Merge pull request #105 from paketo-buildpacks/sbom-deps

Adds support for DependencyLayerContributor and HelperLayerContributor to generate SBOMs

buildpack.go

@@ -28,6 +28,7 @@ import (
 	"github.com/heroku/color"
 
 	"github.com/paketo-buildpacks/libpak/bard"
+	"github.com/paketo-buildpacks/libpak/sbom"
 )
 
 // BuildpackConfiguration represents a build or launch configuration parameter.
@@ -80,13 +81,19 @@ type BuildpackDependency struct {
 	// Stacks are the stacks the dependency is compatible with.
 	Stacks []string `toml:"stacks"`
 
-	// Licenses are the stacks the dependency is distributed under.
+	// Licenses are the licenses the dependency is distributed under.
 	Licenses []BuildpackDependencyLicense `toml:"licenses"`
+
+	// CPEs are the Common Platform Enumeration identifiers for the dependency
+	CPEs []string `toml:"cpes"`
+
+	// PURL is the package URL that identifies the dependency
+	PURL string `toml:"purl"`
 }
 
 // AsBOMEntry renders a bill of materials entry describing the dependency.
 //
-// Deprecated: as of Buildpacks RFC 95, use `sherpa.SBOMScanner` instead
+// Deprecated: as of Buildpacks RFC 95, use `BuildpackDependency.AsSyftArtifact` instead
 func (b BuildpackDependency) AsBOMEntry() libcnb.BOMEntry {
 	return libcnb.BOMEntry{
 		Name: b.ID,
@@ -101,6 +108,33 @@ func (b BuildpackDependency) AsBOMEntry() libcnb.BOMEntry {
 	}
 }
 
+// AsSyftArtifact renders a bill of materials entry describing the dependency as Syft.
+func (b BuildpackDependency) AsSyftArtifact() (sbom.SyftArtifact, error) {
+	licenses := []string{}
+	for _, license := range b.Licenses {
+		licenses = append(licenses, license.Type)
+	}
+
+	sbomArtifact := sbom.SyftArtifact{
+		Name:      b.Name,
+		Version:   b.Version,
+		Type:      "UnknownPackage",
+		FoundBy:   "libpak",
+		Licenses:  licenses,
+		Locations: []sbom.SyftLocation{{Path: "buildpack.toml"}},
+		CPEs:      b.CPEs,
+		PURL:      b.PURL,
+	}
+
+	var err error
+	sbomArtifact.ID, err = sbomArtifact.Hash()
+	if err != nil {
+		return sbom.SyftArtifact{}, fmt.Errorf("unable to generate hash\n%w", err)
+	}
+
+	return sbomArtifact, nil
+}
+
 // BuildpackMetadata is an extension to libcnb.Buildpack's metadata with opinions.
 type BuildpackMetadata struct {
 
@@ -196,6 +230,16 @@ func NewBuildpackMetadata(metadata map[string]interface{}) (BuildpackMetadata, e
 				}
 			}
 
+			if v, ok := v["cpes"].([]interface{}); ok {
+				for _, v := range v {
+					d.CPEs = append(d.CPEs, v.(string))
+				}
+			}
+
+			if v, ok := v["purl"].(string); ok {
+				d.PURL = v
+			}
+
 			m.Dependencies = append(m.Dependencies, d)
 		}
 	}

buildpack_test.go

@@ -26,6 +26,7 @@ import (
 	"github.com/sclevine/spec"
 
 	"github.com/paketo-buildpacks/libpak"
+	"github.com/paketo-buildpacks/libpak/sbom"
 )
 
 func testBuildpack(t *testing.T, context spec.G, it spec.S) {
@@ -62,6 +63,37 @@ func testBuildpack(t *testing.T, context spec.G, it spec.S) {
 		}))
 	})
 
