Messages in this thread Patch in this message | | | Date | Mon, 30 Aug 2004 09:38:23 -0500 | From | Michael Halcrow <> | Subject | [PATCH] BSD Secure Levels LSM (2/3) |
| |
BSD Secure Levels LSM. This adds settime hooks necessary to support the BSD Secure Levels model.
Signed-off-by: Michael A. Halcrow <mike@halcrow.us>--- linux-2.6.8-rc3/arch/mips/kernel/sysirix.c 2004-08-09 16:15:39.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/arch/mips/kernel/sysirix.c 2004-08-09 16:16:33.000000000 -0500 @@ -614,8 +614,14 @@ asmlinkage int irix_stime(int value) { - if (!capable(CAP_SYS_TIME)) - return -EPERM; + int err; + struct timespec tv; + + tv.tv_sec = value; + tv.tv_nsec = 0; + err = security_settime(&tv, NULL); + if (err) + return err; write_seqlock_irq(&xtime_lock); xtime.tv_sec = value; --- linux-2.6.8-rc3/arch/ppc64/kernel/time.c 2004-08-09 16:15:42.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/arch/ppc64/kernel/time.c 2004-08-09 16:16:35.000000000 -0500 @@ -435,9 +435,7 @@ { int value; struct timespec myTimeval; - - if (!capable(CAP_SYS_TIME)) - return -EPERM; + int err; if (get_user(value, tptr)) return -EFAULT; @@ -445,6 +443,10 @@ myTimeval.tv_sec = value; myTimeval.tv_nsec = 0; + err = security_settime(&myTimeval, NULL); + if (err) + return err; + do_settimeofday(&myTimeval); return 0; @@ -460,9 +462,7 @@ { long value; struct timespec myTimeval; - - if (!capable(CAP_SYS_TIME)) - return -EPERM; + int err; if (get_user(value, tptr)) return -EFAULT; @@ -470,6 +470,10 @@ myTimeval.tv_sec = value; myTimeval.tv_nsec = 0; + err = security_settime(&myTimeval, NULL); + if (err) + return err; + do_settimeofday(&myTimeval); return 0; --- linux-2.6.8-rc3/include/linux/security.h 2004-08-09 16:16:08.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/include/linux/security.h 2004-08-09 16:17:00.000000000 -0500 @@ -39,6 +39,7 @@ * as the default capabilities functions */ extern int cap_capable (struct task_struct *tsk, int cap); +extern int cap_settime (struct timespec *ts, struct timezone *tz); extern int cap_ptrace (struct task_struct *parent, struct task_struct *child); extern int cap_capget (struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted); extern int cap_capset_check (struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted); @@ -999,6 +1000,12 @@ * See the syslog(2) manual page for an explanation of the @type values. * @type contains the type of action. * Return 0 if permission is granted. + * @settime: + * Check permission to change the system time. + * struct timespec and timezone are defined in include/linux/time.h + * @ts contains new time + * @tz contains new timezone + * Return 0 if permission is granted. * @vm_enough_memory: * Check permissions for allocating a new virtual mapping. * @pages contains the number of pages. @@ -1034,6 +1041,7 @@ int (*quotactl) (int cmds, int type, int id, struct super_block * sb); int (*quota_on) (struct file * f); int (*syslog) (int type); + int (*settime) (struct timespec *ts, struct timezone *tz); int (*vm_enough_memory) (long pages); int (*bprm_alloc_security) (struct linux_binprm * bprm); @@ -1289,6 +1297,12 @@ return security_ops->syslog(type); } +static inline int security_settime(struct timespec *ts, struct timezone *tz) +{ + return security_ops->settime(ts, tz); +} + + static inline int security_vm_enough_memory(long pages) { return security_ops->vm_enough_memory(pages); @@ -1961,6 +1975,11 @@ return cap_syslog(type); } +static inline int security_settime(struct timespec *ts, struct timezone *tz) +{ + return cap_settime(ts, tz); +} + static inline int security_vm_enough_memory(long pages) { return cap_vm_enough_memory(pages); --- linux-2.6.8-rc3/kernel/time.c 2004-06-16 00:19:01.