Fix mbedtls_ecdh_get_params with new ECDH context
The new check for matching groups in mbedtls_ecdh_get_params only worked
with legacy ECDH contexts. Make it work with the new context format.
diff --git a/library/ecdh.c b/library/ecdh.c
index 204a278..c572687 100644
--- a/library/ecdh.c
+++ b/library/ecdh.c
@@ -49,6 +49,16 @@
typedef mbedtls_ecdh_context mbedtls_ecdh_context_mbed;
#endif
+static mbedtls_ecp_group_id mbedtls_ecdh_grp_id(
+ const mbedtls_ecdh_context *ctx )
+{
+#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT)
+ return( ctx->grp.id );
+#else
+ return( ctx->grp_id );
+#endif
+}
+
#if !defined(MBEDTLS_ECDH_GEN_PUBLIC_ALT)
/*
* Generate public key (restartable version)
@@ -442,7 +452,7 @@
ECDH_VALIDATE_RET( side == MBEDTLS_ECDH_OURS ||
side == MBEDTLS_ECDH_THEIRS );
- if( ctx->grp.id == MBEDTLS_ECP_DP_NONE )
+ if( mbedtls_ecdh_grp_id( ctx ) == MBEDTLS_ECP_DP_NONE )
{
/* This is the first call to get_params(). Set up the context
* for use with the group. */
@@ -454,7 +464,7 @@
/* This is not the first call to get_params(). Check that the
* current key's group is the same as the context's, which was set
* from the first key's group. */
- if( ctx->grp.id != key->grp.id )
+ if( mbedtls_ecdh_grp_id( ctx ) != key->grp.id )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
}