[SLOF] [PATCH v4 13/33] tpm: Add TPM firmware API call pass-through-to-tpm
Stefan Berger
stefanb at linux.vnet.ibm.com
Thu Dec 12 07:27:08 AEDT 2019
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 | 10 ++++++
lib/libtpm/tcgbios.c | 52 +++++++++++++++++++++++++++++
lib/libtpm/tcgbios.h | 1 +
lib/libtpm/tpm.code | 11 ++++++
lib/libtpm/tpm.in | 1 +
lib/libtpm/tpm_drivers.h | 3 ++
7 files changed, 86 insertions(+)
diff --git a/board-qemu/slof/vio-vtpm-cdriver.fs b/board-qemu/slof/vio-vtpm-cdriver.fs
index de69e2d..0699c4d 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?
THEN
;
+\ 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
diff --git a/board-qemu/slof/vtpm-sml.fs b/board-qemu/slof/vtpm-sml.fs
index bf0d55e..c51765b 100644
--- a/board-qemu/slof/vtpm-sml.fs
+++ b/board-qemu/slof/vtpm-sml.fs
@@ -94,6 +94,16 @@ log-base LOG-SIZE tpm-set-log-parameters
THEN
;
+: pass-through-to-tpm ( buf-addr cmd-size -- rsp-size )
+ vtpm-debug? IF
+ ." Call to pass-through-to-tpm" cr
+ THEN
+ tpm-pass-through-to-tpm ( rsp-size )
+ vtpm-debug? IF
+ ." VTPM: Return value from tpm-pass-through-to-tpm: " dup . cr
+ THEN
+;
+
\
\ internal API calls
\
diff --git a/lib/libtpm/tcgbios.c b/lib/libtpm/tcgbios.c
index 9114d64..38fa545 100644
--- a/lib/libtpm/tcgbios.c
+++ b/lib/libtpm/tcgbios.c
@@ -837,3 +837,55 @@ uint32_t tpm_get_maximum_cmd_size(void)
return MIN(cpu_to_be32(trgb.buffersize),
spapr_vtpm_get_buffersize());
}
+
+static bool pass_through_to_tpm(unsigned char *req,
+ uint32_t reqlen,
+ enum tpm_duration_type to_t,
+ unsigned char *rsp,
+ uint32_t *rsplen)
+{
+ struct tpm_req_header *trqh;
+ int ret;
+
+ if (!tpm_is_working())
+ return TCGBIOS_FATAL_COM_ERROR;
+
+ trqh = (struct tpm_req_header *)req;
+ if (reqlen < sizeof(*trqh))
+ return TCGBIOS_INVALID_INPUT_PARA;
+
+ ret = tpmhw_transmit(0, trqh, rsp, rsplen, to_t);
+ if (ret)
+ return TCGBIOS_FATAL_COM_ERROR;
+
+ return 0;
+}
+
+/*
+ * 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;
+}
diff --git a/lib/libtpm/tcgbios.h b/lib/libtpm/tcgbios.h
index 6eb6751..5beaa53 100644
--- a/lib/libtpm/tcgbios.h
+++ b/lib/libtpm/tcgbios.h
@@ -35,6 +35,7 @@ uint32_t tpm_measure_bcv_mbr(uint32_t bootdrv, const uint8_t *addr,
uint32_t tpm_add_event_separators(uint32_t start_pcr, uint32_t end_pcr);
uint32_t tpm_process_opcode(uint8_t op, bool verbose);
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 ecfba8c..adf1f01 100644
--- a/lib/libtpm/tpm.code
+++ b/lib/libtpm/tpm.code
@@ -172,3 +172,14 @@ 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 1bd393e..f0c92e2 100644
--- a/lib/libtpm/tpm.in
+++ b/lib/libtpm/tpm.in
@@ -28,3 +28,4 @@ cod(tpm-get-state)
cod(tpm-is-working)
cod(tpm-measure-scrtm)
cod(tpm-get-maximum-cmd-size)
+cod(tpm-pass-through-to-tpm)
diff --git a/lib/libtpm/tpm_drivers.h b/lib/libtpm/tpm_drivers.h
index ab2e152..96bd32d 100644
--- a/lib/libtpm/tpm_drivers.h
+++ b/lib/libtpm/tpm_drivers.h
@@ -70,6 +70,9 @@ typedef enum {
VTPM_DRV_ERROR_SML_HANDED_OVER = 14,
} vtpm_drv_error;
+/* the max. buffer size by the external TPM is 4k */
+#define PAPR_VTPM_MAX_BUFFER_SIZE 4096
+
/* exported functions */
bool spapr_is_vtpm_present(void);
void spapr_vtpm_finalize(void);
--
2.17.1
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