diff --git a/include/polarssl/cipher.h b/include/polarssl/cipher.h
index 67ca28c..ef037be 100644
--- a/include/polarssl/cipher.h
+++ b/include/polarssl/cipher.h
@@ -320,7 +320,7 @@
  * \param ctx           cipher's context. Must have been initialised.
  *
  * \return              size of the cipher's IV, or 0 if ctx has not been
- *                      initialised.
+ *                      initialised or accepts IV of various sizes.
  */
 static inline int cipher_get_iv_size( const cipher_context_t *ctx )
 {
@@ -432,11 +432,18 @@
  *
  * \param ctx           generic cipher context
  * \param iv            IV to use or NONCE_COUNTER in the case of a CTR-mode cipher
+ * \param iv_len        IV length for ciphers with variable-size IV,
+ *                      Discared by ciphers with fixed-size IV.
+ * \param ad            Additional data for AEAD ciphers, or discarded.
+ *                      May be NULL only if ad_len is 0.
+ * \param ad_len        Length of ad for AEAD ciphers, or discarded.
  *
  * \returns             0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA
  *                      if parameter verification fails.
  */
-int cipher_reset( cipher_context_t *ctx, const unsigned char *iv );
+int cipher_reset( cipher_context_t *ctx,
+                  const unsigned char *iv, size_t iv_len,
+                  const unsigned char *ad, size_t ad_len );
 
 /**
  * \brief               Generic cipher update function. Encrypts/decrypts
@@ -471,8 +478,13 @@
  *                      the last block, and written to the output buffer.
  *
  * \param ctx           Generic cipher context
- * \param output        buffer to write data to. Needs block_size data available.
+ * \param output        buffer to write data to. Needs block_size available.
  * \param olen          length of the data written to the output buffer.
+ * \param tag           Ignore by non-AEAD ciphers. For AEAD ciphers:
+ *                      - on encryption: buffer to write the tag;
+ *                      - on decryption: tag to verify.
+ *                      May be NULL if tag_len is zero.
+ * \param tag_len       Length of the tag to write/check for AEAD ciphers.
  *
  * \returns             0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if
  *                      parameter verification fails,
@@ -481,7 +493,9 @@
  *                      POLARSSL_ERR_CIPHER_INVALID_PADDING on invalid padding
  *                      while decrypting or a cipher specific error code.
  */
-int cipher_finish( cipher_context_t *ctx, unsigned char *output, size_t *olen);
+int cipher_finish( cipher_context_t *ctx,
+                   unsigned char *output, size_t *olen,
+                   unsigned char *tag, size_t tag_len );
 
 /**
  * \brief          Checkup routine