File access control functions for TOMOYO Linux.
TOMOYO Linux checks permission in
open/creat/unlink/truncate/ftruncate/mknod/mkdir/
rmdir/symlink/link/rename/uselib/sysctl .
Each permission can be automatically accumulated into
the policy of each domain using 'learning mode'.
Signed-off-by: Kentaro Takeda <[email protected]>
Signed-off-by: Tetsuo Handa <[email protected]>
---
security/tomoyo/file.c | 1551 +++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 1551 insertions(+)
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6/security/tomoyo/file.c 2007-10-11 15:53:12.000000000 +0900
@@ -0,0 +1,1551 @@
+/*
+ * security/tomoyo/file.c
+ *
+ * File access control functions for TOMOYO Linux.
+ */
+
+#include "tomoyo.h"
+#include "realpath.h"
+#define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
+
+/************************* VARIABLES *************************/
+
+/***** The structure for globally readable files. *****/
+
+struct globally_readable_file_entry {
+ struct list_head list;
+ const struct path_info *filename;
+ u8 is_deleted;
+};
+
+/***** The structure for filename patterns. *****/
+
+struct pattern_entry {
+ struct list_head list;
+ const struct path_info *pattern;
+ u8 is_deleted;
+};
+
+/***** The structure for non-rewritable-by-default file patterns. *****/
+
+struct no_rewrite_entry {
+ struct list_head list;
+ const struct path_info *pattern;
+ u8 is_deleted;
+};
+
+/***** The structure for detailed write operations. *****/
+
+static struct {
+ const char *keyword;
+ const int paths;
+} acl_type_array[] = {
+ { "create", 1 }, /* TMY_TYPE_CREATE_ACL */
+ { "unlink", 1 }, /* TMY_TYPE_UNLINK_ACL */
+ { "mkdir", 1 }, /* TMY_TYPE_MKDIR_ACL */
+ { "rmdir", 1 }, /* TMY_TYPE_RMDIR_ACL */
+ { "mkfifo", 1 }, /* TMY_TYPE_MKFIFO_ACL */
+ { "mksock", 1 }, /* TMY_TYPE_MKSOCK_ACL */
+ { "mkblock", 1 }, /* TMY_TYPE_MKBLOCK_ACL */
+ { "mkchar", 1 }, /* TMY_TYPE_MKCHAR_ACL */
+ { "truncate", 1 }, /* TMY_TYPE_TRUNCATE_ACL */
+ { "symlink", 1 }, /* TMY_TYPE_SYMLINK_ACL */
+ { "link", 2 }, /* TMY_TYPE_LINK_ACL */
+ { "rename", 2 }, /* TMY_TYPE_RENAME_ACL */
+ { "rewrite", 1 }, /* TMY_TYPE_REWRITE_ACL */
+ { NULL, 0 }
+};
+
+/************************* UTILITY FUNCTIONS *************************/
+
+/**
+ * tmy_acltype2keyword - get keyword from access control index.
+ * @acl_type: index number.
+ *
+ * Returns keyword that corresponds with @acl_type .
+ */
+const char *tmy_acltype2keyword(const unsigned int acl_type)
+{
+ return (acl_type < ARRAY_SIZE(acl_type_array))
+ ? acl_type_array[acl_type].keyword : NULL;
+}
+
+/**
+ * tmy_acltype2paths - get number of arguments from access control index.
+ * @acl_type: index number.
+ *
+ * Returns number of arguments that corresponds with @acl_type .
+ */
+int tmy_acltype2paths(const unsigned int acl_type)
+{
+ return (acl_type < ARRAY_SIZE(acl_type_array))
+ ? acl_type_array[acl_type].paths : 0;
+}
+
+static int tmy_strendswith(const char *name, const char *tail)
+{
+ int len;
+
+ if (!name || !tail)
+ return 0;
+
+ len = strlen(name) - strlen(tail);
+ return len >= 0 && strcmp(name + len, tail) == 0;
+}
+
+static struct path_info *tmy_get_path(struct dentry *dentry,
+ struct vfsmount *mnt)
+{
+ /* sizeof(struct path_info_with_data) <= PAGE_SIZE */
+ struct path_info_with_data {
+ /* Keep this first, this pointer is passed to tmy_free(). */
+ struct path_info head;
+ char bariier1[16];
+ char body[TMY_MAX_PATHNAME_LEN];
+ char barrier2[16];
+ } *buf = tmy_alloc(sizeof(*buf));
+
+ if (buf) {
+ int error = tmy_realpath_dentry2(dentry,
+ mnt,
+ buf->body,
+ sizeof(buf->body) - 1);
+
+ if (error == 0) {
+ buf->head.name = buf->body;
+ tmy_fill_path_info(&buf->head);
+ return &buf->head;
+ }
+
+ tmy_free(buf);
+ buf = NULL;
+ printk(KERN_INFO "tmy_realpath_dentry = %d\n", error);
+ }
+
+ return NULL;
+}
+
+/************************* PROTOTYPES *************************/
+
+static int tmy_add_double_write_acl(const u8 type,
+ const char *filename1,
+ const char *filename2,
+ struct domain_info * const domain,
+ const struct condition_list *cond,
+ const u8 is_delete);
+static int tmy_add_single_write_acl(const u8 type,
+ const char *filename,
+ struct domain_info * const domain,
+ const struct condition_list *cond,
+ const u8 is_delete);
+
+/************************* AUDIT FUNCTIONS *************************/
+
+static int tmy_audit_file_log(const struct path_info *filename,
+ const u8 perm,
+ const u8 is_granted,
+ const u8 is_enforce)
+{
+ char *buf;
+ int len;
+
+ if (is_granted) {
+ if (!tmy_audit_grant())
+ return 0;
+ } else {
+ if (!tmy_audit_reject())
+ return 0;
+ }
+
+ len = filename->total_len + 8;
+ buf = tmy_init_audit_log(&len);
+
+ if (!buf)
+ return -ENOMEM;
+
+ snprintf(buf + strlen(buf),
+ len - strlen(buf) - 1,
+ "%d %s",
+ perm,
+ filename->name);
+
+ return tmy_write_audit_log(buf, is_granted, is_enforce);
+}
+
+static int tmy_audit_write_log(const char *operation,
+ const struct path_info *filename1,
+ const struct path_info *filename2,
+ const u8 is_granted,
+ const u8 is_enforce)
+{
+ char *buf;
+ int len;
+
+ if (is_granted) {
+ if (!tmy_audit_grant())
+ return 0;
+ } else {
+ if (!tmy_audit_reject())
+ return 0;
+ }
+
+ len = strlen(operation) +
+ filename1->total_len +
+ (filename2 ? filename2->total_len : 0)
