Import OpenSSH 9.5 (Last was OpenSSH 9.3)

OpenSSH 9.5/9.5p1 (2023-10-04)
OpenSSH 9.5 was released on 2023-10-04. It is available from the
mirrors listed at https://www.openssh.com/.
OpenSSH is a 100% complete SSH protocol 2.0 implementation and
includes sftp client and server support.

Once again, we would like to thank the OpenSSH community for their
continued support of the project, especially those who contributed
code or patches, reported bugs, tested snapshots or donated to the
project. More information on donations may be found at:
https://www.openssh.com/donations.html

Changes since OpenSSH 9.4
=========================

This release fixes a number of bugs and adds some small features.

Potentially incompatible changes
--------------------------------

 * ssh-keygen(1): generate Ed25519 keys by default. Ed25519 public keys
   are very convenient due to their small size. Ed25519 keys are
   specified in RFC 8709 and OpenSSH has supported them since version 6.5
   (January 2014).

 * sshd(8): the Subsystem directive now accurately preserves quoting of
   subsystem commands and arguments. This may change behaviour for exotic
   configurations, but the most common subsystem configuration
   (sftp-server) is unlikely to be affected.

New features
------------

 * ssh(1): add keystroke timing obfuscation to the client. This attempts
   to hide inter-keystroke timings by sending interactive traffic at
   fixed intervals (default: every 20ms) when there is only a small
   amount of data being sent. It also sends fake "chaff" keystrokes for
   a random interval after the last real keystroke. These are
   controlled by a new ssh_config ObscureKeystrokeTiming keyword.

 * ssh(1), sshd(8): Introduce a transport-level ping facility. This adds
   a pair of SSH transport protocol messages SSH2_MSG_PING/PONG to
   implement a ping capability. These messages use numbers in the "local
   extensions" number space and are advertised using a "ping@openssh.com"
   ext-info message with a string version number of "0".

 * sshd(8): allow override of Subsystem directives in sshd Match blocks.

Bugfixes
--------

 * scp(1): fix scp in SFTP mode recursive upload and download of
   directories that contain symlinks to other directories. In scp mode,
   the links would be followed, but in SFTP mode they were not. bz3611

 * ssh-keygen(1): handle cr+lf (instead of just cr) line endings in
   sshsig signature files.

 * ssh(1): interactive mode for ControlPersist sessions if they
   originally requested a tty.

 * sshd(8): make PerSourceMaxStartups first-match-wins

 * sshd(8): limit artificial login delay to a reasonable maximum (5s)
   and don't delay at all for the "none" authentication mechanism.cw
    bz3602

 * sshd(8): Log errors in kex_exchange_identification() with level
   verbose instead of error to reduce preauth log spam. All of those
   get logged with a more generic error message by sshpkt_fatal().

 * sshd(8): correct math for ClientAliveInterval that caused the probes
    to be sent less frequently than configured.

 * ssh(1): fix regression in OpenSSH 9.4 (mux.c r1.99) that caused
   multiplexed sessions to ignore SIGINT under some circumstances.

Portability
-----------

 * Avoid clang zero-call-used-regs=all bug on Apple compilers, which
   for some reason have version numbers that do not match the upstream
   clang version numbers. bz#3584

 * Fix configure test for zlib 1.3 and later/development versions. bz3604

Checksums:
==========

 - SHA1 (openssh-9.5.tar.gz) = 8a0bd3a91fac338d97d91817af58df731f6509a3
 - SHA256 (openssh-9.5.tar.gz) = sVMxeM3d6g65qBMktJIofxmK4Ipg9dblKif0VnhPeO0=

 - SHA1 (openssh-9.5p1.tar.gz) = 35c16dcc6e7d0a9465faa241476ef24f76b196cc
 - SHA256 (openssh-9.5p1.tar.gz) = 8Cbnt5un+1QPdRgq+W3IqPHbOV+SK7yfbKYDZyaGCGs=

Please note that the SHA256 signatures are base64 encoded and not
hexadecimal (which is the default for most checksum tools). The PGP
key used to sign the releases is available from the mirror sites:
https://cdn.openbsd.org/pub/OpenBSD/OpenSSH/RELEASE_KEY.asc

Reporting Bugs:
===============

- Please read https://www.openssh.com/report.html
  Security bugs should be reported directly to openssh@openssh.com
OpenSSH 9.4/9.4p1 (2023-08-10)
OpenSSH 9.4 was released on 2023-08-10. It is available from the
mirrors listed at https://www.openssh.com/.
OpenSSH is a 100% complete SSH protocol 2.0 implementation and
includes sftp client and server support.

