Add server support for ECDHE_ECDSA key exchange
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 17b23f1..f8e1748 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -912,6 +912,7 @@
int handshake_failure = 0;
const int *ciphersuites;
const ssl_ciphersuite_t *ciphersuite_info;
+ pk_type_t pk_alg;
SSL_DEBUG_MSG( 2, ( "=> parse client hello" ) );
@@ -1303,7 +1304,7 @@
if( ciphersuite_info == NULL )
{
- SSL_DEBUG_MSG( 1, ( "ciphersuite info for %02x not found",
+ SSL_DEBUG_MSG( 1, ( "ciphersuite info for %04x not found",
ciphersuites[i] ) );
return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
}
@@ -1318,8 +1319,12 @@
continue;
#endif
- if( ciphersuite_info->key_exchange ==
- POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA )
+ /* If ciphersuite requires us to have a private key of a
+ * certain type, make sure we do */
+ pk_alg = ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info );
+ if( pk_alg != POLARSSL_PK_NONE &&
+ ( ssl->pk_key == NULL ||
+ ! pk_can_do( ssl->pk_key, pk_alg ) ) )
continue;
goto have_ciphersuite;
@@ -1823,10 +1828,10 @@
size_t n = 0, len;
unsigned char hash[64];
md_type_t md_alg = POLARSSL_MD_NONE;
- unsigned int hashlen = 0;
+ unsigned int hashlen;
unsigned char *p = ssl->out_msg + 4;
- unsigned char *dig_sig = p;
- size_t dig_sig_len = 0;
+ unsigned char *dig_signed = p;
+ size_t dig_signed_len = 0;
const ssl_ciphersuite_t *ciphersuite_info;
ciphersuite_info = ssl->transform_negotiate->ciphersuite_info;
@@ -1835,6 +1840,7 @@
if( ciphersuite_info->key_exchange != POLARSSL_KEY_EXCHANGE_DHE_RSA &&
ciphersuite_info->key_exchange != POLARSSL_KEY_EXCHANGE_ECDHE_RSA &&
+ ciphersuite_info->key_exchange != POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA &&
ciphersuite_info->key_exchange != POLARSSL_KEY_EXCHANGE_DHE_PSK )
{
SSL_DEBUG_MSG( 2, ( "<= skip write server key exchange" ) );
@@ -1842,14 +1848,6 @@
return( 0 );
}
-#if defined(POLARSSL_RSA_C)
- if( ssl->rsa_key == NULL )
- {
- SSL_DEBUG_MSG( 1, ( "got no private key" ) );
- return( POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED );
- }
-#endif /* POLARSSL_RSA_C */
-
#if defined(POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_DHE_PSK )
{
@@ -1891,8 +1889,8 @@
return( ret );
}
- dig_sig = p;
- dig_sig_len = len;
+ dig_signed = p;
+ dig_signed_len = len;
p += len;
n += len;
@@ -1905,8 +1903,10 @@
#endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_DHE_PSK_ENABLED */
-#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED)
- if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA )
+#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
+ defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
+ if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA ||
+ ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA )
{
/*
* Ephemeral ECDH parameters:
@@ -1932,23 +1932,29 @@
return( ret );
}
- dig_sig = p;
- dig_sig_len = len;
+ dig_signed = p;
+ dig_signed_len = len;
p += len;
n += len;
SSL_DEBUG_ECP( 3, "ECDH: Q ", &ssl->handshake->ecdh_ctx.Q );
}
-#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED */
+#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
+ POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
- defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED)
+ defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
+ defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_DHE_RSA ||
- ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA )
+ ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA ||
+ ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA )
{
- size_t rsa_key_len = 0;
+ size_t signature_len = 0;
+ /*
+ * Compute the hash to be signed
+ */
if( ssl->minor_ver != SSL_MINOR_VERSION_3 )
{
md5_context md5;
@@ -1969,12 +1975,12 @@
*/
md5_starts( &md5 );
md5_update( &md5, ssl->handshake->randbytes, 64 );
- md5_update( &md5, dig_sig, dig_sig_len );
+ md5_update( &md5, dig_signed, dig_signed_len );
md5_finish( &md5, hash );
sha1_starts( &sha1 );
sha1_update( &sha1, ssl->handshake->randbytes, 64 );
- sha1_update( &sha1, dig_sig, dig_sig_len );
+ sha1_update( &sha1, dig_signed, dig_signed_len );
sha1_finish( &sha1, hash + 16 );
hashlen = 36;
@@ -1983,6 +1989,7 @@
else
{
md_context_t ctx;
+ const md_info_t *md_info;
/*
* digitally-signed struct {
