StunUsageIceReturn
stun_usage_ice_conncheck_create_reply (StunAgent *agent, StunMessage *req,
StunMessage *msg, uint8_t *buf, size_t *plen,
const struct sockaddr *src, socklen_t srclen,
bool *control, uint64_t tie,
StunUsageIceCompatibility compatibility)
{
const char *username = NULL;
uint16_t username_len;
size_t len = *plen;
uint64_t q;
StunMessageReturn val = STUN_MESSAGE_RETURN_SUCCESS;
StunUsageIceReturn ret = STUN_USAGE_ICE_RETURN_SUCCESS;
#define err( code ) \
stun_bind_error (agent, msg, buf, &len, req, code); \
*plen = len
*plen = 0;
stun_debug ("STUN Reply (buffer size = %u)...\n", (unsigned)len);
if (stun_message_get_class (req) != STUN_REQUEST)
{
stun_debug (" Unhandled non-request (class %u) message.\n",
stun_message_get_class (req));
return STUN_USAGE_ICE_RETURN_INVALID_REQUEST;
}
if (stun_message_get_method (req) != STUN_BINDING)
{
stun_debug (" Bad request (method %u) message.\n",
stun_message_get_method (req));
err (STUN_ERROR_BAD_REQUEST);
return STUN_USAGE_ICE_RETURN_INVALID_METHOD;
}
/* Role conflict handling */
assert (control != NULL);
if (stun_message_find64 (req, *control ? STUN_ATTRIBUTE_ICE_CONTROLLING
: STUN_ATTRIBUTE_ICE_CONTROLLED, &q) == STUN_MESSAGE_RETURN_SUCCESS)
{
stun_debug ("STUN Role Conflict detected:\n");
if (tie < q)
{
stun_debug (" switching role from \"controll%s\" to \"controll%s\"\n",
*control ? "ing" : "ed", *control ? "ed" : "ing");
*control = !*control;
ret = STUN_USAGE_ICE_RETURN_ROLE_CONFLICT;
}
else
{
stun_debug (" staying \"controll%s\" (sending error)\n",
*control ? "ing" : "ed");
err (STUN_ERROR_ROLE_CONFLICT);
return STUN_USAGE_ICE_RETURN_SUCCESS;
}
} else {
stun_debug ("STUN Role not specified by peer!\n");
}
if (stun_agent_init_response (agent, msg, buf, len, req) == FALSE) {
stun_debug ("Unable to create response\n");
goto failure;
}
if (compatibility == STUN_USAGE_ICE_COMPATIBILITY_MSN) {
StunTransactionId transid;
uint32_t magic_cookie;
stun_message_id (msg, transid);
magic_cookie = *((uint32_t *) transid);
val = stun_message_append_xor_addr_full (msg, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
src, srclen, htonl (magic_cookie));
} else if (stun_message_has_cookie (msg)) {
val = stun_message_append_xor_addr (msg, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
src, srclen);
} else {
val = stun_message_append_addr (msg, STUN_ATTRIBUTE_MAPPED_ADDRESS,
src, srclen);
}
if (val != STUN_MESSAGE_RETURN_SUCCESS) {
stun_debug (" Mapped address problem: %d\n", val);
goto failure;
}
username = (const char *)stun_message_find (req,
STUN_ATTRIBUTE_USERNAME, &username_len);
if (username) {
val = stun_message_append_bytes (msg, STUN_ATTRIBUTE_USERNAME,
username, username_len);
}
if (val != STUN_MESSAGE_RETURN_SUCCESS) {
stun_debug ("Error appending username: %d\n", val);
goto failure;
}
/* the stun agent will automatically use the password of the request */
len = stun_agent_finish_message (agent, msg, NULL, 0);
if (len == 0)
goto failure;
*plen = len;
stun_debug (" All done (response size: %u)\n", (unsigned)len);
return ret;
failure:
assert (*plen == 0);
stun_debug (" Fatal error formatting Response: %d\n", val);
switch (val)
{
case STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE:
return STUN_USAGE_ICE_RETURN_MEMORY_ERROR;
case STUN_MESSAGE_RETURN_INVALID:
case STUN_MESSAGE_RETURN_UNSUPPORTED_ADDRESS:
return STUN_USAGE_ICE_RETURN_INVALID_ADDRESS;
default:
return STUN_USAGE_ICE_RETURN_ERROR;
}
}
/** Various responses test */
static void responses (void)
{
struct sockaddr_storage addr;
socklen_t addrlen = sizeof (addr);
ssize_t val;
size_t len;
int servfd, fd;
uint8_t buf[STUN_MAX_MESSAGE_SIZE];
uint8_t req[STUN_MAX_MESSAGE_SIZE];
size_t req_len;
StunAgent agent;
StunMessage msg;
StunMessage req_msg;
uint16_t known_attributes[] = {
STUN_ATTRIBUTE_MAPPED_ADDRESS,
STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
STUN_ATTRIBUTE_PRIORITY,
STUN_ATTRIBUTE_USERNAME,
STUN_ATTRIBUTE_MESSAGE_INTEGRITY,
STUN_ATTRIBUTE_ERROR_CODE, 0};
stun_agent_init (&agent, known_attributes,
STUN_COMPATIBILITY_RFC5389, 0);
/* Allocate a local UDP port for server */
servfd = listen_dgram ();
