| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Security plug functions |
| * |
| * Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com> |
| * Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com> |
| * Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com> |
| * Copyright (C) 2016 Mellanox Technologies |
| * Copyright (C) 2023 Microsoft Corporation <paul@paul-moore.com> |
| */ |
| |
| #define pr_fmt(fmt) "LSM: " fmt |
| |
| #include <linux/bpf.h> |
| #include <linux/capability.h> |
| #include <linux/dcache.h> |
| #include <linux/export.h> |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/kernel_read_file.h> |
| #include <linux/lsm_hooks.h> |
| #include <linux/fsnotify.h> |
| #include <linux/mman.h> |
| #include <linux/mount.h> |
| #include <linux/personality.h> |
| #include <linux/backing-dev.h> |
| #include <linux/string.h> |
| #include <linux/xattr.h> |
| #include <linux/msg.h> |
| #include <linux/overflow.h> |
| #include <net/flow.h> |
| |
| /* How many LSMs were built into the kernel? */ |
| #define LSM_COUNT (__end_lsm_info - __start_lsm_info) |
| |
| /* |
| * How many LSMs are built into the kernel as determined at |
| * build time. Used to determine fixed array sizes. |
| * The capability module is accounted for by CONFIG_SECURITY |
| */ |
| #define LSM_CONFIG_COUNT ( \ |
| (IS_ENABLED(CONFIG_SECURITY) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_TOMOYO) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_YAMA) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_LOADPIN) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_SAFESETID) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_LOCKDOWN_LSM) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_BPF_LSM) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_SECURITY_LANDLOCK) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_IMA) ? 1 : 0) + \ |
| (IS_ENABLED(CONFIG_EVM) ? 1 : 0)) |
| |
| /* |
| * These are descriptions of the reasons that can be passed to the |
| * security_locked_down() LSM hook. Placing this array here allows |
| * all security modules to use the same descriptions for auditing |
| * purposes. |
| */ |
| const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX + 1] = { |
| [LOCKDOWN_NONE] = "none", |
| [LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading", |
| [LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port", |
| [LOCKDOWN_EFI_TEST] = "/dev/efi_test access", |
| [LOCKDOWN_KEXEC] = "kexec of unsigned images", |
| [LOCKDOWN_HIBERNATION] = "hibernation", |
| [LOCKDOWN_PCI_ACCESS] = "direct PCI access", |
| [LOCKDOWN_IOPORT] = "raw io port access", |
| [LOCKDOWN_MSR] = "raw MSR access", |
| [LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables", |
| [LOCKDOWN_DEVICE_TREE] = "modifying device tree contents", |
| [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage", |
| [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO", |
| [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters", |
| [LOCKDOWN_MMIOTRACE] = "unsafe mmio", |
| [LOCKDOWN_DEBUGFS] = "debugfs access", |
| [LOCKDOWN_XMON_WR] = "xmon write access", |
| [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", |
| [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", |
| [LOCKDOWN_RTAS_ERROR_INJECTION] = "RTAS error injection", |
| [LOCKDOWN_INTEGRITY_MAX] = "integrity", |
| [LOCKDOWN_KCORE] = "/proc/kcore access", |
| [LOCKDOWN_KPROBES] = "use of kprobes", |
| [LOCKDOWN_BPF_READ_KERNEL] = "use of bpf to read kernel RAM", |
| [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", |
| [LOCKDOWN_PERF] = "unsafe use of perf", |
| [LOCKDOWN_TRACEFS] = "use of tracefs", |
| [LOCKDOWN_XMON_RW] = "xmon read and write access", |
| [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", |
| [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", |
| }; |
| |
| struct security_hook_heads security_hook_heads __ro_after_init; |
| static BLOCKING_NOTIFIER_HEAD(blocking_lsm_notifier_chain); |
| |
| static struct kmem_cache *lsm_file_cache; |
| static struct kmem_cache *lsm_inode_cache; |
| |
| char *lsm_names; |
| static struct lsm_blob_sizes blob_sizes __ro_after_init; |
| |
| /* Boot-time LSM user choice */ |
| static __initdata const char *chosen_lsm_order; |
| static __initdata const char *chosen_major_lsm; |
| |
| static __initconst const char *const builtin_lsm_order = CONFIG_LSM; |
| |
| /* Ordered list of LSMs to initialize. */ |
| static __initdata struct lsm_info **ordered_lsms; |
| static __initdata struct lsm_info *exclusive; |
| |
| static __initdata bool debug; |
| #define init_debug(...) \ |
| do { \ |
| if (debug) \ |
| pr_info(__VA_ARGS__); \ |
| } while (0) |
| |
| static bool __init is_enabled(struct lsm_info *lsm) |
| { |
| if (!lsm->enabled) |
| return false; |
| |
| return *lsm->enabled; |
| } |
| |
| /* Mark an LSM's enabled flag. */ |
| static int lsm_enabled_true __initdata = 1; |
| static int lsm_enabled_false __initdata = 0; |
| static void __init set_enabled(struct lsm_info *lsm, bool enabled) |
| { |
| /* |
| * When an LSM hasn't configured an enable variable, we can use |
| * a hard-coded location for storing the default enabled state. |
| */ |
| if (!lsm->enabled) { |
| if (enabled) |
| lsm->enabled = &lsm_enabled_true; |
| else |
| lsm->enabled = &lsm_enabled_false; |
| } else if (lsm->enabled == &lsm_enabled_true) { |
| if (!enabled) |
| lsm->enabled = &lsm_enabled_false; |
| } else if (lsm->enabled == &lsm_enabled_false) { |
| if (enabled) |
| lsm->enabled = &lsm_enabled_true; |
| } else { |
| *lsm->enabled = enabled; |
| } |
| } |
| |
| /* Is an LSM already listed in the ordered LSMs list? */ |
| static bool __init exists_ordered_lsm(struct lsm_info *lsm) |
| { |
| struct lsm_info **check; |
| |
| for (check = ordered_lsms; *check; check++) |
| if (*check == lsm) |
| return true; |
| |
| return false; |
| } |
| |
| /* Append an LSM to the list of ordered LSMs to initialize. */ |
| static int last_lsm __initdata; |
| static void __init append_ordered_lsm(struct lsm_info *lsm, const char *from) |
| { |
| /* Ignore duplicate selections. */ |
| if (exists_ordered_lsm(lsm)) |
| return; |
| |
| if (WARN(last_lsm == LSM_COUNT, "%s: out of LSM slots!?\n", from)) |
| return; |
| |
| /* Enable this LSM, if it is not already set. */ |
| if (!lsm->enabled) |
| lsm->enabled = &lsm_enabled_true; |
| ordered_lsms[last_lsm++] = lsm; |
| |
| init_debug("%s ordered: %s (%s)\n", from, lsm->name, |
| is_enabled(lsm) ? "enabled" : "disabled"); |
| } |
| |
| /* Is an LSM allowed to be initialized? */ |
| static bool __init lsm_allowed(struct lsm_info *lsm) |
| { |
| /* Skip if the LSM is disabled. */ |
| if (!is_enabled(lsm)) |
| return false; |
| |
| /* Not allowed if another exclusive LSM already initialized. */ |
| if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && exclusive) { |
| init_debug("exclusive disabled: %s\n", lsm->name); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static void __init lsm_set_blob_size(int *need, int *lbs) |
| { |
| int offset; |
| |
| if (*need <= 0) |
| return; |
| |
| offset = ALIGN(*lbs, sizeof(void *)); |
| *lbs = offset + *need; |
| *need = offset; |
| } |
| |
| static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) |
| { |
| if (!needed) |
| return; |
| |
| lsm_set_blob_size(&needed->lbs_cred, &blob_sizes.lbs_cred); |
| lsm_set_blob_size(&needed->lbs_file, &blob_sizes.lbs_file); |
| /* |
| * The inode blob gets an rcu_head in addition to |
| * what the modules might need. |
| */ |
| if (needed->lbs_inode && blob_sizes.lbs_inode == 0) |
| blob_sizes.lbs_inode = sizeof(struct rcu_head); |
| lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode); |
| lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); |
| lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); |
| lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); |
| lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); |
| lsm_set_blob_size(&needed->lbs_xattr_count, |
| &blob_sizes.lbs_xattr_count); |
| } |
| |
| /* Prepare LSM for initialization. */ |
| static void __init prepare_lsm(struct lsm_info *lsm) |
| { |
| int enabled = lsm_allowed(lsm); |
| |
| /* Record enablement (to handle any following exclusive LSMs). */ |
| set_enabled(lsm, enabled); |
| |
| /* If enabled, do pre-initialization work. */ |
| if (enabled) { |
| if ((lsm->flags & LSM_FLAG_EXCLUSIVE) && !exclusive) { |
| exclusive = lsm; |
| init_debug("exclusive chosen: %s\n", lsm->name); |
| } |
| |
| lsm_set_blob_sizes(lsm->blobs); |
| } |
| } |
| |
| /* Initialize a given LSM, if it is enabled. */ |
| static void __init initialize_lsm(struct lsm_info *lsm) |
| { |
| if (is_enabled(lsm)) { |
| int ret; |
| |
| init_debug("initializing %s\n", lsm->name); |
| ret = lsm->init(); |
| WARN(ret, "%s failed to initialize: %d\n", lsm->name, ret); |
| } |
| } |
| |
| /* |
| * Current index to use while initializing the lsm id list. |
| */ |
| u32 lsm_active_cnt __ro_after_init; |
| const struct lsm_id *lsm_idlist[LSM_CONFIG_COUNT]; |
| |
| /* Populate ordered LSMs list from comma-separated LSM name list. */ |
| static void __init ordered_lsm_parse(const char *order, const char *origin) |
| { |
| struct lsm_info *lsm; |
| char *sep, *name, *next; |
| |
| /* LSM_ORDER_FIRST is always first. */ |
| for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { |
| if (lsm->order == LSM_ORDER_FIRST) |
| append_ordered_lsm(lsm, " first"); |
| } |
| |
| /* Process "security=", if given. */ |
| if (chosen_major_lsm) { |
| struct lsm_info *major; |
| |
| /* |
| * To match the original "security=" behavior, this |
| * explicitly does NOT fallback to another Legacy Major |
| * if the selected one was separately disabled: disable |
| * all non-matching Legacy Major LSMs. |
| */ |
| for (major = __start_lsm_info; major < __end_lsm_info; |
| major++) { |
| if ((major->flags & LSM_FLAG_LEGACY_MAJOR) && |
| strcmp(major->name, chosen_major_lsm) != 0) { |
| set_enabled(major, false); |
| init_debug("security=%s disabled: %s (only one legacy major LSM)\n", |
| chosen_major_lsm, major->name); |
| } |
| } |
| } |
| |
| sep = kstrdup(order, GFP_KERNEL); |
| next = sep; |
| /* Walk the list, looking for matching LSMs. */ |
| while ((name = strsep(&next, ",")) != NULL) { |
| bool found = false; |
| |
| for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { |
| if (strcmp(lsm->name, name) == 0) { |
| if (lsm->order == LSM_ORDER_MUTABLE) |
| append_ordered_lsm(lsm, origin); |
| found = true; |
| } |
| } |
| |
| if (!found) |
| init_debug("%s ignored: %s (not built into kernel)\n", |
| origin, name); |
| } |
| |
| /* Process "security=", if given. */ |
| if (chosen_major_lsm) { |
| for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { |
| if (exists_ordered_lsm(lsm)) |
| continue; |
| if (strcmp(lsm->name, chosen_major_lsm) == 0) |
| append_ordered_lsm(lsm, "security="); |
| } |
| } |
| |
| /* LSM_ORDER_LAST is always last. */ |
| for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { |
| if (lsm->order == LSM_ORDER_LAST) |
| append_ordered_lsm(lsm, " last"); |
| } |
| |
| /* Disable all LSMs not in the ordered list. */ |
| for (lsm = __start_lsm_info; lsm < __end_lsm_info; lsm++) { |
| if (exists_ordered_lsm(lsm)) |
| continue; |
| set_enabled(lsm, false); |
| init_debug("%s skipped: %s (not in requested order)\n", |
| origin, lsm->name); |
| } |
| |
| kfree(sep); |
| } |
| |
| static void __init lsm_early_cred(struct cred *cred); |
| static void __init lsm_early_task(struct task_struct *task); |
| |
| static int lsm_append(const char *new, char **result); |
| |
| static void __init report_lsm_order(void) |
| { |
| struct lsm_info **lsm, *early; |
| int first = 0; |
| |
| pr_info("initializing lsm="); |
| |
| /* Report each enabled LSM name, comma separated. */ |
| for (early = __start_early_lsm_info; |
| early < __end_early_lsm_info; early++) |
| if (is_enabled(early)) |
| pr_cont("%s%s", first++ == 0 ? "" : ",", early->name); |
| for (lsm = ordered_lsms; *lsm; lsm++) |
| if (is_enabled(*lsm)) |
| pr_cont("%s%s", first++ == 0 ? "" : ",", (*lsm)->name); |
| |
| pr_cont("\n"); |
| } |
| |
| static void __init ordered_lsm_init(void) |
| { |
| struct lsm_info **lsm; |
| |
| ordered_lsms = kcalloc(LSM_COUNT + 1, sizeof(*ordered_lsms), |
| GFP_KERNEL); |
| |
| if (chosen_lsm_order) { |
| if (chosen_major_lsm) { |
| pr_warn("security=%s is ignored because it is superseded by lsm=%s\n", |
| chosen_major_lsm, chosen_lsm_order); |
| chosen_major_lsm = NULL; |
| } |
| ordered_lsm_parse(chosen_lsm_order, "cmdline"); |
| } else |
| ordered_lsm_parse(builtin_lsm_order, "builtin"); |
| |
| for (lsm = ordered_lsms; *lsm; lsm++) |
| prepare_lsm(*lsm); |
| |
| report_lsm_order(); |
| |
| init_debug("cred blob size = %d\n", blob_sizes.lbs_cred); |
| init_debug("file blob size = %d\n", blob_sizes.lbs_file); |
| init_debug("inode blob size = %d\n", blob_sizes.lbs_inode); |
| init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); |
| init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); |
| init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); |
| init_debug("task blob size = %d\n", blob_sizes.lbs_task); |
| init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr_count); |
| |
| /* |
| * Create any kmem_caches needed for blobs |
| */ |
| if (blob_sizes.lbs_file) |
| lsm_file_cache = kmem_cache_create("lsm_file_cache", |
| blob_sizes.lbs_file, 0, |
| SLAB_PANIC, NULL); |
| if (blob_sizes.lbs_inode) |
| lsm_inode_cache = kmem_cache_create("lsm_inode_cache", |
| blob_sizes.lbs_inode, 0, |
| SLAB_PANIC, NULL); |
| |
| lsm_early_cred((struct cred *) current->cred); |
| lsm_early_task(current); |
| for (lsm = ordered_lsms; *lsm; lsm++) |
| initialize_lsm(*lsm); |
| |
| kfree(ordered_lsms); |
| } |
| |
| int __init early_security_init(void) |
| { |
| struct lsm_info *lsm; |
| |
| #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ |
| INIT_HLIST_HEAD(&security_hook_heads.NAME); |
| #include "linux/lsm_hook_defs.h" |
| #undef LSM_HOOK |
| |
| for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { |
| if (!lsm->enabled) |
| lsm->enabled = &lsm_enabled_true; |
| prepare_lsm(lsm); |
| initialize_lsm(lsm); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * security_init - initializes the security framework |
| * |
| * This should be called early in the kernel initialization sequence. |
| */ |
| int __init security_init(void) |
| { |
| struct lsm_info *lsm; |
| |
| init_debug("legacy security=%s\n", chosen_major_lsm ? : " *unspecified*"); |
| init_debug(" CONFIG_LSM=%s\n", builtin_lsm_order); |
| init_debug("boot arg lsm=%s\n", chosen_lsm_order ? : " *unspecified*"); |
| |
| /* |
| * Append the names of the early LSM modules now that kmalloc() is |
| * available |
| */ |
| for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) { |
| init_debug(" early started: %s (%s)\n", lsm->name, |
| is_enabled(lsm) ? "enabled" : "disabled"); |
| if (lsm->enabled) |
| lsm_append(lsm->name, &lsm_names); |
| } |
| |
| /* Load LSMs in specified order. */ |
| ordered_lsm_init(); |
| |
| return 0; |
| } |
| |
| /* Save user chosen LSM */ |
| static int __init choose_major_lsm(char *str) |
| { |
| chosen_major_lsm = str; |
| return 1; |
| } |
| __setup("security=", choose_major_lsm); |
| |
| /* Explicitly choose LSM initialization order. */ |
| static int __init choose_lsm_order(char *str) |
| { |
| chosen_lsm_order = str; |
| return 1; |
| } |
| __setup("lsm=", choose_lsm_order); |
| |
| /* Enable LSM order debugging. */ |
| static int __init enable_debug(char *str) |
| { |
| debug = true; |
| return 1; |
| } |
| __setup("lsm.debug", enable_debug); |
| |
| static bool match_last_lsm(const char *list, const char *lsm) |
| { |
| const char *last; |
| |
| if (WARN_ON(!list || !lsm)) |
| return false; |
| last = strrchr(list, ','); |
| if (last) |
| /* Pass the comma, strcmp() will check for '\0' */ |
| last++; |
| else |
| last = list; |
| return !strcmp(last, lsm); |
| } |
| |
| static int lsm_append(const char *new, char **result) |
| { |
| char *cp; |
| |
| if (*result == NULL) { |
| *result = kstrdup(new, GFP_KERNEL); |
| if (*result == NULL) |
| return -ENOMEM; |
| } else { |
| /* Check if it is the last registered name */ |
| if (match_last_lsm(*result, new)) |
| return 0; |
| cp = kasprintf(GFP_KERNEL, "%s,%s", *result, new); |
| if (cp == NULL) |
| return -ENOMEM; |
| kfree(*result); |
| *result = cp; |
| } |
| return 0; |
| } |
| |
| /** |
| * security_add_hooks - Add a modules hooks to the hook lists. |
| * @hooks: the hooks to add |
| * @count: the number of hooks to add |
| * @lsmid: the identification information for the security module |
| * |
| * Each LSM has to register its hooks with the infrastructure. |
| */ |
| void __init security_add_hooks(struct security_hook_list *hooks, int count, |
| const struct lsm_id *lsmid) |
| { |
| int i; |
| |
| /* |
| * A security module may call security_add_hooks() more |
| * than once during initialization, and LSM initialization |
| * is serialized. Landlock is one such case. |
| * Look at the previous entry, if there is one, for duplication. |
| */ |
| if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid) { |
| if (lsm_active_cnt >= LSM_CONFIG_COUNT) |
| panic("%s Too many LSMs registered.\n", __func__); |
| lsm_idlist[lsm_active_cnt++] = lsmid; |
| } |
| |
| for (i = 0; i < count; i++) { |
| hooks[i].lsmid = lsmid; |
| hlist_add_tail_rcu(&hooks[i].list, hooks[i].head); |
| } |
| |
| /* |
| * Don't try to append during early_security_init(), we'll come back |
| * and fix this up afterwards. |
| */ |
| if (slab_is_available()) { |
| if (lsm_append(lsmid->name, &lsm_names) < 0) |
| panic("%s - Cannot get early memory.\n", __func__); |
| } |
| } |
| |
| int call_blocking_lsm_notifier(enum lsm_event event, void *data) |
| { |
| return blocking_notifier_call_chain(&blocking_lsm_notifier_chain, |
| event, data); |
| } |
| EXPORT_SYMBOL(call_blocking_lsm_notifier); |
| |
| int register_blocking_lsm_notifier(struct notifier_block *nb) |
| { |
| return blocking_notifier_chain_register(&blocking_lsm_notifier_chain, |
| nb); |
| } |
| EXPORT_SYMBOL(register_blocking_lsm_notifier); |
| |
| int unregister_blocking_lsm_notifier(struct notifier_block *nb) |
| { |
| return blocking_notifier_chain_unregister(&blocking_lsm_notifier_chain, |
| nb); |
| } |
| EXPORT_SYMBOL(unregister_blocking_lsm_notifier); |
| |
| /** |
| * lsm_cred_alloc - allocate a composite cred blob |
| * @cred: the cred that needs a blob |
| * @gfp: allocation type |
| * |
| * Allocate the cred blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| static int lsm_cred_alloc(struct cred *cred, gfp_t gfp) |
| { |
| if (blob_sizes.lbs_cred == 0) { |
| cred->security = NULL; |
| return 0; |
| } |
| |
| cred->security = kzalloc(blob_sizes.lbs_cred, gfp); |
| if (cred->security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_early_cred - during initialization allocate a composite cred blob |
| * @cred: the cred that needs a blob |
| * |
| * Allocate the cred blob for all the modules |
| */ |
| static void __init lsm_early_cred(struct cred *cred) |
| { |
| int rc = lsm_cred_alloc(cred, GFP_KERNEL); |
| |
| if (rc) |
| panic("%s: Early cred alloc failed.\n", __func__); |
| } |
| |
| /** |
| * lsm_file_alloc - allocate a composite file blob |
| * @file: the file that needs a blob |
| * |
| * Allocate the file blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| static int lsm_file_alloc(struct file *file) |
| { |
| if (!lsm_file_cache) { |
| file->f_security = NULL; |
| return 0; |
| } |
| |
| file->f_security = kmem_cache_zalloc(lsm_file_cache, GFP_KERNEL); |
| if (file->f_security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_inode_alloc - allocate a composite inode blob |
| * @inode: the inode that needs a blob |
| * |
| * Allocate the inode blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| int lsm_inode_alloc(struct inode *inode) |
| { |
| if (!lsm_inode_cache) { |
| inode->i_security = NULL; |
| return 0; |
| } |
| |
| inode->i_security = kmem_cache_zalloc(lsm_inode_cache, GFP_NOFS); |
| if (inode->i_security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_task_alloc - allocate a composite task blob |
| * @task: the task that needs a blob |
| * |
| * Allocate the task blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| static int lsm_task_alloc(struct task_struct *task) |
| { |
| if (blob_sizes.lbs_task == 0) { |
| task->security = NULL; |
| return 0; |
| } |
| |
| task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL); |
| if (task->security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_ipc_alloc - allocate a composite ipc blob |
| * @kip: the ipc that needs a blob |
| * |
| * Allocate the ipc blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| static int lsm_ipc_alloc(struct kern_ipc_perm *kip) |
| { |
| if (blob_sizes.lbs_ipc == 0) { |
| kip->security = NULL; |
| return 0; |
| } |
| |
| kip->security = kzalloc(blob_sizes.lbs_ipc, GFP_KERNEL); |
| if (kip->security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_msg_msg_alloc - allocate a composite msg_msg blob |
| * @mp: the msg_msg that needs a blob |
| * |
| * Allocate the ipc blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| static int lsm_msg_msg_alloc(struct msg_msg *mp) |
| { |
| if (blob_sizes.lbs_msg_msg == 0) { |
| mp->security = NULL; |
| return 0; |
| } |
| |
| mp->security = kzalloc(blob_sizes.lbs_msg_msg, GFP_KERNEL); |
| if (mp->security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_early_task - during initialization allocate a composite task blob |
| * @task: the task that needs a blob |
| * |
| * Allocate the task blob for all the modules |
| */ |
| static void __init lsm_early_task(struct task_struct *task) |
| { |
| int rc = lsm_task_alloc(task); |
| |
| if (rc) |
| panic("%s: Early task alloc failed.\n", __func__); |
| } |
| |
| /** |
| * lsm_superblock_alloc - allocate a composite superblock blob |
| * @sb: the superblock that needs a blob |
| * |
| * Allocate the superblock blob for all the modules |
| * |
| * Returns 0, or -ENOMEM if memory can't be allocated. |
| */ |
| static int lsm_superblock_alloc(struct super_block *sb) |
| { |
| if (blob_sizes.lbs_superblock == 0) { |
| sb->s_security = NULL; |
| return 0; |
| } |
| |
| sb->s_security = kzalloc(blob_sizes.lbs_superblock, GFP_KERNEL); |
| if (sb->s_security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * lsm_fill_user_ctx - Fill a user space lsm_ctx structure |
| * @uctx: a userspace LSM context to be filled |
| * @uctx_len: available uctx size (input), used uctx size (output) |
| * @val: the new LSM context value |
| * @val_len: the size of the new LSM context value |
| * @id: LSM id |
| * @flags: LSM defined flags |
| * |
| * Fill all of the fields in a userspace lsm_ctx structure. If @uctx is NULL |
| * simply calculate the required size to output via @utc_len and return |
| * success. |
| * |
| * Returns 0 on success, -E2BIG if userspace buffer is not large enough, |
| * -EFAULT on a copyout error, -ENOMEM if memory can't be allocated. |
| */ |
| int lsm_fill_user_ctx(struct lsm_ctx __user *uctx, u32 *uctx_len, |
| void *val, size_t val_len, |
| u64 id, u64 flags) |
| { |
| struct lsm_ctx *nctx = NULL; |
| size_t nctx_len; |
| int rc = 0; |
| |
| nctx_len = ALIGN(struct_size(nctx, ctx, val_len), sizeof(void *)); |
| if (nctx_len > *uctx_len) { |
| rc = -E2BIG; |
| goto out; |
| } |
| |
| /* no buffer - return success/0 and set @uctx_len to the req size */ |
| if (!uctx) |
| goto out; |
| |
| nctx = kzalloc(nctx_len, GFP_KERNEL); |
| if (nctx == NULL) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| nctx->id = id; |
| nctx->flags = flags; |
| nctx->len = nctx_len; |
| nctx->ctx_len = val_len; |
| memcpy(nctx->ctx, val, val_len); |
| |
| if (copy_to_user(uctx, nctx, nctx_len)) |
| rc = -EFAULT; |
| |
| out: |
| kfree(nctx); |
| *uctx_len = nctx_len; |
| return rc; |
| } |
| |
| /* |
| * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and |
| * can be accessed with: |
| * |
| * LSM_RET_DEFAULT(<hook_name>) |
| * |
| * The macros below define static constants for the default value of each |
| * LSM hook. |
| */ |
| #define LSM_RET_DEFAULT(NAME) (NAME##_default) |
| #define DECLARE_LSM_RET_DEFAULT_void(DEFAULT, NAME) |
| #define DECLARE_LSM_RET_DEFAULT_int(DEFAULT, NAME) \ |
| static const int __maybe_unused LSM_RET_DEFAULT(NAME) = (DEFAULT); |
| #define LSM_HOOK(RET, DEFAULT, NAME, ...) \ |
| DECLARE_LSM_RET_DEFAULT_##RET(DEFAULT, NAME) |
| |
| #include <linux/lsm_hook_defs.h> |
| #undef LSM_HOOK |
| |
| /* |
| * Hook list operation macros. |
| * |
| * call_void_hook: |
| * This is a hook that does not return a value. |
| * |
| * call_int_hook: |
| * This is a hook that returns a value. |
| */ |
| |
| #define call_void_hook(FUNC, ...) \ |
| do { \ |
| struct security_hook_list *P; \ |
| \ |
| hlist_for_each_entry(P, &security_hook_heads.FUNC, list) \ |
| P->hook.FUNC(__VA_ARGS__); \ |
| } while (0) |
| |
| #define call_int_hook(FUNC, ...) ({ \ |
| int RC = LSM_RET_DEFAULT(FUNC); \ |
| do { \ |
| struct security_hook_list *P; \ |
| \ |
| hlist_for_each_entry(P, &security_hook_heads.FUNC, list) { \ |
| RC = P->hook.FUNC(__VA_ARGS__); \ |
| if (RC != LSM_RET_DEFAULT(FUNC)) \ |
| break; \ |
| } \ |
| } while (0); \ |
| RC; \ |
| }) |
| |
| /* Security operations */ |
| |
| /** |
| * security_binder_set_context_mgr() - Check if becoming binder ctx mgr is ok |
| * @mgr: task credentials of current binder process |
| * |
| * Check whether @mgr is allowed to be the binder context manager. |
| * |
| * Return: Return 0 if permission is granted. |
| */ |
| int security_binder_set_context_mgr(const struct cred *mgr) |
| { |
| return call_int_hook(binder_set_context_mgr, mgr); |
| } |
| |
| /** |
| * security_binder_transaction() - Check if a binder transaction is allowed |
| * @from: sending process |
| * @to: receiving process |
| * |
| * Check whether @from is allowed to invoke a binder transaction call to @to. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_binder_transaction(const struct cred *from, |
| const struct cred *to) |
| { |
| return call_int_hook(binder_transaction, from, to); |
| } |
| |
| /** |
| * security_binder_transfer_binder() - Check if a binder transfer is allowed |
| * @from: sending process |
| * @to: receiving process |
| * |
| * Check whether @from is allowed to transfer a binder reference to @to. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_binder_transfer_binder(const struct cred *from, |
| const struct cred *to) |
| { |
| return call_int_hook(binder_transfer_binder, from, to); |
| } |
| |
| /** |
| * security_binder_transfer_file() - Check if a binder file xfer is allowed |
| * @from: sending process |
| * @to: receiving process |
| * @file: file being transferred |
| * |
| * Check whether @from is allowed to transfer @file to @to. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_binder_transfer_file(const struct cred *from, |
| const struct cred *to, const struct file *file) |
| { |
| return call_int_hook(binder_transfer_file, from, to, file); |
| } |
| |
| /** |
| * security_ptrace_access_check() - Check if tracing is allowed |
| * @child: target process |
| * @mode: PTRACE_MODE flags |
| * |
| * Check permission before allowing the current process to trace the @child |
| * process. Security modules may also want to perform a process tracing check |
| * during an execve in the set_security or apply_creds hooks of tracing check |
| * during an execve in the bprm_set_creds hook of binprm_security_ops if the |
| * process is being traced and its security attributes would be changed by the |
| * execve. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_ptrace_access_check(struct task_struct *child, unsigned int mode) |
| { |
| return call_int_hook(ptrace_access_check, child, mode); |
| } |
| |
| /** |
| * security_ptrace_traceme() - Check if tracing is allowed |
| * @parent: tracing process |
| * |
| * Check that the @parent process has sufficient permission to trace the |
| * current process before allowing the current process to present itself to the |
| * @parent process for tracing. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_ptrace_traceme(struct task_struct *parent) |
| { |
| return call_int_hook(ptrace_traceme, parent); |
| } |
| |
| /** |
| * security_capget() - Get the capability sets for a process |
| * @target: target process |
| * @effective: effective capability set |
| * @inheritable: inheritable capability set |
| * @permitted: permitted capability set |
| * |
| * Get the @effective, @inheritable, and @permitted capability sets for the |
| * @target process. The hook may also perform permission checking to determine |
| * if the current process is allowed to see the capability sets of the @target |
| * process. |
| * |
| * Return: Returns 0 if the capability sets were successfully obtained. |
| */ |
| int security_capget(const struct task_struct *target, |
| kernel_cap_t *effective, |
| kernel_cap_t *inheritable, |
| kernel_cap_t *permitted) |
| { |
| return call_int_hook(capget, target, effective, inheritable, permitted); |
| } |
| |
| /** |
| * security_capset() - Set the capability sets for a process |
| * @new: new credentials for the target process |
| * @old: current credentials of the target process |
| * @effective: effective capability set |
| * @inheritable: inheritable capability set |
| * @permitted: permitted capability set |
| * |
| * Set the @effective, @inheritable, and @permitted capability sets for the |
| * current process. |
| * |
| * Return: Returns 0 and update @new if permission is granted. |
| */ |
| int security_capset(struct cred *new, const struct cred *old, |
| const kernel_cap_t *effective, |
| const kernel_cap_t *inheritable, |
| const kernel_cap_t *permitted) |
| { |
| return call_int_hook(capset, new, old, effective, inheritable, |
| permitted); |
| } |
| |
| /** |
| * security_capable() - Check if a process has the necessary capability |
| * @cred: credentials to examine |
| * @ns: user namespace |
| * @cap: capability requested |
| * @opts: capability check options |
| * |
| * Check whether the @tsk process has the @cap capability in the indicated |
| * credentials. @cap contains the capability <include/linux/capability.h>. |
| * @opts contains options for the capable check <include/linux/security.h>. |
| * |
| * Return: Returns 0 if the capability is granted. |
| */ |
| int security_capable(const struct cred *cred, |
| struct user_namespace *ns, |
| int cap, |
| unsigned int opts) |
| { |
| return call_int_hook(capable, cred, ns, cap, opts); |
| } |
| |
| /** |
| * security_quotactl() - Check if a quotactl() syscall is allowed for this fs |
| * @cmds: commands |
| * @type: type |
| * @id: id |
| * @sb: filesystem |
| * |
| * Check whether the quotactl syscall is allowed for this @sb. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_quotactl(int cmds, int type, int id, const struct super_block *sb) |
| { |
| return call_int_hook(quotactl, cmds, type, id, sb); |
| } |
| |
| /** |
| * security_quota_on() - Check if QUOTAON is allowed for a dentry |
| * @dentry: dentry |
| * |
| * Check whether QUOTAON is allowed for @dentry. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_quota_on(struct dentry *dentry) |
| { |
| return call_int_hook(quota_on, dentry); |
| } |
| |
| /** |
| * security_syslog() - Check if accessing the kernel message ring is allowed |
| * @type: SYSLOG_ACTION_* type |
| * |
| * Check permission before accessing the kernel message ring or changing |
| * logging to the console. See the syslog(2) manual page for an explanation of |
| * the @type values. |
| * |
| * Return: Return 0 if permission is granted. |
| */ |
| int security_syslog(int type) |
| { |
| return call_int_hook(syslog, type); |
| } |
| |
| /** |
| * security_settime64() - Check if changing the system time is allowed |
| * @ts: new time |
| * @tz: timezone |
| * |
| * Check permission to change the system time, struct timespec64 is defined in |
| * <include/linux/time64.h> and timezone is defined in <include/linux/time.h>. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_settime64(const struct timespec64 *ts, const struct timezone *tz) |
| { |
| return call_int_hook(settime, ts, tz); |
| } |
| |
| /** |
| * security_vm_enough_memory_mm() - Check if allocating a new mem map is allowed |
| * @mm: mm struct |
| * @pages: number of pages |
| * |
| * Check permissions for allocating a new virtual mapping. If all LSMs return |
| * a positive value, __vm_enough_memory() will be called with cap_sys_admin |
| * set. If at least one LSM returns 0 or negative, __vm_enough_memory() will be |
| * called with cap_sys_admin cleared. |
| * |
| * Return: Returns 0 if permission is granted by the LSM infrastructure to the |
| * caller. |
| */ |
| int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) |
| { |
| struct security_hook_list *hp; |
| int cap_sys_admin = 1; |
| int rc; |
| |
| /* |
| * The module will respond with a positive value if |
| * it thinks the __vm_enough_memory() call should be |
| * made with the cap_sys_admin set. If all of the modules |
| * agree that it should be set it will. If any module |
| * thinks it should not be set it won't. |
| */ |
| hlist_for_each_entry(hp, &security_hook_heads.vm_enough_memory, list) { |
| rc = hp->hook.vm_enough_memory(mm, pages); |
| if (rc <= 0) { |
| cap_sys_admin = 0; |
| break; |
| } |
| } |
| return __vm_enough_memory(mm, pages, cap_sys_admin); |
| } |
| |
| /** |
| * security_bprm_creds_for_exec() - Prepare the credentials for exec() |
| * @bprm: binary program information |
| * |
| * If the setup in prepare_exec_creds did not setup @bprm->cred->security |
| * properly for executing @bprm->file, update the LSM's portion of |
| * @bprm->cred->security to be what commit_creds needs to install for the new |
| * program. This hook may also optionally check permissions (e.g. for |
| * transitions between security domains). The hook must set @bprm->secureexec |
| * to 1 if AT_SECURE should be set to request libc enable secure mode. @bprm |
| * contains the linux_binprm structure. |
| * |
| * Return: Returns 0 if the hook is successful and permission is granted. |
| */ |
| int security_bprm_creds_for_exec(struct linux_binprm *bprm) |
| { |
| return call_int_hook(bprm_creds_for_exec, bprm); |
| } |
| |
| /** |
| * security_bprm_creds_from_file() - Update linux_binprm creds based on file |
| * @bprm: binary program information |
| * @file: associated file |
| * |
| * If @file is setpcap, suid, sgid or otherwise marked to change privilege upon |
| * exec, update @bprm->cred to reflect that change. This is called after |
| * finding the binary that will be executed without an interpreter. This |
| * ensures that the credentials will not be derived from a script that the |
| * binary will need to reopen, which when reopend may end up being a completely |
| * different file. This hook may also optionally check permissions (e.g. for |
| * transitions between security domains). The hook must set @bprm->secureexec |
| * to 1 if AT_SECURE should be set to request libc enable secure mode. The |
| * hook must add to @bprm->per_clear any personality flags that should be |
| * cleared from current->personality. @bprm contains the linux_binprm |
| * structure. |
| * |
| * Return: Returns 0 if the hook is successful and permission is granted. |
| */ |
| int security_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file) |
| { |
| return call_int_hook(bprm_creds_from_file, bprm, file); |
| } |
| |
| /** |
| * security_bprm_check() - Mediate binary handler search |
| * @bprm: binary program information |
| * |
| * This hook mediates the point when a search for a binary handler will begin. |
| * It allows a check against the @bprm->cred->security value which was set in |
| * the preceding creds_for_exec call. The argv list and envp list are reliably |
| * available in @bprm. This hook may be called multiple times during a single |
| * execve. @bprm contains the linux_binprm structure. |
| * |
| * Return: Returns 0 if the hook is successful and permission is granted. |
| */ |
| int security_bprm_check(struct linux_binprm *bprm) |
| { |
| return call_int_hook(bprm_check_security, bprm); |
| } |
| |
| /** |
| * security_bprm_committing_creds() - Install creds for a process during exec() |
| * @bprm: binary program information |
| * |
| * Prepare to install the new security attributes of a process being |
| * transformed by an execve operation, based on the old credentials pointed to |
| * by @current->cred and the information set in @bprm->cred by the |
| * bprm_creds_for_exec hook. @bprm points to the linux_binprm structure. This |
| * hook is a good place to perform state changes on the process such as closing |
| * open file descriptors to which access will no longer be granted when the |
| * attributes are changed. This is called immediately before commit_creds(). |
| */ |
| void security_bprm_committing_creds(const struct linux_binprm *bprm) |
| { |
| call_void_hook(bprm_committing_creds, bprm); |
| } |
| |
| /** |
| * security_bprm_committed_creds() - Tidy up after cred install during exec() |
| * @bprm: binary program information |
| * |
| * Tidy up after the installation of the new security attributes of a process |
| * being transformed by an execve operation. The new credentials have, by this |
| * point, been set to @current->cred. @bprm points to the linux_binprm |
| * structure. This hook is a good place to perform state changes on the |
| * process such as clearing out non-inheritable signal state. This is called |
| * immediately after commit_creds(). |
| */ |
| void security_bprm_committed_creds(const struct linux_binprm *bprm) |
| { |
| call_void_hook(bprm_committed_creds, bprm); |
| } |
| |
| /** |
| * security_fs_context_submount() - Initialise fc->security |
| * @fc: new filesystem context |
| * @reference: dentry reference for submount/remount |
| * |
| * Fill out the ->security field for a new fs_context. |
| * |
| * Return: Returns 0 on success or negative error code on failure. |
| */ |
| int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) |
| { |
| return call_int_hook(fs_context_submount, fc, reference); |
| } |
| |
| /** |
| * security_fs_context_dup() - Duplicate a fs_context LSM blob |
| * @fc: destination filesystem context |
| * @src_fc: source filesystem context |
| * |
| * Allocate and attach a security structure to sc->security. This pointer is |
| * initialised to NULL by the caller. @fc indicates the new filesystem context. |
| * @src_fc indicates the original filesystem context. |
| * |
| * Return: Returns 0 on success or a negative error code on failure. |
| */ |
| int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) |
| { |
| return call_int_hook(fs_context_dup, fc, src_fc); |
| } |
| |
| /** |
| * security_fs_context_parse_param() - Configure a filesystem context |
| * @fc: filesystem context |
| * @param: filesystem parameter |
| * |
| * Userspace provided a parameter to configure a superblock. The LSM can |
| * consume the parameter or return it to the caller for use elsewhere. |
| * |
| * Return: If the parameter is used by the LSM it should return 0, if it is |
| * returned to the caller -ENOPARAM is returned, otherwise a negative |
| * error code is returned. |
| */ |
| int security_fs_context_parse_param(struct fs_context *fc, |
| struct fs_parameter *param) |
| { |
| struct security_hook_list *hp; |
| int trc; |
| int rc = -ENOPARAM; |
| |
| hlist_for_each_entry(hp, &security_hook_heads.fs_context_parse_param, |
| list) { |
| trc = hp->hook.fs_context_parse_param(fc, param); |
| if (trc == 0) |
| rc = 0; |
| else if (trc != -ENOPARAM) |
| return trc; |
| } |
| return rc; |
| } |
| |
| /** |
| * security_sb_alloc() - Allocate a super_block LSM blob |
| * @sb: filesystem superblock |
| * |
| * Allocate and attach a security structure to the sb->s_security field. The |
| * s_security field is initialized to NULL when the structure is allocated. |
| * @sb contains the super_block structure to be modified. |
| * |
| * Return: Returns 0 if operation was successful. |
| */ |
| int security_sb_alloc(struct super_block *sb) |
| { |
| int rc = lsm_superblock_alloc(sb); |
| |
| if (unlikely(rc)) |
| return rc; |
| rc = call_int_hook(sb_alloc_security, sb); |
| if (unlikely(rc)) |
| security_sb_free(sb); |
| return rc; |
| } |
| |
| /** |
| * security_sb_delete() - Release super_block LSM associated objects |
| * @sb: filesystem superblock |
| * |
| * Release objects tied to a superblock (e.g. inodes). @sb contains the |
| * super_block structure being released. |
| */ |
| void security_sb_delete(struct super_block *sb) |
| { |
| call_void_hook(sb_delete, sb); |
| } |
| |
| /** |
| * security_sb_free() - Free a super_block LSM blob |
| * @sb: filesystem superblock |
| * |
| * Deallocate and clear the sb->s_security field. @sb contains the super_block |
| * structure to be modified. |
| */ |
| void security_sb_free(struct super_block *sb) |
| { |
| call_void_hook(sb_free_security, sb); |
| kfree(sb->s_security); |
| sb->s_security = NULL; |
| } |
| |
| /** |
| * security_free_mnt_opts() - Free memory associated with mount options |
| * @mnt_opts: LSM processed mount options |
| * |
| * Free memory associated with @mnt_ops. |
| */ |
| void security_free_mnt_opts(void **mnt_opts) |
| { |
| if (!*mnt_opts) |
| return; |
| call_void_hook(sb_free_mnt_opts, *mnt_opts); |
| *mnt_opts = NULL; |
| } |
| EXPORT_SYMBOL(security_free_mnt_opts); |
| |
| /** |
| * security_sb_eat_lsm_opts() - Consume LSM mount options |
| * @options: mount options |
| * @mnt_opts: LSM processed mount options |
| * |
| * Eat (scan @options) and save them in @mnt_opts. |
| * |
| * Return: Returns 0 on success, negative values on failure. |
| */ |
| int security_sb_eat_lsm_opts(char *options, void **mnt_opts) |
| { |
| return call_int_hook(sb_eat_lsm_opts, options, mnt_opts); |
| } |
| EXPORT_SYMBOL(security_sb_eat_lsm_opts); |
| |
| /** |
| * security_sb_mnt_opts_compat() - Check if new mount options are allowed |
| * @sb: filesystem superblock |
| * @mnt_opts: new mount options |
| * |
| * Determine if the new mount options in @mnt_opts are allowed given the |
| * existing mounted filesystem at @sb. @sb superblock being compared. |
| * |
| * Return: Returns 0 if options are compatible. |
| */ |
| int security_sb_mnt_opts_compat(struct super_block *sb, |
| void *mnt_opts) |
| { |
| return call_int_hook(sb_mnt_opts_compat, sb, mnt_opts); |
| } |
| EXPORT_SYMBOL(security_sb_mnt_opts_compat); |
| |
| /** |
| * security_sb_remount() - Verify no incompatible mount changes during remount |
| * @sb: filesystem superblock |
| * @mnt_opts: (re)mount options |
| * |
| * Extracts security system specific mount options and verifies no changes are |
| * being made to those options. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_sb_remount(struct super_block *sb, |
| void *mnt_opts) |
| { |
| return call_int_hook(sb_remount, sb, mnt_opts); |
| } |
| EXPORT_SYMBOL(security_sb_remount); |
| |
| /** |
| * security_sb_kern_mount() - Check if a kernel mount is allowed |
| * @sb: filesystem superblock |
| * |
| * Mount this @sb if allowed by permissions. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_sb_kern_mount(const struct super_block *sb) |
| { |
| return call_int_hook(sb_kern_mount, sb); |
| } |
| |
| /** |
| * security_sb_show_options() - Output the mount options for a superblock |
| * @m: output file |
| * @sb: filesystem superblock |
| * |
| * Show (print on @m) mount options for this @sb. |
| * |
| * Return: Returns 0 on success, negative values on failure. |
| */ |
| int security_sb_show_options(struct seq_file *m, struct super_block *sb) |
| { |
| return call_int_hook(sb_show_options, m, sb); |
| } |
| |
| /** |
| * security_sb_statfs() - Check if accessing fs stats is allowed |
| * @dentry: superblock handle |
| * |
| * Check permission before obtaining filesystem statistics for the @mnt |
| * mountpoint. @dentry is a handle on the superblock for the filesystem. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_sb_statfs(struct dentry *dentry) |
| { |
| return call_int_hook(sb_statfs, dentry); |
| } |
| |
| /** |
| * security_sb_mount() - Check permission for mounting a filesystem |
| * @dev_name: filesystem backing device |
| * @path: mount point |
| * @type: filesystem type |
| * @flags: mount flags |
| * @data: filesystem specific data |
| * |
| * Check permission before an object specified by @dev_name is mounted on the |
| * mount point named by @nd. For an ordinary mount, @dev_name identifies a |
| * device if the file system type requires a device. For a remount |
| * (@flags & MS_REMOUNT), @dev_name is irrelevant. For a loopback/bind mount |
| * (@flags & MS_BIND), @dev_name identifies the pathname of the object being |
| * mounted. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_sb_mount(const char *dev_name, const struct path *path, |
| const char *type, unsigned long flags, void *data) |
| { |
| return call_int_hook(sb_mount, dev_name, path, type, flags, data); |
| } |
| |
| /** |
| * security_sb_umount() - Check permission for unmounting a filesystem |
| * @mnt: mounted filesystem |
| * @flags: unmount flags |
| * |
| * Check permission before the @mnt file system is unmounted. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_sb_umount(struct vfsmount *mnt, int flags) |
| { |
| return call_int_hook(sb_umount, mnt, flags); |
| } |
| |
| /** |
| * security_sb_pivotroot() - Check permissions for pivoting the rootfs |
| * @old_path: new location for current rootfs |
| * @new_path: location of the new rootfs |
| * |
| * Check permission before pivoting the root filesystem. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_sb_pivotroot(const struct path *old_path, |
| const struct path *new_path) |
| { |
| return call_int_hook(sb_pivotroot, old_path, new_path); |
| } |
| |
| /** |
| * security_sb_set_mnt_opts() - Set the mount options for a filesystem |
| * @sb: filesystem superblock |
| * @mnt_opts: binary mount options |
| * @kern_flags: kernel flags (in) |
| * @set_kern_flags: kernel flags (out) |
| * |
| * Set the security relevant mount options used for a superblock. |
| * |
| * Return: Returns 0 on success, error on failure. |
| */ |
| int security_sb_set_mnt_opts(struct super_block *sb, |
| void *mnt_opts, |
| unsigned long kern_flags, |
| unsigned long *set_kern_flags) |
| { |
| struct security_hook_list *hp; |
| int rc = mnt_opts ? -EOPNOTSUPP : LSM_RET_DEFAULT(sb_set_mnt_opts); |
| |
| hlist_for_each_entry(hp, &security_hook_heads.sb_set_mnt_opts, |
| list) { |
| rc = hp->hook.sb_set_mnt_opts(sb, mnt_opts, kern_flags, |
| set_kern_flags); |
| if (rc != LSM_RET_DEFAULT(sb_set_mnt_opts)) |
| break; |
| } |
| return rc; |
| } |
| EXPORT_SYMBOL(security_sb_set_mnt_opts); |
| |
| /** |
| * security_sb_clone_mnt_opts() - Duplicate superblock mount options |
| * @oldsb: source superblock |
| * @newsb: destination superblock |
| * @kern_flags: kernel flags (in) |
| * @set_kern_flags: kernel flags (out) |
| * |
| * Copy all security options from a given superblock to another. |
| * |
| * Return: Returns 0 on success, error on failure. |
| */ |
| int security_sb_clone_mnt_opts(const struct super_block *oldsb, |
| struct super_block *newsb, |
| unsigned long kern_flags, |
| unsigned long *set_kern_flags) |
| { |
| return call_int_hook(sb_clone_mnt_opts, oldsb, newsb, |
| kern_flags, set_kern_flags); |
| } |
| EXPORT_SYMBOL(security_sb_clone_mnt_opts); |
| |
| /** |
| * security_move_mount() - Check permissions for moving a mount |
| * @from_path: source mount point |
| * @to_path: destination mount point |
| * |
| * Check permission before a mount is moved. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_move_mount(const struct path *from_path, |
| const struct path *to_path) |
| { |
| return call_int_hook(move_mount, from_path, to_path); |
| } |
| |
| /** |
| * security_path_notify() - Check if setting a watch is allowed |
| * @path: file path |
| * @mask: event mask |
| * @obj_type: file path type |
| * |
| * Check permissions before setting a watch on events as defined by @mask, on |
| * an object at @path, whose type is defined by @obj_type. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_notify(const struct path *path, u64 mask, |
| unsigned int obj_type) |
| { |
| return call_int_hook(path_notify, path, mask, obj_type); |
| } |
| |
| /** |
| * security_inode_alloc() - Allocate an inode LSM blob |
| * @inode: the inode |
| * |
| * Allocate and attach a security structure to @inode->i_security. The |
| * i_security field is initialized to NULL when the inode structure is |
| * allocated. |
| * |
| * Return: Return 0 if operation was successful. |
| */ |
| int security_inode_alloc(struct inode *inode) |
| { |
| int rc = lsm_inode_alloc(inode); |
| |
| if (unlikely(rc)) |
| return rc; |
| rc = call_int_hook(inode_alloc_security, inode); |
| if (unlikely(rc)) |
| security_inode_free(inode); |
| return rc; |
| } |
| |
| static void inode_free_by_rcu(struct rcu_head *head) |
| { |
| /* |
| * The rcu head is at the start of the inode blob |
| */ |
| kmem_cache_free(lsm_inode_cache, head); |
| } |
| |
| /** |
| * security_inode_free() - Free an inode's LSM blob |
| * @inode: the inode |
| * |
| * Deallocate the inode security structure and set @inode->i_security to NULL. |
| */ |
| void security_inode_free(struct inode *inode) |
| { |
| call_void_hook(inode_free_security, inode); |
| /* |
| * The inode may still be referenced in a path walk and |
| * a call to security_inode_permission() can be made |
| * after inode_free_security() is called. Ideally, the VFS |
| * wouldn't do this, but fixing that is a much harder |
| * job. For now, simply free the i_security via RCU, and |
| * leave the current inode->i_security pointer intact. |
| * The inode will be freed after the RCU grace period too. |
| */ |
| if (inode->i_security) |
| call_rcu((struct rcu_head *)inode->i_security, |
| inode_free_by_rcu); |
| } |
| |
| /** |
| * security_dentry_init_security() - Perform dentry initialization |
| * @dentry: the dentry to initialize |
| * @mode: mode used to determine resource type |
| * @name: name of the last path component |
| * @xattr_name: name of the security/LSM xattr |
| * @ctx: pointer to the resulting LSM context |
| * @ctxlen: length of @ctx |
| * |
| * Compute a context for a dentry as the inode is not yet available since NFSv4 |
| * has no label backed by an EA anyway. It is important to note that |
| * @xattr_name does not need to be free'd by the caller, it is a static string. |
| * |
| * Return: Returns 0 on success, negative values on failure. |
| */ |
| int security_dentry_init_security(struct dentry *dentry, int mode, |
| const struct qstr *name, |
| const char **xattr_name, void **ctx, |
| u32 *ctxlen) |
| { |
| return call_int_hook(dentry_init_security, dentry, mode, name, |
| xattr_name, ctx, ctxlen); |
| } |
| EXPORT_SYMBOL(security_dentry_init_security); |
| |
| /** |
| * security_dentry_create_files_as() - Perform dentry initialization |
| * @dentry: the dentry to initialize |
| * @mode: mode used to determine resource type |
| * @name: name of the last path component |
| * @old: creds to use for LSM context calculations |
| * @new: creds to modify |
| * |
| * Compute a context for a dentry as the inode is not yet available and set |
| * that context in passed in creds so that new files are created using that |
| * context. Context is calculated using the passed in creds and not the creds |
| * of the caller. |
| * |
| * Return: Returns 0 on success, error on failure. |
| */ |
| int security_dentry_create_files_as(struct dentry *dentry, int mode, |
| struct qstr *name, |
| const struct cred *old, struct cred *new) |
| { |
| return call_int_hook(dentry_create_files_as, dentry, mode, |
| name, old, new); |
| } |
| EXPORT_SYMBOL(security_dentry_create_files_as); |
| |
| /** |
| * security_inode_init_security() - Initialize an inode's LSM context |
| * @inode: the inode |
| * @dir: parent directory |
| * @qstr: last component of the pathname |
| * @initxattrs: callback function to write xattrs |
| * @fs_data: filesystem specific data |
| * |
| * Obtain the security attribute name suffix and value to set on a newly |
| * created inode and set up the incore security field for the new inode. This |
| * hook is called by the fs code as part of the inode creation transaction and |
| * provides for atomic labeling of the inode, unlike the post_create/mkdir/... |
| * hooks called by the VFS. |
| * |
| * The hook function is expected to populate the xattrs array, by calling |
| * lsm_get_xattr_slot() to retrieve the slots reserved by the security module |
| * with the lbs_xattr_count field of the lsm_blob_sizes structure. For each |
| * slot, the hook function should set ->name to the attribute name suffix |
| * (e.g. selinux), to allocate ->value (will be freed by the caller) and set it |
| * to the attribute value, to set ->value_len to the length of the value. If |
| * the security module does not use security attributes or does not wish to put |
| * a security attribute on this particular inode, then it should return |
| * -EOPNOTSUPP to skip this processing. |
| * |
| * Return: Returns 0 if the LSM successfully initialized all of the inode |
| * security attributes that are required, negative values otherwise. |
| */ |
| int security_inode_init_security(struct inode *inode, struct inode *dir, |
| const struct qstr *qstr, |
| const initxattrs initxattrs, void *fs_data) |
| { |
| struct security_hook_list *hp; |
| struct xattr *new_xattrs = NULL; |
| int ret = -EOPNOTSUPP, xattr_count = 0; |
| |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| |
| if (!blob_sizes.lbs_xattr_count) |
| return 0; |
| |
| if (initxattrs) { |
| /* Allocate +1 as terminator. */ |
| new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1, |
| sizeof(*new_xattrs), GFP_NOFS); |
| if (!new_xattrs) |
| return -ENOMEM; |
| } |
| |
| hlist_for_each_entry(hp, &security_hook_heads.inode_init_security, |
| list) { |
| ret = hp->hook.inode_init_security(inode, dir, qstr, new_xattrs, |
| &xattr_count); |
| if (ret && ret != -EOPNOTSUPP) |
| goto out; |
| /* |
| * As documented in lsm_hooks.h, -EOPNOTSUPP in this context |
| * means that the LSM is not willing to provide an xattr, not |
| * that it wants to signal an error. Thus, continue to invoke |
| * the remaining LSMs. |
| */ |
| } |
| |
| /* If initxattrs() is NULL, xattr_count is zero, skip the call. */ |
| if (!xattr_count) |
| goto out; |
| |
| ret = initxattrs(inode, new_xattrs, fs_data); |
| out: |
| for (; xattr_count > 0; xattr_count--) |
| kfree(new_xattrs[xattr_count - 1].value); |
| kfree(new_xattrs); |
| return (ret == -EOPNOTSUPP) ? 0 : ret; |
| } |
| EXPORT_SYMBOL(security_inode_init_security); |
| |
| /** |
| * security_inode_init_security_anon() - Initialize an anonymous inode |
| * @inode: the inode |
| * @name: the anonymous inode class |
| * @context_inode: an optional related inode |
| * |
| * Set up the incore security field for the new anonymous inode and return |
| * whether the inode creation is permitted by the security module or not. |
| * |
| * Return: Returns 0 on success, -EACCES if the security module denies the |
| * creation of this inode, or another -errno upon other errors. |
| */ |
| int security_inode_init_security_anon(struct inode *inode, |
| const struct qstr *name, |
| const struct inode *context_inode) |
| { |
| return call_int_hook(inode_init_security_anon, inode, name, |
| context_inode); |
| } |
| |
| #ifdef CONFIG_SECURITY_PATH |
| /** |
| * security_path_mknod() - Check if creating a special file is allowed |
| * @dir: parent directory |
| * @dentry: new file |
| * @mode: new file mode |
| * @dev: device number |
| * |
| * Check permissions when creating a file. Note that this hook is called even |
| * if mknod operation is being done for a regular file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_mknod(const struct path *dir, struct dentry *dentry, |
| umode_t mode, unsigned int dev) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) |
| return 0; |
| return call_int_hook(path_mknod, dir, dentry, mode, dev); |
| } |
| EXPORT_SYMBOL(security_path_mknod); |
| |
| /** |
| * security_path_post_mknod() - Update inode security after reg file creation |
| * @idmap: idmap of the mount |
| * @dentry: new file |
| * |
| * Update inode security field after a regular file has been created. |
| */ |
| void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return; |
| call_void_hook(path_post_mknod, idmap, dentry); |
| } |
| |
| /** |
| * security_path_mkdir() - Check if creating a new directory is allowed |
| * @dir: parent directory |
| * @dentry: new directory |
| * @mode: new directory mode |
| * |
| * Check permissions to create a new directory in the existing directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_mkdir(const struct path *dir, struct dentry *dentry, |
| umode_t mode) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) |
| return 0; |
| return call_int_hook(path_mkdir, dir, dentry, mode); |
| } |
| EXPORT_SYMBOL(security_path_mkdir); |
| |
| /** |
| * security_path_rmdir() - Check if removing a directory is allowed |
| * @dir: parent directory |
| * @dentry: directory to remove |
| * |
| * Check the permission to remove a directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_rmdir(const struct path *dir, struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) |
| return 0; |
| return call_int_hook(path_rmdir, dir, dentry); |
| } |
| |
| /** |
| * security_path_unlink() - Check if removing a hard link is allowed |
| * @dir: parent directory |
| * @dentry: file |
| * |
| * Check the permission to remove a hard link to a file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_unlink(const struct path *dir, struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) |
| return 0; |
| return call_int_hook(path_unlink, dir, dentry); |
| } |
| EXPORT_SYMBOL(security_path_unlink); |
| |
| /** |
| * security_path_symlink() - Check if creating a symbolic link is allowed |
| * @dir: parent directory |
| * @dentry: symbolic link |
| * @old_name: file pathname |
| * |
| * Check the permission to create a symbolic link to a file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_symlink(const struct path *dir, struct dentry *dentry, |
| const char *old_name) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dir->dentry)))) |
| return 0; |
| return call_int_hook(path_symlink, dir, dentry, old_name); |
| } |
| |
| /** |
| * security_path_link - Check if creating a hard link is allowed |
| * @old_dentry: existing file |
| * @new_dir: new parent directory |
| * @new_dentry: new link |
| * |
| * Check permission before creating a new hard link to a file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_link(struct dentry *old_dentry, const struct path *new_dir, |
| struct dentry *new_dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) |
| return 0; |
| return call_int_hook(path_link, old_dentry, new_dir, new_dentry); |
| } |
| |
| /** |
| * security_path_rename() - Check if renaming a file is allowed |
| * @old_dir: parent directory of the old file |
| * @old_dentry: the old file |
| * @new_dir: parent directory of the new file |
| * @new_dentry: the new file |
| * @flags: flags |
| * |
| * Check for permission to rename a file or directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_rename(const struct path *old_dir, struct dentry *old_dentry, |
| const struct path *new_dir, struct dentry *new_dentry, |
| unsigned int flags) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || |
| (d_is_positive(new_dentry) && |
| IS_PRIVATE(d_backing_inode(new_dentry))))) |
| return 0; |
| |
| return call_int_hook(path_rename, old_dir, old_dentry, new_dir, |
| new_dentry, flags); |
| } |
| EXPORT_SYMBOL(security_path_rename); |
| |
| /** |
| * security_path_truncate() - Check if truncating a file is allowed |
| * @path: file |
| * |
| * Check permission before truncating the file indicated by path. Note that |
| * truncation permissions may also be checked based on already opened files, |
| * using the security_file_truncate() hook. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_truncate(const struct path *path) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) |
| return 0; |
| return call_int_hook(path_truncate, path); |
| } |
| |
| /** |
| * security_path_chmod() - Check if changing the file's mode is allowed |
| * @path: file |
| * @mode: new mode |
| * |
| * Check for permission to change a mode of the file @path. The new mode is |
| * specified in @mode which is a bitmask of constants from |
| * <include/uapi/linux/stat.h>. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_chmod(const struct path *path, umode_t mode) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) |
| return 0; |
| return call_int_hook(path_chmod, path, mode); |
| } |
| |
| /** |
| * security_path_chown() - Check if changing the file's owner/group is allowed |
| * @path: file |
| * @uid: file owner |
| * @gid: file group |
| * |
| * Check for permission to change owner/group of a file or directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_chown(const struct path *path, kuid_t uid, kgid_t gid) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) |
| return 0; |
| return call_int_hook(path_chown, path, uid, gid); |
| } |
| |
| /** |
| * security_path_chroot() - Check if changing the root directory is allowed |
| * @path: directory |
| * |
| * Check for permission to change root directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_path_chroot(const struct path *path) |
| { |
| return call_int_hook(path_chroot, path); |
| } |
| #endif /* CONFIG_SECURITY_PATH */ |
| |
| /** |
| * security_inode_create() - Check if creating a file is allowed |
| * @dir: the parent directory |
| * @dentry: the file being created |
| * @mode: requested file mode |
| * |
| * Check permission to create a regular file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_create(struct inode *dir, struct dentry *dentry, |
| umode_t mode) |
| { |
| if (unlikely(IS_PRIVATE(dir))) |
| return 0; |
| return call_int_hook(inode_create, dir, dentry, mode); |
| } |
| EXPORT_SYMBOL_GPL(security_inode_create); |
| |
| /** |
| * security_inode_post_create_tmpfile() - Update inode security of new tmpfile |
| * @idmap: idmap of the mount |
| * @inode: inode of the new tmpfile |
| * |
| * Update inode security data after a tmpfile has been created. |
| */ |
| void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, |
| struct inode *inode) |
| { |
| if (unlikely(IS_PRIVATE(inode))) |
| return; |
| call_void_hook(inode_post_create_tmpfile, idmap, inode); |
| } |
| |
| /** |
| * security_inode_link() - Check if creating a hard link is allowed |
| * @old_dentry: existing file |
| * @dir: new parent directory |
| * @new_dentry: new link |
| * |
| * Check permission before creating a new hard link to a file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_link(struct dentry *old_dentry, struct inode *dir, |
| struct dentry *new_dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)))) |
| return 0; |
| return call_int_hook(inode_link, old_dentry, dir, new_dentry); |
| } |
| |
| /** |
| * security_inode_unlink() - Check if removing a hard link is allowed |
| * @dir: parent directory |
| * @dentry: file |
| * |
| * Check the permission to remove a hard link to a file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_unlink, dir, dentry); |
| } |
| |
| /** |
| * security_inode_symlink() - Check if creating a symbolic link is allowed |
| * @dir: parent directory |
| * @dentry: symbolic link |
| * @old_name: existing filename |
| * |
| * Check the permission to create a symbolic link to a file. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_symlink(struct inode *dir, struct dentry *dentry, |
| const char *old_name) |
| { |
| if (unlikely(IS_PRIVATE(dir))) |
| return 0; |
| return call_int_hook(inode_symlink, dir, dentry, old_name); |
| } |
| |
| /** |
| * security_inode_mkdir() - Check if creation a new director is allowed |
| * @dir: parent directory |
| * @dentry: new directory |
| * @mode: new directory mode |
| * |
| * Check permissions to create a new directory in the existing directory |
| * associated with inode structure @dir. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
| { |
| if (unlikely(IS_PRIVATE(dir))) |
| return 0; |
| return call_int_hook(inode_mkdir, dir, dentry, mode); |
| } |
| EXPORT_SYMBOL_GPL(security_inode_mkdir); |
| |
| /** |
| * security_inode_rmdir() - Check if removing a directory is allowed |
| * @dir: parent directory |
| * @dentry: directory to be removed |
| * |
| * Check the permission to remove a directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_rmdir, dir, dentry); |
| } |
| |
| /** |
| * security_inode_mknod() - Check if creating a special file is allowed |
| * @dir: parent directory |
| * @dentry: new file |
| * @mode: new file mode |
| * @dev: device number |
| * |
| * Check permissions when creating a special file (or a socket or a fifo file |
| * created via the mknod system call). Note that if mknod operation is being |
| * done for a regular file, then the create hook will be called and not this |
| * hook. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_mknod(struct inode *dir, struct dentry *dentry, |
| umode_t mode, dev_t dev) |
| { |
| if (unlikely(IS_PRIVATE(dir))) |
| return 0; |
| return call_int_hook(inode_mknod, dir, dentry, mode, dev); |
| } |
| |
| /** |
| * security_inode_rename() - Check if renaming a file is allowed |
| * @old_dir: parent directory of the old file |
| * @old_dentry: the old file |
| * @new_dir: parent directory of the new file |
| * @new_dentry: the new file |
| * @flags: flags |
| * |
| * Check for permission to rename a file or directory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry, |
| struct inode *new_dir, struct dentry *new_dentry, |
| unsigned int flags) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(old_dentry)) || |
| (d_is_positive(new_dentry) && |
| IS_PRIVATE(d_backing_inode(new_dentry))))) |
| return 0; |
| |
| if (flags & RENAME_EXCHANGE) { |
| int err = call_int_hook(inode_rename, new_dir, new_dentry, |
| old_dir, old_dentry); |
| if (err) |
| return err; |
| } |
| |
| return call_int_hook(inode_rename, old_dir, old_dentry, |
| new_dir, new_dentry); |
| } |
| |
| /** |
| * security_inode_readlink() - Check if reading a symbolic link is allowed |
| * @dentry: link |
| * |
| * Check the permission to read the symbolic link. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_readlink(struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_readlink, dentry); |
| } |
| |
| /** |
| * security_inode_follow_link() - Check if following a symbolic link is allowed |
| * @dentry: link dentry |
| * @inode: link inode |
| * @rcu: true if in RCU-walk mode |
| * |
| * Check permission to follow a symbolic link when looking up a pathname. If |
| * @rcu is true, @inode is not stable. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_follow_link(struct dentry *dentry, struct inode *inode, |
| bool rcu) |
| { |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| return call_int_hook(inode_follow_link, dentry, inode, rcu); |
| } |
| |
| /** |
| * security_inode_permission() - Check if accessing an inode is allowed |
| * @inode: inode |
| * @mask: access mask |
| * |
| * Check permission before accessing an inode. This hook is called by the |
| * existing Linux permission function, so a security module can use it to |
| * provide additional checking for existing Linux permission checks. Notice |
| * that this hook is called when a file is opened (as well as many other |
| * operations), whereas the file_security_ops permission hook is called when |
| * the actual read/write operations are performed. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_permission(struct inode *inode, int mask) |
| { |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| return call_int_hook(inode_permission, inode, mask); |
| } |
| |
| /** |
| * security_inode_setattr() - Check if setting file attributes is allowed |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @attr: new attributes |
| * |
| * Check permission before setting file attributes. Note that the kernel call |
| * to notify_change is performed from several locations, whenever file |
| * attributes change (such as when a file is truncated, chown/chmod operations, |
| * transferring disk quotas, etc). |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_setattr(struct mnt_idmap *idmap, |
| struct dentry *dentry, struct iattr *attr) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_setattr, idmap, dentry, attr); |
| } |
| EXPORT_SYMBOL_GPL(security_inode_setattr); |
| |
| /** |
| * security_inode_post_setattr() - Update the inode after a setattr operation |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @ia_valid: file attributes set |
| * |
| * Update inode security field after successful setting file attributes. |
| */ |
| void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, |
| int ia_valid) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return; |
| call_void_hook(inode_post_setattr, idmap, dentry, ia_valid); |
| } |
| |
| /** |
| * security_inode_getattr() - Check if getting file attributes is allowed |
| * @path: file |
| * |
| * Check permission before obtaining file attributes. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_getattr(const struct path *path) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(path->dentry)))) |
| return 0; |
| return call_int_hook(inode_getattr, path); |
| } |
| |
| /** |
| * security_inode_setxattr() - Check if setting file xattrs is allowed |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @name: xattr name |
| * @value: xattr value |
| * @size: size of xattr value |
| * @flags: flags |
| * |
| * This hook performs the desired permission checks before setting the extended |
| * attributes (xattrs) on @dentry. It is important to note that we have some |
| * additional logic before the main LSM implementation calls to detect if we |
| * need to perform an additional capability check at the LSM layer. |
| * |
| * Normally we enforce a capability check prior to executing the various LSM |
| * hook implementations, but if a LSM wants to avoid this capability check, |
| * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for |
| * xattrs that it wants to avoid the capability check, leaving the LSM fully |
| * responsible for enforcing the access control for the specific xattr. If all |
| * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, |
| * or return a 0 (the default return value), the capability check is still |
| * performed. If no 'inode_xattr_skipcap' hooks are registered the capability |
| * check is performed. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_setxattr(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| int rc; |
| |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| |
| /* enforce the capability checks at the lsm layer, if needed */ |
| if (!call_int_hook(inode_xattr_skipcap, name)) { |
| rc = cap_inode_setxattr(dentry, name, value, size, flags); |
| if (rc) |
| return rc; |
| } |
| |
| return call_int_hook(inode_setxattr, idmap, dentry, name, value, size, |
| flags); |
| } |
| |
| /** |
| * security_inode_set_acl() - Check if setting posix acls is allowed |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @acl_name: acl name |
| * @kacl: acl struct |
| * |
| * Check permission before setting posix acls, the posix acls in @kacl are |
| * identified by @acl_name. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_set_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name, |
| struct posix_acl *kacl) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_set_acl, idmap, dentry, acl_name, kacl); |
| } |
| |
| /** |
| * security_inode_post_set_acl() - Update inode security from posix acls set |
| * @dentry: file |
| * @acl_name: acl name |
| * @kacl: acl struct |
| * |
| * Update inode security data after successfully setting posix acls on @dentry. |
| * The posix acls in @kacl are identified by @acl_name. |
| */ |
| void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, |
| struct posix_acl *kacl) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return; |
| call_void_hook(inode_post_set_acl, dentry, acl_name, kacl); |
| } |
| |
| /** |
| * security_inode_get_acl() - Check if reading posix acls is allowed |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @acl_name: acl name |
| * |
| * Check permission before getting osix acls, the posix acls are identified by |
| * @acl_name. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_get_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_get_acl, idmap, dentry, acl_name); |
| } |
| |
| /** |
| * security_inode_remove_acl() - Check if removing a posix acl is allowed |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @acl_name: acl name |
| * |
| * Check permission before removing posix acls, the posix acls are identified |
| * by @acl_name. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_remove_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_remove_acl, idmap, dentry, acl_name); |
| } |
| |
| /** |
| * security_inode_post_remove_acl() - Update inode security after rm posix acls |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @acl_name: acl name |
| * |
| * Update inode security data after successfully removing posix acls on |
| * @dentry in @idmap. The posix acls are identified by @acl_name. |
| */ |
| void security_inode_post_remove_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *acl_name) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return; |
| call_void_hook(inode_post_remove_acl, idmap, dentry, acl_name); |
| } |
| |
| /** |
| * security_inode_post_setxattr() - Update the inode after a setxattr operation |
| * @dentry: file |
| * @name: xattr name |
| * @value: xattr value |
| * @size: xattr value size |
| * @flags: flags |
| * |
| * Update inode security field after successful setxattr operation. |
| */ |
| void security_inode_post_setxattr(struct dentry *dentry, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return; |
| call_void_hook(inode_post_setxattr, dentry, name, value, size, flags); |
| } |
| |
| /** |
| * security_inode_getxattr() - Check if xattr access is allowed |
| * @dentry: file |
| * @name: xattr name |
| * |
| * Check permission before obtaining the extended attributes identified by |
| * @name for @dentry. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_getxattr(struct dentry *dentry, const char *name) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_getxattr, dentry, name); |
| } |
| |
| /** |
| * security_inode_listxattr() - Check if listing xattrs is allowed |
| * @dentry: file |
| * |
| * Check permission before obtaining the list of extended attribute names for |
| * @dentry. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_listxattr(struct dentry *dentry) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| return call_int_hook(inode_listxattr, dentry); |
| } |
| |
| /** |
| * security_inode_removexattr() - Check if removing an xattr is allowed |
| * @idmap: idmap of the mount |
| * @dentry: file |
| * @name: xattr name |
| * |
| * This hook performs the desired permission checks before setting the extended |
| * attributes (xattrs) on @dentry. It is important to note that we have some |
| * additional logic before the main LSM implementation calls to detect if we |
| * need to perform an additional capability check at the LSM layer. |
| * |
| * Normally we enforce a capability check prior to executing the various LSM |
| * hook implementations, but if a LSM wants to avoid this capability check, |
| * it can register a 'inode_xattr_skipcap' hook and return a value of 1 for |
| * xattrs that it wants to avoid the capability check, leaving the LSM fully |
| * responsible for enforcing the access control for the specific xattr. If all |
| * of the enabled LSMs refrain from registering a 'inode_xattr_skipcap' hook, |
| * or return a 0 (the default return value), the capability check is still |
| * performed. If no 'inode_xattr_skipcap' hooks are registered the capability |
| * check is performed. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_inode_removexattr(struct mnt_idmap *idmap, |
| struct dentry *dentry, const char *name) |
| { |
| int rc; |
| |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return 0; |
| |
| /* enforce the capability checks at the lsm layer, if needed */ |
| if (!call_int_hook(inode_xattr_skipcap, name)) { |
| rc = cap_inode_removexattr(idmap, dentry, name); |
| if (rc) |
| return rc; |
| } |
| |
| return call_int_hook(inode_removexattr, idmap, dentry, name); |
| } |
| |
| /** |
| * security_inode_post_removexattr() - Update the inode after a removexattr op |
| * @dentry: file |
| * @name: xattr name |
| * |
| * Update the inode after a successful removexattr operation. |
| */ |
| void security_inode_post_removexattr(struct dentry *dentry, const char *name) |
| { |
| if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) |
| return; |
| call_void_hook(inode_post_removexattr, dentry, name); |
| } |
| |
| /** |
| * security_inode_need_killpriv() - Check if security_inode_killpriv() required |
| * @dentry: associated dentry |
| * |
| * Called when an inode has been changed to determine if |
| * security_inode_killpriv() should be called. |
| * |
| * Return: Return <0 on error to abort the inode change operation, return 0 if |
| * security_inode_killpriv() does not need to be called, return >0 if |
| * security_inode_killpriv() does need to be called. |
| */ |
| int security_inode_need_killpriv(struct dentry *dentry) |
| { |
| return call_int_hook(inode_need_killpriv, dentry); |
| } |
| |
| /** |
| * security_inode_killpriv() - The setuid bit is removed, update LSM state |
| * @idmap: idmap of the mount |
| * @dentry: associated dentry |
| * |
| * The @dentry's setuid bit is being removed. Remove similar security labels. |
| * Called with the dentry->d_inode->i_mutex held. |
| * |
| * Return: Return 0 on success. If error is returned, then the operation |
| * causing setuid bit removal is failed. |
| */ |
| int security_inode_killpriv(struct mnt_idmap *idmap, |
| struct dentry *dentry) |
| { |
| return call_int_hook(inode_killpriv, idmap, dentry); |
| } |
| |
| /** |
| * security_inode_getsecurity() - Get the xattr security label of an inode |
| * @idmap: idmap of the mount |
| * @inode: inode |
| * @name: xattr name |
| * @buffer: security label buffer |
| * @alloc: allocation flag |
| * |
| * Retrieve a copy of the extended attribute representation of the security |
| * label associated with @name for @inode via @buffer. Note that @name is the |
| * remainder of the attribute name after the security prefix has been removed. |
| * @alloc is used to specify if the call should return a value via the buffer |
| * or just the value length. |
| * |
| * Return: Returns size of buffer on success. |
| */ |
| int security_inode_getsecurity(struct mnt_idmap *idmap, |
| struct inode *inode, const char *name, |
| void **buffer, bool alloc) |
| { |
| if (unlikely(IS_PRIVATE(inode))) |
| return LSM_RET_DEFAULT(inode_getsecurity); |
| |
| return call_int_hook(inode_getsecurity, idmap, inode, name, buffer, |
| alloc); |
| } |
| |
| /** |
| * security_inode_setsecurity() - Set the xattr security label of an inode |
| * @inode: inode |
| * @name: xattr name |
| * @value: security label |
| * @size: length of security label |
| * @flags: flags |
| * |
| * Set the security label associated with @name for @inode from the extended |
| * attribute value @value. @size indicates the size of the @value in bytes. |
| * @flags may be XATTR_CREATE, XATTR_REPLACE, or 0. Note that @name is the |
| * remainder of the attribute name after the security. prefix has been removed. |
| * |
| * Return: Returns 0 on success. |
| */ |
| int security_inode_setsecurity(struct inode *inode, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| if (unlikely(IS_PRIVATE(inode))) |
| return LSM_RET_DEFAULT(inode_setsecurity); |
| |
| return call_int_hook(inode_setsecurity, inode, name, value, size, |
| flags); |
| } |
| |
| /** |
| * security_inode_listsecurity() - List the xattr security label names |
| * @inode: inode |
| * @buffer: buffer |
| * @buffer_size: size of buffer |
| * |
| * Copy the extended attribute names for the security labels associated with |
| * @inode into @buffer. The maximum size of @buffer is specified by |
| * @buffer_size. @buffer may be NULL to request the size of the buffer |
| * required. |
| * |
| * Return: Returns number of bytes used/required on success. |
| */ |
| int security_inode_listsecurity(struct inode *inode, |
| char *buffer, size_t buffer_size) |
| { |
| if (unlikely(IS_PRIVATE(inode))) |
| return 0; |
| return call_int_hook(inode_listsecurity, inode, buffer, buffer_size); |
| } |
| EXPORT_SYMBOL(security_inode_listsecurity); |
| |
| /** |
| * security_inode_getsecid() - Get an inode's secid |
| * @inode: inode |
| * @secid: secid to return |
| * |
| * Get the secid associated with the node. In case of failure, @secid will be |
| * set to zero. |
| */ |
| void security_inode_getsecid(struct inode *inode, u32 *secid) |
| { |
| call_void_hook(inode_getsecid, inode, secid); |
| } |
| |
| /** |
| * security_inode_copy_up() - Create new creds for an overlayfs copy-up op |
| * @src: union dentry of copy-up file |
| * @new: newly created creds |
| * |
| * A file is about to be copied up from lower layer to upper layer of overlay |
| * filesystem. Security module can prepare a set of new creds and modify as |
| * need be and return new creds. Caller will switch to new creds temporarily to |
| * create new file and release newly allocated creds. |
| * |
| * Return: Returns 0 on success or a negative error code on error. |
| */ |
| int security_inode_copy_up(struct dentry *src, struct cred **new) |
| { |
| return call_int_hook(inode_copy_up, src, new); |
| } |
| EXPORT_SYMBOL(security_inode_copy_up); |
| |
| /** |
| * security_inode_copy_up_xattr() - Filter xattrs in an overlayfs copy-up op |
| * @src: union dentry of copy-up file |
| * @name: xattr name |
| * |
| * Filter the xattrs being copied up when a unioned file is copied up from a |
| * lower layer to the union/overlay layer. The caller is responsible for |
| * reading and writing the xattrs, this hook is merely a filter. |
| * |
| * Return: Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP |
| * if the security module does not know about attribute, or a negative |
| * error code to abort the copy up. |
| */ |
| int security_inode_copy_up_xattr(struct dentry *src, const char *name) |
| { |
| int rc; |
| |
| /* |
| * The implementation can return 0 (accept the xattr), 1 (discard the |
| * xattr), -EOPNOTSUPP if it does not know anything about the xattr or |
| * any other error code in case of an error. |
| */ |
| rc = call_int_hook(inode_copy_up_xattr, src, name); |
| if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr)) |
| return rc; |
| |
| return LSM_RET_DEFAULT(inode_copy_up_xattr); |
| } |
| EXPORT_SYMBOL(security_inode_copy_up_xattr); |
| |
| /** |
| * security_kernfs_init_security() - Init LSM context for a kernfs node |
| * @kn_dir: parent kernfs node |
| * @kn: the kernfs node to initialize |
| * |
| * Initialize the security context of a newly created kernfs node based on its |
| * own and its parent's attributes. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_kernfs_init_security(struct kernfs_node *kn_dir, |
| struct kernfs_node *kn) |
| { |
| return call_int_hook(kernfs_init_security, kn_dir, kn); |
| } |
| |
| /** |
| * security_file_permission() - Check file permissions |
| * @file: file |
| * @mask: requested permissions |
| * |
| * Check file permissions before accessing an open file. This hook is called |
| * by various operations that read or write files. A security module can use |
| * this hook to perform additional checking on these operations, e.g. to |
| * revalidate permissions on use to support privilege bracketing or policy |
| * changes. Notice that this hook is used when the actual read/write |
| * operations are performed, whereas the inode_security_ops hook is called when |
| * a file is opened (as well as many other operations). Although this hook can |
| * be used to revalidate permissions for various system call operations that |
| * read or write files, it does not address the revalidation of permissions for |
| * memory-mapped files. Security modules must handle this separately if they |
| * need such revalidation. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_permission(struct file *file, int mask) |
| { |
| return call_int_hook(file_permission, file, mask); |
| } |
| |
| /** |
| * security_file_alloc() - Allocate and init a file's LSM blob |
| * @file: the file |
| * |
| * Allocate and attach a security structure to the file->f_security field. The |
| * security field is initialized to NULL when the structure is first created. |
| * |
| * Return: Return 0 if the hook is successful and permission is granted. |
| */ |
| int security_file_alloc(struct file *file) |
| { |
| int rc = lsm_file_alloc(file); |
| |
| if (rc) |
| return rc; |
| rc = call_int_hook(file_alloc_security, file); |
| if (unlikely(rc)) |
| security_file_free(file); |
| return rc; |
| } |
| |
| /** |
| * security_file_release() - Perform actions before releasing the file ref |
| * @file: the file |
| * |
| * Perform actions before releasing the last reference to a file. |
| */ |
| void security_file_release(struct file *file) |
| { |
| call_void_hook(file_release, file); |
| } |
| |
| /** |
| * security_file_free() - Free a file's LSM blob |
| * @file: the file |
| * |
| * Deallocate and free any security structures stored in file->f_security. |
| */ |
| void security_file_free(struct file *file) |
| { |
| void *blob; |
| |
| call_void_hook(file_free_security, file); |
| |
| blob = file->f_security; |
| if (blob) { |
| file->f_security = NULL; |
| kmem_cache_free(lsm_file_cache, blob); |
| } |
| } |
| |
| /** |
| * security_file_ioctl() - Check if an ioctl is allowed |
| * @file: associated file |
| * @cmd: ioctl cmd |
| * @arg: ioctl arguments |
| * |
| * Check permission for an ioctl operation on @file. Note that @arg sometimes |
| * represents a user space pointer; in other cases, it may be a simple integer |
| * value. When @arg represents a user space pointer, it should never be used |
| * by the security module. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| { |
| return call_int_hook(file_ioctl, file, cmd, arg); |
| } |
| EXPORT_SYMBOL_GPL(security_file_ioctl); |
| |
| /** |
| * security_file_ioctl_compat() - Check if an ioctl is allowed in compat mode |
| * @file: associated file |
| * @cmd: ioctl cmd |
| * @arg: ioctl arguments |
| * |
| * Compat version of security_file_ioctl() that correctly handles 32-bit |
| * processes running on 64-bit kernels. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_ioctl_compat(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| return call_int_hook(file_ioctl_compat, file, cmd, arg); |
| } |
| EXPORT_SYMBOL_GPL(security_file_ioctl_compat); |
| |
| static inline unsigned long mmap_prot(struct file *file, unsigned long prot) |
| { |
| /* |
| * Does we have PROT_READ and does the application expect |
| * it to imply PROT_EXEC? If not, nothing to talk about... |
| */ |
| if ((prot & (PROT_READ | PROT_EXEC)) != PROT_READ) |
| return prot; |
| if (!(current->personality & READ_IMPLIES_EXEC)) |
| return prot; |
| /* |
| * if that's an anonymous mapping, let it. |
| */ |
| if (!file) |
| return prot | PROT_EXEC; |
| /* |
| * ditto if it's not on noexec mount, except that on !MMU we need |
| * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case |
| */ |
| if (!path_noexec(&file->f_path)) { |
| #ifndef CONFIG_MMU |
| if (file->f_op->mmap_capabilities) { |
| unsigned caps = file->f_op->mmap_capabilities(file); |
| if (!(caps & NOMMU_MAP_EXEC)) |
| return prot; |
| } |
| #endif |
| return prot | PROT_EXEC; |
| } |
| /* anything on noexec mount won't get PROT_EXEC */ |
| return prot; |
| } |
| |
| /** |
| * security_mmap_file() - Check if mmap'ing a file is allowed |
| * @file: file |
| * @prot: protection applied by the kernel |
| * @flags: flags |
| * |
| * Check permissions for a mmap operation. The @file may be NULL, e.g. if |
| * mapping anonymous memory. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_mmap_file(struct file *file, unsigned long prot, |
| unsigned long flags) |
| { |
| return call_int_hook(mmap_file, file, prot, mmap_prot(file, prot), |
| flags); |
| } |
| |
| /** |
| * security_mmap_addr() - Check if mmap'ing an address is allowed |
| * @addr: address |
| * |
| * Check permissions for a mmap operation at @addr. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_mmap_addr(unsigned long addr) |
| { |
| return call_int_hook(mmap_addr, addr); |
| } |
| |
| /** |
| * security_file_mprotect() - Check if changing memory protections is allowed |
| * @vma: memory region |
| * @reqprot: application requested protection |
| * @prot: protection applied by the kernel |
| * |
| * Check permissions before changing memory access permissions. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, |
| unsigned long prot) |
| { |
| return call_int_hook(file_mprotect, vma, reqprot, prot); |
| } |
| |
| /** |
| * security_file_lock() - Check if a file lock is allowed |
| * @file: file |
| * @cmd: lock operation (e.g. F_RDLCK, F_WRLCK) |
| * |
| * Check permission before performing file locking operations. Note the hook |
| * mediates both flock and fcntl style locks. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_lock(struct file *file, unsigned int cmd) |
| { |
| return call_int_hook(file_lock, file, cmd); |
| } |
| |
| /** |
| * security_file_fcntl() - Check if fcntl() op is allowed |
| * @file: file |
| * @cmd: fcntl command |
| * @arg: command argument |
| * |
| * Check permission before allowing the file operation specified by @cmd from |
| * being performed on the file @file. Note that @arg sometimes represents a |
| * user space pointer; in other cases, it may be a simple integer value. When |
| * @arg represents a user space pointer, it should never be used by the |
| * security module. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) |
| { |
| return call_int_hook(file_fcntl, file, cmd, arg); |
| } |
| |
| /** |
| * security_file_set_fowner() - Set the file owner info in the LSM blob |
| * @file: the file |
| * |
| * Save owner security information (typically from current->security) in |
| * file->f_security for later use by the send_sigiotask hook. |
| * |
| * Return: Returns 0 on success. |
| */ |
| void security_file_set_fowner(struct file *file) |
| { |
| call_void_hook(file_set_fowner, file); |
| } |
| |
| /** |
| * security_file_send_sigiotask() - Check if sending SIGIO/SIGURG is allowed |
| * @tsk: target task |
| * @fown: signal sender |
| * @sig: signal to be sent, SIGIO is sent if 0 |
| * |
| * Check permission for the file owner @fown to send SIGIO or SIGURG to the |
| * process @tsk. Note that this hook is sometimes called from interrupt. Note |
| * that the fown_struct, @fown, is never outside the context of a struct file, |
| * so the file structure (and associated security information) can always be |
| * obtained: container_of(fown, struct file, f_owner). |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_send_sigiotask(struct task_struct *tsk, |
| struct fown_struct *fown, int sig) |
| { |
| return call_int_hook(file_send_sigiotask, tsk, fown, sig); |
| } |
| |
| /** |
| * security_file_receive() - Check if receiving a file via IPC is allowed |
| * @file: file being received |
| * |
| * This hook allows security modules to control the ability of a process to |
| * receive an open file descriptor via socket IPC. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_receive(struct file *file) |
| { |
| return call_int_hook(file_receive, file); |
| } |
| |
| /** |
| * security_file_open() - Save open() time state for late use by the LSM |
| * @file: |
| * |
| * Save open-time permission checking state for later use upon file_permission, |
| * and recheck access if anything has changed since inode_permission. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_open(struct file *file) |
| { |
| int ret; |
| |
| ret = call_int_hook(file_open, file); |
| if (ret) |
| return ret; |
| |
| return fsnotify_open_perm(file); |
| } |
| |
| /** |
| * security_file_post_open() - Evaluate a file after it has been opened |
| * @file: the file |
| * @mask: access mask |
| * |
| * Evaluate an opened file and the access mask requested with open(). The hook |
| * is useful for LSMs that require the file content to be available in order to |
| * make decisions. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_post_open(struct file *file, int mask) |
| { |
| return call_int_hook(file_post_open, file, mask); |
| } |
| EXPORT_SYMBOL_GPL(security_file_post_open); |
| |
| /** |
| * security_file_truncate() - Check if truncating a file is allowed |
| * @file: file |
| * |
| * Check permission before truncating a file, i.e. using ftruncate. Note that |
| * truncation permission may also be checked based on the path, using the |
| * @path_truncate hook. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_file_truncate(struct file *file) |
| { |
| return call_int_hook(file_truncate, file); |
| } |
| |
| /** |
| * security_task_alloc() - Allocate a task's LSM blob |
| * @task: the task |
| * @clone_flags: flags indicating what is being shared |
| * |
| * Handle allocation of task-related resources. |
| * |
| * Return: Returns a zero on success, negative values on failure. |
| */ |
| int security_task_alloc(struct task_struct *task, unsigned long clone_flags) |
| { |
| int rc = lsm_task_alloc(task); |
| |
| if (rc) |
| return rc; |
| rc = call_int_hook(task_alloc, task, clone_flags); |
| if (unlikely(rc)) |
| security_task_free(task); |
| return rc; |
| } |
| |
| /** |
| * security_task_free() - Free a task's LSM blob and related resources |
| * @task: task |
| * |
| * Handle release of task-related resources. Note that this can be called from |
| * interrupt context. |
| */ |
| void security_task_free(struct task_struct *task) |
| { |
| call_void_hook(task_free, task); |
| |
| kfree(task->security); |
| task->security = NULL; |
| } |
| |
| /** |
| * security_cred_alloc_blank() - Allocate the min memory to allow cred_transfer |
| * @cred: credentials |
| * @gfp: gfp flags |
| * |
| * Only allocate sufficient memory and attach to @cred such that |
| * cred_transfer() will not get ENOMEM. |
| * |
| * Return: Returns 0 on success, negative values on failure. |
| */ |
| int security_cred_alloc_blank(struct cred *cred, gfp_t gfp) |
| { |
| int rc = lsm_cred_alloc(cred, gfp); |
| |
| if (rc) |
| return rc; |
| |
| rc = call_int_hook(cred_alloc_blank, cred, gfp); |
| if (unlikely(rc)) |
| security_cred_free(cred); |
| return rc; |
| } |
| |
| /** |
| * security_cred_free() - Free the cred's LSM blob and associated resources |
| * @cred: credentials |
| * |
| * Deallocate and clear the cred->security field in a set of credentials. |
| */ |
| void security_cred_free(struct cred *cred) |
| { |
| /* |
| * There is a failure case in prepare_creds() that |
| * may result in a call here with ->security being NULL. |
| */ |
| if (unlikely(cred->security == NULL)) |
| return; |
| |
| call_void_hook(cred_free, cred); |
| |
| kfree(cred->security); |
| cred->security = NULL; |
| } |
| |
| /** |
| * security_prepare_creds() - Prepare a new set of credentials |
| * @new: new credentials |
| * @old: original credentials |
| * @gfp: gfp flags |
| * |
| * Prepare a new set of credentials by copying the data from the old set. |
| * |
| * Return: Returns 0 on success, negative values on failure. |
| */ |
| int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp) |
| { |
| int rc = lsm_cred_alloc(new, gfp); |
| |
| if (rc) |
| return rc; |
| |
| rc = call_int_hook(cred_prepare, new, old, gfp); |
| if (unlikely(rc)) |
| security_cred_free(new); |
| return rc; |
| } |
| |
| /** |
| * security_transfer_creds() - Transfer creds |
| * @new: target credentials |
| * @old: original credentials |
| * |
| * Transfer data from original creds to new creds. |
| */ |
| void security_transfer_creds(struct cred *new, const struct cred *old) |
| { |
| call_void_hook(cred_transfer, new, old); |
| } |
| |
| /** |
| * security_cred_getsecid() - Get the secid from a set of credentials |
| * @c: credentials |
| * @secid: secid value |
| * |
| * Retrieve the security identifier of the cred structure @c. In case of |
| * failure, @secid will be set to zero. |
| */ |
| void security_cred_getsecid(const struct cred *c, u32 *secid) |
| { |
| *secid = 0; |
| call_void_hook(cred_getsecid, c, secid); |
| } |
| EXPORT_SYMBOL(security_cred_getsecid); |
| |
| /** |
| * security_kernel_act_as() - Set the kernel credentials to act as secid |
| * @new: credentials |
| * @secid: secid |
| * |
| * Set the credentials for a kernel service to act as (subjective context). |
| * The current task must be the one that nominated @secid. |
| * |
| * Return: Returns 0 if successful. |
| */ |
| int security_kernel_act_as(struct cred *new, u32 secid) |
| { |
| return call_int_hook(kernel_act_as, new, secid); |
| } |
| |
| /** |
| * security_kernel_create_files_as() - Set file creation context using an inode |
| * @new: target credentials |
| * @inode: reference inode |
| * |
| * Set the file creation context in a set of credentials to be the same as the |
| * objective context of the specified inode. The current task must be the one |
| * that nominated @inode. |
| * |
| * Return: Returns 0 if successful. |
| */ |
| int security_kernel_create_files_as(struct cred *new, struct inode *inode) |
| { |
| return call_int_hook(kernel_create_files_as, new, inode); |
| } |
| |
| /** |
| * security_kernel_module_request() - Check if loading a module is allowed |
| * @kmod_name: module name |
| * |
| * Ability to trigger the kernel to automatically upcall to userspace for |
| * userspace to load a kernel module with the given name. |
| * |
| * Return: Returns 0 if successful. |
| */ |
| int security_kernel_module_request(char *kmod_name) |
| { |
| return call_int_hook(kernel_module_request, kmod_name); |
| } |
| |
| /** |
| * security_kernel_read_file() - Read a file specified by userspace |
| * @file: file |
| * @id: file identifier |
| * @contents: trust if security_kernel_post_read_file() will be called |
| * |
| * Read a file specified by userspace. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_kernel_read_file(struct file *file, enum kernel_read_file_id id, |
| bool contents) |
| { |
| return call_int_hook(kernel_read_file, file, id, contents); |
| } |
| EXPORT_SYMBOL_GPL(security_kernel_read_file); |
| |
| /** |
| * security_kernel_post_read_file() - Read a file specified by userspace |
| * @file: file |
| * @buf: file contents |
| * @size: size of file contents |
| * @id: file identifier |
| * |
| * Read a file specified by userspace. This must be paired with a prior call |
| * to security_kernel_read_file() call that indicated this hook would also be |
| * called, see security_kernel_read_file() for more information. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_kernel_post_read_file(struct file *file, char *buf, loff_t size, |
| enum kernel_read_file_id id) |
| { |
| return call_int_hook(kernel_post_read_file, file, buf, size, id); |
| } |
| EXPORT_SYMBOL_GPL(security_kernel_post_read_file); |
| |
| /** |
| * security_kernel_load_data() - Load data provided by userspace |
| * @id: data identifier |
| * @contents: true if security_kernel_post_load_data() will be called |
| * |
| * Load data provided by userspace. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_kernel_load_data(enum kernel_load_data_id id, bool contents) |
| { |
| return call_int_hook(kernel_load_data, id, contents); |
| } |
| EXPORT_SYMBOL_GPL(security_kernel_load_data); |
| |
| /** |
| * security_kernel_post_load_data() - Load userspace data from a non-file source |
| * @buf: data |
| * @size: size of data |
| * @id: data identifier |
| * @description: text description of data, specific to the id value |
| * |
| * Load data provided by a non-file source (usually userspace buffer). This |
| * must be paired with a prior security_kernel_load_data() call that indicated |
| * this hook would also be called, see security_kernel_load_data() for more |
| * information. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_kernel_post_load_data(char *buf, loff_t size, |
| enum kernel_load_data_id id, |
| char *description) |
| { |
| return call_int_hook(kernel_post_load_data, buf, size, id, description); |
| } |
| EXPORT_SYMBOL_GPL(security_kernel_post_load_data); |
| |
| /** |
| * security_task_fix_setuid() - Update LSM with new user id attributes |
| * @new: updated credentials |
| * @old: credentials being replaced |
| * @flags: LSM_SETID_* flag values |
| * |
| * Update the module's state after setting one or more of the user identity |
| * attributes of the current process. The @flags parameter indicates which of |
| * the set*uid system calls invoked this hook. If @new is the set of |
| * credentials that will be installed. Modifications should be made to this |
| * rather than to @current->cred. |
| * |
| * Return: Returns 0 on success. |
| */ |
| int security_task_fix_setuid(struct cred *new, const struct cred *old, |
| int flags) |
| { |
| return call_int_hook(task_fix_setuid, new, old, flags); |
| } |
| |
| /** |
| * security_task_fix_setgid() - Update LSM with new group id attributes |
| * @new: updated credentials |
| * @old: credentials being replaced |
| * @flags: LSM_SETID_* flag value |
| * |
| * Update the module's state after setting one or more of the group identity |
| * attributes of the current process. The @flags parameter indicates which of |
| * the set*gid system calls invoked this hook. @new is the set of credentials |
| * that will be installed. Modifications should be made to this rather than to |
| * @current->cred. |
| * |
| * Return: Returns 0 on success. |
| */ |
| int security_task_fix_setgid(struct cred *new, const struct cred *old, |
| int flags) |
| { |
| return call_int_hook(task_fix_setgid, new, old, flags); |
| } |
| |
| /** |
| * security_task_fix_setgroups() - Update LSM with new supplementary groups |
| * @new: updated credentials |
| * @old: credentials being replaced |
| * |
| * Update the module's state after setting the supplementary group identity |
| * attributes of the current process. @new is the set of credentials that will |
| * be installed. Modifications should be made to this rather than to |
| * @current->cred. |
| * |
| * Return: Returns 0 on success. |
| */ |
| int security_task_fix_setgroups(struct cred *new, const struct cred *old) |
| { |
| return call_int_hook(task_fix_setgroups, new, old); |
| } |
| |
| /** |
| * security_task_setpgid() - Check if setting the pgid is allowed |
| * @p: task being modified |
| * @pgid: new pgid |
| * |
| * Check permission before setting the process group identifier of the process |
| * @p to @pgid. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_setpgid(struct task_struct *p, pid_t pgid) |
| { |
| return call_int_hook(task_setpgid, p, pgid); |
| } |
| |
| /** |
| * security_task_getpgid() - Check if getting the pgid is allowed |
| * @p: task |
| * |
| * Check permission before getting the process group identifier of the process |
| * @p. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_getpgid(struct task_struct *p) |
| { |
| return call_int_hook(task_getpgid, p); |
| } |
| |
| /** |
| * security_task_getsid() - Check if getting the session id is allowed |
| * @p: task |
| * |
| * Check permission before getting the session identifier of the process @p. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_getsid(struct task_struct *p) |
| { |
| return call_int_hook(task_getsid, p); |
| } |
| |
| /** |
| * security_current_getsecid_subj() - Get the current task's subjective secid |
| * @secid: secid value |
| * |
| * Retrieve the subjective security identifier of the current task and return |
| * it in @secid. In case of failure, @secid will be set to zero. |
| */ |
| void security_current_getsecid_subj(u32 *secid) |
| { |
| *secid = 0; |
| call_void_hook(current_getsecid_subj, secid); |
| } |
| EXPORT_SYMBOL(security_current_getsecid_subj); |
| |
| /** |
| * security_task_getsecid_obj() - Get a task's objective secid |
| * @p: target task |
| * @secid: secid value |
| * |
| * Retrieve the objective security identifier of the task_struct in @p and |
| * return it in @secid. In case of failure, @secid will be set to zero. |
| */ |
| void security_task_getsecid_obj(struct task_struct *p, u32 *secid) |
| { |
| *secid = 0; |
| call_void_hook(task_getsecid_obj, p, secid); |
| } |
| EXPORT_SYMBOL(security_task_getsecid_obj); |
| |
| /** |
| * security_task_setnice() - Check if setting a task's nice value is allowed |
| * @p: target task |
| * @nice: nice value |
| * |
| * Check permission before setting the nice value of @p to @nice. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_setnice(struct task_struct *p, int nice) |
| { |
| return call_int_hook(task_setnice, p, nice); |
| } |
| |
| /** |
| * security_task_setioprio() - Check if setting a task's ioprio is allowed |
| * @p: target task |
| * @ioprio: ioprio value |
| * |
| * Check permission before setting the ioprio value of @p to @ioprio. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_setioprio(struct task_struct *p, int ioprio) |
| { |
| return call_int_hook(task_setioprio, p, ioprio); |
| } |
| |
| /** |
| * security_task_getioprio() - Check if getting a task's ioprio is allowed |
| * @p: task |
| * |
| * Check permission before getting the ioprio value of @p. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_getioprio(struct task_struct *p) |
| { |
| return call_int_hook(task_getioprio, p); |
| } |
| |
| /** |
| * security_task_prlimit() - Check if get/setting resources limits is allowed |
| * @cred: current task credentials |
| * @tcred: target task credentials |
| * @flags: LSM_PRLIMIT_* flag bits indicating a get/set/both |
| * |
| * Check permission before getting and/or setting the resource limits of |
| * another task. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_prlimit(const struct cred *cred, const struct cred *tcred, |
| unsigned int flags) |
| { |
| return call_int_hook(task_prlimit, cred, tcred, flags); |
| } |
| |
| /** |
| * security_task_setrlimit() - Check if setting a new rlimit value is allowed |
| * @p: target task's group leader |
| * @resource: resource whose limit is being set |
| * @new_rlim: new resource limit |
| * |
| * Check permission before setting the resource limits of process @p for |
| * @resource to @new_rlim. The old resource limit values can be examined by |
| * dereferencing (p->signal->rlim + resource). |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_setrlimit(struct task_struct *p, unsigned int resource, |
| struct rlimit *new_rlim) |
| { |
| return call_int_hook(task_setrlimit, p, resource, new_rlim); |
| } |
| |
| /** |
| * security_task_setscheduler() - Check if setting sched policy/param is allowed |
| * @p: target task |
| * |
| * Check permission before setting scheduling policy and/or parameters of |
| * process @p. |
| * |
| * Return: Returns 0 if permission is granted. |
| */ |
| int security_task_setscheduler(struct task_struct *p) |
| { |
| return call_int_hook |