
seg = dis->data_payload+split_pos;
seg_len = dis->len_payload-split_pos;
}
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, net32_add(dis->tcp->th_seq , split_pos - seqovl), dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
fooling_orig,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
seg, seg_len, pkt1, &pkt1_len))
return verdict;
DLOG("sending 2nd out-of-order tcp segment %zu-%zu len=%zu seqovl=%u : ",split_pos,dis->len_payload-1, dis->len_payload-split_pos, seqovl);
hexdump_limited_dlog(seg,seg_len,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
DLOG("seqovl is too large\n");
return verdict;
}
fill_pattern(fakeseg,seqovl,dp->seqovl_pattern,sizeof(dp->seqovl_pattern));
memcpy(fakeseg+seqovl,dis->data_payload+split_pos,dis->len_payload-split_pos);
seg = fakeseg;
}
else
{
seg = dis->data_payload+split_pos;
seg_len = dis->len_payload-split_pos;
}
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, net32_add(dis->tcp->th_seq , split_pos - seqovl), dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
fooling_orig,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
seg, seg_len, pkt1, &pkt1_len))
return verdict;
ip_id=IP4_IP_ID_PREV(ip_id);
DLOG("sending 2nd out-of-order tcp segment %zu-%zu len=%zu seqovl=%u : ",split_pos,dis->len_payload-1, dis->len_payload-split_pos, seqovl);
hexdump_limited_dlog(seg,seg_len,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
return verdict;
seg_len = sizeof(fakeseg);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_fake,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_fake,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
dp->desync_fooling_mode,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
zeropkt, split_pos, fakeseg, &seg_len))
return verdict;
ip_id=IP4_IP_ID_PREV(ip_id);
DLOG("sending fake(1) 1st out-of-order tcp segment 0-%zu len=%zu : ",split_pos-1, split_pos);
hexdump_limited_dlog(zeropkt,split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend_rep(dp->desync_repeats,(struct sockaddr *)&dst, desync_fwmark, ifout , fakeseg, seg_len))
@ -1454,15 +1479,17 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
fooling_orig,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
dis->data_payload, split_pos, pkt1, &pkt1_len))
return verdict;
ip_id=IP4_IP_ID_PREV(ip_id);
DLOG("sending 1st out-of-order tcp segment 0-%zu len=%zu : ",split_pos-1, split_pos);
hexdump_limited_dlog(dis->data_payload,split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
return verdict;
if (dis->ip) ((struct ip*)fakeseg)->ip_id = ip_id;
DLOG("sending fake(2) 1st out-of-order tcp segment 0-%zu len=%zu : ",split_pos-1, split_pos);
hexdump_limited_dlog(zeropkt,split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend_rep(dp->desync_repeats,(struct sockaddr *)&dst, desync_fwmark, ifout , fakeseg, seg_len))
@ -1477,12 +1504,15 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
uint8_t fakeseg[DPI_DESYNC_MAX_FAKE_LEN+100],ovlseg[DPI_DESYNC_MAX_FAKE_LEN+100], *seg;
size_t fakeseg_len,seg_len;
ip_id = IP4_IP_ID_FIX(dis->ip);
fakeseg_len = sizeof(fakeseg);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, dis->tcp->th_seq, dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_fake,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_fake,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
dp->desync_fooling_mode,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
