diff options
Diffstat (limited to 'drivers/char/tpm/tpm2-cmd.c')
| -rw-r--r-- | drivers/char/tpm/tpm2-cmd.c | 1049 |
1 files changed, 1049 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c new file mode 100644 index 000000000..ce497b069 --- /dev/null +++ b/drivers/char/tpm/tpm2-cmd.c @@ -0,0 +1,1049 @@ +/* + * Copyright (C) 2014, 2015 Intel Corporation + * + * Authors: + * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> + * + * Maintained by: <tpmdd-devel@lists.sourceforge.net> + * + * This file contains TPM2 protocol implementations of the commands + * used by the kernel internally. + * + * 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. + */ + +#include "tpm.h" +#include <crypto/hash_info.h> +#include <keys/trusted-type.h> + +enum tpm2_object_attributes { + TPM2_OA_USER_WITH_AUTH = BIT(6), +}; + +enum tpm2_session_attributes { + TPM2_SA_CONTINUE_SESSION = BIT(0), +}; + +struct tpm2_hash { + unsigned int crypto_id; + unsigned int tpm_id; +}; + +static struct tpm2_hash tpm2_hash_map[] = { + {HASH_ALGO_SHA1, TPM2_ALG_SHA1}, + {HASH_ALGO_SHA256, TPM2_ALG_SHA256}, + {HASH_ALGO_SHA384, TPM2_ALG_SHA384}, + {HASH_ALGO_SHA512, TPM2_ALG_SHA512}, + {HASH_ALGO_SM3_256, TPM2_ALG_SM3_256}, +}; + +/* + * Array with one entry per ordinal defining the maximum amount + * of time the chip could take to return the result. The values + * of the SHORT, MEDIUM, and LONG durations are taken from the + * PC Client Profile (PTP) specification. + * LONG_LONG is for commands that generates keys which empirically + * takes longer time on some systems. + */ +static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = { + TPM_UNDEFINED, /* 11F */ + TPM_UNDEFINED, /* 120 */ + TPM_LONG, /* 121 */ + TPM_UNDEFINED, /* 122 */ + TPM_UNDEFINED, /* 123 */ + TPM_UNDEFINED, /* 124 */ + TPM_UNDEFINED, /* 125 */ + TPM_UNDEFINED, /* 126 */ + TPM_UNDEFINED, /* 127 */ + TPM_UNDEFINED, /* 128 */ + TPM_LONG, /* 129 */ + TPM_UNDEFINED, /* 12a */ + TPM_UNDEFINED, /* 12b */ + TPM_UNDEFINED, /* 12c */ + TPM_UNDEFINED, /* 12d */ + TPM_UNDEFINED, /* 12e */ + TPM_UNDEFINED, /* 12f */ + TPM_UNDEFINED, /* 130 */ + TPM_LONG_LONG, /* 131 */ + TPM_UNDEFINED, /* 132 */ + TPM_UNDEFINED, /* 133 */ + TPM_UNDEFINED, /* 134 */ + TPM_UNDEFINED, /* 135 */ + TPM_UNDEFINED, /* 136 */ + TPM_UNDEFINED, /* 137 */ + TPM_UNDEFINED, /* 138 */ + TPM_UNDEFINED, /* 139 */ + TPM_UNDEFINED, /* 13a */ + TPM_UNDEFINED, /* 13b */ + TPM_UNDEFINED, /* 13c */ + TPM_UNDEFINED, /* 13d */ + TPM_MEDIUM, /* 13e */ + TPM_UNDEFINED, /* 13f */ + TPM_UNDEFINED, /* 140 */ + TPM_UNDEFINED, /* 141 */ + TPM_UNDEFINED, /* 142 */ + TPM_LONG, /* 143 */ + TPM_MEDIUM, /* 144 */ + TPM_UNDEFINED, /* 145 */ + TPM_UNDEFINED, /* 146 */ + TPM_UNDEFINED, /* 147 */ + TPM_UNDEFINED, /* 148 */ + TPM_UNDEFINED, /* 149 */ + TPM_UNDEFINED, /* 14a */ + TPM_UNDEFINED, /* 14b */ + TPM_UNDEFINED, /* 14c */ + TPM_UNDEFINED, /* 14d */ + TPM_LONG, /* 14e */ + TPM_UNDEFINED, /* 14f */ + TPM_UNDEFINED, /* 150 */ + TPM_UNDEFINED, /* 151 */ + TPM_UNDEFINED, /* 152 */ + TPM_LONG_LONG, /* 153 */ + TPM_UNDEFINED, /* 154 */ + TPM_UNDEFINED, /* 155 */ + TPM_UNDEFINED, /* 156 */ + TPM_UNDEFINED, /* 157 */ + TPM_UNDEFINED, /* 158 */ + TPM_UNDEFINED, /* 159 */ + TPM_UNDEFINED, /* 15a */ + TPM_UNDEFINED, /* 15b */ + TPM_MEDIUM, /* 15c */ + TPM_UNDEFINED, /* 15d */ + TPM_UNDEFINED, /* 15e */ + TPM_UNDEFINED, /* 15f */ + TPM_UNDEFINED, /* 160 */ + TPM_UNDEFINED, /* 161 */ + TPM_UNDEFINED, /* 162 */ + TPM_UNDEFINED, /* 163 */ + TPM_UNDEFINED, /* 164 */ + TPM_UNDEFINED, /* 165 */ + TPM_UNDEFINED, /* 166 */ + TPM_UNDEFINED, /* 