SBOM Attestor Improvements (#281)

SBOM Attestor type-specific unmarshalling of SPDX and CycloneDX and additional subjects

Signed-off-by: John Kjell <[email protected]>

attestation/sbom/sbom.go

@@ -15,17 +15,21 @@
 package sbom
 
 import (
+	"bytes"
+	"crypto"
 	"encoding/json"
 	"fmt"
 	"io"
 	"os"
 	"path/filepath"
 
+	"github.com/CycloneDX/cyclonedx-go"
 	"github.com/in-toto/go-witness/attestation"
 	"github.com/in-toto/go-witness/cryptoutil"
 	"github.com/in-toto/go-witness/log"
 	"github.com/in-toto/go-witness/registry"
 	"github.com/invopop/jsonschema"
+	"github.com/spdx/tools-golang/spdx"
 )
 
 const (
@@ -125,6 +129,14 @@ func (a *SBOMAttestor) MarshalJSON() ([]byte, error) {
 }
 
 func (a *SBOMAttestor) UnmarshalJSON(data []byte) error {
+	if bytes.HasPrefix(data, []byte(`{"spdxVersion":"SPDX-`)) {
+		a.predicateType = SPDXPredicateType
+	} else if bytes.HasPrefix(data, []byte(`{"$schema":"http://cyclonedx.org/schema/bom-`)) {
+		a.predicateType = CycloneDxPredicateType
+	} else {
+		log.Warn("Unknown sbom predicate type")
+	}
+
 	if err := json.Unmarshal(data, &a.SBOMDocument); err != nil {
 		return err
 	}
@@ -161,13 +173,49 @@ func (a *SBOMAttestor) getCandidate(ctx *attestation.AttestationContext) error {
 			return fmt.Errorf("error reading file: %s", path)
 		}
 
-		var sbomDocument interface{}
-		if err := json.Unmarshal(sbomBytes, &sbomDocument); err != nil {
-			log.Debugf("(attestation/sbom) error unmarshaling SBOM: %w", err)
-			continue
+		subjectsByName := make(map[string]string)
+		switch a.predicateType {
+		case SPDXPredicateType:
+			var document *spdx.Document
+			err := json.Unmarshal(sbomBytes, &document)
+			if err != nil {
+				return fmt.Errorf("error unmarshaling SPDX document: %w", err)
+			}
+
+			if document.DocumentName != "" {
+				subjectsByName["name"] = document.DocumentName
+			}
+
+			a.SBOMDocument = document
+		case CycloneDxPredicateType:
+			bom := cyclonedx.NewBOM()
+			decoder := cyclonedx.NewBOMDecoder(bytes.NewReader(sbomBytes), cyclonedx.BOMFileFormatJSON)
+			err := decoder.Decode(bom)
+			if err != nil {
+				return fmt.Errorf("error decoding CycloneDX BOM: %w", err)
+			}
+
+			if bom.Metadata.Component.Name != "" {
+				subjectsByName["name"] = bom.Metadata.Component.Name
+			}
+
+			if bom.Metadata.Component.Version != "" {
+				subjectsByName["version"] = bom.Metadata.Component.Version
+			}
+
+			a.SBOMDocument = bom
+		default:
+			return fmt.Errorf("unsupported predicate type: %s", a.predicateType)
 		}
 
-		a.SBOMDocument = sbomDocument
+		hashes := []cryptoutil.DigestValue{{Hash: crypto.SHA256}}
+		for k, v := range subjectsByName {
+			if ds, err := cryptoutil.CalculateDigestSetFromBytes([]byte(v), hashes); err == nil {
+				a.subjects[fmt.Sprintf("%s:%s", k, v)] = ds
+			} else {
+				log.Debugf("(attestation/sbom) failed to record %v subject: %w", k, err)
+			}
+		}
 
 		return nil
 	}

attestation/sbom/sbom_test.go

@@ -72,7 +72,7 @@ func TestAttest(t *testing.T) {
 		{"SPDX 2.3", "./boms/spdx-2.3/", "alpine.spdx-2-3.json", SPDXPredicateType, ""},
 		{"CycloneDx", "./boms/cyclonedx-json/", "alpine.cyclonedx.json", CycloneDxPredicateType, ""},
 		{"CycloneDx XML", "./boms/cyclonedx-xml/", "alpine.cyclonedx.xml", Type, "no SBOM file found"},
-		{"Bad JSON", "./boms/bad-json/", "bad.json", SPDXPredicateType, "no SBOM file found"},
+		{"Bad JSON", "./boms/bad-json/", "bad.json", SPDXPredicateType, "error unmarshaling SPDX document: invalid character '\\n' in string literal"},
 		{"No JSON", "./boms/emptyDir", "no.json", Type, "no products to attest"},
 	}
 

