Merge pull request #228 from tri-adam/dsse

DSSE support

go.mod

@@ -6,15 +6,31 @@ require (
 	github.com/ProtonMail/go-crypto v0.0.0-20221026131551-cf6655e29de4
 	github.com/google/uuid v1.3.0
 	github.com/sebdah/goldie/v2 v2.5.3
+	github.com/secure-systems-lab/go-securesystemslib v0.4.0
+	github.com/sigstore/sigstore v1.4.5
 	github.com/spf13/cobra v1.6.1
 	github.com/spf13/pflag v1.0.5
 )
 
 require (
 	github.com/cloudflare/circl v1.1.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/go-containerregistry v0.12.0 // indirect
 	github.com/inconshreveable/mousetrap v1.0.1 // indirect
+	github.com/letsencrypt/boulder v0.0.0-20220929215747-76583552c2be // indirect
+	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/sergi/go-diff v1.2.0 // indirect
-	golang.org/x/crypto v0.0.0-20210921155107-089bfa567519 // indirect
-	golang.org/x/sys v0.0.0-20211007075335-d3039528d8ac // indirect
+	github.com/theupdateframework/go-tuf v0.5.2-0.20220930112810-3890c1e7ace4 // indirect
+	github.com/titanous/rocacheck v0.0.0-20171023193734-afe73141d399 // indirect
+	golang.org/x/crypto v0.0.0-20220926161630-eccd6366d1be // indirect
+	golang.org/x/net v0.1.0 // indirect
+	golang.org/x/sys v0.1.0 // indirect
+	golang.org/x/term v0.1.0 // indirect
+	golang.org/x/text v0.4.0 // indirect
+	google.golang.org/genproto v0.0.0-20221014213838-99cd37c6964a // indirect
+	google.golang.org/grpc v1.50.1 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+	gopkg.in/square/go-jose.v2 v2.6.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,49 +1,109 @@
 github.com/ProtonMail/go-crypto v0.0.0-20221026131551-cf6655e29de4 h1:ra2OtmuW0AE5csawV4YXMNGNQQXvLRps3z2Z59OPO+I=
 github.com/ProtonMail/go-crypto v0.0.0-20221026131551-cf6655e29de4/go.mod h1:UBYPn8k0D56RtnR8RFQMjmh4KrZzWJ5o7Z9SYjossQ8=
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/bwesterb/go-ristretto v1.2.0/go.mod h1:fUIoIZaG73pV5biE2Blr2xEzDoMj7NFEuV9ekS419A0=
+github.com/cespare/xxhash/v2 v2.1.2 h1:YRXhKfTDauu4ajMg1TPgFO5jnlC2HCbmLXMcTG5cbYE=
 github.com/cloudflare/circl v1.1.0 h1:bZgT/A+cikZnKIwn7xL2OBj012Bmvho/o6RpRvv3GKY=
 github.com/cloudflare/circl v1.1.0/go.mod h1:prBCrKB9DV4poKZY1l9zBXg2QJY7mvgRvtMxxK7fi4I=
+github.com/codahale/rfc6979 v0.0.0-20141003034818-6a90f24967eb h1:EDmT6Q9Zs+SbUoc7Ik9EfrFqcylYqgPZ9ANSbTAntnE=
 github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 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/facebookgo/clock v0.0.0-20150410010913-600d898af40a h1:yDWHCSQ40h88yih2JAcL6Ls/kVkSE8GFACTGVnMPruw=
+github.com/facebookgo/limitgroup v0.0.0-20150612190941-6abd8d71ec01 h1:IeaD1VDVBPlx3viJT9Md8if8IxxJnO+x0JCGb054heg=
+github.com/facebookgo/muster v0.0.0-20150708232844-fd3d7953fd52 h1:a4DFiKFJiDRGFD1qIcqGLX/WlUMD9dyLSLDt+9QZgt8=
+github.com/go-test/deep v1.0.8 h1:TDsG77qcSprGbC6vTN8OuXp5g+J+b5Pcguhf7Zt61VM=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/golang/protobuf v1.5.2 h1:ROPKBNFfQgOUMifHyP+KYbvpjbdoFNs+aK7DXlji0Tw=
+github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-containerregistry v0.12.0 h1:nidOEtFYlgPCRqxCKj/4c/js940HVWplCWc5ftdfdUA=
+github.com/google/go-containerregistry v0.12.0/go.mod h1:sdIK+oHQO7B93xI8UweYdl887YhuIwg9vz8BSLH3+8k=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/honeycombio/beeline-go v1.10.0 h1:cUDe555oqvw8oD76BQJ8alk7FP0JZ/M/zXpNvOEDLDc=
+github.com/honeycombio/libhoney-go v1.16.0 h1:kPpqoz6vbOzgp7jC6SR7SkNj7rua7rgxvznI6M3KdHc=
 github.com/inconshreveable/mousetrap v1.0.1 h1:U3uMjPSQEBMNp1lFxmllqCPM6P5u/Xq7Pgzkat/bFNc=
 github.com/inconshreveable/mousetrap v1.0.1/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/jmhodges/clock v0.0.0-20160418191101-880ee4c33548 h1:dYTbLf4m0a5u0KLmPfB6mgxbcV7588bOCx79hxa5Sr4=
+github.com/klauspost/compress v1.15.11 h1:Lcadnb3RKGin4FYM/orgq0qde+nc15E5Cbqg4B9Sx9c=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/letsencrypt/boulder v0.0.0-20220929215747-76583552c2be h1:Cx2bsfM27RBF/45zP1xhFN9FHDxo40LdYdE5L+GWVTw=
+github.com/letsencrypt/boulder v0.0.0-20220929215747-76583552c2be/go.mod h1:j/WMsOEcTSfy6VR1PkiIo20qH1V9iRRzb7ishoKkN0g=
+github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
+github.com/opencontainers/go-digest v1.0.0 h1:apOUWs51W5PlhuyGyz9FCeeBIOUDA/6nW8Oi/yOhh5U=
+github.com/opencontainers/go-digest v1.0.0/go.mod h1:0JzlMkj0TRzQZfJkVvzbP0HBR3IKzErnv2BNG4W4MAM=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
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+github.com/prometheus/client_golang v1.13.0 h1:b71QUfeo5M8gq2+evJdTPfZhYMAU0uKPkyPJ7TPsloU=
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-github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
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-golang.org/x/crypto v0.0.0-20210921155107-089bfa567519 h1:7I4JAnoQBe7ZtJcBaYHi5UtiO8tQHbUSXxL+pnGRANg=
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 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
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 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
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 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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 golang.org/x/sys v0.0.0-20211007075335-d3039528d8ac/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
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pkg/integrity/dsse.go

