Merge pull request #690 from ARMmbed/update-development-restricted-20…

…2004329

Merge development into development restricted

.github/issue_template.md

@@ -1,7 +1,7 @@
 Note: This is just a template, so feel free to use/remove the unnecessary things
 
 ### Description
-- Type: Bug | Enhancement\Feature Request | Question
+- Type: Bug | Enhancement\Feature Request
 - Priority: Blocker | Major | Minor
 
 ---------------------------------------------------------------
@@ -38,4 +38,4 @@ Version:
 
 ## Question
 
-**Please first check for answers in the [Mbed TLS knowledge Base](https://tls.mbed.org/kb), and preferably file an issue in the [Mbed TLS support forum](https://forums.mbed.com/c/mbed-tls)**  
+**Please first check for answers in the [Mbed TLS knowledge Base](https://tls.mbed.org/kb). If you can't find the answer you're looking for then please use the [Mbed TLS mailing list](https://lists.trustedfirmware.org/mailman/listinfo/mbed-tls)**

.pylintrc

@@ -40,7 +40,27 @@ max-attributes=15
 max-module-lines=2000
 
 [MESSAGES CONTROL]
-disable=
+# * locally-disabled, locally-enabled: If we disable or enable a message
+#   locally, it's by design. There's no need to clutter the Pylint output
+#   with this information.
+# * logging-format-interpolation: Pylint warns about things like
+#   ``log.info('...'.format(...))``. It insists on ``log.info('...', ...)``.
+#   This is of minor utility (mainly a performance gain when there are
+#   many messages that use formatting and are below the log level).
+#   Some versions of Pylint (including 1.8, which is the version on
+#   Ubuntu 18.04) only recognize old-style format strings using '%',
+#   and complain about something like ``log.info('{}', foo)`` with
+#   logging-too-many-args (Pylint supports new-style formatting if
+#   declared globally with logging_format_style under [LOGGING] but
+#   this requires Pylint >=2.2).
+# * no-else-return: Allow the perfectly reasonable idiom
+#    if condition1:
+#        return value1
+#    else:
+#        return value2
+# * unnecessary-pass: If we take the trouble of adding a line with "pass",
+#   it's because we think the code is clearer that way.
+disable=locally-disabled,locally-enabled,logging-format-interpolation,no-else-return,unnecessary-pass
 
 [REPORTS]
 # Don't diplay statistics. Just the facts.

CMakeLists.txt

@@ -135,7 +135,7 @@ if(CMAKE_COMPILER_IS_GNU)
         set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wlogical-op")
     endif()
     if (GCC_VERSION VERSION_GREATER 4.8 OR GCC_VERSION VERSION_EQUAL 4.8)
-        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wshadow")
+        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wshadow -Wformat-signedness")
     endif()
     set(CMAKE_C_FLAGS_RELEASE     "-O2")
     set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")

ChangeLog

@@ -1,12 +1,22 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
-= mbed TLS x.x.x branch released xxxx-xx-xx
+= mbed TLS 2.22.0 branch released 2020-04-14
 
 New deprecations
    * Deprecate MBEDTLS_SSL_HW_RECORD_ACCEL that enables function hooks in the
      SSL module for hardware acceleration of individual records.
+   * Deprecate mbedtls_ssl_get_max_frag_len() in favour of
+     mbedtls_ssl_get_output_max_frag_len() and
+     mbedtls_ssl_get_input_max_frag_len() to be more precise about which max
+     fragment length is desired.
 
 Security
+   * Fix issue in DTLS handling of new associations with the same parameters
+     (RFC 6347 section 4.2.8): an attacker able to send forged UDP packets to
+     the server could cause it to drop established associations with
+     legitimate clients, resulting in a Denial of Service. This could only
+     happen when MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE was enabled in config.h
+     (which it is by default).
    * Fix side channel in ECC code that allowed an adversary with access to
      precise enough timing and memory access information (typically an
      untrusted operating system attacking a secure enclave) to fully recover
@@ -15,13 +25,27 @@ Security
    * Fix a potentially remotely exploitable buffer overread in a
      DTLS client when parsing the Hello Verify Request message.
 
+Features
+   * The new build option MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH automatically
+     resizes the I/O buffers before and after handshakes, reducing the memory
+     consumption during application data transfer.
+
 Bugfix
    * Fix compilation failure when both MBEDTLS_SSL_PROTO_DTLS and
      MBEDTLS_SSL_HW_RECORD_ACCEL are enabled.
+   * Remove a spurious check in ssl_parse_client_psk_identity that triggered
+     a warning with some compilers. Fix contributed by irwir in #2856.
+   * Fix a function name in a debug message. Contributed by Ercan Ozturk in
+     #3013.
 
 Changes
    * Mbed Crypto is no longer a Git submodule. The crypto part of the library
      is back directly in the present repository.
+   * Split mbedtls_ssl_get_max_frag_len() into
+     mbedtls_ssl_get_output_max_frag_len() and
+     mbedtls_ssl_get_input_max_frag_len() to ensure that a sufficient input
+     buffer is allocated by the server (if MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH
+     is defined), regardless of what MFL was configured for it.
 
