Adapt cipher and MD layer with _init() and _free()

include/polarssl/cipher.h

@@ -331,10 +331,26 @@ const cipher_info_t *cipher_info_from_values( const cipher_id_t cipher_id,
                                               int key_length,
                                               const cipher_mode_t mode );
 
+/**
+ * \brief               Initialize a cipher_context (as NONE)
+ */
+void cipher_init( cipher_context_t *ctx );
+
+/**
+ * \brief               Free and clear the cipher-specific context of ctx.
+ *                      Freeing ctx itself remains the responsibility of the
+ *                      caller.
+ */
+void cipher_free( cipher_context_t *ctx );
+
 /**
  * \brief               Initialises and fills the cipher context structure with
  *                      the appropriate values.
  *
+ * \note                Currently also clears structure. In future versions you
+ *                      will be required to call cipher_init() on the structure
+ *                      first.
+ *
  * \param ctx           context to initialise. May not be NULL.
  * \param cipher_info   cipher to use.
  *
@@ -349,10 +365,11 @@ int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info );
  * \brief               Free the cipher-specific context of ctx. Freeing ctx
  *                      itself remains the responsibility of the caller.
  *
+ * \note                Deprecated: Redirects to cipher_free()
+ *
  * \param ctx           Free the cipher-specific context
  *
- * \returns             0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if
- *                      parameter verification fails.
+ * \returns             0
  */
 int cipher_free_ctx( cipher_context_t *ctx );
 

include/polarssl/md.h

@@ -172,10 +172,26 @@ const md_info_t *md_info_from_string( const char *md_name );
  */
 const md_info_t *md_info_from_type( md_type_t md_type );
 
+/**
+ * \brief               Initialize a md_context (as NONE)
+ */
+void md_init( md_context_t *ctx );
+
+/**
+ * \brief               Free and clear the message-specific context of ctx.
+ *                      Freeing ctx itself remains the responsibility of the
+ *                      caller.
+ */
+void md_free( md_context_t *ctx );
+
 /**
  * \brief          Initialises and fills the message digest context structure
  *                 with the appropriate values.
  *
+ * \note           Currently also clears structure. In future versions you
+ *                 will be required to call md_init() on the structure
+ *                 first.
+ *
  * \param ctx      context to initialise. May not be NULL. The
  *                 digest-specific context (ctx->md_ctx) must be NULL. It will
  *                 be allocated, and must be freed using md_free_ctx() later.
@@ -191,10 +207,11 @@ int md_init_ctx( md_context_t *ctx, const md_info_t *md_info );
  * \brief          Free the message-specific context of ctx. Freeing ctx itself
  *                 remains the responsibility of the caller.
  *
+ * \note           Deprecated: Redirects to md_free()
+ *
  * \param ctx      Free the message-specific context
  *
- * \returns        0 on success, POLARSSL_ERR_MD_BAD_INPUT_DATA if parameter
- *                 verification fails.
+ * \returns        0
  */
 int md_free_ctx( md_context_t *ctx );
 

library/ccm.c

@@ -61,6 +61,8 @@ int ccm_init( ccm_context *ctx, cipher_id_t cipher,
 
     memset( ctx, 0, sizeof( ccm_context ) );
 
+    cipher_init( &ctx->cipher_ctx );
+
     cipher_info = cipher_info_from_values( cipher, keysize, POLARSSL_MODE_ECB );
     if( cipher_info == NULL )
         return( POLARSSL_ERR_CCM_BAD_INPUT );
@@ -85,7 +87,7 @@ int ccm_init( ccm_context *ctx, cipher_id_t cipher,
  */
 void ccm_free( ccm_context *ctx )
 {
-    (void) cipher_free_ctx( &ctx->cipher_ctx );
+    cipher_free( &ctx->cipher_ctx );
     polarssl_zeroize( ctx, sizeof( ccm_context ) );
 }
 

library/cipher.c

@@ -125,6 +125,22 @@ const cipher_info_t *cipher_info_from_values( const cipher_id_t cipher_id,
     return( NULL );
 }
 
+void cipher_init( cipher_context_t *ctx )
+{
+    memset( ctx, 0, sizeof( cipher_context_t ) );
+}
+
+void cipher_free( cipher_context_t *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    if( ctx->cipher_ctx )
+        ctx->cipher_info->base->ctx_free_func( ctx->cipher_ctx );
+
+    polarssl_zeroize( ctx, sizeof(cipher_context_t) );
+}
+
 int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info )
 {
     if( NULL == cipher_info || NULL == ctx )
@@ -151,13 +167,10 @@ int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info )
     return( 0 );
 }
 
