diff --git a/include/mbedtls/cmac.h b/include/mbedtls/cmac.h
index 1cac948..628c9da 100644
--- a/include/mbedtls/cmac.h
+++ b/include/mbedtls/cmac.h
@@ -1,11 +1,11 @@
 /**
  * \file cmac.h
  *
- * \brief Cipher-based Message Authentication Code (CMAC) Mode for
- *        Authentication
+ * \brief The Cipher-based Message Authentication Code (CMAC) Mode for
+ *        Authentication.
  */
 /*
- *  Copyright (C) 2015-2016, ARM Limited, All Rights Reserved
+ *  Copyright (C) 2015-2018, Arm Limited (or its affiliates), All Rights Reserved
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -20,8 +20,9 @@
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  *
- *  This file is part of mbed TLS (https://tls.mbed.org)
+ *  This file is part of Mbed TLS (https://tls.mbed.org)
  */
+
 #ifndef MBEDTLS_CMAC_H
 #define MBEDTLS_CMAC_H
 
@@ -31,110 +32,125 @@
 extern "C" {
 #endif
 
-#define MBEDTLS_ERR_CMAC_HW_ACCEL_FAILED                  -0x007A  /**< CMAC hardware accelerator failed. */
+#define MBEDTLS_ERR_CMAC_HW_ACCEL_FAILED -0x007A  /**< CMAC hardware accelerator failed. */
 
 #define MBEDTLS_AES_BLOCK_SIZE          16
 #define MBEDTLS_DES3_BLOCK_SIZE         8
 
 #if defined(MBEDTLS_AES_C)
-#define MBEDTLS_CIPHER_BLKSIZE_MAX      16  /* longest used by CMAC is AES */
+#define MBEDTLS_CIPHER_BLKSIZE_MAX      16  /* The longest block used by CMAC is that of AES. */
 #else
-#define MBEDTLS_CIPHER_BLKSIZE_MAX      8   /* longest used by CMAC is 3DES */
+#define MBEDTLS_CIPHER_BLKSIZE_MAX      8   /* The longest block used by CMAC is that of 3DES. */
 #endif
 
 #if !defined(MBEDTLS_CMAC_ALT)
 
 /**
- * CMAC context structure - Contains internal state information only
+ * The CMAC context structure.
  */
 struct mbedtls_cmac_context_t
 {
-    /** Internal state of the CMAC algorithm  */
+    /** The internal state of the CMAC algorithm.  */
     unsigned char       state[MBEDTLS_CIPHER_BLKSIZE_MAX];
 
     /** Unprocessed data - either data that was not block aligned and is still
-     *  pending to be processed, or the final block */
+     *  pending processing, or the final block. */
     unsigned char       unprocessed_block[MBEDTLS_CIPHER_BLKSIZE_MAX];
 
-    /** Length of data pending to be processed */
+    /** The length of data pending processing. */
     size_t              unprocessed_len;
 };
 
 /**
- * \brief               Set the CMAC key and prepare to authenticate the input
- *                      data.
- *                      Should be called with an initialized cipher context.
+ * \brief               This function sets the CMAC key, and prepares to authenticate
+ *                      the input data.
+ *                      Must be called with an initialized cipher context.
  *
- * \param ctx           Cipher context. This should be a cipher context,
- *                      initialized to be one of the following types:
- *                      MBEDTLS_CIPHER_AES_128_ECB, MBEDTLS_CIPHER_AES_192_ECB,
- *                      MBEDTLS_CIPHER_AES_256_ECB or
- *                      MBEDTLS_CIPHER_DES_EDE3_ECB.
- * \param key           CMAC key
- * \param keybits       length of the CMAC key in bits
- *                      (must be acceptable by the cipher)
+ * \param ctx           The cipher context used for the CMAC operation, initialized
+ *                      as one of the following types:<ul>
+ *                      <li>MBEDTLS_CIPHER_AES_128_ECB</li>
+ *                      <li>MBEDTLS_CIPHER_AES_192_ECB</li>
+ *                      <li>MBEDTLS_CIPHER_AES_256_ECB</li>
+ *                      <li>MBEDTLS_CIPHER_DES_EDE3_ECB</li></ul>
+ * \param key           The CMAC key.
+ * \param keybits       The length of the CMAC key in bits.
+ *                      Must be supported by the cipher.
  *
- * \return              0 if successful, or a cipher specific error code
+ * \return              \c 0 on success, or a cipher-specific error code.
  */
 int mbedtls_cipher_cmac_starts( mbedtls_cipher_context_t *ctx,
                                 const unsigned char *key, size_t keybits );
 
 /**
- * \brief               Generic CMAC process buffer.
- *                      Called between mbedtls_cipher_cmac_starts() or
- *                      mbedtls_cipher_cmac_reset() and
- *                      mbedtls_cipher_cmac_finish().
- *                      May be called repeatedly.
+ * \brief               This function feeds an input buffer into an ongoing CMAC
+ *                      computation.
  *
- * \param ctx           CMAC context
- * \param input         buffer holding the  data
- * \param ilen          length of the input data
+ *                      It is called between mbedtls_cipher_cmac_starts() or
+ *                      mbedtls_cipher_cmac_reset(), and mbedtls_cipher_cmac_finish().
+ *                      Can be called repeatedly.
  *
- * \returns             0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
- *                      verification fails.
+ * \param ctx           The cipher context used for the CMAC operation.
+ * \param input         The buffer holding the input data.
+ * \param ilen          The length of the input data.
+ *
+ * \returns             \c 0 on success, or #MBEDTLS_ERR_MD_BAD_INPUT_DATA
+ *                      if parameter verification fails.
  */
 int mbedtls_cipher_cmac_update( mbedtls_cipher_context_t *ctx,
                                 const unsigned char *input, size_t ilen );
 
