+/*
+ * Hook context data, attached as EXDATA to the RAND_DRBG
+ */
+typedef struct hook_ctx_st {
+ RAND_DRBG *drbg;
+ /*
+ * Currently, all DRBGs use the same get_entropy() callback.
+ * The tests however, don't assume this and store
+ * the original callback for every DRBG separately.
+ */
+ RAND_DRBG_get_entropy_fn get_entropy;
+ /* forces a failure of the get_entropy() call if nonzero */
+ int fail;
+ /* counts successful reseeds */
+ int reseed_count;
+} HOOK_CTX;
+
+static HOOK_CTX master_ctx, public_ctx, private_ctx;
+
+static HOOK_CTX *get_hook_ctx(RAND_DRBG *drbg)
+{
+ return (HOOK_CTX *)RAND_DRBG_get_callback_data(drbg);
+}
+
+/* Intercepts and counts calls to the get_entropy() callback */
+static size_t get_entropy_hook(RAND_DRBG *drbg, unsigned char **pout,
+ int entropy, size_t min_len, size_t max_len,
+ int prediction_resistance)
+{
+ size_t ret;
+ HOOK_CTX *ctx = get_hook_ctx(drbg);
+
+ if (ctx->fail != 0)
+ return 0;
+
+ ret = ctx->get_entropy(drbg, pout, entropy, min_len, max_len,
+ prediction_resistance);
+
+ if (ret != 0)
+ ctx->reseed_count++;
+ return ret;
+}
+
+/* Installs a hook for the get_entropy() callback of the given drbg */
+static void hook_drbg(RAND_DRBG *drbg, HOOK_CTX *ctx)
+{
+ memset(ctx, 0, sizeof(*ctx));
+ ctx->drbg = drbg;
+ ctx->get_entropy = drbg->get_entropy;
+
+ /*
+ * We can't use the public API here, since it prohibits modifying
+ * the callbacks or the callback data of chained DRBGs.
+ */
+ drbg->get_entropy = get_entropy_hook;
+ drbg->callback_data = ctx;
+}
+
+/* Installs the hook for the get_entropy() callback of the given drbg */
+static void unhook_drbg(RAND_DRBG *drbg)
+{
+ HOOK_CTX *ctx = drbg->callback_data;
+
+ if (ctx != NULL)
+ drbg->get_entropy = ctx->get_entropy;
+}
+
+/* Resets the given hook context */
+static void reset_hook_ctx(HOOK_CTX *ctx)
+{
+ ctx->fail = 0;
+ ctx->reseed_count = 0;
+}
+
+/* Resets all drbg hook contexts */
+static void reset_drbg_hook_ctx(void)
+{
+ reset_hook_ctx(&master_ctx);
+ reset_hook_ctx(&public_ctx);
+ reset_hook_ctx(&private_ctx);
+}
+
+/*
+ * Generates random output using RAND_bytes() and RAND_priv_bytes()
+ * and checks whether the three shared DRBGs were reseeded as
+ * expected.
+ *
+ * |expect_success|: expected outcome (as reported by RAND_status())
+ * |master|, |public|, |private|: pointers to the three shared DRBGs
+ * |expect_xxx_reseed| =
+ * 1: it is expected that the specified DRBG is reseeded
+ * 0: it is expected that the specified DRBG is not reseeded
+ * -1: don't check whether the specified DRBG was reseeded or not
+ * |reseed_time|: if nonzero, used instead of time(NULL) to set the
+ * |before_reseed| time.
