### Major changes between OpenSSL 3.0.7 and OpenSSL 3.0.8 [7 Feb 2023]
* Fixed NULL dereference during PKCS7 data verification ([CVE-2023-0401])
* Fixed X.400 address type confusion in X.509 GeneralName ([CVE-2023-0286])
* Fixed NULL dereference validating DSA public key ([CVE-2023-0217])
* Fixed Invalid pointer dereference in d2i_PKCS7 functions ([CVE-2023-0216])
* Fixed Use-after-free following BIO_new_NDEF ([CVE-2023-0215])
* Fixed Double free after calling PEM_read_bio_ex ([CVE-2022-4450])
* Fixed Timing Oracle in RSA Decryption ([CVE-2022-4304])
* Fixed X.509 Name Constraints Read Buffer Overflow ([CVE-2022-4203])
* Fixed X.509 Policy Constraints Double Locking ([CVE-2022-3996])
### Major changes between OpenSSL 3.0.6 and OpenSSL 3.0.7 [1 Nov 2022]
* Added RIPEMD160 to the default provider.
* Fixed regressions introduced in 3.0.6 version.
* Fixed two buffer overflows in punycode decoding functions.
([CVE-2022-3786]) and ([CVE-2022-3602])
### Major changes between OpenSSL 3.0.5 and OpenSSL 3.0.6 [11 Oct 2022]
* Fix for custom ciphers to prevent accidental use of NULL encryption
([CVE-2022-3358])
### Major changes between OpenSSL 3.0.4 and OpenSSL 3.0.5 [5 Jul 2022]
* Fixed heap memory corruption with RSA private key operation
([CVE-2022-2274])
* Fixed AES OCB failure to encrypt some bytes on 32-bit x86 platforms
([CVE-2022-2097])
### Major changes between OpenSSL 3.0.3 and OpenSSL 3.0.4 [21 Jun 2022]
* Fixed additional bugs in the c_rehash script which was not properly
sanitising shell metacharacters to prevent command injection
([CVE-2022-2068])
### Major changes between OpenSSL 3.0.2 and OpenSSL 3.0.3 [3 May 2022]
* Fixed a bug in the c_rehash script which was not properly sanitising shell
metacharacters to prevent command injection ([CVE-2022-1292])
* Fixed a bug in the function `OCSP_basic_verify` that verifies the signer
certificate on an OCSP response ([CVE-2022-1343])
* Fixed a bug where the RC4-MD5 ciphersuite incorrectly used the
AAD data as the MAC key ([CVE-2022-1434])
* Fix a bug in the OPENSSL_LH_flush() function that breaks reuse of the memory
occuppied by the removed hash table entries ([CVE-2022-1473])
### Major changes between OpenSSL 3.0.1 and OpenSSL 3.0.2 [15 Mar 2022]
* Fixed a bug in the BN_mod_sqrt() function that can cause it to loop forever
for non-prime moduli ([CVE-2022-0778])
### Major changes between OpenSSL 3.0.0 and OpenSSL 3.0.1 [14 Dec 2021]
* Fixed invalid handling of X509_verify_cert() internal errors in libssl
([CVE-2021-4044])
* Allow fetching an operation from the provider that owns an unexportable key
as a fallback if that is still allowed by the property query.
### Major changes between OpenSSL 1.1.1 and OpenSSL 3.0.0 [7 sep 2021]
* Enhanced 'openssl list' with many new options.
* Added migration guide to man7.
* Implemented support for fully "pluggable" TLSv1.3 groups.
* Added suport for Kernel TLS (KTLS).
* Changed the license to the Apache License v2.0.
* Moved all variations of the EVP ciphers CAST5, BF, IDEA, SEED, RC2,
RC4, RC5, and DES to the legacy provider.
* Moved the EVP digests MD2, MD4, MDC2, WHIRLPOOL and RIPEMD-160 to the legacy
provider.
* Added convenience functions for generating asymmetric key pairs.
* Deprecated the `OCSP_REQ_CTX` type and functions.
* Deprecated the `EC_KEY` and `EC_KEY_METHOD` types and functions.
* Deprecated the `RSA` and `RSA_METHOD` types and functions.
* Deprecated the `DSA` and `DSA_METHOD` types and functions.
* Deprecated the `DH` and `DH_METHOD` types and functions.
* Deprecated the `ERR_load_` functions.
* Remove the `RAND_DRBG` API.
* Deprecated the `ENGINE` API.
* Added `OSSL_LIB_CTX`, a libcrypto library context.
* Added various `_ex` functions to the OpenSSL API that support using
a non-default `OSSL_LIB_CTX`.
* Interactive mode is removed from the 'openssl' program.
* The X25519, X448, Ed25519, Ed448, SHAKE128 and SHAKE256 algorithms are
included in the FIPS provider.
* X509 certificates signed using SHA1 are no longer allowed at security
level 1 or higher. The default security level for TLS is 1, so
certificates signed using SHA1 are by default no longer trusted to
authenticate servers or clients.
* enable-crypto-mdebug and enable-crypto-mdebug-backtrace were mostly
disabled; the project uses address sanitize/leak-detect instead.
* Added a Certificate Management Protocol (CMP, RFC 4210) implementation
also covering CRMF (RFC 4211) and HTTP transfer (RFC 6712).
It is part of the crypto lib and adds a 'cmp' app with a demo configuration.
All widely used CMP features are supported for both clients and servers.
* Added a proper HTTP client supporting GET with optional redirection, POST,
arbitrary request and response content types, TLS, persistent connections,
connections via HTTP(s) proxies, connections and exchange via user-defined
BIOs (allowing implicit connections), and timeout checks.
* Added util/check-format.pl for checking adherence to the coding guidelines.
* Added OSSL_ENCODER, a generic encoder API.
* Added OSSL_DECODER, a generic decoder API.
* Added OSSL_PARAM_BLD, an easier to use API to OSSL_PARAM.
* Added error raising macros, ERR_raise() and ERR_raise_data().
* Deprecated ERR_put_error(), ERR_get_error_line(), ERR_get_error_line_data(),
ERR_peek_error_line_data(), ERR_peek_last_error_line_data() and
ERR_func_error_string().
* Added OSSL_PROVIDER_available(), to check provider availibility.
* Added 'openssl mac' that uses the EVP_MAC API.
* Added 'openssl kdf' that uses the EVP_KDF API.
* Add OPENSSL_info() and 'openssl info' to get built-in data.
* Add support for enabling instrumentation through trace and debug
output.
* Changed our version number scheme and set the next major release to
3.0.0
* Added EVP_MAC, an EVP layer MAC API, and a generic EVP_PKEY to EVP_MAC
bridge. Supported MACs are: BLAKE2, CMAC, GMAC, HMAC, KMAC, POLY1305
and SIPHASH.
* Removed the heartbeat message in DTLS feature.
* Added EVP_KDF, an EVP layer KDF and PRF API, and a generic EVP_PKEY to
EVP_KDF bridge. Supported KDFs are: HKDF, KBKDF, KRB5 KDF, PBKDF2,
PKCS12 KDF, SCRYPT, SSH KDF, SSKDF, TLS1 PRF, X9.42 KDF and X9.63 KDF.
* All of the low-level MD2, MD4, MD5, MDC2, RIPEMD160, SHA1, SHA224,
SHA256, SHA384, SHA512 and Whirlpool digest functions have been
deprecated.
* All of the low-level AES, Blowfish, Camellia, CAST, DES, IDEA, RC2,
RC4, RC5 and SEED cipher functions have been deprecated.
* All of the low-level DH, DSA, ECDH, ECDSA and RSA public key functions
have been deprecated.
* SSL 3, TLS 1.0, TLS 1.1, and DTLS 1.0 only work at security level 0,
except when RSA key exchange without SHA1 is used.
* Added providers, a new pluggability concept that will replace the
ENGINE API and ENGINE implementations.
OpenSSL 1.1.1
-------------
### Major changes between OpenSSL 1.1.1k and OpenSSL 1.1.1l [24 Aug 2021]
* Fixed an SM2 Decryption Buffer Overflow ([CVE-2021-3711])
* Fixed various read buffer overruns processing ASN.1 strings ([CVE-2021-3712])
### Major changes between OpenSSL 1.1.1j and OpenSSL 1.1.1k [25 Mar 2021]
* Fixed a problem with verifying a certificate chain when using the
X509_V_FLAG_X509_STRICT flag ([CVE-2021-3450])
* Fixed an issue where an OpenSSL TLS server may crash if sent a maliciously
crafted renegotiation ClientHello message from a client ([CVE-2021-3449])
### Major changes between OpenSSL 1.1.1i and OpenSSL 1.1.1j [16 Feb 2021]
* Fixed a NULL pointer deref in the X509_issuer_and_serial_hash()
function ([CVE-2021-23841])
* Fixed the RSA_padding_check_SSLv23() function and the RSA_SSLV23_PADDING
padding mode to correctly check for rollback attacks
* Fixed an overflow in the EVP_CipherUpdate, EVP_EncryptUpdate and
EVP_DecryptUpdate functions ([CVE-2021-23840])
* Fixed SRP_Calc_client_key so that it runs in constant time
### Major changes between OpenSSL 1.1.1h and OpenSSL 1.1.1i [8 Dec 2020]
* Fixed NULL pointer deref in GENERAL_NAME_cmp ([CVE-2020-1971])
### Major changes between OpenSSL 1.1.1g and OpenSSL 1.1.1h [22 Sep 2020]
* Disallow explicit curve parameters in verifications chains when
X509_V_FLAG_X509_STRICT is used
* Enable 'MinProtocol' and 'MaxProtocol' to configure both TLS and DTLS
contexts
* Oracle Developer Studio will start reporting deprecation warnings
### Major changes between OpenSSL 1.1.1f and OpenSSL 1.1.1g [21 Apr 2020]
* Fixed segmentation fault in SSL_check_chain() ([CVE-2020-1967])
### Major changes between OpenSSL 1.1.1e and OpenSSL 1.1.1f [31 Mar 2020]
* Revert the unexpected EOF reporting via SSL_ERROR_SSL
### Major changes between OpenSSL 1.1.1d and OpenSSL 1.1.1e [17 Mar 2020]
* Fixed an overflow bug in the x64_64 Montgomery squaring procedure
used in exponentiation with 512-bit moduli ([CVE-2019-1551])
### Major changes between OpenSSL 1.1.1c and OpenSSL 1.1.1d [10 Sep 2019]
* Fixed a fork protection issue ([CVE-2019-1549])
* Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey
([CVE-2019-1563])
* For built-in EC curves, ensure an EC_GROUP built from the curve name is
used even when parsing explicit parameters
* Compute ECC cofactors if not provided during EC_GROUP construction
([CVE-2019-1547])
* Early start up entropy quality from the DEVRANDOM seed source has been
improved for older Linux systems
* Correct the extended master secret constant on EBCDIC systems
* Use Windows installation paths in the mingw builds ([CVE-2019-1552])
* Changed DH_check to accept parameters with order q and 2q subgroups
* Significantly reduce secure memory usage by the randomness pools
* Revert the DEVRANDOM_WAIT feature for Linux systems
### Major changes between OpenSSL 1.1.1b and OpenSSL 1.1.1c [28 May 2019]
* Prevent over long nonces in ChaCha20-Poly1305 ([CVE-2019-1543])
### Major changes between OpenSSL 1.1.1a and OpenSSL 1.1.1b [26 Feb 2019]
* Change the info callback signals for the start and end of a post-handshake
message exchange in TLSv1.3.
