Secure Socket Layer

Release Notes

Version 8.2.4

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### Chapters

- SSL Release Notes
  - Top of chapter
  - SSL 8.2.4
  - SSL 8.2.3
  - SSL 8.2.2
  - SSL 8.2.1
  - SSL 8.2
  - SSL 8.1.3.1.1
  - SSL 8.1.3.1
  - SSL 8.1.3
  - SSL 8.1.2
  - SSL 8.1.1
  - SSL 8.1
  - SSL 8.0.3
  - SSL 8.0.2
  - SSL 8.0.1
  - SSL 8.0
  - SSL 7.3.3.2
  - SSL 7.3.3
  - SSL 7.3.2
  - SSL 7.3.1
  - SSL 7.3
  - SSL 7.2
  - SSL 7.1
  - SSL 7.0
  - SSL 6.0.1.1
  - SSL 6.0.1
  - SSL 6.0
  - SSL 5.3.8
  - SSL 5.3.7
  - SSL 5.3.6
  - SSL 5.3.5
  - SSL 5.3.4
  - SSL 5.3.3
  - SSL 5.3.2
  - SSL 5.3.1
  - SSL 5.3
  - SSL 5.2.1
  - SSL 5.1.2.1
  - SSL 5.2
  - SSL 5.1.2
  - SSL 5.1.1
  - SSL 5.1
  - SSL 5.0.1
  - SSL 5.0
  - SSL 4.1.6
  - SSL 4.1.5
  - SSL 4.1.3
  - SSL 4.1.2
  - SSL 4.1.1
  - SSL 4.1
  - SSL 4.0.1
  - SSL 4.0

# 1 SSL Release Notes

This document describes the changes made to the SSL application.

### 1.1 SSL 8.2.4

#### Fixed Bugs and Malfunctions

- Optimization of bad merge conflict resolution causing dubble decode

  Own Id: OTP-14843

- Restore error propagation to OTP-19.3 behaviour, in OTP-20.2 implementation adjustments to gen_statem needed some further adjustments to avoid a race condition. This could cause a TLS server to not always report file path errors correctly.

  Own Id: OTP-14852

- Corrected RC4 suites listing function to regard TLS version

  Own Id: OTP-14871

- Fix alert handling so that unexpected messages are logged and alerted correctly

  Own Id: OTP-14919

- Fix alert handling so that unexpected messages are logged and alerted correctly

  Own Id: OTP-14929

- Correct handling of anonymous cipher suites

  Own Id: OTP-14952

#### Improvements and New Features

- Added new API functions to facilitate cipher suite handling

  Own Id: OTP-14760

- Correct TLS_FALLBACK_SCSV handling so that this special flag suite is always placed last in the cipher suite list in accordance with the specs. Also make sure this functionality is used in DTLS.

  Own Id: OTP-14828

- Add TLS record version sanity check for early as possible error detection and consistency in ALERT codes generated

  Own Id: OTP-14892

### 1.2 SSL 8.2.3

#### Fixed Bugs and Malfunctions

- Packet options cannot be supported for unreliable transports, that is, packet option for DTLS over udp will not be supported.

  Own Id: OTP-14664

- Ensure data delivery before close if possible. This fix is related to fix in PR-1479.

  Own Id: OTP-14794

#### Improvements and New Features

- The crypto API is extended to use private/public keys stored in an Engine for sign/verify or encrypt/decrypt operations.

  The ssl application provides an API to use this new engine concept in TLS.

  Own Id: OTP-14448

- Implemented renegotiation for DTLS

  Own Id: OTP-14563

- A new command line option -ssl_dist_optfile has been added to facilitate specifying the many options needed when using SSL as the distribution protocol.

  Own Id: OTP-14657

### 1.3 SSL 8.2.2

#### Fixed Bugs and Malfunctions

- TLS sessions must be registered with SNI if provided, so that sessions where client hostname verification would fail can not connect reusing a session created when the server name verification succeeded.

  Own Id: OTP-14632

- An erlang TLS server configured with cipher suites using rsa key exchange, may be vulnerable to an Adaptive Chosen Ciphertext attack (AKA Bleichenbacher attack) against RSA, which when exploited, may result in plaintext recovery of encrypted messages and/or a Man-in-the-middle (MiTM) attack, despite the attacker not having gained access to the server’s private key itself. CVE-2017-1000385

  Exploiting this vulnerability to perform plaintext recovery of encrypted messages will, in most practical cases, allow an attacker to read the plaintext only after the session has completed. Only TLS sessions established using RSA key exchange are vulnerable to this attack.

  Exploiting this vulnerability to conduct a MiTM attack requires the attacker to complete the initial attack, which may require thousands of server requests, during the handshake phase of the targeted session within the window of the configured handshake timeout. This attack may be conducted against any TLS session using RSA signatures, but only if cipher suites using RSA key exchange are also enabled on the server. The limited window of opportunity, limitations in bandwidth, and latency make this attack significantly more difficult to execute.

  RSA key exchange is enabled by default although least prioritized if server order is honored. For such a cipher suite to be chosen it must also be supported by the client and probably the only shared cipher suite.

  Captured TLS sessions encrypted with ephemeral cipher suites (DHE or ECDHE) are not at risk for subsequent decryption due to this vulnerability.

  As a workaround if default cipher suite configuration was used you can configure the server to not use vulnerable suites with the ciphers option like this:

  {ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,Suite) =/= rsa]}

  that is your code will look somethingh like this:

  ssl:listen(Port, [{ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,S) =/= rsa]} | Options]).

  Thanks to Hanno Böck, Juraj Somorovsky and Craig Young for reporting this vulnerability.

  Own Id: OTP-14748

#### Improvements and New Features

- If no SNI is available and the hostname is an IP-address also check for IP-address match. This check is not as good as a DNS hostname check and certificates using IP-address are not recommended.

  Own Id: OTP-14655

### 1.4 SSL 8.2.1

#### Fixed Bugs and Malfunctions

- Max session table works correctly again

  Own Id: OTP-14556

#### Improvements and New Features

- Customize alert handling for DTLS over UDP to mitigate DoS attacks

  Own Id: OTP-14078

- Improved error propagation and reports

  Own Id: OTP-14236

### 1.5 SSL 8.2

#### Fixed Bugs and Malfunctions

- ECDH-ECDSA key exchange supported, was accidently dismissed in earlier versions.

