jeka
/
utun2
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
Browse Source

add orig_src_ip to ICMP proxy protocol, fix deliver_reply dst_ip (was wrong tun_ip_addr)

congestion
Evgeny 5 months ago
parent
67d57c9751
commit
13d469d866
4 changed files with 37 additions and 30 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Unified View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 47
      src/icmp_proxy.c
  2. 9
      src/icmp_proxy.h
  3. 5
      src/tcp_proxy.c
  4. 6
      tests/test_icmp_proxy.c

47
src/icmp_proxy.c
Unescape View File

@ -34,7 +34,7 @@ static struct icmp_request* req_find_by_id(struct icmp_request* head, uint16_t e
// Build and send a raw ICMP echo request // Build and send a raw ICMP echo request
static int exit_send_echo(struct UTUN_INSTANCE* inst, uint64_t client_node_id, static int exit_send_echo(struct UTUN_INSTANCE* inst, uint64_t client_node_id,
uint32_t dst_ip, uint16_t echo_id, uint16_t echo_seq, uint32_t dst_ip, uint32_t orig_src_ip, uint16_t echo_id, uint16_t echo_seq,
const uint8_t* payload, size_t payload_len) { const uint8_t* payload, size_t payload_len) {
if (!g_icmp_ctx || g_icmp_ctx->raw_sock == SOCKET_INVALID) return -1; if (!g_icmp_ctx || g_icmp_ctx->raw_sock == SOCKET_INVALID) return -1;
size_t icmp_len = ICMP_MINLEN + payload_len; size_t icmp_len = ICMP_MINLEN + payload_len;
@ -64,7 +64,7 @@ static int exit_send_echo(struct UTUN_INSTANCE* inst, uint64_t client_node_id,
struct icmp_request* r = u_calloc(1, sizeof(struct icmp_request)); struct icmp_request* r = u_calloc(1, sizeof(struct icmp_request));
if (!r) return 0; if (!r) return 0;
r->client_node_id = client_node_id; r->dst_ip = dst_ip; r->client_node_id = client_node_id; r->dst_ip = dst_ip; r->orig_src_ip = orig_src_ip;
r->echo_id = echo_id; r->echo_seq = echo_seq; r->echo_id = echo_id; r->echo_seq = echo_seq;
r->payload_len = payload_len > sizeof(r->payload) ? sizeof(r->payload) : payload_len; r->payload_len = payload_len > sizeof(r->payload) ? sizeof(r->payload) : payload_len;
if (payload_len > 0) memcpy(r->payload, payload, r->payload_len); if (payload_len > 0) memcpy(r->payload, payload, r->payload_len);
@ -108,8 +108,9 @@ static void raw_read_cb(socket_t sock, void* arg) {
e->dgram[1] = ICMP_PROXY_SUBCMD_REPLY; e->dgram[1] = ICMP_PROXY_SUBCMD_REPLY;
memcpy(e->dgram + 2, &r->client_node_id, 8); memcpy(e->dgram + 2, &r->client_node_id, 8);
memcpy(e->dgram + 10, &r->dst_ip, 4); memcpy(e->dgram + 10, &r->dst_ip, 4);
memcpy(e->dgram + 14, &icmp_hdr->icmp_id, 2); memcpy(e->dgram + 14, &r->orig_src_ip, 4);
memcpy(e->dgram + 16, &icmp_hdr->icmp_seq, 2); memcpy(e->dgram + 18, &icmp_hdr->icmp_id, 2);
memcpy(e->dgram + 20, &icmp_hdr->icmp_seq, 2);
if (payload_len > 0) memcpy(e->dgram + ICMP_PROXY_HDR_SIZE, payload, payload_len); if (payload_len > 0) memcpy(e->dgram + ICMP_PROXY_HDR_SIZE, payload, payload_len);
e->len = ICMP_PROXY_HDR_SIZE + payload_len; e->len = ICMP_PROXY_HDR_SIZE + payload_len;
int ret = etcp_route_send(g_icmp_ctx->inst, r->client_node_id, e); int ret = etcp_route_send(g_icmp_ctx->inst, r->client_node_id, e);
@ -125,14 +126,15 @@ static void exit_handle_request(struct ETCP_CONN* conn, struct ll_entry* entry)
if (!inst || !g_icmp_ctx || entry->len < ICMP_PROXY_HDR_SIZE + 1) goto drop; if (!inst || !g_icmp_ctx || entry->len < ICMP_PROXY_HDR_SIZE + 1) goto drop;
uint64_t client_node_id; memcpy(&client_node_id, entry->dgram + 2, 8); uint64_t client_node_id; memcpy(&client_node_id, entry->dgram + 2, 8);
