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2018-08-24Add DebianBanner server configuration optionKees Cook
Setting this to "no" causes sshd to omit the Debian revision from its initial protocol handshake, for those scared by package-versioning.patch. Bug-Debian: http://bugs.debian.org/562048 Forwarded: not-needed Last-Update: 2018-08-24 Patch-Name: debian-banner.patch
2018-08-24Include the Debian version in our identificationMatthew Vernon
This makes it easier to audit networks for versions patched against security vulnerabilities. It has little detrimental effect, as attackers will generally just try attacks rather than bothering to scan for vulnerable-looking version strings. (However, see debian-banner.patch.) Forwarded: not-needed Last-Update: 2017-10-04 Patch-Name: package-versioning.patch
2018-08-24Handle SELinux authorisation rolesManoj Srivastava
Rejected upstream due to discomfort with magic usernames; a better approach will need an SSH protocol change. In the meantime, this came from Debian's SELinux maintainer, so we'll keep it until we have something better. Bug: https://bugzilla.mindrot.org/show_bug.cgi?id=1641 Bug-Debian: http://bugs.debian.org/394795 Last-Update: 2018-08-24 Patch-Name: selinux-role.patch
2018-08-24Restore TCP wrappers supportColin Watson
Support for TCP wrappers was dropped in OpenSSH 6.7. See this message and thread: https://lists.mindrot.org/pipermail/openssh-unix-dev/2014-April/032497.html It is true that this reduces preauth attack surface in sshd. On the other hand, this support seems to be quite widely used, and abruptly dropping it (from the perspective of users who don't read openssh-unix-dev) could easily cause more serious problems in practice. It's not entirely clear what the right long-term answer for Debian is, but it at least probably doesn't involve dropping this feature shortly before a freeze. Forwarded: not-needed Last-Update: 2018-08-24 Patch-Name: restore-tcp-wrappers.patch
2018-08-24GSSAPI key exchange supportSimon Wilkinson
This patch has been rejected upstream: "None of the OpenSSH developers are in favour of adding this, and this situation has not changed for several years. This is not a slight on Simon's patch, which is of fine quality, but just that a) we don't trust GSSAPI implementations that much and b) we don't like adding new KEX since they are pre-auth attack surface. This one is particularly scary, since it requires hooks out to typically root-owned system resources." However, quite a lot of people rely on this in Debian, and it's better to have it merged into the main openssh package rather than having separate -krb5 packages (as we used to have). It seems to have a generally good security history. Bug: https://bugzilla.mindrot.org/show_bug.cgi?id=1242 Last-Updated: 2018-08-24 Patch-Name: gssapi.patch
2018-08-13upstream: revert compat.[ch] section of the following change. Itdjm@openbsd.org
causes double-free under some circumstances. -- date: 2018/07/31 03:07:24; author: djm; state: Exp; lines: +33 -18; commitid: f7g4UI8eeOXReTPh; fix some memory leaks spotted by Coverity via Jakub Jelen in bz#2366 feedback and ok dtucker@ OpenBSD-Commit-ID: 1e77547f60fdb5e2ffe23e2e4733c54d8d2d1137
2018-07-31upstream: fix some memory leaks spotted by Coverity via Jakub Jelendjm@openbsd.org
in bz#2366 feedback and ok dtucker@ OpenBSD-Commit-ID: 8402bbae67d578bedbadb0ce68ff7c5a136ef563
2018-07-12upstream: remove legacy key emulation layer; ok djm@markus@openbsd.org
OpenBSD-Commit-ID: 2b1f9619259e222bbd4fe9a8d3a0973eafb9dd8d
2018-07-10Adapt portable to legacy buffer API removalDamien Miller
2018-07-10upstream: sshd: switch config to sshbuf API; ok djm@markus@openbsd.org
OpenBSD-Commit-ID: 72b02017bac7feac48c9dceff8355056bea300bd
2018-07-10upstream: sshd: switch loginmsg to sshbuf API; ok djm@markus@openbsd.org
