[PATCH 1/4] rkimage: Support openssl provider API

[Sascha Hauer <s.hauer@pengutronix.de>]

openssl engine support has long been deprecated. Add provider support.
engine support is still needed in some cases, so first try provider
support and fall back to engine support if necessary.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 scripts/rkimage.c | 40 ++++++++++++++++++++++++++++++++++------
 1 file changed, 34 insertions(+), 6 deletions(-)

diff --git a/scripts/rkimage.c b/scripts/rkimage.c
index e5b6d61c4a..04d98daa6d 100644
--- a/scripts/rkimage.c
+++ b/scripts/rkimage.c
@@ -13,15 +13,13 @@
 #include <stdbool.h>
 
 #include <openssl/bn.h>
-/*
- * TODO Switch from the OpenSSL ENGINE API to the PKCS#11 provider and the
- * PROVIDER API: https://github.com/latchset/pkcs11-provider
- */
+#include <openssl/err.h>
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #include <openssl/engine.h>
 #include <openssl/evp.h>
 #include <openssl/pem.h>
 #include <openssl/rsa.h>
+#include <openssl/store.h>
 
 #include "common.h"
 #include "common.c"
@@ -63,12 +61,42 @@ static void idb_hash(struct newidb *idb)
 		sha512(idbu8, size, idbu8 + size);
 }
 
-static __attribute__((unused)) EVP_PKEY *load_key_pkcs11(const char *path)
+static __attribute__((unused)) EVP_PKEY *load_key_pkcs11(const char *uri)
 {
+	OSSL_STORE_CTX *ctx;
+	OSSL_STORE_INFO *info;
 	const char *engine_id = "pkcs11";
 	ENGINE *e;
 	EVP_PKEY *pkey = NULL;
 
+	/* Try provider-based store first (requires pkcs11-provider) */
+	ctx = OSSL_STORE_open(uri, NULL, NULL, NULL, NULL);
+	if (ctx) {
+		while (!OSSL_STORE_eof(ctx)) {
+			info = OSSL_STORE_load(ctx);
+			if (!info)
+				break;
+			if (OSSL_STORE_INFO_get_type(info) ==
+			    OSSL_STORE_INFO_PKEY) {
+				pkey = OSSL_STORE_INFO_get1_PKEY(info);
+				OSSL_STORE_INFO_free(info);
+				break;
+			}
+			OSSL_STORE_INFO_free(info);
+		}
+		OSSL_STORE_close(ctx);
+		if (pkey)
+			return pkey;
+	}
+
+	/*
+	 * Fall back to legacy ENGINE API (requires libp11 pkcs11 engine).
+	 * The provider-based approach above requires pkcs11-provider, which is
+	 * not yet available in ptxdist environments. The deprecated ENGINE API
+	 * via libp11 remains functional there and is used as a fallback.
+	 */
+	ERR_clear_error();
+
 	ENGINE_load_builtin_engines();
 
 	e = ENGINE_by_id(engine_id);
@@ -81,7 +109,7 @@ static __attribute__((unused)) EVP_PKEY *load_key_pkcs11(const char *path)
 		goto err_engine_init;
 	}
 
-	pkey = ENGINE_load_private_key(e, path, NULL, NULL);
+	pkey = ENGINE_load_private_key(e, uri, NULL, NULL);
 
 	ENGINE_finish(e);
 err_engine_init:

-- 
2.47.3