WSL2-Linux-Kernel/security/security.c

1156 строки
29 KiB
C
Исходник Обычный вид История

/*
* Security plug functions
*
* Copyright (C) 2001 WireX Communications, Inc <chris@wirex.com>
* Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2001 Networks Associates Technology, Inc <ssmalley@nai.com>
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/security.h>
/* Boot-time LSM user choice */
static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1];
/* things that live in capability.c */
extern struct security_operations default_security_ops;
extern void security_fixup_ops(struct security_operations *ops);
struct security_operations *security_ops; /* Initialized to NULL */
/* amount of vm to protect from userspace access */
unsigned long mmap_min_addr = CONFIG_SECURITY_DEFAULT_MMAP_MIN_ADDR;
static inline int verify(struct security_operations *ops)
{
/* verify the security_operations structure exists */
if (!ops)
return -EINVAL;
security_fixup_ops(ops);
return 0;
}
static void __init do_security_initcalls(void)
{
initcall_t *call;
call = __security_initcall_start;
while (call < __security_initcall_end) {
(*call) ();
call++;
}
}
/**
* security_init - initializes the security framework
*
* This should be called early in the kernel initialization sequence.
*/
int __init security_init(void)
{
printk(KERN_INFO "Security Framework initialized\n");
security_fixup_ops(&default_security_ops);
security_ops = &default_security_ops;
do_security_initcalls();
return 0;
}
/* Save user chosen LSM */
static int __init choose_lsm(char *str)
{
strncpy(chosen_lsm, str, SECURITY_NAME_MAX);
return 1;
}
__setup("security=", choose_lsm);
/**
* security_module_enable - Load given security module on boot ?
* @ops: a pointer to the struct security_operations that is to be checked.
*
* Each LSM must pass this method before registering its own operations
* to avoid security registration races. This method may also be used
* to check if your LSM is currently loaded during kernel initialization.
*
* Return true if:
* -The passed LSM is the one chosen by user at boot time,
* -or user didsn't specify a specific LSM and we're the first to ask
* for registeration permissoin,
* -or the passed LSM is currently loaded.
* Otherwise, return false.
*/
int __init security_module_enable(struct security_operations *ops)
{
if (!*chosen_lsm)
strncpy(chosen_lsm, ops->name, SECURITY_NAME_MAX);
else if (strncmp(ops->name, chosen_lsm, SECURITY_NAME_MAX))
return 0;
return 1;
}
/**
* register_security - registers a security framework with the kernel
* @ops: a pointer to the struct security_options that is to be registered
*
* This function is to allow a security module to register itself with the
* kernel security subsystem. Some rudimentary checking is done on the @ops
* value passed to this function. You'll need to check first if your LSM
* is allowed to register its @ops by calling security_module_enable(@ops).
*
* If there is already a security module registered with the kernel,
* an error will be returned. Otherwise 0 is returned on success.
*/
int register_security(struct security_operations *ops)
{
if (verify(ops)) {
printk(KERN_DEBUG "%s could not verify "
"security_operations structure.\n", __func__);
return -EINVAL;
}
if (security_ops != &default_security_ops)
return -EAGAIN;
security_ops = ops;
return 0;
}
/* Security operations */
Security: split proc ptrace checking into read vs. attach Enable security modules to distinguish reading of process state via proc from full ptrace access by renaming ptrace_may_attach to ptrace_may_access and adding a mode argument indicating whether only read access or full attach access is requested. This allows security modules to permit access to reading process state without granting full ptrace access. The base DAC/capability checking remains unchanged. Read access to /proc/pid/mem continues to apply a full ptrace attach check since check_mem_permission() already requires the current task to already be ptracing the target. The other ptrace checks within proc for elements like environ, maps, and fds are changed to pass the read mode instead of attach. In the SELinux case, we model such reading of process state as a reading of a proc file labeled with the target process' label. This enables SELinux policy to permit such reading of process state without permitting control or manipulation of the target process, as there are a number of cases where programs probe for such information via proc but do not need to be able to control the target (e.g. procps, lsof, PolicyKit, ConsoleKit). At present we have to choose between allowing full ptrace in policy (more permissive than required/desired) or breaking functionality (or in some cases just silencing the denials via dontaudit rules but this can hide genuine attacks). This version of the patch incorporates comments from Casey Schaufler (change/replace existing ptrace_may_attach interface, pass access mode), and Chris Wright (provide greater consistency in the checking). Note that like their predecessors __ptrace_may_attach and ptrace_may_attach, the __ptrace_may_access and ptrace_may_access interfaces use different return value conventions from each other (0 or -errno vs. 1 or 0). I retained this difference to avoid any changes to the caller logic but made the difference clearer by changing the latter interface to return a bool rather than an int and by adding a comment about it to ptrace.h for any future callers. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: James Morris <jmorris@namei.org>
2008-05-19 16:32:49 +04:00
int security_ptrace(struct task_struct *parent, struct task_struct *child,
unsigned int mode)
{
