syscall messaging 3: Expand the 'header' that goes in front of the syscall
[dragonfly.git] / sys / emulation / linux / i386 / linux_ptrace.c
CommitLineData
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1/*
2 * Copyright (c) 2001 Alexander Kabaev
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * $FreeBSD: src/sys/i386/linux/linux_ptrace.c,v 1.7.4.3 2003/01/03 17:13:23 kan Exp $
c7114eea 29 * $DragonFly: src/sys/emulation/linux/i386/linux_ptrace.c,v 1.6 2003/07/30 00:19:14 dillon Exp $
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30 */
31
32#include "opt_cpu.h"
33
34#include <sys/param.h>
35#include <sys/lock.h>
36#include <sys/proc.h>
37#include <sys/ptrace.h>
38#include <sys/systm.h>
39
40#include <vm/vm.h>
41#include <vm/pmap.h>
42#include <vm/vm_map.h>
43#include <sys/user.h>
44
45#include <machine/md_var.h>
46#include <machine/pcb.h>
47#include <machine/reg.h>
48
49#include <i386/linux/linux.h>
50#include <i386/linux/linux_proto.h>
51
52/*
53 * Linux ptrace requests numbers. Mostly identical to FreeBSD,
54 * except for MD ones and PT_ATTACH/PT_DETACH.
55 */
56#define PTRACE_TRACEME 0
57#define PTRACE_PEEKTEXT 1
58#define PTRACE_PEEKDATA 2
59#define PTRACE_PEEKUSR 3
60#define PTRACE_POKETEXT 4
61#define PTRACE_POKEDATA 5
62#define PTRACE_POKEUSR 6
63#define PTRACE_CONT 7
64#define PTRACE_KILL 8
65#define PTRACE_SINGLESTEP 9
66
67#define PTRACE_ATTACH 16
68#define PTRACE_DETACH 17
69
70#define PTRACE_SYSCALL 24
71
72#define PTRACE_GETREGS 12
73#define PTRACE_SETREGS 13
74#define PTRACE_GETFPREGS 14
75#define PTRACE_SETFPREGS 15
76#define PTRACE_GETFPXREGS 18
77#define PTRACE_SETFPXREGS 19
78
79#define PTRACE_SETOPTIONS 21
80
81/*
82 * Linux keeps debug registers at the following
83 * offset in the user struct
84 */
85#define LINUX_DBREG_OFFSET 252
86#define LINUX_DBREG_SIZE (8*sizeof(l_int))
87
88static __inline__ int
89map_signum(int signum)
90{
91
92 if (signum > 0 && signum <= LINUX_SIGTBLSZ)
93 signum = linux_to_bsd_signal[_SIG_IDX(signum)];
94 return ((signum == SIGSTOP)? 0 : signum);
95}
96
97struct linux_pt_reg {
98 l_long ebx;
99 l_long ecx;
100 l_long edx;
101 l_long esi;
102 l_long edi;
103 l_long ebp;
104 l_long eax;
105 l_int xds;
106 l_int xes;
107 l_int xfs;
108 l_int xgs;
109 l_long orig_eax;
110 l_long eip;
111 l_int xcs;
112 l_long eflags;
113 l_long esp;
114 l_int xss;
115};
116
117/*
118 * Translate i386 ptrace registers between Linux and FreeBSD formats.