+	it("renders dependency as a SyftArtifact", func() {
+		dependency := libpak.BuildpackDependency{
+			ID:      "test-id",
+			Name:    "test-name",
+			Version: "1.1.1",
+			URI:     "test-uri",
+			SHA256:  "test-sha256",
+			Stacks:  []string{"test-stack"},
+			Licenses: []libpak.BuildpackDependencyLicense{
+				{
+					Type: "test-type",
+					URI:  "test-uri",
+				},
+			},
+			CPEs: []string{"test-cpe1", "test-cpe2"},
+			PURL: "test-purl",
+		}
+
+		Expect(dependency.AsSyftArtifact()).To(Equal(sbom.SyftArtifact{
+			ID:        "46713835f08d90b7",
+			Name:      "test-name",
+			Version:   "1.1.1",
+			Type:      "UnknownPackage",
+			FoundBy:   "libpak",
+			Licenses:  []string{"test-type"},
+			Locations: []sbom.SyftLocation{{Path: "buildpack.toml"}},
+			CPEs:      []string{"test-cpe1", "test-cpe2"},
+			PURL:      "test-purl",
+		}))
+	})
+
 	context("NewBuildpackMetadata", func() {
 		it("deserializes metadata", func() {
 			actual := map[string]interface{}{
@@ -86,6 +118,8 @@ func testBuildpack(t *testing.T, context spec.G, it spec.S) {
 								"uri":  "test-uri",
 							},
 						},
+						"cpes": []interface{}{"cpe:2.3:a:test-id:1.1.1"},
+						"purl": "pkg:generic:[email protected]",
 					},
 				},
 				"include-files": []interface{}{"test-include-file"},
@@ -114,6 +148,8 @@ func testBuildpack(t *testing.T, context spec.G, it spec.S) {
 								URI:  "test-uri",
 							},
 						},
+						CPEs: []string{"cpe:2.3:a:test-id:1.1.1"},
+						PURL: "pkg:generic:[email protected]",
 					},
 				},
 				IncludeFiles: []string{"test-include-file"},

dependency_cache_test.go

@@ -153,6 +153,8 @@ func testDependencyCache(t *testing.T, context spec.G, it spec.S) {
 						URI:  "test-uri",
 					},
 				},
+				CPEs: []string{"cpe:2.3:a:some:jre:11.0.2:*:*:*:*:*:*:*"},
+				PURL: "pkg:generic/[email protected]?arch=amd64",
 			}
 
 			dependencyCache = libpak.DependencyCache{

go.mod

@@ -5,10 +5,11 @@ go 1.15
 require (
 	github.com/CycloneDX/cyclonedx-go v0.4.0
 	github.com/Masterminds/semver/v3 v3.1.1
-	github.com/buildpacks/libcnb v1.24.1-0.20211118031525-6aa81e50810d
+	github.com/buildpacks/libcnb v1.25.0
 	github.com/creack/pty v1.1.17
 	github.com/heroku/color v0.0.6
 	github.com/imdario/mergo v0.3.12
+	github.com/mitchellh/hashstructure/v2 v2.0.2
 	github.com/onsi/gomega v1.17.0
 	github.com/pelletier/go-toml v1.9.4
 	github.com/sclevine/spec v1.4.0