Security: split proc ptrace checking into read vs. attach Enable security modules to distinguish reading of process state via proc from full ptrace access by renaming ptrace_may_attach to ptrace_may_access and adding a mode argument indicating whether only read access or full attach access is requested. This allows security modules to permit access to reading process state without granting full ptrace access. The base DAC/capability checking remains unchanged. Read access to /proc/pid/mem continues to apply a full ptrace attach check since check_mem_permission() already requires the current task to already be ptracing the target. The other ptrace checks within proc for elements like environ, maps, and fds are changed to pass the read mode instead of attach. In the SELinux case, we model such reading of process state as a reading of a proc file labeled with the target process' label. This enables SELinux policy to permit such reading of process state without permitting control or manipulation of the target process, as there are a number of cases where programs probe for such information via proc but do not need to be able to control the target (e.g. procps, lsof, PolicyKit, ConsoleKit). At present we have to choose between allowing full ptrace in policy (more permissive than required/desired) or breaking functionality (or in some cases just silencing the denials via dontaudit rules but this can hide genuine attacks). This version of the patch incorporates comments from Casey Schaufler (change/replace existing ptrace_may_attach interface, pass access mode), and Chris Wright (provide greater consistency in the checking). Note that like their predecessors __ptrace_may_attach and ptrace_may_attach, the __ptrace_may_access and ptrace_may_access interfaces use different return value conventions from each other (0 or -errno vs. 1 or 0). I retained this difference to avoid any changes to the caller logic but made the difference clearer by changing the latter interface to return a bool rather than an int and by adding a comment about it to ptrace.h for any future callers. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: James Morris <jmorris@namei.org>
2008-05-19 16:32:49 +04:00
return security_ops->ptrace(parent, child, mode);
}
int security_capget(struct task_struct *target,
kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted)
{
return security_ops->capget(target, effective, inheritable, permitted);
}
int security_capset_check(struct task_struct *target,
kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted)
{
return security_ops->capset_check(target, effective, inheritable, permitted);
}
void security_capset_set(struct task_struct *target,
kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted)
{
security_ops->capset_set(target, effective, inheritable, permitted);
}
int security_capable(struct task_struct *tsk, int cap)
{
return security_ops->capable(tsk, cap);
}
int security_acct(struct file *file)
{
return security_ops->acct(file);
}
int security_sysctl(struct ctl_table *table, int op)
{
return security_ops->sysctl(table, op);
}
int security_quotactl(int cmds, int type, int id, struct super_block *sb)
{
return security_ops->quotactl(cmds, type, id, sb);
}
int security_quota_on(struct dentry *dentry)
{
return security_ops->quota_on(dentry);
}
int security_syslog(int type)
{
return security_ops->syslog(type);
}
int security_settime(struct timespec *ts, struct timezone *tz)
{
return security_ops->settime(ts, tz);
}
int security_vm_enough_memory(long pages)
{
return security_ops->vm_enough_memory(current->mm, pages);
}
int security_vm_enough_memory_mm(struct mm_struct *mm, long pages)
{
return security_ops->vm_enough_memory(mm, pages);
}
int security_bprm_alloc(struct linux_binprm *bprm)
{
return security_ops->bprm_alloc_security(bprm);
}
void security_bprm_free(struct linux_binprm *bprm)
{
security_ops->bprm_free_security(bprm);
}
void security_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
{
security_ops->bprm_apply_creds(bprm, unsafe);
}
void security_bprm_post_apply_creds(struct linux_binprm *bprm)
{
security_ops->bprm_post_apply_creds(bprm);
}
int security_bprm_set(struct linux_binprm *bprm)
{
return security_ops->bprm_set_security(bprm);
}
int security_bprm_check(struct linux_binprm *bprm)
{
return security_ops->bprm_check_security(bprm);
}
int security_bprm_secureexec(struct linux_binprm *bprm)
{
return security_ops->bprm_secureexec(bprm);
}
int security_sb_alloc(struct super_block *sb)
{
return security_ops->sb_alloc_security(sb);
}
void security_sb_free(struct super_block *sb)
{
security_ops->sb_free_security(sb);
}
int security_sb_copy_data(char *orig, char *copy)
{
return security_ops->sb_copy_data(orig, copy);
}
EXPORT_SYMBOL(security_sb_copy_data);
int security_sb_kern_mount(struct super_block *sb, void *data)
{
return security_ops->sb_kern_mount(sb, data);
}
int security_sb_show_options(struct seq_file *m, struct super_block *sb)
{
return security_ops->sb_show_options(m, sb);
}
int security_sb_statfs(struct dentry *dentry)
{
return security_ops->sb_statfs(dentry);
}
int security_sb_mount(char *dev_name, struct path *path,
char *type, unsigned long flags, void *data)
{
return security_ops->sb_mount(dev_name, path, type, flags, data);
}
int security_sb_check_sb(struct vfsmount *mnt, struct path *path)
{
return security_ops->sb_check_sb(mnt, path);
}
int security_sb_umount(struct vfsmount *mnt, int flags)
{
return security_ops->sb_umount(mnt, flags);
}
void security_sb_umount_close(struct vfsmount *mnt)
{
security_ops->sb_umount_close(mnt);
}
void security_sb_umount_busy(struct vfsmount *mnt)
{
security_ops->sb_umount_busy(mnt);
}
void security_sb_post_remount(struct vfsmount *mnt, unsigned long flags, void *data)
{
security_ops->sb_post_remount(mnt, flags, data);
}
void security_sb_post_addmount(struct vfsmount *mnt, struct path *mountpoint)
{
security_ops->sb_post_addmount(mnt, mountpoint);
}
int security_sb_pivotroot(struct path *old_path, struct path *new_path)
