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9 daysupstream: Add experimental support for hybrid post-quantum key exchangedjm@openbsd.org
ML-KEM768 with ECDH/X25519 from the Internet-draft: https://datatracker.ietf.org/doc/html/draft-kampanakis-curdle-ssh-pq-ke-03 This is based on previous patches from markus@ but adapted to use the final FIPS203 standard ML-KEM using a formally-verified implementation from libcrux. Note this key exchange method is still a draft and thus subject to change. It is therefore disabled by default; set MLKEM=yes to build it. We're making it available now to make it easy for other SSH implementations to test against it. ok markus@ deraadt@ OpenBSD-Commit-ID: 02a8730a570b63fa8acd9913ec66353735dea42c
2024-08-27upstream: As defined in the RFC, the SSH protocol has negotiablederaadt@openbsd.org
compression support (which is requested as the name "zlib"). Compression starts very early in the session. Relative early in OpenSSH lifetime, privsep was added to sshd, and this required a shared-memory hack so the two processes could see what was going on in the dataflow. This shared-memory hack was soon recognized as a tremendous complexity risk, because it put libz (which very much trusts it's memory) in a dangerous place, and a new option ("zlib@openssh.com") was added begins compression after authentication (aka delayed-compression). That change also permitted removal of the shared-memory hack. Despite removal from the server, the old "zlib" support remained in the client, to allow negotiation with non-OpenSSH daemons which lack the delayed-compression option. This commit deletes support for the older "zlib" option in the client. It reduces our featureset in a small way, and encourages other servers to move to a better design. The SSH protocol is different enough that compressed-key-material attacks like BEAST are unlikely, but who wants to take the chance? We encourage other ssh servers who care about optional compression support to add delayed-zlib support. (Some already do "zlib@openssh.com") ok djm markus OpenBSD-Commit-ID: 6df986f38e4ab389f795a6e39e7c6857a763ba72
2024-08-23upstream: sntrup761x25519-sha512 now has an IANA codepoint assigned, sodjm@openbsd.org
we can make the algorithm available without the @openssh.com suffix too. ok markus@ deraadt@ OpenBSD-Commit-ID: eeed8fcde688143a737729d3d56d20ab4353770f
2024-05-17upstream: Start the process of splitting sshd into separatedjm@openbsd.org
binaries. This step splits sshd into a listener and a session binary. More splits are planned. After this changes, the listener binary will validate the configuration, load the hostkeys, listen on port 22 and manage MaxStartups only. All session handling will be performed by a new sshd-session binary that the listener fork+execs. This reduces the listener process to the minimum necessary and sets us up for future work on the sshd-session binary. feedback/ok markus@ deraadt@ NB. if you're updating via source, please restart sshd after installing, otherwise you run the risk of locking yourself out. OpenBSD-Commit-ID: 43c04a1ab96cdbdeb53d2df0125a6d42c5f19934
2024-02-19upstream: whitespacedjm@openbsd.org
OpenBSD-Commit-ID: b24680bc755b621ea801ff8edf6f0f02b68edae1
2023-12-19upstream: add "ext-info-in-auth@openssh.com" extensiondjm@openbsd.org
This adds another transport protocol extension to allow a sshd to send SSH2_MSG_EXT_INFO during user authentication, after the server has learned the username that is being logged in to. This lets sshd to update the acceptable signature algoritms for public key authentication, and allows these to be varied via sshd_config(5) "Match" directives, which are evaluated after the server learns the username being authenticated. Full details in the PROTOCOL file OpenBSD-Commit-ID: 1de7da7f2b6c32a46043d75fcd49b0cbb7db7779
