static void socks5_read_auth_methods(struct bufferevent *buffev, redsocks_client *client, socks5_client *socks5)
{
socks5_method_reply reply;
const char *error = NULL;
if (redsocks_read_expected(client, buffev->input, &reply, sizes_equal, sizeof(reply)) < 0)
return;
error = socks5_is_known_auth_method(&reply, socks5->do_password);
if (error) {
redsocks_log_error(client, LOG_NOTICE, "socks5_is_known_auth_method: %s", error);
redsocks_drop_client(client);
}
else if (reply.method == socks5_auth_none) {
redsocks_write_helper(
buffev, client,
socks5_mkconnect, socks5_request_sent, sizeof(socks5_reply)
);
}
else if (reply.method == socks5_auth_password) {
redsocks_write_helper(
buffev, client,
socks5_mkpassword, socks5_auth_sent, sizeof(socks5_auth_reply)
);
}
}
static void socks5_write_cb(struct bufferevent *buffev, void *_arg)
{
redsocks_client *client = _arg;
redsocks_touch_client(client);
if (client->state == socks5_new) {
redsocks_write_helper(
buffev, client,
socks5_mkmethods, socks5_method_sent, sizeof(socks5_method_reply)
);
}
}
static void socks4_write_cb(struct bufferevent *buffev, void *_arg)
{
redsocks_client *client = _arg;
redsocks_touch_client(client);
if (client->state == socks4_new) {
redsocks_write_helper(
buffev, client,
socks4_mkconnect, socks4_request_sent, sizeof(socks4_reply)
);
}
else if (client->state >= socks4_request_sent) {
bufferevent_disable(buffev, EV_WRITE);
}
}
static void socks5_read_reply(struct bufferevent *buffev, redsocks_client *client, socks5_client *socks5)
{
socks5_reply reply;
if (redsocks_read_expected(client, buffev->input, &reply, sizes_greater_equal, sizeof(reply)) < 0)
return;
if (reply.ver != socks5_ver) {
redsocks_log_error(client, LOG_NOTICE, "Socks5 server reported unexpected reply version...");
redsocks_drop_client(client);
}
else if (reply.status == socks5_status_succeeded) {
socks5_state nextstate;
size_t len;
if (reply.addrtype == socks5_addrtype_ipv4) {
len = socks5->to_skip = sizeof(socks5_addr_ipv4);
nextstate = socks5_skip_address;
}
else if (reply.addrtype == socks5_addrtype_ipv6) {
len = socks5->to_skip = sizeof(socks5_addr_ipv6);
nextstate = socks5_skip_address;
}
else if (reply.addrtype == socks5_addrtype_domain) {
socks5_addr_domain domain;
len = sizeof(domain.size);
nextstate = socks5_skip_domain;
}
else {
redsocks_log_error(client, LOG_NOTICE, "Socks5 server reported unexpected address type...");
redsocks_drop_client(client);
return;
}
redsocks_write_helper(
buffev, client,
NULL, nextstate, len
);
}
else {
redsocks_log_error(client, LOG_NOTICE, "Socks5 server status: %s (%i)",
/* 0 <= reply.status && */ reply.status < SIZEOF_ARRAY(socks5_strstatus)
? socks5_strstatus[reply.status] : "?", reply.status);
redsocks_drop_client(client);
}
}
static void socks5_read_auth_reply(struct bufferevent *buffev, redsocks_client *client, socks5_client *socks5)
{
socks5_auth_reply reply;
if (redsocks_read_expected(client, buffev->input, &reply, sizes_equal, sizeof(reply)) < 0)
return;
if (reply.ver != socks5_password_ver) {
redsocks_log_error(client, LOG_NOTICE, "Socks5 server reported unexpected auth reply version...");
redsocks_drop_client(client);
}
else if (reply.status == socks5_password_passed)
redsocks_write_helper(
buffev, client,
socks5_mkconnect, socks5_request_sent, sizeof(socks5_reply)
);
else
redsocks_drop_client(client);
}
static void socks5_read_cb(struct bufferevent *buffev, void *_arg)
{
redsocks_client *client = _arg;
socks5_client *socks5 = red_payload(client);
redsocks_touch_client(client);
if (client->state == socks5_method_sent) {
socks5_read_auth_methods(buffev, client, socks5);
}
else if (client->state == socks5_auth_sent) {
socks5_read_auth_reply(buffev, client, socks5);
}
else if (client->state == socks5_request_sent) {
socks5_read_reply(buffev, client, socks5);
}
else if (client->state == socks5_skip_domain) {
socks5_addr_ipv4 ipv4; // all socks5_addr*.port are equal
uint8_t size;
if (redsocks_read_expected(client, buffev->input, &size, sizes_greater_equal, sizeof(size)) < 0)
return;
socks5->to_skip = size + sizeof(ipv4.port);
redsocks_write_helper(
buffev, client,
NULL, socks5_skip_address, socks5->to_skip
);
}
else if (client->state == socks5_skip_address) {
uint8_t data[socks5->to_skip];
if (redsocks_read_expected(client, buffev->input, data, sizes_greater_equal, socks5->to_skip) < 0)
return;
redsocks_start_relay(client);
}
else {
redsocks_drop_client(client);
}
}
