Add crypto.Signer support for KMS/HSM keys

.github/workflows/lint.yml

@@ -13,7 +13,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
         with:
-          go-version: stable
+          go-version-file: go.mod
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v7
         with:

go.mod

@@ -1,19 +1,19 @@
 module github.com/crewjam/saml
 
-go 1.22
+go 1.24.0
 
 require (
-	github.com/golang-jwt/jwt/v5 v5.2.2
 	github.com/beevik/etree v1.5.0
+	github.com/golang-jwt/jwt/v5 v5.3.1
 	github.com/google/go-cmp v0.7.0
 	github.com/mattermost/xml-roundtrip-validator v0.1.0
-	github.com/russellhaering/goxmldsig v1.4.0
-	golang.org/x/crypto v0.33.0
+	github.com/russellhaering/goxmldsig v1.5.0
+	golang.org/x/crypto v0.48.0
 	gotest.tools v2.2.0+incompatible
 )
 
 require (
-	github.com/jonboulle/clockwork v0.2.2 // indirect
+	github.com/jonboulle/clockwork v0.5.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/stretchr/testify v1.10.0 // indirect
 )

go.sum

@@ -1,45 +1,30 @@
-github.com/beevik/etree v1.1.0/go.mod h1:r8Aw8JqVegEf0w2fDnATrX9VpkMcyFeM0FhwO62wh+A=
 github.com/beevik/etree v1.5.0 h1:iaQZFSDS+3kYZiGoc9uKeOkUY3nYMXOKLl6KIJxiJWs=
 github.com/beevik/etree v1.5.0/go.mod h1:gPNJNaBGVZ9AwsidazFZyygnd+0pAU38N4D+WemwKNs=
-github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/golang-jwt/jwt/v5 v5.2.2 h1:Rl4B7itRWVtYIHFrSNd7vhTiz9UpLdi6gZhZ3wEeDy8=
-github.com/golang-jwt/jwt/v5 v5.2.2/go.mod h1:pqrtFR0X4osieyHYxtmOUWsAWrfe1Q5UVIyoH402zdk=
+github.com/golang-jwt/jwt/v5 v5.3.1 h1:kYf81DTWFe7t+1VvL7eS+jKFVWaUnK9cB1qbwn63YCY=
+github.com/golang-jwt/jwt/v5 v5.3.1/go.mod h1:fxCRLWMO43lRc8nhHWY6LGqRcf+1gQWArsqaEUEa5bE=
 github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
 github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
-github.com/jonboulle/clockwork v0.2.2 h1:UOGuzwb1PwsrDAObMuhUnj0p5ULPj8V/xJ7Kx9qUBdQ=
-github.com/jonboulle/clockwork v0.2.2/go.mod h1:Pkfl5aHPm1nk2H9h0bjmnJD/BcgbGXUBGnn1kMkgxc8=
-github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
-github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
-github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk=
-github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
-github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
-github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/jonboulle/clockwork v0.5.0 h1:Hyh9A8u51kptdkR+cqRpT1EebBwTn1oK9YfGYbdFz6I=
+github.com/jonboulle/clockwork v0.5.0/go.mod h1:3mZlmanh0g2NDKO5TWZVJAfofYk64M7XN3SzBPjZF60=
 github.com/mattermost/xml-roundtrip-validator v0.1.0 h1:RXbVD2UAl7A7nOTR4u7E3ILa4IbtvKBHw64LDsmu9hU=
 github.com/mattermost/xml-roundtrip-validator v0.1.0/go.mod h1:qccnGMcpgwcNaBnxqpJpWWUiPNr5H3O8eDgGV9gT5To=
-github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/rogpeppe/go-internal v1.6.1/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc=
-github.com/rogpeppe/go-internal v1.8.0/go.mod h1:WmiCO8CzOY8rg0OYDC4/i/2WRWAB6poM+XZ2dLUbcbE=
-github.com/russellhaering/goxmldsig v1.4.0 h1:8UcDh/xGyQiyrW+Fq5t8f+l2DLB1+zlhYzkPUJ7Qhys=
-github.com/russellhaering/goxmldsig v1.4.0/go.mod h1:gM4MDENBQf7M+V824SGfyIUVFWydB7n0KkEubVJl+Tw=
+github.com/russellhaering/goxmldsig v1.5.0 h1:AU2UkkYIUOTyZRbe08XMThaOCelArgvNfYapcmSjBNw=
+github.com/russellhaering/goxmldsig v1.5.0/go.mod h1:x98CjQNFJcWfMxeOrMnMKg70lvDP6tE0nTaeUnjXDmk=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
-golang.org/x/crypto v0.33.0 h1:IOBPskki6Lysi0lo9qQvbxiQ+FvsCC/YWOecCHAixus=
-golang.org/x/crypto v0.33.0/go.mod h1:bVdXmD7IV/4GdElGPozy6U7lWdRXA4qyRVGJV57uQ5M=
+golang.org/x/crypto v0.48.0 h1:/VRzVqiRSggnhY7gNRxPauEQ5Drw9haKdM0jqfcCFts=
+golang.org/x/crypto v0.48.0/go.mod h1:r0kV5h3qnFPlQnBSrULhlsRfryS2pmewsg+XfMgkVos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
-gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools v2.2.0+incompatible h1:VsBPFP1AI068pPrMxtb/S8Zkgf9xEmTLJjfM+P5UIEo=

