Changeset 2bb8648 in mainline for generic/src/security/cap.c

Timestamp:

2006-05-07T15:21:11Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

31282f9

Parents:

ecf3722

Message:

Add SYS_CAP_GRANT and SYS_CAP_REVOKE syscalls.
Move SYS_PREEMPT_CONTROL to ddi.c.
Add some comments and fix some small issues.

File:

• generic/src/security/cap.c (modified) (2 diffs)

generic/src/security/cap.c

@@ -37 +37 @@
 #include <proc/task.h>
 #include <synch/spinlock.h>
+#include <syscall/sysarg64.h>
+#include <syscall/copy.h>
 #include <arch.h>
 #include <typedefs.h>
+#include <errno.h>
 
 /** Set capabilities.
@@ -78 +81 @@
         return caps;
 }
+
+/** Grant capabilities to a task.
+ *
+ * The calling task must have the CAP_CAP capability.
+ *
+ * @param uspace_taskid_arg Userspace structure holding destination task ID.
+ * @param caps Capabilities to grant.
+ *
+ * @return Zero on success or an error code from @ref errno.h.
+ */
+__native sys_cap_grant(sysarg64_t *uspace_taskid_arg, cap_t caps)
+{
+        sysarg64_t taskid_arg;
+        task_t *t;
+        ipl_t ipl;
+        int rc;
+        
+        if (!(cap_get(TASK) & CAP_CAP))
+                return (__native) EPERM;
+        
+        rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
+        if (rc != 0)
+                return (__native) rc;
+                
+        ipl = interrupts_disable();
+        spinlock_lock(&tasks_lock);
+        t = task_find_by_id((task_id_t) taskid_arg.value);
+        if (!t) {
+                spinlock_unlock(&tasks_lock);
+                interrupts_restore(ipl);
+                return (__native) ENOENT;
+        }
+        spinlock_unlock(&tasks_lock);
+        
+        cap_set(t, cap_get(t) | caps);
+        
+        interrupts_restore(ipl);        
+        return 0;
+}
+
+/** Revoke capabilities from a task.
+ *
+ * The calling task must have the CAP_CAP capability or the caller must
+ * attempt to revoke capabilities from itself.
+ *
+ * @param uspace_taskid_arg Userspace structure holding destination task ID.
+ * @param caps Capabilities to revoke.
+ *
+ * @return Zero on success or an error code from @ref errno.h.
+ */
+__native sys_cap_revoke(sysarg64_t *uspace_taskid_arg, cap_t caps)
+{
+        sysarg64_t taskid_arg;
+        task_t *t;
+        ipl_t ipl;
+        int rc;
+        
+        rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
+        if (rc != 0)
+                return (__native) rc;
+
+        ipl = interrupts_disable();
+        spinlock_lock(&tasks_lock);     
+        t = task_find_by_id((task_id_t) taskid_arg.value);
+        if (!t) {
+                spinlock_unlock(&tasks_lock);
+                interrupts_restore(ipl);
+                return (__native) ENOENT;
+        }
+        spinlock_unlock(&tasks_lock);
+
+        /*
+         * Revoking capabilities is different from granting them in that
+         * a task can revoke capabilities from itself even if it
+         * doesn't have CAP_CAP.
+         */
+        if (!(cap_get(TASK) & CAP_CAP) || !(t == TASK)) {
+                interrupts_restore(ipl);
+                return (__native) EPERM;
+        }
+
+        cap_set(t, cap_get(t) & ~caps);
+        
+        interrupts_restore(ipl);
+        return 0;
+}