zeropkt, split_pos, fakeseg, &fakeseg_len))
return verdict;
ip_id=IP4_IP_ID_NEXT(ip_id);
DLOG("sending fake(1) 1st tcp segment 0-%zu len=%zu : ",split_pos-1, split_pos);
hexdump_limited_dlog(zeropkt,split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend_rep(dp->desync_repeats,(struct sockaddr *)&dst, desync_fwmark, ifout , fakeseg, fakeseg_len))
@ -1514,10 +1544,11 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, net32_add(dis->tcp->th_seq,-seqovl), dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
fooling_orig,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
seg, seg_len, pkt1, &pkt1_len))
return verdict;
ip_id=IP4_IP_ID_NEXT(ip_id);
DLOG("sending 1st tcp segment 0-%zu len=%zu seqovl=%u : ",split_pos-1, split_pos, seqovl);
hexdump_limited_dlog(seg,seg_len,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
@ -1535,25 +1566,23 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
break;
}
#endif
if (dis->ip) ((struct ip*)fakeseg)->ip_id = ip_id;
ip_id=IP4_IP_ID_NEXT(ip_id);
DLOG("sending fake(2) 1st tcp segment 0-%zu len=%zu : ",split_pos-1, split_pos);
hexdump_limited_dlog(zeropkt,split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend_rep(dp->desync_repeats,(struct sockaddr *)&dst, desync_fwmark, ifout , fakeseg, fakeseg_len))
return verdict;
if (split_pos<dis->len_payload)
{
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, net32_add(dis->tcp->th_seq,split_pos), dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
fooling_orig,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
dis->data_payload+split_pos, dis->len_payload-split_pos, pkt1, &pkt1_len))
return verdict;
DLOG("sending 2nd tcp segment %zu-%zu len=%zu : ",split_pos,dis->len_payload-1, dis->len_payload-split_pos);
hexdump_limited_dlog(dis->data_payload+split_pos,dis->len_payload-split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
return verdict;
}
pkt1_len = sizeof(pkt1);
if (!prepare_tcp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, flags_orig, net32_add(dis->tcp->th_seq,split_pos), dis->tcp->th_ack, dis->tcp->th_win, scale_factor, timestamps,
ttl_orig,IP4_TOS(dis->ip),ip_id,IP6_FLOW(dis->ip6),
fooling_orig,dp->desync_badseq_increment,dp->desync_badseq_ack_increment,
dis->data_payload+split_pos, dis->len_payload-split_pos, pkt1, &pkt1_len))
return verdict;
DLOG("sending 2nd tcp segment %zu-%zu len=%zu : ",split_pos,dis->len_payload-1, dis->len_payload-split_pos);
hexdump_limited_dlog(dis->data_payload+split_pos,dis->len_payload-split_pos,PKTDATA_MAXDUMP); DLOG("\n");
if (!rawsend((struct sockaddr *)&dst, desync_fwmark, ifout , pkt1, pkt1_len))
return verdict;
return VERDICT_DROP;
}
@ -1566,8 +1595,9 @@ static uint8_t dpi_desync_tcp_packet_play(bool replay, size_t reasm_offset, uint
uint8_t pkt3[DPI_DESYNC_MAX_FAKE_LEN+100], *pkt_orig;
size_t pkt_orig_len;
ip_id = IP4_IP_ID_FIX(dis->ip);
uint32_t ident = dis->ip ? ip_id ? ip_id : htons(1+random()%0xFFFF) : htonl(1+random()%0xFFFFFFFF);
size_t ipfrag_pos = (dp->desync_ipfrag_pos_tcp && dp->desync_ipfrag_pos_tcp<dis->transport_len) ? dp->desync_ipfrag_pos_tcp : 24;
uint32_t ident = dis->ip ? dis->ip->ip_id ? dis->ip->ip_id : htons(1+random()%0xFFFF) : htonl(1+random()%0xFFFFFFFF);
pkt1_len = sizeof(pkt1);
pkt2_len = sizeof(pkt2);
@ -1735,6 +1765,7 @@ static uint8_t dpi_desync_udp_packet_play(bool replay, size_t reasm_offset, uint
