/*
* add_fingerprint()
* - msg: response buffer
*
* The function add_fingerprint ensures adding fingerprint attribute into
* response buffer.
*
* Return value: 0 if there is no environment error
* -1 if there is some enviroment error such as insufficiency
* of memory
*/
int add_fingerprint(struct stun_buffer* msg)
{
struct stun_attr attr;
USHORT_T attr_type_size;
attr_type_size = sizeof(struct stun_attr);
attr.type = htons(FINGERPRINT_ATTR);
attr.len = htons(SHA_DIGEST_LENGTH);
if (msg->empty < (SHA_DIGEST_LENGTH + attr_type_size)) {
if (reallock_buffer(msg, SHA_DIGEST_LENGTH + attr_type_size) != 0) {
return FATAL_ERROR;
}
}
memcpy(&msg->buf.s[msg->buf.len], (void *) &attr, attr_type_size);
msg->buf.len += attr_type_size;
msg->empty -= attr_type_size;
if (SHA1((UCHAR_T *)msg->buf.s, msg->buf.len-attr_type_size,
(UCHAR_T *) &msg->buf.s[msg->buf.len]) == 0) {
LOG(L_ERR, "ERROR: STUN: SHA-1 algorithm failed.\n");
return FATAL_ERROR;
}
msg->buf.len += SHA_DIGEST_LENGTH;
msg->empty -= SHA_DIGEST_LENGTH;
return 0;
}
/*
* buf_copy()
* - msg: buffer where the data will be copy to
* - source: source data buffer
* - len: number of bytes that should be copied
*
* The function buf_copy copies "len" bytes from source into msg buffer
*
* Return value: 0 if there is no environment error
* -1 if there is some enviroment error such as insufficiency
* of memory
*/
static int buf_copy(struct stun_buffer* msg, void* source, UINT_T len)
{
if (msg->empty < len) {
if (reallock_buffer(msg, len) != 0) {
return FATAL_ERROR;
}
}
memcpy(&msg->buf.s[msg->buf.len], source, len);
msg->buf.len += len;
msg->empty -= len;
return 0;
}
/*
* add_error_code()
* - res: response representation
* - error_code: value of error type
*
* The function add_error_code ensures copy of link list of unknown
* attributes into response buffer.
*
* Return value: 0 if there is no environment error
* -1 if there is some enviroment error such as insufficiency
* of memory
*/
static int add_error_code(struct stun_msg* res, USHORT_T error_code)
{
struct stun_attr attr;
USHORT_T orig_len;
USHORT_T two_bytes;
int text_pad;
char err[2];
orig_len = res->msg.buf.len;
text_pad = 0;
/* the type and length will be copy as last one because of unknown length*/
if (res->msg.buf.len < sizeof(struct stun_attr)) {
if (reallock_buffer(&res->msg, sizeof(struct stun_attr)) != 0) {
#ifdef EXTRA_DEBUG
LOG(L_DBG, "DEBUG: add_error_code: failed to reallocate buffer\n");
#endif
return FATAL_ERROR;
}
}
res->msg.buf.len += sizeof(struct stun_attr);
res->msg.empty -= sizeof(struct stun_attr);
/* first two bytes are empty */
two_bytes = 0x0000;
if (buf_copy(&res->msg, (void *) &two_bytes, sizeof(USHORT_T)) != 0) {
#ifdef EXTRA_DEBUG
LOG(L_DBG, "DEBUG: add_error_code: failed to copy buffer\n");
#endif
return FATAL_ERROR;
}
err[0] = error_code / 100;
err[1] = error_code % 100;
if (buf_copy(&res->msg, (void *) err, sizeof(UCHAR_T)*2) != 0) {
return FATAL_ERROR;
}
switch (error_code) {
case TRY_ALTERNATE_ERR:
text_pad = copy_str_to_buffer(res, TRY_ALTERNATE_TXT, PAD4);
break;
case BAD_REQUEST_ERR:
text_pad = copy_str_to_buffer(res, BAD_REQUEST_TXT, PAD4);
break;
case UNAUTHORIZED_ERR:
text_pad = copy_str_to_buffer(res, UNAUTHORIZED_TXT, PAD4);
break;
case UNKNOWN_ATTRIBUTE_ERR:
text_pad = copy_str_to_buffer(res, UNKNOWN_ATTRIBUTE_TXT, PAD4);
break;
case STALE_CREDENTIALS_ERR:
text_pad = copy_str_to_buffer(res, STALE_CREDENTIALS_TXT, PAD4);
break;
case INTEGRITY_CHECK_ERR:
text_pad = copy_str_to_buffer(res, INTEGRITY_CHECK_TXT, PAD4);
break;
case MISSING_USERNAME_ERR:
text_pad = copy_str_to_buffer(res, MISSING_USERNAME_TXT, PAD4);
break;
case USE_TLS_ERR:
text_pad = copy_str_to_buffer(res, USE_TLS_TXT, PAD4);
break;
case MISSING_REALM_ERR:
text_pad = copy_str_to_buffer(res, MISSING_REALM_TXT, PAD4);
break;
case MISSING_NONCE_ERR:
text_pad = copy_str_to_buffer(res, MISSING_NONCE_TXT, PAD4);
break;
case UNKNOWN_USERNAME_ERR:
text_pad = copy_str_to_buffer(res, UNKNOWN_USERNAME_TXT, PAD4);
break;
case STALE_NONCE_ERR:
text_pad = copy_str_to_buffer(res, STALE_NONCE_TXT, PAD4);
break;
case SERVER_ERROR_ERR:
text_pad = copy_str_to_buffer(res, SERVER_ERROR_TXT, PAD4);
break;
case GLOBAL_FAILURE_ERR:
text_pad = copy_str_to_buffer(res, GLOBAL_FAILURE_TXT, PAD4);
break;
default:
LOG(L_ERR, "ERROR: STUN: Unknown error code.\n");
break;
}
if (text_pad < 0) {
#ifdef EXTRA_DEBUG
LOG(L_DBG, "DEBUG: add_error_code: text_pad is negative\n");
#endif
goto error;
}
attr.type = htons(ERROR_CODE_ATTR);
/* count length of "value" field -> without type and lehgth field */
attr.len = htons(res->msg.buf.len - orig_len -
text_pad - sizeof(struct stun_attr));
memcpy(&res->msg.buf.s[orig_len], (void *)&attr, sizeof(struct stun_attr));
return 0;
error:
return FATAL_ERROR;
}
