diff --git a/library/psa_crypto_cipher.c b/library/psa_crypto_cipher.c
index ca91eaa..5440e45 100644
--- a/library/psa_crypto_cipher.c
+++ b/library/psa_crypto_cipher.c
@@ -55,6 +55,98 @@
 #define BUILTIN_KEY_TYPE_CHACHA20  1
 #endif
 
+const mbedtls_cipher_info_t *mbedtls_cipher_info_from_psa(
+    psa_algorithm_t alg,
+    psa_key_type_t key_type,
+    size_t key_bits,
+    mbedtls_cipher_id_t* cipher_id )
+{
+    mbedtls_cipher_mode_t mode;
+    mbedtls_cipher_id_t cipher_id_tmp;
+
+    if( PSA_ALG_IS_AEAD( alg ) )
+        alg = PSA_ALG_AEAD_WITH_SHORTENED_TAG( alg, 0 );
+
+    if( PSA_ALG_IS_CIPHER( alg ) || PSA_ALG_IS_AEAD( alg ) )
+    {
+        switch( alg )
+        {
+            case PSA_ALG_STREAM_CIPHER:
+                mode = MBEDTLS_MODE_STREAM;
+                break;
+            case PSA_ALG_CTR:
+                mode = MBEDTLS_MODE_CTR;
+                break;
+            case PSA_ALG_CFB:
+                mode = MBEDTLS_MODE_CFB;
+                break;
+            case PSA_ALG_OFB:
+                mode = MBEDTLS_MODE_OFB;
+                break;
+            case PSA_ALG_ECB_NO_PADDING:
+                mode = MBEDTLS_MODE_ECB;
+                break;
+            case PSA_ALG_CBC_NO_PADDING:
+                mode = MBEDTLS_MODE_CBC;
+                break;
+            case PSA_ALG_CBC_PKCS7:
+                mode = MBEDTLS_MODE_CBC;
+                break;
+            case PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_CCM, 0 ):
+                mode = MBEDTLS_MODE_CCM;
+                break;
+            case PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_GCM, 0 ):
+                mode = MBEDTLS_MODE_GCM;
+                break;
+            case PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_CHACHA20_POLY1305, 0 ):
+                mode = MBEDTLS_MODE_CHACHAPOLY;
+                break;
+            default:
+                return( NULL );
+        }
+    }
+    else if( alg == PSA_ALG_CMAC )
+        mode = MBEDTLS_MODE_ECB;
+    else
+        return( NULL );
+
+    switch( key_type )
+    {
+        case PSA_KEY_TYPE_AES:
+            cipher_id_tmp = MBEDTLS_CIPHER_ID_AES;
+            break;
+        case PSA_KEY_TYPE_DES:
+            /* key_bits is 64 for Single-DES, 128 for two-key Triple-DES,
+             * and 192 for three-key Triple-DES. */
+            if( key_bits == 64 )
+                cipher_id_tmp = MBEDTLS_CIPHER_ID_DES;
+            else
+                cipher_id_tmp = MBEDTLS_CIPHER_ID_3DES;
+            /* mbedtls doesn't recognize two-key Triple-DES as an algorithm,
+             * but two-key Triple-DES is functionally three-key Triple-DES
+             * with K1=K3, so that's how we present it to mbedtls. */
+            if( key_bits == 128 )
+                key_bits = 192;
+            break;
+        case PSA_KEY_TYPE_CAMELLIA:
+            cipher_id_tmp = MBEDTLS_CIPHER_ID_CAMELLIA;
+            break;
+        case PSA_KEY_TYPE_ARC4:
+            cipher_id_tmp = MBEDTLS_CIPHER_ID_ARC4;
+            break;
+        case PSA_KEY_TYPE_CHACHA20:
+            cipher_id_tmp = MBEDTLS_CIPHER_ID_CHACHA20;
+            break;
+        default:
+            return( NULL );
+    }
+    if( cipher_id != NULL )
+        *cipher_id = cipher_id_tmp;
+
+    return( mbedtls_cipher_info_from_values( cipher_id_tmp,
+                                             (int) key_bits, mode ) );
+}
+
 #if defined(MBEDTLS_PSA_BUILTIN_CIPHER) || defined(PSA_CRYPTO_DRIVER_TEST)
 
 static psa_status_t cipher_setup(