 = mbed TLS 2.21.0 branch released 2020-02-20
 

ChangeLog.d/00README.md

@@ -0,0 +1,67 @@
+# Pending changelog entry directory
+
+This directory contains changelog entries that have not yet been merged
+to the changelog file ([`../ChangeLog`](../ChangeLog)).
+
+## Changelog entry file format
+
+A changelog entry file must have the extension `*.txt` and must have the
+following format:
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Security
+   * Change description.
+   * Another change description.
+
+Features
+   * Yet another change description. This is a long change description that
+     spans multiple lines.
+   * Yet again another change description.
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The permitted changelog entry categories are as follows:
+<!-- Keep this synchronized with STANDARD_CATEGORIES in assemble_changelog.py! -->
+
+    API changes
+    Default behavior changes
+    Requirement changes
+    New deprecations
+    Removals
+    Features
+    Security
+    Bugfix
+    Changes
+
+Use “Changes” for anything that doesn't fit in the other categories, such as
+performance, documentation and test improvements.
+
+## How to write a changelog entry
+
+Each entry starts with three spaces, an asterisk and a space. Continuation
+lines start with 5 spaces. Lines wrap at 79 characters.
+
+Write full English sentences with proper capitalization and punctuation. Use
+the present tense. Use the imperative where applicable. For example: “Fix a
+bug in mbedtls_xxx() ….”
+
+Include GitHub issue numbers where relevant. Use the format “#1234” for an
+Mbed TLS issue. Add other external references such as CVE numbers where
+applicable.
+
+Credit the author of the contribution if the contribution is not a member of
+the Mbed TLS development team. Also credit bug reporters where applicable.
+
+**Explain why, not how**. Remember that the audience is the users of the
+library, not its developers. In particular, for a bug fix, explain the
+consequences of the bug, not how the bug was fixed. For a new feature, explain
+why one might be interested in the feature. For an API change or a deprecation,
+explain how to update existing applications.
+
+See [existing entries](../ChangeLog) for examples.
+
+## How `ChangeLog` is updated
+
+Run [`../scripts/assemble_changelog.py`](../scripts/assemble_changelog.py)
+from a Git working copy
+to move the entries from files in `ChangeLog.d` to the main `ChangeLog` file.

ChangeLog.d/bugfix.txt

@@ -0,0 +1,4 @@
+Bugfix
+   * Fix the Visual Studio Release x64 build configuration for mbedtls itself.
+     Completes a previous fix in Mbed TLS 2.19 that only fixed the build for
+     the example programs. Reported in #1430 and fix contributed by irwir.

ChangeLog.d/error_const.txt

@@ -0,0 +1,6 @@
+Features
+   * New functions in the error module return constant strings for
+     high- and low-level error codes, complementing mbedtls_strerror()
+     which constructs a string for any error code, including compound
+     ones, but requires a writable buffer. Contributed by Gaurav Aggarwal
+     in #3176.

ChangeLog.d/fix-ecp_double_add_mxz.txt

@@ -0,0 +1,4 @@
+Changes
+   * Fix minor performance issue in operations on Curve25519 caused by using a
+     suboptimal modular reduction in one place. Found and fix contributed by
+     Aurelien Jarno in #3209.

ChangeLog.d/fix-gcc-format-signedness-warnings.txt

@@ -0,0 +1,3 @@
+Changes
+   * Fix warnings about signedness issues in format strings. The build is now
+     clean of -Wformat-signedness warnings. Contributed by Kenneth Soerensen in #3153.

ChangeLog.d/max_pathlen.txt

@@ -0,0 +1,5 @@
+Bugfix
+   * Fix undefined behavior in X.509 certificate parsing if the
+     pathLenConstraint basic constraint value is equal to INT_MAX.
+     The actual effect with almost every compiler is the intended
+     behavior, so this is unlikely to be exploitable anywhere. #3192

ChangeLog.d/md_switch.txt

@@ -0,0 +1,3 @@
+Changes
+   * Combine identical cases in switch statements in md.c. Contributed
+     by irwir in #3208.

ChangeLog.d/ssl_context_info.txt

@@ -0,0 +1,3 @@
+Features
+   * The new utility programs/ssl/ssl_context_info prints a human-readable
+     dump of an SSL context saved with mbedtls_ssl_context_save().

ChangeLog.d/ssl_write_certificate_request.txt

@@ -0,0 +1,3 @@
+Changes
+   * Simplify a bounds check in ssl_write_certificate_request(). Contributed
+     by irwir in #3150.