go.mod

@@ -6,6 +6,7 @@ toolchain go1.22.4
 
 require (
 	cloud.google.com/go/kms v1.15.9
+	github.com/CycloneDX/cyclonedx-go v0.9.0
 	github.com/aws/aws-sdk-go-v2/config v1.27.18
 	github.com/aws/aws-sdk-go-v2/service/kms v1.31.3
 	github.com/digitorus/pkcs7 v0.0.0-20230818184609-3a137a874352
@@ -24,6 +25,7 @@ require (
 	github.com/open-policy-agent/opa v0.64.0
 	github.com/owenrumney/go-sarif v1.1.1
 	github.com/sigstore/fulcio v1.4.5
+	github.com/spdx/tools-golang v0.5.4
 	github.com/spiffe/go-spiffe/v2 v2.1.7
 	github.com/stretchr/testify v1.9.0
 	go.step.sm/crypto v0.44.8
@@ -42,6 +44,7 @@ require (
 	dario.cat/mergo v1.0.0 // indirect
 	filippo.io/edwards25519 v1.1.0 // indirect
 	github.com/agnivade/levenshtein v1.1.1 // indirect
+	github.com/anchore/go-struct-converter v0.0.0-20221118182256-c68fdcfa2092 // indirect
 	github.com/apparentlymart/go-textseg/v15 v15.0.0 // indirect
 	github.com/aws/aws-sdk-go-v2 v1.27.2 // indirect
 	github.com/aws/aws-sdk-go-v2/credentials v1.17.18 // indirect