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/kernel/time.c 2004-08-09 08:05:02.000000000 -0500 @@ -28,6 +28,7 @@ #include <linux/timex.h> #include <linux/errno.h> #include <linux/smp_lock.h> +#include <linux/security.h> #include <asm/uaccess.h> #include <asm/unistd.h> @@ -74,13 +75,17 @@ asmlinkage long sys_stime(time_t __user *tptr) { struct timespec tv; + int err; - if (!capable(CAP_SYS_TIME)) - return -EPERM; if (get_user(tv.tv_sec, tptr)) return -EFAULT; tv.tv_nsec = 0; + + err = security_settime(&tv, NULL); + if (err) + return err; + do_settimeofday(&tv); return 0; } @@ -142,10 +147,12 @@ int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) { static int firsttime = 1; + int error = 0; + + error = security_settime(tv, tz); + if (error) + return error; - if (!capable(CAP_SYS_TIME)) - return -EPERM; - if (tz) { /* SMP safe, global irq locking makes it work. */ sys_tz = *tz; --- linux-2.6.8-rc3/security/capability.c 2004-06-16 00:19:13.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/security/capability.c 2004-08-09 08:03:30.000000000 -0500 @@ -30,6 +30,7 @@ .capset_check = cap_capset_check, .capset_set = cap_capset_set, .capable = cap_capable, + .settime = cap_settime, .netlink_send = cap_netlink_send, .netlink_recv = cap_netlink_recv, --- linux-2.6.8-rc3/security/commoncap.c 2004-06-16 00:19:13.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/security/commoncap.c 2004-08-09 08:06:57.000000000 -0500 @@ -27,20 +27,25 @@ int cap_capable (struct task_struct *tsk, int cap) { /* Derived from include/linux/sched.h:capable. */ - if (cap_raised (tsk->cap_effective, cap)) + if (cap_raised(tsk->cap_effective, cap)) return 0; - else + return -EPERM; +} + +int cap_settime(struct timespec *ts, struct timezone *tz) +{ + if (!capable(CAP_SYS_TIME)) return -EPERM; + return 0; } int cap_ptrace (struct task_struct *parent, struct task_struct *child) { /* Derived from arch/i386/kernel/ptrace.c:sys_ptrace. */ if (!cap_issubset (child->cap_permitted, current->cap_permitted) && - !capable (CAP_SYS_PTRACE)) + !capable(CAP_SYS_PTRACE)) return -EPERM; - else - return 0; + return 0; } int cap_capget (struct task_struct *target, kernel_cap_t *effective, @@ -368,6 +373,7 @@ } EXPORT_SYMBOL(cap_capable); +EXPORT_SYMBOL(cap_settime); EXPORT_SYMBOL(cap_ptrace); EXPORT_SYMBOL(cap_capget); EXPORT_SYMBOL(cap_capset_check); --- linux-2.6.8-rc3/security/dummy.c 2004-08-09 16:16:09.000000000 -0500 +++ linux-2.6.8-rc3_seclvl/security/dummy.c 2004-08-09 16:17:05.000000000 -0500 @@ -104,6 +104,13 @@ return 0; } +static int dummy_settime (struct timeval *tv, struct timezone *tz) +{ + if (!capable(CAP_SYS_TIME)) + return -EPERM; + return 0; +} + /* * Check that a process has enough memory to allocate a new virtual * mapping. 0 means there is enough memory for the allocation to @@ -897,6 +904,7 @@ set_to_dummy_if_null(ops, quota_on); set_to_dummy_if_null(ops, sysctl); set_to_dummy_if_null(ops, syslog); + set_to_dummy_if_null(ops, settime); set_to_dummy_if_null(ops, vm_enough_memory); set_to_dummy_if_null(ops, bprm_alloc_security); set_to_dummy_if_null(ops, bprm_free_security); | |