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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/security/integrity/ima/ima_api.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/security/integrity/ima/ima_api.c')
-rw-r--r-- | kernel/security/integrity/ima/ima_api.c | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/kernel/security/integrity/ima/ima_api.c b/kernel/security/integrity/ima/ima_api.c new file mode 100644 index 000000000..b8a27c505 --- /dev/null +++ b/kernel/security/integrity/ima/ima_api.c @@ -0,0 +1,337 @@ +/* + * Copyright (C) 2008 IBM Corporation + * + * Author: 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_api.c + * Implements must_appraise_or_measure, collect_measurement, + * appraise_measurement, store_measurement and store_template. + */ +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/xattr.h> +#include <linux/evm.h> +#include <crypto/hash_info.h> +#include "ima.h" + +/* + * ima_free_template_entry - free an existing template entry + */ +void ima_free_template_entry(struct ima_template_entry *entry) +{ + int i; + + for (i = 0; i < entry->template_desc->num_fields; i++) + kfree(entry->template_data[i].data); + + kfree(entry); +} + +/* + * ima_alloc_init_template - create and initialize a new template entry + */ +int ima_alloc_init_template(struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, struct ima_template_entry **entry) +{ + struct ima_template_desc *template_desc = ima_template_desc_current(); + int i, result = 0; + + *entry = kzalloc(sizeof(**entry) + template_desc->num_fields * + sizeof(struct ima_field_data), GFP_NOFS); + if (!*entry) + return -ENOMEM; + + (*entry)->template_desc = template_desc; + for (i = 0; i < template_desc->num_fields; i++) { + struct ima_template_field *field = template_desc->fields[i]; + u32 len; + + result = field->field_init(iint, file, filename, + xattr_value, xattr_len, + &((*entry)->template_data[i])); + if (result != 0) + goto out; + + len = (*entry)->template_data[i].len; + (*entry)->template_data_len += sizeof(len); + (*entry)->template_data_len += len; + } + return 0; +out: + ima_free_template_entry(*entry); + *entry = NULL; + return result; +} + +/* + * ima_store_template - store ima template measurements + * + * Calculate the hash of a template entry, add the template entry + * to an ordered list of measurement entries maintained inside the kernel, + * and also update the aggregate integrity value (maintained inside the + * configured TPM PCR) over the hashes of the current list of measurement + * entries. + * + * Applications retrieve the current kernel-held measurement list through + * the securityfs entries in /sys/kernel/security/ima. The signed aggregate + * TPM PCR (called quote) can be retrieved using a TPM user space library + * and is used to validate the measurement list. + * + * Returns 0 on success, error code otherwise + */ +int ima_store_template(struct ima_template_entry *entry, + int violation, struct inode *inode, + const unsigned char *filename) +{ + static const char op[] = "add_template_measure"; + static const char audit_cause[] = "hashing_error"; + char *template_name = entry->template_desc->name; + int result; + struct { + struct ima_digest_data hdr; + char digest[TPM_DIGEST_SIZE]; + } hash; + + if (!violation) { + int num_fields = entry->template_desc->num_fields; + + /* this function uses default algo */ + hash.hdr.algo = HASH_ALGO_SHA1; + result = ima_calc_field_array_hash(&entry->template_data[0], + entry->template_desc, + num_fields, &hash.hdr); + if (result < 0) { + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, + template_name, op, + audit_cause, result, 0); + return result; + } + memcpy(entry->digest, hash.hdr.digest, hash.hdr.length); + } + result = ima_add_template_entry(entry, violation, op, inode, filename); + return result; +} + +/* + * ima_add_violation - add violation to measurement list. + * + * Violations are flagged in the measurement list with zero hash values. + * By extending the PCR with 0xFF's instead of with zeroes, the PCR + * value is invalidated. + */ +void ima_add_violation(struct file *file, const unsigned char *filename, + const char *op, const char *cause) +{ + struct ima_template_entry *entry; + struct inode *inode = file_inode(file); + int violation = 1; + int result; + + /* can overflow, only indicator */ + atomic_long_inc(&ima_htable.violations); + + result = ima_alloc_init_template(NULL, file, filename, + NULL, 0, &entry); + if (result < 0) { + result = -ENOMEM; + goto err_out; + } + result = ima_store_template(entry, violation, inode, filename); + if (result < 0) + ima_free_template_entry(entry); +err_out: + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename, + op, cause, result, 0); +} + +/** + * ima_get_action - appraise & measure decision based on policy. + * @inode: pointer to inode