uint32_t dst_ip; memcpy(&dst_ip, entry->dgram + 10, 4); uint32_t dst_ip; memcpy(&dst_ip, entry->dgram + 10, 4);
uint16_t echo_id; memcpy(&echo_id, entry->dgram + 14, 2); uint32_t orig_src_ip; memcpy(&orig_src_ip, entry->dgram + 14, 4);
uint16_t echo_seq; memcpy(&echo_seq, entry->dgram + 16, 2); uint16_t echo_id; memcpy(&echo_id, entry->dgram + 18, 2);
uint16_t echo_seq; memcpy(&echo_seq, entry->dgram + 20, 2);
uint8_t* payload = entry->dgram + ICMP_PROXY_HDR_SIZE; uint8_t* payload = entry->dgram + ICMP_PROXY_HDR_SIZE;
size_t payload_len = entry->len - ICMP_PROXY_HDR_SIZE; size_t payload_len = entry->len - ICMP_PROXY_HDR_SIZE;
if (g_icmp_ctx->raw_sock != SOCKET_INVALID) { if (g_icmp_ctx->raw_sock != SOCKET_INVALID) {
exit_send_echo(inst, client_node_id, dst_ip, echo_id, echo_seq, payload, payload_len); exit_send_echo(inst, client_node_id, dst_ip, orig_src_ip, echo_id, echo_seq, payload, payload_len);
} else if (g_icmp_ctx->test_loopback) { } else if (g_icmp_ctx->test_loopback) {
DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "icmp_proxy: test loopback reply to 0x%08x", dst_ip); DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "icmp_proxy: test loopback reply to 0x%08x", dst_ip);
struct ll_entry* e = queue_entry_new(0); struct ll_entry* e = queue_entry_new(0);
@ -143,8 +145,9 @@ static void exit_handle_request(struct ETCP_CONN* conn, struct ll_entry* entry)
e->dgram[1] = ICMP_PROXY_SUBCMD_REPLY; e->dgram[1] = ICMP_PROXY_SUBCMD_REPLY;
memcpy(e->dgram + 2, &client_node_id, 8); memcpy(e->dgram + 2, &client_node_id, 8);
memcpy(e->dgram + 10, &dst_ip, 4); memcpy(e->dgram + 10, &dst_ip, 4);
memcpy(e->dgram + 14, &echo_id, 2); memcpy(e->dgram + 14, &orig_src_ip, 4);
memcpy(e->dgram + 16, &echo_seq, 2); memcpy(e->dgram + 18, &echo_id, 2);
memcpy(e->dgram + 20, &echo_seq, 2);
if (payload_len > 0) memcpy(e->dgram + ICMP_PROXY_HDR_SIZE, payload, payload_len); if (payload_len > 0) memcpy(e->dgram + ICMP_PROXY_HDR_SIZE, payload, payload_len);
e->len = ICMP_PROXY_HDR_SIZE + payload_len; e->len = ICMP_PROXY_HDR_SIZE + payload_len;
etcp_route_send(inst, client_node_id, e); etcp_route_send(inst, client_node_id, e);
@ -164,14 +167,16 @@ drop:
static void client_handle_reply(struct ETCP_CONN* conn, struct ll_entry* entry) { static void client_handle_reply(struct ETCP_CONN* conn, struct ll_entry* entry) {
if (entry->len < ICMP_PROXY_HDR_SIZE + 1) { queue_entry_free(entry); queue_dgram_free(entry); return; } if (entry->len < ICMP_PROXY_HDR_SIZE + 1) { queue_entry_free(entry); queue_dgram_free(entry); return; }
uint32_t src_ip; uint32_t src_ip;
uint32_t orig_src_ip;
uint16_t echo_id, echo_seq; uint16_t echo_id, echo_seq;
memcpy(&src_ip, entry->dgram + 10, 4); memcpy(&src_ip, entry->dgram + 10, 4);
memcpy(&echo_id, entry->dgram + 14, 2); memcpy(&orig_src_ip, entry->dgram + 14, 4);
memcpy(&echo_seq, entry->dgram + 16, 2); memcpy(&echo_id, entry->dgram + 18, 2);
DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "icmp_proxy: client got reply id=0x%04x seq=%u from=0x%08x", memcpy(&echo_seq, entry->dgram + 20, 2);
echo_id, echo_seq, src_ip); DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "icmp_proxy: client got reply id=0x%04x seq=%u from=0x%08x dst=0x%08x",
echo_id, echo_seq, src_ip, orig_src_ip);
struct UTUN_INSTANCE* inst = conn ? conn->instance : (g_icmp_ctx ? g_icmp_ctx->inst : NULL); struct UTUN_INSTANCE* inst = conn ? conn->instance : (g_icmp_ctx ? g_icmp_ctx->inst : NULL);
