[Bug 2319] [PATCH REVIEW] U2F authentication
https://bugzilla.mindrot.org/show_bug.cgi?id=2319 --- Comment #6 from Michael Stapelberg michael+mind...@stapelberg.de --- (In reply to Damien Miller from comment #5) (In reply to Michael Stapelberg from comment #3) (In reply to Damien Miller from comment #2) I think it is best that you start with a description of the u2f authentication method protocol - it's much better to review that the protocol is sound before looking at the implementation. Could you write this up? From that comment it sounds like there is some misunderstanding here :). U2F stands for Universal Second Factor, see also http://en.wikipedia.org/wiki/Universal_2nd_Factor You can find the protocol specification on http://fidoalliance.org/specifications/download/ I’ve done a presentation at our local computer club, you can find the slides here: https://www.noname-ev.de/w/File:C14h-u2f-how-security-keys-work.pdf — they contain a pretty high-level and easy to understand description of U2F. Is that what you were looking for? If not, let me know :). No, I'm looking for a description of what goes on the wire for SSH. Like what RFC4252 does for the existing SSH authentication methods. Ah, I see. Here goes: When the client starts the u2f authentication, it sends: byte SSH_MSG_USERAUTH_REQUEST stringuser name in ISO-10646 UTF-8 encoding [RFC3629] stringservice name in US-ASCII stringmethod name in US-ASCII uint32U2F mode (authentication or registration) 1) In case the client requests registration, the server replies with: byte SSH2_MSG_USERAUTH_INFO_REQUEST stringRegisterRequest Where RegisterRequest is specified in http://fidoalliance.org/specs/fido-u2f-v1.0-ps-20141009/fido-u2f-javascript-api-ps-20141009.html#dictionary-registerrequest-members After sending 'RegisterRequest' to the U2F security key, the client sends back the security key’s response (see http://fidoalliance.org/specs/fido-u2f-v1.0-ps-20141009/fido-u2f-javascript-api-ps-20141009.html#dictionary-registerresponse-members): byte SSH2_MSG_USERAUTH_INFO_RESPONSE stringRegisterResponse Once the server verified the 'RegisterResponse' indeed signed the original challenge, it extracts the user’s U2F public key and sends back a ssh-u2f key line which the user should add to her authorized_keys file: byte SSH2_MSG_USERAUTH_INFO_REQUEST stringauthorizedKey 2) In case the client requests authentication, the server replies with: byte SSH2_MSG_USERAUTH_INFO_REQUEST stringSignRequest After sending 'SignRequest' (see http://fidoalliance.org/specs/fido-u2f-v1.0-ps-20141009/fido-u2f-javascript-api-ps-20141009.html#dictionary-signrequest-members) to the U2F security key, the client sends back the security key’s response: byte SSH2_MSG_USERAUTH_INFO_RESPONSE stringSignResponse The authentication is successful if the server successfully verifies that the signature on the 'SignResponse' was created with the formerly registered public key. As you can see, the protocol on the wire is fairly simple — I just follow the JavaScript API because that is what libu2f-host expects. Hope that helps, let me know if you have more questions. -- You are receiving this mail because: You are watching someone on the CC list of the bug. You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2332] Show more secure fingerprints than MD5 (e.g. SHA256) in ssh and ssh-keygen
https://bugzilla.mindrot.org/show_bug.cgi?id=2332 Damien Miller d...@mindrot.org changed: What|Removed |Added CC||d...@mindrot.org --- Comment #4 from Damien Miller d...@mindrot.org --- (In reply to Petr Lautrbach from comment #3) But there seems to be a bug that you can't overwrite FingerprintHash option on the command line when it's set in a config file. Can you give me a recipe to reproduce? -- You are receiving this mail because: You are watching someone on the CC list of the bug. You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2332] Show more secure fingerprints than MD5 (e.g. SHA256) in ssh and ssh-keygen
