View Source SSH Release Notes

Ssh 5.2.1

Fixed Bugs and Malfunctions

With this change, race condition between connection closing and automatic window adjustment is fixed.
Own Id: OTP-19109 Aux Id: PR-8345

Ssh 5.2

Fixed Bugs and Malfunctions

SSH processes are now assigned labels for troubleshooting purposes.
Own Id: OTP-19017 Aux Id: PR-8249
With this change, ssh client will automatically adjust transfer window size for commands executed remotely over SSH.
Own Id: OTP-19057 Aux Id: PR-8345, GH-7483

Improvements and New Features

The shell now pages long output from the documentation help command (h(Module)), auto completions and the search command.
Own Id: OTP-18846 Aux Id: PR-7845
The documentation has been migrated to use Markdown and ExDoc.
Own Id: OTP-18955 Aux Id: PR-8026
Updated types and specs for all API modules.
Own Id: OTP-18961

Ssh 5.1.4

Fixed Bugs and Malfunctions

With this change, owner and group file attributes decoding is fixed and results with value of integer type.
Own Id: OTP-19013 Aux Id: GH-7897, PR-8220

Ssh 5.1.3

Fixed Bugs and Malfunctions

With this change, acceptor_sup is not started for ssh client as it is not needed in that role.
Own Id: OTP-18974
With this change, more secure algorithms are preferred by ssh and documentation is updated to reflect that.
Own Id: OTP-18986
With this change, KEX strict terminal message is emitted with debug verbosity.
Own Id: OTP-19002 Aux Id: ERIERL-1041
Fix reading of password for ssh client when in user_interactive mode.
Own Id: OTP-19007 Aux Id: ERIERL-1049

Ssh 5.1.2

Fixed Bugs and Malfunctions

With this change, Curve25519 and Curve448 KEX methods become most preferred (related to RFC8731).
Own Id: OTP-18964

Ssh 5.1.1

Fixed Bugs and Malfunctions

With this change (being response to CVE-2023-48795), ssh can negotiate "strict KEX" OpenSSH extension with peers supporting it; also 'chacha20-poly1305@openssh.com' algorithm becomes a less preferred cipher.
If strict KEX availability cannot be ensured on both connection sides, affected encryption modes(CHACHA and CBC) can be disabled with standard ssh configuration. This will provide protection against vulnerability, but at a cost of affecting interoperability. See Configuring algorithms in SSH.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18897

Ssh 5.1

Fixed Bugs and Malfunctions

Replaced unintentional Erlang Public License 1.1 headers in some files with the intended Apache License 2.0 header.
Own Id: OTP-18815 Aux Id: PR-7780
Avoid outputting ansi escape sequences to dumb ssh clients.
Own Id: OTP-18861 Aux Id: PR-7627
With this change, connection handler does not execute socket operations until it becomes socket owner. Previously errors could occur if connection handler tried to work with socket whose owner exited.
Own Id: OTP-18869 Aux Id: PR-7849,GH-7571

Improvements and New Features

With this change, reverse search works with ssh shell and non dumb terminals.
Own Id: OTP-18730 Aux Id: PR-7499

Ssh 5.0.1

Fixed Bugs and Malfunctions

Added multiline editing support to ssh clients connected through OTP ssh daemon.
Own Id: OTP-18653 Aux Id: PR-7242

Ssh 5.0

Improvements and New Features

The ssh_cli has been updated to work with the changes introduced in the new Erlang shell implementation.
Own Id: OTP-18231 Aux Id: OTP-17932 PR-6144
Typing Ctrl+L in a shell now clears the screen and redraws the current line instead of only redrawing the current line. To only redraw the current line, you must now type Alt+L. This brings the behaviour of Ctrl+L closer to how bash and other shells work.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18285 Aux Id: PR-6262
Deprecates dbg:stop_clear/0 because it is simply a function alias to dbg:stop/0
Own Id: OTP-18478 Aux Id: GH-6903
The implementation has been fixed to use proc_lib:init_fail/2,3 where appropriate, instead of proc_lib:init_ack/1,2.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18490 Aux Id: OTP-18471, GH-6339, PR-6843

Ssh 4.15.3.4

Fixed Bugs and Malfunctions

With this change, owner and group file attributes decoding is fixed and results with value of integer type.
Own Id: OTP-19013 Aux Id: GH-7897, PR-8220

Ssh 4.15.3.3

Fixed Bugs and Malfunctions

With this change, more secure algorithms are preferred by ssh and documentation is updated to reflect that.
Own Id: OTP-18986
With this change, KEX strict terminal message is emitted with debug verbosity.
Own Id: OTP-19002 Aux Id: ERIERL-1041

Ssh 4.15.3.2

Fixed Bugs and Malfunctions

With this change, Curve25519 and Curve448 KEX methods become most preferred (related to RFC8731).
Own Id: OTP-18964

Ssh 4.15.3.1

Fixed Bugs and Malfunctions

With this change, connection handler does not execute socket operations until it becomes socket owner. Previously errors could occur if connection handler tried to work with socket whose owner exited.
Own Id: OTP-18869 Aux Id: PR-7849,GH-7571
With this change (being response to CVE-2023-48795), ssh can negotiate "strict KEX" OpenSSH extension with peers supporting it; also 'chacha20-poly1305@openssh.com' algorithm becomes a less preferred cipher.
If strict KEX availability cannot be ensured on both connection sides, affected encryption modes(CHACHA and CBC) can be disabled with standard ssh configuration. This will provide protection against vulnerability, but at a cost of affecting interoperability. See Configuring algorithms in SSH.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18897

Ssh 4.15.3

Fixed Bugs and Malfunctions

With this change, PKCS8 formatted private key file is properly decoded and SSH daemon with such key can be started.
Own Id: OTP-18446 Aux Id: GH-6475

Improvements and New Features

Replace size/1 with either tuple_size/1 or byte_size/1
The size/1 BIF is not optimized by the JIT, and its use can result in worse types for Dialyzer.
When one knows that the value being tested must be a tuple, tuple_size/1 should always be preferred.
When one knows that the value being tested must be a binary, byte_size/1 should be preferred. However, byte_size/1 also accepts a bitstring (rounding up size to a whole number of bytes), so one must make sure that the call to byte_size/ is preceded by a call to is_binary/1 to ensure that bitstrings are rejected. Note that the compiler removes redundant calls to is_binary/1, so if one is not sure whether previous code had made sure that the argument is a binary, it does not harm to add an is_binary/1 test immediately before the call to byte_size/1.
Own Id: OTP-18432 Aux Id: GH-6672,PR-6793,PR-6784,PR-6787,PR-6785,PR-6682,PR-6800,PR-6797,PR-6798,PR-6799,PR-6796,PR-6813,PR-6671,PR-6673,PR-6684,PR-6694,GH-6677,PR-6696,PR-6670,PR-6674

Ssh 4.15.2

Fixed Bugs and Malfunctions

With this change, ssh application does not crash when formatting some of info reports for unsuccessful connections.
Own Id: OTP-18386 Aux Id: PR-6611
With this change, ssh does not log extensively long messages.
Own Id: OTP-18417 Aux Id: DAFH-1349,ERIERL-888,IA18357

Ssh 4.15.1

Fixed Bugs and Malfunctions

graceful shutdown of ssh_conection_handler when connection is closed by peer
Own Id: OTP-18326 Aux Id: ERIERL-865

Ssh 4.15

Fixed Bugs and Malfunctions

Handling rare race condition at channel close.
Own Id: OTP-18220 Aux Id: ERIERL-666, ERIERL-661

Improvements and New Features

New ssh option no_auth_needed to skip the ssh authentication. Use with caution!
Own Id: OTP-18134 Aux Id: GH-6021
This change fixes dialyzer warnings generated for inets/httpd examples (includes needed adjustment of spec for ssh_sftp module).
Own Id: OTP-18178 Aux Id: ERIERL-833, ERIERL-834, ERIERL-835
The new function ssh:daemon_replace_options/2 makes it possible to change the Options in a running SSH server.
Established connections are not affected, only those created after the call to this new function.
Own Id: OTP-18196
Add a timeout as option max_initial_idle_time. It closes a connection that does not allocate a channel within the timeout time.
For more information about timeouts, see the Timeouts section in the User's Guide Hardening chapter.
Own Id: OTP-18207 Aux Id: PR-6231

Ssh 4.14.1

Fixed Bugs and Malfunctions

Binaries can be limited in logs with the parameter max_log_item_len. The default value is 500 bytes.
Own Id: OTP-18094

Ssh 4.14

Improvements and New Features

The representation of Edward curves (ed25519 and ed448) inside ssh had a temporary representation (ed_pri and ed_pub).
That is now changed to the public_key form. See the manual for more information.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-17920
Former internal function ssh_file:extract_public_key/1 documented publicly.
Internally it was previously in ssh_transport.
Own Id: OTP-18079 Aux Id: GH-5767

Ssh 4.13.2.6

Fixed Bugs and Malfunctions

With this change, more secure algorithms are preferred by ssh and documentation is updated to reflect that.
Own Id: OTP-18986
With this change, KEX strict terminal message is emitted with debug verbosity.
Own Id: OTP-19002 Aux Id: ERIERL-1041
With this change, owner and group file attributes decoding is fixed and results with value of integer type.
Own Id: OTP-19013 Aux Id: GH-7897, PR-8220

Ssh 4.13.2.5

Fixed Bugs and Malfunctions

With this change, Curve25519 and Curve448 KEX methods become most preferred (related to RFC8731).
Own Id: OTP-18964

Ssh 4.13.2.4

Fixed Bugs and Malfunctions

With this change, connection handler does not execute socket operations until it becomes socket owner. Previously errors could occur if connection handler tried to work with socket whose owner exited.
Own Id: OTP-18869 Aux Id: PR-7849,GH-7571
With this change (being response to CVE-2023-48795), ssh can negotiate "strict KEX" OpenSSH extension with peers supporting it; also 'chacha20-poly1305@openssh.com' algorithm becomes a less preferred cipher.
If strict KEX availability cannot be ensured on both connection sides, affected encryption modes(CHACHA and CBC) can be disabled with standard ssh configuration. This will provide protection against vulnerability, but at a cost of affecting interoperability. See Configuring algorithms in SSH.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18897

Ssh 4.13.2.3

Fixed Bugs and Malfunctions

With this change, error logging related crashes in ssh_connection_handler module are fixed.
Own Id: OTP-18620 Aux Id: OTP-18386,PR-6611

Ssh 4.13.2.2

Fixed Bugs and Malfunctions

With this change, ssh application does not crash when formatting some of info reports for unsuccessful connections.
Own Id: OTP-18386 Aux Id: PR-6611
With this change, ssh does not log extensively long messages.
Own Id: OTP-18417 Aux Id: DAFH-1349,ERIERL-888,IA18357

Ssh 4.13.2.1

Fixed Bugs and Malfunctions

Binaries can be limited in logs with the parameter max_log_item_len. The default value is 500 bytes.
Own Id: OTP-18094

Ssh 4.13.2

Fixed Bugs and Malfunctions

Fix makefile dependency bugs.
Own Id: OTP-17847 Aux Id: PR-5574 GH-5548
Fixed faulty OpenSSH decoding of Ed25519/Ed448 keys in the OpenSSH format openssh_key_v1.
Own Id: OTP-17868 Aux Id: PR-5520
Correction of ssh_file typing, specially for the experimental openssh-key-v1 encoding.
Own Id: OTP-17912 Aux Id: GH-5680
Improper tag for private ED keys when encoding with ssh:encode/2.
The tuple had ed_priv as first element, but should have had ed_pri. This is now corrected.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-17928 Aux Id: PR-5679

Improvements and New Features

Add support for Ed25519/Ed448 SSH host keys in the RFC 4716 format ("-----BEGIN EC PRIVATE KEY-----") generated by for example openssl or via Erlang functions (i.e. public_key:generate_key({namedCurve, ed25519})).
Ed25519 SSH host keys generated by ssh-keygen was, and are still, supported.
Own Id: OTP-17857 Aux Id: PR-5532