assert (servfd != -1);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
/* Allocate a client socket and connect to server */
fd = socket (addr.ss_family, SOCK_DGRAM, 0);
assert (fd != -1);
/* Send error response */
req_len = stun_usage_bind_create (&agent, &req_msg, req, sizeof(req));
assert (req_len > 0);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
val = sendto (fd, req, req_len, MSG_DONTWAIT | MSG_NOSIGNAL,
(struct sockaddr *)&addr, addrlen);
assert (val >= 0);
val = recvfrom (servfd, buf, 1000, MSG_DONTWAIT, NULL, 0);
assert (val >= 0);
assert (stun_agent_validate (&agent, &msg, buf, val, NULL, NULL)
== STUN_VALIDATION_SUCCESS);
stun_agent_init_error (&agent, &msg, buf, sizeof (buf),
&msg, STUN_ERROR_SERVER_ERROR);
len = stun_agent_finish_message (&agent, &msg, NULL, 0);
assert (len > 0);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
val = stun_usage_bind_process (&msg, (struct sockaddr *) &addr, &addrlen,
(struct sockaddr *) &addr, &addrlen);
assert (val == STUN_USAGE_BIND_RETURN_ERROR);
/* Send response with a no mapped address at all */
req_len = stun_usage_bind_create (&agent, &req_msg, req, sizeof(req));
assert (req_len > 0);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
val = sendto (fd, req, req_len, MSG_DONTWAIT | MSG_NOSIGNAL,
(struct sockaddr *)&addr, addrlen);
assert (val >= 0);
val = recvfrom (servfd, buf, 1000, MSG_DONTWAIT, NULL, 0);
assert (val >= 0);
assert (stun_agent_validate (&agent, &msg, buf, val, NULL, NULL)
== STUN_VALIDATION_SUCCESS);
stun_agent_init_response (&agent, &msg, buf, sizeof (buf), &msg);
len = stun_agent_finish_message (&agent, &msg, NULL, 0);
assert (len > 0);
assert (stun_agent_validate (&agent, &msg, buf, len, NULL, NULL)
== STUN_VALIDATION_SUCCESS);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
val = stun_usage_bind_process (&msg, (struct sockaddr *) &addr, &addrlen,
(struct sockaddr *) &addr, &addrlen);
assert (val == STUN_USAGE_BIND_RETURN_ERROR);
/* Send old-style response */
req_len = stun_usage_bind_create (&agent, &req_msg, req, sizeof(req));
assert (req_len > 0);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
val = sendto (fd, req, req_len, MSG_DONTWAIT | MSG_NOSIGNAL,
(struct sockaddr *)&addr, addrlen);
assert (val >= 0);
val = recvfrom (servfd, buf, 1000, MSG_DONTWAIT, NULL, 0);
assert (val >= 0);
assert (stun_agent_validate (&agent, &msg, buf, val, NULL, NULL)
== STUN_VALIDATION_SUCCESS);
stun_agent_init_response (&agent, &msg, buf, sizeof (buf), &msg);
assert (stun_message_append_addr (&msg, STUN_ATTRIBUTE_MAPPED_ADDRESS,
(struct sockaddr *) &addr, addrlen) == STUN_MESSAGE_RETURN_SUCCESS);
len = stun_agent_finish_message (&agent, &msg, NULL, 0);
assert (len > 0);
assert (stun_agent_validate (&agent, &msg, buf, len, NULL, NULL)
== STUN_VALIDATION_SUCCESS);
val = getsockname (servfd, (struct sockaddr *)&addr, &addrlen);
assert (val == 0);
val = stun_usage_bind_process (&msg, (struct sockaddr *) &addr, &addrlen,
(struct sockaddr *) &addr, &addrlen);
assert (val == STUN_USAGE_BIND_RETURN_SUCCESS);
/* End */
close (servfd);
val = close (fd);
assert (val == 0);
}
static int dgram_process (int sock, StunAgent *oldagent, StunAgent *newagent)
{
union {
struct sockaddr_storage storage;
struct sockaddr addr;
} addr;
socklen_t addr_len;
uint8_t buf[STUN_MAX_MESSAGE_SIZE];
size_t buf_len = 0;
size_t len = 0;
StunMessage request;
StunMessage response;
StunValidationStatus validation;
StunAgent *agent = NULL;
gint ret;
addr_len = sizeof (struct sockaddr_in);
recv_packet:
len = recvfrom (sock, buf, sizeof(buf), 0,
&addr.addr, &addr_len);
if (drop_stun_packets) {
g_debug ("Dropping STUN packet as requested");
return -1;
}
if (len == (size_t)-1) {
return -1;
}
validation = stun_agent_validate (newagent, &request, buf, len, NULL, 0);
if (validation == STUN_VALIDATION_SUCCESS) {
agent = newagent;
} else {
validation = stun_agent_validate (oldagent, &request, buf, len, NULL, 0);
agent = oldagent;
}
/* Unknown attributes */
if (validation == STUN_VALIDATION_UNKNOWN_REQUEST_ATTRIBUTE) {
buf_len = stun_agent_build_unknown_attributes_error (agent, &response, buf,