+/* Deprecated, redirects to cipher_free() */
 int cipher_free_ctx( cipher_context_t *ctx )
 {
-    if( ctx == NULL || ctx->cipher_info == NULL )
-        return( POLARSSL_ERR_CIPHER_BAD_INPUT_DATA );
-
-    ctx->cipher_info->base->ctx_free_func( ctx->cipher_ctx );
-    polarssl_zeroize( ctx, sizeof(cipher_context_t) );
+    cipher_free( ctx );
 
     return( 0 );
 }

library/gcm.c

@@ -157,6 +157,8 @@ int gcm_init( gcm_context *ctx, cipher_id_t cipher, const unsigned char *key,
 
     memset( ctx, 0, sizeof(gcm_context) );
 
+    cipher_init( &ctx->cipher_ctx );
+
     cipher_info = cipher_info_from_values( cipher, keysize, POLARSSL_MODE_ECB );
     if( cipher_info == NULL )
         return( POLARSSL_ERR_GCM_BAD_INPUT );
@@ -493,7 +495,7 @@ int gcm_auth_decrypt( gcm_context *ctx,
 
 void gcm_free( gcm_context *ctx )
 {
-    (void) cipher_free_ctx( &ctx->cipher_ctx );
+    cipher_free( &ctx->cipher_ctx );
     polarssl_zeroize( ctx, sizeof( gcm_context ) );
 }
 

library/hmac_drbg.c

@@ -93,6 +93,8 @@ int hmac_drbg_init_buf( hmac_drbg_context *ctx,
 
     memset( ctx, 0, sizeof( hmac_drbg_context ) );
 
+    md_init( &ctx->md_ctx );
+
     if( ( ret = md_init_ctx( &ctx->md_ctx, md_info ) ) != 0 )
         return( ret );
 
@@ -165,6 +167,8 @@ int hmac_drbg_init( hmac_drbg_context *ctx,
 
     memset( ctx, 0, sizeof( hmac_drbg_context ) );
 
+    md_init( &ctx->md_ctx );
+
     if( ( ret = md_init_ctx( &ctx->md_ctx, md_info ) ) != 0 )
         return( ret );
 

library/md.c

@@ -172,6 +172,22 @@ const md_info_t *md_info_from_type( md_type_t md_type )
     }
 }
 
+void md_init( md_context_t *ctx )
+{
+    memset( ctx, 0, sizeof( md_context_t ) );
+}
+
+void md_free( md_context_t *ctx )
+{
+    if( ctx == NULL )
+        return;
+
+    if( ctx->md_ctx )
+        ctx->md_info->ctx_free_func( ctx->md_ctx );
+
+    polarssl_zeroize( ctx, sizeof( md_context_t ) );
+}
+
 int md_init_ctx( md_context_t *ctx, const md_info_t *md_info )
 {
     if( md_info == NULL || ctx == NULL )
@@ -191,12 +207,7 @@ int md_init_ctx( md_context_t *ctx, const md_info_t *md_info )
 
 int md_free_ctx( md_context_t *ctx )
 {
-    if( ctx == NULL || ctx->md_info == NULL )
-        return( POLARSSL_ERR_MD_BAD_INPUT_DATA );
-
-    ctx->md_info->ctx_free_func( ctx->md_ctx );
-
-    polarssl_zeroize( ctx, sizeof( md_context_t ) );
+    md_free( ctx );
 
     return( 0 );
 }

library/pkcs12.c

@@ -194,6 +194,8 @@ int pkcs12_pbe( asn1_buf *pbe_params, int mode,
         return( ret );
     }
 
+    cipher_init( &cipher_ctx );
+
     if( ( ret = cipher_init_ctx( &cipher_ctx, cipher_info ) ) != 0 )
         goto exit;
 
@@ -218,7 +220,7 @@ int pkcs12_pbe( asn1_buf *pbe_params, int mode,
 exit:
     polarssl_zeroize( key, sizeof( key ) );
     polarssl_zeroize( iv,  sizeof( iv  ) );
-    cipher_free_ctx( &cipher_ctx );
+    cipher_free( &cipher_ctx );
 
     return( ret );
 }
@@ -265,6 +267,8 @@ int pkcs12_derivation( unsigned char *data, size_t datalen,
     if( md_info == NULL )
         return( POLARSSL_ERR_PKCS12_FEATURE_UNAVAILABLE );
 
+    md_init( &md_ctx );
+
     if( ( ret = md_init_ctx( &md_ctx, md_info ) ) != 0 )
         return( ret );
     hlen = md_get_size( md_info );
@@ -348,7 +352,7 @@ exit:
     polarssl_zeroize( hash_block, sizeof( hash_block ) );
     polarssl_zeroize( hash_output, sizeof( hash_output ) );
 