* Fix a bug in DTLS over SCTP. This breaks interoperability with older
versions of OpenSSL like OpenSSL 1.1.0 and OpenSSL 1.0.2.
### Major changes between OpenSSL 1.1.1 and OpenSSL 1.1.1a [20 Nov 2018]
* Timing vulnerability in DSA signature generation ([CVE-2018-0734])
* Timing vulnerability in ECDSA signature generation ([CVE-2018-0735])
### Major changes between OpenSSL 1.1.0i and OpenSSL 1.1.1 [11 Sep 2018]
* Support for TLSv1.3 added. The TLSv1.3 implementation includes:
* Fully compliant implementation of RFC8446 (TLSv1.3) on by default
* Early data (0-RTT)
* Post-handshake authentication and key update
* Middlebox Compatibility Mode
* TLSv1.3 PSKs
* Support for all five RFC8446 ciphersuites
* RSA-PSS signature algorithms (backported to TLSv1.2)
* Configurable session ticket support
* Stateless server support
* Rewrite of the packet construction code for "safer" packet handling
* Rewrite of the extension handling code
For further important information, see the [TLS1.3 page](
https://wiki.openssl.org/index.php/TLS1.3) in the OpenSSL Wiki.
* Complete rewrite of the OpenSSL random number generator to introduce the
following capabilities
* The default RAND method now utilizes an AES-CTR DRBG according to
NIST standard SP 800-90Ar1.
* Support for multiple DRBG instances with seed chaining.
* There is a public and private DRBG instance.
* The DRBG instances are fork-safe.
* Keep all global DRBG instances on the secure heap if it is enabled.
* The public and private DRBG instance are per thread for lock free
operation
* Support for various new cryptographic algorithms including:
* SHA3
* SHA512/224 and SHA512/256
* EdDSA (both Ed25519 and Ed448) including X509 and TLS support
* X448 (adding to the existing X25519 support in 1.1.0)
* Multi-prime RSA
* SM2
* SM3
* SM4
* SipHash
* ARIA (including TLS support)
* Significant Side-Channel attack security improvements
* Add a new ClientHello callback to provide the ability to adjust the SSL
object at an early stage.
* Add 'Maximum Fragment Length' TLS extension negotiation and support
* A new STORE module, which implements a uniform and URI based reader of
stores that can contain keys, certificates, CRLs and numerous other
objects.
* Move the display of configuration data to configdata.pm.
* Allow GNU style "make variables" to be used with Configure.
* Claim the namespaces OSSL and OPENSSL, represented as symbol prefixes
* Rewrite of devcrypto engine
May be helpful explanation but it didn't make its way upstream,
whereas the file has moved and had other upstream changes, so let's
make the next merge less painful.
No functional change intended.
Upstream OpenSSL changed
loop 1b
to
dec %rcx
jnz 1b
which has mostly the same semantics, in this change:
https://github.com/openssl/openssl/pull/4743
For some reason, in one of the OpenSSL updates, we ended up with a
local change to revert this.
The Intel and AMD optimization guides are silent on the LOOP
instruction, but Agner Fog's tables shows that while LOOP is one
cycle shorter than DEC;JNZ on AMD Zen microarchitectures, it is a
good half dozen cycles longer than DEC;JNZ on recent Intel
microarchitectures.
The history of the OpenSSL change suggests it was intended, and I
can't find any indication other than `merge conflicts' that we
intended to keep the LOOP version. So let's reduce the local diff by
nixing it.
Cute as it is to write the an instruction in a delay slot with an
extra space, it's not really useful to keep this around as a local
change since the substantive change was applied upstream years ago.
Much as I'm happy to eliminate sprintf, there's very little value to
maintaining a local change under an #ifdef that will never, ever be
taken on NetBSD.
Verified libcrypto.so does not sprout any references to sprintf as a
result.
This was needed back when the file was patched locally to cast a
pointer to intptr_t rather than to int, but that code is now gone and
the include is no longer necessary. So let's reduce the local diff
by omitting this unnecessary change.
According to the commit history, this was introduced when gcc4.5
complained about using the return value of fileno without checking it
against -1. gcc 10.4 no longer appears to object, so let's just nix
the local patch.
Changes between 1.1.1s and 1.1.1t [7 Feb 2023]
*) Fixed X.400 address type confusion in X.509 GeneralName.
There is a type confusion vulnerability relating to X.400 address processing
inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING
but subsequently interpreted by GENERAL_NAME_cmp as an ASN1_TYPE. This
vulnerability may allow an attacker who can provide a certificate chain and
CRL (neither of which need have a valid signature) to pass arbitrary
pointers to a memcmp call, creating a possible read primitive, subject to
some constraints. Refer to the advisory for more information. Thanks to
David Benjamin for discovering this issue. (CVE-2023-0286)
This issue has been fixed by changing the public header file definition of
GENERAL_NAME so that x400Address reflects the implementation. It was not
possible for any existing application to successfully use the existing
definition; however, if any application references the x400Address field
(e.g. in dead code), note that the type of this field has changed. There is
no ABI change.
[Hugo Landau]
*) Fixed Use-after-free following BIO_new_NDEF.
The public API function BIO_new_NDEF is a helper function used for
streaming ASN.1 data via a BIO. It is primarily used internally to OpenSSL
to support the SMIME, CMS and PKCS7 streaming capabilities, but may also
be called directly by end user applications.
The function receives a BIO from the caller, prepends a new BIO_f_asn1
filter BIO onto the front of it to form a BIO chain, and then returns
the new head of the BIO chain to the caller. Under certain conditions,
for example if a CMS recipient public key is invalid, the new filter BIO
is freed and the function returns a NULL result indicating a failure.
However, in this case, the BIO chain is not properly cleaned up and the
BIO passed by the caller still retains internal pointers to the previously
freed filter BIO. If the caller then goes on to call BIO_pop() on the BIO
then a use-after-free will occur. This will most likely result in a crash.
(CVE-2023-0215)
[Viktor Dukhovni, Matt Caswell]
*) Fixed Double free after calling PEM_read_bio_ex.
The function PEM_read_bio_ex() reads a PEM file from a BIO and parses and
decodes the "name" (e.g. "CERTIFICATE"), any header data and the payload
data. If the function succeeds then the "name_out", "header" and "data"
arguments are populated with pointers to buffers containing the relevant
decoded data. The caller is responsible for freeing those buffers. It is
possible to construct a PEM file that results in 0 bytes of payload data.
In this case PEM_read_bio_ex() will return a failure code but will populate
the header argument with a pointer to a buffer that has already been freed.
If the caller also frees this buffer then a double free will occur. This
will most likely lead to a crash.
The functions PEM_read_bio() and PEM_read() are simple wrappers around
PEM_read_bio_ex() and therefore these functions are also directly affected.
These functions are also called indirectly by a number of other OpenSSL
functions including PEM_X509_INFO_read_bio_ex() and
SSL_CTX_use_serverinfo_file() which are also vulnerable. Some OpenSSL
internal uses of these functions are not vulnerable because the caller does
not free the header argument if PEM_read_bio_ex() returns a failure code.
(CVE-2022-4450)
[Kurt Roeckx, Matt Caswell]
*) Fixed Timing Oracle in RSA Decryption.
A timing based side channel exists in the OpenSSL RSA Decryption
implementation which could be sufficient to recover a plaintext across
a network in a Bleichenbacher style attack. To achieve a successful
decryption an attacker would have to be able to send a very large number
of trial messages for decryption. The vulnerability affects all RSA padding
modes: PKCS#1 v1.5, RSA-OEAP and RSASVE.
(CVE-2022-4304)
[Dmitry Belyavsky, Hubert Kario]
Changes between 1.1.1r and 1.1.1s [1 Nov 2022]
*) Fixed a regression introduced in 1.1.1r version not refreshing the
certificate data to be signed before signing the certificate.
[Gibeom Gwon]
Changes between 1.1.1q and 1.1.1r [11 Oct 2022]
*) Fixed the linux-mips64 Configure target which was missing the
SIXTY_FOUR_BIT bn_ops flag. This was causing heap corruption on that
platform.
[Adam Joseph]
*) Fixed a strict aliasing problem in bn_nist. Clang-14 optimisation was
causing incorrect results in some cases as a result.
[Paul Dale]
*) Fixed SSL_pending() and SSL_has_pending() with DTLS which were failing to
report correct results in some cases
[Matt Caswell]
*) Fixed a regression introduced in 1.1.1o for re-signing certificates with
different key sizes
[Todd Short]
*) Added the loongarch64 target
[Shi Pujin]
*) Fixed a DRBG seed propagation thread safety issue
[Bernd Edlinger]
*) Fixed a memory leak in tls13_generate_secret
[Bernd Edlinger]
*) Fixed reported performance degradation on aarch64. Restored the
implementation prior to commit 2621751 ("aes/asm/aesv8-armx.pl: avoid
32-bit lane assignment in CTR mode") for 64bit targets only, since it is
reportedly 2-17% slower and the silicon errata only affects 32bit targets.