go.sum

@@ -16,6 +16,8 @@ dario.cat/mergo v1.0.0/go.mod h1:uNxQE+84aUszobStD9th8a29P2fMDhsBdgRYvZOxGmk=
 filippo.io/edwards25519 v1.1.0 h1:FNf4tywRC1HmFuKW5xopWpigGjJKiJSV0Cqo0cJWDaA=
 filippo.io/edwards25519 v1.1.0/go.mod h1:BxyFTGdWcka3PhytdK4V28tE5sGfRvvvRV7EaN4VDT4=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/CycloneDX/cyclonedx-go v0.9.0 h1:inaif7qD8bivyxp7XLgxUYtOXWtDez7+j72qKTMQTb8=
+github.com/CycloneDX/cyclonedx-go v0.9.0/go.mod h1:NE/EWvzELOFlG6+ljX/QeMlVt9VKcTwu8u0ccsACEsw=
 github.com/Microsoft/go-winio v0.5.2/go.mod h1:WpS1mjBmmwHBEWmogvA2mj8546UReBk4v8QkMxJ6pZY=
 github.com/Microsoft/go-winio v0.6.1 h1:9/kr64B9VUZrLm5YYwbGtUJnMgqWVOdUAXu6Migciow=
 github.com/Microsoft/go-winio v0.6.1/go.mod h1:LRdKpFKfdobln8UmuiYcKPot9D2v6svN5+sAH+4kjUM=
@@ -25,6 +27,8 @@ github.com/ProtonMail/go-crypto v1.0.0 h1:LRuvITjQWX+WIfr930YHG2HNfjR1uOfyf5vE0k
 github.com/ProtonMail/go-crypto v1.0.0/go.mod h1:EjAoLdwvbIOoOQr3ihjnSoLZRtE8azugULFRteWMNc0=
 github.com/agnivade/levenshtein v1.1.1 h1:QY8M92nrzkmr798gCo3kmMyqXFzdQVpxLlGPRBij0P8=
 github.com/agnivade/levenshtein v1.1.1/go.mod h1:veldBMzWxcCG2ZvUTKD2kJNRdCk5hVbJomOvKkmgYbo=
+github.com/anchore/go-struct-converter v0.0.0-20221118182256-c68fdcfa2092 h1:aM1rlcoLz8y5B2r4tTLMiVTrMtpfY0O8EScKJxaSaEc=
+github.com/anchore/go-struct-converter v0.0.0-20221118182256-c68fdcfa2092/go.mod h1:rYqSE9HbjzpHTI74vwPvae4ZVYZd1lue2ta6xHPdblA=
 github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be h1:9AeTilPcZAjCFIImctFaOjnTIavg87rW78vTPkQqLI8=
 github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be/go.mod h1:ySMOLuWl6zY27l47sB3qLNK6tF2fkHG55UZxx8oIVo4=
 github.com/apparentlymart/go-textseg/v13 v13.0.0/go.mod h1:ZK2fH7c4NqDTLtiYLvIkEghdlcqw7yxLeM89kiTRPUo=
@@ -68,6 +72,8 @@ github.com/bahlo/generic-list-go v0.2.0 h1:5sz/EEAK+ls5wF+NeqDpk5+iNdMDXrh3z3nPn
 github.com/bahlo/generic-list-go v0.2.0/go.mod h1:2KvAjgMlE5NNynlg/5iLrrCCZ2+5xWbdbCW3pNTGyYg=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/bradleyjkemp/cupaloy/v2 v2.8.0 h1:any4BmKE+jGIaMpnU8YgH/I2LPiLBufr6oMMlVBbn9M=
+github.com/bradleyjkemp/cupaloy/v2 v2.8.0/go.mod h1:bm7JXdkRd4BHJk9HpwqAI8BoAY1lps46Enkdqw6aRX0=
 github.com/buger/jsonparser v1.1.1 h1:2PnMjfWD7wBILjqQbt530v576A/cAbQvEW9gGIpYMUs=
 github.com/buger/jsonparser v1.1.1/go.mod h1:6RYKKt7H4d4+iWqouImQ9R2FZql3VbhNgx27UK13J/0=
 github.com/bwesterb/go-ristretto v1.2.3/go.mod h1:fUIoIZaG73pV5biE2Blr2xEzDoMj7NFEuV9ekS419A0=
@@ -306,24 +312,31 @@ github.com/skratchdot/open-golang v0.0.0-20200116055534-eef842397966 h1:JIAuq3EE
 github.com/skratchdot/open-golang v0.0.0-20200116055534-eef842397966/go.mod h1:sUM3LWHvSMaG192sy56D9F7CNvL7jUJVXoqM1QKLnog=
 github.com/smallstep/assert v0.0.0-20200723003110-82e2b9b3b262 h1:unQFBIznI+VYD1/1fApl1A+9VcBk+9dcqGfnePY87LY=
 github.com/smallstep/assert v0.0.0-20200723003110-82e2b9b3b262/go.mod h1:MyOHs9Po2fbM1LHej6sBUT8ozbxmMOFG+E+rx/GSGuc=
+github.com/spdx/gordf v0.0.0-20201111095634-7098f93598fb/go.mod h1:uKWaldnbMnjsSAXRurWqqrdyZen1R7kxl8TkmWk2OyM=
+github.com/spdx/tools-golang v0.5.4 h1:fRW4iz16P1ZCUtWStFqS6YiMgnK7WgfTFU/lrsYlvqY=
+github.com/spdx/tools-golang v0.5.4/go.mod h1:MVIsXx8ZZzaRWNQpUDhC4Dud34edUYJYecciXgrw5vE=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spiffe/go-spiffe/v2 v2.1.7 h1:VUkM1yIyg/x8X7u1uXqSRVRCdMdfRIEdFBzpqoeASGk=
 github.com/spiffe/go-spiffe/v2 v2.1.7/go.mod h1:QJDGdhXllxjxvd5B+2XnhhXB/+rC8gr+lNrtOryiWeE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/tchap/go-patricia/v2 v2.3.1 h1:6rQp39lgIYZ+MHmdEq4xzuk1t7OdC35z/xm0BGhTkes=
 github.com/tchap/go-patricia/v2 v2.3.1/go.mod h1:VZRHKAb53DLaG+nA9EaYYiaEx6YztwDlLElMsnSHD4k=
+github.com/terminalstatic/go-xsd-validate v0.1.5 h1:RqpJnf6HGE2CB/lZB1A8BYguk8uRtcvYAPLCF15qguo=
+github.com/terminalstatic/go-xsd-validate v0.1.5/go.mod h1:18lsvYFofBflqCrvo1umpABZ99+GneNTw2kEEc8UPJw=
 github.com/titanous/rocacheck v0.0.0-20171023193734-afe73141d399 h1:e/5i7d4oYZ+C1wj2THlRK+oAhjeS/TRQwMfkIuet3w0=
 github.com/titanous/rocacheck v0.0.0-20171023193734-afe73141d399/go.mod h1:LdwHTNJT99C5fTAzDz0ud328OgXz+gierycbcIx2fRs=
 github.com/vmihailenco/msgpack/v4 v4.3.12/go.mod h1:gborTTJjAo/GWTqqRjrLCn9pgNN+NXzzngzBKDPIqw4=
@@ -336,6 +349,8 @@ github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb h1:zGWFAtiMc
 github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb/go.mod h1:N2zxlSyiKSe5eX1tZViRH5QA0qijqEDrYZiPEAiq3wU=
 github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 h1:EzJWgHovont7NscjpAxXsDA8S8BMYve8Y5+7cuRE7R0=
 github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415/go.mod h1:GwrjFmJcFw6At/Gs6z4yjiIwzuJ1/+UwLxMQDVQXShQ=
+github.com/xeipuuv/gojsonschema v1.2.0 h1:LhYJRs+L4fBtjZUfuSZIKGeVu0QRy8e5Xi7D17UxZ74=
+github.com/xeipuuv/gojsonschema v1.2.0/go.mod h1:anYRn/JVcOK2ZgGU+IjEV4nwlhoK5sQluxsYJ78Id3Y=
 github.com/yashtewari/glob-intersection v0.2.0 h1:8iuHdN88yYuCzCdjt0gDe+6bAhUwBeEWqThExu54RFg=
 github.com/yashtewari/glob-intersection v0.2.0/go.mod h1:LK7pIC3piUjovexikBbJ26Yml7g8xa5bsjfx2v1fwok=
 github.com/ysmood/fetchup v0.2.3 h1:ulX+SonA0Vma5zUFXtv52Kzip/xe7aj4vqT5AJwQ+ZQ=