Ssh 4.13.1

Fixed Bugs and Malfunctions

The ssh sever parallel_login option was missing in OTP-24
Own Id: OTP-17850 Aux Id: ERIERL-764

Ssh 4.13

Fixed Bugs and Malfunctions

The value of the connect_timeout option is now used as default value for the negotiation timeout.
Own Id: OTP-17707 Aux Id: ERIERL-706

Improvements and New Features

Add better error handling in connect/2,3,4. Detect incorrect arguments and return an informative error tuple instead of throwing a function_clause or similar.
Own Id: OTP-17515 Aux Id: ERIERL-648
Make ssh algorithm selection better handle dynamic changes changes in crypto fips mode.
Own Id: OTP-17795

Ssh 4.12.5

Fixed Bugs and Malfunctions

Fixed a race condition in the acceptor loop: if a client disconnected immediately after the tcp connect, the server could cease handling connection on that address:port.
Own Id: OTP-17764 Aux Id: ERIERL-726

Ssh 4.12.4

Fixed Bugs and Malfunctions

Fixed that a slow start (>30s) of a client subsystem could cause a log entry with the password.
Own Id: OTP-17390 Aux Id: ERIERL-648
Fixed an error when running as an sftp server and a client requests a directory contents listing.
The fix is to handle the error code {error, eacces} as {error, enoent} in the ssh_sftpd:get_attrs/5 internal function; that is, just skip it.
Own Id: OTP-17586 Aux Id: GH-5014

Improvements and New Features

The "Key exchange failed" Info Report is now more informative.
Own Id: OTP-17450 Aux Id: ERIERL-655

Ssh 4.12.3

Fixed Bugs and Malfunctions

Filter out sensitive data (passwords etc) from progress reports and supervisor reports.
Own Id: OTP-17468 Aux Id: ERIERL-656

Ssh 4.12.2

Fixed Bugs and Malfunctions

Avoid an extra blank line in the ssh known_hosts file
Own Id: OTP-17427

Ssh 4.12.1

Improvements and New Features

Add missing known_hosts and authorized_keys file types to ssh_file:decode/2 and ssh_file:encode/2.
Own Id: OTP-17397

Ssh 4.12

Fixed Bugs and Malfunctions

Missing runtime dependencies has been added to this application.
Own Id: OTP-17243 Aux Id: PR-4557
The send window handling is changed to not initialize a too large window on some occasions.
Own Id: OTP-17353

Improvements and New Features

Removed usage of erlang:is_port/1 from the SSH implementation.
Own Id: OTP-16750
Internal connection setup refactoring.
Own Id: OTP-17051
Refactor SSH fsm into a (hopefully) more comprehensible set of gen_statem callback-files.
Own Id: OTP-17140
The RSA SHA1 sign/verify variants are disabled by default. That is, ssh-rsa is disabled by default as well as the SHA1 sign/verify with RSA keys from id_rsa and ssh_host_rsa_key. All SHA2 sign/verify are enabled by default.
The reason is that SHA1 is now considered easy to break.
To enable RSA with SHA1, for example for a very old and unsafe peer, see Example 9 in the User's Guide chapter Configuring algorithms in SSH.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-17259 Aux Id: OTP-16511, ERIERL-619
Adapt ssh supervisors to the new 'significant' and 'auto_shutdown' flags in supervisor.
Own Id: OTP-17322 Aux Id: PR-4638, EEP-56, OTP-17334
The functions public_key:ssh_encode/2, public_key:ssh_decode/2, public_key:ssh_hostkey_fingerprint/1 and public_key:ssh_hostkey_fingerprint/2 are deprecated.
Replacement functions are available in SSH, see the Deprecations chapter in the Erlang/OTP documentation.
Own Id: OTP-17352

Ssh 4.11.1.7

Fixed Bugs and Malfunctions

With this change (being response to CVE-2023-48795), ssh can negotiate "strict KEX" OpenSSH extension with peers supporting it; also 'chacha20-poly1305@openssh.com' algorithm becomes a less preferred cipher.
If strict KEX availability cannot be ensured on both connection sides, affected encryption modes(CHACHA and CBC) can be disabled with standard ssh configuration. This will provide protection against vulnerability, but at a cost of affecting interoperability. See Configuring algorithms in SSH User's Guide.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18897
With this change, KEX strict terminal message is emitted with debug verbosity.
Own Id: OTP-19002 Aux Id: ERIERL-1041

Ssh 4.11.1.6

Fixed Bugs and Malfunctions

Binaries can be limited in logs with the parameter max_log_item_len. The default value is 500 bytes.
Own Id: OTP-18094

Ssh 4.11.1.5

Fixed Bugs and Malfunctions

Fixed problem with blocked server after multiple restarts. Applies to daemons with options {parallel_login,true} and also {max_sessions, int()>0}.
Own Id: OTP-17835 Aux Id: ERIERL-721

Ssh 4.11.1.4

Fixed Bugs and Malfunctions

The value of the connect_timeout option is now used as default value for the negotiation timeout.
Own Id: OTP-17707 Aux Id: ERIERL-706

Ssh 4.11.1.3

Fixed Bugs and Malfunctions

Filter out sensitive data (passwords etc) from progress reports and supervisor reports.
Own Id: OTP-17468 Aux Id: ERIERL-656

Improvements and New Features

The "Key exchange failed" Info Report is now more informative.
Own Id: OTP-17450 Aux Id: ERIERL-655

Ssh 4.11.1.2

Fixed Bugs and Malfunctions

Avoid an extra blank line in the ssh known_hosts file
Own Id: OTP-17427

Ssh 4.11.1.1

Fixed Bugs and Malfunctions

Fixed that a slow start (>30s) of a client subsystem could cause a log entry with the password.
Own Id: OTP-17390 Aux Id: ERIERL-648

Ssh 4.11.1

Fixed Bugs and Malfunctions

The idle_time timer was not cancelled when a channel was opened within the timeout time on an empty connection that have had channels previously.
Own Id: OTP-17279

Ssh 4.11

Improvements and New Features

The long name field in SSH_FXP_NAME responses to display file information in sftp version 3 now contains the expanded format defined in the sftp draft. It is similar to what is returned by "ls -l" on Unix systems.
Own Id: OTP-17197 Aux Id: PR- 3049

Ssh 4.10.8

Fixed Bugs and Malfunctions

Don't timeout slow connection setups and tear-downs. A rare crash risk for the controller is also removed.
Own Id: OTP-17173 Aux Id: ERIERL-581

Ssh 4.10.7

Fixed Bugs and Malfunctions

The SSH daemon erroneously replaced LF with CRLF also when there was no pty requested from the server.
Own Id: OTP-17108 Aux Id: ERL-1442

Ssh 4.10.6

Fixed Bugs and Malfunctions

Fixed problems in the ssh cli/shell handling. Most important are:
1. the ssh:shell function did sometimes cause the input to be echoed twice,
2. the ssh:shell function didn't transfer the LANG and LC_ALL shell variables to the connected server which sometimes made Unicode handling erroneous,
3. Unicode was not always transferred correctly to and from the peer.
Own Id: OTP-16799
The SSH protocol message SSH_MSG_DISCONNECT was sometimes sent instead of SSH_MSG_CHANNEL_FAILURE
Own Id: OTP-16900
The ssh_cli module now always sends the exit-status to connected clients so they can use that to check for successful command execution.
Own Id: OTP-16908 Aux Id: PR-2753

Improvements and New Features

A new option pk_check_user enables checking of the client's user name in the server when doing public key authentication.
Own Id: OTP-16889

Ssh 4.10.5

Fixed Bugs and Malfunctions

An ssh-client can take an accepted socket from a listening socket and do an ssh:connect/2 on it.
Multiple clients on sockets accepted from the same listening socket had stopped working. This is corrected now.
Own Id: OTP-17021 Aux Id: ERIERL-567

Ssh 4.10.4.1

Fixed Bugs and Malfunctions

Filter out sensitive data (passwords etc) from progress reports and supervisor reports.
Own Id: OTP-17468 Aux Id: ERIERL-656

Ssh 4.10.4

Fixed Bugs and Malfunctions

The inet option raw was not passed on from the ssh option list to inet.
Own Id: OTP-17016 Aux Id: ERIERL-562

Ssh 4.10.3

Fixed Bugs and Malfunctions

A supervisor sub-tree could be left if the connection handler process is brutally killed. This will make the max_sessions checking option to count the existing sessions erroneously and could finally block further sessions.
Own Id: OTP-17006 Aux Id: ERIERL-556

Ssh 4.10.2

Fixed Bugs and Malfunctions

Fix decoder bug.
Own Id: OTP-16904

Ssh 4.10.1

Fixed Bugs and Malfunctions

Fixed a bug when a message to ssh-agent was divided into separate packets.
Own Id: OTP-16761 Aux Id: PR-2679
Fix a bug that could crash the cli server if a too large cli-window was requested from the client.
Own Id: OTP-16791 Aux Id: ERIERL-520

Improvements and New Features

Increased test coverage.
Own Id: OTP-14106
A chapter about hardening the OTP SSH is added to the User's Guide.
Own Id: OTP-16411
The internal Diffie-Hellman high level API for key generation was slow in old and by OpenSSL now unsupported cryptolib versions (1.0.1 and earlier).
If such a cryptolib is used anyhow, the low-level API is used internally in the crypto application.
Own Id: OTP-16774
A new timeout is defined for daemons: hello_timeout.
The timeout is supposed to be used as a simple DoS attack protection. It closes an incoming TCP-connection if no valid first SSH message is received from the client within the timeout limit after the TCP initial connection setup.
The initial value is 30s by compatibility reasons, but could be lowered if needed, for example in the code or in a config file.
Own Id: OTP-16803

Ssh 4.10

Fixed Bugs and Malfunctions

Fix error in ssh_sftpd typespec.
Own Id: OTP-16363

Improvements and New Features

The plug-in file ssh_file.erl, that is responsible for default file handling, is re-factored, optimized and re-written.
Own Id: OTP-11688 Aux Id: OTP-12699
OpenSSH 6.5 introduced a new file representation of keys called openssh-key-v1.
OTP/SSH had an experimental implementation of this format. That implementation is now improved and supported with the exception of handling encrypted keys.
Own Id: OTP-15434
TCP/IP port forwarding, a.k.a tunneling a.k.a tcp-forward/direct-tcp is implemented. In the OpenSSH client, this corresponds to the options -L and -R.
The client or server listens to a specified socket, and when something connects to it with TCP/IP, that connection is forwarded in an encrypted tunnel to the peer. The peer then connects to a predefined IP/port pair and then acts as a proxy.
See the manual, ssh:tcpip_tunnel_to_server/6 and ssh:tcpip_tunnel_from_server/6.
The functionality is disabled per default but can be enabled when starting a daemon.
Own Id: OTP-15998 Aux Id: PR-2376, PR-2368
The client-side of the supervisor tree (under sshc_sup) was previously not complete; the channel handling processes were handled with links but had no supervisors.
This is now corrected with a client-side supervisor tree under sshc_sup, similar to the server-side supervisor tree under sshd_sup.
Own Id: OTP-16026 Aux Id: PR-2368, (OTP-15998)
The extension posix-rename@openssh.com is added to the ssh/sftp rename operation.
Own Id: OTP-16289 Aux Id: PR-2448
Calls of deprecated functions in the Old Crypto API are replaced by calls of their substitutions.
Own Id: OTP-16346
The default known_hosts file handling is improved to include ports.
The handling of the contents in that file is updated to support the full syntax, with exception of 1) the wildcard '?', 2) wildcards in canonical names and 3) the option '@cert-authority'
Own Id: OTP-16506
The MAC (Message Authorization Code) algorithms
- hmac-sha1-etm@openssh.com
- hmac-sha2-256-etm@openssh.com
- hmac-sha2-512-etm@openssh.com
are implemented.
Own Id: OTP-16508
The key-exchange algorithms 'diffie-hellman-group14-sha1' and 'diffie-hellman-group-exchange-sha1' are disabled per default. The reason is that SHA1 now is considered insecure.
They can be enabled if needed, see SSH (App).
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-16509
The public key algorithm 'ssh-dss' is disabled per default. The reason is that it is now considered as insecure.
It can be enabled if needed, see SSH (App).
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-16510
The public key 'ssh-rsa' is now considered as insecure because of its usage of SHA1.
It is therefore deprecated and will no longer be enabled per default in OTP-24.0.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-16511
An option optimize (optimize_key_lookup) is introduced for the file interface ssh_file.erl
The option enables the user to select between the default handling which is fast but memory consuming vs memory efficient but not as fast. The effect might be observable only for large files.
See the manual for ssh_file:is_host_key/5 and ssh_file:is_auth_key/3.
Own Id: OTP-16512
The ssh agent is now implemented in the ssh_agent key callback module.
Enable with the the option {key_cb, {ssh_agent, []}} in for example ssh:connect/3.
See the ssh_agent manual for details.
Own Id: OTP-16513
Algorithm configuration could now be done in a .config file.
This is useful for example to enable an algorithm that is disabled by default. It could now be enabled in an .config-file without changing the code,
See the SSH User's Guide chapter "Configuration in SSH".
Own Id: OTP-16540
Documented which gen_tcp socket options can't be used in calls to ssh:connect and ssh:daemon.
Own Id: OTP-16589
Added kb_int_fun_4() to the authentication_daemon_options() to enable generating dynamic keyboard-interactive prompts from the user's state returned from the authentication fun pwdfun_4().
Own Id: OTP-16622 Aux Id: PR-2604