119 * The translation is pretty straighforward, for all registers, but
120 * orig_eax on Linux side and r_trapno and r_err in FreeBSD
121 */
122static void
123map_regs_to_linux(struct reg *bsd_r, struct linux_pt_reg *linux_r)
124{
125 linux_r->ebx = bsd_r->r_ebx;
126 linux_r->ecx = bsd_r->r_ecx;
127 linux_r->edx = bsd_r->r_edx;
128 linux_r->esi = bsd_r->r_esi;
129 linux_r->edi = bsd_r->r_edi;
130 linux_r->ebp = bsd_r->r_ebp;
131 linux_r->eax = bsd_r->r_eax;
132 linux_r->xds = bsd_r->r_ds;
133 linux_r->xes = bsd_r->r_es;
134 linux_r->xfs = bsd_r->r_fs;
135 linux_r->xgs = bsd_r->r_gs;
136 linux_r->orig_eax = bsd_r->r_eax;
137 linux_r->eip = bsd_r->r_eip;
138 linux_r->xcs = bsd_r->r_cs;
139 linux_r->eflags = bsd_r->r_eflags;
140 linux_r->esp = bsd_r->r_esp;
141 linux_r->xss = bsd_r->r_ss;
142}
143
144static void
145map_regs_from_linux(struct reg *bsd_r, struct linux_pt_reg *linux_r)
146{
147 bsd_r->r_ebx = linux_r->ebx;
148 bsd_r->r_ecx = linux_r->ecx;
149 bsd_r->r_edx = linux_r->edx;
150 bsd_r->r_esi = linux_r->esi;
151 bsd_r->r_edi = linux_r->edi;
152 bsd_r->r_ebp = linux_r->ebp;
153 bsd_r->r_eax = linux_r->eax;
154 bsd_r->r_ds = linux_r->xds;
155 bsd_r->r_es = linux_r->xes;
156 bsd_r->r_fs = linux_r->xfs;
157 bsd_r->r_gs = linux_r->xgs;
158 bsd_r->r_eip = linux_r->eip;
159 bsd_r->r_cs = linux_r->xcs;
160 bsd_r->r_eflags = linux_r->eflags;
161 bsd_r->r_esp = linux_r->esp;
162 bsd_r->r_ss = linux_r->xss;
163}
164
165struct linux_pt_fpreg {
166 l_long cwd;
167 l_long swd;
168 l_long twd;
169 l_long fip;
170 l_long fcs;
171 l_long foo;
172 l_long fos;
173 l_long st_space[2*10];
174};
175
176static void
177map_fpregs_to_linux(struct fpreg *bsd_r, struct linux_pt_fpreg *linux_r)
178{
179 linux_r->cwd = bsd_r->fpr_env[0];
180 linux_r->swd = bsd_r->fpr_env[1];
181 linux_r->twd = bsd_r->fpr_env[2];
182 linux_r->fip = bsd_r->fpr_env[3];
183 linux_r->fcs = bsd_r->fpr_env[4];
184 linux_r->foo = bsd_r->fpr_env[5];
185 linux_r->fos = bsd_r->fpr_env[6];
186 bcopy(bsd_r->fpr_acc, linux_r->st_space, sizeof(linux_r->st_space));
187}
188
189static void
190map_fpregs_from_linux(struct fpreg *bsd_r, struct linux_pt_fpreg *linux_r)
191{
192 bsd_r->fpr_env[0] = linux_r->cwd;
193 bsd_r->fpr_env[1] = linux_r->swd;
194 bsd_r->fpr_env[2] = linux_r->twd;
195 bsd_r->fpr_env[3] = linux_r->fip;
196 bsd_r->fpr_env[4] = linux_r->fcs;
197 bsd_r->fpr_env[5] = linux_r->foo;
198 bsd_r->fpr_env[6] = linux_r->fos;
199 bcopy(bsd_r->fpr_acc, linux_r->st_space, sizeof(bsd_r->fpr_acc));
200}
201
202struct linux_pt_fpxreg {
203 l_ushort cwd;
204 l_ushort swd;
205 l_ushort twd;
206 l_ushort fop;
207 l_long fip;
208 l_long fcs;
209 l_long foo;
210 l_long fos;
211 l_long mxcsr;
212 l_long reserved;
213 l_long st_space[32];
214 l_long xmm_space[32];
215 l_long padding[56];
216};
217
218#ifdef CPU_ENABLE_SSE
219static int
220linux_proc_read_fpxregs(struct proc *p, struct linux_pt_fpxreg *fpxregs)
221{
222 int error;
223
224 error = 0;
225 if (cpu_fxsr == 0 || (p->p_flag & P_INMEM) == 0)
226 error = EIO;
227 else
b7c628e4 228 bcopy(&p->p_thread->td_pcb->pcb_save.sv_xmm,
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229 fpxregs, sizeof(*fpxregs));
230 return (error);
231}
232
233static int
234linux_proc_write_fpxregs(struct proc *p, struct linux_pt_fpxreg *fpxregs)
235{
236 int error;
237
238 error = 0;
239 if (cpu_fxsr == 0 || (p->p_flag & P_INMEM) == 0)
240 error = EIO;
241 else
b7c628e4 242 bcopy(fpxregs, &p->p_thread->td_pcb->pcb_save.sv_xmm,
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243 sizeof(*fpxregs));
244 return (error);
245}
246#endif
