// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2004 IBM 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>
 *
 * Copyright (C) 2013 Obsidian Research Corp
 * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
 *
 * sysfs filesystem inspection interface to the TPM
 */
#include <linux/device.h>
#include "tpm.h"

struct tpm_readpubek_out {
        u8 algorithm[4];
        u8 encscheme[2];
        u8 sigscheme[2];
        __be32 paramsize;
        u8 parameters[12];
        __be32 keysize;
        u8 modulus[256];
        u8 checksum[20];
} __packed;

#define READ_PUBEK_RESULT_MIN_BODY_SIZE (28 + 256)
#define TPM_ORD_READPUBEK 124

static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
                          char *buf)
{
        struct tpm_buf tpm_buf;
        struct tpm_readpubek_out *out;
        int i;
        char *str = buf;
        struct tpm_chip *chip = to_tpm_chip(dev);
        char anti_replay[20];

        memset(&anti_replay, 0, sizeof(anti_replay));

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm_buf_init(&tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK))
                goto out_ops;

        tpm_buf_append(&tpm_buf, anti_replay, sizeof(anti_replay));

        if (tpm_transmit_cmd(chip, &tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
                             "attempting to read the PUBEK"))
                goto out_buf;

        out = (struct tpm_readpubek_out *)&tpm_buf.data[10];
        str +=
            sprintf(str,
                    "Algorithm: %4ph\n"
                    "Encscheme: %2ph\n"
                    "Sigscheme: %2ph\n"
                    "Parameters: %12ph\n"
                    "Modulus length: %d\n"
                    "Modulus:\n",
                    out->algorithm,
                    out->encscheme,
                    out->sigscheme,
                    out->parameters,
                    be32_to_cpu(out->keysize));

        for (i = 0; i < 256; i += 16)
                str += sprintf(str, "%16ph\n", &out->modulus[i]);

out_buf:
        tpm_buf_destroy(&tpm_buf);
out_ops:
        tpm_put_ops(chip);
        return str - buf;
}
static DEVICE_ATTR_RO(pubek);

static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        cap_t cap;
        u8 digest[TPM_DIGEST_SIZE];
        u32 i, j, num_pcrs;
        char *str = buf;
        struct tpm_chip *chip = to_tpm_chip(dev);

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm1_getcap(chip, TPM_CAP_PROP_PCR, &cap,
                        "attempting to determine the number of PCRS",
                        sizeof(cap.num_pcrs))) {
                tpm_put_ops(chip);
                return 0;
        }

        num_pcrs = be32_to_cpu(cap.num_pcrs);
        for (i = 0; i < num_pcrs; i++) {
                if (tpm1_pcr_read(chip, i, digest)) {
                        str = buf;
                        break;
                }
                str += sprintf(str, "PCR-%02d: ", i);
                for (j = 0; j < TPM_DIGEST_SIZE; j++)
                        str += sprintf(str, "%02X ", digest[j]);
                str += sprintf(str, "\n");
        }
        tpm_put_ops(chip);
        return str - buf;
}
static DEVICE_ATTR_RO(pcrs);

static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
                     char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);
        ssize_t rc = 0;
        cap_t cap;

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
                        "attempting to determine the permanent enabled state",
                        sizeof(cap.perm_flags)))
                goto out_ops;

        rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
out_ops:
        tpm_put_ops(chip);
        return rc;
}
static DEVICE_ATTR_RO(enabled);

static ssize_t active_show(struct device *dev, struct device_attribute *attr,
                    char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);
        ssize_t rc = 0;
        cap_t cap;

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm1_getcap(chip, TPM_CAP_FLAG_PERM, &cap,
                        "attempting to determine the permanent active state",
                        sizeof(cap.perm_flags)))
                goto out_ops;

        rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
out_ops:
        tpm_put_ops(chip);
        return rc;
}
static DEVICE_ATTR_RO(active);

static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
                          char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);
        ssize_t rc = 0;
        cap_t cap;