167 */ + TPM_UNDEFINED, /* 168 */ + TPM_UNDEFINED, /* 169 */ + TPM_UNDEFINED, /* 16a */ + TPM_UNDEFINED, /* 16b */ + TPM_UNDEFINED, /* 16c */ + TPM_UNDEFINED, /* 16d */ + TPM_UNDEFINED, /* 16e */ + TPM_UNDEFINED, /* 16f */ + TPM_UNDEFINED, /* 170 */ + TPM_UNDEFINED, /* 171 */ + TPM_UNDEFINED, /* 172 */ + TPM_UNDEFINED, /* 173 */ + TPM_UNDEFINED, /* 174 */ + TPM_UNDEFINED, /* 175 */ + TPM_UNDEFINED, /* 176 */ + TPM_LONG, /* 177 */ + TPM_UNDEFINED, /* 178 */ + TPM_UNDEFINED, /* 179 */ + TPM_MEDIUM, /* 17a */ + TPM_LONG, /* 17b */ + TPM_UNDEFINED, /* 17c */ + TPM_UNDEFINED, /* 17d */ + TPM_UNDEFINED, /* 17e */ + TPM_UNDEFINED, /* 17f */ + TPM_UNDEFINED, /* 180 */ + TPM_UNDEFINED, /* 181 */ + TPM_MEDIUM, /* 182 */ + TPM_UNDEFINED, /* 183 */ + TPM_UNDEFINED, /* 184 */ + TPM_MEDIUM, /* 185 */ + TPM_MEDIUM, /* 186 */ + TPM_UNDEFINED, /* 187 */ + TPM_UNDEFINED, /* 188 */ + TPM_UNDEFINED, /* 189 */ + TPM_UNDEFINED, /* 18a */ + TPM_UNDEFINED, /* 18b */ + TPM_UNDEFINED, /* 18c */ + TPM_UNDEFINED, /* 18d */ + TPM_UNDEFINED, /* 18e */ + TPM_UNDEFINED /* 18f */ +}; + +struct tpm2_pcr_read_out { + __be32 update_cnt; + __be32 pcr_selects_cnt; + __be16 hash_alg; + u8 pcr_select_size; + u8 pcr_select[TPM2_PCR_SELECT_MIN]; + __be32 digests_cnt; + __be16 digest_size; + u8 digest[]; +} __packed; + +/** + * tpm2_pcr_read() - read a PCR value + * @chip: TPM chip to use. + * @pcr_idx: index of the PCR to read. + * @res_buf: buffer to store the resulting hash. + * + * Return: Same as with tpm_transmit_cmd. + */ +int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) +{ + int rc; + struct tpm_buf buf; + struct tpm2_pcr_read_out *out; + u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0}; + + if (pcr_idx >= TPM2_PLATFORM_PCR) + return -EINVAL; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ); + if (rc) + return rc; + + pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7); + + tpm_buf_append_u32(&buf, 1); + tpm_buf_append_u16(&buf, TPM2_ALG_SHA1); + tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN); + tpm_buf_append(&buf, (const unsigned char *)pcr_select, + sizeof(pcr_select)); + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, + res_buf ? "attempting to read a pcr value" : NULL); + if (rc == 0 && res_buf) { + out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE]; + memcpy(res_buf, out->digest, SHA1_DIGEST_SIZE); + } + + tpm_buf_destroy(&buf); + return rc; +} + +struct tpm2_null_auth_area { + __be32 handle; + __be16 nonce_size; + u8 attributes; + __be16 auth_size; +} __packed; + +/** + * tpm2_pcr_extend() - extend a PCR value + * + * @chip: TPM chip to use. + * @pcr_idx: index of the PCR. + * @count: number of digests passed. + * @digests: list of pcr banks and corresponding digest values to extend. + * + * Return: Same as with tpm_transmit_cmd. + */ +int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count, + struct tpm2_digest *digests) +{ + struct tpm_buf buf; + struct tpm2_null_auth_area auth_area; + int rc; + int i; + int j; + + if (count > ARRAY_SIZE(chip->active_banks)) + return -EINVAL; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, pcr_idx); + + auth_area.handle = cpu_to_be32(TPM2_RS_PW); + auth_area.nonce_size = 0; + auth_area.attributes = 0; + auth_area.auth_size = 0; + + tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area)); + tpm_buf_append(&buf, (const unsigned char *)&auth_area, + sizeof(auth_area)); + tpm_buf_append_u32(&buf, count); + + for (i = 0; i < count; i++) { + for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) { + if (digests[i].alg_id != tpm2_hash_map[j].tpm_id) + continue; + tpm_buf_append_u16(&buf, digests[i].alg_id); + tpm_buf_append(&buf, (const unsigned char + *)&digests[i].digest, + hash_digest_size[tpm2_hash_map[j].crypto_id]); + } + } + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, + "attempting extend a PCR value"); + + tpm_buf_destroy(&buf); + + return rc; +} + + +struct tpm2_get_random_out { + __be16 size; + u8 buffer[TPM_MAX_RNG_DATA]; +} __packed; + +/** + * tpm2_get_random() - get random bytes from the TPM RNG + * + * @chip: a &tpm_chip instance + * @dest: destination buffer + * @max: the max number of random bytes to pull + * + * Return: + * size of the buffer on success, + * -errno otherwise + */ +int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max) +{ + struct tpm2_get_random_out *out; + struct tpm_buf buf; + u32 recd; + u32 num_bytes = max; + int err; + int total = 0; + int retries = 5; + u8 *dest_ptr = dest; + + if (!num_bytes || max > TPM_MAX_RNG_DATA) + return -EINVAL; + + err = tpm_buf_init(&buf, 0, 0); + if (err) + return err; + + do { + tpm_buf_reset(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_RANDOM); + tpm_buf_append_u16(&buf, num_bytes); + err = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, + offsetof(struct tpm2_get_random_out, + buffer), + 0, "attempting get random"); + if (err) + goto out; + + out = (struct tpm2_get_random_out *) + &buf.data[TPM_HEADER_SIZE]; + recd = min_t(u32, be16_to_cpu(out->size), num_bytes); + if (tpm_buf_length(&buf) < + TPM_HEADER_SIZE + + offsetof(struct tpm2_get_random_out, buffer) + + recd) { + err = -EFAULT; + goto out; + } + memcpy(dest_ptr, out->buffer, recd); + + dest_ptr += recd; + total += recd; + num_bytes -= recd; + } while (retries-- && total < max); + + tpm_buf_destroy(&buf); + return total ? total : -EIO; +out: + tpm_buf_destroy(&buf); + return err; +} + +/** + * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * + * Return: same as with tpm_transmit_cmd + */ +void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle, + unsigned int flags) +{ + struct tpm_buf buf; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT); + if (rc) { + dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n", + handle); + return; + } + + tpm_buf_append_u32(&buf, handle); + + (void) tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, flags, + "flushing context"); + + tpm_buf_destroy(&buf); +} + +/** + * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer. + * + * @buf: an allocated tpm_buf instance + * @session_handle: session handle + * @nonce: the session nonce, may be NULL if not used + * @nonce_len: the session nonce length, may be 0 if not used + * @attributes: the session attributes + * @hmac: the session HMAC or password, may be NULL if not used + * @hmac_len: the session HMAC or password length, maybe 0 if not used + */ +static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle, + const u8 *nonce, u16 nonce_len, + u8 attributes, + const u8 *hmac, u16 hmac_len) +{ + tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len); + tpm_buf_append_u32(buf, session_handle); + tpm_buf_append_u16(buf, nonce_len); + + if (nonce && nonce_len) + tpm_buf_append(buf, nonce, nonce_len); + + tpm_buf_append_u8(buf, attributes); + tpm_buf_append_u16(buf, hmac_len); + + if (hmac && hmac_len) + tpm_buf_append(buf, hmac, hmac_len); +} + +/** + * tpm2_seal_trusted() - seal the payload of a trusted key + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * + * Return: < 0 on error and 0 on success. + */ +int tpm2_seal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options) +{ + unsigned int blob_len; + struct tpm_buf buf; + u32 hash; + int i; + int rc; + + for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) { + if (options->hash == tpm2_hash_map[i].crypto_id) { + hash = tpm2_hash_map[i].tpm_id; + break; + } + } + + if (i == ARRAY_SIZE(tpm2_hash_map)) + return -EINVAL; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, options->keyhandle); + tpm2_buf_append_auth(&buf, TPM2_RS_PW, + NULL /* nonce */, 0, + 0 /* session_attributes */, + options->keyauth /* hmac */, + TPM_DIGEST_SIZE); + + /* sensitive */ + tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1); + + tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE); + tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE); + tpm_buf_append_u16(&buf, payload->key_len + 1); + tpm_buf_append(&buf, payload->key, payload->key_len); + tpm_buf_append_u8(&buf, payload->migratable); + + /* public */ + tpm_buf_append_u16(&buf, 14 + options->policydigest_len); + tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH); + tpm_buf_append_u16(&buf, hash); + + /* policy */ + if (options->policydigest_len) { + tpm_buf_append_u32(&buf, 0); + tpm_buf_append_u16(&buf, options->policydigest_len); + tpm_buf_append(&buf, options->policydigest, + options->policydigest_len); + } else { + tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH); + tpm_buf_append_u16(&buf, 0); + } + + /* public parameters */ + tpm_buf_append_u16(&buf, TPM2_ALG_NULL); + tpm_buf_append_u16(&buf, 0); + + /* outside info */ + tpm_buf_append_u16(&buf, 0); + + /* creation PCR */ + tpm_buf_append_u32(&buf, 0); + + if (buf.flags & TPM_BUF_OVERFLOW) { + rc = -E2BIG; + goto out; + } + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, 0, + "sealing data"); + if (rc) + goto out; + + blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]); + if (blob_len > MAX_BLOB_SIZE) { + rc = -E2BIG; + goto out; + } + if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) { + rc = -EFAULT; + goto out; + } + + memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len); + payload->blob_len = blob_len; + +out: + tpm_buf_destroy(&buf); + + if (rc > 0) { + if (tpm2_rc_value(rc) == TPM2_RC_HASH) + rc = -EINVAL; + else + rc = -EPERM; + } + + return rc; +} + +/** + * tpm2_load_cmd() - execute a TPM2_Load command + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * @blob_handle: returned blob handle + * @flags: tpm transmit flags + * + * Return: 0 on success. + * -E2BIG on wrong payload size. + * -EPERM on tpm error status. + * < 0 error from tpm_transmit_cmd. + */ +static int tpm2_load_cmd(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options, + u32 *blob_handle, unsigned int flags) +{ + struct tpm_buf buf; + unsigned int private_len; + unsigned int public_len; + unsigned int blob_len; + int rc; + + private_len = be16_to_cpup((__be16 *) &payload->blob[0]); + if (private_len > (payload->blob_len - 2)) + return -E2BIG; + + public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]); + blob_len = private_len + public_len + 4; + if (blob_len > payload->blob_len) + return -E2BIG; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, options->keyhandle); + tpm2_buf_append_auth(&buf, TPM2_RS_PW, + NULL /* nonce */, 0, + 0 /* session_attributes */, + options->keyauth /* hmac */, + TPM_DIGEST_SIZE); + + tpm_buf_append(&buf, payload->blob, blob_len); + + if (buf.flags & TPM_BUF_OVERFLOW) { + rc = -E2BIG; + goto out; + } + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 4, flags, + "loading blob"); + if (!rc) + *blob_handle = be32_to_cpup( + (__be32 *) &buf.data[TPM_HEADER_SIZE]); + +out: + tpm_buf_destroy(&buf); + + if (rc > 0) + rc = -EPERM; + + return rc; +} + +/** + * tpm2_unseal_cmd() - execute a TPM2_Unload command + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * @blob_handle: blob handle + * @flags: tpm_transmit_cmd flags + * + * Return: 0 on success + * -EPERM on tpm error status + * < 0 error from tpm_transmit_cmd + */ +static int tpm2_unseal_cmd(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options, + u32 blob_handle, unsigned int flags) +{ + struct tpm_buf buf; + u16 data_len; + u8 *data; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, blob_handle); + tpm2_buf_append_auth(&buf, + options->policyhandle ? + options->policyhandle : TPM2_RS_PW, + NULL /* nonce */, 0, + TPM2_SA_CONTINUE_SESSION, + options->blobauth /* hmac */, + TPM_DIGEST_SIZE); + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 6, flags, + "unsealing"); + if (rc > 0) + rc = -EPERM; + + if (!rc) { + data_len = be16_to_cpup( + (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]); + if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) { + rc = -EFAULT; + goto out; + } + + if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) { + rc = -EFAULT; + goto out; + } + data = &buf.data[TPM_HEADER_SIZE + 6]; + + memcpy(payload->key, data, data_len - 1); + payload->key_len = data_len - 1; + payload->migratable = data[data_len - 1]; + } + +out: + tpm_buf_destroy(&buf); + return rc; +} + +/** + * tpm2_unseal_trusted() - unseal the payload of a trusted key + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * + * Return: Same as with tpm_transmit_cmd. + */ +int tpm2_unseal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options) +{ + u32 blob_handle; + int rc; + + mutex_lock(&chip->tpm_mutex); + rc = tpm2_load_cmd(chip, payload, options, &blob_handle, + TPM_TRANSMIT_UNLOCKED); + if (rc) + goto out; + + rc = tpm2_unseal_cmd(chip, payload, options, blob_handle, + TPM_TRANSMIT_UNLOCKED); + tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED); +out: + mutex_unlock(&chip->tpm_mutex); + return rc; +} + +struct tpm2_get_cap_out { + u8 more_data; + __be32 subcap_id; + __be32 property_cnt; + __be32 property_id; + __be32 value; +} __packed; + +/** + * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property + * @chip: a &tpm_chip instance + * @property_id: property ID. + * @value: output variable. + * @desc: passed to tpm_transmit_cmd() + * + * Return: + * 0 on success, + * -errno or a TPM return code otherwise + */ +ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value, + const char *desc) +{ + struct tpm2_get_cap_out *out; + struct tpm_buf buf; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); + if (rc) + return rc; + tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES); + tpm_buf_append_u32(&buf, property_id); + tpm_buf_append_u32(&buf, 1); + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL); + if (!rc) { + out = (struct tpm2_get_cap_out *) + &buf.data[TPM_HEADER_SIZE]; + /* + * To prevent failing boot up of some systems, Infineon TPM2.0 + * returns SUCCESS on TPM2_Startup in field upgrade mode. Also + * the TPM2_Getcapability command returns a zero length list + * in field upgrade mode. + */ + if (be32_to_cpu(out->property_cnt) > 0) + *value = be32_to_cpu(out->value); + else + rc = -ENODATA; + } + tpm_buf_destroy(&buf); + return rc; +} +EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt); + +/** + * tpm2_shutdown() - send a TPM shutdown command + * + * Sends a TPM shutdown command. The shutdown command is used