CCM*: Add public API
Interface for CCM* (described in IEEE Std 802.15.4.).
diff --git a/include/mbedtls/ccm.h b/include/mbedtls/ccm.h
index 8585ce5..24e13dd 100644
--- a/include/mbedtls/ccm.h
+++ b/include/mbedtls/ccm.h
@@ -102,7 +102,6 @@
/**
* \brief This function encrypts a buffer using CCM.
*
- *
* \note The tag is written to a separate buffer. To concatenate
* the \p tag with the \p output, as done in <em>RFC-3610:
* Counter with CBC-MAC (CCM)</em>, use
@@ -133,6 +132,45 @@
unsigned char *tag, size_t tag_len );
/**
+ * \brief This function encrypts a buffer using CCM*.
+ *
+ * \note The tag is written to a separate buffer. To concatenate
+ * the \p tag with the \p output, as done in <em>RFC-3610:
+ * Counter with CBC-MAC (CCM)</em>, use
+ * \p tag = \p output + \p length, and make sure that the
+ * output buffer is at least \p length + \p tag_len wide.
+ *
+ * \note When using this function in a variable tag length context,
+ * the tag length has to be encoded into the \p iv passed to
+ * this function.
+ *
+ * \param ctx The CCM context to use for encryption.
+ * \param length The length of the input data in Bytes.
+ * \param iv Initialization vector (nonce).
+ * \param iv_len The length of the IV in Bytes: 7, 8, 9, 10, 11, 12, or 13.
+ * \param add The additional data field.
+ * \param add_len The length of additional data in Bytes.
+ * Must be less than 2^16 - 2^8.
+ * \param input The buffer holding the input data.
+ * \param output The buffer holding the output data.
+ * Must be at least \p length Bytes wide.
+ * \param tag The buffer holding the tag.
+ * \param tag_len The length of the tag to generate in Bytes:
+ * 0, 4, 6, 8, 10, 12, 14 or 16.
+ *
+ * \warning Passing 0 as \p tag_len means that the message is no
+ * longer authenticated.
+ *
+ * \return \c 0 on success.
+ * \return A CCM or cipher-specific error code on failure.
+ */
+int mbedtls_ccm_star_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
+ const unsigned char *iv, size_t iv_len,
+ const unsigned char *add, size_t add_len,
+ const unsigned char *input, unsigned char *output,
+ unsigned char *tag, size_t tag_len );
+
+/**
* \brief This function performs a CCM authenticated decryption of a
* buffer.
*
@@ -160,6 +198,42 @@
const unsigned char *input, unsigned char *output,
const unsigned char *tag, size_t tag_len );
+/**
+ * \brief This function performs a CCM* authenticated decryption of a
+ * buffer.
+ *
+ * \note When using this function in a variable tag length context,
+ * the tag length has to be decoded from \p iv and passed to
+ * this function as \p tag_len. (\p tag needs to be adjusted
+ * accordingly.)
+ *
+ * \param ctx The CCM context to use for decryption.
+ * \param length The length of the input data in Bytes.
+ * \param iv Initialization vector.
+ * \param iv_len The length of the IV in Bytes: 7, 8, 9, 10, 11, 12, or 13.
+ * \param add The additional data field.
+ * \param add_len The length of additional data in Bytes.
+ * Must be less than 2^16 - 2^8.
+ * \param input The buffer holding the input data.
+ * \param output The buffer holding the output data.
+ * Must be at least \p length Bytes wide.
+ * \param tag The buffer holding the tag.
+ * \param tag_len The length of the tag in Bytes.
+ * 0, 4, 6, 8, 10, 12, 14 or 16.
+ *
+ * \warning Passing 0 as \p tag_len means that the message is no
+ * longer authenticated.
+ *
+ * \return \c 0 on success. This indicates that the message is
+ * authentic.
+ * \return #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not match.
+ * \return A cipher-specific error code on calculation failure.
+ */
+int mbedtls_ccm_star_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
+ const unsigned char *iv, size_t iv_len,
+ const unsigned char *add, size_t add_len,
+ const unsigned char *input, unsigned char *output,
+ const unsigned char *tag, size_t tag_len );
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
/**