Ssh 4.9.1.5

Fixed Bugs and Malfunctions

With this change (being response to CVE-2023-48795), ssh can negotiate "strict KEX" OpenSSH extension with peers supporting it; also 'chacha20-poly1305@openssh.com' algorithm becomes a less preferred cipher.
If strict KEX availability cannot be ensured on both connection sides, affected encryption modes(CHACHA and CBC) can be disabled with standard ssh configuration. This will provide protection against vulnerability, but at a cost of affecting interoperability. See Configuring algorithms in SSH User's Guide.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-18897
With this change, KEX strict terminal message is emitted with debug verbosity.
Own Id: OTP-19002 Aux Id: ERIERL-1041

Ssh 4.9.1.4

Fixed Bugs and Malfunctions

The value of the connect_timeout option is now used as default value for the negotiation timeout.
Own Id: OTP-17707 Aux Id: ERIERL-706

Ssh 4.9.1.3

Fixed Bugs and Malfunctions

The idle_time timer was not cancelled when a channel was opened within the timeout time on an empty connection that have had channels previously.
Own Id: OTP-17279

Ssh 4.9.1.2

Fixed Bugs and Malfunctions

Fix decoder bug.
Own Id: OTP-16904

Ssh 4.9.1.1

Fixed Bugs and Malfunctions

Fix a bug that could crash the cli server if a too large cli-window was requested from the client.
Own Id: OTP-16791 Aux Id: ERIERL-520

Improvements and New Features

A new timeout is defined for daemons: hello_timeout.
It closes an incoming TCP-connection if no valid 1st message is received from the client within the timeout limit.
Own Id: OTP-16803

Ssh 4.9.1

Fixed Bugs and Malfunctions

Potential hazard between re-keying decision and socket close.
Own Id: OTP-16462 Aux Id: ERIERL-464

Ssh 4.9

Fixed Bugs and Malfunctions

Unicode problems for ssh_sftp:write fixed.
Own Id: OTP-16377

Improvements and New Features

Changes to the internal api of the experimental ssh_dbg tool.
Own Id: OTP-16353
The new functions ssh:set_sock_opts/2 and ssh:get_sock_opts/2 sets and reads option values for the underlying TCP stream.
Own Id: OTP-16485

Ssh 4.8.2

Fixed Bugs and Malfunctions

Fixed that ssh_connection:send could allocate a large amount of memory if given an iolist() as input data.
Own Id: OTP-16373
Safe atom conversions.
Own Id: OTP-16375
Constant time comparisons added.
Own Id: OTP-16376

Ssh 4.8.1

Fixed Bugs and Malfunctions

The ssh cli (e.g shell) server behaved strangely when characters were inserted in a string such that the last characters tried to wrap the line.
Own Id: OTP-14849 Aux Id: ERL-545
If an OTP SSH server was serving an "exec" request and the executed code used Erlang standard_io for input/output, the I/O was erroneously handled by the server's group leader, so the I/O turned up in the the server's Erlang shell (if any). The user at the client side did therefore not see that I/O.
This is corrected now, so the client - for example the ssh OS shell command - handles the I/O. The user could send input to the server side exec handling code by writing on the terminal, and server side output from for example io:format is presented on the terminal - not only the functional result.
NOTE 1: Servers executing exec requests with the old, undocumented ways of specifying the custom exec handler is not changed. Changed are only the two cases where the server's 'exec' option either:
1. is not specified (i.e. using the default shell) or,
2. it has the {direct, fun(...) -> ... end} value format.
NOTE 2: Previously an end-of-line marker was appended on the result and error reports at the client side. They are removed now and the error reports are slightly enhanced.
TECHNICAL DETAILS: The server's device standard_input receives data events from the exec request's channel, and the device standard_output is sending its data by data events to the client on that channel. The result is that standard_io is now performed by the client's group leader.
Own Id: OTP-15417 Aux Id: OTP-16108
The functions ssh:shell/1,2,3 left the connection open when they returned. That leakage is fixed now.
Own Id: OTP-16047
Corrected that an Erlang SSH server could return the status code 4294967295 instead of 255 on some errors of an exec request.
Own Id: OTP-16123

Improvements and New Features

Internal simplification of ssh_sftp/ssh_xfer
Own Id: OTP-15972
The documentation of One-Time Execution in the User's Guide is updated with more examples.
Own Id: OTP-16108 Aux Id: OTP-15417
The new value 'disabled' is introduced in the SSH daemon options 'exec' and 'shell'. Previously they lacked a clear way of disabling them.
Own Id: OTP-16113
The old algorithms 'aes192_cbc', 'aes256_cbc' and 'hmac-sha1-96' are added for compatibility with older peers.
The mac 'hmac-sha1-96' is nowadays not recommended and must therefore be explicitly enabled. Use for example the Option value {modify_algorithms, [{append, [{mac,['hmac-sha1-96']}]}]}
Own Id: OTP-16170

Ssh 4.8

Fixed Bugs and Malfunctions

Fixed wrong type definition for the daemon option subsystems.
Own Id: OTP-15820
Fixed a possible SSH logging crash if there was a problem in an early stage of session setup.
Own Id: OTP-15962 Aux Id: ERL-990

Improvements and New Features

The documentation for the modules ssh_connection, ssh_sftp and ssh_sftpd are now generated from the -spec:s.
Own Id: OTP-15395
Internal cleanup including removal of the internal file ssh_userauth.hrl.
Own Id: OTP-15876 Aux Id: PR-2255, PR-2256
Removed unused definitions in ssh.hrl.
Own Id: OTP-15929 Aux Id: PR-2297
Removed unused fields in the internal #connection{} record.
Own Id: OTP-15984
To get information of a connection_ref() from for example ssh:connect/3, there was previously one function available namely ssh:connection_info/2. This ticket adds ssh:connection_info/1 which returns all information.
For daemons (servers) started with for example ssh:daemon/2 the function ssh:daemon_info/1 returning all information was available. This ticket adds ssh:daemon_info/2 which returns only the information specified in the second argument.
The info of connections and of daemons now also includes the item 'options'. Only those options that does not have their default values are returned.
For a connection also the items 'algorithms' and 'channels' are added.
Own Id: OTP-16040

Ssh 4.7.7

Improvements and New Features

SSH uses the new crypto API.
Own Id: OTP-15673

Ssh 4.7.6.6

Fixed Bugs and Malfunctions

The idle_time timer was not cancelled when a channel was opened within the timeout time on an empty connection that have had channels previously.
Own Id: OTP-17279

Ssh 4.7.6.5

Fixed Bugs and Malfunctions

Fix decoder bug.
Own Id: OTP-16904

Ssh 4.7.6.4

Fixed Bugs and Malfunctions

Potential hazard between re-keying decision and socket close.
Own Id: OTP-16462 Aux Id: ERIERL-464

Ssh 4.7.6.3

Fixed Bugs and Malfunctions

Fixed that ssh_connection:send could allocate a large amount of memory if given an iolist() as input data.
Own Id: OTP-16373
Safe atom conversions.
Own Id: OTP-16375
Constant time comparisons added.
Own Id: OTP-16376

Ssh 4.7.6.2

Fixed Bugs and Malfunctions

The ssh cli (e.g shell) server behaved strangely when characters were inserted in a string so that the last characters tried to wrap the line.
Own Id: OTP-14849 Aux Id: ERL-545

Ssh 4.7.6.1

Fixed Bugs and Malfunctions

Fixed a possible SSH logging crash if there was a problem in an early stage of session setup.
Own Id: OTP-15962 Aux Id: ERL-990

Ssh 4.7.6

Improvements and New Features

When an SSH server receives the very first message on a new TCP connection, and that message is not the expected one, the 64 first bytes of the received message are now dumped in the INFO REPORT that reports the Protocol Error.
This facilitates the debugging of who sends the bad message or of detecting a possible port scanning.
Own Id: OTP-15772

Ssh 4.7.5

Fixed Bugs and Malfunctions

The callback ssh_channel:init/1 was missing in OTP-21
Own Id: OTP-15762
If a client was connected to an server on an already open socket, the callback fun(PeerName,FingerPrint) in the accept_callback option passed the local name in the argument PeerName instead of the remote name.
Own Id: OTP-15763

Ssh 4.7.4

Fixed Bugs and Malfunctions

SSH sftp daemon now accepts an SSH_FXP_STAT message encoded according to the wrong sftp version. Some clients sends such messages.
Own Id: OTP-15498 Aux Id: ERL-822, PR-2077

Ssh 4.7.3

Fixed Bugs and Malfunctions

Fixed port leakage if a ssh:daemon call failed.
Own Id: OTP-15397 Aux Id: ERL-801

Ssh 4.7.2

Fixed Bugs and Malfunctions

Incompatibility with newer OpenSSH fixed. Previously versions 7.8 and later could cause Erlang SSH to exit.
Own Id: OTP-15413
The 'exec' option for ssh daemons had wrong format in the documentation.
Own Id: OTP-15416

Improvements and New Features

Added public key methods ssh-ed25519 and ssh-ed448.
Requires OpenSSL 1.1.1 or higher as cryptolib under the OTP application crypto.
Own Id: OTP-15094 Aux Id: OTP-15419
The SSH property tests are now adapted to the PropEr testing tool.
Own Id: OTP-15312
The term "user" was not documented in the SSH app. A new chapter with terminology is added to the User's Manual where the term "user" is defined.
A reference manual page about the module ssh_file is also added. This is the default callback module for user's keys, host keys etc.
Own Id: OTP-15314
Host and user key checking is made more robust.
Own Id: OTP-15424

Ssh 4.7.1

Improvements and New Features

Extended the undocumented ssh_dbg debug module with an api for a circular trace buffer. This makes it easy to record the last low-level events before an error is detected. It is intended for solving difficult errors.
Own Id: OTP-15020
The key exchange methods 'curve25519-sha256@libssh.org', 'curve25519-sha256' and 'curve448-sha512' are implemented. The last two are defined in https://tools.ietf.org/html/draft-ietf-curdle-ssh-curves
They all depends on that OpenSSL 1.1.1 or higher is used as cryptolib.
Own Id: OTP-15133 Aux Id: OTP-15240
The cipher 'chacha20-poly1305@openssh.com' is now supported if OpenSSL 1.1.1 or higher is used as cryptolib.
Own Id: OTP-15209 Aux Id: OTP-15164

Ssh 4.7

Fixed Bugs and Malfunctions

If the daemon port listener is restarted, it could potentially fail with eaddrinuse if the timing is unlucky. It will now retry and exponentially back off the listener restart a few times before failing.
Own Id: OTP-14955
A channel callback module always got the module name as reason in a call to terminate. Now it will get the proper Reason, usually 'normal'.
Own Id: OTP-15084

