Determine MBEDTLS_ECP_MAX_BITS automatically
MBEDTLS_ECP_MAX_BITS is now determined automatically from the configured
curves and no longer needs to be configured explicitly to save RAM. Setting
it explicit in config.h is still supported for backward compatibility.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/configs/config-suite-b.h b/configs/config-suite-b.h
index 6eb03a9..9cad382 100644
--- a/configs/config-suite-b.h
+++ b/configs/config-suite-b.h
@@ -80,8 +80,7 @@
#define MBEDTLS_AES_ROM_TABLES
/* Save RAM by adjusting to our exact needs */
-#define MBEDTLS_ECP_MAX_BITS 384
-#define MBEDTLS_MPI_MAX_SIZE 48 // 384 bits is 48 bytes
+#define MBEDTLS_MPI_MAX_SIZE 48 // 48 bytes for a 384-bit elliptic curve
/* Save RAM at the expense of speed, see ecp.h */
#define MBEDTLS_ECP_WINDOW_SIZE 2
diff --git a/configs/config-thread.h b/configs/config-thread.h
index 47dd5e2..8464fcb 100644
--- a/configs/config-thread.h
+++ b/configs/config-thread.h
@@ -81,8 +81,7 @@
#define MBEDTLS_AES_ROM_TABLES
/* Save RAM by adjusting to our exact needs */
-#define MBEDTLS_ECP_MAX_BITS 256
-#define MBEDTLS_MPI_MAX_SIZE 32 // 256 bits is 32 bytes
+#define MBEDTLS_MPI_MAX_SIZE 32 // 32 bytes for a 256-bit elliptic curve
/* Save ROM and a few bytes of RAM by specifying our own ciphersuite list */
#define MBEDTLS_SSL_CIPHERSUITES MBEDTLS_TLS_ECJPAKE_WITH_AES_128_CCM_8