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#include <ccan/io/io.h>
#include <ccan/short_types/short_types.h>
#include <ccan/tal/str/str.h>
#include <common/status.h>
#include <common/utils.h>
#include <common/wireaddr.h>
#include <connectd/connectd.h>
#include <connectd/tor.h>
#include <inttypes.h>
#include <netdb.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#define SOCKS_NOAUTH 0
#define SOCKS_ERROR 0xff
#define SOCKS_CONNECT 1
#define SOCKS_TYP_IPV4 1
#define SOCKS_DOMAIN 3
#define SOCKS_TYP_IPV6 4
#define SOCKS_V5 5
#define MAX_SIZE_OF_SOCKS5_REQ_OR_RESP 255
#define SIZE_OF_RESPONSE 4
#define SIZE_OF_REQUEST 3
#define SIZE_OF_IPV4_RESPONSE 6
#define SIZE_OF_IPV6_RESPONSE 18
#define SOCK_REQ_METH_LEN 3
#define SOCK_REQ_V5_LEN 5
#define SOCK_REQ_V5_HEADER_LEN 7
/* some crufts can not forward ipv6 */
#undef BIND_FIRST_TO_IPV6
struct connecting_socks {
u8 buffer[MAX_SIZE_OF_SOCKS5_REQ_OR_RESP];
size_t hlen;
in_port_t port;
char *host;
struct connecting *connect;
};
static const char* socks5strerror(const tal_t *ctx, u8 code)
{
/* Error codes defined in https://tools.ietf.org/html/rfc1928#section-6 */
switch (code) {
case 0:
return tal_strdup(ctx, "success");
case 1:
return tal_strdup(ctx, "general SOCKS server failure");
case 2:
return tal_strdup(ctx, "connection not allowed by ruleset");
case 3:
return tal_strdup(ctx, "network unreachable");
case 4:
return tal_strdup(ctx, "host unreachable");
case 5:
return tal_strdup(ctx, "connection refused");
case 6:
return tal_strdup(ctx, "TTL expired");
case 7:
return tal_strdup(ctx, "command not supported");
case 8:
return tal_strdup(ctx, "address type not supported");
}
return tal_fmt(ctx, "unknown error: %" PRIu8, code);
}
static struct io_plan *connect_finish2(struct io_conn *conn,
struct connecting_socks *connect)
{
status_io(LOG_IO_IN, NULL, "proxy",
connect->buffer + SIZE_OF_RESPONSE + SIZE_OF_IPV4_RESPONSE,
SIZE_OF_IPV6_RESPONSE - SIZE_OF_IPV4_RESPONSE);
status_debug("Now try LN connect out for host %s", connect->host);
return connection_out(conn, connect->connect);
}
static struct io_plan *connect_finish(struct io_conn *conn,
struct connecting_socks *connect)
{
status_io(LOG_IO_IN, NULL, "proxy",
connect->buffer, SIZE_OF_IPV4_RESPONSE + SIZE_OF_RESPONSE);
/* buffer[1] contains the reply status code and 0 means "success",
* see https://tools.ietf.org/html/rfc1928#section-6
*/
if ( connect->buffer[1] == '\0') {
if ( connect->buffer[3] == SOCKS_TYP_IPV6) {
/* Read rest of response */
return io_read(conn,
connect->buffer + SIZE_OF_RESPONSE +
SIZE_OF_IPV4_RESPONSE,
SIZE_OF_IPV6_RESPONSE -
SIZE_OF_IPV4_RESPONSE,
&connect_finish2, connect);
} else if ( connect->buffer[3] == SOCKS_TYP_IPV4) {
status_debug("Now try LN connect out for host %s",
connect->host);
return connection_out(conn, connect->connect);
} else {
status_debug
("Tor connect out for host %s error invalid "
"type return: %0x", connect->host,
connect->buffer[3]);
return io_close(conn);
}
} else {
status_debug("Error connecting to %s: Tor server reply: %s",
connect->host,
socks5strerror(tmpctx, connect->buffer[1]));
return io_close(conn);
}
}
/* called when TOR responds */
static struct io_plan *connect_out(struct io_conn *conn,
struct connecting_socks *connect)
{
return io_read(conn, connect->buffer,
SIZE_OF_IPV4_RESPONSE + SIZE_OF_RESPONSE,
&connect_finish, connect);
}
static struct io_plan *io_tor_connect_after_resp_to_connect(struct io_conn
*conn,
struct
connecting_socks
*connect)
{
status_io(LOG_IO_IN, NULL, "proxy", connect->buffer, 2);
if (connect->buffer[1] == SOCKS_ERROR) {
/* The Tor socks5 server did not like any of our authentication
* methods and we provided only "no auth".
*/
status_debug("Connected out for %s error: authentication required",
connect->host);
return io_close(conn);
}
if (connect->buffer[1] == '\0') {
/* make the V5 request */
connect->hlen = strlen(connect->host);
connect->buffer[0] = SOCKS_V5;
connect->buffer[1] = SOCKS_CONNECT;
connect->buffer[2] = 0;
connect->buffer[3] = SOCKS_DOMAIN;
connect->buffer[4] = connect->hlen;
memcpy(connect->buffer + SOCK_REQ_V5_LEN, connect->host, connect->hlen);
memcpy(connect->buffer + SOCK_REQ_V5_LEN + strlen(connect->host),
&(connect->port), sizeof connect->port);
status_io(LOG_IO_OUT, NULL, "proxy", connect->buffer,
SOCK_REQ_V5_HEADER_LEN + connect->hlen);
return io_write(conn, connect->buffer,
SOCK_REQ_V5_HEADER_LEN + connect->hlen,
connect_out, connect);
} else {
status_debug("Connected out for %s error: unexpected connect answer %0x from the tor socks5 proxy",
connect->host,
connect->buffer[1]);
return io_close(conn);
}
}
static struct io_plan *io_tor_connect_after_req_to_connect(struct io_conn *conn,
struct connecting_socks
*connect)
{
return io_read(conn, connect->buffer, 2,
&io_tor_connect_after_resp_to_connect, connect);
}
static struct io_plan *io_tor_connect_do_req(struct io_conn *conn,
struct connecting_socks *connect)
{
/* make the init request */
connect->buffer[0] = SOCKS_V5;
connect->buffer[1] = 1;
connect->buffer[2] = SOCKS_NOAUTH;
status_io(LOG_IO_OUT, NULL, "proxy", connect->buffer, SOCK_REQ_METH_LEN);
return io_write(conn, connect->buffer, SOCK_REQ_METH_LEN,
&io_tor_connect_after_req_to_connect, connect);
}
/* called when we want to connect to TOR SOCKS5 */
struct io_plan *io_tor_connect(struct io_conn *conn,
const struct addrinfo *tor_proxyaddr,
const char *host, u16 port,
struct connecting *connect)
{
struct connecting_socks *connect_tor = tal(connect,
struct connecting_socks);
connect_tor->port = htons(port);
connect_tor->host = tal_strdup(connect_tor, host);
connect_tor->connect = connect;
return io_connect(conn, tor_proxyaddr,
&io_tor_connect_do_req, connect_tor);
}