-    md_free_ctx( &md_ctx );
+    md_free( &md_ctx );
 
     return( ret );
 }

library/pkcs5.c

@@ -130,9 +130,6 @@ int pkcs5_pbes2( asn1_buf *pbe_params, int mode,
     p = pbe_params->p;
     end = p + pbe_params->len;
 
-    memset( &md_ctx, 0, sizeof(md_context_t) );
-    memset( &cipher_ctx, 0, sizeof(cipher_context_t) );
-
     /*
      *  PBES2-params ::= SEQUENCE {
      *    keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
@@ -187,6 +184,9 @@ int pkcs5_pbes2( asn1_buf *pbe_params, int mode,
         return( POLARSSL_ERR_PKCS5_INVALID_FORMAT );
     }
 
+    md_init( &md_ctx );
+    cipher_init( &cipher_ctx );
+
     memcpy( iv, enc_scheme_params.p, enc_scheme_params.len );
 
     if( ( ret = md_init_ctx( &md_ctx, md_info ) ) != 0 )
@@ -209,8 +209,8 @@ int pkcs5_pbes2( asn1_buf *pbe_params, int mode,
         ret = POLARSSL_ERR_PKCS5_PASSWORD_MISMATCH;
 
 exit:
-    md_free_ctx( &md_ctx );
-    cipher_free_ctx( &cipher_ctx );
+    md_free( &md_ctx );
+    cipher_free( &cipher_ctx );
 
     return( ret );
 }
@@ -364,12 +364,20 @@ int pkcs5_self_test( int verbose )
     int ret, i;
     unsigned char key[64];
 
+    md_init( &sha1_ctx );
+
     info_sha1 = md_info_from_type( POLARSSL_MD_SHA1 );
     if( info_sha1 == NULL )
-        return( 1 );
+    {
+        ret = 1;
+        goto exit;
+    }
 
     if( ( ret = md_init_ctx( &sha1_ctx, info_sha1 ) ) != 0 )
-        return( 1 );
+    {
+        ret = 1;
+        goto exit;
+    }
 
     if( verbose != 0 )
         polarssl_printf( "  PBKDF2 note: test #3 may be slow!\n" );
@@ -387,7 +395,8 @@ int pkcs5_self_test( int verbose )
             if( verbose != 0 )
                 polarssl_printf( "failed\n" );
 
-            return( 1 );
+            ret = 1;
+            goto exit;
         }
 
         if( verbose != 0 )
@@ -396,8 +405,8 @@ int pkcs5_self_test( int verbose )
 
     polarssl_printf( "\n" );
 
-    if( ( ret = md_free_ctx( &sha1_ctx ) ) != 0 )
-        return( 1 );
+exit:
+    md_free( &sha1_ctx );
 
     return( 0 );
 }

library/rsa.c

@@ -540,6 +540,7 @@ int rsa_rsaes_oaep_encrypt( rsa_context *ctx,
     *p++ = 1;
     memcpy( p, input, ilen );
 
+    md_init( &md_ctx );
     md_init_ctx( &md_ctx, md_info );
 
     // maskedDB: Apply dbMask to DB
@@ -552,7 +553,7 @@ int rsa_rsaes_oaep_encrypt( rsa_context *ctx,
     mgf_mask( output + 1, hlen, output + hlen + 1, olen - hlen - 1,
                &md_ctx );
 
-    md_free_ctx( &md_ctx );
+    md_free( &md_ctx );
 
     return( ( mode == RSA_PUBLIC )
             ? rsa_public(  ctx, output, output )
@@ -708,6 +709,7 @@ int rsa_rsaes_oaep_decrypt( rsa_context *ctx,
      */
     hlen = md_get_size( md_info );
 
+    md_init( &md_ctx );
     md_init_ctx( &md_ctx, md_info );
 
     /* Generate lHash */
@@ -721,7 +723,7 @@ int rsa_rsaes_oaep_decrypt( rsa_context *ctx,
     mgf_mask( buf + hlen + 1, ilen - hlen - 1, buf + 1, hlen,
                &md_ctx );
 
-    md_free_ctx( &md_ctx );
+    md_free( &md_ctx );
 
     /*
      * Check contents, in "constant-time"
@@ -951,6 +953,7 @@ int rsa_rsassa_pss_sign( rsa_context *ctx,
     memcpy( p, salt, slen );
     p += slen;
 
+    md_init( &md_ctx );
     md_init_ctx( &md_ctx, md_info );
 
     // Generate H = Hash( M' )
@@ -970,7 +973,7 @@ int rsa_rsassa_pss_sign( rsa_context *ctx,
     //
     mgf_mask( sig + offset, olen - hlen - 1 - offset, p, hlen, &md_ctx );
 
