bsd-user/freebsd/os-syscall.c

   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
  21 /*
  22  * We need the FreeBSD "legacy" definitions. Rust needs the FreeBSD 11 system
  23  * calls since it doesn't use libc at all, so we have to emulate that despite
  24  * FreeBSD 11 being EOL'd.
  25  */
  26 #define _WANT_FREEBSD11_STAT
  27 #define _WANT_FREEBSD11_STATFS
  28 #define _WANT_FREEBSD11_DIRENT
  29 #define _WANT_KERNEL_ERRNO
  30 #define _WANT_SEMUN
  31 #include "qemu/osdep.h"
  32 #include "qemu/cutils.h"
  33 #include "qemu/path.h"
  34 #include <sys/syscall.h>
  35 #include <sys/cdefs.h>
  36 #include <sys/param.h>
  37 #include <sys/mount.h>
  38 #include <sys/sysctl.h>
  39 #include <utime.h>
  40
  41 #include "qemu.h"
  42 #include "signal-common.h"
  43 #include "user/syscall-trace.h"
  44
  45 #include "bsd-file.h"
  46 #include "bsd-proc.h"
  47
  48 /* I/O */
  49 safe_syscall3(int, open, const char *, path, int, flags, mode_t, mode);
  50 safe_syscall4(int, openat, int, fd, const char *, path, int, flags, mode_t,
  51     mode);
  52
  53 safe_syscall3(ssize_t, read, int, fd, void *, buf, size_t, nbytes);
  54 safe_syscall4(ssize_t, pread, int, fd, void *, buf, size_t, nbytes, off_t,
  55     offset);
  56 safe_syscall3(ssize_t, readv, int, fd, const struct iovec *, iov, int, iovcnt);
  57 safe_syscall4(ssize_t, preadv, int, fd, const struct iovec *, iov, int, iovcnt,
  58     off_t, offset);
  59
  60 safe_syscall3(ssize_t, write, int, fd, void *, buf, size_t, nbytes);
  61 safe_syscall4(ssize_t, pwrite, int, fd, void *, buf, size_t, nbytes, off_t,
  62     offset);
  63 safe_syscall3(ssize_t, writev, int, fd, const struct iovec *, iov, int, iovcnt);
  64 safe_syscall4(ssize_t, pwritev, int, fd, const struct iovec *, iov, int, iovcnt,
  65     off_t, offset);
  66
  67 void target_set_brk(abi_ulong new_brk)
  68 {
  69 }
  70
  71 /*
  72  * errno conversion.
  73  */
  74 abi_long get_errno(abi_long ret)
  75 {
  76     if (ret == -1) {
  77         return -host_to_target_errno(errno);
  78     } else {
  79         return ret;
  80     }
  81 }
  82
  83 int host_to_target_errno(int err)
  84 {
  85     /*
  86      * All the BSDs have the property that the error numbers are uniform across
  87      * all architectures for a given BSD, though they may vary between different
  88      * BSDs.
  89      */
  90     return err;
  91 }
  92
  93 bool is_error(abi_long ret)
  94 {
  95     return (abi_ulong)ret >= (abi_ulong)(-4096);
  96 }
  97
  98 /*
  99  * Unlocks a iovec. Unlike unlock_iovec, it assumes the tvec array itself is
 100  * already locked from target_addr. It will be unlocked as well as all the iovec
 101  * elements.
