[PATCH v2 2/3] tests: correctly validate result buffer in hash/hmac tests

["Daniel P. Berrangé" <berrange@redhat.com>]

Validate that the pre-allocated buffer pointer was not overwritten
by the hash/hmac APIs.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 tests/unit/test-crypto-hash.c | 7 ++++---
 tests/unit/test-crypto-hmac.c | 6 ++++--
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/tests/unit/test-crypto-hash.c b/tests/unit/test-crypto-hash.c
index e5829ca766..76c4699c15 100644
--- a/tests/unit/test-crypto-hash.c
+++ b/tests/unit/test-crypto-hash.c
@@ -123,7 +123,7 @@ static void test_hash_prealloc(void)
     size_t i;
 
     for (i = 0; i < G_N_ELEMENTS(expected_outputs) ; i++) {
-        uint8_t *result;
+        uint8_t *result, *origresult;
         size_t resultlen;
         int ret;
         size_t j;
@@ -133,7 +133,7 @@ static void test_hash_prealloc(void)
         }
 
         resultlen = expected_lens[i];
-        result = g_new0(uint8_t, resultlen);
+        origresult = result = g_new0(uint8_t, resultlen);
 
         ret = qcrypto_hash_bytes(i,
                                  INPUT_TEXT,
@@ -142,7 +142,8 @@ static void test_hash_prealloc(void)
                                  &resultlen,
                                  &error_fatal);
         g_assert(ret == 0);
-
+        /* Validate that our pre-allocated pointer was not replaced */
+        g_assert(result == origresult);
         g_assert(resultlen == expected_lens[i]);
         for (j = 0; j < resultlen; j++) {
             g_assert(expected_outputs[i][j * 2] == hex[(result[j] >> 4) & 0xf]);
diff --git a/tests/unit/test-crypto-hmac.c b/tests/unit/test-crypto-hmac.c
index 3fa50f24bb..cdb8774443 100644
--- a/tests/unit/test-crypto-hmac.c
+++ b/tests/unit/test-crypto-hmac.c
@@ -126,7 +126,7 @@ static void test_hmac_prealloc(void)
     for (i = 0; i < G_N_ELEMENTS(test_data); i++) {
         QCryptoHmacTestData *data = &test_data[i];
         QCryptoHmac *hmac = NULL;
-        uint8_t *result = NULL;
+        uint8_t *result = NULL, *origresult = NULL;
         size_t resultlen = 0;
         const char *exp_output = NULL;
         int ret;
@@ -139,7 +139,7 @@ static void test_hmac_prealloc(void)
         exp_output = data->hex_digest;
 
         resultlen = strlen(exp_output) / 2;
-        result = g_new0(uint8_t, resultlen);
+        origresult = result = g_new0(uint8_t, resultlen);
 
         hmac = qcrypto_hmac_new(data->alg, (const uint8_t *)KEY,
                                 strlen(KEY), &error_fatal);
@@ -149,6 +149,8 @@ static void test_hmac_prealloc(void)
                                  strlen(INPUT_TEXT), &result,
                                  &resultlen, &error_fatal);
         g_assert(ret == 0);
+        /* Validate that our pre-allocated pointer was not replaced */
+        g_assert(result == origresult);
 
         exp_output = data->hex_digest;
         for (j = 0; j < resultlen; j++) {
-- 
2.46.0