  Own Id: OTP-14421

- Correct close semantics for active once connections. This was a timing dependent bug the resulted in the close message not always reaching the ssl user process.

  Own Id: OTP-14443

#### Improvements and New Features

- TLS-1.2 clients will now always send hello messages on its own format, as opposed to earlier versions that will send the hello on the lowest supported version, this is a change supported by the latest RFC.

  This will make interoperability with some newer servers smoother. Potentially, but unlikely, this could cause a problem with older servers if they do not adhere to the RFC and ignore unknown extensions.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13820

- Allow Erlang/OTP to use OpenSSL in FIPS-140 mode, in order to satisfy specific security requirements (mostly by different parts of the US federal government).

  See the new crypto users guide "FIPS mode" chapter about building and using the FIPS support which is disabled by default.

  (Thanks to dszoboszlay and legoscia)

  Own Id: OTP-13921 Aux Id: PR-1180

- Implemented DTLS cookie generation, required by spec, instead of using a hardcoded value.

  Own Id: OTP-14076

- Implement sliding window replay protection of DTLS records.

  Own Id: OTP-14077

- TLS client processes will by default call public_key:pkix_verify_hostname/2 to verify the hostname of the connection with the server certificates specified hostname during certificate path validation. The user may explicitly disables it. Also if the hostname can not be derived from the first argument to connect or is not supplied by the server name indication option, the check will not be performed.

  Own Id: OTP-14197

- Extend connection_information/[1,2] . The values session_id, master_secret, client_random and server_random can no be accessed by connection_information/2. Note only session_id will be added to connection_information/1. The rational is that values concerning the connection security should have to be explicitly requested.

  Own Id: OTP-14291

- Chacha cipher suites are currently not tested enough to be most preferred ones

  Own Id: OTP-14382

- Basic support for DTLS that been tested together with OpenSSL.

  Test by providing the option {protocol, dtls} to the ssl API functions connect and listen.

  Own Id: OTP-14388

### 1.6 SSL 8.1.3.1.1

#### Fixed Bugs and Malfunctions

- Fix alert handling so that unexpected messages are logged and alerted correctly

  Own Id: OTP-14929

### 1.7 SSL 8.1.3.1

#### Fixed Bugs and Malfunctions

- An erlang TLS server configured with cipher suites using rsa key exchange, may be vulnerable to an Adaptive Chosen Ciphertext attack (AKA Bleichenbacher attack) against RSA, which when exploited, may result in plaintext recovery of encrypted messages and/or a Man-in-the-middle (MiTM) attack, despite the attacker not having gained access to the server’s private key itself. CVE-2017-1000385

  Exploiting this vulnerability to perform plaintext recovery of encrypted messages will, in most practical cases, allow an attacker to read the plaintext only after the session has completed. Only TLS sessions established using RSA key exchange are vulnerable to this attack.

  Exploiting this vulnerability to conduct a MiTM attack requires the attacker to complete the initial attack, which may require thousands of server requests, during the handshake phase of the targeted session within the window of the configured handshake timeout. This attack may be conducted against any TLS session using RSA signatures, but only if cipher suites using RSA key exchange are also enabled on the server. The limited window of opportunity, limitations in bandwidth, and latency make this attack significantly more difficult to execute.

  RSA key exchange is enabled by default although least prioritized if server order is honored. For such a cipher suite to be chosen it must also be supported by the client and probably the only shared cipher suite.

  Captured TLS sessions encrypted with ephemeral cipher suites (DHE or ECDHE) are not at risk for subsequent decryption due to this vulnerability.

  As a workaround if default cipher suite configuration was used you can configure the server to not use vulnerable suites with the ciphers option like this:

  {ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,Suite) =/= rsa]}

  that is your code will look somethingh like this:

  ssl:listen(Port, [{ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,S) =/= rsa]} | Options]).

  Thanks to Hanno Böck, Juraj Somorovsky and Craig Young for reporting this vulnerability.

  Own Id: OTP-14748

### 1.8 SSL 8.1.3

#### Fixed Bugs and Malfunctions

- Remove debug printout

  Own Id: OTP-14396

### 1.9 SSL 8.1.2

#### Fixed Bugs and Malfunctions

- Correct active once emulation, for TLS. Now all data received by the connection process will be delivered through active once, even when the active once arrives after that the gen_tcp socket is closed by the peer.

  Own Id: OTP-14300

### 1.10 SSL 8.1.1

#### Fixed Bugs and Malfunctions

- Corrected termination behavior, that caused a PEM cache bug and sometimes resulted in connection failures.

  Own Id: OTP-14100

- Fix bug that could hang ssl connection processes when failing to require more data for very large handshake packages. Add option max_handshake_size to mitigate DoS attacks.

  Own Id: OTP-14138

- Improved support for CRL handling that could fail to work as intended when an id-ce-extKeyUsage was present in the certificate. Also improvements where needed to distributionpoint handling so that all revocations actually are found and not deemed to be not determinable.

  Own Id: OTP-14141

- A TLS handshake might accidentally match old sslv2 format and ssl application would incorrectly aborted TLS handshake with ssl_v2_client_hello_no_supported. Parsing was altered to avoid this problem.

  Own Id: OTP-14222

- Correct default cipher list to prefer AES 128 before 3DES

  Own Id: OTP-14235

#### Improvements and New Features

- Move PEM cache to a dedicated process, to avoid making the SSL manager process a bottleneck. This improves scalability of TLS connections.

  Own Id: OTP-13874

### 1.11 SSL 8.1

#### Fixed Bugs and Malfunctions

- List of possible anonymous suites, never supported by default, where incorrect for some TLS versions.

  Own Id: OTP-13926

#### Improvements and New Features

- Experimental version of DTLS. It is runnable but not complete and cannot be considered reliable for production usage.

  Own Id: OTP-12982

- Add API options to handle ECC curve selection.

  Own Id: OTP-13959

### 1.12 SSL 8.0.3

#### Fixed Bugs and Malfunctions

- A timing related bug in event handling could cause interoperability problems between an erlang TLS server and some TLS clients, especially noticed with Firefox as TLS client.

