From 84556dd39531638ef69c8f1eec7f917de2c88146 Mon Sep 17 00:00:00 2001
From: Trammell hudson <hudson@trmm.net>
Date: Wed, 13 May 2020 12:00:14 +0200
Subject: [PATCH 1/6] tpm2_event_log: parse EV_POST_CODE events according to
2.3.4.1
Signed-off-by: Trammell hudson <hudson@trmm.net>
---
lib/tpm2_eventlog.c | 5 ++++-
lib/tpm2_eventlog_yaml.c | 24 ++++++++++++++++++++++++
2 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/lib/tpm2_eventlog.c b/lib/tpm2_eventlog.c
index b44ae10a9..b7bea6124 100644
--- a/lib/tpm2_eventlog.c
+++ b/lib/tpm2_eventlog.c
@@ -88,8 +88,11 @@ bool parse_event2body(TCG_EVENT2 const *event, UINT32 type) {
}
}
break;
- /* TCG PC Client FPF section 9.2.5 */
+ /* TCG PC Client FPF section 2.3.4.1 and 9.4.1 */
case EV_POST_CODE:
+ // the event is a string, so there are no length requirements.
+ break;
+ /* TCG PC Client FPF section 9.2.5 */
case EV_S_CRTM_CONTENTS:
case EV_EFI_PLATFORM_FIRMWARE_BLOB:
{
diff --git a/lib/tpm2_eventlog_yaml.c b/lib/tpm2_eventlog_yaml.c
index 307c4a09d..ae1406bfe 100644
--- a/lib/tpm2_eventlog_yaml.c
+++ b/lib/tpm2_eventlog_yaml.c
@@ -164,6 +164,29 @@ static bool yaml_uefi_var_data(UEFI_VARIABLE_DATA *data) {
return true;
}
+/*
+ * TCG PC Client FPF section 2.3.4.1 and 9.4.1:
+ * Usage of the event type EV_POST_CODE:
+ * - If a combined event is measured, the event field SHOULD
+ * be the string "POST CODE" in all caps. ...
+ * - Embedded SMM code and the code that sets it up SHOULD use
+ * the string "SMM CODE" in all caps...
+ * - BIS code (eclusing the BIS Certificate) should use event
+ * field string of "BIS CODE" in all caps. ...
+ * - ACPI flash data prior to any modifications ... should use
+ * event field string of "ACPI DATA" in all caps.
+ */
+static bool yaml_uefi_post_code(const char * data, size_t len)
+{
+ tpm2_tool_output(
+ " Event:\n"
+ " - Length: %zu\n"
+ " String: '%.*s'\n",
+ len,
+ (int) len,
+ data);
+ return true;
+}
/*
* TCG PC Client FPF section 9.2.6
* The tpm2_eventlog module validates the event structure but nothing within
@@ -247,6 +270,7 @@ bool yaml_event2data(TCG_EVENT2 const *event, UINT32 type) {
case EV_EFI_VARIABLE_AUTHORITY:
return yaml_uefi_var((UEFI_VARIABLE_DATA*)event->Event);
case EV_POST_CODE:
+ return yaml_uefi_post_code((const char*)event->Event, event->EventSize);
case EV_S_CRTM_CONTENTS:
case EV_EFI_PLATFORM_FIRMWARE_BLOB:
return yaml_uefi_platfwblob((UEFI_PLATFORM_FIRMWARE_BLOB*)event->Event);
From abfae7af25bdbb41709d09bf99a01132f2f3c24e Mon Sep 17 00:00:00 2001
From: Trammell hudson <hudson@trmm.net>
Date: Wed, 13 May 2020 12:04:49 +0200
Subject: [PATCH 2/6] tpm2_eventlog: rename postcode test to firmware blob test
Signed-off-by: Trammell hudson <hudson@trmm.net>
---
test/unit/test_tpm2_eventlog.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/test/unit/test_tpm2_eventlog.c b/test/unit/test_tpm2_eventlog.c
