cryptodev: add comments for DOCSIS protocol

Add a note to the rte_crypto_sym_op->auth.data fields to state that
for DOCSIS security protocol, these are used to specify the offset and
length of data over which the CRC is calculated.

Signed-off-by: David Coyle <david.coyle@intel.com>
Signed-off-by: Mairtin o Loingsigh <mairtin.oloingsigh@intel.com>
Acked-by: Akhil Goyal <akhil.goyal@nxp.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>

diff --git a/lib/librte_cryptodev/rte_crypto_sym.h b/lib/librte_cryptodev/rte_crypto_sym.h
index da961a1..f29c980 100644 (file)
--- a/lib/librte_cryptodev/rte_crypto_sym.h
+++ b/lib/librte_cryptodev/rte_crypto_sym.h
@@ -705,6 +705,14 @@ struct rte_crypto_sym_op {
                                          * For KASUMI @ RTE_CRYPTO_AUTH_KASUMI_F9,
                                          * this offset should be such that
                                          * data to authenticate starts at COUNT.
+                                         *
+                                         * @note
+                                         * For DOCSIS security protocol, this
+                                         * offset is the DOCSIS header length
+                                         * and, therefore, also the CRC offset
+                                         * i.e. the number of bytes into the
+                                         * packet at which CRC calculation
+                                         * should begin.
                                          */
                                        uint32_t length;
                                         /**< The message length, in bytes, of the source
@@ -723,6 +731,12 @@ struct rte_crypto_sym_op {
                                          * the length should include the COUNT,
                                          * FRESH, message, direction bit and padding
                                          * (to be multiple of 8 bits).
+                                         *
+                                         * @note
+                                         * For DOCSIS security protocol, this
+                                         * is the CRC length i.e. the number of
+                                         * bytes in the packet over which the
+                                         * CRC should be calculated
                                          */
                                } data;
                                /**< Data offsets and length for authentication */