  Own Id: OTP-13917

- Correct ECC curve selection, the error could cause the default to always be selected.

  Own Id: OTP-13918

### 1.13 SSL 8.0.2

#### Fixed Bugs and Malfunctions

- Correctly formed handshake messages received out of order will now correctly fail the connection with unexpected message.

  Own Id: OTP-13853

- Correct handling of signature algorithm selection

  Own Id: OTP-13711

#### Improvements and New Features

- ssl application now behaves gracefully also on partially incorrect input from peer.

  Own Id: OTP-13834

- Add application environment configuration bypass_pem_cache. This can be used as a workaround for the current implementation of the PEM-cache that has proven to be a bottleneck.

  Own Id: OTP-13883

### 1.14 SSL 8.0.1

#### Fixed Bugs and Malfunctions

- The TLS/SSL protocol version selection for the SSL server has been corrected to follow RFC 5246 Appendix E.1 especially in case where the list of supported versions has gaps. Now the server selects the highest protocol version it supports that is not higher than what the client supports.

  Own Id: OTP-13753 Aux Id: seq13150

### 1.15 SSL 8.0

#### Fixed Bugs and Malfunctions

- Server now rejects, a not requested client cert, as an incorrect handshake message and ends the connection.

  Own Id: OTP-13651

#### Improvements and New Features

- Remove default support for DES cipher suites

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13195

- Deprecate the function crypto:rand_bytes and make sure that crypto:strong_rand_bytes is used in all places that are cryptographically significant.

  Own Id: OTP-13214

- Better error handling of user error during TLS upgrade. ERL-69 is solved by gen_statem rewrite of ssl application.

  Own Id: OTP-13255

- Provide user friendly error message when crypto rejects a key

  Own Id: OTP-13256

- Add ssl:getstat/1 and ssl:getstat/2

  Own Id: OTP-13415

- TLS distribution connections now allow specifying the options verify_fun, crl_check and crl_cache. See the documentation. GitHub pull req #956 contributed by Magnus Henoch.

  Own Id: OTP-13429 Aux Id: Pull#956

- Remove confusing error message when closing a distributed erlang node running over TLS

  Own Id: OTP-13431

- Remove default support for use of md5 in TLS 1.2 signature algorithms

  Own Id: OTP-13463

- ssl now uses gen_statem instead of gen_fsm to implement the ssl connection process, this solves some timing issues in addition to making the code more intuitive as the behaviour can be used cleanly instead of having a lot of workaround for shortcomings of the behaviour.

  Own Id: OTP-13464

- Phase out interoperability with clients that offer SSLv2. By default they are no longer supported, but an option to provide interoperability is offered.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-13465

- OpenSSL has functions to generate short (eight hex digits) hashes of issuers of certificates and CRLs. These hashes are used by the "c_rehash" script to populate directories of CA certificates and CRLs, e.g. in the Apache web server. Add functionality to let an Erlang program find the right CRL for a given certificate in such a directory.

  Own Id: OTP-13530

- Some legacy TLS 1.0 software does not tolerate the 1/n-1 content split BEAST mitigation technique. Add a beast_mitigation SSL option (defaulting to one_n_minus_one) to select or disable the BEAST mitigation technique.

  Own Id: OTP-13629

- Enhance error log messages to facilitate for users to understand the error

  Own Id: OTP-13632

- Increased default DH params to 2048-bit

  Own Id: OTP-13636

- Propagate CRL unknown CA error so that public_key validation process continues correctly and determines what should happen.

  Own Id: OTP-13656

- Introduce a flight concept for handshake packages. This is a preparation for enabling DTLS, however it can also have a positive effects for TLS on slow and unreliable networks.

  Own Id: OTP-13678

### 1.16 SSL 7.3.3.2

#### Fixed Bugs and Malfunctions

- An erlang TLS server configured with cipher suites using rsa key exchange, may be vulnerable to an Adaptive Chosen Ciphertext attack (AKA Bleichenbacher attack) against RSA, which when exploited, may result in plaintext recovery of encrypted messages and/or a Man-in-the-middle (MiTM) attack, despite the attacker not having gained access to the server’s private key itself. CVE-2017-1000385

  Exploiting this vulnerability to perform plaintext recovery of encrypted messages will, in most practical cases, allow an attacker to read the plaintext only after the session has completed. Only TLS sessions established using RSA key exchange are vulnerable to this attack.

  Exploiting this vulnerability to conduct a MiTM attack requires the attacker to complete the initial attack, which may require thousands of server requests, during the handshake phase of the targeted session within the window of the configured handshake timeout. This attack may be conducted against any TLS session using RSA signatures, but only if cipher suites using RSA key exchange are also enabled on the server. The limited window of opportunity, limitations in bandwidth, and latency make this attack significantly more difficult to execute.

  RSA key exchange is enabled by default although least prioritized if server order is honored. For such a cipher suite to be chosen it must also be supported by the client and probably the only shared cipher suite.

  Captured TLS sessions encrypted with ephemeral cipher suites (DHE or ECDHE) are not at risk for subsequent decryption due to this vulnerability.

  As a workaround if default cipher suite configuration was used you can configure the server to not use vulnerable suites with the ciphers option like this:

  {ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,Suite) =/= rsa]}

  that is your code will look somethingh like this:

  ssl:listen(Port, [{ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,S) =/= rsa]} | Options]).

  Thanks to Hanno Böck, Juraj Somorovsky and Craig Young for reporting this vulnerability.

  Own Id: OTP-14748

### 1.17 SSL 7.3.3

#### Fixed Bugs and Malfunctions

- Correct ssl:prf/5 to use the negotiated cipher suite's prf function in ssl:prf/5 instead of the default prf.

  Own Id: OTP-13546

- Timeouts may have the value 0, guards have been corrected to allow this

  Own Id: OTP-13635

- Change of internal handling of hash sign pairs as the used one enforced to much restrictions making some valid combinations unavailable.

