diff options
Diffstat (limited to 'security/integrity/ima')
-rw-r--r-- | security/integrity/ima/ima_audit.c | 32 | ||||
-rw-r--r-- | security/integrity/ima/ima_crypto.c | 4 | ||||
-rw-r--r-- | security/integrity/ima/ima_fs.c | 8 | ||||
-rw-r--r-- | security/integrity/ima/ima_iint.c | 2 | ||||
-rw-r--r-- | security/integrity/ima/ima_init.c | 4 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 86 | ||||
-rw-r--r-- | security/integrity/ima/ima_policy.c | 48 |
7 files changed, 98 insertions, 86 deletions
diff --git a/security/integrity/ima/ima_audit.c b/security/integrity/ima/ima_audit.c index 1e082bb..ff513ff 100644 --- a/security/integrity/ima/ima_audit.c +++ b/security/integrity/ima/ima_audit.c @@ -22,18 +22,9 @@ static int ima_audit; static int __init ima_audit_setup(char *str) { unsigned long audit; - int rc, result = 0; - char *op = "ima_audit"; - char *cause; - rc = strict_strtoul(str, 0, &audit); - if (rc || audit > 1) - result = 1; - else - ima_audit = audit; - cause = ima_audit ? "enabled" : "not_enabled"; - integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, - op, cause, result, 0); + if (!strict_strtoul(str, 0, &audit)) + ima_audit = audit ? 1 : 0; return 1; } __setup("ima_audit=", ima_audit_setup); @@ -50,23 +41,14 @@ void integrity_audit_msg(int audit_msgno, struct inode *inode, ab = audit_log_start(current->audit_context, GFP_KERNEL, audit_msgno); audit_log_format(ab, "integrity: pid=%d uid=%u auid=%u ses=%u", - current->pid, current->cred->uid, + current->pid, current_cred()->uid, audit_get_loginuid(current), audit_get_sessionid(current)); audit_log_task_context(ab); - switch (audit_msgno) { - case AUDIT_INTEGRITY_DATA: - case AUDIT_INTEGRITY_METADATA: - case AUDIT_INTEGRITY_PCR: - case AUDIT_INTEGRITY_STATUS: - audit_log_format(ab, " op=%s cause=%s", op, cause); - break; - case AUDIT_INTEGRITY_HASH: - audit_log_format(ab, " op=%s hash=%s", op, cause); - break; - default: - audit_log_format(ab, " op=%s", op); - } + audit_log_format(ab, " op="); + audit_log_string(ab, op); + audit_log_format(ab, " cause="); + audit_log_string(ab, cause); audit_log_format(ab, " comm="); audit_log_untrustedstring(ab, current->comm); if (fname) { diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 50d572b..63003a6 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -103,7 +103,7 @@ int ima_calc_template_hash(int template_len, void *template, char *digest) return rc; } -static void ima_pcrread(int idx, u8 *pcr) +static void __init ima_pcrread(int idx, u8 *pcr) { if (!ima_used_chip) return; @@ -115,7 +115,7 @@ static void ima_pcrread(int idx, u8 *pcr) /* * Calculate the boot aggregate hash */ -int ima_calc_boot_aggregate(char *digest) +int __init ima_calc_boot_aggregate(char *digest) { struct hash_desc desc; struct scatterlist sg; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 510186f..6bfc7ea 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -15,6 +15,7 @@ * implemenents security file system for reporting * current measurement list and IMA statistics */ +#include <linux/fcntl.h> #include <linux/module.h> #include <linux/seq_file.h> #include <linux/rculist.h> @@ -283,6 +284,9 @@ static atomic_t policy_opencount = ATOMIC_INIT(1); */ int ima_open_policy(struct inode * inode, struct file * filp) { + /* No point in being allowed to open it if you aren't going to write */ + if (!(filp->f_flags & O_WRONLY)) + return -EACCES; if (atomic_dec_and_test(&policy_opencount)) return 0; return -EBUSY; @@ -315,7 +319,7 @@ static struct file_operations ima_measure_policy_ops = { .release = ima_release_policy }; -int ima_fs_init(void) +int __init ima_fs_init(void) { ima_dir = securityfs_create_dir("ima", NULL); if (IS_ERR(ima_dir)) @@ -349,7 +353,7 @@ int ima_fs_init(void) goto out; ima_policy = securityfs_create_file("policy", - S_IRUSR | S_IRGRP | S_IWUSR, + S_IWUSR, ima_dir, NULL, &ima_measure_policy_ops); if (IS_ERR(ima_policy)) diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c index ec79f1e..b8dd693 100644 --- a/security/integrity/ima/ima_iint.c +++ b/security/integrity/ima/ima_iint.c @@ -196,7 +196,7 @@ static void init_once(void *foo) kref_set(&iint->refcount, 1); } -void ima_iintcache_init(void) +void __init ima_iintcache_init(void) { iint_cache = kmem_cache_create("iint_cache", sizeof(struct ima_iint_cache), 0, diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 0b0bb8c..a40da7a 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -38,7 +38,7 @@ int ima_used_chip; * a different value.) Violations add a zero entry to the measurement * list and extend the aggregate PCR value with ff...ff's. */ -static void ima_add_boot_aggregate(void) +static void __init ima_add_boot_aggregate(void) { struct ima_template_entry *entry; const char *op = "add_boot_aggregate"; @@ -71,7 +71,7 @@ err_out: audit_cause, result, 0); } -int ima_init(void) +int __init ima_init(void) { u8 pcr_i[IMA_DIGEST_SIZE]; int rc; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index f4e7266..6f61187 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -29,20 +29,8 @@ int ima_initialized; char *ima_hash = "sha1"; static int __init hash_setup(char *str) { - const char *op = "hash_setup"; - const char *hash = "sha1"; - int result = 0; - int audit_info = 0; - - if (strncmp(str, "md5", 3) == 0) { - hash = "md5"; - ima_hash = str; - } else if (strncmp(str, "sha1", 4) != 0) { - hash = "invalid_hash_type"; - result = 1; - } - integrity_audit_msg(AUDIT_INTEGRITY_HASH, NULL, NULL, op, hash, - result, audit_info); + if (strncmp(str, "md5", 3) == 0) + ima_hash = "md5"; return 1; } __setup("ima_hash=", hash_setup); @@ -128,10 +116,6 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, { int rc = 0; - if (IS_ERR(file)) { - pr_info("%s dentry_open failed\n", filename); - return rc; - } iint->opencount++; iint->readcount++; @@ -141,6 +125,15 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, return rc; } +static void ima_update_counts(struct ima_iint_cache *iint, int mask) +{ + iint->opencount++; + if ((mask & MAY_WRITE) || (mask == 0)) + iint->writecount++; + else if (mask & (MAY_READ | MAY_EXEC)) + iint->readcount++; +} + /** * ima_path_check - based on policy, collect/store measurement. * @path: contains a pointer to the path to be measured @@ -156,10 +149,10 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file, * - Opening a file for read when already open for write, * could result in a file measurement error. * - * Return 0 on success, an error code on failure. - * (Based on the results of appraise_measurement().) + * Always return 0 and audit dentry_open failures. + * (Return code will be based upon measurement appraisal.) */ -int ima_path_check(struct path *path, int mask) +int ima_path_check(struct path *path, int mask, int update_counts) { struct inode *inode = path->dentry->d_inode; struct ima_iint_cache *iint; @@ -173,11 +166,8 @@ int ima_path_check(struct path *path, int mask) return 0; mutex_lock(&iint->mutex); - iint->opencount++; - if ((mask & MAY_WRITE) || (mask == 0)) - iint->writecount++; - else if (mask & (MAY_READ | MAY_EXEC)) - iint->readcount++; + if (update_counts) + ima_update_counts(iint, mask); rc = ima_must_measure(iint, inode, MAY_READ, PATH_CHECK); if (rc < 0) @@ -196,7 +186,19 @@ int ima_path_check(struct path *path, int mask) struct dentry *dentry = dget(path->dentry); struct vfsmount *mnt = mntget(path->mnt); - file = dentry_open(dentry, mnt, O_RDONLY, current->cred); + file = dentry_open(dentry, mnt, O_RDONLY | O_LARGEFILE, + current_cred()); + if (IS_ERR(file)) { + int audit_info = 0; + + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, + dentry->d_name.name, + "add_measurement", + "dentry_open failed", + 1, audit_info); + file = NULL; + goto out; + } rc = get_path_measurement(iint, file, dentry->d_name.name); } out: @@ -206,6 +208,7 @@ out: kref_put(&iint->refcount, iint_free); return 0; } +EXPORT_SYMBOL_GPL(ima_path_check); static int process_measurement(struct file *file, const unsigned char *filename, int mask, int function) @@ -234,7 +237,16 @@ out: return rc; } -static void opencount_get(struct file *file) +/* + * ima_opens_get - increment file counts + * + * - for IPC shm and shmat file. + * - for nfsd exported files. + * + * Increment the counts for these files to prevent unnecessary + * imbalance messages. + */ +void ima_counts_get(struct file *file) { struct inode *inode = file->f_dentry->d_inode; struct ima_iint_cache *iint; @@ -246,8 +258,14 @@ static void opencount_get(struct file *file) return; mutex_lock(&iint->mutex); iint->opencount++; + if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) + iint->readcount++; + + if (file->f_mode & FMODE_WRITE) + iint->writecount++; mutex_unlock(&iint->mutex); } +EXPORT_SYMBOL_GPL(ima_counts_get); /** * ima_file_mmap - based on policy, collect/store measurement. @@ -272,18 +290,6 @@ int ima_file_mmap(struct file *file, unsigned long prot) return 0; } -/* - * ima_shm_check - IPC shm and shmat create/fput a file - * - * Maintain the opencount for these files to prevent unnecessary - * imbalance messages. - */ -void ima_shm_check(struct file *file) -{ - opencount_get(file); - return; -} - /** * ima_bprm_check - based on policy, collect/store measurement. * @bprm: contains the linux_binprm structure diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index b5291ad..e127839 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -45,24 +45,30 @@ struct ima_measure_rule_entry { } lsm[MAX_LSM_RULES]; }; -/* Without LSM specific knowledge, the default policy can only be +/* + * Without LSM specific knowledge, the default policy can only be * written in terms of .action, .func, .mask, .fsmagic, and .uid */ + +/* + * The minimum rule set to allow for full TCB coverage. Measures all files + * opened or mmap for exec and everything read by root. Dangerous because + * normal users can easily run the machine out of memory simply building + * and running executables. + */ static struct ima_measure_rule_entry default_rules[] = { - {.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC, - .flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC}, - {.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC, - .flags = IMA_FSMAGIC}, - {.action = DONT_MEASURE,.fsmagic = 0xF97CFF8C,.flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC}, {.action = MEASURE,.func = FILE_MMAP,.mask = MAY_EXEC, .flags = IMA_FUNC | IMA_MASK}, {.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC, .flags = IMA_FUNC | IMA_MASK}, {.action = MEASURE,.func = PATH_CHECK,.mask = MAY_READ,.uid = 0, - .flags = IMA_FUNC | IMA_MASK | IMA_UID} + .flags = IMA_FUNC | IMA_MASK | IMA_UID}, }; static LIST_HEAD(measure_default_rules); @@ -71,6 +77,14 @@ static struct list_head *ima_measure; static DEFINE_MUTEX(ima_measure_mutex); +static bool ima_use_tcb __initdata; +static int __init default_policy_setup(char *str) +{ + ima_use_tcb = 1; + return 1; +} +__setup("ima_tcb", default_policy_setup); + /** * ima_match_rules - determine whether an inode matches the measure rule. * @rule: a pointer to a rule @@ -96,7 +110,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, if ((rule->flags & IMA_UID) && rule->uid != tsk->cred->uid) return false; for (i = 0; i < MAX_LSM_RULES; i++) { - int rc; + int rc = 0; u32 osid, sid; if (!rule->lsm[i].rule) @@ -109,7 +123,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, security_inode_getsecid(inode, &osid); rc = security_filter_rule_match(osid, rule->lsm[i].type, - AUDIT_EQUAL, + Audit_equal, rule->lsm[i].rule, NULL); break; @@ -119,7 +133,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, security_task_getsecid(tsk, &sid); rc = security_filter_rule_match(sid, rule->lsm[i].type, - AUDIT_EQUAL, + Audit_equal, rule->lsm[i].rule, NULL); default: @@ -164,11 +178,17 @@ int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask) * ima_measure points to either the measure_default_rules or the * the new measure_policy_rules. */ -void ima_init_policy(void) +void __init ima_init_policy(void) { - int i; + int i, entries; + + /* if !ima_use_tcb set entries = 0 so we load NO default rules */ + if (ima_use_tcb) + entries = ARRAY_SIZE(default_rules); + else + entries = 0; - for (i = 0; i < ARRAY_SIZE(default_rules); i++) + for (i = 0; i < entries; i++) list_add_tail(&default_rules[i].list, &measure_default_rules); ima_measure = &measure_default_rules; } @@ -227,7 +247,7 @@ static int ima_lsm_rule_init(struct ima_measure_rule_entry *entry, entry->lsm[lsm_rule].type = audit_type; result = security_filter_rule_init(entry->lsm[lsm_rule].type, - AUDIT_EQUAL, args, + Audit_equal, args, &entry->lsm[lsm_rule].rule); return result; } |