@@ -0,0 +1,213 @@
+// Copyright (c) 2022, Sylabs Inc. All rights reserved.
+// This software is licensed under a 3-clause BSD license. Please consult the LICENSE.md file
+// distributed with the sources of this project regarding your rights to use or distribute this
+// software.
+
+package integrity
+
+import (
+	"bytes"
+	"crypto"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+
+	"github.com/secure-systems-lab/go-securesystemslib/dsse"
+	"github.com/sigstore/sigstore/pkg/signature"
+	"github.com/sigstore/sigstore/pkg/signature/options"
+)
+
+const metadataMediaType = "application/vnd.sylabs.sif-metadata+json"
+
+type dsseEncoder struct {
+	es          *dsse.EnvelopeSigner
+	h           crypto.Hash
+	payloadType string
+}
+
+// newDSSEEncoder returns an encoder that signs messages in DSSE format according to opts, with key
+// material from ss. SHA256 is used as the hash algorithm, unless overridden by opts.
+func newDSSEEncoder(ss []signature.Signer, opts ...signature.SignOption) (*dsseEncoder, error) {
+	var so crypto.SignerOpts
+	for _, opt := range opts {
+		opt.ApplyCryptoSignerOpts(&so)
+	}
+
+	// If SignerOpts not explicitly supplied, set default hash algorithm.
+	if so == nil {
+		so = crypto.SHA256
+		opts = append(opts, options.WithCryptoSignerOpts(so))
+	}
+
+	dss := make([]dsse.SignVerifier, 0, len(ss))
+	for _, s := range ss {
+		ds, err := newDSSESigner(s, opts...)
+		if err != nil {
+			return nil, err
+		}
+
+		dss = append(dss, ds)
+	}
+
+	es, err := dsse.NewEnvelopeSigner(dss...)
+	if err != nil {
+		return nil, err
+	}
+
+	return &dsseEncoder{
+		es:          es,
+		h:           so.HashFunc(),
+		payloadType: metadataMediaType,
+	}, nil
+}
+
+// signMessage signs the message from r in DSSE format, and writes the result to w. On success, the
+// hash function is returned.
+func (en *dsseEncoder) signMessage(w io.Writer, r io.Reader) (crypto.Hash, error) {
+	body, err := io.ReadAll(r)
+	if err != nil {
+		return 0, err
+	}
+
+	e, err := en.es.SignPayload(en.payloadType, body)
+	if err != nil {
+		return 0, err
+	}
+
+	return en.h, json.NewEncoder(w).Encode(e)
+}
+
+type dsseDecoder struct {
+	vs          []signature.Verifier
+	threshold   int
+	payloadType string
+}
+
+// newDSSEDecoder returns a decoder that verifies messages in DSSE format using key material from
+// vs.
+func newDSSEDecoder(vs ...signature.Verifier) *dsseDecoder {
+	return &dsseDecoder{
+		vs:          vs,
+		threshold:   1, // Envelope considered verified if at least one verifier succeeds.
+		payloadType: metadataMediaType,
+	}
+}
+
+var (
+	errDSSEVerifyEnvelopeFailed  = errors.New("dsse: verify envelope failed")
+	errDSSEUnexpectedPayloadType = errors.New("unexpected DSSE payload type")
+)
+
+// verifyMessage reads a message from r, verifies its signature(s), and returns the message
+// contents. On success, the accepted public keys are set in vr.
