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-rw-r--r--security/tomoyo/domain.c945
1 files changed, 945 insertions, 0 deletions
diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c
new file mode 100644
index 000000000..31af29f66
--- /dev/null
+++ b/security/tomoyo/domain.c
@@ -0,0 +1,945 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * security/tomoyo/domain.c
+ *
+ * Copyright (C) 2005-2011 NTT DATA CORPORATION
+ */
+
+#include "common.h"
+
+#include <linux/binfmts.h>
+#include <linux/slab.h>
+#include <linux/rculist.h>
+
+/* Variables definitions.*/
+
+/* The initial domain. */
+struct tomoyo_domain_info tomoyo_kernel_domain;
+
+/**
+ * tomoyo_update_policy - Update an entry for exception policy.
+ *
+ * @new_entry: Pointer to "struct tomoyo_acl_info".
+ * @size: Size of @new_entry in bytes.
+ * @param: Pointer to "struct tomoyo_acl_param".
+ * @check_duplicate: Callback function to find duplicated entry.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+int tomoyo_update_policy(struct tomoyo_acl_head *new_entry, const int size,
+ struct tomoyo_acl_param *param,
+ bool (*check_duplicate)(const struct tomoyo_acl_head
+ *,
+ const struct tomoyo_acl_head
+ *))
+{
+ int error = param->is_delete ? -ENOENT : -ENOMEM;
+ struct tomoyo_acl_head *entry;
+ struct list_head *list = param->list;
+
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ return -ENOMEM;
+ list_for_each_entry_rcu(entry, list, list,
+ srcu_read_lock_held(&tomoyo_ss)) {
+ if (entry->is_deleted == TOMOYO_GC_IN_PROGRESS)
+ continue;
+ if (!check_duplicate(entry, new_entry))
+ continue;
+ entry->is_deleted = param->is_delete;
+ error = 0;
+ break;
+ }
+ if (error && !param->is_delete) {
+ entry = tomoyo_commit_ok(new_entry, size);
+ if (entry) {
+ list_add_tail_rcu(&entry->list, list);
+ error = 0;
+ }
+ }
+ mutex_unlock(&tomoyo_policy_lock);
+ return error;
+}
+
+/**
+ * tomoyo_same_acl_head - Check for duplicated "struct tomoyo_acl_info" entry.
+ *
+ * @a: Pointer to "struct tomoyo_acl_info".
+ * @b: Pointer to "struct tomoyo_acl_info".
+ *
+ * Returns true if @a == @b, false otherwise.
+ */
+static inline bool tomoyo_same_acl_head(const struct tomoyo_acl_info *a,
+ const struct tomoyo_acl_info *b)
+{
+ return a->type == b->type && a->cond == b->cond;
+}
+
+/**
+ * tomoyo_update_domain - Update an entry for domain policy.
+ *
+ * @new_entry: Pointer to "struct tomoyo_acl_info".
+ * @size: Size of @new_entry in bytes.
+ * @param: Pointer to "struct tomoyo_acl_param".
+ * @check_duplicate: Callback function to find duplicated entry.
+ * @merge_duplicate: Callback function to merge duplicated entry.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+int tomoyo_update_domain(struct tomoyo_acl_info *new_entry, const int size,
+ struct tomoyo_acl_param *param,
+ bool (*check_duplicate)(const struct tomoyo_acl_info
+ *,
+ const struct tomoyo_acl_info
+ *),
+ bool (*merge_duplicate)(struct tomoyo_acl_info *,
+ struct tomoyo_acl_info *,
+ const bool))
+{
+ const bool is_delete = param->is_delete;
+ int error = is_delete ? -ENOENT : -ENOMEM;
+ struct tomoyo_acl_info *entry;
+ struct list_head * const list = param->list;
+
+ if (param->data[0]) {
+ new_entry->cond = tomoyo_get_condition(param);
+ if (!new_entry->cond)
+ return -EINVAL;
+ /*
+ * Domain transition preference is allowed for only
+ * "file execute" entries.
+ */
+ if (new_entry->cond->transit &&
+ !(new_entry->type == TOMOYO_TYPE_PATH_ACL &&
+ container_of(new_entry, struct tomoyo_path_acl, head)
+ ->perm == 1 << TOMOYO_TYPE_EXECUTE))
+ goto out;
+ }
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ goto out;
+ list_for_each_entry_rcu(entry, list, list,
+ srcu_read_lock_held(&tomoyo_ss)) {
+ if (entry->is_deleted == TOMOYO_GC_IN_PROGRESS)
+ continue;
+ if (!tomoyo_same_acl_head(entry, new_entry) ||
+ !check_duplicate(entry, new_entry))
+ continue;
+ if (merge_duplicate)
+ entry->is_deleted = merge_duplicate(entry, new_entry,
+ is_delete);
+ else
+ entry->is_deleted = is_delete;
+ error = 0;
+ break;
+ }
+ if (error && !is_delete) {
+ entry = tomoyo_commit_ok(new_entry, size);
+ if (entry) {
+ list_add_tail_rcu(&entry->list, list);
+ error = 0;
+ }
+ }
+ mutex_unlock(&tomoyo_policy_lock);
+out:
+ tomoyo_put_condition(new_entry->cond);
+ return error;
+}
+
+/**
+ * tomoyo_check_acl - Do permission check.
+ *
+ * @r: Pointer to "struct tomoyo_request_info".
+ * @check_entry: Callback function to check type specific parameters.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+void tomoyo_check_acl(struct tomoyo_request_info *r,
+ bool (*check_entry)(struct tomoyo_request_info *,
+ const struct tomoyo_acl_info *))
+{
+ const struct tomoyo_domain_info *domain = r->domain;
+ struct tomoyo_acl_info *ptr;
+ const struct list_head *list = &domain->acl_info_list;
+ u16 i = 0;
+
+retry:
+ list_for_each_entry_rcu(ptr, list, list,
+ srcu_read_lock_held(&tomoyo_ss)) {
+ if (ptr->is_deleted || ptr->type != r->param_type)
+ continue;
+ if (!check_entry(r, ptr))
+ continue;
+ if (!tomoyo_condition(r, ptr->cond))
+ continue;
+ r->matched_acl = ptr;
+ r->granted = true;
+ return;
+ }
+ for (; i < TOMOYO_MAX_ACL_GROUPS; i++) {
+ if (!test_bit(i, domain->group))
+ continue;
+ list = &domain->ns->acl_group[i++];
+ goto retry;
+ }
+ r->granted = false;
+}
+
+/* The list for "struct tomoyo_domain_info". */
+LIST_HEAD(tomoyo_domain_list);
+
+/**
+ * tomoyo_last_word - Get last component of a domainname.
+ *
+ * @name: Domainname to check.
+ *
+ * Returns the last word of @domainname.
+ */
+static const char *tomoyo_last_word(const char *name)
+{
+ const char *cp = strrchr(name, ' ');
+
+ if (cp)
+ return cp + 1;
+ return name;
+}
+
+/**
+ * tomoyo_same_transition_control - Check for duplicated "struct tomoyo_transition_control" entry.
+ *
+ * @a: Pointer to "struct tomoyo_acl_head".
+ * @b: Pointer to "struct tomoyo_acl_head".
+ *
+ * Returns true if @a == @b, false otherwise.
+ */
+static bool tomoyo_same_transition_control(const struct tomoyo_acl_head *a,
+ const struct tomoyo_acl_head *b)
+{
+ const struct tomoyo_transition_control *p1 = container_of(a,
+ typeof(*p1),
+ head);
+ const struct tomoyo_transition_control *p2 = container_of(b,
+ typeof(*p2),
+ head);
+
+ return p1->type == p2->type && p1->is_last_name == p2->is_last_name
+ && p1->domainname == p2->domainname
+ && p1->program == p2->program;
+}
+
+/**
+ * tomoyo_write_transition_control - Write "struct tomoyo_transition_control" list.
+ *
+ * @param: Pointer to "struct tomoyo_acl_param".
+ * @type: Type of this entry.
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+int tomoyo_write_transition_control(struct tomoyo_acl_param *param,
+ const u8 type)
+{
+ struct tomoyo_transition_control e = { .type = type };
+ int error = param->is_delete ? -ENOENT : -ENOMEM;
+ char *program = param->data;
+ char *domainname = strstr(program, " from ");
+
+ if (domainname) {
+ *domainname = '\0';
+ domainname += 6;
+ } else if (type == TOMOYO_TRANSITION_CONTROL_NO_KEEP ||
+ type == TOMOYO_TRANSITION_CONTROL_KEEP) {
+ domainname = program;
+ program = NULL;
+ }
+ if (program && strcmp(program, "any")) {
+ if (!tomoyo_correct_path(program))
+ return -EINVAL;
+ e.program = tomoyo_get_name(program);
+ if (!e.program)
+ goto out;
+ }
+ if (domainname && strcmp(domainname, "any")) {
+ if (!tomoyo_correct_domain(domainname)) {
+ if (!tomoyo_correct_path(domainname))
+ goto out;
+ e.is_last_name = true;
+ }
+ e.domainname = tomoyo_get_name(domainname);
+ if (!e.domainname)
+ goto out;
+ }
+ param->list = &param->ns->policy_list[TOMOYO_ID_TRANSITION_CONTROL];
+ error = tomoyo_update_policy(&e.head, sizeof(e), param,
+ tomoyo_same_transition_control);
+out:
+ tomoyo_put_name(e.domainname);
+ tomoyo_put_name(e.program);
+ return error;
+}
+
+/**
+ * tomoyo_scan_transition - Try to find specific domain transition type.
+ *
+ * @list: Pointer to "struct list_head".
+ * @domainname: The name of current domain.
+ * @program: The name of requested program.
+ * @last_name: The last component of @domainname.
+ * @type: One of values in "enum tomoyo_transition_type".
+ *
+ * Returns true if found one, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+static inline bool tomoyo_scan_transition
+(const struct list_head *list, const struct tomoyo_path_info *domainname,
+ const struct tomoyo_path_info *program, const char *last_name,
+ const enum tomoyo_transition_type type)
+{
+ const struct tomoyo_transition_control *ptr;
+
+ list_for_each_entry_rcu(ptr, list, head.list,
+ srcu_read_lock_held(&tomoyo_ss)) {
+ if (ptr->head.is_deleted || ptr->type != type)
+ continue;
+ if (ptr->domainname) {
+ if (!ptr->is_last_name) {
+ if (ptr->domainname != domainname)
+ continue;
+ } else {
+ /*
+ * Use direct strcmp() since this is
+ * unlikely used.
+ */
+ if (strcmp(ptr->domainname->name, last_name))
+ continue;
+ }
+ }
+ if (ptr->program && tomoyo_pathcmp(ptr->program, program))
+ continue;
+ return true;
+ }
+ return false;
+}
+
+/**
+ * tomoyo_transition_type - Get domain transition type.
+ *
+ * @ns: Pointer to "struct tomoyo_policy_namespace".
+ * @domainname: The name of current domain.
+ * @program: The name of requested program.
+ *
+ * Returns TOMOYO_TRANSITION_CONTROL_TRANSIT if executing @program causes
+ * domain transition across namespaces, TOMOYO_TRANSITION_CONTROL_INITIALIZE if
+ * executing @program reinitializes domain transition within that namespace,
+ * TOMOYO_TRANSITION_CONTROL_KEEP if executing @program stays at @domainname ,
+ * others otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+static enum tomoyo_transition_type tomoyo_transition_type
+(const struct tomoyo_policy_namespace *ns,
+ const struct tomoyo_path_info *domainname,
+ const struct tomoyo_path_info *program)
+{
+ const char *last_name = tomoyo_last_word(domainname->name);
+ enum tomoyo_transition_type type = TOMOYO_TRANSITION_CONTROL_NO_RESET;
+
+ while (type < TOMOYO_MAX_TRANSITION_TYPE) {
+ const struct list_head * const list =
+ &ns->policy_list[TOMOYO_ID_TRANSITION_CONTROL];
+
+ if (!tomoyo_scan_transition(list, domainname, program,
+ last_name, type)) {
+ type++;
+ continue;
+ }
+ if (type != TOMOYO_TRANSITION_CONTROL_NO_RESET &&
+ type != TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE)
+ break;
+ /*
+ * Do not check for reset_domain if no_reset_domain matched.
+ * Do not check for initialize_domain if no_initialize_domain
+ * matched.
+ */
+ type++;
+ type++;
+ }
+ return type;
+}
+
+/**
+ * tomoyo_same_aggregator - Check for duplicated "struct tomoyo_aggregator" entry.
+ *
+ * @a: Pointer to "struct tomoyo_acl_head".
+ * @b: Pointer to "struct tomoyo_acl_head".
+ *
+ * Returns true if @a == @b, false otherwise.
+ */
+static bool tomoyo_same_aggregator(const struct tomoyo_acl_head *a,
+ const struct tomoyo_acl_head *b)
+{
+ const struct tomoyo_aggregator *p1 = container_of(a, typeof(*p1),
+ head);
+ const struct tomoyo_aggregator *p2 = container_of(b, typeof(*p2),
+ head);
+
+ return p1->original_name == p2->original_name &&
+ p1->aggregated_name == p2->aggregated_name;
+}
+
+/**
+ * tomoyo_write_aggregator - Write "struct tomoyo_aggregator" list.
+ *
+ * @param: Pointer to "struct tomoyo_acl_param".
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+int tomoyo_write_aggregator(struct tomoyo_acl_param *param)
+{
+ struct tomoyo_aggregator e = { };
+ int error = param->is_delete ? -ENOENT : -ENOMEM;
+ const char *original_name = tomoyo_read_token(param);
+ const char *aggregated_name = tomoyo_read_token(param);
+
+ if (!tomoyo_correct_word(original_name) ||
+ !tomoyo_correct_path(aggregated_name))
+ return -EINVAL;
+ e.original_name = tomoyo_get_name(original_name);
+ e.aggregated_name = tomoyo_get_name(aggregated_name);
+ if (!e.original_name || !e.aggregated_name ||
+ e.aggregated_name->is_patterned) /* No patterns allowed. */
+ goto out;
+ param->list = &param->ns->policy_list[TOMOYO_ID_AGGREGATOR];
+ error = tomoyo_update_policy(&e.head, sizeof(e), param,
+ tomoyo_same_aggregator);
+out:
+ tomoyo_put_name(e.original_name);
+ tomoyo_put_name(e.aggregated_name);
+ return error;
+}
+
+/**
+ * tomoyo_find_namespace - Find specified namespace.
+ *
+ * @name: Name of namespace to find.
+ * @len: Length of @name.
+ *
+ * Returns pointer to "struct tomoyo_policy_namespace" if found,
+ * NULL otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+static struct tomoyo_policy_namespace *tomoyo_find_namespace
+(const char *name, const unsigned int len)
+{
+ struct tomoyo_policy_namespace *ns;
+
+ list_for_each_entry(ns, &tomoyo_namespace_list, namespace_list) {
+ if (strncmp(name, ns->name, len) ||
+ (name[len] && name[len] != ' '))
+ continue;
+ return ns;
+ }
+ return NULL;
+}
+
+/**
+ * tomoyo_assign_namespace - Create a new namespace.
+ *
+ * @domainname: Name of namespace to create.
+ *
+ * Returns pointer to "struct tomoyo_policy_namespace" on success,
+ * NULL otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+struct tomoyo_policy_namespace *tomoyo_assign_namespace(const char *domainname)
+{
+ struct tomoyo_policy_namespace *ptr;
+ struct tomoyo_policy_namespace *entry;
+ const char *cp = domainname;
+ unsigned int len = 0;
+
+ while (*cp && *cp++ != ' ')
+ len++;
+ ptr = tomoyo_find_namespace(domainname, len);
+ if (ptr)
+ return ptr;
+ if (len >= TOMOYO_EXEC_TMPSIZE - 10 || !tomoyo_domain_def(domainname))
+ return NULL;
+ entry = kzalloc(sizeof(*entry) + len + 1, GFP_NOFS | __GFP_NOWARN);
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ goto out;
+ ptr = tomoyo_find_namespace(domainname, len);
+ if (!ptr && tomoyo_memory_ok(entry)) {
+ char *name = (char *) (entry + 1);
+
+ ptr = entry;
+ memmove(name, domainname, len);
+ name[len] = '\0';
+ entry->name = name;
+ tomoyo_init_policy_namespace(entry);
+ entry = NULL;
+ }
+ mutex_unlock(&tomoyo_policy_lock);
+out:
+ kfree(entry);
+ return ptr;
+}
+
+/**
+ * tomoyo_namespace_jump - Check for namespace jump.
+ *
+ * @domainname: Name of domain.
+ *
+ * Returns true if namespace differs, false otherwise.
+ */
+static bool tomoyo_namespace_jump(const char *domainname)
+{
+ const char *namespace = tomoyo_current_namespace()->name;
+ const int len = strlen(namespace);
+
+ return strncmp(domainname, namespace, len) ||
+ (domainname[len] && domainname[len] != ' ');
+}
+
+/**
+ * tomoyo_assign_domain - Create a domain or a namespace.
+ *
+ * @domainname: The name of domain.
+ * @transit: True if transit to domain found or created.
+ *
+ * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+struct tomoyo_domain_info *tomoyo_assign_domain(const char *domainname,
+ const bool transit)
+{
+ struct tomoyo_domain_info e = { };
+ struct tomoyo_domain_info *entry = tomoyo_find_domain(domainname);
+ bool created = false;
+
+ if (entry) {
+ if (transit) {
+ /*
+ * Since namespace is created at runtime, profiles may
+ * not be created by the moment the process transits to
+ * that domain. Do not perform domain transition if
+ * profile for that domain is not yet created.
+ */
+ if (tomoyo_policy_loaded &&
+ !entry->ns->profile_ptr[entry->profile])
+ return NULL;
+ }
+ return entry;
+ }
+ /* Requested domain does not exist. */
+ /* Don't create requested domain if domainname is invalid. */
+ if (strlen(domainname) >= TOMOYO_EXEC_TMPSIZE - 10 ||
+ !tomoyo_correct_domain(domainname))
+ return NULL;
+ /*
+ * Since definition of profiles and acl_groups may differ across
+ * namespaces, do not inherit "use_profile" and "use_group" settings
+ * by automatically creating requested domain upon domain transition.
+ */
+ if (transit && tomoyo_namespace_jump(domainname))
+ return NULL;
+ e.ns = tomoyo_assign_namespace(domainname);
+ if (!e.ns)
+ return NULL;
+ /*
+ * "use_profile" and "use_group" settings for automatically created
+ * domains are inherited from current domain. These are 0 for manually
+ * created domains.
+ */
+ if (transit) {
+ const struct tomoyo_domain_info *domain = tomoyo_domain();
+
+ e.profile = domain->profile;
+ memcpy(e.group, domain->group, sizeof(e.group));
+ }
+ e.domainname = tomoyo_get_name(domainname);
+ if (!e.domainname)
+ return NULL;
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ goto out;
+ entry = tomoyo_find_domain(domainname);
+ if (!entry) {
+ entry = tomoyo_commit_ok(&e, sizeof(e));
+ if (entry) {
+ INIT_LIST_HEAD(&entry->acl_info_list);
+ list_add_tail_rcu(&entry->list, &tomoyo_domain_list);
+ created = true;
+ }
+ }
+ mutex_unlock(&tomoyo_policy_lock);
+out:
+ tomoyo_put_name(e.domainname);
+ if (entry && transit) {
+ if (created) {
+ struct tomoyo_request_info r;
+ int i;
+
+ tomoyo_init_request_info(&r, entry,
+ TOMOYO_MAC_FILE_EXECUTE);
+ r.granted = false;
+ tomoyo_write_log(&r, "use_profile %u\n",
+ entry->profile);
+ for (i = 0; i < TOMOYO_MAX_ACL_GROUPS; i++)
+ if (test_bit(i, entry->group))
+ tomoyo_write_log(&r, "use_group %u\n",
+ i);
+ tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
+ }
+ }
+ return entry;
+}
+
+/**
+ * tomoyo_environ - Check permission for environment variable names.
+ *
+ * @ee: Pointer to "struct tomoyo_execve".
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int tomoyo_environ(struct tomoyo_execve *ee)
+{
+ struct tomoyo_request_info *r = &ee->r;
+ struct linux_binprm *bprm = ee->bprm;
+ /* env_page.data is allocated by tomoyo_dump_page(). */
+ struct tomoyo_page_dump env_page = { };
+ char *arg_ptr; /* Size is TOMOYO_EXEC_TMPSIZE bytes */
+ int arg_len = 0;
+ unsigned long pos = bprm->p;
+ int offset = pos % PAGE_SIZE;
+ int argv_count = bprm->argc;
+ int envp_count = bprm->envc;
+ int error = -ENOMEM;
+
+ ee->r.type = TOMOYO_MAC_ENVIRON;
+ ee->r.profile = r->domain->profile;
+ ee->r.mode = tomoyo_get_mode(r->domain->ns, ee->r.profile,
+ TOMOYO_MAC_ENVIRON);
+ if (!r->mode || !envp_count)
+ return 0;
+ arg_ptr = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
+ if (!arg_ptr)
+ goto out;
+ while (error == -ENOMEM) {
+ if (!tomoyo_dump_page(bprm, pos, &env_page))
+ goto out;
+ pos += PAGE_SIZE - offset;
+ /* Read. */
+ while (argv_count && offset < PAGE_SIZE) {
+ if (!env_page.data[offset++])
+ argv_count--;
+ }
+ if (argv_count) {
+ offset = 0;
+ continue;
+ }
+ while (offset < PAGE_SIZE) {
+ const unsigned char c = env_page.data[offset++];
+
+ if (c && arg_len < TOMOYO_EXEC_TMPSIZE - 10) {
+ if (c == '=') {
+ arg_ptr[arg_len++] = '\0';
+ } else if (c == '\\') {
+ arg_ptr[arg_len++] = '\\';
+ arg_ptr[arg_len++] = '\\';
+ } else if (c > ' ' && c < 127) {
+ arg_ptr[arg_len++] = c;
+ } else {
+ arg_ptr[arg_len++] = '\\';
+ arg_ptr[arg_len++] = (c >> 6) + '0';
+ arg_ptr[arg_len++]
+ = ((c >> 3) & 7) + '0';
+ arg_ptr[arg_len++] = (c & 7) + '0';
+ }
+ } else {
+ arg_ptr[arg_len] = '\0';
+ }
+ if (c)
+ continue;
+ if (tomoyo_env_perm(r, arg_ptr)) {
+ error = -EPERM;
+ break;
+ }
+ if (!--envp_count) {
+ error = 0;
+ break;
+ }
+ arg_len = 0;
+ }
+ offset = 0;
+ }
+out:
+ if (r->mode != TOMOYO_CONFIG_ENFORCING)
+ error = 0;
+ kfree(env_page.data);
+ kfree(arg_ptr);
+ return error;
+}
+
+/**
+ * tomoyo_find_next_domain - Find a domain.
+ *
+ * @bprm: Pointer to "struct linux_binprm".
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+int tomoyo_find_next_domain(struct linux_binprm *bprm)
+{
+ struct tomoyo_domain_info *old_domain = tomoyo_domain();
+ struct tomoyo_domain_info *domain = NULL;
+ const char *original_name = bprm->filename;
+ int retval = -ENOMEM;
+ bool reject_on_transition_failure = false;
+ const struct tomoyo_path_info *candidate;
+ struct tomoyo_path_info exename;
+ struct tomoyo_execve *ee = kzalloc(sizeof(*ee), GFP_NOFS);
+
+ if (!ee)
+ return -ENOMEM;
+ ee->tmp = kzalloc(TOMOYO_EXEC_TMPSIZE, GFP_NOFS);
+ if (!ee->tmp) {
+ kfree(ee);
+ return -ENOMEM;
+ }
+ /* ee->dump->data is allocated by tomoyo_dump_page(). */
+ tomoyo_init_request_info(&ee->r, NULL, TOMOYO_MAC_FILE_EXECUTE);
+ ee->r.ee = ee;
+ ee->bprm = bprm;
+ ee->r.obj = &ee->obj;
+ ee->obj.path1 = bprm->file->f_path;
+ /* Get symlink's pathname of program. */
+ retval = -ENOENT;
+ exename.name = tomoyo_realpath_nofollow(original_name);
+ if (!exename.name)
+ goto out;
+ tomoyo_fill_path_info(&exename);
+retry:
+ /* Check 'aggregator' directive. */
+ {
+ struct tomoyo_aggregator *ptr;
+ struct list_head *list =
+ &old_domain->ns->policy_list[TOMOYO_ID_AGGREGATOR];
+
+ /* Check 'aggregator' directive. */
+ candidate = &exename;
+ list_for_each_entry_rcu(ptr, list, head.list,
+ srcu_read_lock_held(&tomoyo_ss)) {
+ if (ptr->head.is_deleted ||
+ !tomoyo_path_matches_pattern(&exename,
+ ptr->original_name))
+ continue;
+ candidate = ptr->aggregated_name;
+ break;
+ }
+ }
+
+ /* Check execute permission. */
+ retval = tomoyo_execute_permission(&ee->r, candidate);
+ if (retval == TOMOYO_RETRY_REQUEST)
+ goto retry;
+ if (retval < 0)
+ goto out;
+ /*
+ * To be able to specify domainnames with wildcards, use the
+ * pathname specified in the policy (which may contain
+ * wildcard) rather than the pathname passed to execve()
+ * (which never contains wildcard).
+ */
+ if (ee->r.param.path.matched_path)
+ candidate = ee->r.param.path.matched_path;
+
+ /*
+ * Check for domain transition preference if "file execute" matched.
+ * If preference is given, make execve() fail if domain transition
+ * has failed, for domain transition preference should be used with
+ * destination domain defined.
+ */
+ if (ee->transition) {
+ const char *domainname = ee->transition->name;
+
+ reject_on_transition_failure = true;
+ if (!strcmp(domainname, "keep"))
+ goto force_keep_domain;
+ if (!strcmp(domainname, "child"))
+ goto force_child_domain;
+ if (!strcmp(domainname, "reset"))
+ goto force_reset_domain;
+ if (!strcmp(domainname, "initialize"))
+ goto force_initialize_domain;
+ if (!strcmp(domainname, "parent")) {
+ char *cp;
+
+ strncpy(ee->tmp, old_domain->domainname->name,
+ TOMOYO_EXEC_TMPSIZE - 1);
+ cp = strrchr(ee->tmp, ' ');
+ if (cp)
+ *cp = '\0';
+ } else if (*domainname == '<')
+ strncpy(ee->tmp, domainname, TOMOYO_EXEC_TMPSIZE - 1);
+ else
+ snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
+ old_domain->domainname->name, domainname);
+ goto force_jump_domain;
+ }
+ /*
+ * No domain transition preference specified.
+ * Calculate domain to transit to.
+ */
+ switch (tomoyo_transition_type(old_domain->ns, old_domain->domainname,
+ candidate)) {
+ case TOMOYO_TRANSITION_CONTROL_RESET:
+force_reset_domain:
+ /* Transit to the root of specified namespace. */
+ snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "<%s>",
+ candidate->name);
+ /*
+ * Make execve() fail if domain transition across namespaces
+ * has failed.
+ */
+ reject_on_transition_failure = true;
+ break;
+ case TOMOYO_TRANSITION_CONTROL_INITIALIZE:
+force_initialize_domain:
+ /* Transit to the child of current namespace's root. */
+ snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
+ old_domain->ns->name, candidate->name);
+ break;
+ case TOMOYO_TRANSITION_CONTROL_KEEP:
+force_keep_domain:
+ /* Keep current domain. */
+ domain = old_domain;
+ break;
+ default:
+ if (old_domain == &tomoyo_kernel_domain &&
+ !tomoyo_policy_loaded) {
+ /*
+ * Needn't to transit from kernel domain before
+ * starting /sbin/init. But transit from kernel domain
+ * if executing initializers because they might start
+ * before /sbin/init.
+ */
+ domain = old_domain;
+ break;
+ }
+force_child_domain:
+ /* Normal domain transition. */
+ snprintf(ee->tmp, TOMOYO_EXEC_TMPSIZE - 1, "%s %s",
+ old_domain->domainname->name, candidate->name);
+ break;
+ }
+force_jump_domain:
+ if (!domain)
+ domain = tomoyo_assign_domain(ee->tmp, true);
+ if (domain)
+ retval = 0;
+ else if (reject_on_transition_failure) {
+ pr_warn("ERROR: Domain '%s' not ready.\n", ee->tmp);
+ retval = -ENOMEM;
+ } else if (ee->r.mode == TOMOYO_CONFIG_ENFORCING)
+ retval = -ENOMEM;
+ else {
+ retval = 0;
+ if (!old_domain->flags[TOMOYO_DIF_TRANSITION_FAILED]) {
+ old_domain->flags[TOMOYO_DIF_TRANSITION_FAILED] = true;
+ ee->r.granted = false;
+ tomoyo_write_log(&ee->r, "%s", tomoyo_dif
+ [TOMOYO_DIF_TRANSITION_FAILED]);
+ pr_warn("ERROR: Domain '%s' not defined.\n", ee->tmp);
+ }
+ }
+ out:
+ if (!domain)
+ domain = old_domain;
+ /* Update reference count on "struct tomoyo_domain_info". */
+ {
+ struct tomoyo_task *s = tomoyo_task(current);
+
+ s->old_domain_info = s->domain_info;
+ s->domain_info = domain;
+ atomic_inc(&domain->users);
+ }
+ kfree(exename.name);
+ if (!retval) {
+ ee->r.domain = domain;
+ retval = tomoyo_environ(ee);
+ }
+ kfree(ee->tmp);
+ kfree(ee->dump.data);
+ kfree(ee);
+ return retval;
+}
+
+/**
+ * tomoyo_dump_page - Dump a page to buffer.
+ *
+ * @bprm: Pointer to "struct linux_binprm".
+ * @pos: Location to dump.
+ * @dump: Pointer to "struct tomoyo_page_dump".
+ *
+ * Returns true on success, false otherwise.
+ */
+bool tomoyo_dump_page(struct linux_binprm *bprm, unsigned long pos,
+ struct tomoyo_page_dump *dump)
+{
+ struct page *page;
+#ifdef CONFIG_MMU
+ int ret;
+#endif
+
+ /* dump->data is released by tomoyo_find_next_domain(). */
+ if (!dump->data) {
+ dump->data = kzalloc(PAGE_SIZE, GFP_NOFS);
+ if (!dump->data)
+ return false;
+ }
+ /* Same with get_arg_page(bprm, pos, 0) in fs/exec.c */
+#ifdef CONFIG_MMU
+ /*
+ * This is called at execve() time in order to dig around
+ * in the argv/environment of the new proceess
+ * (represented by bprm).
+ */
+ mmap_read_lock(bprm->mm);
+ ret = get_user_pages_remote(bprm->mm, pos, 1,
+ FOLL_FORCE, &page, NULL, NULL);
+ mmap_read_unlock(bprm->mm);
+ if (ret <= 0)
+ return false;
+#else
+ page = bprm->page[pos / PAGE_SIZE];
+#endif
+ if (page != dump->page) {
+ const unsigned int offset = pos % PAGE_SIZE;
+ /*
+ * Maybe kmap()/kunmap() should be used here.
+ * But remove_arg_zero() uses kmap_atomic()/kunmap_atomic().
+ * So do I.
+ */
+ char *kaddr = kmap_atomic(page);
+
+ dump->page = page;
+ memcpy(dump->data + offset, kaddr + offset,
+ PAGE_SIZE - offset);
+ kunmap_atomic(kaddr);
+ }
+ /* Same with put_arg_page(page) in fs/exec.c */
+#ifdef CONFIG_MMU
+ put_page(page);
+#endif
+ return true;
+}