sizeof (buf), &request);
goto send_buf;
}
/* Mal-formatted packets */
if (validation != STUN_VALIDATION_SUCCESS ||
stun_message_get_class (&request) != STUN_REQUEST) {
goto recv_packet;
}
switch (stun_message_get_method (&request)) {
case STUN_BINDING:
stun_agent_init_response (agent, &response, buf, sizeof (buf), &request);
if (stun_message_has_cookie (&request))
stun_message_append_xor_addr (&response,
STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
&addr.storage, addr_len);
else
stun_message_append_addr (&response, STUN_ATTRIBUTE_MAPPED_ADDRESS,
&addr.addr, addr_len);
break;
case STUN_SHARED_SECRET:
case STUN_ALLOCATE:
case STUN_SET_ACTIVE_DST:
case STUN_CONNECT:
case STUN_OLD_SET_ACTIVE_DST:
case STUN_IND_DATA:
case STUN_IND_CONNECT_STATUS:
case STUN_CHANNELBIND:
default:
if (!stun_agent_init_error (agent, &response, buf, sizeof (buf),
&request, STUN_ERROR_BAD_REQUEST)) {
g_debug ("STUN error message not initialized properly");
g_assert_not_reached();
}
}
buf_len = stun_agent_finish_message (agent, &response, NULL, 0);
send_buf:
g_cancellable_cancel (global_cancellable);
g_debug ("Ready to send a STUN response");
g_assert (g_mutex_trylock (stun_mutex_ptr));
got_stun_packet = TRUE;
while (send_stun) {
g_debug ("Waiting for signal. State is %d", global_lagent_state);
g_cond_wait (stun_signal_ptr, stun_mutex_ptr);
}
g_mutex_unlock (stun_mutex_ptr);
len = sendto (sock, buf, buf_len, 0,
&addr.addr, addr_len);
g_debug ("STUN response sent");
drop_stun_packets = TRUE;
ret = (len < buf_len) ? -1 : 0;
return ret;
}
static int dgram_process (int sock, StunAgent *oldagent, StunAgent *newagent)
{
union {
struct sockaddr_storage storage;
struct sockaddr addr;
} addr;
socklen_t addr_len;
uint8_t buf[STUN_MAX_MESSAGE_SIZE];
size_t buf_len = 0;
size_t len = 0;
StunMessage request;
StunMessage response;
StunValidationStatus validation;
StunAgent *agent = NULL;
addr_len = sizeof (struct sockaddr_in);
len = recvfrom (sock, buf, sizeof(buf), 0, &addr.addr, &addr_len);
if (len == (size_t)-1)
return -1;
validation = stun_agent_validate (newagent, &request, buf, len, NULL, 0);
if (validation == STUN_VALIDATION_SUCCESS) {
agent = newagent;
}
else {
validation = stun_agent_validate (oldagent, &request, buf, len, NULL, 0);
agent = oldagent;
}
/* Unknown attributes */
if (validation == STUN_VALIDATION_UNKNOWN_REQUEST_ATTRIBUTE)
{
buf_len = stun_agent_build_unknown_attributes_error (agent, &response, buf,
sizeof (buf), &request);
goto send_buf;
}
/* Mal-formatted packets */
if (validation != STUN_VALIDATION_SUCCESS ||
stun_message_get_class (&request) != STUN_REQUEST) {
return -1;
}
switch (stun_message_get_method (&request))
{
case STUN_BINDING:
stun_agent_init_response (agent, &response, buf, sizeof (buf), &request);
if (stun_message_has_cookie (&request))
stun_message_append_xor_addr (&response,
STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS, &addr.addr, addr_len);
else
stun_message_append_addr (&response, STUN_ATTRIBUTE_MAPPED_ADDRESS,
&addr.addr, addr_len);
break;
case STUN_SHARED_SECRET:
case STUN_ALLOCATE:
case STUN_SEND:
case STUN_CONNECT:
case STUN_IND_SEND:
case STUN_IND_DATA:
case STUN_CREATEPERMISSION:
case STUN_CHANNELBIND:
default:
if (!stun_agent_init_error (agent, &response, buf, sizeof (buf),
&request, STUN_ERROR_BAD_REQUEST))
return -1;
}
buf_len = stun_agent_finish_message (agent, &response, NULL, 0);
send_buf:
len = sendto (sock, buf, buf_len, 0, &addr.addr, addr_len);
return (len < buf_len) ? -1 : 0;
}
static int dgram_process (int sock, StunAgent *oldagent, StunAgent *newagent)
{
struct sockaddr_storage addr;
uint8_t buf[STUN_MAX_MESSAGE_SIZE];
char ctlbuf[CMSG_SPACE (sizeof (struct in6_pktinfo))];
struct iovec iov = { buf, sizeof (buf) };
StunMessage request;
StunMessage response;
StunValidationStatus validation;
StunAgent *agent = NULL;
struct msghdr mh =
{
.msg_name = (struct sockaddr *)&addr,
.msg_namelen = sizeof (addr),
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = ctlbuf,
.msg_controllen = sizeof (ctlbuf)
};
size_t len = recv_safe (sock, &mh);
if (len == (size_t)-1)
return -1;
