/* * 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 "include/af_unix.h" #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/net.h" #include "include/path.h" #include "include/policy.h" #include "include/procattr.h" #include "include/mount.h" /* Flag indicating whether initialization completed */ int apparmor_initialized __initdata; DEFINE_PER_CPU(struct aa_buffers, aa_buffers); /* * LSM hook functions */ /* * free the associated aa_task_cxt and put its labels */ static void apparmor_cred_free(struct cred *cred) { aa_free_task_context(cred_cxt(cred)); cred_cxt(cred) = 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_cxt(cred) = 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, cred_cxt(old)); cred_cxt(new) = 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 = cred_cxt(old); struct aa_task_cxt *new_cxt = cred_cxt(new); aa_dup_task_context(new_cxt, old_cxt); } static int apparmor_ptrace_access_check(struct task_struct *child, unsigned int mode) { struct aa_label *tracer, *tracee; int error = cap_ptrace_access_check(child, mode); if (error) return error; tracer = aa_current_label(); tracee = aa_get_task_label(child); error = aa_may_ptrace(tracer, tracee, mode == PTRACE_MODE_READ ? AA_PTRACE_READ : AA_PTRACE_TRACE); aa_put_label(tracee); return error; } static int apparmor_ptrace_traceme(struct task_struct *parent) { struct aa_label *tracer, *tracee; int error = cap_ptrace_traceme(parent); if (error) return error; tracee = aa_current_label(); tracer = aa_get_task_label(parent); error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE); aa_put_label(tracer); return error; } /* 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_label *label; const struct cred *cred; rcu_read_lock(); cred = __task_cred(target); label = aa_get_newest_cred_label(cred); *effective = cred->cap_effective; *inheritable = cred->cap_inheritable; *permitted = cred->cap_permitted; if (!unconfined(label)) { struct aa_profile *profile; struct label_it i; label_for_each_confined(i, label, profile) { if (COMPLAIN_MODE(profile)) continue; *effective = cap_intersect(*effective, profile->caps.allow); *permitted = cap_intersect(*permitted, profile->caps.allow); } } rcu_read_unlock(); aa_put_label(label); return 0; } static int apparmor_capable(const struct cred *cred, struct user_namespace *ns, int cap, int audit) { struct aa_label *label; /* cap_capable returns 0 on success, else -EPERM */ int error = cap_capable(cred, ns, cap, audit); if (error) return error; label = aa_get_newest_cred_label(cred); if (!unconfined(label)) error = aa_capable(label, cap, audit); aa_put_label(label); 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_label *label; int error = 0; label = aa_begin_current_label(); if (!unconfined(label)) error = aa_path_perm(op, label, path, 0, mask, cond); aa_end_current_label(label); return error; } static int common_perm_cond(int op, struct path *path, u32 mask) { struct path_cond cond = { path->dentry->d_inode->i_uid, path->dentry->d_inode->i_mode }; return common_perm(op, path, mask, &cond); } static void apparmor_inode_free_security(struct inode *inode) { struct aa_label *cxt = inode_cxt(inode); if (cxt) { inode_cxt(inode) = NULL; aa_put_label(cxt); } } /** * 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 }; return common_perm_cond(op, &path, mask); } /** * 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 || !path_mediated_fs(dentry)) 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 || !path_mediated_fs(dir->dentry)) 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, umode_t 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, umode_t mode, unsigned int dev) { return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode); } static int apparmor_path_truncate(struct path *path) { if (!path->mnt || !path_mediated_fs(path->dentry)) return 0; return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR); } 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_label *label; int error = 0; if (!path_mediated_fs(old_dentry)) return 0; label = aa_current_label(); if (!unconfined(label)) error = aa_path_link(label, 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_label *label; int error = 0; if (!path_mediated_fs(old_dentry)) return 0; label = aa_current_label(); if (!unconfined(label)) { 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, label, &old_path, 