Improvements and New Features

The option exec has new option values defined to make it much more easy to implement an own exec server.
An option called exec for daemons implementing the handling of 'exec' requests has existed a long time but has been undocumented. The old undocumented value - as well as its behavior - is kept for compatibility EXCEPT that error messages are changed and are sent as "stderror" text.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-14851
Updated ssh_connection:shell/2 documentation.
Own Id: OTP-14880
The experimental ssh_dbg module is completely re-written. Its purpose is to make tracing and debugging easier on deployed systems.
Own Id: OTP-14896
The SSH supervisor structure has been slightly changed. This makes stopping the ssh application considerably faster if there are open connections. This is important in for example restarts.
Own Id: OTP-14988
The type specifications in SSH are completely reworked and the following types are renamed:
ssh:ssh_connection_ref() is changed to ssh:connection_ref(),
ssh:ssh_daemon_ref() is changed to ssh:daemon_ref(),
ssh:ssh_channel_id() is changed to ssh:channel_id().
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-15002 Aux Id: OTP-15030
The internal timer handling in SSH is now based on the gen_statem timers.
Own Id: OTP-15019
Removed the undocumented and unused modules ssh_client_key.erl and ssh_server_key.erl.
Own Id: OTP-15028
The Reference Manual pages are partly updated.
The ssh page is now generated from specs and types, is restructured and is partly rephrased.
The ssh_channel, ssh_connection, ssh_client_key_api, ssh_server_key_api and ssh_sftp pages are updated with links, correct type names and some minor changes.
Own Id: OTP-15030 Aux Id: OTP-15002
The behaviors ssh_channel and ssh_daemon_channel are renamed to ssh_client_channel and ssh_server_channel respectively.
The old modules are kept for compatibility but should preferably be replaced when updating callback modules referring them.
Own Id: OTP-15041
New test suite for channels.
Own Id: OTP-15051
The rekey_limit option could now set the max time as well as the previously max data amount.
Own Id: OTP-15069 Aux Id: ERL-617
Changed process exit supervision from links to monitors.
Own Id: OTP-15082
Better handling of misbehaving channel callback modules.
Own Id: OTP-15083
A new moduli file is generated. This file is used for the recommended diffie-hellman-group-exchange-sha256 key exchange algorithm in SSH.
Own Id: OTP-15113

Ssh 4.6.9.7

Fixed Bugs and Malfunctions

Fixed possible hanging in ssh_sftp:stop_channel/1.
Own Id: OTP-16507 Aux Id: ERIERL-470

Ssh 4.6.9.6

Fixed Bugs and Malfunctions

Fixed that ssh_connection:send could allocate a large amount of memory if given an iolist() as input data.
Own Id: OTP-16373
Safe atom conversions.
Own Id: OTP-16375
Constant time comparisons added.
Own Id: OTP-16376

Ssh 4.6.9.5

Fixed Bugs and Malfunctions

The ssh cli (e.g shell) server behaved strangely when characters were inserted in a string so that the last characters tried to wrap the line.
Own Id: OTP-14849 Aux Id: ERL-545

Ssh 4.6.9.4

Fixed Bugs and Malfunctions

If a client was connected to an server on an already open socket, the callback fun(PeerName,FingerPrint) in the accept_callback option passed the local name in the argument PeerName instead of the remote name.
Own Id: OTP-15763

Ssh 4.6.9.3

Fixed Bugs and Malfunctions

Fixed port leakage if a ssh:daemon call failed.
Own Id: OTP-15397 Aux Id: ERL-801

Ssh 4.6.9.2

Fixed Bugs and Malfunctions

Incompatibility with newer OpenSSH fixed. Previously versions 7.8 and later could cause Erlang SSH to exit.
Own Id: OTP-15413

Ssh 4.6.9.1

Fixed Bugs and Malfunctions

SFTP clients reported the error reason "" if a non-OTP sftp server was killed during a long file transmission.
Now the signal name (for example "KILL") will be the error reason if the server's reason is empty.
The documentation also lacked type information about this class of errors.
Own Id: OTP-15148 Aux Id: ERIERL-194
Fix ssh_sftp decode error for sftp protocol version 4
Own Id: OTP-15149 Aux Id: ERIERL-199

Ssh 4.6.9

Fixed Bugs and Malfunctions

Host key hash erroneously calculated for clients following draft-00 of RFC 4419, for example PuTTY
Own Id: OTP-15064
Renegotiation could fail in some states
Own Id: OTP-15066

Ssh 4.6.8

Fixed Bugs and Malfunctions

An ssh_sftp server (running version 6) could fail if it is told to remove a file which in fact is a directory.
Own Id: OTP-15004
Fix rare spurious shutdowns of ssh servers when receiving {'EXIT',_,normal} messages.
Own Id: OTP-15018

Ssh 4.6.7

Fixed Bugs and Malfunctions

Fix bad spec in ssh.hrl: double_algs().
Own Id: OTP-14990

Ssh 4.6.6

Fixed Bugs and Malfunctions

Remove a blocking risk when a channel is closed and an operation is tried on that channel after at least a second's time gap.
Own Id: OTP-14939

Improvements and New Features

Added ssh_compat_SUITE.
This suite contains a number of interoperability tests mainly with OpenSSH. The tests start docker containers with different OpenSSH and OpenSSL/LibreSSLcryptolib versions and performs a number of tests of supported algorithms.
All login methods and all user's public key types are tested both for the client and the server.
All algorithms for kex, cipher, host key, mac and compressions are tested with a number of exec and sftp tests, both for the client and the server.
Own Id: OTP-14194 Aux Id: OTP-12487
Default exec is disabled when a user-defined shell is enabled.
Own Id: OTP-14881

Ssh 4.6.5

Fixed Bugs and Malfunctions

Adjusted supervisor timeouts
Own Id: OTP-14907
Remove ERROR messages for slow process exits
Own Id: OTP-14930

Improvements and New Features

Add option save_accepted_host to ssh:connection. This option, if set to false, inhibits saving host keys to e.g the file known_hosts.
Own Id: OTP-14935

Ssh 4.6.4

Fixed Bugs and Malfunctions

Fix problem with OpenSSH 7.2 (and later) clients that has used sha1 instead of sha2 for rsa-sha-256/512 user's public keys.
Own Id: OTP-14827 Aux Id: ERL-531

Ssh 4.6.3

Fixed Bugs and Malfunctions

Passphrase option for ecdsa public keys was missing.
Own Id: OTP-14602

Improvements and New Features

The host and user public key handling is hardened so that a faulty plugin can't deliver a key of wrong type.
Better checks in the server of the available hostkey's types at start and at each accept.
Better checks in the client of the available user public key types at connect.
Own Id: OTP-14676 Aux Id: ERIERL-52, OTP-14570
SSH can now fetch the host key from the private keys stored in an Engine. See the crypto application for details about Engines.
Own Id: OTP-14757

Ssh 4.6.2

Fixed Bugs and Malfunctions

Trailing white space was removed at end of the hello-string. This caused interoperability problems with some other ssh-implementations (e.g OpenSSH 7.3p1 on Solaris 11)
Own Id: OTP-14763 Aux Id: ERIERL-74
Fixes that tcp connections that was immediately closed (SYN, SYNACK, ACK, RST) by a client could be left in a zombie state.
Own Id: OTP-14778 Aux Id: ERIERL-104

Ssh 4.6.1

Fixed Bugs and Malfunctions

Fixed broken printout
Own Id: OTP-14645

Improvements and New Features

Disable aes_gcm ciphers if peer is OpenSSH 6.2 which is known to have trouble with them in some cases.
Own Id: OTP-14638

Ssh 4.6

Fixed Bugs and Malfunctions

Enables the ssh_io module to also accept binary values when reading standard_io instead of getting stuck in the receive clause.
Own Id: OTP-14506 Aux Id: PR1503
Previously, the file owner access permission in response to ssh_sftp:read_file_info/2 function was always read_write. With this fix, the actual value of file owner access permission is added to the returning record. That value is calculated from file mode value.
Own Id: OTP-14550 Aux Id: PR1533

Improvements and New Features

A new option modify_algorithms is implemented. It enables specifying changes on the default algorithms list. See the reference manual and the SSH User's Guide chapter "Configuring algorithms in SSH".
Own Id: OTP-14568

Ssh 4.5.1

Fixed Bugs and Malfunctions

All unknown options are sent to the transport handler regardless of type.
Own Id: OTP-14541 Aux Id: EIRERL-63

Ssh 4.5

Improvements and New Features

The internal handling of SSH options is re-written.
Previously there were no checks if a client option was given to a daemon or vice versa. This is corrected now. If your code has e.g. a client-only option in a call to start a daemon, the call will fail.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-12872
Modernization of key exchange algorithms. See draft-ietf-curdle-ssh-kex-sha2 for a discussion.
Removed an outdated weak algorithm and added stronger replacements to keep interoperability with other modern ssh clients and servers. The default ordering of the algorithms is also adjusted.
Retired: The nowadays unsecure key-exchange diffie-hellman-group1-sha1 is not enabled by default, but can be enabled with the option preferred-algorithms.
Added: The new stronger key-exchange diffie-hellman-group16-sha512, diffie-hellman-group18-sha512 and diffie-hellman-group14-sha256 are added and enabled by default.
The questionable [RFC 6194] sha1-based algorithms diffie-hellman-group-exchange-sha1 and diffie-hellman-group14-sha1 are however still kept enabled by default for compatibility with ancient clients and servers that lack modern key-exchange alternatives. When the draft-ietf-curdle-ssh-kex-sha2 becomes an rfc, those sha1-based algorithms and diffie-hellman-group1-sha1 will be deprecated by IETF. They might then be removed from the default list in Erlang/OTP.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-14110
Modernized internal representation of sftp by use of maps.
Own Id: OTP-14117
The Extension Negotiation Mechanism and the extension server-sig-algs in draft-ietf-curdle-ssh-ext-info-05 are implemented.
The related draft-ietf-curdle-rsa-sha2-05 is implemented and introduces the signature algorithms rsa-sha2-256 and rsa-sha2-512.
Own Id: OTP-14193
The 'timeout' and 'connect_timeout' handling in ssh_sftp:start_channel documentation is clarified.
Own Id: OTP-14216
The functions ssh:connect, ssh:shell and ssh:start_channel now accept an IP-tuple as Host destination argument.
Own Id: OTP-14243
The function ssh:daemon_info/1 now returns Host and Profile as well as the Port info in the property list.
Own Id: OTP-14259
Removed the option public_key_alg which was deprecated in 18.2. Use pref_public_key_algs instead.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-14263
The SSH application is refactored regarding daemon starting. The resolution of contradicting Host argument and ip option were not described. There were also strange corner cases when the 'any' value was used in Host argument or ip option. This is (hopefully) resolved now, but it may cause incompatibilities for code using both Host and the ip option. The value 'loopback' has been added for a correct way of naming those addresses.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-14264
The supervisor code is refactored. The naming of listening IP-Port-Profile triples are slightly changed to improve consistency in strange corner cases as resolved by OTP-14264
Own Id: OTP-14267 Aux Id: OTP-14266
The idle_time option can now be used in daemons.
Own Id: OTP-14312
Added test cases for IETF-CURDLE Extension Negotiation (ext-info)
Own Id: OTP-14361
Testcases for IETF-CURDLE extension server-sig-algs including rsa-sha2-*
Own Id: OTP-14362 Aux Id: OTP-14361
The option auth_methods can now also be used in clients to select which authentication options that are used and in which order.
Own Id: OTP-14399
Checks that a ECDSA public key (ecdsa-sha2-nistp*) stored in a file has the correct size.
Own Id: OTP-14410

Ssh 4.4.2.4

Fixed Bugs and Malfunctions

Fix rare spurious shutdowns of ssh servers when receiving {'EXIT',_,normal} messages.
Own Id: OTP-15018
Host key hash erroneously calculated for clients following draft-00 of RFC 4419, for example PuTTY
Own Id: OTP-15064
Renegotiation could fail in some states
Own Id: OTP-15066