validation = stun_agent_validate (newagent, &request, buf, len, NULL, 0);
if (validation == STUN_VALIDATION_SUCCESS) {
agent = newagent;
}
else {
validation = stun_agent_validate (oldagent, &request, buf, len, NULL, 0);
agent = oldagent;
}
/* Unknown attributes */
if (validation == STUN_VALIDATION_UNKNOWN_REQUEST_ATTRIBUTE)
{
stun_agent_build_unknown_attributes_error (agent, &response, buf,
sizeof (buf), &request);
goto send_buf;
}
/* Mal-formatted packets */
if (validation != STUN_VALIDATION_SUCCESS ||
stun_message_get_class (&request) != STUN_REQUEST) {
return -1;
}
switch (stun_message_get_method (&request))
{
case STUN_BINDING:
stun_agent_init_response (agent, &response, buf, sizeof (buf), &request);
if (stun_message_has_cookie (&request))
stun_message_append_xor_addr (&response,
STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
mh.msg_name, mh.msg_namelen);
else
stun_message_append_addr (&response, STUN_ATTRIBUTE_MAPPED_ADDRESS,
mh.msg_name, mh.msg_namelen);
break;
default:
stun_agent_init_error (agent, &response, buf, sizeof (buf),
&request, STUN_ERROR_BAD_REQUEST);
}
iov.iov_len = stun_agent_finish_message (agent, &response, NULL, 0);
send_buf:
len = send_safe (sock, &mh);
return (len < iov.iov_len) ? -1 : 0;
}
static int run (int family, int protocol, unsigned port)
{
StunAgent oldagent;
StunAgent newagent;
int sock = listen_socket (family, SOCK_DGRAM, protocol, port);
if (sock == -1)
return -1;
stun_agent_init (&oldagent, known_attributes,
STUN_COMPATIBILITY_RFC3489, 0);
stun_agent_init (&newagent, known_attributes,
STUN_COMPATIBILITY_RFC5389, STUN_AGENT_USAGE_USE_FINGERPRINT);
for (;;)
dgram_process (sock, &oldagent, &newagent);
}
int main (void)
{
uint8_t buf[100];
size_t len;
struct sockaddr addr;
StunAgent agent;
StunMessage msg;
uint16_t known_attributes[] = {STUN_ATTRIBUTE_USERNAME,
STUN_ATTRIBUTE_MESSAGE_INTEGRITY,
STUN_ATTRIBUTE_ERROR_CODE,
0};
stun_agent_init (&agent, known_attributes,
STUN_COMPATIBILITY_RFC5389, STUN_AGENT_USAGE_USE_FINGERPRINT);
/* Request formatting test */
stun_agent_init_request (&agent, &msg, buf, sizeof(buf), STUN_BINDING);
finish_check (&agent, &msg);
if (memcmp (buf, "\x00\x01", 2))
fatal ("Request formatting test failed");
/* Response formatting test */
stun_agent_init_response (&agent, &msg, buf, sizeof (buf), &msg);
finish_check (&agent, &msg);
if (memcmp (buf, "\x01\x01", 2))
fatal ("Response formatting test failed");
/* Error formatting test */
stun_agent_init_request (&agent, &msg, buf, sizeof(buf), STUN_BINDING);
finish_check (&agent, &msg);
if (!stun_agent_init_error (&agent, &msg, buf, sizeof (buf), &msg, 400))
fatal ("Error initialization test failed");
finish_check (&agent, &msg);
if (memcmp (buf, "\x01\x11", 2))
fatal ("Error formatting test failed");
/* Unknown error formatting test */
stun_agent_init_request (&agent, &msg, buf, sizeof(buf), STUN_BINDING);
finish_check (&agent, &msg);
if (!stun_agent_init_error (&agent, &msg, buf, sizeof (buf), &msg, 666))
fatal ("Unknown error initialization test failed");
finish_check (&agent, &msg);
if (memcmp (buf, "\x01\x11", 2))
fatal ("Unknown error formatting test failed");
/* Overflow tests */
stun_agent_init_request (&agent, &msg, buf, sizeof(buf), STUN_BINDING);
for (len = 0;
stun_message_append_flag (&msg, 0xffff) !=
STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE;
len += 4)
{
if (len > 0xffff)
fatal ("Overflow protection test failed");
}
if (stun_message_append32 (&msg, 0xffff, 0x12345678) !=
STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE)
fatal ("Double-word overflow test failed");
if (stun_message_append64 (&msg, 0xffff,
0x123456789abcdef0) != STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE)
fatal ("Quad-word overflow test failed");
if (stun_message_append_string (&msg, 0xffff, "foobar") !=
STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE)
fatal ("String overflow test failed");
memset (&addr, 0, sizeof (addr));
addr.sa_family = AF_INET;
#ifdef HAVE_SA_LEN
addr.sa_len = sizeof (addr);
#endif
if (stun_message_append_xor_addr (&msg, 0xffff, &addr,
sizeof (addr)) != STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE)