0, MAY_READ | AA_MAY_GETATTR | MAY_WRITE | AA_MAY_SETATTR | AA_MAY_DELETE, &cond); if (!error) error = aa_path_perm(OP_RENAME_DEST, label, &new_path, 0, MAY_WRITE | AA_MAY_SETATTR | AA_MAY_CREATE, &cond); } return error; } static int apparmor_path_chmod(struct path *path, umode_t mode) { if (!path_mediated_fs(path->dentry)) return 0; return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD); } static int apparmor_path_chown(struct path *path, kuid_t uid, kgid_t gid) { if (!path_mediated_fs(path->dentry)) return 0; return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN); } static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) { if (!path_mediated_fs(dentry)) return 0; return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry, AA_MAY_GETATTR); } static int apparmor_file_open(struct file *file, const struct cred *cred) { struct aa_file_cxt *fcxt = file_cxt(file); struct aa_label *label; int error = 0; if (!path_mediated_fs(file->f_path.dentry)) 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; } label = aa_get_newest_cred_label(cred); if (!unconfined(label)) { struct inode *inode = file_inode(file); struct path_cond cond = { inode->i_uid, inode->i_mode }; error = aa_path_perm(OP_OPEN, label, &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); } aa_put_label(label); return error; } static int apparmor_file_alloc_security(struct file *file) { /* freed by apparmor_file_free_security */ file->f_security = aa_alloc_file_cxt(aa_current_label(), GFP_KERNEL); if (!file_cxt(file)) return -ENOMEM; return 0; } static void apparmor_file_free_security(struct file *file) { aa_free_file_cxt(file_cxt(file)); } static int common_file_perm(int op, struct file *file, u32 mask) { struct aa_label *label; int error = 0; label = aa_begin_current_label(); error = aa_file_perm(op, label, file, mask); aa_end_current_label(label); return error; } static int apparmor_file_receive(struct file *file) { return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file)); } 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) { int mask = 0; if (!file || !file_cxt(file)) 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; return common_file_perm(op, file, mask); } static int apparmor_mmap_file(struct file *file, unsigned long reqprot, unsigned long prot, unsigned long flags) { 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_sb_mount(const char *dev_name, struct path *path, const char *type, unsigned long flags, void *data) { struct aa_label *label; int error = 0; /* Discard magic */ if ((flags & MS_MGC_MSK) == MS_MGC_VAL) flags &= ~MS_MGC_MSK; flags &= ~AA_MS_IGNORE_MASK; label = aa_begin_current_label(); if (!unconfined(label)) { if (flags & MS_REMOUNT) error = aa_remount(label, path, flags, data); else if (flags & MS_BIND) error = aa_bind_mount(label, path, dev_name, flags); else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE)) error = aa_mount_change_type(label, path, flags); else if (flags & MS_MOVE) error = aa_move_mount(label, path, dev_name); else error = aa_new_mount(label, dev_name, path, type, flags, data); } aa_end_current_label(label); return error; } static int apparmor_sb_umount(struct vfsmount *mnt, int flags) { struct aa_label *label; int error = 0; label = aa_begin_current_label(); if (!unconfined(label)) error = aa_umount(label, mnt, flags); aa_end_current_label(label); return error; } static int apparmor_sb_pivotroot(struct path *old_path, struct path *new_path) { struct aa_label *label; int error = 0; label = aa_begin_current_label(); if (!unconfined(label)) error = aa_pivotroot(label, old_path, new_path); aa_end_current_label(label); return error; } static int apparmor_getprocattr(struct task_struct *task, char *name, char **value) { int error = -ENOENT; /* released below */ const struct cred *cred = get_task_cred(task); struct aa_task_cxt *cxt = cred_cxt(cred); struct aa_label *label = NULL; if (strcmp(name, "current") == 0) label = aa_get_newest_label(cxt->label); else if (strcmp(name, "prev") == 0 && cxt->previous) label = aa_get_newest_label(cxt->previous); else if (strcmp(name, "exec") == 0 && cxt->onexec) label = aa_get_newest_label(cxt->onexec); else error = -EINVAL; if (label) error = aa_getprocattr(label, value); aa_put_label(label); 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; DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR); 