samlsp/middleware_test.go

@@ -2,6 +2,11 @@ package samlsp
 
 import (
 	"bytes"
+	"crypto"
+	"crypto/ecdsa"
+	"crypto/ed25519"
+	"crypto/elliptic"
+	"crypto/rand"
 	"crypto/rsa"
 	"crypto/sha256"
 	"crypto/x509"
@@ -17,6 +22,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/golang-jwt/jwt/v5"
 	dsig "github.com/russellhaering/goxmldsig"
 	"gotest.tools/assert"
 	is "gotest.tools/assert/cmp"
@@ -520,3 +526,268 @@ func TestMiddlewareHandlesInvalidResponse(t *testing.T) {
 	assert.Check(t, is.Equal("", resp.Header().Get("Location")))
 	assert.Check(t, is.Equal("", resp.Header().Get("Set-Cookie")))
 }
+
+type mockSigner struct {
+	signer crypto.Signer
+}
+
+func (m *mockSigner) Public() crypto.PublicKey {
+	return m.signer.Public()
+}
+
+func (m *mockSigner) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
+	return m.signer.Sign(rand, digest, opts)
+}
+
+func newMockRSASigner(t *testing.T) crypto.Signer {
+	key := mustParsePrivateKey(golden.Get(t, "key.pem"))
+	return &mockSigner{signer: key.(crypto.Signer)}
+}
+
+func TestMiddleware_WithCryptoSignerE2E(t *testing.T) {
+	origTimeNow := saml.TimeNow
+	origClock := saml.Clock
+	origRandReader := saml.RandReader
+	t.Cleanup(func() {
+		saml.TimeNow = origTimeNow
+		saml.Clock = origClock
+		saml.RandReader = origRandReader
+	})
+
+	saml.TimeNow = func() time.Time {
+		rv, _ := time.Parse("Mon Jan 2 15:04:05.999999999 MST 2006", "Mon Dec 1 01:57:09.123456789 UTC 2015")
+		return rv
+	}
+	saml.Clock = dsig.NewFakeClockAt(saml.TimeNow())
+	saml.RandReader = &testRandomReader{}
+
+	cert := mustParseCertificate(golden.Get(t, "cert.pem"))
+	idpMetadata := golden.Get(t, "idp_metadata.xml")
+
+	var metadata saml.EntityDescriptor
+	if err := xml.Unmarshal(idpMetadata, &metadata); err != nil {
+		panic(err)
+	}
+
+	mockSigner := newMockRSASigner(t)
+
+	opts := Options{
+		URL:         mustParseURL("https://15661444.ngrok.io/"),
+		Key:         mockSigner,
+		Certificate: cert,
+		IDPMetadata: &metadata,
+	}
+
+	middleware, err := New(opts)
+	assert.Check(t, err)
+
+	sessionProvider := DefaultSessionProvider(opts)
+	sessionProvider.Name = "ttt"
+	sessionProvider.MaxAge = 7200 * time.Second
+
+	sessionCodec := sessionProvider.Codec.(JWTSessionCodec)
+	sessionCodec.MaxAge = 7200 * time.Second
+	sessionProvider.Codec = sessionCodec
+
+	middleware.Session = sessionProvider
+	middleware.ServiceProvider.MetadataURL.Path = "/saml2/metadata"
+	middleware.ServiceProvider.AcsURL.Path = "/saml2/acs"
+	middleware.ServiceProvider.SloURL.Path = "/saml2/slo"
+
+	t.Run("SessionEncodeDecode", func(t *testing.T) {
+		var tc JWTSessionClaims
+		if err := json.Unmarshal(golden.Get(t, "token.json"), &tc); err != nil {
+			t.Fatal(err)