fatal ("Address overflow test failed");
len = sizeof (msg);
if (stun_agent_finish_message (&agent, &msg, NULL, 0) != 0)
fatal ("Fingerprint overflow test failed");
if (stun_agent_finish_message (&agent, &msg, pwd, strlen (pwd)) != 0)
fatal ("Message integrity overflow test failed");
/* Address attributes tests */
check_af ("IPv4", AF_INET, sizeof (struct sockaddr_in));
#ifdef AF_INET6
check_af ("IPv6", AF_INET6, sizeof (struct sockaddr_in6));
#endif
return 0;
}
StunUsageIceReturn
stun_usage_ice_conncheck_create_reply (StunAgent *agent, StunMessage *req,
StunMessage *msg, uint8_t *buf, size_t *plen,
const struct sockaddr_storage *src, socklen_t srclen,
bool *control, uint64_t tie,
StunUsageIceCompatibility compatibility)
{
const char *username = NULL;
uint16_t username_len;
size_t len = *plen;
uint64_t q;
StunMessageReturn val = STUN_MESSAGE_RETURN_SUCCESS;
StunUsageIceReturn ret = STUN_USAGE_ICE_RETURN_SUCCESS;
#define err( code ) \
stun_bind_error (agent, msg, buf, &len, req, code); \
*plen = len
*plen = 0;
stun_debug ("STUN Reply (buffer size = %u)...", (unsigned)len);
if (stun_message_get_class (req) != STUN_REQUEST)
{
stun_debug (" Unhandled non-request (class %u) message.",
stun_message_get_class (req));
return STUN_USAGE_ICE_RETURN_INVALID_REQUEST;
}
if (stun_message_get_method (req) != STUN_BINDING)
{
stun_debug (" Bad request (method %u) message.",
stun_message_get_method (req));
err (STUN_ERROR_BAD_REQUEST);
return STUN_USAGE_ICE_RETURN_INVALID_METHOD;
}
/* Role conflict handling */
assert (control != NULL);
if (stun_message_find64 (req, *control ? STUN_ATTRIBUTE_ICE_CONTROLLING
: STUN_ATTRIBUTE_ICE_CONTROLLED, &q) == STUN_MESSAGE_RETURN_SUCCESS)
{
/* we have the ice-controlling/controlled attribute,
* and there's a role conflict
*/
stun_debug ("STUN Role Conflict detected:");
/* According to ICE RFC 5245, section 7.2.1.1, we consider the four
* possible cases when a role conflict is detected: two cases are
* resolved by switching role locally, and the two other cases are
* handled by responding with a STUN error.
*/
if ((tie < q && *control) || (tie >= q && !*control))
{
stun_debug (" switching role from \"controll%s\" to \"controll%s\"",
*control ? "ing" : "ed", *control ? "ed" : "ing");
*control = !*control;
ret = STUN_USAGE_ICE_RETURN_ROLE_CONFLICT;
}
else
{
stun_debug (" staying \"controll%s\" (sending error)",
*control ? "ing" : "ed");
err (STUN_ERROR_ROLE_CONFLICT);
return STUN_USAGE_ICE_RETURN_ROLE_CONFLICT;
}
} else {
if (stun_message_find64 (req, *control ? STUN_ATTRIBUTE_ICE_CONTROLLED
: STUN_ATTRIBUTE_ICE_CONTROLLING, &q) != STUN_MESSAGE_RETURN_SUCCESS)
{
/* we don't have the expected ice-controlling/controlled
* attribute
*/
if (compatibility == STUN_USAGE_ICE_COMPATIBILITY_RFC5245 ||
compatibility == STUN_USAGE_ICE_COMPATIBILITY_MSICE2)
{
stun_debug ("STUN Role not specified by peer!");
}
}
}
if (stun_agent_init_response (agent, msg, buf, len, req) == FALSE) {
stun_debug ("Unable to create response");
goto failure;
}
if (compatibility == STUN_USAGE_ICE_COMPATIBILITY_MSN) {
union {
StunTransactionId transid;
uint32_t magic_cookie;
} conv;
stun_message_id (msg, conv.transid);
val = stun_message_append_xor_addr_full (msg, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
src, srclen, htonl (conv.magic_cookie));
} else if (stun_message_has_cookie (msg) &&
compatibility != STUN_USAGE_ICE_COMPATIBILITY_GOOGLE) {
val = stun_message_append_xor_addr (msg, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
src, srclen);
} else {
val = stun_message_append_addr (msg, STUN_ATTRIBUTE_MAPPED_ADDRESS,
(struct sockaddr *) src, srclen);
}
if (val != STUN_MESSAGE_RETURN_SUCCESS) {
stun_debug (" Mapped address problem: %d", val);
goto failure;
}
username = (const char *)stun_message_find (req,
STUN_ATTRIBUTE_USERNAME, &username_len);
if (username) {
val = stun_message_append_bytes (msg, STUN_ATTRIBUTE_USERNAME,
username, username_len);
}
if (val != STUN_MESSAGE_RETURN_SUCCESS) {
stun_debug ("Error appending username: %d", val);
goto failure;
}
if (compatibility == STUN_USAGE_ICE_COMPATIBILITY_MSICE2) {
