Add changelog for 0.26.1 (#1812)

Fix CA startup with Vault RA configuration

CHANGELOG.md

@@ -25,6 +25,18 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ---
 
+## [0.26.1] - 2024-04-22
+
+### Added
+
+- Allow configuration of a custom SCEP key manager (smallstep/certificates#1797)
+
+### Fixed
+
+- id-scep-failInfoText OID (smallstep/certificates#1794)
+- CA startup with Vault RA configuration (smallstep/certificates#1803)
+
+
 ## [0.26.0] - 2024-03-28
 
 ### Added 

authority/authority.go

@@ -447,6 +447,7 @@ func (a *Authority) init() error {
 				return err
 			}
 			a.rootX509Certs = append(a.rootX509Certs, resp.RootCertificate)
+			a.intermediateX509Certs = append(a.intermediateX509Certs, resp.IntermediateCertificates...)
 		}
 	}
 
@@ -695,32 +696,42 @@ func (a *Authority) init() error {
 			options := &scep.Options{
 				Roots:         a.rootX509Certs,
 				Intermediates: a.intermediateX509Certs,
-				SignerCert:    a.intermediateX509Certs[0],
 			}
-			if options.Signer, err = a.keyManager.CreateSigner(&kmsapi.CreateSignerRequest{
-				SigningKey: a.config.IntermediateKey,
-				Password:   a.password,
-			}); err != nil {
-				return err
+
+			// intermediate certificates can be empty in RA mode
+			if len(a.intermediateX509Certs) > 0 {
+				options.SignerCert = a.intermediateX509Certs[0]
 			}
-			// TODO(hs): instead of creating the decrypter here, pass the
-			// intermediate key + chain down to the SCEP authority,
-			// and only instantiate it when required there. Is that possible?
-			// Also with entering passwords?
-			// TODO(hs): if moving the logic, try improving the logic for the
-			// decrypter password too? Right now it needs to be entered multiple
-			// times; I've observed it to be three times maximum, every time
-			// the intermediate key is read.
-			_, isRSA := options.Signer.Public().(*rsa.PublicKey)
-			if km, ok := a.keyManager.(kmsapi.Decrypter); ok && isRSA {
-				if decrypter, err := km.CreateDecrypter(&kmsapi.CreateDecrypterRequest{
-					DecryptionKey: a.config.IntermediateKey,
-					Password:      a.password,
-				}); err == nil {
-					// only pass the decrypter down when it was successfully created,
-					// meaning it's an RSA key, and `CreateDecrypter` did not fail.
-					options.Decrypter = decrypter
-					options.DecrypterCert = options.Intermediates[0]
+
+			// attempt to create the (default) SCEP signer if the intermediate
+			// key is configured.
+			if a.config.IntermediateKey != "" {
+				if options.Signer, err = a.keyManager.CreateSigner(&kmsapi.CreateSignerRequest{
+					SigningKey: a.config.IntermediateKey,
+					Password:   a.password,
+				}); err != nil {
+					return err
+				}
+
+				// TODO(hs): instead of creating the decrypter here, pass the
+				// intermediate key + chain down to the SCEP authority,
+				// and only instantiate it when required there. Is that possible?
+				// Also with entering passwords?
+				// TODO(hs): if moving the logic, try improving the logic for the
+				// decrypter password too? Right now it needs to be entered multiple
+				// times; I've observed it to be three times maximum, every time
+				// the intermediate key is read.
+				_, isRSAKey := options.Signer.Public().(*rsa.PublicKey)
+				if km, ok := a.keyManager.(kmsapi.Decrypter); ok && isRSAKey {
+					if decrypter, err := km.CreateDecrypter(&kmsapi.CreateDecrypterRequest{
+						DecryptionKey: a.config.IntermediateKey,
+						Password:      a.password,
+					}); err == nil {
+						// only pass the decrypter down when it was successfully created,
+						// meaning it's an RSA key, and `CreateDecrypter` did not fail.
+						options.Decrypter = decrypter
+						options.DecrypterCert = options.Intermediates[0]
+					}
 				}
 			}
 

cas/apiv1/requests.go

@@ -116,7 +116,8 @@ type GetCertificateAuthorityRequest struct {
 // GetCertificateAuthorityResponse is the response that contains
 // the root certificate.
 type GetCertificateAuthorityResponse struct {
-	RootCertificate *x509.Certificate
+	RootCertificate          *x509.Certificate
+	IntermediateCertificates []*x509.Certificate
 }
 
 // CreateKeyRequest is the request used to generate a new key using a KMS.

cas/vaultcas/vaultcas.go

@@ -165,7 +165,8 @@ func (v *VaultCAS) GetCertificateAuthority(*apiv1.GetCertificateAuthorityRequest
 	}
 
 	return &apiv1.GetCertificateAuthorityResponse{
-		RootCertificate: cert.root,
+		RootCertificate:          cert.root,
+		IntermediateCertificates: cert.intermediates,
 	}, nil
 }
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/smallstep/certificates
 
-go 1.20
+go 1.21
 
 require (
 	cloud.google.com/go/longrunning v0.5.6
@@ -16,7 +16,7 @@ require (
 	github.com/google/go-tpm v0.9.0
 	github.com/google/uuid v1.6.0
 	github.com/googleapis/gax-go/v2 v2.12.3
-	github.com/hashicorp/vault/api v1.12.2
+	github.com/hashicorp/vault/api v1.13.0
 	github.com/hashicorp/vault/api/auth/approle v0.6.0
 	github.com/hashicorp/vault/api/auth/kubernetes v0.6.0
 	github.com/newrelic/go-agent/v3 v3.32.0
@@ -38,15 +38,16 @@ require (
 	golang.org/x/crypto v0.22.0
 	golang.org/x/exp v0.0.0-20240318143956-a85f2c67cd81
 	golang.org/x/net v0.24.0
-	google.golang.org/api v0.172.0
+	google.golang.org/api v0.176.0
 	google.golang.org/grpc v1.63.2
 	google.golang.org/protobuf v1.33.0
 )
 