Ssh 4.4.2.3

Fixed Bugs and Malfunctions

An ssh_sftp server (running version 6) could fail if it is told to remove a file which in fact is a directory.
Own Id: OTP-15004

Ssh 4.4.2.2

Improvements and New Features

Default exec is disabled when a user-defined shell is enabled.
Own Id: OTP-14881

Ssh 4.4.2.1

Fixed Bugs and Malfunctions

Trailing white space was removed at end of the hello-string. This caused interoperability problems with some other ssh-implementations (e.g OpenSSH 7.3p1 on Solaris 11)
Own Id: OTP-14763 Aux Id: ERIERL-74

Ssh 4.4.2

Fixed Bugs and Malfunctions

ssh:daemon_info/1 crashed if the listening IP was not 'any'
Own Id: OTP-14298 Aux Id: seq13294

Ssh 4.4.1

Fixed Bugs and Malfunctions

Fix bug when opening connections. If the tcp setup failed, that would in some cases not result in an error return value.
Own Id: OTP-14108
Reduce information leakage in case of decryption errors.
Own Id: OTP-14109
The key exchange algorithm diffie-hellman-group-exchange-sha* has a server-option {dh_gex_limits,{Min,Max}}. There was a hostkey signature validation error on the client side if the option was used and the Min or the Max differed from the corresponding values obtained from the client.
This bug is now corrected.
Own Id: OTP-14166
The sftpd server now correctly uses root_dir and cwd when resolving file paths if both are provided. The cwd handling is also corrected.
Thanks to kape1395!
Own Id: OTP-14225 Aux Id: PR-1331, PR-1335
Ssh_cli used a function that does not handle non-utf8 unicode correctly.
Own Id: OTP-14230 Aux Id: ERL-364

Improvements and New Features

The implementation of the key exchange algorithms diffie-hellman-group-exchange-sha* are optimized, up to a factor of 11 for the slowest ( = biggest and safest) group size.
Own Id: OTP-14169 Aux Id: seq-13261
The ssh host key fingerprint generation now also takes a list of algorithms and returns a list of corresponding fingerprints. See public_key:ssh_hostkey_fingerprint/2 and the option silently_accept_hosts in ssh:connect.
Own Id: OTP-14223

Ssh 4.4

Fixed Bugs and Malfunctions

A file read with an sftp client could loose data if the packet_size is set to larger than 64k. This is corrected now in such a way that the packet_size is silently lowered if there is a risk for data loss.
Own Id: OTP-13857 Aux Id: ERL-238, OTP-13858
When user defined SSH shell REPL process exits with reason normal, the SSH channel callback module should report successful exit status to the SSH client. This provides simple way for SSH clients to check for successful completion of executed commands. (Thanks to isvilen)
Own Id: OTP-13905 Aux Id: PR-1173

Improvements and New Features

Extended the option silently_accept_hosts for ssh:connect to make it possible for the client to check the SSH host key fingerprint string. Se the reference manual for SSH.
Own Id: OTP-13887 Aux Id: OTP-13888

Ssh 4.3.6

Fixed Bugs and Malfunctions

Re-negotiation problems with OpenSSH client solved.
Own Id: OTP-13972

Ssh 4.3.5

Fixed Bugs and Malfunctions

If a client illegaly sends an info-line and then immediately closes the TCP-connection, a badmatch exception was raised.
Own Id: OTP-13966

Ssh 4.3.4

Fixed Bugs and Malfunctions

Intermittent ssh ERROR REPORT mentioning nonblocking_sender
Own Id: OTP-13953 Aux Id: seq13199

Ssh 4.3.3

Fixed Bugs and Malfunctions

Handle all possible exit values that should be interpreted as {error, closed}. Failing to do so could lead to unexpected crashes for users of the ssh application.
Own Id: OTP-13932 Aux Id: seq13189

Ssh 4.3.2

Fixed Bugs and Malfunctions

Upgrade of an established client connection could crash because the ssh client supervisors children had wrong type. This is fixed now.
Own Id: OTP-13782 Aux Id: seq13158
Partly checks the public key early in public key authorization
Own Id: OTP-13847 Aux Id: defensics-ssh3.1.0-190243,205277,219318
Corrected handling of SHA for ECDSA (Elliptic curve public keys)
Own Id: OTP-13850 Aux Id: defensics-ssh3.1.0-214168
Problems found by test suites as well as by Codenomicon/Defensics fixed: - reduce max random padding to 15 bytes (Codenomicon/Defensics) - inclomplete pdu handling (Codenomicon/Defensics) - badmatch in test suite - non-blocking send fixes deadlock in ssh_connection_SUITE:interrupted_send
Own Id: OTP-13854
Caller is now notified when a tcp close is received.
Own Id: OTP-13859 Aux Id: seq13177

Improvements and New Features

Use application:ensure_all_started/2 instead of hard-coding deps
Own Id: OTP-13843 Aux Id: PR-1147

Ssh 4.3.1

Fixed Bugs and Malfunctions

SSH client does not any longer retry a bad password given as option to ssh:connect et al.
Own Id: OTP-13674 Aux Id: TR-HU92273
Removed possible hanging risk for a certain timing sequence when communicating client and server executes on the same node.
Own Id: OTP-13715

Ssh 4.3

Improvements and New Features

A socket created and connected by gen_tcp could now be used as input to ssh:connect, ssh:shell, ssh_sftp:start_channel and ssh:daemon.
Own Id: OTP-12860
Some time optimization mainly in message encoding.
Own Id: OTP-13131
Optimized the sftp client time by setting new packet and window sizes.
Own Id: OTP-13175
The ssh_connection_handler module in SSH is changed and now uses the new behaviour gen_statem.
The module can be used as an example of a gen_statem callback module but with a warning: This commit of ssh is just a straightforward port from gen_fsm to gen_statem with some code cleaning. Since the state machine and the state callbacks are almost unchanged the ssh module does not demonstrate the full potential of the new behaviour.
The "new" state machine uses compound states. The ssh server and client state machines are quite similar but differences exist. With gen_fsm there were flags in the user data which in fact implemented "substates". Now with gen_statem those are made explicit in the state names, eg. the state userauth and the binary role-flag becomes the two state names {userauth, server} and {userauth, client}.
Own Id: OTP-13267
The {error, Reason} tuples returned from ssh_sftp api functions are described.
Own Id: OTP-13347 Aux Id: ERL-86
Added -spec in ssh
Own Id: OTP-13479
It is now possible to call ssh:daemon/{1,2,3} with Port=0. This makes the daemon select a free listening tcp port before opening it. To find this port number after the call, use the new function ssh:daemon_info/1. See the reference manual for details.
Own Id: OTP-13527

Ssh 4.2.2.6

Fixed Bugs and Malfunctions

Fix rare spurious shutdowns of ssh servers when receiving {'EXIT',_,normal} messages.
Own Id: OTP-15018

Ssh 4.2.2.5

Improvements and New Features

Default exec is disabled when a user-defined shell is enabled.
Own Id: OTP-14881

Ssh 4.2.2.4

Fixed Bugs and Malfunctions

Trailing white space was removed at end of the hello-string. This caused interoperability problems with some other ssh-implementations (e.g OpenSSH 7.3p1 on Solaris 11)
Own Id: OTP-14763 Aux Id: ERIERL-74

Ssh 4.2.2.3

Fixed Bugs and Malfunctions

The key exchange algorithm diffie-hellman-group-exchange-sha* has a server-option {dh_gex_limits,{Min,Max}}. There was a hostkey signature validation error on the client side if the option was used and the Min or the Max differed from the corresponding values obtained from the client.
This bug is now corrected.
Own Id: OTP-14166

Improvements and New Features

Key exchange algorithms diffie-hellman-group-exchange-sha* optimized, up to a factor of 11 for the slowest ( = biggest and safest) one.
Own Id: OTP-14169 Aux Id: seq-13261

Ssh 4.2.2.2

Fixed Bugs and Malfunctions

Upgrade of an established client connection could crash because the ssh client supervisors children had wrong type. This is fixed now.
Own Id: OTP-13782 Aux Id: seq13158

Ssh 4.2.2.1

Fixed Bugs and Malfunctions

SSH client does not any longer retry a bad password given as option to ssh:connect et al.
Own Id: OTP-13674 Aux Id: TR-HU92273

Ssh 4.2.2

Fixed Bugs and Malfunctions

Documentation correction of ssh_sftp:position/4
Thanks to Rabbe Fogelholm.
Own Id: OTP-13305 Aux Id: ERL-87

Ssh 4.2.1

Fixed Bugs and Malfunctions

The authentication method 'keyboard-interactive' failed in the Erlang client when the server after successful authentication continued by asking for zero more passwords.
Own Id: OTP-13225

Ssh 4.2

Fixed Bugs and Malfunctions

Better error handling in ssh_file. There was some rare errors when a NFS-mounted file was opened by ssh_file and then remotely deleted during reading. That caused an endless loop.
That bug is now fixed.
Own Id: OTP-12699 Aux Id: OTP-11688
Fixed a bug in the compression algorithm zlib@openssh.com.
Own Id: OTP-12759
It is now possible to start more than one daemon with a file descriptor given in option fd. Each daemon must of course have a unique file descriptor.
Own Id: OTP-12966 Aux Id: seq12945
Fixed a bug that caused the option dh_gex_limit to be ignored.
Own Id: OTP-13029
A problem is fixed with the ssh:connect option pref_public_key_algs specifying user keys.
Own Id: OTP-13158

Improvements and New Features

Document updates in the ssh reference manual: app doc file and ssh_connection.
Own Id: OTP-12003
The authorization phase is made stateful to prevent ssh acting on messages sent in wrong order.
Own Id: OTP-12787
Testcases for bad message lengths and for bad subfield lengths added.
Own Id: OTP-12792 Aux Id: Codenomicon #5214, 6166
The 'ecdsa-sha2-nistp256', 'ecdsa-sha2-nistp384' and 'ecdsa-sha2-nistp521' signature algorithms for ssh are implemented. See RFC 5656.
Own Id: OTP-12936
The crypto algorithms 'aes192-ctr' and 'aes256-ctr' are implemented. See RFC 4344.
Own Id: OTP-12939
The ciphers and macs AEAD_AES_128_GCM and AEAD_AES_256_GCM are implemented but not enabled per default. See the SSH App Reference Manual and RFC5647 for details.
The ciphers aes128-gcm@openssh.com and aes256-gcm@openssh.com are also implemented and available in the default configuration.
Own Id: OTP-13018
The ssh:daemon option dh_gex_groups is extended to read a user provided ssh moduli file with generator-modulus pairs. The file is in openssh format.
Own Id: OTP-13052 Aux Id: OTP-13054
There is now a file (public_key/priv/moduli) which lists size-generator-modulus triples. The purpose is to give servers the possibility to select the crypto primes randomly among a list of pregenerated triples. This reduces the risk for some attacks on diffie-hellman negotiation.
See the reference manual for public_key:dh_gex_group/4 where the handling of this is described.
The ssh server (ssh:daemon) uses this.
Own Id: OTP-13054 Aux Id: OTP-13052
The ssh:daemon option pwdfun now also takes a fun/4. This enables the user to 1) check userid-password in another way than the builtin algorithm, 2) implement rate limiting per user or source IP or IP+Port, and 3) implement blocking of missbehaving peers.
The old fun/2 still works as previously.
Own Id: OTP-13055 Aux Id: OTP-13053
There is now a new option to make the server limit the size range of moduli available for the diffie-hellman group exchange negotiation. See option {dh_gex_limits,{Min,Max}} in ssh:daemon/3.
Own Id: OTP-13066
Ecdh key exchange now validates compressed and uncompressed keys as defined in rfc5656
Own Id: OTP-13067
Search order for the .ssh directory are changed so $HOME is tried before init:get_argument(home).
Own Id: OTP-13109
The sftp receive window handling is optimized so it will not update the remote end too often. This makes "sftp mget" considerable faster.
Own Id: OTP-13130
The option key_cb is extended to take an optional list that is passed to the callback module as an option. With this it is possible to have different keys depending on which host that is connected. Another possibility is to write a callback module that fetches keys etc from a database.
Thanks to Vipin Nair.
Own Id: OTP-13156