2023-12-19upstream: implement "strict key exchange" in ssh and sshddjm@openbsd.org
This adds a protocol extension to improve the integrity of the SSH transport protocol, particular in and around the initial key exchange (KEX) phase. Full details of the extension are in the PROTOCOL file. with markus@ OpenBSD-Commit-ID: 2a66ac962f0a630d7945fee54004ed9e9c439f14
2023-08-28upstream: Introduce a transport-level ping facilitydjm@openbsd.org
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". ok markus@ OpenBSD-Commit-ID: b6b3c4cb2084c62f85a8dc67cf74954015eb547f
2023-03-06upstream: Refactor creation of KEX proposal.dtucker@openbsd.org
This adds kex_proposal_populate_entries (and corresponding free) which populates the KEX proposal array with dynamically allocated strings. This replaces the previous mix of static and dynamic that has been the source of previous leaks and bugs. Remove unused compat functions. With & ok djm@. OpenBSD-Commit-ID: f2f99da4aae2233cb18bf9c749320c5e040a9c7b
2022-01-07upstream: Fix signature algorithm selection logic fordjm@openbsd.org
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 Mostly by Dmitry Belyavskiy with some tweaks by me. ok markus@ OpenBSD-Commit-ID: c17ba0c3236340d2c6a248158ebed042ac6a8029
2021-12-20upstream: client side of host-bound pubkey authenticationdjm@openbsd.org
Add kex->flags member to enable the publickey-hostbound-v00@openssh.com authentication method. Use the new hostbound method in client if the kex->flags flag was set, and include the inital KEX hostkey in the userauth request. Note: nothing in kex.c actually sets the new flag yet ok markus@ OpenBSD-Commit-ID: 5a6fce8c6c8a77a80ee1526dc467d91036a5910d
2021-12-20upstream: Record session ID, host key and sig at intital KEXdjm@openbsd.org
These will be used later for agent session ID / hostkey binding ok markus@ OpenBSD-Commit-ID: a9af29e33772b18e3e867c6fa8ab35e1694a81fe
2021-02-01upstream: more strictly enforce KEX state-machine by banning packetdjm@openbsd.org
types once they are received. Fixes memleak caused by duplicate SSH2_MSG_KEX_DH_GEX_REQUEST (spotted by portable OpenSSH kex_fuzz via oss-fuzz #30078). ok markus@ OpenBSD-Commit-ID: 87331c715c095b587d5c88724694cdeb701c9def
2021-01-27upstream: make ssh->kex->session_id a sshbuf instead of u_char*/size_tdjm@openbsd.org
and use that instead of global variables containing copies of it. feedback/ok markus@ OpenBSD-Commit-ID: a4b1b1ca4afd2e37cb9f64f737b30a6a7f96af68
2020-12-29upstream: Update/replace the experimental post-quantim hybrid keydjm@openbsd.org
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 the authors, sntrup4591761 was replaced almost two years ago by sntrup761. The sntrup761 implementaion, like sntrup4591761 before it, is public domain code extracted from the SUPERCOP cryptography benchmark suite (https://bench.cr.yp.to/supercop.html). Thanks for Daniel J Bernstein for guidance on algorithm selection. Patch from Tobias Heider; feedback & ok markus@ and myself (note this both the updated method and the one that it replaced are disabled by default) OpenBSD-Commit-ID: 2bf582b772d81ee24e911bb6f4b2aecfd39338ae
2020-10-07upstream: revert kex->flags cert hostkey downgrade back to a plaindjm@openbsd.org
key (commitid VtF8vozGOF8DMKVg). We now do this a simpler way that needs less plumbing. ok markus@ OpenBSD-Commit-ID: fb92d25b216bff8c136da818ac2221efaadf18ed
2020-10-03upstream: record when the host key checking code downgrades adjm@openbsd.org
certificate host key to a plain key. This occurs when the user connects to a host with a certificate host key but no corresponding CA key configured in known_hosts; feedback and ok markus@ OpenBSD-Commit-ID: 2ada81853ff9ee7824c62f440bcf4ad62030c901
2019-10-02remove duplicate #includesDamien Miller
