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merge conflicts between OpenSSH-9.8 and 9.9
Import OpenSSH-9.9 (previous was 9.8) Changes: Future deprecation notice ========================= OpenSSH plans to remove support for the DSA signature algorithm in early 2025. This release disables DSA by default at compile time. DSA, as specified in the SSHv2 protocol, is inherently weak - being limited to a 160 bit private key and use of the SHA1 digest. Its estimated security level is only 80 bits symmetric equivalent. OpenSSH has disabled DSA keys by default since 2015 but has retained run-time optional support for them. DSA was the only mandatory-to- implement algorithm in the SSHv2 RFCs, mostly because alternative algorithms were encumbered by patents when the SSHv2 protocol was specified. This has not been the case for decades at this point and better algorithms are well supported by all actively-maintained SSH implementations. We do not consider the costs of maintaining DSA in OpenSSH to be justified and hope that removing it from OpenSSH can accelerate its wider deprecation in supporting cryptography libraries. Currently DSA is disabled at compile time. The final step of removing DSA support entirely is planned for the first OpenSSH release of 2025. DSA support may be re-enabled on OpenBSD by setting "DSAKEY=yes" in Makefile.inc. To enable DSA support in portable OpenSSH, pass the "--enable-dsa-keys" option to configure. Potentially-incompatible changes -------------------------------- * ssh(1): remove support for pre-authentication compression. OpenSSH has only supported post-authentication compression in the server for some years. Compression before authentication significantly increases the attack surface of SSH servers and risks creating oracles that reveal information about information sent during authentication. * ssh(1), sshd(8): processing of the arguments to the "Match" configuration directive now follows more shell-like rules for quoted strings, including allowing nested quotes and \-escaped characters. If configurations contained workarounds for the previous simplistic quote handling then they may need to be adjusted. If this is the case, it's most likely to be in the arguments to a "Match exec" confition. In this case, moving the command to be evaluated from the Match line to an external shell script is easiest way to preserve compatibility with both the old and new versions. Changes since OpenSSH 9.8 ========================= This release contains a number of new features and bugfixes. New features ------------ * ssh(1), sshd(8): add support for a new hybrid post-quantum key exchange based on the FIPS 203 Module-Lattice Key Enapsulation mechanism (ML-KEM) combined with X25519 ECDH as described by https://datatracker.ietf.org/doc/html/draft-kampanakis-curdle-ssh-pq-ke-03 This algorithm "mlkem768x25519-sha256" is available by default. * ssh(1): the ssh_config "Include" directive can now expand environment as well as the same set of %-tokens "Match Exec" supports. * sshd(8): add a sshd_config "RefuseConnection" option that, if set will terminate the connection at the first authentication request. * sshd(8): add a "refuseconnection" penalty class to sshd_config PerSourcePenalties that is applied when a connection is dropped by the new RefuseConnection keyword. * sshd(8): add a "Match invalid-user" predicate to sshd_config Match options that matches when the target username is not valid on the server. * ssh(1), sshd(8): update the Streamlined NTRUPrime code to a substantially faster implementation. * ssh(1), sshd(8): the hybrid Streamlined NTRUPrime/X25519 key exchange algorithm now has an IANA-assigned name in addition to the "@openssh.com" vendor extension name. This algorithm is now also available under this name "sntrup761x25519-sha512" * ssh(1), sshd(8), ssh-agent(1): prevent private keys from being included in core dump files for most of their lifespans. This is in addition to pre-existing controls in ssh-agent(1) and sshd(8) that prevented coredumps. This feature is supported on OpenBSD, Linux and FreeBSD. * All: convert key handling to use the libcrypto EVP_PKEY API, with the exception of DSA. * sshd(8): add a random amount of jitter (up to 4 seconds) to the grace login time to make its expiry unpredictable. Bugfixes -------- * sshd(8): relax absolute path requirement back to what it was prior to OpenSSH 9.8, which incorrectly required that sshd was started with an absolute path in inetd mode. bz3717 * sshd(8): fix regression introduced in openssh-9.8 that swapped the order of source and destination addresses in some sshd log messages. * sshd(8): do not apply authorized_keys options when signature verification fails. Prevents more restrictive key options being incorrectly applied to subsequent keys in authorized_keys. bz3733 * ssh-keygen(1): include pathname in some of ssh-keygen's passphrase prompts. Helps the user know what's going on when ssh-keygen is invoked via other tools. Requested in GHPR503 * ssh(1), ssh-add(1): make parsing user@host consistently look for the last '@' in the string rather than the first. This makes it possible to more consistently