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 goto fail; } else if (strcmp(name, "exec") == 0) { if (strcmp(command, "exec") == 0) error = aa_setprocattr_changeprofile(args, AA_ONEXEC, !AA_DO_TEST); else goto fail; } else /* only support the "current" and "exec" process attributes */ return -EINVAL; if (!error) error = size; return error; fail: aad(&sa)->label = aa_current_label(); aad(&sa)->info = name; aad(&sa)->error = -EINVAL; aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL); return -EINVAL; } /** * apparmor_bprm_committing_creds - do task cleanup on committing new creds * @bprm: binprm for the exec (NOT NULL) */ void apparmor_bprm_committing_creds(struct linux_binprm *bprm) { struct aa_label *label = aa_current_raw_label(); struct aa_task_cxt *new_cxt = cred_cxt(bprm->cred); /* bail out if unconfined or not changing profile */ if ((new_cxt->label->replacedby == label->replacedby) || (unconfined(new_cxt->label))) return; aa_inherit_files(bprm->cred, current->files); current->pdeath_signal = 0; /* reset soft limits and set hard limits for the new label */ __aa_transition_rlimits(label, new_cxt->label); } /** * apparmor_bprm_commited_cred - do cleanup after new creds committed * @bprm: binprm for the exec (NOT NULL) */ void apparmor_bprm_committed_creds(struct linux_binprm *bprm) { /* TODO: cleanup signals - ipc mediation */ return; } static int apparmor_task_setrlimit(struct task_struct *task, unsigned int resource, struct rlimit *new_rlim) { struct aa_label *label = aa_begin_current_label(); int error = 0; if (!unconfined(label)) error = aa_task_setrlimit(label, task, resource, new_rlim); aa_end_current_label(label); return error; } /** * apparmor_sk_alloc_security - allocate and attach the sk_security field */ static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags) { struct aa_sk_cxt *cxt; cxt = kzalloc(sizeof(*cxt), flags); if (!cxt) return -ENOMEM; SK_CXT(sk) = cxt; //??? set local too current??? return 0; } /** * apparmor_sk_free_security - free the sk_security field */ static void apparmor_sk_free_security(struct sock *sk) { struct aa_sk_cxt *cxt = SK_CXT(sk); SK_CXT(sk) = NULL; aa_put_label(cxt->label); aa_put_label(cxt->peer); kfree(cxt); } /** * apparmor_clone_security - clone the sk_security field */ static void apparmor_sk_clone_security(const struct sock *sk, struct sock *newsk) { struct aa_sk_cxt *cxt = SK_CXT(sk); struct aa_sk_cxt *new = SK_CXT(newsk); new->label = aa_get_label(cxt->label); new->peer = aa_get_label(cxt->peer); } /** * apparmor_unix_stream_connect - check perms before making unix domain conn * * peer is locked when this hook is called */ static int apparmor_unix_stream_connect(struct sock *sk, struct sock *peer_sk, struct sock *newsk) { struct aa_sk_cxt *sk_cxt = SK_CXT(sk); struct aa_sk_cxt *peer_cxt = SK_CXT(peer_sk); struct aa_sk_cxt *new_cxt = SK_CXT(newsk); struct aa_label *label; int error; label = aa_begin_current_label(); error = aa_unix_peer_perm(label, OP_CONNECT, (AA_MAY_CONNECT | AA_MAY_SEND | AA_MAY_RECEIVE), sk, peer_sk, NULL); if (!UNIX_FS(peer_sk)) { last_error(error, aa_unix_peer_perm(peer_cxt->label, OP_CONNECT, (AA_MAY_ACCEPT | AA_MAY_SEND | AA_MAY_RECEIVE), peer_sk, sk, label)); } aa_end_current_label(label); if (error) return error; /* label newsk if it wasn't labeled in post_create. Normally this * would be done in sock_graft, but because we are directly looking * at the peer_sk to obtain peer_labeling for unix socks this * does not work */ if (!new_cxt->label) new_cxt->label = aa_get_label(peer_cxt->label); /* Cross reference the peer labels for SO_PEERSEC */ if (new_cxt->peer) aa_put_label(new_cxt->peer); if (sk_cxt->peer) aa_put_label(sk_cxt->peer); new_cxt->peer = aa_get_label(sk_cxt->label); sk_cxt->peer = aa_get_label(peer_cxt->label); return 0; } /** * apparmor_unix_may_send - check perms before conn or sending unix dgrams * * other is locked when this hook is called * * dgram connect calls may_send, peer setup but path not copied????? */ static int apparmor_unix_may_send(struct socket *sock, struct socket *peer) { struct aa_sk_cxt *peer_cxt = SK_CXT(peer->sk); struct aa_label *label = aa_begin_current_label(); int error; error = xcheck(aa_unix_peer_perm(label, OP_SENDMSG, AA_MAY_SEND, sock->sk, peer->sk, NULL), aa_unix_peer_perm(peer_cxt->label, OP_SENDMSG, AA_MAY_RECEIVE, peer->sk, sock->sk, label)); aa_end_current_label(label); return