proxy: Support C_WaitForSlotEvent() if CKF_DONT_BLOCK is specified

While fully implementing C_WaitForSlotEvent() would require a separate
thread to monitor events, it is straightforward to implement the
function if the CKF_DONT_BLOCK flag is given.

Suggested by David Ward.

4 files changed, 166 insertions, 15 deletions

diff --git a/p11-kit/Makefile.am b/p11-kit/Makefile.am
index 0155f7c..09a068e 100644
--- a/p11-kit/Makefile.am
+++ b/p11-kit/Makefile.am
@@ -409,7 +409,8 @@ check_LTLIBRARIES += \
 	mock-four.la \
 	mock-five.la \
 	mock-seven.la \
-	mock-eight.la
+	mock-eight.la \
+	mock-nine.la
 
 mock_one_la_SOURCES = p11-kit/mock-module-ep.c
 mock_one_la_LIBADD = libp11-test.la libp11-common.la
@@ -448,6 +449,10 @@ mock_eight_la_SOURCES = p11-kit/mock-module-ep6.c
 mock_eight_la_LDFLAGS = $(mock_one_la_LDFLAGS)
 mock_eight_la_LIBADD = $(mock_one_la_LIBADD)
 
+mock_nine_la_SOURCES = p11-kit/mock-module-ep7.c
+mock_nine_la_LDFLAGS = $(mock_one_la_LDFLAGS)
+mock_nine_la_LIBADD = $(mock_one_la_LIBADD)
+
 EXTRA_DIST += \
 	p11-kit/fixtures \
 	p11-kit/test-mock.c \
diff --git a/p11-kit/mock-module-ep7.c b/p11-kit/mock-module-ep7.c
new file mode 100644
index 0000000..51fad06
--- /dev/null
+++ b/p11-kit/mock-module-ep7.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2012 Stefan Walter
+ * Copyright (c) 2019 Red Hat, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *     * Redistributions of source code must retain the above
+ *       copyright notice, this list of conditions and the
+ *       following disclaimer.
+ *     * Redistributions in binary form must reproduce the
+ *       above copyright notice, this list of conditions and
+ *       the following disclaimer in the documentation and/or
+ *       other materials provided with the distribution.
+ *     * The names of contributors to this software may not be
+ *       used to endorse or promote products derived from this
+ *       software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Author: Stef Walter <stef@thewalter.net>, Daiki Ueno
+ */
+
+#include "config.h"
+
+#define CRYPTOKI_EXPORTS 1
+#include "pkcs11.h"
+
+#include "mock.h"
+#include "test.h"
+
+static CK_RV
+override_wait_for_slot_event (CK_FLAGS flags,
+			      CK_SLOT_ID_PTR slot,
+			      CK_VOID_PTR reserved)
+{
+	if (flags & CKF_DONT_BLOCK) {
+		*slot = MOCK_SLOT_ONE_ID;
+		return CKR_OK;
+	}
+
+	return mock_C_WaitForSlotEvent(flags, slot, reserved);
+}
+
+#ifdef OS_WIN32
+__declspec(dllexport)
+#endif
+CK_RV
+C_GetFunctionList (CK_FUNCTION_LIST_PTR_PTR list)
+{
+	mock_module_init ();
+	mock_module.C_GetFunctionList = C_GetFunctionList;
+	if (list == NULL)
+		return CKR_ARGUMENTS_BAD;
+	mock_module.C_WaitForSlotEvent = override_wait_for_slot_event;
+	*list = &mock_module;
+	return CKR_OK;
+}
diff --git a/p11-kit/proxy.c b/p11-kit/proxy.c
index ae88318..a9c7055 100644
--- a/p11-kit/proxy.c
+++ b/p11-kit/proxy.c
@@ -604,7 +604,40 @@ proxy_C_WaitForSlotEvent (CK_X_FUNCTION_LIST *self,
                           CK_SLOT_ID_PTR slot,
                           CK_VOID_PTR reserved)
 {
-	return CKR_FUNCTION_NOT_SUPPORTED;
+	State *state = (State *)self;
+	Proxy *py = state->px;
+	CK_FUNCTION_LIST_PTR *f;
+	CK_FUNCTION_LIST_PTR funcs;
+	CK_SLOT_ID real_slot;
+	unsigned int i;
+	CK_RV rv = CKR_NO_EVENT;
+
+	/* Only the non-blocking case is supported. */
+	if ((flags & CKF_DONT_BLOCK) == 0)
+		return CKR_FUNCTION_NOT_SUPPORTED;
+
+	p11_lock ();
+
+	for (f = py->inited; *f; ++f) {
+		funcs = *f;
+		assert (funcs != NULL);
+
+		rv = (funcs->C_WaitForSlotEvent) (flags, &real_slot, reserved);
+		if (rv == CKR_NO_EVENT)
+			continue;
+		if (rv != CKR_OK)
+			break;
+		for (i = 0; i < py->n_mappings; i++)
+			if (py->mappings[i].funcs == funcs &&
+			    py->mappings[i].real_slot == real_slot) {
+				*slot = py->mappings[i].wrap_slot;
+				break;
+			}
+	}
+
+	p11_unlock ();
+
+	return rv;
 }
 
 static CK_RV
@@ -1617,14 +1650,6 @@ proxy_C_GenerateRandom (CK_X_FUNCTION_LIST *self,
 	return (map.funcs->C_GenerateRandom) (handle, random_data, random_len);
 }
 
