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TSG-13170 Decrypted Traffic Steering构造的SYN/SYN ACK支持SACK选项

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bugfix: IPv6 ACK Packet: invalid flag
This commit is contained in:
luwenpeng
2022-12-26 16:57:04 +08:00
parent 29a75b1d9c
commit dc4205c9b0
1 changed files with 32 additions and 1 deletions
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33
platform/src/acceptor_kni_v3.cpp
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@@ -284,6 +284,11 @@ struct tcp_option_window_scale{
uint8_t shift_count;
};
struct tcp_option_sack{
uint8_t kind;
uint8_t length;
};
static int fake_tcp_handshake(struct tfe_proxy *proxy, struct tcp_restore_info *restore_info)
{
char buffer[1500] = {0};
@@ -338,6 +343,32 @@ static int fake_tcp_handshake(struct tfe_proxy *proxy, struct tcp_restore_info *
tcp_option_length_s += sizeof(struct tcp_option_window_scale);
}
/*
* SACK option: Kind: 4, Length: 2
* +---------+---------+
* | Kind=4 |Length=2 |
* +---------+---------+
* 1 1
*/
if (client->sack_perm && server->sack_perm)
{
// padding
memset(tcp_option_buffer_c + tcp_option_length_c, 1, 2);
tcp_option_length_c += 2;
memset(tcp_option_buffer_s + tcp_option_length_s, 1, 2);
tcp_option_length_s += 2;
struct tcp_option_sack *option_c = (struct tcp_option_sack *)(tcp_option_buffer_c + tcp_option_length_c);
option_c->kind = 4;
option_c->length = 2;
tcp_option_length_c += sizeof(struct tcp_option_sack);
struct tcp_option_sack *option_s = (struct tcp_option_sack *)(tcp_option_buffer_s + tcp_option_length_s);
option_s->kind = 4;
option_s->length = 2;
tcp_option_length_s += sizeof(struct tcp_option_sack);
}
if (client->addr.ss_family == AF_INET6)
{
struct sockaddr_in6 *sk_client = (struct sockaddr_in6 *)&client->addr;
@@ -372,7 +403,7 @@ static int fake_tcp_handshake(struct tfe_proxy *proxy, struct tcp_restore_info *
buffer, // buffer
&raw_socket_c->mac_addr, &raw_socket_s->mac_addr, 0, ETH_P_IPV6, // Ether
&sk_client->sin6_addr, &sk_server->sin6_addr, 55, // IPv6
port_client, port_server, c_seq, s_seq, TCP_SYN_FLAG, client->window, // TCP Header
port_client, port_server, c_seq, s_seq, TCP_ACK_FLAG, client->window, // TCP Header
NULL, 0, // TCP Options
NULL, 0); // Payload
raw_socket_send(raw_socket_c, buffer, length);