crypto: testmgr - test the !may_use_simd() fallback code

All crypto API algorithms are supposed to support the case where they
are called in a context where SIMD instructions are unusable, e.g. IRQ
context on some architectures.  However, this isn't tested for by the
self-tests, causing bugs to go undetected.

Now that all algorithms have been converted to use crypto_simd_usable(),
update the self-tests to test the no-SIMD case.  First, a bool
testvec_config::nosimd is added.  When set, the crypto operation is
executed with preemption disabled and with crypto_simd_usable() mocked
out to return false on the current CPU.

A bool test_sg_division::nosimd is also added.  For hash algorithms it's
honored by the corresponding ->update().  By setting just a subset of
these bools, the case where some ->update()s are done in SIMD context
and some are done in no-SIMD context is also tested.

These bools are then randomly set by generate_random_testvec_config().

For now, all no-SIMD testing is limited to the extra crypto self-tests,
because it might be a bit too invasive for the regular self-tests.
But this could be changed later.

This has already found bugs in the arm64 AES-GCM and ChaCha algorithms.
This would have found some past bugs as well.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 92 insertions, 24 deletions

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 52417dde811f..2c2ddebb48d3 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -234,12 +234,14 @@ enum finalization_type {
  *                                @offset
  * @flush_type: for hashes, whether an update() should be done now vs.
  *              continuing to accumulate data
+ * @nosimd: if doing the pending update(), do it with SIMD disabled?
  */
 struct test_sg_division {
         unsigned int proportion_of_total;
         unsigned int offset;
         bool offset_relative_to_alignmask;
         enum flush_type flush_type;
+        bool nosimd;
 };
 
 /**
@@ -259,6 +261,7 @@ struct test_sg_division {
  * @iv_offset_relative_to_alignmask: if true, add the algorithm's alignmask to
  *                                   the @iv_offset
  * @finalization_type: what finalization function to use for hashes
+ * @nosimd: execute with SIMD disabled?  Requires !CRYPTO_TFM_REQ_MAY_SLEEP.
  */
 struct testvec_config {
         const char *name;
@@ -269,6 +272,7 @@ struct testvec_config {
         unsigned int iv_offset;
         bool iv_offset_relative_to_alignmask;
         enum finalization_type finalization_type;
+        bool nosimd;
 };
 
 #define TESTVEC_CONFIG_NAMELEN  192
@@ -420,8 +424,11 @@ static unsigned int count_test_sg_divisions(const struct test_sg_division *divs)
         return ndivs;
 }
 
+#define SGDIVS_HAVE_FLUSHES     BIT(0)
+#define SGDIVS_HAVE_NOSIMD      BIT(1)
+
 static bool valid_sg_divisions(const struct test_sg_division *divs,
-                               unsigned int count, bool *any_flushes_ret)
+                               unsigned int count, int *flags_ret)
 {
         unsigned int total = 0;
         unsigned int i;
@@ -432,7 +439,9 @@ static bool valid_sg_divisions(const struct test_sg_division *divs,
                         return false;
                 total += divs[i].proportion_of_total;
                 if (divs[i].flush_type != FLUSH_TYPE_NONE)
-                        *any_flushes_ret = true;
+                        *flags_ret |= SGDIVS_HAVE_FLUSHES;
+                if (divs[i].nosimd)
+                        *flags_ret |= SGDIVS_HAVE_NOSIMD;
         }
         return total == TEST_SG_TOTAL &&
                 memchr_inv(&divs[i], 0, (count - i) * sizeof(divs[0])) == NULL;
@@ -445,19 +454,18 @@ static bool valid_sg_divisions(const struct test_sg_division *divs,
  */
 static bool valid_testvec_config(const struct testvec_config *cfg)
 {
-        bool any_flushes = false;
+        int flags = 0;
 
         if (cfg->name == NULL)
                 return false;
 
         if (!valid_sg_divisions(cfg->src_divs, ARRAY_SIZE(cfg->src_divs),
-                                &any_flushes))
+                                &flags))
                 return false;
 
         if (cfg->dst_divs[0].proportion_of_total) {
                 if (!valid_sg_divisions(cfg->dst_divs,
-                                        ARRAY_SIZE(cfg->dst_divs),
-                                        &any_flushes))
+                                        ARRAY_SIZE(cfg->dst_divs), &flags))
                         return false;
         } else {
                 if (memchr_inv(cfg->dst_divs, 0, sizeof(cfg->dst_divs)))
@@ -470,7 +478,12 @@ static bool valid_testvec_config(const struct testvec_config *cfg)
             MAX_ALGAPI_ALIGNMASK + 1)
                 return false;
 
