Remove support for MD2

No part of IKE/IPsec or X.509 uses MD2 anymore, so there really is no
reason to still support it (unlike MD4 that is used in EAP-MSCHAPv2,
MD5 that's used in EAP-MD5, or SHA-1 that's used for e.g. NAT-D hashes).

It caused test vectors to fail on systems where OpenSSL is built with
MD2 support but has it disabled at runtime.

src/libstrongswan/crypto/hashers/hasher.c

@@ -30,7 +30,6 @@ ENUM_BEGIN(hash_algorithm_names, HASH_SHA1, HASH_IDENTITY,
 	"HASH_IDENTITY");
 ENUM_NEXT(hash_algorithm_names, HASH_UNKNOWN, HASH_SHA3_512, HASH_IDENTITY,
 	"HASH_UNKNOWN",
-	"HASH_MD2",
 	"HASH_MD4",
 	"HASH_MD5",
 	"HASH_SHA2_224",
@@ -48,7 +47,6 @@ ENUM_BEGIN(hash_algorithm_short_names, HASH_SHA1, HASH_IDENTITY,
 	"identity");
 ENUM_NEXT(hash_algorithm_short_names, HASH_UNKNOWN, HASH_SHA3_512, HASH_IDENTITY,
 	"unknown",
-	"md2",
 	"md4",
 	"md5",
 	"sha224",
@@ -66,7 +64,6 @@ ENUM_BEGIN(hash_algorithm_short_names_upper, HASH_SHA1, HASH_IDENTITY,
 	"IDENTITY");
 ENUM_NEXT(hash_algorithm_short_names_upper, HASH_UNKNOWN, HASH_SHA3_512, HASH_IDENTITY,
 	"UNKNOWN",
-	"MD2",
 	"MD4",
 	"MD5",
 	"SHA2_224",
@@ -91,8 +88,6 @@ size_t hasher_hash_size(hash_algorithm_t alg)
 			return HASH_SIZE_SHA384;
 		case HASH_SHA512:
 			return HASH_SIZE_SHA512;
-		case HASH_MD2:
-			return HASH_SIZE_MD2;
 		case HASH_MD4:
 			return HASH_SIZE_MD4;
 		case HASH_MD5:
@@ -121,9 +116,6 @@ hash_algorithm_t hasher_algorithm_from_oid(int oid)
 {
 	switch (oid)
 	{
-		case OID_MD2:
-		case OID_MD2_WITH_RSA:
-			return HASH_MD2;
 		case OID_MD5:
 		case OID_MD5_WITH_RSA:
 			return HASH_MD5;
@@ -323,7 +315,6 @@ integrity_algorithm_t hasher_algorithm_to_integrity(hash_algorithm_t alg,
 					return AUTH_HMAC_SHA2_512_512;
 			}
 			break;
-		case HASH_MD2:
 		case HASH_MD4:
 		case HASH_SHA224:
 		case HASH_SHA3_224:
@@ -350,7 +341,6 @@ bool hasher_algorithm_for_ikev2(hash_algorithm_t alg)
 		case HASH_SHA512:
 			return TRUE;
 		case HASH_UNKNOWN:
-		case HASH_MD2:
 		case HASH_MD4:
 		case HASH_MD5:
 		case HASH_SHA1:
@@ -373,9 +363,6 @@ int hasher_algorithm_to_oid(hash_algorithm_t alg)
 
 	switch (alg)
 	{
-		case HASH_MD2:
-			oid = OID_MD2;
-			break;
 		case HASH_MD5:
 			oid = OID_MD5;
 			break;
@@ -422,8 +409,6 @@ int hasher_signature_algorithm_to_oid(hash_algorithm_t alg, key_type_t key)
 		case KEY_RSA:
 			switch (alg)
 			{
-				case HASH_MD2:
-					return OID_MD2_WITH_RSA;
 				case HASH_MD5:
 					return OID_MD5_WITH_RSA;
 				case HASH_SHA1:

src/libstrongswan/crypto/hashers/hasher.h

@@ -45,17 +45,15 @@ enum hash_algorithm_t {
 	HASH_IDENTITY		= 5,
 	/* use private use range for algorithms not defined/permitted by RFC 7427 */
 	HASH_UNKNOWN 		= 1024,
-	HASH_MD2 			= 1025,
-	HASH_MD4			= 1026,
-	HASH_MD5 			= 1027,
-	HASH_SHA224			= 1028,
-	HASH_SHA3_224		= 1029,
-	HASH_SHA3_256		= 1030,
-	HASH_SHA3_384		= 1031,
-	HASH_SHA3_512		= 1032
+	HASH_MD4			= 1025,
+	HASH_MD5 			= 1026,
+	HASH_SHA224			= 1027,
+	HASH_SHA3_224		= 1028,
+	HASH_SHA3_256		= 1029,
+	HASH_SHA3_384		= 1030,
+	HASH_SHA3_512		= 1031
 };
 
-#define HASH_SIZE_MD2		16
 #define HASH_SIZE_MD4		16
 #define HASH_SIZE_MD5		16
 #define HASH_SIZE_SHA1		20

src/libstrongswan/crypto/xofs/xof.c

@@ -60,7 +60,6 @@ ext_out_function_t xof_mgf1_from_hash_algorithm(hash_algorithm_t alg)
 			return XOF_MGF1_SHA3_384;
 		case HASH_IDENTITY:
 		case HASH_UNKNOWN:
-		case HASH_MD2:
 		case HASH_MD4:
 		case HASH_MD5:
 			break;