From e528e2b435466bd854b1f7a4619bdc16c058b8ba Mon Sep 17 00:00:00 2001 From: Wim Date: Sun, 5 Jun 2022 09:16:14 +0200 Subject: [PATCH] Implement http signatures support for the API (#17565) Fixes #12338 This allows use to talk to the API with our ssh certificate (and/or ssh-agent) without needing to fetch an API key or tokens. It will just automatically work when users have added their ssh principal in gitea. This needs client code in tea Update: also support normal pubkeys ref: https://tools.ietf.org/html/draft-cavage-http-signatures Co-authored-by: Lunny Xiao Co-authored-by: zeripath Signed-off-by: Andrew Thornton --- go.mod | 1 + go.sum | 2 + integrations/api_httpsig_test.go | 137 +++++++++++++++++++ integrations/mssql.ini.tmpl | 1 + integrations/mysql.ini.tmpl | 1 + integrations/mysql8.ini.tmpl | 1 + integrations/pgsql.ini.tmpl | 1 + integrations/sqlite.ini.tmpl | 1 + modules/ssh/ssh.go | 3 +- routers/api/v1/api.go | 1 + services/auth/httpsign.go | 217 +++++++++++++++++++++++++++++++ 11 files changed, 365 insertions(+), 1 deletion(-) create mode 100644 integrations/api_httpsig_test.go create mode 100644 services/auth/httpsign.go diff --git a/go.mod b/go.mod index 82d137d360..ed86dcdd9f 100644 --- a/go.mod +++ b/go.mod @@ -29,6 +29,7 @@ require ( github.com/go-chi/chi/v5 v5.0.7 github.com/go-chi/cors v1.2.1 github.com/go-enry/go-enry/v2 v2.8.2 + github.com/go-fed/httpsig v1.1.0 github.com/go-git/go-billy/v5 v5.3.1 github.com/go-git/go-git/v5 v5.4.3-0.20210630082519-b4368b2a2ca4 github.com/go-ldap/ldap/v3 v3.4.3 diff --git a/go.sum b/go.sum index d351992b1b..e962391334 100644 --- a/go.sum +++ b/go.sum @@ -468,6 +468,8 @@ github.com/go-enry/go-enry/v2 v2.8.2 h1:uiGmC+3K8sVd/6DOe2AOJEOihJdqda83nPyJNtMR github.com/go-enry/go-enry/v2 v2.8.2/go.mod h1:GVzIiAytiS5uT/QiuakK7TF1u4xDab87Y8V5EJRpsIQ= github.com/go-enry/go-oniguruma v1.2.1 h1:k8aAMuJfMrqm/56SG2lV9Cfti6tC4x8673aHCcBk+eo= github.com/go-enry/go-oniguruma v1.2.1/go.mod h1:bWDhYP+S6xZQgiRL7wlTScFYBe023B6ilRZbCAD5Hf4= +github.com/go-fed/httpsig v1.1.0 h1:9M+hb0jkEICD8/cAiNqEB66R87tTINszBRTjwjQzWcI= +github.com/go-fed/httpsig v1.1.0/go.mod h1:RCMrTZvN1bJYtofsG4rd5NaO5obxQ5xBkdiS7xsT7bM= github.com/go-git/gcfg v1.5.0 h1:Q5ViNfGF8zFgyJWPqYwA7qGFoMTEiBmdlkcfRmpIMa4= github.com/go-git/gcfg v1.5.0/go.mod h1:5m20vg6GwYabIxaOonVkTdrILxQMpEShl1xiMF4ua+E= github.com/go-git/go-billy/v5 v5.2.0/go.mod h1:pmpqyWchKfYfrkb/UVH4otLvyi/5gJlGI4Hb3ZqZ3W0= diff --git a/integrations/api_httpsig_test.go b/integrations/api_httpsig_test.go new file mode 100644 index 0000000000..7197e9afb9 --- /dev/null +++ b/integrations/api_httpsig_test.go @@ -0,0 +1,137 @@ +// Copyright 2022 The Gitea Authors. All rights reserved. +// Use of this source code is governed by a MIT-style +// license that can be found in the LICENSE file. + +package integrations + +import ( + "encoding/base64" + "fmt" + "net/http" + "net/url" + "testing" + + api "code.gitea.io/gitea/modules/structs" + + "github.com/go-fed/httpsig" + "golang.org/x/crypto/ssh" +) + +const ( + httpsigPrivateKey = `-----BEGIN OPENSSH PRIVATE KEY----- +b3BlbnNzaC1rZXktdjEAAAAABG5vbmUAAAAEbm9uZQAAAAAAAAABAAABFwAAAAdzc2gtcn +NhAAAAAwEAAQAAAQEAqjmQeb5Eb1xV7qbNf9ErQ0XRvKZWzUsLFhJzZz+Ab7q8WtPs91vQ +fBiypw4i8OTG6WzDcgZaV8Ndxn7iHnIstdA1k89MVG4stydymmwmk9+mrCMNsu5OmdIy9F +AZ61RDcKuf5VG2WKkmeK0VO+OMJIYfE1C6czNeJ6UAmcIOmhGxvjMI83XUO9n0ftwTwayp ++XU5prvKx/fTvlPjbraPNU4OzwPjVLqXBzpoXYhBquPaZYFRVyvfFZLObYsmy+BrsxcloM +l+9w4P0ATJ9njB7dRDL+RrN4uhhYSihqOK4w4vaiOj1+aA0eC0zXunEfLXfGIVQ/FhWcCy +5f72mMiKnQAAA9AxSmzFMUpsxQAAAAdzc2gtcnNhAAABAQCqOZB5vkRvXFXups1/0StDRd +G8plbNSwsWEnNnP4Bvurxa0+z3W9B8GLKnDiLw5MbpbMNyBlpXw13GfuIeciy10DWTz0xU +biy3J3KabCaT36asIw2y7k6Z0jL0UBnrVENwq5/lUbZYqSZ4rRU744wkhh8TULpzM14npQ +CZwg6aEbG+MwjzddQ72fR+3BPBrKn5dTmmu8rH99O+U+Nuto81Tg7PA+NUupcHOmhdiEGq +49plgVFXK98Vks5tiybL4GuzFyWgyX73Dg/QBMn2eMHt1EMv5Gs3i6GFhKKGo4rjDi9qI6 +PX5oDR4LTNe6cR8td8YhVD8WFZwLLl/vaYyIqdAAAAAwEAAQAAAQBz+nyBNi2SYir6SxPA +flcnoq5gBkUl4ndPNosCUbXEakpi5/mQHzJRGtK+F1efIYCVEdGoIsPy/90onNKbQ9dKmO +2oI5kx/U7iCzJ+HCm8nqkEp21x+AP9scWdx+Wg/OxmG8j5iU7f4X+gwOyyvTqCuA78Lgia +7Oi9wiJCoIEqXr6dRYGJzfASwKA2dj995HzATexleLSD5fQCmZTF+Vh5OQ5WmE+c53JdZS +T3Plie/P/smgSWBtf1fWr6JL2+EBsqQsIK1Jo7r/7rxsz+ILoVfnneNQY4QSa9W+t6ZAI+ +caSA0Guv7vC92ewjlMVlwKa3XaEjMJb5sFlg1r6TYMwBAAAAgQDQwXvgSXNaSHIeH53/Ab +t4BlNibtxK8vY8CZFloAKXkjrivKSlDAmQCM0twXOweX2ScPjE+XlSMV4AUsv/J6XHGHci +W3+PGIBfc/fQRBpiyhzkoXYDVrlkSKHffCnAqTUQlYkhr0s7NkZpEeqPE0doAUs4dK3Iqb +zdtz8e5BPXZwAAAIEA4U/JskIu5Oge8Is2OLOhlol0EJGw5JGodpFyhbMC+QYK9nYqy7wI +a6mZ2EfOjjwIZD/+wYyulw6cRve4zXwgzUEXLIKp8/H3sYvJK2UMeP7y68sQFqGxbm6Rnh +tyBBSaJQnOXVOFf9gqZGCyO/J0Illg3AXTuC8KS/cxwasC38EAAACBAMFo/6XQoR6E3ynj +VBaz2SilWqQBixUyvcNz8LY73IIDCecoccRMFSEKhWtvlJijxvFbF9M8g9oKAVPuub4V5r +CGmwVPEd5yt4C2iyV0PhLp1PA2/i42FpCSnHaz/EXSz6ncTZcOMMuDqUbgUUpQg4VSUDl9 +fhTNAzWwZoQ91aHdAAAAFHUwMDIyMTQ2QGljdHMtcC1ueC03AQIDBAUG +-----END OPENSSH PRIVATE KEY-----` + httpsigCertificate = `ssh-rsa-cert-v01@openssh.com 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` +) + +func TestHTTPSigPubKey(t *testing.T) { + // Add our public key to user1 + defer prepareTestEnv(t)() + session := loginUser(t, "user1") + token := url.QueryEscape(getTokenForLoggedInUser(t, session)) + keysURL := fmt.Sprintf("/api/v1/user/keys?token=%s", token) + keyType := "ssh-rsa" + keyContent := "AAAAB3NzaC1yc2EAAAADAQABAAABAQCqOZB5vkRvXFXups1/0StDRdG8plbNSwsWEnNnP4Bvurxa0+z3W9B8GLKnDiLw5MbpbMNyBlpXw13GfuIeciy10DWTz0xUbiy3J3KabCaT36asIw2y7k6Z0jL0UBnrVENwq5/lUbZYqSZ4rRU744wkhh8TULpzM14npQCZwg6aEbG+MwjzddQ72fR+3BPBrKn5dTmmu8rH99O+U+Nuto81Tg7PA+NUupcHOmhdiEGq49plgVFXK98Vks5tiybL4GuzFyWgyX73Dg/QBMn2eMHt1EMv5Gs3i6GFhKKGo4rjDi9qI6PX5oDR4LTNe6cR8td8YhVD8WFZwLLl/vaYyIqd" + rawKeyBody := api.CreateKeyOption{ + Title: "test-key", + Key: keyType + " " + keyContent, + } + req := NewRequestWithJSON(t, "POST", keysURL, rawKeyBody) + session.MakeRequest(t, req, http.StatusCreated) + + // parse our private key and create the httpsig request + sshSigner, _ := ssh.ParsePrivateKey([]byte(httpsigPrivateKey)) + keyID := ssh.FingerprintSHA256(sshSigner.PublicKey()) + + // create the request + req = NewRequest(t, "GET", "/api/v1/admin/users") + + signer, _, err := httpsig.NewSSHSigner(sshSigner, httpsig.DigestSha512, []string{httpsig.RequestTarget, "(created)", "(expires)"}, httpsig.Signature, 10) + if err != nil { + t.Fatal(err) + } + + // sign the request + err = signer.SignRequest(keyID, req, nil) + if err != nil { + t.Fatal(err) + } + + // make the request + MakeRequest(t, req, http.StatusOK) +} + +func TestHTTPSigCert(t *testing.T) { + // Add our public key to user1 + defer prepareTestEnv(t)() + session := loginUser(t, "user1") + + csrf := GetCSRF(t, session, "/user/settings/keys") + req := NewRequestWithValues(t, "POST", "/user/settings/keys", map[string]string{ + "_csrf": csrf, + "content": "user1", + "title": "principal", + "type": "principal", + }) + + session.MakeRequest(t, req, http.StatusSeeOther) + pkcert, _, _, _, err := ssh.ParseAuthorizedKey([]byte(httpsigCertificate)) + if err != nil { + t.Fatal(err) + } + + // parse our private key and create the httpsig request + sshSigner, _ := ssh.ParsePrivateKey([]byte(httpsigPrivateKey)) + keyID := "gitea" + + // create our certificate signer using the ssh signer and our certificate + certSigner, err := ssh.NewCertSigner(pkcert.(*ssh.Certificate), sshSigner) + if err != nil { + t.Fatal(err) + } + + // create the request + req = NewRequest(t, "GET", "/api/v1/admin/users") + + // add our cert to the request + certString := base64.RawStdEncoding.EncodeToString(pkcert.(*ssh.Certificate).Marshal()) + req.Header.Add("x-ssh-certificate", certString) + + signer, _, err := httpsig.NewSSHSigner(certSigner, httpsig.DigestSha512, []string{httpsig.RequestTarget, "(created)", "(expires)", "x-ssh-certificate"}, httpsig.Signature, 10) + if err != nil { + t.Fatal(err) + } + + // sign the request + err = signer.SignRequest(keyID, req, nil) + if err != nil { + t.Fatal(err) + } + + // make the request + MakeRequest(t, req, http.StatusOK) +} diff --git a/integrations/mssql.ini.tmpl b/integrations/mssql.ini.tmpl index b076bb863c..da15e9ef69 100644 --- a/integrations/mssql.ini.tmpl +++ b/integrations/mssql.ini.tmpl @@ -49,6 +49,7 @@ OFFLINE_MODE = false LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w APP_DATA_PATH = integrations/gitea-integration-mssql/data BUILTIN_SSH_SERVER_USER = git +SSH_TRUSTED_USER_CA_KEYS = ssh-rsa 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 [attachment] PATH = integrations/gitea-integration-mssql/data/attachments diff --git a/integrations/mysql.ini.tmpl b/integrations/mysql.ini.tmpl index 6a0fd4ab86..4df4933642 100644 --- a/integrations/mysql.ini.tmpl +++ b/integrations/mysql.ini.tmpl @@ -51,6 +51,7 @@ OFFLINE_MODE = false LFS_START_SERVER = true LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w +SSH_TRUSTED_USER_CA_KEYS = ssh-rsa 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 [lfs] MINIO_BASE_PATH = lfs/ diff --git a/integrations/mysql8.ini.tmpl