-        if (any_flushes && cfg->finalization_type == FINALIZATION_TYPE_DIGEST)
+        if ((flags & (SGDIVS_HAVE_FLUSHES | SGDIVS_HAVE_NOSIMD)) &&
+            cfg->finalization_type == FINALIZATION_TYPE_DIGEST)
+                return false;
+
+        if ((cfg->nosimd || (flags & SGDIVS_HAVE_NOSIMD)) &&
+            (cfg->req_flags & CRYPTO_TFM_REQ_MAY_SLEEP))
                 return false;
 
         return true;
@@ -731,13 +744,14 @@ static int build_cipher_test_sglists(struct cipher_test_sglists *tsgls,
 #ifdef CONFIG_CRYPTO_MANAGER_EXTRA_TESTS
 static char *generate_random_sgl_divisions(struct test_sg_division *divs,
                                            size_t max_divs, char *p, char *end,
-                                           bool gen_flushes)
+                                           bool gen_flushes, u32 req_flags)
 {
         struct test_sg_division *div = divs;
         unsigned int remaining = TEST_SG_TOTAL;
 
         do {
                 unsigned int this_len;
+                const char *flushtype_str;
 
                 if (div == &divs[max_divs - 1] || prandom_u32() % 2 == 0)
                         this_len = remaining;
@@ -766,11 +780,31 @@ static char *generate_random_sgl_divisions(struct test_sg_division *divs,
                         }
                 }
 
+                if (div->flush_type != FLUSH_TYPE_NONE &&
+                    !(req_flags & CRYPTO_TFM_REQ_MAY_SLEEP) &&
+                    prandom_u32() % 2 == 0)
+                        div->nosimd = true;
+
+                switch (div->flush_type) {
+                case FLUSH_TYPE_FLUSH:
+                        if (div->nosimd)
+                                flushtype_str = "<flush,nosimd>";
+                        else
+                                flushtype_str = "<flush>";
+                        break;
+                case FLUSH_TYPE_REIMPORT:
+                        if (div->nosimd)
+                                flushtype_str = "<reimport,nosimd>";
+                        else
+                                flushtype_str = "<reimport>";
+                        break;
+                default:
+                        flushtype_str = "";
+                        break;
+                }
+
                 BUILD_BUG_ON(TEST_SG_TOTAL != 10000); /* for "%u.%u%%" */
-                p += scnprintf(p, end - p, "%s%u.%u%%@%s+%u%s",
-                               div->flush_type == FLUSH_TYPE_NONE ? "" :
-                               div->flush_type == FLUSH_TYPE_FLUSH ?
-                               "<flush> " : "<reimport> ",
+                p += scnprintf(p, end - p, "%s%u.%u%%@%s+%u%s", flushtype_str,
                                this_len / 100, this_len % 100,
                                div->offset_relative_to_alignmask ?
                                         "alignmask" : "",
@@ -820,18 +854,26 @@ static void generate_random_testvec_config(struct testvec_config *cfg,
                 break;
         }
 
+        if (!(cfg->req_flags & CRYPTO_TFM_REQ_MAY_SLEEP) &&
+            prandom_u32() % 2 == 0) {
+                cfg->nosimd = true;
+                p += scnprintf(p, end - p, " nosimd");
+        }
+
         p += scnprintf(p, end - p, " src_divs=[");
         p = generate_random_sgl_divisions(cfg->src_divs,
                                           ARRAY_SIZE(cfg->src_divs), p, end,
                                           (cfg->finalization_type !=
-                                           FINALIZATION_TYPE_DIGEST));
+                                           FINALIZATION_TYPE_DIGEST),
+                                          cfg->req_flags);
         p += scnprintf(p, end - p, "]");
 
         if (!cfg->inplace && prandom_u32() % 2 == 0) {
                 p += scnprintf(p, end - p, " dst_divs=[");
                 p = generate_random_sgl_divisions(cfg->dst_divs,
                                                   ARRAY_SIZE(cfg->dst_divs),
-                                                  p, end, false);
+                                                  p, end, false,
+                                                  cfg->req_flags);
                 p += scnprintf(p, end - p, "]");
         }
 
@@ -864,6 +906,23 @@ static void crypto_reenable_simd_for_test(void)
 }
 #endif /* !CONFIG_CRYPTO_MANAGER_EXTRA_TESTS */
 
