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Diffstat (limited to 'security/apparmor/apparmorfs.c')
| -rw-r--r-- | security/apparmor/apparmorfs.c | 2698 |
1 files changed, 2698 insertions, 0 deletions
diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c new file mode 100644 index 0000000000..63ddefb6dd --- /dev/null +++ b/security/apparmor/apparmorfs.c @@ -0,0 +1,2698 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AppArmor security module + * + * This file contains AppArmor /sys/kernel/security/apparmor interface functions + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + */ + +#include <linux/ctype.h> +#include <linux/security.h> +#include <linux/vmalloc.h> +#include <linux/init.h> +#include <linux/seq_file.h> +#include <linux/uaccess.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/capability.h> +#include <linux/rcupdate.h> +#include <linux/fs.h> +#include <linux/fs_context.h> +#include <linux/poll.h> +#include <linux/zstd.h> +#include <uapi/linux/major.h> +#include <uapi/linux/magic.h> + +#include "include/apparmor.h" +#include "include/apparmorfs.h" +#include "include/audit.h" +#include "include/cred.h" +#include "include/crypto.h" +#include "include/ipc.h" +#include "include/label.h" +#include "include/policy.h" +#include "include/policy_ns.h" +#include "include/resource.h" +#include "include/policy_unpack.h" +#include "include/task.h" + +/* + * The apparmor filesystem interface used for policy load and introspection + * The interface is split into two main components based on their function + * a securityfs component: + * used for static files that are always available, and which allows + * userspace to specificy the location of the security filesystem. + * + * fns and data are prefixed with + * aa_sfs_ + * + * an apparmorfs component: + * used loaded policy content and introspection. It is not part of a + * regular mounted filesystem and is available only through the magic + * policy symlink in the root of the securityfs apparmor/ directory. + * Tasks queries will be magically redirected to the correct portion + * of the policy tree based on their confinement. + * + * fns and data are prefixed with + * aafs_ + * + * The aa_fs_ prefix is used to indicate the fn is used by both the + * securityfs and apparmorfs filesystems. + */ + + +/* + * support fns + */ + +struct rawdata_f_data { + struct aa_loaddata *loaddata; +}; + +#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY +#define RAWDATA_F_DATA_BUF(p) (char *)(p + 1) + +static void rawdata_f_data_free(struct rawdata_f_data *private) +{ + if (!private) + return; + + aa_put_loaddata(private->loaddata); + kvfree(private); +} + +static struct rawdata_f_data *rawdata_f_data_alloc(size_t size) +{ + struct rawdata_f_data *ret; + + if (size > SIZE_MAX - sizeof(*ret)) + return ERR_PTR(-EINVAL); + + ret = kvzalloc(sizeof(*ret) + size, GFP_KERNEL); + if (!ret) + return ERR_PTR(-ENOMEM); + + return ret; +} +#endif + +/** + * mangle_name - mangle a profile name to std profile layout form + * @name: profile name to mangle (NOT NULL) + * @target: buffer to store mangled name, same length as @name (MAYBE NULL) + * + * Returns: length of mangled name + */ +static int mangle_name(const char *name, char *target) +{ + char *t = target; + + while (*name == '/' || *name == '.') + name++; + + if (target) { + for (; *name; name++) { + if (*name == '/') + *(t)++ = '.'; + else if (isspace(*name)) + *(t)++ = '_'; + else if (isalnum(*name) || strchr("._-", *name)) + *(t)++ = *name; + } + + *t = 0; + } else { + int len = 0; + for (; *name; name++) { + if (isalnum(*name) || isspace(*name) || + strchr("/._-", *name)) + len++; + } + + return len; + } + + return t - target; +} + + +/* + * aafs - core fns and data for the policy tree + */ + +#define AAFS_NAME "apparmorfs" +static struct vfsmount *aafs_mnt; +static int aafs_count; + + +static int aafs_show_path(struct seq_file *seq, struct dentry *dentry) +{ + seq_printf(seq, "%s:[%lu]", AAFS_NAME, d_inode(dentry)->i_ino); + return 0; +} + +static void aafs_free_inode(struct inode *inode) +{ + if (S_ISLNK(inode->i_mode)) + kfree(inode->i_link); + free_inode_nonrcu(inode); +} + +static const struct super_operations aafs_super_ops = { + .statfs = simple_statfs, + .free_inode = aafs_free_inode, + .show_path = aafs_show_path, +}; + +static int apparmorfs_fill_super(struct super_block *sb, struct fs_context *fc) +{ + static struct tree_descr files[] = { {""} }; + int error; + + error = simple_fill_super(sb, AAFS_MAGIC, files); + if (error) + return error; + sb->s_op = &aafs_super_ops; + + return 0; +} + +static int apparmorfs_get_tree(struct fs_context *fc) +{ + return get_tree_single(fc, apparmorfs_fill_super); +} + +static const struct fs_context_operations apparmorfs_context_ops = { + .get_tree = apparmorfs_get_tree, +}; + +static int apparmorfs_init_fs_context(struct fs_context *fc) +{ + fc->ops = &apparmorfs_context_ops; + return 0; +} + +static struct file_system_type aafs_ops = { + .owner = THIS_MODULE, + .name = AAFS_NAME, + .init_fs_context = apparmorfs_init_fs_context, + .kill_sb = kill_anon_super, +}; + +/** + * __aafs_setup_d_inode - basic inode setup for apparmorfs + * @dir: parent directory for the dentry + * @dentry: dentry we are seting the inode up for + * @mode: permissions the file should have + * @data: data to store on inode.i_private, available in open() + * @link: if symlink, symlink target string + * @fops: struct file_operations that should be used + * @iops: struct of inode_operations that should be used + */ +static int __aafs_setup_d_inode(struct inode *dir, struct dentry *dentry, + umode_t mode, void *data, char *link, + const struct file_operations *fops, + const struct inode_operations *iops) +{ + struct inode *inode = new_inode(dir->i_sb); + + AA_BUG(!dir); + AA_BUG(!dentry); + + if (!inode) + return -ENOMEM; + + inode->i_ino = get_next_ino(); + inode->i_mode = mode; + inode->i_atime = inode->i_mtime = inode_set_ctime_current(inode); + inode->i_private = data; + if (S_ISDIR(mode)) { + inode->i_op = iops ? iops : &simple_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + inc_nlink(inode); + inc_nlink(dir); + } else if (S_ISLNK(mode)) { + inode->i_op = iops ? iops : &simple_symlink_inode_operations; + inode->i_link = link; + } else { + inode->i_fop = fops; + } + d_instantiate(dentry, inode); + dget(dentry); + + return 0; +} + +/** + * aafs_create - create a dentry in the apparmorfs filesystem + * + * @name: name of dentry to create + * @mode: permissions the file should have + * @parent: parent directory for this dentry + * @data: data to store on inode.i_private, available in open() + * @link: if symlink, symlink target string + * @fops: struct file_operations that should be used for + * @iops: struct of inode_operations that should be used + * + * This is the basic "create a xxx" function for apparmorfs. + * + * Returns a pointer to a dentry if it succeeds, that must be free with + * aafs_remove(). Will return ERR_PTR on failure. + */ +static struct dentry *aafs_create(const char *name, umode_t mode, + struct dentry *parent, void *data, void *link, + const struct file_operations *fops, + const struct inode_operations *iops) +{ + struct dentry *dentry; + struct inode *dir; + int error; + + AA_BUG(!name); + AA_BUG(!parent); + + if (!