The new algorithm is still used for 32 bit targets.
[Bernd Edlinger]
*) Added a missing header for memcmp that caused compilation failure on some
platforms
[Gregor Jasny]
Changes between 1.1.1p and 1.1.1q [5 Jul 2022]
*) AES OCB mode for 32-bit x86 platforms using the AES-NI assembly optimised
implementation would not encrypt the entirety of the data under some
circumstances. This could reveal sixteen bytes of data that was
preexisting in the memory that wasn't written. In the special case of
"in place" encryption, sixteen bytes of the plaintext would be revealed.
Since OpenSSL does not support OCB based cipher suites for TLS and DTLS,
they are both unaffected.
(CVE-2022-2097)
[Alex Chernyakhovsky, David Benjamin, Alejandro Sedeño]
Changes between 1.1.1o and 1.1.1p [21 Jun 2022]
*) In addition to the c_rehash shell command injection identified in
CVE-2022-1292, further bugs where the c_rehash script does not
properly sanitise shell metacharacters to prevent command injection have
been fixed.
When the CVE-2022-1292 was fixed it was not discovered that there
are other places in the script where the file names of certificates
being hashed were possibly passed to a command executed through the shell.
This script is distributed by some operating systems in a manner where
it is automatically executed. On such operating systems, an attacker
could execute arbitrary commands with the privileges of the script.
Use of the c_rehash script is considered obsolete and should be replaced
by the OpenSSL rehash command line tool.
(CVE-2022-2068)
[Daniel Fiala, Tomáš Mráz]
*) When OpenSSL TLS client is connecting without any supported elliptic
curves and TLS-1.3 protocol is disabled the connection will no longer fail
if a ciphersuite that does not use a key exchange based on elliptic
curves can be negotiated.
[Tomáš Mráz]
Changes between 1.1.1n and 1.1.1o [3 May 2022]
*) Fixed a bug in the c_rehash script which was not properly sanitising shell
metacharacters to prevent command injection. This script is distributed
by some operating systems in a manner where it is automatically executed.
On such operating systems, an attacker could execute arbitrary commands
with the privileges of the script.
Use of the c_rehash script is considered obsolete and should be replaced
by the OpenSSL rehash command line tool.
(CVE-2022-1292)
[Tomáš Mráz]
If rule_str ended in a "-", "l" was incremented one byte past the
end of the buffer. This resulted in an out-of-bounds read when "l"
is dereferenced at the end of the loop. It is safest to just return
early in this case since the condition occurs inside a nested loop.
This release is focused on bug fixing.
Security
========
This release contains fixes for three minor memory safety problems.
None are believed to be exploitable, but we report most memory safety
problems as potential security vulnerabilities out of caution.
* ssh-keyscan(1): fix a one-byte overflow in SSH- banner processing.
Reported by Qualys
* ssh-keygen(1): double free() in error path of file hashing step in
signing/verify code; GHPR333
* ssh-keysign(8): double-free in error path introduced in openssh-8.9
Potentially-incompatible changes
--------------------------------
* The portable OpenSSH project now signs commits and release tags
using git's recent SSH signature support. The list of developer
signing keys is included in the repository as .git_allowed_signers
and is cross-signed using the PGP key that is still used to sign
release artifacts:
https://cdn.openbsd.org/pub/OpenBSD/OpenSSH/RELEASE_KEY.asc
* ssh(1), sshd(8): SetEnv directives in ssh_config and sshd_config
are now first-match-wins to match other directives. Previously
if an environment variable was multiply specified the last set
value would have been used. bz3438
* ssh-keygen(8): ssh-keygen -A (generate all default host key types)
will no longer generate DSA keys, as these are insecure and have
not been used by default for some years.
New features
------------
* ssh(1), sshd(8): add a RequiredRSASize directive to set a minimum
RSA key length. Keys below this length will be ignored for user
authentication and for host authentication in sshd(8).
ssh(1) will terminate a connection if the server offers an RSA key
that falls below this limit, as the SSH protocol does not include
the ability to retry a failed key exchange.
* sftp-server(8): add a "users-groups-by-id@openssh.com" extension
request that allows the client to obtain user/group names that
correspond to a set of uids/gids.
* sftp(1): use "users-groups-by-id@openssh.com" sftp-server
extension (when available) to fill in user/group names for
directory listings.
* sftp-server(8): support the "home-directory" extension request
defined in draft-ietf-secsh-filexfer-extensions-00. This overlaps
a bit with the existing "expand-path@openssh.com", but some other
clients support it.
* ssh-keygen(1), sshd(8): allow certificate validity intervals,
sshsig verification times and authorized_keys expiry-time options
to accept dates in the UTC time zone in addition to the default
of interpreting them in the system time zone. YYYYMMDD and
YYMMDDHHMM[SS] dates/times will be interpreted as UTC if suffixed
with a 'Z' character.
Also allow certificate validity intervals to be specified in raw
seconds-since-epoch as hex value, e.g. -V 0x1234:0x4567890. This
is intended for use by regress tests and other tools that call
ssh-keygen as part of a CA workflow. bz3468
* sftp(1): allow arguments to the sftp -D option, e.g. sftp -D
"/usr/libexec/sftp-server -el debug3"
* ssh-keygen(1): allow the existing -U (use agent) flag to work
with "-Y sign" operations, where it will be interpreted to require
that the private keys is hosted in an agent; bz3429
Bugfixes
--------
* ssh-keygen(1): implement the "verify-required" certificate option.
This was already documented when support for user-verified FIDO
keys was added, but the ssh-keygen(1) code was missing.
* ssh-agent(1): hook up the restrict_websafe command-line flag;
previously the flag was accepted but never actually used.
* sftp(1): improve filename tab completions: never try to complete
names to non-existent commands, and better match the completion
type (local or remote filename) against the argument position
being completed.
* ssh-keygen(1), ssh(1), ssh-agent(1): several fixes to FIDO key
handling, especially relating to keys that request
user-verification. These should reduce the number of unnecessary
PIN prompts for keys that support intrinsic user verification.
GHPR302, GHPR329
* ssh-keygen(1): when enrolling a FIDO resident key, check if a
credential with matching application and user ID strings already
exists and, if so, prompt the user for confirmation before
overwriting the credential. GHPR329
* sshd(8): improve logging of errors when opening authorized_keys
files. bz2042
* ssh(1): avoid multiplexing operations that could cause SIGPIPE from
causing the client to exit early. bz3454
* ssh_config(5), sshd_config(5): clarify that the RekeyLimit
directive applies to both transmitted and received data. GHPR328
* ssh-keygen(1): avoid double fclose() in error path.
* sshd(8): log an error if pipe() fails while accepting a
connection. bz3447
* ssh(1), ssh-keygen(1): fix possible NULL deref when built without
FIDO support. bz3443
* ssh-keyscan(1): add missing *-sk types to ssh-keyscan manpage.
GHPR294.
* sshd(8): ensure that authentication passwords are cleared from
memory in error paths. GHPR286
* ssh(1), ssh-agent(1): avoid possibility of notifier code executing
kill(-1). GHPR286
* ssh_config(5): note that the ProxyJump directive also accepts the
same tokens as ProxyCommand. GHPR305.
* scp(1): do not not ftruncate(3) files early when in sftp mode. The
previous behaviour of unconditionally truncating the destination
file would cause "scp ~/foo localhost:foo" and the reverse
"scp localhost:foo ~/foo" to delete all the contents of their
destination. bz3431
* ssh-keygen(1): improve error message when 'ssh-keygen -Y sign' is
unable to load a private key; bz3429
* sftp(1), scp(1): when performing operations that glob(3) a remote
path, ensure that the implicit working directory used to construct
that path escapes glob(3) characters. This prevents glob characters
from being processed in places they shouldn't, e.g. "cd /tmp/a*/",
"get *.txt" should have the get operation treat the path "/tmp/a*"
literally and not attempt to expand it.
* ssh(1), sshd(8): be stricter in which characters will be accepted
in specifying a mask length; allow only 0-9. GHPR278
* ssh-keygen(1): avoid printing hash algorithm twice when dumping a
KRL
* ssh(1), sshd(8): continue running local I/O for open channels
during SSH transport rekeying. This should make ~-escapes work in
the client (e.g. to exit) if the connection happened to have
stalled during a rekey event.
* ssh(1), sshd(8): avoid potential poll() spin during rekeying
* Further hardening for sshbuf internals: disallow "reparenting" a
hierarchical sshbuf and zero the entire buffer if reallocation
fails. GHPR287
Portability
-----------
* ssh(1), ssh-keygen(1), sshd(8): automatically enable the built-in
FIDO security key support if libfido2 is found and usable, unless
--without-security-key-builtin was requested.
* ssh(1), ssh-keygen(1), sshd(8): many fixes to make the WinHello
FIDO device usable on Cygwin. The windows://hello FIDO device will
be automatically used by default on this platform unless requested
otherwise, or when probing resident FIDO credentials (an operation
not currently supported by WinHello).
* Portable OpenSSH: remove workarounds for obsolete and unsupported
versions of OpenSSL libcrypto. In particular, this release removes
fallback support for OpenSSL that lacks AES-CTR or AES-GCM.
Those AES cipher modes were added to OpenSSL prior to the minimum
version currently supported by OpenSSH, so this is not expected to
impact any currently supported configurations.
* sshd(8): fix SANDBOX_SECCOMP_FILTER_DEBUG on current Linux/glibc
* All: resync and clean up internal CSPRNG code.
* scp(1), sftp(1), sftp-server(8): avoid linking these programs with
unnecessary libraries. They are no longer linked against libz and
libcrypto. This may be of benefit to space constrained systems
using any of those components in isolation.
* sshd(8): add AUDIT_ARCH_PPC to supported seccomp sandbox
architectures.
* configure: remove special casing of crypt(). configure will no
longer search for crypt() in libcrypto, as it was removed from
there years ago. configure will now only search libc and libcrypt.
* configure: refuse to use OpenSSL 3.0.4 due to potential RCE in its
RSA implementation (CVE-2022-2274) on x86_64.
