Library update

Detail:
  This is release 2.16.5 direct from ARM, with customisations to ro_config.h/timing.c/entropy_poll.c/net_sockets.[c|h] to port to RISC OS.

Version 2.17. Tagged as 'mbedTLS-2_17'

VersionNum

-/* (2.16)
+/* (2.17)
  *
  * This file is automatically maintained by srccommit, do not edit manually.
  *
  */
-#define Module_MajorVersion_CMHG        2.16
+#define Module_MajorVersion_CMHG        2.17
 #define Module_MinorVersion_CMHG        
-#define Module_Date_CMHG                30 Jan 2020
+#define Module_Date_CMHG                24 Feb 2020
 
-#define Module_MajorVersion             "2.16"
-#define Module_Version                  216
+#define Module_MajorVersion             "2.17"
+#define Module_Version                  217
 #define Module_MinorVersion             ""
-#define Module_Date                     "30 Jan 2020"
+#define Module_Date                     "24 Feb 2020"
 
-#define Module_ApplicationDate          "30-Jan-20"
+#define Module_ApplicationDate          "24-Feb-20"
 
 #define Module_ComponentName            "mbedTLS"
 
-#define Module_FullVersion              "2.16"
-#define Module_HelpVersion              "2.16 (30 Jan 2020)"
-#define Module_LibraryVersionInfo       "2:16"
+#define Module_FullVersion              "2.17"
+#define Module_HelpVersion              "2.17 (24 Feb 2020)"
+#define Module_LibraryVersionInfo       "2:17"

c/bignum

@@ -157,9 +157,10 @@ int mbedtls_mpi_shrink( mbedtls_mpi *X, size_t nblimbs )
     if( nblimbs > MBEDTLS_MPI_MAX_LIMBS )
         return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
 
-    /* Actually resize up in this case */
+    /* Actually resize up if there are currently fewer than nblimbs limbs. */
     if( X->n <= nblimbs )
         return( mbedtls_mpi_grow( X, nblimbs ) );
+    /* After this point, then X->n > nblimbs and in particular X->n > 0. */
 
     for( i = X->n - 1; i > 0; i-- )
         if( X->p[i] != 0 )
@@ -198,7 +199,7 @@ int mbedtls_mpi_copy( mbedtls_mpi *X, const mbedtls_mpi *Y )
     if( X == Y )
         return( 0 );
 
-    if( Y->p == NULL )
+    if( Y->n == 0 )
     {
         mbedtls_mpi_free( X );
         return( 0 );

c/cipher

@@ -361,6 +361,10 @@ int mbedtls_cipher_update( mbedtls_cipher_context_t *ctx, const unsigned char *i
 
     *olen = 0;
     block_size = mbedtls_cipher_get_block_size( ctx );
+    if ( 0 == block_size )
+    {
+        return( MBEDTLS_ERR_CIPHER_INVALID_CONTEXT );
+    }
 
     if( ctx->cipher_info->mode == MBEDTLS_MODE_ECB )
     {
@@ -396,11 +400,6 @@ int mbedtls_cipher_update( mbedtls_cipher_context_t *ctx, const unsigned char *i
     }
 #endif
 
-    if ( 0 == block_size )
-    {
-        return( MBEDTLS_ERR_CIPHER_INVALID_CONTEXT );
-    }
-
     if( input == output &&
        ( ctx->unprocessed_len != 0 || ilen % block_size ) )
     {
@@ -459,11 +458,6 @@ int mbedtls_cipher_update( mbedtls_cipher_context_t *ctx, const unsigned char *i
          */
         if( 0 != ilen )
         {
-            if( 0 == block_size )
-            {
-                return( MBEDTLS_ERR_CIPHER_INVALID_CONTEXT );
-            }
-
             /* Encryption: only cache partial blocks
              * Decryption w/ padding: always keep at least one whole block
              * Decryption w/o padding: only cache partial blocks

c/ecdsa

@@ -297,7 +297,7 @@ static int ecdsa_sign_restartable( mbedtls_ecp_group *grp,
     *p_sign_tries = 0;
     do
     {
-        if( *p_sign_tries++ > 10 )
+        if( (*p_sign_tries)++ > 10 )
         {
             ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
             goto cleanup;
@@ -310,7 +310,7 @@ static int ecdsa_sign_restartable( mbedtls_ecp_group *grp,
         *p_key_tries = 0;
         do
         {
-            if( *p_key_tries++ > 10 )
+            if( (*p_key_tries)++ > 10 )
             {
                 ret = MBEDTLS_ERR_ECP_RANDOM_FAILED;
                 goto cleanup;