 102  */
 103 static void helper_unlock_iovec(struct target_iovec *target_vec,
 104                                 abi_ulong target_addr, struct iovec *vec,
 105                                 int count, int copy)
 106 {
 107     for (int i = 0; i < count; i++) {
 108         abi_ulong base = tswapal(target_vec[i].iov_base);
 109
 110         if (vec[i].iov_base) {
 111             unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0);
 112         }
 113     }
 114     unlock_user(target_vec, target_addr, 0);
 115 }
 116
 117 struct iovec *lock_iovec(int type, abi_ulong target_addr,
 118         int count, int copy)
 119 {
 120     struct target_iovec *target_vec;
 121     struct iovec *vec;
 122     abi_ulong total_len, max_len;
 123     int i;
 124     int err = 0;
 125
 126     if (count == 0) {
 127         errno = 0;
 128         return NULL;
 129     }
 130     if (count < 0 || count > IOV_MAX) {
 131         errno = EINVAL;
 132         return NULL;
 133     }
 134
 135     vec = g_try_new0(struct iovec, count);
 136     if (vec == NULL) {
 137         errno = ENOMEM;
 138         return NULL;
 139     }
 140
 141     target_vec = lock_user(VERIFY_READ, target_addr,
 142                            count * sizeof(struct target_iovec), 1);
 143     if (target_vec == NULL) {
 144         err = EFAULT;
 145         goto fail2;
 146     }
 147
 148     max_len = 0x7fffffff & MIN(TARGET_PAGE_MASK, PAGE_MASK);
 149     total_len = 0;
 150
 151     for (i = 0; i < count; i++) {
 152         abi_ulong base = tswapal(target_vec[i].iov_base);
 153         abi_long len = tswapal(target_vec[i].iov_len);
 154
 155         if (len < 0) {
 156             err = EINVAL;
 157             goto fail;
 158         } else if (len == 0) {
 159             /* Zero length pointer is ignored. */
 160             vec[i].iov_base = 0;
 161         } else {
 162             vec[i].iov_base = lock_user(type, base, len, copy);
 163             /*
 164              * If the first buffer pointer is bad, this is a fault.  But
 165              * subsequent bad buffers will result in a partial write; this is
 166              * realized by filling the vector with null pointers and zero
 167              * lengths.
 168              */
 169             if (!vec[i].iov_base) {
 170                 if (i == 0) {
 171                     err = EFAULT;
 172                     goto fail;
 173                 } else {
 174                     /*
 175                      * Fail all the subsequent addresses, they are already
 176                      * zero'd.
 177                      */
 178                     goto out;
 179                 }
 180             }
 181             if (len > max_len - total_len) {
 182                 len = max_len - total_len;
 183             }
 184         }
 185         vec[i].iov_len = len;
 186         total_len += len;
 187     }
 188 out:
 189     unlock_user(target_vec, target_addr, 0);
 190     return vec;
 191
 192 fail:
 193     helper_unlock_iovec(target_vec, target_addr, vec, i, copy);
 194 fail2:
 195     g_free(vec);
 196     errno = err;
 197     return NULL;
 198 }
 199
 200 void unlock_iovec(struct iovec *vec, abi_ulong target_addr,
 201         int count, int copy)
 202 {
 203     struct target_iovec *target_vec;
 204
 205     target_vec = lock_user(VERIFY_READ, target_addr,
 206                            count * sizeof(struct target_iovec), 1);
 207     if (target_vec) {
 208         helper_unlock_iovec(target_vec, target_addr, vec, count, copy);
 209     }
 210
 211     g_free(vec);
 212 }
 213
 214 /*
 215  * All errnos that freebsd_syscall() returns must be -TARGET_<errcode>.
 216  */
 217 static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 218                                 abi_long arg2, abi_long arg3, abi_long arg4,
 219                                 abi_long arg5, abi_long arg6, abi_long arg7,
 220                                 abi_long arg8)
 221 {
 222     abi_long ret;
 223
 224     switch (num) {
 225         /*
 226          * process system calls
 227          */
 228     case TARGET_FREEBSD_NR_exit: /* exit(2) */
 229         ret = do_bsd_exit(cpu_env, arg1);
 230         break;
 231
 232         /*
 233          * File system calls.