+ + 16;
+
+ buf = tmy_init_audit_log(&len);
+ if (!buf)
+ return -ENOMEM;
+
+ snprintf(buf + strlen(buf), len - strlen(buf) - 1,
+ "allow_%s %s %s",
+ operation, filename1->name, filename2 ? filename2->name : "");
+
+ return tmy_write_audit_log(buf, is_granted, is_enforce);
+}
+
+/********************** GLOBALLY READABLE FILE HANDLER **********************/
+
+static LIST_HEAD(globally_readable_file_entry_list);
+
+static int tmy_add_globally_readable_entry(const char *filename,
+ const u8 is_delete)
+{
+ struct globally_readable_file_entry *new_entry;
+ struct globally_readable_file_entry *ptr;
+ static DEFINE_MUTEX(mutex);
+ const struct path_info *saved;
+ int error = -ENOMEM;
+
+ if (!tmy_correct_path(filename, 1, -1, -1, __FUNCTION__))
+ return -EINVAL; /* No patterns allowed. */
+ saved = tmy_save_name(filename);
+ if (!saved)
+ return -ENOMEM;
+
+ mutex_lock(&mutex);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &globally_readable_file_entry_list, list) {
+ if (ptr->filename != saved)
+ continue;
+ ptr->is_deleted = is_delete;
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+ if (!error)
+ goto out;
+ if (is_delete) {
+ error = -ENOENT;
+ goto out;
+ }
+
+ new_entry = tmy_alloc_element(sizeof(*new_entry));
+ if (!new_entry)
+ goto out;
+
+ new_entry->filename = saved;
+ mb(); /* Avoid out-of-order execution. */
+ /* RCU: Protected by mutex. */
+ list_add_tail_rcu(&new_entry->list, &globally_readable_file_entry_list);
+ error = 0;
+out: ;
+ mutex_unlock(&mutex);
+ return error;
+}
+
+static int tmy_globally_readable(const struct path_info *filename)
+{
+ struct globally_readable_file_entry *ptr;
+ u8 found = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &globally_readable_file_entry_list, list) {
+ if (ptr->is_deleted || tmy_pathcmp(filename, ptr->filename))
+ continue;
+ found = 1;
+ break;
+ }
+ rcu_read_unlock();
+ return found;
+}
+
+/**
+ * tmy_add_globally_readable_policy - add or delete globally readable policy.
+ * @filename: pointer to filename to add ore remove.
+ * @is_delete: is this delete request?
+ *
+ * Returns zero on success.
+ * Returns nonzero on failure.
+ */
+int tmy_add_globally_readable_policy(char *filename, const u8 is_delete)
+{
+ return tmy_add_globally_readable_entry(filename, is_delete);
+}
+
+/**
+ * tmy_read_globally_readable_policy - read globally readable policy.
+ * @head: pointer to "struct io_buffer".
+ *
+ * Returns nonzero if reading incomplete.
+ * Returns zero otherwise.
+ */
+int tmy_read_globally_readable_policy(struct io_buffer *head)
+{
+ struct list_head *pos;
+ int error = -ENOMEM;
+
+ rcu_read_lock();
+ pos = head->read_var2;
+ if (!pos)
+ pos = &globally_readable_file_entry_list;
+ list_for_each_continue_rcu(pos, &globally_readable_file_entry_list) {
+ struct globally_readable_file_entry *ptr;
+ ptr = list_entry(pos, struct globally_readable_file_entry,
+ list);
+ head->read_var2 = pos->prev;
+ if (ptr->is_deleted)
+ continue;
+ if (tmy_io_printf(head, TMY_ALLOW_READ "%s\n",
+ ptr->filename->name))
+ goto out;
+ }
+ error = 0;
+out: ;
+ rcu_read_unlock();
+ return error;
+}
+
+/************************* FILE GROUP HANDLER *************************/
+
+static LIST_HEAD(path_group_entry_list);
+
+static int tmy_add_group_entry(const char *group_name,
+ const char *member_name,
+ const u8 is_delete)
+{
+ static DEFINE_MUTEX(mutex);
+ struct path_group_entry *new_group;
+ struct path_group_entry *group;
+ struct path_group_member *new_member;
+ struct path_group_member *member;
+ const struct path_info *saved_group;
+ const struct path_info *saved_member;
+ int error = -ENOMEM;
+ u8 group_found = 0;
+
+ if (!tmy_correct_path(group_name, 0, 0, 0, __FUNCTION__) ||
+ !group_name[0] ||
+ !tmy_correct_path(member_name, 0, 0, 0, __FUNCTION__) ||
+ !member_name[0])
+ return -EINVAL;
+
+ saved_group = tmy_save_name(group_name);
+ saved_member = tmy_save_name(member_name);
+
+ if (!saved_group || !saved_member)
+ return -ENOMEM;
+
+ mutex_lock(&mutex);
+ rcu_read_lock();
+ list_for_each_entry_rcu(group, &path_group_entry_list, list) {
+ if (saved_group != group->group_name)
+ continue;
+ group_found = 1;
+ list_for_each_entry_rcu(member, &group->path_group_member_list,
+ list) {
+ if (member->member_name == saved_member) {
+ member->is_deleted = is_delete;
+ error = 0;
+ break;
+ }
+ }
+ break;
+ }
+ rcu_read_unlock();
+ if (!error)
+ goto out;
+
+ if (is_delete) {
+ error = -ENOENT;
+ goto out;
+ }
+
+ if (!group_found) {
+ new_group = tmy_alloc_element(sizeof(*new_group));
+ if (!new_group)
+ goto out;
+ INIT_LIST_HEAD(&new_group->path_group_member_list);
+ new_group->group_name = saved_group;
+ mb(); /* Avoid out-of-order execution. */
+ /* RCU: Protected by mutex. */
+ list_add_tail_rcu(&new_group->list, &path_group_entry_list);
+ group = new_group;
+ }
+
+ new_member = tmy_alloc_element(sizeof(*new_member));
+ if (!new_member)
+ goto out;
+
+ INIT_LIST_HEAD(&new_member->list);
+ new_member->member_name = saved_member;
+ mb(); /* Avoid out-of-order execution. */
+ /* RCU: Protected by mutex. */
+ list_add_tail_rcu(&new_member->list, &group->path_group_member_list);
+ error = 0;
+out: ;
+ mutex_unlock(&mutex);
+
+ return error;
+}
+
+/**
+ * tmy_add_group_policy - add or delete path group policy.
