/* * Copyright (C) 2005,2006,2007,2008 IBM Corporation * * Authors: * Reiner Sailer <sailer@watson.ibm.com> * Leendert van Doorn <leendert@watson.ibm.com> * Mimi Zohar <zohar@us.ibm.com> * * 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. * * File: ima_init.c * initialization and cleanup functions */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h> #include <linux/scatterlist.h> #include <linux/slab.h> #include <linux/err.h> #include "ima.h" /* name for boot aggregate entry */ static const char boot_aggregate_name[] = "boot_aggregate"; struct tpm_chip *ima_tpm_chip; /* Add the boot aggregate to the IMA measurement list and extend * the PCR register. * * Calculate the boot aggregate, a SHA1 over tpm registers 0-7, * assuming a TPM chip exists, and zeroes if the TPM chip does not * exist. Add the boot aggregate measurement to the measurement * list and extend the PCR register. * * If a tpm chip does not exist, indicate the core root of trust is * not hardware based by invalidating the aggregate PCR value. * (The aggregate PCR value is invalidated by adding one value to * the measurement list and extending the aggregate PCR value with * a different value.) Violations add a zero entry to the measurement * list and extend the aggregate PCR value with ff...ff's. */ static int __init ima_add_boot_aggregate(void) { static const char op[] = "add_boot_aggregate"; const char *audit_cause = "ENOMEM"; struct ima_template_entry *entry; struct integrity_iint_cache tmp_iint, *iint = &tmp_iint; struct ima_event_data event_data = {iint, NULL, boot_aggregate_name, NULL, 0, NULL}; int result = -ENOMEM; int violation = 0; struct { struct ima_digest_data hdr; char digest[TPM_DIGEST_SIZE]; } hash; memset(iint, 0, sizeof(*iint)); memset(&hash, 0, sizeof(hash)); iint->ima_hash = &hash.hdr; iint->ima_hash->algo = HASH_ALGO_SHA1; iint->ima_hash->length = SHA1_DIGEST_SIZE; if (ima_tpm_chip) { result = ima_calc_boot_aggregate(&hash.hdr); if (result < 0) { audit_cause = "hashing_error"; goto err_out; } } result = ima_alloc_init_template(&event_data, &entry); if (result < 0) { audit_cause = "alloc_entry"; goto err_out; } result = ima_store_template(entry, violation, NULL, boot_aggregate_name, CONFIG_IMA_MEASURE_PCR_IDX); if (result < 0) { ima_free_template_entry(entry); audit_cause = "store_entry"; goto err_out; } return 0; err_out: integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL, boot_aggregate_name, op, audit_cause, result, 0); return result; } #ifdef CONFIG_IMA_LOAD_X509 void __init ima_load_x509(void) { int unset_flags = ima_policy_flag & IMA_APPRAISE; ima_policy_flag &= ~unset_flags; integrity_load_x509(INTEGRITY_KEYRING_IMA, CONFIG_IMA_X509_PATH); ima_policy_flag |= unset_flags; } #endif int __init ima_init(void) { int rc; ima_tpm_chip = tpm_default_chip(); if (!ima_tpm_chip) pr_info("No TPM chip found, activating TPM-bypass!\n"); rc = integrity_init_keyring(INTEGRITY_KEYRING_IMA); if (rc) return rc; rc = ima_init_crypto(); if (rc) return rc; rc = ima_init_template(); if (rc != 0) return rc; /* It can be called before ima_init_digests(), it does not use TPM. */ ima_load_kexec_buffer(); rc = ima_init_digests(); if (rc != 0) return rc; rc = ima_add_boot_aggregate(); /* boot aggregate must be first entry */ if (rc != 0) return rc; ima_init_policy(); return ima_fs_init(); }