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_PROP_OWNER, &cap,
                        "attempting to determine the owner state",
                        sizeof(cap.owned)))
                goto out_ops;

        rc = sprintf(buf, "%d\n", cap.owned);
out_ops:
        tpm_put_ops(chip);
        return rc;
}
static DEVICE_ATTR_RO(owned);

static ssize_t temp_deactivated_show(struct device *dev,
                                     struct device_attribute *attr, char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);
        ssize_t rc = 0;
        cap_t cap;

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm1_getcap(to_tpm_chip(dev), TPM_CAP_FLAG_VOL, &cap,
                        "attempting to determine the temporary state",
                        sizeof(cap.stclear_flags)))
                goto out_ops;

        rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
out_ops:
        tpm_put_ops(chip);
        return rc;
}
static DEVICE_ATTR_RO(temp_deactivated);

static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);
        struct tpm1_version *version;
        ssize_t rc = 0;
        char *str = buf;
        cap_t cap;

        if (tpm_try_get_ops(chip))
                return 0;

        if (tpm1_getcap(chip, TPM_CAP_PROP_MANUFACTURER, &cap,
                        "attempting to determine the manufacturer",
                        sizeof(cap.manufacturer_id)))
                goto out_ops;

        str += sprintf(str, "Manufacturer: 0x%x\n",
                       be32_to_cpu(cap.manufacturer_id));

        /* TPM 1.2 */
        if (!tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
                         "attempting to determine the 1.2 version",
                         sizeof(cap.version2))) {
                version = &cap.version2.version;
                goto out_print;
        }

        /* TPM 1.1 */
        if (tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
                        "attempting to determine the 1.1 version",
                        sizeof(cap.version1))) {
                goto out_ops;
        }

        version = &cap.version1;

out_print:
        str += sprintf(str,
                       "TCG version: %d.%d\nFirmware version: %d.%d\n",
                       version->major, version->minor,
                       version->rev_major, version->rev_minor);

        rc = str - buf;

out_ops:
        tpm_put_ops(chip);
        return rc;
}
static DEVICE_ATTR_RO(caps);

static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
                            const char *buf, size_t count)
{
        struct tpm_chip *chip = to_tpm_chip(dev);

        if (tpm_try_get_ops(chip))
                return 0;

        chip->ops->cancel(chip);
        tpm_put_ops(chip);
        return count;
}
static DEVICE_ATTR_WO(cancel);

static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
                              char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);

        if (chip->duration[TPM_LONG] == 0)
                return 0;

        return sprintf(buf, "%d %d %d [%s]\n",
                       jiffies_to_usecs(chip->duration[TPM_SHORT]),
                       jiffies_to_usecs(chip->duration[TPM_MEDIUM]),
                       jiffies_to_usecs(chip->duration[TPM_LONG]),
                       chip->duration_adjusted
                       ? "adjusted" : "original");
}
static DEVICE_ATTR_RO(durations);

static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
                             char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);

        return sprintf(buf, "%d %d %d %d [%s]\n",
                       jiffies_to_usecs(chip->timeout_a),
                       jiffies_to_usecs(chip->timeout_b),
                       jiffies_to_usecs(chip->timeout_c),
                       jiffies_to_usecs(chip->timeout_d),
                       chip->timeout_adjusted
                       ? "adjusted" : "original");
}
static DEVICE_ATTR_RO(timeouts);

static ssize_t tpm_version_major_show(struct device *dev,
                                  struct device_attribute *attr, char *buf)
{
        struct tpm_chip *chip = to_tpm_chip(dev);

        return sprintf(buf, "%s\n", chip->flags & TPM_CHIP_FLAG_TPM2
                       ? "2" : "1");
}
static DEVICE_ATTR_RO(tpm_version_major);

