forgejo/models/asymkey/ssh_key_object_verification_test.go
Gusted b55c72828e feat(sec): Add SSH signing support for instances (#6897)
- Add support to set `gpg.format` in the Git config, via the new `[repository.signing].FORMAT` option. This is to tell Git that the instance would like to use SSH instead of OpenPGP to sign its commits. This is guarded behind a Git version check for v2.34.0 and a check that a `ssh-keygen` binary is present.
- Add support to recognize the public SSH key that is given to `[repository.signing].SIGNING_KEY` as the signing key by the instance.
- Thus this allows the instance to use SSH commit signing for commits that the instance creates (e.g. initial and squash commits) instead of using PGP.
- Technically (although I have no clue how as this is not documented) you can have a different PGP signing key for different repositories; this is not implemented for SSH signing.
- Add unit and integration testing.
  - `TestInstanceSigning` was reworked from `TestGPGGit`, now also includes testing for SHA256 repositories. Is the main integration test that actually signs commits and checks that they are marked as verified by Forgejo.
  - `TestParseCommitWithSSHSignature` is a unit test that makes sure that if a SSH instnace signing key is set, that it is used to possibly verify instance SSH signed commits.
  - `TestSyncConfigGPGFormat` is a unit test that makes sure the correct git config is set according to the signing format setting. Also checks that the guarded git version check and ssh-keygen binary presence check is done correctly.
  - `TestSSHInstanceKey` is a unit test that makes sure the parsing of a SSH signing key is done correctly.
  - `TestAPISSHSigningKey` is a integration test that makes sure the newly added API route `/api/v1/signing-key.ssh` responds correctly.

Documentation PR: forgejo/docs#1122

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/6897
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: Gusted <postmaster@gusted.xyz>
Co-committed-by: Gusted <postmaster@gusted.xyz>
2025-04-11 13:25:35 +00:00