(mode & S_IFMT)) + mode = (mode & S_IALLUGO) | S_IFREG; + + error = simple_pin_fs(&aafs_ops, &aafs_mnt, &aafs_count); + if (error) + return ERR_PTR(error); + + dir = d_inode(parent); + + inode_lock(dir); + dentry = lookup_one_len(name, parent, strlen(name)); + if (IS_ERR(dentry)) { + error = PTR_ERR(dentry); + goto fail_lock; + } + + if (d_really_is_positive(dentry)) { + error = -EEXIST; + goto fail_dentry; + } + + error = __aafs_setup_d_inode(dir, dentry, mode, data, link, fops, iops); + if (error) + goto fail_dentry; + inode_unlock(dir); + + return dentry; + +fail_dentry: + dput(dentry); + +fail_lock: + inode_unlock(dir); + simple_release_fs(&aafs_mnt, &aafs_count); + + return ERR_PTR(error); +} + +/** + * aafs_create_file - create a file in the apparmorfs filesystem + * + * @name: name of dentry to create + * @mode: permissions the file should have + * @parent: parent directory for this dentry + * @data: data to store on inode.i_private, available in open() + * @fops: struct file_operations that should be used for + * + * see aafs_create + */ +static struct dentry *aafs_create_file(const char *name, umode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fops) +{ + return aafs_create(name, mode, parent, data, NULL, fops, NULL); +} + +/** + * aafs_create_dir - create a directory in the apparmorfs filesystem + * + * @name: name of dentry to create + * @parent: parent directory for this dentry + * + * see aafs_create + */ +static struct dentry *aafs_create_dir(const char *name, struct dentry *parent) +{ + return aafs_create(name, S_IFDIR | 0755, parent, NULL, NULL, NULL, + NULL); +} + +/** + * aafs_remove - removes a file or directory from the apparmorfs filesystem + * + * @dentry: dentry of the file/directory/symlink to removed. + */ +static void aafs_remove(struct dentry *dentry) +{ + struct inode *dir; + + if (!dentry || IS_ERR(dentry)) + return; + + dir = d_inode(dentry->d_parent); + inode_lock(dir); + if (simple_positive(dentry)) { + if (d_is_dir(dentry)) + simple_rmdir(dir, dentry); + else + simple_unlink(dir, dentry); + d_delete(dentry); + dput(dentry); + } + inode_unlock(dir); + simple_release_fs(&aafs_mnt, &aafs_count); +} + + +/* + * aa_fs - policy load/replace/remove + */ + +/** + * aa_simple_write_to_buffer - common routine for getting policy from user + * @userbuf: user buffer to copy data from (NOT NULL) + * @alloc_size: size of user buffer (REQUIRES: @alloc_size >= @copy_size) + * @copy_size: size of data to copy from user buffer + * @pos: position write is at in the file (NOT NULL) + * + * Returns: kernel buffer containing copy of user buffer data or an + * ERR_PTR on failure. + */ +static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf, + size_t alloc_size, + size_t copy_size, + loff_t *pos) +{ + struct aa_loaddata *data; + + AA_BUG(copy_size > alloc_size); + + if (*pos != 0) + /* only writes from pos 0, that is complete writes */ + return ERR_PTR(-ESPIPE); + + /* freed by caller to simple_write_to_buffer */ + data = aa_loaddata_alloc(alloc_size); + if (IS_ERR(data)) + return data; + + data->size = copy_size; + if (copy_from_user(data->data, userbuf, copy_size)) { + aa_put_loaddata(data); + return ERR_PTR(-EFAULT); + } + + return data; +} + +static ssize_t policy_update(u32 mask, const char __user *buf, size_t size, + loff_t *pos, struct aa_ns *ns) +{ + struct aa_loaddata *data; + struct aa_label *label; + ssize_t error; + + label = begin_current_label_crit_section(); + + /* high level check about policy management - fine grained in + * below after unpack + */ + error = aa_may_manage_policy(current_cred(), label, ns, mask); + if (error) + goto end_section; + + data = aa_simple_write_to_buffer(buf, size, size, pos); + error = PTR_ERR(data); + if (!IS_ERR(data)) { + error = aa_replace_profiles(ns, label, mask, data); + aa_put_loaddata(data); + } +end_section: + end_current_label_crit_section(label); + + return error; +} + +/* .load file hook fn to load policy */ +static ssize_t profile_load(struct file *f, const char __user *buf, size_t size, + loff_t *pos) +{ + struct aa_ns *ns = aa_get_ns(f->f_inode->i_private); + int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns); + + aa_put_ns(ns); + + return error; +} + +static const struct file_operations aa_fs_profile_load = { + .write = profile_load, + .llseek = default_llseek, +}; + +/* .replace file hook fn to load and/or replace policy */ +static ssize_t profile_replace(struct file *f, const char __user *buf, + size_t size, loff_t *pos) +{ + struct aa_ns *ns = aa_get_ns(f->f_inode->i_private); + int error = policy_update(AA_MAY_LOAD_POLICY | AA_MAY_REPLACE_POLICY, + buf, size, pos, ns); + aa_put_ns(ns); + + return error; +} + +static const struct file_operations aa_fs_profile_replace = { + .write = profile_replace, + .llseek = default_llseek, +}; + +/* .remove file hook fn to remove loaded policy */ +static ssize_t profile_remove(struct file *f, const char __user *buf, + size_t size, loff_t *pos) +{ + struct aa_loaddata *data; + struct aa_label *label; + ssize_t error; + struct aa_ns *ns = aa_get_ns(f->f_inode->i_private); + + label = begin_current_label_crit_section(); + /* high level check about policy management - fine grained in + * below after unpack + */ + error = aa_may_manage_policy(current_cred(), label, ns, + AA_MAY_REMOVE_POLICY); + if (error) + goto out; + + /* + * aa_remove_profile needs a null terminated string so 1 extra + * byte is allocated and the copied data is null terminated. + */ + data = aa_simple_write_to_buffer(buf, size + 1, size, pos); + + error = PTR_ERR(data); + if (!IS_ERR(data)) { + data->data[size] = 0; + error = aa_remove_profiles(ns, label, data->data, size); + aa_put_loaddata(data); + } + out: + end_current_label_crit_section(label); + aa_put_ns(ns); + return error; +} + +static const struct file_operations aa_fs_profile_remove = { + .write = profile_remove, + .llseek = default_llseek, +}; + +struct aa_revision { + struct aa_ns *ns; + long last_read; +}; + +/* revision file hook fn for policy loads */ +static int ns_revision_release(struct inode *inode, struct file *file) +{ + struct aa_revision *rev = file->private_data; + + if (rev) { + aa_put_ns(rev->ns); + kfree(rev); + } + + return 0; +} + +static ssize_t ns_revision_read(struct file *file, char __user *buf, + size_t size, loff_t *ppos) +{ + struct aa_revision *rev = file->private_data; + char buffer[32]; + long last_read; + int avail; + + mutex_lock_nested(&rev->ns->lock, rev->ns->level); + last_read = rev->last_read; + if (last_read == rev->ns->revision) { + mutex_unlock(&rev->ns->lock); + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + if (wait_event_interruptible(rev->ns->wait, + last_read != + READ_ONCE(rev->ns->revision))) + return -ERESTARTSYS; + mutex_lock_nested(&rev->ns->lock, rev->ns->level); + } + + avail = sprintf(buffer, "%ld\n", rev->ns->revision); + if (*ppos + size > avail) { + rev->last_read = rev->ns->revision; + *ppos = 0; + } + mutex_unlock(&rev->ns->lock); + + return simple_read_from_buffer(buf, size, ppos, buffer, avail); +} + +static int ns_revision_open(struct inode *inode, struct file *file) +{ + struct aa_revision *rev = kzalloc(sizeof(*rev), GFP_KERNEL); + + if (!rev) + return -ENOMEM; + + rev->ns = aa_get_ns(inode->i_private); + if (!rev->ns) + rev->ns = aa_get_current_ns(); + file->private_data = rev; + + return 0; +} + +static __poll_t ns_revision_poll(struct file *file, poll_table *pt) +{ + struct aa_revision *rev = file->private_data; + __poll_t mask = 0; + + if (rev) { + mutex_lock_nested(&rev->ns->lock, rev->ns->level); + poll_wait(file, &rev->ns->wait, pt); + if (rev->last_read < rev->ns->revision) + mask |= EPOLLIN | EPOLLRDNORM; + mutex_unlock(&rev->ns->lock); + } + + return mask; +} + +void __aa_bump_ns_revision(struct aa_ns *ns) +{ + WRITE_ONCE(ns->revision, READ_ONCE(ns->revision) + 1); + wake_up_interruptible(&ns->wait); +} + +static const struct file_operations aa_fs_ns_revision_fops = { + .owner = THIS_MODULE, + .open = ns_revision_open, + .poll = ns_revision_poll, + .read = ns_revision_read, + .llseek = generic_file_llseek, + .release = ns_revision_release, +}; + +static void profile_query_cb(struct aa_profile *profile, struct aa_perms *perms, + const char *match_str, size_t match_len) +{ + struct aa_ruleset *rules = list_first_entry(&profile->rules, + typeof(*rules), list); + struct aa_perms tmp = { }; + aa_state_t state = DFA_NOMATCH; + + if (profile_unconfined(profile)) + return; + if (rules->file.dfa && *match_str == AA_CLASS_FILE) { + state = aa_dfa_match_len(rules->file.dfa, + rules->file.start[AA_CLASS_FILE], + match_str + 1, match_len - 1); + if (state) { + struct path_cond cond = { }; + + tmp = *(aa_lookup_fperms(&(rules->file), state, &cond)); + } + } else if (rules->policy.dfa) { + if (!RULE_MEDIATES(rules, *match_str)) + return; /* no change to current perms */ + state = aa_dfa_match_len(rules->policy.dfa, + rules->policy.start[0], + match_str, match_len); + if (state) + tmp = *aa_lookup_perms(&rules->policy, state); + } + aa_apply_modes_to_perms(profile, &tmp); + aa_perms_accum_raw(perms, &tmp); +} + + +/** + * query_data - queries a policy and writes its data to buf + * @buf: the resulting data is stored here (NOT NULL) + * @buf_len: size of buf + * @query: query string used to retrieve data + * @query_len: size of query including second NUL byte + * + * The buffers pointed to by buf and query may overlap. The query buffer is + * parsed before buf is written to. + * + * The query should look like "<LABEL>\0<KEY>\0", where <LABEL> is the name of + * the security confinement context and <KEY> is the name of the data to + * retrieve. <LABEL> and <KEY> must not be NUL-terminated. + * + * Don't expect the contents of buf