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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/char/tpm/tpm-interface.c
Initial import
Diffstat (limited to 'drivers/char/tpm/tpm-interface.c')
-rw-r--r--drivers/char/tpm/tpm-interface.c1056
1 files changed, 1056 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
new file mode 100644
index 000000000..e85d3416d
--- /dev/null
+++ b/drivers/char/tpm/tpm-interface.c
@@ -0,0 +1,1056 @@
+/*
+ * Copyright (C) 2004 IBM Corporation
+ * Copyright (C) 2014 Intel Corporation
+ *
+ * Authors:
+ * Leendert van Doorn <leendert@watson.ibm.com>
+ * Dave Safford <safford@watson.ibm.com>
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * Device driver for TCG/TCPA TPM (trusted platform module).
+ * Specifications at www.trustedcomputinggroup.org
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ * Note, the TPM chip is not interrupt driven (only polling)
+ * and can have very long timeouts (minutes!). Hence the unusual
+ * calls to msleep.
+ *
+ */
+
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/freezer.h>
+
+#include "tpm.h"
+#include "tpm_eventlog.h"
+
+#define TPM_MAX_ORDINAL 243
+#define TSC_MAX_ORDINAL 12
+#define TPM_PROTECTED_COMMAND 0x00
+#define TPM_CONNECTION_COMMAND 0x40
+
+/*
+ * Bug workaround - some TPM's don't flush the most
+ * recently changed pcr on suspend, so force the flush
+ * with an extend to the selected _unused_ non-volatile pcr.
+ */
+static int tpm_suspend_pcr;
+module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
+MODULE_PARM_DESC(suspend_pcr,
+ "PCR to use for dummy writes to faciltate flush on suspend.");
+
+/*
+ * Array with one entry per ordinal defining the maximum amount
+ * of time the chip could take to return the result. The ordinal
+ * designation of short, medium or long is defined in a table in
+ * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
+ * values of the SHORT, MEDIUM, and LONG durations are retrieved
+ * from the chip during initialization with a call to tpm_get_timeouts.
+ */
+static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
+ TPM_UNDEFINED, /* 0 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 5 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 10 */
+ TPM_SHORT,
+ TPM_MEDIUM,
+ TPM_LONG,
+ TPM_LONG,
+ TPM_MEDIUM, /* 15 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_MEDIUM,
+ TPM_LONG,
+ TPM_SHORT, /* 20 */
+ TPM_SHORT,
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_SHORT, /* 25 */
+ TPM_SHORT,
+ TPM_MEDIUM,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_MEDIUM, /* 30 */
+ TPM_LONG,
+ TPM_MEDIUM,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT, /* 35 */
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_MEDIUM, /* 40 */
+ TPM_LONG,
+ TPM_MEDIUM,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT, /* 45 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_LONG,
+ TPM_MEDIUM, /* 50 */
+ TPM_MEDIUM,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 55 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_MEDIUM, /* 60 */
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_MEDIUM, /* 65 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 70 */
+ TPM_SHORT,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 75 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_LONG, /* 80 */
+ TPM_UNDEFINED,
+ TPM_MEDIUM,
+ TPM_LONG,
+ TPM_SHORT,
+ TPM_UNDEFINED, /* 85 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 90 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_UNDEFINED, /* 95 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_MEDIUM, /* 100 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 105 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 110 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT, /* 115 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_LONG, /* 120 */
+ TPM_LONG,
+ TPM_MEDIUM,
+ TPM_UNDEFINED,
+ TPM_SHORT,
+ TPM_SHORT, /* 125 */
+ TPM_SHORT,
+ TPM_LONG,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT, /* 130 */
+ TPM_MEDIUM,
+ TPM_UNDEFINED,
+ TPM_SHORT,
+ TPM_MEDIUM,
+ TPM_UNDEFINED, /* 135 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 140 */
+ TPM_SHORT,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 145 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 150 */
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_UNDEFINED, /* 155 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 160 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 165 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_LONG, /* 170 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 175 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_MEDIUM, /* 180 */
+ TPM_SHORT,
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_MEDIUM, /* 185 */
