Merge remote-tracking branch 'public/pr/1811' into mbedtls-2.1
diff --git a/ChangeLog b/ChangeLog
index 8db46ee..64dce14 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,8 +3,26 @@
 = mbed TLS x.x.x branch released xxxx-xx-xx
 
 Bugfix
-   * Fixes an issue with MBEDTLS_CHACHAPOLY_C which would not compile if
-     MBEDTLS_ARC4_C and MBEDTLS_CIPHER_NULL_CIPHER weren't also defined. #1890
+    * Fix failure in hmac_drbg in the benchmark sample application, when
+      MBEDTLS_THREADING_C is defined. Found by TrinityTonic, #1095
+    * Fix a bug in the update function for SSL ticket keys which previously
+      invalidated keys of a lifetime of less than a 1s. Fixes #1968.
+
+Changes
+   * Add tests for session resumption in DTLS.
+
+= mbed TLS 2.1.15 branch released 2018-08-31
+
+Security
+   * Fix an issue in the X.509 module which could lead to a buffer overread
+     during certificate extensions parsing. In case of receiving malformed
+     input (extensions length field equal to 0), an illegal read of one byte
+     beyond the input buffer is made. Found and analyzed by Nathan Crandall.
+
+Bugfix
+   * Fix a potential memory leak in mbedtls_ssl_setup() function. An allocation
+     failure in the function could lead to other buffers being leaked.
+   * Fixes a missing test dependency on MBEDTLS_ARC4_C. #1890
    * Fix a memory leak in ecp_mul_comb() if ecp_precompute_comb() fails.
      Fix contributed by Espressif Systems.
    * Add ecc extensions only if an ecc based ciphersuite is used.
@@ -12,6 +30,18 @@
      interoperability issues with BouncyCastle. Raised by milenamil in #1157.
    * Fix potential use-after-free in mbedtls_ssl_get_max_frag_len()
      and mbedtls_ssl_get_record_expansion() after a session reset. Fixes #1941.
+   * Fix a miscalculation of the maximum record expansion in
+     mbedtls_ssl_get_record_expansion() in case of CBC ciphersuites
+     in (D)TLS versions 1.1 or higher. Fixes #1914.
+   * Fix a bug that caused SSL/TLS clients to incorrectly abort the handshake
+     with TLS versions 1.1 and earlier when the server requested authentication
+     without providing a list of CAs. This was due to an overly strict bounds
+     check in parsing the CertificateRequest message, introduced in
+     Mbed TLS 2.12.0. Fixes #1954.
+   * Fix undefined shifts with negative values in certificates parsing
+     (found by Catena cyber using oss-fuzz)
+   * Fix memory leak and free without initialization in pk_encrypt
+     and pk_decrypt example programs. Reported by Brace Stout. Fixes #1128.
 
 = mbed TLS 2.1.14 branch released 2018-07-25
 
diff --git a/doxygen/input/doc_mainpage.h b/doxygen/input/doc_mainpage.h
index 4e5c754..a44f02d 100644
--- a/doxygen/input/doc_mainpage.h
+++ b/doxygen/input/doc_mainpage.h
@@ -21,7 +21,7 @@
  */
 
 /**
- * @mainpage mbed TLS v2.1.14 source code documentation
+ * @mainpage mbed TLS v2.1.15 source code documentation
  *
  * This documentation describes the internal structure of mbed TLS.  It was
  * automatically generated from specially formatted comment blocks in
diff --git a/doxygen/mbedtls.doxyfile b/doxygen/mbedtls.doxyfile
index 57bc518..89a10c2 100644
--- a/doxygen/mbedtls.doxyfile
+++ b/doxygen/mbedtls.doxyfile
@@ -28,7 +28,7 @@
 # identify the project. Note that if you do not use Doxywizard you need
 # to put quotes around the project name if it contains spaces.
 