 require (
 	cloud.google.com/go v0.112.1 // indirect
-	cloud.google.com/go/compute v1.24.0 // indirect
-	cloud.google.com/go/compute/metadata v0.2.3 // indirect
+	cloud.google.com/go/auth v0.2.2 // indirect
+	cloud.google.com/go/auth/oauth2adapt v0.2.1 // indirect
+	cloud.google.com/go/compute/metadata v0.3.0 // indirect
 	cloud.google.com/go/iam v1.1.7 // indirect
 	cloud.google.com/go/kms v1.15.8 // indirect
 	filippo.io/edwards25519 v1.1.0 // indirect
@@ -85,6 +86,7 @@ require (
 	github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/go-jose/go-jose/v4 v4.0.1 // indirect
 	github.com/go-kit/kit v0.13.0 // indirect
 	github.com/go-kit/log v0.2.1 // indirect
 	github.com/go-logfmt/logfmt v0.6.0 // indirect
@@ -154,14 +156,13 @@ require (
 	go.opentelemetry.io/otel v1.24.0 // indirect
 	go.opentelemetry.io/otel/metric v1.24.0 // indirect
 	go.opentelemetry.io/otel/trace v1.24.0 // indirect
-	golang.org/x/oauth2 v0.18.0 // indirect
+	golang.org/x/oauth2 v0.19.0 // indirect
 	golang.org/x/sync v0.6.0 // indirect
 	golang.org/x/sys v0.19.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 	golang.org/x/time v0.5.0 // indirect
-	google.golang.org/appengine v1.6.8 // indirect
 	google.golang.org/genproto v0.0.0-20240227224415-6ceb2ff114de // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20240401170217-c3f982113cda // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240325203815-454cdb8f5daa // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240415180920-8c6c420018be // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,10 +1,12 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 cloud.google.com/go v0.112.1 h1:uJSeirPke5UNZHIb4SxfZklVSiWWVqW4oXlETwZziwM=
 cloud.google.com/go v0.112.1/go.mod h1:+Vbu+Y1UU+I1rjmzeMOb/8RfkKJK2Gyxi1X6jJCZLo4=
-cloud.google.com/go/compute v1.24.0 h1:phWcR2eWzRJaL/kOiJwfFsPs4BaKq1j6vnpZrc1YlVg=
-cloud.google.com/go/compute v1.24.0/go.mod h1:kw1/T+h/+tK2LJK0wiPPx1intgdAM3j/g3hFDlscY40=
-cloud.google.com/go/compute/metadata v0.2.3 h1:mg4jlk7mCAj6xXp9UJ4fjI9VUI5rubuGBW5aJ7UnBMY=
-cloud.google.com/go/compute/metadata v0.2.3/go.mod h1:VAV5nSsACxMJvgaAuX6Pk2AawlZn8kiOGuCv6gTkwuA=
+cloud.google.com/go/auth v0.2.2 h1:gmxNJs4YZYcw6YvKRtVBaF2fyUE6UrWPyzU8jHvYfmI=
+cloud.google.com/go/auth v0.2.2/go.mod h1:2bDNJWtWziDT3Pu1URxHHbkHE/BbOCuyUiKIGcNvafo=
+cloud.google.com/go/auth/oauth2adapt v0.2.1 h1:VSPmMmUlT8CkIZ2PzD9AlLN+R3+D1clXMWHHa6vG/Ag=
+cloud.google.com/go/auth/oauth2adapt v0.2.1/go.mod h1:tOdK/k+D2e4GEwfBRA48dKNQiDsqIXxLh7VU319eV0g=
+cloud.google.com/go/compute/metadata v0.3.0 h1:Tz+eQXMEqDIKRsmY3cHTL6FVaynIjX2QxYC4trgAKZc=
+cloud.google.com/go/compute/metadata v0.3.0/go.mod h1:zFmK7XCadkQkj6TtorcaGlCW1hT1fIilQDwofLpJ20k=
 cloud.google.com/go/iam v1.1.7 h1:z4VHOhwKLF/+UYXAJDFwGtNF0b6gjsW1Pk9Ml0U/IoM=
 cloud.google.com/go/iam v1.1.7/go.mod h1:J4PMPg8TtyurAUvSmPj8FF3EDgY1SPRZxcUGrn7WXGA=
 cloud.google.com/go/kms v1.15.8 h1:szIeDCowID8th2i8XE4uRev5PMxQFqW+JjwYxL9h6xs=
@@ -120,6 +122,7 @@ github.com/dgryski/go-farm v0.0.0-20190423205320-6a90982ecee2/go.mod h1:SqUrOPUn
 github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13 h1:fAjc9m62+UWV/WAFKLNi6ZS0675eEUC9y3AlwSbQu1Y=
 github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13/go.mod h1:SqUrOPUnsFjfmXRMNPybcSiG0BgUW2AuFH8PAnS2iTw=
 github.com/dnaeon/go-vcr v1.2.0 h1:zHCHvJYTMh1N7xnV7zf1m1GPBF9Ad0Jk/whtQ1663qI=
+github.com/dnaeon/go-vcr v1.2.0/go.mod h1:R4UdLID7HZT3taECzJs4YgbbH6PIGXB6W/sc5OLb6RQ=
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
@@ -129,6 +132,7 @@ github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1m
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fatih/color v1.16.0 h1:zmkK9Ngbjj+K0yRhTVONQh1p/HknKYSlNT+vZCzyokM=
+github.com/fatih/color v1.16.0/go.mod h1:fL2Sau1YI5c0pdGEVCbKQbLXB6edEj1ZgiY4NijnWvE=
 github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
@@ -139,6 +143,8 @@ github.com/go-chi/chi/v5 v5.0.12/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNIT
 github.com/go-jose/go-jose/v3 v3.0.1/go.mod h1:RNkWWRld676jZEYoV3+XK8L2ZnNSvIsxFMht0mSX+u8=
 github.com/go-jose/go-jose/v3 v3.0.3 h1:fFKWeig/irsp7XD2zBxvnmA/XaRWp5V3CBsZXJF7G7k=
 github.com/go-jose/go-jose/v3 v3.0.3/go.mod h1:5b+7YgP7ZICgJDBdfjZaIt+H/9L9T/YQrVfLAMboGkQ=
+github.com/go-jose/go-jose/v4 v4.0.1 h1:QVEPDE3OluqXBQZDcnNvQrInro2h0e4eqNbnZSWqS6U=
+github.com/go-jose/go-jose/v4 v4.0.1/go.mod h1:WVf9LFMHh/QVrmqrOfqun0C45tMe3RoiKJMPvgWwLfY=
 github.com/go-kit/kit v0.4.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-kit/kit v0.13.0 h1:OoneCcHKHQ03LfBpoQCUfCluwd2Vt3ohz+kvbJneZAU=
 github.com/go-kit/kit v0.13.0/go.mod h1:phqEHMMUbyrCFCTgH48JueqrM3md2HcAZ8N3XE4FKDg=
@@ -185,8 +191,6 @@ github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:W
 github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
 github.com/golang/protobuf v1.4.1/go.mod h1:U8fpvMrcmy5pZrNK1lt4xCsGvpyWQ/VVv6QDs8UjoX8=
 github.com/golang/protobuf v1.4.3/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
-github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
-github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
 github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
 github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/golang/snappy v0.0.3/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
@@ -204,14 +208,16 @@ github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMyw
 github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.3/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.7/go.mod h1:n+brtR0CgQNWTVd5ZUFpTBC8YFBDLK/h/bpaJ8/DtOE=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/go-configfs-tsm v0.2.2 h1:YnJ9rXIOj5BYD7/0DNnzs8AOp7UcvjfTvt215EWcs98=
+github.com/google/go-configfs-tsm v0.2.2/go.mod h1:EL1GTDFMb5PZQWDviGfZV9n87WeGTR/JUg13RfwkgRo=
 github.com/google/go-sev-guest v0.9.3 h1:GOJ+EipURdeWFl/YYdgcCxyPeMgQUWlI056iFkBD8UU=
+github.com/google/go-sev-guest v0.9.3/go.mod h1:hc1R4R6f8+NcJwITs0L90fYWTsBpd1Ix+Gur15sqHDs=
 github.com/google/go-tdx-guest v0.3.1 h1:gl0KvjdsD4RrJzyLefDOvFOUH3NAJri/3qvaL5m83Iw=
+github.com/google/go-tdx-guest v0.3.1/go.mod h1:/rc3d7rnPykOPuY8U9saMyEps0PZDThLk/RygXm04nE=
 github.com/google/go-tpm v0.9.0 h1:sQF6YqWMi+SCXpsmS3fd21oPy/vSddwZry4JnmltHVk=
 github.com/google/go-tpm v0.9.0/go.mod h1:FkNVkc6C+IsvDI9Jw1OveJmxGZUUaKxtrpOS47QWKfU=
 github.com/google/go-tpm-tools v0.4.4 h1:oiQfAIkc6xTy9Fl5NKTeTJkBTlXdHsxAofmQyxBKY98=
@@ -219,6 +225,7 @@ github.com/google/go-tpm-tools v0.4.4/go.mod h1:T8jXkp2s+eltnCDIsXR84/MTcVU9Ja7b
 github.com/google/go-tspi v0.3.0 h1:ADtq8RKfP+jrTyIWIZDIYcKOMecRqNJFOew2IT0Inus=
 github.com/google/go-tspi v0.3.0/go.mod h1:xfMGI3G0PhxCdNVcYr1C4C+EizojDg/TXuX5by8CiHI=
 github.com/google/logger v1.1.1 h1:+6Z2geNxc9G+4D4oDO9njjjn2d0wN5d7uOo0vOIW1NQ=
+github.com/google/logger v1.1.1/go.mod h1:BkeJZ+1FhQ+/d087r4dzojEg1u2ZX+ZqG1jTUrLM+zQ=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
 github.com/google/s2a-go v0.1.7 h1:60BLSyTrOV4/haCDW4zb1guZItoSq8foHCXrAnjBo/o=
 github.com/google/s2a-go v0.1.7/go.mod h1:50CgR4k1jNlWBu4UfS4AcfhVe1r6pdZPygJ3R8F0Qdw=
@@ -239,6 +246,7 @@ github.com/hashicorp/go-cleanhttp v0.5.2/go.mod h1:kO/YDlP8L1346E6Sodw+PrpBSV4/S
 github.com/hashicorp/go-hclog v0.9.2/go.mod h1:5CU+agLiy3J7N7QjHK5d05KxGsuXiQLrjA0H7acj2lQ=
 github.com/hashicorp/go-hclog v0.16.2/go.mod h1:whpDNt7SSdeAju8AWKIWsul05p54N/39EeqMAyrmvFQ=
 github.com/hashicorp/go-hclog v1.2.2 h1:ihRI7YFwcZdiSD7SIenIhHfQH3OuDvWerAUBZbeQS3M=
+github.com/hashicorp/go-hclog v1.2.2/go.mod h1:W4Qnvbt70Wk/zYJryRzDRU/4r0kIg0PVHBcfoyhpF5M=
 github.com/hashicorp/go-multierror v1.0.0/go.mod h1:dHtQlpGsu+cZNNAkkCN/P3hoUDHhCYQXV3UM06sGGrk=
 github.com/hashicorp/go-multierror v1.1.1 h1:H5DkEtf6CXdFp0N0Em5UCwQpXMWke8IA0+lD48awMYo=
 github.com/hashicorp/go-multierror v1.1.1/go.mod h1:iw975J/qwKPdAO1clOe2L8331t/9/fmwbPZ6JB6eMoM=
@@ -256,8 +264,8 @@ github.com/hashicorp/go-sockaddr v1.0.2/go.mod h1:rB4wwRAUzs07qva3c5SdrY/NEtAUjG
 github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/hashicorp/vault/api v1.12.0/go.mod h1:si+lJCYO7oGkIoNPAN8j3azBLTn9SjMGS+jFaHd1Cck=
-github.com/hashicorp/vault/api v1.12.2 h1:7YkCTE5Ni90TcmYHDBExdt4WGJxhpzaHqR6uGbQb/rE=
-github.com/hashicorp/vault/api v1.12.2/go.mod h1:LSGf1NGT1BnvFFnKVtnvcaLBM2Lz+gJdpL6HUYed8KE=
+github.com/hashicorp/vault/api v1.13.0 h1:RTCGpE2Rgkn9jyPcFlc7YmNocomda44k5ck8FKMH41Y=
+github.com/hashicorp/vault/api v1.13.0/go.mod h1:0cb/uZUv1w2cVu9DIvuW1SMlXXC6qtATJt+LXJRx+kg=
 github.com/hashicorp/vault/api/auth/approle v0.6.0 h1:ELfFFQlTM/e97WJKu1HvNFa7lQ3tlTwwzrR1NJE1V7Y=
 github.com/hashicorp/vault/api/auth/approle v0.6.0/go.mod h1:CCoIl1xBC3lAWpd1HV+0ovk76Z8b8Mdepyk21h3pGk0=
 github.com/hashicorp/vault/api/auth/kubernetes v0.6.0 h1:K8sKGhtTAqGKfzaaYvUSIOAqTOIn3Gk1EsCEAMzZHtM=
@@ -324,10 +332,12 @@ github.com/konsorten/go-windows-terminal-sequences v1.0.2/go.mod h1:T0+1ngSBFLxv
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.2.0/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/pty v1.1.8/go.mod h1:O1sed60cT9XZ5uDucP5qwvh+TE3NnUj51EiZO/lmSfw=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/lib/pq v1.0.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
@@ -335,6 +345,7 @@ github.com/lib/pq v1.1.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/lib/pq v1.2.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/lib/pq v1.10.2/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
+github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/manifoldco/promptui v0.9.0 h1:3V4HzJk1TtXW1MTZMP7mdlwbBpIinw3HztaIlYthEiA=
 github.com/manifoldco/promptui v0.9.0/go.mod h1:ka04sppxSGFAtxX0qhlYQjISsg9mR4GWtQEhdbn6Pgg=
@@ -375,6 +386,7 @@ github.com/mitchellh/reflectwalk v1.0.2/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx
 github.com/newrelic/go-agent/v3 v3.32.0 h1:99Et9lXXzeQV1CfYldfeTXv+d9W9KatpMbb50kIscWo=
 github.com/newrelic/go-agent/v3 v3.32.0/go.mod h1:SMdqPzE/ghkWdY0rYGSD7Clw2daK/XH6pUnVd4albg4=
 github.com/pborman/uuid v1.2.1 h1:+ZZIw58t/ozdjRaXh/3awHfmWRbzYxJoAdNJxe/3pvw=
+github.com/pborman/uuid v1.2.1/go.mod h1:X/NO0urCmaxf9VXbdlT7C2Yzkj2IKimNn4k+gtPdI/k=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/peterbourgon/diskv/v3 v3.0.1 h1:x06SQA46+PKIUftmEujdwSEpIx8kR+M9eLYsUxeYveU=
 github.com/peterbourgon/diskv/v3 v3.0.1/go.mod h1:kJ5Ny7vLdARGU3WUuy6uzO6T0nb/2gWcT1JiBvRmb5o=
@@ -397,6 +409,7 @@ github.com/prometheus/procfs v0.12.0 h1:jluTpSng7V9hY0O2R9DzzJHYb2xULk9VTR1V1R/k
 github.com/prometheus/procfs v0.12.0/go.mod h1:pcuDEFsWDnvcgNzo4EEweacyhjeA9Zk3cnaOZAZEfOo=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
+github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
 github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
 github.com/rs/xid v1.5.0 h1:mKX4bl4iPYJtEIxp6CYiUuLQ/8DYMoz0PUdtGgMFRVc=
 github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
@@ -485,6 +498,7 @@ go.opentelemetry.io/otel v1.24.0/go.mod h1:W7b9Ozg4nkF5tWI5zsXkaKKDjdVjpD4oAt9Qi