{
return security_ops->sb_pivotroot(old_path, new_path);
}
void security_sb_post_pivotroot(struct path *old_path, struct path *new_path)
{
security_ops->sb_post_pivotroot(old_path, new_path);
}
Security: add get, set, and cloning of superblock security information Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow filesystems to directly own and control all of their mount options if they so choose. This interface deals only with option identifiers and strings so it should generic enough for any LSM which may come in the future. Filesystems which pass text mount data around in the kernel (almost all of them) need not currently make use of this interface when dealing with SELinux since it will still parse those strings as it always has. I assume future LSM's would do the same. NFS is the primary FS which does not use text mount data and thus must make use of this interface. An LSM would need to implement these functions only if they had mount time options, such as selinux has context= or fscontext=. If the LSM has no mount time options they could simply not implement and let the dummy ops take care of things. An LSM other than SELinux would need to define new option numbers in security.h and any FS which decides to own there own security options would need to be patched to use this new interface for every possible LSM. This is because it was stated to me very clearly that LSM's should not attempt to understand FS mount data and the burdon to understand security should be in the FS which owns the options. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2007-11-30 21:00:35 +03:00
int security_sb_set_mnt_opts(struct super_block *sb,
struct security_mnt_opts *opts)
Security: add get, set, and cloning of superblock security information Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow filesystems to directly own and control all of their mount options if they so choose. This interface deals only with option identifiers and strings so it should generic enough for any LSM which may come in the future. Filesystems which pass text mount data around in the kernel (almost all of them) need not currently make use of this interface when dealing with SELinux since it will still parse those strings as it always has. I assume future LSM's would do the same. NFS is the primary FS which does not use text mount data and thus must make use of this interface. An LSM would need to implement these functions only if they had mount time options, such as selinux has context= or fscontext=. If the LSM has no mount time options they could simply not implement and let the dummy ops take care of things. An LSM other than SELinux would need to define new option numbers in security.h and any FS which decides to own there own security options would need to be patched to use this new interface for every possible LSM. This is because it was stated to me very clearly that LSM's should not attempt to understand FS mount data and the burdon to understand security should be in the FS which owns the options. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2007-11-30 21:00:35 +03:00
{
return security_ops->sb_set_mnt_opts(sb, opts);
Security: add get, set, and cloning of superblock security information Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow filesystems to directly own and control all of their mount options if they so choose. This interface deals only with option identifiers and strings so it should generic enough for any LSM which may come in the future. Filesystems which pass text mount data around in the kernel (almost all of them) need not currently make use of this interface when dealing with SELinux since it will still parse those strings as it always has. I assume future LSM's would do the same. NFS is the primary FS which does not use text mount data and thus must make use of this interface. An LSM would need to implement these functions only if they had mount time options, such as selinux has context= or fscontext=. If the LSM has no mount time options they could simply not implement and let the dummy ops take care of things. An LSM other than SELinux would need to define new option numbers in security.h and any FS which decides to own there own security options would need to be patched to use this new interface for every possible LSM. This is because it was stated to me very clearly that LSM's should not attempt to understand FS mount data and the burdon to understand security should be in the FS which owns the options. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2007-11-30 21:00:35 +03:00
}
EXPORT_SYMBOL(security_sb_set_mnt_opts);
Security: add get, set, and cloning of superblock security information Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow filesystems to directly own and control all of their mount options if they so choose. This interface deals only with option identifiers and strings so it should generic enough for any LSM which may come in the future. Filesystems which pass text mount data around in the kernel (almost all of them) need not currently make use of this interface when dealing with SELinux since it will still parse those strings as it always has. I assume future LSM's would do the same. NFS is the primary FS which does not use text mount data and thus must make use of this interface. An LSM would need to implement these functions only if they had mount time options, such as selinux has context= or fscontext=. If the LSM has no mount time options they could simply not implement and let the dummy ops take care of things. An LSM other than SELinux would need to define new option numbers in security.h and any FS which decides to own there own security options would need to be patched to use this new interface for every possible LSM. This is because it was stated to me very clearly that LSM's should not attempt to understand FS mount data and the burdon to understand security should be in the FS which owns the options. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2007-11-30 21:00:35 +03:00