-PROJECT_NAME           = "mbed TLS v2.1.14"
+PROJECT_NAME           = "mbed TLS v2.1.15"
 
 # The PROJECT_NUMBER tag can be used to enter a project or revision number.
 # This could be handy for archiving the generated documentation or
diff --git a/include/mbedtls/version.h b/include/mbedtls/version.h
index 9ba56bc..7d78ac4 100644
--- a/include/mbedtls/version.h
+++ b/include/mbedtls/version.h
@@ -39,16 +39,16 @@
  */
 #define MBEDTLS_VERSION_MAJOR  2
 #define MBEDTLS_VERSION_MINOR  1
-#define MBEDTLS_VERSION_PATCH  14
+#define MBEDTLS_VERSION_PATCH  15
 
 /**
  * The single version number has the following structure:
  *    MMNNPP00
  *    Major version | Minor version | Patch version
  */
-#define MBEDTLS_VERSION_NUMBER         0x02010E00
-#define MBEDTLS_VERSION_STRING         "2.1.14"
-#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 2.1.14"
+#define MBEDTLS_VERSION_NUMBER         0x02010F00
+#define MBEDTLS_VERSION_STRING         "2.1.15"
+#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 2.1.15"
 
 #if defined(MBEDTLS_VERSION_C)
 
diff --git a/library/CMakeLists.txt b/library/CMakeLists.txt
index 994d4bc..e5a9546 100644
--- a/library/CMakeLists.txt
+++ b/library/CMakeLists.txt
@@ -138,15 +138,15 @@
 
 if(USE_SHARED_MBEDTLS_LIBRARY)
     add_library(mbedcrypto SHARED ${src_crypto})
-    set_target_properties(mbedcrypto PROPERTIES VERSION 2.1.14 SOVERSION 0)
+    set_target_properties(mbedcrypto PROPERTIES VERSION 2.1.15 SOVERSION 0)
     target_link_libraries(mbedcrypto ${libs})
 
     add_library(mbedx509 SHARED ${src_x509})
-    set_target_properties(mbedx509 PROPERTIES VERSION 2.1.14 SOVERSION 0)
+    set_target_properties(mbedx509 PROPERTIES VERSION 2.1.15 SOVERSION 0)
     target_link_libraries(mbedx509 ${libs} mbedcrypto)
 
     add_library(mbedtls SHARED ${src_tls})
-    set_target_properties(mbedtls PROPERTIES VERSION 2.1.14 SOVERSION 10)
+    set_target_properties(mbedtls PROPERTIES VERSION 2.1.15 SOVERSION 10)
     target_link_libraries(mbedtls ${libs} mbedx509)
 
     install(TARGETS mbedtls mbedx509 mbedcrypto
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 916a29c..8e5c02b 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -2504,7 +2504,7 @@
      * therefore the buffer length at this point must be greater than that
      * regardless of the actual code path.
      */
-    if( ssl->in_hslen <= mbedtls_ssl_hs_hdr_len( ssl ) + 3 + n )
+    if( ssl->in_hslen <= mbedtls_ssl_hs_hdr_len( ssl ) + 2 + n )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad certificate request message" ) );
         return( MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST );
@@ -3098,8 +3098,8 @@
 
     msg = ssl->in_msg + mbedtls_ssl_hs_hdr_len( ssl );
 
-    lifetime = ( msg[0] << 24 ) | ( msg[1] << 16 ) |
-               ( msg[2] <<  8 ) | ( msg[3]       );
+    lifetime = ( ((uint32_t) msg[0]) << 24 ) | ( msg[1] << 16 ) |
+               ( msg[2] << 8 ) | ( msg[3] );
 
     ticket_len = ( msg[4] << 8 ) | ( msg[5] );
 
diff --git a/library/ssl_ticket.c b/library/ssl_ticket.c
index 0e27900..a27d2ec 100644
--- a/library/ssl_ticket.c
+++ b/library/ssl_ticket.c
@@ -101,7 +101,7 @@
         uint32_t current_time = (uint32_t) time( NULL );
         uint32_t key_time = ctx->keys[ctx->active].generation_time;
 
-        if( current_time > key_time &&
+        if( current_time >= key_time &&
             current_time - key_time < ctx->ticket_lifetime )
         {
             return( 0 );
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 3ab482f..8091795 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1561,6 +1561,8 @@
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
         if( auth_done == 0 )
         {
+            unsigned char mac[MBEDTLS_SSL_MAC_ADD];
+
             /*
              * MAC(MAC_write_key, seq_num +
              *     TLSCipherText.type +
@@ -1583,10 +1585,12 @@
             mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc, pseudo_hdr, 13 );
             mbedtls_md_hmac_update( &ssl->transform_out->md_ctx_enc,
                              ssl->out_iv, ssl->out_msglen );
-            mbedtls_md_hmac_finish( &ssl->transform_out->md_ctx_enc,
-                             ssl->out_iv + ssl->out_msglen );
+            mbedtls_md_hmac_finish( &ssl->transform_out->md_ctx_enc, mac );
             mbedtls_md_hmac_reset( &ssl->transform_out->md_ctx_enc );
 