-static CK_RV
-module_C_WaitForSlotEvent (CK_FLAGS flags,
-                           CK_SLOT_ID_PTR slot,
-                           CK_VOID_PTR reserved)
-{
-	return proxy_C_WaitForSlotEvent (&global.virt.funcs, flags, slot, reserved);
-}
-
 /* --------------------------------------------------------------------
  * MODULE ENTRY POINT
  */
@@ -1737,11 +1762,8 @@ C_GetFunctionList (CK_FUNCTION_LIST_PTR_PTR list)
 		}
 	}
 
-	if (rv == CKR_OK) {
-		/* We use this as a check below */
-		module->C_WaitForSlotEvent = module_C_WaitForSlotEvent;
+	if (rv == CKR_OK)
 		*list = module;
-	}
 
 	if (loaded)
 		p11_kit_modules_release (loaded);
@@ -1769,7 +1791,21 @@ p11_proxy_module_cleanup (void)
 bool
 p11_proxy_module_check (CK_FUNCTION_LIST_PTR module)
 {
-	return (module->C_WaitForSlotEvent == module_C_WaitForSlotEvent);
+	State *state;
+	bool ret = false;
+
+	if (!p11_virtual_is_wrapper (module))
+		return false;
+
+	p11_lock ();
+	for (state = all_instances; state != NULL; state = state->next)
+		if (state->wrapped == module) {
+			ret = true;
+			break;
+		}
+	p11_unlock ();
+
+	return ret;
 }
 
 CK_RV
diff --git a/p11-kit/test-proxy.c b/p11-kit/test-proxy.c
index f61f37e..9a8f71d 100644
--- a/p11-kit/test-proxy.c
+++ b/p11-kit/test-proxy.c
@@ -234,6 +234,7 @@ teardown (void *unused)
 #define ENABLED "enable-in: test-proxy, p11-kit-proxy\n"
 #define DISABLED "disable-in: p11-kit-proxy\n"
 #define EIGHT_MODULE "module: mock-eight" SHLEXT "\n"
+#define NINE_MODULE "module: mock-nine" SHLEXT "\n"
 
 static CK_ULONG
 load_modules_and_count_slots (void)
@@ -343,6 +344,44 @@ test_slot_appear (void)
 	p11_proxy_module_cleanup ();
 }
 
+static void
+test_slot_event (void)
+{
+	CK_FUNCTION_LIST_PTR proxy;
+	CK_SLOT_ID slot;
+	CK_SLOT_ID slots[32];
+	CK_ULONG count;
+	CK_RV rv;
+
+	p11_test_file_write (test.directory, "nine.module", NINE_MODULE, strlen (NINE_MODULE));
+
+	rv = C_GetFunctionList (&proxy);
+	assert (rv == CKR_OK);
+
+	assert (p11_proxy_module_check (proxy));
+
+	rv = proxy->C_Initialize (NULL);
+	assert (rv == CKR_OK);
+
+	rv = proxy->C_GetSlotList (CK_FALSE, slots, &count);
+	assert (rv == CKR_OK);
+	assert (count == 2);
+
+	slot = 0;
+	rv = proxy->C_WaitForSlotEvent (0, &slot, NULL);
+	assert_num_eq (rv, CKR_FUNCTION_NOT_SUPPORTED);
+	assert_num_eq (slot, 0);
+
+	rv = proxy->C_WaitForSlotEvent (CKF_DONT_BLOCK, &slot, NULL);
+	assert_num_eq (rv, CKR_OK);
+	assert_num_eq (slot, slots[0]);
+
+	rv = proxy->C_Finalize (NULL);
+	assert_num_eq (rv, CKR_OK);
+
+	p11_proxy_module_cleanup ();
+}
+
 static CK_FUNCTION_LIST_PTR
 setup_mock_module (CK_SESSION_HANDLE *session)
 {
@@ -430,6 +469,7 @@ main (int argc,
 	p11_test (test_disable, "/proxy/disable");
 	p11_test (test_no_slot, "/proxy/no-slot");
 	p11_test (test_slot_appear, "/proxy/slot-appear");
+	p11_test (test_slot_event, "/proxy/slot-event");
 
 	test_mock_add_tests ("/proxy");