val = stun_message_append32 (msg,
STUN_ATTRIBUTE_MS_IMPLEMENTATION_VERSION, 2);
if (val != STUN_MESSAGE_RETURN_SUCCESS) {
stun_debug ("Error appending implementation version: %d", val);
goto failure;
}
}
/* the stun agent will automatically use the password of the request */
len = stun_agent_finish_message (agent, msg, NULL, 0);
if (len == 0)
goto failure;
*plen = len;
stun_debug (" All done (response size: %u)", (unsigned)len);
return ret;
failure:
assert (*plen == 0);
stun_debug (" Fatal error formatting Response: %d", val);
switch (val)
{
case STUN_MESSAGE_RETURN_NOT_ENOUGH_SPACE:
return STUN_USAGE_ICE_RETURN_MEMORY_ERROR;
case STUN_MESSAGE_RETURN_INVALID:
case STUN_MESSAGE_RETURN_UNSUPPORTED_ADDRESS:
return STUN_USAGE_ICE_RETURN_INVALID_ADDRESS;
case STUN_MESSAGE_RETURN_SUCCESS:
assert (0); /* shouldn’t be reached */
case STUN_MESSAGE_RETURN_NOT_FOUND:
default:
return STUN_USAGE_ICE_RETURN_ERROR;
}
}
int handle_stun(udp_conn* c, uint8_t *packet, size_t len) {
StunAgent agent;
StunValidationStatus status;
StunAgentUsageFlags flags;
StunMessage request;
StunMessage response;
int ret;
size_t output_size;
uint8_t output[1024];
flags = STUN_AGENT_USAGE_IGNORE_CREDENTIALS; // | STUN_AGENT_USAGE_USE_FINGERPRINT;
static const uint16_t attr[] = {
STUN_ATTRIBUTE_MAPPED_ADDRESS,
STUN_ATTRIBUTE_RESPONSE_ADDRESS,
STUN_ATTRIBUTE_CHANGE_REQUEST,
STUN_ATTRIBUTE_SOURCE_ADDRESS,
STUN_ATTRIBUTE_CHANGED_ADDRESS,
STUN_ATTRIBUTE_USERNAME,
STUN_ATTRIBUTE_PASSWORD,
STUN_ATTRIBUTE_MESSAGE_INTEGRITY,
STUN_ATTRIBUTE_ERROR_CODE,
STUN_ATTRIBUTE_UNKNOWN_ATTRIBUTES,
STUN_ATTRIBUTE_REFLECTED_FROM,
STUN_ATTRIBUTE_CHANNEL_NUMBER,
STUN_ATTRIBUTE_LIFETIME,
STUN_ATTRIBUTE_MS_ALTERNATE_SERVER,
STUN_ATTRIBUTE_MAGIC_COOKIE,
STUN_ATTRIBUTE_BANDWIDTH,
STUN_ATTRIBUTE_DESTINATION_ADDRESS,
STUN_ATTRIBUTE_REMOTE_ADDRESS,
STUN_ATTRIBUTE_PEER_ADDRESS,
STUN_ATTRIBUTE_XOR_PEER_ADDRESS,
STUN_ATTRIBUTE_DATA,
STUN_ATTRIBUTE_REALM,
STUN_ATTRIBUTE_NONCE,
STUN_ATTRIBUTE_RELAY_ADDRESS,
STUN_ATTRIBUTE_RELAYED_ADDRESS,
STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS,
STUN_ATTRIBUTE_REQUESTED_ADDRESS_TYPE,
STUN_ATTRIBUTE_REQUESTED_PORT_PROPS,
STUN_ATTRIBUTE_REQUESTED_PROPS,
STUN_ATTRIBUTE_EVEN_PORT,
STUN_ATTRIBUTE_REQUESTED_TRANSPORT,
STUN_ATTRIBUTE_DONT_FRAGMENT,
STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
STUN_ATTRIBUTE_TIMER_VAL,
STUN_ATTRIBUTE_REQUESTED_IP,
STUN_ATTRIBUTE_RESERVATION_TOKEN,
STUN_ATTRIBUTE_CONNECT_STAT,
STUN_ATTRIBUTE_PRIORITY,
STUN_ATTRIBUTE_USE_CANDIDATE,
STUN_ATTRIBUTE_OPTIONS,
STUN_ATTRIBUTE_MS_VERSION,
STUN_ATTRIBUTE_SOFTWARE,
STUN_ATTRIBUTE_ALTERNATE_SERVER,
STUN_ATTRIBUTE_FINGERPRINT,
STUN_ATTRIBUTE_ICE_CONTROLLED,
STUN_ATTRIBUTE_ICE_CONTROLLING,
STUN_ATTRIBUTE_MS_SEQUENCE_NUMBER,
STUN_ATTRIBUTE_CANDIDATE_IDENTIFIER
};
/* initialize our agent to be compatible with RFC5389 (= with TLS support) */
output_size = 0;
memset(output, 0, sizeof(output));
stun_agent_init(&agent, attr, STUN_COMPATIBILITY_RFC5389, flags);
/* validate the request */
status = stun_agent_validate(&agent, &request, packet, len, NULL, NULL);
print_stun_validation_status(status);
/* check the class */
StunClass request_class = stun_message_get_class(&request);
print_stun_class(request_class);
if(request_class == STUN_ERROR) {
printf("Error: request stun class failed.\n");
exit(0);
}
/* what stun method? */
StunMethod request_method = stun_message_get_method(&request);
print_stun_method(request_method);
/* initialize the response */
ret = stun_agent_init_response(&agent, &response, output, 1024, &request);
printf("Stun agent_init_response ret: %d\n", ret);
/* add xor-mapped-address */
uint32_t magic_cookie = 0;
uint8_t* cookie_ptr = NULL;
StunTransactionId transid;
socklen_t sock_len = 0;
char client_ip[16] = { 0 } ;
StunMessageReturn stun_ret = STUN_MESSAGE_RETURN_INVALID;
stun_message_id(&response, transid);
magic_cookie = *((uint32_t*)transid);
sock_len = sizeof(c->client);
cookie_ptr = (uint8_t*) &magic_cookie;
inet_ntop(AF_INET, &c->client.sin_addr.s_addr, client_ip, sizeof(client_ip));
