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2022-03-13Merge branch 'fs/gpgsm-update'Libravatar Junio C Hamano1-1/+8
Newer version of GPGSM changed its output in a backward incompatible way to break our code that parses its output. It also added more processes our tests need to kill when cleaning up. Adjustments have been made to accommodate these changes. * fs/gpgsm-update: t/lib-gpg: kill all gpg components, not just gpg-agent t/lib-gpg: reload gpg components after updating trustlist gpg-interface/gpgsm: fix for v2.3
2022-03-04gpg-interface/gpgsm: fix for v2.3Libravatar Fabian Stelzer1-1/+8
Checking if signing was successful will now accept '[GNUPG]: SIG_CREATED' on the beginning of the first or any subsequent line. Not just explictly the second one anymore. Gpgsm v2.3 changed its output when listing keys from `fingerprint` to `sha1/2 fpr`. This leads to the gpgsm tests silently not being executed because of a failed prerequisite. Switch to gpg's `--with-colons` output format when evaluating test prerequisites to make parsing more robust. This also allows us to combine the existing grep/cut/tr/echo pipe for writing the trustlist.txt into a single awk expression. Adjust error message checking in test for v2.3 specific output changes. Helped-By: Junio C Hamano <gitster@pobox.com> Helped-By: Todd Zullinger <tmz@pobox.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-25Merge branch 'ja/i18n-common-messages'Libravatar Junio C Hamano1-3/+3
Unify more messages to help l10n. * ja/i18n-common-messages: i18n: fix some misformated placeholders in command synopsis i18n: remove from i18n strings that do not hold translatable parts i18n: factorize "invalid value" messages i18n: factorize more 'incompatible options' messages
2022-02-04i18n: factorize "invalid value" messagesLibravatar Jean-Noël Avila1-3/+3
Use the same message when an invalid value is passed to a command line option or a configuration variable. Signed-off-by: Jean-Noël Avila <jn.avila@free.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-01-07gpg-interface: trim CR from ssh-keygenLibravatar Fabian Stelzer1-10/+24
We need to trim \r from the output of 'ssh-keygen -Y find-principals' on Windows, or we end up calling 'ssh-keygen -Y verify' with a bogus signer identity. ssh-keygen.c:2841 contains a call to puts(3), which confirms this hypothesis. Signature verification passes with the fix. Helped-by: Pedro Martelletto <pedro@yubico.com> Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-21Merge branch 'fs/ssh-signing-other-keytypes'Libravatar Junio C Hamano1-7/+29
The cryptographic signing using ssh keys can specify literal keys for keytypes whose name do not begin with the "ssh-" prefix by using the "key::" prefix mechanism (e.g. "key::ecdsa-sha2-nistp256"). * fs/ssh-signing-other-keytypes: ssh signing: make sign/amend test more resilient ssh signing: support non ssh-* keytypes
2021-12-09ssh signing: make verify-commit consider key lifetimeLibravatar Fabian Stelzer1-0/+53
If valid-before/after dates are configured for this signatures key in the allowedSigners file then the verification should check if the key was valid at the time the commit was made. This allows for graceful key rollover and revoking keys without invalidating all previous commits. This feature needs openssh > 8.8. Older ssh-keygen versions will simply ignore this flag and use the current time. Strictly speaking this feature is available in 8.7, but since 8.7 has a bug that makes it unusable in another needed call we require 8.8. Timestamp information is present on most invocations of check_signature. However signer ident is not. We will need the signer email / name to be able to implement "Trust on first use" functionality later. Since the payload contains all necessary information we can parse it from there. The caller only needs to provide us some info about the payload by setting payload_type in the signature_check struct. - Add payload_type field & enum and payload_timestamp to struct signature_check - Populate the timestamp when not already set if we know about the payload type - Pass -Overify-time={payload_timestamp} in the users timezone to all ssh-keygen verification calls - Set the payload type when verifying commits - Add tests for expired, not yet valid and keys having a commit date outside of key validity as well as within Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-09ssh signing: use sigc struct to pass payloadLibravatar Fabian Stelzer1-20/+17