use usernames that contain '@' characters. * ssh(1), sshd(8): be more strict in parsing key type names. Only allow short names (e.g "rsa") in user-interface code and require full SSH protocol names (e.g. "ssh-rsa") everywhere else. bz3725 * regress: many performance and correctness improvements to the re-keying regression test. * ssh-keygen(1): clarify that ed25519 is the default key type generated and clarify that rsa-sha2-512 is the default signature scheme when RSA is in use. GHPR505 * sshd(8): fix minor memory leak in Subsystem option parsing; GHPR515 * All: additional hardening and consistency checks for the sshbuf code. * sshd(8): reduce default logingrace penalty to ensure that a single forgotton login that times out will be below the penalty threshold. * ssh(1): fix proxy multiplexing (-O proxy) bug. If a mux started with ControlPersist then later has a forwarding added using mux proxy connection and the forwarding was used, then when the mux proxy session terminated, the mux master process would issue a bad message that terminated the connection. Portability ----------- * sync contrib/ssh-copy-id to the latest upstream version. * regress: improve portablility for some awk(1) usage (e.g. Solaris) * In the contrib/redhat RPM spec file, without_openssl was previously incorrectly enabled unconditionally. * sshd(8) restore audit call before exit that regressed in openssh-9.8 Fixes an issue where the SSH_CONNECTION_ABANDON event was not recorded. * sshd(8): add support for class-imposed loging restrictions on FreeBSD. Allowing auth_hostok(3) and auth_timeok(3) to control logins. * Build fixes for Musl libc. * Fix detection of setres*id on GNU/Hurd
Pull up the following, requested by kim in ticket #1780: crypto/external/bsd/openssh/Makefile.inc up to 1.15 (+patch) crypto/external/bsd/openssh/bin/Makefile.inc up to 1.4 crypto/external/bsd/openssh/bin/scp/Makefile up to 1.6 crypto/external/bsd/openssh/bin/sftp/Makefile up to 1.11 crypto/external/bsd/openssh/bin/sftp-server/Makefile up to 1.4 crypto/external/bsd/openssh/bin/ssh/Makefile up to 1.20 crypto/external/bsd/openssh/bin/ssh-add/Makefile up to 1.3 crypto/external/bsd/openssh/bin/ssh-agent/Makefile up to 1.7 crypto/external/bsd/openssh/bin/ssh-keygen/Makefile up to 1.10 crypto/external/bsd/openssh/bin/ssh-keyscan/Makefile up to 1.6 crypto/external/bsd/openssh/bin/ssh-pkcs11-helper/Makefile up to 1.4 crypto/external/bsd/openssh/bin/sshd/Makefile up to 1.27 (+patch) crypto/external/bsd/openssh/dist/PROTOCOL.sshsig up to 1.1.1.2 crypto/external/bsd/openssh/dist/srclimit.c up to 1.3 crypto/external/bsd/openssh/dist/sftp-realpath.c up to 1.3 crypto/external/bsd/openssh/dist/sntrup761.c up to 1.3 crypto/external/bsd/openssh/dist/sntrup761.sh up to 1.1.1.2 crypto/external/bsd/openssh/dist/sshsig.c up to 1.12 crypto/external/bsd/openssh/dist/sshsig.h up to 1.1.1.5 crypto/external/bsd/openssh/dist/addr.c up to 1.6 crypto/external/bsd/openssh/dist/PROTOCOL.u2f up to 1.1.1.3 crypto/external/bsd/openssh/dist/sk-api.h up to 1.1.1.6 crypto/external/bsd/openssh/dist/sk-usbhid.c up to 1.9 crypto/external/bsd/openssh/dist/ssh-ecdsa-sk.c up to 1.4 crypto/external/bsd/openssh/dist/ssh-ed25519-sk.c up to 1.5 crypto/external/bsd/openssh/dist/ssh-sk-client.c up to 1.6 crypto/external/bsd/openssh/dist/ssh-sk-helper.8 up to 1.1.1.2 crypto/external/bsd/openssh/dist/ssh-sk-helper.c up to 1.7 crypto/external/bsd/openssh/dist/ssh-sk.c up to 1.8 crypto/external/bsd/openssh/dist/ssh-sk.h up to 1.1.1.2 crypto/external/bsd/openssh/dist/sshbuf-io.c up to 1.2 crypto/external/bsd/openssh/dist/addr.h up to 1.1.1.2 crypto/external/bsd/openssh/dist/kexsntrup761x25519.c up to 1.3 crypto/external/bsd/openssh/dist/cipher-chachapoly-libcrypto.c up to 1.3 crypto/external/bsd/openssh/dist/srclimit.h up to 1.1.1.1 crypto/external/bsd/openssh/dist/auth2-pubkeyfile.c up to 1.3 crypto/external/bsd/openssh/dist/sftp-usergroup.c up to 1.3 crypto/external/bsd/openssh/dist/sftp-usergroup.h up to 1.1.1.1 crypto/external/bsd/openssh/dist/ed25519.sh up to 1.1.1.1 crypto/external/bsd/openssh/dist/crc32.c delete crypto/external/bsd/openssh/dist/crc32.h delete crypto/external/bsd/openssh/dist/fe25519.c delete crypto/external/bsd/openssh/dist/fe25519.h delete crypto/external/bsd/openssh/dist/ge25519.c delete crypto/external/bsd/openssh/dist/ge25519.h delete crypto/external/bsd/openssh/dist/ge25519_base.data delete crypto/external/bsd/openssh/dist/kexsntrup4591761x25519.c delete crypto/external/bsd/openssh/dist/sc25519.c delete crypto/external/bsd/openssh/dist/sc25519.h delete crypto/external/bsd/openssh/dist/sntrup4591761.c delete crypto/external/bsd/openssh/dist/sntrup4591761.sh delete crypto/external/bsd/openssh/dist/uuencode.c delete crypto/external/bsd/openssh/dist/uuencode.h delete crypto/external/bsd/openssh/dist/verify.c delete crypto/external/bsd/openssh/dist/LICENCE up to 1.7 crypto/external/bsd/openssh/dist/PROTOCOL up to 1.23 crypto/external/bsd/openssh/dist/PROTOCOL.agent up to 1.15 crypto/external/bsd/openssh/dist/PROTOCOL.certkeys up to 1.13 crypto/external/bsd/openssh/dist/PROTOCOL.chacha20poly1305 up to 1.1.1.4 crypto/external/bsd/openssh/dist/PROTOCOL.key up