+ * @data: a line to parse.
+ * @is_delete: is this delete request?
+ *
+ * Returns zero on success.
+ * Returns nonzero on failure.
+ */
+int tmy_add_group_policy(char *data, const u8 is_delete)
+{
+ char *cp = strchr(data, ' ');
+
+ if (!cp)
+ return -EINVAL;
+ *cp++ = '\0';
+ return tmy_add_group_entry(data, cp, is_delete);
+}
+
+static struct path_group_entry *tmy_new_path_group(const char *group_name)
+{
+ int i;
+ struct path_group_entry *group;
+ u8 found = 0;
+
+ for (i = 0; i <= 1; i++) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(group, &path_group_entry_list, list) {
+ if (strcmp(group_name, group->group_name->name) == 0) {
+ found = 1;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ if (found)
+ return group;
+ if (i == 0) {
+ /*
+ * Add a dummy entry to create new path group
+ * and delete that entry.
+ */
+ tmy_add_group_entry(group_name, "/", 0);
+ tmy_add_group_entry(group_name, "/", 1);
+ }
+ }
+ return NULL;
+}
+
+static int tmy_path_match_group(const struct path_info *pathname,
+ const struct path_group_entry *group,
+ const int may_use_pattern)
+{
+ struct path_group_member *member;
+ u8 found = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(member, &group->path_group_member_list, list) {
+ if (member->is_deleted)
+ continue;
+ if (!member->member_name->is_patterned) {
+ if (!tmy_pathcmp(pathname, member->member_name)) {
+ found = 1;
+ break;
+ }
+ } else if (may_use_pattern) {
+ if (tmy_path_match(pathname, member->member_name)) {
+ found = 1;
+ break;
+ }
+ }
+ }
+ rcu_read_unlock();
+ return found;
+}
+
+/**
+ * tmy_read_path_group_policy - read path group policy.
+ * @head: pointer to "struct io_buffer".
+ *
+ * Returns nonzero if reading incomplete.
+ * Returns zero otherwise.
+ */
+int tmy_read_path_group_policy(struct io_buffer *head)
+{
+ struct list_head *gpos;
+ struct list_head *mpos;
+ int error = -ENOMEM;
+
+ rcu_read_lock();
+ gpos = head->read_var1;
+ if (!gpos)
+ gpos = &path_group_entry_list;
+ list_for_each_continue_rcu(gpos, &path_group_entry_list) {
+ struct path_group_entry *group;
+ group = list_entry(gpos, struct path_group_entry, list);
+ head->read_var1 = gpos->prev;
+ mpos = head->read_var2;
+ if (!mpos)
+ mpos = &group->path_group_member_list;
+ list_for_each_continue_rcu(mpos,
+ &group->path_group_member_list) {
+ struct path_group_member *member;
+ member = list_entry(mpos, struct path_group_member,
+ list);
+ head->read_var2 = mpos->prev;
+ if (member->is_deleted)
+ continue;
+ if (tmy_io_printf(head,
+ TMY_PATH_GROUP "%s %s\n",
+ group->group_name->name,
+ member->member_name->name))
+ goto out;
+ }
+ head->read_var2 = NULL;
+ }
+ error = 0;
+out: ;
+ rcu_read_unlock();
+ return error;
+}
+
+/************************* FILE PATTERN HANDLER *************************/
+
+static LIST_HEAD(pattern_entry_list);
+
+static int tmy_add_pattern_entry(const char *pattern, const u8 is_delete)
+{
+ struct pattern_entry *new_entry;
+ struct pattern_entry *ptr;
+ static DEFINE_MUTEX(mutex);
+ const struct path_info *saved;
+ int error = -ENOMEM;
+
+ if (!tmy_correct_path(pattern, 0, 1, 0, __FUNCTION__))
+ return -EINVAL;
+
+ saved = tmy_save_name(pattern);
+ if (!saved)
+ return -ENOMEM;
+
+ mutex_lock(&mutex);
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &pattern_entry_list, list) {
+ if (saved != ptr->pattern)
+ continue;
+ ptr->is_deleted = is_delete;
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+ if (!error)
+ goto out;
+
+ if (is_delete) {
+ error = -ENOENT;
+ goto out;
+ }
+
+ new_entry = tmy_alloc_element(sizeof(*new_entry));
+ if (!new_entry)
+ goto out;
+ new_entry->pattern = saved;
+ mb(); /* Avoid out-of-order execution. */
+ /* RCU: Protected by mutex. */
+ list_add_tail_rcu(&new_entry->list, &pattern_entry_list);
+ error = 0;
+out: ;
+ mutex_unlock(&mutex);
+ return error;
+}
+
+static const struct path_info *tmy_get_pattern(const struct path_info *filename)
+{
+ struct pattern_entry *ptr;
+ const struct path_info *pattern = NULL;
+ u8 found = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &pattern_entry_list, list) {
+ if (ptr->is_deleted)
+ continue;
+ if (!tmy_path_match(filename, ptr->pattern))
+ continue;
+ pattern = ptr->pattern;
+ if (!tmy_strendswith(pattern->name, "/\\*")) {
+ found = 1;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ if (found)
+ filename = pattern;
+ return filename;
+}
+
+/**
+ * tmy_add_pattern_policy - add or delete file pattern policy.
+ * @pattern: pointer to file pattern entry.
+ * @is_delete: is this delete request?
+ *
+ * Returns zero on success.
+ * Returns nonzero on failure.
+ */
+int tmy_add_pattern_policy(char *pattern, const u8 is_delete)
+{
+ return tmy_add_pattern_entry(pattern, is_delete);
+}
+
+/**
+ * tmy_read_pattern_policy - read file pattern policy.
+ * @head: pointer to "struct io_buffer".
+ *
+ * Returns nonzero if reading incomplete.
+ * Returns zero otherwise.
+ */
+int tmy_read_pattern_policy(struct io_buffer *head)
+{
+ struct list_head *pos;
+ int error = -ENOMEM;
+
+ rcu_read_lock();
+ pos = head->read_var2;
+ if (!pos)
+ pos = &pattern_entry_list;
+ list_for_each_continue_rcu(pos, &pattern_entry_list) {
+ struct pattern_entry *ptr;
+ ptr = list_entry(pos, struct pattern_entry, list);
+ head->read_var2 = pos->prev;
+ if (ptr->is_deleted)
+ continue;
+ if (tmy_io_printf(head, TMY_FILE_PATTERN "%s\n",
+ ptr->pattern->name))
+ goto out;
+ }
+ error = 0;
+out: ;
+ rcu_read_unlock();
+ return error;
+}
+
+/*********************** NON REWRITABLE FILE HANDLER ***********************/
+
+static LIST_HEAD(no_rewrite_entry_list);
+
+static int tmy_add_no_rewrite_entry(const char *pattern, const u8 is_delete)
+{
+ struct no_rewrite_entry *new_entry;
+ struct no_rewrite_entry *ptr;
+ static DEFINE_MUTEX(mutex);
+ const struct path_info *saved;
+ int error = -ENOMEM;
+
+ if (!tmy_correct_path(pattern, 0, 0, 0, __FUNCTION__))
+ return -EINVAL;
+ saved = tmy_save_name(pattern);
+ if (!saved)
+ return -ENOMEM;
+
+ mutex_lock(&mutex);
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &no_rewrite_entry_list, list) {
+ if (ptr->pattern != saved)
+ continue;
+ ptr->is_deleted = is_delete;
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+ if (!error)
+ goto out;
+
+ if (is_delete) {
+ error = -ENOENT;
+ goto out;
+ }
+
+ new_entry = tmy_alloc_element(sizeof(*new_entry));
+ if (!new_entry)
+ goto out;
+ new_entry->pattern = saved;
+ mb(); /* Avoid out-of-order execution. */
+ /* RCU: Protected by mutex. */
+ list_add_tail_rcu(&new_entry->list, &no_rewrite_entry_list);
+ error = 0;
+out: ;
+ mutex_unlock(&mutex);
+ return error;
+}
+
+static int tmy_is_no_rewrite_file(const struct path_info *filename)
+{
+ struct no_rewrite_entry *ptr;
+ u8 found = 0;
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &no_rewrite_entry_list, list) {
+ if (ptr->is_deleted)
+ continue;
+ if (!tmy_path_match(filename, ptr->pattern))
+ continue;
+ found = 1;
+ break;
+ }
+ rcu_read_unlock();
+ return found;
+}
+
+/**
+ * tmy_add_no_rewrite_policy - add or delete no-rewrite policy.
+ * @pattern: pointer to no-rewrite entry.
+ * @is_delete: is this delete request?
+ *
+ * Returns zero on success.
+ * Returns nonzero on failure.
+ */
+int tmy_add_no_rewrite_policy(char *pattern, const u8 is_delete)
+{
+ return tmy_add_no_rewrite_entry(pattern, is_delete);
+}
+
+/**
+ * tmy_read_no_rewrite_policy - read no-rewrite policy.
+ * @head: pointer to "struct io_buffer".
+ *
+ * Returns nonzero if reading incomplete.
+ * Returns zero otherwise.
+ */
+int tmy_read_no_rewrite_policy(struct io_buffer *head)
+{
+ struct list_head *pos;
+ int error = -ENOMEM;
+
+ rcu_read_lock();
+ pos = head->read_var2;
+ if (!pos)
+ pos = &no_rewrite_entry_list;
+ list_for_each_continue_rcu(pos, &no_rewrite_entry_list) {
+ struct no_rewrite_entry *ptr;
+ ptr = list_entry(pos, struct no_rewrite_entry, list);
+ head->read_var2 = pos->prev;
+ if (ptr->is_deleted)
+ continue;
+ if (tmy_io_printf(head, TMY_DENY_REWRITE "%s\n",
+ ptr->pattern->name))
+ goto out;
+ }
+ error = 0;
+out: ;
+ rcu_read_unlock();
+ return error;
+}
+
+/************************* FILE ACL HANDLER *************************/
+
+static int tmy_add_file_acl(const char *filename,
+ u8 perm,
+ struct domain_info * const domain,
+ const struct condition_list *cond,
+ const u8 is_delete)
+{
+ const struct path_info *saved;
+ struct acl_info *ptr;
+ struct file_acl *acl;
+ int error = -ENOMEM;
+ u8 is_group = 0;
+
+ if (!domain)
+ return -EINVAL;
+ if (perm > 7 || !perm) {
+ printk(KERN_DEBUG "%s: Invalid permission '%d %s'\n",
+ __FUNCTION__, perm, filename);
+ return -EINVAL;
+ }
+ if (!tmy_correct_path(filename, 0, 0, 0, __FUNCTION__))
+ return -EINVAL;
+
+ if (filename[0] == '@') {
+ /* This cast is OK because I don't dereference. */
+ saved = (struct path_info *) tmy_new_path_group(filename + 1);
+ if (!saved)
+ return -ENOMEM;
+ is_group = 1;
+ } else {
+
+ if (tmy_strendswith(filename, "/"))
+ /*
+ * Valid permissions for directory are
+ * only 'allow_mkdir' and 'allow_rmdir'.
+ */
+ return 0;
+
+ saved = tmy_save_name(filename);
+ if (!saved)
+ return -ENOMEM;
+
+ if (!is_delete && perm == 4 &&
+ tmy_globally_readable(saved))
+ return 0;
+
+ }
+
+ mutex_lock(&domain_acl_lock);
+
+ if (is_delete)
+ goto remove;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ acl = container_of(ptr, struct file_acl, head);
+ if (ptr->type != TMY_TYPE_FILE_ACL ||
+ ptr->cond != cond ||
+ acl->u.filename != saved)
+ continue;
+ if (ptr->is_deleted) {
+ acl->perm = 0;
+ mb(); /* Avoid out-of-order execution. */
+ ptr->is_deleted = 0;
+ }
+ acl->perm |= perm;
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+
+ if (!error) {
+ tmy_update_counter(TMY_UPDATE_DOMAINPOLICY);
+ goto ok;
+ }
+
+ /* Not found. Append it to the tail. */
+ acl = tmy_alloc_element(sizeof(*acl));
+ if (!acl)
+ goto ok;
+ acl->head.type = TMY_TYPE_FILE_ACL;
+ acl->head.cond = cond;
+ acl->perm = perm;
+ acl->u_is_group = is_group;
+ acl->u.filename = saved;
+ error = tmy_add_acl(domain, &acl->head);
+ goto ok;
+remove: ;
+ error = -ENOENT;
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ acl = container_of(ptr, struct file_acl, head);
+ if (ptr->type != TMY_TYPE_FILE_ACL ||
+ ptr->cond != cond ||
+ ptr->is_deleted ||
+ acl->perm != perm ||
+ acl->u.filename != saved)
+ continue;
+ error = tmy_del_acl(ptr);
+ break;
+ }
+ rcu_read_unlock();
+ok: ;
+ mutex_unlock(&domain_acl_lock);
+ return error;
+}
+
+static int tmy_file_acl(const struct path_info *filename, const u8 perm,
+ struct obj_info *obj)
+{
+ const struct domain_info *domain = TMY_SECURITY->domain;
+ struct acl_info *ptr;
+ const int may_use_pat = ((perm & 1) == 0);
+ int error = -EPERM;
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+ if (!filename->is_dir) {
+ if (perm == 4 && tmy_globally_readable(filename))
+ return 0;
+ }
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ struct file_acl *acl;
+ acl = container_of(ptr, struct file_acl, head);
+ if (ptr->type != TMY_TYPE_FILE_ACL ||
+ ptr->is_deleted ||
+ (acl->perm & perm) != perm ||
+ tmy_check_condition(ptr->cond, obj))
+ continue;
+ if (acl->u_is_group) {
+ if (tmy_path_match_group(filename,
+ acl->u.group,
+ may_use_pat)) {
+ error = 0;
+ break;
+ }
+ } else {
+ if ((may_use_pat || !acl->u.filename->is_patterned) &&
+ tmy_path_match(filename, acl->u.filename)) {
+ error = 0;
+ break;
+ }
+ }
+ }
+ rcu_read_unlock();
+ return error;
+}
+
+static int tmy_file_perm2(const struct path_info *filename,
+ const u8 perm,
+ struct obj_info *obj,
+ const char *operation)
+{
+ int error = 0;
+ struct domain_info * const domain = TMY_SECURITY->domain;
+ const u8 is_enforce = tmy_enforce(TMY_MAC_FOR_FILE);
+
+ if (!filename)
+ return 0;
+
+ error = tmy_file_acl(filename, perm, obj);
+
+ tmy_audit_file_log(filename, perm, !error, is_enforce);
+
+ if (!error)
+ return error;
+
+ if (is_enforce)
+ error = tmy_supervisor("%s\n%d %s\n",
+ domain->domainname->name,
+ perm, filename->name);
+
+ else if (tmy_accept(TMY_MAC_FOR_FILE, domain)) {
+ /* Don't use patterns if execution bit is on. */
+ const struct path_info *patterned =
+ ((perm & 1) == 0) ?
+ tmy_get_pattern(filename) : filename;
+ tmy_add_file_acl(patterned->name, perm, domain, NULL, 0);
+ }
+
+ if (!is_enforce)
+ error = 0;
+
+ return error;
+}
+
+/**
+ * tmy_file_perm - check permission for sysctl(2) operation.
+ * @filename0: pointer to filename returned by sysctlpath_from_table().
+ * @perm: mode (read = 4, write = 2, read-write = 6).
+ * @operation: pointer to error message.
+ *
+ * Returns zero if permission granted.
+ * Returns nonzero if permission denied.
+ */
+int tmy_file_perm(const char *filename0, const u8 perm, const char *operation)
+{
+ struct path_info filename;
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+
+ filename.name = filename0;
+ tmy_fill_path_info(&filename);
+
+ return tmy_file_perm2(&filename, perm, NULL, operation);
+}
+
+/**
+ * tmy_add_file_policy - add or delete file policy.
+ * @data: a line to parse.
+ * @domain: pointer to "struct domain_info".
+ * @cond: pointer to "struct condition_list". May be NULL.
+ * @is_delete: is this delete request?
+ *
+ * Returns zero on success.
+ * Returns nonzero on failure.
+ */
+int tmy_add_file_policy(char *data,
+ struct domain_info *domain,
+ const struct condition_list *cond,
+ const u8 is_delete)
+{
+ char *filename = strchr(data, ' ');
+ unsigned int perm;
+ u8 type;
+
+ if (!filename)
+ return -EINVAL;
+ *filename++ = '\0';
+
+ if (sscanf(data, "%u", &perm) == 1)
+ return tmy_add_file_acl(filename, (u8) perm, domain, cond,
+ is_delete);
+
+ if (strncmp(data, "allow_", 6))
+ goto out;
+
+ data += 6;
+
+ for (type = 0; acl_type_array[type].keyword; type++) {
+ if (strcmp(data, acl_type_array[type].keyword))
+ continue;
+
+ if (acl_type_array[type].paths == 2) {
+ char *filename2 = strchr(filename, ' ');
+
+ if (!filename2)
+ break;
+ *filename2++ = '\0';
+ return tmy_add_double_write_acl(type, filename,
+ filename2,
+ domain, cond,
+ is_delete);
+ } else
+ return tmy_add_single_write_acl(type, filename,
+ domain, cond,
+ is_delete);
+
+ break;
+ }
+out: ;
+ return -EINVAL;
+}
+
+static int tmy_add_single_write_acl(const u8 type,
+ const char *filename,
+ struct domain_info * const domain,
+ const struct condition_list *cond,
+ const u8 is_delete)
+{
+ const struct path_info *saved;
+ struct acl_info *ptr;
+ struct single_acl *acl;
+ int error = -ENOMEM;
+ u8 is_group = 0;
+
+ if (!domain)
+ return -EINVAL;
+ if (!tmy_correct_path(filename, 0, 0, 0, __FUNCTION__))
+ return -EINVAL;
+
+ if (filename[0] == '@') {
+ /* This cast is OK because I don't dereference. */
+ saved = (struct path_info *) tmy_new_path_group(filename + 1);
+ if (!saved)
+ return -ENOMEM;
+ is_group = 1;
+ } else {
+ saved = tmy_save_name(filename);
+ if (!saved)
+ return -ENOMEM;
+ }
+
+ mutex_lock(&domain_acl_lock);
+ if (is_delete)
+ goto remove;
+
+ /* Scan the list for the same entry. */
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ acl = container_of(ptr, struct single_acl, head);
+ if (ptr->type != type ||
+ ptr->cond != cond ||
+ acl->u.filename != saved)
+ continue;
+ ptr->is_deleted = 0;
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+
+ if (!error)
+ goto ok;
+
+ /* Not found. Append it to the tail. */
+ acl = tmy_alloc_element(sizeof(*acl));
+ if (!acl)
+ goto ok;
+ acl->head.type = type;
+ acl->head.cond = cond;
+ acl->u_is_group = is_group;
+ acl->u.filename = saved;
+ error = tmy_add_acl(domain, &acl->head);
+ goto ok;
+remove: ;
+ error = -ENOENT;
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ acl = container_of(ptr, struct single_acl, head);
+ if (ptr->type != type || ptr->is_deleted ||
+ ptr->cond != cond || acl->u.filename != saved)
+ continue;
+ error = tmy_del_acl(ptr);
+ break;
+ }
+ rcu_read_unlock();
+ok: ;
+ mutex_unlock(&domain_acl_lock);
+
+ return error;
+}
+
+static int tmy_add_double_write_acl(const u8 type,
+ const char *filename1,
+ const char *filename2,
+ struct domain_info * const domain,
+ const struct condition_list *cond,
+ const u8 is_delete)
+{
+ const struct path_info *saved1;
+ const struct path_info *saved2;
+ struct acl_info *ptr;
+ struct double_acl *acl;
+ int error = -ENOMEM;
+ u8 is_group1 = 0;
+ u8 is_group2 = 0;
+
+ if (!domain)
+ return -EINVAL;
+ if (!tmy_correct_path(filename1, 0, 0, 0, __FUNCTION__) ||
+ !tmy_correct_path(filename2, 0, 0, 0, __FUNCTION__))
+ return -EINVAL;
+
+ if (filename1[0] == '@') {
+ /* This cast is OK because I don't dereference. */
+ saved1 = (struct path_info *) tmy_new_path_group(filename1 + 1);
+ if (!saved1)
+ return -ENOMEM;
+ is_group1 = 1;
+ } else {
+ saved1 = tmy_save_name(filename1);
+ if (!saved1)
+ return -ENOMEM;
+ }
+
+ if (filename2[0] == '@') {
+ /* This cast is OK because I don't dereference. */
+ saved2 = (struct path_info *) tmy_new_path_group(filename2 + 1);
+ if (!saved2)
+ return -ENOMEM;
+ is_group2 = 1;
+ } else {
+ saved2 = tmy_save_name(filename2);
+ if (!saved2)
+ return -ENOMEM;
+ }
+
+ mutex_lock(&domain_acl_lock);
+
+ if (is_delete)
+ goto remove;
+
+ /* Scan the list for the same entry. */
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ acl = container_of(ptr, struct double_acl, head);
+ if (ptr->type != type || ptr->cond != cond ||
+ acl->u1.filename1 != saved1 ||
+ acl->u2.filename2 != saved2)
+ continue;
+ ptr->is_deleted = 0;
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+
+ if (!error)
+ goto ok;
+
+ /* Not found. Append it to the tail. */
+ acl = tmy_alloc_element(sizeof(*acl));
+ if (!acl)
+ goto ok;
+ acl->head.type = type;
+ acl->head.cond = cond;
+ acl->u1_is_group = is_group1;
+ acl->u2_is_group = is_group2;
+ acl->u1.filename1 = saved1;
+ acl->u2.filename2 = saved2;
+ error = tmy_add_acl(domain, &acl->head);
+ goto ok;
+remove: ;
+ error = -ENOENT;
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ acl = container_of(ptr, struct double_acl, head);
+ if (ptr->type != type || ptr->is_deleted ||
+ ptr->cond != cond ||
+ acl->u1.filename1 != saved1 ||
+ acl->u2.filename2 != saved2)
+ continue;
+ error = tmy_del_acl(ptr);
+ break;
+ }
+ rcu_read_unlock();
+ok: ;
+ mutex_unlock(&domain_acl_lock);
+ return error;
+}
+
+static int tmy_single_write_acl(const u8 type,
+ const struct path_info *filename,
+ struct obj_info *obj)
+{
+ const struct domain_info *domain = TMY_SECURITY->domain;
+ struct acl_info *ptr;
+ int error = -EPERM;
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ struct single_acl *acl;
+ acl = container_of(ptr, struct single_acl, head);
+ if (ptr->type != type || ptr->is_deleted ||
+ tmy_check_condition(ptr->cond, obj))
+ continue;
+ if (acl->u_is_group) {
+ if (tmy_path_match_group(filename, acl->u.group, 1)) {
+ error = 0;
+ break;
+ }
+ } else {
+ if (tmy_path_match(filename, acl->u.filename)) {
+ error = 0;
+ break;
+ }
+ }
+ }
+ rcu_read_unlock();
+ return error;
+}
+
+static int tmy_double_write_acl(const u8 type,
+ const struct path_info *filename1,
+ const struct path_info *filename2,
+ struct obj_info *obj)
+{
+ const struct domain_info *domain = TMY_SECURITY->domain;
+ struct acl_info *ptr;
+ int error = -EPERM;
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
+ struct double_acl *acl;
+ acl = container_of(ptr, struct double_acl, head);
+ if (ptr->type != type || ptr->is_deleted ||
+ tmy_check_condition(ptr->cond, obj))
+ continue;
+ if (acl->u1_is_group) {
+ if (!tmy_path_match_group(filename1,
+ acl->u1.group1, 1))
+ continue;
+ } else {
+ if (!tmy_path_match(filename1, acl->u1.filename1))
+ continue;
+ }
+ if (acl->u2_is_group) {
+ if (!tmy_path_match_group(filename2,
+ acl->u2.group2, 1))
+ continue;
+ } else {
+ if (!tmy_path_match(filename2, acl->u2.filename2))
+ continue;
+ }
+ error = 0;
+ break;
+ }
+ rcu_read_unlock();
+ return error;
+}
+
+static int tmy_single_write_perm2(const unsigned int operation,
+ const struct path_info *filename,
+ struct obj_info *obj)
+{
+ int error;
+ struct domain_info * const domain = TMY_SECURITY->domain;
+ const u8 is_enforce = tmy_enforce(TMY_MAC_FOR_FILE);
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+
+ error = tmy_single_write_acl(operation, filename, obj);
+
+ tmy_audit_write_log(tmy_acltype2keyword(operation),
+ filename, NULL, !error, is_enforce);
+
+ if (!error)
+ goto ok;
+
+ if (is_enforce)
+ error = tmy_supervisor("%s\nallow_%s %s\n",
+ domain->domainname->name,
+ tmy_acltype2keyword(operation),
+ filename->name);
+
+ else if (tmy_accept(TMY_MAC_FOR_FILE, domain))
+ tmy_add_single_write_acl(operation,
+ tmy_get_pattern(filename)->name,
+ domain, NULL, 0);
+
+ if (!is_enforce)
+ error = 0;
+
+ok: ;
+ if (!error && operation == TMY_TYPE_TRUNCATE_ACL &&
+ tmy_is_no_rewrite_file(filename))
+ error = tmy_single_write_perm2(TMY_TYPE_REWRITE_ACL,
+ filename, obj);
+
+ return error;
+}
+
+/**
+ * tmy_exec_perm - check permission for execve(2) operation.
+ * @filename: pointer to filename to execute.
+ * @filp: pointer to "struct file".
+ *
+ * Returns zero if permission granted.
+ * Returns nonzero if permission denied.
+ */
+int tmy_exec_perm(const struct path_info *filename, struct file *filp)
+{
+ struct obj_info obj;
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+ memset(&obj, 0, sizeof(obj));
+ obj.path1_dentry = filp->f_dentry;
+ obj.path1_vfsmnt = filp->f_vfsmnt;
+ return tmy_file_perm2(filename, 1, &obj, "do_execve");
+}
+
+/**
+ * tmy_open_perm - check permission for open(2) operation.
+ * @dentry: pointer to "struct dentry".
+ * @mnt: pointer to "struct vfsmount".
+ * @flag: open flags.
+ *
+ * Returns zero if permission granted.
+ * Returns nonzero if permission denied.
+ */
+int tmy_open_perm(struct dentry *dentry,
+ struct vfsmount *mnt,
+ const int flag)
+{
+ struct obj_info obj;
+ const int acc_mode = ACC_MODE(flag);
+ int error = -ENOMEM;
+ struct path_info *buf;
+ const u8 is_enforce = tmy_enforce(TMY_MAC_FOR_FILE);
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+ if (acc_mode == 0)
+ return 0;
+ if (dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode))
+ /* I don't check directories here */
+ /* because mkdir() and rmdir() don't call me. */
+ return 0;
+
+ buf = tmy_get_path(dentry, mnt);
+
+ if (!buf)
+ goto out;
+
+ memset(&obj, 0, sizeof(obj));
+ obj.path1_dentry = dentry;
+ obj.path1_vfsmnt = mnt;
+
+ error = 0;
+ if ((acc_mode & MAY_WRITE) &&
+ ((flag & O_TRUNC) || !(flag & O_APPEND)) &&
+ tmy_is_no_rewrite_file(buf))
+ error = tmy_single_write_perm2(TMY_TYPE_REWRITE_ACL,
+ buf, &obj);
+
+ if (error == 0)
+ error = tmy_file_perm2(buf, acc_mode, &obj, "open");
+
+ if (error == 0 && (flag & O_TRUNC))
+ error = tmy_single_write_perm2(TMY_TYPE_TRUNCATE_ACL,
+ buf, &obj);
+
+ tmy_free(buf);
+
+out: ;
+ if (!is_enforce)
+ error = 0;
+ return error;
+}
+
+/**
+ * tmy_single_write_perm - check permission for create(2) etc. operation.
+ * @operation: operation index number.
+ * @dentry: pointer to "struct dentry".
+ * @mnt: pointer to "struct vfsmount".
+ *
+ * Returns zero if permission granted.
+ * Returns nonzero if permission denied.
+ */
+int tmy_single_write_perm(const unsigned int operation,
+ struct dentry *dentry,
+ struct vfsmount *mnt)
+{
+ struct obj_info obj;
+ int error = -ENOMEM;
+ struct path_info *buf;
+ const u8 is_enforce = tmy_enforce(TMY_MAC_FOR_FILE);
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+
+ buf = tmy_get_path(dentry, mnt);
+
+ if (!buf)
+ goto out;
+
+ memset(&obj, 0, sizeof(obj));
+ obj.path1_dentry = dentry;
+ obj.path1_vfsmnt = mnt;
+
+ switch (operation) {
+ case TMY_TYPE_MKDIR_ACL:
+ case TMY_TYPE_RMDIR_ACL:
+ if (!buf->is_dir) {
+ strcat((char *) buf->name, "/");
+ tmy_fill_path_info(buf);
+ }
+ }
+ error = tmy_single_write_perm2(operation, buf, &obj);
+ tmy_free(buf);
+
+out: ;
+ if (!is_enforce)
+ error = 0;
+
+ return error;
+}
+
+/**
+ * tmy_rewrite_perm - check permission for truncate/overwrite operation.
+ * @filp: pointer to "struct file".
+ *
+ * Returns zero if permission granted.
+ * Returns nonzero if permission denied.
+ */
+int tmy_rewrite_perm(struct file *filp)
+{
+ int error = -ENOMEM;
+ const u8 is_enforce = tmy_enforce(TMY_MAC_FOR_FILE);
+ struct path_info *buf = tmy_get_path(filp->f_dentry, filp->f_vfsmnt);
+
+ if (!buf)
+ goto out;
+
+ if (tmy_is_no_rewrite_file(buf)) {
+ struct obj_info obj;
+ memset(&obj, 0, sizeof(obj));
+ obj.path1_dentry = filp->f_dentry;
+ obj.path1_vfsmnt = filp->f_vfsmnt;
+ error = tmy_single_write_perm2(TMY_TYPE_REWRITE_ACL,
+ buf, &obj);
+ } else
+ error = 0;
+
+ tmy_free(buf);
+
+out: ;
+ if (!is_enforce)
+ error = 0;
+ return error;
+}
+
+/**
+ * tmy_double_write_perm - check permission for link(2)/rename(2) operation.
+ * @operation: operation index number.
+ * @dentry1: pointer to "struct dentry".
+ * @mnt1: pointer to "struct vfsmount".
+ * @dentry2: pointer to "struct dentry".
+ * @mnt2: pointer to "struct vfsmount".
+ *
+ * Returns zero if permission granted.
+ * Returns nonzero if permission denied.
+ */
+int tmy_double_write_perm(const unsigned int operation,
+ struct dentry *dentry1,
+ struct vfsmount *mnt1,
+ struct dentry *dentry2,
+ struct vfsmount *mnt2)
+{
+ struct obj_info obj;
+ int error = -ENOMEM;
+ struct path_info *buf1;
+ struct path_info *buf2;
+ struct domain_info * const domain = TMY_SECURITY->domain;
+ const u8 is_enforce = tmy_enforce(TMY_MAC_FOR_FILE);
+
+ if (!tmy_flags(TMY_MAC_FOR_FILE))
+ return 0;
+ buf1 = tmy_get_path(dentry1, mnt1);
+ buf2 = tmy_get_path(dentry2, mnt2);
+
+ if (!buf1 || !buf2)
+ goto out;
+
+ memset(&obj, 0, sizeof(obj));
+ obj.path1_dentry = dentry1;
+ obj.path1_vfsmnt = mnt1;
+ obj.path2_dentry = dentry2;
+ obj.path2_vfsmnt = mnt2;
+ if (operation == TMY_TYPE_RENAME_ACL) {
+ /* TMY_TYPE_LINK_ACL can't reach here for directory. */
+ if (dentry1->d_inode && S_ISDIR(dentry1->d_inode->i_mode)) {
+ if (!buf1->is_dir) {
+ strcat((char *) buf1->name, "/");
+ tmy_fill_path_info(buf1);
+ }
+ if (!buf2->is_dir) {
+ strcat((char *) buf2->name, "/");
+ tmy_fill_path_info(buf2);
+ }
+ }
+ }
+ error = tmy_double_write_acl(operation, buf1, buf2, &obj);
+
+ tmy_audit_write_log(tmy_acltype2keyword(operation),
+ buf1, buf2, !error, is_enforce);
+
+ if (!error)
+ goto out;
+
+ if (is_enforce)
+ error = tmy_supervisor("%s\nallow_%s %s %s\n",
+ domain->domainname->name,
+ tmy_acltype2keyword(operation),
+ buf1->name, buf2->name);
+ else if (tmy_accept(TMY_MAC_FOR_FILE, domain))
+ tmy_add_double_write_acl(operation,
+ tmy_get_pattern(buf1)->name,
+ tmy_get_pattern(buf2)->name,
+ domain, NULL, 0);
+
+out: ;
+ tmy_free(buf1);
+ tmy_free(buf2);
+ if (!is_enforce)
+ error = 0;
+ return error;
+}
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