 234          */
 235     case TARGET_FREEBSD_NR_read: /* read(2) */
 236         ret = do_bsd_read(arg1, arg2, arg3);
 237         break;
 238
 239     case TARGET_FREEBSD_NR_pread: /* pread(2) */
 240         ret = do_bsd_pread(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
 241         break;
 242
 243     case TARGET_FREEBSD_NR_readv: /* readv(2) */
 244         ret = do_bsd_readv(arg1, arg2, arg3);
 245         break;
 246
 247     case TARGET_FREEBSD_NR_preadv: /* preadv(2) */
 248         ret = do_bsd_preadv(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
 249
 250     case TARGET_FREEBSD_NR_write: /* write(2) */
 251         ret = do_bsd_write(arg1, arg2, arg3);
 252         break;
 253
 254     case TARGET_FREEBSD_NR_pwrite: /* pwrite(2) */
 255         ret = do_bsd_pwrite(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
 256         break;
 257
 258     case TARGET_FREEBSD_NR_writev: /* writev(2) */
 259         ret = do_bsd_writev(arg1, arg2, arg3);
 260         break;
 261
 262     case TARGET_FREEBSD_NR_pwritev: /* pwritev(2) */
 263         ret = do_bsd_pwritev(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
 264         break;
 265
 266     case TARGET_FREEBSD_NR_open: /* open(2) */
 267         ret = do_bsd_open(arg1, arg2, arg3);
 268         break;
 269
 270     case TARGET_FREEBSD_NR_openat: /* openat(2) */
 271         ret = do_bsd_openat(arg1, arg2, arg3, arg4);
 272         break;
 273
 274     case TARGET_FREEBSD_NR_close: /* close(2) */
 275         ret = do_bsd_close(arg1);
 276         break;
 277
 278     case TARGET_FREEBSD_NR_fdatasync: /* fdatasync(2) */
 279         ret = do_bsd_fdatasync(arg1);
 280         break;
 281
 282     case TARGET_FREEBSD_NR_fsync: /* fsync(2) */
 283         ret = do_bsd_fsync(arg1);
 284         break;
 285
 286     case TARGET_FREEBSD_NR_freebsd12_closefrom: /* closefrom(2) */
 287         ret = do_bsd_closefrom(arg1);
 288         break;
 289
 290     case TARGET_FREEBSD_NR_revoke: /* revoke(2) */
 291         ret = do_bsd_revoke(arg1);
 292         break;
 293
 294     case TARGET_FREEBSD_NR_access: /* access(2) */
 295         ret = do_bsd_access(arg1, arg2);
 296         break;
 297
 298     case TARGET_FREEBSD_NR_eaccess: /* eaccess(2) */
 299         ret = do_bsd_eaccess(arg1, arg2);
 300         break;
 301
 302     case TARGET_FREEBSD_NR_faccessat: /* faccessat(2) */
 303         ret = do_bsd_faccessat(arg1, arg2, arg3, arg4);
 304         break;
 305
 306     case TARGET_FREEBSD_NR_chdir: /* chdir(2) */
 307         ret = do_bsd_chdir(arg1);
 308         break;
 309
 310     case TARGET_FREEBSD_NR_fchdir: /* fchdir(2) */
 311         ret = do_bsd_fchdir(arg1);
 312         break;
 313
 314     case TARGET_FREEBSD_NR_rename: /* rename(2) */
 315         ret = do_bsd_rename(arg1, arg2);
 316         break;
 317
 318     case TARGET_FREEBSD_NR_renameat: /* renameat(2) */
 319         ret = do_bsd_renameat(arg1, arg2, arg3, arg4);
 320         break;
 321
 322     case TARGET_FREEBSD_NR_link: /* link(2) */
 323         ret = do_bsd_link(arg1, arg2);
 324         break;
 325
 326     case TARGET_FREEBSD_NR_linkat: /* linkat(2) */
 327         ret = do_bsd_linkat(arg1, arg2, arg3, arg4, arg5);
 328         break;
 329
 330     case TARGET_FREEBSD_NR_unlink: /* unlink(2) */
 331         ret = do_bsd_unlink(arg1);
 332         break;
 333