Prompted by Jakub Jelen
2019-09-06upstream: fixes for !WITH_OPENSSL compilation; ok dtucker@djm@openbsd.org
OpenBSD-Commit-ID: 7fd68eaa9e0f7482b5d4c7e8d740aed4770a839f
2019-09-06upstream: remove leakmalloc reference; we used this early whendjm@openbsd.org
refactoring but not since OpenBSD-Commit-ID: bb28ebda8f7c490b87b37954044a6cdd43a7eb2c
2019-01-23upstream: pass most arguments to the KEX hash functions as sshbufdjm@openbsd.org
rather than pointer+length; ok markus@ OpenBSD-Commit-ID: ef0c89c52ccc89817a13a5205725148a28492bf7
2019-01-21upstream: rename kex->kem_client_pub -> kex->client_pub now thatdjm@openbsd.org
KEM has been renamed to kexgen from markus@ ok djm@ OpenBSD-Commit-ID: fac6da5dc63530ad0da537db022a9a4cfbe8bed8
2019-01-21upstream: pass values used in KEX hash computation as sshbufdjm@openbsd.org
rather than pointer+len suggested by me; implemented by markus@ ok me OpenBSD-Commit-ID: 994f33c464f4a9e0f1d21909fa3e379f5a0910f0
2019-01-21upstream: remove kex_derive_keys_bn wrapper; no unused since thedjm@openbsd.org
DH-like KEX methods have moved to KEM from markus@ ok djm@ OpenBSD-Commit-ID: bde9809103832f349545e4f5bb733d316db9a060
2019-01-21upstream: use KEM API for vanilla ECDHdjm@openbsd.org
from markus@ ok djm@ OpenBSD-Commit-ID: 6fbff96339a929835536b5730585d1d6057a352c
2019-01-21upstream: use KEM API for vanilla DH KEXdjm@openbsd.org
from markus@ ok djm@ OpenBSD-Commit-ID: af56466426b08a8be275412ae2743319e3d277c9
2019-01-21upstream: use KEM API for vanilla c25519 KEXdjm@openbsd.org
OpenBSD-Commit-ID: 38d937b85ff770886379dd66a8f32ab0c1c35c1f
2019-01-21upstream: Add support for a PQC KEX/KEM:djm@openbsd.org
sntrup4591761x25519-sha512@tinyssh.org using the Streamlined NTRU Prime 4591^761 implementation from SUPERCOP coupled with X25519 as a stop-loss. Not enabled by default. introduce KEM API; a simplified framework for DH-ish KEX methods. from markus@ feedback & ok djm@ OpenBSD-Commit-ID: d687f76cffd3561dd73eb302d17a1c3bf321d1a7
2019-01-21upstream: factor out kex_verify_hostkey() - again, duplicateddjm@openbsd.org
almost exactly across client and server for several KEX methods. from markus@ ok djm@ OpenBSD-Commit-ID: 4e4a16d949dadde002a0aacf6d280a684e20829c
2019-01-21upstream: factor out kex_load_hostkey() - this is duplicated indjm@openbsd.org
both the client and server implementations for most KEX methods. from markus@ ok djm@ OpenBSD-Commit-ID: 8232fa7c21fbfbcaf838313b0c166dc6c8762f3c
2019-01-21upstream: factor out kex_dh_compute_key() - it's shared betweendjm@openbsd.org
plain DH KEX and DH GEX in both the client and server implementations from markus@ ok djm@ OpenBSD-Commit-ID: 12186e18791fffcd4642c82e7e0cfdd7ea37e2ec
2019-01-21upstream: factor out DH keygen; it's identical between the clientdjm@openbsd.org
and the server from markus@ ok djm@ OpenBSD-Commit-ID: 2be57f6a0d44f1ab2c8de2b1b5d6f530c387fae9
2019-01-20upstream: remove last references to active_statedjm@openbsd.org
with & ok markus@ OpenBSD-Commit-ID: 78619a50ea7e4ca2f3b54d4658b3227277490ba2
2018-12-27upstream: move client/server SSH-* banners to buffers underdjm@openbsd.org
ssh->kex and factor out the banner exchange. This eliminates some common code from the client and server. Also be more strict about handling \r characters - these should only be accepted immediately before \n (pointed out by Jann Horn). Inspired by a patch from Markus Schmidt. (lots of) feedback and ok markus@ OpenBSD-Commit-ID: 1cc7885487a6754f63641d7d3279b0941890275b
2018-12-27upstream: only consider the ext-info-c extension during the initialdjm@openbsd.org
KEX. It shouldn't be sent in subsequent ones, but if it is present we should ignore it. This prevents sshd from sending a SSH_MSG_EXT_INFO for REKEX for buggy these clients. Reported by Jakub Jelen via bz2929; ok dtucker@ OpenBSD-Commit-ID: 91564118547f7807030ec537480303e2371902f9