https://bugzilla.mindrot.org/show_bug.cgi?id=2332 Petr Lautrbach plaut...@redhat.com changed: What|Removed |Added CC||plaut...@redhat.com --- Comment #1 from Petr Lautrbach plaut...@redhat.com --- It seems to be already changed in the development tree, see https://anongit.mindrot.org/openssh.git/commit/?id=56d1c83cdd1ac76f1c6bd41e01e80dad834f3994 -- You are receiving this mail because: You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2334] New: Warn when weak Ciphers are used
https://bugzilla.mindrot.org/show_bug.cgi?id=2334 Bug ID: 2334 Summary: Warn when weak Ciphers are used Product: Portable OpenSSH Version: 6.7p1 Hardware: Other OS: Linux Status: NEW Severity: enhancement Priority: P5 Component: ssh Assignee: unassigned-b...@mindrot.org Reporter: thorsten.s...@email.de Warn the user when the SSH client or server are using weak ciphers. This can be done by default, when using -v or on a specific test-security parameter. Client and Server settings should be tested. According to https://stribika.github.io/2015/01/04/secure-secure-shell.html Many ciphers (but not all) are either weak or broken. By having an automatic test in the tools we can improve the settings of the currently used servers and clients. That would improve the average security level in a simple anbd efficient way. -- You are receiving this mail because: You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2333] forbid old Ciphers, KexAlgorithms and MACs by default
https://bugzilla.mindrot.org/show_bug.cgi?id=2333 --- Comment #3 from kolafl...@kolahilft.de --- I don't know any halfway recent SSH implementation that shouldn't work without these. Nevertheless: What about a user-warning in interactive mode? -- You are receiving this mail because: You are watching someone on the CC list of the bug. You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2332] Show more secure fingerprints than MD5 (e.g. SHA256) in ssh and ssh-keygen
https://bugzilla.mindrot.org/show_bug.cgi?id=2332 --- Comment #3 from Petr Lautrbach plaut...@redhat.com --- You can put FingerprintHash=md5 into your ssh config files (/etc/ssh/ssh_config, ~/.ssh/config) or use '-o FingerprintHash=md5' directly on the command line. $ ssh localhost The authenticity of host 'localhost (127.0.0.1)' can't be established. ECDSA key fingerprint is SHA256:WvwqGxIhzB8L7L3/V9v9cI4IZ+IxTtAGo2FXFRfpPSQ. $ ssh -o FingerprintHash=md5 localhost The authenticity of host 'localhost (127.0.0.1)' can't be established. ECDSA key fingerprint is MD5:da:24:43:0b:2e:c1:3f:a1:84:13:92:01:52:b4:84:ff. ... $ ssh -o FingerprintHash=sha512 localhost The authenticity of host 'localhost (127.0.0.1)' can't be established. ECDSA key fingerprint is SHA512:lbvPnoYkOXD0yOv7C1iLFjrlPz0sg5ImLzT7ffZTte4iJ7MmZtHjBTRm9EimMAYKNGgB5XEHDs8gnCPnJCf5dQ. But there seems to be a bug that you can't overwrite FingerprintHash option on the command line when it's set in a config file. -- You are receiving this mail because: You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2332] Show more secure fingerprints than MD5 (e.g. SHA256) in ssh and ssh-keygen
https://bugzilla.mindrot.org/show_bug.cgi?id=2332 --- Comment #2 from kolafl...@kolahilft.de --- Just tested the current version from Git. SHA256 is working great! Gives me the SHA256 or MD5 fingerprint: ssh-keygen -lv -E SHA256 -f id_rsa.pub ssh-keygen -lv -E MD5 -f id_rsa.pub But: SSH client also needs an option to show MD5 (like ssh-keygen). Why not also offer SHA512 for really paranoid people? -- You are receiving this mail because: You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2306] ssh-add 6.7 inserts RSA keys into the ssh-agent as rsa w/o comment instead of filenames
https://bugzilla.mindrot.org/show_bug.cgi?id=2306 Damien Miller d...@mindrot.org changed: What|Removed |Added Resolution|--- |FIXED Status|ASSIGNED|RESOLVED --- Comment #1 from Damien Miller d...@mindrot.org --- Fixed: commit 1195f4cb07ef4b0405c839293c38600b3e9bdb46 Author: d...@openbsd.org d...@openbsd.org Date: Thu Jan 8 10:14:08 2015 + upstream commit deprecate key_load_private_pem() and sshkey_load_private_pem() interfaces. Refactor the generic key loading API to not require pathnames to be specified (they weren't really used). Fixes a few other things en passant: Makes ed25519 keys work for hostbased authentication (ssh-keysign previously used the PEM-only routines). Fixes key comment regression bz#2306: key pathnames were being lost as comment fields. ok markus@ -- You are receiving this mail because: You are watching someone on the CC list of the bug. You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2266] Bugs intended to be fixed in 6.8