  Own Id: OTP-13670

#### SSL 7.3.3.0.1

##### Fixed Bugs and Malfunctions

- An erlang TLS server configured with cipher suites using rsa key exchange, may be vulnerable to an Adaptive Chosen Ciphertext attack (AKA Bleichenbacher attack) against RSA, which when exploited, may result in plaintext recovery of encrypted messages and/or a Man-in-the-middle (MiTM) attack, despite the attacker not having gained access to the server’s private key itself. CVE-2017-1000385

  Exploiting this vulnerability to perform plaintext recovery of encrypted messages will, in most practical cases, allow an attacker to read the plaintext only after the session has completed. Only TLS sessions established using RSA key exchange are vulnerable to this attack.

  Exploiting this vulnerability to conduct a MiTM attack requires the attacker to complete the initial attack, which may require thousands of server requests, during the handshake phase of the targeted session within the window of the configured handshake timeout. This attack may be conducted against any TLS session using RSA signatures, but only if cipher suites using RSA key exchange are also enabled on the server. The limited window of opportunity, limitations in bandwidth, and latency make this attack significantly more difficult to execute.

  RSA key exchange is enabled by default although least prioritized if server order is honored. For such a cipher suite to be chosen it must also be supported by the client and probably the only shared cipher suite.

  Captured TLS sessions encrypted with ephemeral cipher suites (DHE or ECDHE) are not at risk for subsequent decryption due to this vulnerability.

  As a workaround if default cipher suite configuration was used you can configure the server to not use vulnerable suites with the ciphers option like this:

  {ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,Suite) =/= rsa]}

  that is your code will look somethingh like this:

  ssl:listen(Port, [{ciphers, [Suite || Suite <- ssl:cipher_suites(), element(1,S) =/= rsa]} | Options]).

  Thanks to Hanno Böck, Juraj Somorovsky and Craig Young for reporting this vulnerability.

  Own Id: OTP-14748

#### Improvements and New Features

- Create a little randomness in sending of session invalidation messages, to mitigate load when whole table is invalidated.

  Own Id: OTP-13490

### 1.18 SSL 7.3.2

#### Fixed Bugs and Malfunctions

- Correct cipher suites conversion and gaurd expression. Caused problems with GCM cipher suites and client side option to set signature_algorithms extention values.

  Own Id: OTP-13525

### 1.19 SSL 7.3.1

#### Fixed Bugs and Malfunctions

- Corrections to cipher suite handling using the 3 and 4 tuple format in addition to commit 89d7e21cf4ae988c57c8ef047bfe85127875c70c

  Own Id: OTP-13511

#### Improvements and New Features

- Make values for the TLS-1.2 signature_algorithms extension configurable

  Own Id: OTP-13261

### 1.20 SSL 7.3

#### Fixed Bugs and Malfunctions

- Make sure there is only one poller validator at a time for validating the session cache.

  Own Id: OTP-13185

- A timing related issue could cause ssl to hang, especially happened with newer versions of OpenSSL in combination with ECC ciphers.

  Own Id: OTP-13253

- Work around a race condition in the TLS distribution start.

  Own Id: OTP-13268

- Big handshake messages are now correctly fragmented in the TLS record layer.

  Own Id: OTP-13306

- Improve portability of ECC tests in Crypto and SSL for "exotic" OpenSSL versions.

  Own Id: OTP-13311

- Certificate extensions marked as critical are ignored when using verify_none

  Own Id: OTP-13377

- If a certificate doesn't contain a CRL Distribution Points extension, and the relevant CRL is not in the cache, and the crl_check option is not set to best_effort , the revocation check should fail.

  Own Id: OTP-13378

- Enable TLS distribution over IPv6

  Own Id: OTP-13391

#### Improvements and New Features

- Improve error reporting for TLS distribution

  Own Id: OTP-13219

- Include options from connect, listen and accept in connection_information/1,2

  Own Id: OTP-13232

- Allow adding extra options for outgoing TLS distribution connections, as supported for plain TCP connections.

  Own Id: OTP-13285

- Use loopback as server option in TLS-distribution module

  Own Id: OTP-13300

- Verify certificate signature against original certificate binary.

  This avoids bugs due to encoding errors when re-encoding a decode certificate. As there exists several decode step and using of different ASN.1 specification this is a risk worth avoiding.

  Own Id: OTP-13334

- Use application:ensure_all_started/2 instead of hard-coding dependencies

  Own Id: OTP-13363

### 1.21 SSL 7.2

#### Fixed Bugs and Malfunctions

- Honor distribution port range options

  Own Id: OTP-12838

- Correct supervisor specification in TLS distribution.

  Own Id: OTP-13134

- Correct cache timeout

  Own Id: OTP-13141

- Avoid crash and restart of ssl process when key file does not exist.

  Own Id: OTP-13144

- Enable passing of raw socket options on the format {raw,_,_,_} to the underlying socket.

  Own Id: OTP-13166

- Hibernation with small or a zero timeout will now work as expected

  Own Id: OTP-13189

#### Improvements and New Features

- Add upper limit for session cache, configurable on ssl application level.

  If upper limit is reached, invalidate the current cache entries, e.i the session lifetime is the max time a session will be keept, but it may be invalidated earlier if the max limit for the table is reached. This will keep the ssl manager process well behaved, not exhusting memeory. Invalidating the entries will incrementally empty the cache to make room for fresh sessions entries.

  Own Id: OTP-12392

- Use new time functions to measure passed time.

  Own Id: OTP-12457

- Improved error handling in TLS distribution

  Own Id: OTP-13142

- Distribution over TLS now honors the nodelay distribution flag

  Own Id: OTP-13143

### 1.22 SSL 7.1

#### Fixed Bugs and Malfunctions

- Add DER encoded ECPrivateKey as valid input format for key option.

  Own Id: OTP-12974

- Correct return value of default session callback module

  This error had the symptom that the client check for unique session would always fail, potentially making the client session table grow a lot and causing long setup times.

  Own Id: OTP-12980

#### Improvements and New Features

- Add possibility to downgrade an SSL/TLS connection to a tcp connection, and give back the socket control to a user process.

  This also adds the possibility to specify a timeout to the ssl:close function.

  Own Id: OTP-11397

- Add application setting to be able to change fatal alert shutdown timeout, also shorten the default timeout. The fatal alert timeout is the number of milliseconds between sending of a fatal alert and closing the connection. Waiting a little while improves the peers chances to properly receiving the alert so it may shutdown gracefully.