+		}
+
+		encoded, err := sessionProvider.Codec.Encode(tc)
+		assert.Check(t, err)
+		assert.Assert(t, encoded != "")
+
+		decoded, err := sessionProvider.Codec.Decode(encoded)
+		assert.Check(t, err)
+		decodedClaims := decoded.(JWTSessionClaims)
+		assert.Equal(t, tc.Subject, decodedClaims.Subject)
+	})
+
+	t.Run("TrackedRequestEncodeDecode", func(t *testing.T) {
+		codec := middleware.RequestTracker.(CookieRequestTracker).Codec
+		trackedReq := TrackedRequest{
+			Index:         "test-index",
+			SAMLRequestID: "test-request-id",
+			URI:           "/test-uri",
+		}
+
+		encoded, err := codec.Encode(trackedReq)
+		assert.Check(t, err)
+		assert.Assert(t, encoded != "")
+
+		decoded, err := codec.Decode(encoded)
+		assert.Check(t, err)
+		assert.Equal(t, trackedReq.Index, decoded.Index)
+		assert.Equal(t, trackedReq.SAMLRequestID, decoded.SAMLRequestID)
+	})
+
+	t.Run("RequireAccountFlow", func(t *testing.T) {
+		handler := middleware.RequireAccount(
+			http.HandlerFunc(func(_ http.ResponseWriter, _ *http.Request) {
+				panic("not reached")
+			}))
+
+		req, _ := http.NewRequest("GET", "/protected", nil)
+		resp := httptest.NewRecorder()
+		handler.ServeHTTP(resp, req)
+
+		assert.Check(t, is.Equal(http.StatusFound, resp.Code))
+		assert.Assert(t, resp.Header().Get("Location") != "")
+		assert.Assert(t, resp.Header().Get("Set-Cookie") != "")
+	})
+
+	t.Run("Metadata", func(t *testing.T) {
+		req, _ := http.NewRequest("GET", "/saml2/metadata", nil)
+		resp := httptest.NewRecorder()
+		middleware.ServeHTTP(resp, req)
+
+		assert.Check(t, is.Equal(http.StatusOK, resp.Code))
+		assert.Check(t, is.Equal("application/samlmetadata+xml",
+			resp.Header().Get("Content-type")))
+		golden.Assert(t, resp.Body.String(), "expected_middleware_metadata.xml")
+	})
+}
+
+func TestJWTSessionCodec_CryptoSignerEncodeDecode(t *testing.T) {
+	tests := []struct {
+		name    string
+		method  jwt.SigningMethod
+		genKey  func(t *testing.T) crypto.Signer
+		subject string
+	}{
+		{
+			name:   "ECDSA-P256",
+			method: jwt.SigningMethodES256,
+			genKey: func(t *testing.T) crypto.Signer {
+				k, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+				assert.Check(t, err)
+				return k
+			},
+			subject: "test-ecdsa-p256",
+		},
+		{
+			name:   "ECDSA-P384",
+			method: jwt.SigningMethodES384,
+			genKey: func(t *testing.T) crypto.Signer {
+				k, err := ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
+				assert.Check(t, err)
+				return k
+			},
+			subject: "test-ecdsa-p384",
+		},
+		{
+			name:   "ECDSA-P521",
+			method: jwt.SigningMethodES512,
+			genKey: func(t *testing.T) crypto.Signer {
+				k, err := ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