+            memcpy( ssl->out_iv + ssl->out_msglen, mac,
+                    ssl->transform_out->maclen );
+
             ssl->out_msglen += ssl->transform_out->maclen;
             auth_done++;
         }
@@ -5634,13 +5638,14 @@
     /*
      * Prepare base structures
      */
+    ssl->in_buf = NULL;
+    ssl->out_buf = NULL;
     if( ( ssl-> in_buf = mbedtls_calloc( 1, len ) ) == NULL ||
         ( ssl->out_buf = mbedtls_calloc( 1, len ) ) == NULL )
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "alloc(%d bytes) failed", len ) );
-        mbedtls_free( ssl->in_buf );
-        ssl->in_buf = NULL;
-        return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
+        ret = MBEDTLS_ERR_SSL_ALLOC_FAILED;
+        goto error;
     }
 
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
@@ -5675,9 +5680,32 @@
     }
 
     if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
-        return( ret );
+        goto error;
 
     return( 0 );
+
+error:
+    mbedtls_free( ssl->in_buf );
+    mbedtls_free( ssl->out_buf );
+
+    ssl->conf = NULL;
+
+    ssl->in_buf = NULL;
+    ssl->out_buf = NULL;
+
+    ssl->in_hdr = NULL;
+    ssl->in_ctr = NULL;
+    ssl->in_len = NULL;
+    ssl->in_iv = NULL;
+    ssl->in_msg = NULL;
+
+    ssl->out_hdr = NULL;
+    ssl->out_ctr = NULL;
+    ssl->out_len = NULL;
+    ssl->out_iv = NULL;
+    ssl->out_msg = NULL;
+
+    return( ret );
 }
 
 /*
@@ -6451,8 +6479,9 @@
 
 int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl )
 {
-    size_t transform_expansion;
+    size_t transform_expansion = 0;
     const mbedtls_ssl_transform *transform = ssl->transform_out;
+    unsigned block_size;
 
     if( transform == NULL )
         return( (int) mbedtls_ssl_hdr_len( ssl ) );
@@ -6471,8 +6500,25 @@
             break;
 
         case MBEDTLS_MODE_CBC:
-            transform_expansion = transform->maclen
-                      + mbedtls_cipher_get_block_size( &transform->cipher_ctx_enc );
+
+            block_size = mbedtls_cipher_get_block_size(
+                &transform->cipher_ctx_enc );
+
+            /* Expansion due to the addition of the MAC. */
+            transform_expansion += transform->maclen;
+
+            /* Expansion due to the addition of CBC padding;
+             * Theoretically up to 256 bytes, but we never use
+             * more than the block size of the underlying cipher. */
+            transform_expansion += block_size;
+
+            /* For TLS 1.1 or higher, an explicit IV is added
+             * after the record header. */
+#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
+            if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
+                transform_expansion += block_size;
+#endif /* MBEDTLS_SSL_PROTO_TLS1_1 || MBEDTLS_SSL_PROTO_TLS1_2 */
+
             break;
 
         default:
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 3d0765a..86fba64 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -152,6 +152,9 @@
 static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
                                       mbedtls_md_type_t md_alg )
 {
+    if( md_alg == MBEDTLS_MD_NONE )
+        return( -1 );
+
     if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
         return( 0 );
 
@@ -165,6 +168,9 @@
 static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
                                       mbedtls_pk_type_t pk_alg )
 {
+    if( pk_alg == MBEDTLS_PK_NONE )
+        return( -1 );
+
     if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
         return( 0 );
 
@@ -196,6 +202,9 @@
     {
         mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
 
+        if( gid == MBEDTLS_ECP_DP_NONE )
+            return( -1 );
+
         if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
             return( 0 );
 
@@ -558,18 +567,14 @@
         end_ext_data = *p + len;
 
