1 | /* The kernel call implemented in this file:
|
---|
2 | * m_type: SYS_PRIVCTL
|
---|
3 | *
|
---|
4 | * The parameters for this kernel call are:
|
---|
5 | * m1_i1: PR_PROC_NR (process number of caller)
|
---|
6 | */
|
---|
7 |
|
---|
8 | #include "../system.h"
|
---|
9 | #include "../ipc.h"
|
---|
10 | #include <signal.h>
|
---|
11 |
|
---|
12 | #if USE_PRIVCTL
|
---|
13 |
|
---|
14 | #define FILLED_MASK (~0)
|
---|
15 |
|
---|
16 | /*===========================================================================*
|
---|
17 | * do_privctl *
|
---|
18 | *===========================================================================*/
|
---|
19 | PUBLIC int do_privctl(m_ptr)
|
---|
20 | message *m_ptr; /* pointer to request message */
|
---|
21 | {
|
---|
22 | /* Handle sys_privctl(). Update a process' privileges. If the process is not
|
---|
23 | * yet a system process, make sure it gets its own privilege structure.
|
---|
24 | */
|
---|
25 | register struct proc *caller_ptr;
|
---|
26 | register struct proc *rp;
|
---|
27 | register struct priv *sp;
|
---|
28 | int proc_nr;
|
---|
29 | int priv_id;
|
---|
30 | int old_flags;
|
---|
31 | int i;
|
---|
32 |
|
---|
33 | /* Check whether caller is allowed to make this call. Privileged proceses
|
---|
34 | * can only update the privileges of processes that are inhibited from
|
---|
35 | * running by the NO_PRIV flag. This flag is set when a privileged process
|
---|
36 | * forks.
|
---|
37 | */
|
---|
38 | caller_ptr = proc_addr(m_ptr->m_source);
|
---|
39 | if (! (priv(caller_ptr)->s_flags & SYS_PROC)) return(EPERM);
|
---|
40 | proc_nr = m_ptr->PR_PROC_NR;
|
---|
41 | if (! isokprocn(proc_nr)) return(EINVAL);
|
---|
42 | rp = proc_addr(proc_nr);
|
---|
43 | if (! (rp->p_rts_flags & NO_PRIV)) return(EPERM);
|
---|
44 |
|
---|
45 | /* Make sure this process has its own privileges structure. This may fail,
|
---|
46 | * since there are only a limited number of system processes. Then copy the
|
---|
47 | * privileges from the caller and restore some defaults.
|
---|
48 | */
|
---|
49 | if ((i=get_priv(rp, SYS_PROC)) != OK) return(i);
|
---|
50 | priv_id = priv(rp)->s_id; /* backup privilege id */
|
---|
51 | *priv(rp) = *priv(caller_ptr); /* copy from caller */
|
---|
52 | priv(rp)->s_id = priv_id; /* restore privilege id */
|
---|
53 | priv(rp)->s_proc_nr = proc_nr; /* reassociate process nr */
|
---|
54 |
|
---|
55 | for (i=0; i< BITMAP_CHUNKS(NR_SYS_PROCS); i++) /* remove pending: */
|
---|
56 | priv(rp)->s_notify_pending.chunk[i] = 0; /* - notifications */
|
---|
57 | priv(rp)->s_int_pending = 0; /* - interrupts */
|
---|
58 | sigemptyset(&priv(rp)->s_sig_pending); /* - signals */
|
---|
59 |
|
---|
60 | /* Now update the process' privileges as requested. */
|
---|
61 | rp->p_priv->s_trap_mask = FILLED_MASK;
|
---|
62 | for (i=0; i<BITMAP_CHUNKS(NR_SYS_PROCS); i++) {
|
---|
63 | rp->p_priv->s_ipc_to.chunk[i] = FILLED_MASK;
|
---|
64 | }
|
---|
65 | unset_sys_bit(rp->p_priv->s_ipc_to, USER_PRIV_ID);
|
---|
66 |
|
---|
67 | /* All process that this process can send to must be able to reply.
|
---|
68 | * Therefore, their send masks should be updated as well.
|
---|
69 | */
|
---|
70 | for (i=0; i<NR_SYS_PROCS; i++) {
|
---|
71 | if (get_sys_bit(rp->p_priv->s_ipc_to, i)) {
|
---|
72 | set_sys_bit(priv_addr(i)->s_ipc_to, priv_id(rp));
|
---|
73 | }
|
---|
74 | }
|
---|
75 |
|
---|
76 | /* Done. Privileges have been set. Allow process to run again. */
|
---|
77 | old_flags = rp->p_rts_flags; /* save value of the flags */
|
---|
78 | rp->p_rts_flags &= ~NO_PRIV;
|
---|
79 | if (old_flags != 0 && rp->p_rts_flags == 0) lock_enqueue(rp);
|
---|
80 | return(OK);
|
---|
81 | }
|
---|
82 |
|
---|
83 | #endif /* USE_PRIVCTL */
|
---|
84 |
|
---|