c/pkparse

@@ -677,6 +677,32 @@ int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
 }
 
 #if defined(MBEDTLS_RSA_C)
+/*
+ * Wrapper around mbedtls_asn1_get_mpi() that rejects zero.
+ *
+ * The value zero is:
+ * - never a valid value for an RSA parameter
+ * - interpreted as "omitted, please reconstruct" by mbedtls_rsa_complete().
+ *
+ * Since values can't be omitted in PKCS#1, passing a zero value to
+ * rsa_complete() would be incorrect, so reject zero values early.
+ */
+static int asn1_get_nonzero_mpi( unsigned char **p,
+                                 const unsigned char *end,
+                                 mbedtls_mpi *X )
+{
+    int ret;
+
+    ret = mbedtls_asn1_get_mpi( p, end, X );
+    if( ret != 0 )
+        return( ret );
+
+    if( mbedtls_mpi_cmp_int( X, 0 ) == 0 )
+        return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
+
+    return( 0 );
+}
+
 /*
  * Parse a PKCS#1 encoded private RSA key
  */
@@ -729,54 +755,84 @@ static int pk_parse_key_pkcs1_der( mbedtls_rsa_context *rsa,
     }
 
     /* Import N */
-    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
-                                      MBEDTLS_ASN1_INTEGER ) ) != 0 ||
-        ( ret = mbedtls_rsa_import_raw( rsa, p, len, NULL, 0, NULL, 0,
-                                        NULL, 0, NULL, 0 ) ) != 0 )
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_rsa_import( rsa, &T, NULL, NULL,
+                                        NULL, NULL ) ) != 0 )
         goto cleanup;
-    p += len;
 
     /* Import E */
-    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
-                                      MBEDTLS_ASN1_INTEGER ) ) != 0 ||
-        ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, NULL, 0, NULL, 0,
-                                        NULL, 0, p, len ) ) != 0 )
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_rsa_import( rsa, NULL, NULL, NULL,
+                                        NULL, &T ) ) != 0 )
         goto cleanup;
-    p += len;
 
     /* Import D */
-    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
-                                      MBEDTLS_ASN1_INTEGER ) ) != 0 ||
-        ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, NULL, 0, NULL, 0,
-                                        p, len, NULL, 0 ) ) != 0 )
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_rsa_import( rsa, NULL, NULL, NULL,
+                                        &T, NULL ) ) != 0 )
         goto cleanup;
-    p += len;
 
     /* Import P */
-    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
-                                      MBEDTLS_ASN1_INTEGER ) ) != 0 ||
-        ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, p, len, NULL, 0,
-                                        NULL, 0, NULL, 0 ) ) != 0 )
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_rsa_import( rsa, NULL, &T, NULL,
+                                        NULL, NULL ) ) != 0 )
         goto cleanup;
-    p += len;
 
     /* Import Q */
-    if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
-                                      MBEDTLS_ASN1_INTEGER ) ) != 0 ||
-        ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, NULL, 0, p, len,
-                                        NULL, 0, NULL, 0 ) ) != 0 )
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_rsa_import( rsa, NULL, NULL, &T,
+                                        NULL, NULL ) ) != 0 )
         goto cleanup;
-    p += len;
 
-    /* Complete the RSA private key */
-    if( ( ret = mbedtls_rsa_complete( rsa ) ) != 0 )
-        goto cleanup;
+#if !defined(MBEDTLS_RSA_NO_CRT) && !defined(MBEDTLS_RSA_ALT)
+    /*
+    * The RSA CRT parameters DP, DQ and QP are nominally redundant, in
+    * that they can be easily recomputed from D, P and Q. However by
+    * parsing them from the PKCS1 structure it is possible to avoid
+    * recalculating them which both reduces the overhead of loading
+    * RSA private keys into memory and also avoids side channels which
+    * can arise when computing those values, since all of D, P, and Q
+    * are secret. See https://eprint.iacr.org/2020/055 for a
+    * description of one such attack.
+    */
+
+    /* Import DP */
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_mpi_copy( &rsa->DP, &T ) ) != 0 )
+       goto cleanup;
+
+    /* Import DQ */
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_mpi_copy( &rsa->DQ, &T ) ) != 0 )
+       goto cleanup;
+
+    /* Import QP */
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = mbedtls_mpi_copy( &rsa->QP, &T ) ) != 0 )
+       goto cleanup;
+
+#else
+    /* Verify existance of the CRT params */
+    if( ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 ||
+        ( ret = asn1_get_nonzero_mpi( &p, end, &T ) ) != 0 )
+       goto cleanup;
+#endif
 