194 lines
6.8 KiB
Go

// Copyright 2023 The Forgejo Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package asymkey
import (
"os"
"testing"
"forgejo.org/models/db"
"forgejo.org/models/unittest"
user_model "forgejo.org/models/user"
"forgejo.org/modules/git"
"forgejo.org/modules/setting"
"forgejo.org/modules/test"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"golang.org/x/crypto/ssh"
)
func TestParseCommitWithSSHSignature(t *testing.T) {
require.NoError(t, unittest.PrepareTestDatabase())
user2 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
sshKey := unittest.AssertExistsAndLoadBean(t, &PublicKey{ID: 1000, OwnerID: 2})
t.Run("No commiter", func(t *testing.T) {
o := commitToGitObject(&git.Commit{})
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, &user_model.User{})
assert.False(t, commitVerification.Verified)
assert.Equal(t, NoKeyFound, commitVerification.Reason)
})
t.Run("Commiter without keys", func(t *testing.T) {
user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
o := commitToGitObject(&git.Commit{Committer: &git.Signature{Email: user.Email}})
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, user)
assert.False(t, commitVerification.Verified)
assert.Equal(t, NoKeyFound, commitVerification.Reason)
})
t.Run("Correct signature with wrong email", func(t *testing.T) {
gitCommit := &git.Commit{
Committer: &git.Signature{
Email: "non-existent",
},
Signature: &git.ObjectSignature{
Payload: `tree 2d491b2985a7ff848d5c02748e7ea9f9f7619f9f
parent 45b03601635a1f463b81963a4022c7f87ce96ef9
author user2 <non-existent> 1699710556 +0100
committer user2 <non-existent> 1699710556 +0100
Using email that isn't known to Forgejo
`,
Signature: `-----BEGIN SSH SIGNATURE-----
U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAgoGSe9Zy7Ez9bSJcaTNjh/Y7p95
f5DujjqkpzFRtw6CEAAAADZ2l0AAAAAAAAAAZzaGE1MTIAAABTAAAAC3NzaC1lZDI1NTE5
AAAAQIMufOuSjZeDUujrkVK4sl7ICa0WwEftas8UAYxx0Thdkiw2qWjR1U1PKfTLm16/w8
/bS1LX1lZNuzm2LR2qEgw=
-----END SSH SIGNATURE-----
`,
},
}
o := commitToGitObject(gitCommit)
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, user2)
assert.False(t, commitVerification.Verified)
assert.Equal(t, NoKeyFound, commitVerification.Reason)
})
t.Run("Incorrect signature with correct email", func(t *testing.T) {
gitCommit := &git.Commit{
Committer: &git.Signature{
Email: "user2@example.com",
},
Signature: &git.ObjectSignature{
Payload: `tree 853694aae8816094a0d875fee7ea26278dbf5d0f
parent c2780d5c313da2a947eae22efd7dacf4213f4e7f
author user2 <user2@example.com> 1699707877 +0100
committer user2 <user2@example.com> 1699707877 +0100
Add content
`,
Signature: `-----BEGIN SSH SIGNATURE-----`,
},
}
o := commitToGitObject(gitCommit)
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, user2)
assert.False(t, commitVerification.Verified)
assert.Equal(t, NoKeyFound, commitVerification.Reason)
})
t.Run("Valid signature with correct email", func(t *testing.T) {
gitCommit := &git.Commit{
Committer: &git.Signature{
Email: "user2@example.com",
},
Signature: &git.ObjectSignature{
Payload: `tree 853694aae8816094a0d875fee7ea26278dbf5d0f
parent c2780d5c313da2a947eae22efd7dacf4213f4e7f
author user2 <user2@example.com> 1699707877 +0100
committer user2 <user2@example.com> 1699707877 +0100
Add content
`,
Signature: `-----BEGIN SSH SIGNATURE-----
U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAgoGSe9Zy7Ez9bSJcaTNjh/Y7p95
f5DujjqkpzFRtw6CEAAAADZ2l0AAAAAAAAAAZzaGE1MTIAAABTAAAAC3NzaC1lZDI1NTE5
AAAAQBe2Fwk/FKY3SBCnG6jSYcO6ucyahp2SpQ/0P+otslzIHpWNW8cQ0fGLdhhaFynJXQ
fs9cMpZVM9BfIKNUSO8QY=
-----END SSH SIGNATURE-----
`,
},
}
o := commitToGitObject(gitCommit)
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, user2)
assert.True(t, commitVerification.Verified)
assert.Equal(t, "user2 / SHA256:TKfwbZMR7e9OnlV2l1prfah1TXH8CmqR0PvFEXVCXA4", commitVerification.Reason)
assert.Equal(t, sshKey, commitVerification.SigningSSHKey)
})
t.Run("Valid signature with noreply email", func(t *testing.T) {
defer test.MockVariableValue(&setting.Service.NoReplyAddress, "noreply.example.com")()
gitCommit := &git.Commit{
Committer: &git.Signature{
Email: "user2@noreply.example.com",
},
Signature: &git.ObjectSignature{
Payload: `tree 4836c7f639f37388bab4050ef5c97bbbd54272fc
parent 795be1b0117ea5c65456050bb9fd84744d4fd9c6
author user2 <user2@noreply.example.com> 1699709594 +0100
committer user2 <user2@noreply.example.com> 1699709594 +0100
Commit with noreply
`,
Signature: `-----BEGIN SSH SIGNATURE-----
U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAgoGSe9Zy7Ez9bSJcaTNjh/Y7p95
f5DujjqkpzFRtw6CEAAAADZ2l0AAAAAAAAAAZzaGE1MTIAAABTAAAAC3NzaC1lZDI1NTE5
AAAAQJz83KKxD6Bz/ZvNpqkA3RPOSQ4LQ5FfEItbtoONkbwV9wAWMnmBqgggo/lnXCJ3oq
muPLbvEduU+Ze/1Ol1pgk=
-----END SSH SIGNATURE-----
`,
},
}
o := commitToGitObject(gitCommit)
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, user2)
assert.True(t, commitVerification.Verified)
assert.Equal(t, "user2 / SHA256:TKfwbZMR7e9OnlV2l1prfah1TXH8CmqR0PvFEXVCXA4", commitVerification.Reason)
assert.Equal(t, sshKey, commitVerification.SigningSSHKey)
})
t.Run("Instance key", func(t *testing.T) {
pubKeyContent, err := os.ReadFile("../../tests/integration/ssh-signing-key.pub")
require.NoError(t, err)
pubKey, _, _, _, err := ssh.ParseAuthorizedKey(pubKeyContent)
require.NoError(t, err)
defer test.MockVariableValue(&setting.Repository.Signing.SigningName, "UwU")()
defer test.MockVariableValue(&setting.Repository.Signing.SigningEmail, "fox@example.com")()
defer test.MockVariableValue(&setting.SSHInstanceKey, pubKey)()
gitCommit := &git.Commit{
Committer: &git.Signature{
Email: "fox@example.com",
},
Signature: &git.ObjectSignature{
Payload: `tree f96f1a4f1a51dc42e2983592f503980b60b8849c
parent 93f84db542dd8c6e952c8130bc2fcbe2e299b8b4
author OwO <instance@example.com> 1738961379 +0100
committer UwU <fox@example.com> 1738961379 +0100
Fox
`,
Signature: `-----BEGIN SSH SIGNATURE-----
U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAgV5ELwZ8XJe2LLR/UTuEu/vsFdb
t7ry0W8hyzz/b1iocAAAADZ2l0AAAAAAAAAAZzaGE1MTIAAABTAAAAC3NzaC1lZDI1NTE5
AAAAQCnyMRkWVVNoZxZkvi/ZoknUhs4LNBmEwZs9e9214WIt+mhKfc6BiHoE2qeluR2McD
Y5RzHnA8Ke9wXddEePCQE=
-----END SSH SIGNATURE-----
`,
},
}
o := commitToGitObject(gitCommit)
commitVerification := ParseObjectWithSSHSignature(db.DefaultContext, &o, user2)
assert.True(t, commitVerification.Verified)
assert.Equal(t, "UwU / SHA256:QttK41r/zMUeAW71b5UgVSb8xGFF/DlZJ6TyADW+uoI", commitVerification.Reason)
assert.Equal(t, "SHA256:QttK41r/zMUeAW71b5UgVSb8xGFF/DlZJ6TyADW+uoI", commitVerification.SigningSSHKey.Fingerprint)
})
}