go.sum

@@ -6,8 +6,8 @@ github.com/Masterminds/semver/v3 v3.1.1 h1:hLg3sBzpNErnxhQtUy/mmLR2I9foDujNK030I
 github.com/Masterminds/semver/v3 v3.1.1/go.mod h1:VPu/7SZ7ePZ3QOrcuXROw5FAcLl4a0cBrbBpGY/8hQs=
 github.com/bradleyjkemp/cupaloy/v2 v2.6.0 h1:knToPYa2xtfg42U3I6punFEjaGFKWQRXJwj0JTv4mTs=
 github.com/bradleyjkemp/cupaloy/v2 v2.6.0/go.mod h1:bm7JXdkRd4BHJk9HpwqAI8BoAY1lps46Enkdqw6aRX0=
-github.com/buildpacks/libcnb v1.24.1-0.20211118031525-6aa81e50810d h1:rAJsgF0p6rtUPGSTOCnCt/ofXKQM34wN+XKMXH3bNBE=
-github.com/buildpacks/libcnb v1.24.1-0.20211118031525-6aa81e50810d/go.mod h1:XX0+zHW8CNLNwiiwowgydAgWWfyDt8Lj1NcuWtkkBJQ=
+github.com/buildpacks/libcnb v1.25.0 h1:f0UWYUbXQ/vTX6SztGn+sP/F6cVSAbBQO4B5/R1LEP8=
+github.com/buildpacks/libcnb v1.25.0/go.mod h1:XX0+zHW8CNLNwiiwowgydAgWWfyDt8Lj1NcuWtkkBJQ=
 github.com/creack/pty v1.1.17 h1:QeVUsEDNrLBW4tMgZHvxy18sKtr6VI492kBhUfhDJNI=
 github.com/creack/pty v1.1.17/go.mod h1:MOBLtS5ELjhRRrroQr9kyvTxUAFNvYEK993ew/Vr4O4=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -41,6 +41,8 @@ github.com/mattn/go-colorable v0.1.2 h1:/bC9yWikZXAL9uJdulbSfyVNIR3n3trXl+v8+1sx
 github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-isatty v0.0.8 h1:HLtExJ+uU2HOZ+wI0Tt5DtUDrx8yhUqDcp7fYERX4CE=
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
+github.com/mitchellh/hashstructure/v2 v2.0.2 h1:vGKWl0YJqUNxE8d+h8f6NJLcCJrgbhC4NcD46KavDd4=
+github.com/mitchellh/hashstructure/v2 v2.0.2/go.mod h1:MG3aRVU/N29oo/V/IhBX8GR/zz4kQkprJgF2EVszyDE=
 github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
 github.com/nxadm/tail v1.4.8 h1:nPr65rt6Y5JFSKQO7qToXr7pePgD6Gwiw05lkbyAQTE=
 github.com/nxadm/tail v1.4.8/go.mod h1:+ncqLTQzXmGhMZNUePPaPqPvBxHAIsmXswZKocGu+AU=

layer.go

@@ -27,6 +27,7 @@ import (
 
 	"github.com/buildpacks/libcnb"
 
+	"github.com/paketo-buildpacks/libpak/sbom"
 	"github.com/paketo-buildpacks/libpak/sherpa"
 
 	"github.com/paketo-buildpacks/libpak/bard"
@@ -139,15 +140,18 @@ func NewDependencyLayer(dependency BuildpackDependency, cache DependencyCache, t
 		ExpectedTypes:    types,
 	}
 
-	entry := dependency.AsBOMEntry()
-	entry.Metadata["layer"] = c.LayerName()
+	var entry libcnb.BOMEntry
+	if dependency.PURL == "" && len(dependency.CPEs) == 0 {
+		entry = dependency.AsBOMEntry()
+		entry.Metadata["layer"] = c.LayerName()
 
-	if types.Launch {
-		entry.Launch = true
-	}
-	if !(types.Launch && !types.Cache && !types.Build) {
-		// launch-only layers are the only layers NOT guaranteed to be present in the build environment
-		entry.Build = true
+		if types.Launch {
+			entry.Launch = true
+		}
+		if !(types.Launch && !types.Cache && !types.Build) {
+			// launch-only layers are the only layers NOT guaranteed to be present in the build environment
+			entry.Build = true
+		}
 	}
 
 	return c, entry
@@ -168,6 +172,18 @@ func (d *DependencyLayerContributor) Contribute(layer libcnb.Layer, f Dependency
 		}
 		defer artifact.Close()
 
