xref: /openbmc/qemu/bsd-user/freebsd/os-syscall.c (revision e800e6c5)
1 /*
2  *  BSD syscalls
3  *
4  *  Copyright (c) 2003-2008 Fabrice Bellard
5  *  Copyright (c) 2013-2014 Stacey D. Son
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
19  */
20 #include "qemu/osdep.h"
21 #include "qemu/cutils.h"
22 #include "qemu/path.h"
23 #include <sys/syscall.h>
24 #include <sys/cdefs.h>
25 #include <sys/param.h>
26 #include <sys/mount.h>
27 #include <sys/sysctl.h>
28 #include <utime.h>
29 
30 #include "include/gdbstub/syscalls.h"
31 
32 #include "qemu.h"
33 #include "signal-common.h"
34 #include "user/syscall-trace.h"
35 
36 #include "bsd-file.h"
37 #include "bsd-proc.h"
38 
39 /* *BSD dependent syscall shims */
40 #include "os-stat.h"
41 
42 /* I/O */
43 safe_syscall3(int, open, const char *, path, int, flags, mode_t, mode);
44 safe_syscall4(int, openat, int, fd, const char *, path, int, flags, mode_t,
45     mode);
46 
47 safe_syscall3(ssize_t, read, int, fd, void *, buf, size_t, nbytes);
48 safe_syscall4(ssize_t, pread, int, fd, void *, buf, size_t, nbytes, off_t,
49     offset);
50 safe_syscall3(ssize_t, readv, int, fd, const struct iovec *, iov, int, iovcnt);
51 safe_syscall4(ssize_t, preadv, int, fd, const struct iovec *, iov, int, iovcnt,
52     off_t, offset);
53 
54 safe_syscall3(ssize_t, write, int, fd, void *, buf, size_t, nbytes);
55 safe_syscall4(ssize_t, pwrite, int, fd, void *, buf, size_t, nbytes, off_t,
56     offset);
57 safe_syscall3(ssize_t, writev, int, fd, const struct iovec *, iov, int, iovcnt);
58 safe_syscall4(ssize_t, pwritev, int, fd, const struct iovec *, iov, int, iovcnt,
59     off_t, offset);
60 
61 void target_set_brk(abi_ulong new_brk)
62 {
63 }
64 
65 /*
66  * errno conversion.
67  */
68 abi_long get_errno(abi_long ret)
69 {
70     if (ret == -1) {
71         return -host_to_target_errno(errno);
72     } else {
73         return ret;
74     }
75 }
76 
77 int host_to_target_errno(int err)
78 {
79     /*
80      * All the BSDs have the property that the error numbers are uniform across
81      * all architectures for a given BSD, though they may vary between different
82      * BSDs.
83      */
84     return err;
85 }
86 
87 bool is_error(abi_long ret)
88 {
89     return (abi_ulong)ret >= (abi_ulong)(-4096);
90 }
91 
92 /*
93  * Unlocks a iovec. Unlike unlock_iovec, it assumes the tvec array itself is
94  * already locked from target_addr. It will be unlocked as well as all the iovec
95  * elements.
96  */
97 static void helper_unlock_iovec(struct target_iovec *target_vec,
98                                 abi_ulong target_addr, struct iovec *vec,
99                                 int count, int copy)
100 {
101     for (int i = 0; i < count; i++) {
102         abi_ulong base = tswapal(target_vec[i].iov_base);
103 
104         if (vec[i].iov_base) {
105             unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0);
106         }
107     }
108     unlock_user(target_vec, target_addr, 0);
109 }
110 
111 struct iovec *lock_iovec(int type, abi_ulong target_addr,
112         int count, int copy)
113 {
114     struct target_iovec *target_vec;
115     struct iovec *vec;
116     abi_ulong total_len, max_len;
117     int i;
118     int err = 0;
119 
120     if (count == 0) {
121         errno = 0;
122         return NULL;
123     }
124     if (count < 0 || count > IOV_MAX) {
125         errno = EINVAL;
126         return NULL;
127     }
128 
129     vec = g_try_new0(struct iovec, count);
130     if (vec == NULL) {
131         errno = ENOMEM;
132         return NULL;
133     }
134 
135     target_vec = lock_user(VERIFY_READ, target_addr,
136                            count * sizeof(struct target_iovec), 1);
137     if (target_vec == NULL) {
138         err = EFAULT;
139         goto fail2;
140     }
141 
142     max_len = 0x7fffffff & MIN(TARGET_PAGE_MASK, PAGE_MASK);
143     total_len = 0;
144 
145     for (i = 0; i < count; i++) {
146         abi_ulong base = tswapal(target_vec[i].iov_base);
147         abi_long len = tswapal(target_vec[i].iov_len);
148 
149         if (len < 0) {
150             err = EINVAL;
151             goto fail;
152         } else if (len == 0) {
153             /* Zero length pointer is ignored. */
154             vec[i].iov_base = 0;
155         } else {
156             vec[i].iov_base = lock_user(type, base, len, copy);
157             /*
158              * If the first buffer pointer is bad, this is a fault.  But
159              * subsequent bad buffers will result in a partial write; this is
160              * realized by filling the vector with null pointers and zero
161              * lengths.