in call + * sites where the system is going down. If it fails, there is not much + * that can be done except print an error message. + * + * @chip: a &tpm_chip instance + * @shutdown_type: TPM_SU_CLEAR or TPM_SU_STATE. + */ +void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type) +{ + struct tpm_buf buf; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN); + if (rc) + return; + tpm_buf_append_u16(&buf, shutdown_type); + tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, + "stopping the TPM"); + tpm_buf_destroy(&buf); +} + +/* + * tpm2_calc_ordinal_duration() - maximum duration for a command + * + * @chip: TPM chip to use. + * @ordinal: command code number. + * + * Return: maximum duration for a command + */ +unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal) +{ + int index = TPM_UNDEFINED; + int duration = 0; + + if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST) + index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST]; + + if (index != TPM_UNDEFINED) + duration = chip->duration[index]; + + if (duration <= 0) + duration = msecs_to_jiffies(TPM2_DURATION_DEFAULT); + + return duration; +} +EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration); + +/** + * tpm2_do_selftest() - ensure that all self tests have passed + * + * @chip: TPM chip to use + * + * Return: Same as with tpm_transmit_cmd. + * + * The TPM can either run all self tests synchronously and then return + * RC_SUCCESS once all tests were successful. Or it can choose to run the tests + * asynchronously and return RC_TESTING immediately while the self tests still + * execute in the background. This function handles both cases and waits until + * all tests have completed. + */ +static int tpm2_do_selftest(struct tpm_chip *chip) +{ + struct tpm_buf buf; + int full; + int rc; + + for (full = 0; full < 2; full++) { + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST); + if (rc) + return rc; + + tpm_buf_append_u8(&buf, full); + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, + "attempting the self test"); + tpm_buf_destroy(&buf); + + if (rc == TPM2_RC_TESTING) + rc = TPM2_RC_SUCCESS; + if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS) + return rc; + } + + return rc; +} + +/** + * tpm2_probe() - probe for the TPM 2.0 protocol + * @chip: a &tpm_chip instance + * + * Send an idempotent TPM 2.0 command and see whether there is TPM2 chip in the + * other end based on the response tag. The flag TPM_CHIP_FLAG_TPM2 is set by + * this function if this is the case. + * + * Return: + * 0 on success, + * -errno otherwise + */ +int tpm2_probe(struct tpm_chip *chip) +{ + struct tpm_output_header *out; + struct tpm_buf buf; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); + if (rc) + return rc; + tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES); + tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS); + tpm_buf_append_u32(&buf, 1); + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL); + /* We ignore TPM return codes on purpose. */ + if (rc >= 0) { + out = (struct tpm_output_header *)buf.data; + if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS) + chip->flags |= TPM_CHIP_FLAG_TPM2; + } + tpm_buf_destroy(&buf); + return 0; +} +EXPORT_SYMBOL_GPL(tpm2_probe); + +struct tpm2_pcr_selection { + __be16 hash_alg; + u8 size_of_select; + u8 pcr_select[3]; +} __packed; + +static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) +{ + struct tpm2_pcr_selection pcr_selection; + struct tpm_buf buf; + void *marker; + void *end; + void *pcr_select_offset; + unsigned int count; + u32 