To be able to extend the payload metadata with things like its creation timestamp or the creators ident we remove the payload parameters to check_signature() and use the already existing sigc->payload field instead, only adding the length field to the struct. This also allows us to get rid of the xmemdupz() calls in the verify functions. Since sigc is now used to input data as well as output the result move it to the front of the function list. - Add payload_length to struct signature_check - Populate sigc.payload/payload_len on all call sites - Remove payload parameters to check_signature() - Remove payload parameters to internal verify_* functions and use sigc instead - Remove xmemdupz() used for verbose output since payload is now already populated. Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-19ssh signing: support non ssh-* keytypesLibravatar Fabian Stelzer1-7/+29
The user.signingKey config for ssh signing supports either a path to a file containing the key or for the sake of convenience a literal string with the ssh public key. To differentiate between those two cases we check if the first few characters contain "ssh-" which is unlikely to be the start of a path. ssh supports other key types which are not prefixed with "ssh-" and will currently be treated as a file path and therefore fail to load. To remedy this we move the prefix check into its own function and introduce the prefix `key::` for literal ssh keys. This way we don't need to add new key types when they become available. The existing `ssh-` prefix is retained for compatibility with current user configs but removed from the official documentation to discourage its use. Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-03Merge branch 'jx/message-fixes'Libravatar Junio C Hamano1-1/+1
Fixes to recently added messages. * jx/message-fixes: i18n: fix typos found during l10n for git 2.34.0
2021-11-01gpg-interface: avoid buffer overrun in parse_ssh_output()Libravatar René Scharfe1-2/+2
If the string "key" we found in the output of ssh-keygen happens to be located at the very end of the line, then going four characters further leaves us beyond the end of the string. Explicitly search for the space after "key" to handle a missing one gracefully. Signed-off-by: René Scharfe <l.s.r@web.de> Acked-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-01gpg-interface: handle missing " with " gracefully in parse_ssh_output()Libravatar René Scharfe1-4/+6
If the output of ssh-keygen starts with "Good \"git\" signature for ", but is not followed by " with " for some reason, then parse_ssh_output() uses -1 as the len parameter of xmemdupz(), which in turn will end the program. Reject the signature and carry on instead in that case. Signed-off-by: René Scharfe <l.s.r@web.de> Acked-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-31i18n: fix typos found during l10n for git 2.34.0Libravatar Jiang Xin1-1/+1
Emir and Jean-Noël reported typos in some i18n messages when preparing l10n for git 2.34.0. * Fix unstable spelling of config variable "gpg.ssh.defaultKeyCommand" which was introduced in commit fd9e226776 (ssh signing: retrieve a default key from ssh-agent, 2021-09-10). * Add missing space between "with" and "--python" which was introduced in commit bd0708c7eb (ref-filter: add %(raw) atom, 2021-07-26). * Fix unmatched single quote in 'builtin/index-pack.c' which was introduced in commit 8737dab346 (index-pack: refactor renaming in final(), 2021-09-09) [1] https://github.com/git-l10n/git-po/pull/567 Reported-by: Emir Sarı <bitigchi@me.com> Reported-by: Jean-Noël Avila <jn.avila@free.fr> Signed-off-by: Jiang Xin <worldhello.net@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-18gpg-interface: fix leak of strbufs in get_ssh_key_fingerprint()Libravatar Jeff King1-1/+5
We read stdout from gpg into a strbuf, then split it into a list of strbufs, pull out one element, and return it. But we don't free either the original stdout buffer, nor the list returned from strbuf_split(). This patch fixes both. Note that we have to detach the returned string from its strbuf before calling strbuf_list_free(), as that would otherwise throw it away. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-18gpg-interface: fix leak of "line" in parse_ssh_output()Libravatar Jeff King1-2/+6
We xmemdupz() this buffer, but never free it. Let's do so. We'll use a cleanup label, since there are multiple exits from the function. Note that it was also declared a "const char *". We could switch that to "char *" to indicate that it's allocated, but that make it awkward to use with skip_prefix(). So instead, we'll introduce an extra non-const pointer. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10ssh signing: verify signatures using ssh-keygenLibravatar Fabian Stelzer1-2/+213
