From d720024e94de4e8b7f10ee83c532926f3ad5d708 Mon Sep 17 00:00:00 2001 From: Michael LeMay Date: Thu, 22 Jun 2006 14:47:17 -0700 Subject: [PATCH] selinux: add hooks for key subsystem Introduce SELinux hooks to support the access key retention subsystem within the kernel. Incorporate new flask headers from a modified version of the SELinux reference policy, with support for the new security class representing retained keys. Extend the "key_alloc" security hook with a task parameter representing the intended ownership context for the key being allocated. Attach security information to root's default keyrings within the SELinux initialization routine. Has passed David's testsuite. Signed-off-by: Michael LeMay Signed-off-by: David Howells Signed-off-by: James Morris Acked-by: Chris Wright Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 54adc9d31e92..524915dfda64 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4252,6 +4252,57 @@ static int selinux_setprocattr(struct task_struct *p, return size; } +#ifdef CONFIG_KEYS + +static int selinux_key_alloc(struct key *k, struct task_struct *tsk) +{ + struct task_security_struct *tsec = tsk->security; + struct key_security_struct *ksec; + + ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); + if (!ksec) + return -ENOMEM; + + ksec->obj = k; + ksec->sid = tsec->sid; + k->security = ksec; + + return 0; +} + +static void selinux_key_free(struct key *k) +{ + struct key_security_struct *ksec = k->security; + + k->security = NULL; + kfree(ksec); +} + +static int selinux_key_permission(key_ref_t key_ref, + struct task_struct *ctx, + key_perm_t perm) +{ + struct key *key; + struct task_security_struct *tsec; + struct key_security_struct *ksec; + + key = key_ref_to_ptr(key_ref); + + tsec = ctx->security; + ksec = key->security; + + /* if no specific permissions are requested, we skip the + permission check. No serious, additional covert channels + appear to be created. */ + if (perm == 0) + return 0; + + return avc_has_perm(tsec->sid, ksec->sid, + SECCLASS_KEY, perm, NULL); +} + +#endif + static struct security_operations selinux_ops = { .ptrace = selinux_ptrace, .capget = selinux_capget, @@ -4406,6 +4457,12 @@ static struct security_operations selinux_ops = { .xfrm_state_delete_security = selinux_xfrm_state_delete, .xfrm_policy_lookup = selinux_xfrm_policy_lookup, #endif + +#ifdef CONFIG_KEYS + .key_alloc = selinux_key_alloc, + .key_free = selinux_key_free, + .key_permission = selinux_key_permission, +#endif }; static __init int selinux_init(void) @@ -4441,6 +4498,13 @@ static __init int selinux_init(void) } else { printk(KERN_INFO "SELinux: Starting in permissive mode\n"); } + +#ifdef CONFIG_KEYS + /* Add security information to initial keyrings */ + security_key_alloc(&root_user_keyring, current); + security_key_alloc(&root_session_keyring, current); +#endif + return 0; } -- cgit v1.2.3 From 726c334223180e3c0197cc980a432681370d4baf Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 23 Jun 2006 02:02:58 -0700 Subject: [PATCH] VFS: Permit filesystem to perform statfs with a known root dentry Give the statfs superblock operation a dentry pointer rather than a superblock pointer. This complements the get_sb() patch. That reduced the significance of sb->s_root, allowing NFS to place a fake root there. However, NFS does require a dentry to use as a target for the statfs operation. This permits the root in the vfsmount to be used instead. linux/mount.h has been added where necessary to make allyesconfig build successfully. Interest has also been expressed for use with the FUSE and XFS filesystems. Signed-off-by: David Howells Acked-by: Al Viro Cc: Nathan Scott Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 524915dfda64..093efba4d9b6 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1903,13 +1903,13 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data) return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); } -static int selinux_sb_statfs(struct super_block *sb) +static int selinux_sb_statfs(struct dentry *dentry) { struct avc_audit_data ad; AVC_AUDIT_DATA_INIT(&ad,FS); - ad.u.fs.dentry = sb->s_root; - return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad); + ad.u.fs.dentry = dentry->d_sb->s_root; + return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); } static int selinux_mount(char * dev_name, -- cgit v1.2.3 From 03e68060636e05989ea94bcb671ab633948f328c Mon Sep 17 00:00:00 2001 From: James Morris Date: Fri, 23 Jun 2006 02:03:58 -0700 Subject: [PATCH] lsm: add task_setioprio hook Implement an LSM hook for setting a task's IO priority, similar to the hook for setting a tasks's nice value. A previous version of this LSM hook was included in an older version of multiadm by Jan Engelhardt, although I don't recall it being submitted upstream. Also included is the corresponding SELinux hook, which re-uses the setsched permission in the proccess class. Signed-off-by: James Morris Acked-by: Stephen Smalley Cc: Jan Engelhardt Cc: Chris Wright Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 093efba4d9b6..9dcf298921d4 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2645,6 +2645,11 @@ static int selinux_task_setnice(struct task_struct *p, int nice) return task_has_perm(current,p, PROCESS__SETSCHED); } +static int selinux_task_setioprio(struct task_struct *p, int ioprio) +{ + return task_has_perm(current, p, PROCESS__SETSCHED); +} + static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) { struct rlimit *old_rlim = current->signal->rlim + resource; @@ -4383,6 +4388,7 @@ static struct security_operations selinux_ops = { .task_getsid = selinux_task_getsid, .task_setgroups = selinux_task_setgroups, .task_setnice = selinux_task_setnice, + .task_setioprio = selinux_task_setioprio, .task_setrlimit = selinux_task_setrlimit, .task_setscheduler = selinux_task_setscheduler, .task_getscheduler = selinux_task_getscheduler, -- cgit v1.2.3 From 35601547baf92d984b6e59cf3583649da04baea5 Mon Sep 17 00:00:00 2001 From: David Quigley Date: Fri, 23 Jun 2006 02:04:01 -0700 Subject: [PATCH] SELinux: add task_movememory hook This patch adds new security hook, task_movememory, to be called when memory owened by a task is to be moved (e.g. when migrating pages to a this hook is identical to the setscheduler implementation, but a separate hook introduced to allow this check to be specialized in the future if necessary. Since the last posting, the hook has been renamed following feedback from Christoph Lameter. Signed-off-by: David Quigley Acked-by: Stephen Smalley Signed-off-by: James Morris Cc: Christoph Lameter Cc: Andi Kleen Acked-by: Chris Wright Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9dcf298921d4..79c16e31c884 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2679,6 +2679,11 @@ static int selinux_task_getscheduler(struct task_struct *p) return task_has_perm(current, p, PROCESS__GETSCHED); } +static int selinux_task_movememory(struct task_struct *p) +{ + return task_has_perm(current, p, PROCESS__SETSCHED); +} + static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig) { u32 perm; @@ -4392,6 +4397,7 @@ static struct security_operations selinux_ops = { .task_setrlimit = selinux_task_setrlimit, .task_setscheduler = selinux_task_setscheduler, .task_getscheduler = selinux_task_getscheduler, + .task_movememory = selinux_task_movememory, .task_kill = selinux_task_kill, .task_wait = selinux_task_wait, .task_prctl = selinux_task_prctl, -- cgit v1.2.3