cryptocore: disentangle algorithm / library implementation name

Used in gocryptfs-xray, and will also be used in -info.

gocryptfs-xray/xray_main.go

@@ -39,7 +39,7 @@ func errExit(err error) {
 
 func prettyPrintHeader(h *contentenc.FileHeader, algo cryptocore.AEADTypeEnum) {
 	id := hex.EncodeToString(h.ID)
-	fmt.Printf("Header: Version: %d, Id: %s, assuming %s mode\n", h.Version, id, algo.Name)
+	fmt.Printf("Header: Version: %d, Id: %s, assuming %s mode\n", h.Version, id, algo.Algo)
 }
 
 // printVersion prints a version string like this:

gocryptfs-xray/xray_tests/aesgcm_fs.xray.txt

@@ -1,3 +1,3 @@
-Header: Version: 2, Id: 8932adf303fe0289679d47fa84d2b241, assuming AES-GCM-256-Go mode
+Header: Version: 2, Id: 8932adf303fe0289679d47fa84d2b241, assuming AES-GCM-256 mode
 Block  0: IV: c8536b4bfd92f5dc3c1e2ac29f116d4a, Tag: 22b20422749b2f4bba67ec7d3bb1ac34, Offset:    18 Len: 4128
 Block  1: IV: 2de68f4965779bb137ef2b3c20453556, Tag: 3e8758d6872234b1fffab2504e623467, Offset:  4146 Len: 936

gocryptfs-xray/xray_tests/aessiv_fs.xray.txt

@@ -1,3 +1,3 @@
-Header: Version: 2, Id: d839806747918e345633fcdd0988e67c, assuming AES-SIV-512-Go mode
+Header: Version: 2, Id: d839806747918e345633fcdd0988e67c, assuming AES-SIV-512 mode
 Block  0: IV: 1d3ce2b13260f83766ccf9a670478a4b, Tag: 0b6f95bd523b4c93704e15ecc6bef8e7, Offset:    18 Len: 4128
 Block  1: IV: 7eb947d2adf18adf3bed39bbc8052968, Tag: 1a272903e5a987f53f07344840387c20, Offset:  4146 Len: 936

internal/cryptocore/cryptocore.go

@@ -28,28 +28,36 @@ const (
 
 // AEADTypeEnum indicates the type of AEAD backend in use.
 type AEADTypeEnum struct {
-	Name      string
+	// Algo is the encryption algorithm. Example: "AES-GCM-256"
+	Algo string
+	// Lib is the library where Algo is implemented. Either "Go" or "OpenSSL".
+	Lib       string
 	NonceSize int
 }
 
+// String returns something like "AES-GCM-256-OpenSSL"
+func (a AEADTypeEnum) String() string {
+	return a.Algo + "-" + a.Lib
+}
+
 // BackendOpenSSL specifies the OpenSSL AES-256-GCM backend.
 // "AES-GCM-256-OpenSSL" in gocryptfs -speed.
-var BackendOpenSSL AEADTypeEnum = AEADTypeEnum{"AES-GCM-256-OpenSSL", 16}
+var BackendOpenSSL AEADTypeEnum = AEADTypeEnum{"AES-GCM-256", "OpenSSL", 16}
 
 // BackendGoGCM specifies the Go based AES-256-GCM backend.
 // "AES-GCM-256-Go" in gocryptfs -speed.
-var BackendGoGCM AEADTypeEnum = AEADTypeEnum{"AES-GCM-256-Go", 16}
+var BackendGoGCM AEADTypeEnum = AEADTypeEnum{"AES-GCM-256", "Go", 16}
 
 // BackendAESSIV specifies an AESSIV backend.
 // "AES-SIV-512-Go" in gocryptfs -speed.
-var BackendAESSIV AEADTypeEnum = AEADTypeEnum{"AES-SIV-512-Go", siv_aead.NonceSize}
+var BackendAESSIV AEADTypeEnum = AEADTypeEnum{"AES-SIV-512", "Go", siv_aead.NonceSize}
 
