[CHORE] Use github.com/ProtonMail/go-crypto

- We were previously using `github.com/keybase/go-crypto`, because the
package for openpgp by Go itself is deprecated and no longer
maintained. This library provided a maintained version of the openpgp
package. However, it hasn't seen any activity for the last five years,
and I would therefore consider this also unmaintained.
- This patch switches the package to `github.com/ProtonMail/go-crypto`
which provides a maintained version of the openpgp package and was
already being used in the tests.
- Adds unit tests, I've carefully checked the callstacks to ensure the
OpenPGP-related code was covered under either a unit test or integration
tests to avoid regression, as this can easily turn into security
vulnerabilities if a regression happens here.
- Small behavior update, revocations are now checked correctly instead
of checking if they merely exist and the expiry time of a subkey is used
if one is provided (this is just cosmetic and doesn't impact security).
- One more dependency eliminated :D

assets/go-licenses.json

···
     "licenseText": "Copyright (c) 2017 Kevin Burke.\n\nPermission is hereby granted, free of charge, to any person\nobtaining a copy of this software and associated documentation\nfiles (the \"Software\"), to deal in the Software without\nrestriction, including without limitation the rights to use,\ncopy, modify, merge, publish, distribute, sublicense, and/or sell\ncopies of the Software, and to permit persons to whom the\nSoftware is furnished to do so, subject to the following\nconditions:\n\nThe above copyright notice and this permission notice shall be\nincluded in all copies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND,\nEXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES\nOF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND\nNONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT\nHOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,\nWHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING\nFROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR\nOTHER DEALINGS IN THE SOFTWARE.\n\n===================\n\nThe lexer and parser borrow heavily from github.com/pelletier/go-toml. The\nlicense for that project is copied below.\n\nThe MIT License (MIT)\n\nCopyright (c) 2013 - 2017 Thomas Pelletier, Eric Anderton\n\nPermission is hereby granted, free of charge, to any person obtaining a copy\nof this software and associated documentation files (the \"Software\"), to deal\nin the Software without restriction, including without limitation the rights\nto use, copy, modify, merge, publish, distribute, sublicense, and/or sell\ncopies of the Software, and to permit persons to whom the Software is\nfurnished to do so, subject to the following conditions:\n\nThe above copyright notice and this permission notice shall be included in all\ncopies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\nIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\nFITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\nAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\nLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\nOUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\nSOFTWARE.\n"
   },
   {
-    "name": "github.com/keybase/go-crypto",
-    "path": "github.com/keybase/go-crypto/LICENSE",
-    "licenseText": "Copyright (c) 2009 The Go Authors. All rights reserved.\n\nRedistribution and use in source and binary forms, with or without\nmodification, are permitted provided that the following conditions are\nmet:\n\n   * Redistributions of source code must retain the above copyright\nnotice, this list of conditions and the following disclaimer.\n   * Redistributions in binary form must reproduce the above\ncopyright notice, this list of conditions and the following disclaimer\nin the documentation and/or other materials provided with the\ndistribution.\n   * Neither the name of Google Inc. nor the names of its\ncontributors may be used to endorse or promote products derived from\nthis software without specific prior written permission.\n\nTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n\"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\nLIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\nA PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\nOWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\nSPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\nLIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\nDATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\nTHEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\nOF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n"
-  },
-  {
     "name": "github.com/klauspost/compress",
     "path": "github.com/klauspost/compress/LICENSE",
     "licenseText": "Copyright (c) 2012 The Go Authors. All rights reserved.\nCopyright (c) 2019 Klaus Post. All rights reserved.\n\nRedistribution and use in source and binary forms, with or without\nmodification, are permitted provided that the following conditions are\nmet:\n\n   * Redistributions of source code must retain the above copyright\nnotice, this list of conditions and the following disclaimer.\n   * Redistributions in binary form must reproduce the above\ncopyright notice, this list of conditions and the following disclaimer\nin the documentation and/or other materials provided with the\ndistribution.\n   * Neither the name of Google Inc. nor the names of its\ncontributors may be used to endorse or promote products derived from\nthis software without specific prior written permission.