size_t fake_size;
char host[256];
bool bHaveHost=false;
uint16_t ip_id;
if (IsQUICInitial(dis->data_payload,dis->len_payload))
{
@ -2005,7 +2036,7 @@ static uint8_t dpi_desync_udp_packet_play(bool replay, size_t reasm_offset, uint
break;
}
case DESYNC_FAKE:
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, ttl_fake, IP4_TOS(dis->ip),IP6_FLOW(dis->ip6), dp->desync_fooling_mode, NULL, 0, 0, fake, fake_size, pkt1, &pkt1_len))
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, ttl_fake, IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6), dp->desync_fooling_mode, NULL, 0, 0, fake, fake_size, pkt1, &pkt1_len))
return verdict;
DLOG("sending fake : ");
hexdump_limited_dlog(fake,fake_size,PKTDATA_MAXDUMP); DLOG("\n");
@ -2020,7 +2051,7 @@ static uint8_t dpi_desync_udp_packet_play(bool replay, size_t reasm_offset, uint
if (dis->ip6 && (dp->desync_mode2==DESYNC_NONE || !desync_valid_second_stage_udp(dp->desync_mode2)))
{
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst,
ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6),
ttl_orig,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6),
fooling_orig,NULL,0,0,
dis->data_payload, dis->len_payload, pkt1, &pkt1_len))
{
@ -2043,7 +2074,7 @@ static uint8_t dpi_desync_udp_packet_play(bool replay, size_t reasm_offset, uint
{
case DESYNC_UDPLEN:
pkt1_len = sizeof(pkt1);
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6), fooling_orig, dp->udplen_pattern, sizeof(dp->udplen_pattern), dp->udplen_increment, dis->data_payload, dis->len_payload, pkt1, &pkt1_len))
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, ttl_orig,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6), fooling_orig, dp->udplen_pattern, sizeof(dp->udplen_pattern), dp->udplen_increment, dis->data_payload, dis->len_payload, pkt1, &pkt1_len))
{
DLOG("could not construct packet with modified length. too large ?\n");
break;
@ -2068,7 +2099,7 @@ static uint8_t dpi_desync_udp_packet_play(bool replay, size_t reasm_offset, uint
memcpy(pkt2+pkt2_len,dis->data_payload+1,szcopy);
pkt2_len+=szcopy;
pkt1_len = sizeof(pkt1);
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, ttl_orig,IP4_TOS(dis->ip),IP6_FLOW(dis->ip6), fooling_orig, NULL, 0 , 0, pkt2, pkt2_len, pkt1, &pkt1_len))
if (!prepare_udp_segment((struct sockaddr *)&src, (struct sockaddr *)&dst, ttl_orig,IP4_TOS(dis->ip),IP4_IP_ID_FIX(dis->ip),IP6_FLOW(dis->ip6), fooling_orig, NULL, 0 , 0, pkt2, pkt2_len, pkt1, &pkt1_len))
{
DLOG("could not construct packet with modified length. too large ?\n");
break;
@ -2090,9 +2121,10 @@ static uint8_t dpi_desync_udp_packet_play(bool replay, size_t reasm_offset, uint
uint8_t pkt3[DPI_DESYNC_MAX_FAKE_LEN+100], *pkt_orig;
size_t pkt_orig_len;
size_t ipfrag_pos = (dp->desync_ipfrag_pos_udp && dp->desync_ipfrag_pos_udp<dis->transport_len) ? dp->desync_ipfrag_pos_udp : sizeof(struct udphdr);
// freebsd do not set ip.id
uint32_t ident = dis->ip ? dis->ip->ip_id ? dis->ip->ip_id : htons(1+random()%0xFFFF) : htonl(1+random()%0xFFFFFFFF);
ip_id = IP4_IP_ID_FIX(dis->ip);
uint32_t ident = dis->ip ? ip_id ? ip_id : htons(1+random()%0xFFFF) : htonl(1+random()%0xFFFFFFFF);
size_t ipfrag_pos = (dp->desync_ipfrag_pos_udp && dp->desync_ipfrag_pos_udp<dis->transport_len) ? dp->desync_ipfrag_pos_udp : sizeof(struct udphdr);
pkt1_len = sizeof(pkt1);
pkt2_len = sizeof(pkt2);