To verify a ssh signature we first call ssh-keygen -Y find-principal to look up the signing principal by their public key from the allowedSignersFile. If the key is found then we do a verify. Otherwise we only validate the signature but can not verify the signers identity. Verification uses the gpg.ssh.allowedSignersFile (see ssh-keygen(1) "ALLOWED SIGNERS") which contains valid public keys and a principal (usually user@domain). Depending on the environment this file can be managed by the individual developer or for example generated by the central repository server from known ssh keys with push access. This file is usually stored outside the repository, but if the repository only allows signed commits/pushes, the user might choose to store it in the repository. To revoke a key put the public key without the principal prefix into gpg.ssh.revocationKeyring or generate a KRL (see ssh-keygen(1) "KEY REVOCATION LISTS"). The same considerations about who to trust for verification as with the allowedSignersFile apply. Using SSH CA Keys with these files is also possible. Add "cert-authority" as key option between the principal and the key to mark it as a CA and all keys signed by it as valid for this CA. See "CERTIFICATES" in ssh-keygen(1). Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10ssh signing: provide a textual signing_key_idLibravatar Fabian Stelzer1-0/+56
For ssh the user.signingkey can be a filename/path or even a literal ssh pubkey. In push certs and textual output we prefer the ssh fingerprint instead. Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10ssh signing: retrieve a default key from ssh-agentLibravatar Fabian Stelzer1-2/+68
If user.signingkey is not set and a ssh signature is requested we call gpg.ssh.defaultKeyCommand (typically "ssh-add -L") and use the first key we get Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10ssh signing: add ssh key format and signing codeLibravatar Fabian Stelzer1-8/+130
Implements the actual sign_buffer_ssh operation and move some shared cleanup code into a strbuf function Set gpg.format = ssh and user.signingkey to either a ssh public key string (like from an authorized_keys file), or a ssh key file. If the key file or the config value itself contains only a public key then the private key needs to be available via ssh-agent. gpg.ssh.program can be set to an alternative location of ssh-keygen. A somewhat recent openssh version (8.2p1+) of ssh-keygen is needed for this feature. Since only ssh-keygen is needed it can this way be installed seperately without upgrading your system openssh packages. Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10ssh signing: preliminary refactoring and clean-upLibravatar Fabian Stelzer1-40/+64
Openssh v8.2p1 added some new options to ssh-keygen for signature creation and verification. These allow us to use ssh keys for git signatures easily. In our corporate environment we use PIV x509 Certs on Yubikeys for email signing/encryption and ssh keys which I think is quite common (at least for the email part). This way we can establish the correct trust for the SSH Keys without setting up a separate GPG Infrastructure (which is still quite painful for users) or implementing x509 signing support for git (which lacks good forwarding mechanisms). Using ssh agent forwarding makes this feature easily usable in todays development environments where code is often checked out in remote VMs / containers. In such a setup the keyring & revocationKeyring can be centrally generated from the x509 CA information and distributed to the users. To be able to implement new signing formats this commit: - makes the sigc structure more generic by renaming "gpg_output" to "output" - introduces function pointers in the gpg_format structure to call format specific signing and verification functions - moves format detection from verify_signed_buffer into the check_signature api function and calls the format specific verify - renames and wraps sign_buffer to handle format specific signing logic as well Signed-off-by: Fabian Stelzer <fs@gigacodes.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-10gpg-interface: remove other signature headers before verifyingLibravatar brian m. carlson1-0/+2
When we have a multiply signed commit, we need to remove the signature in the header before verifying the object, since the trailing signature will not be over both pieces of data. Do so, and verify that we validate the signature appropriately. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-10gpg-interface: improve interface for parsing tagsLibravatar brian m. carlson1-1/+12
We have a function which parses a buffer with a signature at the end, parse_signature, and this function is used for signed tags. However, we'll need to store values for multiple algorithms, and we'll do this by using a header for the non-default algorithm. Adjust the parse_signature interface to store the parsed data in two strbufs and turn the existing function into parse_signed_buffer. The latter is still used in places where we know we always have a signed buffer, such as push certs. Adjust all the callers to deal with this new interface. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-28strvec: fix indentation in renamed callsLibravatar Jeff King1-7/+7