icmp_proxy_deliver_reply(inst, src_ip, echo_id, echo_seq, icmp_proxy_deliver_reply(inst, orig_src_ip, src_ip, echo_id, echo_seq,
entry->dgram + ICMP_PROXY_HDR_SIZE, entry->len - ICMP_PROXY_HDR_SIZE); entry->dgram + ICMP_PROXY_HDR_SIZE, entry->len - ICMP_PROXY_HDR_SIZE);
queue_entry_free(entry); queue_dgram_free(entry); queue_entry_free(entry); queue_dgram_free(entry);
} }
@ -194,7 +199,7 @@ void icmp_proxy_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry) {
// Client side: send ICMP echo request to exit node // Client side: send ICMP echo request to exit node
// ==================================================================== // ====================================================================
int icmp_proxy_send_to_exit(struct UTUN_INSTANCE* inst, uint64_t exit_node_id, int icmp_proxy_send_to_exit(struct UTUN_INSTANCE* inst, uint64_t exit_node_id,
uint32_t dst_ip, uint16_t echo_id, uint16_t echo_seq, uint32_t dst_ip, uint32_t orig_src_ip, uint16_t echo_id, uint16_t echo_seq,
const uint8_t* payload, size_t payload_len) { const uint8_t* payload, size_t payload_len) {
if (!inst) return -1; if (!inst) return -1;
struct ll_entry* e = queue_entry_new(0); struct ll_entry* e = queue_entry_new(0);
@ -205,8 +210,9 @@ int icmp_proxy_send_to_exit(struct UTUN_INSTANCE* inst, uint64_t exit_node_id,
e->dgram[1] = ICMP_PROXY_SUBCMD_REQUEST; e->dgram[1] = ICMP_PROXY_SUBCMD_REQUEST;
memcpy(e->dgram + 2, &inst->node_id, 8); memcpy(e->dgram + 2, &inst->node_id, 8);
memcpy(e->dgram + 10, &dst_ip, 4); memcpy(e->dgram + 10, &dst_ip, 4);
memcpy(e->dgram + 14, &echo_id, 2); memcpy(e->dgram + 14, &orig_src_ip, 4);
memcpy(e->dgram + 16, &echo_seq, 2); memcpy(e->dgram + 18, &echo_id, 2);
memcpy(e->dgram + 20, &echo_seq, 2);
if (payload_len > 0) memcpy(e->dgram + ICMP_PROXY_HDR_SIZE, payload, payload_len); if (payload_len > 0) memcpy(e->dgram + ICMP_PROXY_HDR_SIZE, payload, payload_len);
e->len = ICMP_PROXY_HDR_SIZE + payload_len; e->len = ICMP_PROXY_HDR_SIZE + payload_len;
return etcp_route_send(inst, exit_node_id, e); return etcp_route_send(inst, exit_node_id, e);
@ -216,7 +222,7 @@ int icmp_proxy_send_to_exit(struct UTUN_INSTANCE* inst, uint64_t exit_node_id,
// Client side: deliver ICMP echo reply to TUN // Client side: deliver ICMP echo reply to TUN
// ==================================================================== // ====================================================================
int icmp_proxy_deliver_reply(struct UTUN_INSTANCE* inst, int icmp_proxy_deliver_reply(struct UTUN_INSTANCE* inst,
uint32_t src_ip, uint16_t echo_id, uint16_t echo_seq, uint32_t dst_ip, uint32_t src_ip, uint16_t echo_id, uint16_t echo_seq,
const uint8_t* payload, size_t payload_len) { const uint8_t* payload, size_t payload_len) {
if (!inst || !inst->tcp_proxy || !inst->tcp_proxy->tun) { if (!inst || !inst->tcp_proxy || !inst->tcp_proxy->tun) {
DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "icmp_proxy: deliver_reply failed — no %s", DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "icmp_proxy: deliver_reply failed — no %s",
@ -224,7 +230,6 @@ int icmp_proxy_deliver_reply(struct UTUN_INSTANCE* inst,
return -1; return -1;
} }
struct tun_if* tun = inst->tcp_proxy->tun; struct tun_if* tun = inst->tcp_proxy->tun;
uint32_t dst_ip = inst->tcp_proxy->tun_ip_addr;
size_t icmp_len = ICMP_MINLEN + payload_len; size_t icmp_len = ICMP_MINLEN + payload_len;
size_t pkt_len = 20 + icmp_len; size_t pkt_len = 20 + icmp_len;