+ */
+static int test_drbg_reseed(int expect_success,
+ RAND_DRBG *master,
+ RAND_DRBG *public,
+ RAND_DRBG *private,
+ int expect_master_reseed,
+ int expect_public_reseed,
+ int expect_private_reseed,
+ time_t reseed_time
+ )
+{
+ unsigned char buf[32];
+ time_t before_reseed, after_reseed;
+ int expected_state = (expect_success ? DRBG_READY : DRBG_ERROR);
+
+ /*
+ * step 1: check preconditions
+ */
+
+ /* Test whether seed propagation is enabled */
+ if (!TEST_int_ne(master->reseed_prop_counter, 0)
+ || !TEST_int_ne(public->reseed_prop_counter, 0)
+ || !TEST_int_ne(private->reseed_prop_counter, 0))
+ return 0;
+
+ /* Check whether the master DRBG's reseed counter is the largest one */
+ if (!TEST_int_le(public->reseed_prop_counter, master->reseed_prop_counter)
+ || !TEST_int_le(private->reseed_prop_counter, master->reseed_prop_counter))
+ return 0;
+
+ /*
+ * step 2: generate random output
+ */
+
+ if (reseed_time == 0)
+ reseed_time = time(NULL);
+
+ /* Generate random output from the public and private DRBG */
+ before_reseed = expect_master_reseed == 1 ? reseed_time : 0;
+ if (!TEST_int_eq(RAND_bytes(buf, sizeof(buf)), expect_success)
+ || !TEST_int_eq(RAND_priv_bytes(buf, sizeof(buf)), expect_success))
+ return 0;
+ after_reseed = time(NULL);
+
+
+ /*
+ * step 3: check postconditions
+ */
+
+ /* Test whether reseeding succeeded as expected */
+ if (!TEST_int_eq(master->state, expected_state)
+ || !TEST_int_eq(public->state, expected_state)
+ || !TEST_int_eq(private->state, expected_state))
+ return 0;
+
+ if (expect_master_reseed >= 0) {
+ /* Test whether master DRBG was reseeded as expected */
+ if (!TEST_int_eq(master_ctx.reseed_count, expect_master_reseed))
+ return 0;
+ }
+
+ if (expect_public_reseed >= 0) {
+ /* Test whether public DRBG was reseeded as expected */
+ if (!TEST_int_eq(public_ctx.reseed_count, expect_public_reseed))
+ return 0;
+ }
+
+ if (expect_private_reseed >= 0) {
+ /* Test whether public DRBG was reseeded as expected */
+ if (!TEST_int_eq(private_ctx.reseed_count, expect_private_reseed))
+ return 0;
+ }
+
+ if (expect_success == 1) {
+ /* Test whether all three reseed counters are synchronized */
+ if (!TEST_int_eq(public->reseed_prop_counter, master->reseed_prop_counter)
+ || !TEST_int_eq(private->reseed_prop_counter, master->reseed_prop_counter))
+ return 0;
+
+ /* Test whether reseed time of master DRBG is set correctly */
+ if (!TEST_time_t_le(before_reseed, master->reseed_time)
+ || !TEST_time_t_le(master->reseed_time, after_reseed))
+ return 0;
+
+ /* Test whether reseed times of child DRBGs are synchronized with master */
+ if (!TEST_time_t_ge(public->reseed_time, master->reseed_time)
+ || !TEST_time_t_ge(private->reseed_time, master->reseed_time))
+ return 0;
+ } else {
+ ERR_clear_error();
+ }
+
+ return 1;
+}
+
+
+#if defined(OPENSSL_SYS_UNIX)
+/*
+ * Test whether master, public and private DRBG are reseeded after
+ * forking the process.
+ */
+static int test_drbg_reseed_after_fork(RAND_DRBG *master,
+ RAND_DRBG *public,
+ RAND_DRBG *private)
+{
+ pid_t pid;
+ int status=0;
+
+ pid = fork();
+ if (!TEST_int_ge(pid, 0))
+ return 0;
+
+ if (pid > 0) {
+ /* I'm the parent; wait for the child and check its exit code */
+ return TEST_int_eq(waitpid(pid, &status, 0), pid) && TEST_int_eq(status, 0);
+ }
+
+ /* I'm the child; check whether all three DRBGs reseed. */
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 1, 1, 1, 0)))
+ status = 1;
+
+ /* Remove hooks */
+ unhook_drbg(master);
+ unhook_drbg(public);
+ unhook_drbg(private);
+ exit(status);
+}
+#endif
+
+/*
+ * Test whether the default rand_method (RAND_OpenSSL()) is
+ * setup correctly, in particular whether reseeding works
+ * as designed.