-    /* Check optional parameters */
-    if( ( ret = mbedtls_asn1_get_mpi( &p, end, &T ) ) != 0 ||
-        ( ret = mbedtls_asn1_get_mpi( &p, end, &T ) ) != 0 ||
-        ( ret = mbedtls_asn1_get_mpi( &p, end, &T ) ) != 0 )
+    /* rsa_complete() doesn't complete anything with the default
+     * implementation but is still called:
+     * - for the benefit of alternative implementation that may want to
+     *   pre-compute stuff beyond what's provided (eg Montgomery factors)
+     * - as is also sanity-checks the key
+     *
+     * Furthermore, we also check the public part for consistency with
+     * mbedtls_pk_parse_pubkey(), as it includes size minima for example.
+     */
+    if( ( ret = mbedtls_rsa_complete( rsa ) ) != 0 ||
+        ( ret = mbedtls_rsa_check_pubkey( rsa ) ) != 0 )
+    {
         goto cleanup;
+    }
 
     if( p != end )
     {

c/rsa

@@ -249,6 +249,9 @@ int mbedtls_rsa_complete( mbedtls_rsa_context *ctx )
 {
     int ret = 0;
     int have_N, have_P, have_Q, have_D, have_E;
+#if !defined(MBEDTLS_RSA_NO_CRT)
+    int have_DP, have_DQ, have_QP;
+#endif
     int n_missing, pq_missing, d_missing, is_pub, is_priv;
 
     RSA_VALIDATE_RET( ctx != NULL );
@@ -259,6 +262,12 @@ int mbedtls_rsa_complete( mbedtls_rsa_context *ctx )
     have_D = ( mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 );
     have_E = ( mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0 );
 
+#if !defined(MBEDTLS_RSA_NO_CRT)
+    have_DP = ( mbedtls_mpi_cmp_int( &ctx->DP, 0 ) != 0 );
+    have_DQ = ( mbedtls_mpi_cmp_int( &ctx->DQ, 0 ) != 0 );
+    have_QP = ( mbedtls_mpi_cmp_int( &ctx->QP, 0 ) != 0 );
+#endif
+
     /*
      * Check whether provided parameters are enough
      * to deduce all others. The following incomplete
@@ -324,7 +333,7 @@ int mbedtls_rsa_complete( mbedtls_rsa_context *ctx )
      */
 
 #if !defined(MBEDTLS_RSA_NO_CRT)
-    if( is_priv )
+    if( is_priv && ! ( have_DP && have_DQ && have_QP ) )
     {
         ret = mbedtls_rsa_deduce_crt( &ctx->P,  &ctx->Q,  &ctx->D,
                                       &ctx->DP, &ctx->DQ, &ctx->QP );

c/x509write_csr

@@ -226,7 +226,9 @@ int mbedtls_x509write_csr_der( mbedtls_x509write_csr *ctx, unsigned char *buf, s
     /*
      * Prepare signature
      */
-    mbedtls_md( mbedtls_md_info_from_type( ctx->md_alg ), c, len, hash );
+    ret = mbedtls_md( mbedtls_md_info_from_type( ctx->md_alg ), c, len, hash );
+    if( ret != 0 )
+        return( ret );
 
     if( ( ret = mbedtls_pk_sign( ctx->key, ctx->md_alg, hash, 0, sig, &sig_len,
                                  f_rng, p_rng ) ) != 0 )

mbedtls/h/version

@@ -40,16 +40,16 @@
  */
 #define MBEDTLS_VERSION_MAJOR  2
 #define MBEDTLS_VERSION_MINOR  16
-#define MBEDTLS_VERSION_PATCH  4
+#define MBEDTLS_VERSION_PATCH  5
 
 /**
  * The single version number has the following structure:
  *    MMNNPP00
  *    Major version | Minor version | Patch version
  */
-#define MBEDTLS_VERSION_NUMBER         0x02100400
-#define MBEDTLS_VERSION_STRING         "2.16.4"
-#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 2.16.4"
+#define MBEDTLS_VERSION_NUMBER         0x02100500
+#define MBEDTLS_VERSION_STRING         "2.16.5"
+#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 2.16.5"
 
 #if defined(MBEDTLS_VERSION_C)