https://bugzilla.mindrot.org/show_bug.cgi?id=2266 Bug 2266 depends on bug 2306, which changed state. Bug 2306 Summary: ssh-add 6.7 inserts RSA keys into the ssh-agent as rsa w/o comment instead of filenames https://bugzilla.mindrot.org/show_bug.cgi?id=2306 What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED -- You are receiving this mail because: You are watching the assignee of the bug. You are watching the reporter of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2332] Show more secure fingerprints than MD5 (e.g. SHA256) in ssh and ssh-keygen
https://bugzilla.mindrot.org/show_bug.cgi?id=2332 --- Comment #6 from Petr Lautrbach plaut...@redhat.com --- works for me with this patch: --- a/readconf.c +++ b/readconf.c @@ -1464,6 +1464,7 @@ parse_int: goto parse_string; case oFingerprintHash: + intptr = options-fingerprint_hash; arg = strdelim(s); if (!arg || *arg == '\0') fatal(%.200s line %d: Missing argument., @@ -1471,8 +1472,8 @@ parse_int: if ((value = ssh_digest_alg_by_name(arg)) == -1) fatal(%.200s line %d: Invalid hash algorithm \%s\., filename, linenum, arg); - if (*activep) - options-fingerprint_hash = value; + if (*activep *intptr == -1) + *intptr = value; break; case oDeprecated: -- You are receiving this mail because: You are watching the assignee of the bug. You are watching someone on the CC list of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 2332] Show more secure fingerprints than MD5 (e.g. SHA256) in ssh and ssh-keygen
https://bugzilla.mindrot.org/show_bug.cgi?id=2332 Damien Miller d...@mindrot.org changed: What|Removed |Added Status|NEW |RESOLVED Resolution|--- |FIXED --- Comment #7 from Damien Miller d...@mindrot.org --- applied - thanks. I don't think there is anything left unfinished in this bug then :) -- You are receiving this mail because: You are watching the assignee of the bug. You are watching someone on the CC list of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 1768] scp: wrong error message when destination directory ends with a slash and is missing
https://bugzilla.mindrot.org/show_bug.cgi?id=1768 Jakub Jelen jje...@redhat.com changed: What|Removed |Added CC||jje...@redhat.com --- Comment #2 from Jakub Jelen jje...@redhat.com --- Created attachment 2523 -- https://bugzilla.mindrot.org/attachment.cgi?id=2523action=edit patch to improve error message Hi, I ran into this problem in RHBZ#1142223 [1] and tried to solve it. After some time of digging in the source code I came up with solution which I introduce here as a attachment. This added condition covers only this one problematic case and according to regression test cases published in portable tarbal, shouldn't bring here any regression. Also I managed to write test case covering this problem. This file will be attached as the second file. Also I would like to say that the previous patch doesn't work, because it will break recursive scp, for example: scp -r dir/ host:new_dir/ which is completely valid even if the new_dir doesn't exist. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1142223 -- You are receiving this mail because: You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
[Bug 1768] scp: wrong error message when destination directory ends with a slash and is missing
https://bugzilla.mindrot.org/show_bug.cgi?id=1768 --- Comment #3 from Jakub Jelen jje...@redhat.com --- Created attachment 2524 -- https://bugzilla.mindrot.org/attachment.cgi?id=2524action=edit patch to verify this problem in regress test suite -- You are receiving this mail because: You are watching the assignee of the bug. ___ openssh-bugs mailing list openssh-bugs@mindrot.org https://lists.mindrot.org/mailman/listinfo/openssh-bugs
