/* * Copyright (C) 2014, 2015 Intel Corporation * * Authors: * Jarkko Sakkinen * * Maintained by: * * 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 #include 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]; *value = be32_to_cpu(out->value); } 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; }