247
248int
41c20dac 249linux_ptrace(struct linux_ptrace_args *uap)
984263bc 250{
41c20dac 251 struct proc *curp = curproc;
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252 union {
253 struct linux_pt_reg reg;
254 struct linux_pt_fpreg fpreg;
255 struct linux_pt_fpxreg fpxreg;
256 } r;
257 union {
258 struct reg bsd_reg;
259 struct fpreg bsd_fpreg;
260 struct dbreg bsd_dbreg;
261 } u;
262 void *addr;
263 pid_t pid;
264 int error, req;
265
266 error = 0;
267
268 /* by default, just copy data intact */
269 req = uap->req;
270 pid = (pid_t)uap->pid;
271 addr = (void *)uap->addr;
272
273 switch (req) {
274 case PTRACE_TRACEME:
275 case PTRACE_POKETEXT:
276 case PTRACE_POKEDATA:
277 case PTRACE_KILL:
90b9818c 278 error = kern_ptrace(curp, req, pid, addr, uap->data,
c7114eea 279 &uap->sysmsg_result);
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280 break;
281 case PTRACE_PEEKTEXT:
282 case PTRACE_PEEKDATA: {
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283 /* need to preserve return value, use dummy */
284 l_int rval = 0;
285 error = kern_ptrace(curp, req, pid, addr, 0, &rval);
286 if (error == 0) {
287 error = copyout(&rval, (caddr_t)uap->data, sizeof(l_int));
288 }
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289 break;
290 }
291 case PTRACE_DETACH:
292 error = kern_ptrace(curp, PT_DETACH, pid, (void *)1,
c7114eea 293 map_signum(uap->data), &uap->sysmsg_result);
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294 break;
295 case PTRACE_SINGLESTEP:
296 case PTRACE_CONT:
297 error = kern_ptrace(curp, req, pid, (void *)1,
c7114eea 298 map_signum(uap->data), &uap->sysmsg_result);
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299 break;
300 case PTRACE_ATTACH:
90b9818c 301 error = kern_ptrace(curp, PT_ATTACH, pid, addr, uap->data,
c7114eea 302 &uap->sysmsg_result);
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303 break;
304 case PTRACE_GETREGS:
305 /* Linux is using data where FreeBSD is using addr */
90b9818c 306 error = kern_ptrace(curp, PT_GETREGS, pid, &u.bsd_reg, 0,
c7114eea 307 &uap->sysmsg_result);
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308 if (error == 0) {
309 map_regs_to_linux(&u.bsd_reg, &r.reg);
310 error = copyout(&r.reg, (caddr_t)uap->data,
311 sizeof(r.reg));
312 }
313 break;
314 case PTRACE_SETREGS:
315 /* Linux is using data where FreeBSD is using addr */
316 error = copyin((caddr_t)uap->data, &r.reg, sizeof(r.reg));
317 if (error == 0) {
318 map_regs_from_linux(&u.bsd_reg, &r.reg);
c7114eea 319 error = kern_ptrace(curp, PT_SETREGS, pid, &u.bsd_reg, 0, &uap->sysmsg_result);
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320 }
321 break;
322 case PTRACE_GETFPREGS:
323 /* Linux is using data where FreeBSD is using addr */
90b9818c 324 error = kern_ptrace(curp, PT_GETFPREGS, pid, &u.bsd_fpreg, 0,
c7114eea 325 &uap->sysmsg_result);
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326 if (error == 0) {
327 map_fpregs_to_linux(&u.bsd_fpreg, &r.fpreg);
328 error = copyout(&r.fpreg, (caddr_t)uap->data,
329 sizeof(r.fpreg));
330 }
331 break;
332 case PTRACE_SETFPREGS:
333 /* Linux is using data where FreeBSD is using addr */
334 error = copyin((caddr_t)uap->data, &r.fpreg, sizeof(r.fpreg));
335 if (error == 0) {
336 map_fpregs_from_linux(&u.bsd_fpreg, &r.fpreg);
337 error = kern_ptrace(curp, PT_SETFPREGS, pid,
c7114eea 338 &u.bsd_fpreg, 0, &uap->sysmsg_result);
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339 }
340 break;
341 case PTRACE_SETFPXREGS:
342#ifdef CPU_ENABLE_SSE
343 error = copyin((caddr_t)uap->data, &r.fpxreg,