static struct attribute *tpm1_dev_attrs[] = {
        &dev_attr_pubek.attr,
        &dev_attr_pcrs.attr,
        &dev_attr_enabled.attr,
        &dev_attr_active.attr,
        &dev_attr_owned.attr,
        &dev_attr_temp_deactivated.attr,
        &dev_attr_caps.attr,
        &dev_attr_cancel.attr,
        &dev_attr_durations.attr,
        &dev_attr_timeouts.attr,
        &dev_attr_tpm_version_major.attr,
        NULL,
};

static struct attribute *tpm2_dev_attrs[] = {
        &dev_attr_tpm_version_major.attr,
        NULL
};

static const struct attribute_group tpm1_dev_group = {
        .attrs = tpm1_dev_attrs,
};

static const struct attribute_group tpm2_dev_group = {
        .attrs = tpm2_dev_attrs,
};

struct tpm_pcr_attr {
        int alg_id;
        int pcr;
        struct device_attribute attr;
};

#define to_tpm_pcr_attr(a) container_of(a, struct tpm_pcr_attr, attr)

static ssize_t pcr_value_show(struct device *dev,
                              struct device_attribute *attr,
                              char *buf)
{
        struct tpm_pcr_attr *ha = to_tpm_pcr_attr(attr);
        struct tpm_chip *chip = to_tpm_chip(dev);
        struct tpm_digest digest;
        int i;
        int digest_size = 0;
        int rc;
        char *str = buf;

        for (i = 0; i < chip->nr_allocated_banks; i++)
                if (ha->alg_id == chip->allocated_banks[i].alg_id)
                        digest_size = chip->allocated_banks[i].digest_size;
        /* should never happen */
        if (!digest_size)
                return -EINVAL;

        digest.alg_id = ha->alg_id;
        rc = tpm_pcr_read(chip, ha->pcr, &digest);
        if (rc)
                return rc;
        for (i = 0; i < digest_size; i++)
                str += sprintf(str, "%02X", digest.digest[i]);
        str += sprintf(str, "\n");

        return str - buf;
}

/*
 * The following set of defines represents all the magic to build
 * the per hash attribute groups for displaying each bank of PCRs.
 * The only slight problem with this approach is that every PCR is
 * hard coded to be present, so you don't know if an PCR is missing
 * until a cat of the file returns -EINVAL
 *
 * Also note you must ignore checkpatch warnings in this macro
 * code. This is deep macro magic that checkpatch.pl doesn't
 * understand.
 */

/* Note, this must match TPM2_PLATFORM_PCR which is fixed at 24. */
#define _TPM_HELPER(_alg, _hash, F) \
        F(_alg, _hash, 0)           \
        F(_alg, _hash, 1)           \
        F(_alg, _hash, 2)           \
        F(_alg, _hash, 3)           \
        F(_alg, _hash, 4)           \
        F(_alg, _hash, 5)           \
        F(_alg, _hash, 6)           \
        F(_alg, _hash, 7)           \
        F(_alg, _hash, 8)           \
        F(_alg, _hash, 9)           \
        F(_alg, _hash, 10)          \
        F(_alg, _hash, 11)          \
        F(_alg, _hash, 12)          \
        F(_alg, _hash, 13)          \
        F(_alg, _hash, 14)          \
        F(_alg, _hash, 15)          \
        F(_alg, _hash, 16)          \
        F(_alg, _hash, 17)          \
        F(_alg, _hash, 18)          \
        F(_alg, _hash, 19)          \
        F(_alg, _hash, 20)          \
        F(_alg, _hash, 21)          \
        F(_alg, _hash, 22)          \
        F(_alg, _hash, 23)

/* ignore checkpatch warning about trailing ; in macro. */
#define PCR_ATTR(_alg, _hash, _pcr)                                \
        static struct tpm_pcr_attr dev_attr_pcr_##_hash##_##_pcr = {    \
                .alg_id = _alg,                                    \
                .pcr = _pcr,                                       \
                .attr = {                                          \
                        .attr = {                                  \
                                .name = __stringify(_pcr),         \
                                .mode = 0444                       \
                        },                                         \
                        .show = pcr_value_show                     \
                }                                                  \
        };