 334     case TARGET_FREEBSD_NR_unlinkat: /* unlinkat(2) */
 335         ret = do_bsd_unlinkat(arg1, arg2, arg3);
 336         break;
 337
 338     case TARGET_FREEBSD_NR_mkdir: /* mkdir(2) */
 339         ret = do_bsd_mkdir(arg1, arg2);
 340         break;
 341
 342     case TARGET_FREEBSD_NR_mkdirat: /* mkdirat(2) */
 343         ret = do_bsd_mkdirat(arg1, arg2, arg3);
 344         break;
 345
 346     case TARGET_FREEBSD_NR_rmdir: /* rmdir(2) (XXX no rmdirat()?) */
 347         ret = do_bsd_rmdir(arg1);
 348         break;
 349
 350     case TARGET_FREEBSD_NR___getcwd: /* undocumented __getcwd() */
 351         ret = do_bsd___getcwd(arg1, arg2);
 352         break;
 353
 354     case TARGET_FREEBSD_NR_dup: /* dup(2) */
 355         ret = do_bsd_dup(arg1);
 356         break;
 357
 358     case TARGET_FREEBSD_NR_dup2: /* dup2(2) */
 359         ret = do_bsd_dup2(arg1, arg2);
 360         break;
 361
 362     case TARGET_FREEBSD_NR_truncate: /* truncate(2) */
 363         ret = do_bsd_truncate(cpu_env, arg1, arg2, arg3, arg4);
 364         break;
 365
 366     case TARGET_FREEBSD_NR_ftruncate: /* ftruncate(2) */
 367         ret = do_bsd_ftruncate(cpu_env, arg1, arg2, arg3, arg4);
 368         break;
 369
 370     case TARGET_FREEBSD_NR_acct: /* acct(2) */
 371         ret = do_bsd_acct(arg1);
 372         break;
 373
 374     case TARGET_FREEBSD_NR_sync: /* sync(2) */
 375         ret = do_bsd_sync();
 376         break;
 377
 378     case TARGET_FREEBSD_NR_mount: /* mount(2) */
 379         ret = do_bsd_mount(arg1, arg2, arg3, arg4);
 380         break;
 381
 382     case TARGET_FREEBSD_NR_unmount: /* unmount(2) */
 383         ret = do_bsd_unmount(arg1, arg2);
 384         break;
 385
 386     case TARGET_FREEBSD_NR_nmount: /* nmount(2) */
 387         ret = do_bsd_nmount(arg1, arg2, arg3);
 388         break;
 389
 390     case TARGET_FREEBSD_NR_symlink: /* symlink(2) */
 391         ret = do_bsd_symlink(arg1, arg2);
 392         break;
 393
 394     case TARGET_FREEBSD_NR_symlinkat: /* symlinkat(2) */
 395         ret = do_bsd_symlinkat(arg1, arg2, arg3);
 396         break;
 397
 398     case TARGET_FREEBSD_NR_readlink: /* readlink(2) */
 399         ret = do_bsd_readlink(cpu_env, arg1, arg2, arg3);
 400         break;
 401
 402     case TARGET_FREEBSD_NR_readlinkat: /* readlinkat(2) */
 403         ret = do_bsd_readlinkat(arg1, arg2, arg3, arg4);
 404         break;
 405
 406     case TARGET_FREEBSD_NR_chmod: /* chmod(2) */
 407         ret = do_bsd_chmod(arg1, arg2);
 408         break;
 409
 410     case TARGET_FREEBSD_NR_fchmod: /* fchmod(2) */
 411         ret = do_bsd_fchmod(arg1, arg2);
 412         break;
 413
 414     case TARGET_FREEBSD_NR_lchmod: /* lchmod(2) */
 415         ret = do_bsd_lchmod(arg1, arg2);
 416         break;
 417
 418     case TARGET_FREEBSD_NR_fchmodat: /* fchmodat(2) */
 419         ret = do_bsd_fchmodat(arg1, arg2, arg3, arg4);
 420         break;
 421
 422     case TARGET_FREEBSD_NR_freebsd11_mknod: /* mknod(2) */
 423         ret = do_bsd_freebsd11_mknod(arg1, arg2, arg3);
 424         break;
 425
 426     case TARGET_FREEBSD_NR_freebsd11_mknodat: /* mknodat(2) */
 427         ret = do_bsd_freebsd11_mknodat(arg1, arg2, arg3, arg4);
 428         break;
 429
 430     case TARGET_FREEBSD_NR_mknodat: /* mknodat(2) */
 431         ret = do_bsd_mknodat(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
 432         break;