to be preserved on failure. + * + * Returns: number of characters written to buf or -errno on failure + */ +static ssize_t query_data(char *buf, size_t buf_len, + char *query, size_t query_len) +{ + char *out; + const char *key; + struct label_it i; + struct aa_label *label, *curr; + struct aa_profile *profile; + struct aa_data *data; + u32 bytes, blocks; + __le32 outle32; + + if (!query_len) + return -EINVAL; /* need a query */ + + key = query + strnlen(query, query_len) + 1; + if (key + 1 >= query + query_len) + return -EINVAL; /* not enough space for a non-empty key */ + if (key + strnlen(key, query + query_len - key) >= query + query_len) + return -EINVAL; /* must end with NUL */ + + if (buf_len < sizeof(bytes) + sizeof(blocks)) + return -EINVAL; /* not enough space */ + + curr = begin_current_label_crit_section(); + label = aa_label_parse(curr, query, GFP_KERNEL, false, false); + end_current_label_crit_section(curr); + if (IS_ERR(label)) + return PTR_ERR(label); + + /* We are going to leave space for two numbers. The first is the total + * number of bytes we are writing after the first number. This is so + * users can read the full output without reallocation. + * + * The second number is the number of data blocks we're writing. An + * application might be confined by multiple policies having data in + * the same key. + */ + memset(buf, 0, sizeof(bytes) + sizeof(blocks)); + out = buf + sizeof(bytes) + sizeof(blocks); + + blocks = 0; + label_for_each_confined(i, label, profile) { + if (!profile->data) + continue; + + data = rhashtable_lookup_fast(profile->data, &key, + profile->data->p); + + if (data) { + if (out + sizeof(outle32) + data->size > buf + + buf_len) { + aa_put_label(label); + return -EINVAL; /* not enough space */ + } + outle32 = __cpu_to_le32(data->size); + memcpy(out, &outle32, sizeof(outle32)); + out += sizeof(outle32); + memcpy(out, data->data, data->size); + out += data->size; + blocks++; + } + } + aa_put_label(label); + + outle32 = __cpu_to_le32(out - buf - sizeof(bytes)); + memcpy(buf, &outle32, sizeof(outle32)); + outle32 = __cpu_to_le32(blocks); + memcpy(buf + sizeof(bytes), &outle32, sizeof(outle32)); + + return out - buf; +} + +/** + * query_label - queries a label and writes permissions to buf + * @buf: the resulting permissions string is stored here (NOT NULL) + * @buf_len: size of buf + * @query: binary query string to match against the dfa + * @query_len: size of query + * @view_only: only compute for querier's view + * + * The buffers pointed to by buf and query may overlap. The query buffer is + * parsed before buf is written to. + * + * The query should look like "LABEL_NAME\0DFA_STRING" where LABEL_NAME is + * the name of the label, in the current namespace, that is to be queried and + * DFA_STRING is a binary string to match against the label(s)'s DFA. + * + * LABEL_NAME must be NUL terminated. DFA_STRING may contain NUL characters + * but must *not* be NUL terminated. + * + * Returns: number of characters written to buf or -errno on failure + */ +static ssize_t query_label(char *buf, size_t buf_len, + char *query, size_t query_len, bool view_only) +{ + struct aa_profile *profile; + struct aa_label *label, *curr; + char *label_name, *match_str; + size_t label_name_len, match_len; + struct aa_perms perms; + struct label_it i; + + if (!query_len) + return -EINVAL; + + label_name = query; + label_name_len = strnlen(query, query_len); + if (!label_name_len || label_name_len == query_len) + return -EINVAL; + + /** + * The extra byte is to account for the null byte between the + * profile name and dfa string. profile_name_len is greater + * than zero and less than query_len, so a byte can be safely + * added or subtracted. + */ + match_str = label_name + label_name_len + 1; + match_len = query_len - label_name_len - 1; + + curr = begin_current_label_crit_section(); + label = aa_label_parse(curr, label_name, GFP_KERNEL, false, false); + end_current_label_crit_section(curr); + if (IS_ERR(label)) + return PTR_ERR(label); + + perms = allperms; + if (view_only) { + label_for_each_in_ns(i, labels_ns(label), label, profile) { + profile_query_cb(profile, &perms, match_str, match_len); + } + } else { + label_for_each(i, label, profile) { + profile_query_cb(profile, &perms, match_str, match_len); + } + } + aa_put_label(label); + + return scnprintf(buf, buf_len, + "allow 0x%08x\ndeny 0x%08x\naudit 0x%08x\nquiet 0x%08x\n", + perms.allow, perms.deny, perms.audit, perms.quiet); +} + +/* + * Transaction based IO. + * The file expects a write which triggers the transaction, and then + * possibly a read(s) which collects the result - which is stored in a + * file-local buffer. Once a new write is performed, a new set of results + * are stored in the file-local buffer. + */ +struct multi_transaction { + struct kref count; + ssize_t size; + char data[]; +}; + +#define MULTI_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct multi_transaction)) + +static void multi_transaction_kref(struct kref *kref) +{ + struct multi_transaction *t; + + t = container_of(kref, struct multi_transaction, count); + free_page((unsigned long) t); +} + +static struct multi_transaction * +get_multi_transaction(struct multi_transaction *t) +{ + if (t) + kref_get(&(t->count)); + + return t; +} + +static void put_multi_transaction(struct multi_transaction *t) +{ + if (t) + kref_put(&(t->count), multi_transaction_kref); +} + +/* does not increment @new's count */ +static void multi_transaction_set(struct file *file, + struct multi_transaction *new, size_t n) +{ + struct multi_transaction *old; + + AA_BUG(n > MULTI_TRANSACTION_LIMIT); + + new->size = n; + spin_lock(&file->f_lock); + old = (struct multi_transaction *) file->private_data; + file->private_data = new; + spin_unlock(&file->f_lock); + put_multi_transaction(old); +} + +static struct multi_transaction *multi_transaction_new(struct file *file, + const char __user *buf, + size_t size) +{ + struct multi_transaction *t; + + if (size > MULTI_TRANSACTION_LIMIT - 1) + return ERR_PTR(-EFBIG); + + t = (struct multi_transaction *)get_zeroed_page(GFP_KERNEL); + if (!t) + return ERR_PTR(-ENOMEM); + kref_init(&t->count); + if (copy_from_user(t->data, buf, size)) { + put_multi_transaction(t); + return ERR_PTR(-EFAULT); + } + + return t; +} + +static ssize_t multi_transaction_read(struct file *file, char __user *buf, + size_t size, loff_t *pos) +{ + struct multi_transaction *t; + ssize_t ret; + + spin_lock(&file->f_lock); + t = get_multi_transaction(file->private_data); + spin_unlock(&file->f_lock); + + if (!t) + return 0; + + ret = simple_read_from_buffer(buf, size, pos, t->data, t->size); + put_multi_transaction(t); + + return ret; +} + +static int multi_transaction_release(struct inode *inode, struct file *file) +{ + put_multi_transaction(file->private_data); + + return 0; +} + +#define QUERY_CMD_LABEL "label\0" +#define QUERY_CMD_LABEL_LEN 6 +#define QUERY_CMD_PROFILE "profile\0" +#define QUERY_CMD_PROFILE_LEN 8 +#define QUERY_CMD_LABELALL "labelall\0" +#define QUERY_CMD_LABELALL_LEN 9 +#define QUERY_CMD_DATA "data\0" +#define QUERY_CMD_DATA_LEN 5 + +/** + * aa_write_access - generic permissions and data query + * @file: pointer to open apparmorfs/access file + * @ubuf: user buffer containing the complete query string (NOT NULL) + * @count: size of ubuf + * @ppos: position in the file (MUST BE ZERO) + * + * Allows for one permissions or data query per open(), write(), and read() + * sequence. The only queries currently supported are label-based queries for + * permissions or data. + * + * For permissions queries, ubuf must begin with "label\0", followed by the + * profile query specific format described in the query_label() function + * documentation. + * + * For data queries, ubuf must have the form "data\0<LABEL>\0<KEY>\0", where + * <LABEL> is the name of the security confinement context and <KEY> is the + * name of the data to retrieve. + * + * Returns: number of bytes written or -errno on failure + */ +static ssize_t aa_write_access(struct file *file, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct multi_transaction *t; + ssize_t len; + + if (*ppos) + return -ESPIPE; + + t = multi_transaction_new(file, ubuf, count); + if (IS_ERR(t)) + return PTR_ERR(t); + + if (count > QUERY_CMD_PROFILE_LEN && + !memcmp(t->data, QUERY_CMD_PROFILE, QUERY_CMD_PROFILE_LEN)) { + len = query_label(t->data, MULTI_TRANSACTION_LIMIT, + t->data + QUERY_CMD_PROFILE_LEN, + count - QUERY_CMD_PROFILE_LEN, true); + } else if (count > QUERY_CMD_LABEL_LEN && + !memcmp(t->data, QUERY_CMD_LABEL, QUERY_CMD_LABEL_LEN)) { + len = query_label(t->data, MULTI_TRANSACTION_LIMIT, + t->data + QUERY_CMD_LABEL_LEN, + count - QUERY_CMD_LABEL_LEN, true); + } else if (count > QUERY_CMD_LABELALL_LEN && + !memcmp(t->data, QUERY_CMD_LABELALL, + QUERY_CMD_LABELALL_LEN)) { + len = query_label(t->data, MULTI_TRANSACTION_LIMIT, + t->data + QUERY_CMD_LABELALL_LEN, + count - QUERY_CMD_LABELALL_LEN, false); + } else if (count > QUERY_CMD_DATA_LEN && + !memcmp(t->data, QUERY_CMD_DATA, QUERY_CMD_DATA_LEN)) { + len = query_data(t->data, MULTI_TRANSACTION_LIMIT, + t->data + QUERY_CMD_DATA_LEN, + count - QUERY_CMD_DATA_LEN); + } else + len = -EINVAL; + + if (len < 0) { + put_multi_transaction(t); + return len; + } + + multi_transaction_set(file, t, len); + + return count; +} + +static const struct file_operations aa_sfs_access = { + .write = aa_write_access, + .read = multi_transaction_read, + .release = multi_transaction_release, + .llseek = generic_file_llseek, +}; + +static int aa_sfs_seq_show(struct seq_file *seq, void *v) +{ + struct aa_sfs_entry *fs_file = seq->private; + + if (!fs_file) + return 0; + + switch (fs_file->v_type) { + case AA_SFS_TYPE_BOOLEAN: + seq_printf(seq, "%s\n", fs_file->v.boolean ? "yes" : "no"); + break; + case AA_SFS_TYPE_STRING: + seq_printf(seq, "%s\n", fs_file->v.string); + break; + case AA_SFS_TYPE_U64: + seq_printf(seq, "%#08lx\n", fs_file->v.u64); + break; + default: + /* Ignore unpritable entry types. */ + break; + } + + return 0; +} + +static int aa_sfs_seq_open(struct inode *inode, struct file *file) +{ + return single_open(file, aa_sfs_seq_show, inode->i_private); +} + +const struct file_operations aa_sfs_seq_file_ops = { + .owner = THIS_MODULE, + .open = aa_sfs_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/* + * profile based file operations + * policy/profiles/XXXX/profiles/ * + */ + +#define SEQ_PROFILE_FOPS(NAME) \ +static int seq_profile_ ##NAME ##_open(struct inode *inode, struct file *file)\ +{ \ + return seq_profile_open(inode, file, seq_profile_ ##NAME ##_show); \ +} \ + \ +static const struct file_operations seq_profile_ ##NAME ##_fops = { \ + .owner = THIS_MODULE, \ + .open = seq_profile_ ##NAME ##_open, \ + .read = seq_read, \ + .llseek = seq_lseek, \ + .release = seq_profile_release, \ +} \ + +static int seq_profile_open(struct inode *inode, struct file *file, + int (*show)(struct seq_file *, void *)) +{ + struct aa_proxy *proxy = aa_get_proxy(inode->i_private); + int error = single_open(file, show, proxy); + + if (error) { + file->private_data = NULL; + aa_put_proxy(proxy); + } + + return error; +} + +static int seq_profile_release(struct inode *inode, struct file *file) +{ + struct seq_file *seq = (struct seq_file *) file->private_data; + if (seq) + aa_put_proxy(seq->private); + return single_release(inode, file); +} + +static int seq_profile_name_show(struct seq_file *seq, void *v) +{ + struct aa_proxy *proxy = seq->private; + struct aa_label *label = aa_get_label_rcu(&proxy->label); + struct aa_profile *profile = labels_profile(label); + seq_printf(seq, "%s\n", profile->base.name); + aa_put_label(label); + + return 0; +} + +static int seq_profile_mode_show(struct seq_file *seq, void *v) +{ + struct aa_proxy *proxy = seq->private; + struct aa_label *label = aa_get_label_rcu(&proxy->label); + struct aa_profile *profile = labels_profile(label); + seq_printf(seq, "%s\n", aa_profile_mode_names[profile->mode]); + aa_put_label(label); + + return 0; +} + +static int seq_profile_attach_show(struct seq_file *seq, void *v) +{ + struct aa_proxy *proxy = seq->private; + struct aa_label *label = aa_get_label_rcu(&proxy->label); + struct aa_profile *profile = labels_profile(label); + if (profile->attach.xmatch_str) + seq_printf(seq, "%s\n", profile->attach.xmatch_str); + else if (profile->attach.xmatch.dfa) + seq_puts(seq, "<unknown>\n"); + else + seq_printf(seq, "%s\n", profile->base.name); + aa_put_label(label); + + return 0; +} + +static int seq_profile_hash_show(struct seq_file *seq, void *v) +{ + struct aa_proxy *proxy = seq->private; + struct aa_label *label = aa_get_label_rcu(&proxy->label); + struct aa_profile *profile = labels_profile(label); + unsigned int i, size = aa_hash_size(); + + if (profile->hash) { + for (i = 0; i < size; i++) + seq_printf(seq, "%.2x", profile->hash[i]); + seq_putc(seq, '\n'); + } + aa_put_label(label); + + return 0; +} + +SEQ_PROFILE_FOPS(name); +SEQ_PROFILE_FOPS(mode); +SEQ_PROFILE_FOPS(attach); +SEQ_PROFILE_FOPS(hash); + +/* + * namespace based files + * several root files and + * policy/ * + */ + +#define SEQ_NS_FOPS(NAME) \ +static int seq_ns_ ##NAME ##_open(struct inode *inode, struct file *file) \ +{ \ + return single_open(file, seq_ns_ ##NAME ##_show, inode->i_private); \ +} \ + \ +static const struct file_operations seq_ns_ ##NAME ##_fops = { \ + .owner = THIS_MODULE, \ + .open = seq_ns_ ##NAME ##_open, \ + .read = seq_read, \ + .llseek = seq_lseek, \ + .release = single_release, \ +} \ + +static int seq_ns_stacked_show(struct seq_file *seq, void *v) +{ + struct aa_label *label; + + label = begin_current_label_crit_section(); + seq_printf(seq, "%s\n", label->size > 1 ? "yes" : "no"); + end_current_label_crit_section(label); + + return 0; +} + +static int seq_ns_nsstacked_show(struct seq_file *seq, void *v) +{ + struct aa_label *label; + struct aa_profile *profile; + struct label_it it; + int count = 1; + + label = begin_current_label_crit_section(); + + if (label->size > 1) { + label_for_each(it, label, profile) + if (profile->ns != labels_ns(label)) { + count++; + break; + } + } + + seq_printf(seq, "%s\n", count > 1 ? "yes" : "no"); + end_current_label_crit_section(label); + + return 0; +} + +static int seq_ns_level_show(struct seq_file *seq, void *v) +{ + struct aa_label *label; + + label = begin_current_label_crit_section(); + seq_printf(seq, "%d\n", labels_ns(label)->level); + end_current_label_crit_section(label); + + return 0; +} + +static int seq_ns_name_show(struct seq_file *seq, void *v) +{ + struct aa_label *label = begin_current_label_crit_section(); + seq_printf(seq, "%s\n", labels_ns(label)->base.name); + end_current_label_crit_section(label); + + return 0; +} + +static int seq_ns_compress_min_show(struct seq_file *seq, void *v) +{ + seq_printf(seq, "%d\n", AA_MIN_CLEVEL); + return 0; +} + +static int seq_ns_compress_max_show(struct seq_file *seq, void *v) +{ + seq_printf(seq, "%d\n", AA_MAX_CLEVEL); + return 0; +} + +SEQ_NS_FOPS(stacked); +SEQ_NS_FOPS(nsstacked); +SEQ_NS_FOPS(level); +SEQ_NS_FOPS(name); +SEQ_NS_FOPS(compress_min); +SEQ_NS_FOPS(compress_max); + + +/* policy/raw_data/ * file ops */ +#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY +#define SEQ_RAWDATA_FOPS(NAME) \ +static int seq_rawdata_ ##NAME ##_open(struct inode *inode, struct file *file)\ +{ \ + return seq_rawdata_open(inode, file, seq_rawdata_ ##NAME ##_show); \ +} \ + \ +static const struct file_operations seq_rawdata_ ##NAME ##_fops = { \ + .owner = THIS_MODULE, \ + .open = seq_rawdata_ ##NAME ##_open, \ + .read = seq_read, \ + .llseek = seq_lseek, \ + .release = seq_rawdata_release, \ +} \ + +static int seq_rawdata_open(struct inode *inode, struct file *file, + int (*show)(struct seq_file *, void *)) +{ + struct aa_loaddata *data = __aa_get_loaddata(inode->i_private); + int error; + + if (!data) + /* lost race this ent is being reaped */ + return -ENOENT; + + error = single_open(file, show, data); + if (error) { + AA_BUG(file->private_data && + ((struct seq_file *)file->private_data)->private); + aa_put_loaddata(data); + } + + return error; +} + +static int seq_rawdata_release(struct inode *inode, struct file *file) +{ + struct seq_file *seq = (struct seq_file *) file->private_data; + + if (seq) + aa_put_loaddata(seq->private); + + return single_release(inode, file); +} + +static int seq_rawdata_abi_show(struct seq_file *seq, void *v) +{ + struct aa_loaddata *data = seq->private; + + seq_printf(seq, "v%d\n", data->abi); + + return 0; +} + +static int seq_rawdata_revision_show(struct seq_file *seq, void *v) +{ + struct aa_loaddata *data = seq->private; + + seq_printf(seq, "%ld\n", data->revision); + + return 0; +} + +static int seq_rawdata_hash_show(struct seq_file *seq, void *v) +{ + struct aa_loaddata *data = seq->private; + unsigned int i, size = aa_hash_size(); + + if (data->hash) { + for (i = 0; i < size; i++) + seq_printf(seq, "%.2x", data->hash[i]); + seq_putc(seq, '\n'); + } + + return 0; +} + +static int seq_rawdata_compressed_size_show(struct