162              */
163             if (!vec[i].iov_base) {
164                 if (i == 0) {
165                     err = EFAULT;
166                     goto fail;
167                 } else {
168                     /*
169                      * Fail all the subsequent addresses, they are already
170                      * zero'd.
171                      */
172                     goto out;
173                 }
174             }
175             if (len > max_len - total_len) {
176                 len = max_len - total_len;
177             }
178         }
179         vec[i].iov_len = len;
180         total_len += len;
181     }
182 out:
183     unlock_user(target_vec, target_addr, 0);
184     return vec;
185 
186 fail:
187     helper_unlock_iovec(target_vec, target_addr, vec, i, copy);
188 fail2:
189     g_free(vec);
190     errno = err;
191     return NULL;
192 }
193 
194 void unlock_iovec(struct iovec *vec, abi_ulong target_addr,
195         int count, int copy)
196 {
197     struct target_iovec *target_vec;
198 
199     target_vec = lock_user(VERIFY_READ, target_addr,
200                            count * sizeof(struct target_iovec), 1);
201     if (target_vec) {
202         helper_unlock_iovec(target_vec, target_addr, vec, count, copy);
203     }
204 
205     g_free(vec);
206 }
207 
208 /*
209  * All errnos that freebsd_syscall() returns must be -TARGET_<errcode>.
210  */
211 static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
212                                 abi_long arg2, abi_long arg3, abi_long arg4,
213                                 abi_long arg5, abi_long arg6, abi_long arg7,
214                                 abi_long arg8)
215 {
216     abi_long ret;
217 
218     switch (num) {
219         /*
220          * process system calls
221          */
222     case TARGET_FREEBSD_NR_exit: /* exit(2) */
223         ret = do_bsd_exit(cpu_env, arg1);
224         break;
225 
226         /*
227          * File system calls.
228          */
229     case TARGET_FREEBSD_NR_read: /* read(2) */
230         ret = do_bsd_read(arg1, arg2, arg3);
231         break;
232 
233     case TARGET_FREEBSD_NR_pread: /* pread(2) */
234         ret = do_bsd_pread(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
235         break;
236 
237     case TARGET_FREEBSD_NR_readv: /* readv(2) */
238         ret = do_bsd_readv(arg1, arg2, arg3);
239         break;
240 
241     case TARGET_FREEBSD_NR_preadv: /* preadv(2) */
242         ret = do_bsd_preadv(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
243 
244     case TARGET_FREEBSD_NR_write: /* write(2) */
245         ret = do_bsd_write(arg1, arg2, arg3);
246         break;
247 
248     case TARGET_FREEBSD_NR_pwrite: /* pwrite(2) */
249         ret = do_bsd_pwrite(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
250         break;
251 
252     case TARGET_FREEBSD_NR_writev: /* writev(2) */
253         ret = do_bsd_writev(arg1, arg2, arg3);
254         break;
255 
256     case TARGET_FREEBSD_NR_pwritev: /* pwritev(2) */
257         ret = do_bsd_pwritev(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
258         break;
259 
260     case TARGET_FREEBSD_NR_open: /* open(2) */
261         ret = do_bsd_open(arg1, arg2, arg3);
262         break;
263 
264     case TARGET_FREEBSD_NR_openat: /* openat(2) */
265         ret = do_bsd_openat(arg1, arg2, arg3, arg4);
266         break;
267 
