[SLOF] [PATCH v2 15/20] Add TPM firmware API call pass-through-to-tpm

[Stefan Berger]

From: Stefan Berger <stefanb at linux.vnet.ibm.com>

This patch adds support for the firmware API call pass-through-to-tpm.

Signed-off-by: Stefan Berger <stefanb at linux.vnet.ibm.com>
Reviewed-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
---
 board-qemu/slof/vio-vtpm-cdriver.fs |  8 ++++++++
 board-qemu/slof/vtpm-sml.fs         |  7 +++++++
 lib/libtpm/tcgbios.c                | 28 ++++++++++++++++++++++++++++
 lib/libtpm/tcgbios.h                |  1 +
 lib/libtpm/tpm.code                 | 11 +++++++++++
 lib/libtpm/tpm.in                   |  1 +
 slof/fs/tpm/tpm-static.fs           | 13 +++++++++++++
 7 files changed, 69 insertions(+)

diff --git a/board-qemu/slof/vio-vtpm-cdriver.fs b/board-qemu/slof/vio-vtpm-cdriver.fs
index fe84129..aaaac24 100644
--- a/board-qemu/slof/vio-vtpm-cdriver.fs
+++ b/board-qemu/slof/vio-vtpm-cdriver.fs
@@ -122,6 +122,14 @@ false VALUE vtpm-debug?
 ;
 
 \ firmware API call
+: pass-through-to-tpm ( buf-addr buf-size -- response-size )
+    " pass-through-to-tpm" vtpm-call-forward IF
+        2drop
+        0
+    THEN
+;
+
+\ firmware API call
 : get-maximum-cmd-size ( -- maximum-size )
     " get-maximum-cmd-size" vtpm-call-forward IF
         0
diff --git a/board-qemu/slof/vtpm-sml.fs b/board-qemu/slof/vtpm-sml.fs
index eb3dd6c..fcbd259 100644
--- a/board-qemu/slof/vtpm-sml.fs
+++ b/board-qemu/slof/vtpm-sml.fs
@@ -80,6 +80,13 @@ log-base LOG-SIZE tpm-set-log-parameters
     vtpm-get-maximum-cmd-size
 ;
 
+: pass-through-to-tpm ( buf-addr cmd-size -- rsp-size )
+    vtpm-debug? IF
+        ." Call to pass-through-to-tpm" cr
+    THEN
+    vtpm-pass-through-to-tpm
+;
+
 : open  true ;
 : close ;
 
diff --git a/lib/libtpm/tcgbios.c b/lib/libtpm/tcgbios.c
index 9231d46..05b3ccb 100644
--- a/lib/libtpm/tcgbios.c
+++ b/lib/libtpm/tcgbios.c
@@ -683,6 +683,34 @@ static bool pass_through_to_tpm(unsigned char *req,
 }
 
 /*
+ * tpm_pass_through_to_tpm: Function for interfacing with the firmware API
+ *
+ * buf: buffer holding the command; also used for holding the entire response
+ * cmdlen: length of the command in the buffer
+ *
+ * Returns 0 in case of failure, the size of the response otherwise.
+ */
+uint32_t tpm_pass_through_to_tpm(unsigned char *buf, uint32_t cmdlen)
+{
+	uint32_t resplen = PAPR_VTPM_MAX_BUFFER_SIZE;
+
+	/*
+	 * API spec: caller must ensure that the buffer is large
+	 *           enough to receive the full response into
+	 *           the same buffer where the command is in.
+	 *           We anticipate the largest possible buffer
+	 *           the driver supports in 'resplen'.
+	 * For duration we use the worst-case timeout 'LONG'
+	 * so that any command can be sent and will not time out.
+	 */
+	if (pass_through_to_tpm(buf, cmdlen,
+				TPM_DURATION_TYPE_LONG,
+				buf, &resplen))
+		return 0;
+	return resplen;
+}
+
+/*
  * Extend a PCR of the TPM with the given hash
  *
  * @hash: sha1 hash (20 bytes) to extend PCR with
diff --git a/lib/libtpm/tcgbios.h b/lib/libtpm/tcgbios.h
index 9ea772d..a91c6a3 100644
--- a/lib/libtpm/tcgbios.h
+++ b/lib/libtpm/tcgbios.h
@@ -42,6 +42,7 @@ uint32_t tpm_hash_log_extend_event(struct pcpes *pcpes);
 bool tpm_log_event(struct pcpes *pcpes);
 uint32_t tpm_hash_all(const void *data, uint32_t datalen, void *hashptr);
 uint32_t tpm_get_maximum_cmd_size(void);
+uint32_t tpm_pass_through_to_tpm(unsigned char *buf, uint32_t cmdlen);
 
 /* flags returned by tpm_get_state */
 #define TPM_STATE_ENABLED        1
diff --git a/lib/libtpm/tpm.code b/lib/libtpm/tpm.code
index b63b720..90015e7 100644
--- a/lib/libtpm/tpm.code
+++ b/lib/libtpm/tpm.code
@@ -174,3 +174,14 @@ PRIM(tpm_X2d_get_X2d_maximum_X2d_cmd_X2d_size)
 	PUSH;
 	TOS.n = tpm_get_maximum_cmd_size();
 MIRP
+
+/*******************************************************************/
+/* Firmware API                                                    */
+/* SLOF:   tpm-pass-through-to-tpm (buf-addr cmd-size -- rsp-size) */
+/* LIBTPM: respsize = tpm_pass_through_to_tpm(buf, cmdsize)        */
+/*******************************************************************/
+PRIM(tpm_X2d_pass_X2d_through_X2d_to_X2d_tpm)
+	int cmdsize = TOS.n; POP;
+	void *buf = TOS.a;
+	TOS.n = tpm_pass_through_to_tpm(buf, cmdsize);
+MIRP
diff --git a/lib/libtpm/tpm.in b/lib/libtpm/tpm.in
index e98c01e..93579ed 100644
--- a/lib/libtpm/tpm.in
+++ b/lib/libtpm/tpm.in
@@ -28,3 +28,4 @@ cod(tpm-log-event)
 cod(tpm-hash-log-extend-event)
 cod(tpm-hash-all)
 cod(tpm-get-maximum-cmd-size)
+cod(tpm-pass-through-to-tpm)
diff --git a/slof/fs/tpm/tpm-static.fs b/slof/fs/tpm/tpm-static.fs
index 7e353a0..b24d55d 100644
--- a/slof/fs/tpm/tpm-static.fs
+++ b/slof/fs/tpm/tpm-static.fs
@@ -124,6 +124,19 @@ false VALUE vtpm-debug?
     THEN
 ;
 
+\ firmware API function
+: vtpm-pass-through-to-tpm ( buf-addr cmd-size -- rsp-size )
+    vtpm-available? IF
+        tpm-pass-through-to-tpm                            ( -- rsp-size )
+        vtpm-debug? IF
+            ." VTPM: Return value from tpm-pass-through-to-tpm: " dup . cr
+        THEN
+    ELSE
+        2drop
+        0
+    THEN
+;
+
 1 CONSTANT TPM_ST_ENABLED
 2 CONSTANT TPM_ST_ACTIVE
 4 CONSTANT TPM_ST_OWNED
-- 
2.4.3