         /* Get extension ID */
-        extn_oid.tag = **p;
-
-        if( ( ret = mbedtls_asn1_get_tag( p, end, &extn_oid.len, MBEDTLS_ASN1_OID ) ) != 0 )
+        if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &extn_oid.len,
+                                          MBEDTLS_ASN1_OID ) ) != 0 )
             return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
 
+        extn_oid.tag = MBEDTLS_ASN1_OID;
         extn_oid.p = *p;
         *p += extn_oid.len;
 
-        if( ( end - *p ) < 1 )
-            return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
-                    MBEDTLS_ERR_ASN1_OUT_OF_DATA );
-
         /* Get optional critical */
         if( ( ret = mbedtls_asn1_get_bool( p, end_ext_data, &is_critical ) ) != 0 &&
             ( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
diff --git a/programs/pkey/pk_decrypt.c b/programs/pkey/pk_decrypt.c
index 32fbc75..84ed4e9 100644
--- a/programs/pkey/pk_decrypt.c
+++ b/programs/pkey/pk_decrypt.c
@@ -69,7 +69,10 @@
     const char *pers = "mbedtls_pk_decrypt";
     ((void) argv);
 
+    mbedtls_pk_init( &pk );
+    mbedtls_entropy_init( &entropy );
     mbedtls_ctr_drbg_init( &ctr_drbg );
+
     memset(result, 0, sizeof( result ) );
     ret = 1;
 
@@ -87,20 +90,18 @@
     mbedtls_printf( "\n  . Seeding the random number generator..." );
     fflush( stdout );
 
-    mbedtls_entropy_init( &entropy );
-    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
-                               (const unsigned char *) pers,
-                               strlen( pers ) ) ) != 0 )
+    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
+                                       &entropy, (const unsigned char *) pers,
+                                       strlen( pers ) ) ) != 0 )
     {
-        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret );
+        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned -0x%04x\n",
+                        -ret );
         goto exit;
     }
 
     mbedtls_printf( "\n  . Reading private key from '%s'", argv[1] );
     fflush( stdout );
 
-    mbedtls_pk_init( &pk );
-
     if( ( ret = mbedtls_pk_parse_keyfile( &pk, argv[1], "" ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_pk_parse_keyfile returned -0x%04x\n", -ret );
@@ -115,14 +116,16 @@
     if( ( f = fopen( "result-enc.txt", "rb" ) ) == NULL )
     {
         mbedtls_printf( "\n  ! Could not open %s\n\n", "result-enc.txt" );
+        ret = 1;
         goto exit;
     }
 
     i = 0;
-
     while( fscanf( f, "%02X", &c ) > 0 &&
            i < (int) sizeof( buf ) )
+    {
         buf[i++] = (unsigned char) c;
+    }
 
     fclose( f );
 
@@ -135,7 +138,8 @@
     if( ( ret = mbedtls_pk_decrypt( &pk, buf, i, result, &olen, sizeof(result),
                             mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
     {
-        mbedtls_printf( " failed\n  ! mbedtls_pk_decrypt returned -0x%04x\n", -ret );
+        mbedtls_printf( " failed\n  ! mbedtls_pk_decrypt returned -0x%04x\n",
+                        -ret );
         goto exit;
     }
 
@@ -146,13 +150,15 @@
     ret = 0;
 
 exit:
-    mbedtls_ctr_drbg_free( &ctr_drbg );
+
+    mbedtls_pk_free( &pk );
     mbedtls_entropy_free( &entropy );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
 
 #if defined(MBEDTLS_ERROR_C)
     if( ret != 0 )
     {
-        mbedtls_strerror( ret, (char *) buf, sizeof(buf) );
+        mbedtls_strerror( ret, (char *) buf, sizeof( buf ) );
         mbedtls_printf( "  !  Last error was: %s\n", buf );
     }
 #endif
diff --git a/programs/pkey/pk_encrypt.c b/programs/pkey/pk_encrypt.c
index 7ca9d5a..2b6ad52 100644
--- a/programs/pkey/pk_encrypt.c
+++ b/programs/pkey/pk_encrypt.c
@@ -70,6 +70,8 @@
 
     ret = 1;
     mbedtls_ctr_drbg_init( &ctr_drbg );
+    mbedtls_entropy_init( &entropy );
+    mbedtls_pk_init( &pk );
 
     if( argc != 3 )
     {
@@ -85,20 +87,18 @@
     mbedtls_printf( "\n  . Seeding the random number generator..." );
     fflush( stdout );
 
