[PATCH 2/2] tests: Skip over first 14 bytes when comparing TPM PCRRead result

[Stefan Berger <stefanb@linux.vnet.ibm.com>]

Due to a change in the TPM 2 code the pcrUpdate counter in the
PCRRead response is now different. The easiest way is to skip over
the first 14 bytes and only compare the tail of the response.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
 tests/qtest/tpm-tests.c | 6 +++---
 tests/qtest/tpm-util.c  | 6 ++++--
 tests/qtest/tpm-util.h  | 3 ++-
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/tests/qtest/tpm-tests.c b/tests/qtest/tpm-tests.c
index a2f2838e15..8f6491a4b7 100644
--- a/tests/qtest/tpm-tests.c
+++ b/tests/qtest/tpm-tests.c
@@ -65,7 +65,7 @@ void tpm_test_swtpm_test(const char *src_tpm_path, tx_func *tx,
         "\x98\xe5\x86\x8d\xe6\x8b\x97\x29\x99\x60\xf2\x71\x7d\x17\x67\x89"
         "\xa4\x2f\x9a\xae\xa8\xc7\xb7\xaa\x79\xa8\x62\x56\xc1\xde";
     tpm_util_pcrread(s, tx, tpm_pcrread_resp,
-                     sizeof(tpm_pcrread_resp));
+                     sizeof(tpm_pcrread_resp), 14);
 
     qtest_end();
     tpm_util_swtpm_kill(swtpm_pid);
@@ -113,13 +113,13 @@ void tpm_test_swtpm_migration_test(const char *src_tpm_path,
         "\x98\xe5\x86\x8d\xe6\x8b\x97\x29\x99\x60\xf2\x71\x7d\x17\x67\x89"
         "\xa4\x2f\x9a\xae\xa8\xc7\xb7\xaa\x79\xa8\x62\x56\xc1\xde";
     tpm_util_pcrread(src_qemu, tx, tpm_pcrread_resp,
-                     sizeof(tpm_pcrread_resp));
+                     sizeof(tpm_pcrread_resp), 14);
 
     tpm_util_migrate(src_qemu, uri);
     tpm_util_wait_for_migration_complete(src_qemu);
 
     tpm_util_pcrread(dst_qemu, tx, tpm_pcrread_resp,
-                     sizeof(tpm_pcrread_resp));
+                     sizeof(tpm_pcrread_resp), 14);
 
     qtest_quit(dst_qemu);
     qtest_quit(src_qemu);
diff --git a/tests/qtest/tpm-util.c b/tests/qtest/tpm-util.c
index 34efae8f18..df85e23432 100644
--- a/tests/qtest/tpm-util.c
+++ b/tests/qtest/tpm-util.c
@@ -130,7 +130,8 @@ void tpm_util_pcrextend(QTestState *s, tx_func *tx)
 }
 
 void tpm_util_pcrread(QTestState *s, tx_func *tx,
-                      const unsigned char *exp_resp, size_t exp_resp_size)
+                      const unsigned char *exp_resp, size_t exp_resp_size,
+                      off_t offset)
 {
     unsigned char buffer[1024];
     unsigned char tpm_pcrread[] =
@@ -139,7 +140,8 @@ void tpm_util_pcrread(QTestState *s, tx_func *tx,
 
     tx(s, tpm_pcrread, sizeof(tpm_pcrread), buffer, sizeof(buffer));
 
-    g_assert_cmpmem(buffer, exp_resp_size, exp_resp, exp_resp_size);
+    g_assert_cmpmem(&buffer[offset], exp_resp_size - offset,
+                    &exp_resp[offset], exp_resp_size - offset);
 }
 
 bool tpm_util_swtpm_has_tpm2(void)
diff --git a/tests/qtest/tpm-util.h b/tests/qtest/tpm-util.h
index 3b97d69017..d6f4c17218 100644
--- a/tests/qtest/tpm-util.h
+++ b/tests/qtest/tpm-util.h
@@ -34,7 +34,8 @@ void tpm_util_tis_transfer(QTestState *s,
 void tpm_util_startup(QTestState *s, tx_func *tx);
 void tpm_util_pcrextend(QTestState *s, tx_func *tx);
 void tpm_util_pcrread(QTestState *s, tx_func *tx,
-                      const unsigned char *exp_resp, size_t exp_resp_size);
+                      const unsigned char *exp_resp, size_t exp_resp_size,
+                      off_t offset);
 
 bool tpm_util_swtpm_has_tpm2(void);
 
-- 
2.24.1