b/integrations/mysql8.ini.tmpl index 16f8851fe5..4b63dd51a1 100644 --- a/integrations/mysql8.ini.tmpl +++ b/integrations/mysql8.ini.tmpl @@ -49,6 +49,7 @@ OFFLINE_MODE = false LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w APP_DATA_PATH = integrations/gitea-integration-mysql8/data BUILTIN_SSH_SERVER_USER = git +SSH_TRUSTED_USER_CA_KEYS = ssh-rsa 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 [attachment] PATH = integrations/gitea-integration-mysql8/data/attachments diff --git a/integrations/pgsql.ini.tmpl b/integrations/pgsql.ini.tmpl index 5c4fbcc829..5b54a02c9f 100644 --- a/integrations/pgsql.ini.tmpl +++ b/integrations/pgsql.ini.tmpl @@ -50,6 +50,7 @@ OFFLINE_MODE = false LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w APP_DATA_PATH = integrations/gitea-integration-pgsql/data BUILTIN_SSH_SERVER_USER = git +SSH_TRUSTED_USER_CA_KEYS = ssh-rsa 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 [attachment] PATH = integrations/gitea-integration-pgsql/data/attachments diff --git a/integrations/sqlite.ini.tmpl b/integrations/sqlite.ini.tmpl index c180148891..2da7fd65d3 100644 --- a/integrations/sqlite.ini.tmpl +++ b/integrations/sqlite.ini.tmpl @@ -46,6 +46,7 @@ LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w APP_DATA_PATH = integrations/gitea-integration-sqlite/data ENABLE_GZIP = true BUILTIN_SSH_SERVER_USER = git +SSH_TRUSTED_USER_CA_KEYS = ssh-rsa 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 [attachment] PATH = integrations/gitea-integration-sqlite/data/attachments diff --git a/modules/ssh/ssh.go b/modules/ssh/ssh.go index a240c01319..2affeb781a 100644 --- a/modules/ssh/ssh.go +++ b/modules/ssh/ssh.go @@ -188,8 +188,9 @@ func publicKeyHandler(ctx ssh.Context, key ssh.PublicKey) bool { c := &gossh.CertChecker{ IsUserAuthority: func(auth gossh.PublicKey) bool { + marshaled := auth.Marshal() for _, k := range setting.SSH.TrustedUserCAKeysParsed { - if bytes.Equal(auth.Marshal(), k.Marshal()) { + if bytes.Equal(marshaled, k.Marshal()) { return true } } diff --git a/routers/api/v1/api.go b/routers/api/v1/api.go index 1492ef07a7..03f7a57d5c 100644 --- a/routers/api/v1/api.go +++ b/routers/api/v1/api.go @@ -592,6 +592,7 @@ func bind(obj interface{}) http.HandlerFunc { func buildAuthGroup() *auth.Group { group := auth.NewGroup( &auth.OAuth2{}, + &auth.HTTPSign{}, &auth.Basic{}, // FIXME: this should be removed once we don't allow basic auth in API ) if setting.Service.EnableReverseProxyAuth { diff --git a/services/auth/httpsign.go b/services/auth/httpsign.go new file mode 100644 index 0000000000..67053d2b77 --- /dev/null +++ b/services/auth/httpsign.go @@ -0,0 +1,217 @@ +// Copyright 2021 The Gitea Authors. All rights reserved. +// Use of this source code is governed by a MIT-style +// license that can be found in the LICENSE file. + +package auth + +import ( + "bytes" + "encoding/base64" + "errors" + "fmt" + "net/http" + "strings" + + asymkey_model "code.gitea.io/gitea/models/asymkey" + user_model "code.gitea.io/gitea/models/user" + "code.gitea.io/gitea/modules/log" + "code.gitea.io/gitea/modules/setting" + + "github.com/go-fed/httpsig" + "golang.org/x/crypto/ssh" +) + +// Ensure the struct implements the interface. +var ( + _ Method = &HTTPSign{} + _ Named = &HTTPSign{} +) + +// HTTPSign implements the Auth interface and authenticates requests (API requests +// only) by looking for http signature data in the "Signature" header. +// more information can be found on https://github.com/go-fed/httpsig +type HTTPSign struct{} + +// Name represents the name of auth method +func (h *HTTPSign) Name() string { + return "httpsign" +} + +// Verify extracts and validates HTTPsign from the Signature header of the request and returns +// the corresponding user object on successful validation. +// Returns nil if header is empty or validation fails. +func (h *HTTPSign) Verify(req *http.Request, w http.ResponseWriter, store DataStore, sess SessionStore) *user_model.User { + sigHead := req.Header.Get("Signature") + if len(sigHead) == 0 { + return nil + } + + var ( + publicKey *asymkey_model.PublicKey + err error + ) + + if len(req.Header.Get("X-Ssh-Certificate")) != 0 { + // Handle Signature signed by SSH certificates + if len(setting.SSH.TrustedUserCAKeys) == 0 { + return nil + } + + publicKey, err = VerifyCert(req) + if err != nil { + log.Debug("VerifyCert on request from %s: failed: %v", req.RemoteAddr, err) + log.Warn("Failed authentication attempt from %s", req.RemoteAddr) + return nil + } + } else { + // Handle Signature signed by Public Key + publicKey, err = VerifyPubKey(req) + if err != nil { + log.Debug("VerifyPubKey on request from %s: failed: %v", req.RemoteAddr, err) + log.Warn("Failed authentication attempt from %s", req.RemoteAddr) + return nil + } + } + + u, err := user_model.GetUserByID(publicKey.OwnerID) + if err != nil { + log.Error("GetUserByID: %v", err) + return nil + } + + store.GetData()["IsApiToken"] = true + + log.Trace("HTTP Sign: Logged in user %-v", u) + + return u +} + +func VerifyPubKey(r *http.Request) (*asymkey_model.PublicKey, error) { + verifier, err := httpsig.NewVerifier(r) + if err != nil { + return nil, fmt.Errorf("httpsig.NewVerifier failed: %s", err) + } + + keyID := verifier.KeyId() + + publicKeys, err := asymkey_model.SearchPublicKey(0, keyID) + if err != nil { + return nil, err + } + + if len(publicKeys) == 0 { + return nil, fmt.Errorf("no public key found for keyid %s", keyID) + } + + sshPublicKey, _, _, _, err := ssh.ParseAuthorizedKey([]byte(publicKeys[0].Content)) + if err != nil { + return nil, err + } + + if err := doVerify(verifier, []ssh.PublicKey{sshPublicKey}); err != nil { + return nil, err + } + + return publicKeys[0], nil +} + +// VerifyCert verifies the validity of the ssh certificate and returns the publickey of the signer +// We verify that the certificate is signed with the correct CA +// We verify that the http request is signed with the private key (of the public key mentioned in the certificate) +func VerifyCert(r *http.Request) (*asymkey_model.PublicKey, error) { + // Get our certificate from the header + bcert, err := base64.RawStdEncoding.DecodeString(r.Header.Get("x-ssh-certificate")) + if err != nil { + return nil, err + } + + pk, err := ssh.ParsePublicKey(bcert) + if err != nil { + return nil, err + } + + // Check if it's really a ssh certificate + cert, ok := pk.