From: "Daniel P. Smith" <dpsm...@apertussolutions.com>

This commit exposes a minimal general interface for the compressed
kernel to request the required TPM operations to send measurements to
a TPM.

Signed-off-by: Daniel P. Smith <dpsm...@apertussolutions.com>
Signed-off-by: Ross Philipson <ross.philip...@oracle.com>
---
 arch/x86/boot/compressed/Makefile  |   2 +-
 arch/x86/boot/compressed/tpm/tpm.c | 145 +++++++++++++++++++++++++++++++++++++
 2 files changed, 146 insertions(+), 1 deletion(-)
 create mode 100644 arch/x86/boot/compressed/tpm/tpm.c

diff --git a/arch/x86/boot/compressed/Makefile 
b/arch/x86/boot/compressed/Makefile
index a4308d5..35947b9 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -101,7 +101,7 @@ vmlinux-objs-$(CONFIG_SECURE_LAUNCH_SHA256) += 
$(obj)/early_sha256.o
 vmlinux-objs-$(CONFIG_SECURE_LAUNCH_SHA512) += $(obj)/early_sha512.o
 vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/tpm/tpmio.o 
$(obj)/tpm/tpm_buff.o \
        $(obj)/tpm/tis.o $(obj)/tpm/crb.o $(obj)/tpm/tpm1_cmds.o \
-       $(obj)/tpm/tpm2_cmds.o $(obj)/tpm/tpm2_auth.o
+       $(obj)/tpm/tpm2_cmds.o $(obj)/tpm/tpm2_auth.o $(obj)/tpm/tpm.o
 
 # The compressed kernel is built with -fPIC/-fPIE so that a boot loader
 # can place it anywhere in memory and it will still run. However, since
diff --git a/arch/x86/boot/compressed/tpm/tpm.c 
b/arch/x86/boot/compressed/tpm/tpm.c
new file mode 100644
index 0000000..0fe62d2
--- /dev/null
+++ b/arch/x86/boot/compressed/tpm/tpm.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020 Apertus Solutions, LLC
+ *
+ * Author(s):
+ *      Daniel P. Smith <dpsm...@apertussolutions.com>
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/const.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include "tpm.h"
+#include "tpmbuff.h"
+#include "tis.h"
+#include "crb.h"
+#include "tpm_common.h"
+#include "tpm1.h"
+#include "tpm2.h"
+#include "tpm2_constants.h"
+
+static struct tpm tpm;
+
+static void find_interface_and_family(struct tpm *t)
+{
+       struct tpm_interface_id intf_id;
+       struct tpm_intf_capability intf_cap;
+
+       /* Sort out whether if it is 1.2 */
+       intf_cap.val = tpm_read32(TPM_INTF_CAPABILITY_0);
+       if ((intf_cap.interface_version == TPM12_TIS_INTF_12) ||
+           (intf_cap.interface_version == TPM12_TIS_INTF_13)) {
+               t->family = TPM12;
+               t->intf = TPM_TIS;
+               return;
+       }
+
+       /* Assume that it is 2.0 and TIS */
+       t->family = TPM20;
+       t->intf = TPM_TIS;
+
+       /* Check if the interface is CRB */
+       intf_id.val = tpm_read32(TPM_INTERFACE_ID_0);
+       if (intf_id.interface_type == TPM_CRB_INTF_ACTIVE)
+               t->intf = TPM_CRB;
+}
+
+struct tpm *enable_tpm(void)
+{
+       struct tpm *t = &tpm;
+
+       find_interface_and_family(t);
+
+       switch (t->intf) {
+       case TPM_TIS:
+               if (!tis_init(t))
+                       return NULL;
+               break;
+       case TPM_CRB:
+               if (!crb_init(t))
+                       return NULL;
+               break;
+       }
+
+       return t;
+}
+
+u8 tpm_request_locality(struct tpm *t, u8 l)
+{
+       u8 ret = TPM_NO_LOCALITY;
+
+       ret = t->ops.request_locality(l);
+
+       if (ret < TPM_MAX_LOCALITY)
+               t->buff = alloc_tpmbuff(t->intf, ret);
+
+       return ret;
+}
+
+void tpm_relinquish_locality(struct tpm *t)
+{
+       t->ops.relinquish_locality();
+
+       free_tpmbuff(t->buff, t->intf);
+}
+
+#define MAX_TPM_EXTEND_SIZE 70 /* TPM2 SHA512 is the largest */
+int tpm_extend_pcr(struct tpm *t, u32 pcr, u16 algo,
+               u8 *digest)
+{
+       int ret = 0;
+
+       if (t->buff == NULL)
+               return -EINVAL;
+
+       if (t->family == TPM12) {
+               struct tpm_digest d;
+
+               if (algo != TPM_ALG_SHA1)
+                       return -EINVAL;
+
+               d.pcr = pcr;
+               memcpy((void *)d.digest.sha1.digest,
+                       digest, SHA1_DIGEST_SIZE);
+
+               ret = tpm1_pcr_extend(t, &d);
+       } else if (t->family == TPM20) {
+               struct tpml_digest_values *d;
+               u8 buf[MAX_TPM_EXTEND_SIZE];
+
+               d = (struct tpml_digest_values *) buf;
+               d->count = 1;
+               d->digests->alg = algo;
+               switch (algo) {
+               case TPM_ALG_SHA1:
+                       memcpy(d->digests->digest, digest, SHA1_SIZE);
+                       break;
+               case TPM_ALG_SHA256:
+                       memcpy(d->digests->digest, digest, SHA256_SIZE);
+                       break;
+               case TPM_ALG_SHA384:
+                       memcpy(d->digests->digest, digest, SHA384_SIZE);
+                       break;
+               case TPM_ALG_SHA512:
+                       memcpy(d->digests->digest, digest, SHA512_SIZE);
+                       break;
+               case TPM_ALG_SM3_256:
+                       memcpy(d->digests->digest, digest, SM3256_SIZE);
+                       break;
+               default:
+                       return -EINVAL;
+               }
+
+               ret = tpm2_extend_pcr(t, pcr, d);
+       } else
+               ret = -EINVAL;
+
+       return ret;
+}
+
+void free_tpm(struct tpm *t)
+{
+       tpm_relinquish_locality(t);
+}
-- 
1.8.3.1

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