void security_sb_clone_mnt_opts(const struct super_block *oldsb,
struct super_block *newsb)
{
security_ops->sb_clone_mnt_opts(oldsb, newsb);
}
EXPORT_SYMBOL(security_sb_clone_mnt_opts);
int security_sb_parse_opts_str(char *options, struct security_mnt_opts *opts)
{
return security_ops->sb_parse_opts_str(options, opts);
}
EXPORT_SYMBOL(security_sb_parse_opts_str);
Security: add get, set, and cloning of superblock security information Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow filesystems to directly own and control all of their mount options if they so choose. This interface deals only with option identifiers and strings so it should generic enough for any LSM which may come in the future. Filesystems which pass text mount data around in the kernel (almost all of them) need not currently make use of this interface when dealing with SELinux since it will still parse those strings as it always has. I assume future LSM's would do the same. NFS is the primary FS which does not use text mount data and thus must make use of this interface. An LSM would need to implement these functions only if they had mount time options, such as selinux has context= or fscontext=. If the LSM has no mount time options they could simply not implement and let the dummy ops take care of things. An LSM other than SELinux would need to define new option numbers in security.h and any FS which decides to own there own security options would need to be patched to use this new interface for every possible LSM. This is because it was stated to me very clearly that LSM's should not attempt to understand FS mount data and the burdon to understand security should be in the FS which owns the options. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
2007-11-30 21:00:35 +03:00
int security_inode_alloc(struct inode *inode)
{
inode->i_security = NULL;
return security_ops->inode_alloc_security(inode);
}
void security_inode_free(struct inode *inode)
{
security_ops->inode_free_security(inode);
}
int security_inode_init_security(struct inode *inode, struct inode *dir,
char **name, void **value, size_t *len)
{
if (unlikely(IS_PRIVATE(inode)))
return -EOPNOTSUPP;
return security_ops->inode_init_security(inode, dir, name, value, len);
}
EXPORT_SYMBOL(security_inode_init_security);
int security_inode_create(struct inode *dir, struct dentry *dentry, int mode)
{
if (unlikely(IS_PRIVATE(dir)))
return 0;
return security_ops->inode_create(dir, dentry, mode);
}
int security_inode_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *new_dentry)
{
if (unlikely(IS_PRIVATE(old_dentry->d_inode)))
return 0;
return security_ops->inode_link(old_dentry, dir, new_dentry);
}
int security_inode_unlink(struct inode *dir, struct dentry *dentry)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_unlink(dir, dentry);
}
int security_inode_symlink(struct inode *dir, struct dentry *dentry,
const char *old_name)
{
if (unlikely(IS_PRIVATE(dir)))
return 0;
return security_ops->inode_symlink(dir, dentry, old_name);
}
int security_inode_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
if (unlikely(IS_PRIVATE(dir)))
return 0;
return security_ops->inode_mkdir(dir, dentry, mode);
}
int security_inode_rmdir(struct inode *dir, struct dentry *dentry)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_rmdir(dir, dentry);
}
int security_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
if (unlikely(IS_PRIVATE(dir)))
return 0;
return security_ops->inode_mknod(dir, dentry, mode, dev);
}
int security_inode_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
if (unlikely(IS_PRIVATE(old_dentry->d_inode) ||
(new_dentry->d_inode && IS_PRIVATE(new_dentry->d_inode))))
return 0;
return security_ops->inode_rename(old_dir, old_dentry,
new_dir, new_dentry);
}
int security_inode_readlink(struct dentry *dentry)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_readlink(dentry);
}
int security_inode_follow_link(struct dentry *dentry, struct nameidata *nd)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_follow_link(dentry, nd);
}
int security_inode_permission(struct inode *inode, int mask, struct nameidata *nd)
{
if (unlikely(IS_PRIVATE(inode)))
return 0;
return security_ops->inode_permission(inode, mask, nd);
}
int security_inode_setattr(struct dentry *dentry, struct iattr *attr)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_setattr(dentry, attr);
}
int security_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_getattr(mnt, dentry);
}
void security_inode_delete(struct inode *inode)
{
if (unlikely(IS_PRIVATE(inode)))
return;
security_ops->inode_delete(inode);
}
int security_inode_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_setxattr(dentry, name, value, size, flags);
}
void security_inode_post_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return;
security_ops->inode_post_setxattr(dentry, name, value, size, flags);
}
int security_inode_getxattr(struct dentry *dentry, const char *name)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_getxattr(dentry, name);
}
int security_inode_listxattr(struct dentry *dentry)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_listxattr(dentry);
}
int security_inode_removexattr(struct dentry *dentry, const char *name)
{
if (unlikely(IS_PRIVATE(dentry->d_inode)))
return 0;
return security_ops->inode_removexattr(dentry, name);
}
Implement file posix capabilities Implement file posix capabilities. This allows programs to be given a subset of root's powers regardless of who runs them, without having to use setuid and giving the binary all of root's powers. This version works with Kaigai Kohei's userspace tools, found at http://www.kaigai.gr.jp/index.php. For more information on how to use this patch, Chris Friedhoff has posted a nice page at http://www.friedhoff.org/fscaps.html. Changelog: Nov 27: Incorporate fixes from Andrew Morton (security-introduce-file-caps-tweaks and security-introduce-file-caps-warning-fix) Fix Kconfig dependency. Fix change signaling behavior when file caps are not compiled in. Nov 13: Integrate comments from Alexey: Remove CONFIG_ ifdef from capability.h, and use %zd for printing a size_t. Nov 13: Fix endianness warnings by sparse as suggested by Alexey Dobriyan. Nov 09: Address warnings of unused variables at cap_bprm_set_security when file capabilities are disabled, and simultaneously clean up the code a little, by pulling the new code into a helper function. Nov 08: For pointers to required userspace tools and how to use them, see http://www.friedhoff.org/fscaps.html. Nov 07: Fix the calculation of the highest bit checked in check_cap_sanity(). Nov 07: Allow file caps to be enabled without CONFIG_SECURITY, since capabilities are the default. Hook cap_task_setscheduler when !CONFIG_SECURITY. Move capable(TASK_KILL) to end of cap_task_kill to reduce audit messages. Nov 05: Add secondary calls in selinux/hooks.c to task_setioprio and task_setscheduler so that selinux and capabilities with file cap support can be stacked. Sep 05: As Seth Arnold points out, uid checks are out of place for capability code. Sep 01: Define task_setscheduler, task_setioprio, cap_task_kill, and task_setnice to make sure a user cannot affect a process in which they called a program with some fscaps. One remaining question is the note under task_setscheduler: are we ok with CAP_SYS_NICE being sufficient to confine a process to a cpuset? It is a semantic change, as without fsccaps, attach_task doesn't allow CAP_SYS_NICE to override the uid equivalence check. But since it uses security_task_setscheduler, which elsewhere is used where CAP_SYS_NICE can be used to override the uid equivalence check, fixing it might be tough. task_setscheduler note: this also controls cpuset:attach_task. Are we ok with CAP_SYS_NICE being used to confine to a cpuset? task_setioprio task_setnice sys_setpriority uses this (through set_one_prio) for another process. Need same checks as setrlimit Aug 21: Updated secureexec implementation to reflect the fact that euid and uid might be the same and nonzero, but the process might still have elevated caps. Aug 15: Handle endianness of xattrs. Enforce capability version match between kernel and disk. Enforce that no bits beyond the known max capability are set, else return -EPERM. With this extra processing, it may be worth reconsidering doing all the work at bprm_set_security rather than d_instantiate. Aug 10: Always call getxattr at bprm_set_security, rather than caching it at d_instantiate. [morgan@kernel.org: file-caps clean up for linux/capability.h] [bunk@kernel.org: unexport cap_inode_killpriv] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Andrew Morgan <morgan@kernel.org> Signed-off-by: Andrew Morgan <morgan@kernel.org> Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 10:31:36 +04:00
int security_inode_need_killpriv(struct dentry *dentry)
{
return security_ops->inode_need_killpriv(dentry);
}
int security_inode_killpriv(struct dentry *dentry)
{
return security_ops->inode_killpriv(dentry);
}
int security_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
{
if (unlikely(IS_PRIVATE(inode)))
return 0;
return security_ops->inode_getsecurity(inode, name, buffer, alloc);
}
int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags)
{
if (unlikely(IS_PRIVATE(inode)))
return 0;
return security_ops->inode_setsecurity(inode, name, value, size, flags);
}
int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
{
if (unlikely(IS_PRIVATE(inode)))
return 0;
return security_ops->inode_listsecurity(inode, buffer, buffer_size);
}
void security_inode_getsecid(const struct inode *inode, u32 *secid)
{
security_ops->inode_getsecid(inode, secid);
}
int security_file_permission(struct file *file, int mask)
{
return security_ops->file_permission(file, mask);
}
int security_file_alloc(struct file *file)
{
return security_ops->file_alloc_security(file);
}
void security_file_free(struct file *file)
{
security_ops->file_free_security(file);
}
int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return security_ops->file_ioctl(file, cmd, arg);
}
int security_file_mmap(struct file *file, unsigned long reqprot,
unsigned long prot, unsigned long flags,
unsigned long addr, unsigned long addr_only)
{
return security_ops->file_mmap(file, reqprot, prot, flags, addr, addr_only);
}
int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
unsigned long prot)
{
return security_ops->file_mprotect(vma, reqprot, prot);
}
int security_file_lock(struct file *file, unsigned int cmd)
{
return security_ops->file_lock(file, cmd);
}
int security_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
{
return security_ops->file_fcntl(file, cmd, arg);
}
int security_file_set_fowner(struct file *file)
{
return security_ops->file_set_fowner(file);
}
int security_file_send_sigiotask(struct task_struct *tsk,
struct fown_struct *fown, int sig)
{
return security_ops->file_send_sigiotask(tsk, fown, sig);
}
int security_file_receive(struct file *file)
{
return security_ops->file_receive(file);
}
int security_dentry_open(struct file *file)
{
return security_ops->dentry_open(file);
}
int security_task_create(unsigned long clone_flags)
{
return security_ops->task_create(clone_flags);
}
int security_task_alloc(struct task_struct *p)
{
return security_ops->task_alloc_security(p);
}
void security_task_free(struct task_struct *p)
{
security_ops->task_free_security(p);
}
int security_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