 // BackendXChaCha20Poly1305 specifies XChaCha20-Poly1305-Go.
 // "XChaCha20-Poly1305-Go" in gocryptfs -speed.
-var BackendXChaCha20Poly1305 AEADTypeEnum = AEADTypeEnum{"XChaCha20-Poly1305-Go", chacha20poly1305.NonceSizeX}
+var BackendXChaCha20Poly1305 AEADTypeEnum = AEADTypeEnum{"XChaCha20-Poly1305", "Go", chacha20poly1305.NonceSizeX}
 
 // BackendXChaCha20Poly1305OpenSSL specifies XChaCha20-Poly1305-OpenSSL.
-var BackendXChaCha20Poly1305OpenSSL AEADTypeEnum = AEADTypeEnum{"XChaCha20-Poly1305-OpenSSL", chacha20poly1305.NonceSizeX}
+var BackendXChaCha20Poly1305OpenSSL AEADTypeEnum = AEADTypeEnum{"XChaCha20-Poly1305", "OpenSSL", chacha20poly1305.NonceSizeX}
 
 // CryptoCore is the low level crypto implementation.
 type CryptoCore struct {
@@ -176,7 +184,7 @@ func New(key []byte, aeadType AEADTypeEnum, IVBitLen int, useHKDF bool) *CryptoC
 			log.Panic(err)
 		}
 	} else {
-		log.Panicf("unknown cipher backend %q", aeadType.Name)
+		log.Panicf("unknown cipher backend %q", aeadType)
 	}
 
 	if aeadCipher.NonceSize()*8 != IVBitLen {
@@ -205,7 +213,7 @@ type wiper interface {
 func (c *CryptoCore) Wipe() {
 	be := c.AEADBackend
 	if be == BackendOpenSSL || be == BackendAESSIV {
-		tlog.Debug.Printf("CryptoCore.Wipe: Wiping AEADBackend %s key", be.Name)
+		tlog.Debug.Printf("CryptoCore.Wipe: Wiping AEADBackend %q key", be)
 		// We don't use "x, ok :=" because we *want* to crash loudly if the
 		// type assertion fails.
 		w := c.AEADCipher.(wiper)

internal/speed/speed.go

@@ -42,11 +42,11 @@ func Run() {
 		f         func(*testing.B)
 		preferred bool
 	}{
-		{name: cryptocore.BackendOpenSSL.Name, f: bStupidGCM, preferred: stupidgcm.PreferOpenSSLAES256GCM()},
-		{name: cryptocore.BackendGoGCM.Name, f: bGoGCM, preferred: !stupidgcm.PreferOpenSSLAES256GCM()},
-		{name: cryptocore.BackendAESSIV.Name, f: bAESSIV, preferred: false},
-		{name: cryptocore.BackendXChaCha20Poly1305OpenSSL.Name, f: bStupidXchacha, preferred: stupidgcm.PreferOpenSSLXchacha20poly1305()},
-		{name: cryptocore.BackendXChaCha20Poly1305.Name, f: bXchacha20poly1305, preferred: !stupidgcm.PreferOpenSSLXchacha20poly1305()},
+		{name: cryptocore.BackendOpenSSL.String(), f: bStupidGCM, preferred: stupidgcm.PreferOpenSSLAES256GCM()},
+		{name: cryptocore.BackendGoGCM.String(), f: bGoGCM, preferred: !stupidgcm.PreferOpenSSLAES256GCM()},
+		{name: cryptocore.BackendAESSIV.String(), f: bAESSIV, preferred: false},
+		{name: cryptocore.BackendXChaCha20Poly1305OpenSSL.String(), f: bStupidXchacha, preferred: stupidgcm.PreferOpenSSLXchacha20poly1305()},
+		{name: cryptocore.BackendXChaCha20Poly1305.String(), f: bXchacha20poly1305, preferred: !stupidgcm.PreferOpenSSLXchacha20poly1305()},
 	}
 	for _, b := range bTable {
 		fmt.Printf("%-26s\t", b.name)