2018-07-13repair !WITH_OPENSSL buildDamien Miller
2018-07-12upstream: remove legacy key emulation layer; ok djm@markus@openbsd.org
OpenBSD-Commit-ID: 2b1f9619259e222bbd4fe9a8d3a0973eafb9dd8d
2018-07-11upstream: re-remove some pre-auth compression bitssf@openbsd.org
This time, make sure to not remove things that are necessary for pre-auth compression on the client. Add a comment that pre-auth compression is still supported in the client. ok markus@ OpenBSD-Commit-ID: 282c6fec7201f18a5c333bbb68d9339734d2f784
2018-07-10upstream: remove legacy buffer API emulation layer; ok djm@markus@openbsd.org
OpenBSD-Commit-ID: 2dd5dc17cbc23195be4299fa93be2707a0e08ad9
2018-07-10upstream: Revert previous two commitssf@openbsd.org
It turns out we still support pre-auth compression on the client. Therefore revert the previous two commits: date: 2018/07/06 09:06:14; author: sf; commitid: yZVYKIRtUZWD9CmE; Rename COMP_DELAYED to COMP_ZLIB Only delayed compression is supported nowadays. ok markus@ date: 2018/07/06 09:05:01; author: sf; commitid: rEGuT5UgI9f6kddP; Remove leftovers from pre-authentication compression Support for this has been removed in 2016. COMP_DELAYED will be renamed in a later commit. ok markus@ OpenBSD-Commit-ID: cdfef526357e4e1483c86cf599491b2dafb77772
2018-07-10upstream: Rename COMP_DELAYED to COMP_ZLIBsf@openbsd.org
Only delayed compression is supported nowadays. ok markus@ OpenBSD-Commit-ID: 5b1dbaf3d9a4085aaa10fec0b7a4364396561821
2018-07-10upstream: Remove leftovers from pre-authentication compressionsf@openbsd.org
Support for this has been removed in 2016. COMP_DELAYED will be renamed in a later commit. ok markus@ OpenBSD-Commit-ID: 6a99616c832627157113fcb0cf5a752daf2e6b58
2018-07-04upstream: repair PubkeyAcceptedKeyTypes (and friends) after RSAdjm@openbsd.org
signature work - returns ability to add/remove/specify algorithms by wildcard. Algorithm lists are now fully expanded when the server/client configs are finalised, so errors are reported early and the config dumps (e.g. "ssh -G ...") now list the actual algorithms selected. Clarify that, while wildcards are accepted in algorithm lists, they aren't full pattern-lists that support negation. (lots of) feedback, ok markus@ OpenBSD-Commit-ID: a8894c5c81f399a002f02ff4fe6b4fa46b1f3207
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
2017-05-31upstream commitmarkus@openbsd.org
protocol handlers all get struct ssh passed; ok djm@ Upstream-ID: 0ca9ea2a5d01a6d2ded94c5024456a930c5bfb5d
2017-05-08upstream commitnaddy@openbsd.org
remove miscellaneous SSH1 leftovers; ok markus@ Upstream-ID: af23696022ae4d45a1abc2fb8b490d8d9dd63b7c
2016-09-29upstream commitdjm@openbsd.org
put back some pre-auth zlib bits that I shouldn't have removed - they are still used by the client. Spotted by naddy@ Upstream-ID: 80919468056031037d56a1f5b261c164a6f90dc2
2016-09-29upstream commitdjm@openbsd.org
restore pre-auth compression support in the client -- the previous commit was intended to remove it from the server only. remove a few server-side pre-auth compression bits that escaped adjust wording of Compression directive in sshd_config(5) pointed out by naddy@ ok markus@ Upstream-ID: d23696ed72a228dacd4839dd9f2dec424ba2016b
2016-09-24upstream commitdjm@openbsd.org
missing bit from previous commit Upstream-ID: 438d5ed6338b28b46e822eb13eee448aca31df37
2016-05-02upstream commitdjm@openbsd.org
add support for additional fixed DH groups from draft-ietf-curdle-ssh-kex-sha2-03 diffie-hellman-group14-sha256 (2K group) diffie-hellman-group16-sha512 (4K group) diffie-hellman-group18-sha512 (8K group) based on patch from Mark D. Baushke and Darren Tucker ok markus@ Upstream-ID: ac00406ada4f0dfec41585ca0839f039545bc46f
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-11 03:07:58 +0000