Makefile

@@ -124,8 +124,10 @@ endif
 
 ## Editor navigation files
 C_SOURCE_FILES = $(wildcard include/*/*.h library/*.[hc] programs/*/*.[hc] tests/suites/*.function)
+# Exuberant-ctags invocation. Other ctags implementations may require different options.
+CTAGS = ctags --langmap=c:+.h.function -o
 tags: $(C_SOURCE_FILES)
-	ctags -o $@ $(C_SOURCE_FILES)
+	$(CTAGS) $@ $(C_SOURCE_FILES)
 TAGS: $(C_SOURCE_FILES)
 	etags -o $@ $(C_SOURCE_FILES)
 GPATH GRTAGS GSYMS GTAGS: $(C_SOURCE_FILES)

doxygen/input/doc_mainpage.h

@@ -24,7 +24,7 @@
  */
 
 /**
- * @mainpage mbed TLS v2.21.0 source code documentation
+ * @mainpage mbed TLS v2.22.0 source code documentation
  *
  * This documentation describes the internal structure of mbed TLS.  It was
  * automatically generated from specially formatted comment blocks in

doxygen/mbedtls.doxyfile

@@ -28,7 +28,7 @@ DOXYFILE_ENCODING      = UTF-8
 # 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 v2.21.0"
+PROJECT_NAME           = "mbed TLS v2.22.0"
 
 # The PROJECT_NUMBER tag can be used to enter a project or revision number.
 # This could be handy for archiving the generated documentation or
@@ -1594,7 +1594,7 @@ SEARCH_INCLUDES        = YES
 # contain include files that are not input files but should be processed by
 # the preprocessor.
 
-INCLUDE_PATH           =
+INCLUDE_PATH           = ../include
 
 # You can use the INCLUDE_FILE_PATTERNS tag to specify one or more wildcard
 # patterns (like *.h and *.hpp) to filter out the header-files in the

include/mbedtls/check_config.h

@@ -619,6 +619,23 @@
 #error "MBEDTLS_SSL_PROTO_TLS1_2 defined, but not all prerequisites"
 #endif
 
+#if (defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) ||  \
+     defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)) && \
+    !(defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) ||                          \
+      defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) ||                      \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) ||                    \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) ||                  \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) ||                     \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) ||                   \
+      defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) ||                          \
+      defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) ||                      \
+      defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) ||                      \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) ||                    \
+      defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) )
+#error "One or more versions of the TLS protocol are enabled " \
+        "but no key exchange methods defined with MBEDTLS_KEY_EXCHANGE_xxxx"
+#endif
+
 #if defined(MBEDTLS_SSL_PROTO_DTLS)     && \
     !defined(MBEDTLS_SSL_PROTO_TLS1_1)  && \
     !defined(MBEDTLS_SSL_PROTO_TLS1_2)
@@ -763,6 +780,10 @@
 #error "MBEDTLS_X509_CREATE_C defined, but not all prerequisites"
 #endif
 
+#if defined(MBEDTLS_CERTS_C) && !defined(MBEDTLS_X509_USE_C)
+#error "MBEDTLS_CERTS_C defined, but not all prerequisites"
+#endif
+
 #if defined(MBEDTLS_X509_CRT_PARSE_C) && ( !defined(MBEDTLS_X509_USE_C) )
 #error "MBEDTLS_X509_CRT_PARSE_C defined, but not all prerequisites"
 #endif

include/mbedtls/config.h

@@ -1520,8 +1520,8 @@
 
 /** \def MBEDTLS_SSL_EXTENDED_MASTER_SECRET
  *
- * Enable support for Extended Master Secret, aka Session Hash
- * (draft-ietf-tls-session-hash-02).
+ * Enable support for RFC 7627: Session Hash and Extended Master Secret
+ * Extension.
  *
  * This was introduced as "the proper fix" to the Triple Handshake familiy of
  * attacks, but it is recommended to always use it (even if you disable
@@ -1539,7 +1539,8 @@
 /**
  * \def MBEDTLS_SSL_FALLBACK_SCSV
  *
- * Enable support for FALLBACK_SCSV (draft-ietf-tls-downgrade-scsv-00).
+ * Enable support for RFC 7507: Fallback Signaling Cipher Suite Value (SCSV)
+ * for Preventing Protocol Downgrade Attacks.
  *
  * For servers, it is recommended to always enable this, unless you support
  * only one version of TLS, or know for sure that none of your clients

include/mbedtls/error.h

@@ -127,6 +127,36 @@ extern "C" {
  */
 void mbedtls_strerror( int errnum, char *buffer, size_t buflen );
 
+/**
+ * \brief Translate the high-level part of an Mbed TLS error code into a string
+ *        representation.
+ *
+ * This function returns a const pointer to an un-modifiable string. The caller
+ * must not try to modify the string. It is intended to be used mostly for
+ * logging purposes.
+ *
+ * \param error_code    error code
+ *
+ * \return The string representation of the error code, or \c NULL if the error
+ *         code is unknown.
+ */
+const char * mbedtls_high_level_strerr( int error_code );
+
+/**
+ * \brief Translate the low-level part of an Mbed TLS error code into a string
+ *        representation.
+ *
+ * This function returns a const pointer to an un-modifiable string. The caller
+ * must not try to modify the string. It is intended to be used mostly for
+ * logging purposes.
+ *
+ * \param error_code    error code
+ *
+ * \return The string representation of the error code, or \c NULL if the error
+ *         code is unknown.
+ */
+const char * mbedtls_low_level_strerr( int error_code );
+
 #ifdef __cplusplus
 }
 #endif