stun_ret = stun_message_append_xor_addr(&response, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS, (const struct sockaddr*)&c->client, sock_len);
print_stun_message_return(stun_ret);
printf("Received data from: %s\n", client_ip);
printf("Magic cookie: %02X %02X %02X %02X\n", cookie_ptr[0], cookie_ptr[1], cookie_ptr[2], cookie_ptr[3]);
// username
// --------
const char* username = NULL;
uint16_t username_len = 0;
username = (const char*)stun_message_find(&request, STUN_ATTRIBUTE_USERNAME, &username_len);
printf("Username: %s, len: %d\n", username, (int)username_len);
#if 0
if(username) {
StunMessageReturn username_res = stun_message_append_bytes(&response, STUN_ATTRIBUTE_USERNAME, username, username_len);
print_stun_message_return(username_res);
}
uint32_t fingerprint = 0;
if(stun_message_find32(&request, STUN_ATTRIBUTE_FINGERPRINT, &fingerprint) == STUN_MESSAGE_RETURN_SUCCESS) {
printf("Got fingerprint: %d\n", fingerprint);
if(stun_message_append32(&response, STUN_ATTRIBUTE_FINGERPRINT, fingerprint) != STUN_MESSAGE_RETURN_SUCCESS) {
printf("Error while adding the fingerprint.\n");
}
}
#endif
// password
const char* password = ucon_ptr->stun_pw; // "94ccca06d14fb48c135bdaff30560c4d";
uint16_t password_len = strlen(password) + 1;
output_size = stun_agent_finish_message(&agent, &response, (const uint8_t*) password, password_len);
// answer to the connection
krx_udp_send(c, output, output_size);
print_buffer(output, output_size);
return 0;
}
int main (void)
{
union {
struct sockaddr sa;
struct sockaddr_storage storage;
struct sockaddr_in ip4;
} addr;
uint8_t req_buf[STUN_MAX_MESSAGE_SIZE];
uint8_t resp_buf[STUN_MAX_MESSAGE_SIZE];
const const uint64_t tie = 0x8000000000000000LL;
StunMessageReturn val;
StunUsageIceReturn val2;
size_t len;
size_t rlen;
static char username[] = "L:R";
static uint8_t ufrag[] = "L", pass[] = "secret";
size_t ufrag_len = strlen ((char*) ufrag);
size_t pass_len = strlen ((char*) pass);
int code;
bool control = false;
StunAgent agent;
StunMessage req;
StunMessage resp;
StunDefaultValidaterData validater_data[] = {
{ufrag, ufrag_len, pass, pass_len},
{(uint8_t *) username, strlen (username), pass, pass_len},
{NULL, 0, NULL, 0}};
StunValidationStatus valid;
stun_agent_init (&agent, STUN_ALL_KNOWN_ATTRIBUTES,
STUN_COMPATIBILITY_RFC5389,
STUN_AGENT_USAGE_USE_FINGERPRINT |
STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS);
memset (&addr, 0, sizeof (addr));
addr.ip4.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
addr.ip4.sin_len = sizeof (addr);
#endif
addr.ip4.sin_port = htons (12345);
addr.ip4.sin_addr.s_addr = htonl (0x7f000001);
/* Incorrect message class */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
assert (stun_agent_init_response (&agent, &req, req_buf, sizeof (req_buf), &req));
rlen = stun_agent_finish_message (&agent, &req, NULL, 0);
assert (rlen > 0);
len = sizeof (resp_buf);
val2 = stun_usage_ice_conncheck_create_reply (&agent, &req,
&resp, resp_buf, &len, &addr.storage,
sizeof (addr.ip4), &control, tie, STUN_USAGE_ICE_COMPATIBILITY_RFC5245);
assert (val2 == STUN_USAGE_ICE_RETURN_INVALID_REQUEST);
assert (len == 0);
/* Incorrect message method */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), 0x666));
val = stun_message_append_string (&req, STUN_ATTRIBUTE_USERNAME, username);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
len = sizeof (resp_buf);
val2 = stun_usage_ice_conncheck_create_reply (&agent, &req,
&resp, resp_buf, &len, &addr.storage,
sizeof (addr.ip4), &control, tie, STUN_USAGE_ICE_COMPATIBILITY_RFC5245);
assert (val2 == STUN_USAGE_ICE_RETURN_INVALID_METHOD);
assert (len > 0);
/* Unknown attribute */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
val = stun_message_append_string (&req, 0x666, "The evil unknown attribute!");
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
val = stun_message_append_string (&req, STUN_ATTRIBUTE_USERNAME, username);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
valid = stun_agent_validate (&agent, &req, req_buf, rlen,
stun_agent_default_validater, validater_data);
assert (valid == STUN_VALIDATION_UNKNOWN_REQUEST_ATTRIBUTE);