* All: request 1.1x API compatibility for OpenSSL >=3.x; GHPR322
* ssh(1), ssh-keygen(1), sshd(8): fix a number of missing includes
required by the XMSS code on some platforms.
* sshd(8): cache timezone data in capsicum sandbox.
error: passing 'char [1]' to parameter of type 'const uint8_t *'
(aka 'const unsigned char *') converts between pointers to integer
types where one is of the unique plain 'char' type and the other is
not [-Werror,-Wpointer-sign]
This way they match the mtree and make sense and don't cause editors
to ask to override read-only files when editing them.
Exception: Not sure /etc/bluetooth/protocols makes as much sense to
edit, but the mtree says 644, so if you want to change it, make sure
to change it in both places -- Makefile and mtree.
XXX pullup-8
XXX pullup-9
This avoids hundreds of lint warnings for OpenSSL's stack definitions:
openssl/x509.h(75): warning:
static function sk_X509_NAME_ENTRY_num unused [236]
Changes between 1.1.1m and 1.1.1n [15 Mar 2022]
*) Fixed a bug in the BN_mod_sqrt() function that can cause it to loop forever
for non-prime moduli.
Internally this function is used when parsing certificates that contain
elliptic curve public keys in compressed form or explicit elliptic curve
parameters with a base point encoded in compressed form.
It is possible to trigger the infinite loop by crafting a certificate that
has invalid explicit curve parameters.
Since certificate parsing happens prior to verification of the certificate
signature, any process that parses an externally supplied certificate may
thus be subject to a denial of service attack. The infinite loop can also
be reached when parsing crafted private keys as they can contain explicit
elliptic curve parameters.
Thus vulnerable situations include:
- TLS clients consuming server certificates
- TLS servers consuming client certificates
- Hosting providers taking certificates or private keys from customers
- Certificate authorities parsing certification requests from subscribers
- Anything else which parses ASN.1 elliptic curve parameters
Also any other applications that use the BN_mod_sqrt() where the attacker
can control the parameter values are vulnerable to this DoS issue.
(CVE-2022-0778)
[Tomáš Mráz]
*) Add ciphersuites based on DHE_PSK (RFC 4279) and ECDHE_PSK (RFC 5489)
to the list of ciphersuites providing Perfect Forward Secrecy as
required by SECLEVEL >= 3.
[Dmitry Belyavskiy, Nicola Tuveri]
Future deprecation notice
=========================
A near-future release of OpenSSH will switch scp(1) from using the
legacy scp/rcp protocol to using SFTP by default.
Legacy scp/rcp performs wildcard expansion of remote filenames (e.g.
"scp host:* .") through the remote shell. This has the side effect of
requiring double quoting of shell meta-characters in file names
included on scp(1) command-lines, otherwise they could be interpreted
as shell commands on the remote side.
This creates one area of potential incompatibility: scp(1) when using
the SFTP protocol no longer requires this finicky and brittle quoting,
and attempts to use it may cause transfers to fail. We consider the
removal of the need for double-quoting shell characters in file names
to be a benefit and do not intend to introduce bug-compatibility for
legacy scp/rcp in scp(1) when using the SFTP protocol.
Another area of potential incompatibility relates to the use of remote
paths relative to other user's home directories, for example -
"scp host:~user/file /tmp". The SFTP protocol has no native way to
expand a ~user path. However, sftp-server(8) in OpenSSH 8.7 and later
support a protocol extension "expand-path@openssh.com" to support
this.
Security Near Miss
==================
* sshd(8): fix an integer overflow in the user authentication path
that, in conjunction with other logic errors, could have yielded
unauthenticated access under difficult to exploit conditions.
This situation is not exploitable because of independent checks in
the privilege separation monitor. Privilege separation has been
enabled by default in since openssh-3.2.2 (released in 2002) and
has been mandatory since openssh-7.5 (released in 2017). Moreover,
portable OpenSSH has used toolchain features available in most
modern compilers to abort on signed integer overflow since
openssh-6.5 (released in 2014).
Thanks to Malcolm Stagg for finding and reporting this bug.
Potentially-incompatible changes
================================
* sshd(8), portable OpenSSH only: this release removes in-built
support for MD5-hashed passwords. If you require these on your
system then we recommend linking against libxcrypt or similar.
* This release modifies the FIDO security key middleware interface
and increments SSH_SK_VERSION_MAJOR.
Changes since OpenSSH 8.8
=========================
This release includes a number of new features.
New features
------------
* ssh(1), sshd(8), ssh-add(1), ssh-agent(1): add a system for
restricting forwarding and use of keys added to ssh-agent(1)
A detailed description of the feature is available at
https://www.openssh.com/agent-restrict.html and the protocol
extensions are documented in the PROTOCOL and PROTOCOL.agent
files in the source release.
* ssh(1), sshd(8): add the sntrup761x25519-sha512@openssh.com hybrid
ECDH/x25519 + Streamlined NTRU Prime post-quantum KEX to the
default KEXAlgorithms list (after the ECDH methods but before the
prime-group DH ones). The next release of OpenSSH is likely to
make this key exchange the default method.
* ssh-keygen(1): when downloading resident keys from a FIDO token,
pass back the user ID that was used when the key was created and
append it to the filename the key is written to (if it is not the
default). Avoids keys being clobbered if the user created multiple
resident keys with the same application string but different user
IDs.
* ssh-keygen(1), ssh(1), ssh-agent(1): better handling for FIDO keys
on tokens that provide user verification (UV) on the device itself,
including biometric keys, avoiding unnecessary PIN prompts.
* ssh-keygen(1): add "ssh-keygen -Y match-principals" operation to
perform matching of principals names against an allowed signers
file. To be used towards a TOFU model for SSH signatures in git.
* ssh-add(1), ssh-agent(1): allow pin-required FIDO keys to be added
to ssh-agent(1). $SSH_ASKPASS will be used to request the PIN at
authentication time.
* ssh-keygen(1): allow selection of hash at sshsig signing time
(either sha512 (default) or sha256).
* ssh(1), sshd(8): read network data directly to the packet input
buffer instead indirectly via a small stack buffer. Provides a
modest performance improvement.
* ssh(1), sshd(8): read data directly to the channel input buffer,
providing a similar modest performance improvement.
* ssh(1): extend the PubkeyAuthentication configuration directive to
accept yes|no|unbound|host-bound to allow control over one of the
protocol extensions used to implement agent-restricted keys.
Bugfixes
--------
* sshd(8): document that CASignatureAlgorithms, ExposeAuthInfo and
PubkeyAuthOptions can be used in a Match block. PR#277.
* sshd(8): fix possible string truncation when constructing paths to
.rhosts/.shosts files with very long user home directory names.
* ssh-keysign(1): unbreak for KEX algorithms that use SHA384/512
exchange hashes
* ssh(1): don't put the TTY into raw mode when SessionType=none,
avoids ^C being unable to kill such a session. bz3360
* scp(1): fix some corner-case bugs in SFTP-mode handling of
~-prefixed paths.
* ssh(1): unbreak hostbased auth using RSA keys. Allow ssh(1) to
select RSA keys when only RSA/SHA2 signature algorithms are
configured (this is the default case). Previously RSA keys were
not being considered in the default case.
* ssh-keysign(1): make ssh-keysign use the requested signature
algorithm and not the default for the key type. Part of unbreaking
hostbased auth for RSA/SHA2 keys.
* ssh(1): stricter UpdateHostkey signature verification logic on
the client- side. Require RSA/SHA2 signatures for RSA hostkeys
except when RSA/SHA1 was explicitly negotiated during initial
KEX; bz3375
* ssh(1), sshd(8): fix signature algorithm selection logic for
UpdateHostkeys on the server side. The previous code tried to
prefer RSA/SHA2 for hostkey proofs of RSA keys, but missed some
cases. This will use RSA/SHA2 signatures for RSA keys if the
client proposed these algorithms in initial KEX. bz3375
* All: convert all uses of select(2)/pselect(2) to poll(2)/ppoll(2).
This includes the mainloops in ssh(1), ssh-agent(1), ssh-agent(1)
and sftp-server(8), as well as the sshd(8) listen loop and all
other FD read/writability checks. On platforms with missing or
broken poll(2)/ppoll(2) syscalls a select(2)-based compat shim is
available.
* ssh-keygen(1): the "-Y find-principals" command was verifying key
validity when using ca certs but not with simple key lifetimes
within the allowed signers file.
* ssh-keygen(1): make sshsig verify-time argument parsing optional
* sshd(8): fix truncation in rhosts/shosts path construction.
* ssh(1), ssh-agent(1): avoid xmalloc(0) for PKCS#11 keyid for ECDSA
keys (we already did this for RSA keys). Avoids fatal errors for
PKCS#11 libraries that return empty keyid, e.g. Microchip ATECC608B
"cryptoauthlib"; bz#3364
* ssh(1), ssh-agent(1): improve the testing of credentials against
inserted FIDO: ask the token whether a particular key belongs to
it in cases where the token supports on-token user-verification
(e.g. biometrics) rather than just assuming that it will accept it.
Will reduce spurious "Confirm user presence" notifications for key
handles that relate to FIDO keys that are not currently inserted in at
least some cases. bz3366
* ssh(1), sshd(8): correct value for IPTOS_DSCP_LE. It needs to
allow for the preceding two ECN bits. bz#3373
* ssh-keygen(1): add missing -O option to usage() for the "-Y sign"
option.
* ssh-keygen(1): fix a NULL deref when using the find-principals
function, when matching an allowed_signers line that contains a
namespace restriction, but no restriction specified on the
command-line
* ssh-agent(1): fix memleak in process_extension(); oss-fuzz
issue #42719
* ssh(1): suppress "Connection to xxx closed" messages when LogLevel
is set to "error" or above. bz3378
* ssh(1), sshd(8): use correct zlib flags when inflate(3)-ing
compressed packet data. bz3372
* scp(1): when recursively transferring files in SFTP mode, create the
destination directory if it doesn't already exist to match scp(1) in
legacy RCP mode behaviour.
* scp(1): many improvements in error message consistency between scp(1)
in SFTP mode vs legacy RCP mode.