Code which split an argv_array call across multiple lines, like: argv_array_pushl(&args, "one argument", "another argument", "and more", NULL); was recently mechanically renamed to use strvec, which results in mis-matched indentation like: strvec_pushl(&args, "one argument", "another argument", "and more", NULL); Let's fix these up to align the arguments with the opening paren. I did this manually by sifting through the results of: git jump grep 'strvec_.*,$' and liberally applying my editor's auto-format. Most of the changes are of the form shown above, though I also normalized a few that had originally used a single-tab indentation (rather than our usual style of aligning with the open paren). I also rewrapped a couple of obvious cases (e.g., where previously too-long lines became short enough to fit on one), but I wasn't aggressive about it. In cases broken to three or more lines, the grouping of arguments is sometimes meaningful, and it wasn't worth my time or reviewer time to ponder each case individually. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-28strvec: convert more callers away from argv_array nameLibravatar Jeff King1-4/+4
We eventually want to drop the argv_array name and just use strvec consistently. There's no particular reason we have to do it all at once, or care about interactions between converted and unconverted bits. Because of our preprocessor compat layer, the names are interchangeable to the compiler (so even a definition and declaration using different names is OK). This patch converts remaining files from the first half of the alphabet, to keep the diff to a manageable size. The conversion was done purely mechanically with: git ls-files '*.c' '*.h' | xargs perl -i -pe ' s/ARGV_ARRAY/STRVEC/g; s/argv_array/strvec/g; ' and then selectively staging files with "git add '[abcdefghjkl]*'". We'll deal with any indentation/style fallouts separately. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-15gpg-interface: prefer check_signature() for GPG verificationLibravatar Hans Jerry Illikainen1-48/+49
This commit refactors the use of verify_signed_buffer() outside of gpg-interface.c to use check_signature() instead. It also turns verify_signed_buffer() into a file-local function since it's now only invoked internally by check_signature(). There were previously two globally scoped functions used in different parts of Git to perform GPG signature verification: verify_signed_buffer() and check_signature(). Now only check_signature() is used. The verify_signed_buffer() function doesn't guard against duplicate signatures as described by Michał Górny [1]. Instead it only ensures a non-erroneous exit code from GPG and the presence of at least one GOODSIG status field. This stands in contrast with check_signature() that returns an error if more than one signature is encountered. The lower degree of verification makes the use of verify_signed_buffer() problematic if callers don't parse and validate the various parts of the GPG status message themselves. And processing these messages seems like a task that should be reserved to gpg-interface.c with the function check_signature(). Furthermore, the use of verify_signed_buffer() makes it difficult to introduce new functionality that relies on the content of the GPG status lines. Now all operations that does signature verification share a single entry point to gpg-interface.c. This makes it easier to propagate changed or additional functionality in GPG signature verification to all parts of Git, without having odd edge-cases that don't perform the same degree of verification. [1] https://dev.gentoo.org/~mgorny/articles/attack-on-git-signature-verification.html Signed-off-by: Hans Jerry Illikainen <hji@dyntopia.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-05Merge branch 'hi/gpg-use-check-signature'Libravatar Junio C Hamano1-49/+48
"git merge signed-tag" while lacking the public key started to say "No signature", which was utterly wrong. This regression has been reverted. * hi/gpg-use-check-signature: Revert "gpg-interface: prefer check_signature() for GPG verification"
2020-02-28Revert "gpg-interface: prefer check_signature() for GPG verification"Libravatar Junio C Hamano1-49/+48
This reverts commit 72b006f4bfd30b7c5037c163efaf279ab65bea9c, which breaks the end-user experience when merging a signed tag without having the public key. We should report "can't check because we have no public key", but the code with this change claimed that there was no signature.
