support mki value

Add support mki value in the DTLS-SRTP

Signed-off-by: Johan Pascal <johan.pascal@belledonne-communications.com>
This commit is contained in:
Ron Eldor 2018-01-22 12:30:04 +02:00 committed by Johan Pascal
parent 3adb9928f3
commit 591f162bed
4 changed files with 168 additions and 61 deletions

View file

@ -214,6 +214,9 @@
#define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1
#define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0
#define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED 0
#define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED 1
/*
* Default range for DTLS retransmission timer value, in milliseconds.
* RFC 6347 4.2.4.1 says from 1 second to 60 seconds.
@ -1182,7 +1185,7 @@ struct mbedtls_ssl_config
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_SSL_DTLS_SRTP)
unsigned int dtls_srtp_mki_support : 1; /* support having mki_value
in the use_srtp extension */
in the use_srtp extension */
#endif
};
@ -3174,6 +3177,16 @@ const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_ALPN */
#if defined(MBEDTLS_SSL_DTLS_SRTP)
/**
* \brief Add support for mki value in use_srtp extension
* (Default: MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED)
*
* \param conf SSL configuration
* \param truncate Enable or disable (MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED or
* MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED)
*/
void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf, int support_mki_value );
/**
* \brief Set the supported DTLS-SRTP protection profiles.
*
@ -3185,6 +3198,17 @@ const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
* \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA.
*/
int mbedtls_ssl_conf_dtls_srtp_protection_profiles( mbedtls_ssl_config *conf, const mbedtls_ssl_srtp_profile *profiles, size_t profiles_number);
/**
* \brief Set the mki_value for the current dtls session.
*
* \param ssl SSL context
* \param mki_value MKI value to set
* \param mki_len MKI length
*
* \return 0 on success, MBEDTLS_ERR_SSL_BAD_INPUT_DATA or MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
*/
int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl, unsigned char* mki_value, size_t mki_len );
/**
* \brief Get the negotiated DTLS-SRTP Protection Profile.
* This function should be called after the handshake is
@ -3194,7 +3218,7 @@ int mbedtls_ssl_conf_dtls_srtp_protection_profiles( mbedtls_ssl_config *conf, co
*
* \return Protection Profile enum member, MBEDTLS_SRTP_UNSET_PROFILE if no protocol was negotiated.
*/
mbedtls_ssl_srtp_profile mbedtls_ssl_get_dtls_srtp_protection_profile( const mbedtls_ssl_context *ssl);
mbedtls_ssl_srtp_profile mbedtls_ssl_get_dtls_srtp_protection_profile( const mbedtls_ssl_context *ssl );
/**
* \brief Get the generated DTLS-SRTP key material.