268     case TARGET_FREEBSD_NR_close: /* close(2) */
269         ret = do_bsd_close(arg1);
270         break;
271 
272     case TARGET_FREEBSD_NR_fdatasync: /* fdatasync(2) */
273         ret = do_bsd_fdatasync(arg1);
274         break;
275 
276     case TARGET_FREEBSD_NR_fsync: /* fsync(2) */
277         ret = do_bsd_fsync(arg1);
278         break;
279 
280     case TARGET_FREEBSD_NR_freebsd12_closefrom: /* closefrom(2) */
281         ret = do_bsd_closefrom(arg1);
282         break;
283 
284     case TARGET_FREEBSD_NR_revoke: /* revoke(2) */
285         ret = do_bsd_revoke(arg1);
286         break;
287 
288     case TARGET_FREEBSD_NR_access: /* access(2) */
289         ret = do_bsd_access(arg1, arg2);
290         break;
291 
292     case TARGET_FREEBSD_NR_eaccess: /* eaccess(2) */
293         ret = do_bsd_eaccess(arg1, arg2);
294         break;
295 
296     case TARGET_FREEBSD_NR_faccessat: /* faccessat(2) */
297         ret = do_bsd_faccessat(arg1, arg2, arg3, arg4);
298         break;
299 
300     case TARGET_FREEBSD_NR_chdir: /* chdir(2) */
301         ret = do_bsd_chdir(arg1);
302         break;
303 
304     case TARGET_FREEBSD_NR_fchdir: /* fchdir(2) */
305         ret = do_bsd_fchdir(arg1);
306         break;
307 
308     case TARGET_FREEBSD_NR_rename: /* rename(2) */
309         ret = do_bsd_rename(arg1, arg2);
310         break;
311 
312     case TARGET_FREEBSD_NR_renameat: /* renameat(2) */
313         ret = do_bsd_renameat(arg1, arg2, arg3, arg4);
314         break;
315 
316     case TARGET_FREEBSD_NR_link: /* link(2) */
317         ret = do_bsd_link(arg1, arg2);
318         break;
319 
320     case TARGET_FREEBSD_NR_linkat: /* linkat(2) */
321         ret = do_bsd_linkat(arg1, arg2, arg3, arg4, arg5);
322         break;
323 
324     case TARGET_FREEBSD_NR_unlink: /* unlink(2) */
325         ret = do_bsd_unlink(arg1);
326         break;
327 
328     case TARGET_FREEBSD_NR_unlinkat: /* unlinkat(2) */
329         ret = do_bsd_unlinkat(arg1, arg2, arg3);
330         break;
331 
332     case TARGET_FREEBSD_NR_mkdir: /* mkdir(2) */
333         ret = do_bsd_mkdir(arg1, arg2);
334         break;
335 
336     case TARGET_FREEBSD_NR_mkdirat: /* mkdirat(2) */
337         ret = do_bsd_mkdirat(arg1, arg2, arg3);
338         break;
339 
340     case TARGET_FREEBSD_NR_rmdir: /* rmdir(2) (XXX no rmdirat()?) */
341         ret = do_bsd_rmdir(arg1);
342         break;
343 
344     case TARGET_FREEBSD_NR___getcwd: /* undocumented __getcwd() */
345         ret = do_bsd___getcwd(arg1, arg2);
346         break;
347 
348     case TARGET_FREEBSD_NR_dup: /* dup(2) */
349         ret = do_bsd_dup(arg1);
350         break;
351 
352     case TARGET_FREEBSD_NR_dup2: /* dup2(2) */
353         ret = do_bsd_dup2(arg1, arg2);
354         break;
355 
356     case TARGET_FREEBSD_NR_truncate: /* truncate(2) */
357         ret = do_bsd_truncate(cpu_env, arg1, arg2, arg3, arg4);
358         break;
359 
360     case TARGET_FREEBSD_NR_ftruncate: /* ftruncate(2) */
361         ret = do_bsd_ftruncate(cpu_env, arg1, arg2, arg3, arg4);
362         break;
363 
364     case TARGET_FREEBSD_NR_acct: /* acct(2) */
365         ret = do_bsd_acct(arg1);
366         break;
367 
368     case TARGET_FREEBSD_NR_sync: /* sync(2) */
369         ret = do_bsd_sync();
370         break;
371 
372     case TARGET_FREEBSD_NR_mount: /* mount(2) */
373         ret = do_bsd_mount(arg1, arg2, arg3, arg4);
374         break;
