diff --git a/library/psa_crypto_cipher.c b/library/psa_crypto_cipher.c
index d6ad902..73a2dab 100644
--- a/library/psa_crypto_cipher.c
+++ b/library/psa_crypto_cipher.c
@@ -23,5 +23,124 @@
 #if defined(MBEDTLS_PSA_CRYPTO_C)
 
 #include <psa_crypto_cipher.h>
+#include "psa_crypto_core.h"
+#include "mbedtls/cipher.h"
 
+#include <string.h>
+
+static psa_status_t cipher_setup(
+    psa_cipher_operation_t *operation,
+    const psa_key_attributes_t *attributes,
+    const uint8_t *key_buffer, size_t key_buffer_size,
+    psa_algorithm_t alg,
+    mbedtls_operation_t cipher_operation )
+{
+    int ret = 0;
+    size_t key_bits;
+    const mbedtls_cipher_info_t *cipher_info = NULL;
+    psa_key_type_t key_type = attributes->core.type;
+
+    (void)key_buffer_size;
+
+    /* Proceed with initializing an mbed TLS cipher context if no driver is
+     * available for the given algorithm & key. */
+    mbedtls_cipher_init( &operation->ctx.cipher );
+
+    /* Once the cipher context is initialised, it needs to be freed using
+     * psa_cipher_abort. Indicate there is something to be freed through setting
+     * alg, and indicate the operation is being done using mbedtls crypto through
+     * setting mbedtls_in_use. */
+    operation->alg = alg;
+    operation->mbedtls_in_use = 1;
+
+    key_bits = attributes->core.bits;
+    cipher_info = mbedtls_cipher_info_from_psa( alg, key_type,
+                                                key_bits, NULL );
+    if( cipher_info == NULL )
+        return( PSA_ERROR_NOT_SUPPORTED );
+
+    ret = mbedtls_cipher_setup( &operation->ctx.cipher, cipher_info );
+    if( ret != 0 )
+        goto exit;
+
+#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES)
+    if( key_type == PSA_KEY_TYPE_DES && key_bits == 128 )
+    {
+        /* Two-key Triple-DES is 3-key Triple-DES with K1=K3 */
+        uint8_t keys[24];
+        memcpy( keys, key_buffer, 16 );
+        memcpy( keys + 16, key_buffer, 8 );
+        ret = mbedtls_cipher_setkey( &operation->ctx.cipher,
+                                     keys,
+                                     192, cipher_operation );
+    }
+    else
+#endif
+    {
+        ret = mbedtls_cipher_setkey( &operation->ctx.cipher, key_buffer,
+                                     (int) key_bits, cipher_operation );
+    }
+    if( ret != 0 )
+        goto exit;
+
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_NO_PADDING) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_PKCS7)
+    switch( alg )
+    {
+        case PSA_ALG_CBC_NO_PADDING:
+            ret = mbedtls_cipher_set_padding_mode( &operation->ctx.cipher,
+                                                   MBEDTLS_PADDING_NONE );
+            break;
+        case PSA_ALG_CBC_PKCS7:
+            ret = mbedtls_cipher_set_padding_mode( &operation->ctx.cipher,
+                                                   MBEDTLS_PADDING_PKCS7 );
+            break;
+        default:
+            /* The algorithm doesn't involve padding. */
+            ret = 0;
+            break;
+    }
+    if( ret != 0 )
+        goto exit;
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CBC_NO_PADDING || MBEDTLS_PSA_BUILTIN_ALG_CBC_PKCS7 */
+
+    operation->block_size = ( PSA_ALG_IS_STREAM_CIPHER( alg ) ? 1 :
+                              PSA_BLOCK_CIPHER_BLOCK_LENGTH( key_type ) );
+    if( ( alg & PSA_ALG_CIPHER_FROM_BLOCK_FLAG ) != 0 &&
+        alg != PSA_ALG_ECB_NO_PADDING )
+    {
+        operation->iv_size = PSA_BLOCK_CIPHER_BLOCK_LENGTH( key_type );
+    }
+#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_CHACHA20)
+    else
+    if( ( alg == PSA_ALG_STREAM_CIPHER ) &&
+        ( key_type == PSA_KEY_TYPE_CHACHA20 ) )
+        operation->iv_size = 12;
+#endif
+
+exit:
+    return( mbedtls_to_psa_error( ret ) );
+}
+
+psa_status_t mbedtls_psa_cipher_encrypt_setup(
+    psa_cipher_operation_t *operation,
+    const psa_key_attributes_t *attributes,
+    const uint8_t *key_buffer, size_t key_buffer_size,
+    psa_algorithm_t alg )
+{
+    return( cipher_setup( operation, attributes,
+                          key_buffer, key_buffer_size,
+                          alg, MBEDTLS_ENCRYPT ) );
+}
+
+psa_status_t mbedtls_psa_cipher_decrypt_setup(
+    psa_cipher_operation_t *operation,
+    const psa_key_attributes_t *attributes,
+    const uint8_t *key_buffer, size_t key_buffer_size,
+    psa_algorithm_t alg )
+{
+    return( cipher_setup( operation, attributes,
+                          key_buffer, key_buffer_size,
+                          alg, MBEDTLS_DECRYPT ) );
+}
 #endif /* MBEDTLS_PSA_CRYPTO_C */