 go.opentelemetry.io/otel/metric v1.24.0 h1:6EhoGWWK28x1fbpA4tYTOWBkPefTDQnb8WSGXlc88kI=
 go.opentelemetry.io/otel/metric v1.24.0/go.mod h1:VYhLe1rFfxuTXLgj4CBiyz+9WYBA8pNGJgDcSFRKBco=
 go.opentelemetry.io/otel/sdk v1.22.0 h1:6coWHw9xw7EfClIC/+O31R8IY3/+EiRFHevmHafB2Gw=
+go.opentelemetry.io/otel/sdk v1.22.0/go.mod h1:iu7luyVGYovrRpe2fmj3CVKouQNdTOkxtLzPvPz1DOc=
 go.opentelemetry.io/otel/trace v1.24.0 h1:CsKnnL4dUAr/0llH9FKuc698G04IrpWV0MQA/Y1YELI=
 go.opentelemetry.io/otel/trace v1.24.0/go.mod h1:HPc3Xr/cOApsBI154IU0OI0HJexz+aw5uPdbs3UCjNU=
 go.step.sm/cli-utils v0.9.0 h1:55jYcsQbnArNqepZyAwcato6Zy2MoZDRkWW+jF+aPfQ=
@@ -501,6 +515,7 @@ go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/
 go.uber.org/multierr v1.3.0/go.mod h1:VgVr7evmIr6uPjLBxg28wmKNXyqE9akIJ5XnfpiKl+4=
 go.uber.org/multierr v1.5.0/go.mod h1:FeouvMocqHpRaaGuG9EjoKcStLC43Zu/fmqdUMPcKYU=
 go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
+go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
 go.uber.org/tools v0.0.0-20190618225709-2cfd321de3ee/go.mod h1:vJERXedbb3MVM5f9Ejo0C68/HhF8uaILCdgjnY+goOA=
 go.uber.org/zap v1.9.1/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
 go.uber.org/zap v1.10.0/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
@@ -553,8 +568,8 @@ golang.org/x/net v0.17.0/go.mod h1:NxSsAGuq816PNPmqtQdLE42eU2Fs7NoRIZrHJAlaCOE=
 golang.org/x/net v0.24.0 h1:1PcaxkF854Fu3+lvBIx5SYn9wRlBzzcnHZSiaFFAb0w=
 golang.org/x/net v0.24.0/go.mod h1:2Q7sJY5mzlzWjKtYUEXSlBWCdyaioyXzRB2RtU8KVE8=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
-golang.org/x/oauth2 v0.18.0 h1:09qnuIAgzdx1XplqJvW6CQqMCtGZykZWcXzPMPUusvI=
-golang.org/x/oauth2 v0.18.0/go.mod h1:Wf7knwG0MPoWIMMBgFlEaSUDaKskp0dCfrlJRJXbBi8=
+golang.org/x/oauth2 v0.19.0 h1:9+E/EZBCbTLNrbN35fHv/a/d/mOBatymz1zbtQrXpIg=
+golang.org/x/oauth2 v0.19.0/go.mod h1:vYi7skDa1x015PmRRYZ7+s1cWyPgrPiSYRe4rnsexc8=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -609,13 +624,13 @@ golang.org/x/term v0.13.0/go.mod h1:LTmsnFJwVN6bCy1rVCoS+qHT1HhALEFxKncY3WNNh4U=
 golang.org/x/term v0.15.0/go.mod h1:BDl952bC7+uMoWR75FIrCDx79TPU9oHkTZ9yRbYOrX0=
 golang.org/x/term v0.17.0/go.mod h1:lLRBjIVuehSbZlaOtGMbcMncT+aqLLLmKrsjNrUguwk=
 golang.org/x/term v0.19.0 h1:+ThwsDv+tYfnJFhF4L8jITxu1tdTWRTZpdsWgEgjL6Q=
+golang.org/x/term v0.19.0/go.mod h1:2CuTdWZ7KHSQwUzKva0cbMg6q2DMI3Mmxp+gKJbskEk=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.4/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
 golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
@@ -646,12 +661,10 @@ golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-google.golang.org/api v0.172.0 h1:/1OcMZGPmW1rX2LCu2CmGUD1KXK1+pfzxotxyRUCCdk=
-google.golang.org/api v0.172.0/go.mod h1:+fJZq6QXWfa9pXhnIzsjx4yI22d4aI9ZpLb58gvXjis=
+google.golang.org/api v0.176.0 h1:dHj1/yv5Dm/eQTXiP9hNCRT3xzJHWXeNdRq29XbMxoE=
+google.golang.org/api v0.176.0/go.mod h1:Rra+ltKu14pps/4xTycZfobMgLpbosoaaL7c+SEMrO8=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
-google.golang.org/appengine v1.6.8 h1:IhEN5q69dyKagZPYMSdIjS2HqprW324FRQZJcGqPAsM=
-google.golang.org/appengine v1.6.8/go.mod h1:1jJ3jBArFh5pcgW8gCtRJnepW8FzD1V44FJffLiz/Ds=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98Agz4BDEuKkezgsaosCRResVns1a3J2ZsMNc=
 google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013/go.mod h1:NbSheEEYHJ7i3ixzK3sjbqSGDJWnxyFXZblF3eUsNvo=
@@ -659,8 +672,8 @@ google.golang.org/genproto v0.0.0-20240227224415-6ceb2ff114de h1:F6qOa9AZTYJXOUE
 google.golang.org/genproto v0.0.0-20240227224415-6ceb2ff114de/go.mod h1:VUhTRKeHn9wwcdrk73nvdC9gF178Tzhmt/qyaFcPLSo=
 google.golang.org/genproto/googleapis/api v0.0.0-20240401170217-c3f982113cda h1:b6F6WIV4xHHD0FA4oIyzU6mHWg2WI2X1RBehwa5QN38=
 google.golang.org/genproto/googleapis/api v0.0.0-20240401170217-c3f982113cda/go.mod h1:AHcE/gZH76Bk/ROZhQphlRoWo5xKDEtz3eVEO1LfA8c=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240325203815-454cdb8f5daa h1:RBgMaUMP+6soRkik4VoN8ojR2nex2TqZwjSSogic+eo=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240325203815-454cdb8f5daa/go.mod h1:WtryC6hu0hhx87FDGxWCDptyssuo68sk10vYjF+T9fY=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240415180920-8c6c420018be h1:LG9vZxsWGOmUKieR8wPAUR3u3MpnYFQZROPIMaXh7/A=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240415180920-8c6c420018be/go.mod h1:WtryC6hu0hhx87FDGxWCDptyssuo68sk10vYjF+T9fY=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
 google.golang.org/grpc v1.25.1/go.mod h1:c3i+UQWmh7LiEpx4sFZnkU36qjEYZ0imhYfXVyQciAY=
@@ -677,14 +690,13 @@ google.golang.org/protobuf v1.22.0/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2
 google.golang.org/protobuf v1.23.0/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2l/sGQquU=
 google.golang.org/protobuf v1.23.1-0.20200526195155-81db48ad09cc/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2l/sGQquU=
 google.golang.org/protobuf v1.25.0/go.mod h1:9JNX74DMeImyA3h4bdi1ymwjUzf21/xIlbajtzgsN7c=
-google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
-google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
 google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 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 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+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/inconshreveable/log15.v2 v2.0.0-20180818164646-67afb5ed74ec/go.mod h1:aPpfJ7XW+gOuirDoZ8gHhLh3kZ1B08FtV2bbmy7Jv3s=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