to measure + * @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXECUTE) + * @function: calling function (FILE_CHECK, BPRM_CHECK, MMAP_CHECK, MODULE_CHECK) + * + * The policy is defined in terms of keypairs: + * subj=, obj=, type=, func=, mask=, fsmagic= + * subj,obj, and type: are LSM specific. + * func: FILE_CHECK | BPRM_CHECK | MMAP_CHECK | MODULE_CHECK + * mask: contains the permission mask + * fsmagic: hex value + * + * Returns IMA_MEASURE, IMA_APPRAISE mask. + * + */ +int ima_get_action(struct inode *inode, int mask, int function) +{ + int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE; + + flags &= ima_policy_flag; + + return ima_match_policy(inode, function, mask, flags); +} + +/* + * ima_collect_measurement - collect file measurement + * + * Calculate the file hash, if it doesn't already exist, + * storing the measurement and i_version in the iint. + * + * Must be called with iint->mutex held. + * + * Return 0 on success, error code otherwise + */ +int ima_collect_measurement(struct integrity_iint_cache *iint, + struct file *file, + struct evm_ima_xattr_data **xattr_value, + int *xattr_len) +{ + const char *audit_cause = "failed"; + struct inode *inode = file_inode(file); + const char *filename = file->f_path.dentry->d_name.name; + int result = 0; + struct { + struct ima_digest_data hdr; + char digest[IMA_MAX_DIGEST_SIZE]; + } hash; + + if (xattr_value) + *xattr_len = ima_read_xattr(file->f_path.dentry, xattr_value); + + if (!(iint->flags & IMA_COLLECTED)) { + u64 i_version = file_inode(file)->i_version; + + if (file->f_flags & O_DIRECT) { + audit_cause = "failed(directio)"; + result = -EACCES; + goto out; + } + + /* use default hash algorithm */ + hash.hdr.algo = ima_hash_algo; + + if (xattr_value) + ima_get_hash_algo(*xattr_value, *xattr_len, &hash.hdr); + + result = ima_calc_file_hash(file, &hash.hdr); + if (!result) { + int length = sizeof(hash.hdr) + hash.hdr.length; + void *tmpbuf = krealloc(iint->ima_hash, length, + GFP_NOFS); + if (tmpbuf) { + iint->ima_hash = tmpbuf; + memcpy(iint->ima_hash, &hash, length); + iint->version = i_version; + iint->flags |= IMA_COLLECTED; + } else + result = -ENOMEM; + } + } +out: + if (result) + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, + filename, "collect_data", audit_cause, + result, 0); + return result; +} + +/* + * ima_store_measurement - store file measurement + * + * Create an "ima" template and then store the template by calling + * ima_store_template. + * + * We only get here if the inode has not already been measured, + * but the measurement could already exist: + * - multiple copies of the same file on either the same or + * different filesystems. + * - the inode was previously flushed as well as the iint info, + * containing the hashing info. + * + * Must be called with iint->mutex held. + */ +void ima_store_measurement(struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len) +{ + static const char op[] = "add_template_measure"; + static const char audit_cause[] = "ENOMEM"; + int result = -ENOMEM; + struct inode *inode = file_inode(file); + struct ima_template_entry *entry; + int violation = 0; + + if (iint->flags & IMA_MEASURED) + return; + + result = ima_alloc_init_template(iint, file, filename, + xattr_value, xattr_len, &entry); + if (result < 0) { + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename, + op, audit_cause, result, 0); + return; + } + + result = ima_store_template(entry, violation, inode, filename); + if (!result || result == -EEXIST) + iint->flags |= IMA_MEASURED; + if (result < 0) + ima_free_template_entry(entry); +} + +void ima_audit_measurement(struct integrity_iint_cache *iint, + const unsigned char *filename) +{ + struct audit_buffer *ab; + char hash[(iint->ima_hash->length * 2) + 1]; + const char *algo_name = hash_algo_name[iint->ima_hash->algo]; + char algo_hash[sizeof(hash) + strlen(algo_name) + 2]; + int i; + + if (iint->flags & IMA_AUDITED) + return; + + for (i = 0; i < iint->ima_hash->length; i++) + hex_byte_pack(hash + (i * 2), iint->ima_hash->digest[i]); + hash[i * 2] = '\0'; + + ab = audit_log_start(current->audit_context, GFP_KERNEL, + AUDIT_INTEGRITY_RULE); + if (!ab) + return; + + audit_log_format(ab, "file="); + audit_log_untrustedstring(ab, filename); + audit_log_format(ab, " hash="); + snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash); + audit_log_untrustedstring(ab, algo_hash); + + audit_log_task_info(ab, current); + audit_log_end(ab); + + iint->flags |= IMA_AUDITED; +} + +const char *ima_d_path(struct path *path, char **pathbuf) +{ + char *pathname = NULL; + + *pathbuf = __getname(); + if (*pathbuf) { + pathname = d_absolute_path(path, *pathbuf, PATH_MAX); + if (IS_ERR(pathname)) { + __putname(*pathbuf); + *pathbuf = NULL; + pathname = NULL; + } + } + return pathname ?: (const char *)path->dentry->d_name.name; +} |