375 
376     case TARGET_FREEBSD_NR_unmount: /* unmount(2) */
377         ret = do_bsd_unmount(arg1, arg2);
378         break;
379 
380     case TARGET_FREEBSD_NR_nmount: /* nmount(2) */
381         ret = do_bsd_nmount(arg1, arg2, arg3);
382         break;
383 
384     case TARGET_FREEBSD_NR_symlink: /* symlink(2) */
385         ret = do_bsd_symlink(arg1, arg2);
386         break;
387 
388     case TARGET_FREEBSD_NR_symlinkat: /* symlinkat(2) */
389         ret = do_bsd_symlinkat(arg1, arg2, arg3);
390         break;
391 
392     case TARGET_FREEBSD_NR_readlink: /* readlink(2) */
393         ret = do_bsd_readlink(cpu_env, arg1, arg2, arg3);
394         break;
395 
396     case TARGET_FREEBSD_NR_readlinkat: /* readlinkat(2) */
397         ret = do_bsd_readlinkat(arg1, arg2, arg3, arg4);
398         break;
399 
400     case TARGET_FREEBSD_NR_chmod: /* chmod(2) */
401         ret = do_bsd_chmod(arg1, arg2);
402         break;
403 
404     case TARGET_FREEBSD_NR_fchmod: /* fchmod(2) */
405         ret = do_bsd_fchmod(arg1, arg2);
406         break;
407 
408     case TARGET_FREEBSD_NR_lchmod: /* lchmod(2) */
409         ret = do_bsd_lchmod(arg1, arg2);
410         break;
411 
412     case TARGET_FREEBSD_NR_fchmodat: /* fchmodat(2) */
413         ret = do_bsd_fchmodat(arg1, arg2, arg3, arg4);
414         break;
415 
416     case TARGET_FREEBSD_NR_freebsd11_mknod: /* mknod(2) */
417         ret = do_bsd_freebsd11_mknod(arg1, arg2, arg3);
418         break;
419 
420     case TARGET_FREEBSD_NR_freebsd11_mknodat: /* mknodat(2) */
421         ret = do_bsd_freebsd11_mknodat(arg1, arg2, arg3, arg4);
422         break;
423 
424     case TARGET_FREEBSD_NR_mknodat: /* mknodat(2) */
425         ret = do_bsd_mknodat(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
426         break;
427 
428     case TARGET_FREEBSD_NR_chown: /* chown(2) */
429         ret = do_bsd_chown(arg1, arg2, arg3);
430         break;
431 
432     case TARGET_FREEBSD_NR_fchown: /* fchown(2) */
433         ret = do_bsd_fchown(arg1, arg2, arg3);
434         break;
435 
436     case TARGET_FREEBSD_NR_lchown: /* lchown(2) */
437         ret = do_bsd_lchown(arg1, arg2, arg3);
438         break;
439 
440     case TARGET_FREEBSD_NR_fchownat: /* fchownat(2) */
441         ret = do_bsd_fchownat(arg1, arg2, arg3, arg4, arg5);
442         break;
443 
444     case TARGET_FREEBSD_NR_chflags: /* chflags(2) */
445         ret = do_bsd_chflags(arg1, arg2);
446         break;
447 
448     case TARGET_FREEBSD_NR_lchflags: /* lchflags(2) */
449         ret = do_bsd_lchflags(arg1, arg2);
450         break;
451 
452     case TARGET_FREEBSD_NR_fchflags: /* fchflags(2) */
453         ret = do_bsd_fchflags(arg1, arg2);
454         break;
455 
456     case TARGET_FREEBSD_NR_chroot: /* chroot(2) */
457         ret = do_bsd_chroot(arg1);
458         break;
459 
460     case TARGET_FREEBSD_NR_flock: /* flock(2) */
461         ret = do_bsd_flock(arg1, arg2);
462         break;
463 
464     case TARGET_FREEBSD_NR_mkfifo: /* mkfifo(2) */
465         ret = do_bsd_mkfifo(arg1, arg2);
466         break;
467 
468     case TARGET_FREEBSD_NR_mkfifoat: /* mkfifoat(2) */
469         ret = do_bsd_mkfifoat(arg1, arg2, arg3);
470         break;
471 
472     case TARGET_FREEBSD_NR_pathconf: /* pathconf(2) */
473         ret = do_bsd_pathconf(arg1, arg2);
474         break;
475 
476     case TARGET_FREEBSD_NR_lpathconf: /* lpathconf(2) */