  Own Id: OTP-12832

### 1.23 SSL 7.0

#### Fixed Bugs and Malfunctions

- Ignore signature_algorithm (TLS 1.2 extension) sent to TLS 1.0 or TLS 1.1 server

  Own Id: OTP-12670

- Improve error handling in TLS distribution module to avoid lingering sockets.

  Own Id: OTP-12799 Aux Id: Tom Briden

- Add option {client_renegotiation, boolean()} option to the server-side of the SSL application.

  Own Id: OTP-12815

#### Improvements and New Features

- Add new API functions to handle CRL-verification

  Own Id: OTP-10362 Aux Id: kunagi-215 [126]

- Remove default support for SSL-3.0, due to Poodle vunrability in protocol specification.

  Add padding check for TLS-1.0 to remove Poodle vunrability from TLS 1.0, also add the option padding_check. This option only affects TLS-1.0 connections and if set to false it disables the block cipher padding check to be able to interoperate with legacy software.

  Remove default support for RC4 cipher suites, as they are consider too weak.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-12390

- Add support for TLS ALPN (Application-Layer Protocol Negotiation) extension.

  Own Id: OTP-12580

- Add SNI (Server Name Indication) support for the server side.

  Own Id: OTP-12736

### 1.24 SSL 6.0.1.1

#### Fixed Bugs and Malfunctions

- Gracefully ignore proprietary hash_sign algorithms

  Own Id: OTP-12829

### 1.25 SSL 6.0.1

#### Fixed Bugs and Malfunctions

- Terminate gracefully when receving bad input to premaster secret calculation

  Own Id: OTP-12783

### 1.26 SSL 6.0

#### Fixed Bugs and Malfunctions

- Exclude self-signed trusted anchor certificates from certificate prospective certification path according to RFC 3280.

  This will avoid some unnecessary certificate processing.

  Own Id: OTP-12449

#### Improvements and New Features

- Separate client and server session cache internally.

  Avoid session table growth when client starts many connections in such a manner that many connections are started before session reuse is possible. Only save a new session in client if there is no equivalent session already stored.

  Own Id: OTP-11365

- The PEM cache is now validated by a background process, instead of always keeping it if it is small enough and clearing it otherwise. That strategy required that small caches where cleared by API function if a file changes on disk.

  However export the API function to clear the cache as it may still be useful.

  Own Id: OTP-12391

- Add padding check for TLS-1.0 to remove Poodle vulnerability from TLS 1.0, also add the option padding_check. This option only affects TLS-1.0 connections and if set to false it disables the block cipher padding check to be able to interoperate with legacy software.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-12420

- Add support for TLS_FALLBACK_SCSV used to prevent undesired TLS version downgrades. If used by a client that is vulnerable to the POODLE attack, and the server also supports TLS_FALLBACK_SCSV, the attack can be prevented.

  Own Id: OTP-12458

### 1.27 SSL 5.3.8

#### Fixed Bugs and Malfunctions

- Make sure the clean rule for ssh, ssl, eunit and otp_mibs actually removes generated files.

  Own Id: OTP-12200

#### Improvements and New Features

- Change code to reflect that state data may be secret to avoid breaking dialyzer contracts.

  Own Id: OTP-12341

### 1.28 SSL 5.3.7

#### Fixed Bugs and Malfunctions

- Handle the fact that servers may send an empty SNI extension to the client.

  Own Id: OTP-12198

### 1.29 SSL 5.3.6

#### Fixed Bugs and Malfunctions

- Corrected handling of ECC certificates, there where several small issues with the handling of such certificates in the ssl and public_key application. Now ECC signed ECC certificates shall work and not only RSA signed ECC certificates.

  Own Id: OTP-12026

- Check that the certificate chain ends with a trusted ROOT CA e.i. a self-signed certificate, but provide an option partial_chain to enable the application to define an intermediat CA as trusted.

  Own Id: OTP-12149

#### Improvements and New Features

- Add decode functions for SNI (Server Name Indication)

  Own Id: OTP-12048

### 1.30 SSL 5.3.5

#### Fixed Bugs and Malfunctions

- ssl:recv now returns {error, einval} if applied to a non passive socket, the same as gen_tcp:recv.

  Thanks to Danil Zagoskin for reporting this issue

  Own Id: OTP-11878

- Corrected handling of default values for signature_algorithms extension in TLS-1.2 and corresponding values used in previous versions that does not support this extension.

  Thanks to Danil Zagoskin

  Own Id: OTP-11886

- Handle socket option inheritance when pooling of accept sockets is used

  Own Id: OTP-11897

- Make sure that the list of versions, possibly supplied in the versions option, is not order dependent.

  Thanks to Ransom Richardson for reporting this issue

  Own Id: OTP-11912

- Reject connection if the next_protocol message is sent twice.

  Own Id: OTP-11926

- Correct options handling when ssl:ssl_accept/3 is called with new ssl options after calling ssl:listen/2

  Own Id: OTP-11950

#### Improvements and New Features

- Gracefully handle unknown alerts

  Thanks to Atul Atri for reporting this issue

  Own Id: OTP-11874

- Gracefully ignore cipher suites sent by client not supported by the SSL/TLS version that the client has negotiated.

  Thanks to Danil Zagoskin for reporting this issue

  Own Id: OTP-11875

- Gracefully handle structured garbage, i.e a client sends some garbage in a ssl record instead of a valid fragment.

  Thanks to Danil Zagoskin

  Own Id: OTP-11880

- Gracefully handle invalid alerts

  Own Id: OTP-11890

- Generalize handling of default ciphers

  Thanks to Andreas Schultz

  Own Id: OTP-11966

- Make sure change cipher spec is correctly handled

  Own Id: OTP-11975

### 1.31 SSL 5.3.4

#### Fixed Bugs and Malfunctions

- Fix incorrect dialyzer spec and types, also enhance documentation.

  Thanks to Ayaz Tuncer.

  Own Id: OTP-11627

- Fix possible mismatch between SSL/TLS version and default ciphers. Could happen when you specified SSL/TLS-version in optionlist to listen or accept.