OpenBSD-Commit-ID: f3cb4e54bff15c593602d95cc43e32ee1a4bac42
2018-07-03upstream: Improve strictness and control over RSA-SHA2 signaturedjm@openbsd.org
In ssh, when an agent fails to return a RSA-SHA2 signature when requested and falls back to RSA-SHA1 instead, retry the signature to ensure that the public key algorithm sent in the SSH_MSG_USERAUTH matches the one in the signature itself. In sshd, strictly enforce that the public key algorithm sent in the SSH_MSG_USERAUTH message matches what appears in the signature. Make the sshd_config PubkeyAcceptedKeyTypes and HostbasedAcceptedKeyTypes options control accepted signature algorithms (previously they selected supported key types). This allows these options to ban RSA-SHA1 in favour of RSA-SHA2. Add new signature algorithms "rsa-sha2-256-cert-v01@openssh.com" and "rsa-sha2-512-cert-v01@openssh.com" to force use of RSA-SHA2 signatures with certificate keys. feedback and ok markus@ OpenBSD-Commit-ID: c6e9f6d45eed8962ad502d315d7eaef32c419dde
2018-04-13upstream: Defend against user enumeration timing attacks. Thisdtucker@openbsd.org
establishes a minimum time for each failed authentication attempt (5ms) and adds a per-user constant derived from a host secret (0-4ms). Based on work by joona.kannisto at tut.fi, ok markus@ djm@. OpenBSD-Commit-ID: b7845b355bb7381703339c8fb0e57e81a20ae5ca
2018-04-10upstream: lots of typos in comments/docs. Patch from Karsten Weissdjm@openbsd.org
after checking with codespell tool (https://github.com/lucasdemarchi/codespell) OpenBSD-Commit-ID: 373222f12d7ab606598a2d36840c60be93568528
2018-03-03upstream: switch over to the new authorized_keys options API anddjm@openbsd.org
remove the legacy one. Includes a fairly big refactor of auth2-pubkey.c to retain less state between key file lines. feedback and ok markus@ OpenBSD-Commit-ID: dece6cae0f47751b9892080eb13d6625599573df
2018-02-26upstream: Add experimental support for PQC XMSS keys (Extendedmarkus@openbsd.org
Hash-Based Signatures) The code is not compiled in by default (see WITH_XMSS in Makefile.inc) Joint work with stefan-lukas_gazdag at genua.eu See https://tools.ietf.org/html/draft-irtf-cfrg-xmss-hash-based-signatures-12 ok djm@ OpenBSD-Commit-ID: ef3eccb96762a5d6f135d7daeef608df7776a7ac
2018-02-15Remove UNICOS support.Darren Tucker
The code required to support it is quite invasive to the mainline code that is synced with upstream and is an ongoing maintenance burden. Both the hardware and software are literal museum pieces these days and we could not find anyone still running OpenSSH on one.
2018-02-13upstream Don't reset signal handlers inside handlers.dtucker@openbsd.org
The signal handlers from the original ssh1 code on which OpenSSH is based assume unreliable signals and reinstall their handlers. Since OpenBSD (and pretty much every current system) has reliable signals this is not needed. In the unlikely even that -portable is still being used on such systems we will deal with it in the compat layer. ok deraadt@ OpenBSD-Commit-ID: f53a1015cb6908431b92116130d285d71589612c
2018-01-24upstream commitstsp@openbsd.org
Fix a logic bug in sshd_exchange_identification which prevented clients using major protocol version 2 from connecting to the server. ok millert@ OpenBSD-Commit-ID: 8668dec04586e27f1c0eb039ef1feb93d80a5ee9
2018-01-23upstream commitdjm@openbsd.org
Drop compatibility hacks for some ancient SSH implementations, including ssh.com <=2.* and OpenSSH <= 3.*. These versions were all released in or before 2001 and predate the final SSH RFCs. The hacks in question aren't necessary for RFC- compliant SSH implementations. ok markus@ OpenBSD-Commit-ID: 4be81c67db57647f907f4e881fb9341448606138
2018-01-23upstream commitdjm@openbsd.org
unbreak support for clients that advertise a protocol version of "1.99" (indicating both v2 and v1 support). Busted by me during SSHv1 purge in r1.358; bz2810, ok dtucker OpenBSD-Commit-ID: e8f9c2bee11afc16c872bb79d6abe9c555bd0e4b