-    mbedtls_entropy_init( &entropy );
-    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
-                               (const unsigned char *) pers,
-                               strlen( pers ) ) ) != 0 )
+    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
+                                       &entropy, (const unsigned char *) pers,
+                                       strlen( pers ) ) ) != 0 )
     {
-        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned -0x%04x\n", -ret );
+        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned -0x%04x\n",
+                        -ret );
         goto exit;
     }
 
     mbedtls_printf( "\n  . Reading public key from '%s'", argv[1] );
     fflush( stdout );
 
-    mbedtls_pk_init( &pk );
-
     if( ( ret = mbedtls_pk_parse_public_keyfile( &pk, argv[1] ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_pk_parse_public_keyfile returned -0x%04x\n", -ret );
@@ -123,7 +123,8 @@
                             buf, &olen, sizeof(buf),
                             mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
     {
-        mbedtls_printf( " failed\n  ! mbedtls_pk_encrypt returned -0x%04x\n", -ret );
+        mbedtls_printf( " failed\n  ! mbedtls_pk_encrypt returned -0x%04x\n",
+                        -ret );
         goto exit;
     }
 
@@ -132,27 +133,32 @@
      */
     if( ( f = fopen( "result-enc.txt", "wb+" ) ) == NULL )
     {
+        mbedtls_printf( " failed\n  ! Could not create %s\n\n",
+                        "result-enc.txt" );
         ret = 1;
-        mbedtls_printf( " failed\n  ! Could not create %s\n\n", "result-enc.txt" );
         goto exit;
     }
 
     for( i = 0; i < olen; i++ )
+    {
         mbedtls_fprintf( f, "%02X%s", buf[i],
                  ( i + 1 ) % 16 == 0 ? "\r\n" : " " );
+    }
 
     fclose( f );
 
     mbedtls_printf( "\n  . Done (created \"%s\")\n\n", "result-enc.txt" );
 
 exit:
-    mbedtls_ctr_drbg_free( &ctr_drbg );
+
+    mbedtls_pk_free( &pk );
     mbedtls_entropy_free( &entropy );
+    mbedtls_ctr_drbg_free( &ctr_drbg );
 
 #if defined(MBEDTLS_ERROR_C)
     if( ret != 0 )
     {
-        mbedtls_strerror( ret, (char *) buf, sizeof(buf) );
+        mbedtls_strerror( ret, (char *) buf, sizeof( buf ) );
         mbedtls_printf( "  !  Last error was: %s\n", buf );
     }
 #endif
diff --git a/programs/test/benchmark.c b/programs/test/benchmark.c
index 0782993..b43816c 100644
--- a/programs/test/benchmark.c
+++ b/programs/test/benchmark.c
@@ -536,7 +536,6 @@
         TIME_AND_TSC( "HMAC_DRBG SHA-1 (NOPR)",
                 if( mbedtls_hmac_drbg_random( &hmac_drbg, buf, BUFSIZE ) != 0 )
                 mbedtls_exit(1) );
-        mbedtls_hmac_drbg_free( &hmac_drbg );
 
         if( mbedtls_hmac_drbg_seed( &hmac_drbg, md_info, myrand, NULL, NULL, 0 ) != 0 )
             mbedtls_exit(1);
@@ -545,7 +544,6 @@
         TIME_AND_TSC( "HMAC_DRBG SHA-1 (PR)",
                 if( mbedtls_hmac_drbg_random( &hmac_drbg, buf, BUFSIZE ) != 0 )
                 mbedtls_exit(1) );
-        mbedtls_hmac_drbg_free( &hmac_drbg );
 #endif
 
