From 552e9d568fde9701ea1944fb01c8aadaceaa7353 Mon Sep 17 00:00:00 2001 From: Richard Barnes Date: Tue, 29 Dec 2015 10:28:12 -0500 Subject: [PATCH] ocsp: add support for OCSP response extensions Some current uses of OCSP require extensions. In particular, Certificate Transparency (RFC 6962) can use an OCSP extension to carry a Signed Certificate Timestamp. This patch adds support for OCSP extensions (in particular, singleExtensions), by adding Extensions and ExtraExtensions fields with the same semantics as in x509.Certificate. As a side-effect, trying to parse a response with a critical extension will now return an error, just like parsing a certificate. This change does not enable extensions in OCSP requests, just responses. Change-Id: I5918f26ea1bb9d1ece96e85a6bb7691c7c017467 Reviewed-on: https://go-review.googlesource.com/18202 Reviewed-by: Adam Langley --- ocsp/ocsp.go | 44 ++++++++++++++---- ocsp/ocsp_test.go | 116 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 150 insertions(+), 10 deletions(-) diff --git a/ocsp/ocsp.go b/ocsp/ocsp.go index 99120b5..61847a5 100644 --- a/ocsp/ocsp.go +++ b/ocsp/ocsp.go @@ -85,12 +85,13 @@ type responseData struct { } type singleResponse struct { - CertID certID - Good asn1.Flag `asn1:"tag:0,optional"` - Revoked revokedInfo `asn1:"tag:1,optional"` - Unknown asn1.Flag `asn1:"tag:2,optional"` - ThisUpdate time.Time `asn1:"generalized"` - NextUpdate time.Time `asn1:"generalized,explicit,tag:0,optional"` + CertID certID + Good asn1.Flag `asn1:"tag:0,optional"` + Revoked revokedInfo `asn1:"tag:1,optional"` + Unknown asn1.Flag `asn1:"tag:2,optional"` + ThisUpdate time.Time `asn1:"generalized"` + NextUpdate time.Time `asn1:"generalized,explicit,tag:0,optional"` + SingleExtensions []pkix.Extension `asn1:"explicit,tag:1,optional"` } type revokedInfo struct { @@ -257,7 +258,7 @@ const ( AACompromise = iota ) -// Request represents an OCSP request. See RFC 2560. +// Request represents an OCSP request. See RFC 6960. type Request struct { HashAlgorithm crypto.Hash IssuerNameHash []byte @@ -265,7 +266,8 @@ type Request struct { SerialNumber *big.Int } -// Response represents an OCSP response. See RFC 2560. +// Response represents an OCSP response containing a single SingleResponse. See +// RFC 6960. type Response struct { // Status is one of {Good, Revoked, Unknown, ServerFailed} Status int @@ -278,6 +280,20 @@ type Response struct { TBSResponseData []byte Signature []byte SignatureAlgorithm x509.SignatureAlgorithm + + // Extensions contains raw X.509 extensions from the singleExtensions field + // of the OCSP response. When parsing certificates, this can be used to + // extract non-critical extensions that are not parsed by this package. When + // marshaling OCSP responses, the Extensions field is ignored, see + // ExtraExtensions. + Extensions []pkix.Extension + + // ExtraExtensions contains extensions to be copied, raw, into any marshaled + // OCSP response (in the singleExtensions field). Values override any + // extensions that would otherwise be produced based on the other fields. The + // ExtraExtensions field is not populated when parsing