\n\nTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n\"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\nLIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\nA PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\nOWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\nSPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\nLIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\nDATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\nTHEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\nOF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n\n------------------\n\nFiles: gzhttp/*\n\n                                 Apache License\n                           Version 2.0, January 2004\n                        http://www.apache.org/licenses/\n\n   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION\n\n   1. Definitions.\n\n      \"License\" shall mean the terms and conditions for use, reproduction,\n      and distribution as defined by Sections 1 through 9 of this document.\n\n      \"Licensor\" shall mean the copyright owner or entity authorized by\n      the copyright owner that is granting the License.\n\n      \"Legal Entity\" shall mean the union of the acting entity and all\n      other entities that control, are controlled by, or are under common\n      control with that entity. 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While redistributing\n      the Work or Derivative Works thereof, You may choose to offer,\n      and charge a fee for, acceptance of support, warranty, indemnity,\n      or other liability obligations and/or rights consistent with this\n      License. However, in accepting such obligations, You may act only\n      on Your own behalf and on Your sole responsibility, not on behalf\n      of any other Contributor, and only if You agree to indemnify,\n      defend, and hold each Contributor harmless for any liability\n      incurred by, or claims asserted against, such Contributor by reason\n      of your accepting any such warranty or additional liability.\n\n   END OF TERMS AND CONDITIONS\n\n   APPENDIX: How to apply the Apache License to your work.\n\n      To apply the Apache License to your work, attach the following\n      boilerplate notice, with the fields enclosed by brackets \"[]\"\n      replaced with your own identifying information. (Don't include\n      the brackets!)  The text should be enclosed in the appropriate\n      comment syntax for the file format. We also recommend that a\n      file or class name and description of purpose be included on the\n      same \"printed page\" as the copyright notice for easier\n      identification within third-party archives.\n\n   Copyright 2016-2017 The New York Times Company\n\n   Licensed under the Apache License, Version 2.0 (the \"License\");\n   you may not use this file except in compliance with the License.\n   You may obtain a copy of the License at\n\n       http://www.apache.org/licenses/LICENSE-2.0\n\n   Unless required by applicable law or agreed to in writing, software\n   distributed under the License is distributed on an \"AS IS\" BASIS,\n   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n   See the License for the specific language governing permissions and\n   limitations under the License.\n\n------------------\n\nFiles: s2/cmd/internal/readahead/*\n\nThe MIT License (MIT)\n\nCopyright (c) 2015 Klaus Post\n\nPermission is hereby granted, free of charge, to any person obtaining a copy\nof this software and associated documentation files (the \"Software\"), to deal\nin the Software without restriction, including without limitation the rights\nto use, copy, modify, merge, publish, distribute, sublicense, and/or sell\ncopies of the Software, and to permit persons to whom the Software is\nfurnished to do so, subject to the following conditions:\n\nThe above copyright notice and this permission notice shall be included in all\ncopies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\nIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,\nFITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE\nAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER\nLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,\nOUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE\nSOFTWARE.\n\n---------------------\nFiles: snappy/*\nFiles: internal/snapref/*\n\nCopyright (c) 2011 The Snappy-Go Authors. All rights reserved.\n\nRedistribution and use in source and binary forms, with or without\nmodification, are permitted provided that the following conditions are\nmet:\n\n   * Redistributions of source code must retain the above copyright\nnotice, this list of conditions and the following disclaimer.\n   * Redistributions in binary form must reproduce the above\ncopyright notice, this list of conditions and the following disclaimer\nin the documentation and/or other materials provided with the\ndistribution.\n   * Neither the name of Google Inc. nor the names of its\ncontributors may be used to endorse or promote products derived from\nthis software without specific prior written permission.\n\nTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n\"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\nLIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\nA PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\nOWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\nSPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\nLIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\nDATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\nTHEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\nOF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n\n-----------------\n\nFiles: s2/cmd/internal/filepathx/*\n\nCopyright 2016 The filepathx Authors\n\nPermission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the \"Software\"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:\n\nThe above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\n"

go.mod

···
 	github.com/jhillyerd/enmime v1.2.0
 	github.com/json-iterator/go v1.1.12
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51
-	github.com/keybase/go-crypto v0.0.0-20200123153347-de78d2cb44f4
 	github.com/klauspost/compress v1.17.9
 	github.com/klauspost/cpuid/v2 v2.2.8
 	github.com/lib/pq v1.10.9