seq_file *seq, void *v) +{ + struct aa_loaddata *data = seq->private; + + seq_printf(seq, "%zu\n", data->compressed_size); + + return 0; +} + +SEQ_RAWDATA_FOPS(abi); +SEQ_RAWDATA_FOPS(revision); +SEQ_RAWDATA_FOPS(hash); +SEQ_RAWDATA_FOPS(compressed_size); + +static int decompress_zstd(char *src, size_t slen, char *dst, size_t dlen) +{ +#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY + if (slen < dlen) { + const size_t wksp_len = zstd_dctx_workspace_bound(); + zstd_dctx *ctx; + void *wksp; + size_t out_len; + int ret = 0; + + wksp = kvzalloc(wksp_len, GFP_KERNEL); + if (!wksp) { + ret = -ENOMEM; + goto cleanup; + } + ctx = zstd_init_dctx(wksp, wksp_len); + if (ctx == NULL) { + ret = -ENOMEM; + goto cleanup; + } + out_len = zstd_decompress_dctx(ctx, dst, dlen, src, slen); + if (zstd_is_error(out_len)) { + ret = -EINVAL; + goto cleanup; + } +cleanup: + kvfree(wksp); + return ret; + } +#endif + + if (dlen < slen) + return -EINVAL; + memcpy(dst, src, slen); + return 0; +} + +static ssize_t rawdata_read(struct file *file, char __user *buf, size_t size, + loff_t *ppos) +{ + struct rawdata_f_data *private = file->private_data; + + return simple_read_from_buffer(buf, size, ppos, + RAWDATA_F_DATA_BUF(private), + private->loaddata->size); +} + +static int rawdata_release(struct inode *inode, struct file *file) +{ + rawdata_f_data_free(file->private_data); + + return 0; +} + +static int rawdata_open(struct inode *inode, struct file *file) +{ + int error; + struct aa_loaddata *loaddata; + struct rawdata_f_data *private; + + if (!aa_current_policy_view_capable(NULL)) + return -EACCES; + + loaddata = __aa_get_loaddata(inode->i_private); + if (!loaddata) + /* lost race: this entry is being reaped */ + return -ENOENT; + + private = rawdata_f_data_alloc(loaddata->size); + if (IS_ERR(private)) { + error = PTR_ERR(private); + goto fail_private_alloc; + } + + private->loaddata = loaddata; + + error = decompress_zstd(loaddata->data, loaddata->compressed_size, + RAWDATA_F_DATA_BUF(private), + loaddata->size); + if (error) + goto fail_decompress; + + file->private_data = private; + return 0; + +fail_decompress: + rawdata_f_data_free(private); + return error; + +fail_private_alloc: + aa_put_loaddata(loaddata); + return error; +} + +static const struct file_operations rawdata_fops = { + .open = rawdata_open, + .read = rawdata_read, + .llseek = generic_file_llseek, + .release = rawdata_release, +}; + +static void remove_rawdata_dents(struct aa_loaddata *rawdata) +{ + int i; + + for (i = 0; i < AAFS_LOADDATA_NDENTS; i++) { + if (!IS_ERR_OR_NULL(rawdata->dents[i])) { + /* no refcounts on i_private */ + aafs_remove(rawdata->dents[i]); + rawdata->dents[i] = NULL; + } + } +} + +void __aa_fs_remove_rawdata(struct aa_loaddata *rawdata) +{ + AA_BUG(rawdata->ns && !mutex_is_locked(&rawdata->ns->lock)); + + if (rawdata->ns) { + remove_rawdata_dents(rawdata); + list_del_init(&rawdata->list); + aa_put_ns(rawdata->ns); + rawdata->ns = NULL; + } +} + +int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata) +{ + struct dentry *dent, *dir; + + AA_BUG(!ns); + AA_BUG(!rawdata); + AA_BUG(!mutex_is_locked(&ns->lock)); + AA_BUG(!ns_subdata_dir(ns)); + + /* + * just use ns revision dir was originally created at. This is + * under ns->lock and if load is successful revision will be + * bumped and is guaranteed to be unique + */ + rawdata->name = kasprintf(GFP_KERNEL, "%ld", ns->revision); + if (!rawdata->name) + return -ENOMEM; + + dir = aafs_create_dir(rawdata->name, ns_subdata_dir(ns)); + if (IS_ERR(dir)) + /* ->name freed when rawdata freed */ + return PTR_ERR(dir); + rawdata->dents[AAFS_LOADDATA_DIR] = dir; + + dent = aafs_create_file("abi", S_IFREG | 0444, dir, rawdata, + &seq_rawdata_abi_fops); + if (IS_ERR(dent)) + goto fail; + rawdata->dents[AAFS_LOADDATA_ABI] = dent; + + dent = aafs_create_file("revision", S_IFREG | 0444, dir, rawdata, + &seq_rawdata_revision_fops); + if (IS_ERR(dent)) + goto fail; + rawdata->dents[AAFS_LOADDATA_REVISION] = dent; + + if (aa_g_hash_policy) { + dent = aafs_create_file("sha1", S_IFREG | 0444, dir, + rawdata, &seq_rawdata_hash_fops); + if (IS_ERR(dent)) + goto fail; + rawdata->dents[AAFS_LOADDATA_HASH] = dent; + } + + dent = aafs_create_file("compressed_size", S_IFREG | 0444, dir, + rawdata, + &seq_rawdata_compressed_size_fops); + if (IS_ERR(dent)) + goto fail; + rawdata->dents[AAFS_LOADDATA_COMPRESSED_SIZE] = dent; + + dent = aafs_create_file("raw_data", S_IFREG | 0444, + dir, rawdata, &rawdata_fops); + if (IS_ERR(dent)) + goto fail; + rawdata->dents[AAFS_LOADDATA_DATA] = dent; + d_inode(dent)->i_size = rawdata->size; + + rawdata->ns = aa_get_ns(ns); + list_add(&rawdata->list, &ns->rawdata_list); + /* no refcount on inode rawdata */ + + return 0; + +fail: + remove_rawdata_dents(rawdata); + + return PTR_ERR(dent); +} +#endif /* CONFIG_SECURITY_APPARMOR_EXPORT_BINARY */ + + +/** fns to setup dynamic per profile/namespace files **/ + +/* + * + * Requires: @profile->ns->lock held + */ +void __aafs_profile_rmdir(struct aa_profile *profile) +{ + struct aa_profile *child; + int i; + + if (!profile) + return; + + list_for_each_entry(child, &profile->base.profiles, base.list) + __aafs_profile_rmdir(child); + + for (i = AAFS_PROF_SIZEOF - 1; i >= 0; --i) { + struct aa_proxy *proxy; + if (!profile->dents[i]) + continue; + + proxy = d_inode(profile->dents[i])->i_private; + aafs_remove(profile->dents[i]); + aa_put_proxy(proxy); + profile->dents[i] = NULL; + } +} + +/* + * + * Requires: @old->ns->lock held + */ +void __aafs_profile_migrate_dents(struct aa_profile *old, + struct aa_profile *new) +{ + int i; + + AA_BUG(!old); + AA_BUG(!new); + AA_BUG(!mutex_is_locked(&profiles_ns(old)->lock)); + + for (i = 0; i < AAFS_PROF_SIZEOF; i++) { + new->dents[i] = old->dents[i]; + if (new->dents[i]) { + struct inode *inode = d_inode(new->dents[i]); + + inode->i_mtime = inode_set_ctime_current(inode); + } + old->dents[i] = NULL; + } +} + +static struct dentry *create_profile_file(struct dentry *dir, const char *name, + struct aa_profile *profile, + const struct file_operations *fops) +{ + struct aa_proxy *proxy = aa_get_proxy(profile->label.proxy); + struct dentry *dent; + + dent = aafs_create_file(name, S_IFREG | 0444, dir, proxy, fops); + if (IS_ERR(dent)) + aa_put_proxy(proxy); + + return dent; +} + +#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY +static int profile_depth(struct aa_profile *profile) +{ + int depth = 0; + + rcu_read_lock(); + for (depth = 0; profile; profile = rcu_access_pointer(profile->parent)) + depth++; + rcu_read_unlock(); + + return depth; +} + +static char *gen_symlink_name(int depth, const char *dirname, const char *fname) +{ + char *buffer, *s; + int error; + int size = depth * 6 + strlen(dirname) + strlen(fname) + 11; + + s = buffer = kmalloc(size, GFP_KERNEL); + if (!buffer) + return ERR_PTR(-ENOMEM); + + for (; depth > 0; depth--) { + strcpy(s, "../../"); + s += 6; + size -= 6; + } + + error = snprintf(s, size, "raw_data/%s/%s", dirname, fname); + if (error >= size || error < 0) { + kfree(buffer); + return ERR_PTR(-ENAMETOOLONG); + } + + return buffer; +} + +static void rawdata_link_cb(void *arg) +{ + kfree(arg); +} + +static const char *rawdata_get_link_base(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done, + const char *name) +{ + struct aa_proxy *proxy = inode->i_private; + struct aa_label *label; + struct aa_profile *profile; + char *target; + int depth; + + if (!dentry) + return ERR_PTR(-ECHILD); + + label = aa_get_label_rcu(&proxy->label); + profile = labels_profile(label); + depth = profile_depth(profile); + target = gen_symlink_name(depth, profile->rawdata->name, name); + aa_put_label(label); + + if (IS_ERR(target)) + return target; + + set_delayed_call(done, rawdata_link_cb, target); + + return target; +} + +static const char *rawdata_get_link_sha1(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + return rawdata_get_link_base(dentry, inode, done, "sha1"); +} + +static const char *rawdata_get_link_abi(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + return rawdata_get_link_base(dentry, inode, done, "abi"); +} + +static const char *rawdata_get_link_data(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + return rawdata_get_link_base(dentry, inode, done, "raw_data"); +} + +static const struct inode_operations rawdata_link_sha1_iops = { + .get_link = rawdata_get_link_sha1, +}; + +static const struct inode_operations rawdata_link_abi_iops = { + .get_link = rawdata_get_link_abi, +}; +static const struct inode_operations rawdata_link_data_iops = { + .get_link = rawdata_get_link_data, +}; +#endif /* CONFIG_SECURITY_APPARMOR_EXPORT_BINARY */ + +/* + * Requires: @profile->ns->lock held + */ +int __aafs_profile_mkdir(struct aa_profile *profile, struct dentry *parent) +{ + struct aa_profile *child; + struct dentry *dent = NULL, *dir; + int error; + + AA_BUG(!profile); + AA_BUG(!mutex_is_locked(&profiles_ns(profile)->lock)); + + if (!parent) { + struct aa_profile *p; + p = aa_deref_parent(profile); + dent = prof_dir(p); + /* adding to parent that previously didn't have children */ + dent = aafs_create_dir("profiles", dent); + if (IS_ERR(dent)) + goto fail; + prof_child_dir(p) = parent = dent; + } + + if (!profile->dirname) { + int len, id_len; + len = mangle_name(profile->base.name, NULL); + id_len = snprintf(NULL, 0, ".