to 1.1.1.3 crypto/external/bsd/openssh/dist/PROTOCOL.krl up to 1.1.1.5 crypto/external/bsd/openssh/dist/PROTOCOL.mux up to 1.12 crypto/external/bsd/openssh/dist/addrmatch.c up to 1.15 crypto/external/bsd/openssh/dist/auth-krb5.c up to 1.16 crypto/external/bsd/openssh/dist/auth-options.c up to 1.29 crypto/external/bsd/openssh/dist/auth-options.h up to 1.15 crypto/external/bsd/openssh/dist/auth-pam.c up to 1.21 crypto/external/bsd/openssh/dist/auth-passwd.c up to 1.13 crypto/external/bsd/openssh/dist/auth-rhosts.c up to 1.16 crypto/external/bsd/openssh/dist/auth.c up to 1.34 crypto/external/bsd/openssh/dist/auth.h up to 1.23 crypto/external/bsd/openssh/dist/auth2-chall.c up to 1.19 crypto/external/bsd/openssh/dist/auth2-gss.c up to 1.17 crypto/external/bsd/openssh/dist/auth2-hostbased.c up to 1.23 crypto/external/bsd/openssh/dist/auth2-kbdint.c up to 1.15 crypto/external/bsd/openssh/dist/auth2-krb5.c up to 1.10 crypto/external/bsd/openssh/dist/auth2-none.c up to 1.14 crypto/external/bsd/openssh/dist/auth2-passwd.c up to 1.16 crypto/external/bsd/openssh/dist/auth2-pubkey.c up to 1.34 crypto/external/bsd/openssh/dist/auth2.c up to 1.29 crypto/external/bsd/openssh/dist/authfd.c up to 1.27 crypto/external/bsd/openssh/dist/authfd.h up to 1.17 crypto/external/bsd/openssh/dist/authfile.c up to 1.28 crypto/external/bsd/openssh/dist/authfile.h up to 1.10 crypto/external/bsd/openssh/dist/canohost.c up to 1.16 crypto/external/bsd/openssh/dist/chacha.c up to 1.6 crypto/external/bsd/openssh/dist/chacha.h up to 1.3 crypto/external/bsd/openssh/dist/channels.c up to 1.42 crypto/external/bsd/openssh/dist/channels.h up to 1.26 crypto/external/bsd/openssh/dist/cipher-chachapoly.c up to 1.7 crypto/external/bsd/openssh/dist/cipher-chachapoly.h up to 1.3 crypto/external/bsd/openssh/dist/cipher.c up to 1.21 crypto/external/bsd/openssh/dist/cipher.h up to 1.17 crypto/external/bsd/openssh/dist/clientloop.c up to 1.39 crypto/external/bsd/openssh/dist/clientloop.h up to 1.18 crypto/external/bsd/openssh/dist/compat.c up to 1.26 crypto/external/bsd/openssh/dist/compat.h up to 1.18 crypto/external/bsd/openssh/dist/crypto_api.h up to 1.5 crypto/external/bsd/openssh/dist/dh.c up to 1.20 crypto/external/bsd/openssh/dist/dh.h up to 1.13 crypto/external/bsd/openssh/dist/digest-libc.c up to 1.8 crypto/external/bsd/openssh/dist/digest-openssl.c up to 1.9 crypto/external/bsd/openssh/dist/dispatch.c up to 1.11 crypto/external/bsd/openssh/dist/dns.c up to 1.23 crypto/external/bsd/openssh/dist/dns.h up to 1.13 crypto/external/bsd/openssh/dist/ed25519.c up to 1.6 crypto/external/bsd/openssh/dist/fatal.c up to 1.7 crypto/external/bsd/openssh/dist/getrrsetbyname.c up to 1.6 crypto/external/bsd/openssh/dist/gss-genr.c up to 1.11 crypto/external/bsd/openssh/dist/gss-serv.c up to 1.15 crypto/external/bsd/openssh/dist/hash.c up to 1.7 crypto/external/bsd/openssh/dist/hmac.c up to 1.8 crypto/external/bsd/openssh/dist/hostfile.c up to 1.23 crypto/external/bsd/openssh/dist/hostfile.h up to 1.11 crypto/external/bsd/openssh/dist/includes.h up to 1.9 crypto/external/bsd/openssh/dist/kex.c up to 1.34 crypto/external/bsd/openssh/dist/kex.h up to 1.24 crypto/external/bsd/openssh/dist/kexdh.c up to 1.10 crypto/external/bsd/openssh/dist/kexgen.c up to 1.7 crypto/external/bsd/openssh/dist/kexgexc.c up to 1.17 crypto/external/bsd/openssh/dist/kexgexs.c up to 1.23 crypto/external/bsd/openssh/dist/krl.c up to 1.23 crypto/external/bsd/openssh/dist/krl.h up to 1.6 crypto/external/bsd/openssh/dist/ldapauth.c up to 1.8 crypto/external/bsd/openssh/dist/ldapauth.h up to 1.6 crypto/external/bsd/openssh/dist/log.c up to 1.27 crypto/external/bsd/openssh/dist/log.h up to 1.17 crypto/external/bsd/openssh/dist/mac.c up to 1.16 crypto/external/bsd/openssh/dist/match.c up to 1.16 crypto/external/bsd/openssh/dist/match.h up to 1.11 crypto/external/bsd/openssh/dist/misc.c up to 1.35 crypto/external/bsd/openssh/dist/misc.h up to 1.27 crypto/external/bsd/openssh/dist/moduli up to 1.10 crypto/external/bsd/openssh/dist/moduli.c up to 1.17 crypto/external/bsd/openssh/dist/monitor.c up to 1.43 crypto/external/bsd/openssh/dist/monitor.h up to 1.13 crypto/external/bsd/openssh/dist/monitor_fdpass.c up to 1.9 crypto/external/bsd/openssh/dist/monitor_wrap.c up to 1.34 crypto/external/bsd/openssh/dist/monitor_wrap.h up to 1.23 crypto/external/bsd/openssh/dist/msg.c up to 1.11 crypto/external/bsd/openssh/dist/mux.c up to 1.35 crypto/external/bsd/openssh/dist/myproposal.h up to 1.24 crypto/external/bsd/openssh/dist/namespace.h up to 1.10 crypto/external/bsd/openssh/dist/nchan.c up to 1.14 crypto/external/bsd/openssh/dist/packet.c up to 1.50 crypto/external/bsd/openssh/dist/packet.h up to 1.26 crypto/external/bsd/openssh/dist/pathnames.h up to 1.15 crypto/external/bsd/openssh/dist/pfilter.c up to 1.8 (+patch) crypto/external/bsd/openssh/dist/poly1305.c up to 1.6 crypto/external/bsd/openssh/dist/progressmeter.c up to 1.15 crypto/external/bsd/openssh/dist/readconf.c up to 1.44 crypto/external/bsd/openssh/dist/readconf.h up to 1.34 crypto/external/bsd/openssh/dist/readpass.c up to 1.18 crypto/external/bsd/openssh/dist/rijndael.h up to 1.3 crypto/external/bsd/openssh/dist/sandbox-pledge.c