Remove old unused algorithm `m.secret_storage.v1.curve25519-aes-sha2`

https://github.com/uhoreg/matrix-doc/blob/symmetric_ssss/proposals/2472-symmetric-ssss.md
"The m.secret_storage.v1.curve25519-aes-sha2 method proposed in MSC1946 is removed."

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/crypto/CryptoConstants.kt

@@ -31,11 +31,6 @@ const val MXCRYPTO_ALGORITHM_MEGOLM = "m.megolm.v1.aes-sha2"
  */
 const val MXCRYPTO_ALGORITHM_MEGOLM_BACKUP = "m.megolm_backup.v1.curve25519-aes-sha2"
 
-/**
- * Secured Shared Storage algorithm constant.
- */
-const val SSSS_ALGORITHM_CURVE25519_AES_SHA2 = "m.secret_storage.v1.curve25519-aes-sha2"
-
 /* Secrets are encrypted using AES-CTR-256 and MACed using HMAC-SHA-256. **/
 const val SSSS_ALGORITHM_AES_HMAC_SHA2 = "m.secret_storage.v1.aes-hmac-sha2"
 

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/secrets/DefaultSharedSecretStorageService.kt

@@ -20,7 +20,6 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.withContext
 import org.matrix.android.sdk.api.MatrixCoroutineDispatchers
 import org.matrix.android.sdk.api.crypto.SSSS_ALGORITHM_AES_HMAC_SHA2
-import org.matrix.android.sdk.api.crypto.SSSS_ALGORITHM_CURVE25519_AES_SHA2
 import org.matrix.android.sdk.api.extensions.orFalse
 import org.matrix.android.sdk.api.listeners.ProgressListener
 import org.matrix.android.sdk.api.session.accountdata.SessionAccountDataService
@@ -319,27 +318,7 @@ internal class DefaultSharedSecretStorageService @Inject constructor(
                 ?: throw SharedSecretStorageError.ParsingError
 
         val algorithm = key.keyInfo.content
-        if (SSSS_ALGORITHM_CURVE25519_AES_SHA2 == algorithm.algorithm) {
+        if (SSSS_ALGORITHM_AES_HMAC_SHA2 == algorithm.algorithm) {
-            // TODO BMA
-            // val keySpec = secretKey as? RawBytesKeySpec ?: throw SharedSecretStorageError.BadKeyFormat
-            return withContext(cryptoCoroutineScope.coroutineContext + coroutineDispatchers.computation) {
-                // decrypt from recovery key
-                "TODO"
-                // TODO BMA
-                /*
-                withOlmDecryption { olmPkDecryption ->
-                    olmPkDecryption.setPrivateKey(keySpec.privateKey)
-                    olmPkDecryption.decrypt(OlmPkMessage()
-                            .apply {
-                                mCipherText = secretContent.ciphertext
-                                mEphemeralKey = secretContent.ephemeral
-                                mMac = secretContent.mac
-                            }
-                    )
-                }
-                 */
-            }
-        } else if (SSSS_ALGORITHM_AES_HMAC_SHA2 == algorithm.algorithm) {
             val keySpec = secretKey as? RawBytesKeySpec ?: throw SharedSecretStorageError.BadKeyFormat
             return withContext(cryptoCoroutineScope.coroutineContext + coroutineDispatchers.computation) {
                 decryptAesHmacSha2(keySpec, name, secretContent)
@@ -369,8 +348,7 @@ internal class DefaultSharedSecretStorageService @Inject constructor(
         val keyInfo = (keyInfoResult as? KeyInfoResult.Success)?.keyInfo
                 ?: return IntegrityResult.Error(SharedSecretStorageError.UnknownKey(keyId ?: ""))
 
-        if (keyInfo.content.algorithm != SSSS_ALGORITHM_AES_HMAC_SHA2 &&
+        if (keyInfo.content.algorithm != SSSS_ALGORITHM_AES_HMAC_SHA2) {
-                keyInfo.content.algorithm != SSSS_ALGORITHM_CURVE25519_AES_SHA2) {
             // Unsupported algorithm
             return IntegrityResult.Error(
                     SharedSecretStorageError.UnsupportedAlgorithm(keyInfo.content.algorithm ?: "")