  Own Id: OTP-11712

- Application upgrade (appup) files are corrected for the following applications:

  asn1, common_test, compiler, crypto, debugger, dialyzer, edoc, eldap, erl_docgen, et, eunit, gs, hipe, inets, observer, odbc, os_mon, otp_mibs, parsetools, percept, public_key, reltool, runtime_tools, ssh, syntax_tools, test_server, tools, typer, webtool, wx, xmerl

  A new test utility for testing appup files is added to test_server. This is now used by most applications in OTP.

  (Thanks to Tobias Schlager)

  Own Id: OTP-11744

#### Improvements and New Features

- Moved elliptic curve definition from the crypto NIF/OpenSSL into Erlang code, adds the RFC-5639 brainpool curves and makes TLS use them (RFC-7027).

  Thanks to Andreas Schultz

  Own Id: OTP-11578

- Unicode adaptations

  Own Id: OTP-11620

- Added option honor_cipher_order. This instructs the server to prefer its own cipher ordering rather than the client's and can help protect against things like BEAST while maintaining compatability with clients which only support older ciphers.

  Thanks to Andrew Thompson for the implementation, and Andreas Schultz for the test cases.

  Own Id: OTP-11621

- Replace boolean checking in validate_option with is_boolean guard.

  Thanks to Andreas Schultz.

  Own Id: OTP-11634

- Some function specs are corrected or moved and some edoc comments are corrected in order to allow use of edoc. (Thanks to Pierre Fenoll)

  Own Id: OTP-11702

- Correct clean up of certificate database when certs are inputed in pure DER format.The incorrect code could cause a memory leek when certs where inputed in DER. Thanks to Bernard Duggan for reporting this.

  Own Id: OTP-11733

- Improved documentation of the cacertfile option

  Own Id: OTP-11759 Aux Id: seq12535

- Avoid next protocol negotiation failure due to incorrect option format.

  Own Id: OTP-11760

- Handle v1 CRLs, with no extensions and fixes issues with IDP (Issuing Distribution Point) comparison during CRL validation.

  Thanks to Andrew Thompson

  Own Id: OTP-11761

- Server now ignores client ECC curves that it does not support instead of crashing.

  Thanks to Danil Zagoskin for reporting the issue and suggesting a solution.

  Own Id: OTP-11780

- Handle SNI (Server Name Indication) alert unrecognized_name and gracefully deal with unexpected alerts.

  Thanks to Masatake Daimon for reporting this.

  Own Id: OTP-11815

- Add possibility to specify ssl options when calling ssl:ssl_accept

  Own Id: OTP-11837

### 1.32 SSL 5.3.3

#### Fixed Bugs and Malfunctions

- Add missing validation of the server_name_indication option and test for its explicit use. It was not possible to set or disable the default server_name_indication as the validation of the option was missing.

  Own Id: OTP-11567

- Elliptic curve selection in server mode now properly selects a curve suggested by the client, if possible, and the fallback alternative is changed to a more widely supported curve.

  Own Id: OTP-11575

- Bug in the TLS hello extension handling caused the server to behave as it did not understand secure renegotiation.

  Own Id: OTP-11595

### 1.33 SSL 5.3.2

#### Fixed Bugs and Malfunctions

- Honors the clients advertised support of elliptic curves and no longer sends incorrect elliptic curve extension in server hello.

  Own Id: OTP-11370

- Fix initialization of DTLS fragment reassembler, in previously contributed code, for future support of DTLS . Thanks to Andreas Schultz.

  Own Id: OTP-11376

- Corrected type error in client_preferred_next_protocols documentation. Thanks to Julien Barbot.

  Own Id: OTP-11457

#### Improvements and New Features

- TLS code has been refactored to prepare for future DTLS support. Also some DTLS code is in place but not yet runnable, some of it contributed by Andreas Schultz and some of it written by the OTP team. Thanks to to Andreas for his participation.

  Own Id: OTP-11292

- Remove extraneous dev debug code left in the close function. Thanks to Ken Key.

  Own Id: OTP-11447

- Add SSL Server Name Indication (SNI) client support. Thanks to Julien Barbot.

  Own Id: OTP-11460

### 1.34 SSL 5.3.1

#### Fixed Bugs and Malfunctions

- Setopts during renegotiation caused the renegotiation to be unsuccessful.

  If calling setopts during a renegotiation the FSM state might change during the handling of the setopts messages, this is now handled correctly.

  Own Id: OTP-11228

- Now handles signature_algorithm field in digitally_signed properly with proper defaults. Prior to this change some elliptic curve cipher suites could fail reporting the error "bad certificate".

  Own Id: OTP-11229

- The code emulating the inet header option was changed in the belief that it made it inet compatible. However the testing is a bit hairy as the inet option is actually broken, now the tests are corrected and the header option should work in the same broken way as inet again, preferably use the bitsyntax instead.

  Own Id: OTP-11230

#### Improvements and New Features

- Make the ssl manager name for erlang distribution over SSL/TLS relative to the module name of the ssl_manager.

  This can be beneficial when making tools that rename modules for internal processing in the tool.

  Own Id: OTP-11255

- Add documentation regarding log_alert option.

  Own Id: OTP-11271

### 1.35 SSL 5.3

#### Fixed Bugs and Malfunctions

- Honor the versions option to ssl:connect and ssl:listen.

  Own Id: OTP-10905

- Next protocol negotiation with reused sessions will now succeed

  Own Id: OTP-10909

#### Improvements and New Features

- Add support for PSK (Pre Shared Key) and SRP (Secure Remote Password) chipher suits, thanks to Andreas Schultz.

  Own Id: OTP-10450 Aux Id: kunagi-269 [180]

- Fix SSL Next Protocol Negotiation documentation. Thanks to Julien Barbot.

  Own Id: OTP-10955

- Fix ssl_connection to support reading proxy/chain certificates. Thanks to Valentin Kuznetsov.

  Own Id: OTP-10980

- Integrate elliptic curve contribution from Andreas Schultz

  In order to be able to support elliptic curve cipher suites in SSL/TLS, additions to handle elliptic curve infrastructure has been added to public_key and crypto.

  This also has resulted in a rewrite of the crypto API to gain consistency and remove unnecessary overhead. All OTP applications using crypto has been updated to use the new API.

  Impact: Elliptic curve cryptography (ECC) offers equivalent security with smaller key sizes than other public key algorithms. Smaller key sizes result in savings for power, memory, bandwidth, and computational cost that make ECC especially attractive for constrained environments.