+ TPM_SHORT,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 190 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 195 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 200 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT,
+ TPM_SHORT, /* 205 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_MEDIUM, /* 210 */
+ TPM_UNDEFINED,
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_MEDIUM,
+ TPM_UNDEFINED, /* 215 */
+ TPM_MEDIUM,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT,
+ TPM_SHORT, /* 220 */
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_SHORT,
+ TPM_UNDEFINED, /* 225 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 230 */
+ TPM_LONG,
+ TPM_MEDIUM,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED, /* 235 */
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_UNDEFINED,
+ TPM_SHORT, /* 240 */
+ TPM_UNDEFINED,
+ TPM_MEDIUM,
+};
+
+/*
+ * Returns max number of jiffies to wait
+ */
+unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
+ u32 ordinal)
+{
+ int duration_idx = TPM_UNDEFINED;
+ int duration = 0;
+ u8 category = (ordinal >> 24) & 0xFF;
+
+ if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) ||
+ (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL))
+ duration_idx = tpm_ordinal_duration[ordinal];
+
+ if (duration_idx != TPM_UNDEFINED)
+ duration = chip->vendor.duration[duration_idx];
+ if (duration <= 0)
+ return 2 * 60 * HZ;
+ else
+ return duration;
+}
+EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+
+/*
+ * Internal kernel interface to transmit TPM commands
+ */
+ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
+ size_t bufsiz)
+{
+ ssize_t rc;
+ u32 count, ordinal;
+ unsigned long stop;
+
+ if (bufsiz > TPM_BUFSIZE)
+ bufsiz = TPM_BUFSIZE;
+
+ count = be32_to_cpu(*((__be32 *) (buf + 2)));
+ ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
+ if (count == 0)
+ return -ENODATA;
+ if (count > bufsiz) {
+ dev_err(chip->pdev,
+ "invalid count value %x %zx\n", count, bufsiz);
+ return -E2BIG;
+ }
+
+ mutex_lock(&chip->tpm_mutex);
+
+ rc = chip->ops->send(chip, (u8 *) buf, count);
+ if (rc < 0) {
+ dev_err(chip->pdev,
+ "tpm_transmit: tpm_send: error %zd\n", rc);
+ goto out;
+ }
+
+ if (chip->vendor.irq)
+ goto out_recv;
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
+ else
+ stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
+ do {
+ u8 status = chip->ops->status(chip);
+ if ((status & chip->ops->req_complete_mask) ==
+ chip->ops->req_complete_val)
+ goto out_recv;
+
+ if (chip->ops->req_canceled(chip, status)) {
+ dev_err(chip->pdev, "Operation Canceled\n");
+ rc = -ECANCELED;
+ goto out;
+ }
+
+ msleep(TPM_TIMEOUT); /* CHECK */
+ rmb();
+ } while (time_before(jiffies, stop));
+
+ chip->ops->cancel(chip);
+ dev_err(chip->pdev, "Operation Timed out\n");
+ rc = -ETIME;
+ goto out;
+
+out_recv:
+ rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
+ if (rc < 0)
+ dev_err(chip->pdev,
+ "tpm_transmit: tpm_recv: error %zd\n", rc);
+out:
+ mutex_unlock(&chip->tpm_mutex);
+ return rc;
+}
+
+#define TPM_DIGEST_SIZE 20
+#define TPM_RET_CODE_IDX 6
+
+ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd,
+ int len, const char *desc)
+{
+ struct tpm_output_header *header;
+ int err;
+
+ len = tpm_transmit(chip, (u8 *) cmd, len);
+ if (len < 0)
+ return len;
+ else if (len < TPM_HEADER_SIZE)
+ return -EFAULT;
+
+ header = cmd;
+
+ err = be32_to_cpu(header->return_code);
+ if (err != 0 && desc)
+ dev_err(chip->pdev, "A TPM error (%d) occurred %s\n", err,
+ desc);
+
+ return err;
+}
+
+#define TPM_INTERNAL_RESULT_SIZE 200
+#define TPM_ORD_GET_CAP cpu_to_be32(101)
+#define TPM_ORD_GET_RANDOM cpu_to_be32(70)
+
+static const struct tpm_input_header tpm_getcap_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(22),
+ .ordinal = TPM_ORD_GET_CAP
+};
+
+ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
+ const char *desc)
+{
+ struct tpm_cmd_t tpm_cmd;
+ int rc;
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+
+ tpm_cmd.header.in = tpm_getcap_header;
+ if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
+ tpm_cmd.params.getcap_in.cap = subcap_id;
+ /*subcap field not necessary */
+ tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
+ tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
+ } else {
+ if (subcap_id == TPM_CAP_FLAG_PERM ||
+ subcap_id == TPM_CAP_FLAG_VOL)
+ tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
+ else
+ tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+ tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+ tpm_cmd.params.getcap_in.subcap = subcap_id;
+ }
+ rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
+ if (!rc)
+ *cap = tpm_cmd.params.getcap_out.cap;
+ return rc;
+}
+
+void tpm_gen_interrupt(struct tpm_chip *chip)
+{