9
src/icmp_proxy.h
Unescape View File

@ -15,14 +15,15 @@ struct ETCP_CONN;
#define ICMP_PROXY_SUBCMD_REPLY 0x02 // exit→client: echo reply #define ICMP_PROXY_SUBCMD_REPLY 0x02 // exit→client: echo reply
// Message header (excluding svc_id byte) // Message header (excluding svc_id byte)
// svc_id(1) + subcmd(1) + sender_node_id(8) + dst_ip(4) + icmp_id(2) + icmp_seq(2) + payload // svc_id(1) + subcmd(1) + sender_node_id(8) + dst_ip(4) + orig_src_ip(4) + icmp_id(2) + icmp_seq(2) + payload
#define ICMP_PROXY_HDR_SIZE 18 #define ICMP_PROXY_HDR_SIZE 22
// In-flight ICMP echo request (exit node side) // In-flight ICMP echo request (exit node side)
struct icmp_request { struct icmp_request {
struct icmp_request* next; struct icmp_request* next;
uint64_t client_node_id; uint64_t client_node_id;
uint32_t dst_ip; uint32_t dst_ip;
uint32_t orig_src_ip; // IP исходного отправителя (чтобы вернуть reply правильному адресату)
uint16_t echo_id; uint16_t echo_id;
uint16_t echo_seq; uint16_t echo_seq;
uint8_t payload[1500]; uint8_t payload[1500];
@ -51,11 +52,11 @@ void icmp_proxy_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry);
// Client side: принять IP/ICMP echo request с TUN, отправить через etcp // Client side: принять IP/ICMP echo request с TUN, отправить через etcp
int icmp_proxy_send_to_exit(struct UTUN_INSTANCE* inst, uint64_t exit_node_id, int icmp_proxy_send_to_exit(struct UTUN_INSTANCE* inst, uint64_t exit_node_id,
uint32_t dst_ip, uint16_t echo_id, uint16_t echo_seq, uint32_t dst_ip, uint32_t orig_src_ip, uint16_t echo_id, uint16_t echo_seq,
const uint8_t* payload, size_t payload_len); const uint8_t* payload, size_t payload_len);
int icmp_proxy_deliver_reply(struct UTUN_INSTANCE* inst, int icmp_proxy_deliver_reply(struct UTUN_INSTANCE* inst,
uint32_t src_ip, uint16_t echo_id, uint16_t echo_seq, uint32_t dst_ip, uint32_t src_ip, uint16_t echo_id, uint16_t echo_seq,
const uint8_t* payload, size_t payload_len); const uint8_t* payload, size_t payload_len);
void icmp_proxy_set_test_loopback(struct UTUN_INSTANCE* inst, int enabled); void icmp_proxy_set_test_loopback(struct UTUN_INSTANCE* inst, int enabled);