scep/options.go

@@ -37,19 +37,21 @@ func (o *Options) Validate() error {
 	switch {
 	case len(o.Intermediates) == 0:
 		return errors.New("no intermediate certificate available for SCEP authority")
-	case o.Signer == nil:
-		return errors.New("no signer available for SCEP authority")
 	case o.SignerCert == nil:
 		return errors.New("no signer certificate available for SCEP authority")
 	}
 
-	// check if the signer (intermediate CA) certificate has the same public key as
-	// the signer. According to the RFC it seems valid to have different keys for
-	// the intermediate and the CA signing new certificates, so this might change
-	// in the future.
-	signerPublicKey := o.Signer.Public().(comparablePublicKey)
-	if !signerPublicKey.Equal(o.SignerCert.PublicKey) {
-		return errors.New("mismatch between signer certificate and public key")
+	// the signer is optional, but if it's set, its public key must match the signer
+	// certificate public key.
+	if o.Signer != nil {
+		// check if the signer (intermediate CA) certificate has the same public key as
+		// the signer. According to the RFC it seems valid to have different keys for
+		// the intermediate and the CA signing new certificates, so this might change
+		// in the future.
+		signerPublicKey := o.Signer.Public().(comparablePublicKey)
+		if !signerPublicKey.Equal(o.SignerCert.PublicKey) {
+			return errors.New("mismatch between signer certificate and public key")
+		}
 	}
 
 	// decrypter can be nil in case a signing only key is used; validation complete.

test/integration/scep/common_test.go

@@ -0,0 +1,273 @@
+package sceptest
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"io"
+	"math/big"
+	"net"
+	"net/http"
+	"net/url"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/smallstep/pkcs7"
+	"github.com/smallstep/scep"
+	"go.step.sm/crypto/minica"
+	"go.step.sm/crypto/x509util"
+
+	"github.com/smallstep/certificates/ca"
+	"github.com/smallstep/certificates/cas/apiv1"
+)
+
+func newCAClient(t *testing.T, caURL, rootFilepath string) *ca.Client {
+	caClient, err := ca.NewClient(
+		caURL,
+		ca.WithRootFile(rootFilepath),
+	)
+	require.NoError(t, err)
+	return caClient
+}
+
+func requireHealthyCA(t *testing.T, caClient *ca.Client) {
+	ctx := context.Background()
+	healthResponse, err := caClient.HealthWithContext(ctx)
+	require.NoError(t, err)
+	if assert.NotNil(t, healthResponse) {
+		require.Equal(t, "ok", healthResponse.Status)
+	}
+}
+
+// reservePort "reserves" a TCP port by opening a listener on a random
+// port and immediately closing it. The port can then be assumed to be
+// available for running a server on.
+func reservePort(t *testing.T) (host, port string) {
+	t.Helper()
+	l, err := net.Listen("tcp", ":0")
+	require.NoError(t, err)
+
+	address := l.Addr().String()
+	err = l.Close()
+	require.NoError(t, err)
+
+	host, port, err = net.SplitHostPort(address)
+	require.NoError(t, err)
+
+	return
+}
+
+type client struct {
+	caURL      string
+	caCert     *x509.Certificate
+	httpClient *http.Client
+}
+
+func createSCEPClient(t *testing.T, caURL string, root *x509.Certificate) *client {
+	t.Helper()
+	trustedRoots := x509.NewCertPool()
+	trustedRoots.AddCert(root)
+	transport := http.DefaultTransport.(*http.Transport).Clone()
+	transport.TLSClientConfig = &tls.Config{
+		RootCAs: trustedRoots,
+	}
+	httpClient := &http.Client{
+		Transport: transport,
+	}
+	return &client{
+		caURL:      caURL,
+		httpClient: httpClient,
+	}
+}
+
+func (c *client) getCACert(t *testing.T) error {
+	// return early if CA certificate already available
+	if c.caCert != nil {
+		return nil
+	}
+
+	resp, err := c.httpClient.Get(fmt.Sprintf("%s?operation=GetCACert&message=test", c.caURL))
+	if err != nil {
+		return fmt.Errorf("failed get request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return fmt.Errorf("failed reading response body: %w", err)
+	}
+
+	t.Log(string(body))
+
+	// SCEP CA/RA certificate selection. If there's only a single certificate, it will
+	// be used as the CA certificate at all times. If there's multiple, the first certificate
+	// is assumed to be the certificate of the recipient to encrypt messages to.
+	switch ct := resp.Header.Get("Content-Type"); ct {
+	case "application/x-x509-ca-cert":
+		cert, err := x509.ParseCertificate(body)
+		if err != nil {
+			return fmt.Errorf("failed parsing response body: %w", err)
+		}
+		if _, ok := cert.PublicKey.(*rsa.PublicKey); !ok {
+			return fmt.Errorf("certificate has unexpected public key type %T", cert.PublicKey)
+		}
+		c.caCert = cert
+	case "application/x-x509-ca-ra-cert":
+		certs, err := scep.CACerts(body)
+		if err != nil {
+			return fmt.Errorf("failed parsing response body: %w", err)
+		}
+		cert := certs[0]
+		if _, ok := cert.PublicKey.(*rsa.PublicKey); !ok {
+			return fmt.Errorf("certificate has unexpected public key type %T", cert.PublicKey)
+		}
+		c.caCert = cert
+	default:
+		return fmt.Errorf("unexpected content-type value %q", ct)
+	}
+
+	return nil
+}
+
+func (c *client) requestCertificate(t *testing.T, commonName string, sans []string) (*x509.Certificate, error) {
+	if err := c.getCACert(t); err != nil {
+		return nil, fmt.Errorf("failed getting CA certificate: %w", err)
+	}
+
+	signer, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		return nil, fmt.Errorf("failed creating SCEP private key: %w", err)
+	}
+
+	csr, err := x509util.CreateCertificateRequest(commonName, sans, signer)
+	if err != nil {
+		return nil, fmt.Errorf("failed creating CSR: %w", err)
+	}
+
+	tmpl := &x509.Certificate{
+		Subject:        csr.Subject,
+		PublicKey:      signer.Public(),
+		SerialNumber:   big.NewInt(1),
+		NotBefore:      time.Now().Add(-1 * time.Hour),
+		NotAfter:       time.Now().Add(1 * time.Hour),
+		DNSNames:       csr.DNSNames,
+		IPAddresses:    csr.IPAddresses,
+		EmailAddresses: csr.EmailAddresses,
+		URIs:           csr.URIs,
+	}
+
+	selfSigned, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, signer.Public(), signer)
+	if err != nil {
+		return nil, fmt.Errorf("failed creating self signed certificate: %w", err)
+	}
+	selfSignedCertificate, err := x509.ParseCertificate(selfSigned)
+	if err != nil {
+		return nil, fmt.Errorf("failed parsing self signed certificate: %w", err)
+	}
+
+	msgTmpl := &scep.PKIMessage{
+		TransactionID: "test-1",
+		MessageType:   scep.PKCSReq,
+		SenderNonce:   []byte("test-nonce-1"),
+		Recipients:    []*x509.Certificate{c.caCert},
+		SignerCert:    selfSignedCertificate,
+		SignerKey:     signer,
+	}
+
+	msg, err := scep.NewCSRRequest(csr, msgTmpl)
+	if err != nil {
+		return nil, fmt.Errorf("failed creating SCEP PKCSReq message: %w", err)
+	}
+
+	t.Log(string(msg.Raw))
+
+	u, err := url.Parse(c.caURL)
+	if err != nil {
+		return nil, fmt.Errorf("failed parsing CA URL: %w", err)
+	}
+
+	opURL := u.ResolveReference(&url.URL{RawQuery: fmt.Sprintf("operation=PKIOperation&message=%s", url.QueryEscape(base64.StdEncoding.EncodeToString(msg.Raw)))})
+	resp, err := c.httpClient.Get(opURL.String())
+	if err != nil {
+		return nil, fmt.Errorf("failed get request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if ct := resp.Header.Get("Content-Type"); ct != "application/x-pki-message" {
+		return nil, fmt.Errorf("received unexpected content type %q", ct)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed reading response body: %w", err)
+	}
+
+	t.Log(string(body))
+
+	signedData, err := pkcs7.Parse(body)
+	if err != nil {
+		return nil, fmt.Errorf("failed parsing response body: %w", err)
+	}
+
+	// TODO: verify the signature?
+
+	p7, err := pkcs7.Parse(signedData.Content)
+	if err != nil {
+		return nil, fmt.Errorf("failed decrypting inner p7: %w", err)
+	}
+
+	content, err := p7.Decrypt(selfSignedCertificate, signer)
+	if err != nil {
+		return nil, fmt.Errorf("failed decrypting response: %w", err)
+	}
+
+	p7, err = pkcs7.Parse(content)
+	if err != nil {
+		return nil, fmt.Errorf("failed parsing p7 content: %w", err)
+	}
+
+	cert := p7.Certificates[0]
+
+	return cert, nil
+}
+
+type testCAS struct {
+	ca *minica.CA
+}
+
+func (c *testCAS) CreateCertificate(req *apiv1.CreateCertificateRequest) (*apiv1.CreateCertificateResponse, error) {
+	cert, err := c.ca.SignCSR(req.CSR)
+	if err != nil {
+		return nil, fmt.Errorf("failed signing CSR: %w", err)
+	}
+
+	return &apiv1.CreateCertificateResponse{
+		Certificate:      cert,
+		CertificateChain: []*x509.Certificate{cert, c.ca.Intermediate},
+	}, nil
+}
+func (c *testCAS) RenewCertificate(req *apiv1.RenewCertificateRequest) (*apiv1.RenewCertificateResponse, error) {
+	return nil, errors.New("not implemented")
+}
+
+func (c *testCAS) RevokeCertificate(req *apiv1.RevokeCertificateRequest) (*apiv1.RevokeCertificateResponse, error) {
+	return nil, errors.New("not implemented")
+}
+
+func (c *testCAS) GetCertificateAuthority(req *apiv1.GetCertificateAuthorityRequest) (*apiv1.GetCertificateAuthorityResponse, error) {
+	return &apiv1.GetCertificateAuthorityResponse{
+		RootCertificate:          c.ca.Root,
+		IntermediateCertificates: []*x509.Certificate{c.ca.Intermediate},
+	}, nil
+}
+
+var _ apiv1.CertificateAuthorityService = (*testCAS)(nil)
+var _ apiv1.CertificateAuthorityGetter = (*testCAS)(nil)