View file

@ -762,6 +762,7 @@ static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
{
unsigned char *p = buf;
size_t protection_profiles_index = 0;
size_t mki_len = 0, i;
*olen = 0;
@ -785,12 +786,15 @@ static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
*
* Note: srtp_mki is not supported
*/
/* Extension length = 2bytes for profiles lenght, ssl->conf->dtls_srtp_profile_list_len*2 (each profile is 2 bytes length ) + 1 byte for the non implemented srtp_mki vector length (always 0) */
*p++ = (unsigned char)( ( ( 2 + 2*(ssl->conf->dtls_srtp_profile_list_len) + 1 ) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ( 2 + 2*(ssl->conf->dtls_srtp_profile_list_len) + 1 ) ) & 0xFF );
if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED &&
ssl->dtls_srtp_info.mki_len != 0 )
{
mki_len = ssl->dtls_srtp_info.mki_len;
}
/* Extension length = 2bytes for profiles length, ssl->conf->dtls_srtp_profile_list_len*2 (each profile is 2 bytes length ) + 1 byte for srtp_mki vector length and the mki_len value */
*p++ = (unsigned char)( ( ( 2 + 2*(ssl->conf->dtls_srtp_profile_list_len) + 1 + mki_len ) >> 8 ) & 0xFF );
*p++ = (unsigned char)( ( ( 2 + 2*(ssl->conf->dtls_srtp_profile_list_len) + 1 + mki_len ) ) & 0xFF );
/* protection profile length: 2*(ssl->conf->dtls_srtp_profile_list_len) */
@ -831,9 +835,18 @@ static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
}
}
*p++ = 0x00; /* non implemented srtp_mki vector length is always 0 */
*p++ = mki_len & 0xFF;
if( mki_len != 0 )
{
for( i=0; i < mki_len; i++ )
{
*p++ = ssl->dtls_srtp_info.mki_value[i];
}
}
/* total extension length: extension type (2 bytes) + extension length (2 bytes) + protection profile length (2 bytes) + 2*nb protection profiles + srtp_mki vector length(1 byte)*/
*olen = 2 + 2 + 2 + 2*(ssl->conf->dtls_srtp_profile_list_len) + 1;
*olen = 2 + 2 + 2 + 2*( ssl->conf->dtls_srtp_profile_list_len ) + 1 + mki_len;
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */
@ -1804,7 +1817,7 @@ static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
{
mbedtls_ssl_srtp_profile server_protection = MBEDTLS_SRTP_UNSET_PROFILE;
size_t i;
size_t i, mki_len = 0;
uint16_t server_protection_profile_value = 0;
/* If use_srtp is not configured, just ignore the extension */
@ -1821,22 +1834,28 @@ static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
*
* Note: srtp_mki is not supported
*/
if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED &&
ssl->dtls_srtp_info.mki_len != 0 )
{
mki_len = ssl->dtls_srtp_info.mki_len;
}
/* Length is 5 : one protection profile(2 bytes) + length(2 bytes) and potential srtp_mki which won't be parsed */
if( len < 5 )
/* Length is 5 and optional mki_value : one protection profile(2 bytes) + length(2 bytes) and srtp_mki */
if( ( len != 5 ) && ( len != ( 5 + mki_len ) ) )
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
/*
* get the server protection profile
*/
if (((uint16_t)(buf[0]<<8 | buf[1])) != 0x0002) { /* protection profile length must be 0x0002 as we must have only one protection profile in server Hello */
if (((uint16_t)( ( buf[0]<<8 ) | buf[1] ) ) != 0x0002) { /* protection profile length must be 0x0002 as we must have only one protection profile in server Hello */
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
} else {
server_protection_profile_value = buf[2]<<8 | buf[3];
server_protection_profile_value = ( buf[2]<<8 ) | buf[3];
}
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_SRTP_UNSET_PROFILE;
/*
* Check we have the server profile in our list
*/
@ -1862,15 +1881,30 @@ static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
if (server_protection == ssl->conf->dtls_srtp_profile_list[i]) {
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = ssl->conf->dtls_srtp_profile_list[i];
return 0;
break;
}
}
/* If we get there, no match was found : server problem, it shall never answer with incompatible profile */
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_SRTP_UNSET_PROFILE;
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
/* If no match was found : server problem, it shall never answer with incompatible profile */
if( ssl->dtls_srtp_info.chosen_dtls_srtp_profile == MBEDTLS_SRTP_UNSET_PROFILE )
{
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
/* RFC5764:
* If the client detects a nonzero-length MKI in the server's response
* that is different than the one the client offered, then the client
* MUST abort the handshake and SHOULD send an invalid_parameter alert.
*/
if( len > 5 &&
( memcmp( ssl->dtls_srtp_info.mki_value, &buf[5], mki_len ) ) )
{
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER );
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
return 0;
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */

View file

@ -782,7 +782,7 @@ static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
{
mbedtls_ssl_srtp_profile client_protection = MBEDTLS_SRTP_UNSET_PROFILE;
size_t i,j;
uint16_t profile_length;
size_t profile_length;
/* If use_srtp is not configured, just ignore the extension */
if( ( ssl->conf->dtls_srtp_profile_list == NULL ) || ( ssl->conf->dtls_srtp_profile_list_len == 0 ) )
@ -798,53 +798,71 @@ static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
*
* Note: srtp_mki is not supported
*/
/* Min length is 5 : at least one protection profile(2 bytes) and length(2 bytes) + srtp_mki length(1 byte) */
if( len < 5 )
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
/*
* Use our order of preference
*/
profile_length = buf[0]<<8|buf[1]; /* first 2 bytes are protection profile length(in bytes) */
for( i=0; i < ssl->conf->dtls_srtp_profile_list_len; i++)
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_SRTP_UNSET_PROFILE;
profile_length = ( buf[0]<<8 ) | buf[1]; /* first 2 bytes are protection profile length(in bytes) */
/* parse the extension list values are defined in http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml */
for( j=0; j < profile_length; j+=2 )
{
/* parse the extension list values are defined in http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml */
for (j=0; j<profile_length; j+=2) { /* parse only the protection profile, srtp_mki is not supported and ignored */
uint16_t protection_profile_value = buf[j+2]<<8 | buf[j+3]; /* +2 to skip the length field */
uint16_t protection_profile_value = buf[j+2]<<8 | buf[j+3]; /* +2 to skip the length field */
switch ( protection_profile_value ) {
case MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_80_IANA_VALUE:
client_protection = MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_80;
break;
case MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_32_IANA_VALUE:
client_protection = MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_32;
break;
case MBEDTLS_SRTP_NULL_HMAC_SHA1_80_IANA_VALUE:
client_protection = MBEDTLS_SRTP_NULL_HMAC_SHA1_80;
break;
case MBEDTLS_SRTP_NULL_HMAC_SHA1_32_IANA_VALUE:
client_protection = MBEDTLS_SRTP_NULL_HMAC_SHA1_32;
break;
default:
client_protection = MBEDTLS_SRTP_UNSET_PROFILE;
break;
}
if (client_protection == ssl->conf->dtls_srtp_profile_list[i]) {
switch ( protection_profile_value )
{
case MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_80_IANA_VALUE:
client_protection = MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_80;
break;
case MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_32_IANA_VALUE:
client_protection = MBEDTLS_SRTP_AES128_CM_HMAC_SHA1_32;
break;
case MBEDTLS_SRTP_NULL_HMAC_SHA1_80_IANA_VALUE:
client_protection = MBEDTLS_SRTP_NULL_HMAC_SHA1_80;
break;
case MBEDTLS_SRTP_NULL_HMAC_SHA1_32_IANA_VALUE:
client_protection = MBEDTLS_SRTP_NULL_HMAC_SHA1_32;
break;
default:
client_protection = MBEDTLS_SRTP_UNSET_PROFILE;
break;
}
/* check if suggested profile is in our list */
for( i=0; i < ssl->conf->dtls_srtp_profile_list_len; i++)
{
if( client_protection == ssl->conf->dtls_srtp_profile_list[i] )
{
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = ssl->conf->dtls_srtp_profile_list[i];
return 0;
break;
}
}
if( ssl->dtls_srtp_info.chosen_dtls_srtp_profile != MBEDTLS_SRTP_UNSET_PROFILE )
break;
}
if( ( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED ) &&
( len > ( profile_length + 2 ) ) )
{
ssl->dtls_srtp_info.mki_len = buf[ profile_length + 2 ];
if( ssl->dtls_srtp_info.mki_len > MBEDTLS_DTLS_SRTP_MAX_MKI_LENGTH )
{
mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
ssl->dtls_srtp_info.mki_len = 0;
return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
}
for( i=0; i < ssl->dtls_srtp_info.mki_len; i++ )
{
ssl->dtls_srtp_info.mki_value[i] = buf[ profile_length + 2 + i ];
}
}
/* If we get there, no match was found */
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_SRTP_UNSET_PROFILE;
// mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
// MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
return( 0 );
return( 0 );
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */
@ -2585,6 +2603,8 @@ static void ssl_write_alpn_ext( mbedtls_ssl_context *ssl,
static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
unsigned char *buf, size_t *olen )
{
size_t mki_len = 0, ext_len = 0, i;
if( ssl->dtls_srtp_info.chosen_dtls_srtp_profile == MBEDTLS_SRTP_UNSET_PROFILE )
{
*olen = 0;
@ -2593,12 +2613,19 @@ static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding use_srtp extension" ) );
if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED &&
ssl->dtls_srtp_info.mki_len != 0 )
{
mki_len = ssl->dtls_srtp_info.mki_len;
}
/* extension */
buf[0] = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP >> 8 ) & 0xFF );
buf[1] = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP ) & 0xFF );
/* total length (5: only one profile(2 bytes) and length(2bytes) and srtp_mki not supported so zero length(1byte) ) */
buf[2] = 0x00;
buf[3] = 0x05;
/* total length 5 and mki value: only one profile(2 bytes) and length(2 bytes) and srtp_mki ) */
ext_len = 5 + mki_len;
buf[2] = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
buf[3] = (unsigned char)( ext_len & 0xFF );
/* protection profile length: 2 */
buf[4] = 0x00;
@ -2625,9 +2652,13 @@ static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
return;
}
buf[8] = 0x00; /* unsupported srtp_mki variable length vector set to 0 */
buf[8] = mki_len & 0xFF;
for( i=0; i < mki_len; i++ )
{
buf[ 9 + i ] = ssl->dtls_srtp_info.mki_value[i];
}
*olen = 9;
*olen = 9 + mki_len;
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */

View file

@ -4714,6 +4714,24 @@ const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl )
#endif /* MBEDTLS_SSL_ALPN */
#if defined(MBEDTLS_SSL_DTLS_SRTP)
void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf, int support_mki_value )
{
conf->dtls_srtp_mki_support = support_mki_value;
}
int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl, unsigned char* mki_value, size_t mki_len )
{
if ( mki_len > MBEDTLS_DTLS_SRTP_MAX_MKI_LENGTH )
return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED )
return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
memcpy( ssl->dtls_srtp_info.mki_value, mki_value, mki_len );
ssl->dtls_srtp_info.mki_len = mki_len;
return 0;
}
int mbedtls_ssl_conf_dtls_srtp_protection_profiles( mbedtls_ssl_config *conf, const mbedtls_ssl_srtp_profile *profiles, size_t profiles_number)
{
size_t i;