switch to go vendoring

vendor/github.com/crewjam/saml/xmlenc/digest.go

@@ -0,0 +1,56 @@
+package xmlenc
+
+import (
+	"crypto/sha1" //nolint:gosec // required for protocol support
+	"crypto/sha256"
+	"crypto/sha512"
+	"hash"
+
+	"golang.org/x/crypto/ripemd160"
+)
+
+type digestMethod struct {
+	algorithm string
+	hash      func() hash.Hash
+}
+
+func (dm digestMethod) Algorithm() string {
+	return dm.algorithm
+}
+
+func (dm digestMethod) Hash() hash.Hash {
+	return dm.hash()
+}
+
+var (
+	// SHA1 implements the SHA-1 digest method (which is considered insecure)
+	SHA1 = digestMethod{
+		algorithm: "http://www.w3.org/2000/09/xmldsig#sha1",
+		hash:      sha1.New,
+	}
+
+	// SHA256 implements the SHA-256 digest method
+	SHA256 = digestMethod{
+		algorithm: "http://www.w3.org/2000/09/xmldsig#sha256",
+		hash:      sha256.New,
+	}
+
+	// SHA512 implements the SHA-512 digest method
+	SHA512 = digestMethod{
+		algorithm: "http://www.w3.org/2000/09/xmldsig#sha512",
+		hash:      sha512.New,
+	}
+
+	// RIPEMD160 implements the RIPEMD160 digest method
+	RIPEMD160 = digestMethod{
+		algorithm: "http://www.w3.org/2000/09/xmldsig#ripemd160",
+		hash:      ripemd160.New,
+	}
+)
+
+func init() {
+	RegisterDigestMethod(SHA1)
+	RegisterDigestMethod(SHA256)
+	RegisterDigestMethod(SHA512)
+	RegisterDigestMethod(RIPEMD160)
+}