* sshd(8): fix potential race in SIGTERM handling PR#289
* ssh(1), ssh(8): since DSA keys are deprecated, move them to the
end of the default list of public keys so that they will be tried
last. PR#295
* ssh-keygen(1): allow 'ssh-keygen -Y find-principals' to match
wildcard principals in allowed_signers files
Portability
-----------
* ssh(1), sshd(8): don't trust closefrom(2) on Linux. glibc's
implementation does not work in a chroot when the kernel does not
have close_range(2). It tries to read from /proc/self/fd and when
that fails dies with an assertion of sorts. Instead, call
close_range(2) directly from our compat code and fall back if
that fails. bz#3349,
* OS X poll(2) is broken; use compat replacement. For character-
special devices like /dev/null, Darwin's poll(2) returns POLLNVAL
when polled with POLLIN. Apparently this is Apple bug 3710161 -
not public but a websearch will find other OSS projects
rediscovering it periodically since it was first identified in
2005.
* Correct handling of exceptfds/POLLPRI in our select(2)-based
poll(2)/ppoll(2) compat implementation.
* Cygwin: correct checking of mbstowcs() return value.
* Add a basic SECURITY.md that refers people to the openssh.com
website.
* Enable additional compiler warnings and toolchain hardening flags,
including -Wbitwise-instead-of-logical, -Wmisleading-indentation,
-fzero-call-used-regs and -ftrivial-auto-var-init.
* HP/UX. Use compat getline(3) on HP-UX 10.x, where the libc version
is not reliable.
*) Avoid loading of a dynamic engine twice.
[Bernd Edlinger]
*) Fixed building on Debian with kfreebsd kernels
[Mattias Ellert]
*) Prioritise DANE TLSA issuer certs over peer certs
[Viktor Dukhovni]
*) Fixed random API for MacOS prior to 10.12
These MacOS versions don't support the CommonCrypto APIs
[Lenny Primak]
Changes between 1.1.1k and 1.1.1l [24 Aug 2021]
*) Fixed an SM2 Decryption Buffer Overflow.
In order to decrypt SM2 encrypted data an application is expected
to call the API function EVP_PKEY_decrypt(). Typically an application
will call this function twice. The first time, on entry, the "out"
parameter can be NULL and, on exit, the "outlen" parameter is
populated with the buffer size required to hold the decrypted
plaintext. The application can then allocate a sufficiently sized
buffer and call EVP_PKEY_decrypt() again, but this time passing
a non-NULL value for the "out" parameter.
A bug in the implementation of the SM2 decryption code means that
the calculation of the buffer size required to hold the plaintext
returned by the first call to EVP_PKEY_decrypt() can be smaller
than the actual size required by the second call. This can lead to
a buffer overflow when EVP_PKEY_decrypt() is called by the application
a second time with a buffer that is too small.
A malicious attacker who is able present SM2 content for decryption
to an application could cause attacker chosen data to overflow the
buffer by up to a maximum of 62 bytes altering the contents of
other data held after the buffer, possibly changing application
behaviour or causing the application to crash. The location of the
buffer is application dependent but is typically heap allocated.
(CVE-2021-3711)
[Matt Caswell]
*) Fixed various read buffer overruns processing ASN.1 strings
ASN.1 strings are represented internally within OpenSSL as an
ASN1_STRING structure which contains a buffer holding the string
data and a field holding the buffer length. This contrasts with
normal C strings which are repesented as a buffer for the string
data which is terminated with a NUL (0) byte.
Although not a strict requirement, ASN.1 strings that are parsed
using OpenSSL's own "d2i" functions (and other similar parsing
functions) as well as any string whose value has been set with the
ASN1_STRING_set() function will additionally NUL terminate the byte
array in the ASN1_STRING structure.
However, it is possible for applications to directly construct
valid ASN1_STRING structures which do not NUL terminate the byte
array by directly setting the "data" and "length" fields in the
ASN1_STRING array. This can also happen by using the ASN1_STRING_set0()
function.
Numerous OpenSSL functions that print ASN.1 data have been found
to assume that the ASN1_STRING byte array will be NUL terminated,
even though this is not guaranteed for strings that have been
directly constructed. Where an application requests an ASN.1
structure to be printed, and where that ASN.1 structure contains
ASN1_STRINGs that have been directly constructed by the application
without NUL terminating the "data" field, then a read buffer overrun
can occur.
The same thing can also occur during name constraints processing
of certificates (for example if a certificate has been directly
constructed by the application instead of loading it via the OpenSSL
parsing functions, and the certificate contains non NUL terminated
ASN1_STRING structures). It can also occur in the X509_get1_email(),
X509_REQ_get1_email() and X509_get1_ocsp() functions.
If a malicious actor can cause an application to directly construct
an ASN1_STRING and then process it through one of the affected
OpenSSL functions then this issue could be hit. This might result
in a crash (causing a Denial of Service attack). It could also
result in the disclosure of private memory contents (such as private
keys, or sensitive plaintext).
(CVE-2021-3712)
[Matt Caswell]
OpenSSH 8.7 has deprecated ChallengeResponseAuthentication, but not removed
it. It is now an alias for KbdInteractiveAuthentication (as are the prior
aliases of ChallengeResponseAuthentication).
I think this chunk was accidentally dropped in the OpenSSH 8.7 merge.
Imminent deprecation notice
===========================
OpenSSH will disable the ssh-rsa signature scheme by default in the
next release.
In the SSH protocol, the "ssh-rsa" signature scheme uses the SHA-1
hash algorithm in conjunction with the RSA public key algorithm.
It is now possible[1] to perform chosen-prefix attacks against the
SHA-1 algorithm for less than USD$50K.
Note that the deactivation of "ssh-rsa" signatures does not necessarily
require cessation of use for RSA keys. In the SSH protocol, keys may be
capable of signing using multiple algorithms. In particular, "ssh-rsa"
keys are capable of signing using "rsa-sha2-256" (RSA/SHA256),
"rsa-sha2-512" (RSA/SHA512) and "ssh-rsa" (RSA/SHA1). Only the last of
these is being turned off by default.
This algorithm is unfortunately still used widely despite the
existence of better alternatives, being the only remaining public key
signature algorithm specified by the original SSH RFCs that is still
enabled by default.
The better alternatives include:
* The RFC8332 RSA SHA-2 signature algorithms rsa-sha2-256/512. These
algorithms have the advantage of using the same key type as
"ssh-rsa" but use the safe SHA-2 hash algorithms. These have been
supported since OpenSSH 7.2 and are already used by default if the
client and server support them.
* The RFC8709 ssh-ed25519 signature algorithm. It has been supported
in OpenSSH since release 6.5.
* The RFC5656 ECDSA algorithms: ecdsa-sha2-nistp256/384/521. These
have been supported by OpenSSH since release 5.7.
To check whether a server is using the weak ssh-rsa public key
algorithm, for host authentication, try to connect to it after
removing the ssh-rsa algorithm from ssh(1)'s allowed list:
ssh -oHostKeyAlgorithms=-ssh-rsa user@host
If the host key verification fails and no other supported host key
types are available, the server software on that host should be
upgraded.
OpenSSH recently enabled the UpdateHostKeys option by default to
assist the client by automatically migrating to better algorithms.
[1] "SHA-1 is a Shambles: First Chosen-Prefix Collision on SHA-1 and
Application to the PGP Web of Trust" Leurent, G and Peyrin, T
(2020) https://eprint.iacr.org/2020/014.pdf
Potentially-incompatible changes
================================
This release includes a number of changes that may affect existing
configurations:
* scp(1): this release changes the behaviour of remote to remote
copies (e.g. "scp host-a:/path host-b:") to transfer through the
local host by default. This was previously available via the -3
flag. This mode avoids the need to expose credentials on the
origin hop, avoids triplicate interpretation of filenames by the
shell (by the local system, the copy origin and the destination)
and, in conjunction with the SFTP support for scp(1) mentioned
below, allows use of all authentication methods to the remote
hosts (previously, only non-interactive methods could be used).
A -R flag has been added to select the old behaviour.
* ssh(1)/sshd(8): both the client and server are now using a
stricter configuration file parser. The new parser uses more
shell-like rules for quotes, space and escape characters. It is
also more strict in rejecting configurations that include options
lacking arguments. Previously some options (e.g. DenyUsers) could
appear on a line with no subsequent arguments. This release will
reject such configurations. The new parser will also reject
configurations with unterminated quotes and multiple '='
characters after the option name.
* ssh(1): when using SSHFP DNS records for host key verification,
ssh(1) will verify all matching records instead of just those
with the specific signature type requested. This may cause host
key verification problems if stale SSHFP records of a different
or legacy signature type exist alongside other records for a
particular host. bz#3322
* ssh-keygen(1): when generating a FIDO key and specifying an
explicit attestation challenge (using -Ochallenge), the challenge
will now be hashed by the builtin security key middleware. This
removes the (undocumented) requirement that challenges be exactly
32 bytes in length and matches the expectations of libfido2.
* sshd(8): environment="..." directives in authorized_keys files are
now first-match-wins and limited to 1024 discrete environment
variable names.
Changes since OpenSSH 8.6
=========================
This release contains a mix of new features and bug-fixes.
New features
------------
- scp(1): experimental support for transfers using the SFTP protocol
as a replacement for the venerable SCP/RCP protocol that it has
traditionally used. SFTP offers more predictable filename handling
and does not require expansion of glob(3) patterns via the shell
on the remote side.
SFTP support may be enabled via a temporary scp -s flag. It is
intended for SFTP to become the default transfer mode in the
near future, at which time the -s flag will be removed. The -O
flag exists to force use of the original SCP/RCP protocol for
cases where SFTP may be unavailable or incompatible.
- sftp-server(8): add a protocol extension to support expansion of
~/ and ~user/ prefixed paths. This was added to support these
paths when used by scp(1) while in SFTP mode.
- ssh(1): add a ForkAfterAuthentication ssh_config(5) counterpart to
the ssh(1) -f flag. GHPR#231
- ssh(1): add a StdinNull directive to ssh_config(5) that allows the
config file to do the same thing as -n does on the ssh(1) command-
line. GHPR#231
- ssh(1): add a SessionType directive to ssh_config, allowing the
configuration file to offer equivalent control to the -N (no
session) and -s (subsystem) command-line flags. GHPR#231
- ssh-keygen(1): allowed signers files used by ssh-keygen(1)
signatures now support listing key validity intervals alongside
they key, and ssh-keygen(1) can optionally check during signature
verification whether a specified time falls inside this interval.