{
return security_ops->task_setuid(id0, id1, id2, flags);
}
int security_task_post_setuid(uid_t old_ruid, uid_t old_euid,
uid_t old_suid, int flags)
{
return security_ops->task_post_setuid(old_ruid, old_euid, old_suid, flags);
}
int security_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
{
return security_ops->task_setgid(id0, id1, id2, flags);
}
int security_task_setpgid(struct task_struct *p, pid_t pgid)
{
return security_ops->task_setpgid(p, pgid);
}
int security_task_getpgid(struct task_struct *p)
{
return security_ops->task_getpgid(p);
}
int security_task_getsid(struct task_struct *p)
{
return security_ops->task_getsid(p);
}
void security_task_getsecid(struct task_struct *p, u32 *secid)
{
security_ops->task_getsecid(p, secid);
}
EXPORT_SYMBOL(security_task_getsecid);
int security_task_setgroups(struct group_info *group_info)
{
return security_ops->task_setgroups(group_info);
}
int security_task_setnice(struct task_struct *p, int nice)
{
return security_ops->task_setnice(p, nice);
}
int security_task_setioprio(struct task_struct *p, int ioprio)
{
return security_ops->task_setioprio(p, ioprio);
}
int security_task_getioprio(struct task_struct *p)
{
return security_ops->task_getioprio(p);
}
int security_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
return security_ops->task_setrlimit(resource, new_rlim);
}
int security_task_setscheduler(struct task_struct *p,
int policy, struct sched_param *lp)
{
return security_ops->task_setscheduler(p, policy, lp);
}
int security_task_getscheduler(struct task_struct *p)
{
return security_ops->task_getscheduler(p);
}
int security_task_movememory(struct task_struct *p)
{
return security_ops->task_movememory(p);
}
int security_task_kill(struct task_struct *p, struct siginfo *info,
int sig, u32 secid)
{
return security_ops->task_kill(p, info, sig, secid);
}
int security_task_wait(struct task_struct *p)
{
return security_ops->task_wait(p);
}
int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
capabilities: implement per-process securebits Filesystem capability support makes it possible to do away with (set)uid-0 based privilege and use capabilities instead. That is, with filesystem support for capabilities but without this present patch, it is (conceptually) possible to manage a system with capabilities alone and never need to obtain privilege via (set)uid-0. Of course, conceptually isn't quite the same as currently possible since few user applications, certainly not enough to run a viable system, are currently prepared to leverage capabilities to exercise privilege. Further, many applications exist that may never get upgraded in this way, and the kernel will continue to want to support their setuid-0 base privilege needs. Where pure-capability applications evolve and replace setuid-0 binaries, it is desirable that there be a mechanisms by which they can contain their privilege. In addition to leveraging the per-process bounding and inheritable sets, this should include suppressing the privilege of the uid-0 superuser from the process' tree of children. The feature added by this patch can be leveraged to suppress the privilege associated with (set)uid-0. This suppression requires CAP_SETPCAP to initiate, and only immediately affects the 'current' process (it is inherited through fork()/exec()). This reimplementation differs significantly from the historical support for securebits which was system-wide, unwieldy and which has ultimately withered to a dead relic in the source of the modern kernel. With this patch applied a process, that is capable(CAP_SETPCAP), can now drop all legacy privilege (through uid=0) for itself and all subsequently fork()'d/exec()'d children with: prctl(PR_SET_SECUREBITS, 0x2f); This patch represents a no-op unless CONFIG_SECURITY_FILE_CAPABILITIES is enabled at configure time. [akpm@linux-foundation.org: fix uninitialised var warning] [serue@us.ibm.com: capabilities: use cap_task_prctl when !CONFIG_SECURITY] Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Reviewed-by: James Morris <jmorris@namei.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Paul Moore <paul.moore@hp.com> Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 13:13:40 +04:00
unsigned long arg4, unsigned long arg5, long *rc_p)
{
capabilities: implement per-process securebits Filesystem capability support makes it possible to do away with (set)uid-0 based privilege and use capabilities instead. That is, with filesystem support for capabilities but without this present patch, it is (conceptually) possible to manage a system with capabilities alone and never need to obtain privilege via (set)uid-0. Of course, conceptually isn't quite the same as currently possible since few user applications, certainly not enough to run a viable system, are currently prepared to leverage capabilities to exercise privilege. Further, many applications exist that may never get upgraded in this way, and the kernel will continue to want to support their setuid-0 base privilege needs. Where pure-capability applications evolve and replace setuid-0 binaries, it is desirable that there be a mechanisms by which they can contain their privilege. In addition to leveraging the per-process bounding and inheritable sets, this should include suppressing the privilege of the uid-0 superuser from the process' tree of children. The feature added by this patch can be leveraged to suppress the privilege associated with (set)uid-0. This suppression requires CAP_SETPCAP to initiate, and only immediately affects the 'current' process (it is inherited through fork()/exec()). This reimplementation differs significantly from the historical support for securebits which was system-wide, unwieldy and which has ultimately withered to a dead relic in the source of the modern kernel. With this patch applied a process, that is capable(CAP_SETPCAP), can now drop all legacy privilege (through uid=0) for itself and all subsequently fork()'d/exec()'d children with: prctl(PR_SET_SECUREBITS, 0x2f); This patch represents a no-op unless CONFIG_SECURITY_FILE_CAPABILITIES is enabled at configure time. [akpm@linux-foundation.org: fix uninitialised var warning] [serue@us.ibm.com: capabilities: use cap_task_prctl when !CONFIG_SECURITY] Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Reviewed-by: James Morris <jmorris@namei.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Paul Moore <paul.moore@hp.com> Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 13:13:40 +04:00
return security_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p);
}
void security_task_reparent_to_init(struct task_struct *p)
{
security_ops->task_reparent_to_init(p);
}
void security_task_to_inode(struct task_struct *p, struct inode *inode)
{
security_ops->task_to_inode(p, inode);
}
int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
{
return security_ops->ipc_permission(ipcp, flag);
}
void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
security_ops->ipc_getsecid(ipcp, secid);
}
int security_msg_msg_alloc(struct msg_msg *msg)
{
return security_ops->msg_msg_alloc_security(msg);
}
void security_msg_msg_free(struct msg_msg *msg)
{
security_ops->msg_msg_free_security(msg);
}
int security_msg_queue_alloc(struct msg_queue *msq)
{
return security_ops->msg_queue_alloc_security(msq);
}
void security_msg_queue_free(struct msg_queue *msq)
{
security_ops->msg_queue_free_security(msq);
}
int security_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
return security_ops->msg_queue_associate(msq, msqflg);
}
int security_msg_queue_msgctl(struct msg_queue *msq, int cmd)
{
return security_ops->msg_queue_msgctl(msq, cmd);
}
int security_msg_queue_msgsnd(struct msg_queue *msq,
struct msg_msg *msg, int msqflg)
{
return security_ops->msg_queue_msgsnd(msq, msg, msqflg);
}
int security_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
struct task_struct *target, long type, int mode)
{
return security_ops->msg_queue_msgrcv(msq, msg, target, type, mode);
}
int security_shm_alloc(struct shmid_kernel *shp)
{
return security_ops->shm_alloc_security(shp);
}
void security_shm_free(struct shmid_kernel *shp)
{
security_ops->shm_free_security(shp);
}
int security_shm_associate(struct shmid_kernel *shp, int shmflg)
{
return security_ops->shm_associate(shp, shmflg);
}
int security_shm_shmctl(struct shmid_kernel *shp, int cmd)
{
return security_ops->shm_shmctl(shp, cmd);
}
int security_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, int shmflg)
{
return security_ops->shm_shmat(shp, shmaddr, shmflg);
}
int security_sem_alloc(struct sem_array *sma)
{
return security_ops->sem_alloc_security(sma);
}
void security_sem_free(struct sem_array *sma)
{
security_ops->sem_free_security(sma);
}
int security_sem_associate(struct sem_array *sma, int semflg)
{
return security_ops->sem_associate(sma, semflg);
}
int security_sem_semctl(struct sem_array *sma, int cmd)
{
return security_ops->sem_semctl(sma, cmd);
}
int security_sem_semop(struct sem_array *sma, struct sembuf *sops,
unsigned nsops, int alter)
{
return security_ops->sem_semop(sma, sops, nsops, alter);
}
void security_d_instantiate(struct dentry *dentry, struct inode *inode)
{
if (unlikely(inode && IS_PRIVATE(inode)))
return;
security_ops->d_instantiate(dentry, inode);
}
EXPORT_SYMBOL(security_d_instantiate);
int security_getprocattr(struct task_struct *p, char *name, char **value)
{
return security_ops->getprocattr(p, name, value);
}
int security_setprocattr(struct task_struct *p, char *name, void *value, size_t size)
{
return security_ops->setprocattr(p, name, value, size);
}
int security_netlink_send(struct sock *sk, struct sk_buff *skb)
{
return security_ops->netlink_send(sk, skb);
}
int security_netlink_recv(struct sk_buff *skb, int cap)
{
return security_ops->netlink_recv(skb, cap);
}
EXPORT_SYMBOL(security_netlink_recv);
int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
return security_ops->secid_to_secctx(secid, secdata, seclen);
}
EXPORT_SYMBOL(security_secid_to_secctx);
int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
{
return security_ops->secctx_to_secid(secdata, seclen, secid);
}
EXPORT_SYMBOL(security_secctx_to_secid);
void security_release_secctx(char *secdata, u32 seclen)
{
security_ops->release_secctx(secdata, seclen);
}
EXPORT_SYMBOL(security_release_secctx);
#ifdef CONFIG_SECURITY_NETWORK
int security_unix_stream_connect(struct socket *sock, struct socket *other,
struct sock *newsk)
{
return security_ops->unix_stream_connect(sock, other, newsk);
}
EXPORT_SYMBOL(security_unix_stream_connect);
int security_unix_may_send(struct socket *sock, struct socket *other)
{
return security_ops->unix_may_send(sock, other);
}
EXPORT_SYMBOL(security_unix_may_send);
int security_socket_create(int family, int type, int protocol, int kern)
{
return security_ops->socket_create(family, type, protocol, kern);
}
int security_socket_post_create(struct socket *sock, int family,
int type, int protocol, int kern)
{
return security_ops->socket_post_create(sock, family, type,
protocol, kern);
}
int security_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
{
return security_ops->socket_bind(sock, address, addrlen);
}
int security_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
return security_ops->socket_connect(sock, address, addrlen);
}
int security_socket_listen(struct socket *sock, int backlog)
{
return security_ops->socket_listen(sock, backlog);
}
int security_socket_accept(struct socket *sock, struct socket *newsock)
{
return security_ops->socket_accept(sock, newsock);
}
void security_socket_post_accept(struct socket *sock, struct socket *newsock)
{