go.sum

···
 github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51/go.mod h1:CzGEWj7cYgsdH8dAjBGEr58BoE7ScuLd+fwFZ44+/x8=
 github.com/kevinburke/ssh_config v1.2.0 h1:x584FjTGwHzMwvHx18PXxbBVzfnxogHaAReU4gf13a4=
 github.com/kevinburke/ssh_config v1.2.0/go.mod h1:CT57kijsi8u/K/BOFA39wgDQJ9CxiF4nAY/ojJ6r6mM=
-github.com/keybase/go-crypto v0.0.0-20200123153347-de78d2cb44f4 h1:cTxwSmnaqLoo+4tLukHoB9iqHOu3LmLhRmgUxZo6Vp4=
-github.com/keybase/go-crypto v0.0.0-20200123153347-de78d2cb44f4/go.mod h1:ghbZscTyKdM07+Fw3KSi0hcJm+AlEUWj8QLlPtijN/M=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.4.1/go.mod h1:RyIbtBH6LamlWaDj8nUwkbUhJ87Yi3uG0guNDohfE1A=

models/asymkey/gpg_key.go

···
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/timeutil"
 
-	"github.com/keybase/go-crypto/openpgp"
-	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
 	"xorm.io/builder"
 )
 
···
 	// Parse Subkeys
 	subkeys := make([]*GPGKey, len(e.Subkeys))
 	for i, k := range e.Subkeys {
-		subs, err := parseSubGPGKey(ownerID, pubkey.KeyIdString(), k.PublicKey, expiry)
+		subKeyExpiry := expiry
+		if k.Sig.KeyLifetimeSecs != nil {
+			subKeyExpiry = k.PublicKey.CreationTime.Add(time.Duration(*k.Sig.KeyLifetimeSecs) * time.Second)
+		}
+
+		subs, err := parseSubGPGKey(ownerID, pubkey.KeyIdString(), k.PublicKey, subKeyExpiry)
 		if err != nil {
 			return nil, ErrGPGKeyParsing{ParseError: err}
 		}
···
 
 	emails := make([]*user_model.EmailAddress, 0, len(e.Identities))
 	for _, ident := range e.Identities {
-		if ident.Revocation != nil {
+		// Check if the identity is revoked.
+		if ident.Revoked(time.Now()) {
 			continue
 		}
 		email := strings.ToLower(strings.TrimSpace(ident.UserId.Email))

models/asymkey/gpg_key_add.go

···
 	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/modules/log"
 
-	"github.com/keybase/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp"
 )
 
 //   __________________  ________   ____  __.
···
 	verified := false
 	// Handle provided signature
 	if signature != "" {
-		signer, err := openpgp.CheckArmoredDetachedSignature(ekeys, strings.NewReader(token), strings.NewReader(signature))
+		signer, err := openpgp.CheckArmoredDetachedSignature(ekeys, strings.NewReader(token), strings.NewReader(signature), nil)
 		if err != nil {
-			signer, err = openpgp.CheckArmoredDetachedSignature(ekeys, strings.NewReader(token+"\n"), strings.NewReader(signature))
+			signer, err = openpgp.CheckArmoredDetachedSignature(ekeys, strings.NewReader(token+"\n"), strings.NewReader(signature), nil)
 		}
 		if err != nil {
-			signer, err = openpgp.CheckArmoredDetachedSignature(ekeys, strings.NewReader(token+"\r\n"), strings.NewReader(signature))
+			signer, err = openpgp.CheckArmoredDetachedSignature(ekeys, strings.NewReader(token+"\r\n"), strings.NewReader(signature), nil)
 		}
 		if err != nil {
 			log.Error("Unable to validate token signature. Error: %v", err)

models/asymkey/gpg_key_common.go

···
 	"strings"
 	"time"
 
-	"github.com/keybase/go-crypto/openpgp"
-	"github.com/keybase/go-crypto/openpgp/armor"
-	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp/armor"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
 )
 