 #if defined(MBEDTLS_SHA256_C)
@@ -557,7 +555,6 @@
         TIME_AND_TSC( "HMAC_DRBG SHA-256 (NOPR)",
                 if( mbedtls_hmac_drbg_random( &hmac_drbg, buf, BUFSIZE ) != 0 )
                 mbedtls_exit(1) );
-        mbedtls_hmac_drbg_free( &hmac_drbg );
 
         if( mbedtls_hmac_drbg_seed( &hmac_drbg, md_info, myrand, NULL, NULL, 0 ) != 0 )
             mbedtls_exit(1);
@@ -566,8 +563,8 @@
         TIME_AND_TSC( "HMAC_DRBG SHA-256 (PR)",
                 if( mbedtls_hmac_drbg_random( &hmac_drbg, buf, BUFSIZE ) != 0 )
                 mbedtls_exit(1) );
-        mbedtls_hmac_drbg_free( &hmac_drbg );
 #endif
+        mbedtls_hmac_drbg_free( &hmac_drbg );
     }
 #endif
 
diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 9cc582d..e4f3643 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.c
@@ -161,7 +161,7 @@
     const char *issuer_key;     /* filename of the issuer key file      */
     const char *subject_pwd;    /* password for the subject key file    */
     const char *issuer_pwd;     /* password for the issuer key file     */
-    const char *output_file;    /* where to store the constructed key file  */
+    const char *output_file;    /* where to store the constructed CRT   */
     const char *subject_name;   /* subject name for certificate         */
     const char *issuer_name;    /* issuer name for certificate          */
     const char *not_before;     /* validity period not before           */
@@ -772,7 +772,7 @@
     }
 
     /*
-     * 1.2. Writing the request
+     * 1.2. Writing the certificate
      */
     mbedtls_printf( "  . Writing the certificate..." );
     fflush( stdout );
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 2cbed9d..ea9cafc 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -656,6 +656,22 @@
             -S "SSL - None of the common ciphersuites is usable" \
             -S "SSL - The server has no ciphersuites in common"
 
+# Test empty CA list in CertificateRequest in TLS 1.1 and earlier
+
+requires_gnutls
+requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_1
+run_test    "CertificateRequest with empty CA list, TLS 1.1 (GnuTLS server)" \
+            "$G_SRV"\
+            "$P_CLI force_version=tls1_1" \
+            0
+
+requires_gnutls
+requires_config_enabled MBEDTLS_SSL_PROTO_TLS1
+run_test    "CertificateRequest with empty CA list, TLS 1.0 (GnuTLS server)" \
+            "$G_SRV"\
+            "$P_CLI force_version=tls1" \
+            0
+
 # Tests for SHA-1 support
 
 requires_config_disabled MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES
@@ -1219,6 +1235,71 @@
             -s "session successfully restored from ticket" \
             -s "a session has been resumed"
 
+# Tests for Session Tickets with DTLS
+
+run_test    "Session resume using tickets, DTLS: basic" \
+            "$P_SRV debug_level=3 dtls=1 tickets=1" \
+            "$P_CLI debug_level=3 dtls=1 tickets=1 reconnect=1" \
+            0 \
+            -c "client hello, adding session ticket extension" \
+            -s "found session ticket extension" \
+            -s "server hello, adding session ticket extension" \
+            -c "found session_ticket extension" \
+            -c "parse new session ticket" \
+            -S "session successfully restored from cache" \
+            -s "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using tickets, DTLS: cache disabled" \
+            "$P_SRV debug_level=3 dtls=1 tickets=1 cache_max=0" \
+            "$P_CLI debug_level=3 dtls=1 tickets=1 reconnect=1" \
+            0 \
+            -c "client hello, adding session ticket extension" \
+            -s "found session ticket extension" \
+            -s "server hello, adding session ticket extension" \
+            -c "found session_ticket extension" \
+            -c "parse new session ticket" \
+            -S "session successfully restored from cache" \
+            -s "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using tickets, DTLS: timeout" \
+            "$P_SRV debug_level=3 dtls=1 tickets=1 cache_max=0 ticket_timeout=1" \
+            "$P_CLI debug_level=3 dtls=1 tickets=1 reconnect=1 reco_delay=2" \
+            0 \
+            -c "client hello, adding session ticket extension" \
+            -s "found session ticket extension" \
+            -s "server hello, adding session ticket extension" \
+            -c "found session_ticket extension" \
+            -c "parse new session ticket" \
+            -S "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -S "a session has been resumed" \
+            -C "a session has been resumed"
+
+run_test    "Session resume using tickets, DTLS: openssl server" \
+            "$O_SRV -dtls1" \
+            "$P_CLI dtls=1 debug_level=3 tickets=1 reconnect=1" \
+            0 \
+            -c "client hello, adding session ticket extension" \
+            -c "found session_ticket extension" \
+            -c "parse new session ticket" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using tickets, DTLS: openssl client" \
+            "$P_SRV dtls=1 debug_level=3 tickets=1" \
+            "( $O_CLI -dtls1 -sess_out $SESSION; \
+               $O_CLI -dtls1 -sess_in $SESSION; \
+               rm -f $SESSION )" \
+            0 \
+            -s "found session ticket extension" \
+            -s "server hello, adding session ticket extension" \
+            -S "session successfully restored from cache" \
+            -s "session successfully restored from ticket" \
+            -s "a session has been resumed"
+
 # Tests for Session Resume based on session-ID and cache
 