Once again, we would like to thank the OpenSSH community for their
continued support of the project, especially those who contributed
code or patches, reported bugs, tested snapshots or donated to the
project. More information on donations may be found at:
https://www.openssh.com/donations.html

Changes since OpenSSH 9.3p2
===========================

This release fixes a number of bugs and adds some small features.

Potentially incompatible changes
--------------------------------

 * This release removes support for older versions of libcrypto.
   OpenSSH now requires LibreSSL >= 3.1.0 or OpenSSL >= 1.1.1.
   Note that these versions are already deprecated by their upstream
   vendors.

 * ssh-agent(1): PKCS#11 modules must now be specified by their full
   paths. Previously dlopen(3) could search for them in system
   library directories.

New features
------------

 * ssh(1): allow forwarding Unix Domain sockets via ssh -W.

 * ssh(1): add support for configuration tags to ssh(1).
   This adds a ssh_config(5) "Tag" directive and corresponding
   "Match tag" predicate that may be used to select blocks of
   configuration similar to the pf.conf(5) keywords of the same
   name.

 * ssh(1): add a "match localnetwork" predicate. This allows matching
   on the addresses of available network interfaces and may be used to
   vary the effective client configuration based on network location.

 * ssh(1), sshd(8), ssh-keygen(1): infrastructure support for KRL
   extensions.  This defines wire formats for optional KRL extensions
   and implements parsing of the new submessages. No actual extensions
   are supported at this point.

 * sshd(8): AuthorizedPrincipalsCommand and AuthorizedKeysCommand now
   accept two additional %-expansion sequences: %D which expands to
   the routing domain of the connected session and %C which expands
   to the addresses and port numbers for the source and destination
   of the connection.

 * ssh-keygen(1): increase the default work factor (rounds) for the
   bcrypt KDF used to derive symmetric encryption keys for passphrase
   protected key files by 50%.

Bugfixes
--------

 * ssh-agent(1): improve isolation between loaded PKCS#11 modules
   by running separate ssh-pkcs11-helpers for each loaded provider.

 * ssh(1): make -f (fork after authentication) work correctly with
   multiplexed connections, including ControlPersist. bz3589 bz3589

 * ssh(1): make ConnectTimeout apply to multiplexing sockets and not
   just to network connections.

 * ssh-agent(1), ssh(1): improve defences against invalid PKCS#11
   modules being loaded by checking that the requested module
   contains the required symbol before loading it.

 * sshd(8): fix AuthorizedPrincipalsCommand when AuthorizedKeysCommand
   appears before it in sshd_config. Since OpenSSH 8.7 the
   AuthorizedPrincipalsCommand directive was incorrectly ignored in
   this situation. bz3574

 * sshd(8), ssh(1), ssh-keygen(1): remove vestigal support for KRL
   signatures When the KRL format was originally defined, it included
   support for signing of KRL objects. However, the code to sign KRLs
   and verify KRL signatues was never completed in OpenSSH. This
   release removes the partially-implemented code to verify KRLs.
   All OpenSSH tools now ignore KRL_SECTION_SIGNATURE sections in
   KRL files.

 * All: fix a number of memory leaks and unreachable/harmless integer
   overflows.

 * ssh-agent(1), ssh(1): don't truncate strings logged from PKCS#11
   modules; GHPR406

 * sshd(8), ssh(1): better validate CASignatureAlgorithms in
   ssh_config and sshd_config. Previously this directive would accept
   certificate algorithm names, but these were unusable in practice as
   OpenSSH does not support CA chains. bz3577

 * ssh(1): make `ssh -Q CASignatureAlgorithms` only list signature
   algorithms that are valid for CA signing. Previous behaviour was
   to list all signing algorithms, including certificate algorithms.

 * ssh-keyscan(1): gracefully handle systems where rlimits or the
   maximum number of open files is larger than INT_MAX; bz3581

 * ssh-keygen(1): fix "no comment" not showing on when running
   `ssh-keygen -l` on multiple keys where one has a comment and other
   following keys do not. bz3580

 * scp(1), sftp(1): adjust ftruncate() logic to handle servers that
   reorder requests. Previously, if the server reordered requests then
   the resultant file would be erroneously truncated.

 * ssh(1): don't incorrectly disable hostname canonicalization when
   CanonicalizeHostname=yes and ProxyJump was expicitly set to
   "none". bz3567

 * scp(1): when copying local->remote, check that the source file
   exists before opening an SFTP connection to the server. Based on
   GHPR#370

Portability
-----------

 * All: a number of build fixes for various platforms and
   configuration combinations.

 * sshd(8): provide a replacement for the SELinux matchpathcon()
   function, which is deprecated.

 * All: relax libcrypto version checks for OpenSSL >=3. Beyond
   OpenSSL 3.0, the ABI compatibility guarantees are wider (only
   the library major must match instead of major and minor in
   earlier versions).  bz#3548.