 //   __________________  ________   ____  __.
···
 	for _, ident := range e.Identities {
 		if selfSig == nil {
 			selfSig = ident.SelfSignature
-		} else if ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId {
+		} else if ident.SelfSignature != nil && ident.SelfSignature.IsPrimaryId != nil && *ident.SelfSignature.IsPrimaryId {
 			selfSig = ident.SelfSignature
 			break
 		}

models/asymkey/gpg_key_object_verification.go

···
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 
-	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
 )
 
 // This file provides functions related to object (commit, tag) verification

models/asymkey/gpg_key_test.go

···
 	"code.gitea.io/gitea/modules/timeutil"
 	"code.gitea.io/gitea/modules/util"
 
-	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
 	"github.com/stretchr/testify/assert"
 )
 
···
 			assert.Equal(t, "[e-mail]", key.Emails[0].Email)
 		}
 	}
+}
+
+func TestCheckGPGRevokedIdentity(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+
+	assert.NoError(t, db.Insert(db.DefaultContext, &user_model.EmailAddress{UID: 1, Email: "[e-mail]", IsActivated: true}))
+	assert.NoError(t, db.Insert(db.DefaultContext, &user_model.EmailAddress{UID: 1, Email: "[e-mail]", IsActivated: true}))
+	_ = unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
+
+	revokedUserKey := `-----BEGIN PGP PUBLIC KEY BLOCK-----
+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+b2tlZEBnb2xhbmcuY29tPokBNgQwAQoAIBYhBOSJOSS3Dcepeq2X8NaBcvSOnFKD
+BQJbIDv3Ah0AAAoJENaBcvSOnFKDfWMIAKhI/Tvu3h8fSUxp/gSAcduT6bC1JttG
+0lYQ5ilKB/58lBUA5CO3ZrKDKlzW3M8VEcvohVaqeTMKeoQd5rCZq8KxHn/KvN6N
+s85REfXfniCKfAbnGgVXX3kDmZ1g63pkxrFu0fDZjVDXC6vy+I0sGyI/Inro0Pzb
+tvn0QCsxjapKK15BtmSrpgHgzVqVg0cUp8vqZeKFxarYbYB2idtGRci4b9tObOK0
+BSTVFy26+I/mrFGaPrySYiy2Kz5NMEcRhjmTxJ8jSwEr2O2sUR0yjbgUAXbTxDVE
+/jg5fQZ1ACvBRQnB7LvMHcInbzjyeTM3FazkkSYQD6b97+dkWwb1iWG5AQ0EWyA7
+kQEIALkg04REDZo1JgdYV4x8HJKFS4xAYWbIva1ZPqvDNmZRUbQZR2+gpJGEwn7z
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+snLUNd1Xu5EWEF2OdFkZ2a1qYdxBvAYdQf4+1Nr+NRIx1u1NS9c8jp3PuMOkrQEi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+=IKnw
+-----END PGP PUBLIC KEY BLOCK-----
+`
+
+	keys, err := AddGPGKey(db.DefaultContext, 1, revokedUserKey, "", "")
+	assert.NoError(t, err)
+	assert.Len(t, keys, 1)
+	assert.Len(t, keys[0].Emails, 1)
+	assert.EqualValues(t, "[e-mail]", keys[0].Emails[0].Email)
+
+	primaryKeyID := "D68172F48E9C5283"
+	// Assert primary key
+	unittest.AssertExistsAndLoadBean(t, &GPGKey{OwnerID: 1, KeyID: primaryKeyID, Content: "xsBNBFsgO5EBCADhREPmcjsPkXe1z7ctvyWL0S7oa9JaoGZ9oPDHFDlQxd0qlX2eDZJZDg0qYvVixmaULIulApq1puEsaJCn3lHUbHlb4PYKwLEywYXM28JN91KtLsz/uaEX2KC5WqeP40utmzkNLq+oRX/xnRMgwbO7yUNVG2UlEa6eI+xOXO3YtLdmJMBWClQ066ZnOIzEo1JxnIwha1CDBMWLLfOLrg6l8InUqaXbtEBbnaIYO6fXVXELUjkxnmk7t/QOk0tXCy8muH9UDqJkwDUESY2l79XwBAcx9riX8vY7vwC34pm22fAUVLCJx1SJx0J8bkeNp38jKM2Zd9SUQqSbfBopQ4pPABEBAAE="})
+	// Assert subkey
+	unittest.AssertExistsAndLoadBean(t, &GPGKey{OwnerID: 1, KeyID: "2C56900BE5486AF8", PrimaryKeyID: primaryKeyID, Content: "zsBNBFsgO5EBCAC5INOERA2aNSYHWFeMfByShUuMQGFmyL2tWT6rwzZmUVG0GUdvoKSRhMJ+81aHxr5zmIhluegEuY99UhX+ZK6NftW2UOYjjjQZ4NPDjqOfP5dYUbHiCFRgeUxkmjwnQoSih63iSOoUt5kocR+oXXxbYmbgeOa8KGgKzDLGHI2nsy8Cni3N/enKVMMHGbJy1DXdV7uRFhBdjnRZGdmtamHcQbwGHUH+PtTa/jUSMdbtTUvXPI6dz7jDpK0BImzbXNb+r9CcudpiixuMu5gv3qyJL5EAWCXcT2j+y2VWj2HN/8bJHMoo6yf+bn6A/Cu9f0obbGVF0kJ/Y5UWmEdBG6IzABEBAAE="})
 }
 