  Own Id: OTP-11009

### 1.36 SSL 5.2.1

#### Improvements and New Features

- Transport callback handling is changed so that gen_tcp is treated as a special case where inet will be called directly for functions such as setopts, as gen_tcp does not have its own setopts. This will enable users to use the transport callback for other customizations such as websockets.

  Own Id: OTP-10847

- Follow up to OTP-10451 solved in ssl-5.2 R16A. Make sure format_error return good strings. Replace confusing legacy atoms with more descriptive atoms.

  Own Id: OTP-10864

### 1.37 SSL 5.1.2.1

#### Improvements and New Features

- Make log_alert configurable as option in ssl, SSLLogLevel added as option to inets conf file

  Own Id: OTP-11259

### 1.38 SSL 5.2

#### Fixed Bugs and Malfunctions

- SSL: TLS 1.2, advertise sha224 support, thanks to Andreas Schultz.

  Own Id: OTP-10586

- If an ssl server is restarted with new options and a client tries to reuse a session the server must make sure that it complies to the new options before agreeing to reuse it.

  Own Id: OTP-10595

- Now handles cleaning of CA-certificate database correctly so that there will be no memory leek, bug was introduced in ssl- 5.1 when changing implementation to increase parallel execution.

  Impact: Improved memory usage, especially if you have many different certificates and upgrade tcp-connections to TLS-connections.

  Own Id: OTP-10710

#### Improvements and New Features

- Support Next Protocol Negotiation in TLS, thanks to Ben Murphy for the contribution.

  Impact: Could give performance benefit if used as it saves a round trip.

  Own Id: OTP-10361 Aux Id: kunagi-214 [125]

- TLS 1.2 will now be the default TLS version if sufficient crypto support is available otherwise TLS 1.1 will be default.

  Impact: A default TLS connection will have higher security and hence it may be perceived as slower then before.

  Own Id: OTP-10425 Aux Id: kunagi-275 [186]

- It is now possible to call controlling_process on a listen socket, same as in gen_tcp.

  Own Id: OTP-10447

- Remove filter mechanisms that made error messages backwards compatible with old ssl but hid information about what actually happened.

  This does not break the documented API however other reason terms may be returned, so code that matches on the reason part of {error, Reason} may fail.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-10451 Aux Id: kunagi-270 [181]

- Added missing dependencies to Makefile

  Own Id: OTP-10594

- Removed deprecated function ssl:pid/0, it has been pointless since R14 but has been keep for backwards compatibility.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-10613 Aux Id: kunagi-331 [242]

- Refactor to simplify addition of key exchange methods, thanks to Andreas Schultz.

  Own Id: OTP-10709

### 1.39 SSL 5.1.2

#### Fixed Bugs and Malfunctions

- ssl:ssl_accept/2 timeout is no longer ignored

  Own Id: OTP-10600

### 1.40 SSL 5.1.1

#### Fixed Bugs and Malfunctions

- ssl:recv/3 could "loose" data when the timeout occurs. If the timout in ssl:connect or ssl:ssl_accept expired the ssl connection process was not terminated as it should, this due to gen_fsm:send_all_state_event timout is a client side time out. These timouts are now handled by the gen_fsm-procss instead.

  Own Id: OTP-10569

#### Improvements and New Features

- Better termination handling that avoids hanging.

  Own Id: OTP-10574

### 1.41 SSL 5.1

#### Fixed Bugs and Malfunctions

- Sometimes the client process could receive an extra {error, closed} message after ssl:recv had returned {error, closed}.

  Own Id: OTP-10118

- ssl v3 alert number 41 (no_certificate_RESERVED) is now recognized

  Own Id: OTP-10196

#### Improvements and New Features

- Experimental support for TLS 1.1 is now available, will be officially supported from OTP-R16. Thanks to Andreas Schultz for implementing the first version.

  Own Id: OTP-8871

- Experimental support for TLS 1.2 is now available, will be officially supported from OTP-R16. Thanks to Andreas Schultz for implementing the first version.

  Own Id: OTP-8872

- Removed some bottlenecks increasing the applications parallelism especially for the client side.

  Own Id: OTP-10113

- Workaround for handling certificates that wrongly encode X509countryname in utf-8 when the actual value is a valid ASCCI value of length 2. Such certificates are accepted by many browsers such as Chrome and Fierfox so for interoperability reasons we will too.

  Own Id: OTP-10222

### 1.42 SSL 5.0.1

#### Fixed Bugs and Malfunctions

- Robustness and improvement to distribution over SSL

  Fix a bug where ssl_tls_dist_proxy would crash at caller timeout. Fix a bug where a timeout from the SSL layer would block the distribution indefinately. Run the proxy exclusively on the loopback interface. (Thanks to Paul Guyot)

  Own Id: OTP-9915

- Fix setup loop of SSL TLS dist proxy

  Fix potential leak of processes waiting indefinately for data from closed sockets during socket setup phase. (Thanks to Paul Guyot)

  Own Id: OTP-9916

- Correct spelling of registered (Thanks to Richard Carlsson)

  Own Id: OTP-9925

- Added TLS PRF function to the SSL API for generation of additional key material from a TLS session. (Thanks to Andreas Schultz)

  Own Id: OTP-10024

### 1.43 SSL 5.0

#### Fixed Bugs and Malfunctions

- Invalidation handling of sessions could cause the time_stamp field in the session record to be set to undefined crashing the session clean up process. This did not affect the connections but would result in that the session table would grow.

  Own Id: OTP-9696 Aux Id: seq11947

- Changed code to use ets:foldl and throw instead of ets:next traversal, avoiding the need to explicitly call ets:safe_fixtable. It was possible to get a badarg-crash under special circumstances.

  Own Id: OTP-9703 Aux Id: seq11947

- Send ssl_closed notification to active ssl user when a tcp error occurs.

  Own Id: OTP-9734 Aux Id: seq11946

- If a passive receive was ongoing during a renegotiation the process evaluating ssl:recv could be left hanging for ever.

  Own Id: OTP-9744

#### Improvements and New Features

- Support for the old ssl implementation is dropped and the code is removed.

