pkwrite: add opaque key handling for public key exporting
Return early from mbedtls_pk_write_pubkey_der - public opaque key
exporting is expected to contain all of the needed data, therefore it shouldn't
be written again.
diff --git a/library/pkwrite.c b/library/pkwrite.c
index 8eabd88..d135060 100644
--- a/library/pkwrite.c
+++ b/library/pkwrite.c
@@ -46,6 +46,9 @@
#include "mbedtls/pem.h"
#endif
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+#include "psa/crypto.h"
+#endif
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
@@ -161,6 +164,23 @@
MBEDTLS_ASN1_CHK_ADD( len, pk_write_ec_pubkey( p, start, mbedtls_pk_ec( *key ) ) );
else
#endif
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+ if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_OPAQUE )
+ {
+ size_t buffer_size = *p - start;
+ psa_key_slot_t* key_slot = ( psa_key_slot_t* ) key->pk_ctx;
+ if ( psa_export_public_key( *key_slot, start, buffer_size, &len )
+ != PSA_SUCCESS )
+ {
+ return MBEDTLS_ERR_PK_BAD_INPUT_DATA;
+ }
+ else
+ {
+ memmove( *p - len, start, len );
+ }
+ }
+ else
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
return( (int) len );
@@ -177,6 +197,10 @@
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_pk_write_pubkey( &c, buf, key ) );
+ if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_OPAQUE )
+ {
+ return( (int) len );
+ }
if( c - buf < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );