1 /* The kernel call implemented in this file:
2 * m_type: SYS_PRIVCTL
3 *
4 * The parameters for this kernel call are:
5 * m_lsys_krn_sys_privctl.endpt (process endpoint of target)
6 * m_lsys_krn_sys_privctl.request (privilege control request)
7 * m_lsys_krn_sys_privctl.arg_ptr (pointer to request data)
8 * m.m_lsys_krn_sys_privctl.phys_start
9 * m.m_lsys_krn_sys_privctl.phys_len
10 */
11
12 #include "kernel/system.h"
13 #include <signal.h>
14 #include <string.h>
15 #include <minix/endpoint.h>
16
17 #if USE_PRIVCTL
18
19 #define PRIV_DEBUG 0
20
21 static int update_priv(struct proc *rp, struct priv *priv);
22
23 /*===========================================================================*
24 * do_privctl *
25 *===========================================================================*/
do_privctl(struct proc * caller,message * m_ptr)26 int do_privctl(struct proc * caller, message * m_ptr)
27 {
28 /* Handle sys_privctl(). Update a process' privileges. If the process is not
29 * yet a system process, make sure it gets its own privilege structure.
30 */
31 struct proc *rp;
32 proc_nr_t proc_nr;
33 sys_id_t priv_id;
34 sys_map_t map;
35 int ipc_to_m, kcalls;
36 int i, r;
37 struct io_range io_range;
38 struct minix_mem_range mem_range;
39 struct priv priv;
40 int irq;
41
42 /* Check whether caller is allowed to make this call. Privileged processes
43 * can only update the privileges of processes that are inhibited from
44 * running by the RTS_NO_PRIV flag. This flag is set when a privileged process
45 * forks.
46 */
47 if (! (priv(caller)->s_flags & SYS_PROC)) return(EPERM);
48 if(m_ptr->m_lsys_krn_sys_privctl.endpt == SELF) okendpt(caller->p_endpoint,
49 &proc_nr);
50 else if(!isokendpt(m_ptr->m_lsys_krn_sys_privctl.endpt, &proc_nr))
51 return(EINVAL);
52 rp = proc_addr(proc_nr);
53
54 switch(m_ptr->m_lsys_krn_sys_privctl.request)
55 {
56 case SYS_PRIV_ALLOW:
57 /* Allow process to run. Make sure its privilege structure has already
58 * been set.
59 */
60 if (!RTS_ISSET(rp, RTS_NO_PRIV) || priv(rp)->s_proc_nr == NONE) {
61 return(EPERM);
62 }
63 RTS_UNSET(rp, RTS_NO_PRIV);
64 return(OK);
65
66 case SYS_PRIV_YIELD:
67 /* Allow process to run and suspend the caller. */
68 if (!RTS_ISSET(rp, RTS_NO_PRIV) || priv(rp)->s_proc_nr == NONE) {
69 return(EPERM);
70 }
71 RTS_SET(caller, RTS_NO_PRIV);
72 RTS_UNSET(rp, RTS_NO_PRIV);
73 return(OK);
74
75 case SYS_PRIV_DISALLOW:
76 /* Disallow process from running. */
77 if (RTS_ISSET(rp, RTS_NO_PRIV)) return(EPERM);
78 RTS_SET(rp, RTS_NO_PRIV);
79 return(OK);
80
81 case SYS_PRIV_CLEAR_IPC_REFS:
82 /* Clear pending IPC for the process. */
83 clear_ipc_refs(rp, EDEADSRCDST);
84 return(OK);
85
86 case SYS_PRIV_SET_SYS:
87 /* Set a privilege structure of a blocked system process. */
88 if (! RTS_ISSET(rp, RTS_NO_PRIV)) return(EPERM);
89
90 /* Check whether a static or dynamic privilege id must be allocated. */
91 priv_id = NULL_PRIV_ID;
92 if (m_ptr->m_lsys_krn_sys_privctl.arg_ptr)
93 {
94 /* Copy privilege structure from caller */
95 if((r=data_copy(caller->p_endpoint,
96 m_ptr->m_lsys_krn_sys_privctl.arg_ptr, KERNEL,
97 (vir_bytes) &priv, sizeof(priv))) != OK)
98 return r;
99
100 /* See if the caller wants to assign a static privilege id. */
101 if(!(priv.s_flags & DYN_PRIV_ID)) {
102 priv_id = priv.s_id;
103 }
104 }
105
106 /* Make sure this process has its own privileges structure. This may
107 * fail, since there are only a limited number of system processes.