 func TestCheckGParseGPGExpire(t *testing.T) {

release-notes/4506.md

···
+Replaced the openpgp library to use a maintained version, github.com/ProtonMail/go-crypto. This change also went hand in hand with doing correct revocation checks (instead of merely checking if a revocation signature existed) and using the expiration of a subkey if one existed instead of always using the expiration of the default key.

routers/web/user/home.go

···
 	issue_service "code.gitea.io/gitea/services/issue"
 	pull_service "code.gitea.io/gitea/services/pull"
 
-	"github.com/keybase/go-crypto/openpgp"
-	"github.com/keybase/go-crypto/openpgp/armor"
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp/armor"
 	"xorm.io/builder"
 )
 

services/packages/debian/repository.go

···
 	"code.gitea.io/gitea/modules/util"
 	packages_service "code.gitea.io/gitea/services/packages"
 
-	"github.com/keybase/go-crypto/openpgp"
-	"github.com/keybase/go-crypto/openpgp/armor"
-	"github.com/keybase/go-crypto/openpgp/clearsign"
-	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp/armor"
+	"github.com/ProtonMail/go-crypto/openpgp/clearsign"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
 	"github.com/ulikunitz/xz"
 )
 

services/packages/rpm/repository.go

···
 	"code.gitea.io/gitea/modules/util"
 	packages_service "code.gitea.io/gitea/services/packages"
 
-	"github.com/keybase/go-crypto/openpgp"
-	"github.com/keybase/go-crypto/openpgp/armor"
-	"github.com/keybase/go-crypto/openpgp/packet"
+	"github.com/ProtonMail/go-crypto/openpgp"
+	"github.com/ProtonMail/go-crypto/openpgp/armor"
+	"github.com/ProtonMail/go-crypto/openpgp/packet"
 )
 
 // GetOrCreateRepositoryVersion gets or creates the internal repository package

tests/integration/user_test.go

···
 
 
 =twTO
------END PGP PUBLIC KEY BLOCK-----
-`)
+-----END PGP PUBLIC KEY BLOCK-----`)
 	// Import key
 	// User1 <[e-mail]>
 	session := loginUser(t, "user1")
···
 7XhJ1v6JYuh8kaYaEz8OpZDeh7f6Ho6PzJrsy/TKTKhGgZNINj1iaPFyOkQgKR5M
 GrE0MHOxUbc9tbtyk0F1SuzREUBH
 =DDXw
------END PGP PUBLIC KEY BLOCK-----
-`)
+-----END PGP PUBLIC KEY BLOCK-----`)
 	// Export new key
 	testExportUserGPGKeys(t, "user1", `-----BEGIN PGP PUBLIC KEY BLOCK-----
 
···
 7XhJ1v6JYuh8kaYaEz8OpZDeh7f6Ho6PzJrsy/TKTKhGgZNINj1iaPFyOkQgKR5M
 GrE0MHOxUbc9tbtyk0F1SuzREUBH
 =WFf5
------END PGP PUBLIC KEY BLOCK-----
-`)
+-----END PGP PUBLIC KEY BLOCK-----`)
 }
 
 func testExportUserGPGKeys(t *testing.T, user, expected string) {