2020-01-30Merge branch 'hi/gpg-mintrustlevel'Libravatar Junio C Hamano1-12/+79
gpg.minTrustLevel configuration variable has been introduced to tell various signature verification codepaths the required minimum trust level. * hi/gpg-mintrustlevel: gpg-interface: add minTrustLevel as a configuration option
2020-01-15gpg-interface: add minTrustLevel as a configuration optionLibravatar Hans Jerry Illikainen1-12/+79
Previously, signature verification for merge and pull operations checked if the key had a trust-level of either TRUST_NEVER or TRUST_UNDEFINED in verify_merge_signature(). If that was the case, the process die()d. The other code paths that did signature verification relied entirely on the return code from check_commit_signature(). And signatures made with a good key, irregardless of its trust level, was considered valid by check_commit_signature(). This difference in behavior might induce users to erroneously assume that the trust level of a key in their keyring is always considered by Git, even for operations where it is not (e.g. during a verify-commit or verify-tag). The way it worked was by gpg-interface.c storing the result from the key/signature status *and* the lowest-two trust levels in the `result` member of the signature_check structure (the last of these status lines that were encountered got written to `result`). These are documented in GPG under the subsection `General status codes` and `Key related`, respectively [1]. The GPG documentation says the following on the TRUST_ status codes [1]: """ These are several similar status codes: - TRUST_UNDEFINED <error_token> - TRUST_NEVER <error_token> - TRUST_MARGINAL [0 [<validation_model>]] - TRUST_FULLY [0 [<validation_model>]] - TRUST_ULTIMATE [0 [<validation_model>]] For good signatures one of these status lines are emitted to indicate the validity of the key used to create the signature. The error token values are currently only emitted by gpgsm. """ My interpretation is that the trust level is conceptionally different from the validity of the key and/or signature. That seems to also have been the assumption of the old code in check_signature() where a result of 'G' (as in GOODSIG) and 'U' (as in TRUST_NEVER or TRUST_UNDEFINED) were both considered a success. The two cases where a result of 'U' had special meaning were in verify_merge_signature() (where this caused git to die()) and in format_commit_one() (where it affected the output of the %G? format specifier). I think it makes sense to refactor the processing of TRUST_ status lines such that users can configure a minimum trust level that is enforced globally, rather than have individual parts of git (e.g. merge) do it themselves (except for a grace period with backward compatibility). I also think it makes sense to not store the trust level in the same struct member as the key/signature status. While the presence of a TRUST_ status code does imply that the signature is good (see the first paragraph in the included snippet above), as far as I can tell, the order of the status lines from GPG isn't well-defined; thus it would seem plausible that the trust level could be overwritten with the key/signature status if they were stored in the same member of the signature_check structure. This patch introduces a new configuration option: gpg.minTrustLevel. It consolidates trust-level verification to gpg-interface.c and adds a new `trust_level` member to the signature_check structure. Backward-compatibility is maintained by introducing a special case in verify_merge_signature() such that if no user-configurable gpg.minTrustLevel is set, then the old behavior of rejecting TRUST_UNDEFINED and TRUST_NEVER is enforced. If, on the other hand, gpg.minTrustLevel is set, then that value overrides the old behavior. Similarly, the %G? format specifier will continue show 'U' for signatures made with a key that has a trust level of TRUST_UNDEFINED or TRUST_NEVER, even though the 'U' character no longer exist in the `result` member of the signature_check structure. A new format specifier, %GT, is also introduced for users that want to show all possible trust levels for a signature. Another approach would have been to simply drop the trust-level requirement in verify_merge_signature(). This would also have made the behavior consistent with other parts of git that perform signature verification. However, requiring a minimum trust level for signing keys does seem to have a real-world use-case. For example, the build system used by the Qubes OS project currently parses the raw output from verify-tag in order to assert a minimum trust level for keys used to sign git tags [2]. [1] https://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=blob;f=doc/doc/DETAILS;h=bd00006e933ac56719b1edd2478ecd79273eae72;hb=refs/heads/master [2] https://github.com/QubesOS/qubes-builder/blob/9674c1991deef45b1a1b1c71fddfab14ba50dccf/scripts/verify-git-tag#L43 Signed-off-by: Hans Jerry Illikainen <hji@dyntopia.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-30gpg-interface: prefer check_signature() for GPG verificationLibravatar Hans Jerry Illikainen1-48/+49