up to 1.3 crypto/external/bsd/openssh/dist/sandbox-rlimit.c up to 1.7 crypto/external/bsd/openssh/dist/scp.1 up to 1.31 crypto/external/bsd/openssh/dist/scp.c up to 1.41 crypto/external/bsd/openssh/dist/servconf.c up to 1.44 crypto/external/bsd/openssh/dist/servconf.h up to 1.30 crypto/external/bsd/openssh/dist/serverloop.c up to 1.35 crypto/external/bsd/openssh/dist/session.c up to 1.38 crypto/external/bsd/openssh/dist/session.h up to 1.10 crypto/external/bsd/openssh/dist/sftp-client.c up to 1.35 crypto/external/bsd/openssh/dist/sftp-client.h up to 1.18 crypto/external/bsd/openssh/dist/sftp-common.c up to 1.14 crypto/external/bsd/openssh/dist/sftp-common.h up to 1.8 crypto/external/bsd/openssh/dist/sftp-glob.c up to 1.15 crypto/external/bsd/openssh/dist/sftp-server-main.c up to 1.8 crypto/external/bsd/openssh/dist/sftp-server.8 up to 1.14 crypto/external/bsd/openssh/dist/sftp-server.c up to 1.30 crypto/external/bsd/openssh/dist/sftp.1 up to 1.30 crypto/external/bsd/openssh/dist/sftp.c up to 1.39 crypto/external/bsd/openssh/dist/ssh-add.1 up to 1.18 crypto/external/bsd/openssh/dist/ssh-add.c up to 1.30 crypto/external/bsd/openssh/dist/ssh-agent.1 up to 1.19 crypto/external/bsd/openssh/dist/ssh-agent.c up to 1.37 crypto/external/bsd/openssh/dist/ssh-dss.c up to 1.18 crypto/external/bsd/openssh/dist/ssh-ecdsa.c up to 1.15 crypto/external/bsd/openssh/dist/ssh-ed25519.c up to 1.10 crypto/external/bsd/openssh/dist/ssh-gss.h up to 1.10 crypto/external/bsd/openssh/dist/ssh-keygen.1 up to 1.34 crypto/external/bsd/openssh/dist/ssh-keygen.c up to 1.46 crypto/external/bsd/openssh/dist/ssh-keyscan.1 up to 1.18 crypto/external/bsd/openssh/dist/ssh-keyscan.c up to 1.32 crypto/external/bsd/openssh/dist/ssh-keysign.8 up to 1.14 crypto/external/bsd/openssh/dist/ssh-keysign.c up to 1.24 crypto/external/bsd/openssh/dist/ssh-pkcs11-client.c up to 1.19 crypto/external/bsd/openssh/dist/ssh-pkcs11-helper.8 up to 1.12 crypto/external/bsd/openssh/dist/ssh-pkcs11-helper.c up to 1.22 crypto/external/bsd/openssh/dist/ssh-pkcs11.c up to 1.26 crypto/external/bsd/openssh/dist/ssh-pkcs11.h up to 1.9 crypto/external/bsd/openssh/dist/ssh-rsa.c up to 1.19 crypto/external/bsd/openssh/dist/ssh-xmss.c up to 1.6 crypto/external/bsd/openssh/dist/ssh.1 up to 1.39 crypto/external/bsd/openssh/dist/ssh.c up to 1.45 crypto/external/bsd/openssh/dist/ssh.h up to 1.13 crypto/external/bsd/openssh/dist/ssh2.h up to 1.15 crypto/external/bsd/openssh/dist/ssh_api.c up to 1.15 crypto/external/bsd/openssh/dist/ssh_config up to 1.16 crypto/external/bsd/openssh/dist/ssh_config.5 up to 1.40 crypto/external/bsd/openssh/dist/sshbuf-getput-basic.c up to 1.12 crypto/external/bsd/openssh/dist/sshbuf-getput-crypto.c up to 1.11 crypto/external/bsd/openssh/dist/sshbuf-misc.c up to 1.14 crypto/external/bsd/openssh/dist/sshbuf.c up to 1.14 crypto/external/bsd/openssh/dist/sshbuf.h up to 1.19 crypto/external/bsd/openssh/dist/sshconnect.c up to 1.37 crypto/external/bsd/openssh/dist/sshconnect.h up to 1.17 crypto/external/bsd/openssh/dist/sshconnect2.c up to 1.46 crypto/external/bsd/openssh/dist/sshd.8 up to 1.31 crypto/external/bsd/openssh/dist/sshd.c up to 1.50 crypto/external/bsd/openssh/dist/sshd_config up to 1.28 crypto/external/bsd/openssh/dist/sshd_config.5 up to 1.42 crypto/external/bsd/openssh/dist/ssherr.c up to 1.10 crypto/external/bsd/openssh/dist/ssherr.h up to 1.4 crypto/external/bsd/openssh/dist/sshkey-xmss.c up to 1.10 crypto/external/bsd/openssh/dist/sshkey-xmss.h up to 1.5 crypto/external/bsd/openssh/dist/sshkey.c up to 1.32 crypto/external/bsd/openssh/dist/sshkey.h up to 1.19 crypto/external/bsd/openssh/dist/sshlogin.c up to 1.13 crypto/external/bsd/openssh/dist/sshpty.c up to 1.8 crypto/external/bsd/openssh/dist/ttymodes.c up to 1.12 crypto/external/bsd/openssh/dist/uidswap.c up to 1.10 crypto/external/bsd/openssh/dist/umac.c up to 1.22 crypto/external/bsd/openssh/dist/umac.h up to 1.10 crypto/external/bsd/openssh/dist/utf8.c up to 1.9 crypto/external/bsd/openssh/dist/utf8.h up to 1.5 crypto/external/bsd/openssh/dist/version.h up to 1.44 crypto/external/bsd/openssh/dist/xmalloc.c up to 1.13 crypto/external/bsd/openssh/dist/xmalloc.h up to 1.16 crypto/external/bsd/openssh/dist/xmss_hash.c up to 1.3 crypto/external/bsd/openssh/dist/moduli-gen/Makefile up to 1.3 crypto/external/bsd/openssh/dist/moduli-gen/moduli-gen.sh up to 1.1.1.3 crypto/external/bsd/openssh/dist/moduli-gen/moduli.2048 up to 1.16 crypto/external/bsd/openssh/dist/moduli-gen/moduli.3072 up to 1.18 crypto/external/bsd/openssh/dist/moduli-gen/moduli.4096 up to 1.18 crypto/external/bsd/openssh/dist/moduli-gen/moduli.6144 up to 1.18 crypto/external/bsd/openssh/dist/moduli-gen/moduli.7680 up to 1.18 crypto/external/bsd/openssh/dist/moduli-gen/moduli.8192 up to 1.18 crypto/external/bsd/openssh/lib/Makefile up to 1.38 crypto/external/bsd/openssh/lib/shlib_version up to 1.36 crypto/external/bsd/openssh/openssh2netbsd up to 1.4 lib/libpam/modules/pam_ssh/Makefile up to 1.13 lib/libpam/modules/pam_ssh/pam_ssh.c up to 1.30 distrib/sets/lists/base/shl.mi (apply patch) distrib/sets/lists/debug/shl.mi (apply patch) doc/3RDPARTY (apply patch) Update OpenSSH to 9.6.