Ssh 4.1.3

Known Bugs and Problems

SSH_MSG_KEX_DH_GEX_REQUEST_OLD implemented to make PuTTY work with erl server.
Own Id: OTP-13140

Ssh 4.1.2

Fixed Bugs and Malfunctions

Add a 1024 group to the list of key group-exchange groups
Own Id: OTP-13046

Ssh 4.1.1

Improvements and New Features

A new option max_channels limits the number of channels with active server-side subsystems that are accepted.
Own Id: OTP-13036

Ssh 4.1

Fixed Bugs and Malfunctions

Send an understandable disconnect message when the key exchange phase can't find a common algorithm. There are also some test cases added.
Own Id: OTP-11531
The third parameter in ssh_sftp:write_file is now accepting iolists again. Unicode handling adjusted.
Own Id: OTP-12853 Aux Id: seq12891

Improvements and New Features

First part of ssh test suite re-organization and extension.
Own Id: OTP-12230
The key exchange algorithms 'ecdh-sha2-nistp256', 'ecdh-sha2-nistp384' and 'ecdh-sha2-nistp521' are implemented. See RFC 5656.
This raises the security level considerably.
Own Id: OTP-12622 Aux Id: OTP-12671, OTP-12672
The key exchange algorithm 'diffie-hellman-group14-sha1' is implemented. See RFC 4253.
This raises the security level.
Own Id: OTP-12671 Aux Id: OTP-12672, OTP-12622
The key exchange algorithms 'diffie-hellman-group-exchange-sha1' and 'diffie-hellman-group-exchange-sha256' are implemented. See RFC 4419.
This raises the security level.
Own Id: OTP-12672 Aux Id: OTP-12671, OTP-12622
Adding random length extra padding as recommended in RFC 4253 section 6.
Own Id: OTP-12831
New test library for low-level protocol testing. There is also a test suite using it for some preliminary tests. The intention is to build on that for more testing of individual ssh messages. See lib/ssh/test/ssh_trpt_test_lib.erl and ssh_protocol_SUITE.erl in the same directory.
Own Id: OTP-12858
Increased default values for diffie-hellman-group-exchange-sha* to Min = 1024, N = 6144, Max = 8192.
Added 6144 and 8192 bit default gex groups.
Own Id: OTP-12937
The mac algorithm 'hmac-sha2-512' is implemented. See RFC 6668.
Own Id: OTP-12938

Ssh 4.0

Fixed Bugs and Malfunctions

Ssh crashed if a message was sent on a channel with packet_size = 0.
A new option for ssh:daemon is also introduced: minimal_remote_max_packet_size. This option sets the least max packet size declaration that the daemon will accept from a client. The default value is 0 to maintain compatibility with OpenSSH and the rfc:s.
Own Id: OTP-12645 Aux Id: seq12816
Included test of the 'e' and 'f' parameters in diffie-hellman key exchange as specified in rfc 4253 section 8.
Own Id: OTP-12649
Fixes the bug that once the rekey_limit bytes (by default, 1GB) had been transmitted the connection was rekeyed every minute, not after the next transferred 'rekey_limit' chunk.
Thanks to Simon Cornish for the report and the fix!
Own Id: OTP-12692
Fixes a bug that causes an SFTP connection to always fail when {timeout, Timeout} option is used with ssh_sftp:start_channel.
Thanks to Simon Cornish
Own Id: OTP-12708
Fix various ssh key exchange problems.
Thanks to Simon Cornish
Own Id: OTP-12760 Aux Id: pull req 715
The options system_dir and user_dir assumes that the value is a path to a directory which is readable. This is now checked early, so ssh:daemon and ssh:connect will fail with an error message immediately.
Own Id: OTP-12788
A daemon now checks that a client doesn't try to authorize with methods not in the option auth_methods.
Own Id: OTP-12790
Disconnectfun now should trigger on all disconnects.
Own Id: OTP-12811

Improvements and New Features

Better usage of binary matching in ssh_auth.erl and ssh_message.erl
Own Id: OTP-11697
A new option 'preferred_algorithms' is available for ssh:daemon and ssh:connect.
This option defines the algorithms presented to the peer in the algorithm negotiation phase of the ssh protocol.
The default list can be obtained from the new function ssh:default_algorithms/0.
* INCOMPATIBILITY with removed undocumented options 'role' and 'compression' *
Own Id: OTP-12029
The internal group to user_drv protocol has been changed to be synchronous in order to guarantee that output sent to a process implementing the user_drv protocol is printed before replying. This protocol is used by the standard_output device and the ssh application when acting as a client.
This change changes the previous unlimited buffer when printing to standard_io and other devices that end up in user_drv to 1KB.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-12240
If ssh_connection:subsystem/4 fails we do not want to crash but rather terminate gracefully.
Own Id: OTP-12648 Aux Id: seq12834
New option id_string for ssh:daemon and ssh:connect for limiting banner grabbing attempts.
The possible values are: {id_string,string()} and {id_string,random}. The latter will make ssh generate a random nonsense id-string for each new connection.
Own Id: OTP-12659
To enable the ssh daemon to run in a virtualized environment, where there can be more that one server that has the same ip-address and port, we add a new option profile.
Own Id: OTP-12675
Upgrade test suite added.
Own Id: OTP-12676
A new option for handling the SSH_MSG_DEBUG message's printouts. A fun could be given in the options that will be called whenever the SSH_MSG_DEBUG message arrives. This enables the user to format the printout or just discard it.
Own Id: OTP-12738 Aux Id: seq12860
Testcase improvements and corrections:
* Add testcases for the disconnectfun option on both server and client sides
* Timeout testcases adjusted for slow machines where they sometimes failed
Own Id: OTP-12786
The option disconnectfun can now be used both on the client and server side.
Own Id: OTP-12789
A new option unknown_msgfun/2 for ssh:connect and ssh:daemon for handling unknown messages. With the option it is possible to intercept before an INFO log message is generated.
One usage is to filter out messages that are not wanted in the error logger as info reports. An example of such a message is the 'etimedout' tcp error message that will be received if a connection has keep_alive and the peer is restarted.
Own Id: OTP-12813 Aux Id: seq12881

Ssh 3.2.4

Fixed Bugs and Malfunctions

Gracefully terminate if sockets is unexpectedly closed.
Own Id: OTP-12782
Made Codenomicon Defensics test suite pass:
- limit number of algorithms in kexinit message
- check 'e' and 'f' parameters in kexdh
- implement 'keyboard-interactive' user authentication on server side
- return plain text message to bad version exchange message
Own Id: OTP-12784

Ssh 3.2.3

Fixed Bugs and Malfunctions

A new option for handling the SSH_MSG_DEBUG message's printouts. A fun could be given in the options that will be called whenever the SSH_MSG_DEBUG message arrives. This enables the user to format the printout or just discard it.
Own Id: OTP-12738 Aux Id: seq12860

Ssh 3.2.2

Improvements and New Features

New option id_string for ssh:daemon and ssh:connect for limiting banner grabbing attempts.
The possible values are: {id_string,string()} and {id_string,random}. The latter will make ssh generate a random nonsense id-string for each new connection.
Own Id: OTP-12659

Ssh 3.2.1

Fixed Bugs and Malfunctions

Ssh crashed if a message was sent on a channel with packet_size = 0.
A new option for ssh:daemon is also introduced: minimal_remote_max_packet_size. This option sets the least max packet size declaration that the daemon will accept from a client. The default value is 0 to maintain compatibility with OpenSSH and the rfc:s.
Own Id: OTP-12645 Aux Id: seq12816

Ssh 3.2

Fixed Bugs and Malfunctions

If a channel is closed by the peer while using a function with call semantics in ssh_connection.erl return {error, closed}. Document that the functions can return {error, timeout | closed} and not only ssh_request_status()
Own Id: OTP-12004
Bug that causes ssh:connect to return {error,int()} instead of {error,timeout} when ssh handshake takes too long time.
Own Id: OTP-12369
Documentation corrections. (Thanks to Rabbe Fogelholm)
Own Id: OTP-12399

Improvements and New Features

Example of ssh_connection:exec added.
Own Id: OTP-12558

Ssh 3.1

Fixed Bugs and Malfunctions

Make sure the clean rule for ssh, ssl, eunit and otp_mibs actually removes generated files.
Own Id: OTP-12200
Improved Property Tests (Thanks to Thomas, John and Tobias at QuviQ)
Own Id: OTP-12256
Correct typo of renegotiate that could cause rekeying to fail
Own Id: OTP-12277 Aux Id: seq12736
The {timeout, Timeout} option passed to ssh_sftp:start_channel was not applied to the early phases of the SSH protocol. This patch passes the Timeout through to ssh:connect. In case the timeout occurs during these phases, {error, timeout} is returned. (Thanks to Simon Cornish)
Own Id: OTP-12306

Improvements and New Features

Added API functions ptty_alloc/3 and ptty_alloc/4, to allocate a pseudo tty.
Own Id: OTP-11542 Aux Id: seq12493, OTP-11631
Supports tar file creation on other media than file systems mounted on the local machine.
The erl_tar api is extended with erl_tar:init/3 that enables usage of user provided media storage routines. A ssh-specific set of such routines is hidden in the new function ssh_sftp:open_tar/3 to simplify creating a tar archive on a remote ssh server.
A chunked file reading option is added to erl_tar:add/3,4 to save memory on e.g small embedded systems. The size of the slices read from a file in that case can be specified.
Own Id: OTP-12180 Aux Id: seq12715
Always send SSH_DISCONNECT protocol messages when peer sends corrupt messages.
Own Id: OTP-12185
Hooks for funs that can change binaries sent to remote sites from erl_tar for renote tar file creation are added. See ssh_sftp:open_tar/3,4 for details. The hooks could also be used to read remote tar files that need transformation before file extraction.
Those hooks are intended for encryption and decryption of tar files. Effort is put into memory, disk and network resource economy.
Own Id: OTP-12312 Aux Id: OTP-12180

Ssh 3.0.8

Fixed Bugs and Malfunctions

Fixes of login blocking after port scanning.
Own Id: OTP-12247 Aux Id: seq12726

Ssh 3.0.7

Fixed Bugs and Malfunctions

Add option sftp_vsn to SFTP
Own Id: OTP-12227

Improvements and New Features

Fix option user_interaction to work as expected. When password authentication is implemented with ssh keyboard-interactive method and the password is already supplied, so that we do not need to query user, then connections should succeed even though user_interaction option is set to false.
Own Id: OTP-11329 Aux Id: seq12420, seq12335

Ssh 3.0.6

Fixed Bugs and Malfunctions

Gracefully handle bad data from the client when expecting ssh version exchange.
Own Id: OTP-12157 Aux Id: seq12706
When restarting an ssh daemon, that was stopped with ssh:stop_listner/ [1,2] new options given shall replace old ones.
Own Id: OTP-12168 Aux Id: seq12711

Improvements and New Features

ssh now has a format_status function to avoid printing sensitive information in error loggs.
Own Id: OTP-12030

Known Bugs and Problems

The option parallel_login didn't work with the value true. All logins were serial.
Own Id: OTP-12194

Ssh 3.0.5

Fixed Bugs and Malfunctions

When starting an ssh-daemon giving the option {parallel_login, true}, the timeout for authentication negotiation ({negotiation_timeout, integer()}) was never removed.
This caused the session to always be terminated after the timeout if parallel_login was set.
Own Id: OTP-12057 Aux Id: seq12663

Improvements and New Features

Warning: this is experimental and may disappear or change without previous warning.
Experimental support for running Quickcheck and PropEr tests from common_test suites is added to common_test. See the reference manual for the new module ct_property_testing.
Experimental property tests are added under lib/{inet,ssh}/test/property_test. They can be run directly or from the commont_test suites inet/ftp_property_test_SUITE.erl and ssh/test/ssh_property_test_SUITE.erl.
See the code in the test directories and the man page for details.
(Thanks to Tuncer Ayaz for a patch adding Triq)
Own Id: OTP-12119