sizeof_pcr_selection; + u32 rsp_len; + int rc; + int i = 0; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, TPM2_CAP_PCRS); + tpm_buf_append_u32(&buf, 0); + tpm_buf_append_u32(&buf, 1); + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 9, 0, + "get tpm pcr allocation"); + if (rc) + goto out; + + count = be32_to_cpup( + (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); + + if (count > ARRAY_SIZE(chip->active_banks)) { + rc = -ENODEV; + goto out; + } + + marker = &buf.data[TPM_HEADER_SIZE + 9]; + + rsp_len = be32_to_cpup((__be32 *)&buf.data[2]); + end = &buf.data[rsp_len]; + + for (i = 0; i < count; i++) { + pcr_select_offset = marker + + offsetof(struct tpm2_pcr_selection, size_of_select); + if (pcr_select_offset >= end) { + rc = -EFAULT; + break; + } + + memcpy(&pcr_selection, marker, sizeof(pcr_selection)); + chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg); + sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) + + sizeof(pcr_selection.size_of_select) + + pcr_selection.size_of_select; + marker = marker + sizeof_pcr_selection; + } + +out: + if (i < ARRAY_SIZE(chip->active_banks)) + chip->active_banks[i] = TPM2_ALG_ERROR; + + tpm_buf_destroy(&buf); + + return rc; +} + +static int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip) +{ + struct tpm_buf buf; + u32 nr_commands; + __be32 *attrs; + u32 cc; + int i; + int rc; + + rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL); + if (rc) + goto out; + + if (nr_commands > 0xFFFFF) { + rc = -EFAULT; + goto out; + } + + chip->cc_attrs_tbl = devm_kcalloc(&chip->dev, 4, nr_commands, + GFP_KERNEL); + if (!chip->cc_attrs_tbl) { + rc = -ENOMEM; + goto out; + } + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); + if (rc) + goto out; + + tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS); + tpm_buf_append_u32(&buf, TPM2_CC_FIRST); + tpm_buf_append_u32(&buf, nr_commands); + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, + 9 + 4 * nr_commands, 0, NULL); + if (rc) { + tpm_buf_destroy(&buf); + goto out; + } + + if (nr_commands != + be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) { + rc = -EFAULT; + tpm_buf_destroy(&buf); + goto out; + } + + chip->nr_commands = nr_commands; + + attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9]; + for (i = 0; i < nr_commands; i++, attrs++) { + chip->cc_attrs_tbl[i] = be32_to_cpup(attrs); + cc = chip->cc_attrs_tbl[i] & 0xFFFF; + + if (cc == TPM2_CC_CONTEXT_SAVE || cc == TPM2_CC_FLUSH_CONTEXT) { + chip->cc_attrs_tbl[i] &= + ~(GENMASK(2, 0) << TPM2_CC_ATTR_CHANDLES); + chip->cc_attrs_tbl[i] |= 1 << TPM2_CC_ATTR_CHANDLES; + } + } + + tpm_buf_destroy(&buf); + +out: + if (rc > 0) + rc = -ENODEV; + return rc; +} + +/** + * tpm2_auto_startup - Perform the standard automatic TPM initialization + * sequence + * @chip: TPM chip to use + * + * Returns 0 on success, < 0 in case of fatal error. + */ +int tpm2_auto_startup(struct tpm_chip *chip) +{ + int rc; + + rc = tpm_get_timeouts(chip); + if (rc) + goto out; + + rc = tpm2_do_selftest(chip); + if (rc && rc != TPM2_RC_INITIALIZE) + goto out; + + if (rc == TPM2_RC_INITIALIZE) { + rc = tpm_startup(chip); + if (rc) + goto out; + + rc = tpm2_do_selftest(chip); + if (rc) + goto out; + } + + rc = tpm2_get_pcr_allocation(chip); + if (rc) + goto out; + + rc = tpm2_get_cc_attrs_tbl(chip); + +out: + if (rc > 0) + rc = -ENODEV; + return rc; +} + +int tpm2_find_cc(struct tpm_chip *chip, u32 cc) +{ + int i; + + for (i = 0; i < chip->nr_commands; i++) + if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0))) + return i; + + return -1; +} |