feat: extract username as vendor candidate from github/gitlab

Signed-off-by: Weston Steimel <weston.steimel@anchore.com>

syft/pkg/cataloger/common/cpe/vendors_from_url.go

@@ -1,33 +1,56 @@
 package cpe
 
 import (
+	"regexp"
 	"strings"
+
+	"github.com/anchore/syft/internal"
 )
 
 var (
-	urlPrefixVendors = map[string][]string{
+	urlPrefixToVendors = map[string][]string{
 		"https://www.gnu.org/":         {"gnu"},
 		"https://developer.gnome.org/": {"gnome"},
 		"https://www.ruby-lang.org/":   {"ruby-lang"},
 		"https://llvm.org/":            {"llvm"},
 		"https://www.isc.org/":         {"isc"},
 	}
+
+	vendorExtractionPatterns = []*regexp.Regexp{
+		regexp.MustCompile(`^https://(?:github|gitlab)\.com/(?P<vendor>[\w\-]*?)/.*$`),
+	}
 )
 
 func candidateVendorsFromURL(url string) fieldCandidateSet {
 	vendors := newFieldCandidateSet()
 
-	for urlPrefix, additionalVendors := range urlPrefixVendors {
+	for urlPrefix, additionalVendors := range urlPrefixToVendors {
 		if strings.HasPrefix(url, urlPrefix) {
 			for _, v := range additionalVendors {
 				vendors.add(fieldCandidate{
 					value:                       v,
 					disallowSubSelections:       true,
 					disallowDelimiterVariations: true,
 				})
+
+				return vendors
 			}
 		}
 	}
 
+	for _, p := range vendorExtractionPatterns {
+		groups := internal.MatchNamedCaptureGroups(p, url)
+
+		if v, ok := groups["vendor"]; ok {
+			vendors.add(fieldCandidate{
+				value:                       v,
+				disallowSubSelections:       true,
+				disallowDelimiterVariations: true,
+			})
+
+			return vendors
+		}
+	}
+
 	return vendors
 }

syft/pkg/cataloger/common/cpe/vendors_from_url_test.go

@@ -27,6 +27,31 @@ func Test_candidateVendorsFromURL(t *testing.T) {
 			url:      "https://www.gnu.org/software/make",
 			expected: []string{"gnu"},
 		},
+		{
+			name:     "github username as vendor",
+			url:      "https://github.com/armadillo/abcxyz-12345",
+			expected: []string{"armadillo"},
+		},
+		{
+			name:     "github username with - as vendor",
+			url:      "https://github.com/1234-abc-xyz/hello",
+			expected: []string{"1234-abc-xyz"},
+		},
+		{
+			name:     "gitlab username as vendor",
+			url:      "https://gitlab.com/armadillo/abcxyz-12345",
+			expected: []string{"armadillo"},
+		},
+		{
+			name:     "gitlab username with - as vendor",
+			url:      "https://gitlab.com/1234-abc-xyz/hello",
+			expected: []string{"1234-abc-xyz"},
+		},
+		{
+			name:     "github username as vendor from longer url",
+			url:      "https://github.com/armadillo/abcxyz-12345/a/b/c/d/e/f/g",
+			expected: []string{"armadillo"},
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {