diff options
Diffstat (limited to 'security')
34 files changed, 1727 insertions, 447 deletions
diff --git a/security/Kconfig b/security/Kconfig index bb244774e9d..d23c839038f 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -110,28 +110,8 @@ config SECURITY_ROOTPLUG See <http://www.linuxjournal.com/article.php?sid=6279> for more information about this module. - - If you are unsure how to answer this question, answer N. - -config SECURITY_DEFAULT_MMAP_MIN_ADDR - int "Low address space to protect from user allocation" - depends on SECURITY - default 0 - help - This is the portion of low virtual memory which should be protected - from userspace allocation. Keeping a user from writing to low pages - can help reduce the impact of kernel NULL pointer bugs. - - For most ia64, ppc64 and x86 users with lots of address space - a value of 65536 is reasonable and should cause no problems. - On arm and other archs it should not be higher than 32768. - Programs which use vm86 functionality would either need additional - permissions from either the LSM or the capabilities module or have - this protection disabled. - - This value can be changed after boot using the - /proc/sys/vm/mmap_min_addr tunable. + If you are unsure how to answer this question, answer N. source security/selinux/Kconfig source security/smack/Kconfig diff --git a/security/Makefile b/security/Makefile index fa77021d977..c67557cdaa8 100644 --- a/security/Makefile +++ b/security/Makefile @@ -16,6 +16,9 @@ obj-$(CONFIG_SECURITYFS) += inode.o # Must precede capability.o in order to stack properly. obj-$(CONFIG_SECURITY_SELINUX) += selinux/built-in.o obj-$(CONFIG_SECURITY_SMACK) += smack/built-in.o +ifeq ($(CONFIG_AUDIT),y) +obj-$(CONFIG_SECURITY_SMACK) += lsm_audit.o +endif obj-$(CONFIG_SECURITY_TOMOYO) += tomoyo/built-in.o obj-$(CONFIG_SECURITY_ROOTPLUG) += root_plug.o obj-$(CONFIG_CGROUP_DEVICE) += device_cgroup.o diff --git a/security/commoncap.c b/security/commoncap.c index beac0258c2a..48b7e0228fa 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -28,6 +28,28 @@ #include <linux/prctl.h> #include <linux/securebits.h> +/* + * If a non-root user executes a setuid-root binary in + * !secure(SECURE_NOROOT) mode, then we raise capabilities. + * However if fE is also set, then the intent is for only + * the file capabilities to be applied, and the setuid-root + * bit is left on either to change the uid (plausible) or + * to get full privilege on a kernel without file capabilities + * support. So in that case we do not raise capabilities. + * + * Warn if that happens, once per boot. + */ +static void warn_setuid_and_fcaps_mixed(char *fname) +{ + static int warned; + if (!warned) { + printk(KERN_INFO "warning: `%s' has both setuid-root and" + " effective capabilities. Therefore not raising all" + " capabilities.\n", fname); + warned = 1; + } +} + int cap_netlink_send(struct sock *sk, struct sk_buff *skb) { NETLINK_CB(skb).eff_cap = current_cap(); @@ -464,6 +486,15 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (!issecure(SECURE_NOROOT)) { /* + * If the legacy file capability is set, then don't set privs + * for a setuid root binary run by a non-root user. Do set it + * for a root user just to cause least surprise to an admin. + */ + if (effective && new->uid != 0 && new->euid == 0) { + warn_setuid_and_fcaps_mixed(bprm->filename); + goto skip; + } + /* * To support inheritance of root-permissions and suid-root * executables under compatibility mode, we override the * capability sets for the file. @@ -478,6 +509,7 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) if (new->euid == 0) effective = true; } +skip: /* Don't let someone trace a set[ug]id/setpcap binary with the revised * credentials unless they have the appropriate permit diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 5fda7df1972..b8186bac8b7 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -490,7 +490,7 @@ int devcgroup_inode_permission(struct inode *inode, int mask) list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) { if (wh->type & DEV_ALL) - goto acc_check; + goto found; if ((wh->type & DEV_BLOCK) && !S_ISBLK(inode->i_mode)) continue; if ((wh->type & DEV_CHAR) && !S_ISCHR(inode->i_mode)) @@ -499,11 +499,12 @@ int devcgroup_inode_permission(struct inode *inode, int mask) continue; if (wh->minor != ~0 && wh->minor != iminor(inode)) continue; -acc_check: + if ((mask & MAY_WRITE) && !(wh->access & ACC_WRITE)) continue; if ((mask & MAY_READ) && !(wh->access & ACC_READ)) continue; +found: rcu_read_unlock(); return 0; } @@ -527,7 +528,7 @@ int devcgroup_inode_mknod(int mode, dev_t dev) list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) { if (wh->type & DEV_ALL) - goto acc_check; + goto found; if ((wh->type & DEV_BLOCK) && !S_ISBLK(mode)) continue; if ((wh->type & DEV_CHAR) && !S_ISCHR(mode)) @@ -536,9 +537,10 @@ int devcgroup_inode_mknod(int mode, dev_t dev) continue; if (wh->minor != ~0 && wh->minor != MINOR(dev)) continue; -acc_check: + if (!(wh->access & ACC_MKNOD)) continue; +found: rcu_read_unlock(); return 0; } diff --git a/security/inode.c b/security/inode.c index f3b91bfbe4c..f7496c6a022 100644 --- a/security/inode.c +++ b/security/inode.c @@ -287,7 +287,7 @@ void securityfs_remove(struct dentry *dentry) { struct dentry *parent; - if (!dentry) + if (!dentry || IS_ERR(dentry)) return; parent = dentry->d_parent; diff --git a/security/integrity/ima/ima_audit.c b/security/integrity/ima/ima_audit.c index 1e082bb987b..ff513ff737f 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 50d572b74ca..63003a63aae 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 510186f0b72..6bfc7eaebfd 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 ec79f1ee992..b8dd693f879 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 0b0bb8c978c..a40da7ae590 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 f4e7266f5ae..101c512564e 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 +237,43 @@ out: return rc; } -static void opencount_get(struct file *file) +/* + * ima_counts_put - decrement file counts + * + * File counts are incremented in ima_path_check. On file open + * error, such as ETXTBSY, decrement the counts to prevent + * unnecessary imbalance messages. + */ +void ima_counts_put(struct path *path, int mask) +{ + struct inode *inode = path->dentry->d_inode; + struct ima_iint_cache *iint; + + if (!ima_initialized || !S_ISREG(inode->i_mode)) + return; + iint = ima_iint_find_insert_get(inode); + if (!iint) + return; + + mutex_lock(&iint->mutex); + iint->opencount--; + if ((mask & MAY_WRITE) || (mask == 0)) + iint->writecount--; + else if (mask & (MAY_READ | MAY_EXEC)) + iint->readcount--; + mutex_unlock(&iint->mutex); +} + +/* + * ima_counts_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 +285,14 @@ 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 +317,6 @@ 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 b5291ad5ef5..e1278399b34 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; } diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c index 7ec94314ac0..a0880e9c8e0 100644 --- a/security/integrity/ima/ima_queue.c +++ b/security/integrity/ima/ima_queue.c @@ -134,7 +134,8 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation, } out: mutex_unlock(&ima_extend_list_mutex); - integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, entry->template_name, + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, + entry->template.file_name, op, audit_cause, result, audit_info); return result; } diff --git a/security/lsm_audit.c b/security/lsm_audit.c new file mode 100644 index 00000000000..94b868494b3 --- /dev/null +++ b/security/lsm_audit.c @@ -0,0 +1,386 @@ +/* + * common LSM auditing functions + * + * Based on code written for SELinux by : + * Stephen Smalley, <sds@epoch.ncsc.mil> + * James Morris <jmorris@redhat.com> + * Author : Etienne Basset, <etienne.basset@ensta.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, + * as published by the Free Software Foundation. + */ + +#include <linux/types.h> +#include <linux/stddef.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <net/sock.h> +#include <linux/un.h> +#include <net/af_unix.h> +#include <linux/audit.h> +#include <linux/ipv6.h> +#include <linux/ip.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/dccp.h> +#include <linux/sctp.h> +#include <linux/lsm_audit.h> + +/** + * ipv4_skb_to_auditdata : fill auditdata from skb + * @skb : the skb + * @ad : the audit data to fill + * @proto : the layer 4 protocol + * + * return 0 on success + */ +int ipv4_skb_to_auditdata(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto) +{ + int ret = 0; + struct iphdr *ih; + + ih = ip_hdr(skb); + if (ih == NULL) + return -EINVAL; + + ad->u.net.v4info.saddr = ih->saddr; + ad->u.net.v4info.daddr = ih->daddr; + + if (proto) + *proto = ih->protocol; + /* non initial fragment */ + if (ntohs(ih->frag_off) & IP_OFFSET) + return 0; + + switch (ih->protocol) { + case IPPROTO_TCP: { + struct tcphdr *th = tcp_hdr(skb); + if (th == NULL) + break; + + ad->u.net.sport = th->source; + ad->u.net.dport = th->dest; + break; + } + case IPPROTO_UDP: { + struct udphdr *uh = udp_hdr(skb); + if (uh == NULL) + break; + + ad->u.net.sport = uh->source; + ad->u.net.dport = uh->dest; + break; + } + case IPPROTO_DCCP: { + struct dccp_hdr *dh = dccp_hdr(skb); + if (dh == NULL) + break; + + ad->u.net.sport = dh->dccph_sport; + ad->u.net.dport = dh->dccph_dport; + break; + } + case IPPROTO_SCTP: { + struct sctphdr *sh = sctp_hdr(skb); + if (sh == NULL) + break; + ad->u.net.sport = sh->source; + ad->u.net.dport = sh->dest; + break; + } + default: + ret = -EINVAL; + } + return ret; +} +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) +/** + * ipv6_skb_to_auditdata : fill auditdata from skb + * @skb : the skb + * @ad : the audit data to fill + * @proto : the layer 4 protocol + * + * return 0 on success + */ +int ipv6_skb_to_auditdata(struct sk_buff *skb, + struct common_audit_data *ad, u8 *proto) +{ + int offset, ret = 0; + struct ipv6hdr *ip6; + u8 nexthdr; + + ip6 = ipv6_hdr(skb); + if (ip6 == NULL) + return -EINVAL; + ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); + ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); + ret = 0; + /* IPv6 can have several extension header before the Transport header + * skip them */ + offset = skb_network_offset(skb); + offset += sizeof(*ip6); + nexthdr = ip6->nexthdr; + offset = ipv6_skip_exthdr(skb, offset, &nexthdr); + if (offset < 0) + return 0; + if (proto) + *proto = nexthdr; + switch (nexthdr) { + case IPPROTO_TCP: { + struct tcphdr _tcph, *th; + + th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); + if (th == NULL) + break; + + ad->u.net.sport = th->source; + ad->u.net.dport = th->dest; + break; + } + case IPPROTO_UDP: { + struct udphdr _udph, *uh; + + uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); + if (uh == NULL) + break; + + ad->u.net.sport = uh->source; + ad->u.net.dport = uh->dest; + break; + } + case IPPROTO_DCCP: { + struct dccp_hdr _dccph, *dh; + + dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); + if (dh == NULL) + break; + + ad->u.net.sport = dh->dccph_sport; + ad->u.net.dport = dh->dccph_dport; + break; + } + case IPPROTO_SCTP: { + struct sctphdr _sctph, *sh; + + sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph); + if (sh == NULL) + break; + ad->u.net.sport = sh->source; + ad->u.net.dport = sh->dest; + break; + } + default: + ret = -EINVAL; + } + return ret; +} +#endif + + +static inline void print_ipv6_addr(struct audit_buffer *ab, + struct in6_addr *addr, __be16 port, + char *name1, char *name2) +{ + if (!ipv6_addr_any(addr)) + audit_log_format(ab, " %s=%pI6", name1, addr); + if (port) + audit_log_format(ab, " %s=%d", name2, ntohs(port)); +} + +static inline void print_ipv4_addr(struct audit_buffer *ab, __be32 addr, + __be16 port, char *name1, char *name2) +{ + if (addr) + audit_log_format(ab, " %s=%pI4", name1, &addr); + if (port) + audit_log_format(ab, " %s=%d", name2, ntohs(port)); +} + +/** + * dump_common_audit_data - helper to dump common audit data + * @a : common audit data + * + */ +static void dump_common_audit_data(struct audit_buffer *ab, + struct common_audit_data *a) +{ + struct inode *inode = NULL; + struct task_struct *tsk = current; + + if (a->tsk) + tsk = a->tsk; + if (tsk && tsk->pid) { + audit_log_format(ab, " pid=%d comm=", tsk->pid); + audit_log_untrustedstring(ab, tsk->comm); + } + + switch (a->type) { + case LSM_AUDIT_DATA_IPC: + audit_log_format(ab, " key=%d ", a->u.ipc_id); + break; + case LSM_AUDIT_DATA_CAP: + audit_log_format(ab, " capability=%d ", a->u.cap); + break; + case LSM_AUDIT_DATA_FS: + if (a->u.fs.path.dentry) { + struct dentry *dentry = a->u.fs.path.dentry; + if (a->u.fs.path.mnt) { + audit_log_d_path(ab, "path=", &a->u.fs.path); + } else { + audit_log_format(ab, " name="); + audit_log_untrustedstring(ab, + dentry->d_name.name); + } + inode = dentry->d_inode; + } else if (a->u.fs.inode) { + struct dentry *dentry; + inode = a->u.fs.inode; + dentry = d_find_alias(inode); + if (dentry) { + audit_log_format(ab, " name="); + audit_log_untrustedstring(ab, + dentry->d_name.name); + dput(dentry); + } + } + if (inode) + audit_log_format(ab, " dev=%s ino=%lu", + inode->i_sb->s_id, + inode->i_ino); + break; + case LSM_AUDIT_DATA_TASK: + tsk = a->u.tsk; + if (tsk && tsk->pid) { + audit_log_format(ab, " pid=%d comm=", tsk->pid); + audit_log_untrustedstring(ab, tsk->comm); + } + break; + case LSM_AUDIT_DATA_NET: + if (a->u.net.sk) { + struct sock *sk = a->u.net.sk; + struct unix_sock *u; + int len = 0; + char *p = NULL; + + switch (sk->sk_family) { + case AF_INET: { + struct inet_sock *inet = inet_sk(sk); + + print_ipv4_addr(ab, inet->rcv_saddr, + inet->sport, + "laddr", "lport"); + print_ipv4_addr(ab, inet->daddr, + inet->dport, + "faddr", "fport"); + break; + } + case AF_INET6: { + struct inet_sock *inet = inet_sk(sk); + struct ipv6_pinfo *inet6 = inet6_sk(sk); + + print_ipv6_addr(ab, &inet6->rcv_saddr, + inet->sport, + "laddr", "lport"); + print_ipv6_addr(ab, &inet6->daddr, + inet->dport, + "faddr", "fport"); + break; + } + case AF_UNIX: + u = unix_sk(sk); + if (u->dentry) { + struct path path = { + .dentry = u->dentry, + .mnt = u->mnt + }; + audit_log_d_path(ab, "path=", &path); + break; + } + if (!u->addr) + break; + len = u->addr->len-sizeof(short); + p = &u->addr->name->sun_path[0]; + audit_log_format(ab, " path="); + if (*p) + audit_log_untrustedstring(ab, p); + else + audit_log_n_hex(ab, p, len); + break; + } + } + + switch (a->u.net.family) { + case AF_INET: + print_ipv4_addr(ab, a->u.net.v4info.saddr, + a->u.net.sport, + "saddr", "src"); + print_ipv4_addr(ab, a->u.net.v4info.daddr, + a->u.net.dport, + "daddr", "dest"); + break; + case AF_INET6: + print_ipv6_addr(ab, &a->u.net.v6info.saddr, + a->u.net.sport, + "saddr", "src"); + print_ipv6_addr(ab, &a->u.net.v6info.daddr, + a->u.net.dport, + "daddr", "dest"); + break; + } + if (a->u.net.netif > 0) { + struct net_device *dev; + + /* NOTE: we always use init's namespace */ + dev = dev_get_by_index(&init_net, a->u.net.netif); + if (dev) { + audit_log_format(ab, " netif=%s", dev->name); + dev_put(dev); + } + } + break; +#ifdef CONFIG_KEYS + case LSM_AUDIT_DATA_KEY: + audit_log_format(ab, " key_serial=%u", a->u.key_struct.key); + if (a->u.key_struct.key_desc) { + audit_log_format(ab, " key_desc="); + audit_log_untrustedstring(ab, a->u.key_struct.key_desc); + } + break; +#endif + } /* switch (a->type) */ +} + +/** + * common_lsm_audit - generic LSM auditing function + * @a: auxiliary audit data + * + * setup the audit buffer for common security information + * uses callback to print LSM specific information + */ +void common_lsm_audit(struct common_audit_data *a) +{ + struct audit_buffer *ab; + + if (a == NULL) + return; + /* we use GFP_ATOMIC so we won't sleep */ + ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_AVC); + + if (ab == NULL) + return; + + if (a->lsm_pre_audit) + a->lsm_pre_audit(ab, a); + + dump_common_audit_data(ab, a); + + if (a->lsm_post_audit) + a->lsm_post_audit(ab, a); + + audit_log_end(ab); +} diff --git a/security/root_plug.c b/security/root_plug.c index 40fb4f15e27..2f7ffa67c4d 100644 --- a/security/root_plug.c +++ b/security/root_plug.c @@ -71,18 +71,6 @@ static int rootplug_bprm_check_security (struct linux_binprm *bprm) } static struct security_operations rootplug_security_ops = { - /* Use the capability functions for some of the hooks */ - .ptrace_may_access = cap_ptrace_may_access, - .ptrace_traceme = cap_ptrace_traceme, - .capget = cap_capget, - .capset = cap_capset, - .capable = cap_capable, - - .bprm_set_creds = cap_bprm_set_creds, - - .task_fix_setuid = cap_task_fix_setuid, - .task_prctl = cap_task_prctl, - .bprm_check_security = rootplug_bprm_check_security, }; diff --git a/security/security.c b/security/security.c index 5284255c5cd..dc7674fbfc7 100644 --- a/security/security.c +++ b/security/security.c @@ -26,9 +26,6 @@ extern void security_fixup_ops(struct security_operations *ops); struct security_operations *security_ops; /* Initialized to NULL */ -/* amount of vm to protect from userspace access */ -unsigned long mmap_min_addr = CONFIG_SECURITY_DEFAULT_MMAP_MIN_ADDR; - static inline int verify(struct security_operations *ops) { /* verify the security_operations structure exists */ diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 7f9b5fac877..b2ab6085983 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -927,7 +927,7 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid, if (denied) { if (flags & AVC_STRICT) rc = -EACCES; - else if (!selinux_enforcing || security_permissive_sid(ssid)) + else if (!selinux_enforcing || (avd->flags & AVD_FLAGS_PERMISSIVE)) avc_update_node(AVC_CALLBACK_GRANT, requested, ssid, tsid, tclass, avd->seqno); else diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 2fcad7c33ea..15c2a08a66f 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1980,10 +1980,6 @@ static int selinux_sysctl(ctl_table *table, int op) u32 tsid, sid; int rc; - rc = secondary_ops->sysctl(table, op); - if (rc) - return rc; - sid = current_sid(); rc = selinux_sysctl_get_sid(table, (op == 0001) ? @@ -2375,10 +2371,8 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) { const struct task_security_struct *tsec = current_security(); struct itimerval itimer; - struct sighand_struct *psig; u32 osid, sid; int rc, i; - unsigned long flags; osid = tsec->osid; sid = tsec->sid; @@ -2398,22 +2392,20 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) memset(&itimer, 0, sizeof itimer); for (i = 0; i < 3; i++) do_setitimer(i, &itimer, NULL); - flush_signals(current); spin_lock_irq(¤t->sighand->siglock); - flush_signal_handlers(current, 1); - sigemptyset(¤t->blocked); - recalc_sigpending(); + if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { + __flush_signals(current); + flush_signal_handlers(current, 1); + sigemptyset(¤t->blocked); + } spin_unlock_irq(¤t->sighand->siglock); } /* Wake up the parent if it is waiting so that it can recheck * wait permission to the new task SID. */ - read_lock_irq(&tasklist_lock); - psig = current->parent->sighand; - spin_lock_irqsave(&psig->siglock, flags); - wake_up_interruptible(¤t->parent->signal->wait_chldexit); - spin_unlock_irqrestore(&psig->siglock, flags); - read_unlock_irq(&tasklist_lock); + read_lock(&tasklist_lock); + wake_up_interruptible(¤t->real_parent->signal->wait_chldexit); + read_unlock(&tasklist_lock); } /* superblock security operations */ @@ -4503,7 +4495,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, * when the packet is on it's final way out. * NOTE: there appear to be some IPv6 multicast cases where skb->dst * is NULL, in this case go ahead and apply access control. */ - if (skb->dst != NULL && skb->dst->xfrm != NULL) + if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) return NF_ACCEPT; #endif secmark_active = selinux_secmark_enabled(); diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 5c3434f7626..ca835795a8b 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -8,14 +8,13 @@ #ifndef _SELINUX_SECURITY_H_ #define _SELINUX_SECURITY_H_ +#include <linux/magic.h> #include "flask.h" #define SECSID_NULL 0x00000000 /* unspecified SID */ #define SECSID_WILD 0xffffffff /* wildcard SID */ #define SECCLASS_NULL 0x0000 /* no class */ -#define SELINUX_MAGIC 0xf97cff8c - /* Identify specific policy version changes */ #define POLICYDB_VERSION_BASE 15 #define POLICYDB_VERSION_BOOL 16 @@ -91,9 +90,11 @@ struct av_decision { u32 auditallow; u32 auditdeny; u32 seqno; + u32 flags; }; -int security_permissive_sid(u32 sid); +/* definitions of av_decision.flags */ +#define AVD_FLAGS_PERMISSIVE 0x0001 int security_compute_av(u32 ssid, u32 tsid, u16 tclass, u32 requested, diff --git a/security/selinux/nlmsgtab.c b/security/selinux/nlmsgtab.c index c6875fd3b9d..dd7cc6de77f 100644 --- a/security/selinux/nlmsgtab.c +++ b/security/selinux/nlmsgtab.c @@ -112,6 +112,8 @@ static struct nlmsg_perm nlmsg_audit_perms[] = { AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE }, { AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY }, { AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ }, + { AUDIT_TRIM, NETLINK_AUDIT_SOCKET__NLMSG_WRITE }, + { AUDIT_MAKE_EQUIV, NETLINK_AUDIT_SOCKET__NLMSG_WRITE }, { AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ }, { AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_TTY_AUDIT }, }; diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 2d5136ec3d5..b4fc506e7a8 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -527,10 +527,10 @@ static ssize_t sel_write_access(struct file *file, char *buf, size_t size) goto out2; length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, - "%x %x %x %x %u", + "%x %x %x %x %u %x", avd.allowed, 0xffffffff, avd.auditallow, avd.auditdeny, - avd.seqno); + avd.seqno, avd.flags); out2: kfree(tcon); out: @@ -803,10 +803,6 @@ static ssize_t sel_read_bool(struct file *filep, char __user *buf, goto out; } - if (count > PAGE_SIZE) { - ret = -EINVAL; - goto out; - } page = (char *)get_zeroed_page(GFP_KERNEL); if (!page) { ret = -ENOMEM; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index deeec6c013a..500e6f78e11 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -410,6 +410,7 @@ static int context_struct_compute_av(struct context *scontext, avd->auditallow = 0; avd->auditdeny = 0xffffffff; avd->seqno = latest_granting; + avd->flags = 0; /* * Check for all the invalid cases. @@ -528,31 +529,6 @@ inval_class: return 0; } -/* - * Given a sid find if the type has the permissive flag set - */ -int security_permissive_sid(u32 sid) -{ - struct context *context; - u32 type; - int rc; - - read_lock(&policy_rwlock); - - context = sidtab_search(&sidtab, sid); - BUG_ON(!context); - - type = context->type; - /* - * we are intentionally using type here, not type-1, the 0th bit may - * someday indicate that we are globally setting permissive in policy. - */ - rc = ebitmap_get_bit(&policydb.permissive_map, type); - - read_unlock(&policy_rwlock); - return rc; -} - static int security_validtrans_handle_fail(struct context *ocontext, struct context *ncontext, struct context *tcontext, @@ -767,6 +743,10 @@ int security_compute_av(u32 ssid, rc = context_struct_compute_av(scontext, tcontext, tclass, requested, avd); + + /* permissive domain? */ + if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) + avd->flags |= AVD_FLAGS_PERMISSIVE; out: read_unlock(&policy_rwlock); return rc; diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c index c0eb72013d6..72b18452e1a 100644 --- a/security/selinux/xfrm.c +++ b/security/selinux/xfrm.c @@ -447,7 +447,7 @@ int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb, struct dst_entry *dst; int rc = 0; - dst = skb->dst; + dst = skb_dst(skb); if (dst) { struct dst_entry *dst_test; diff --git a/security/smack/smack.h b/security/smack/smack.h index 42ef313f985..243bec175be 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -20,6 +20,7 @@ #include <net/netlabel.h> #include <linux/list.h> #include <linux/rculist.h> +#include <linux/lsm_audit.h> /* * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is @@ -179,6 +180,20 @@ struct smack_known { #define MAY_NOT 0 /* + * Number of access types used by Smack (rwxa) + */ +#define SMK_NUM_ACCESS_TYPE 4 + +/* + * Smack audit data; is empty if CONFIG_AUDIT not set + * to save some stack + */ +struct smk_audit_info { +#ifdef CONFIG_AUDIT + struct common_audit_data a; +#endif +}; +/* * These functions are in smack_lsm.c */ struct inode_smack *new_inode_smack(char *); @@ -186,8 +201,8 @@ struct inode_smack *new_inode_smack(char *); /* * These functions are in smack_access.c */ -int smk_access(char *, char *, int); -int smk_curacc(char *, u32); +int smk_access(char *, char *, int, struct smk_audit_info *); +int smk_curacc(char *, u32, struct smk_audit_info *); int smack_to_cipso(const char *, struct smack_cipso *); void smack_from_cipso(u32, char *, char *); char *smack_from_secid(const u32); @@ -237,4 +252,93 @@ static inline char *smk_of_inode(const struct inode *isp) return sip->smk_inode; } +/* + * logging functions + */ +#define SMACK_AUDIT_DENIED 0x1 +#define SMACK_AUDIT_ACCEPT 0x2 +extern int log_policy; + +void smack_log(char *subject_label, char *object_label, + int request, + int result, struct smk_audit_info *auditdata); + +#ifdef CONFIG_AUDIT + +/* + * some inline functions to set up audit data + * they do nothing if CONFIG_AUDIT is not set + * + */ +static inline void smk_ad_init(struct smk_audit_info *a, const char *func, + char type) +{ + memset(a, 0, sizeof(*a)); + a->a.type = type; + a->a.function = func; +} + +static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, + struct task_struct *t) +{ + a->a.u.tsk = t; +} +static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, + struct dentry *d) +{ + a->a.u.fs.path.dentry = d; +} +static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, + struct vfsmount *m) +{ + a->a.u.fs.path.mnt = m; +} +static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, + struct inode *i) +{ + a->a.u.fs.inode = i; +} +static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, + struct path p) +{ + a->a.u.fs.path = p; +} +static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, + struct sock *sk) +{ + a->a.u.net.sk = sk; +} + +#else /* no AUDIT */ + +static inline void smk_ad_init(struct smk_audit_info *a, const char *func, + char type) +{ +} +static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, + struct task_struct *t) +{ +} +static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, + struct dentry *d) +{ +} +static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, + struct vfsmount *m) +{ +} +static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, + struct inode *i) +{ +} +static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, + struct path p) +{ +} +static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, + struct sock *sk) +{ +} +#endif + #endif /* _SECURITY_SMACK_H */ diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index ac0a2707f6d..513dc1aa16d 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -59,11 +59,18 @@ LIST_HEAD(smack_known_list); */ static u32 smack_next_secid = 10; +/* + * what events do we log + * can be overwritten at run-time by /smack/logging + */ +int log_policy = SMACK_AUDIT_DENIED; + /** * smk_access - determine if a subject has a specific access to an object * @subject_label: a pointer to the subject's Smack label * @object_label: a pointer to the object's Smack label * @request: the access requested, in "MAY" format + * @a : a pointer to the audit data * * This function looks up the subject/object pair in the * access rule list and returns 0 if the access is permitted, @@ -78,10 +85,12 @@ static u32 smack_next_secid = 10; * will be on the list, so checking the pointers may be a worthwhile * optimization. */ -int smk_access(char *subject_label, char *object_label, int request) +int smk_access(char *subject_label, char *object_label, int request, + struct smk_audit_info *a) { u32 may = MAY_NOT; struct smack_rule *srp; + int rc = 0; /* * Hardcoded comparisons. @@ -89,8 +98,10 @@ int smk_access(char *subject_label, char *object_label, int request) * A star subject can't access any object. */ if (subject_label == smack_known_star.smk_known || - strcmp(subject_label, smack_known_star.smk_known) == 0) - return -EACCES; + strcmp(subject_label, smack_known_star.smk_known) == 0) { + rc = -EACCES; + goto out_audit; + } /* * An internet object can be accessed by any subject. * Tasks cannot be assigned the internet label. @@ -100,20 +111,20 @@ int smk_access(char *subject_label, char *object_label, int request) subject_label == smack_known_web.smk_known || strcmp(object_label, smack_known_web.smk_known) == 0 || strcmp(subject_label, smack_known_web.smk_known) == 0) - return 0; + goto out_audit; /* * A star object can be accessed by any subject. */ if (object_label == smack_known_star.smk_known || strcmp(object_label, smack_known_star.smk_known) == 0) - return 0; + goto out_audit; /* * An object can be accessed in any way by a subject * with the same label. */ if (subject_label == object_label || strcmp(subject_label, object_label) == 0) - return 0; + goto out_audit; /* * A hat subject can read any object. * A floor object can be read by any subject. @@ -121,10 +132,10 @@ int smk_access(char *subject_label, char *object_label, int request) if ((request & MAY_ANYREAD) == request) { if (object_label == smack_known_floor.smk_known || strcmp(object_label, smack_known_floor.smk_known) == 0) - return 0; + goto out_audit; if (subject_label == smack_known_hat.smk_known || strcmp(subject_label, smack_known_hat.smk_known) == 0) - return 0; + goto out_audit; } /* * Beyond here an explicit relationship is required. @@ -148,28 +159,36 @@ int smk_access(char *subject_label, char *object_label, int request) * This is a bit map operation. */ if ((request & may) == request) - return 0; - - return -EACCES; + goto out_audit; + + rc = -EACCES; +out_audit: +#ifdef CONFIG_AUDIT + if (a) + smack_log(subject_label, object_label, request, rc, a); +#endif + return rc; } /** * smk_curacc - determine if current has a specific access to an object * @obj_label: a pointer to the object's Smack label * @mode: the access requested, in "MAY" format + * @a : common audit data * * This function checks the current subject label/object label pair * in the access rule list and returns 0 if the access is permitted, * non zero otherwise. It allows that current may have the capability * to override the rules. */ -int smk_curacc(char *obj_label, u32 mode) +int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) { int rc; + char *sp = current_security(); - rc = smk_access(current_security(), obj_label, mode); + rc = smk_access(sp, obj_label, mode, NULL); if (rc == 0) - return 0; + goto out_audit; /* * Return if a specific label has been designated as the @@ -177,14 +196,105 @@ int smk_curacc(char *obj_label, u32 mode) * have that label. */ if (smack_onlycap != NULL && smack_onlycap != current->cred->security) - return rc; + goto out_audit; if (capable(CAP_MAC_OVERRIDE)) return 0; +out_audit: +#ifdef CONFIG_AUDIT + if (a) + smack_log(sp, obj_label, mode, rc, a); +#endif return rc; } +#ifdef CONFIG_AUDIT +/** + * smack_str_from_perm : helper to transalate an int to a + * readable string + * @string : the string to fill + * @access : the int + * + */ +static inline void smack_str_from_perm(char *string, int access) +{ + int i = 0; + if (access & MAY_READ) + string[i++] = 'r'; + if (access & MAY_WRITE) + string[i++] = 'w'; + if (access & MAY_EXEC) + string[i++] = 'x'; + if (access & MAY_APPEND) + string[i++] = 'a'; + string[i] = '\0'; +} +/** + * smack_log_callback - SMACK specific information + * will be called by generic audit code + * @ab : the audit_buffer + * @a : audit_data + * + */ +static void smack_log_callback(struct audit_buffer *ab, void *a) +{ + struct common_audit_data *ad = a; + struct smack_audit_data *sad = &ad->lsm_priv.smack_audit_data; + audit_log_format(ab, "lsm=SMACK fn=%s action=%s", ad->function, + sad->result ? "denied" : "granted"); + audit_log_format(ab, " subject="); + audit_log_untrustedstring(ab, sad->subject); + audit_log_format(ab, " object="); + audit_log_untrustedstring(ab, sad->object); + audit_log_format(ab, " requested=%s", sad->request); +} + +/** + * smack_log - Audit the granting or denial of permissions. + * @subject_label : smack label of the requester + * @object_label : smack label of the object being accessed + * @request: requested permissions + * @result: result from smk_access + * @a: auxiliary audit data + * + * Audit the granting or denial of permissions in accordance + * with the policy. + */ +void smack_log(char *subject_label, char *object_label, int request, + int result, struct smk_audit_info *ad) +{ + char request_buffer[SMK_NUM_ACCESS_TYPE + 1]; + struct smack_audit_data *sad; + struct common_audit_data *a = &ad->a; + + /* check if we have to log the current event */ + if (result != 0 && (log_policy & SMACK_AUDIT_DENIED) == 0) + return; + if (result == 0 && (log_policy & SMACK_AUDIT_ACCEPT) == 0) + return; + + if (a->function == NULL) + a->function = "unknown"; + + /* end preparing the audit data */ + sad = &a->lsm_priv.smack_audit_data; + smack_str_from_perm(request_buffer, request); + sad->subject = subject_label; + sad->object = object_label; + sad->request = request_buffer; + sad->result = result; + a->lsm_pre_audit = smack_log_callback; + + common_lsm_audit(a); +} +#else /* #ifdef CONFIG_AUDIT */ +void smack_log(char *subject_label, char *object_label, int request, + int result, struct smk_audit_info *ad) +{ +} +#endif + static DEFINE_MUTEX(smack_known_lock); /** @@ -209,7 +319,8 @@ struct smack_known *smk_import_entry(const char *string, int len) if (found) smack[i] = '\0'; else if (i >= len || string[i] > '~' || string[i] <= ' ' || - string[i] == '/') { + string[i] == '/' || string[i] == '"' || + string[i] == '\\' || string[i] == '\'') { smack[i] = '\0'; found = 1; } else diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 98b3195347a..0023182078c 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -30,7 +30,6 @@ #include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <linux/audit.h> - #include "smack.h" #define task_security(task) (task_cred_xxx((task), security)) @@ -103,14 +102,24 @@ struct inode_smack *new_inode_smack(char *smack) static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode) { int rc; + struct smk_audit_info ad; + char *sp, *tsp; rc = cap_ptrace_may_access(ctp, mode); if (rc != 0) return rc; - rc = smk_access(current_security(), task_security(ctp), MAY_READWRITE); + sp = current_security(); + tsp = task_security(ctp); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, ctp); + + /* we won't log here, because rc can be overriden */ + rc = smk_access(sp, tsp, MAY_READWRITE, NULL); if (rc != 0 && capable(CAP_MAC_OVERRIDE)) - return 0; + rc = 0; + + smack_log(sp, tsp, MAY_READWRITE, rc, &ad); return rc; } @@ -125,14 +134,24 @@ static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode) static int smack_ptrace_traceme(struct task_struct *ptp) { int rc; + struct smk_audit_info ad; + char *sp, *tsp; rc = cap_ptrace_traceme(ptp); if (rc != 0) return rc; - rc = smk_access(task_security(ptp), current_security(), MAY_READWRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, ptp); + + sp = current_security(); + tsp = task_security(ptp); + /* we won't log here, because rc can be overriden */ + rc = smk_access(tsp, sp, MAY_READWRITE, NULL); if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE)) - return 0; + rc = 0; + + smack_log(tsp, sp, MAY_READWRITE, rc, &ad); return rc; } @@ -327,8 +346,14 @@ static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data) static int smack_sb_statfs(struct dentry *dentry) { struct superblock_smack *sbp = dentry->d_sb->s_security; + int rc; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); - return smk_curacc(sbp->smk_floor, MAY_READ); + rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad); + return rc; } /** @@ -346,8 +371,12 @@ static int smack_sb_mount(char *dev_name, struct path *path, char *type, unsigned long flags, void *data) { struct superblock_smack *sbp = path->mnt->mnt_sb->s_security; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path(&ad, *path); - return smk_curacc(sbp->smk_floor, MAY_WRITE); + return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad); } /** @@ -361,10 +390,14 @@ static int smack_sb_mount(char *dev_name, struct path *path, static int smack_sb_umount(struct vfsmount *mnt, int flags) { struct superblock_smack *sbp; + struct smk_audit_info ad; - sbp = mnt->mnt_sb->s_security; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, mnt->mnt_mountpoint); + smk_ad_setfield_u_fs_path_mnt(&ad, mnt); - return smk_curacc(sbp->smk_floor, MAY_WRITE); + sbp = mnt->mnt_sb->s_security; + return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad); } /* @@ -441,15 +474,20 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) { - int rc; char *isp; + struct smk_audit_info ad; + int rc; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); - rc = smk_curacc(isp, MAY_WRITE); + rc = smk_curacc(isp, MAY_WRITE, &ad); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); - rc = smk_curacc(isp, MAY_WRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); + rc = smk_curacc(isp, MAY_WRITE, &ad); } return rc; @@ -466,18 +504,24 @@ static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) { struct inode *ip = dentry->d_inode; + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + /* * You need write access to the thing you're unlinking */ - rc = smk_curacc(smk_of_inode(ip), MAY_WRITE); - if (rc == 0) + rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); + if (rc == 0) { /* * You also need write access to the containing directory */ - rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); - + smk_ad_setfield_u_fs_path_dentry(&ad, NULL); + smk_ad_setfield_u_fs_inode(&ad, dir); + rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); + } return rc; } @@ -491,17 +535,24 @@ static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) */ static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) { + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + /* * You need write access to the thing you're removing */ - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); - if (rc == 0) + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); + if (rc == 0) { /* * You also need write access to the containing directory */ - rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, NULL); + smk_ad_setfield_u_fs_inode(&ad, dir); + rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); + } return rc; } @@ -525,15 +576,19 @@ static int smack_inode_rename(struct inode *old_inode, { int rc; char *isp; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); - rc = smk_curacc(isp, MAY_READWRITE); + rc = smk_curacc(isp, MAY_READWRITE, &ad); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); - rc = smk_curacc(isp, MAY_READWRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); + rc = smk_curacc(isp, MAY_READWRITE, &ad); } - return rc; } @@ -548,13 +603,15 @@ static int smack_inode_rename(struct inode *old_inode, */ static int smack_inode_permission(struct inode *inode, int mask) { + struct smk_audit_info ad; /* * No permission to check. Existence test. Yup, it's there. */ if (mask == 0) return 0; - - return