-    md_free_ctx( &md_ctx );
+    md_free( &md_ctx );
 
     msb = mpi_msb( &ctx->N ) - 1;
     sig[0] &= 0xFF >> ( olen * 8 - msb );
@@ -1182,6 +1185,7 @@ int rsa_rsassa_pss_verify_ext( rsa_context *ctx,
     if( buf[0] >> ( 8 - siglen * 8 + msb ) )
         return( POLARSSL_ERR_RSA_BAD_INPUT_DATA );
 
+    md_init( &md_ctx );
     md_init_ctx( &md_ctx, md_info );
 
     mgf_mask( p, siglen - hlen - 1, p + siglen - hlen - 1, hlen, &md_ctx );
@@ -1194,7 +1198,7 @@ int rsa_rsassa_pss_verify_ext( rsa_context *ctx,
     if( p == buf + siglen ||
         *p++ != 0x01 )
     {
-        md_free_ctx( &md_ctx );
+        md_free( &md_ctx );
         return( POLARSSL_ERR_RSA_INVALID_PADDING );
     }
 
@@ -1204,7 +1208,7 @@ int rsa_rsassa_pss_verify_ext( rsa_context *ctx,
     if( expected_salt_len != RSA_SALT_LEN_ANY &&
         slen != (size_t) expected_salt_len )
     {
-        md_free_ctx( &md_ctx );
+        md_free( &md_ctx );
         return( POLARSSL_ERR_RSA_INVALID_PADDING );
     }
 
@@ -1216,7 +1220,7 @@ int rsa_rsassa_pss_verify_ext( rsa_context *ctx,
     md_update( &md_ctx, p, slen );
     md_finish( &md_ctx, result );
 
-    md_free_ctx( &md_ctx );
+    md_free( &md_ctx );
 
     if( memcmp( p + slen, result, hlen ) == 0 )
         return( 0 );

library/ssl_cli.c

@@ -1758,6 +1758,8 @@ static int ssl_parse_server_key_exchange( ssl_context *ssl )
         {
             md_context_t ctx;
 
+            md_init( &ctx );
+
             /* Info from md_alg will be used instead */
             hashlen = 0;
 
@@ -1779,7 +1781,7 @@ static int ssl_parse_server_key_exchange( ssl_context *ssl )
             md_update( &ctx, ssl->handshake->randbytes, 64 );
             md_update( &ctx, ssl->in_msg + 4, params_len );
             md_finish( &ctx, hash );
-            md_free_ctx( &ctx );
+            md_free( &ctx );
         }
         else
 #endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 || \

library/ssl_srv.c

@@ -2380,6 +2380,8 @@ curve_matching_done:
             md_context_t ctx;
             const md_info_t *md_info = md_info_from_type( md_alg );
 
+            md_init( &ctx );
+
             /* Info from md_alg will be used instead */
             hashlen = 0;
 
@@ -2400,13 +2402,7 @@ curve_matching_done:
             md_update( &ctx, ssl->handshake->randbytes, 64 );
             md_update( &ctx, dig_signed, dig_signed_len );
             md_finish( &ctx, hash );
-
-            if( ( ret = md_free_ctx( &ctx ) ) != 0 )
-            {
-                SSL_DEBUG_RET( 1, "md_free_ctx", ret );
-                return( ret );
-            }
-
+            md_free( &ctx );
         }
         else
 #endif /* POLARSSL_SSL_PROTO_TLS1 || POLARSSL_SSL_PROTO_TLS1_1 || \

library/ssl_tls.c

@@ -3311,6 +3311,12 @@ static void ssl_handshake_params_init( ssl_handshake_params *handshake,
 static void ssl_transform_init( ssl_transform *transform )
 {
     memset( transform, 0, sizeof(ssl_transform) );
+
+    cipher_init( &transform->cipher_ctx_enc );
+    cipher_init( &transform->cipher_ctx_dec );
+
+    md_init( &transform->md_ctx_enc );
+    md_init( &transform->md_ctx_dec );
 }
 
 void ssl_session_init( ssl_session *session )
@@ -4506,11 +4512,11 @@ void ssl_transform_free( ssl_transform *transform )
     inflateEnd( &transform->ctx_inflate );
 #endif
 
-    cipher_free_ctx( &transform->cipher_ctx_enc );
-    cipher_free_ctx( &transform->cipher_ctx_dec );
+    cipher_free( &transform->cipher_ctx_enc );
+    cipher_free( &transform->cipher_ctx_dec );
 
-    md_free_ctx( &transform->md_ctx_enc );
-    md_free_ctx( &transform->md_ctx_dec );
+    md_free( &transform->md_ctx_enc );
+    md_free( &transform->md_ctx_dec );
 
     polarssl_zeroize( transform, sizeof( ssl_transform ) );
 }