index e992ac848..661778506 100644
--- a/test/unit/test_tpm2_eventlog.c
+++ b/test/unit/test_tpm2_eventlog.c
@@ -266,7 +266,7 @@ static void test_parse_event2body_uefivar_badlength(void **state){
assert_false(parse_event2body(event, EV_EFI_VARIABLE_DRIVER_CONFIG));
}
-static void test_parse_event2body_postcode_badlength(void **state){
+static void test_parse_event2body_firmware_blob_badlength(void **state){
(void)state;
@@ -465,7 +465,7 @@ int main(void) {
cmocka_unit_test(test_foreach_event2_parse_event2body_fail),
cmocka_unit_test(test_parse_event2body_uefivar_badsize),
cmocka_unit_test(test_parse_event2body_uefivar_badlength),
- cmocka_unit_test(test_parse_event2body_postcode_badlength),
+ cmocka_unit_test(test_parse_event2body_firmware_blob_badlength),
cmocka_unit_test(test_specid_event_nohdr),
cmocka_unit_test(test_specid_event_badeventtype),
cmocka_unit_test(test_specid_event_badpcrindex),
From de84d5bd6f89bded62e8dc0ae57619a3758920e5 Mon Sep 17 00:00:00 2001
From: Trammell hudson <hudson@trmm.net>
Date: Wed, 13 May 2020 12:09:45 +0200
Subject: [PATCH 3/6] tpm2_eventlog: pass TCG_EVENT2* to yaml-Uefi_post_code()
Signed-off-by: Trammell hudson <hudson@trmm.net>
---
lib/tpm2_eventlog_yaml.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/lib/tpm2_eventlog_yaml.c b/lib/tpm2_eventlog_yaml.c
index ae1406bfe..e9092769d 100644
--- a/lib/tpm2_eventlog_yaml.c
+++ b/lib/tpm2_eventlog_yaml.c
@@ -171,13 +171,16 @@ static bool yaml_uefi_var_data(UEFI_VARIABLE_DATA *data) {
* be the string "POST CODE" in all caps. ...
* - Embedded SMM code and the code that sets it up SHOULD use
* the string "SMM CODE" in all caps...
- * - BIS code (eclusing the BIS Certificate) should use event
+ * - BIS code (excluding the BIS Certificate) should use event
* field string of "BIS CODE" in all caps. ...
* - ACPI flash data prior to any modifications ... should use
* event field string of "ACPI DATA" in all caps.
*/
-static bool yaml_uefi_post_code(const char * data, size_t len)
+static bool yaml_uefi_post_code(const TCG_EVENT2 * const event)
{
+ const char * const data = (const char *) event->Event;
+ const size_t len = event->EventSize;
+
tpm2_tool_output(
" Event:\n"
" - Length: %zu\n"
@@ -270,7 +273,7 @@ bool yaml_event2data(TCG_EVENT2 const *event, UINT32 type) {
case EV_EFI_VARIABLE_AUTHORITY:
return yaml_uefi_var((UEFI_VARIABLE_DATA*)event->Event);
case EV_POST_CODE:
- return yaml_uefi_post_code((const char*)event->Event, event->EventSize);
+ return yaml_uefi_post_code(event);
case EV_S_CRTM_CONTENTS:
case EV_EFI_PLATFORM_FIRMWARE_BLOB:
return yaml_uefi_platfwblob((UEFI_PLATFORM_FIRMWARE_BLOB*)event->Event);
From dddeb4d3bc2e4d1eddf143a1ee70de7f7f32fbf3 Mon Sep 17 00:00:00 2001
From: Trammell hudson <hudson@trmm.net>
Date: Wed, 13 May 2020 12:55:14 +0200
Subject: [PATCH 4/6] tpm2_eventlog: use "PCRIndex:" consistently