 run_test    "Session resume using cache: tickets enabled on client" \
@@ -1314,6 +1395,101 @@
             -C "parse new session ticket" \
             -c "a session has been resumed"
 
+# Tests for Session Resume based on session-ID and cache, DTLS
+
+run_test    "Session resume using cache, DTLS: tickets enabled on client" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0" \
+            "$P_CLI dtls=1 debug_level=3 tickets=1 reconnect=1" \
+            0 \
+            -c "client hello, adding session ticket extension" \
+            -s "found session ticket extension" \
+            -S "server hello, adding session ticket extension" \
+            -C "found session_ticket extension" \
+            -C "parse new session ticket" \
+            -s "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: tickets enabled on server" \
+            "$P_SRV dtls=1 debug_level=3 tickets=1" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1" \
+            0 \
+            -C "client hello, adding session ticket extension" \
+            -S "found session ticket extension" \
+            -S "server hello, adding session ticket extension" \
+            -C "found session_ticket extension" \
+            -C "parse new session ticket" \
+            -s "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: cache_max=0" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0 cache_max=0" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1" \
+            0 \
+            -S "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -S "a session has been resumed" \
+            -C "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: cache_max=1" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0 cache_max=1" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1" \
+            0 \
+            -s "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: timeout > delay" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1 reco_delay=0" \
+            0 \
+            -s "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: timeout < delay" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0 cache_timeout=1" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1 reco_delay=2" \
+            0 \
+            -S "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -S "a session has been resumed" \
+            -C "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: no timeout" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0 cache_timeout=0" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1 reco_delay=2" \
+            0 \
+            -s "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -s "a session has been resumed" \
+            -c "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: openssl client" \
+            "$P_SRV dtls=1 debug_level=3 tickets=0" \
+            "( $O_CLI -dtls1 -sess_out $SESSION; \
+               $O_CLI -dtls1 -sess_in $SESSION; \
+               rm -f $SESSION )" \
+            0 \
+            -s "found session ticket extension" \
+            -S "server hello, adding session ticket extension" \
+            -s "session successfully restored from cache" \
+            -S "session successfully restored from ticket" \
+            -s "a session has been resumed"
+
+run_test    "Session resume using cache, DTLS: openssl server" \
+            "$O_SRV -dtls1" \
+            "$P_CLI dtls=1 debug_level=3 tickets=0 reconnect=1" \
+            0 \
+            -C "found session_ticket extension" \
+            -C "parse new session ticket" \
+            -c "a session has been resumed"
+
 # Tests for Max Fragment Length extension
 
 MAX_CONTENT_LEN_EXPECT='16384'
diff --git a/tests/suites/test_suite_version.data b/tests/suites/test_suite_version.data
index bef766c..4db9f94 100644
--- a/tests/suites/test_suite_version.data
+++ b/tests/suites/test_suite_version.data
@@ -1,8 +1,8 @@
 Check compiletime library version
-check_compiletime_version:"2.1.14"
+check_compiletime_version:"2.1.15"
 
 Check runtime library version
-check_runtime_version:"2.1.14"
+check_runtime_version:"2.1.15"
 
 Check for MBEDTLS_VERSION_C
 check_feature:"MBEDTLS_VERSION_C":0
diff --git a/yotta/data/module.json b/yotta/data/module.json
index c27faa3..e9d2578 100644
--- a/yotta/data/module.json
+++ b/yotta/data/module.json
@@ -1,6 +1,6 @@
 {
     "name": "mbedtls",
-    "version": "2.1.14",
+    "version": "2.1.15",
     "description": "The mbed TLS crypto/SSL/TLS library",
     "licenses": [
         {