From b5e95b48685e3481139a5634d14d630d12c7d5ce Mon Sep 17 00:00:00 2001 From: John Johansen Date: Thu, 29 Jul 2010 14:48:07 -0700 Subject: [PATCH] AppArmor: LSM interface, and security module initialization AppArmor hooks to interface with the LSM, module parameters and module initialization. Signed-off-by: John Johansen Signed-off-by: James Morris --- security/apparmor/lsm.c | 939 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 939 insertions(+) create mode 100644 security/apparmor/lsm.c diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c new file mode 100644 index 000000000000..7daf0d528037 --- /dev/null +++ b/security/apparmor/lsm.c @@ -0,0 +1,939 @@ +/* + * AppArmor security module + * + * This file contains AppArmor LSM hooks. + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "include/apparmor.h" +#include "include/apparmorfs.h" +#include "include/audit.h" +#include "include/capability.h" +#include "include/context.h" +#include "include/file.h" +#include "include/ipc.h" +#include "include/path.h" +#include "include/policy.h" +#include "include/procattr.h" + +/* Flag indicating whether initialization completed */ +int apparmor_initialized __initdata; + +/* + * LSM hook functions + */ + +/* + * free the associated aa_task_cxt and put its profiles + */ +static void apparmor_cred_free(struct cred *cred) +{ + aa_free_task_context(cred->security); + cred->security = NULL; +} + +/* + * allocate the apparmor part of blank credentials + */ +static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp) +{ + /* freed by apparmor_cred_free */ + struct aa_task_cxt *cxt = aa_alloc_task_context(gfp); + if (!cxt) + return -ENOMEM; + + cred->security = cxt; + return 0; +} + +/* + * prepare new aa_task_cxt for modification by prepare_cred block + */ +static int apparmor_cred_prepare(struct cred *new, const struct cred *old, + gfp_t gfp) +{ + /* freed by apparmor_cred_free */ + struct aa_task_cxt *cxt = aa_alloc_task_context(gfp); + if (!cxt) + return -ENOMEM; + + aa_dup_task_context(cxt, old->security); + new->security = cxt; + return 0; +} + +/* + * transfer the apparmor data to a blank set of creds + */ +static void apparmor_cred_transfer(struct cred *new, const struct cred *old) +{ + const struct aa_task_cxt *old_cxt = old->security; + struct aa_task_cxt *new_cxt = new->security; + + aa_dup_task_context(new_cxt, old_cxt); +} + +static int apparmor_ptrace_access_check(struct task_struct *child, + unsigned int mode) +{ + int error = cap_ptrace_access_check(child, mode); + if (error) + return error; + + return aa_ptrace(current, child, mode); +} + +static int apparmor_ptrace_traceme(struct task_struct *parent) +{ + int error = cap_ptrace_traceme(parent); + if (error) + return error; + + return aa_ptrace(parent, current, PTRACE_MODE_ATTACH); +} + +/* Derived from security/commoncap.c:cap_capget */ +static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective, + kernel_cap_t *inheritable, kernel_cap_t *permitted) +{ + struct aa_profile *profile; + const struct cred *cred; + + rcu_read_lock(); + cred = __task_cred(target); + profile = aa_cred_profile(cred); + + *effective = cred->cap_effective; + *inheritable = cred->cap_inheritable; + *permitted = cred->cap_permitted; + + if (!unconfined(profile)) { + *effective = cap_intersect(*effective, profile->caps.allow); + *permitted = cap_intersect(*permitted, profile->caps.allow); + } + rcu_read_unlock(); + + return 0; +} + +static int apparmor_capable(struct task_struct *task, const struct cred *cred, + int cap, int audit) +{ + struct aa_profile *profile; + /* cap_capable returns 0 on success, else -EPERM */ + int error = cap_capable(task, cred, cap, audit); + if (!error) { + profile = aa_cred_profile(cred); + if (!unconfined(profile)) + error = aa_capable(task, profile, cap, audit); + } + return error; +} + +/** + * common_perm - basic common permission check wrapper fn for paths + * @op: operation being checked + * @path: path to check permission of (NOT NULL) + * @mask: requested permissions mask + * @cond: conditional info for the permission request (NOT NULL) + * + * Returns: %0 else error code if error or permission denied + */ +static int common_perm(int op, struct path *path, u32 mask, + struct path_cond *cond) +{ + struct aa_profile *profile; + int error = 0; + + profile = __aa_current_profile(); + if (!unconfined(profile)) + error = aa_path_perm(op, profile, path, 0, mask, cond); + + return error; +} + +/** + * common_perm_dir_dentry - common permission wrapper when path is dir, dentry + * @op: operation being checked + * @dir: directory of the dentry (NOT NULL) + * @dentry: dentry to check (NOT NULL) + * @mask: requested permissions mask + * @cond: conditional info for the permission request (NOT NULL) + * + * Returns: %0 else error code if error or permission denied + */ +static int common_perm_dir_dentry(int op, struct path *dir, + struct dentry *dentry, u32 mask, + struct path_cond *cond) +{ + struct path path = { dir->mnt, dentry }; + + return common_perm(op, &path, mask, cond); +} + +/** + * common_perm_mnt_dentry - common permission wrapper when mnt, dentry + * @op: operation being checked + * @mnt: mount point of dentry (NOT NULL) + * @dentry: dentry to check (NOT NULL) + * @mask: requested permissions mask + * + * Returns: %0 else error code if error or permission denied + */ +static int common_perm_mnt_dentry(int op, struct vfsmount *mnt, + struct dentry *dentry, u32 mask) +{ + struct path path = { mnt, dentry }; + struct path_cond cond = { dentry->d_inode->i_uid, + dentry->d_inode->i_mode + }; + + return common_perm(op, &path, mask, &cond); +} + +/** + * common_perm_rm - common permission wrapper for operations doing rm + * @op: operation being checked + * @dir: directory that the dentry is in (NOT NULL) + * @dentry: dentry being rm'd (NOT NULL) + * @mask: requested permission mask + * + * Returns: %0 else error code if error or permission denied + */ +static int common_perm_rm(int op, struct path *dir, + struct dentry *dentry, u32 mask) +{ + struct inode *inode = dentry->d_inode; + struct path_cond cond = { }; + + if (!inode || !dir->mnt || !mediated_filesystem(inode)) + return 0; + + cond.uid = inode->i_uid; + cond.mode = inode->i_mode; + + return common_perm_dir_dentry(op, dir, dentry, mask, &cond); +} + +/** + * common_perm_create - common permission wrapper for operations doing create + * @op: operation being checked + * @dir: directory that dentry will be created in (NOT NULL) + * @dentry: dentry to create (NOT NULL) + * @mask: request permission mask + * @mode: created file mode + * + * Returns: %0 else error code if error or permission denied + */ +static int common_perm_create(int op, struct path *dir, struct dentry *dentry, + u32 mask, umode_t mode) +{ + struct path_cond cond = { current_fsuid(), mode }; + + if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode)) + return 0; + + return common_perm_dir_dentry(op, dir, dentry, mask, &cond); +} + +static int apparmor_path_unlink(struct path *dir, struct dentry *dentry) +{ + return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE); +} + +static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry, + int mode) +{ + return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE, + S_IFDIR); +} + +static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry) +{ + return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE); +} + +static int apparmor_path_mknod(struct path *dir, struct dentry *dentry, + int mode, unsigned int dev) +{ + return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode); +} + +static int apparmor_path_truncate(struct path *path, loff_t length, + unsigned int time_attrs) +{ + struct path_cond cond = { path->dentry->d_inode->i_uid, + path->dentry->d_inode->i_mode + }; + + if (!path->mnt || !mediated_filesystem(path->dentry->d_inode)) + return 0; + + return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE, + &cond); +} + +static int apparmor_path_symlink(struct path *dir, struct dentry *dentry, + const char *old_name) +{ + return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE, + S_IFLNK); +} + +static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir, + struct dentry *new_dentry) +{ + struct aa_profile *profile; + int error = 0; + + if (!mediated_filesystem(old_dentry->d_inode)) + return 