%ld", profile->ns->uniq_id); + + profile->dirname = kmalloc(len + id_len + 1, GFP_KERNEL); + if (!profile->dirname) { + error = -ENOMEM; + goto fail2; + } + + mangle_name(profile->base.name, profile->dirname); + sprintf(profile->dirname + len, ".%ld", profile->ns->uniq_id++); + } + + dent = aafs_create_dir(profile->dirname, parent); + if (IS_ERR(dent)) + goto fail; + prof_dir(profile) = dir = dent; + + dent = create_profile_file(dir, "name", profile, + &seq_profile_name_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_NAME] = dent; + + dent = create_profile_file(dir, "mode", profile, + &seq_profile_mode_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_MODE] = dent; + + dent = create_profile_file(dir, "attach", profile, + &seq_profile_attach_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_ATTACH] = dent; + + if (profile->hash) { + dent = create_profile_file(dir, "sha1", profile, + &seq_profile_hash_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_HASH] = dent; + } + +#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY + if (profile->rawdata) { + if (aa_g_hash_policy) { + dent = aafs_create("raw_sha1", S_IFLNK | 0444, dir, + profile->label.proxy, NULL, NULL, + &rawdata_link_sha1_iops); + if (IS_ERR(dent)) + goto fail; + aa_get_proxy(profile->label.proxy); + profile->dents[AAFS_PROF_RAW_HASH] = dent; + } + dent = aafs_create("raw_abi", S_IFLNK | 0444, dir, + profile->label.proxy, NULL, NULL, + &rawdata_link_abi_iops); + if (IS_ERR(dent)) + goto fail; + aa_get_proxy(profile->label.proxy); + profile->dents[AAFS_PROF_RAW_ABI] = dent; + + dent = aafs_create("raw_data", S_IFLNK | 0444, dir, + profile->label.proxy, NULL, NULL, + &rawdata_link_data_iops); + if (IS_ERR(dent)) + goto fail; + aa_get_proxy(profile->label.proxy); + profile->dents[AAFS_PROF_RAW_DATA] = dent; + } +#endif /*CONFIG_SECURITY_APPARMOR_EXPORT_BINARY */ + + list_for_each_entry(child, &profile->base.profiles, base.list) { + error = __aafs_profile_mkdir(child, prof_child_dir(profile)); + if (error) + goto fail2; + } + + return 0; + +fail: + error = PTR_ERR(dent); + +fail2: + __aafs_profile_rmdir(profile); + + return error; +} + +static int ns_mkdir_op(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, umode_t mode) +{ + struct aa_ns *ns, *parent; + /* TODO: improve permission check */ + struct aa_label *label; + int error; + + label = begin_current_label_crit_section(); + error = aa_may_manage_policy(current_cred(), label, NULL, + AA_MAY_LOAD_POLICY); + end_current_label_crit_section(label); + if (error) + return error; + + parent = aa_get_ns(dir->i_private); + AA_BUG(d_inode(ns_subns_dir(parent)) != dir); + + /* we have to unlock and then relock to get locking order right + * for pin_fs + */ + inode_unlock(dir); + error = simple_pin_fs(&aafs_ops, &aafs_mnt, &aafs_count); + mutex_lock_nested(&parent->lock, parent->level); + inode_lock_nested(dir, I_MUTEX_PARENT); + if (error) + goto out; + + error = __aafs_setup_d_inode(dir, dentry, mode | S_IFDIR, NULL, + NULL, NULL, NULL); + if (error) + goto out_pin; + + ns = __aa_find_or_create_ns(parent, READ_ONCE(dentry->d_name.name), + dentry); + if (IS_ERR(ns)) { + error = PTR_ERR(ns); + ns = NULL; + } + + aa_put_ns(ns); /* list ref remains */ +out_pin: + if (error) + simple_release_fs(&aafs_mnt, &aafs_count); +out: + mutex_unlock(&parent->lock); + aa_put_ns(parent); + + return error; +} + +static int ns_rmdir_op(struct inode *dir, struct dentry *dentry) +{ + struct aa_ns *ns, *parent; + /* TODO: improve permission check */ + struct aa_label *label; + int error; + + label = begin_current_label_crit_section(); + error = aa_may_manage_policy(current_cred(), label, NULL, + AA_MAY_LOAD_POLICY); + end_current_label_crit_section(label); + if (error) + return error; + + parent = aa_get_ns(dir->i_private); + /* rmdir calls the generic securityfs functions to remove files + * from the apparmor dir. It is up to the apparmor ns locking + * to avoid races. + */ + inode_unlock(dir); + inode_unlock(dentry->d_inode); + + mutex_lock_nested(&parent->lock, parent->level); + ns = aa_get_ns(__aa_findn_ns(&parent->sub_ns, dentry->d_name.name, + dentry->d_name.len)); + if (!ns) { + error = -ENOENT; + goto out; + } + AA_BUG(ns_dir(ns) != dentry); + + __aa_remove_ns(ns); + aa_put_ns(ns); + +out: + mutex_unlock(&parent->lock); + inode_lock_nested(dir, I_MUTEX_PARENT); + inode_lock(dentry->d_inode); + aa_put_ns(parent); + + return error; +} + +static const struct inode_operations ns_dir_inode_operations = { + .lookup = simple_lookup, + .mkdir = ns_mkdir_op, + .rmdir = ns_rmdir_op, +}; + +static void __aa_fs_list_remove_rawdata(struct aa_ns *ns) +{ + struct aa_loaddata *ent, *tmp; + + AA_BUG(!mutex_is_locked(&ns->lock)); + + list_for_each_entry_safe(ent, tmp, &ns->rawdata_list, list) + __aa_fs_remove_rawdata(ent); +} + +/* + * + * Requires: @ns->lock held + */ +void __aafs_ns_rmdir(struct aa_ns *ns) +{ + struct aa_ns *sub; + struct aa_profile *child; + int i; + + if (!ns) + return; + AA_BUG(!mutex_is_locked(&ns->lock)); + + list_for_each_entry(child, &ns->base.profiles, base.list) + __aafs_profile_rmdir(child); + + list_for_each_entry(sub, &ns->sub_ns, base.list) { + mutex_lock_nested(&sub->lock, sub->level); + __aafs_ns_rmdir(sub); + mutex_unlock(&sub->lock); + } + + __aa_fs_list_remove_rawdata(ns); + + if (ns_subns_dir(ns)) { + sub = d_inode(ns_subns_dir(ns))->i_private; + aa_put_ns(sub); + } + if (ns_subload(ns)) { + sub = d_inode(ns_subload(ns))->i_private; + aa_put_ns(sub); + } + if (ns_subreplace(ns)) { + sub = d_inode(ns_subreplace(ns))->i_private; + aa_put_ns(sub); + } + if (ns_subremove(ns)) { + sub = d_inode(ns_subremove(ns))->i_private; + aa_put_ns(sub); + } + if (ns_subrevision(ns)) { + sub = d_inode(ns_subrevision(ns))->i_private; + aa_put_ns(sub); + } + + for (i = AAFS_NS_SIZEOF - 1; i >= 0; --i) { + aafs_remove(ns->dents[i]); + ns->dents[i] = NULL; + } +} + +/* assumes cleanup in caller */ +static int __aafs_ns_mkdir_entries(struct aa_ns *ns, struct dentry *dir) +{ + struct dentry *dent; + + AA_BUG(!ns); + AA_BUG(!dir); + + dent = aafs_create_dir("profiles", dir); + if (IS_ERR(dent)) + return PTR_ERR(dent); + ns_subprofs_dir(ns) = dent; + + dent = aafs_create_dir("raw_data", dir); + if (IS_ERR(dent)) + return PTR_ERR(dent); + ns_subdata_dir(ns) = dent; + + dent = aafs_create_file("revision", 0444, dir, ns, + &aa_fs_ns_revision_fops); + if (IS_ERR(dent)) + return PTR_ERR(dent); + aa_get_ns(ns); + ns_subrevision(ns) = dent; + + dent = aafs_create_file(".load", 0640, dir, ns, + &aa_fs_profile_load); + if (IS_ERR(dent)) + return PTR_ERR(dent); + aa_get_ns(ns); + ns_subload(ns) = dent; + + dent = aafs_create_file(".replace", 0640, dir, ns, + &aa_fs_profile_replace); + if (IS_ERR(dent)) + return PTR_ERR(dent); + aa_get_ns(ns); + ns_subreplace(ns) = dent; + + dent = aafs_create_file(".remove", 0640, dir, ns, + &aa_fs_profile_remove); + if (IS_ERR(dent)) + return PTR_ERR(dent); + aa_get_ns(ns); + ns_subremove(ns) = dent; + + /* use create_dentry so we can supply private data */ + dent = aafs_create("namespaces", S_IFDIR | 0755, dir, ns, NULL, NULL, + &ns_dir_inode_operations); + if (IS_ERR(dent)) + return PTR_ERR(dent); + aa_get_ns(ns); + ns_subns_dir(ns) = dent; + + return 0; +} + +/* + * Requires: @ns->lock held + */ +int __aafs_ns_mkdir(struct aa_ns *ns, struct dentry *parent, const char *name, + struct dentry *dent) +{ + struct aa_ns *sub; + struct aa_profile *child; + struct dentry *dir; + int error; + + AA_BUG(!ns); + AA_BUG(!parent); + AA_BUG(!mutex_is_locked(&ns->lock)); + + if (!name) + name = ns->base.name; + + if (!dent) { + /* create ns dir if it doesn't already exist */ + dent = aafs_create_dir(name, parent); + if (IS_ERR(dent)) + goto fail; + } else + dget(dent); + ns_dir(ns) = dir = dent; + error = __aafs_ns_mkdir_entries(ns, dir); + if (error) + goto fail2; + + /* profiles */ + list_for_each_entry(child, &ns->base.profiles, base.list) { + error = __aafs_profile_mkdir(child, ns_subprofs_dir(ns)); + if (error) + goto fail2; + } + + /* subnamespaces */ + list_for_each_entry(sub, &ns->sub_ns, base.list) { + mutex_lock_nested(&sub->lock, sub->level); + error = __aafs_ns_mkdir(sub, ns_subns_dir(ns), NULL, NULL); + mutex_unlock(&sub->lock); + if (error) + goto fail2; + } + + return 0; + +fail: + error = PTR_ERR(dent); + +fail2: + __aafs_ns_rmdir(ns); + + return error; +} + +/** + * __next_ns - find the next namespace to list + * @root: root namespace to stop search at (NOT NULL) + * @ns: current ns position (NOT NULL) + * + * Find the next namespace from @ns under @root and handle all locking needed + * while switching current namespace. + * + * Returns: next namespace or NULL if at last namespace under @root + * Requires: ns->parent->lock to be held + * NOTE: will not unlock root->lock + */ +static struct aa_ns *__next_ns(struct aa_ns *root, struct aa_ns *ns) +{ + struct aa_ns *parent, *next; + + AA_BUG(!root); + AA_BUG(!ns); + AA_BUG(ns != root && !mutex_is_locked(&ns->parent->lock)); + + /* is next namespace a child */ + if (!list_empty(&ns->sub_ns)) { + next = list_first_entry(&ns->sub_ns, typeof(*ns), base.list); + mutex_lock_nested(&next->lock, next->level); + return next; + } + + /* check if the next ns is a sibling, parent, gp, .. */ + parent = ns->parent; + while (ns != root) { + mutex_unlock(&ns->lock); + next = list_next_entry(ns, base.list); + if (!list_entry_is_head(next, &parent->sub_ns, base.list)) { + mutex_lock_nested(&next->lock, next->level); + return next; + } + ns = parent; + parent = parent->parent; + } + + return NULL; +} + +/** + * __first_profile - find the first profile in a namespace + * @root: namespace that is root of profiles being displayed (NOT NULL) + * @ns: namespace to start in (NOT NULL) + * + * Returns: unrefcounted profile or NULL if no profile + * Requires: profile->ns.lock to be held + */ +static struct aa_profile *__first_profile(struct aa_ns *root, + struct aa_ns *ns) +{ + AA_BUG(!root); + AA_BUG(ns && !mutex_is_locked(&ns->lock)); + + for (; ns; ns = __next_ns(root, ns)) { + if (!list_empty(&ns->base.profiles)) + return list_first_entry(&ns->base.profiles, + struct aa_profile, base.list); + } + return NULL; +} + +/** + * __next_profile - step to the next profile in a profile tree + * @p: current profile in tree (NOT NULL) + * + * Perform a depth first traversal on the profile tree in a namespace + * + * Returns: next profile or NULL if done + * Requires: profile->ns.lock to be held + */ +static struct aa_profile *__next_profile(struct aa_profile *p) +{ + struct aa_profile *parent; + struct aa_ns *ns = p->ns; + + AA_BUG(!mutex_is_locked(&profiles_ns(p)->lock)); + + /* is next profile a child */ + if (!list_empty(&p->base.profiles)) + return list_first_entry(&p->base.profiles, typeof(*p), + base.list); + + /* is next profile a sibling, parent sibling, gp, sibling, .. */ + parent = rcu_dereference_protected(p->parent, + mutex_is_locked(&p->ns->lock)); + while (parent) { + p = list_next_entry(p, base.list); + if (!list_entry_is_head(p, &parent->base.profiles, base.list)) + return p; + p = parent; + parent = rcu_dereference_protected(parent->parent, + mutex_is_locked(&parent->ns->lock)); + } + + /* is next another profile in the namespace */ + p = list_next_entry(p, base.list); + if (!list_entry_is_head(p, &ns->base.profiles, base.list)) + return p; + + return NULL; +} + +/** + * next_profile - step to the next profile in where ever it may be + * @root: root namespace (NOT NULL) + * @profile: current profile (NOT NULL) + * + * Returns: next profile or NULL if there isn't one + */ +static struct aa_profile *next_profile(struct aa_ns *root, + struct aa_profile *profile) +{ + struct aa_profile *next = __next_profile(profile); + if (next) + return next; + + /* finished all profiles in namespace move to next namespace */ + return __first_profile(root, __next_ns(root, profile->ns)); +} + +/** + * p_start - start a depth first traversal of profile tree + * @f: seq_file to fill + * @pos: current position + * + * Returns: first profile under current namespace or NULL if none found + * + * acquires first ns->lock + */ +static void *p_start(struct seq_file *f, loff_t *pos) +{ + struct aa_profile *profile = NULL; + struct aa_ns *root = aa_get_current_ns(); + loff_t l = *pos; + f->private = root; + + /* find the first profile */ + mutex_lock_nested(&root->lock, root->level); + profile = __first_profile(root, root); + + /* skip to position */ + for (; profile && l > 0; l--) + profile = next_profile(root, profile); + + return profile; +} + +/** + * p_next - read the next profile entry + * @f: seq_file to fill + * @p: profile previously returned + * @pos: current position + * + * Returns: next profile after @p or NULL if none + * + * may acquire/release locks in namespace tree as necessary + */ +static void *p_next(struct seq_file *f, void *p, loff_t *pos) +{ + struct aa_profile *profile = p; + struct aa_ns *ns = f->private; + (*pos)++; + + return next_profile(ns, profile); +} + +/** + * p_stop - stop depth first traversal + * @f: seq_file we are filling + * @p: the last profile writen + * + * Release all locking done by p_start/p_next on namespace tree + */ +static void p_stop(struct seq_file *f, void *p) +{ + struct aa_profile *profile = p; + struct aa_ns *root = f->private, *ns; + + if (profile) { + for (ns = profile->ns; ns && ns != root; ns = ns->parent) + mutex_unlock(&ns->lock); + } + mutex_unlock(&root->lock); + aa_put_ns(root); +} + +/** + * seq_show_profile - show a profile entry + * @f: seq_file to file + * @p: current position (profile) (NOT NULL) + * + * Returns: error on failure + */ +static int seq_show_profile(struct seq_file *f, void *p) +{ + struct aa_profile *profile = (struct aa_profile *)p; + struct aa_ns *root = f->private; + + aa_label_seq_xprint(f, root, &profile->label, + FLAG_SHOW_MODE | FLAG_VIEW_SUBNS, GFP_KERNEL); + seq_putc(f, '\n'); + + return 0; +} + +static const struct seq_operations aa_sfs_profiles_op = { + .start = p_start, + .next = p_next, + .stop = p_stop, + .show = seq_show_profile, +}; + +static int profiles_open(struct inode *inode, struct file *file) +{ + if (!aa_current_policy_view_capable(NULL)) + return -EACCES; + + return seq_open(file, &aa_sfs_profiles_op); +} + +static int profiles_release(struct inode *inode, struct file *file) +{ + return seq_release(inode, file); +} + +static const struct file_operations aa_sfs_profiles_fops = { + .open = profiles_open, + .read = seq_read, + .llseek = seq_lseek, + .release = profiles_release, +}; + + +/** Base file system setup **/ +static struct aa_sfs_entry aa_sfs_entry_file[] = { + AA_SFS_FILE_STRING("mask", + "create read write exec append mmap_exec link lock"), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_ptrace[] = { + AA_SFS_FILE_STRING("mask", "read trace"), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_signal[] = { + AA_SFS_FILE_STRING("mask", AA_SFS_SIG_MASK), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_attach[] = { + AA_SFS_FILE_BOOLEAN("xattr", 1), + { } +}; +static struct aa_sfs_entry aa_sfs_entry_domain[] = { + AA_SFS_FILE_BOOLEAN("change_hat", 1), + AA_SFS_FILE_BOOLEAN("change_hatv", 1), + AA_SFS_FILE_BOOLEAN("change_onexec", 1), + AA_SFS_FILE_BOOLEAN("change_profile", 1), + AA_SFS_FILE_BOOLEAN("stack", 1), + AA_SFS_FILE_BOOLEAN("fix_binfmt_elf_mmap", 1), + AA_SFS_FILE_BOOLEAN("post_nnp_subset", 1), + AA_SFS_FILE_BOOLEAN("computed_longest_left", 1), + AA_SFS_DIR("attach_conditions", aa_sfs_entry_attach), + AA_SFS_FILE_STRING("version", "1.2"), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_versions[] = { + AA_SFS_FILE_BOOLEAN("v5", 1), + AA_SFS_FILE_BOOLEAN("v6", 1), + AA_SFS_FILE_BOOLEAN("v7", 1), + AA_SFS_FILE_BOOLEAN("v8", 1), + AA_SFS_FILE_BOOLEAN("v9", 1), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_policy[] = { + AA_SFS_DIR("versions", aa_sfs_entry_versions), + AA_SFS_FILE_BOOLEAN("set_load", 1), + /* number of out of band transitions supported */ + AA_SFS_FILE_U64("outofband", MAX_OOB_SUPPORTED), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_mount[] = { + AA_SFS_FILE_STRING("mask", "mount umount pivot_root"), + AA_SFS_FILE_STRING("move_mount", "detached"), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_ns[] = { + AA_SFS_FILE_BOOLEAN("profile", 