+ struct tpm_cmd_t tpm_cmd;
+ ssize_t rc;
+
+ tpm_cmd.header.in = tpm_getcap_header;
+ tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+ tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+ tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
+
+ rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+ "attempting to determine the timeouts");
+}
+EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
+
+#define TPM_ORD_STARTUP cpu_to_be32(153)
+#define TPM_ST_CLEAR cpu_to_be16(1)
+#define TPM_ST_STATE cpu_to_be16(2)
+#define TPM_ST_DEACTIVATED cpu_to_be16(3)
+static const struct tpm_input_header tpm_startup_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(12),
+ .ordinal = TPM_ORD_STARTUP
+};
+
+static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
+{
+ struct tpm_cmd_t start_cmd;
+ start_cmd.header.in = tpm_startup_header;
+
+ start_cmd.params.startup_in.startup_type = startup_type;
+ return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
+ "attempting to start the TPM");
+}
+
+int tpm_get_timeouts(struct tpm_chip *chip)
+{
+ struct tpm_cmd_t tpm_cmd;
+ unsigned long new_timeout[4];
+ unsigned long old_timeout[4];
+ struct duration_t *duration_cap;
+ ssize_t rc;
+
+ tpm_cmd.header.in = tpm_getcap_header;
+ tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+ tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+ tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
+ rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
+
+ if (rc == TPM_ERR_INVALID_POSTINIT) {
+ /* The TPM is not started, we are the first to talk to it.
+ Execute a startup command. */
+ dev_info(chip->pdev, "Issuing TPM_STARTUP");
+ if (tpm_startup(chip, TPM_ST_CLEAR))
+ return rc;
+
+ tpm_cmd.header.in = tpm_getcap_header;
+ tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+ tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+ tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
+ rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+ NULL);
+ }
+ if (rc) {
+ dev_err(chip->pdev,
+ "A TPM error (%zd) occurred attempting to determine the timeouts\n",
+ rc);
+ goto duration;
+ }
+
+ if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
+ be32_to_cpu(tpm_cmd.header.out.length)
+ != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
+ return -EINVAL;
+
+ old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
+ old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
+ old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
+ old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
+ memcpy(new_timeout, old_timeout, sizeof(new_timeout));
+
+ /*
+ * Provide ability for vendor overrides of timeout values in case
+ * of misreporting.
+ */
+ if (chip->ops->update_timeouts != NULL)
+ chip->vendor.timeout_adjusted =
+ chip->ops->update_timeouts(chip, new_timeout);
+
+ if (!chip->vendor.timeout_adjusted) {
+ /* Don't overwrite default if value is 0 */
+ if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
+ int i;
+
+ /* timeouts in msec rather usec */
+ for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
+ new_timeout[i] *= 1000;
+ chip->vendor.timeout_adjusted = true;
+ }
+ }
+
+ /* Report adjusted timeouts */
+ if (chip->vendor.timeout_adjusted) {
+ dev_info(chip->pdev,
+ HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
+ old_timeout[0], new_timeout[0],
+ old_timeout[1], new_timeout[1],
+ old_timeout[2], new_timeout[2],
+ old_timeout[3], new_timeout[3]);
+ }
+
+ chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]);
+ chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]);
+ chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
+ chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
+
+duration:
+ tpm_cmd.header.in = tpm_getcap_header;
+ tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+ tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+ tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
+
+ rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+ "attempting to determine the durations");
+ if (rc)
+ return rc;
+
+ if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
+ be32_to_cpu(tpm_cmd.header.out.length)
+ != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
+ return -EINVAL;
+
+ duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
+ chip->vendor.duration[TPM_SHORT] =
+ usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
+ chip->vendor.duration[TPM_MEDIUM] =
+ usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
+ chip->vendor.duration[TPM_LONG] =
+ usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
+
+ /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
+ * value wrong and apparently reports msecs rather than usecs. So we
+ * fix up the resulting too-small TPM_SHORT value to make things work.
