efi_selftest: unit test for EFI_RNG_PROTOCOL

Provide a unit test for the EFI_RNG_PROTOCOL.

The list of algorithms is read. Two random numbers are generated. The test
checks that the two numbers differ.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

diff --git a/lib/efi_selftest/Makefile b/lib/efi_selftest/Makefile
index 487cb4c674006400faa00202c61e86a969d65ace..3ad96e1cbf084209cee54d33e8fa47bb2bdaa44e 100644 (file)
--- a/lib/efi_selftest/Makefile
+++ b/lib/efi_selftest/Makefile
@@ -47,6 +47,7 @@ efi_selftest_unicode_collation.o
 
 obj-$(CONFIG_CPU_V7) += efi_selftest_unaligned.o
 obj-$(CONFIG_EFI_LOADER_HII) += efi_selftest_hii.o
+obj-$(CONFIG_EFI_RNG_PROTOCOL) += efi_selftest_rng.o
 obj-$(CONFIG_EFI_GET_TIME) += efi_selftest_rtc.o
 
 ifeq ($(CONFIG_GENERATE_ACPI_TABLE),)

diff --git a/lib/efi_selftest/efi_selftest_rng.c b/lib/efi_selftest/efi_selftest_rng.c
new file mode 100644 (file)
index 0000000..fca9749
--- /dev/null
+++ b/lib/efi_selftest/efi_selftest_rng.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * efi_selftest_rng
+ *
+ * Copyright (c) 2019 Heinrich Schuchardt <xypron.glpk@gmx.de>
+ *
+ * Test the random number generator service.
+ */
+
+#include <efi_selftest.h>
+#include <efi_rng.h>
+
+#define RNG_LEN 9
+
+static struct efi_boot_services *boottime;
+static efi_guid_t efi_rng_guid = EFI_RNG_PROTOCOL_GUID;
+
+/*
+ * Setup unit test.
+ *
+ * @handle:    handle of the loaded image
+ * @systable:  system table
+ * @return:    EFI_ST_SUCCESS for success
+ */
+static int setup(const efi_handle_t handle,
+                const struct efi_system_table *systable)
+{
+       boottime = systable->boottime;
+       return EFI_ST_SUCCESS;
+}
+
+/*
+ * Execute unit test.
+ *
+ * Retrieve available RNG algorithms.
+ * Retrieve two random values and compare them.
+ *
+ * @return:    EFI_ST_SUCCESS for success
+ */
+static int execute(void)
+{
+       efi_status_t ret;
+       efi_uintn_t size;
+       struct efi_rng_protocol *rng;
+       efi_guid_t *algo_list;
+       u8 rnd1[RNG_LEN] __aligned(4), rnd2[RNG_LEN] __aligned(4);
+       int r;
+
+       /* Get random number generator protocol */
+       ret = boottime->locate_protocol(&efi_rng_guid, NULL, (void **)&rng);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error(
+                       "Random number generator protocol not available\n");
+               return EFI_ST_FAILURE;
+       }
+
+       ret = rng->get_info(rng, &size, NULL);
+       if (ret != EFI_BUFFER_TOO_SMALL) {
+               efi_st_error("Could not retrieve alorithm list size\n");
+               return EFI_ST_FAILURE;
+       }
+       if (size < sizeof(efi_guid_t)) {
+               efi_st_error("Empty alorithm list\n");
+               return EFI_ST_FAILURE;
+       }
+
+       ret = boottime->allocate_pool(EFI_LOADER_DATA, size,
+                                     (void **)&algo_list);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("Could not allocate pool memory\n");
+               return EFI_ST_FAILURE;
+       }
+
+       ret = rng->get_info(rng, &size, algo_list);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("Could not get info\n");
+               return EFI_ST_FAILURE;
+       }
+       if (size < sizeof(efi_guid_t)) {
+               efi_st_error("Empty alorithm list\n");
+               return EFI_ST_FAILURE;
+       }
+
+       memset(rnd1, 0, RNG_LEN);
+       memset(rnd2, 0, RNG_LEN);
+
+       ret = rng->get_rng(rng, NULL, RNG_LEN - 1, &rnd1[1]);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("Could not get random value\n");
+               return EFI_ST_FAILURE;
+       }
+       ret = rng->get_rng(rng, algo_list, RNG_LEN - 1, &rnd2[1]);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("Could not get random value\n");
+               return EFI_ST_FAILURE;
+       }
+       r = memcmp(rnd1, rnd2, RNG_LEN);
+       if (!r) {
+               efi_st_error("Two equal consecutive random numbers\n");
+               return EFI_ST_FAILURE;
+       }
+
+       ret = boottime->free_pool(algo_list);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("Could not free pool memory\n");
+               return EFI_ST_FAILURE;
+       }
+
+       return EFI_ST_SUCCESS;
+}
+
+EFI_UNIT_TEST(rng) = {
+       .name = "random number generator",
+       .phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
+       .setup = setup,
+       .execute = execute,
+};