Pull up the following revisions(s) (requested by martin in ticket #443): crypto/external/bsd/openssh/dist sync with HEAD crypto/external/bsd/openssh/dist/PROTOCOL: up to 1.22 crypto/external/bsd/openssh/dist/PROTOCOL.agent: up to 1.14 crypto/external/bsd/openssh/dist/PROTOCOL.krl: up to 1.1.1.5 crypto/external/bsd/openssh/dist/addr.c: up to 1.6 crypto/external/bsd/openssh/dist/auth-options.c: up to 1.29 crypto/external/bsd/openssh/dist/auth-pam.c: up to 1.21 crypto/external/bsd/openssh/dist/auth2-gss.c: up to 1.17 crypto/external/bsd/openssh/dist/auth2-pubkey.c: up to 1.34 crypto/external/bsd/openssh/dist/auth2.c: up to 1.28 crypto/external/bsd/openssh/dist/canohost.c: up to 1.16 crypto/external/bsd/openssh/dist/chacha.c: up to 1.6 crypto/external/bsd/openssh/dist/channels.c up to 1.41 crypto/external/bsd/openssh/dist/channels.h: up to 1.25 crypto/external/bsd/openssh/dist/cipher-chachapoly-libcrypto.c: up to 1.3 crypto/external/bsd/openssh/dist/cipher-chachapoly.c: up to 1.7 crypto/external/bsd/openssh/dist/clientloop.c: up to 1.38 crypto/external/bsd/openssh/dist/kex.c: up to 1.33 crypto/external/bsd/openssh/dist/kex.h: up to 1.23 crypto/external/bsd/openssh/dist/kexgexs.c: up to 1.23 crypto/external/bsd/openssh/dist/krl.c: up to 1.23 crypto/external/bsd/openssh/dist/krl.h: up to 1.6 crypto/external/bsd/openssh/dist/match.c: up to 1.16 crypto/external/bsd/openssh/dist/misc.c; up to 1.34 crypto/external/bsd/openssh/dist/misc.h: up to 1.26 crypto/external/bsd/openssh/dist/moduli: up to 1.10 crypto/external/bsd/openssh/dist/monitor.c: up to 1.43 crypto/external/bsd/openssh/dist/monitor_wrap.c: up to 1.33 crypto/external/bsd/openssh/dist/mux.c: up to 1.34 crypto/external/bsd/openssh/dist/packet.c: up to 1.49 crypto/external/bsd/openssh/dist/packet.h: up to 1.25 crypto/external/bsd/openssh/dist/poly1305.c: up to 1.6 crypto/external/bsd/openssh/dist/progressmeter.c: up to 1.15 crypto/external/bsd/openssh/dist/readconf.c: up to 1.42 crypto/external/bsd/openssh/dist/readconf.h: up to 1.32 crypto/external/bsd/openssh/dist/scp.c: up to 1.40 crypto/external/bsd/openssh/dist/servconf.c: up to 1.43 crypto/external/bsd/openssh/dist/servconf.h: up to 1.30 crypto/external/bsd/openssh/dist/serverloop.c: up to 1.35 crypto/external/bsd/openssh/dist/session.c: up to 1.38 crypto/external/bsd/openssh/dist/sftp-client.c: up to 1.34 crypto/external/bsd/openssh/dist/sftp-client.h: up to 1.18 crypto/external/bsd/openssh/dist/sftp-common.c: up to 1.14 crypto/external/bsd/openssh/dist/sftp-glob.c: up to 1.15 crypto/external/bsd/openssh/dist/sftp-server.c: up to 1.30 crypto/external/bsd/openssh/dist/sftp-usergroup.c: up to 1.3 crypto/external/bsd/openssh/dist/sftp.c: up to 1.39 crypto/external/bsd/openssh/dist/sk-usbhid.c: up to 1.9 crypto/external/bsd/openssh/dist/ssh-add.c: up to 1.29 crypto/external/bsd/openssh/dist/ssh-agent.1: up to 1.19 crypto/external/bsd/openssh/dist/ssh-agent.c: up to 1.36 crypto/external/bsd/openssh/dist/ssh-keygen.1: up to 1.34 crypto/external/bsd/openssh/dist/ssh-keygen.c: up to 1.46 crypto/external/bsd/openssh/dist/ssh-keyscan.c: up to 1.32 crypto/external/bsd/openssh/dist/ssh-pkcs11-client.c: up to 1.18 crypto/external/bsd/openssh/dist/ssh-pkcs11.c: up to 1.26 crypto/external/bsd/openssh/dist/ssh-sk.c: up to 1.8 crypto/external/bsd/openssh/dist/ssh.1: up to 1.37 crypto/external/bsd/openssh/dist/ssh.c: up to 1.44 crypto/external/bsd/openssh/dist/ssh2.h: up to 1.14 crypto/external/bsd/openssh/dist/ssh_config: up to 1.16 crypto/external/bsd/openssh/dist/ssh_config.5: up to 1.38 crypto/external/bsd/openssh/dist/sshconnect2.c: up to 1.45 crypto/external/bsd/openssh/dist/sshd.8: up to 1.31 crypto/external/bsd/openssh/dist/sshd_config.5: up to 1.42 crypto/external/bsd/openssh/dist/sshkey.c: up to 1.31 crypto/external/bsd/openssh/dist/sshkey.h: up to 1.19 crypto/external/bsd/openssh/dist/sshsig.c: up to 1.11 crypto/external/bsd/openssh/dist/version.h: up to 1.43 crypto/external/bsd/openssh/dist/moduli-gen/moduli.2048: up to 1.15 crypto/external/bsd/openssh/dist/moduli-gen/moduli.3072: up to 1.17 crypto/external/bsd/openssh/dist/moduli-gen/moduli.4096: up to 1.17 crypto/external/bsd/openssh/dist/moduli-gen/moduli.6144: up to 1.17 crypto/external/bsd/openssh/dist/moduli-gen/moduli.7680: up to 1.17 crypto/external/bsd/openssh/dist/moduli-gen/moduli.8192: up to 1.17 crypto/external/bsd/openssh/lib/shlib_version: 1.35 distrib/sets/lists/base/shl.mi: 1.972 via patch distrib/sets/lists/debug/shl.mi: 1.333 doc/3RDPARTY: 1.1962 via patch ssh(1): update to OpenSSH 9.5
file ssh-sk.c was added on branch netbsd-9 on 2023-12-25 12:31:08 +0000
Merge conflicts between 9.3 and 9.5
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
merge conflicts between 9.0 and 9.1
Import OpenSSH-9.1 (previously we were on OpenSSH-9.0) 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.