test/integration/scep/decrypter_cas_test.go

@@ -0,0 +1,149 @@
+package sceptest
+
+import (
+	"context"
+	"crypto"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/json"
+	"encoding/pem"
+	"fmt"
+	"math/big"
+	"net"
+	"net/http"
+	"path/filepath"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"go.step.sm/crypto/keyutil"
+	"go.step.sm/crypto/minica"
+	"go.step.sm/crypto/pemutil"
+
+	"github.com/smallstep/certificates/authority/config"
+	"github.com/smallstep/certificates/authority/provisioner"
+	"github.com/smallstep/certificates/ca"
+	"github.com/smallstep/certificates/cas/apiv1"
+)
+
+func TestIssuesCertificateUsingSCEPWithDecrypterAndUpstreamCAS(t *testing.T) {
+	signer, err := keyutil.GenerateSigner("EC", "P-256", 0)
+	require.NoError(t, err)
+
+	dir := t.TempDir()
+	m, err := minica.New(minica.WithName("Step E2E | SCEP Decrypter w/ Upstream CAS"), minica.WithGetSignerFunc(func() (crypto.Signer, error) {
+		return signer, nil
+	}))
+	require.NoError(t, err)
+
+	rootFilepath := filepath.Join(dir, "root.crt")
+	_, err = pemutil.Serialize(m.Root, pemutil.WithFilename(rootFilepath))
+	require.NoError(t, err)
+
+	intermediateCertFilepath := filepath.Join(dir, "intermediate.crt")
+	_, err = pemutil.Serialize(m.Intermediate, pemutil.WithFilename(intermediateCertFilepath))
+	require.NoError(t, err)
+
+	intermediateKeyFilepath := filepath.Join(dir, "intermediate.key")
+	_, err = pemutil.Serialize(m.Signer, pemutil.WithFilename(intermediateKeyFilepath))
+	require.NoError(t, err)
+
+	decrypterKey, err := keyutil.GenerateKey("RSA", "", 2048)
+	require.NoError(t, err)
+
+	decrypter, ok := decrypterKey.(crypto.Decrypter)
+	require.True(t, ok)
+
+	decrypterCertifiate, err := m.Sign(&x509.Certificate{
+		Subject:      pkix.Name{CommonName: "decrypter"},
+		PublicKey:    decrypter.Public(),
+		SerialNumber: big.NewInt(1),
+		NotBefore:    time.Now().Add(-1 * time.Hour),
+		NotAfter:     time.Now().Add(1 * time.Hour),
+		DNSNames:     []string{"decrypter"},
+	})
+	require.NoError(t, err)
+
+	b, err := pemutil.Serialize(decrypterCertifiate)
+	require.NoError(t, err)
+	decrypterCertificatePEMBytes := pem.EncodeToMemory(b)
+
+	b, err = pemutil.Serialize(decrypter, pemutil.WithPassword([]byte("1234")))
+	require.NoError(t, err)
+	decrypterKeyPEMBytes := pem.EncodeToMemory(b)
+
+	// get a random address to listen on and connect to; currently no nicer way to get one before starting the server
+	// TODO(hs): find/implement a nicer way to expose the CA URL, similar to how e.g. httptest.Server exposes it?
+	host, port := reservePort(t)
+
+	prov := &provisioner.SCEP{
+		ID:                            "scep",
+		Name:                          "scep",
+		Type:                          "SCEP",
+		ForceCN:                       false,
+		ChallengePassword:             "",
+		EncryptionAlgorithmIdentifier: 2,
+		MinimumPublicKeyLength:        2048,
+		Claims:                        &config.GlobalProvisionerClaims,
+		DecrypterCertificate:          decrypterCertificatePEMBytes,
+		DecrypterKeyPEM:               decrypterKeyPEMBytes,
+		DecrypterKeyPassword:          "1234",
+	}
+
+	err = prov.Init(provisioner.Config{})
+	require.NoError(t, err)
+
+	apiv1.Register("test-scep-cas", func(_ context.Context, opts apiv1.Options) (apiv1.CertificateAuthorityService, error) {
+		return &testCAS{
+			ca: m,
+		}, nil
+	})
+
+	cfg := &config.Config{
+		Address:  net.JoinHostPort(host, port), // reuse the address that was just "reserved"
+		DNSNames: []string{"127.0.0.1", "[::1]", "localhost"},
+		AuthorityConfig: &config.AuthConfig{
+			Options: &apiv1.Options{
+				AuthorityID:          "stepca-test-scep",
+				Type:                 "test-scep-cas",
+				CertificateAuthority: "test-cas",
+			},
+			AuthorityID:    "stepca-test-scep",
+			DeploymentType: "standalone-test",
+			Provisioners:   provisioner.List{prov},
+		},
+		Logger: json.RawMessage(`{"format": "text"}`),
+	}
+	c, err := ca.New(cfg)
+	require.NoError(t, err)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	go func() {
+		defer wg.Done()
+		err = c.Run()
+		require.ErrorIs(t, err, http.ErrServerClosed)
+	}()
+
+	// instantiate a client for the CA running at the random address
+	caClient := newCAClient(t, fmt.Sprintf("https://localhost:%s", port), rootFilepath)
+	requireHealthyCA(t, caClient)
+
+	scepClient := createSCEPClient(t, fmt.Sprintf("https://localhost:%s/scep/scep", port), m.Root)
+	cert, err := scepClient.requestCertificate(t, "test.localhost", []string{"test.localhost"})
+	assert.NoError(t, err)
+	require.NotNil(t, cert)
+
+	assert.Equal(t, "test.localhost", cert.Subject.CommonName)
+	assert.Equal(t, "Step E2E | SCEP Decrypter w/ Upstream CAS Intermediate CA", cert.Issuer.CommonName)
+
+	// done testing; stop and wait for the server to quit
+	err = c.Stop()
+	require.NoError(t, err)
+
+	wg.Wait()
+}