+ */
+static int test_rand_drbg_reseed(void)
+{
+ RAND_DRBG *master, *public, *private;
+ unsigned char rand_add_buf[256];
+ int rv=0;
+ time_t before_reseed;
+
+ /* Check whether RAND_OpenSSL() is the default method */
+ if (!TEST_ptr_eq(RAND_get_rand_method(), RAND_OpenSSL()))
+ return 0;
+
+ /* All three DRBGs should be non-null */
+ if (!TEST_ptr(master = RAND_DRBG_get0_master())
+ || !TEST_ptr(public = RAND_DRBG_get0_public())
+ || !TEST_ptr(private = RAND_DRBG_get0_private()))
+ return 0;
+
+ /* There should be three distinct DRBGs, two of them chained to master */
+ if (!TEST_ptr_ne(public, private)
+ || !TEST_ptr_ne(public, master)
+ || !TEST_ptr_ne(private, master)
+ || !TEST_ptr_eq(public->parent, master)
+ || !TEST_ptr_eq(private->parent, master))
+ return 0;
+
+ /* Disable CRNG testing for the master DRBG */
+ if (!TEST_true(disable_crngt(master)))
+ return 0;
+
+ /* uninstantiate the three global DRBGs */
+ RAND_DRBG_uninstantiate(private);
+ RAND_DRBG_uninstantiate(public);
+ RAND_DRBG_uninstantiate(master);
+
+
+ /* Install hooks for the following tests */
+ hook_drbg(master, &master_ctx);
+ hook_drbg(public, &public_ctx);
+ hook_drbg(private, &private_ctx);
+
+
+ /*
+ * Test initial seeding of shared DRBGs
+ */
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 1, 1, 1, 0)))
+ goto error;
+ reset_drbg_hook_ctx();
+
+
+ /*
+ * Test initial state of shared DRBGs
+ */
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 0, 0, 0)))
+ goto error;
+ reset_drbg_hook_ctx();
+
+ /*
+ * Test whether the public and private DRBG are both reseeded when their
+ * reseed counters differ from the master's reseed counter.
+ */
+ master->reseed_prop_counter++;
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 1, 1, 0)))
+ goto error;
+ reset_drbg_hook_ctx();
+
+ /*
+ * Test whether the public DRBG is reseeded when its reseed counter differs
+ * from the master's reseed counter.
+ */
+ master->reseed_prop_counter++;
+ private->reseed_prop_counter++;
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 1, 0, 0)))
+ goto error;
+ reset_drbg_hook_ctx();
+
+ /*
+ * Test whether the private DRBG is reseeded when its reseed counter differs
+ * from the master's reseed counter.
+ */
+ master->reseed_prop_counter++;
+ public->reseed_prop_counter++;
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 0, 1, 0)))
+ goto error;
+ reset_drbg_hook_ctx();
+
+#if defined(OPENSSL_SYS_UNIX)
+ if (!TEST_true(test_drbg_reseed_after_fork(master, public, private)))
+ goto error;
+#endif
+
+ /* fill 'randomness' buffer with some arbitrary data */
+ memset(rand_add_buf, 'r', sizeof(rand_add_buf));
+
+#ifndef FIPS_MODULE
+ /*
+ * Test whether all three DRBGs are reseeded by RAND_add().
+ * The before_reseed time has to be measured here and passed into the
+ * test_drbg_reseed() test, because the master DRBG gets already reseeded
+ * in RAND_add(), whence the check for the condition
+ * before_reseed <= master->reseed_time will fail if the time value happens
+ * to increase between the RAND_add() and the test_drbg_reseed() call.
+ */
+ before_reseed = time(NULL);
+ RAND_add(rand_add_buf, sizeof(rand_add_buf), sizeof(rand_add_buf));
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 1, 1, 1,
+ before_reseed)))
+ goto error;
+ reset_drbg_hook_ctx();
+
+
+ /*
+ * Test whether none of the DRBGs is reseed if the master fails to reseed
+ */
+ master_ctx.fail = 1;
+ master->reseed_prop_counter++;
+ RAND_add(rand_add_buf, sizeof(rand_add_buf), sizeof(rand_add_buf));
+ if (!TEST_true(test_drbg_reseed(0, master, public, private, 0, 0, 0, 0)))
+ goto error;
+ reset_drbg_hook_ctx();
+#else /* FIPS_MODULE */
+ /*
+ * In FIPS mode, random data provided by the application via RAND_add()
+ * is not considered a trusted entropy source. It is only treated as
+ * additional_data and no reseeding is forced. This test assures that
+ * no reseeding occurs.
+ */
+ before_reseed = time(NULL);
+ RAND_add(rand_add_buf, sizeof(rand_add_buf), sizeof(rand_add_buf));
+ if (!TEST_true(test_drbg_reseed(1, master, public, private, 0, 0, 0,
+ before_reseed)))
+ goto error;
+ reset_drbg_hook_ctx();
+#endif