Merge differences between openssh-8.8 and openssh-8.9
Import OpenSSH 8.9. 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.
merge local changes between openssh 8.4 and 8.5
OpenSSH 8.5/8.5p1 (2021-03-03)
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
Merge conflicts
OpenSSH 8.4 was released on 2020-09-27. 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. 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
Merge conflicts
OpenSSH 8.3 was released on 2020-05-27. 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. 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.
A future release of OpenSSH will enable UpdateHostKeys by default
to allow the client to automatically migrate to better algorithms.
Users may consider enabling this option manually. Vendors of devices
that implement the SSH protocol should ensure that they support the
new signature algorithms for RSA keys.
[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
========
* scp(1): when receiving files, scp(1) could be become desynchronised
if a utimes(2) system call failed. This could allow file contents
to be interpreted as file metadata and thereby permit an adversary
to craft a file system that, when copied with scp(1) in a
configuration that caused utimes(2) to fail (e.g. under a SELinux
policy or syscall sandbox), transferred different file names and
contents to the actual file system layout.
Exploitation of this is not likely as utimes(2) does not fail under
normal circumstances. Successful exploitation is not silent - the
output of scp(1) would show transfer errors followed by the actual
file(s) that were received.
Finally, filenames returned from the peer are (since openssh-8.0)
matched against the user's requested destination, thereby
disallowing a successful exploit from writing files outside the
user's selected target glob (or directory, in the case of a
recursive transfer). This ensures that this attack can achieve no
more than a hostile peer is already able to achieve within the scp
protocol.
Potentially-incompatible changes
================================
This release includes a number of changes that may affect existing
configurations:
* sftp(1): reject an argument of "-1" in the same way as ssh(1) and
scp(1) do instead of accepting and silently ignoring it.
Changes since OpenSSH 8.2
=========================
The focus of this release is bug fixing.
New Features
------------
* sshd(8): make IgnoreRhosts a tri-state option: "yes" to ignore
rhosts/shosts, "no" allow rhosts/shosts or (new) "shosts-only"
to allow .shosts files but not .rhosts.
* sshd(8): allow the IgnoreRhosts directive to appear anywhere in a
sshd_config, not just before any Match blocks; bz3148
* ssh(1): add %TOKEN percent expansion for the LocalFoward and
RemoteForward keywords when used for Unix domain socket forwarding.
bz#3014
* all: allow loading public keys from the unencrypted envelope of a
private key file if no corresponding public key file is present.
* ssh(1), sshd(8): prefer to use chacha20 from libcrypto where
possible instead of the (slower) portable C implementation included
in OpenSSH.
* ssh-keygen(1): add ability to dump the contents of a binary key
revocation list via "ssh-keygen -lQf /path" bz#3132
Bugfixes
--------
* ssh(1): fix IdentitiesOnly=yes to also apply to keys loaded from
a PKCS11Provider; bz#3141
* ssh-keygen(1): avoid NULL dereference when trying to convert an
invalid RFC4716 private key.
* scp(1): when performing remote-to-remote copies using "scp -3",
start the second ssh(1) channel with BatchMode=yes enabled to
avoid confusing and non-deterministic ordering of prompts.
* ssh(1), ssh-keygen(1): when signing a challenge using a FIDO token,
perform hashing of the message to be signed in the middleware layer
rather than in OpenSSH code. This permits the use of security key
middlewares that perform the hashing implicitly, such as Windows
Hello.
* ssh(1): fix incorrect error message for "too many known hosts
files." bz#3149
* ssh(1): make failures when establishing "Tunnel" forwarding
terminate the connection when ExitOnForwardFailure is enabled;
bz#3116
* ssh-keygen(1): fix printing of fingerprints on private keys and add
a regression test for same.
* sshd(8): document order of checking AuthorizedKeysFile (first) and
AuthorizedKeysCommand (subsequently, if the file doesn't match);
bz#3134
* sshd(8): document that /etc/hosts.equiv and /etc/shosts.equiv are
not considered for HostbasedAuthentication when the target user is
root; bz#3148
* ssh(1), ssh-keygen(1): fix NULL dereference in private certificate
key parsing (oss-fuzz #20074).
* ssh(1), sshd(8): more consistency between sets of %TOKENS are
accepted in various configuration options.
* ssh(1), ssh-keygen(1): improve error messages for some common
PKCS#11 C_Login failure cases; bz#3130
* ssh(1), sshd(8): make error messages for problems during SSH banner
exchange consistent with other SSH transport-layer error messages
and ensure they include the relevant IP addresses bz#3129
* various: fix a number of spelling errors in comments and debug/error
messages
* ssh-keygen(1), ssh-add(1): when downloading FIDO2 resident keys
from a token, don't prompt for a PIN until the token has told us
that it needs one. Avoids double-prompting on devices that
implement on-device authentication.
* sshd(8), ssh-keygen(1): no-touch-required FIDO certificate option
should be an extension, not a critical option.
* ssh(1), ssh-keygen(1), ssh-add(1): offer a better error message
when trying to use a FIDO key function and SecurityKeyProvider is
empty.
* ssh-add(1), ssh-agent(8): ensure that a key lifetime fits within
the values allowed by the wire format (u32). Prevents integer
wraparound of the timeout values. bz#3119
* ssh(1): detect and prevent trivial configuration loops when using
ProxyJump. bz#3057.
Portability
-----------
* Detect systems where signals flagged with SA_RESTART will interrupt
select(2). POSIX permits implementations to choose whether
select(2) will return when interrupted with a SA_RESTART-flagged
signal, but OpenSSH requires interrupting behaviour.