certificates, see + // Extensions. + ExtraExtensions []pkix.Extension } // These are pre-serialized error responses for the various non-success codes @@ -405,6 +421,13 @@ func ParseResponse(bytes []byte, issuer *x509.Certificate) (*Response, error) { r := basicResp.TBSResponseData.Responses[0] + for _, ext := range r.SingleExtensions { + if ext.Critical { + return nil, ParseError("unsupported critical extension") + } + } + ret.Extensions = r.SingleExtensions + ret.SerialNumber = r.CertID.SerialNumber switch { @@ -534,8 +557,9 @@ func CreateResponse(issuer, responderCert *x509.Certificate, template Response, IssuerKeyHash: issuerKeyHash, SerialNumber: template.SerialNumber, }, - ThisUpdate: template.ThisUpdate.UTC(), - NextUpdate: template.NextUpdate.UTC(), + ThisUpdate: template.ThisUpdate.UTC(), + NextUpdate: template.NextUpdate.UTC(), + SingleExtensions: template.ExtraExtensions, } switch template.Status { diff --git a/ocsp/ocsp_test.go b/ocsp/ocsp_test.go index d55682f..5b15c9b 100644 --- a/ocsp/ocsp_test.go +++ b/ocsp/ocsp_test.go @@ -62,6 +62,30 @@ func TestOCSPDecodeWithoutCert(t *testing.T) { } } +func TestOCSPDecodeWithExtensions(t *testing.T) { + responseBytes, _ := hex.DecodeString(ocspResponseWithCriticalExtensionHex) + _, err := ParseResponse(responseBytes, nil) + if err == nil { + t.Error(err) + } + + responseBytes, _ = hex.DecodeString(ocspResponseWithExtensionHex) + response, err := ParseResponse(responseBytes, nil) + if err != nil { + t.Fatal(err) + } + + if len(response.Extensions) != 1 { + t.Errorf("len(response.Extensions): got %v, want %v", len(response.Extensions), 1) + } + + extensionBytes := response.Extensions[0].Value + expectedBytes, _ := hex.DecodeString(ocspExtensionValueHex) + if !bytes.Equal(extensionBytes, expectedBytes) { + t.Errorf("response.Extensions[0]: got %x, want %x", extensionBytes, expectedBytes) + } +} + func TestOCSPSignature(t *testing.T) { issuerCert, _ := hex.DecodeString(startComHex) issuer, err := x509.ParseCertificate(issuerCert) @@ -162,6 +186,15 @@ func TestOCSPResponse(t *testing.T) { t.Fatal(err) } + extensionBytes, _ := hex.DecodeString(ocspExtensionValueHex) + extensions := []pkix.Extension{ + pkix.Extension{ + Id: ocspExtensionOID, + Critical: false, + Value: extensionBytes, + }, + } + producedAt := time.Now().Truncate(time.Minute) thisUpdate := time.Date(2010, 7, 7, 15, 1, 5, 0, time.UTC) nextUpdate := time.Date(2010, 7, 7, 18, 35, 17, 0, time.UTC) @@ -173,6 +206,7 @@ func TestOCSPResponse(t *testing.T) { RevokedAt: thisUpdate, RevocationReason: KeyCompromise, Certificate: responder, + ExtraExtensions: extensions, } responseBytes, err := CreateResponse(issuer, responder, template, responderPrivateKey) @@ -197,6 +231,10 @@ func TestOCSPResponse(t *testing.T) { t.Errorf("resp.RevokedAt: got %d, want %d", resp.RevokedAt, template.RevokedAt) } + if !reflect.DeepEqual(resp.Extensions, template.ExtraExtensions) { + t.Errorf("resp.Extensions: got %v, want %v", resp.Extensions, template.ExtraExtensions) + } + if !resp.ProducedAt.Equal(producedAt) { t.Errorf("resp.ProducedAt: got %d, want %d", resp.ProducedAt, producedAt) } @@ -333,6 +371,84 @@ const ocspResponseWithoutCertHex = "308201d40a0100a08201cd308201c906092b06010505 "20a1a65c7f0b6427a224b3c98edd96b9b61f706099951188b0289555ad30a216fb774651" + "5a35fca2e054dfa8" +// PKIX nonce extension +var ocspExtensionOID = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 48, 1, 2} +var ocspExtensionValueHex = "0403000000" + +const ocspResponseWithCriticalExtensionHex = "308204fe0a0100a08204f7308204f306092b0601050507300101048204e4308204e03081" + + "dba003020100a11b3019311730150603550403130e4f43535020526573706f6e64657218" + + "0f32303136303130343137303130305a3081a53081a23049300906052b0e03021a050004" + + "14c0fe0278fc99188891b3f212e9c7e1b21ab7bfc004140dfc1df0a9e0f01ce7f2b21317" + + "7e6f8d157cd4f60210017f77deb3bcbb235d44ccc7dba62e72a116180f32303130303730" + + "373135303130355aa0030a0101180f32303130303730373135303130355aa011180f3230" + + "3130303730373138333531375aa1193017301506092b06010505073001020101ff040504" + + "03000000300d06092a864886f70d01010b0500038201010031c730ca60a7a0d92d8e4010" + + "911b469de95b4d27e89de6537552436237967694f76f701cf6b45c932bd308bca4a8d092" + + "5c604ba94796903091d9e6c000178e72c1f0a24a277dd262835af5d17d3f9d7869606c9f" + + "e7c8e708a41645699895beee38bfa63bb46296683761c5d1d65439b8ab868dc3017c9eeb" + + "b70b82dbf3a31c55b457d48bb9e82b335ed49f445042eaf606b06a3e0639824924c89c63" + + "eccddfe85e6694314138b2536f5e15e07085d0f6e26d4b2f8244bab0d70de07283ac6384" + + "a0501fc3dea7cf0adfd4c7f34871080900e252ddc403e3f0265f2a704af905d3727504ed" + + "28f3214a219d898a022463c78439799ca81c8cbafdbcec34ea937cd6a08202ea308202e6" + + "308202e2308201caa003020102020101300d06092a864886f70d01010b05003019311730" + + "150603550403130e4f43535020526573706f6e646572301e170d31353031333031353530" + + "33335a170d3136303133303135353033335a3019311730150603550403130e4f43535020" + + "526573706f6e64657230820122300d06092a864886f70d01010105000382010f00308201" + + "0a0282010100e8155f2d3e6f2e8d14c62a788bd462f9f844e7a6977c83ef1099f0f6616e" + + "c5265b56f356e62c5400f0b06a2e7945a82752c636df32a895152d6074df1701dc6ccfbc" + + "bec75a70bd2b55ae2be7e6cad3b5fd4cd5b7790ab401a436d3f5f346074ffde8a99d5b72" + + "3350f0a112076614b12ef79c78991b119453445acf2416ab0046b540db14c9fc0f27b898" + + "9ad0f63aa4b8aefc91aa8a72160c36307c60fec78a93d3fddf4259902aa77e7332971c7d" + + "285b6a04f648993c6922a3e9da9adf5f81508c3228791843e5d49f24db2f1290bafd97e6" + + "55b1049a199f652cd603c4fafa330c390b0da78fbbc67e8fa021cbd74eb96222b12ace31" + + "a77dcf920334dc94581b0203010001a3353033300e0603551d0f0101ff04040302078030" + + "130603551d25040c300a06082b06010505070309300c0603551d130101ff04023000300d" + + "06092a864886f70d01010b05000382010100718012761b5063e18f0dc44644d8e6ab8612" + + "31c15fd5357805425d82aec1de85bf6d3e30fce205e3e3b8b795bbe52e40a439286d2288" + + "9064f4aeeb150359b9425f1da51b3a5c939018555d13ac42c565a0603786a919328f3267" + + "09dce52c22ad958ecb7873b9771d1148b1c4be2efe80ba868919fc9f68b6090c2f33c156" + + "d67156e42766a50b5d51e79637b7e58af74c2a951b1e642fa7741fec982cc937de37eff5" + + "9e2005d5939bfc031589ca143e6e8ab83f40ee08cc20a6b4a95a318352c28d18528dcaf9" + + "66705de17afa19d6e8ae91ddf33179d16ebb6ac2c69cae8373d408ebf8c55308be6c04d9" + + "3a25439a94299a65a709756c7a3e568be049d5c38839" + +const