error; } /** * apparmor_socket_create - check perms before creating a new socket */ static int apparmor_socket_create(int family, int type, int protocol, int kern) { struct aa_label *label; label = aa_current_label(); if (kern || unconfined(label)) return 0; return aa_sock_create_perm(label, family, type, protocol); } /** * apparmor_socket_post_create - setup the per-socket security struct * * Note: * - kernel sockets currently labeled unconfined but we may want to * move to a special kernel label * - socket may not have sk here if created with sock_create_lite or * sock_alloc. These should be accept cases which will be handled in * sock_graft. */ static int apparmor_socket_post_create(struct socket *sock, int family, int type, int protocol, int kern) { struct aa_label *label; if (kern) label = aa_get_label(¤t_ns()->unconfined->label); else label = aa_get_label(aa_current_label()); if (sock->sk) { struct aa_sk_cxt *cxt = SK_CXT(sock->sk); aa_put_label(cxt->label); cxt->label = aa_get_label(label); } aa_put_label(label); return 0; } /** * apparmor_socket_bind - check perms before bind addr to socket */ static int apparmor_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) { return aa_sock_bind_perm(sock, address, addrlen); } /** * apparmor_socket_connect - check perms before connecting @sock to @address */ static int apparmor_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) { return aa_sock_connect_perm(sock, address, addrlen); } /** * apparmor_socket_list - check perms before allowing listen */ static int apparmor_socket_listen(struct socket *sock, int backlog) { return aa_sock_listen_perm(sock, backlog); } /** * apparmor_socket_accept - check perms before accepting a new connection. * * Note: while @newsock is created and has some information, the accept * has not been done. */ static int apparmor_socket_accept(struct socket *sock, struct socket *newsock) { return aa_sock_accept_perm(sock, newsock); } /** * apparmor_socket_sendmsg - check perms before sending msg to another socket */ static int apparmor_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) { int error = aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size); if (!error) { /* TODO: setup delegation on scm rights see smack for AF_INET, AF_INET6 */ ; } return error; } /** * apparmor_socket_recvmsg - check perms before receiving a message */ static int apparmor_socket_recvmsg(struct socket *sock, struct msghdr *msg, int size, int flags) { return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size); } /** * apparmor_socket_getsockname - check perms before getting the local address */ static int apparmor_socket_getsockname(struct socket *sock) { return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock); } /** * apparmor_socket_getpeername - check perms before getting remote address */ static int apparmor_socket_getpeername(struct socket *sock) { return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock); } /** * apparmor_getsockopt - check perms before getting socket options */ static int apparmor_socket_getsockopt(struct socket *sock, int level, int optname) { return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock, level, optname); } /** * apparmor_setsockopt - check perms before setting socket options */ static int apparmor_socket_setsockopt(struct socket *sock, int level, int optname) { return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock, level, optname); } /** * apparmor_socket_shutdown - check perms before shutting down @sock conn */ static int apparmor_socket_shutdown(struct socket *sock, int how) { return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock); } /** * apparmor_socket_sock_recv_skb - check perms before associating skb to sk * * Note: can not sleep maybe called with locks held dont want protocol specific in __skb_recv_datagram() to deny an incoming connection socket_sock_rcv_skb() */ static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) { /* TODO: */ return 0; } static struct aa_label *sk_peer_label(struct sock *sk) { struct sock *peer_sk; struct aa_sk_cxt *cxt = SK_CXT(sk); if (cxt->peer) return cxt->peer; if (sk->sk_family != PF_UNIX) return ERR_PTR(-ENOPROTOOPT); /* check for sockpair peering which does not go through * security_unix_stream_connect */ peer_sk = unix_peer(sk); if (peer_sk) { cxt = SK_CXT(peer_sk); if (cxt->label) return cxt->label; } return ERR_PTR(-ENOPROTOOPT); } /** * apparmor_socket_getpeersec_stream - get security context of peer * * Note: for tcp only valid if using ipsec or cipso on lan */ static int apparmor_socket_getpeersec_stream(struct socket *sock, char __user *optval, int __user *optlen, unsigned len) { char *name; int slen, error = 0; struct aa_label *label = aa_current_label(); struct aa_label *peer = sk_peer_label(sock->sk); if (IS_ERR(peer)) return PTR_ERR(peer); slen = aa_label_asprint(&name, labels_ns(label), peer, true, GFP_KERNEL); /* don't include terminating \0 in slen, it breaks some apps */ if (slen < 0) { error = -ENOMEM; } else { if (slen > len) { error = -ERANGE; } else if (copy_to_user(optval, name, slen)) { error = -EFAULT; goto out; } if (put_user(slen, optlen)) error = -EFAULT; out: kfree(name); } return error; } /** * apparmor_socket_getpeersec_dgram - get security label of packet * @sock: the peer socket * @skb: packet data * @secid: pointer to where to put the secid of the packet * * Sets the netlabel socket state on sk from parent */ static int apparmor_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) { /* TODO: requires secid support, and netlabel */ return -ENOPROTOOPT; } /** * apparmor_sock_graft - Initialize newly created socket * @sk: child sock * @parent: parent socket * * Note: could set off of SOCK_CXT(parent) but need to track inode and we can * just set sk security information off of current creating process label * Labeling of sk for accept case - probably should be sock based * instead of task, because of the case where an implicitly labeled * socket is shared by different tasks. */ static void apparmor_sock_graft(struct sock *sk, struct socket *parent) { struct aa_sk_cxt *cxt = SK_CXT(sk); if (!cxt->label) cxt->label = aa_get_current_label(); } static int apparmor_task_kill(struct task_struct *target, struct siginfo *info, int sig, u32 secid) { struct aa_label *cl, *tl; int error; if (secid) /* TODO: after secid to label mapping is done. * Dealing with USB IO specific behavior */ return 0; cl = aa_begin_current_label(); tl = aa_get_task_label(target); error = aa_may_signal(cl, tl, sig); aa_put_label(tl); aa_end_current_label(cl); 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, .inode_free_security = apparmor_inode_free_security, .sb_mount = apparmor_sb_mount, .sb_umount = apparmor_sb_umount, .sb_pivotroot = apparmor_sb_pivotroot, .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, .inode_getattr = apparmor_inode_getattr, .file_open = apparmor_file_open, .file_receive = apparmor_file_receive, .file_permission = apparmor_file_permission, .file_alloc_security = apparmor_file_alloc_security, .file_free_security = apparmor_file_free_security, .mmap_file = apparmor_mmap_file, .mmap_addr = cap_mmap_addr, .file_mprotect = apparmor_file_mprotect, .file_lock = apparmor_file_lock, .getprocattr = apparmor_getprocattr, .setprocattr = apparmor_setprocattr, .sk_alloc_security = apparmor_sk_alloc_security, .sk_free_security = apparmor_sk_free_security, .sk_clone_security = apparmor_sk_clone_security, .unix_stream_connect = apparmor_unix_stream_connect, .unix_may_send = apparmor_unix_may_send, .socket_create = apparmor_socket_create, .socket_post_create = apparmor_socket_post_create, .socket_bind = apparmor_socket_bind, .socket_connect = apparmor_socket_connect, .socket_listen = apparmor_socket_listen, .socket_accept = apparmor_socket_accept, .socket_sendmsg = apparmor_socket_sendmsg, .socket_recvmsg = apparmor_socket_recvmsg, .socket_getsockname = apparmor_socket_getsockname, .socket_getpeername = apparmor_socket_getpeername, .socket_getsockopt = apparmor_socket_getsockopt, .socket_setsockopt = apparmor_socket_setsockopt, .socket_shutdown = apparmor_socket_shutdown, .socket_sock_rcv_skb = apparmor_socket_sock_rcv_skb, .socket_getpeersec_stream = apparmor_socket_getpeersec_stream, .socket_getpeersec_dgram = apparmor_socket_getpeersec_dgram, .sock_graft = apparmor_sock_graft, .