From 9acd494be9387b0608612cd139967201dd7a4e12 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 26 Jan 2012 16:29:20 -0800 Subject: AppArmor: refactor securityfs to use structures Use a file tree structure to represent the AppArmor securityfs. Signed-off-by: Kees Cook Signed-off-by: John Johansen --- security/apparmor/apparmorfs.c | 132 ++++++++++++++++++++++----------- security/apparmor/include/apparmorfs.h | 24 ++++++ 2 files changed, 114 insertions(+), 42 deletions(-) (limited to 'security') diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index e39df6d43779..1e22bb3a8851 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -144,36 +144,103 @@ static const struct file_operations aa_fs_profile_remove = { /** Base file system setup **/ -static struct dentry *aa_fs_dentry __initdata; +static struct aa_fs_entry aa_fs_entry_apparmor[] = { + AA_FS_FILE_FOPS(".load", 0640, &aa_fs_profile_load), + AA_FS_FILE_FOPS(".replace", 0640, &aa_fs_profile_replace), + AA_FS_FILE_FOPS(".remove", 0640, &aa_fs_profile_remove), + { } +}; -static void __init aafs_remove(const char *name) -{ - struct dentry *dentry; +static struct aa_fs_entry aa_fs_entry = + AA_FS_DIR("apparmor", aa_fs_entry_apparmor); - dentry = lookup_one_len(name, aa_fs_dentry, strlen(name)); - if (!IS_ERR(dentry)) { - securityfs_remove(dentry); - dput(dentry); +/** + * aafs_create_file - create a file entry in the apparmor securityfs + * @fs_file: aa_fs_entry to build an entry for (NOT NULL) + * @parent: the parent dentry in the securityfs + * + * Use aafs_remove_file to remove entries created with this fn. + */ +static int __init aafs_create_file(struct aa_fs_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; } /** - * aafs_create - create an entry in the apparmor filesystem - * @name: name of the entry (NOT NULL) - * @mask: file permission mask of the file - * @fops: file operations for the file (NOT NULL) + * aafs_create_dir - recursively create a directory entry in the securityfs + * @fs_dir: aa_fs_entry (and all child entries) to build (NOT NULL) + * @parent: the parent dentry in the securityfs * - * Used aafs_remove to remove entries created with this fn. + * Use aafs_remove_dir to remove entries created with this fn. */ -static int __init aafs_create(const char *name, umode_t mask, - const struct file_operations *fops) +static int __init aafs_create_dir(struct aa_fs_entry *fs_dir, + struct dentry *parent) { - struct dentry *dentry; + int error; + struct aa_fs_entry *fs_file; - dentry = securityfs_create_file(name, S_IFREG | mask, aa_fs_dentry, - NULL, fops); + fs_dir->dentry = securityfs_create_dir(fs_dir->name, parent); + if (IS_ERR(fs_dir->dentry)) { + error = PTR_ERR(fs_dir->dentry); + fs_dir->dentry = NULL; + goto failed; + } - return IS_ERR(dentry) ? PTR_ERR(dentry) : 0; + for (fs_file = fs_dir->v.files; fs_file->name; ++fs_file) { + if (fs_file->v_type == AA_FS_TYPE_DIR) + error = aafs_create_dir(fs_file, fs_dir->dentry); + else + error = aafs_create_file(fs_file, fs_dir->dentry); + if (error) + goto failed; + } + + return 0; + +failed: + return error; +} + +/** + * aafs_remove_file - drop a single file entry in the apparmor securityfs + * @fs_file: aa_fs_entry to detach from the securityfs (NOT NULL) + */ +static void __init aafs_remove_file(struct aa_fs_entry *fs_file) +{ + if (!fs_file->dentry) + return; + + securityfs_remove(fs_file->dentry); + fs_file->dentry = NULL; +} + +/** + * aafs_remove_dir - recursively drop a directory entry from the securityfs + * @fs_dir: aa_fs_entry (and all child entries) to detach (NOT NULL) + */ +static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir) +{ + struct aa_fs_entry *fs_file; + + for (fs_file = fs_dir->v.files; fs_file->name; ++fs_file) { + if (fs_file->v_type == AA_FS_TYPE_DIR) + aafs_remove_dir(fs_file); + else + aafs_remove_file(fs_file); + } + + aafs_remove_file(fs_dir); } /** @@ -183,14 +250,7 @@ static int __init aafs_create(const char *name, umode_t mask, */ void __init aa_destroy_aafs(void) { - if (aa_fs_dentry) { - aafs_remove(".remove"); - aafs_remove(".replace"); - aafs_remove(".load"); - - securityfs_remove(aa_fs_dentry); - aa_fs_dentry = NULL; - } + aafs_remove_dir(&aa_fs_entry); } /** @@ -207,25 +267,13 @@ static int __init aa_create_aafs(void) if (!apparmor_initialized) return 0; - if (aa_fs_dentry) { + if (aa_fs_entry.dentry) { AA_ERROR("%s: AppArmor securityfs already exists\n", __func__); return -EEXIST; } - aa_fs_dentry = securityfs_create_dir("apparmor", NULL); - if (IS_ERR(aa_fs_dentry)) { - error = PTR_ERR(aa_fs_dentry); - aa_fs_dentry = NULL; - goto error; - } - - error = aafs_create(".load", 0640, &aa_fs_profile_load); - if (error) - goto error; - error = aafs_create(".replace", 0640, &aa_fs_profile_replace); - if (error) - goto error; - error = aafs_create(".remove", 0640, &aa_fs_profile_remove); + /* Populate fs tree. */ + error = aafs_create_dir(&aa_fs_entry, NULL); if (error) goto error; diff --git a/security/apparmor/include/apparmorfs.h b/security/apparmor/include/apparmorfs.h index cb1e93a114d7..4fdf02f26a3a 100644 --- a/security/apparmor/include/apparmorfs.h +++ b/security/apparmor/include/apparmorfs.h @@ -15,6 +15,30 @@ #ifndef __AA_APPARMORFS_H #define __AA_APPARMORFS_H +enum aa_fs_type { + AA_FS_TYPE_FOPS, + AA_FS_TYPE_DIR, +}; + +struct aa_fs_entry; + +struct aa_fs_entry { + const char *name; + struct dentry *dentry; + umode_t mode; + enum aa_fs_type v_type; + union { + struct aa_fs_entry *files; + } v; + const struct file_operations *file_ops; +}; + +#define AA_FS_FILE_FOPS(_name, _mode, _fops) \ + { .name = (_name), .v_type = AA_FS_TYPE_FOPS, \ + .mode = (_mode), .file_ops = (_fops) } +#define AA_FS_DIR(_name, _value) \ + { .name = (_name), .v_type = AA_FS_TYPE_DIR, .v.files = (_value) } + extern void __init aa_destroy_aafs(void); #endif /* __AA_APPARMORFS_H */ -- cgit v1.2.3-59-g8ed1b