smk_curacc(smk_of_inode(inode), mask); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_inode(&ad, inode); + return smk_curacc(smk_of_inode(inode), mask, &ad); } /** @@ -566,13 +623,16 @@ static int smack_inode_permission(struct inode *inode, int mask) */ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) { + struct smk_audit_info ad; /* * Need to allow for clearing the setuid bit. */ if (iattr->ia_valid & ATTR_FORCE) return 0; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); } /** @@ -584,7 +644,12 @@ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) */ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) { - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + smk_ad_setfield_u_fs_path_mnt(&ad, mnt); + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); } /** @@ -602,6 +667,7 @@ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) static int smack_inode_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { + struct smk_audit_info ad; int rc = 0; if (strcmp(name, XATTR_NAME_SMACK) == 0 || @@ -619,8 +685,11 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name, } else rc = cap_inode_setxattr(dentry, name, value, size, flags); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + if (rc == 0) - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); return rc; } @@ -672,7 +741,12 @@ static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, */ static int smack_inode_getxattr(struct dentry *dentry, const char *name) { - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); } /* @@ -686,6 +760,7 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name) */ static int smack_inode_removexattr(struct dentry *dentry, const char *name) { + struct smk_audit_info ad; int rc = 0; if (strcmp(name, XATTR_NAME_SMACK) == 0 || @@ -696,8 +771,10 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) } else rc = cap_inode_removexattr(dentry, name); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); if (rc == 0) - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); return rc; } @@ -856,12 +933,16 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { int rc = 0; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path(&ad, file->f_path); if (_IOC_DIR(cmd) & _IOC_WRITE) - rc = smk_curacc(file->f_security, MAY_WRITE); + rc = smk_curacc(file->f_security, MAY_WRITE, &ad); if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) - rc = smk_curacc(file->f_security, MAY_READ); + rc = smk_curacc(file->f_security, MAY_READ, &ad); return rc; } @@ -875,7 +956,11 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd, */ static int smack_file_lock(struct file *file, unsigned int cmd) { - return smk_curacc(file->f_security, MAY_WRITE); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path_dentry(&ad, file->f_path.dentry); + return smk_curacc(file->f_security, MAY_WRITE, &ad); } /** @@ -889,8 +974,12 @@ static int smack_file_lock(struct file *file, unsigned int cmd) static int smack_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) { + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + switch (cmd) { case F_DUPFD: case F_GETFD: @@ -898,7 +987,7 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, case F_GETLK: case F_GETOWN: case F_GETSIG: - rc = smk_curacc(file->f_security, MAY_READ); + rc = smk_curacc(file->f_security, MAY_READ, &ad); break; case F_SETFD: case F_SETFL: @@ -906,10 +995,10 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, case F_SETLKW: case F_SETOWN: case F_SETSIG: - rc = smk_curacc(file->f_security, MAY_WRITE); + rc = smk_curacc(file->f_security, MAY_WRITE, &ad); break; default: - rc = smk_curacc(file->f_security, MAY_READWRITE); + rc = smk_curacc(file->f_security, MAY_READWRITE, &ad); } return rc; @@ -944,14 +1033,21 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, { struct file *file; int rc; + char *tsp = tsk->cred->security; + struct smk_audit_info ad; /* * struct fown_struct is never outside the context of a struct file */ file = container_of(fown, struct file, f_owner); - rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE); + /* we don't log here as rc can be overriden */ + rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL); if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) - return 0; + rc = 0; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, tsk); + smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad); return rc; } @@ -964,7 +1060,10 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, static int smack_file_receive(struct file *file) { int may = 0; + struct smk_audit_info ad; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_fs_path(&ad, file->f_path); /* * This code relies on bitmasks. */ @@ -973,7 +1072,7 @@ static int smack_file_receive(struct file *file) if (file->f_mode & FMODE_WRITE) may |= MAY_WRITE; - return smk_curacc(file->f_security, may); + return smk_curacc(file->f_security, may, &ad); } /* @@ -1053,6 +1152,22 @@ static int smack_kernel_create_files_as(struct cred *new, } /** + * smk_curacc_on_task - helper to log task related access + * @p: the task object + * @access : the access requested + * + * Return 0 if access is permitted + */ +static int smk_curacc_on_task(struct task_struct *p, int access) +{ + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); + return smk_curacc(task_security(p), access, &ad); +} + +/** * smack_task_setpgid - Smack check on setting pgid * @p: the task object * @pgid: unused @@ -1061,7 +1176,7 @@ static int smack_kernel_create_files_as(struct cred *new, */ static int smack_task_setpgid(struct task_struct *p, pid_t pgid) { - return smk_curacc(task_security(p), MAY_WRITE); + return smk_curacc_on_task(p, MAY_WRITE); } /** @@ -1072,7 +1187,7 @@ static int smack_task_setpgid(struct task_struct *p, pid_t pgid) */ static int smack_task_getpgid(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1083,7 +1198,7 @@ static int smack_task_getpgid(struct task_struct *p) */ static int smack_task_getsid(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1111,7 +1226,7 @@ static int smack_task_setnice(struct task_struct *p, int nice) rc = cap_task_setnice(p, nice); if (rc == 0) - rc = smk_curacc(task_security(p), MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE); return rc; } @@ -1128,7 +1243,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio) rc = cap_task_setioprio(p, ioprio); if (rc == 0) - rc = smk_curacc(task_security(p), MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE); return rc; } @@ -1140,7 +1255,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio) */ static int smack_task_getioprio(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1158,7 +1273,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy, rc = cap_task_setscheduler(p, policy, lp); if (rc == 0) - rc = smk_curacc(task_security(p), MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE); return rc; } @@ -1170,7 +1285,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy, */ static int smack_task_getscheduler(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_READ); + return smk_curacc_on_task(p, MAY_READ); } /** @@ -1181,7 +1296,7 @@ static int smack_task_getscheduler(struct task_struct *p) */ static int smack_task_movememory(struct task_struct *p) { - return smk_curacc(task_security(p), MAY_WRITE); + return smk_curacc_on_task(p, MAY_WRITE); } /** @@ -1199,18 +1314,23 @@ static int smack_task_movememory(struct task_struct *p) static int smack_task_kill(struct task_struct *p, struct siginfo *info, int sig, u32 secid) { + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); /* * Sending a signal requires that the sender * can write the receiver. */ if (secid == 0) - return smk_curacc(task_security(p), MAY_WRITE); + return smk_curacc(task_security(p), MAY_WRITE, &ad); /* * If the secid isn't 0 we're dealing with some USB IO * specific behavior. This is not clean. For one thing * we can't take privilege into account. */ - return smk_access(smack_from_secid(secid), task_security(p), MAY_WRITE); + return smk_access(smack_from_secid(secid), task_security(p), + MAY_WRITE, &ad); } /** @@ -1221,11 +1341,15 @@ static int smack_task_kill(struct task_struct *p, struct siginfo *info, */ static int smack_task_wait(struct task_struct *p) { + struct smk_audit_info ad; + char *sp = current_security(); + char *tsp = task_security(p); int rc; - rc = smk_access(current_security(), task_security(p), MAY_WRITE); + /* we don't log here, we can be overriden */ + rc = smk_access(sp, tsp, MAY_WRITE, NULL); if (rc == 0) - return 0; + goto out_log; /* * Allow the operation to succeed if either task @@ -1239,8 +1363,12 @@ static int smack_task_wait(struct task_struct *p) * the smack value. */ if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE)) - return 0; - + rc = 0; + /* we log only if we didn't get overriden */ + out_log: + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); + smack_log(sp, tsp, MAY_WRITE, rc, &ad); return rc; } @@ -1456,12 +1584,19 @@ static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap) int sk_lbl; char *hostsp; struct socket_smack *ssp = sk->sk_security; + struct smk_audit_info ad; rcu_read_lock(); hostsp = smack_host_label(sap); if (hostsp != NULL) { sk_lbl = SMACK_UNLABELED_SOCKET; - rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + ad.a.u.net.family = sap->sin_family; + ad.a.u.net.dport = sap->sin_port; + ad.a.u.net.v4info.daddr = sap->sin_addr.s_addr; +#endif + rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad); } else { sk_lbl = SMACK_CIPSO_SOCKET; rc = 0; @@ -1657,6 +1792,25 @@ static void smack_shm_free_security(struct shmid_kernel *shp) } /** + * smk_curacc_shm : check if current has access on shm + * @shp : the object + * @access : access requested + * + * Returns 0 if current has the requested access, error code otherwise + */ +static int smk_curacc_shm(struct shmid_kernel *shp, int access) +{ + char *ssp = smack_of_shm(shp); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = shp->shm_perm.id; +#endif + return smk_curacc(ssp, access, &ad); +} + +/** * smack_shm_associate - Smack access check for shm * @shp: the object * @shmflg: access requested @@ -1665,11 +1819,10 @@ static void smack_shm_free_security(struct shmid_kernel *shp) */ static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) { - char *ssp = smack_of_shm(shp); int may; may = smack_flags_to_may(shmflg); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1681,7 +1834,6 @@ static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) */ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) { - char *ssp; int may; switch (cmd) { @@ -1704,9 +1856,7 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) default: return -EINVAL; } - - ssp = smack_of_shm(shp); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1720,11 +1870,10 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, int shmflg) { - char *ssp = smack_of_shm(shp); int may; may = smack_flags_to_may(shmflg); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1766,6 +1915,25 @@ static void smack_sem_free_security(struct sem_array *sma) } /** + * smk_curacc_sem : check if current has access on sem + * @sma : the object + * @access : access requested + * + * Returns 0 if current has the requested access, error code otherwise + */ +static int smk_curacc_sem(struct sem_array *sma, int access) +{ + char *ssp = smack_of_sem(sma); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = sma->sem_perm.id; +#endif + return smk_curacc(ssp, access, &ad); +} + +/** * smack_sem_associate - Smack access check for sem * @sma: the object * @semflg: access requested @@ -1774,11 +1942,10 @@ static void smack_sem_free_security(struct sem_array *sma) */ static int smack_sem_associate(struct sem_array *sma, int semflg) { - char *ssp = smack_of_sem(sma); int may; may = smack_flags_to_may(semflg); - return smk_curacc(ssp, may); + return smk_curacc_sem(sma, may); } /** @@ -1790,7 +1957,6 @@ static int smack_sem_associate(struct sem_array *sma, int semflg) */ static int smack_sem_semctl(struct sem_array *sma, int cmd) { - char *ssp; int may; switch (cmd) { @@ -1819,8 +1985,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) return -EINVAL; } - ssp = smack_of_sem(sma); - return smk_curacc(ssp, may); + return smk_curacc_sem(sma, may); } /** @@ -1837,9 +2002,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, unsigned nsops, int alter) { - char *ssp = smack_of_sem(sma); - - return smk_curacc(ssp, MAY_READWRITE); + return smk_curacc_sem(sma, MAY_READWRITE); } /** @@ -1881,6 +2044,25 @@ static char *smack_of_msq(struct msg_queue *msq) } /** + * smk_curacc_msq : helper to check if current has access on msq + * @msq : the msq + * @access : access requested + * + * return 0 if current has access, error otherwise + */ +static int smk_curacc_msq(struct msg_queue *msq, int access) +{ + char *msp = smack_of_msq(msq); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = msq->q_perm.id; +#endif + return smk_curacc(msp, access, &ad); +} + +/** * smack_msg_queue_associate - Smack access check for msg_queue * @msq: the object * @msqflg: access requested @@ -1889,11 +2071,10 @@ static char *smack_of_msq(struct msg_queue *msq) */ static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) { - char *msp = smack_of_msq(msq); int may; may = smack_flags_to_may(msqflg); - return smk_curacc(msp, may); + return smk_curacc_msq(msq, may); } /** @@ -1905,7 +2086,6 @@ static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) */ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) { - char *msp; int may; switch (cmd) { @@ -1927,8 +2107,7 @@ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) return -EINVAL; } - msp = smack_of_msq(msq); - return smk_curacc(msp, may); + return smk_curacc_msq(msq, may); } /** @@ -1942,11 +2121,10 @@ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) { - char *msp = smack_of_msq(msq); - int rc; + int may; - rc = smack_flags_to_may(msqflg); - return smk_curacc(msp, rc); + may = smack_flags_to_may(msqflg); + return smk_curacc_msq(msq, may); } /** @@ -1962,9 +2140,7 @@ static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, struct task_struct *target, long type, int mode) { - char *msp = smack_of_msq(msq); - - return smk_curacc(msp, MAY_READWRITE); + return smk_curacc_msq(msq, MAY_READWRITE); } /** @@ -1977,10 +2153,14 @@ static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) { char *isp = ipp->security; - int may; + int may = smack_flags_to_may(flag); + struct smk_audit_info ad; - may = smack_flags_to_may(flag); - return smk_curacc(isp, may); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = ipp->id; +#endif + return smk_curacc(isp, may, &ad); } /** @@ -2239,8 +2419,12 @@ static int smack_unix_stream_connect(struct socket *sock, { struct inode *sp = SOCK_INODE(sock); struct inode *op = SOCK_INODE(other); + struct smk_audit_info ad; - return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + smk_ad_setfield_u_net_sk(&ad, other->sk); + return smk_access(smk_of_inode(sp), smk_of_inode(op), + MAY_READWRITE, &ad); } /** @@ -2255,8 +2439,11 @@ static int smack_unix_may_send(struct socket *sock, struct socket *other) { struct inode *sp = SOCK_INODE(sock); struct inode *op = SOCK_INODE(other); + struct smk_audit_info ad; - return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + smk_ad_setfield_u_net_sk(&ad, other->sk); + return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE, &ad); } /** @@ -2371,7 +2558,7 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) char smack[SMK_LABELLEN]; char *csp; int rc; - + struct smk_audit_info ad; if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) return 0; @@ -2389,13 +2576,19 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) netlbl_secattr_destroy(&secattr); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + ad.a.u.net.family = sk->sk_family; + ad.a.u.net.netif = skb->iif; + ipv4_skb_to_auditdata(skb, &ad.a, NULL); +#endif /* * Receiving a packet requires that the other end * be able to write here. Read access is not required. * This is the simplist possible security model * for networking. */ - rc = smk_access(csp, ssp->smk_in, MAY_WRITE); + rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad); if (rc != 0) netlbl_skbuff_err(skb, rc, 0); return rc; @@ -2524,6 +2717,7 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, struct iphdr *hdr; char smack[SMK_LABELLEN]; int rc; + struct smk_audit_info ad; /* handle mapped IPv4 packets arriving via IPv6 sockets */ if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) @@ -2537,11 +2731,17 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); netlbl_secattr_destroy(&secattr); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); + ad.a.u.net.family = family; + ad.a.u.net.netif = skb->iif; + ipv4_skb_to_auditdata(skb, &ad.a, NULL); +#endif /* * Receiving a packet requires that the other end be able to write * here. Read access is not required. */ - rc = smk_access(smack, ssp->smk_in, MAY_WRITE); + rc = smk_access(smack, ssp->smk_in, MAY_WRITE, &ad); if (rc != 0) return rc; @@ -2643,6 +2843,7 @@ static int smack_key_permission(key_ref_t key_ref, const struct cred *cred, key_perm_t perm) { struct key *keyp; + struct smk_audit_info ad; keyp = key_ref_to_ptr(key_ref); if (keyp == NULL) @@ -2658,8 +2859,13 @@ static int smack_key_permission(key_ref_t key_ref, */ if (cred->security == NULL) return -EACCES; - - return smk_access(cred->security, keyp->security, MAY_READWRITE); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); + ad.a.u.key_struct.key = keyp->serial; + ad.a.u.key_struct.key_desc = keyp->description; +#endif + return smk_access(cred->security, keyp->security, + MAY_READWRITE, &ad); } #endif /* CONFIG_KEYS */ @@ -2828,15 +3034,7 @@ struct security_operations smack_ops = { .ptrace_may_access = smack_ptrace_may_access, .ptrace_traceme = smack_ptrace_traceme, - .capget = cap_capget, - .capset = cap_capset, - .capable = cap_capable, .syslog = smack_syslog, - .settime = cap_settime, - .vm_enough_memory = cap_vm_enough_memory, - - .bprm_set_creds = cap_bprm_set_creds, - .bprm_secureexec = cap_bprm_secureexec, .sb_alloc_security = smack_sb_alloc_security, .sb_free_security = smack_sb_free_security, @@ -2860,8 +3058,6 @@ struct security_operations smack_ops = { .inode_post_setxattr = smack_inode_post_setxattr, .inode_getxattr = smack_inode_getxattr, .inode_removexattr = smack_inode_removexattr, - .inode_need_killpriv = cap_inode_need_killpriv, - .inode_killpriv = cap_inode_killpriv, .inode_getsecurity = smack_inode_getsecurity, .inode_setsecurity = smack_inode_setsecurity, .inode_listsecurity = smack_inode_listsecurity, @@ -2882,7 +3078,6 @@ struct security_operations smack_ops = { .cred_commit = smack_cred_commit, .kernel_act_as = smack_kernel_act_as, .kernel_create_files_as = smack_kernel_create_files_as, - .task_fix_setuid = cap_task_fix_setuid, .task_setpgid = smack_task_setpgid, .task_getpgid = smack_task_getpgid, .task_getsid = smack_task_getsid, @@ -2896,7 +3091,6 @@ struct security_operations smack_ops = { .task_kill = smack_task_kill, .task_wait = smack_task_wait, .task_to_inode = smack_task_to_inode, - .task_prctl = cap_task_prctl, .ipc_permission = smack_ipc_permission, .ipc_getsecid = smack_ipc_getsecid, @@ -2923,9 +3117,6 @@ struct security_operations smack_ops = { .sem_semctl = smack_sem_semctl, .sem_semop = smack_sem_semop, - .netlink_send = cap_netlink_send, - .netlink_recv = cap_netlink_recv, - .d_instantiate = smack_d_instantiate, .getprocattr = smack_getprocattr, diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 11d2cb19d7a..f83a8098072 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -41,6 +41,7 @@ enum smk_inos { SMK_AMBIENT = 7, /* internet ambient label */ SMK_NETLBLADDR = 8, /* single label hosts */ SMK_ONLYCAP = 9, /* the only "capable" label */ + SMK_LOGGING = 10, /* logging */ }; /* @@ -775,7 +776,7 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf, struct sockaddr_in newname; char smack[SMK_LABELLEN]; char *sp; - char data[SMK_NETLBLADDRMAX]; + char data[SMK_NETLBLADDRMAX + 1]; char *host = (char *)&newname.sin_addr.s_addr; int rc; struct netlbl_audit audit_info; @@ -1192,6 +1193,69 @@ static const struct file_operations smk_onlycap_ops = { }; /** + * smk_read_logging - read() for /smack/logging + * @filp: file pointer, not actually used + * @buf: where to put the result + * @cn: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_logging(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + ssize_t rc; + + if (*ppos != 0) + return 0; + + sprintf(temp, "%d\n", log_policy); + rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); + return rc; +} + +/** + * smk_write_logging - write() for /smack/logging + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_logging(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char temp[32]; + int i; + + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + if (count >= sizeof(temp) || count == 0) + return -EINVAL; + + if (copy_from_user(temp, buf, count) != 0) + return -EFAULT; + + temp[count] = '\0'; + + if (sscanf(temp, "%d", &i) != 1) + return -EINVAL; + if (i < 0 || i > 3) + return -EINVAL; + log_policy = i; + return count; +} + + + +static const struct file_operations smk_logging_ops = { + .read = smk_read_logging, + .write = smk_write_logging, +}; +/** * smk_fill_super - fill the /smackfs superblock * @sb: the empty superblock * @data: unused @@ -1221,6 +1285,8 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent) {"netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR}, [SMK_ONLYCAP] = {"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR}, + [SMK_LOGGING] = + {"logging", &smk_logging_ops, S_IRUGO|S_IWUSR}, /* last one */ {""} }; diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c index ddfb9cccf46..fdd1f4b8c44 100644 --- a/security/tomoyo/common.c +++ b/security/tomoyo/common.c @@ -28,7 +28,13 @@ static const char *tomoyo_mode_2[4] = { "disabled", "enabled", "enabled", "enabled" }; -/* Table for profile. */ +/* + * tomoyo_control_array is a static data which contains + * + * (1) functionality name used by /sys/kernel/security/tomoyo/profile . + * (2) initial values for "struct tomoyo_profile". + * (3) max values for "struct tomoyo_profile". + */ static struct { const char *keyword; unsigned int current_value; @@ -39,7 +45,13 @@ static struct { [TOMOYO_VERBOSE] = { "TOMOYO_VERBOSE", 1, 1 }, }; -/* Profile table. Memory is allocated as needed. */ +/* + * tomoyo_profile is a structure which is used for holding the mode of access + * controls. TOMOYO has 4 modes: disabled, learning, permissive, enforcing. + * An administrator can define up to 256 profiles. + * The ->profile of "struct tomoyo_domain_info" is used for remembering + * the profile's number (0 - 255) assigned to that domain. + */ static struct tomoyo_profile { unsigned int value[TOMOYO_MAX_CONTROL_INDEX]; const struct tomoyo_path_info *comment; @@ -428,7 +440,6 @@ void tomoyo_fill_path_info(struct tomoyo_path_info *ptr) const char *name = ptr->name; const int len = strlen(name); - ptr->total_len = len; ptr->const_len = tomoyo_const_part_length(name); ptr->is_dir = len && (name[len - 1] == '/'); ptr->is_patterned = (ptr->const_len < len); @@ -866,7 +877,6 @@ static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned if (profile >= TOMOYO_MAX_PROFILES) return NULL; - /***** EXCLUSIVE SECTION START *****/ mutex_lock(&lock); ptr = tomoyo_profile_ptr[profile]; if (ptr) @@ -880,7 +890,6 @@ static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned tomoyo_profile_ptr[profile] = ptr; ok: mutex_unlock(&lock); - /***** EXCLUSIVE SECTION END *****/ return ptr; } @@ -1009,7 +1018,19 @@ static int tomoyo_read_profile(struct tomoyo_io_buffer *head) return 0; } -/* Structure for policy manager. */ +/* + * tomoyo_policy_manager_entry is a structure which is used for holding list of + * domainnames or programs which are permitted to modify configuration via + * /sys/kernel/security/tomoyo/ interface. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_policy_manager_list . + * (2) "manager" is a domainname or a program's pathname. + * (3) "is_domain" is a bool which is true if "manager" is a domainname, false + * otherwise. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_policy_manager_entry { struct list_head list; /* A path to program or a domainname. */ @@ -1018,7 +1039,36 @@ struct tomoyo_policy_manager_entry { bool is_deleted; /* True if this entry is deleted. */ }; -/* The list for "struct tomoyo_policy_manager_entry". */ +/* + * tomoyo_policy_manager_list is used for holding list of domainnames or + * programs which are permitted to modify configuration via + * /sys/kernel/security/tomoyo/ interface. + * + * An entry is added by + * + * # echo '<kernel> /sbin/mingetty /bin/login /bin/bash' > \ + * /sys/kernel/security/tomoyo/manager + * (if you want to specify by a domainname) + * + * or + * + * # echo '/usr/lib/ccs/editpolicy' > /sys/kernel/security/tomoyo/manager + * (if you want to specify by a program's location) + * + * and is deleted by + * + * # echo 'delete <kernel> /sbin/mingetty /bin/login /bin/bash' > \ + * /sys/kernel/security/tomoyo/manager + * + * or + * + * # echo 'delete /usr/lib/ccs/editpolicy' > \ + * /sys/kernel/security/tomoyo/manager + * + * and all entries are retrieved by + * + * # cat /sys/kernel/security/tomoyo/manager + */ static LIST_HEAD(tomoyo_policy_manager_list); static DECLARE_RWSEM(tomoyo_policy_manager_list_lock); @@ -1050,7 +1100,6 @@ static int tomoyo_update_manager_entry(const char *manager, saved_manager = tomoyo_save_name(manager); if (!saved_manager) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_policy_manager_list_lock); list_for_each_entry(ptr, &tomoyo_policy_manager_list, list) { if (ptr->manager != saved_manager) @@ -1072,7 +1121,6 @@ static int tomoyo_update_manager_entry(const char *manager, error = 0; out: up_write(&tomoyo_policy_manager_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -1117,10 +1165,9 @@ static int tomoyo_read_manager_policy(struct tomoyo_io_buffer *head) list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, "%s\n", ptr->manager->name)) { - done = false; + done = tomoyo_io_printf(head, "%s\n", ptr->manager->name); + if (!done) break; - } } up_read(&tomoyo_policy_manager_list_lock); head->read_eof = done; @@ -1197,13 +1244,11 @@ static bool tomoyo_is_select_one(struct tomoyo_io_buffer *head, if (sscanf(data, "pid=%u", &pid) == 1) { struct task_struct *p; - /***** CRITICAL SECTION START *****/ read_lock(&tasklist_lock); p = find_task_by_vpid(pid); if (p) domain = tomoyo_real_domain(p); read_unlock(&tasklist_lock); - /***** CRITICAL SECTION END *****/ } else if (!strncmp(data, "domain=", 7)) { if (tomoyo_is_domain_def(data + 7)) { down_read(&tomoyo_domain_list_lock); @@ -1447,15 +1492,14 @@ static int tomoyo_read_domain_policy(struct tomoyo_io_buffer *head) TOMOYO_DOMAIN_FLAGS_IGNORE_GLOBAL_ALLOW_READ) ignore_global_allow_read = TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n"; - if (!tomoyo_io_printf(head, - "%s\n" TOMOYO_KEYWORD_USE_PROFILE "%u\n" - "%s%s%s\n", domain->domainname->name, - domain->profile, quota_exceeded, - transition_failed, - ignore_global_allow_read)) { - done = false; + done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE + "%u\n%s%s%s\n", + domain->domainname->name, + domain->profile, quota_exceeded, + transition_failed, + ignore_global_allow_read); + if (!done) break; - } head->read_step = 2; acl_loop: if (head->read_step == 3) @@ -1463,24 +1507,22 @@ acl_loop: /* Print ACL entries in the domain. */ down_read(&tomoyo_domain_acl_info_list_lock); list_for_each_cookie(apos, head->read_var2, - &domain->acl_info_list) { + &domain->acl_info_list) { struct tomoyo_acl_info *ptr = list_entry(apos, struct tomoyo_acl_info, - list); - if (!tomoyo_print_entry(head, ptr)) { - done = false; + list); + done = tomoyo_print_entry(head, ptr); + if (!done) break; - } } up_read(&tomoyo_domain_acl_info_list_lock); if (!done) break; head->read_step = 3; tail_mark: - if (!tomoyo_io_printf(head, "\n")) { - done = false; + done = tomoyo_io_printf(head, "\n"); + if (!done) break; - } head->read_step = 1; if (head->read_single_domain) break; @@ -1550,11 +1592,10 @@ static int tomoyo_read_domain_profile(struct tomoyo_io_buffer *head) domain = list_entry(pos, struct tomoyo_domain_info, list); if (domain->is_deleted) continue; - if (!tomoyo_io_printf(head, "%u %s\n", domain->profile, - domain->domainname->name)) { - done = false; + done = tomoyo_io_printf(head, "%u %s\n", domain->profile, + domain->domainname->name); + if (!done) break; - } } up_read(&tomoyo_domain_list_lock); head->read_eof = done; @@ -1594,13 +1635,11 @@ static int tomoyo_read_pid(struct tomoyo_io_buffer *head) const int pid = head->read_step; struct task_struct *p; struct tomoyo_domain_info *domain = NULL; - /***** CRITICAL SECTION START *****/ read_lock(&tasklist_lock); p = find_task_by_vpid(pid); if (p) domain = tomoyo_real_domain(p); read_unlock(&tasklist_lock); - /***** CRITICAL SECTION END *****/ if (domain) tomoyo_io_printf(head, "%d %u %s", pid, domain->profile, domain->domainname->name); @@ -2138,7 +2177,13 @@ static ssize_t tomoyo_write(struct file *file, const char __user *buf, return tomoyo_write_control(file, buf, count); } -/* Operations for /sys/kernel/security/tomoyo/ interface. */ +/* + * tomoyo_operations is a "struct file_operations" which is used for handling + * /sys/kernel/security/tomoyo/ interface. + * + * Some files under /sys/kernel/security/tomoyo/ directory accept open(O_RDWR). + * See tomoyo_io_buffer for internals. + */ static const struct file_operations tomoyo_operations = { .open = tomoyo_open, .release = tomoyo_release, diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h index 678f4ff16aa..6d6ba09af45 100644 --- a/security/tomoyo/common.h +++ b/security/tomoyo/common.h @@ -26,16 +26,43 @@ struct dentry; struct vfsmount; -/* Temporary buffer for holding pathnames. */ +/* + * tomoyo_page_buffer is a structure which is used for holding a pathname + * obtained from "struct dentry" and "struct vfsmount" pair. + * As of now, it is 4096 bytes. If users complain that 4096 bytes is too small + * (because TOMOYO escapes non ASCII printable characters using \ooo format), + * we will make the buffer larger. + */ struct tomoyo_page_buffer { char buffer[4096]; }; -/* Structure for holding a token. */ +/* + * tomoyo_path_info is a structure which is used for holding a string data + * used by TOMOYO. + * This structure has several fields for supporting pattern matching. + * + * (1) "name" is the '\0' terminated string data. + * (2) "hash" is full_name_hash(name, strlen(name)). + * This allows tomoyo_pathcmp() to compare by hash before actually compare + * using strcmp(). + * (3) "const_len" is the length of the initial segment of "name" which + * consists entirely of non wildcard characters. In other words, the length + * which we can compare two strings using strncmp(). + * (4) "is_dir" is a bool which is true if "name" ends with "/", + * false otherwise. + * TOMOYO distinguishes directory and non-directory. A directory ends with + * "/" and non-directory does not end with "/". + * (5) "is_patterned" is a bool which is true if "name" contains wildcard + * characters, false otherwise. This allows TOMOYO to use "hash" and + * strcmp() for string comparison if "is_patterned" is false. + * (6) "depth" is calculated using the number of "/" characters in "name". + * This allows TOMOYO to avoid comparing two pathnames which never match + * (e.g. whether "/var/www/html/index.html" matches "/tmp/sh-thd-\$"). + */ struct tomoyo_path_info { const char *name; u32 hash; /* = full_name_hash(name, strlen(name)) */ - u16 total_len; /* = strlen(name) */ u16 const_len; /* = tomoyo_const_part_length(name) */ bool is_dir; /* = tomoyo_strendswith(name, "/") */ bool is_patterned; /* = tomoyo_path_contains_pattern(name) */ @@ -51,7 +78,20 @@ struct tomoyo_path_info { */ #define TOMOYO_MAX_PATHNAME_LEN 4000 -/* Structure for holding requested pathname. */ +/* + * tomoyo_path_info_with_data is a structure which is used for holding a + * pathname obtained from "struct dentry" and "struct vfsmount" pair. + * + * "struct tomoyo_path_info_with_data" consists of "struct tomoyo_path_info" + * and buffer for the pathname, while "struct tomoyo_page_buffer" consists of + * buffer for the pathname only. + * + * "struct tomoyo_path_info_with_data" is intended to allow TOMOYO to release + * both "struct tomoyo_path_info" and buffer for the pathname by single kfree() + * so that we don't need to return two pointers to the caller. If the caller + * puts "struct tomoyo_path_info" on stack memory, we will be able to remove + * "struct tomoyo_path_info_with_data". + */ struct tomoyo_path_info_with_data { /* Keep "head" first, for this pointer is passed to tomoyo_free(). */ struct tomoyo_path_info head; @@ -61,7 +101,15 @@ struct tomoyo_path_info_with_data { }; /* - * Common header for holding ACL entries. + * tomoyo_acl_info is a structure which is used for holding + * + * (1) "list" which is linked to the ->acl_info_list of + * "struct tomoyo_domain_info" + * (2) "type" which tells + * (a) type & 0x7F : type of the entry (either + * "struct tomoyo_single_path_acl_record" or + * "struct tomoyo_double_path_acl_record") + * (b) type & 0x80 : whether the entry is marked as "deleted". * * Packing "struct tomoyo_acl_info" allows * "struct tomoyo_single_path_acl_record" to embed "u16" and @@ -81,7 +129,28 @@ struct tomoyo_acl_info { /* This ACL entry is deleted. */ #define TOMOYO_ACL_DELETED 0x80 -/* Structure for domain information. */ +/* + * tomoyo_domain_info is a structure which is used for holding permissions + * (e.g. "allow_read /lib/libc-2.5.so") given to each domain. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_domain_list . + * (2) "acl_info_list" which is linked to "struct tomoyo_acl_info". + * (3) "domainname" which holds the name of the domain. + * (4) "profile" which remembers profile number assigned to this domain. + * (5) "is_deleted" is a bool which is true if this domain is marked as + * "deleted", false otherwise. + * (6) "quota_warned" is a bool which is used for suppressing warning message + * when learning mode learned too much entries. + * (7) "flags" which remembers this domain's attributes. + * + * A domain's lifecycle is an analogy of files on / directory. + * Multiple domains with the same domainname cannot be created (as with + * creating files with the same filename fails with -EEXIST). + * If a process reached a domain, that process can reside in that domain after + * that domain is marked as "deleted" (as with a process can access an already + * open()ed file after that file was unlink()ed). + */ struct tomoyo_domain_info { struct list_head list; struct list_head acl_info_list; @@ -108,10 +177,18 @@ struct tomoyo_domain_info { #define TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED 2 /* - * Structure for "allow_read/write", "allow_execute", "allow_read", - * "allow_write", "allow_create", "allow_unlink", "allow_mkdir", "allow_rmdir", - * "allow_mkfifo", "allow_mksock", "allow_mkblock", "allow_mkchar", - * "allow_truncate", "allow_symlink" and "allow_rewrite" directive. + * tomoyo_single_path_acl_record is a structure which is used for holding an + * entry with one pathname operation (e.g. open(), mkdir()). + * It has following fields. + * + * (1) "head" which is a "struct tomoyo_acl_info". + * (2) "perm" which is a bitmask of permitted operations. + * (3) "filename" is the pathname. + * + * Directives held by this structure are "allow_read/write", "allow_execute", + * "allow_read", "allow_write", "allow_create", "allow_unlink", "allow_mkdir", + * "allow_rmdir", "allow_mkfifo", "allow_mksock", "allow_mkblock", + * "allow_mkchar", "allow_truncate", "allow_symlink" and "allow_rewrite". */ struct tomoyo_single_path_acl_record { struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_SINGLE_PATH_ACL */ @@ -120,7 +197,18 @@ struct tomoyo_single_path_acl_record { const struct tomoyo_path_info *filename; }; -/* Structure for "allow_rename" and "allow_link" directive. */ +/* + * tomoyo_double_path_acl_record is a structure which is used for holding an + * entry with two pathnames operation (i.e. link() and rename()). + * It has following fields. + * + * (1) "head" which is a "struct tomoyo_acl_info". + * (2) "perm" which is a bitmask of permitted operations. + * (3) "filename1" is the source/old pathname. + * (4) "filename2" is the destination/new pathname. + * + * Directives held by this structure are "allow_rename" and "allow_link". + */ struct tomoyo_double_path_acl_record { struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_DOUBLE_PATH_ACL */ u8 perm; @@ -153,7 +241,29 @@ struct tomoyo_double_path_acl_record { #define TOMOYO_VERBOSE 2 #define TOMOYO_MAX_CONTROL_INDEX 3 -/* Structure for reading/writing policy via securityfs interfaces. */ +/* + * tomoyo_io_buffer is a structure which is used for reading and modifying + * configuration via /sys/kernel/security/tomoyo/ interface. + * It has many fields. ->read_var1 , ->read_var2 , ->write_var1 are used as + * cursors. + * + * Since the content of /sys/kernel/security/tomoyo/domain_policy is a list of + * "struct tomoyo_domain_info" entries and each "struct tomoyo_domain_info" + * entry has a list of "struct tomoyo_acl_info", we need two cursors when + * reading (one is for traversing tomoyo_domain_list and the other is for + * traversing "struct tomoyo_acl_info"->acl_info_list ). + * + * If a line written to /sys/kernel/security/tomoyo/domain_policy starts with + * "select ", TOMOYO seeks the cursor ->read_var1 and ->write_var1 to the + * domain with the domainname specified by the rest of that line (NULL is set + * if seek failed). + * If a line written to /sys/kernel/security/tomoyo/domain_policy starts with + * "delete ", TOMOYO deletes an entry or a domain specified by the rest of that + * line (->write_var1 is set to NULL if a domain was deleted). + * If a line written to /sys/kernel/security/tomoyo/domain_policy starts with + * neither "select " nor "delete ", an entry or a domain specified by that line + * is appended. + */ struct tomoyo_io_buffer { int (*read) (struct tomoyo_io_buffer *); int (*write) (struct tomoyo_io_buffer *); diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c index 2d6748741a2..1d8b1696057 100644 --- a/security/tomoyo/domain.c +++ b/security/tomoyo/domain.c @@ -19,11 +19,63 @@ /* The initial domain. */ struct tomoyo_domain_info tomoyo_kernel_domain; -/* The list for "struct tomoyo_domain_info". */ +/* + * tomoyo_domain_list is used for holding list of domains. + * The ->acl_info_list of "struct tomoyo_domain_info" is used for holding + * permissions (e.g. "allow_read /lib/libc-2.5.so") given to each domain. + * + * An entry is added by + * + * # ( echo "<kernel>"; echo "allow_execute /sbin/init" ) > \ + * /sys/kernel/security/tomoyo/domain_policy + * + * and is deleted by + * + * # ( echo "<kernel>"; echo "delete allow_execute /sbin/init" ) > \ + * /sys/kernel/security/tomoyo/domain_policy + * + * and all entries are retrieved by + * + * # cat /sys/kernel/security/tomoyo/domain_policy + * + * A domain is added by + * + * # echo "<kernel>" > /sys/kernel/security/tomoyo/domain_policy + * + * and is deleted by + * + * # echo "delete <kernel>" > /sys/kernel/security/tomoyo/domain_policy + * + * and all domains are retrieved by + * + * # grep '^<kernel>' /sys/kernel/security/tomoyo/domain_policy + * + * Normally, a domainname is monotonically getting longer because a domainname + * which the process will belong to if an execve() operation succeeds is + * defined as a concatenation of "current domainname" + "pathname passed to + * execve()". + * See tomoyo_domain_initializer_list and tomoyo_domain_keeper_list for + * exceptions. + */ LIST_HEAD(tomoyo_domain_list); DECLARE_RWSEM(tomoyo_domain_list_lock); -/* Structure for "initialize_domain" and "no_initialize_domain" keyword. */ +/* + * tomoyo_domain_initializer_entry is a structure which is used for holding + * "initialize_domain" and "no_initialize_domain" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_domain_initializer_list . + * (2) "domainname" which is "a domainname" or "the last component of a + * domainname". This field is NULL if "from" clause is not specified. + * (3) "program" which is a program's pathname. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + * (5) "is_not" is a bool which is true if "no_initialize_domain", false + * otherwise. + * (6) "is_last_name" is a bool which is true if "domainname" is "the last + * component of a domainname", false otherwise. + */ struct tomoyo_domain_initializer_entry { struct list_head list; const struct tomoyo_path_info *domainname; /* This may be NULL */ @@ -34,7 +86,23 @@ struct tomoyo_domain_initializer_entry { bool is_last_name; }; -/* Structure for "keep_domain" and "no_keep_domain" keyword. */ +/* + * tomoyo_domain_keeper_entry is a structure which is used for holding + * "keep_domain" and "no_keep_domain" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_domain_keeper_list . + * (2) "domainname" which is "a domainname" or "the last component of a + * domainname". + * (3) "program" which is a program's pathname. + * This field is NULL if "from" clause is not specified. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + * (5) "is_not" is a bool which is true if "no_initialize_domain", false + * otherwise. + * (6) "is_last_name" is a bool which is true if "domainname" is "the last + * component of a domainname", false otherwise. + */ struct tomoyo_domain_keeper_entry { struct list_head list; const struct tomoyo_path_info *domainname; @@ -45,7 +113,16 @@ struct tomoyo_domain_keeper_entry { bool is_last_name; }; -/* Structure for "alias" keyword. */ +/* + * tomoyo_alias_entry is a structure which is used for holding "alias" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_alias_list . + * (2) "original_name" which is a dereferenced pathname. + * (3) "aliased_name" which is a symlink's pathname. + * (4) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_alias_entry { struct list_head list; const struct tomoyo_path_info *original_name; @@ -67,14 +144,12 @@ void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain, { /* We need to serialize because this is bitfield operation. */ static DEFINE_SPINLOCK(lock); - /***** CRITICAL SECTION START *****/ spin_lock(&lock); if (!is_delete) domain->flags |= flags; else domain->flags &= ~flags; spin_unlock(&lock); - /***** CRITICAL SECTION END *****/ } /** @@ -94,7 +169,42 @@ const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain) return cp0; } -/* The list for "struct tomoyo_domain_initializer_entry". */ +/* + * tomoyo_domain_initializer_list is used for holding list of programs which + * triggers reinitialization of domainname. Normally, a domainname is + * monotonically getting longer. But sometimes, we restart daemon programs. + * It would be convenient for us that "a daemon started upon system boot" and + * "the daemon restarted from console" belong to the same domain. Thus, TOMOYO + * provides a way to shorten domainnames. + * + * An entry is added by + * + * # echo 'initialize_domain /usr/sbin/httpd' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete initialize_domain /usr/sbin/httpd' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^initialize_domain /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, /usr/sbin/httpd will belong to + * "<kernel> /usr/sbin/httpd" domain. + * + * You may specify a domainname using "from" keyword. + * "initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" + * will cause "/usr/sbin/httpd" executed from "<kernel> /etc/rc.d/init.d/httpd" + * domain to belong to "<kernel> /usr/sbin/httpd" domain. + * + * You may add "no_" prefix to "initialize_domain". + * "initialize_domain /usr/sbin/httpd" and + * "no_initialize_domain /usr/sbin/httpd from <kernel> /etc/rc.d/init.d/httpd" + * will cause "/usr/sbin/httpd" to belong to "<kernel> /usr/sbin/httpd" domain + * unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain. + */ static LIST_HEAD(tomoyo_domain_initializer_list); static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock); @@ -135,7 +245,6 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname, saved_program = tomoyo_save_name(program); if (!saved_program) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_initializer_list_lock); list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) { if (ptr->is_not != is_not || @@ -161,7 +270,6 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname, error = 0; out: up_write(&tomoyo_domain_initializer_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -193,13 +301,12 @@ bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head) from = " from "; domain = ptr->domainname->name; } - if (!tomoyo_io_printf(head, - "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN - "%s%s%s\n", no, ptr->program->name, from, - domain)) { - done = false; + done = tomoyo_io_printf(head, + "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN + "%s%s%s\n", no, ptr->program->name, + from, domain); + if (!done) break; - } } up_read(&tomoyo_domain_initializer_list_lock); return done; @@ -273,7 +380,44 @@ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info * return flag; } -/* The list for "struct tomoyo_domain_keeper_entry". */ +/* + * tomoyo_domain_keeper_list is used for holding list of domainnames which + * suppresses domain transition. Normally, a domainname is monotonically + * getting longer. But sometimes, we want to suppress domain transition. + * It would be convenient for us that programs executed from a login session + * belong to the same domain. Thus, TOMOYO provides a way to suppress domain + * transition. + * + * An entry is added by + * + * # echo 'keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete keep_domain <kernel> /usr/sbin/sshd /bin/bash' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^keep_domain /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, any process which belongs to + * "<kernel> /usr/sbin/sshd /bin/bash" domain will remain in that domain, + * unless explicitly specified by "initialize_domain" or "no_keep_domain". + * + * You may specify a program using "from" keyword. + * "keep_domain /bin/pwd from <kernel> /usr/sbin/sshd /bin/bash" + * will cause "/bin/pwd" executed from "<kernel> /usr/sbin/sshd /bin/bash" + * domain to remain in "<kernel> /usr/sbin/sshd /bin/bash" domain. + * + * You may add "no_" prefix to "keep_domain". + * "keep_domain <kernel> /usr/sbin/sshd /bin/bash" and + * "no_keep_domain /usr/bin/passwd from <kernel> /usr/sbin/sshd /bin/bash" will + * cause "/usr/bin/passwd" to belong to + * "<kernel> /usr/sbin/sshd /bin/bash /usr/bin/passwd" domain, unless + * explicitly specified by "initialize_domain". + */ static LIST_HEAD(tomoyo_domain_keeper_list); static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock); @@ -296,7 +440,6 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname, struct tomoyo_domain_keeper_entry *ptr; const struct tomoyo_path_info *saved_domainname; const struct tomoyo_path_info *saved_program = NULL; - static DEFINE_MUTEX(lock); int error = -ENOMEM; bool is_last_name = false; @@ -315,7 +458,6 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname, saved_domainname = tomoyo_save_name(domainname); if (!saved_domainname) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_keeper_list_lock); list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) { if (ptr->is_not != is_not || @@ -341,7 +483,6 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname, error = 0; out: up_write(&tomoyo_domain_keeper_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -394,13 +535,12 @@ bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head) from = " from "; program = ptr->program->name; } - if (!tomoyo_io_printf(head, - "%s" TOMOYO_KEYWORD_KEEP_DOMAIN - "%s%s%s\n", no, program, from, - ptr->domainname->name)) { - done = false; + done = tomoyo_io_printf(head, + "%s" TOMOYO_KEYWORD_KEEP_DOMAIN + "%s%s%s\n", no, program, from, + ptr->domainname->name); + if (!done) break; - } } up_read(&tomoyo_domain_keeper_list_lock); return done; @@ -446,7 +586,36 @@ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname, return flag; } -/* The list for "struct tomoyo_alias_entry". */ +/* + * tomoyo_alias_list is used for holding list of symlink's pathnames which are + * allowed to be passed to an execve() request. Normally, the domainname which + * the current process will belong to after execve() succeeds is calculated + * using dereferenced pathnames. But some programs behave differently depending + * on the name passed to argv[0]. For busybox, calculating domainname using + * dereferenced pathnames will cause all programs in the busybox to belong to + * the same domain. Thus, TOMOYO provides a way to allow use of symlink's + * pathname for checking execve()'s permission and calculating domainname which + * the current process will belong to after execve() succeeds. + * + * An entry is added by + * + * # echo 'alias /bin/busybox /bin/cat' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete alias /bin/busybox /bin/cat' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^alias /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, if /bin/cat is a symlink to /bin/busybox and execution + * of /bin/cat is requested, permission is checked for /bin/cat rather than + * /bin/busybox and domainname which the current process will belong to after + * execve() succeeds is calculated using /bin/cat rather than /bin/busybox . + */ static LIST_HEAD(tomoyo_alias_list); static DECLARE_RWSEM(tomoyo_alias_list_lock); @@ -476,7 +645,6 @@ static int tomoyo_update_alias_entry(const char *original_name, saved_aliased_name = tomoyo_save_name(aliased_name); if (!saved_original_name || !saved_aliased_name) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_alias_list_lock); list_for_each_entry(ptr, &tomoyo_alias_list, list) { if (ptr->original_name != saved_original_name || @@ -499,7 +667,6 @@ static int tomoyo_update_alias_entry(const char *original_name, error = 0; out: up_write(&tomoyo_alias_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -522,12 +689,11 @@ bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head) ptr = list_entry(pos, struct tomoyo_alias_entry, list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", - ptr->original_name->name, - ptr->aliased_name->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", + ptr->original_name->name, + ptr->aliased_name->name); + if (!done) break; - } } up_read(&tomoyo_alias_list_lock); return done; @@ -567,7 +733,6 @@ int tomoyo_delete_domain(char *domainname) name.name = domainname; tomoyo_fill_path_info(&name); - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_list_lock); /* Is there an active domain? */ list_for_each_entry(domain, &tomoyo_domain_list, list) { @@ -581,7 +746,6 @@ int tomoyo_delete_domain(char *domainname) break; } up_write(&tomoyo_domain_list_lock); - /***** EXCLUSIVE SECTION END *****/ return 0; } @@ -600,7 +764,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * struct tomoyo_domain_info *domain = NULL; const struct tomoyo_path_info *saved_domainname; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_list_lock); domain = tomoyo_find_domain(domainname); if (domain) @@ -619,7 +782,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * domain->domainname != saved_domainname) continue; flag = false; - /***** CRITICAL SECTION START *****/ read_lock(&tasklist_lock); for_each_process(p) { if (tomoyo_real_domain(p) != domain) @@ -628,7 +790,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * break; } read_unlock(&tasklist_lock); - /***** CRITICAL SECTION END *****/ if (flag) continue; list_for_each_entry(ptr, &domain->acl_info_list, list) { @@ -651,7 +812,6 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * } out: up_write(&tomoyo_domain_list_lock); - /***** EXCLUSIVE SECTION END *****/ return domain; } @@ -739,7 +899,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm, } /* Check execute permission. */ - retval = tomoyo_check_exec_perm(old_domain, &r, tmp); + retval = tomoyo_check_exec_perm(old_domain, &r); if (retval < 0) goto out; diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c index 2316da8ec5b..5ae3a571559 100644 --- a/security/tomoyo/file.c +++ b/security/tomoyo/file.c @@ -14,21 +14,50 @@ #include "realpath.h" #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE]) -/* Structure for "allow_read" keyword. */ +/* + * tomoyo_globally_readable_file_entry is a structure which is used for holding + * "allow_read" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_globally_readable_list . + * (2) "filename" is