+ * We also scale the TPM_MEDIUM and -_LONG values by 1000.
+ */
+ if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
+ chip->vendor.duration[TPM_SHORT] = HZ;
+ chip->vendor.duration[TPM_MEDIUM] *= 1000;
+ chip->vendor.duration[TPM_LONG] *= 1000;
+ chip->vendor.duration_adjusted = true;
+ dev_info(chip->pdev, "Adjusting TPM timeout parameters.");
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_get_timeouts);
+
+#define TPM_ORD_CONTINUE_SELFTEST 83
+#define CONTINUE_SELFTEST_RESULT_SIZE 10
+
+static struct tpm_input_header continue_selftest_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(10),
+ .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
+};
+
+/**
+ * tpm_continue_selftest -- run TPM's selftest
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+static int tpm_continue_selftest(struct tpm_chip *chip)
+{
+ int rc;
+ struct tpm_cmd_t cmd;
+
+ cmd.header.in = continue_selftest_header;
+ rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
+ "continue selftest");
+ return rc;
+}
+
+#define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
+#define READ_PCR_RESULT_SIZE 30
+static struct tpm_input_header pcrread_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(14),
+ .ordinal = TPM_ORDINAL_PCRREAD
+};
+
+int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
+{
+ int rc;
+ struct tpm_cmd_t cmd;
+
+ cmd.header.in = pcrread_header;
+ cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
+ rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
+ "attempting to read a pcr value");
+
+ if (rc == 0)
+ memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
+ TPM_DIGEST_SIZE);
+ return rc;
+}
+
+/**
+ * tpm_pcr_read - read a pcr value
+ * @chip_num: tpm idx # or ANY
+ * @pcr_idx: pcr idx to retrieve
+ * @res_buf: TPM_PCR value
+ * size of res_buf is 20 bytes (or NULL if you don't care)
+ *
+ * The TPM driver should be built-in, but for whatever reason it
+ * isn't, protect against the chip disappearing, by incrementing
+ * the module usage count.
+ */
+int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
+{
+ struct tpm_chip *chip;
+ int rc;
+
+ chip = tpm_chip_find_get(chip_num);
+ if (chip == NULL)
+ return -ENODEV;
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
+ else
+ rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
+ tpm_chip_put(chip);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pcr_read);
+
+/**
+ * tpm_pcr_extend - extend pcr value with hash
+ * @chip_num: tpm idx # or AN&
+ * @pcr_idx: pcr idx to extend
+ * @hash: hash value used to extend pcr value
+ *
+ * The TPM driver should be built-in, but for whatever reason it
+ * isn't, protect against the chip disappearing, by incrementing
+ * the module usage count.