This commit refactors the use of verify_signed_buffer() outside of gpg-interface.c to use check_signature() instead. It also turns verify_signed_buffer() into a file-local function since it's now only invoked internally by check_signature(). There were previously two globally scoped functions used in different parts of Git to perform GPG signature verification: verify_signed_buffer() and check_signature(). Now only check_signature() is used. The verify_signed_buffer() function doesn't guard against duplicate signatures as described by Michał Górny [1]. Instead it only ensures a non-erroneous exit code from GPG and the presence of at least one GOODSIG status field. This stands in contrast with check_signature() that returns an error if more than one signature is encountered. The lower degree of verification makes the use of verify_signed_buffer() problematic if callers don't parse and validate the various parts of the GPG status message themselves. And processing these messages seems like a task that should be reserved to gpg-interface.c with the function check_signature(). Furthermore, the use of verify_signed_buffer() makes it difficult to introduce new functionality that relies on the content of the GPG status lines. Now all operations that does signature verification share a single entry point to gpg-interface.c. This makes it easier to propagate changed or additional functionality in GPG signature verification to all parts of Git, without having odd edge-cases that don't perform the same degree of verification. [1] https://dev.gentoo.org/~mgorny/articles/attack-on-git-signature-verification.html Signed-off-by: Hans Jerry Illikainen <hji@dyntopia.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-23gpg-interface: limit search for primary key fingerprintLibravatar Hans Jerry Illikainen1-6/+18
The VALIDSIG status line from GnuPG with --status-fd is documented to have 9 required and 1 optional fields [1]. The final, and optional, field is used to specify the fingerprint of the primary key that made the signature in case it was made by a subkey. However, this field is only available for OpenPGP signatures; not for CMS/X.509. If the VALIDSIG status line does not have the optional 10th field, the current code will continue reading onto the next status line. And this is the case for non-OpenPGP signatures [1]. The consequence is that a subsequent status line may be considered as the "primary key" for signatures that does not have an actual primary key. Limit the search of these 9 or 10 fields to the single line to avoid this problem. If the 10th field is missing, report that there is no primary key fingerprint. [Reference] [1] GnuPG Details, General status codes https://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=blob;f=doc/DETAILS;h=6ce340e8c04794add995e84308bb3091450bd28f;hb=HEAD#l483 The documentation says: VALIDSIG <args> The args are: - <fingerprint_in_hex> - <sig_creation_date> - <sig-timestamp> - <expire-timestamp> - <sig-version> - <reserved> - <pubkey-algo> - <hash-algo> - <sig-class> - [ <primary-key-fpr> ] This status indicates that the signature is cryptographically valid. [...] PRIMARY-KEY-FPR is the fingerprint of the primary key or identical to the first argument. The primary-key-fpr parameter is used for OpenPGP and not available for CMS signatures. [...] Signed-off-by: Hans Jerry Illikainen <hji@dyntopia.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-23gpg-interface: refactor the free-and-xmemdupz patternLibravatar Hans Jerry Illikainen1-7/+15
Introduce a static replace_cstring() function to simplify repeated pattern of free-and-xmemdupz() for GPG status line parsing. This also helps us avoid potential memleaks if parsing of new status lines are introduced in the future. Signed-off-by: Hans Jerry Illikainen <hji@dyntopia.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-07-16gpg-interface: do not scan past the end of bufferLibravatar Steven Roberts1-0/+3