5
src/tcp_proxy.c
Unescape View File

@ -162,10 +162,11 @@ static int tcp_proxy_handle_non_tcp(struct tcp_proxy* p, uint8_t* buf, size_t le
if (len < 28) return 0; if (len < 28) return 0;
uint8_t icmp_type = buf[20]; uint8_t icmp_type = buf[20];
if (icmp_type != 8) return 0; if (icmp_type != 8) return 0;
uint32_t dst_ip; memcpy(&dst_ip, buf + 16, 4); uint32_t src_ip, dst_ip;
memcpy(&src_ip, buf + 12, 4); memcpy(&dst_ip, buf + 16, 4);
uint16_t icmp_id, icmp_seq; uint16_t icmp_id, icmp_seq;
memcpy(&icmp_id, buf + 24, 2); memcpy(&icmp_seq, buf + 26, 2); memcpy(&icmp_id, buf + 24, 2); memcpy(&icmp_seq, buf + 26, 2);
icmp_proxy_send_to_exit(p->inst, p->via_node_id, dst_ip, icmp_id, icmp_seq, buf + 28, len - 28); icmp_proxy_send_to_exit(p->inst, p->via_node_id, dst_ip, src_ip, icmp_id, icmp_seq, buf + 28, len - 28);
return 1; return 1;
} }
return 0; return 0;

6
tests/test_icmp_proxy.c
Unescape View File

@ -89,8 +89,8 @@ static void cli_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry) {
} }
if (entry->dgram[1] == ICMP_PROXY_SUBCMD_REPLY) { if (entry->dgram[1] == ICMP_PROXY_SUBCMD_REPLY) {
uint16_t rid, rseq; uint16_t rid, rseq;
memcpy(&rid, entry->dgram + 14, 2); memcpy(&rid, entry->dgram + 18, 2);
memcpy(&rseq, entry->dgram + 16, 2); memcpy(&rseq, entry->dgram + 20, 2);
if (rid == test_echo_id && rseq == test_echo_seq) { if (rid == test_echo_id && rseq == test_echo_seq) {
size_t payload_len = entry->len - ICMP_PROXY_HDR_SIZE; size_t payload_len = entry->len - ICMP_PROXY_HDR_SIZE;
uint8_t* payload = entry->dgram + ICMP_PROXY_HDR_SIZE; uint8_t* payload = entry->dgram + ICMP_PROXY_HDR_SIZE;
@ -126,7 +126,7 @@ static void monitor(void* arg) {
etcp_router_bind(cli, ETCP_ID_ICMP_PROXY, cli_recv_cb); etcp_router_bind(cli, ETCP_ID_ICMP_PROXY, cli_recv_cb);
for (int i = 0; i < ICMP_PAYLOAD_SIZE; i++) send_buf[i] = (uint8_t)(rand() & 0xFF); for (int i = 0; i < ICMP_PAYLOAD_SIZE; i++) send_buf[i] = (uint8_t)(rand() & 0xFF);
icmp_proxy_send_to_exit(cli, exit_node_id, icmp_proxy_send_to_exit(cli, exit_node_id,
inet_addr("127.0.0.1"), test_echo_id, test_echo_seq, send_buf, ICMP_PAYLOAD_SIZE); inet_addr("127.0.0.1"), inet_addr("127.0.0.100"), test_echo_id, test_echo_seq, send_buf, ICMP_PAYLOAD_SIZE);
} }
} }
if (!g_done) g_to_id = uasync_set_timeout(ua, 100, NULL, monitor, "mon"); if (!g_done) g_to_id = uasync_set_timeout(ua, 100, NULL, monitor, "mon");

Write Preview
Loading…
Cancel
Save