 /**
- * \brief               Output CMAC.
- *                      Called after mbedtls_cipher_cmac_update().
- *                      Usually followed by mbedtls_cipher_cmac_reset(), then
- *                      mbedtls_cipher_cmac_starts(), or mbedtls_cipher_free().
+ * \brief               This function finishes the CMAC operation, and writes
+ *                      the result to the output buffer.
  *
- * \param ctx           CMAC context
- * \param output        Generic CMAC checksum result
+ *                      It is called after mbedtls_cipher_cmac_update().
+ *                      It can be followed by mbedtls_cipher_cmac_reset() and
+ *                      mbedtls_cipher_cmac_update(), or mbedtls_cipher_free().
  *
- * \returns             0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
- *                      verification fails.
+ * \param ctx           The cipher context used for the CMAC operation.
+ * \param output        The output buffer for the CMAC checksum result.
+ *
+ * \returns             \c 0 on success, or #MBEDTLS_ERR_MD_BAD_INPUT_DATA
+ *                      if parameter verification fails.
  */
 int mbedtls_cipher_cmac_finish( mbedtls_cipher_context_t *ctx,
                                 unsigned char *output );
 
 /**
- * \brief               Prepare to authenticate a new message with the same key.
- *                      Called after mbedtls_cipher_cmac_finish() and before
- *                      mbedtls_cipher_cmac_update().
+ * \brief               This function prepares the authentication of another
+ *                      message with the same key as the previous CMAC
+ *                      operation.
  *
- * \param ctx           CMAC context to be reset
+ *                      It is called after mbedtls_cipher_cmac_finish()
+ *                      and before mbedtls_cipher_cmac_update().
  *
- * \returns             0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
- *                      verification fails.
+ * \param ctx           The cipher context used for the CMAC operation.
+ *
+ * \returns             \c 0 on success, or #MBEDTLS_ERR_MD_BAD_INPUT_DATA
+ *                      if parameter verification fails.
  */
 int mbedtls_cipher_cmac_reset( mbedtls_cipher_context_t *ctx );
 
 /**
- * \brief               Output = Generic_CMAC( cmac key, input buffer )
+ * \brief               This function calculates the full generic CMAC
+ *                      on the input buffer with the provided key.
  *
- * \param cipher_info   message digest info
- * \param key           CMAC key
- * \param keylen        length of the CMAC key in bits
- * \param input         buffer holding the  data
- * \param ilen          length of the input data
- * \param output        Generic CMAC-result
+ *                      The function allocates the context, performs the
+ *                      calculation, and frees the context.
  *
- * \returns             0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
- *                      verification fails.
+ *                      The CMAC result is calculated as
+ *                      output = generic CMAC(cmac key, input buffer).
+ *
+ *
+ * \param cipher_info   The cipher information.
+ * \param key           The CMAC key.
+ * \param keylen        The length of the CMAC key in bits.
+ * \param input         The buffer holding the input data.
+ * \param ilen          The length of the input data.
+ * \param output        The buffer for the generic CMAC result.
+ *
+ * \returns             \c 0 on success, or #MBEDTLS_ERR_MD_BAD_INPUT_DATA
+ *                      if parameter verification fails.
  */
 int mbedtls_cipher_cmac( const mbedtls_cipher_info_t *cipher_info,
                          const unsigned char *key, size_t keylen,
@@ -143,16 +159,21 @@
 
 #if defined(MBEDTLS_AES_C)
 /**
- * \brief           AES-CMAC-128-PRF
- *                  Implementation of (AES-CMAC-PRF-128), as defined in RFC 4615
+ * \brief           This function implements the AES-CMAC-PRF-128 pseudorandom
+ *                  function, as defined in
+ *                  <em>RFC-4615: The Advanced Encryption Standard-Cipher-based
+ *                  Message Authentication Code-Pseudo-Random Function-128
+ *                  (AES-CMAC-PRF-128) Algorithm for the Internet Key
+ *                  Exchange Protocol (IKE).</em>
  *
- * \param key       PRF key
- * \param key_len   PRF key length in bytes
- * \param input     buffer holding the input data
- * \param in_len    length of the input data in bytes
- * \param output    buffer holding the generated pseudorandom output (16 bytes)
+ * \param key       The key to use.
+ * \param key_len   The key length in Bytes.
+ * \param input     The buffer holding the input data.
+ * \param in_len    The length of the input data in Bytes.
+ * \param output    The buffer holding the generated 16 Bytes of
+ *                  pseudorandom output.
  *
- * \return          0 if successful
+ * \return          \c 0 on success.
  */
 int mbedtls_aes_cmac_prf_128( const unsigned char *key, size_t key_len,
                               const unsigned char *input, size_t in_len,
@@ -173,9 +194,9 @@
 
 #if defined(MBEDTLS_SELF_TEST) && ( defined(MBEDTLS_AES_C) || defined(MBEDTLS_DES_C) )
 /**
- * \brief          Checkup routine
+ * \brief          The CMAC checkup routine.
  *
- * \return         0 if successful, or 1 if the test failed
+ * \return         \c 0 on success, or \c 1 on failure.
  */
 int mbedtls_cmac_self_test( int verbose );
 #endif /* MBEDTLS_SELF_TEST && ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */