Add ecp_tls_write_group()
diff --git a/include/polarssl/ecp.h b/include/polarssl/ecp.h
index a810a62..0919cbe 100644
--- a/include/polarssl/ecp.h
+++ b/include/polarssl/ecp.h
@@ -53,6 +53,11 @@
}
ecp_point;
+/*
+ * RFC 4492 defines an enum NamedCurve with two-bytes values
+ */
+typedef uint16_t ecp_group_id;
+
/**
* \brief ECP group structure
*
@@ -70,6 +75,7 @@
*/
typedef struct
{
+ ecp_group_id id; /*!< RFC 4492 group ID */
mpi P; /*!< prime modulus of the base field */
mpi B; /*!< constant term in the equation */
ecp_point G; /*!< generator of the subgroup used */
@@ -284,7 +290,7 @@
* \note Index should be a value of RFC 4492's enum NamdeCurve,
* possibly in the form of a POLARSSL_ECP_DP_XXX macro.
*/
-int ecp_use_known_dp( ecp_group *grp, uint16_t index );
+int ecp_use_known_dp( ecp_group *grp, ecp_group_id id );
/**
* \brief Set a group from a TLS ECParameters record
@@ -300,6 +306,20 @@
int ecp_tls_read_group( ecp_group *grp, const unsigned char *buf, size_t len );
/**
+ * \brief Write the TLS ECParameters record for a group
+ *
+ * \param grp ECP group used
+ * \param olen Number of bytes actually written
+ * \param buf Buffer to write to
+ * \param blen Buffer length
+ *
+ * \return 0 if successful,
+ * or POLARSSL_ERR_ECP_BUFFER_TOO_SMALL
+ */
+int ecp_tls_write_group( const ecp_group *grp, size_t *olen,
+ unsigned char *buf, size_t blen );
+
+/**
* \brief Import a point from a TLS ECPoint record
*
* \param grp ECP group used