 * Tests: fix build problems for the sk-dummy.so FIDO provider module
   used in some tests.

Checksums:
==========

 - SHA1 (openssh-9.4.tar.gz) = d88126d8d7b8e5bf4656587ac4a16055560641cc
 - SHA256 (openssh-9.4.tar.gz) = 7eqFjx2hAunw+1Jy7f1JQXq//3AMr9B3dKtASDtq8go=

 - SHA1 (openssh-9.4p1.tar.gz) = 5dea1f3c88f9cfe53a711a3c893ee8b7d3ffecff
 - SHA256 (openssh-9.4p1.tar.gz) = Ngj9kIjbIWPOs+YAyFq3nQ3j0iHlkZLqGSPiMmOGaoU=

Please note that the SHA256 signatures are base64 encoded and not
hexadecimal (which is the default for most checksum tools). The PGP
key used to sign the releases is available from the mirror sites:
https://cdn.openbsd.org/pub/OpenBSD/OpenSSH/RELEASE_KEY.asc

Reporting Bugs:
===============

- Please read https://www.openssh.com/report.html
  Security bugs should be reported directly to openssh@openssh.com

crypto/external/bsd/openssh/dist/PROTOCOL.krl

@@ -37,6 +37,7 @@ The available section types are:
 #define KRL_SECTION_FINGERPRINT_SHA1		3
 #define KRL_SECTION_SIGNATURE			4
 #define KRL_SECTION_FINGERPRINT_SHA256		5
+#define KRL_SECTION_EXTENSION			255
 
 2. Certificate section
 
@@ -64,6 +65,7 @@ The certificate section types are:
 #define KRL_SECTION_CERT_SERIAL_RANGE	0x21
 #define KRL_SECTION_CERT_SERIAL_BITMAP	0x22
 #define KRL_SECTION_CERT_KEY_ID		0x23
+#define KRL_SECTION_CERT_EXTENSION	0x39
 
 2.1 Certificate serial list section
 
@@ -114,6 +116,29 @@ associated with a particular identity, e.g. a host or a user.
 This section must contain at least one "key_id". This section may appear
 multiple times.
 
+2.5. Certificate Extension subsections
+
+This subsection type provides a generic extension mechanism to the
+certificates KRL section that may be used to provide optional or critical
+data.
+
+Extensions are stored in subsections of type
+KRL_SECTION_CERT_EXTENSION with the following contents:
+
+	string	extension_name
+	boolean is_critical
+	string	extension_contents.
+
+Where "extension_name" describes the type of extension. It is
+recommended that user extensions follow "cert-name@domain.org" naming.
+
+The "is_critical" indicates whether this extension is mandatory or
+optional. If true, then any unsupported extension encountered should
+result in KRL parsing failure. If false, then it may be safely be
+ignored.
+
+The "extension_contents" contains the body of the extension.
+
 3. Explicit key sections
 
 These sections, identified as KRL_SECTION_EXPLICIT_KEY, revoke keys
@@ -144,7 +169,33 @@ as a big-endian integer.
 
 This section may appear multiple times.
 
-5. KRL signature sections
+5. Extension sections
+
+This section type provides a generic extension mechanism to the KRL
+format that may be used to provide optional or critical data.
+
+Extensions are recorded in sections of type KRL_SECTION_EXTENSION
+with the following contents:
+
+	string	extension_name
+	boolean is_critical
+	string	extension_contents.
+
+Where "extension_name" describes the type of extension. It is
+recommended that user extensions follow "name@domain.org" naming.
+
+The "is_critical" indicates whether this extension is mandatory or
+optional. If true, then any unsupported extension encountered should
+result in KRL parsing failure. If false, then it may be safely be
+ignored.
+
+The "extension_contents" contains the body of the extension.
+
+6. KRL signature sections
+
+Note: KRL signatures are not supported by OpenSSH. OpenSSH >= 9.4 will
+refuse to load KRLs that contain signatures. We recommend the use
+of SSHSIG (`ssh-keygen -Y sign ...`) style signatures for KRLs instead.
 
 The KRL_SECTION_SIGNATURE section serves a different purpose to the
 preceding ones: to provide cryptographic authentication of a KRL that
@@ -168,4 +219,4 @@ Implementations that retrieve KRLs over untrusted channels must verify
 signatures. Signature sections are optional for KRLs distributed by
 trusted means.
 
-$OpenBSD: PROTOCOL.krl,v 1.5 2018/09/12 01:21:34 djm Exp $
+$OpenBSD: PROTOCOL.krl,v 1.7 2023/07/17 04:01:10 djm Exp $