If the GPG output ends with trailing blank lines, after skipping them over inside the loop to find the terminating NUL at the end, the loop ends up looking for the next line, starting past the end. Signed-off-by: Steven Roberts <sroberts@fenderq.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-03Merge branch 'mg/gpg-fingerprint'Libravatar Junio C Hamano1-12/+45
New "--pretty=format:" placeholders %GF and %GP that show the GPG key fingerprints have been invented. * mg/gpg-fingerprint: gpg-interface.c: obtain primary key fingerprint as well gpg-interface.c: support getting key fingerprint via %GF format gpg-interface.c: use flags to determine key/signer info presence
2018-11-03Merge branch 'mg/gpg-parse-tighten'Libravatar Junio C Hamano1-29/+61
Detect and reject a signature block that has more than one GPG signature. * mg/gpg-parse-tighten: gpg-interface.c: detect and reject multiple signatures on commits
2018-10-23gpg-interface.c: obtain primary key fingerprint as wellLibravatar Michał Górny1-1/+15
Obtain the primary key fingerprint off VALIDSIG status message, and expose it via %GP format. Signed-off-by: Michał Górny <mgorny@gentoo.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-23gpg-interface.c: support getting key fingerprint via %GF formatLibravatar Michał Górny1-1/+13
Support processing VALIDSIG status that provides additional information for valid signatures. Use this information to propagate signing key fingerprint and expose it via %GF pretty format. This format can be used to build safer key verification systems that verify the key via complete fingerprint rather than short/long identifier provided by %GK. Signed-off-by: Michał Górny <mgorny@gentoo.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-23gpg-interface.c: use flags to determine key/signer info presenceLibravatar Michał Górny1-10/+17
Replace the logic used to determine whether key and signer information is present to use explicit flags in sigcheck_gpg_status[] array. This is more future-proof, since it makes it possible to add additional statuses without having to explicitly update the conditions. Signed-off-by: Michał Górny <mgorny@gentoo.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-22gpg-interface.c: detect and reject multiple signatures on commitsLibravatar Michał Górny1-29/+61
GnuPG supports creating signatures consisting of multiple signature packets. If such a signature is verified, it outputs all the status messages for each signature separately. However, git currently does not account for such scenario and gets terribly confused over getting multiple *SIG statuses. For example, if a malicious party alters a signed commit and appends a new untrusted signature, git is going to ignore the original bad signature and report untrusted commit instead. However, %GK and %GS format strings may still expand to the data corresponding to the original signature, potentially tricking the scripts into trusting the malicious commit. Given that the use of multiple signatures is quite rare, git does not support creating them without jumping through a few hoops, and finally supporting them properly would require extensive API improvement, it seems reasonable to just reject them at the moment. Signed-off-by: Michał Górny <mgorny@gentoo.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-20Merge branch 'jc/gpg-status'Libravatar Junio C Hamano1-1/+2
"git verify-tag" and "git verify-commit" have been taught to use the exit status of underlying "gpg --verify" to signal bad or untrusted signature they found. * jc/gpg-status: gpg-interface: propagate exit status from gpg back to the callers
2018-08-09gpg-interface: propagate exit status from gpg back to the callersLibravatar Junio C Hamano1-1/+2
When gpg-interface API unified support for signature verification codepaths for signed tags and signed commits in mid 2015 at around v2.6.0-rc0~114, we accidentally loosened the GPG signature verification. Before that change, signed commits were verified by looking for "G"ood signature from GPG, while ignoring the exit status of "gpg --verify" process, while signed tags were verified by simply passing the exit status of "gpg --verify" through. The unified code we currently have ignores the exit status of "gpg --verify" and returns successful verification when the signature matches an unexpired key regardless of the trust placed on the key (i.e. in addition to "G"ood ones, we accept "U"ntrusted ones). Make these commands signal failure with their exit status when underlying "gpg --verify" (or the custom command specified by "gpg.program" configuration variable) does so. This essentially changes their behaviour in a backward incompatible way to reject signatures that have been made with untrusted