@@ -2024,7 +2031,15 @@
return( -1 );
}
- if( ( ret = md_init_ctx( &ctx, md_info_from_type( md_alg ) ) ) != 0 )
+ if( ( md_info = md_info_from_type( md_alg ) ) == NULL )
+ {
+ SSL_DEBUG_MSG( 1, ( "should never happen" ) );
+ return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
+ }
+
+ hashlen = md_info->size;
+
+ if( ( ret = md_init_ctx( &ctx, md_info ) ) != 0 )
{
SSL_DEBUG_RET( 1, "md_init_ctx", ret );
return( ret );
@@ -2032,7 +2047,7 @@
md_starts( &ctx );
md_update( &ctx, ssl->handshake->randbytes, 64 );
- md_update( &ctx, dig_sig, dig_sig_len );
+ md_update( &ctx, dig_signed, dig_signed_len );
md_finish( &ctx, hash );
if( ( ret = md_free_ctx( &ctx ) ) != 0 )
@@ -2045,40 +2060,82 @@
SSL_DEBUG_BUF( 3, "parameters hash", hash, hashlen );
- if ( ssl->rsa_key )
- rsa_key_len = ssl->rsa_key_len( ssl->rsa_key );
-
- if( ssl->minor_ver == SSL_MINOR_VERSION_3 )
+ /*
+ * Make the signature
+ */
+ if( ssl->pk_key == NULL || ssl->pk_key->pk_info == NULL )
{
- *(p++) = ssl->handshake->sig_alg;
- *(p++) = SSL_SIG_RSA;
-
- n += 2;
+ SSL_DEBUG_MSG( 1, ( "got no private key" ) );
+ return( POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED );
}
- *(p++) = (unsigned char)( rsa_key_len >> 8 );
- *(p++) = (unsigned char)( rsa_key_len );
+#if defined(POLARSSL_RSA_C)
+ if( ssl->rsa_key != NULL )
+ {
+ if( ssl->minor_ver == SSL_MINOR_VERSION_3 )
+ {
+ *(p++) = ssl->handshake->sig_alg;
+ *(p++) = SSL_SIG_RSA;
+
+ n += 2;
+ }
+
+ if( ( ret = ssl->rsa_sign( ssl->rsa_key, ssl->f_rng, ssl->p_rng,
+ RSA_PRIVATE, md_alg, hashlen, hash, p + 2 ) ) != 0 )
+ {
+ SSL_DEBUG_RET( 1, "rsa_sign", ret );
+ return( ret );
+ }
+
+ signature_len = ssl->rsa_key_len( ssl->rsa_key );
+ }
+ else
+#endif /* POLARSSL_RSA_C */
+#if defined(POLARSSL_ECDSA_C)
+ if( pk_can_do( ssl->pk_key, POLARSSL_PK_ECDSA ) )
+ {
+ ecdsa_context ecdsa;
+
+ if( ssl->minor_ver == SSL_MINOR_VERSION_3 )
+ {
+ *(p++) = ssl->handshake->sig_alg;
+ *(p++) = SSL_SIG_ECDSA;
+
+ n += 2;
+ }
+
+ ecdsa_init( &ecdsa );
+
+ ret = ecdsa_from_keypair( &ecdsa, ssl->pk_key->pk_ctx ) ||
+ ecdsa_write_signature( &ecdsa, hash, hashlen,
+ p + 2, &signature_len,
+ ssl->f_rng, ssl->p_rng );
+
+ ecdsa_free( &ecdsa );
+
+ if( ret != 0 )
+ {
+ SSL_DEBUG_RET( 1, "ecdsa_sign", ret );
+ return( ret );
+ }
+ }
+ else
+#endif /* POLARSSL_ECDSA_C */
+ /* should never happen */
+ return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
+
+ *(p++) = (unsigned char)( signature_len >> 8 );
+ *(p++) = (unsigned char)( signature_len );
n += 2;
- if ( ssl->rsa_key )
- {
- ret = ssl->rsa_sign( ssl->rsa_key, ssl->f_rng, ssl->p_rng,
- RSA_PRIVATE, md_alg, hashlen, hash, p );
- }
+ SSL_DEBUG_BUF( 3, "my signature", p, signature_len );
- if( ret != 0 )
- {
- SSL_DEBUG_RET( 1, "pkcs1_sign", ret );
- return( ret );
- }
-
- SSL_DEBUG_BUF( 3, "my RSA sig", p, rsa_key_len );
-
- p += rsa_key_len;
- n += rsa_key_len;
+ p += signature_len;
+ n += signature_len;
}
#endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED) ||
- POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED */
+ POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
+ POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
ssl->out_msglen = 4 + n;
ssl->out_msgtype = SSL_MSG_HANDSHAKE;
@@ -2362,8 +2419,10 @@
}
else
#endif /* POLARSSL_KEY_EXCHANGE_DHE_RSA_ENABLED */
-#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED)
- if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA )
+#if defined(POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
+ defined(POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
+ if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_RSA ||
+ ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA )
{
if( ( ret = ssl_parse_client_ecdh_public( ssl ) ) != 0 )
{
@@ -2383,7 +2442,8 @@
SSL_DEBUG_MPI( 3, "ECDH: z ", &ssl->handshake->ecdh_ctx.z );
}
else
-#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED */
+#endif /* POLARSSL_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
+ POLARSSL_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#if defined(POLARSSL_KEY_EXCHANGE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == POLARSSL_KEY_EXCHANGE_PSK )
{
@@ -2469,6 +2529,7 @@
else
#endif /* POLARSSL_KEY_EXCHANGE_RSA_ENABLED */
{
+ SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE );
}