ocspResponseWithExtensionHex = "308204fb0a0100a08204f4308204f006092b0601050507300101048204e1308204dd3081" + + "d8a003020100a11b3019311730150603550403130e4f43535020526573706f6e64657218" + + "0f32303136303130343136353930305a3081a230819f3049300906052b0e03021a050004" + + "14c0fe0278fc99188891b3f212e9c7e1b21ab7bfc004140dfc1df0a9e0f01ce7f2b21317" + + "7e6f8d157cd4f60210017f77deb3bcbb235d44ccc7dba62e72a116180f32303130303730" + + "373135303130355aa0030a0101180f32303130303730373135303130355aa011180f3230" + + "3130303730373138333531375aa1163014301206092b0601050507300102040504030000" + + "00300d06092a864886f70d01010b05000382010100c09a33e0b2324c852421bb83f85ac9" + + "9113f5426012bd2d2279a8166e9241d18a33c870894250622ffc7ed0c4601b16d624f90b" + + "779265442cdb6868cf40ab304ab4b66e7315ed02cf663b1601d1d4751772b31bc299db23" + + "9aebac78ed6797c06ed815a7a8d18d63cfbb609cafb47ec2e89e37db255216eb09307848" + + "d01be0a3e943653c78212b96ff524b74c9ec456b17cdfb950cc97645c577b2e09ff41dde" + + "b03afb3adaa381cc0f7c1d95663ef22a0f72f2c45613ae8e2b2d1efc96e8463c7d1d8a1d" + + "7e3b35df8fe73a301fc3f804b942b2b3afa337ff105fc1462b7b1c1d75eb4566c8665e59" + + "f80393b0adbf8004ff6c3327ed34f007cb4a3348a7d55e06e3a08202ea308202e6308202" + + "e2308201caa003020102020101300d06092a864886f70d01010b05003019311730150603" + + "550403130e4f43535020526573706f6e646572301e170d3135303133303135353033335a" + + "170d3136303133303135353033335a3019311730150603550403130e4f43535020526573" + + "706f6e64657230820122300d06092a864886f70d01010105000382010f003082010a0282" + + "010100e8155f2d3e6f2e8d14c62a788bd462f9f844e7a6977c83ef1099f0f6616ec5265b" + + "56f356e62c5400f0b06a2e7945a82752c636df32a895152d6074df1701dc6ccfbcbec75a" + + "70bd2b55ae2be7e6cad3b5fd4cd5b7790ab401a436d3f5f346074ffde8a99d5b723350f0" + + "a112076614b12ef79c78991b119453445acf2416ab0046b540db14c9fc0f27b8989ad0f6" + + "3aa4b8aefc91aa8a72160c36307c60fec78a93d3fddf4259902aa77e7332971c7d285b6a" + + "04f648993c6922a3e9da9adf5f81508c3228791843e5d49f24db2f1290bafd97e655b104" + + "9a199f652cd603c4fafa330c390b0da78fbbc67e8fa021cbd74eb96222b12ace31a77dcf" + + "920334dc94581b0203010001a3353033300e0603551d0f0101ff04040302078030130603" + + "551d25040c300a06082b06010505070309300c0603551d130101ff04023000300d06092a" + + "864886f70d01010b05000382010100718012761b5063e18f0dc44644d8e6ab861231c15f" + + "d5357805425d82aec1de85bf6d3e30fce205e3e3b8b795bbe52e40a439286d22889064f4" + + "aeeb150359b9425f1da51b3a5c939018555d13ac42c565a0603786a919328f326709dce5" + + "2c22ad958ecb7873b9771d1148b1c4be2efe80ba868919fc9f68b6090c2f33c156d67156" + + "e42766a50b5d51e79637b7e58af74c2a951b1e642fa7741fec982cc937de37eff59e2005" + + "d5939bfc031589ca143e6e8ab83f40ee08cc20a6b4a95a318352c28d18528dcaf966705d" + + "e17afa19d6e8ae91ddf33179d16ebb6ac2c69cae8373d408ebf8c55308be6c04d93a2543" + + "9a94299a65a709756c7a3e568be049d5c38839" + const ocspRequestHex = "3051304f304d304b3049300906052b0e03021a05000414c0fe0278fc99188891b3f212e9" + "c7e1b21ab7bfc004140dfc1df0a9e0f01ce7f2b213177e6f8d157cd4f60210017f77deb3" + "bcbb235d44ccc7dba62e72"