This feature is intended for use by git to support signing and
verifying objects using ssh keys.
- ssh-keygen(8): support printing of the full public key in a sshsig
signature via a -Oprint-pubkey flag.
Bugfixes
--------
* ssh(1)/sshd(8): start time-based re-keying exactly on schedule in
the client and server mainloops. Previously the re-key timeout
could expire but re-keying would not start until a packet was sent
or received, causing a spin in select() if the connection was
quiescent.
* ssh-keygen(1): avoid Y2038 problem in printing certificate
validity lifetimes. Dates past 2^31-1 seconds since epoch were
displayed incorrectly on some platforms. bz#3329
* scp(1): allow spaces to appear in usernames for local to remote
and scp -3 remote to remote copies. bz#1164
* ssh(1)/sshd(8): remove references to ChallengeResponseAuthentication
in favour of KbdInteractiveAuthentication. The former is what was in
SSHv1, the latter is what is in SSHv2 (RFC4256) and they were
treated as somewhat but not entirely equivalent. We retain the old
name as a deprecated alias so configuration files continue to work
as well as a reference in the man page for people looking for it.
bz#3303
* ssh(1)/ssh-add(1)/ssh-keygen(1): fix decoding of X.509 subject name
when extracting a key from a PKCS#11 certificate. bz#3327
* ssh(1): restore blocking status on stdio fds before close. ssh(1)
needs file descriptors in non-blocking mode to operate but it was
not restoring the original state on exit. This could cause
problems with fds shared with other programs via the shell,
bz#3280 and GHPR#246
* ssh(1)/sshd(8): switch both client and server mainloops from
select(3) to pselect(3). Avoids race conditions where a signal
may arrive immediately before select(3) and not be processed until
an event fires. bz#2158
* ssh(1): sessions started with ControlPersist were incorrectly
executing a shell when the -N (no shell) option was specified.
bz#3290
* ssh(1): check if IPQoS or TunnelDevice are already set before
overriding. Prevents values in config files from overriding values
supplied on the command line. bz#3319
* ssh(1): fix debug message when finding a private key to match a
certificate being attempted for user authentication. Previously it
would print the certificate's path, whereas it was supposed to be
showing the private key's path. GHPR#247
* sshd(8): match host certificates against host public keys, not
private keys. Allows use of certificates with private keys held in
a ssh-agent. bz#3524
* ssh(1): add a workaround for a bug in OpenSSH 7.4 sshd(8), which
allows RSA/SHA2 signatures for public key authentication but fails
to advertise this correctly via SSH2_MSG_EXT_INFO. This causes
clients of these server to incorrectly match
PubkeyAcceptedAlgorithmse and potentially refuse to offer valid
keys. bz#3213
* sftp(1)/scp(1): degrade gracefully if a sftp-server offers the
limits@openssh.com extension but fails when the client tries to
invoke it. bz#3318
* ssh(1): allow ssh_config SetEnv to override $TERM, which is
otherwise handled specially by the protocol. Useful in ~/.ssh/config
to set TERM to something generic (e.g. "xterm" instead of
"xterm-256color") for destinations that lack terminfo entries.
* sftp-server(8): the limits@openssh.com extension was incorrectly
marked as an operation that writes to the filesystem, which made it
unavailable in sftp-server read-only mode. bz#3318
* ssh(1): fix SEGV in UpdateHostkeys debug() message, triggered when
the update removed more host keys than remain present.
* many manual page fixes.
Portability
-----------
* ssh(1): move closefrom() to before first malloc. When built against
tcmalloc, the closefrom() would stomp on file descriptors created
for tcmalloc's internal use. bz#3321
* sshd(8): handle GIDs > 2^31 in getgrouplist. When compiled in 32bit
mode, the getgrouplist implementation may fail for GIDs greater than
LONG_MAX.
* ssh(1): xstrdup environment variable used by ForwardAgent. bz#3328
* sshd(8): don't sigdie() in signal handler in privsep child process;
this can end up causing sandbox violations per bz3286
The conversion from 'unsigned long' to 'int' in line 805 is due to the
laziness of declaring a carry flag as BN_ULONG, to save an extra
line of declaration.
The constants in conditional context come from the macro 'bn_cp_32'.
The unconst cast is used for initializing local BIGNUM constants; the
struct member is declared as non-const pointer.
The type widths are handled carefully, so even if there is some
conversion from 64-bit long to uint32_t, no value bits get lost.
The fallthrough case statements are a variant of Duff's Device.
The bitwise '>>' on signed value is actually on a value of type
'unsigned char', and since all platforms supported by lint have
sizeof(int) == 4, the behavior is well defined.
Fixed a problem with verifying a certificate chain when using the
X509_V_FLAG_X509_STRICT flag. This flag enables additional security
checks of the certificates present in a certificate chain. It is
not set by default.
Starting from OpenSSL version 1.1.1h a check to disallow certificates
in the chain that have explicitly encoded elliptic curve parameters
was added as an additional strict check.
An error in the implementation of this check meant that the result
of a previous check to confirm that certificates in the chain are
valid CA certificates was overwritten. This effectively bypasses
the check that non-CA certificates must not be able to issue other
certificates.
If a "purpose" has been configured then there is a subsequent
opportunity for checks that the certificate is a valid CA. All of
the named "purpose" values implemented in libcrypto perform this
check. Therefore, where a purpose is set the certificate chain will
still be rejected even when the strict flag has been used. A purpose
is set by default in libssl client and server certificate verification
routines, but it can be overridden or removed by an application.
In order to be affected, an application must explicitly set the
X509_V_FLAG_X509_STRICT verification flag and either not set a
purpose for the certificate verification or, in the case of TLS
client or server applications, override the default purpose.
([CVE-2021-3450])
Tomasz Mraz
Fixed an issue where an OpenSSL TLS server may crash if sent a
maliciously crafted renegotiation ClientHello message from a client.
If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms
extension (where it was present in the initial ClientHello), but
includes a signature_algorithms_cert extension then a NULL pointer
dereference will result, leading to a crash and a denial of service
attack.
A server is only vulnerable if it has TLSv1.2 and renegotiation
enabled (which is the default configuration). OpenSSL TLS clients
are not impacted by this issue. ([CVE-2021-3449])
Peter Kaestle and Samuel Sapalski
OpenSSH 8.5 was released on 2021-03-03. 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
Future deprecation notice
=========================
It is now possible[1] to perform chosen-prefix attacks against the
SHA-1 algorithm for less than USD$50K.
In the SSH protocol, the "ssh-rsa" signature scheme uses the SHA-1
hash algorithm in conjunction with the RSA public key algorithm.
OpenSSH will disable this signature scheme by default in the near
future.
Note that the deactivation of "ssh-rsa" signatures does not necessarily
require cessation of use for RSA keys. In the SSH protocol, keys may be
capable of signing using multiple algorithms. In particular, "ssh-rsa"
keys are capable of signing using "rsa-sha2-256" (RSA/SHA256),
"rsa-sha2-512" (RSA/SHA512) and "ssh-rsa" (RSA/SHA1). Only the last of
these is being turned off by default.
This algorithm is unfortunately still used widely despite the
existence of better alternatives, being the only remaining public key
signature algorithm specified by the original SSH RFCs that is still
enabled by default.
The better alternatives include:
* The RFC8332 RSA SHA-2 signature algorithms rsa-sha2-256/512. These
algorithms have the advantage of using the same key type as
"ssh-rsa" but use the safe SHA-2 hash algorithms. These have been
supported since OpenSSH 7.2 and are already used by default if the
client and server support them.
* The RFC8709 ssh-ed25519 signature algorithm. It has been supported
in OpenSSH since release 6.5.
* The RFC5656 ECDSA algorithms: ecdsa-sha2-nistp256/384/521. These
have been supported by OpenSSH since release 5.7.
To check whether a server is using the weak ssh-rsa public key
algorithm, for host authentication, try to connect to it after
removing the ssh-rsa algorithm from ssh(1)'s allowed list:
ssh -oHostKeyAlgorithms=-ssh-rsa user@host
If the host key verification fails and no other supported host key
types are available, the server software on that host should be
upgraded.
This release enables the UpdateHostKeys option by default to assist
the client by automatically migrating to better algorithms.
[1] "SHA-1 is a Shambles: First Chosen-Prefix Collision on SHA-1 and
Application to the PGP Web of Trust" Leurent, G and Peyrin, T
(2020) https://eprint.iacr.org/2020/014.pdf
Security
========
* ssh-agent(1): fixed a double-free memory corruption that was
introduced in OpenSSH 8.2 . We treat all such memory faults as
potentially exploitable. This bug could be reached by an attacker
with access to the agent socket.
On modern operating systems where the OS can provide information
about the user identity connected to a socket, OpenSSH ssh-agent
and sshd limit agent socket access only to the originating user
and root. Additional mitigation may be afforded by the system's
malloc(3)/free(3) implementation, if it detects double-free
conditions.
The most likely scenario for exploitation is a user forwarding an
agent either to an account shared with a malicious user or to a
host with an attacker holding root access.
* Portable sshd(8): Prevent excessively long username going to PAM.
This is a mitigation for a buffer overflow in Solaris' PAM username
handling (CVE-2020-14871), and is only enabled for Sun-derived PAM
implementations. This is not a problem in sshd itself, it only
prevents sshd from being used as a vector to attack Solaris' PAM.
It does not prevent the bug in PAM from being exploited via some
other PAM application. GHPR212
Potentially-incompatible changes
================================
This release includes a number of changes that may affect existing
configurations:
* ssh(1), sshd(8): this release changes the first-preference signature
algorithm from ECDSA to ED25519.
* ssh(1), sshd(8): set the TOS/DSCP specified in the configuration
for interactive use prior to TCP connect. The connection phase of
the SSH session is time-sensitive and often explicitly interactive.
The ultimate interactive/bulk TOS/DSCP will be set after
authentication completes.
* ssh(1), sshd(8): remove the pre-standardization cipher
rijndael-cbc@lysator.liu.se. It is an alias for aes256-cbc before
it was standardized in RFC4253 (2006), has been deprecated and
disabled by default since OpenSSH 7.2 (2016) and was only briefly
documented in ssh.1 in 2001.