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, .task_kill = apparmor_task_kill, }; /* * AppArmor sysfs module parameters */ static int param_set_aabool(const char *val, const struct kernel_param *kp); static int param_get_aabool(char *buffer, const struct kernel_param *kp); #define param_check_aabool param_check_bool static struct kernel_param_ops param_ops_aabool = { .set = param_set_aabool, .get = param_get_aabool }; static int param_set_aauint(const char *val, const struct kernel_param *kp); static int param_get_aauint(char *buffer, const struct kernel_param *kp); #define param_check_aauint param_check_uint static struct kernel_param_ops param_ops_aauint = { .set = param_set_aauint, .get = param_get_aauint }; static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp); static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp); #define param_check_aalockpolicy param_check_bool static struct kernel_param_ops param_ops_aalockpolicy = { .set = param_set_aalockpolicy, .get = param_get_aalockpolicy }; static int param_set_audit(const char *val, struct kernel_param *kp); static int param_get_audit(char *buffer, struct kernel_param *kp); static int param_set_mode(const char *val, struct kernel_param *kp); static int param_get_mode(char *buffer, struct kernel_param *kp); /* 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); /* whether policy verification hashing is enabled */ bool aa_g_hash_policy = CONFIG_SECURITY_APPARMOR_HASH_DEFAULT; module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR); /* Debug mode */ bool 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 */ bool 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 */ bool aa_g_lock_policy; module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy, S_IRUSR | S_IWUSR); /* Syscall logging mode */ bool 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. */ bool aa_g_paranoid_load = 1; module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUSR | S_IWUSR); /* Boot time disable flag */ static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE; module_param_named(enabled, apparmor_enabled, bool, S_IRUGO); /* Boot time to set use of default or unconfined as initial profile */ bool aa_g_unconfined_init = CONFIG_SECURITY_APPARMOR_UNCONFINED_INIT; module_param_named(unconfined, aa_g_unconfined_init, bool, S_IRUSR); static int __init apparmor_enabled_setup(char *str) { unsigned long enabled; int error = kstrtoul(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, const 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, const 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, const struct kernel_param *kp) { if (!capable(CAP_MAC_ADMIN)) return -EPERM; return param_set_bool(val, kp); } static int param_get_aabool(char *buffer, const 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, const struct kernel_param *kp) { if (!capable(CAP_MAC_ADMIN)) return -EPERM; return param_set_uint(val, kp); } static int param_get_aauint(char *buffer, const 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", aa_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_MODE_NAMES_MAX_INDEX; i++) { if (strcmp(val, aa_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. */ 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; if (!aa_g_unconfined_init) { cxt->label = aa_setup_default_label(); if (!cxt->label) { aa_free_task_context(cxt); return -ENOMEM; } /* fs setup of default is done in aa_create_aafs() */ } else cxt->label = aa_get_label(&root_ns->unconfined->label); cred_cxt(cred) = cxt; return 0; } static void destroy_buffers(void) { u32 i, j; for_each_possible_cpu(i) { for_each_cpu_buffer(j) { kfree(per_cpu(aa_buffers, i).buf[j]); per_cpu(aa_buffers, i).buf[j] = NULL; } } } static int __init alloc_buffers(void) { u32 i, j; for_each_possible_cpu(i) { for_each_cpu_buffer(j) { char *buffer; if (cpu_to_node(i) > num_online_nodes()) /* fallback to kmalloc for offline nodes */ buffer = kmalloc(aa_g_path_max, GFP_KERNEL); else buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL, cpu_to_node(i)); if (!buffer) { destroy_buffers(); return -ENOMEM; } per_cpu(aa_buffers, i).buf[j] = buffer; } } 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 = alloc_buffers(); if (error) { AA_ERROR("Unable to allocate work buffers\n"); goto buffers_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) { struct cred *cred = (struct cred *)current->real_cred; aa_free_task_context(cred_cxt(cred)); cred_cxt(cred) = NULL; 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(); buffers_out: destroy_buffers(); alloc_out: aa_destroy_aafs(); apparmor_enabled = 0; return error; } security_initcall(apparmor_init);