+func (de *dsseDecoder) verifyMessage(r io.Reader, h crypto.Hash, vr *VerifyResult) ([]byte, error) {
+	vs := make([]dsse.Verifier, 0, len(de.vs))
+	for _, v := range de.vs {
+		dv, err := newDSSEVerifier(v, options.WithCryptoSignerOpts(h))
+		if err != nil {
+			return nil, err
+		}
+
+		vs = append(vs, dv)
+	}
+
+	v, err := dsse.NewMultiEnvelopeVerifier(de.threshold, vs...)
+	if err != nil {
+		return nil, err
+	}
+
+	var e dsse.Envelope
+	if err := json.NewDecoder(r).Decode(&e); err != nil {
+		return nil, err
+	}
+
+	vr.aks, err = v.Verify(&e)
+	if err != nil {
+		return nil, fmt.Errorf("%w: %v", errDSSEVerifyEnvelopeFailed, err)
+	}
+
+	if e.PayloadType != de.payloadType {
+		return nil, fmt.Errorf("%w: %v", errDSSEUnexpectedPayloadType, e.PayloadType)
+	}
+
+	return e.DecodeB64Payload()
+}
+
+type dsseSigner struct {
+	s    signature.Signer
+	opts []signature.SignOption
+	pub  crypto.PublicKey
+}
+
+// newDSSESigner returns a dsse.SignVerifier that uses s to sign according to opts. Note that the
+// returned value is suitable only for signing, and not verification.
+func newDSSESigner(s signature.Signer, opts ...signature.SignOption) (*dsseSigner, error) {
+	pub, err := s.PublicKey()
+	if err != nil {
+		return nil, err
+	}
+
+	return &dsseSigner{
+		s:    s,
+		opts: opts,
+		pub:  pub,
+	}, nil
+}
+
+// Sign signs the supplied data.
+func (s *dsseSigner) Sign(data []byte) ([]byte, error) {
+	return s.s.SignMessage(bytes.NewReader(data), s.opts...)
+}
+
+var errSignNotImplemented = errors.New("sign not implemented")
+
+// Verify is not implemented, but required for the dsse.SignVerifier interface.
+func (s *dsseSigner) Verify(data, sig []byte) error {
+	return errSignNotImplemented
+}
+
+// Public returns the public key associated with s.
+func (s *dsseSigner) Public() crypto.PublicKey {
+	return s.pub
+}
+
+// KeyID returns the key ID associated with s.
+func (s dsseSigner) KeyID() (string, error) {
+	return dsse.SHA256KeyID(s.pub)
+}
+
+type dsseVerifier struct {
+	v    signature.Verifier
+	opts []signature.VerifyOption
+	pub  crypto.PublicKey
+}
+
+// newDSSEVerifier returns a dsse.Verifier that uses v to verify according to opts.
+func newDSSEVerifier(v signature.Verifier, opts ...signature.VerifyOption) (*dsseVerifier, error) {
+	pub, err := v.PublicKey()
+	if err != nil {
+		return nil, err
+	}
+
+	return &dsseVerifier{
+		v:    v,
+		opts: opts,
+		pub:  pub,
+	}, nil
+}
+
+// Verify verifies that sig is a valid signature of data.
+func (v *dsseVerifier) Verify(data, sig []byte) error {
+	return v.v.VerifySignature(bytes.NewReader(sig), bytes.NewReader(data), v.opts...)
+}
+
+// Public returns the public key associated with v.
+func (v *dsseVerifier) Public() crypto.PublicKey {
+	return v.pub
+}
+
+// KeyID returns the key ID associated with v.
+func (v *dsseVerifier) KeyID() (string, error) {
+	return dsse.SHA256KeyID(v.pub)
+}