* ssh(1), sshd(8): update/replace the experimental post-quantum
hybrid key exchange method based on Streamlined NTRU Prime coupled
with X25519.
The previous sntrup4591761x25519-sha512@tinyssh.org method is
replaced with sntrup761x25519-sha512@openssh.com. Per its
designers, the sntrup4591761 algorithm was superseded almost two
years ago by sntrup761.
(note this both the updated method and the one that it replaced are
disabled by default)
* ssh(1): disable CheckHostIP by default. It provides insignificant
benefits while making key rotation significantly more difficult,
especially for hosts behind IP-based load-balancers.
Changes since OpenSSH 8.4
=========================
New features
------------
* ssh(1): this release enables UpdateHostkeys by default subject to
some conservative preconditions:
- The key was matched in the UserKnownHostsFile (and not in the
GlobalKnownHostsFile).
- The same key does not exist under another name.
- A certificate host key is not in use.
- known_hosts contains no matching wildcard hostname pattern.
- VerifyHostKeyDNS is not enabled.
- The default UserKnownHostsFile is in use.
We expect some of these conditions will be modified or relaxed in
future.
* ssh(1), sshd(8): add a new LogVerbose configuration directive for
that allows forcing maximum debug logging by file/function/line
pattern-lists.
* ssh(1): when prompting the user to accept a new hostkey, display
any other host names/addresses already associated with the key.
* ssh(1): allow UserKnownHostsFile=none to indicate that no
known_hosts file should be used to identify host keys.
* ssh(1): add a ssh_config KnownHostsCommand option that allows the
client to obtain known_hosts data from a command in addition to
the usual files.
* ssh(1): add a ssh_config PermitRemoteOpen option that allows the
client to restrict the destination when RemoteForward is used
with SOCKS.
* ssh(1): for FIDO keys, if a signature operation fails with a
"incorrect PIN" reason and no PIN was initially requested from the
user, then request a PIN and retry the operation. This supports
some biometric devices that fall back to requiring PIN when reading
of the biometric failed, and devices that require PINs for all
hosted credentials.
* sshd(8): implement client address-based rate-limiting via new
sshd_config(5) PerSourceMaxStartups and PerSourceNetBlockSize
directives that provide more fine-grained control on a per-origin
address basis than the global MaxStartups limit.
Bugfixes
--------
* ssh(1): Prefix keyboard interactive prompts with "(user@host)" to
make it easier to determine which connection they are associated
with in cases like scp -3, ProxyJump, etc. bz#3224
* sshd(8): fix sshd_config SetEnv directives located inside Match
blocks. GHPR201
* ssh(1): when requesting a FIDO token touch on stderr, inform the
user once the touch has been recorded.
* ssh(1): prevent integer overflow when ridiculously large
ConnectTimeout values are specified, capping the effective value
(for most platforms) at 24 days. bz#3229
* ssh(1): consider the ECDSA key subtype when ordering host key
algorithms in the client.
* ssh(1), sshd(8): rename the PubkeyAcceptedKeyTypes keyword to
PubkeyAcceptedAlgorithms. The previous name incorrectly suggested
that it control allowed key algorithms, when this option actually
specifies the signature algorithms that are accepted. The previous
name remains available as an alias. bz#3253
* ssh(1), sshd(8): similarly, rename HostbasedKeyTypes (ssh) and
HostbasedAcceptedKeyTypes (sshd) to HostbasedAcceptedAlgorithms.
* sftp-server(8): add missing lsetstat@openssh.com documentation
and advertisement in the server's SSH2_FXP_VERSION hello packet.
* ssh(1), sshd(8): more strictly enforce KEX state-machine by
banning packet types once they are received. Fixes memleak caused
by duplicate SSH2_MSG_KEX_DH_GEX_REQUEST (oss-fuzz #30078).
* sftp(1): allow the full range of UIDs/GIDs for chown/chgrp on 32bit
platforms instead of being limited by LONG_MAX. bz#3206
* Minor man page fixes (capitalization, commas, etc.) bz#3223
* sftp(1): when doing an sftp recursive upload or download of a
read-only directory, ensure that the directory is created with
write and execute permissions in the interim so that the transfer
can actually complete, then set the directory permission as the
final step. bz#3222
* ssh-keygen(1): document the -Z, check the validity of its argument
earlier and provide a better error message if it's not correct.
bz#2879
* ssh(1): ignore comments at the end of config lines in ssh_config,
similar to what we already do for sshd_config. bz#2320
* sshd_config(5): mention that DisableForwarding is valid in a
sshd_config Match block. bz3239
* sftp(1): fix incorrect sorting of "ls -ltr" under some
circumstances. bz3248.
* ssh(1), sshd(8): fix potential integer truncation of (unlikely)
timeout values. bz#3250
* ssh(1): make hostbased authentication send the signature algorithm
in its SSH2_MSG_USERAUTH_REQUEST packets instead of the key type.
This make HostbasedAcceptedAlgorithms do what it is supposed to -
filter on signature algorithm and not key type.
Portability
-----------
* sshd(8): add a number of platform-specific syscalls to the Linux
seccomp-bpf sandbox. bz#3232 bz#3260
* sshd(8): remove debug message from sigchld handler that could cause
deadlock on some platforms. bz#3259
* Sync contrib/ssh-copy-id with upstream.
* unittests: add a hostname function for systems that don't have it.
Some systems don't have a hostname command (it's not required by
POSIX). The do have uname -n (which is), but not all of those have
it report the FQDN.
Checksums:
==========
- SHA1 (openssh-8.5.tar.gz) = 04cae43c389fb411227c01219e4eb46e3113f34e
- SHA256 (openssh-8.5.tar.gz) = 5qB2CgzNG4io4DmChTjHgCWqRWvEOvCKJskLdJCz+SU=
- SHA1 (openssh-8.5p1.tar.gz) = 72eadcbe313b07b1dd3b693e41d3cd56d354e24e
- SHA256 (openssh-8.5p1.tar.gz) = 9S8/QdQpqpkY44zyAK8iXM3Y5m8FLaVyhwyJc3ZG7CU=
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
Please note that the OpenPGP key used to sign releases has been
rotated for this release. The new key has been signed by the previous
key to provide continuity.
Reporting Bugs:
===============
- Please read https://www.openssh.com/report.html
Security bugs should be reported directly to openssh@openssh.com
*) Fixed the X509_issuer_and_serial_hash() function. It attempts
to create a unique hash value based on the issuer and serial
number data contained within an X509 certificate. However it
was failing to correctly handle any errors that may occur
while parsing the issuer field (which might occur if the issuer
field is maliciously constructed). This may subsequently result
in a NULL pointer deref and a crash leading to a potential
denial of service attack.
(CVE-2021-23841)
[Matt Caswell]
*) Fixed the RSA_padding_check_SSLv23() function and the
RSA_SSLV23_PADDING padding mode to correctly check for rollback
attacks. This is considered a bug in OpenSSL 1.1.1 because it
does not support SSLv2. In 1.0.2 this is CVE-2021-23839.
[Matt Caswell]
*) Fixed the EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate
functions. Previously they could overflow the output length
argument in some cases where the input length is close to the
maximum permissable length for an integer on the platform. In
such cases the return value from the function call would be
1 (indicating success), but the output length value would be
negative. This could cause applications to behave incorrectly
or crash.
(CVE-2021-23840)
[Matt Caswell]
*) Fixed SRP_Calc_client_key so that it runs in constant time.
The previous implementation called BN_mod_exp without setting
BN_FLG_CONSTTIME. This could be exploited in a side channel
attack to recover the password. Since the attack is local host
only this is outside of the current OpenSSL threat model and
therefore no CVE is assigned.
Thanks to Mohammed Sabt and Daniel De Almeida Braga for reporting
this issue.
[Matt Caswell]
Fixed NULL pointer deref in the GENERAL_NAME_cmp function This
function could crash if both GENERAL_NAMEs contain an EDIPARTYNAME.
If an attacker can control both items being compared then this
could lead to a possible denial of service attack. OpenSSL itself
uses the GENERAL_NAME_cmp function for two purposes:
Comparing CRL distribution point names between an available CRL
and a CRL distribution point embedded in an X509 certificate When
verifying that a timestamp response token signer matches the
timestamp authority name (exposed via the API functions
TS_RESP_verify_response and TS_RESP_verify_token) (CVE-2020-1971)
Matt Caswell
Changes between 1.1.1g and 1.1.1h [22 Sep 2020]
Certificates with explicit curve parameters are now disallowed in
verification chains if the X509_V_FLAG_X509_STRICT flag is used.
Tomas Mraz
The 'MinProtocol' and 'MaxProtocol' configuration commands now
silently ignore TLS protocol version bounds when configuring
DTLS-based contexts, and conversely, silently ignore DTLS protocol
version bounds when configuring TLS-based contexts. The commands
can be repeated to set bounds of both types. The same applies with
the corresponding "min_protocol" and "max_protocol" command-line
switches, in case some application uses both TLS and DTLS.
SSL_CTX instances that are created for a fixed protocol version
(e.g. TLSv1_server_method()) also silently ignore version bounds.
Previously attempts to apply bounds to these protocol versions
would result in an error. Now only the "version-flexible" SSL_CTX
instances are subject to limits in configuration files in command-line
options.
Viktor Dukhovni
Handshake now fails if Extended Master Secret extension is dropped
on renegotiation.
Tomas Mraz
The Oracle Developer Studio compiler will start reporting deprecated
APIs
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
Future deprecation notice
=========================
It is now possible[1] to perform chosen-prefix attacks against the
SHA-1 algorithm for less than USD$50K. For this reason, we will be
disabling the "ssh-rsa" public key signature algorithm by default in a
near-future release.
This algorithm is unfortunately still used widely despite the
existence of better alternatives, being the only remaining public key
signature algorithm specified by the original SSH RFCs.
The better alternatives include:
* The RFC8332 RSA SHA-2 signature algorithms rsa-sha2-256/512. These
algorithms have the advantage of using the same key type as
"ssh-rsa" but use the safe SHA-2 hash algorithms. These have been
supported since OpenSSH 7.2 and are already used by default if the
client and server support them.