Ssh 3.0.4

Fixed Bugs and Malfunctions

When starting an ssh-daemon giving the option {parallel_login, true}, the timeout for authentication negotiation ({negotiation_timeout, integer()}) was never removed.
This caused the session to always be terminated after the timeout if parallel_login was set.
Own Id: OTP-12057 Aux Id: seq12663

Ssh 3.0.3

Fixed Bugs and Malfunctions

Removed mail address from error reports and corrected spelling error (Stacktace -> stacktrace)
Own Id: OTP-11883 Aux Id: seq12586
Decode/encode fixes in SSH_MSG_IGNORE and SSH_MSG_UNIMPLEMENTED.
Own Id: OTP-11983

Improvements and New Features

Accepts that some older OpenSSH clients sends incorrect disconnect messages.
Own Id: OTP-11972
Handle inet and inet6 option correctly
Own Id: OTP-11976

Ssh 3.0.2

Fixed Bugs and Malfunctions

Fixed timeout bug in ssh:connect.
Own Id: OTP-11908

Improvements and New Features

Option max_sessions added to ssh:daemon/{2,3}. This option, if set, limits the number of simultaneous connections accepted by the daemon.
Own Id: OTP-11885

Ssh 3.0.1

Fixed Bugs and Malfunctions

Fixes the problem that ssh_cli in some cases could delay the prompt if a tty was not requested by the client.
Own Id: OTP-10732
The variable NewCol is now correctly calculated allowing for tab-completion of function calls even when preceded with blank space (Thanks to Alexander Demidenko)
Own Id: OTP-11566
Fix incorrect dialyzer spec and types, also enhance documentation.
Thanks to Ayaz Tuncer.
Own Id: OTP-11627
Fixed a bug when ssh:exec executes a linux command on a linux ssh daemon. If the result is sent back from standard error, the length information was not stripped off correctly.
Own Id: OTP-11667
Fixed a bug with the ssh file 'known_hosts' which made the file grow with many equal entries.
Own Id: OTP-11671
Some local implementations of removing the last element from a list are replaced by lists:droplast/1. Note that this requires at least stdlib-2.0, which is the stdlib version delivered in OTP 17.0. (Thanks to Hans Svensson)
Own Id: OTP-11678
Bug fix for ssh:daemon/2,3 so that the failfun is called when it should.
Own Id: OTP-11680
Fixed bug which crashed ssh when SSH_MSG_KEX_DH_GEX_GROUP is received. This could cause a vm-crash for eheap_alloc during garbage collect.
Own Id: OTP-11696 Aux Id: 12547, 12532
Fixes a bug that breaks keyboard-interactive authentication. Thanks to Simon Cornish for reporting and suggesting a fix.
Own Id: OTP-11698
dialyzer specs are now correct for ssh:start/0, ssh:start/1, ssh:stop/0 and ssh_connection_handler:open_channel/5. (Thanks to Johannes Weißl )
Own Id: OTP-11705
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
Fixed dialyzer warning for ssh_connection:send.
Own Id: OTP-11821
ssh:daemon/2,3 : Added options negotiation_timeout and parallel_login to tune the authentication behaviour.
Own Id: OTP-11823

Improvements and New Features

Ssh now fully supports unicode filenames, filecontents, shell and cli. Please note that the underlying os and emulator must also give support for unicode. You may want to start the emulator with "erl +fnu" on Linux.
Own Id: OTP-10953

Ssh 3.0

Fixed Bugs and Malfunctions

The ssh cli is now faster at close and before new prompt.
Own Id: OTP-11339 Aux Id: seq12423
Ssh process structure was redesigned to better map to what is truly parallel this has solved a lot of strange timing issues that sometimes would occur, for instance a process leak could happen when a lot of connections where taken up and down in parallel in a short period of time. Also backwards compatible clauses to "original" but never supported features has been removed.
Impact: Increases flow efficiency
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-11363
Fix various typos in erts, kernel and ssh. Thanks to Martin Hässler.
Own Id: OTP-11414
Correct private_key type documentation in ssh_server_key_api. Thanks to Tristan Sloughter.
Own Id: OTP-11449
The functions in ssh_no_io.erl did not mimic the functions in ssh_io.erl correctly, the arity was incorrect for some functions which caused ssh to fail in the wrong way.
Own Id: OTP-11490

Improvements and New Features

Add option to disallow CLI
Own Id: OTP-10976
Add sockname and user to ssh:connection_info/2
Own Id: OTP-11296

Ssh 2.1.8

Improvements and New Features

Do not chmod ~/.ssh unnecessarily.
Own Id: OTP-11189
Make ssh_cli.erl handle CTRL+C. Thanks to Stefan Zegenhagen.
Own Id: OTP-11199
Clarified timeout options in documentation.
Own Id: OTP-11249
Add openssh_zlib compression type to ssh_transport. Thanks to Louis-Philippe Gauthier.
Own Id: OTP-11256

Ssh 2.1.7

Fixed Bugs and Malfunctions

ssh:daemon will get fed with an argument even if it is not a valid expression.
Own Id: OTP-10975

Improvements and New Features

Properly ignore everything in lib/ssh-5.2.1/doc/html/. Thanks to Anthony Ramine.
Own Id: OTP-10983
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

Ssh 2.1.6

Fixed Bugs and Malfunctions

Fixed timing rekeying bug.
Own Id: OTP-10940

Ssh 2.1.5

Fixed Bugs and Malfunctions

Bug in rekeying for daemon fixed.
Own Id: OTP-10911

Improvements and New Features

Enhanced error message and added test for ssh clients trying to start non existing subsystems.
Own Id: OTP-10714

Ssh 2.1.4

Improvements and New Features

Better quality on the error messages for when key exchange failed.
Own Id: OTP-10553 Aux Id: seq12152
Fix link to documentation for ssh:connect/3,4. Thanks to Martin Hässler.
Own Id: OTP-10862

Ssh 2.1.3

Fixed Bugs and Malfunctions

It is now possible to send an empty binary using ssh_connection:send/3, this corner case previously caused ssh_connection:send to hang.
Own Id: OTP-9478 Aux Id: kunagi-226 [137]
Fix typo in keyboard-interactive string. Thanks to Daniel Goertzen
Own Id: OTP-10456
ssh_connectino:send/3 will not return until all data has been sent. Previously it could return too early, resulting in things such premature close of the connection. Also improved error handling of closed SSH channels.
Own Id: OTP-10467
Fixed ssh_cli.erl crashes because #state.buf is yet 'undefined'.
Fixed Client terminateing connections due to channel_request message response is sent to the wrong id.
Affected SSH clients: - all clients based on SSH-2.0-TrileadSSH2Java_213 (problem #1) - SSH Term Pro (problem #2)
Thanks to Stefan Zegenhagen
Own Id: OTP-10475
Fixed various syntax errors in SSH appup file
Own Id: OTP-10657

Improvements and New Features

SSH_FX_FILE_IS_A_DIRECTORY message for sftp implemented
Own Id: OTP-6406 Aux Id: kunagi-218 [129]
SSH Rekeying fixed
Own Id: OTP-7785 Aux Id: kunagi-220 [131]
Added User Guide for the SSH application
Own Id: OTP-7786 Aux Id: kunagi-221 [132]
Documentation regarding failfun, connectfun and disconnectfun provided
Own Id: OTP-7792 Aux Id: kunagi-222 [133]
SSH connection timer implementation
New option, {idle_time, integer()}, sets a timeout on connection when no channels are active, defaults to infinity
Own Id: OTP-10514 Aux Id: seq12020
Some examples overflowing the width of PDF pages have been corrected.
Own Id: OTP-10665
Fixed internal error on when client and server cannot agree o which authmethod to use.
Own Id: OTP-10731 Aux Id: seq12237

Ssh 2.1.2.1

Improvements and New Features

Removed error report in ssh_connection_handler triggered by badmatch failure.
Own Id: OTP-11188

Ssh 2.1.2

Fixed Bugs and Malfunctions

SSH quiet mode
A new option to ssh:connect/3,4, quiet_mode. If true, the client will not print out anything on authorization.
Own Id: OTP-10429 Aux Id: kunagi-273 [184]
Restrict which key algorithms to use
A new option to ssh:connect/3,4 is introduced, public_key_algs, where you can restrict which key algorithms to use and in which order to try them.
Own Id: OTP-10498 Aux Id: kunagi-289 [200]
Confidentiality of client password
Unsets clients password after authentication.
Own Id: OTP-10511 Aux Id: kunagi-292 [203]
Fixed user interaction for SSH
It's now available to accept hosts and input password
Own Id: OTP-10513 Aux Id: kunagi-293 [204]

Ssh 2.1.1

Fixed Bugs and Malfunctions

Ssh now only sends one channel close message under all circumstances, before it would sometimes incorrectly send two.
Own Id: OTP-10060
The options check mistreated the ip_v6_disable-option, and did not handle some, at the moment, undocumented options correctly.
Own Id: OTP-10061
The channel id in a channel failure message, sent to the peer, is now in all cases the remote channel id
Own Id: OTP-10062
Improved handling of multiple closes to avoid occasional crashes when a channel is closed more than once.
Own Id: OTP-10112
Fix lib/src/test/ssh_basic_SUITE.erl to fix IPv6 option typos
Fixed incorrect option "ipv6_disable" to "ipv6_disabled" as documented in the ssh manual.
Own Id: OTP-10219
SSH: Make "auth_methods" server option re-usable
The 'auth_methods' option is used by the server side of the SSH code to tell a connecting SSH client about the authentication methods that are supported by the server. The code still extracts and handles the 'auth_methods' option from Opts in appropriate places, but the Opts checking code in ssh.erl didn't allow that option to be specified.
Own Id: OTP-10224
Use the correct channel id when adjusting the channel window
Own Id: OTP-10232

Ssh 2.1

Fixed Bugs and Malfunctions

All keys in authorized_keys are considered, wrongly only the first one was before.
Own Id: OTP-7235
ssh daemon now properly handles ras host keys, in previous versions only dsa host keys sufficed to set up a connection.
Own Id: OTP-7677
ssh:shell/3 and ssh:connect/3 does not hang anymore if connection negotiation fails
Own Id: OTP-8111
Improve check so that we will not try to read ssh packet length indicator if not sure we have enough data.
Own Id: OTP-8380
Do not try to use user interaction when it is disabled.
Own Id: OTP-9466 Aux Id: seq11886
Improved error handling of internal errors i the ssh connection handling process
Own Id: OTP-9905
sftp daemon generates file handles correct
Own Id: OTP-9948

Improvements and New Features

Document supported algorithms
Own Id: OTP-8109
Graceful handling of premature close from an sftp client.
Own Id: OTP-9391 Aux Id: seq11838
Changed ssh implementation to use the public_key application for all public key handling. This is also a first step for enabling a callback API for supplying public keys and handling keys protected with password phrases.
Additionally the test suites where improved so that they do not copy the users keys to test server directories as this is a security liability. Also ipv6 and file access issues found in the process has been fixed.
This change also solves OTP-7677 and OTP-7235
This changes also involves some updates to public_keys ssh-functions.
Own Id: OTP-9911
Added options for the ssh client to support user keys files that are password protected.
Own Id: OTP-10036 Aux Id: OTP-6400, Seq10595

Ssh 2.0.9

Improvements and New Features

Erlang/OTP can now be built using parallel make if you limit the number of jobs, for instance using 'make -j6' or 'make -j10'. 'make -j' does not work at the moment because of some missing dependencies.
Own Id: OTP-9451
Ssh behaviours now use the new directive "-callback". Parameters will be further specified in a later version of ssh.
Own Id: OTP-9796

Ssh 2.0.8

Fixed Bugs and Malfunctions

Calling ssh_sftp:stop_channel/1 resulted in that the trap_exit flag was set to true for the invoking process.
Own Id: OTP-9386 Aux Id: seq11865

Ssh 2.0.7

Fixed Bugs and Malfunctions

An unexpected message would crash the ssh_connection_handler and close the connection. Now an error message is generated instead.
Own Id: OTP-9273

Ssh 2.0.6

Fixed Bugs and Malfunctions

A memory leak has been fixed. I.e. per terminated connection the size of a pid and the length of a user name string was not cleared.
Own Id: OTP-9232