test/integration/scep/decrypter_test.go

@@ -0,0 +1,139 @@
+package sceptest
+
+import (
+	"crypto"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/json"
+	"encoding/pem"
+	"fmt"
+	"math/big"
+	"net"
+	"net/http"
+	"path/filepath"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"go.step.sm/crypto/keyutil"
+	"go.step.sm/crypto/minica"
+	"go.step.sm/crypto/pemutil"
+
+	"github.com/smallstep/certificates/authority/config"
+	"github.com/smallstep/certificates/authority/provisioner"
+	"github.com/smallstep/certificates/ca"
+)
+
+func TestIssuesCertificateUsingSCEPWithDecrypter(t *testing.T) {
+	signer, err := keyutil.GenerateSigner("EC", "P-256", 0)
+	require.NoError(t, err)
+
+	dir := t.TempDir()
+	m, err := minica.New(minica.WithName("Step E2E | SCEP Decrypter"), minica.WithGetSignerFunc(func() (crypto.Signer, error) {
+		return signer, nil
+	}))
+	require.NoError(t, err)
+
+	rootFilepath := filepath.Join(dir, "root.crt")
+	_, err = pemutil.Serialize(m.Root, pemutil.WithFilename(rootFilepath))
+	require.NoError(t, err)
+
+	intermediateCertFilepath := filepath.Join(dir, "intermediate.crt")
+	_, err = pemutil.Serialize(m.Intermediate, pemutil.WithFilename(intermediateCertFilepath))
+	require.NoError(t, err)
+
+	intermediateKeyFilepath := filepath.Join(dir, "intermediate.key")
+	_, err = pemutil.Serialize(m.Signer, pemutil.WithFilename(intermediateKeyFilepath))
+	require.NoError(t, err)
+
+	decrypterKey, err := keyutil.GenerateKey("RSA", "", 2048)
+	require.NoError(t, err)
+
+	decrypter, ok := decrypterKey.(crypto.Decrypter)
+	require.True(t, ok)
+
+	decrypterCertifiate, err := m.Sign(&x509.Certificate{
+		Subject:      pkix.Name{CommonName: "decrypter"},
+		PublicKey:    decrypter.Public(),
+		SerialNumber: big.NewInt(1),
+		NotBefore:    time.Now().Add(-1 * time.Hour),
+		NotAfter:     time.Now().Add(1 * time.Hour),
+		DNSNames:     []string{"decrypter"},
+	})
+	require.NoError(t, err)
+
+	b, err := pemutil.Serialize(decrypterCertifiate)
+	require.NoError(t, err)
+	decrypterCertificatePEMBytes := pem.EncodeToMemory(b)
+
+	b, err = pemutil.Serialize(decrypter, pemutil.WithPassword([]byte("1234")))
+	require.NoError(t, err)
+	decrypterKeyPEMBytes := pem.EncodeToMemory(b)
+
+	// get a random address to listen on and connect to; currently no nicer way to get one before starting the server
+	// TODO(hs): find/implement a nicer way to expose the CA URL, similar to how e.g. httptest.Server exposes it?
+	host, port := reservePort(t)
+
+	prov := &provisioner.SCEP{
+		ID:                            "scep",
+		Name:                          "scep",
+		Type:                          "SCEP",
+		ForceCN:                       false,
+		ChallengePassword:             "",
+		EncryptionAlgorithmIdentifier: 2,
+		MinimumPublicKeyLength:        2048,
+		Claims:                        &config.GlobalProvisionerClaims,
+		DecrypterCertificate:          decrypterCertificatePEMBytes,
+		DecrypterKeyPEM:               decrypterKeyPEMBytes,
+		DecrypterKeyPassword:          "1234",
+	}
+
+	err = prov.Init(provisioner.Config{})
+	require.NoError(t, err)
+
+	cfg := &config.Config{
+		Root:             []string{rootFilepath},
+		IntermediateCert: intermediateCertFilepath,
+		IntermediateKey:  intermediateKeyFilepath,
+		Address:          net.JoinHostPort(host, port), // reuse the address that was just "reserved"
+		DNSNames:         []string{"127.0.0.1", "[::1]", "localhost"},
+		AuthorityConfig: &config.AuthConfig{
+			AuthorityID:    "stepca-test-scep",
+			DeploymentType: "standalone-test",
+			Provisioners:   provisioner.List{prov},
+		},
+		Logger: json.RawMessage(`{"format": "text"}`),
+	}
+	c, err := ca.New(cfg)
+	require.NoError(t, err)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	go func() {
+		defer wg.Done()
+		err = c.Run()
+		require.ErrorIs(t, err, http.ErrServerClosed)
+	}()
+
+	// instantiate a client for the CA running at the random address
+	caClient := newCAClient(t, fmt.Sprintf("https://localhost:%s", port), rootFilepath)
+	requireHealthyCA(t, caClient)
+
+	scepClient := createSCEPClient(t, fmt.Sprintf("https://localhost:%s/scep/scep", port), m.Root)
+	cert, err := scepClient.requestCertificate(t, "test.localhost", []string{"test.localhost"})
+	assert.NoError(t, err)
+	require.NotNil(t, cert)
+
+	assert.Equal(t, "test.localhost", cert.Subject.CommonName)
+	assert.Equal(t, "Step E2E | SCEP Decrypter Intermediate CA", cert.Issuer.CommonName)
+
+	// done testing; stop and wait for the server to quit
+	err = c.Stop()
+	require.NoError(t, err)
+
+	wg.Wait()
+}

test/integration/scep/regular_cas_test.go

@@ -0,0 +1,116 @@
+package sceptest
+
+import (
+	"context"
+	"crypto"
+	"encoding/json"
+	"fmt"
+	"net"
+	"net/http"
+	"path/filepath"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"go.step.sm/crypto/keyutil"
+	"go.step.sm/crypto/minica"
+	"go.step.sm/crypto/pemutil"
+
+	"github.com/smallstep/certificates/authority/config"
+	"github.com/smallstep/certificates/authority/provisioner"
+	"github.com/smallstep/certificates/ca"
+	"github.com/smallstep/certificates/cas/apiv1"
+)
+
+func TestFailsIssuingCertificateUsingRegularSCEPWithUpstreamCAS(t *testing.T) {
+	signer, err := keyutil.GenerateSigner("RSA", "", 2048)
+	require.NoError(t, err)
+
+	dir := t.TempDir()
+	m, err := minica.New(minica.WithName("Step E2E | SCEP Regular w/ Upstream CAS"), minica.WithGetSignerFunc(func() (crypto.Signer, error) {
+		return signer, nil
+	}))
+	require.NoError(t, err)
+
+	rootFilepath := filepath.Join(dir, "root.crt")
+	_, err = pemutil.Serialize(m.Root, pemutil.WithFilename(rootFilepath))
+	require.NoError(t, err)
+
+	intermediateCertFilepath := filepath.Join(dir, "intermediate.crt")
+	_, err = pemutil.Serialize(m.Intermediate, pemutil.WithFilename(intermediateCertFilepath))
+	require.NoError(t, err)
+
+	intermediateKeyFilepath := filepath.Join(dir, "intermediate.key")
+	_, err = pemutil.Serialize(m.Signer, pemutil.WithFilename(intermediateKeyFilepath))
+	require.NoError(t, err)
+
+	// get a random address to listen on and connect to; currently no nicer way to get one before starting the server
+	// TODO(hs): find/implement a nicer way to expose the CA URL, similar to how e.g. httptest.Server exposes it?
+	host, port := reservePort(t)
+
+	prov := &provisioner.SCEP{
+		ID:                            "scep",
+		Name:                          "scep",
+		Type:                          "SCEP",
+		ForceCN:                       false,
+		ChallengePassword:             "",
+		EncryptionAlgorithmIdentifier: 2,
+		MinimumPublicKeyLength:        2048,
+		Claims:                        &config.GlobalProvisionerClaims,
+	}
+
+	err = prov.Init(provisioner.Config{})
+	require.NoError(t, err)
+
+	apiv1.Register("test-scep-cas", func(_ context.Context, opts apiv1.Options) (apiv1.CertificateAuthorityService, error) {
+		return &testCAS{
+			ca: m,
+		}, nil
+	})
+
+	cfg := &config.Config{
+		Address:  net.JoinHostPort(host, port), // reuse the address that was just "reserved"
+		DNSNames: []string{"127.0.0.1", "[::1]", "localhost"},
+		AuthorityConfig: &config.AuthConfig{
+			Options: &apiv1.Options{
+				AuthorityID:          "stepca-test-scep",
+				Type:                 "test-scep-cas",
+				CertificateAuthority: "test-cas",
+			},
+			AuthorityID:    "stepca-test-scep",
+			DeploymentType: "standalone-test",
+			Provisioners:   provisioner.List{prov},
+		},
+		Logger: json.RawMessage(`{"format": "text"}`),
+	}
+	c, err := ca.New(cfg)
+	require.NoError(t, err)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	go func() {
+		defer wg.Done()
+		err = c.Run()
+		require.ErrorIs(t, err, http.ErrServerClosed)
+	}()
+
+	// instantiate a client for the CA running at the random address
+	caClient := newCAClient(t, fmt.Sprintf("https://localhost:%s", port), rootFilepath)
+	requireHealthyCA(t, caClient)
+
+	// issuance is expected to fail when an upstream CAS is configured, as the current
+	// CAS interfaces do not support providing a decrypter.
+	scepClient := createSCEPClient(t, fmt.Sprintf("https://localhost:%s/scep/scep", port), m.Root)
+	cert, err := scepClient.requestCertificate(t, "test.localhost", []string{"test.localhost"})
+	assert.Error(t, err)
+	assert.Nil(t, cert)
+
+	// done testing; stop and wait for the server to quit
+	err = c.Stop()
+	require.NoError(t, err)
+
+	wg.Wait()
+}

test/integration/scep/regular_test.go

@@ -0,0 +1,107 @@
+package sceptest
+
+import (
+	"crypto"
+	"encoding/json"
+	"fmt"
+	"net"
+	"net/http"
+	"path/filepath"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"go.step.sm/crypto/keyutil"
+	"go.step.sm/crypto/minica"
+	"go.step.sm/crypto/pemutil"
+
+	"github.com/smallstep/certificates/authority/config"
+	"github.com/smallstep/certificates/authority/provisioner"
+	"github.com/smallstep/certificates/ca"
+)
+
+func TestIssuesCertificateUsingRegularSCEPConfiguration(t *testing.T) {
+	signer, err := keyutil.GenerateSigner("RSA", "", 2048)
+	require.NoError(t, err)
+
+	dir := t.TempDir()
+	m, err := minica.New(minica.WithName("Step E2E | SCEP Regular"), minica.WithGetSignerFunc(func() (crypto.Signer, error) {
+		return signer, nil
+	}))
+	require.NoError(t, err)
+
+	rootFilepath := filepath.Join(dir, "root.crt")
+	_, err = pemutil.Serialize(m.Root, pemutil.WithFilename(rootFilepath))
+	require.NoError(t, err)
+
+	intermediateCertFilepath := filepath.Join(dir, "intermediate.crt")
+	_, err = pemutil.Serialize(m.Intermediate, pemutil.WithFilename(intermediateCertFilepath))
+	require.NoError(t, err)
+
+	intermediateKeyFilepath := filepath.Join(dir, "intermediate.key")
+	_, err = pemutil.Serialize(m.Signer, pemutil.WithFilename(intermediateKeyFilepath))
+	require.NoError(t, err)
+
+	// get a random address to listen on and connect to; currently no nicer way to get one before starting the server
+	// TODO(hs): find/implement a nicer way to expose the CA URL, similar to how e.g. httptest.Server exposes it?
+	host, port := reservePort(t)
+
+	prov := &provisioner.SCEP{
+		ID:                            "scep",
+		Name:                          "scep",
+		Type:                          "SCEP",
+		ForceCN:                       false,
+		ChallengePassword:             "",
+		EncryptionAlgorithmIdentifier: 2,
+		MinimumPublicKeyLength:        2048,
+		Claims:                        &config.GlobalProvisionerClaims,
+	}
+
+	err = prov.Init(provisioner.Config{})
+	require.NoError(t, err)
+
+	cfg := &config.Config{
+		Root:             []string{rootFilepath},
+		IntermediateCert: intermediateCertFilepath,
+		IntermediateKey:  intermediateKeyFilepath,
+		Address:          net.JoinHostPort(host, port), // reuse the address that was just "reserved"
+		DNSNames:         []string{"127.0.0.1", "[::1]", "localhost"},
+		AuthorityConfig: &config.AuthConfig{
+			AuthorityID:    "stepca-test-scep",
+			DeploymentType: "standalone-test",
+			Provisioners:   provisioner.List{prov},
+		},
+		Logger: json.RawMessage(`{"format": "text"}`),
+	}
+	c, err := ca.New(cfg)
+	require.NoError(t, err)
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	go func() {
+		defer wg.Done()
+		err = c.Run()
+		require.ErrorIs(t, err, http.ErrServerClosed)
+	}()
+
+	// instantiate a client for the CA running at the random address
+	caClient := newCAClient(t, fmt.Sprintf("https://localhost:%s", port), rootFilepath)
+	requireHealthyCA(t, caClient)
+
+	scepClient := createSCEPClient(t, fmt.Sprintf("https://localhost:%s/scep/scep", port), m.Root)
+	cert, err := scepClient.requestCertificate(t, "test.localhost", []string{"test.localhost"})
+	assert.NoError(t, err)
+	require.NotNil(t, cert)
+
+	assert.Equal(t, "test.localhost", cert.Subject.CommonName)
+	assert.Equal(t, "Step E2E | SCEP Regular Intermediate CA", cert.Issuer.CommonName)
+
+	// done testing; stop and wait for the server to quit
+	err = c.Stop()
+	require.NoError(t, err)
+
+	wg.Wait()
+}