+ */
+#define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
+#define EXTEND_PCR_RESULT_SIZE 34
+static struct tpm_input_header pcrextend_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(34),
+ .ordinal = TPM_ORD_PCR_EXTEND
+};
+
+int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
+{
+ struct tpm_cmd_t cmd;
+ int rc;
+ struct tpm_chip *chip;
+
+ chip = tpm_chip_find_get(chip_num);
+ if (chip == NULL)
+ return -ENODEV;
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ rc = tpm2_pcr_extend(chip, pcr_idx, hash);
+ tpm_chip_put(chip);
+ return rc;
+ }
+
+ cmd.header.in = pcrextend_header;
+ cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
+ memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
+ rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+ "attempting extend a PCR value");
+
+ tpm_chip_put(chip);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pcr_extend);
+
+/**
+ * tpm_do_selftest - have the TPM continue its selftest and wait until it
+ * can receive further commands
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+int tpm_do_selftest(struct tpm_chip *chip)
+{
+ int rc;
+ unsigned int loops;
+ unsigned int delay_msec = 100;
+ unsigned long duration;
+ struct tpm_cmd_t cmd;
+
+ duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
+
+ loops = jiffies_to_msecs(duration) / delay_msec;
+
+ rc = tpm_continue_selftest(chip);
+ /* This may fail if there was no TPM driver during a suspend/resume
+ * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
+ */
+ if (rc)
+ return rc;
+
+ do {
+ /* Attempt to read a PCR value */
+ cmd.header.in = pcrread_header;
+ cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
+ rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
+ /* Some buggy TPMs will not respond to tpm_tis_ready() for
+ * around 300ms while the self test is ongoing, keep trying
+ * until the self test duration expires. */
+ if (rc == -ETIME) {
+ dev_info(chip->pdev, HW_ERR "TPM command timed out during continue self test");
+ msleep(delay_msec);
+ continue;
+ }
+
+ if (rc < TPM_HEADER_SIZE)
+ return -EFAULT;
+
+ rc = be32_to_cpu(cmd.header.out.return_code);
+ if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
+ dev_info(chip->pdev,
+ "TPM is disabled/deactivated (0x%X)\n", rc);
+ /* TPM is disabled and/or deactivated; driver can
+ * proceed and TPM does handle commands for
+ * suspend/resume correctly
+ */
+ return 0;
+ }
+ if (rc != TPM_WARN_DOING_SELFTEST)
+ return rc;
+ msleep(delay_msec);
+ } while (--loops > 0);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_do_selftest);
+
+int tpm_send(u32 chip_num, void *cmd, size_t buflen)
+{
+ struct tpm_chip *chip;
+ int rc;
+
+ chip = tpm_chip_find_get(chip_num);
+ if (chip == NULL)
+ return -ENODEV;
+
+ rc = tpm_transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
+
+ tpm_chip_put(chip);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_send);
+
+static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
+ bool check_cancel, bool *canceled)
+{
+ u8 status = chip->ops->status(chip);
+
+ *canceled = false;
+ if ((status & mask) == mask)
+ return true;
+ if (check_cancel && chip->ops->req_canceled(chip, status)) {
+ *canceled = true;
+ return true;
+ }
+ return false;
+}
+
+int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
+ wait_queue_head_t *queue, bool check_cancel)
+{
+ unsigned long stop;
+ long rc;
+ u8 status;
+ bool canceled = false;
+
+ /* check current status */
+ status = chip->ops->status(chip);
+ if ((status & mask) == mask)
+ return 0;
+
+ stop = jiffies + timeout;
+
+ if (chip->vendor.irq) {
+again:
+ timeout = stop - jiffies;
+ if ((long)timeout <= 0)
+ return -ETIME;
+ rc = wait_event_interruptible_timeout(*queue,
+ wait_for_tpm_stat_cond(chip, mask, check_cancel,
+ &canceled),
+ timeout);
+ if (rc > 0) {
+ if (canceled)
+ return -ECANCELED;
+ return 0;
+ }
+ if (rc == -ERESTARTSYS && freezing(current)) {
+ clear_thread_flag(TIF_SIGPENDING);
+ goto again;
+ }
+ } else {
+ do {
+ msleep(TPM_TIMEOUT);
+ status = chip->ops->status(chip);
+ if ((status & mask) == mask)
+ return 0;
+ } while (time_before(jiffies, stop));
+ }
+ return -ETIME;
+}
+EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
+
+#define TPM_ORD_SAVESTATE cpu_to_be32(152)
+#define SAVESTATE_RESULT_SIZE 10
+
+static struct tpm_input_header savestate_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(10),
+ .ordinal = TPM_ORD_SAVESTATE
+};
+
+/*
+ * We are about to suspend. Save the TPM state
+ * so that it can be restored.
