crypto: testmgr - add helpers for fuzzing against generic implementation
Add some helper functions in preparation for fuzz testing algorithms
against their generic implementation.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 834eea5..feb3ff2 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -128,6 +128,7 @@ struct kpp_test_suite {
struct alg_test_desc {
const char *alg;
+ const char *generic_driver;
int (*test)(const struct alg_test_desc *desc, const char *driver,
u32 type, u32 mask);
int fips_allowed; /* set if alg is allowed in fips mode */
@@ -745,6 +746,91 @@ static int build_cipher_test_sglists(struct cipher_test_sglists *tsgls,
}
#ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
+
+/* Generate a random length in range [0, max_len], but prefer smaller values */
+static unsigned int generate_random_length(unsigned int max_len)
+{
+ unsigned int len = prandom_u32() % (max_len + 1);
+
+ switch (prandom_u32() % 4) {
+ case 0:
+ return len % 64;
+ case 1:
+ return len % 256;
+ case 2:
+ return len % 1024;
+ default:
+ return len;
+ }
+}
+
+/* Sometimes make some random changes to the given data buffer */
+static void mutate_buffer(u8 *buf, size_t count)
+{
+ size_t num_flips;
+ size_t i;
+ size_t pos;
+
+ /* Sometimes flip some bits */
+ if (prandom_u32() % 4 == 0) {
+ num_flips = min_t(size_t, 1 << (prandom_u32() % 8), count * 8);
+ for (i = 0; i < num_flips; i++) {
+ pos = prandom_u32() % (count * 8);
+ buf[pos / 8] ^= 1 << (pos % 8);
+ }
+ }
+
+ /* Sometimes flip some bytes */
+ if (prandom_u32() % 4 == 0) {
+ num_flips = min_t(size_t, 1 << (prandom_u32() % 8), count);
+ for (i = 0; i < num_flips; i++)
+ buf[prandom_u32() % count] ^= 0xff;
+ }
+}
+
+/* Randomly generate 'count' bytes, but sometimes make them "interesting" */
+static void generate_random_bytes(u8 *buf, size_t count)
+{
+ u8 b;
+ u8 increment;
+ size_t i;
+
+ if (count == 0)
+ return;
+
+ switch (prandom_u32() % 8) { /* Choose a generation strategy */
+ case 0:
+ case 1:
+ /* All the same byte, plus optional mutations */
+ switch (prandom_u32() % 4) {
+ case 0:
+ b = 0x00;
+ break;
+ case 1:
+ b = 0xff;
+ break;
+ default:
+ b = (u8)prandom_u32();
+ break;
+ }
+ memset(buf, b, count);
+ mutate_buffer(buf, count);
+ break;
+ case 2:
+ /* Ascending or descending bytes, plus optional mutations */
+ increment = (u8)prandom_u32();
+ b = (u8)prandom_u32();
+ for (i = 0; i < count; i++, b += increment)
+ buf[i] = b;
+ mutate_buffer(buf, count);
+ break;
+ default:
+ /* Fully random bytes */
+ for (i = 0; i < count; i++)
+ buf[i] = (u8)prandom_u32();
+ }
+}
+
static char *generate_random_sgl_divisions(struct test_sg_division *divs,
size_t max_divs, char *p, char *end,
bool gen_flushes, u32 req_flags)
@@ -899,6 +985,48 @@ static void crypto_reenable_simd_for_test(void)
__this_cpu_write(crypto_simd_disabled_for_test, false);
preempt_enable();
}
+
+/*
+ * Given an algorithm name, build the name of the generic implementation of that
+ * algorithm, assuming the usual naming convention. Specifically, this appends
+ * "-generic" to every part of the name that is not a template name. Examples:
+ *
+ * aes => aes-generic
+ * cbc(aes) => cbc(aes-generic)
+ * cts(cbc(aes)) => cts(cbc(aes-generic))
+ * rfc7539(chacha20,poly1305) => rfc7539(chacha20-generic,poly1305-generic)
+ *
+ * Return: 0 on success, or -ENAMETOOLONG if the generic name would be too long
+ */
+static int build_generic_driver_name(const char *algname,
+ char driver_name[CRYPTO_MAX_ALG_NAME])
+{
+ const char *in = algname;
+ char *out = driver_name;
+ size_t len = strlen(algname);
+
+ if (len >= CRYPTO_MAX_ALG_NAME)
+ goto too_long;
+ do {
+ const char *in_saved = in;
+
+ while (*in && *in != '(' && *in != ')' && *in != ',')
+ *out++ = *in++;
+ if (*in != '(' && in > in_saved) {
+ len += 8;
+ if (len >= CRYPTO_MAX_ALG_NAME)
+ goto too_long;
+ memcpy(out, "-generic", 8);
+ out += 8;
+ }
+ } while ((*out++ = *in++) != '\0');
+ return 0;
+
+too_long:
+ pr_err("alg: generic driver name for \"%s\" would be too long\n",
+ algname);
+ return -ENAMETOOLONG;
+}
#else /* !CONFIG_CRYPTO_MANAGER_EXTRA_TESTS */
static void crypto_disable_simd_for_test(void)
{