(*ssh.Certificate) + if !ok { + return nil, fmt.Errorf("no certificate found") + } + + c := &ssh.CertChecker{ + IsUserAuthority: func(auth ssh.PublicKey) bool { + marshaled := auth.Marshal() + + for _, k := range setting.SSH.TrustedUserCAKeysParsed { + if bytes.Equal(marshaled, k.Marshal()) { + return true + } + } + + return false + }, + } + + // check the CA of the cert + if !c.IsUserAuthority(cert.SignatureKey) { + return nil, fmt.Errorf("CA check failed") + } + + // Create a verifier + verifier, err := httpsig.NewVerifier(r) + if err != nil { + return nil, fmt.Errorf("httpsig.NewVerifier failed: %s", err) + } + + // now verify that this request was signed with the private key that matches the certificate public key + if err := doVerify(verifier, []ssh.PublicKey{cert.Key}); err != nil { + return nil, err + } + + // Now for each of the certificate valid principals + for _, principal := range cert.ValidPrincipals { + // Look in the db for the public key + publicKey, err := asymkey_model.SearchPublicKeyByContentExact(r.Context(), principal) + if asymkey_model.IsErrKeyNotExist(err) { + // No public key matches this principal - try the next principal + continue + } else if err != nil { + // this error will be a db error therefore we can't solve this and we should abort + log.Error("SearchPublicKeyByContentExact: %v", err) + return nil, err + } + + // Validate the cert for this principal + if err := c.CheckCert(principal, cert); err != nil { + // however, because principal is a member of ValidPrincipals - if this fails then the certificate itself is invalid + return nil, err + } + + // OK we have a public key for a principal matching a valid certificate whose key has signed this request. + return publicKey, nil + } + + // No public key matching a principal in the certificate is registered in gitea + return nil, fmt.Errorf("no valid principal found") +} + +// doVerify iterates across the provided public keys attempting the verify the current request against each key in turn +func doVerify(verifier httpsig.Verifier, sshPublicKeys []ssh.PublicKey) error { + for _, publicKey := range sshPublicKeys { + cryptoPubkey := publicKey.(ssh.CryptoPublicKey).CryptoPublicKey() + + var algos []httpsig.Algorithm + + switch { + case strings.HasPrefix(publicKey.Type(), "ssh-ed25519"): + algos = []httpsig.Algorithm{httpsig.ED25519} + case strings.HasPrefix(publicKey.Type(), "ssh-rsa"): + algos = []httpsig.Algorithm{httpsig.RSA_SHA1, httpsig.RSA_SHA256, httpsig.RSA_SHA512} + } + for _, algo := range algos { + if err := verifier.Verify(cryptoPubkey, algo); err == nil { + return nil + } + } + } + + return errors.New("verification failed") +}