108 * Then copy privileges from the caller and restore some defaults.
109 */
110 if ((i=get_priv(rp, priv_id)) != OK)
111 {
112 printf("do_privctl: unable to allocate priv_id %d: %d\n",
113 priv_id, i);
114 return(i);
115 }
116 priv_id = priv(rp)->s_id; /* backup privilege id */
117 *priv(rp) = *priv(caller); /* copy from caller */
118 priv(rp)->s_id = priv_id; /* restore privilege id */
119 priv(rp)->s_proc_nr = proc_nr; /* reassociate process nr */
120
121 for (i=0; i< NR_SYS_CHUNKS; i++) /* remove pending: */
122 priv(rp)->s_asyn_pending.chunk[i] = 0; /* - incoming asyn */
123 for (i=0; i< NR_SYS_CHUNKS; i++) /* messages */
124 priv(rp)->s_notify_pending.chunk[i] = 0; /* - notifications */
125 priv(rp)->s_int_pending = 0; /* - interrupts */
126 (void) sigemptyset(&priv(rp)->s_sig_pending); /* - signals */
127 reset_kernel_timer(&priv(rp)->s_alarm_timer); /* - alarm */
128 priv(rp)->s_asyntab= -1; /* - asynsends */
129 priv(rp)->s_asynsize= 0;
130 priv(rp)->s_asynendpoint = rp->p_endpoint;
131 priv(rp)->s_diag_sig = FALSE; /* no request for diag sigs */
132
133 /* Set defaults for privilege bitmaps. */
134 priv(rp)->s_flags= DSRV_F; /* privilege flags */
135 priv(rp)->s_init_flags= DSRV_I; /* initialization flags */
136 priv(rp)->s_trap_mask= DSRV_T; /* allowed traps */
137 memset(&map, 0, sizeof(map));
138 ipc_to_m = DSRV_M; /* allowed targets */
139 if (ipc_to_m == ALL_M) {
140 for (i = 0; i < NR_SYS_PROCS; i++)
141 set_sys_bit(map, i);
142 }
143 fill_sendto_mask(rp, &map);
144 kcalls = DSRV_KC; /* allowed kernel calls */
145 for(i = 0; i < SYS_CALL_MASK_SIZE; i++) {
146 priv(rp)->s_k_call_mask[i] = (kcalls == NO_C ? 0 : (~0));
147 }
148
149 /* Set the default signal managers. */
150 priv(rp)->s_sig_mgr = DSRV_SM;
151 priv(rp)->s_bak_sig_mgr = NONE;
152
153 /* Set defaults for resources: no I/O resources, no memory resources,
154 * no IRQs, no grant table, no ipc filter
155 */
156 priv(rp)->s_nr_io_range= 0;
157 priv(rp)->s_nr_mem_range= 0;
158 priv(rp)->s_nr_irq= 0;
159 priv(rp)->s_grant_table= 0;
160 priv(rp)->s_grant_entries= 0;
161 priv(rp)->s_grant_endpoint = rp->p_endpoint;
162 priv(rp)->s_state_table= 0;
163 priv(rp)->s_state_entries= 0;
164 priv(rp)->s_ipcf= 0;
165
166 /* Override defaults if the caller has supplied a privilege structure. */
167 if (m_ptr->m_lsys_krn_sys_privctl.arg_ptr)
168 {
169 if((r = update_priv(rp, &priv)) != OK) {
170 return r;
171 }
172 }
173
174 return(OK);
175
176 case SYS_PRIV_SET_USER:
177 /* Set a privilege structure of a blocked user process. */
178 if (!RTS_ISSET(rp, RTS_NO_PRIV)) return(EPERM);
179
180 /* Link the process to the privilege structure of the root user
181 * process all the user processes share.
182 */
183 priv(rp) = priv_addr(USER_PRIV_ID);
184
185 return(OK);
186
187 case SYS_PRIV_ADD_IO:
188 if (RTS_ISSET(rp, RTS_NO_PRIV))
189 return(EPERM);
190
191 #if 0 /* XXX -- do we need a call for this? */
192 if (strcmp(rp->p_name, "fxp") == 0 ||
193 strcmp(rp->p_name, "rtl8139") == 0)
194 {
195 printf("setting ipc_stats_target to %d\n", rp->p_endpoint);
196 ipc_stats_target= rp->p_endpoint;
197 }
198 #endif
199
200 /* Get the I/O range */
201 data_copy(caller->p_endpoint, m_ptr->m_lsys_krn_sys_privctl.arg_ptr,
202 KERNEL, (vir_bytes) &io_range, sizeof(io_range));
203 /* Add the I/O range */
204 return priv_add_io(rp, &io_range);
205
206 case SYS_PRIV_ADD_MEM:
207 if (RTS_ISSET(rp, RTS_NO_PRIV))
208 return(EPERM);
209
210 /* Get the memory range */
211 if((r=data_copy(caller->p_endpoint,
212 m_ptr->m_lsys_krn_sys_privctl.arg_ptr, KERNEL,
213 (vir_bytes) &mem_range, sizeof(mem_range))) != OK)
214 return r;
215 /* Add the memory range */
216 return priv_add_mem(rp, &mem_range);
217
218 case SYS_PRIV_ADD_IRQ:
219 if (RTS_ISSET(rp, RTS_NO_PRIV))
220 return(EPERM);
221
222 #if 0
223 /* Only system processes get IRQs? */
224 if (!(priv(rp)->s_flags & SYS_PROC))
225 return EPERM;
226 #endif
227 data_copy(caller->p_endpoint, m_ptr->m_lsys_krn_sys_privctl.arg_ptr,
228 KERNEL, (vir_bytes) &irq, sizeof(irq));
229 /* Add the IRQ. */
230 return priv_add_irq(rp, irq);
231
232 case SYS_PRIV_QUERY_MEM:
233 {
234 phys_bytes addr, limit;
235 struct priv *sp;
236 /* See if a certain process is allowed to map in certain physical
237 * memory.
238 */
239 addr = (phys_bytes) m_ptr->m_lsys_krn_sys_privctl.phys_start;
240 limit = addr + (phys_bytes) m_ptr->m_lsys_krn_sys_privctl.phys_len - 1;
241 if(limit < addr)
242 return EPERM;
243 if(!(sp = priv(rp)))
244 return EPERM;
245 for(i = 0; i < sp->s_nr_mem_range; i++) {
246 if(addr >= sp->s_mem_tab[i].mr_base &&
247 limit <= sp->s_mem_tab[i].mr_limit)
248 return OK;
249 }
250 return EPERM;
251 }
252
253 case SYS_PRIV_UPDATE_SYS:
254 /* Update the privilege structure of a system process. */
255 if(!m_ptr->m_lsys_krn_sys_privctl.arg_ptr) return EINVAL;
256
257 /* Copy privilege structure from caller */
258 if((r=data_copy(caller->p_endpoint,
259 m_ptr->m_lsys_krn_sys_privctl.arg_ptr, KERNEL,
260 (vir_bytes) &priv, sizeof(priv))) != OK)
261 return r;
262
263 /* Override settings in existing privilege structure. */
264 if((r = update_priv(rp, &priv)) != OK) {
265 return r;
266 }
267
268 return(OK);
269
270 default:
271 printf("do_privctl: bad request %d\n",
272 m_ptr->m_lsys_krn_sys_privctl.request);
273 return EINVAL;
274 }
275 }
276
277 /*===========================================================================*
278 * update_priv *
279 *===========================================================================*/
update_priv(struct proc * rp,struct priv * priv)280 static int update_priv(struct proc *rp, struct priv *priv)
281 {
282 /* Update the privilege structure of a given process. */
283
284 int i;
285
286 /* Copy flags and signal managers. */
287 priv(rp)->s_flags = priv->s_flags;
288 priv(rp)->s_init_flags = priv->s_init_flags;
289 priv(rp)->s_sig_mgr = priv->s_sig_mgr;
290 priv(rp)->s_bak_sig_mgr = priv->s_bak_sig_mgr;
291
292 /* Copy IRQs. */
293 if(priv->s_flags & CHECK_IRQ) {
294 if (priv->s_nr_irq < 0 || priv->s_nr_irq > NR_IRQ)
295 return EINVAL;
296 priv(rp)->s_nr_irq= priv->s_nr_irq;
297 for (i= 0; i<priv->s_nr_irq; i++)
298 {
299 priv(rp)->s_irq_tab[i]= priv->s_irq_tab[i];
300 #if PRIV_DEBUG
301 printf("do_privctl: adding IRQ %d for %d\n",
302 priv(rp)->s_irq_tab[i], rp->p_endpoint);
303 #endif
304 }
305 }
306
307 /* Copy I/O ranges. */
308 if(priv->s_flags & CHECK_IO_PORT) {
309 if (priv->s_nr_io_range < 0 || priv->s_nr_io_range > NR_IO_RANGE)
310 return EINVAL;
311 priv(rp)->s_nr_io_range= priv->s_nr_io_range;
312 for (i= 0; i<priv->s_nr_io_range; i++)
313 {
314 priv(rp)->s_io_tab[i]= priv->s_io_tab[i];
315 #if PRIV_DEBUG
316 printf("do_privctl: adding I/O range [%x..%x] for %d\n",
317 priv(rp)->s_io_tab[i].ior_base,
318 priv(rp)->s_io_tab[i].ior_limit,
319 rp->p_endpoint);
320 #endif
321 }
322 }
323
324 /* Copy memory ranges. */
325 if(priv->s_flags & CHECK_MEM) {
326 if (priv->s_nr_mem_range < 0 || priv->s_nr_mem_range > NR_MEM_RANGE)
327 return EINVAL;
328 priv(rp)->s_nr_mem_range= priv->s_nr_mem_range;
329 for (i= 0; i<priv->s_nr_mem_range; i++)
330 {
331 priv(rp)->s_mem_tab[i]= priv->s_mem_tab[i];
332 #if PRIV_DEBUG
333 printf("do_privctl: adding mem range [%x..%x] for %d\n",
334 priv(rp)->s_mem_tab[i].mr_base,
335 priv(rp)->s_mem_tab[i].mr_limit,
336 rp->p_endpoint);
337 #endif
338 }
339 }
340
341 /* Copy trap mask. */
342 priv(rp)->s_trap_mask = priv->s_trap_mask;
343
344 /* Copy target mask. */
345 #if PRIV_DEBUG
346 printf("do_privctl: Setting ipc target mask for %d:");
347 for (i=0; i < NR_SYS_PROCS; i += BITCHUNK_BITS) {
348 printf(" %08x", get_sys_bits(priv->s_ipc_to, i));
349 }
350 printf("\n");
351 #endif
352
353 fill_sendto_mask(rp, &priv->s_ipc_to);
354
355 #if PRIV_DEBUG
356 printf("do_privctl: Set ipc target mask for %d:");
357 for (i=0; i < NR_SYS_PROCS; i += BITCHUNK_BITS) {
358 printf(" %08x", get_sys_bits(priv(rp)->s_ipc_to, i));
359 }
360 printf("\n");
361 #endif
362
363 /* Copy kernel call mask. */
364 memcpy(priv(rp)->s_k_call_mask, priv->s_k_call_mask,
365 sizeof(priv(rp)->s_k_call_mask));
366
367 return OK;
368 }
369
370 #endif /* USE_PRIVCTL */
371
372