344 sizeof(r.fpxreg));
345 if (error)
346 break;
347#endif
348 /* FALL THROUGH */
349 case PTRACE_GETFPXREGS: {
350#ifdef CPU_ENABLE_SSE
351 struct proc *p;
352
353 if (sizeof(struct linux_pt_fpxreg) != sizeof(struct savexmm)) {
354 static int once = 0;
355 if (!once) {
356 printf("linux: savexmm != linux_pt_fpxreg\n");
357 once = 1;
358 }
359 error = EIO;
360 break;
361 }
362
363 if ((p = pfind(uap->pid)) == NULL) {
364 error = ESRCH;
365 break;
366 }
367
41c20dac 368 if (!PRISON_CHECK(curp->p_ucred, p->p_ucred)) {
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369 error = ESRCH;
370 goto fail;
371 }
372
373 /* System processes can't be debugged. */
374 if ((p->p_flag & P_SYSTEM) != 0) {
375 error = EINVAL;
376 goto fail;
377 }
378
379 /* not being traced... */
380 if ((p->p_flag & P_TRACED) == 0) {
381 error = EPERM;
382 goto fail;
383 }
384
385 /* not being traced by YOU */
386 if (p->p_pptr != curp) {
387 error = EBUSY;
388 goto fail;
389 }
390
391 /* not currently stopped */
392 if ((p->p_flag & (P_TRACED|P_WAITED)) == 0) {
393 error = EBUSY;
394 goto fail;
395 }
396
397 if (req == PTRACE_GETFPXREGS) {
398 PHOLD(p);
399 error = linux_proc_read_fpxregs(p, &r.fpxreg);
400 PRELE(p);
401 if (error == 0)
402 error = copyout(&r.fpxreg, (caddr_t)uap->data,
403 sizeof(r.fpxreg));
404 } else {
405 /* clear dangerous bits exactly as Linux does*/
406 r.fpxreg.mxcsr &= 0xffbf;
407 PHOLD(p);
408 error = linux_proc_write_fpxregs(p, &r.fpxreg);
409 PRELE(p);
410 }
411 break;
412
413 fail:
414#else
415 error = EIO;
416#endif
417 break;
418 }
419 case PTRACE_PEEKUSR:
420 case PTRACE_POKEUSR: {
421 error = EIO;
422
423 /* check addr for alignment */
424 if (uap->addr < 0 || uap->addr & (sizeof(l_int) - 1))
425 break;
426 /*
427 * Allow linux programs to access register values in
428 * user struct. We simulate this through PT_GET/SETREGS
429 * as necessary.
430 */
431 if (uap->addr < sizeof(struct linux_pt_reg)) {
c7114eea 432 error = kern_ptrace(curp, PT_GETREGS, pid, &u.bsd_reg, 0, &uap->sysmsg_result);
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433 if (error != 0)
434 break;
435
436 map_regs_to_linux(&u.bsd_reg, &r.reg);
437 if (req == PTRACE_PEEKUSR) {
438 error = copyout((char *)&r.reg + uap->addr,
439 (caddr_t)uap->data, sizeof(l_int));
440 break;
441 }
442
443 *(l_int *)((char *)&r.reg + uap->addr) =
444 (l_int)uap->data;
445
446 map_regs_from_linux(&u.bsd_reg, &r.reg);
c7114eea 447 error = kern_ptrace(curp, PT_SETREGS, pid, &u.bsd_reg, 0, &uap->sysmsg_result);
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448 }
449
450 /*
451 * Simulate debug registers access
452 */
453 if (uap->addr >= LINUX_DBREG_OFFSET &&
454 uap->addr <= LINUX_DBREG_OFFSET + LINUX_DBREG_SIZE) {
90b9818c 455 error = kern_ptrace(curp, PT_GETDBREGS, pid,
c7114eea 456 &u.bsd_dbreg, 0, &uap->sysmsg_result);
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457 if (error != 0)
458 break;
459
460 uap->addr -= LINUX_DBREG_OFFSET;
461 if (req == PTRACE_PEEKUSR) {
462 error = copyout((char *)&u.bsd_dbreg +
463 uap->addr, (caddr_t)uap->data,
464 sizeof(l_int));
465 break;
466 }
467
468 *(l_int *)((char *)&u.bsd_dbreg + uap->addr) =
469 uap->data;
470 error = kern_ptrace(curp, PT_SETDBREGS, pid,
c7114eea 471 &u.bsd_dbreg, 0, &uap->sysmsg_result);
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472 }
473
474 break;
475 }
476 case PTRACE_SYSCALL:
477 /* fall through */
478 default:
479 printf("linux: ptrace(%u, ...) not implemented\n",
480 (unsigned int)uap->req);
481 error = EINVAL;
482 break;
483 }
484
485 return (error);
486}