keys even if they correctly verify, as that is how "gpg --verify" behaves. Note that the code still overrides a zero exit status obtained from "gpg" (or gpg.program) if the output does not say the signature is good or computes correctly but made with untrusted keys, to catch a poorly written wrapper around "gpg" the user may give us. We could exclude "U"ntrusted support from this fallback code, but that would be making two backward incompatible changes in a single commit, so let's avoid that for now. A follow-up change could do so if desired. Helped-by: Vojtech Myslivec <vojtech.myslivec@nic.cz> Helped-by: brian m. carlson <sandals@crustytoothpaste.net> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-18gpg-interface: introduce new signature format "x509" using gpgsmLibravatar Henning Schild1-0/+15
This commit allows git to create and check x509 type signatures using gpgsm. Signed-off-by: Henning Schild <henning.schild@siemens.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-18gpg-interface: introduce new config to select per gpg format programLibravatar Henning Schild1-1/+1
Supporting multiple signing formats we will have the need to configure a custom program each. Add a new config value to cater for that. Signed-off-by: Henning Schild <henning.schild@siemens.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-18gpg-interface: do not hardcode the key string len anymoreLibravatar Henning Schild1-3/+4
gnupg does print the keyid followed by a space and the signer comes next. The same pattern is also used in gpgsm, but there the key length would be 40 instead of 16. Instead of hardcoding the expected length, find the first space and calculate it. Input that does not match the expected format will be ignored now, before we jumped to found+17 which might have been behind the end of an unexpected string. Signed-off-by: Henning Schild <henning.schild@siemens.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-18gpg-interface: introduce an abstraction for multiple gpg formatsLibravatar Henning Schild1-21/+67
Create a struct that holds the format details for the supported formats. At the moment that is still just "openpgp". This commit prepares for the introduction of more formats, that might use other programs and match other signatures. Signed-off-by: Henning Schild <henning.schild@siemens.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-17gpg-interface: add new config to select how to sign a commitLibravatar Henning Schild1-0/+10
Add "gpg.format" where the user can specify which type of signature to use for commits. At the moment only "openpgp" is supported and the value is not even used. This commit prepares for a new types of signatures. Signed-off-by: Henning Schild <henning.schild@siemens.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-11gpg-interface: make parse_gpg_output static and remove from interface headerLibravatar Henning Schild1-1/+1
Turn parse_gpg_output into a static function, the only outside user was migrated in an earlier commit. Signed-off-by: Henning Schild <henning.schild@siemens.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-16gpg-interface: find the last gpg signature lineLibravatar Jeff King1-3/+9
A signed tag has a detached signature like this: object ... [...more header...] This is the tag body. -----BEGIN PGP SIGNATURE----- [opaque gpg data] -----END PGP SIGNATURE----- Our parser finds the _first_ line that appears to start a PGP signature block, meaning we may be confused by a signature (or a signature-like line) in the actual body. Let's keep parsing and always find the final block, which should be the detached signature over all of the preceding content. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Ben Toews <mastahyeti@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-16gpg-interface: extract gpg line matching helperLibravatar Jeff King1-2/+7
Let's separate the actual line-by-line parsing of signatures from the notion of "is this a gpg signature line". That will make it easier to do more refactoring of this loop in future patches. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Ben Toews <mastahyeti@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-16gpg-interface: fix const-correctness of "eol" pointerLibravatar Jeff King1-2/+1
We accidentally shed the "const" of our buffer by passing it through memchr. Let's fix that, and while we're at it, move our variable declaration inside the loop, which is the only place that uses it. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Ben Toews <mastahyeti@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>