Remove kdfs that were only used internally in LMP

Bug: 17439091
Change-Id: I55f92984c8234362597be3976a10626a0ed8763f

cryptfs.c

@@ -235,20 +235,6 @@ static int keymaster_sign_object(struct crypt_mnt_ftr *ftr,
     //    necessary, but is necessary to ensure consistency in
     //    implementations.
     switch (ftr->kdf_type) {
-        case KDF_SCRYPT_KEYMASTER_UNPADDED:
-            // This is broken: It produces a message which is shorter than
-            // the public modulus, failing criterion 2.
-            memcpy(to_sign, object, object_size);
-            to_sign_size = object_size;
-            SLOGI("Signing unpadded object");
-            break;
-        case KDF_SCRYPT_KEYMASTER_BADLY_PADDED:
-            // This is broken: Since the value of object is uniformly
-            // distributed, it produces a message that is larger than the
-            // public modulus with probability 0.25.
-            memcpy(to_sign, object, min(RSA_KEY_SIZE_BYTES, object_size));
-            SLOGI("Signing end-padded object");
-            break;
         case KDF_SCRYPT_KEYMASTER:
             // This ensures the most significant byte of the signed message
             // is zero.  We could have zero-padded to the left instead, but
@@ -1270,8 +1256,6 @@ static int encrypt_master_key(const char *passwd, const unsigned char *salt,
     get_device_scrypt_params(crypt_ftr);
 
     switch (crypt_ftr->kdf_type) {
-    case KDF_SCRYPT_KEYMASTER_UNPADDED:
-    case KDF_SCRYPT_KEYMASTER_BADLY_PADDED:
     case KDF_SCRYPT_KEYMASTER:
         if (keymaster_create_key(crypt_ftr)) {
             SLOGE("keymaster_create_key failed");
@@ -1392,9 +1376,7 @@ static int decrypt_master_key_aux(char *passwd, unsigned char *salt,
 
 static void get_kdf_func(struct crypt_mnt_ftr *ftr, kdf_func *kdf, void** kdf_params)
 {
-    if (ftr->kdf_type == KDF_SCRYPT_KEYMASTER_UNPADDED ||
-        ftr->kdf_type == KDF_SCRYPT_KEYMASTER_BADLY_PADDED ||
-        ftr->kdf_type == KDF_SCRYPT_KEYMASTER) {
+    if (ftr->kdf_type == KDF_SCRYPT_KEYMASTER) {
         *kdf = scrypt_keymaster;
         *kdf_params = ftr;
     } else if (ftr->kdf_type == KDF_SCRYPT) {

cryptfs.h

@@ -71,10 +71,7 @@
 /* Key Derivation Function algorithms */
 #define KDF_PBKDF2 1
 #define KDF_SCRYPT 2
-/* TODO(paullawrence): Remove KDF_SCRYPT_KEYMASTER_UNPADDED and KDF_SCRYPT_KEYMASTER_BADLY_PADDED
- * when it is safe to do so. */
-#define KDF_SCRYPT_KEYMASTER_UNPADDED 3
-#define KDF_SCRYPT_KEYMASTER_BADLY_PADDED 4
+/* Algorithms 3 & 4 deprecated before shipping outside of google, so removed */
 #define KDF_SCRYPT_KEYMASTER 5
 
 /* Maximum allowed keymaster blob size. */