0; + + profile = aa_current_profile(); + if (!unconfined(profile)) + error = aa_path_link(profile, old_dentry, new_dir, new_dentry); + return error; +} + +static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry, + struct path *new_dir, struct dentry *new_dentry) +{ + struct aa_profile *profile; + int error = 0; + + if (!mediated_filesystem(old_dentry->d_inode)) + return 0; + + profile = aa_current_profile(); + if (!unconfined(profile)) { + struct path old_path = { old_dir->mnt, old_dentry }; + struct path new_path = { new_dir->mnt, new_dentry }; + struct path_cond cond = { old_dentry->d_inode->i_uid, + old_dentry->d_inode->i_mode + }; + + error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0, + MAY_READ | AA_MAY_META_READ | MAY_WRITE | + AA_MAY_META_WRITE | AA_MAY_DELETE, + &cond); + if (!error) + error = aa_path_perm(OP_RENAME_DEST, profile, &new_path, + 0, MAY_WRITE | AA_MAY_META_WRITE | + AA_MAY_CREATE, &cond); + + } + return error; +} + +static int apparmor_path_chmod(struct dentry *dentry, struct vfsmount *mnt, + mode_t mode) +{ + if (!mediated_filesystem(dentry->d_inode)) + return 0; + + return common_perm_mnt_dentry(OP_CHMOD, mnt, dentry, AA_MAY_CHMOD); +} + +static int apparmor_path_chown(struct path *path, uid_t uid, gid_t gid) +{ + struct path_cond cond = { path->dentry->d_inode->i_uid, + path->dentry->d_inode->i_mode + }; + + if (!mediated_filesystem(path->dentry->d_inode)) + return 0; + + return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond); +} + +static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) +{ + if (!mediated_filesystem(dentry->d_inode)) + return 0; + + return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry, + AA_MAY_META_READ); +} + +static int apparmor_dentry_open(struct file *file, const struct cred *cred) +{ + struct aa_file_cxt *fcxt = file->f_security; + struct aa_profile *profile; + int error = 0; + + if (!mediated_filesystem(file->f_path.dentry->d_inode)) + return 0; + + /* If in exec, permission is handled by bprm hooks. + * Cache permissions granted by the previous exec check, with + * implicit read and executable mmap which are required to + * actually execute the image. + */ + if (current->in_execve) { + fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP; + return 0; + } + + profile = aa_cred_profile(cred); + if (!unconfined(profile)) { + struct inode *inode = file->f_path.dentry->d_inode; + struct path_cond cond = { inode->i_uid, inode->i_mode }; + + error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0, + aa_map_file_to_perms(file), &cond); + /* todo cache full allowed permissions set and state */ + fcxt->allow = aa_map_file_to_perms(file); + } + + return error; +} + +static int apparmor_file_alloc_security(struct file *file) +{ + /* freed by apparmor_file_free_security */ + file->f_security = aa_alloc_file_context(GFP_KERNEL); + if (!file->f_security) + return -ENOMEM; + return 0; + +} + +static void apparmor_file_free_security(struct file *file) +{ + struct aa_file_cxt *cxt = file->f_security; + + aa_free_file_context(cxt); +} + +static int common_file_perm(int op, struct file *file, u32 mask) +{ + struct aa_file_cxt *fcxt = file->f_security; + struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred); + int error = 0; + + BUG_ON(!fprofile); + + if (!file->f_path.mnt || + !mediated_filesystem(file->f_path.dentry->d_inode)) + return 0; + + profile = __aa_current_profile(); + + /* revalidate access, if task is unconfined, or the cached cred + * doesn't match or if the request is for more permissions than + * was granted. + * + * Note: the test for !unconfined(fprofile) is to handle file + * delegation from unconfined tasks + */ + if (!unconfined(profile) && !unconfined(fprofile) && + ((fprofile != profile) || (mask & ~fcxt->allow))) + error = aa_file_perm(op, profile, file, mask); + + return error; +} + +static int apparmor_file_permission(struct file *file, int mask) +{ + return common_file_perm(OP_FPERM, file, mask); +} + +static int apparmor_file_lock(struct file *file, unsigned int cmd) +{ + u32 mask = AA_MAY_LOCK; + + if (cmd == F_WRLCK) + mask |= MAY_WRITE; + + return