Signed-off-by: Trammell hudson <hudson@trmm.net>
---
lib/tpm2_eventlog_yaml.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/tpm2_eventlog_yaml.c b/lib/tpm2_eventlog_yaml.c
index e9092769d..d1f308904 100644
--- a/lib/tpm2_eventlog_yaml.c
+++ b/lib/tpm2_eventlog_yaml.c
@@ -329,7 +329,7 @@ void yaml_eventhdr(TCG_EVENT const *event, size_t *count) {
bytes_to_str(event->digest, sizeof(event->digest), digest_hex, sizeof(digest_hex));
tpm2_tool_output("- Event[%zu]:\n"
- " pcrIndex: %" PRIu32 "\n"
+ " PCRIndex: %" PRIu32 "\n"
" eventType: %s\n"
" digest: %s\n"
" eventDataSize: %" PRIu32 "\n", (*count)++, event->pcrIndex,
From c56c70f62af9a4fe884c6efa69eeb36f39d6fe65 Mon Sep 17 00:00:00 2001
From: Trammell hudson <hudson@trmm.net>
Date: Wed, 13 May 2020 12:58:20 +0200
Subject: [PATCH 5/6] tpm2_eventlog: use "Digest:" and "EventSize:"
consistently
Signed-off-by: Trammell hudson <hudson@trmm.net>
---
lib/tpm2_eventlog_yaml.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/lib/tpm2_eventlog_yaml.c b/lib/tpm2_eventlog_yaml.c
index d1f308904..50bd2fa6d 100644
--- a/lib/tpm2_eventlog_yaml.c
+++ b/lib/tpm2_eventlog_yaml.c
@@ -330,9 +330,9 @@ void yaml_eventhdr(TCG_EVENT const *event, size_t *count) {
tpm2_tool_output("- Event[%zu]:\n"
" PCRIndex: %" PRIu32 "\n"
- " eventType: %s\n"
- " digest: %s\n"
- " eventDataSize: %" PRIu32 "\n", (*count)++, event->pcrIndex,
+ " EventType: %s\n"
+ " Digest: %s\n"
+ " EventSize: %" PRIu32 "\n", (*count)++, event->pcrIndex,
eventtype_to_string(event->eventType), digest_hex,
event->eventDataSize);
}
From 113ab8c213418c6d1c9045bb19069159cc5b594b Mon Sep 17 00:00:00 2001
From: Trammell hudson <hudson@trmm.net>
Date: Wed, 13 May 2020 14:16:39 +0200
Subject: [PATCH 6/6] tpm2_eventlog: use same output format for EV_EFI_ACTION
and EV_POST_CODE
This also avoids a potential stack smash if the event log
violates the spec and has an action string longer than
permitted.
Signed-off-by: Trammell hudson <hudson@trmm.net>
---
lib/tpm2_eventlog_yaml.c | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/lib/tpm2_eventlog_yaml.c b/lib/tpm2_eventlog_yaml.c
index 50bd2fa6d..8966cae42 100644
--- a/lib/tpm2_eventlog_yaml.c
+++ b/lib/tpm2_eventlog_yaml.c
@@ -182,10 +182,7 @@ static bool yaml_uefi_post_code(const TCG_EVENT2 * const event)
const size_t len = event->EventSize;
tpm2_tool_output(
- " Event:\n"
- " - Length: %zu\n"
- " String: '%.*s'\n",
- len,
+ " Event: '%.*s'\n",
(int) len,
data);
return true;
@@ -225,11 +222,7 @@ bool yaml_uefi_platfwblob(UEFI_PLATFORM_FIRMWARE_BLOB *data) {
/* TCG PC Client PFP section 9.4.4 */
bool yaml_uefi_action(UINT8 const *action, size_t size) {
- /* longest string permitted by spec is 47 chars */
- char buf[50] = { '\0', };
-
- memcpy (buf, action, size);
- tpm2_tool_output(" Event: %s\n", buf);
+ tpm2_tool_output(" Event: '%.*s'\n", (int) size, action);
return true;
}