477         ret = do_bsd_lpathconf(arg1, arg2);
478         break;
479 
480     case TARGET_FREEBSD_NR_fpathconf: /* fpathconf(2) */
481         ret = do_bsd_fpathconf(arg1, arg2);
482         break;
483 
484     case TARGET_FREEBSD_NR_undelete: /* undelete(2) */
485         ret = do_bsd_undelete(arg1);
486         break;
487 
488         /*
489          * stat system calls
490          */
491     case TARGET_FREEBSD_NR_freebsd11_stat: /* stat(2) */
492         ret = do_freebsd11_stat(arg1, arg2);
493         break;
494 
495     case TARGET_FREEBSD_NR_freebsd11_lstat: /* lstat(2) */
496         ret = do_freebsd11_lstat(arg1, arg2);
497         break;
498 
499     case TARGET_FREEBSD_NR_freebsd11_fstat: /* fstat(2) */
500         ret = do_freebsd11_fstat(arg1, arg2);
501         break;
502 
503     case TARGET_FREEBSD_NR_fstat: /* fstat(2) */
504         ret = do_freebsd_fstat(arg1, arg2);
505         break;
506 
507     case TARGET_FREEBSD_NR_freebsd11_fstatat: /* fstatat(2) */
508         ret = do_freebsd11_fstatat(arg1, arg2, arg3, arg4);
509         break;
510 
511     case TARGET_FREEBSD_NR_fstatat: /* fstatat(2) */
512         ret = do_freebsd_fstatat(arg1, arg2, arg3, arg4);
513         break;
514 
515     case TARGET_FREEBSD_NR_freebsd11_nstat: /* undocumented */
516         ret = do_freebsd11_nstat(arg1, arg2);
517         break;
518 
519     case TARGET_FREEBSD_NR_freebsd11_nfstat: /* undocumented */
520         ret = do_freebsd11_nfstat(arg1, arg2);
521         break;
522 
523     case TARGET_FREEBSD_NR_freebsd11_nlstat: /* undocumented */
524         ret = do_freebsd11_nlstat(arg1, arg2);
525         break;
526 
527         /*
528          * sys{ctl, arch, call}
529          */
530     case TARGET_FREEBSD_NR___sysctl: /* sysctl(3) */
531         ret = do_freebsd_sysctl(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
532         break;
533 
534     case TARGET_FREEBSD_NR___sysctlbyname: /* sysctlbyname(2) */
535         ret = do_freebsd_sysctlbyname(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
536         break;
537 
538     case TARGET_FREEBSD_NR_sysarch: /* sysarch(2) */
539         ret = do_freebsd_sysarch(cpu_env, arg1, arg2);
540         break;
541 
542     default:
543         qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num);
544         ret = -TARGET_ENOSYS;
545         break;
546     }
547 
548     return ret;
549 }
550 
551 /*
552  * do_freebsd_syscall() should always have a single exit point at the end so
553  * that actions, such as logging of syscall results, can be performed. This
554  * as a wrapper around freebsd_syscall() so that actually happens. Since
555  * that is a singleton, modern compilers will inline it anyway...
556  */
557 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
558                             abi_long arg2, abi_long arg3, abi_long arg4,
559                             abi_long arg5, abi_long arg6, abi_long arg7,
560                             abi_long arg8)
561 {
562     abi_long ret;
563 
564     if (do_strace) {
565         print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
566     }
567 
568     ret = freebsd_syscall(cpu_env, num, arg1, arg2, arg3, arg4, arg5, arg6,
569                           arg7, arg8);
570     if (do_strace) {
571         print_freebsd_syscall_ret(num, ret);
572     }
573 
574     return ret;
575 }
576 
577 void syscall_init(void)
578 {
579 }
580