1), + AA_SFS_FILE_BOOLEAN("pivot_root", 0), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_query_label[] = { + AA_SFS_FILE_STRING("perms", "allow deny audit quiet"), + AA_SFS_FILE_BOOLEAN("data", 1), + AA_SFS_FILE_BOOLEAN("multi_transaction", 1), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_query[] = { + AA_SFS_DIR("label", aa_sfs_entry_query_label), + { } +}; +static struct aa_sfs_entry aa_sfs_entry_features[] = { + AA_SFS_DIR("policy", aa_sfs_entry_policy), + AA_SFS_DIR("domain", aa_sfs_entry_domain), + AA_SFS_DIR("file", aa_sfs_entry_file), + AA_SFS_DIR("network_v8", aa_sfs_entry_network), + AA_SFS_DIR("mount", aa_sfs_entry_mount), + AA_SFS_DIR("namespaces", aa_sfs_entry_ns), + AA_SFS_FILE_U64("capability", VFS_CAP_FLAGS_MASK), + AA_SFS_DIR("rlimit", aa_sfs_entry_rlimit), + AA_SFS_DIR("caps", aa_sfs_entry_caps), + AA_SFS_DIR("ptrace", aa_sfs_entry_ptrace), + AA_SFS_DIR("signal", aa_sfs_entry_signal), + AA_SFS_DIR("query", aa_sfs_entry_query), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry_apparmor[] = { + AA_SFS_FILE_FOPS(".access", 0666, &aa_sfs_access), + AA_SFS_FILE_FOPS(".stacked", 0444, &seq_ns_stacked_fops), + AA_SFS_FILE_FOPS(".ns_stacked", 0444, &seq_ns_nsstacked_fops), + AA_SFS_FILE_FOPS(".ns_level", 0444, &seq_ns_level_fops), + AA_SFS_FILE_FOPS(".ns_name", 0444, &seq_ns_name_fops), + AA_SFS_FILE_FOPS("profiles", 0444, &aa_sfs_profiles_fops), + AA_SFS_FILE_FOPS("raw_data_compression_level_min", 0444, &seq_ns_compress_min_fops), + AA_SFS_FILE_FOPS("raw_data_compression_level_max", 0444, &seq_ns_compress_max_fops), + AA_SFS_DIR("features", aa_sfs_entry_features), + { } +}; + +static struct aa_sfs_entry aa_sfs_entry = + AA_SFS_DIR("apparmor", aa_sfs_entry_apparmor); + +/** + * entry_create_file - create a file entry in the apparmor securityfs + * @fs_file: aa_sfs_entry to build an entry for (NOT NULL) + * @parent: the parent dentry in the securityfs + * + * Use entry_remove_file to remove entries created with this fn. + */ +static int __init entry_create_file(struct aa_sfs_entry *fs_file, + struct dentry *parent) +{ + int error = 0; + + fs_file->dentry = securityfs_create_file(fs_file->name, + S_IFREG | fs_file->mode, + parent, fs_file, + fs_file->file_ops); + if (IS_ERR(fs_file->dentry)) { + error = PTR_ERR(fs_file->dentry); + fs_file->dentry = NULL; + } + return error; +} + +static void __init entry_remove_dir(struct aa_sfs_entry *fs_dir); +/** + * entry_create_dir - recursively create a directory entry in the securityfs + * @fs_dir: aa_sfs_entry (and all child entries) to build (NOT NULL) + * @parent: the parent dentry in the securityfs + * + * Use entry_remove_dir to remove entries created with this fn. + */ +static int __init entry_create_dir(struct aa_sfs_entry *fs_dir, + struct dentry *parent) +{ + struct aa_sfs_entry *fs_file; + struct dentry *dir; + int error; + + dir = securityfs_create_dir(fs_dir->name, parent); + if (IS_ERR(dir)) + return PTR_ERR(dir); + fs_dir->dentry = dir; + + for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) { + if (fs_file->v_type == AA_SFS_TYPE_DIR) + error = entry_create_dir(fs_file, fs_dir->dentry); + else + error = entry_create_file(fs_file, fs_dir->dentry); + if (error) + goto failed; + } + + return 0; + +failed: + entry_remove_dir(fs_dir); + + return error; +} + +/** + * entry_remove_file - drop a single file entry in the apparmor securityfs + * @fs_file: aa_sfs_entry to detach from the securityfs (NOT NULL) + */ +static void __init entry_remove_file(struct aa_sfs_entry *fs_file) +{ + if (!fs_file->dentry) + return; + + securityfs_remove(fs_file->dentry); + fs_file->dentry = NULL; +} + +/** + * entry_remove_dir - recursively drop a directory entry from the securityfs + * @fs_dir: aa_sfs_entry (and all child entries) to detach (NOT NULL) + */ +static void __init entry_remove_dir(struct aa_sfs_entry *fs_dir) +{ + struct aa_sfs_entry *fs_file; + + for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) { + if (fs_file->v_type == AA_SFS_TYPE_DIR) + entry_remove_dir(fs_file); + else + entry_remove_file(fs_file); + } + + entry_remove_file(fs_dir); +} + +/** + * aa_destroy_aafs - cleanup and free aafs + * + * releases dentries allocated by aa_create_aafs + */ +void __init aa_destroy_aafs(void) +{ + entry_remove_dir(&aa_sfs_entry); +} + + +#define NULL_FILE_NAME ".null" +struct path aa_null; + +static int aa_mk_null_file(struct dentry *parent) +{ + struct vfsmount *mount = NULL; + struct dentry *dentry; + struct inode *inode; + int count = 0; + int error = simple_pin_fs(parent->d_sb->s_type, &mount, &count); + + if (error) + return error; + + inode_lock(d_inode(parent)); + dentry = lookup_one_len(NULL_FILE_NAME, parent, strlen(NULL_FILE_NAME)); + if (IS_ERR(dentry)) { + error = PTR_ERR(dentry); + goto out; + } + inode = new_inode(parent->d_inode->i_sb); + if (!inode) { + error = -ENOMEM; + goto out1; + } + + inode->i_ino = get_next_ino(); + inode->i_mode = S_IFCHR | S_IRUGO | S_IWUGO; + inode->i_atime = inode->i_mtime = inode_set_ctime_current(inode); + init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, + MKDEV(MEM_MAJOR, 3)); + d_instantiate(dentry, inode); + aa_null.dentry = dget(dentry); + aa_null.mnt = mntget(mount); + + error = 0; + +out1: + dput(dentry); +out: + inode_unlock(d_inode(parent)); + simple_release_fs(&mount, &count); + return error; +} + + + +static const char *policy_get_link(struct dentry *dentry, + struct inode *inode, + struct delayed_call *done) +{ + struct aa_ns *ns; + struct path path; + int error; + + if (!dentry) + return ERR_PTR(-ECHILD); + + ns = aa_get_current_ns(); + path.mnt = mntget(aafs_mnt); + path.dentry = dget(ns_dir(ns)); + error = nd_jump_link(&path); + aa_put_ns(ns); + + return ERR_PTR(error); +} + +static int policy_readlink(struct dentry *dentry, char __user *buffer, + int buflen) +{ + char name[32]; + int res; + + res = snprintf(name, sizeof(name), "%s:[%lu]", AAFS_NAME, + d_inode(dentry)->i_ino); + if (res > 0 && res < sizeof(name)) + res = readlink_copy(buffer, buflen, name); + else + res = -ENOENT; + + return res; +} + +static const struct inode_operations policy_link_iops = { + .readlink = policy_readlink, + .get_link = policy_get_link, +}; + + +/** + * aa_create_aafs - create the apparmor security filesystem + * + * dentries created here are released by aa_destroy_aafs + * + * Returns: error on failure + */ +static int __init aa_create_aafs(void) +{ + struct dentry *dent; + int error; + + if (!apparmor_initialized) + return 0; + + if (aa_sfs_entry.dentry) { + AA_ERROR("%s: AppArmor securityfs already exists\n", __func__); + return -EEXIST; + } + + /* setup apparmorfs used to virtualize policy/ */ + aafs_mnt = kern_mount(&aafs_ops); + if (IS_ERR(aafs_mnt)) + panic("can't set apparmorfs up\n"); + aafs_mnt->mnt_sb->s_flags &= ~SB_NOUSER; + + /* Populate fs tree. */ + error = entry_create_dir(&aa_sfs_entry, NULL); + if (error) + goto error; + + dent = securityfs_create_file(".load", 0666, aa_sfs_entry.dentry, + NULL, &aa_fs_profile_load); + if (IS_ERR(dent)) + goto dent_error; + ns_subload(root_ns) = dent; + + dent = securityfs_create_file(".replace", 0666, aa_sfs_entry.dentry, + NULL, &aa_fs_profile_replace); + if (IS_ERR(dent)) + goto dent_error; + ns_subreplace(root_ns) = dent; + + dent = securityfs_create_file(".remove", 0666, aa_sfs_entry.dentry, + NULL, &aa_fs_profile_remove); + if (IS_ERR(dent)) + goto dent_error; + ns_subremove(root_ns) = dent; + + dent = securityfs_create_file("revision", 0444, aa_sfs_entry.dentry, + NULL, &aa_fs_ns_revision_fops); + if (IS_ERR(dent)) + goto dent_error; + ns_subrevision(root_ns) = dent; + + /* policy tree referenced by magic policy symlink */ + mutex_lock_nested(&root_ns->lock, root_ns->level); + error = __aafs_ns_mkdir(root_ns, aafs_mnt->mnt_root, ".policy", + aafs_mnt->mnt_root); + mutex_unlock(&root_ns->lock); + if (error) + goto error; + + /* magic symlink similar to nsfs redirects based on task policy */ + dent = securityfs_create_symlink("policy", aa_sfs_entry.dentry, + NULL, &policy_link_iops); + if (IS_ERR(dent)) + goto dent_error; + + error = aa_mk_null_file(aa_sfs_entry.dentry); + if (error) + goto error; + + /* TODO: add default profile to apparmorfs */ + + /* Report that AppArmor fs is enabled */ + aa_info_message("AppArmor Filesystem Enabled"); + return 0; + +dent_error: + error = PTR_ERR(dent); +error: + aa_destroy_aafs(); + AA_ERROR("Error creating AppArmor securityfs\n"); + return error; +} + +fs_initcall(aa_create_aafs); |