common_file_perm(OP_FLOCK, file, mask); +} + +static int common_mmap(int op, struct file *file, unsigned long prot, + unsigned long flags) +{ + struct dentry *dentry; + int mask = 0; + + if (!file || !file->f_security) + return 0; + + if (prot & PROT_READ) + mask |= MAY_READ; + /* + * Private mappings don't require write perms since they don't + * write back to the files + */ + if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE)) + mask |= MAY_WRITE; + if (prot & PROT_EXEC) + mask |= AA_EXEC_MMAP; + + dentry = file->f_path.dentry; + return common_file_perm(op, file, mask); +} + +static int apparmor_file_mmap(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags, + unsigned long addr, unsigned long addr_only) +{ + int rc = 0; + + /* do DAC check */ + rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); + if (rc || addr_only) + return rc; + + return common_mmap(OP_FMMAP, file, prot, flags); +} + +static int apparmor_file_mprotect(struct vm_area_struct *vma, + unsigned long reqprot, unsigned long prot) +{ + return common_mmap(OP_FMPROT, vma->vm_file, prot, + !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0); +} + +static int apparmor_getprocattr(struct task_struct *task, char *name, + char **value) +{ + int error = -ENOENT; + struct aa_profile *profile; + /* released below */ + const struct cred *cred = get_task_cred(task); + struct aa_task_cxt *cxt = cred->security; + profile = aa_cred_profile(cred); + + if (strcmp(name, "current") == 0) + error = aa_getprocattr(aa_newest_version(cxt->profile), + value); + else if (strcmp(name, "prev") == 0 && cxt->previous) + error = aa_getprocattr(aa_newest_version(cxt->previous), + value); + else if (strcmp(name, "exec") == 0 && cxt->onexec) + error = aa_getprocattr(aa_newest_version(cxt->onexec), + value); + else + error = -EINVAL; + + put_cred(cred); + + return error; +} + +static int apparmor_setprocattr(struct task_struct *task, char *name, + void *value, size_t size) +{ + char *command, *args = value; + size_t arg_size; + int error; + + if (size == 0) + return -EINVAL; + /* args points to a PAGE_SIZE buffer, AppArmor requires that + * the buffer must be null terminated or have size <= PAGE_SIZE -1 + * so that AppArmor can null terminate them + */ + if (args[size - 1] != '\0') { + if (size == PAGE_SIZE) + return -EINVAL; + args[size] = '\0'; + } + + /* task can only write its own attributes */ + if (current != task) + return -EACCES; + + args = value; + args = strim(args); + command = strsep(&args, " "); + if (!args) + return -EINVAL; + args = skip_spaces(args); + if (!*args) + return -EINVAL; + + arg_size = size - (args - (char *) value); + if (strcmp(name, "current") == 0) { + if (strcmp(command, "changehat") == 0) { + error = aa_setprocattr_changehat(args, arg_size, + !AA_DO_TEST); + } else if (strcmp(command, "permhat") == 0) { + error = aa_setprocattr_changehat(args, arg_size, + AA_DO_TEST); + } else if (strcmp(command, "changeprofile") == 0) { + error = aa_setprocattr_changeprofile(args, !AA_ONEXEC, + !AA_DO_TEST); + } else if (strcmp(command, "permprofile") == 0) { + error = aa_setprocattr_changeprofile(args, !AA_ONEXEC, + AA_DO_TEST); + } else if (strcmp(command, "permipc") == 0) { + error = aa_setprocattr_permipc(args); + } else { + struct common_audit_data sa; + COMMON_AUDIT_DATA_INIT(&sa, NONE); + sa.aad.op = OP_SETPROCATTR; + sa.aad.info = name; + sa.aad.error = -EINVAL; + return aa_audit(AUDIT_APPARMOR_DENIED, NULL, GFP_KERNEL, + &sa, NULL); + } + } else if (strcmp(name, "exec") == 0) { + error = aa_setprocattr_changeprofile(args, AA_ONEXEC, + !AA_DO_TEST); + } else { + /* only support the "current" and "exec" process attributes */ + return -EINVAL; + } + if (!error) + error = size; + return error; +} + +static int apparmor_task_setrlimit(unsigned int resource, + struct rlimit *new_rlim) +{ + struct aa_profile *profile = aa_current_profile(); + int error = 0; + + if (!unconfined(profile)) + error = aa_task_setrlimit(profile, resource, new_rlim); + + return error; +} + +static struct security_operations apparmor_ops = { + .name = "apparmor", + + .ptrace_access_check = apparmor_ptrace_access_check, + .ptrace_traceme = apparmor_ptrace_traceme, + .capget = apparmor_capget, + .capable = apparmor_capable, + + .path_link = apparmor_path_link, + .path_unlink = apparmor_path_unlink, + .path_symlink = apparmor_path_symlink, + .path_mkdir = apparmor_path_mkdir, + .path_rmdir = apparmor_path_rmdir, + .path_mknod = apparmor_path_mknod, + .path_rename = apparmor_path_rename, + .path_chmod = apparmor_path_chmod, + .path_chown = apparmor_path_chown, + .path_truncate = apparmor_path_truncate, + .dentry_open = apparmor_dentry_open, + .inode_getattr = apparmor_inode_getattr, + + .file_permission = apparmor_file_permission, + .file_alloc_security = apparmor_file_alloc_security, + .file_free_security = apparmor_file_free_security, + .file_mmap = apparmor_file_mmap, + .file_mprotect = apparmor_file_mprotect, + .file_lock = apparmor_file_lock, + + .getprocattr = apparmor_getprocattr, + .setprocattr = apparmor_setprocattr, + + .cred_alloc_blank = apparmor_cred_alloc_blank, + .cred_free = apparmor_cred_free, + .cred_prepare = apparmor_cred_prepare, + .cred_transfer = apparmor_cred_transfer, + + .bprm_set_creds = apparmor_bprm_set_creds, + .bprm_committing_creds = apparmor_bprm_committing_creds, + .bprm_committed_creds = apparmor_bprm_committed_creds, + .bprm_secureexec = apparmor_bprm_secureexec, + + .task_setrlimit = apparmor_task_setrlimit, +}; + +/* + * AppArmor sysfs module parameters + */ + +static int param_set_aabool(const char *val, struct kernel_param *kp); +static int param_get_aabool(char *buffer, struct kernel_param *kp); +#define param_check_aabool(name, p) __param_check(name, p, int) + +static int param_set_aauint(const char *val, struct kernel_param *kp); +static int param_get_aauint(char *buffer, struct kernel_param *kp); +#define param_check_aauint(name, p) __param_check(name, p, int) + +static int param_set_aalockpolicy(const char *val, struct kernel_param *kp); +static int param_get_aalockpolicy(char *buffer, struct kernel_param *kp); +#define param_check_aalockpolicy(name, p) __param_check(name, p, int) + +static int param_set_audit(const char *val, struct kernel_param *kp); +static int param_get_audit(char *buffer, struct kernel_param *kp); +#define param_check_audit(name, p) __param_check(name, p, int) + +static int param_set_mode(const char *val, struct kernel_param *kp); +static int param_get_mode(char *buffer, struct kernel_param *kp); +#define param_check_mode(name, p) __param_check(name, p, int) + +/* Flag values, also controllable via /sys/module/apparmor/parameters + * We define special types as we want to do additional mediation. + */ + +/* AppArmor global enforcement switch - complain, enforce, kill */ +enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE; +module_param_call(mode, param_set_mode, param_get_mode, + &aa_g_profile_mode, S_IRUSR | S_IWUSR); + +/* Debug mode */ +int aa_g_debug; +module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR); + +/* Audit mode */ +enum audit_mode aa_g_audit; +module_param_call(audit, param_set_audit, param_get_audit, + &aa_g_audit, S_IRUSR | S_IWUSR); + +/* Determines if audit header is included in audited messages. This + * provides more context if the audit daemon is not running + */ +int aa_g_audit_header = 1; +module_param_named(audit_header, aa_g_audit_header, aabool, + S_IRUSR | S_IWUSR); + +/* lock out loading/removal of policy + * TODO: add in at boot loading of policy, which is the only way to + * load policy, if lock_policy is set + */ +int aa_g_lock_policy; +module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy, + S_IRUSR | S_IWUSR); + +/* Syscall logging mode */ +int aa_g_logsyscall; +module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR); + +/* Maximum pathname length before accesses will start getting rejected */ +unsigned int aa_g_path_max = 2 * PATH_MAX; +module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR); + +/* Determines how paranoid loading of policy is and how much verification + * on the loaded policy is done. + */ +int aa_g_paranoid_load = 1; +module_param_named(paranoid_load, aa_g_paranoid_load, aabool, + S_IRUSR | S_IWUSR); + +/* Boot time disable flag */ +static unsigned int apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE; +module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR); + +static int __init apparmor_enabled_setup(char *str) +{ + unsigned long enabled; + int error = strict_strtoul(str, 0, &enabled); + if (!error) + apparmor_enabled = enabled ? 