+		sbomArtifact, err := d.Dependency.AsSyftArtifact()
+		if err != nil {
+			return libcnb.Layer{}, fmt.Errorf("unable to get SBOM artifact %s\n%w", d.Dependency.ID, err)
+		}
+
+		sbomPath := layer.SBOMPath(libcnb.SyftJSON)
+		dep := sbom.NewSyftDependency(layer.Path, []sbom.SyftArtifact{sbomArtifact})
+		d.Logger.Debugf("Writing Syft SBOM at %s: %+v", sbomPath, dep)
+		if err := dep.WriteTo(sbomPath); err != nil {
+			return libcnb.Layer{}, fmt.Errorf("unable to write SBOM\n%w", err)
+		}
+
 		return f(artifact)
 	})
 }
@@ -210,14 +226,17 @@ func NewHelperLayer(buildpack libcnb.Buildpack, names ...string) (HelperLayerCon
 		BuildpackInfo: buildpack.Info,
 	}
 
-	entry := libcnb.BOMEntry{
-		Name: "helper",
-		Metadata: map[string]interface{}{
-			"layer":   c.Name(),
-			"names":   names,
-			"version": buildpack.Info.Version,
-		},
-		Launch: true,
+	var entry libcnb.BOMEntry
+	if buildpack.API == "0.6" || buildpack.API == "0.5" || buildpack.API == "0.4" || buildpack.API == "0.3" || buildpack.API == "0.2" || buildpack.API == "0.1" {
+		entry = libcnb.BOMEntry{
+			Name: "helper",
+			Metadata: map[string]interface{}{
+				"layer":   c.Name(),
+				"names":   names,
+				"version": buildpack.Info.Version,
+			},
+			Launch: true,
+		}
 	}
 
 	return c, entry
@@ -261,6 +280,51 @@ func (h HelperLayerContributor) Contribute(layer libcnb.Layer) (libcnb.Layer, er
 			}
 		}
 
+		sbomArtifact, err := h.AsSyftArtifact()
+		if err != nil {
+			return libcnb.Layer{}, fmt.Errorf("unable to get SBOM artifact for helper\n%w", err)
+		}
+
+		sbomPath := layer.SBOMPath(libcnb.SyftJSON)
+		dep := sbom.NewSyftDependency(layer.Path, []sbom.SyftArtifact{sbomArtifact})
+		h.Logger.Debugf("Writing Syft SBOM at %s: %+v", sbomPath, dep)
+		if err := dep.WriteTo(sbomPath); err != nil {
+			return libcnb.Layer{}, fmt.Errorf("unable to write SBOM\n%w", err)
+		}
+
 		return layer, nil
 	})
 }
+
+func (h HelperLayerContributor) AsSyftArtifact() (sbom.SyftArtifact, error) {
+	licenses := []string{}
+	for _, license := range h.BuildpackInfo.Licenses {
+		licenses = append(licenses, license.Type)
+	}
+
+	locations := []sbom.SyftLocation{}
+	cpes := []string{}
+	for _, name := range h.Names {
+		locations = append(locations, sbom.SyftLocation{Path: name})
+		cpes = append(cpes, fmt.Sprintf("cpe:2.3:a:%s:%s:%s:*:*:*:*:*:*:*",
+			h.BuildpackInfo.ID, name, h.BuildpackInfo.Version))
+	}
+
+	artifact := sbom.SyftArtifact{
+		Name:      "helper",
+		Version:   h.BuildpackInfo.Version,
+		Type:      "UnknownPackage",
+		FoundBy:   "libpak",
+		Licenses:  licenses,
+		Locations: locations,
+		CPEs:      cpes,
+		PURL:      fmt.Sprintf("pkg:generic/%s@%s", h.BuildpackInfo.ID, h.BuildpackInfo.Version),
+	}
+	var err error
+	artifact.ID, err = artifact.Hash()
+	if err != nil {
+		return sbom.SyftArtifact{}, fmt.Errorf("unable to generate hash\n%w", err)
+	}
+
+	return artifact, nil
+}