/* Unauthenticated message */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
rlen = stun_agent_finish_message (&agent, &req, NULL, 0);
assert (rlen > 0);
valid = stun_agent_validate (&agent, &req, req_buf, rlen,
stun_agent_default_validater, validater_data);
assert (valid == STUN_VALIDATION_UNAUTHORIZED_BAD_REQUEST);
/* No username */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
valid = stun_agent_validate (&agent, &req, req_buf, rlen,
stun_agent_default_validater, validater_data);
assert (valid == STUN_VALIDATION_UNAUTHORIZED_BAD_REQUEST);
assert (stun_usage_ice_conncheck_priority (&req) == 0);
assert (stun_usage_ice_conncheck_use_candidate (&req) == false);
/* Good message */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
val = stun_message_append32 (&req, STUN_ATTRIBUTE_PRIORITY, 0x12345678);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
val = stun_message_append_flag (&req, STUN_ATTRIBUTE_USE_CANDIDATE);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
val = stun_message_append_string (&req, STUN_ATTRIBUTE_USERNAME,
(char*) ufrag);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
len = sizeof (resp_buf);
val2 = stun_usage_ice_conncheck_create_reply (&agent, &req,
&resp, resp_buf, &len, &addr.storage,
sizeof (addr.ip4), &control, tie, STUN_USAGE_ICE_COMPATIBILITY_RFC5245);
assert (val2 == STUN_USAGE_ICE_RETURN_SUCCESS);
assert (len > 0);
assert (stun_agent_validate (&agent, &resp, resp_buf, len,
stun_agent_default_validater, validater_data) == STUN_VALIDATION_SUCCESS);
assert (stun_message_get_class (&resp) == STUN_RESPONSE);
assert (stun_usage_ice_conncheck_priority (&req) == 0x12345678);
assert (stun_usage_ice_conncheck_use_candidate (&req) == true);
/* Invalid socket address */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
val = stun_message_append_string (&req, STUN_ATTRIBUTE_USERNAME, ufrag);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
addr.ip4.sin_family = AF_UNSPEC;
len = sizeof (resp_buf);
val2 = stun_usage_ice_conncheck_create_reply (&agent, &req,
&resp, resp_buf, &len, &addr.storage,
sizeof (addr.ip4), &control, tie, STUN_USAGE_ICE_COMPATIBILITY_RFC5245);
assert (val2 == STUN_USAGE_ICE_RETURN_INVALID_ADDRESS);
assert (len == 0);
addr.ip4.sin_family = AF_INET;
/* Lost role conflict */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
val = stun_message_append64 (&req, STUN_ATTRIBUTE_ICE_CONTROLLING, tie + 1);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
val = stun_message_append_string (&req, STUN_ATTRIBUTE_USERNAME, ufrag);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
len = sizeof (resp_buf);
control = true;
val2 = stun_usage_ice_conncheck_create_reply (&agent, &req,
&resp, resp_buf, &len, &addr.storage,
sizeof (addr.ip4), &control, tie, STUN_USAGE_ICE_COMPATIBILITY_RFC5245);
assert (val2 == STUN_USAGE_ICE_RETURN_ROLE_CONFLICT);
assert (len > 0);
assert (control == false);
assert (stun_agent_validate (&agent, &resp, resp_buf, len,
stun_agent_default_validater, validater_data) == STUN_VALIDATION_SUCCESS);
assert (stun_message_get_class (&resp) == STUN_RESPONSE);
/* Won role conflict */
assert (stun_agent_init_request (&agent, &req, req_buf, sizeof(req_buf), STUN_BINDING));
val = stun_message_append64 (&req, STUN_ATTRIBUTE_ICE_CONTROLLED, tie - 1);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
val = stun_message_append_string (&req, STUN_ATTRIBUTE_USERNAME, ufrag);
assert (val == STUN_MESSAGE_RETURN_SUCCESS);
rlen = stun_agent_finish_message (&agent, &req, pass, pass_len);
assert (rlen > 0);
len = sizeof (resp_buf);
control = false;
val2 = stun_usage_ice_conncheck_create_reply (&agent, &req,
&resp, resp_buf, &len, &addr.storage,
sizeof (addr.ip4), &control, tie, STUN_USAGE_ICE_COMPATIBILITY_RFC5245);
assert (val2 == STUN_USAGE_ICE_RETURN_SUCCESS);
assert (len > 0);
assert (control == false);
assert (stun_agent_validate (&agent, &resp, resp_buf, len,
stun_agent_default_validater, validater_data) == STUN_VALIDATION_SUCCESS);
assert (stun_message_get_class (&resp) == STUN_ERROR);
stun_message_find_error (&resp, &code);
assert (code == STUN_ERROR_ROLE_CONFLICT);
return 0;
}