* The ssh-ed25519 signature algorithm. It has been supported in
OpenSSH since release 6.5.
* The RFC5656 ECDSA algorithms: ecdsa-sha2-nistp256/384/521. These
have been supported by OpenSSH since release 5.7.
To check whether a server is using the weak ssh-rsa public key
algorithm, for host authentication, try to connect to it after
removing the ssh-rsa algorithm from ssh(1)'s allowed list:
ssh -oHostKeyAlgorithms=-ssh-rsa user@host
If the host key verification fails and no other supported host key
types are available, the server software on that host should be
upgraded.
We intend to enable UpdateHostKeys by default in the next OpenSSH
release. This will assist the client by automatically migrating to
better algorithms. Users may consider enabling this option manually.
[1] "SHA-1 is a Shambles: First Chosen-Prefix Collision on SHA-1 and
Application to the PGP Web of Trust" Leurent, G and Peyrin, T
(2020) https://eprint.iacr.org/2020/014.pdf
Security
========
* ssh-agent(1): restrict ssh-agent from signing web challenges for
FIDO/U2F keys.
When signing messages in ssh-agent using a FIDO key that has an
application string that does not start with "ssh:", ensure that the
message being signed is one of the forms expected for the SSH protocol
(currently public key authentication and sshsig signatures).
This prevents ssh-agent forwarding on a host that has FIDO keys
attached granting the ability for the remote side to sign challenges
for web authentication using those keys too.
Note that the converse case of web browsers signing SSH challenges is
already precluded because no web RP can have the "ssh:" prefix in the
application string that we require.
* ssh-keygen(1): Enable FIDO 2.1 credProtect extension when generating
a FIDO resident key.
The recent FIDO 2.1 Client to Authenticator Protocol introduced a
"credProtect" feature to better protect resident keys. We use this
option to require a PIN prior to all operations that may retrieve
a resident key from a FIDO token.
Potentially-incompatible changes
================================
This release includes a number of changes that may affect existing
configurations:
* For FIDO/U2F support, OpenSSH recommends the use of libfido2 1.5.0
or greater. Older libraries have limited support at the expense of
disabling particular features. These include resident keys, PIN-
required keys and multiple attached tokens.
* ssh-keygen(1): the format of the attestation information optionally
recorded when a FIDO key is generated has changed. It now includes
the authenticator data needed to validate attestation signatures.
* The API between OpenSSH and the FIDO token middleware has changed
and the SSH_SK_VERSION_MAJOR version has been incremented as a
result. Third-party middleware libraries must support the current
API version (7) to work with OpenSSH 8.4.
* The portable OpenSSH distribution now requires automake to rebuild
the configure script and supporting files. This is not required when
simply building portable OpenSSH from a release tar file.
Changes since OpenSSH 8.3
=========================
New features
------------
* ssh(1), ssh-keygen(1): support for FIDO keys that require a PIN for
each use. These keys may be generated using ssh-keygen using a new
"verify-required" option. When a PIN-required key is used, the user
will be prompted for a PIN to complete the signature operation.
* sshd(8): authorized_keys now supports a new "verify-required"
option to require FIDO signatures assert that the token verified
that the user was present before making the signature. The FIDO
protocol supports multiple methods for user-verification, but
currently OpenSSH only supports PIN verification.
* sshd(8), ssh-keygen(1): add support for verifying FIDO webauthn
signatures. Webauthn is a standard for using FIDO keys in web
browsers. These signatures are a slightly different format to plain
FIDO signatures and thus require explicit support.
* ssh(1): allow some keywords to expand shell-style ${ENV}
environment variables. The supported keywords are CertificateFile,
ControlPath, IdentityAgent and IdentityFile, plus LocalForward and
RemoteForward when used for Unix domain socket paths. bz#3140
* ssh(1), ssh-agent(1): allow some additional control over the use of
ssh-askpass via a new $SSH_ASKPASS_REQUIRE environment variable,
including forcibly enabling and disabling its use. bz#69
* ssh(1): allow ssh_config(5)'s AddKeysToAgent keyword accept a time
limit for keys in addition to its current flag options. Time-
limited keys will automatically be removed from ssh-agent after
their expiry time has passed.
* scp(1), sftp(1): allow the -A flag to explicitly enable agent
forwarding in scp and sftp. The default remains to not forward an
agent, even when ssh_config enables it.
* ssh(1): add a '%k' TOKEN that expands to the effective HostKey of
the destination. This allows, e.g., keeping host keys in individual
files using "UserKnownHostsFile ~/.ssh/known_hosts.d/%k". bz#1654
* ssh(1): add %-TOKEN, environment variable and tilde expansion to
the UserKnownHostsFile directive, allowing the path to be
completed by the configuration (e.g. bz#1654)
* ssh-keygen(1): allow "ssh-add -d -" to read keys to be deleted
from stdin. bz#3180
* sshd(8): improve logging for MaxStartups connection throttling.
sshd will now log when it starts and stops throttling and periodically
while in this state. bz#3055
Bugfixes
--------
* ssh(1), ssh-keygen(1): better support for multiple attached FIDO
tokens. In cases where OpenSSH cannot unambiguously determine which
token to direct a request to, the user is now required to select a
token by touching it. In cases of operations that require a PIN to
be verified, this avoids sending the wrong PIN to the wrong token
and incrementing the token's PIN failure counter (tokens
effectively erase their keys after too many PIN failures).
* sshd(8): fix Include before Match in sshd_config; bz#3122
* ssh(1): close stdin/out/error when forking after authentication
completes ("ssh -f ...") bz#3137
* ssh(1), sshd(8): limit the amount of channel input data buffered,
avoiding peers that advertise large windows but are slow to read
from causing high memory consumption.
* ssh-agent(1): handle multiple requests sent in a single write() to
the agent.
* sshd(8): allow sshd_config longer than 256k
* sshd(8): avoid spurious "Unable to load host key" message when sshd
load a private key but no public counterpart
* ssh(1): prefer the default hostkey algorithm list whenever we have
a hostkey that matches its best-preference algorithm.
* sshd(1): when ordering the hostkey algorithms to request from a
server, prefer certificate types if the known_hosts files contain a key
marked as a @cert-authority; bz#3157
* ssh(1): perform host key fingerprint comparisons for the "Are you
sure you want to continue connecting (yes/no/[fingerprint])?"
prompt with case sensitivity.
* sshd(8): ensure that address/masklen mismatches in sshd_config
yield fatal errors at daemon start time rather than later when
they are evaluated.
* ssh-keygen(1): ensure that certificate extensions are lexically
sorted. Previously if the user specified a custom extension then
the everything would be in order except the custom ones. bz#3198
* ssh(1): also compare username when checking for JumpHost loops.
bz#3057
* ssh-keygen(1): preserve group/world read permission on known_hosts
files across runs of "ssh-keygen -Rf /path". The old behaviour was
to remove all rights for group/other. bz#3146
* ssh-keygen(1): Mention the [-a rounds] flag in the ssh-keygen
manual page and usage().
* sshd(8): explicitly construct path to ~/.ssh/rc rather than
relying on it being relative to the current directory, so that it
can still be found if the shell startup changes its directory.
bz#3185
* sshd(8): when redirecting sshd's log output to a file, undo this
redirection after the session child process is forked(). Fixes
missing log messages when using this feature under some
circumstances.
* sshd(8): start ClientAliveInterval bookkeeping before first pass
through select() loop; fixed theoretical case where busy sshd may
ignore timeouts from client.
* ssh(1): only reset the ServerAliveInterval check when we receive
traffic from the server and ignore traffic from a port forwarding
client, preventing a client from keeping a connection alive when
it should be terminated. bz#2265
* ssh-keygen(1): avoid spurious error message when ssh-keygen
creates files outside ~/.ssh
* sftp-client(1): fix off-by-one error that caused sftp downloads to
make one more concurrent request that desired. This prevented using
sftp(1) in unpipelined request/response mode, which is useful when
debugging. bz#3054
* ssh(1), sshd(8): handle EINTR in waitfd() and timeout_connect()
helpers. bz#3071
* ssh(1), ssh-keygen(1): defer creation of ~/.ssh until we attempt to
write to it so we don't leave an empty .ssh directory when it's not
needed. bz#3156
* ssh(1), sshd(8): fix multiplier when parsing time specifications
when handling seconds after other units. bz#3171
Portability
-----------
* sshd(8): always send any PAM account messages. If the PAM account
stack returns any messages, always send them to the user and not
just if the check succeeds. bz#2049
* Implement some backwards compatibility for libfido2 libraries
older than 1.5.0. Note that use of an older library will result
in the loss of certain features including resident key support,
PIN support and support for multiple attached tokens.
* configure fixes for XCode 12
* gnome-ssh-askpass3: ensure the "close" button is not focused by
default for SSH_ASKPASS_PROMPT=none prompts. Avoids space/enter
accidentally dismissing FIDO touch notifications.
* gnome-ssh-askpass3: allow some control over textarea colour via
$GNOME_SSH_ASKPASS_FG_COLOR and $GNOME_SSH_ASKPASS_BG_COLOR
environment variables.
* sshd(8): document another PAM spec problem in a frustrated comment
* sshd(8): support NetBSD's utmpx.ut_ss address field. bz#960
* Add the ssh-sk-helper binary and its manpage to the RPM spec file
* Detect the Frankenstein monster of Linux/X32 and allow the sandbox
to function there. bz#3085
Cherry-picked from upstream:
https://git.savannah.gnu.org/gitweb/?p=config.git;a=commit;h=1c4398015583eb77bc043234f5734be055e64bea
Everything except external/apache2/llvm/dist/llvm/cmake/config.guess
is patched, which is under vendor tag and cannot be modified. I expect
that this file is not actually used as we use hand-crafted version of
configure script instead of cmake for building LLVM.
Note that external/apache2/llvm/autoconf/autoconf/config.guess has
already been committed on Oct. 20, but commit message disappeared as
cvs aborted due to "permission denied" when trying to modify the file
mentioned above. Sorry for confusing you.
Also note that GMP uses its own config.guess Patch for
external/lgpl3/gmp/dist/config.guess is provided by ryo@. Thanks!
christos