+static int do_ahash_op(int (*op)(struct ahash_request *req),
+                       struct ahash_request *req,
+                       struct crypto_wait *wait, bool nosimd)
+{
+        int err;
+
+        if (nosimd)
+                crypto_disable_simd_for_test();
+
+        err = op(req);
+
+        if (nosimd)
+                crypto_reenable_simd_for_test();
+
+        return crypto_wait_req(err, wait);
+}
+
 static int check_nonfinal_hash_op(const char *op, int err,
                                   u8 *result, unsigned int digestsize,
                                   const char *driver, unsigned int vec_num,
@@ -938,7 +997,7 @@ static int test_hash_vec_cfg(const char *driver,
                 ahash_request_set_callback(req, req_flags, crypto_req_done,
                                            &wait);
                 ahash_request_set_crypt(req, tsgl->sgl, result, vec->psize);
-                err = crypto_wait_req(crypto_ahash_digest(req), &wait);
+                err = do_ahash_op(crypto_ahash_digest, req, &wait, cfg->nosimd);
                 if (err) {
                         pr_err("alg: hash: %s digest() failed with err %d on test vector %u, cfg=\"%s\"\n",
                                driver, err, vec_num, cfg->name);
@@ -951,7 +1010,7 @@ static int test_hash_vec_cfg(const char *driver,
 
         ahash_request_set_callback(req, req_flags, crypto_req_done, &wait);
         ahash_request_set_crypt(req, NULL, result, 0);
-        err = crypto_wait_req(crypto_ahash_init(req), &wait);
+        err = do_ahash_op(crypto_ahash_init, req, &wait, cfg->nosimd);
         err = check_nonfinal_hash_op("init", err, result, digestsize,
                                      driver, vec_num, cfg);
         if (err)
@@ -967,7 +1026,8 @@ static int test_hash_vec_cfg(const char *driver,
                                                    crypto_req_done, &wait);
                         ahash_request_set_crypt(req, pending_sgl, result,
                                                 pending_len);
-                        err = crypto_wait_req(crypto_ahash_update(req), &wait);
+                        err = do_ahash_op(crypto_ahash_update, req, &wait,
+                                          divs[i]->nosimd);
                         err = check_nonfinal_hash_op("update", err,
                                                      result, digestsize,
                                                      driver, vec_num, cfg);
@@ -1010,12 +1070,12 @@ static int test_hash_vec_cfg(const char *driver,
         ahash_request_set_crypt(req, pending_sgl, result, pending_len);
         if (cfg->finalization_type == FINALIZATION_TYPE_FINAL) {
                 /* finish with update() and final() */
-                err = crypto_wait_req(crypto_ahash_update(req), &wait);
+                err = do_ahash_op(crypto_ahash_update, req, &wait, cfg->nosimd);
                 err = check_nonfinal_hash_op("update", err, result, digestsize,
                                              driver, vec_num, cfg);
                 if (err)
                         return err;
-                err = crypto_wait_req(crypto_ahash_final(req), &wait);
+                err = do_ahash_op(crypto_ahash_final, req, &wait, cfg->nosimd);
                 if (err) {
                         pr_err("alg: hash: %s final() failed with err %d on test vector %u, cfg=\"%s\"\n",
                                driver, err, vec_num, cfg->name);
@@ -1023,7 +1083,7 @@ static int test_hash_vec_cfg(const char *driver,
                 }
         } else {
                 /* finish with finup() */
-                err = crypto_wait_req(crypto_ahash_finup(req), &wait);
+                err = do_ahash_op(crypto_ahash_finup, req, &wait, cfg->nosimd);
                 if (err) {
                         pr_err("alg: hash: %s finup() failed with err %d on test vector %u, cfg=\"%s\"\n",
                                driver, err, vec_num, cfg->name);
@@ -1259,8 +1319,12 @@ static int test_aead_vec_cfg(const char *driver, int enc,
         aead_request_set_crypt(req, tsgls->src.sgl_ptr, tsgls->dst.sgl_ptr,
                                enc ? vec->plen : vec->clen, iv);
         aead_request_set_ad(req, vec->alen);
-        err = crypto_wait_req(enc ? crypto_aead_encrypt(req) :
-                              crypto_aead_decrypt(req), &wait);
+        if (cfg->nosimd)
+                crypto_disable_simd_for_test();
+        err = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);
+        if (cfg->nosimd)
+                crypto_reenable_simd_for_test();
+        err = crypto_wait_req(err, &wait);
         if (err) {
                 if (err == -EBADMSG && vec->novrfy)
                         return 0;
@@ -1594,8 +1658,12 @@ static int test_skcipher_vec_cfg(const char *driver, int enc,
         skcipher_request_set_callback(req, req_flags, crypto_req_done, &wait);
         skcipher_request_set_crypt(req, tsgls->src.sgl_ptr, tsgls->dst.sgl_ptr,
                                    vec->len, iv);
-        err = crypto_wait_req(enc ? crypto_skcipher_encrypt(req) :
-                              crypto_skcipher_decrypt(req), &wait);
+        if (cfg->nosimd)
+                crypto_disable_simd_for_test();
+        err = enc ? crypto_skcipher_encrypt(req) : crypto_skcipher_decrypt(req);
+        if (cfg->nosimd)
+                crypto_reenable_simd_for_test();
+        err = crypto_wait_req(err, &wait);
         if (err) {
                 pr_err("alg: skcipher: %s %s failed with err %d on test vector %u, cfg=\"%s\"\n",
                        driver, op, err, vec_num, cfg->name);