+ */
+int tpm_pm_suspend(struct device *dev)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ struct tpm_cmd_t cmd;
+ int rc, try;
+
+ u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
+
+ if (chip == NULL)
+ return -ENODEV;
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ tpm2_shutdown(chip, TPM2_SU_STATE);
+ return 0;
+ }
+
+ /* for buggy tpm, flush pcrs with extend to selected dummy */
+ if (tpm_suspend_pcr) {
+ cmd.header.in = pcrextend_header;
+ cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
+ memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
+ TPM_DIGEST_SIZE);
+ rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+ "extending dummy pcr before suspend");
+ }
+
+ /* now do the actual savestate */
+ for (try = 0; try < TPM_RETRY; try++) {
+ cmd.header.in = savestate_header;
+ rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
+
+ /*
+ * If the TPM indicates that it is too busy to respond to
+ * this command then retry before giving up. It can take
+ * several seconds for this TPM to be ready.
+ *
+ * This can happen if the TPM has already been sent the
+ * SaveState command before the driver has loaded. TCG 1.2
+ * specification states that any communication after SaveState
+ * may cause the TPM to invalidate previously saved state.
+ */
+ if (rc != TPM_WARN_RETRY)
+ break;
+ msleep(TPM_TIMEOUT_RETRY);
+ }
+
+ if (rc)
+ dev_err(chip->pdev,
+ "Error (%d) sending savestate before suspend\n", rc);
+ else if (try > 0)
+ dev_warn(chip->pdev, "TPM savestate took %dms\n",
+ try * TPM_TIMEOUT_RETRY);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pm_suspend);
+
+/*
+ * Resume from a power safe. The BIOS already restored
+ * the TPM state.
+ */
+int tpm_pm_resume(struct device *dev)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+
+ if (chip == NULL)
+ return -ENODEV;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_pm_resume);
+
+#define TPM_GETRANDOM_RESULT_SIZE 18
+static struct tpm_input_header tpm_getrandom_header = {
+ .tag = TPM_TAG_RQU_COMMAND,
+ .length = cpu_to_be32(14),
+ .ordinal = TPM_ORD_GET_RANDOM
+};
+
+/**
+ * tpm_get_random() - Get random bytes from the tpm's RNG
+ * @chip_num: A specific chip number for the request or TPM_ANY_NUM
+ * @out: destination buffer for the random bytes
+ * @max: the max number of bytes to write to @out
+ *
+ * Returns < 0 on error and the number of bytes read on success
+ */
+int tpm_get_random(u32 chip_num, u8 *out, size_t max)
+{
+ struct tpm_chip *chip;
+ struct tpm_cmd_t tpm_cmd;
+ u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
+ int err, total = 0, retries = 5;
+ u8 *dest = out;
+
+ if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
+ return -EINVAL;
+
+ chip = tpm_chip_find_get(chip_num);
+ if (chip == NULL)
+ return -ENODEV;
+
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ err = tpm2_get_random(chip, out, max);
+ tpm_chip_put(chip);
+ return err;
+ }
+
+ do {
+ tpm_cmd.header.in = tpm_getrandom_header;
+ tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
+
+ err = tpm_transmit_cmd(chip, &tpm_cmd,
+ TPM_GETRANDOM_RESULT_SIZE + num_bytes,
+ "attempting get random");
+ if (err)
+ break;
+
+ recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
+ memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
+
+ dest += recd;
+ total += recd;
+ num_bytes -= recd;
+ } while (retries-- && total < max);
+
+ tpm_chip_put(chip);
+ return total ? total : -EIO;
+}
+EXPORT_SYMBOL_GPL(tpm_get_random);
+
+static int __init tpm_init(void)
+{
+ int rc;
+
+ tpm_class = class_create(THIS_MODULE, "tpm");
+ if (IS_ERR(tpm_class)) {
+ pr_err("couldn't create tpm class\n");
+ return PTR_ERR(tpm_class);
+ }
+
+ rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
+ if (rc < 0) {
+ pr_err("tpm: failed to allocate char dev region\n");
+ class_destroy(tpm_class);
+ return rc;
+ }
+
+ return 0;
+}
+
+static void __exit tpm_exit(void)
+{
+ class_destroy(tpm_class);
+ unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
+}
+
+subsys_initcall(tpm_init);
+module_exit(tpm_exit);
+
+MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
+MODULE_DESCRIPTION("TPM Driver");
+MODULE_VERSION("2.0");
+MODULE_LICENSE("GPL");