Fix ecp_tls_read_group's signature
diff --git a/include/polarssl/ecp.h b/include/polarssl/ecp.h
index 373de8d..ec9067d 100644
--- a/include/polarssl/ecp.h
+++ b/include/polarssl/ecp.h
@@ -296,14 +296,14 @@
* \brief Set a group from a TLS ECParameters record
*
* \param grp Destination group
- * \param buf Start of input buffer
+ * \param buf &(Start of input buffer)
* \param len Buffer length
*
* \return O if successful,
* POLARSSL_ERR_MPI_XXX if initialization failed
* POLARSSL_ERR_ECP_BAD_INPUT_DATA if input is invalid
*/
-int ecp_tls_read_group( ecp_group *grp, const unsigned char *buf, size_t len );
+int ecp_tls_read_group( ecp_group *grp, const unsigned char **buf, size_t len );
/**
* \brief Write the TLS ECParameters record for a group