* Several compilation fixes for HP/UX and AIX.
* On platforms that do not support setting process-wide routing
domains (all excepting OpenBSD at present), fail to accept a
configuration attempts to set one at process start time rather than
fatally erroring at run time. bz#3126
* Improve detection of egrep (used in regression tests) on platforms
that offer a poor default one (e.g. Solaris).
* A number of shell portability fixes for the regression tests.
* Fix theoretical infinite loop in the glob(3) replacement
implementation.
* Fix seccomp sandbox compilation problems for some Linux
configurations bz#3085
* Improved detection of libfido2 and some compilation fixes for some
configurations when --with-security-key-builtin is selected.
Merge changes from current as of 20200406
file ssh-sk.c was added on branch phil-wifi on 2020-04-08 14:03:18 +0000
Merge conflicts
OpenSSH 8.2/8.2p1 (2020-02-14)
OpenSSH 8.2 was released on 2020-02-14. 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 hash algorithm for less than USD$50K. For this reason, we will
be disabling the "ssh-rsa" public key signature algorithm that depends
on SHA-1 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.
A future release of OpenSSH will enable UpdateHostKeys by default
to allow the client to automatically migrate 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(1), sshd(8), ssh-keygen(1): this release removes the "ssh-rsa"
(RSA/SHA1) algorithm from those accepted for certificate signatures
(i.e. the client and server CASignatureAlgorithms option) and will
use the rsa-sha2-512 signature algorithm by default when the
ssh-keygen(1) CA signs new certificates.
Certificates are at special risk to the aforementioned SHA1
collision vulnerability as an attacker has effectively unlimited
time in which to craft a collision that yields them a valid
certificate, far more than the relatively brief LoginGraceTime
window that they have to forge a host key signature.
The OpenSSH certificate format includes a CA-specified (typically
random) nonce value near the start of the certificate that should
make exploitation of chosen-prefix collisions in this context
challenging, as the attacker does not have full control over the
prefix that actually gets signed. Nonetheless, SHA1 is now a
demonstrably broken algorithm and futher improvements in attacks
are highly likely.
OpenSSH releases prior to 7.2 do not support the newer RSA/SHA2
algorithms and will refuse to accept certificates signed by an
OpenSSH 8.2+ CA using RSA keys unless the unsafe algorithm is
explicitly selected during signing ("ssh-keygen -t ssh-rsa").
Older clients/servers may use another CA key type such as
ssh-ed25519 (supported since OpenSSH 6.5) or one of the
ecdsa-sha2-nistp256/384/521 types (supported since OpenSSH 5.7)
instead if they cannot be upgraded.
Potentially-incompatible changes
================================
This release includes a number of changes that may affect existing
configurations:
* ssh(1), sshd(8): the above removal of "ssh-rsa" from the accepted
CASignatureAlgorithms list.
* ssh(1), sshd(8): this release removes diffie-hellman-group14-sha1
from the default key exchange proposal for both the client and
server.
* ssh-keygen(1): the command-line options related to the generation
and screening of safe prime numbers used by the
diffie-hellman-group-exchange-* key exchange algorithms have
changed. Most options have been folded under the -O flag.
* sshd(8): the sshd listener process title visible to ps(1) has
changed to include information about the number of connections that
are currently attempting authentication and the limits configured
by MaxStartups.
* ssh-sk-helper(8): this is a new binary. It is used by the FIDO/U2F
support to provide address-space isolation for token middleware
libraries (including the internal one). It needs to be installed
in the expected path, typically under /usr/libexec or similar.
Changes since OpenSSH 8.1
=========================
This release contains some significant new features.
FIDO/U2F Support
----------------
This release adds support for FIDO/U2F hardware authenticators to
OpenSSH. U2F/FIDO are open standards for inexpensive two-factor
authentication hardware that are widely used for website
authentication. In OpenSSH FIDO devices are supported by new public
key types "ecdsa-sk" and "ed25519-sk", along with corresponding
certificate types.
ssh-keygen(1) may be used to generate a FIDO token-backed key, after
which they may be used much like any other key type supported by
OpenSSH, so long as the hardware token is attached when the keys are
used. FIDO tokens also generally require the user explicitly authorise
operations by touching or tapping them.
Generating a FIDO key requires the token be attached, and will usually
require the user tap the token to confirm the operation:
$ ssh-keygen -t ecdsa-sk -f ~/.ssh/id_ecdsa_sk
Generating public/private ecdsa-sk key pair.
You may need to touch your security key to authorize key generation.
Enter file in which to save the key (/home/djm/.ssh/id_ecdsa_sk):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/djm/.ssh/id_ecdsa_sk
Your public key has been saved in /home/djm/.ssh/id_ecdsa_sk.pub
This will yield a public and private key-pair. The private key file
should be useless to an attacker who does not have access to the
physical token. After generation, this key may be used like any other
supported key in OpenSSH and may be listed in authorized_keys, added
to ssh-agent(1), etc. The only additional stipulation is that the FIDO
token that the key belongs to must be attached when the key is used.
FIDO tokens are most commonly connected via USB but may be attached
via other means such as Bluetooth or NFC. In OpenSSH, communication
with the token is managed via a middleware library, specified by the
SecurityKeyProvider directive in ssh/sshd_config(5) or the
$SSH_SK_PROVIDER environment variable for ssh-keygen(1) and
ssh-add(1). The API for this middleware is documented in the sk-api.h
and PROTOCOL.u2f files in the source distribution.
OpenSSH includes a middleware ("SecurityKeyProvider=internal") with
support for USB tokens. It is automatically enabled in OpenBSD and may
be enabled in portable OpenSSH via the configure flag
--with-security-key-builtin. If the internal middleware is enabled
then it is automatically used by default. This internal middleware
requires that libfido2 (https://github.com/Yubico/libfido2) and its
dependencies be installed. We recommend that packagers of portable
OpenSSH enable the built-in middleware, as it provides the
lowest-friction experience for users.
Note: FIDO/U2F tokens are required to implement the ECDSA-P256
"ecdsa-sk" key type, but hardware support for Ed25519 "ed25519-sk" is
less common. Similarly, not all hardware tokens support some of the
optional features such as resident keys.