2018-01-23upstream commitdjm@openbsd.org
avoid modifying pw->pw_passwd; let endpwent() clean up for us, but keep a scrubbed copy; bz2777, ok dtucker@ OpenBSD-Commit-ID: 715afc0f59c6b82c4929a73279199ed241ce0752
2017-11-14upstream commitdjm@openbsd.org@openbsd.org
fix problem in configuration parsing when in config dump mode (sshd -T) without providing a full connection specification (sshd -T -C ...) spotted by bluhm@ OpenBSD-Commit-ID: 7125faf5740eaa9d3a2f25400a0bc85e94e28b8f
2017-11-03upstream commitdtucker@openbsd.org@openbsd.org
When doing a config test with sshd -T, only require the attributes that are actually used in Match criteria rather than (an incomplete list of) all criteria. ok djm@, man page help jmc@ OpenBSD-Commit-ID: b4e773c4212d3dea486d0259ae977551aab2c1fc
2017-10-31upstream commitdjm@openbsd.org@openbsd.org
improve printing of rdomain on accept() a little OpenBSD-Commit-ID: 5da58db2243606899cedaa646c70201b2d12247a
2017-10-25provide hooks and fallbacks for rdomain supportDamien Miller
2017-10-25upstream commitdjm@openbsd.org
add a "rdomain" criteria for the sshd_config Match keyword to allow conditional configuration that depends on which rdomain(4) a connection was recevied on. ok markus@ Upstream-ID: 27d8fd5a3f1bae18c9c6e533afdf99bff887a4fb
2017-10-25upstream commitdjm@openbsd.org
add sshd_config RDomain keyword to place sshd and the subsequent user session (including the shell and any TCP/IP forwardings) into the specified rdomain(4) ok markus@ Upstream-ID: be2358e86346b5cacf20d90f59f980b87d1af0f5
2017-10-25upstream commitdjm@openbsd.org
Add optional rdomain qualifier to sshd_config's ListenAddress option to allow listening on a different rdomain(4), e.g. ListenAddress 0.0.0.0 rdomain 4 Upstream-ID: 24b6622c376feeed9e9be8b9605e593695ac9091
2017-10-23avoid -Wsign-compare warning in argv copyingDamien Miller
2017-10-20upstream commitdjm@openbsd.org
replace statically-sized arrays in ServerOptions with dynamic ones managed by xrecallocarray, removing some arbitrary (though large) limits and saving a bit of memory; "much nicer" markus@ Upstream-ID: 1732720b2f478fe929d6687ac7b0a97ff2efe9d2
2017-09-12upstream commitdjm@openbsd.org
refactor channels.c Move static state to a "struct ssh_channels" that is allocated at runtime and tracked as a member of struct ssh. Explicitly pass "struct ssh" to all channels functions. Replace use of the legacy packet APIs in channels.c. Rework sshd_config PermitOpen handling: previously the configuration parser would call directly into the channels layer. After the refactor this is not possible, as the channels structures are allocated at connection time and aren't available when the configuration is parsed. The server config parser now tracks PermitOpen itself and explicitly configures the channels code later. ok markus@ Upstream-ID: 11828f161656b965cc306576422613614bea2d8f
2017-07-21upstream commitdjm@openbsd.org
remove post-SSHv1 removal dead code from rsa.c and merge the remaining bit that it still used into ssh-rsa.c; ok markus Upstream-ID: ac8a048d24dcd89594b0052ea5e3404b473bfa2f
2017-06-01upstream commitmarkus@openbsd.org
clear session keys from memory; ok djm@ Upstream-ID: ecd178819868975affd5fd6637458b7c712b6a0f
2017-06-01upstream commitmarkus@openbsd.org
remove now obsolete ctx from ssh_dispatch_run; ok djm@ Upstream-ID: 9870aabf7f4d71660c31fda91b942b19a8e68d29
2017-05-31upstream commitmarkus@openbsd.org
switch from Key typedef with struct sshkey; ok djm@ Upstream-ID: 3067d33e04efbe5131ce8f70668c47a58e5b7a1f
2017-05-01upstream commitdjm@openbsd.org
remove KEY_RSA1 ok markus@ Upstream-ID: 7408517b077c892a86b581e19f82a163069bf133
2017-05-01upstream commitdjm@openbsd.org
remove compat20/compat13/compat15 variables ok markus@ Upstream-ID: 43802c035ceb3fef6c50c400e4ecabf12354691c