+				assert.Check(t, err)
+				return k
+			},
+			subject: "test-ecdsa-p521",
+		},
+		{
+			name:   "RSA-PSS",
+			method: jwt.SigningMethodPS256,
+			genKey: func(t *testing.T) crypto.Signer {
+				k, err := rsa.GenerateKey(rand.Reader, 2048)
+				assert.Check(t, err)
+				return k
+			},
+			subject: "test-rsa-pss",
+		},
+		{
+			name:   "EdDSA",
+			method: jwt.SigningMethodEdDSA,
+			genKey: func(t *testing.T) crypto.Signer {
+				_, k, err := ed25519.GenerateKey(rand.Reader)
+				assert.Check(t, err)
+				return k
+			},
+			subject: "test-eddsa",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			now := time.Now()
+			origTimeNow := saml.TimeNow
+			t.Cleanup(func() { saml.TimeNow = origTimeNow })
+			saml.TimeNow = func() time.Time { return now }
+
+			signer := &mockSigner{signer: tt.genKey(t)}
+
+			audience := "https://example.com/"
+			codec := JWTSessionCodec{
+				SigningMethod: tt.method,
+				Audience:      audience,
+				Issuer:        audience,
+				MaxAge:        time.Hour,
+				Key:           signer,
+			}
+
+			tc := JWTSessionClaims{
+				RegisteredClaims: jwt.RegisteredClaims{
+					Audience:  jwt.ClaimStrings{audience},
+					Issuer:    audience,
+					Subject:   tt.subject,
+					IssuedAt:  jwt.NewNumericDate(now),
+					ExpiresAt: jwt.NewNumericDate(now.Add(time.Hour)),
+					NotBefore: jwt.NewNumericDate(now),
+				},
+				SAMLSession: true,
+			}
+
+			encoded, err := codec.Encode(tc)
+			assert.Check(t, err)
+			assert.Assert(t, encoded != "")
+
+			decoded, err := codec.Decode(encoded)
+			assert.Check(t, err)
+			decodedClaims := decoded.(JWTSessionClaims)
+			assert.Equal(t, tt.subject, decodedClaims.Subject)
+		})
+	}
+}
+
+func TestJWTSessionCodec_UnsupportedAlgorithmReturnsError(t *testing.T) {
+	now := time.Now()
+	origTimeNow := saml.TimeNow
+	t.Cleanup(func() { saml.TimeNow = origTimeNow })
+	saml.TimeNow = func() time.Time { return now }
+
+	rsaKey, err := rsa.GenerateKey(rand.Reader, 2048)
+	assert.Check(t, err)
+
+	signer := &mockSigner{signer: rsaKey}
+
+	audience := "https://example.com/"
+	codec := JWTSessionCodec{
+		SigningMethod: jwt.SigningMethodNone,
+		Audience:      audience,
+		Issuer:        audience,
+		MaxAge:        time.Hour,
+		Key:           signer,
+	}
+
+	tc := JWTSessionClaims{
+		RegisteredClaims: jwt.RegisteredClaims{
+			Audience:  jwt.ClaimStrings{audience},
+			Issuer:    audience,
+			Subject:   "test",
+			IssuedAt:  jwt.NewNumericDate(now),
+			ExpiresAt: jwt.NewNumericDate(now.Add(time.Hour)),
+			NotBefore: jwt.NewNumericDate(now),
+		},
+		SAMLSession: true,
+	}
+
+	_, err = codec.Encode(tc)
+	assert.Check(t, is.ErrorContains(err, "unsupported algorithm for crypto.Signer"))
+}