The protocol-level changes to support FIDO/U2F keys in SSH are
documented in the PROTOCOL.u2f file in the OpenSSH source
distribution.
There are a number of supporting changes to this feature:
* ssh-keygen(1): add a "no-touch-required" option when generating
FIDO-hosted keys, that disables their default behaviour of
requiring a physical touch/tap on the token during authentication.
Note: not all tokens support disabling the touch requirement.
* sshd(8): add a sshd_config PubkeyAuthOptions directive that
collects miscellaneous public key authentication-related options
for sshd(8). At present it supports only a single option
"no-touch-required". This causes sshd to skip its default check for
FIDO/U2F keys that the signature was authorised by a touch or press
event on the token hardware.
* ssh(1), sshd(8), ssh-keygen(1): add a "no-touch-required" option
for authorized_keys and a similar extension for certificates. This
option disables the default requirement that FIDO key signatures
attest that the user touched their key to authorize them, mirroring
the similar PubkeyAuthOptions sshd_config option.
* ssh-keygen(1): add support for the writing the FIDO attestation
information that is returned when new keys are generated via the
"-O write-attestation=/path" option. FIDO attestation certificates
may be used to verify that a FIDO key is hosted in trusted
hardware. OpenSSH does not currently make use of this information,
beyond optionally writing it to disk.
FIDO2 resident keys
-------------------
FIDO/U2F OpenSSH keys consist of two parts: a "key handle" part stored
in the private key file on disk, and a per-device private key that is
unique to each FIDO/U2F token and that cannot be exported from the
token hardware. These are combined by the hardware at authentication
time to derive the real key that is used to sign authentication
challenges.
For tokens that are required to move between computers, it can be
cumbersome to have to move the private key file first. To avoid this
requirement, tokens implementing the newer FIDO2 standard support
"resident keys", where it is possible to effectively retrieve the key
handle part of the key from the hardware.
OpenSSH supports this feature, allowing resident keys to be generated
using the ssh-keygen(1) "-O resident" flag. This will produce a
public/private key pair as usual, but it will be possible to retrieve
the private key part from the token later. This may be done using
"ssh-keygen -K", which will download all available resident keys from
the tokens attached to the host and write public/private key files
for them. It is also possible to download and add resident keys
directly to ssh-agent(1) without writing files to the file-system
using "ssh-add -K".
Resident keys are indexed on the token by the application string and
user ID. By default, OpenSSH uses an application string of "ssh:" and
an empty user ID. If multiple resident keys on a single token are
desired then it may be necessary to override one or both of these
defaults using the ssh-keygen(1) "-O application=" or "-O user="
options. Note: OpenSSH will only download and use resident keys whose
application string begins with "ssh:"
Storing both parts of a key on a FIDO token increases the likelihood
of an attacker being able to use a stolen token device. For this
reason, tokens should enforce PIN authentication before allowing
download of keys, and users should set a PIN on their tokens before
creating any resident keys.
Other New Features
------------------
* sshd(8): add an Include sshd_config keyword that allows including
additional configuration files via glob(3) patterns. bz2468
* ssh(1)/sshd(8): make the LE (low effort) DSCP code point available
via the IPQoS directive; bz2986,
* ssh(1): when AddKeysToAgent=yes is set and the key contains no
comment, add the key to the agent with the key's path as the
comment. bz2564
* ssh-keygen(1), ssh-agent(1): expose PKCS#11 key labels and X.509
subjects as key comments, rather than simply listing the PKCS#11
provider library path. PR138
* ssh-keygen(1): allow PEM export of DSA and ECDSA keys; bz3091
* ssh(1), sshd(8): make zlib compile-time optional, available via the
Makefile.inc ZLIB flag on OpenBSD or via the --with-zlib configure
option for OpenSSH portable.
* sshd(8): when clients get denied by MaxStartups, send a
notification prior to the SSH2 protocol banner according to
RFC4253 section 4.2.
* ssh(1), ssh-agent(1): when invoking the $SSH_ASKPASS prompt
program, pass a hint to the program to describe the type of
desired prompt. The possible values are "confirm" (indicating
that a yes/no confirmation dialog with no text entry should be
shown), "none" (to indicate an informational message only), or
blank for the original ssh-askpass behaviour of requesting a
password/phrase.
* ssh(1): allow forwarding a different agent socket to the path
specified by $SSH_AUTH_SOCK, by extending the existing ForwardAgent
option to accepting an explicit path or the name of an environment
variable in addition to yes/no.
* ssh-keygen(1): add a new signature operations "find-principals" to
look up the principal associated with a signature from an allowed-
signers file.
* sshd(8): expose the number of currently-authenticating connections
along with the MaxStartups limit in the process title visible to
"ps".
Bugfixes
--------
* sshd(8): make ClientAliveCountMax=0 have sensible semantics: it
will now disable connection killing entirely rather than the
current behaviour of instantly killing the connection after the
first liveness test regardless of success. bz2627
* sshd(8): clarify order of AllowUsers / DenyUsers vs AllowGroups /
DenyGroups in the sshd(8) manual page. bz1690
* sshd(8): better describe HashKnownHosts in the manual page. bz2560
* sshd(8): clarify that that permitopen=/PermitOpen do no name or
address translation in the manual page. bz3099
* sshd(8): allow the UpdateHostKeys feature to function when
multiple known_hosts files are in use. When updating host keys,
ssh will now search subsequent known_hosts files, but will add
updated host keys to the first specified file only. bz2738
* All: replace all calls to signal(2) with a wrapper around
sigaction(2). This wrapper blocks all other signals during the
handler preventing races between handlers, and sets SA_RESTART
which should reduce the potential for short read/write operations.
* sftp(1): fix a race condition in the SIGCHILD handler that could
turn in to a kill(-1); bz3084
* sshd(8): fix a case where valid (but extremely large) SSH channel
IDs were being incorrectly rejected. bz3098
* ssh(1): when checking host key fingerprints as answers to new
hostkey prompts, ignore whitespace surrounding the fingerprint
itself.
* All: wait for file descriptors to be readable or writeable during
non-blocking connect, not just readable. Prevents a timeout when
the server doesn't immediately send a banner (e.g. multiplexers
like sslh)
* sshd_config(5): document the sntrup4591761x25519-sha512@tinyssh.org
key exchange algorithm. PR#151
Initial revision