a pathname which is allowed to open(O_RDONLY). + * (3) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_globally_readable_file_entry { struct list_head list; const struct tomoyo_path_info *filename; bool is_deleted; }; -/* Structure for "file_pattern" keyword. */ +/* + * tomoyo_pattern_entry is a structure which is used for holding + * "tomoyo_pattern_list" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_pattern_list . + * (2) "pattern" is a pathname pattern which is used for converting pathnames + * to pathname patterns during learning mode. + * (3) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_pattern_entry { struct list_head list; const struct tomoyo_path_info *pattern; bool is_deleted; }; -/* Structure for "deny_rewrite" keyword. */ +/* + * tomoyo_no_rewrite_entry is a structure which is used for holding + * "deny_rewrite" entries. + * It has following fields. + * + * (1) "list" which is linked to tomoyo_no_rewrite_list . + * (2) "pattern" is a pathname which is by default not permitted to modify + * already existing content. + * (3) "is_deleted" is a bool which is true if marked as deleted, false + * otherwise. + */ struct tomoyo_no_rewrite_entry { struct list_head list; const struct tomoyo_path_info *pattern; @@ -141,7 +170,31 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, struct tomoyo_domain_info * const domain, const bool is_delete); -/* The list for "struct tomoyo_globally_readable_file_entry". */ +/* + * tomoyo_globally_readable_list is used for holding list of pathnames which + * are by default allowed to be open()ed for reading by any process. + * + * An entry is added by + * + * # echo 'allow_read /lib/libc-2.5.so' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete allow_read /lib/libc-2.5.so' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^allow_read /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, any process is allowed to + * open("/lib/libc-2.5.so", O_RDONLY). + * One exception is, if the domain which current process belongs to is marked + * as "ignore_global_allow_read", current process can't do so unless explicitly + * given "allow_read /lib/libc-2.5.so" to the domain which current process + * belongs to. + */ static LIST_HEAD(tomoyo_globally_readable_list); static DECLARE_RWSEM(tomoyo_globally_readable_list_lock); @@ -166,7 +219,6 @@ static int tomoyo_update_globally_readable_entry(const char *filename, saved_filename = tomoyo_save_name(filename); if (!saved_filename) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_globally_readable_list_lock); list_for_each_entry(ptr, &tomoyo_globally_readable_list, list) { if (ptr->filename != saved_filename) @@ -187,7 +239,6 @@ static int tomoyo_update_globally_readable_entry(const char *filename, error = 0; out: up_write(&tomoyo_globally_readable_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -249,17 +300,44 @@ bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head) list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n", - ptr->filename->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_READ "%s\n", + ptr->filename->name); + if (!done) break; - } } up_read(&tomoyo_globally_readable_list_lock); return done; } -/* The list for "struct tomoyo_pattern_entry". */ +/* tomoyo_pattern_list is used for holding list of pathnames which are used for + * converting pathnames to pathname patterns during learning mode. + * + * An entry is added by + * + * # echo 'file_pattern /proc/\$/mounts' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete file_pattern /proc/\$/mounts' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^file_pattern /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, if a process which belongs to a domain which is in + * learning mode requested open("/proc/1/mounts", O_RDONLY), + * "allow_read /proc/\$/mounts" is automatically added to the domain which that + * process belongs to. + * + * It is not a desirable behavior that we have to use /proc/\$/ instead of + * /proc/self/ when current process needs to access only current process's + * information. As of now, LSM version of TOMOYO is using __d_path() for + * calculating pathname. Non LSM version of TOMOYO is using its own function + * which pretends as if /proc/self/ is not a symlink; so that we can forbid + * current process from accessing other process's information. + */ static LIST_HEAD(tomoyo_pattern_list); static DECLARE_RWSEM(tomoyo_pattern_list_lock); @@ -284,7 +362,6 @@ static int tomoyo_update_file_pattern_entry(const char *pattern, saved_pattern = tomoyo_save_name(pattern); if (!saved_pattern) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_pattern_list_lock); list_for_each_entry(ptr, &tomoyo_pattern_list, list) { if (saved_pattern != ptr->pattern) @@ -305,7 +382,6 @@ static int tomoyo_update_file_pattern_entry(const char *pattern, error = 0; out: up_write(&tomoyo_pattern_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -373,17 +449,44 @@ bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head) ptr = list_entry(pos, struct tomoyo_pattern_entry, list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN "%s\n", - ptr->pattern->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_FILE_PATTERN + "%s\n", ptr->pattern->name); + if (!done) break; - } } up_read(&tomoyo_pattern_list_lock); return done; } -/* The list for "struct tomoyo_no_rewrite_entry". */ +/* + * tomoyo_no_rewrite_list is used for holding list of pathnames which are by + * default forbidden to modify already written content of a file. + * + * An entry is added by + * + * # echo 'deny_rewrite /var/log/messages' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and is deleted by + * + * # echo 'delete deny_rewrite /var/log/messages' > \ + * /sys/kernel/security/tomoyo/exception_policy + * + * and all entries are retrieved by + * + * # grep ^deny_rewrite /sys/kernel/security/tomoyo/exception_policy + * + * In the example above, if a process requested to rewrite /var/log/messages , + * the process can't rewrite unless the domain which that process belongs to + * has "allow_rewrite /var/log/messages" entry. + * + * It is not a desirable behavior that we have to add "\040(deleted)" suffix + * when we want to allow rewriting already unlink()ed file. As of now, + * LSM version of TOMOYO is using __d_path() for calculating pathname. + * Non LSM version of TOMOYO is using its own function which doesn't append + * " (deleted)" suffix if the file is already unlink()ed; so that we don't + * need to worry whether the file is already unlink()ed or not. + */ static LIST_HEAD(tomoyo_no_rewrite_list); static DECLARE_RWSEM(tomoyo_no_rewrite_list_lock); @@ -407,7 +510,6 @@ static int tomoyo_update_no_rewrite_entry(const char *pattern, saved_pattern = tomoyo_save_name(pattern); if (!saved_pattern) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_no_rewrite_list_lock); list_for_each_entry(ptr, &tomoyo_no_rewrite_list, list) { if (ptr->pattern != saved_pattern) @@ -428,7 +530,6 @@ static int tomoyo_update_no_rewrite_entry(const char *pattern, error = 0; out: up_write(&tomoyo_no_rewrite_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -489,11 +590,10 @@ bool tomoyo_read_no_rewrite_policy(struct tomoyo_io_buffer *head) ptr = list_entry(pos, struct tomoyo_no_rewrite_entry, list); if (ptr->is_deleted) continue; - if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE "%s\n", - ptr->pattern->name)) { - done = false; + done = tomoyo_io_printf(head, TOMOYO_KEYWORD_DENY_REWRITE + "%s\n", ptr->pattern->name); + if (!done) break; - } } up_read(&tomoyo_no_rewrite_list_lock); return done; @@ -745,7 +845,6 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, saved_filename = tomoyo_save_name(filename); if (!saved_filename) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_acl_info_list_lock); if (is_delete) goto delete; @@ -800,7 +899,6 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename, } out: up_write(&tomoyo_domain_acl_info_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -836,7 +934,6 @@ static int tomoyo_update_double_path_acl(const u8 type, const char *filename1, saved_filename2 = tomoyo_save_name(filename2); if (!saved_filename1 || !saved_filename2) return -ENOMEM; - /***** EXCLUSIVE SECTION START *****/ down_write(&tomoyo_domain_acl_info_list_lock); if (is_delete) goto delete; @@ -884,7 +981,6 @@ static int tomoyo_update_double_path_acl(const u8 type, const char *filename1, } out: up_write(&tomoyo_domain_acl_info_list_lock); - /***** EXCLUSIVE SECTION END *****/ return error; } @@ -1025,13 +1121,11 @@ int tomoyo_check_file_perm(struct tomoyo_domain_info *domain, * * @domain: Pointer to "struct tomoyo_domain_info". * @filename: Check permission for "execute". - * @tmp: Buffer for temporary use. * * Returns 0 on success, negativevalue otherwise. */ int tomoyo_check_exec_perm(struct tomoyo_domain_info *domain, - const struct tomoyo_path_info *filename, - struct tomoyo_page_buffer *tmp) + const struct tomoyo_path_info *filename) { const u8 mode = tomoyo_check_flags(domain, TOMOYO_MAC_FOR_FILE); diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c index 40927a84cb6..5f2e3326337 100644 --- a/security/tomoyo/realpath.c +++ b/security/tomoyo/realpath.c @@ -220,7 +220,6 @@ void *tomoyo_alloc_element(const unsigned int size) = roundup(size, max(sizeof(void *), sizeof(long))); if (word_aligned_size > PATH_MAX) return NULL; - /***** EXCLUSIVE SECTION START *****/ mutex_lock(&lock); if (buf_used_len + word_aligned_size > PATH_MAX) { if (!tomoyo_quota_for_elements || @@ -251,7 +250,6 @@ void *tomoyo_alloc_element(const unsigned int size) } } mutex_unlock(&lock); - /***** EXCLUSIVE SECTION END *****/ return ptr; } @@ -267,7 +265,16 @@ static unsigned int tomoyo_quota_for_savename; */ #define TOMOYO_MAX_HASH 256 -/* Structure for string data. */ +/* + * tomoyo_name_entry is a structure which is used for linking + * "struct tomoyo_path_info" into tomoyo_name_list . + * + * Since tomoyo_name_list manages a list of strings which are shared by + * multiple processes (whereas "struct tomoyo_path_info" inside + * "struct tomoyo_path_info_with_data" is not shared), a reference counter will + * be added to "struct tomoyo_name_entry" rather than "struct tomoyo_path_info" + * when TOMOYO starts supporting garbage collector. + */ struct tomoyo_name_entry { struct list_head list; struct tomoyo_path_info entry; @@ -281,10 +288,10 @@ struct tomoyo_free_memory_block_list { }; /* - * The list for "struct tomoyo_name_entry". - * - * This list is updated only inside tomoyo_save_name(), thus - * no global mutex exists. + * tomoyo_name_list is used for holding string data used by TOMOYO. + * Since same string data is likely used for multiple times (e.g. + * "/lib/libc-2.5.so"), TOMOYO shares string data in the form of + * "const struct tomoyo_path_info *". */ static struct list_head tomoyo_name_list[TOMOYO_MAX_HASH]; @@ -318,7 +325,6 @@ const struct tomoyo_path_info *tomoyo_save_name(const char *name) return NULL; } hash = full_name_hash((const unsigned char *) name, len - 1); - /***** EXCLUSIVE SECTION START *****/ mutex_lock(&lock); list_for_each_entry(ptr, &tomoyo_name_list[hash % TOMOYO_MAX_HASH], list) { @@ -366,7 +372,6 @@ const struct tomoyo_path_info *tomoyo_save_name(const char *name) } out: mutex_unlock(&lock); - /***** EXCLUSIVE SECTION END *****/ return ptr ? &ptr->entry : NULL; } diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c index e42be5c4f05..3194d09fe0f 100644 --- a/security/tomoyo/tomoyo.c +++ b/security/tomoyo/tomoyo.c @@ -262,6 +262,10 @@ static int tomoyo_dentry_open(struct file *f, const struct cred *cred) return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags); } +/* + * tomoyo_security_ops is a "struct security_operations" which is used for + * registering TOMOYO. + */ static struct security_operations tomoyo_security_ops = { .name = "tomoyo", .cred_prepare = tomoyo_cred_prepare, diff --git a/security/tomoyo/tomoyo.h b/security/tomoyo/tomoyo.h index 41c6ebafb9c..0fd588a629c 100644 --- a/security/tomoyo/tomoyo.h +++ b/security/tomoyo/tomoyo.h @@ -17,13 +17,11 @@ struct path; struct inode; struct linux_binprm; struct pt_regs; -struct tomoyo_page_buffer; int tomoyo_check_file_perm(struct tomoyo_domain_info *domain, const char *filename, const u8 perm); int tomoyo_check_exec_perm(struct tomoyo_domain_info *domain, - const struct tomoyo_path_info *filename, - struct tomoyo_page_buffer *buf); + const struct tomoyo_path_info *filename); int tomoyo_check_open_permission(struct tomoyo_domain_info *domain, struct path *path, const int flag); int tomoyo_check_1path_perm(struct tomoyo_domain_info *domain, @@ -90,17 +88,10 @@ static inline struct tomoyo_domain_info *tomoyo_domain(void) return current_cred()->security; } -/* Caller holds tasklist_lock spinlock. */ static inline struct tomoyo_domain_info *tomoyo_real_domain(struct task_struct *task) { - /***** CRITICAL SECTION START *****/ - const struct cred *cred = get_task_cred(task); - struct tomoyo_domain_info *domain = cred->security; - - put_cred(cred); - return domain; - /***** CRITICAL SECTION END *****/ + return task_cred_xxx(task, security); } #endif /* !defined(_SECURITY_TOMOYO_TOMOYO_H) */ |