Ssh 2.0.5

Improvements and New Features

Strengthened random number generation. (Thanks to Geoff Cant)
Own Id: OTP-9225

Ssh 2.0.4

Fixed Bugs and Malfunctions

In some cases SSH returned {error, normal} when a channel was terminated unexpectedly. This has now been changed to {error, channel_closed}.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-8987 Aux Id: seq11748
SSH did not handle the error reason enetunreach when trying to open a IPv6 connection.
Own Id: OTP-9031

Improvements and New Features

It is now possible to use SSH to sign and verify binary data.
Own Id: OTP-8986
SSH now ensures that the .ssh directory exists before trying to access files located in that directory.
Own Id: OTP-9010

Ssh 2.0.3

Fixed Bugs and Malfunctions

The fix regarding OTP-8849 was not included in the previous version as stated.
Own Id: OTP-8918

Ssh 2.0.2

Fixed Bugs and Malfunctions

The ssh_system_sup did not catch noproc and shutdown messages.
Own Id: OTP-8863
In some cases a crash report was generated when a connection was closing down. This was caused by a race condition between two processes.
Own Id: OTP-8881 Aux Id: seq11656, seq11648

Improvements and New Features

SSH no longer use deprecated public_key functions.
Own Id: OTP-8849

Ssh 2.0.1

Fixed Bugs and Malfunctions

SSH in some cases terminated channels with reason normal when it should have been shutdown.
Own Id: OTP-8714
SSH in some cases generated a crash report when a channel was closed in a normal way.
Own Id: OTP-8735 Aux Id: seq11615
The processes ssh_subsystem_sup and one ssh_channel_sup was not terminated when a connection was closed.
Own Id: OTP-8807

Ssh 2.0

Fixed Bugs and Malfunctions

The function ssh:connect/4 was not exported.
Own Id: OTP-8550 Aux Id:
Aligned error message with used version (SSH_FX_FAILURE vs SSH_FX_NOT_A_DIRECTORY, the latter introduced in version 6).
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-8644 Aux Id: seq11574
Resolved race condition when another connection is started before a channel is opened in the first connection.
Own Id: OTP-8645 Aux Id: seq11577

Improvements and New Features

The configuration parameter ip_v6_disabled is now available, which makes it possible for the user to alter the IP version SSH shall use.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-8535 Aux Id:
The ssh_connection:send operation now accepts infinity as timeout.
Own Id: OTP-8534 Aux Id:
The connection handler now include stack traces when a channel message is not handled correctly.
Own Id: OTP-8524 Aux Id:
Removed deprecated modules (ssh_ssh, ssh_sshd and ssh_cm) and functions (ssh_sftp:connect and ssh_sftp:stop).
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-8596 Aux Id:

Ssh 1.1.8

Fixed Bugs and Malfunctions

In some cases SSH ceased to collect more data from the transport layer.
Own Id: OTP-8401 Aux Id: seq11479

Improvements and New Features

Old release notes removed.
Own Id: OTP-8356 Aux Id:

Ssh 1.1.7

Fixed Bugs and Malfunctions

Now clear all processes when a connection is terminated.
Own Id: OTP-8121 Aux Id:
In some rare cases the connection handler could enter an infinite loop.
Own Id: OTP-8277 Aux Id: seq11428
If an SFTP server did not respond with EOF, the function ssh_sftp:list_dir/2/3 would enter an infinite loop.
Own Id: OTP-8278 Aux Id: seq11450

Improvements and New Features

The documentation is now built with open source tools (xsltproc and fop) that exists on most platforms. One visible change is that the frames are removed.
Own Id: OTP-8201 Aux Id:

Ssh 1.1.6

Fixed Bugs and Malfunctions

ssh_sftp:start_channel did not handle all possible return values from ssh_channel:start correctly.
Own Id: OTP-8176 Aux Id:
SFTPD did not handle rename command (version 4) correctly.
Own Id: OTP-8175 Aux Id: seq11373
If a connection manager already had been terminated it could cause a channel to generate a crash report when it was about to stop.
Own Id: OTP-8174 Aux Id: seq11377
Requests could result in badarg or badmatch EXIT messages in the connection manager if the channel no longer existed.
Own Id: OTP-8173 Aux Id: seq11379
ssh_transport:unpack/3 could cause a badarg error.
Own Id: OTP-8162 Aux Id:

Improvements and New Features

The encryption algorithm aes128-cbc is now supported. Requires that crypto-1.6.1 is available.
Own Id: OTP-8110 Aux Id:

Ssh 1.1.5

Fixed Bugs and Malfunctions

ssh_sftp:start_channel/3 did not handle timeout correctly.
Own Id: OTP-8159 Aux Id: seq11386
If a progress message was not received after invoking ssh:connect/3 the call could hang for ever. A timeout option has also been added.
Own Id: OTP-8160 Aux Id: seq11386
A comma has been missing in the ssh.appup file since SSH-1.0.2.
Own Id: OTP-8161 Aux Id:

Ssh 1.1.4

Fixed Bugs and Malfunctions

SSH sometimes caused a crash report at disconnect.
Own Id: OTP-8071 Aux Id: seq11319

Ssh 1.1.3

Fixed Bugs and Malfunctions

The operation ssh_sftp:stop_channel/1 returned an exception if the connection already had been closed.
Own Id: OTP-7996 Aux Id: seq11281
SSH did not handle if supervisor:start_child/2 returned {error, already_present}.
Own Id: OTP-8034 Aux Id: seq11307
SSH no longer cause supervisor reports when a connection is terminated in a controlled manner.
Own Id: OTP-8035 Aux Id: seq11308

Ssh 1.1.2

Fixed Bugs and Malfunctions

Ssh confused local and remote channel id's, which in some cases resulted in that messages were discarded.
Own Id: OTP-7914 Aux Id: seq11234
Ssh could not handle echo values other than 0 and 1.
Own Id: OTP-7917 Aux Id: seq11238
A crash occurred if a non-valid channel reference was received.
Own Id: OTP-7918 Aux Id: seq11238
Sftpd connections was not closed after receiving eof from a client.
Own Id: OTP-7921 Aux Id: seq11222
It was not possible to start a SFTP subsystem on certain platforms, i.e. those who do not support symbolic links.
Own Id: OTP-7930 Aux Id:
In some cases the message {ssh_cm, ssh_connection_ref(), {closed, ssh_channel_id()}} was not passed to the registered callback module.
Own Id: OTP-7957 Aux Id:

Improvements and New Features

By using the sftpd option {max_files, Integer}, the message size for READDIR commands can be reduced.
Own Id: OTP-7919 Aux Id: seq11230

Ssh 1.1.1

Fixed Bugs and Malfunctions

The erlang ssh server has presented itself incorrectly, using the special version ssh-1.99, although it never has supported versions below 2.0. Since ssh-1.1 client versions below 2.0 are correctly rejected instead of letting the server crash later on. Alas the problem with the presentation string was not discovered until after ssh.1.1 was released. Now the server will present itself as ssh-2.0.
Own Id: OTP-7795
An internal function call used an incorrect parameter, which caused problem when the old listen API was used. This was introduced in Ssh-1.1.
Own Id: OTP-7920 Aux Id: seq11211

Improvements and New Features

Ssh timeouts will now behave as expected i.e. defaults to infinity only the user of the ssh application can know of a reasonable timeout value for their application.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-7807
The implementation of timeouts added as a patch in ssh-1.0.1 was slightly changed and is now documented.
Own Id: OTP-7808
To honor the multiplexing of channels over one ssh connection concept ssh_sftp:connect/ [1,2,3] is deprecated and replaced by ssh_sftp:start_channel/[1,2,3] and ssh_sftp:stop/1 is deprecated and replaced by ssh_sftp:stop_channel/1 and to stop the ssh connection ssh:close/ 1 should be called.
Own Id: OTP-7809
Added the message {ssh_channel_up, ChannelId, ConnectionManager} that shall be handled by the channel callback handle_msg/2. This makes the function handle_msg/2 a mandatory function for ssh channels implementations which it was not in ssh-1.1.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-7828

Ssh 1.1

Fixed Bugs and Malfunctions

A flaw in the implementation of the supervision tree caused the ssh daemon to close the connections to all currently logged in users if one user logged out. Another problem related to the supervision tree caused the closing down of clients to leak processes i.e. all processes was not shutdown correctly.
Own Id: OTP-7676
Tabs could cause ssh_cli to print things in a surprising way.
Own Id: OTP-7683 Aux Id: seq11102
[sftp, sftpd] - Added patch to make sftp timestamps more correct, in the long run it would be nice to have better support in file to be able to make it always behave correctly now it will be correct 99 % of time instead of almost never correct, at least on unix-based platforms.
Own Id: OTP-7685 Aux Id: seq11082
[sftpd] - Added patch to further improve handling of symbolic links in the sftp-server.
Own Id: OTP-7766 Aux Id: seq11101
Ssh incorrectly sent the local id instead of the remote id of a channel to the peer. For simpler cases these ids often happen to have the same value. One case when they do not is when the client sends an exec command two times in a raw on the same ssh connection (different channels of course as the channel will be closed when the exec command has been evaluated) .
Own Id: OTP-7767
Packet data could be lost under high load due to the fact that buffered data was sometimes wrongly discarded before it had been sent.
Own Id: OTP-7768
Improved ipv6-handling as some assumptions about inet functions where incorrect.
Own Id: OTP-7770

Improvements and New Features

Added new API function ssh:connection_info/2.
Own Id: OTP-7456
Now starts ssh channel processes later avoiding synchronization problems between processes.
Own Id: OTP-7516
Ssh now rejects old versions of the ssh protocol for security reasons. (Even if they where not correctly rejected before the connection would probably have failed anyway due to other reasons.)
Own Id: OTP-7645 Aux Id: seq11094
New API module ssh_channel has been added. This is a behaviour to facilitate the implementation of ssh clients and plug in subsystems to the ssh daemon. Note that this slightly changes the options to the API function ssh:daemon/[1,2,3] deprecating all no longer documented options. Note that the new API enforces the "logical way" of using the old API i.e. making the subsystem process part of the ssh applications supervisor tree, so missuses of the old API are not compatible with the new API.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-7769

Known Bugs and Problems

Public keys protected by a password are currently not handled by the erlang ssh application.
Own Id: OTP-6400 Aux Id: 10595

Ssh 1.0.2

Fixed Bugs and Malfunctions

[sftpd] - Listing of symbolic link directories should now work as expected.
Own Id: OTP-7141 Aux Id: seq10856

Ssh 1.0.1

Fixed Bugs and Malfunctions

[sftp] - When listing a directory with more than 100 files only the first 100 where listed. This has now been fixed.
Own Id: OTP-7318 Aux Id: seq10953
When restarting an ssh-system the expected return value from ssh_system_sup:restart_acceptor/2 was incorrect, this is no longer the case.
Own Id: OTP-7564 Aux Id: seq11055
A few minor bugs where fixed in ssh_userreg.erl and ssh_connection_manager and a a ssh_cli option was added to restore backwards compatibility with the old ssh_cm - API.
Own Id: OTP-7565
Fixed bug in ipv6 support and added option to disable ipv6 as a workaround for badly configured computers.
Own Id: OTP-7566

Improvements and New Features

[sftp] - Option added to set timeout value in sftp.
Own Id: OTP-7305 Aux Id: seq10945

Ssh 1.0

Fixed Bugs and Malfunctions

Removed some special handling of prompts that made ssh behave differently than openssh.
Own Id: OTP-7485 Aux Id: seq11025
Bug in encoding of pty opts has been fixed.
Own Id: OTP-7504

Improvements and New Features

The architecture of the ssh processes has been reconstructed to fit in a supervision tree as to become a real OTP application and benefit from this when starting and stopping.
Own Id: OTP-7356 Aux Id: seq10899
Support for pty option echo off added. Requires kernel from R12B-4.
* POTENTIAL INCOMPATIBILITY *
Own Id: OTP-7502 Aux Id: seq10959
The ssh API has been enhanced a lot of old API functions has become deprecated.
Own Id: OTP-7503

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