#define PCR_ATTRS(_alg, _hash)                  \
        _TPM_HELPER(_alg, _hash, PCR_ATTR)

/* ignore checkpatch warning about trailing , in macro. */
#define PCR_ATTR_VAL(_alg, _hash, _pcr)         \
        &dev_attr_pcr_##_hash##_##_pcr.attr.attr,

#define PCR_ATTR_GROUP_ARRAY(_alg, _hash)                      \
        static struct attribute *pcr_group_attrs_##_hash[] = { \
                _TPM_HELPER(_alg, _hash, PCR_ATTR_VAL)         \
                NULL                                           \
        }

#define PCR_ATTR_GROUP(_alg, _hash)                         \
        static struct attribute_group pcr_group_##_hash = { \
                .name = "pcr-" __stringify(_hash),          \
                .attrs = pcr_group_attrs_##_hash            \
        }

#define PCR_ATTR_BUILD(_alg, _hash)        \
        PCR_ATTRS(_alg, _hash)             \
        PCR_ATTR_GROUP_ARRAY(_alg, _hash); \
        PCR_ATTR_GROUP(_alg, _hash)
/*
 * End of macro structure to build an attribute group containing 24
 * PCR value files for each supported hash algorithm
 */

/*
 * The next set of macros implements the cleverness for each hash to
 * build a static attribute group called pcr_group_<hash> which can be
 * added to chip->groups[].
 *
 * The first argument is the TPM algorithm id and the second is the
 * hash used as both the suffix and the group name.  Note: the group
 * name is a directory in the top level tpm class with the name
 * pcr-<hash>, so it must not clash with any other names already
 * in the sysfs directory.
 */
PCR_ATTR_BUILD(TPM_ALG_SHA1, sha1);
PCR_ATTR_BUILD(TPM_ALG_SHA256, sha256);
PCR_ATTR_BUILD(TPM_ALG_SHA384, sha384);
PCR_ATTR_BUILD(TPM_ALG_SHA512, sha512);
PCR_ATTR_BUILD(TPM_ALG_SM3_256, sm3);


void tpm_sysfs_add_device(struct tpm_chip *chip)
{
        int i;

        WARN_ON(chip->groups_cnt != 0);

        if (chip->flags & TPM_CHIP_FLAG_TPM2)
                chip->groups[chip->groups_cnt++] = &tpm2_dev_group;
        else
                chip->groups[chip->groups_cnt++] = &tpm1_dev_group;

        /* add one group for each bank hash */
        for (i = 0; i < chip->nr_allocated_banks; i++) {
                switch (chip->allocated_banks[i].alg_id) {
                case TPM_ALG_SHA1:
                        chip->groups[chip->groups_cnt++] = &pcr_group_sha1;
                        break;
                case TPM_ALG_SHA256:
                        chip->groups[chip->groups_cnt++] = &pcr_group_sha256;
                        break;
                case TPM_ALG_SHA384:
                        chip->groups[chip->groups_cnt++] = &pcr_group_sha384;
                        break;
                case TPM_ALG_SHA512:
                        chip->groups[chip->groups_cnt++] = &pcr_group_sha512;
                        break;
                case TPM_ALG_SM3_256:
                        chip->groups[chip->groups_cnt++] = &pcr_group_sm3;
                        break;
                default:
                        /*
                         * If triggers, send a patch to add both a
                         * PCR_ATTR_BUILD() macro above for the
                         * missing algorithm as well as an additional
                         * case in this switch statement.
                         */
                        dev_err(&chip->dev,
                                "TPM with unsupported bank algorithm 0x%04x",
                                chip->allocated_banks[i].alg_id);
                        break;
                }
        }

        /*
         * This will only trigger if someone has added an additional
         * hash to the tpm_algorithms enum without incrementing
         * TPM_MAX_HASHES.
         */
        WARN_ON(chip->groups_cnt > TPM_MAX_HASHES + 1);
}