2017-03-29Don't check privsep user or path when unprivilegedDarren Tucker
If running with privsep (mandatory now) as a non-privileged user, we don't chroot or change to an unprivileged user however we still checked the existence of the user and directory. Don't do those checks if we're not going to use them. Based in part on a patch from Lionel Fourquaux via Corinna Vinschen, ok djm@
2017-03-15upstream commitderaadt@openbsd.org
accidents happen to the best of us; ok djm Upstream-ID: b7a9dbd71011ffde95e06f6945fe7197dedd1604
2017-03-15upstream commitdjm@openbsd.org
Fix segfault when sshd attempts to load RSA1 keys (can only happen when protocol v.1 support is enabled for the client). Reported by Jakub Jelen in bz#2686; ok dtucker Upstream-ID: 8fdaec2ba4b5f65db1d094f6714ce64b25d871d7
2017-02-28upstream commitdjm@openbsd.org
might as well set the listener socket CLOEXEC Upstream-ID: 9c538433d6a0ca79f5f21decc5620e46fb68ab57
2017-02-06upstream commitdjm@openbsd.org
Restore \r\n newline sequence for server ident string. The CR got lost in the flensing of SSHv1. Pointed out by Stef Bon Upstream-ID: 5333fd43ce5396bf5999496096fac5536e678fac
2017-02-03upstream commitdtucker@openbsd.org
Make ssh_packet_set_rekey_limits take u32 for the number of seconds until rekeying (negative values are rejected at config parse time). This allows the removal of some casts and a signed vs unsigned comparison warning. rekey_time is cast to int64 for the comparison which is a no-op on OpenBSD, but should also do the right thing in -portable on anything still using 32bit time_t (until the system time actually wraps, anyway). some early guidance deraadt@, ok djm@ Upstream-ID: c9f18613afb994a07e7622eb326f49de3d123b6c
2016-12-14upstream commitdjm@openbsd.org
log connections dropped in excess of MaxStartups at verbose LogLevel; bz#2613 based on diff from Tomas Kuthan; ok dtucker@ Upstream-ID: 703ae690dbf9b56620a6018f8a3b2389ce76d92b
2016-12-05upstream commitdtucker@openbsd.org
Unlink PidFile on SIGHUP and always recreate it when the new sshd starts. Regression tests (and possibly other things) depend on the pidfile being recreated after SIGHUP, and unlinking it means it won't contain a stale pid if sshd fails to restart. ok djm@ markus@ Upstream-ID: 132dd6dda0c77dd49d2f15b2573b5794f6160870
2016-11-30upstream commitdtucker@openbsd.org
On startup, check to see if sshd is already daemonized and if so, skip the call to daemon() and do not rewrite the PidFile. This means that when sshd re-execs itself on SIGHUP the process ID will no longer change. Should address bz#2641. ok djm@ markus@. Upstream-ID: 5ea0355580056fb3b25c1fd6364307d9638a37b9
2016-11-30factor out common PRNG reseed before privdropDamien Miller
Add a call to RAND_poll() to ensure than more than pid+time gets stirred into child processes states. Prompted by analysis from Jann Horn at Project Zero. ok dtucker@
2016-11-29upstream commitdtucker@openbsd.org
Factor out code to disconnect from controlling terminal into its own function. ok djm@ Upstream-ID: 39fd9e8ebd7222615a837312face5cc7ae962885
2016-09-29upstream commitdjm@openbsd.org
Remove support for pre-authentication compression. Doing compression early in the protocol probably seemed reasonable in the 1990s, but today it's clearly a bad idea in terms of both cryptography (cf. multiple compression oracle attacks in TLS) and attack surface. Moreover, to support it across privilege-separation zlib needed the assistance of a complex shared-memory manager that made the required attack surface considerably larger. Prompted by Guido Vranken pointing out a compiler-elided security check in the shared memory manager found by Stack (http://css.csail.mit.edu/stack/); ok deraadt@ markus@ NB. pre-auth authentication has been disabled by default in sshd for >10 years. Upstream-ID: 32af9771788d45a0779693b41d06ec199d849caf