security_ops->socket_post_accept(sock, newsock);
}
int security_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size)
{
return security_ops->socket_sendmsg(sock, msg, size);
}
int security_socket_recvmsg(struct socket *sock, struct msghdr *msg,
int size, int flags)
{
return security_ops->socket_recvmsg(sock, msg, size, flags);
}
int security_socket_getsockname(struct socket *sock)
{
return security_ops->socket_getsockname(sock);
}
int security_socket_getpeername(struct socket *sock)
{
return security_ops->socket_getpeername(sock);
}
int security_socket_getsockopt(struct socket *sock, int level, int optname)
{
return security_ops->socket_getsockopt(sock, level, optname);
}
int security_socket_setsockopt(struct socket *sock, int level, int optname)
{
return security_ops->socket_setsockopt(sock, level, optname);
}
int security_socket_shutdown(struct socket *sock, int how)
{
return security_ops->socket_shutdown(sock, how);
}
int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
return security_ops->socket_sock_rcv_skb(sk, skb);
}
EXPORT_SYMBOL(security_sock_rcv_skb);
int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
int __user *optlen, unsigned len)
{
return security_ops->socket_getpeersec_stream(sock, optval, optlen, len);
}
int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
{
return security_ops->socket_getpeersec_dgram(sock, skb, secid);
}
EXPORT_SYMBOL(security_socket_getpeersec_dgram);
int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
{
return security_ops->sk_alloc_security(sk, family, priority);
}
void security_sk_free(struct sock *sk)
{
security_ops->sk_free_security(sk);
}
void security_sk_clone(const struct sock *sk, struct sock *newsk)
{
security_ops->sk_clone_security(sk, newsk);
}
void security_sk_classify_flow(struct sock *sk, struct flowi *fl)
{
security_ops->sk_getsecid(sk, &fl->secid);
}
EXPORT_SYMBOL(security_sk_classify_flow);
void security_req_classify_flow(const struct request_sock *req, struct flowi *fl)
{
security_ops->req_classify_flow(req, fl);
}
EXPORT_SYMBOL(security_req_classify_flow);
void security_sock_graft(struct sock *sk, struct socket *parent)
{
security_ops->sock_graft(sk, parent);
}
EXPORT_SYMBOL(security_sock_graft);
int security_inet_conn_request(struct sock *sk,
struct sk_buff *skb, struct request_sock *req)
{
return security_ops->inet_conn_request(sk, skb, req);
}
EXPORT_SYMBOL(security_inet_conn_request);
void security_inet_csk_clone(struct sock *newsk,
const struct request_sock *req)
{
security_ops->inet_csk_clone(newsk, req);
}
void security_inet_conn_established(struct sock *sk,
struct sk_buff *skb)
{
security_ops->inet_conn_established(sk, skb);
}
#endif /* CONFIG_SECURITY_NETWORK */
#ifdef CONFIG_SECURITY_NETWORK_XFRM
int security_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, struct xfrm_user_sec_ctx *sec_ctx)
{
return security_ops->xfrm_policy_alloc_security(ctxp, sec_ctx);
}
EXPORT_SYMBOL(security_xfrm_policy_alloc);
int security_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
struct xfrm_sec_ctx **new_ctxp)
{
return security_ops->xfrm_policy_clone_security(old_ctx, new_ctxp);
}
void security_xfrm_policy_free(struct xfrm_sec_ctx *ctx)
{
security_ops->xfrm_policy_free_security(ctx);
}
EXPORT_SYMBOL(security_xfrm_policy_free);
int security_xfrm_policy_delete(struct xfrm_sec_ctx *ctx)
{
return security_ops->xfrm_policy_delete_security(ctx);
}
int security_xfrm_state_alloc(struct xfrm_state *x, struct xfrm_user_sec_ctx *sec_ctx)
{
return security_ops->xfrm_state_alloc_security(x, sec_ctx, 0);
}
EXPORT_SYMBOL(security_xfrm_state_alloc);
int security_xfrm_state_alloc_acquire(struct xfrm_state *x,
struct xfrm_sec_ctx *polsec, u32 secid)
{
if (!polsec)
return 0;
/*
* We want the context to be taken from secid which is usually
* from the sock.
*/
return security_ops->xfrm_state_alloc_security(x, NULL, secid);
}
int security_xfrm_state_delete(struct xfrm_state *x)
{
return security_ops->xfrm_state_delete_security(x);
}
EXPORT_SYMBOL(security_xfrm_state_delete);
void security_xfrm_state_free(struct xfrm_state *x)
{
security_ops->xfrm_state_free_security(x);
}
int security_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir)
{
return security_ops->xfrm_policy_lookup(ctx, fl_secid, dir);
}
int security_xfrm_state_pol_flow_match(struct xfrm_state *x,
struct xfrm_policy *xp, struct flowi *fl)
{
return security_ops->xfrm_state_pol_flow_match(x, xp, fl);
}
int security_xfrm_decode_session(struct sk_buff *skb, u32 *secid)
{
return security_ops->xfrm_decode_session(skb, secid, 1);
}
void security_skb_classify_flow(struct sk_buff *skb, struct flowi *fl)
{
int rc = security_ops->xfrm_decode_session(skb, &fl->secid, 0);
BUG_ON(rc);
}
EXPORT_SYMBOL(security_skb_classify_flow);
#endif /* CONFIG_SECURITY_NETWORK_XFRM */
#ifdef CONFIG_KEYS
int security_key_alloc(struct key *key, struct task_struct *tsk, unsigned long flags)
{
return security_ops->key_alloc(key, tsk, flags);
}
void security_key_free(struct key *key)
{
security_ops->key_free(key);
}
int security_key_permission(key_ref_t key_ref,
struct task_struct *context, key_perm_t perm)
{
return security_ops->key_permission(key_ref, context, perm);
}
int security_key_getsecurity(struct key *key, char **_buffer)
{
return security_ops->key_getsecurity(key, _buffer);
}
#endif /* CONFIG_KEYS */
#ifdef CONFIG_AUDIT
int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule)
{
return security_ops->audit_rule_init(field, op, rulestr, lsmrule);
}
int security_audit_rule_known(struct audit_krule *krule)
{
return security_ops->audit_rule_known(krule);
}
void security_audit_rule_free(void *lsmrule)
{
security_ops->audit_rule_free(lsmrule);
}
int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule,
struct audit_context *actx)
{
return security_ops->audit_rule_match(secid, field, op, lsmrule, actx);
}
#endif /* CONFIG_AUDIT */