 433
 434     case TARGET_FREEBSD_NR_chown: /* chown(2) */
 435         ret = do_bsd_chown(arg1, arg2, arg3);
 436         break;
 437
 438     case TARGET_FREEBSD_NR_fchown: /* fchown(2) */
 439         ret = do_bsd_fchown(arg1, arg2, arg3);
 440         break;
 441
 442     case TARGET_FREEBSD_NR_lchown: /* lchown(2) */
 443         ret = do_bsd_lchown(arg1, arg2, arg3);
 444         break;
 445
 446     case TARGET_FREEBSD_NR_fchownat: /* fchownat(2) */
 447         ret = do_bsd_fchownat(arg1, arg2, arg3, arg4, arg5);
 448         break;
 449
 450     case TARGET_FREEBSD_NR_chflags: /* chflags(2) */
 451         ret = do_bsd_chflags(arg1, arg2);
 452         break;
 453
 454     case TARGET_FREEBSD_NR_lchflags: /* lchflags(2) */
 455         ret = do_bsd_lchflags(arg1, arg2);
 456         break;
 457
 458     case TARGET_FREEBSD_NR_fchflags: /* fchflags(2) */
 459         ret = do_bsd_fchflags(arg1, arg2);
 460         break;
 461
 462     case TARGET_FREEBSD_NR_chroot: /* chroot(2) */
 463         ret = do_bsd_chroot(arg1);
 464         break;
 465
 466     case TARGET_FREEBSD_NR_flock: /* flock(2) */
 467         ret = do_bsd_flock(arg1, arg2);
 468         break;
 469
 470     case TARGET_FREEBSD_NR_mkfifo: /* mkfifo(2) */
 471         ret = do_bsd_mkfifo(arg1, arg2);
 472         break;
 473
 474     case TARGET_FREEBSD_NR_mkfifoat: /* mkfifoat(2) */
 475         ret = do_bsd_mkfifoat(arg1, arg2, arg3);
 476         break;
 477
 478     case TARGET_FREEBSD_NR_pathconf: /* pathconf(2) */
 479         ret = do_bsd_pathconf(arg1, arg2);
 480         break;
 481
 482     case TARGET_FREEBSD_NR_lpathconf: /* lpathconf(2) */
 483         ret = do_bsd_lpathconf(arg1, arg2);
 484         break;
 485
 486     case TARGET_FREEBSD_NR_fpathconf: /* fpathconf(2) */
 487         ret = do_bsd_fpathconf(arg1, arg2);
 488         break;
 489
 490     case TARGET_FREEBSD_NR_undelete: /* undelete(2) */
 491         ret = do_bsd_undelete(arg1);
 492         break;
 493
 494     default:
 495         qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num);
 496         ret = -TARGET_ENOSYS;
 497         break;
 498     }
 499
 500     return ret;
 501 }
 502
 503 /*
 504  * do_freebsd_syscall() should always have a single exit point at the end so
 505  * that actions, such as logging of syscall results, can be performed. This
 506  * as a wrapper around freebsd_syscall() so that actually happens. Since
 507  * that is a singleton, modern compilers will inline it anyway...
 508  */
 509 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 510                             abi_long arg2, abi_long arg3, abi_long arg4,
 511                             abi_long arg5, abi_long arg6, abi_long arg7,
 512                             abi_long arg8)
 513 {
 514     CPUState *cpu = env_cpu(cpu_env);
 515     int ret;
 516
 517     trace_guest_user_syscall(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8);
 518     if (do_strace) {
 519         print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 520     }
 521
 522     ret = freebsd_syscall(cpu_env, num, arg1, arg2, arg3, arg4, arg5, arg6,
 523                           arg7, arg8);
 524     if (do_strace) {
 525         print_freebsd_syscall_ret(num, ret);
 526     }
 527     trace_guest_user_syscall_ret(cpu, num, ret);
 528
 529     return ret;
 530 }
 531
 532 void syscall_init(void)
 533 {
 534 }