Allow to pass a passprase callback at store open

Some PKCS11 modules require authentication early on to be able to
preload objects, which we want to do to avoid costly roundtrips when the
HSM is actually reached over a network (Cloud HSM).

Unfortunately at open time we can't interact with the user becaue the
callbacks are only passed at object load time. later on.

This patch corrects this issue by providing a more feature rich open
call for providers.

Signed-off-by: Simo Sorce <simo@redhat.com>

Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from openssl#20131)

crypto/store/store_lib.c

@@ -66,6 +66,7 @@ OSSL_STORE_open_ex(const char *uri, OSSL_LIB_CTX *libctx, const char *propq,
                    OSSL_STORE_post_process_info_fn post_process,
                    void *post_process_data)
 {
+    struct ossl_passphrase_data_st pwdata = { 0 };
     const OSSL_STORE_LOADER *loader = NULL;
     OSSL_STORE_LOADER *fetched_loader = NULL;
     OSSL_STORE_LOADER_CTX *loader_ctx = NULL;
@@ -102,6 +103,13 @@ OSSL_STORE_open_ex(const char *uri, OSSL_LIB_CTX *libctx, const char *propq,
 
     ERR_set_mark();
 
+    if (ui_method != NULL
+        && (!ossl_pw_set_ui_method(&pwdata, ui_method, ui_data)
+            || !ossl_pw_enable_passphrase_caching(&pwdata))) {
+        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_CRYPTO_LIB);
+        goto err;
+    }
+
     /*
      * Try each scheme until we find one that could open the URI.
      *
@@ -135,17 +143,28 @@ OSSL_STORE_open_ex(const char *uri, OSSL_LIB_CTX *libctx, const char *propq,
             void *provctx = OSSL_PROVIDER_get0_provider_ctx(provider);
 
             no_loader_found = 0;
-            loader_ctx = fetched_loader->p_open(provctx, uri);
+            if (fetched_loader->p_open_ex != NULL) {
+                loader_ctx =
+                    fetched_loader->p_open_ex(provctx, uri, params,
+                                              ossl_pw_passphrase_callback_dec,
+                                              &pwdata);
+            } else {
+                loader_ctx = fetched_loader->p_open(provctx, uri);
+                if (loader_ctx != NULL &&
+                    !loader_set_params(fetched_loader, loader_ctx,
+                                       params, propq)) {
+                    (void)fetched_loader->p_close(loader_ctx);
+                    loader_ctx = NULL;
+                }
+            }
             if (loader_ctx == NULL) {
                 OSSL_STORE_LOADER_free(fetched_loader);
                 fetched_loader = NULL;
-            } else if (!loader_set_params(fetched_loader, loader_ctx,
-                                          params, propq)) {
-                (void)fetched_loader->p_close(loader_ctx);
-                OSSL_STORE_LOADER_free(fetched_loader);
-                fetched_loader = NULL;
             }
             loader = fetched_loader;
+
+            /* Clear any internally cached passphrase */
+            (void)ossl_pw_clear_passphrase_cache(&pwdata);
         }
     }
 
@@ -171,18 +190,13 @@ OSSL_STORE_open_ex(const char *uri, OSSL_LIB_CTX *libctx, const char *propq,
         || (ctx = OPENSSL_zalloc(sizeof(*ctx))) == NULL)
         goto err;
 
-    if (ui_method != NULL
-        && (!ossl_pw_set_ui_method(&ctx->pwdata, ui_method, ui_data)
-            || !ossl_pw_enable_passphrase_caching(&ctx->pwdata))) {
-        ERR_raise(ERR_LIB_OSSL_STORE, ERR_R_CRYPTO_LIB);
-        goto err;
-    }
     ctx->properties = propq_copy;
     ctx->fetched_loader = fetched_loader;
     ctx->loader = loader;
     ctx->loader_ctx = loader_ctx;
     ctx->post_process = post_process;
     ctx->post_process_data = post_process_data;
+    ctx->pwdata = pwdata;
 
     /*
      * If the attempt to open with the 'file' scheme loader failed and the

crypto/store/store_local.h

@@ -113,6 +113,7 @@ struct ossl_store_loader_st {
     OSSL_FUNC_store_close_fn *p_close;
     OSSL_FUNC_store_export_object_fn *p_export_object;
     OSSL_FUNC_store_delete_fn *p_delete;
+    OSSL_FUNC_store_open_ex_fn *p_open_ex;
 };
 DEFINE_LHASH_OF_EX(OSSL_STORE_LOADER);
 

crypto/store/store_meth.c

@@ -223,6 +223,10 @@ static void *loader_from_algorithm(int scheme_id, const OSSL_ALGORITHM *algodef,
             if (loader->p_delete == NULL)
                 loader->p_delete = OSSL_FUNC_store_delete(fns);
             break;
+        case OSSL_FUNC_STORE_OPEN_EX:
+            if (loader->p_open_ex == NULL)
+                loader->p_open_ex = OSSL_FUNC_store_open_ex(fns);
+            break;
         }
     }
 

include/openssl/core_dispatch.h

@@ -937,6 +937,7 @@ OSSL_CORE_MAKE_FUNC(int, decoder_export_object,
 #define OSSL_FUNC_STORE_CLOSE                       7
 #define OSSL_FUNC_STORE_EXPORT_OBJECT               8
 #define OSSL_FUNC_STORE_DELETE                      9
+#define OSSL_FUNC_STORE_OPEN_EX                     10
 OSSL_CORE_MAKE_FUNC(void *, store_open, (void *provctx, const char *uri))
 OSSL_CORE_MAKE_FUNC(void *, store_attach, (void *provctx, OSSL_CORE_BIO *in))
 OSSL_CORE_MAKE_FUNC(const OSSL_PARAM *, store_settable_ctx_params,
@@ -955,6 +956,9 @@ OSSL_CORE_MAKE_FUNC(int, store_export_object,
 OSSL_CORE_MAKE_FUNC(int, store_delete,
                     (void *provctx, const char *uri, const OSSL_PARAM params[],
                      OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg))
+OSSL_CORE_MAKE_FUNC(void *, store_open_ex,
+                    (void *provctx, const char *uri, const OSSL_PARAM params[],
+                     OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg))
 
 # ifdef __cplusplus
 }