  Own Id: OTP-7048

- The erlang distribution can now be run over the new ssl implementation. All options can currently not be set but it is enough to replace to old ssl implementation.

  Own Id: OTP-7053

- public_key, ssl and crypto now supports PKCS-8

  Own Id: OTP-9312

- Implements a CBC timing attack counter measure. Thanks to Andreas Schultz for providing the patch.

  Own Id: OTP-9683

- Mitigates an SSL/TLS Computational DoS attack by disallowing the client to renegotiate many times in a row in a short time interval, thanks to Tuncer Ayaz for alerting us about this.

  Own Id: OTP-9739

- Implements the 1/n-1 splitting countermeasure to the Rizzo Duong BEAST attack, affects SSL 3.0 and TLS 1.0. Thanks to Tuncer Ayaz for alerting us about this.

  Own Id: OTP-9750

### 1.44 SSL 4.1.6

#### Fixed Bugs and Malfunctions

- replace "a ssl" with "an ssl" reindent pkix_path_validation/3 Trivial documentation fixes (Thanks to Christian von Roques )

  Own Id: OTP-9464

#### Improvements and New Features

- Adds function clause to avoid denial of service attack. Thanks to Vinod for reporting this vulnerability.

  Own Id: OTP-9364

- Error handling code now takes care of inet:getopts/2 and inets:setopts/2 crashes. Thanks to Richard Jones for reporting this.

  Own Id: OTP-9382

- Support explicit use of packet option httph and httph_bin

  Own Id: OTP-9461

- Decoding of hello extensions could fail to come to the correct conclusion due to an error in a binary match pattern. Thanks to Ben Murphy.

  Own Id: OTP-9589

### 1.45 SSL 4.1.5

#### Improvements and New Features

- Calling gen_tcp:connect with option {ip, {127,0,0,1}} results in an exit with reason badarg. Neither SSL nor INETS This was not catched, resulting in crashes with incomprehensible reasons.

  Own Id: OTP-9289 Aux Id: seq11845

### 1.46 SSL 4.1.3

#### Fixed Bugs and Malfunctions

- Fixed error in cache-handling fix from ssl-4.1.2

  Own Id: OTP-9018 Aux Id: seq11739

- Verification of a critical extended_key_usage-extension corrected

  Own Id: OTP-9029 Aux Id: seq11541

### 1.47 SSL 4.1.2

#### Fixed Bugs and Malfunctions

- The ssl application caches certificate files, it will now invalidate cache entries if the diskfile is changed.

  Own Id: OTP-8965 Aux Id: seq11739

- Now runs the terminate function before returning from the call made by ssl:close/1, as before the caller of ssl:close/1 could get problems with the reuseaddr option.

  Own Id: OTP-8992

### 1.48 SSL 4.1.1

#### Fixed Bugs and Malfunctions

- Correct handling of client certificate verify message When checking the client certificate verify message the server used the wrong algorithm identifier to determine the signing algorithm, causing a function clause error in the public_key application when the key-exchange algorithm and the public key algorithm of the client certificate happen to differ.

  Own Id: OTP-8897

#### Improvements and New Features

- For testing purposes ssl now also support some anonymous cipher suites when explicitly configured to do so.

  Own Id: OTP-8870

- Sends an error alert instead of crashing if a crypto function for the selected cipher suite fails.

  Own Id: OTP-8930 Aux Id: seq11720

### 1.49 SSL 4.1

#### Improvements and New Features

- Updated ssl to ignore CA certs that violate the asn1-spec for a certificate, and updated public key asn1 spec to handle inherited DSS-params.

  Own Id: OTP-7884

- Changed ssl implementation to retain backwards compatibility for old option {verify, 0} that shall be equivalent to {verify, verify_none}, also separate the cases unknown ca and selfsigned peer cert, and restored return value of deprecated function public_key:pem_to_der/1.

  Own Id: OTP-8858

- Changed the verify fun so that it differentiate between the peer certificate and CA certificates by using valid_peer or valid as the second argument to the verify fun. It may not always be trivial or even possible to know when the peer certificate is reached otherwise.

  *** POTENTIAL INCOMPATIBILITY ***

  Own Id: OTP-8873

### 1.50 SSL 4.0.1

#### Fixed Bugs and Malfunctions

- The server now verifies the client certificate verify message correctly, instead of causing a case-clause.

  Own Id: OTP-8721

- The client hello message now always include ALL available cipher suites (or those specified by the ciphers option). Previous implementation would filter them based on the client certificate key usage extension (such filtering only makes sense for the server certificate).

  Own Id: OTP-8772

- Fixed handling of the option {mode, list} that was broken for some packet types for instance line.

  Own Id: OTP-8785

- Empty packets were not delivered to the client.

  Own Id: OTP-8790

- Building in a source tree without prebuilt platform independent build results failed on the SSL examples when:

  - cross building. This has been solved by not building the SSL examples during a cross build.
  - building on Windows.

  Own Id: OTP-8791

- Fixed a handshake error which occurred on some ssl implementations.

  Own Id: OTP-8793

#### Improvements and New Features

- Revise the public_key API - Cleaned up and documented the public_key API to make it useful for general use, also changed ssl to use the new API.

  Own Id: OTP-8722

- Added support for inputing certificates and keys directly in DER format these options will override the pem-file options if specified.

  Own Id: OTP-8723

- To gain interoperability ssl will not check for padding errors when using TLS 1.0. It is first in TLS 1.1 that checking the padding is an requirement.

  Own Id: OTP-8740

- Changed the semantics of the verify_fun option in the ssl-application so that it takes care of both application handling of path validation errors and verification of application specific extensions. This means that it is now possible for the server application in verify_peer mode to handle path validation errors. This change moved some functionality earlier in ssl to the public_key application.

  Own Id: OTP-8770

- Added the functionality so that the verification fun will be called when a certificate is considered valid by the path validation to allow access to each certificate in the path to the user application. Also try to verify subject-AltName, if unable to verify it let the application verify it.

  Own Id: OTP-8825

### 1.51 SSL 4.0

#### Improvements and New Features

- New ssl now support client/server-certificates signed by dsa keys.

  Own Id: OTP-8587

- Ssl has now switched default implementation and removed deprecated certificate handling. All certificate handling is done by the public_key application.

  Own Id: OTP-8695