[SeaBIOS] [RFC PATCH v1 4/9] tpm: Implement tpm2_startup and tpm2_s3_resume

[Stefan Berger]

From: Stefan Berger

Implement tpm2_startup and tpm2_s3_resume and their dependencies.

We follow this specification:

TCG PC Client Specific Platform Firmware Profile for TPM 2.0 Systems Revision 1.0 Version 21

It can be found on this page:

http://www.trustedcomputinggroup.org/resources/specifications_in_public_revi...

Power on: Figure 7 & 7.3.2 item 4.
S3: Figure 9 & 7.3.2 item 4.

Signed-off-by: Stefan Berger 
---
 src/std/tcg.h | 20 ++++++++++++++++
 src/tcgbios.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 91 insertions(+), 6 deletions(-)

diff --git a/src/std/tcg.h b/src/std/tcg.h
index 91692e9..db1155d 100644
--- a/src/std/tcg.h
+++ b/src/std/tcg.h
@@ -362,4 +362,24 @@ struct tpm_res_sha1complete {
 #define TPM_PPI_OP_SET_OWNERINSTALL_TRUE 8
 #define TPM_PPI_OP_SET_OWNERINSTALL_FALSE 9

+/*
+ * TPM 2
+ */
+
+#define TPM2_NO                     0
+#define TPM2_YES                    1
+
+#define TPM2_SU_CLEAR               0x0000
+#define TPM2_SU_STATE               0x0001
+
+/* TPM 2 command tags */
+#define TPM2_ST_NO_SESSIONS         0x8001
+
+/* TPM 2 commands */
+#define TPM2_CC_SelfTest            0x143
+#define TPM2_CC_Startup             0x144
+
+/* TPM 2 error codes */
+#define TPM2_RC_INITIALIZE          0x100
+
 #endif // tcg.h
diff --git a/src/tcgbios.c b/src/tcgbios.c
index 89af876..0d6cfdb 100644
--- a/src/tcgbios.c
+++ b/src/tcgbios.c
@@ -25,6 +25,10 @@
 #include "util.h" // printf, get_keystroke
 #include "stacks.h" // wait_threads, reset

+/****************************************************************
+ * TPM 1.2 commands
+ ****************************************************************/
+
 static const u8 Startup_ST_CLEAR[] = { 0x00, TPM_ST_CLEAR };
 static const u8 Startup_ST_STATE[] = { 0x00, TPM_ST_STATE };

@@ -36,8 +40,17 @@ static const u8 PhysicalPresence_NOT_PRESENT_LOCK[] = { 0x00, 0x14 };
 static const u8 CommandFlag_FALSE[1] = { 0x00 };
 static const u8 CommandFlag_TRUE[1]  = { 0x01 };

-typedef u8 tpm_ppi_code;
+/****************************************************************
+ * TPM 2 commands
+ ****************************************************************/
+
+static const u8 Startup_SU_CLEAR[] = { 0x00, TPM2_SU_CLEAR};
+static const u8 Startup_SU_STATE[] = { 0x00, TPM2_SU_STATE};

+static const u8 TPM2_SelfTest_YES[] =  { TPM2_YES }; /* full test */
+
+
+typedef u8 tpm_ppi_code;

/****************************************************************
  * ACPI TCPA table interface
@@ -191,12 +204,22 @@ tpm_build_and_send_cmd(u8 locty, u32 ordinal, const u8 *append,
 {
     struct {
         struct tpm_req_header trqh;
-        u8 cmd[2];
+        u8 cmd[6];
     } PACKED req = {
         .trqh.tag = cpu_to_be16(TPM_TAG_RQU_CMD),
         .trqh.totlen = cpu_to_be32(sizeof(req.trqh) + append_size),
         .trqh.ordinal = cpu_to_be32(ordinal),
     };
+
+    switch (TPM_version) {
+    case TPM_VERSION_1_2:
+        req.trqh.tag = cpu_to_be16(TPM_TAG_RQU_CMD);
+        break;
+    case TPM_VERSION_2:
+        req.trqh.tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+        break;
+    }
+
     u8 obuffer[64];
     struct tpm_rsp_header *trsh = (struct tpm_rsp_header *)obuffer;
     u32 obuffer_len = sizeof(obuffer);
@@ -532,14 +555,47 @@ err_exit:
 }

static int
+tpm2_startup(void)
+{
+    dprintf(DEBUG_tcg, "TCGBIOS: Starting with TPM2_Startup(SU_CLEAR)\n");
+    int ret = tpm_build_and_send_cmd(0, TPM2_CC_Startup,
+                                     Startup_SU_CLEAR,
+                                     sizeof(Startup_SU_CLEAR),
+                                     TPM_DURATION_TYPE_SHORT);
+
+    if (CONFIG_COREBOOT && ret == TPM2_RC_INITIALIZE)
+        /* with other firmware on the system the TPM may already have been
+         * initialized
+         */
+        ret = 0;
+
+    if (ret)
+        goto err_exit;
+
+    ret = tpm_build_and_send_cmd(0, TPM2_CC_SelfTest,
+                                 TPM2_SelfTest_YES,
+                                 sizeof(TPM2_SelfTest_YES),
+                                 TPM_DURATION_TYPE_LONG);
+    if (ret)
+        goto err_exit;
+
+    return 0;
+
+err_exit:
+    dprintf(DEBUG_tcg, "TCGBIOS: TPM malfunctioning (line %d).\n", __LINE__);
+
+    tpm_set_failure();
+    return -1;
+}
+
+static int
 tpm_startup(void)
 {
     switch (TPM_version) {
     case TPM_VERSION_1_2:
         return tpm12_startup();
     case TPM_VERSION_2:
-        // FIXME: missing code
-        return -1;
+        return tpm2_startup();
     }

return -1;
@@ -697,8 +753,17 @@ tpm_s3_resume(void)
                                      TPM_DURATION_TYPE_SHORT);
         break;
     case TPM_VERSION_2:
-        // FIXME: missing code
-        ret = -1;
+        ret = tpm_build_and_send_cmd(0, TPM2_CC_Startup,
+                                     Startup_SU_STATE,
+                                     sizeof(Startup_SU_STATE),
+                                     TPM_DURATION_TYPE_SHORT);
+        if (ret)
+            goto err_exit;
+
+
+        ret = tpm_build_and_send_cmd(0, TPM2_CC_SelfTest,
+                                     TPM2_SelfTest_YES, sizeof(TPM2_SelfTest_YES),
+                                     TPM_DURATION_TYPE_LONG);
         break;
     }