1 : 0; + return 1; +} + +__setup("apparmor=", apparmor_enabled_setup); + +/* set global flag turning off the ability to load policy */ +static int param_set_aalockpolicy(const char *val, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + if (aa_g_lock_policy) + return -EACCES; + return param_set_bool(val, kp); +} + +static int param_get_aalockpolicy(char *buffer, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + return param_get_bool(buffer, kp); +} + +static int param_set_aabool(const char *val, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + return param_set_bool(val, kp); +} + +static int param_get_aabool(char *buffer, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + return param_get_bool(buffer, kp); +} + +static int param_set_aauint(const char *val, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + return param_set_uint(val, kp); +} + +static int param_get_aauint(char *buffer, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + return param_get_uint(buffer, kp); +} + +static int param_get_audit(char *buffer, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + if (!apparmor_enabled) + return -EINVAL; + + return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]); +} + +static int param_set_audit(const char *val, struct kernel_param *kp) +{ + int i; + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + if (!apparmor_enabled) + return -EINVAL; + + if (!val) + return -EINVAL; + + for (i = 0; i < AUDIT_MAX_INDEX; i++) { + if (strcmp(val, audit_mode_names[i]) == 0) { + aa_g_audit = i; + return 0; + } + } + + return -EINVAL; +} + +static int param_get_mode(char *buffer, struct kernel_param *kp) +{ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + if (!apparmor_enabled) + return -EINVAL; + + return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]); +} + +static int param_set_mode(const char *val, struct kernel_param *kp) +{ + int i; + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + if (!apparmor_enabled) + return -EINVAL; + + if (!val) + return -EINVAL; + + for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) { + if (strcmp(val, profile_mode_names[i]) == 0) { + aa_g_profile_mode = i; + return 0; + } + } + + return -EINVAL; +} + +/* + * AppArmor init functions + */ + +/** + * set_init_cxt - set a task context and profile on the first task. + * + * TODO: allow setting an alternate profile than unconfined + */ +static int __init set_init_cxt(void) +{ + struct cred *cred = (struct cred *)current->real_cred; + struct aa_task_cxt *cxt; + + cxt = aa_alloc_task_context(GFP_KERNEL); + if (!cxt) + return -ENOMEM; + + cxt->profile = aa_get_profile(root_ns->unconfined); + cred->security = cxt; + + return 0; +} + +static int __init apparmor_init(void) +{ + int error; + + if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) { + aa_info_message("AppArmor disabled by boot time parameter"); + apparmor_enabled = 0; + return 0; + } + + error = aa_alloc_root_ns(); + if (error) { + AA_ERROR("Unable to allocate default profile namespace\n"); + goto alloc_out; + } + + error = set_init_cxt(); + if (error) { + AA_ERROR("Failed to set context on init task\n"); + goto register_security_out; + } + + error = register_security(&apparmor_ops); + if (error) { + AA_ERROR("Unable to register AppArmor\n"); + goto register_security_out; + } + + /* Report that AppArmor successfully initialized */ + apparmor_initialized = 1; + if (aa_g_profile_mode == APPARMOR_COMPLAIN) + aa_info_message("AppArmor initialized: complain mode enabled"); + else if (aa_g_profile_mode == APPARMOR_KILL) + aa_info_message("AppArmor initialized: kill mode enabled"); + else + aa_info_message("AppArmor initialized"); + + return error; + +register_security_out: + aa_free_root_ns(); + +alloc_out: + aa_destroy_aafs(); + + apparmor_enabled = 0; + return error; + +} + +security_initcall(apparmor_init); -- 2.20.1