bsd-user/syscall.c

   1 /*
   2  *  BSD syscalls
   3  *
   4  *  Copyright (c) 2003 - 2008 Fabrice Bellard
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #include "qemu/osdep.h"
  20 #include "qemu/cutils.h"
  21 #include "qemu/path.h"
  22 #include <sys/syscall.h>
  23 #include <sys/param.h>
  24 #include <sys/sysctl.h>
  25 #include <utime.h>
  26
  27 #include "qemu.h"
  28 #include "qemu-common.h"
  29 #include "user/syscall-trace.h"
  30
  31 //#define DEBUG
  32
  33 static abi_ulong target_brk;
  34 static abi_ulong target_original_brk;
  35
  36 static inline abi_long get_errno(abi_long ret)
  37 {
  38     if (ret == -1)
  39         /* XXX need to translate host -> target errnos here */
  40         return -(errno);
  41     else
  42         return ret;
  43 }
  44
  45 #define target_to_host_bitmask(x, tbl) (x)
  46
  47 static inline int is_error(abi_long ret)
  48 {
  49     return (abi_ulong)ret >= (abi_ulong)(-4096);
  50 }
  51
  52 void target_set_brk(abi_ulong new_brk)
  53 {
  54     target_original_brk = target_brk = HOST_PAGE_ALIGN(new_brk);
  55 }
  56
  57 /* do_obreak() must return target errnos. */
  58 static abi_long do_obreak(abi_ulong new_brk)
  59 {
  60     abi_ulong brk_page;
  61     abi_long mapped_addr;
  62     int new_alloc_size;
  63
  64     if (!new_brk)
  65         return 0;
  66     if (new_brk < target_original_brk)
  67         return -TARGET_EINVAL;
  68
  69     brk_page = HOST_PAGE_ALIGN(target_brk);
  70
  71     /* If the new brk is less than this, set it and we're done... */
  72     if (new_brk < brk_page) {
  73         target_brk = new_brk;
  74         return 0;
  75     }
  76
  77     /* We need to allocate more memory after the brk... */
  78     new_alloc_size = HOST_PAGE_ALIGN(new_brk - brk_page + 1);
  79     mapped_addr = get_errno(target_mmap(brk_page, new_alloc_size,
  80                                         PROT_READ|PROT_WRITE,
  81                                         MAP_ANON|MAP_FIXED|MAP_PRIVATE, -1, 0));
  82
  83     if (!is_error(mapped_addr))
  84         target_brk = new_brk;
  85     else
  86         return mapped_addr;
  87
  88     return 0;
  89 }
  90
  91 #if defined(TARGET_I386)
  92 static abi_long do_freebsd_sysarch(CPUX86State *env, int op, abi_ulong parms)
  93 {
  94     abi_long ret = 0;
  95     abi_ulong val;
  96     int idx;
  97
  98     switch(op) {
  99 #ifdef TARGET_ABI32
 100     case TARGET_FREEBSD_I386_SET_GSBASE:
 101     case TARGET_FREEBSD_I386_SET_FSBASE:
 102         if (op == TARGET_FREEBSD_I386_SET_GSBASE)
 103 #else
 104     case TARGET_FREEBSD_AMD64_SET_GSBASE:
 105     case TARGET_FREEBSD_AMD64_SET_FSBASE:
 106         if (op == TARGET_FREEBSD_AMD64_SET_GSBASE)
 107 #endif
 108             idx = R_GS;
 109         else
 110             idx = R_FS;
 111         if (get_user(val, parms, abi_ulong))
 112             return -TARGET_EFAULT;
 113         cpu_x86_load_seg(env, idx, 0);
 114         env->segs[idx].base = val;
 115         break;
 116 #ifdef TARGET_ABI32
 117     case TARGET_FREEBSD_I386_GET_GSBASE:
 118     case TARGET_FREEBSD_I386_GET_FSBASE:
 119         if (op == TARGET_FREEBSD_I386_GET_GSBASE)
 120 #else
 121     case TARGET_FREEBSD_AMD64_GET_GSBASE:
 122     case TARGET_FREEBSD_AMD64_GET_FSBASE:
 123         if (op == TARGET_FREEBSD_AMD64_GET_GSBASE)
 124 #endif
 125             idx = R_GS;
 126         else
 127             idx = R_FS;
 128         val = env->segs[idx].base;
 129         if (put_user(val, parms, abi_ulong))
 130             return -TARGET_EFAULT;
 131         break;
 132     /* XXX handle the others... */
 133     default:
 134         ret = -TARGET_EINVAL;
 135         break;
 136     }
 137     return ret;
 138 }
 139 #endif
 140
 141 #ifdef TARGET_SPARC
 142 static abi_long do_freebsd_sysarch(void *env, int op, abi_ulong parms)
 143 {
 144     /* XXX handle
 145      * TARGET_FREEBSD_SPARC_UTRAP_INSTALL,
 146      * TARGET_FREEBSD_SPARC_SIGTRAMP_INSTALL
 147      */
 148     return -TARGET_EINVAL;
 149 }
 150 #endif
 151
 152 #ifdef __FreeBSD__
 153 /*
 154  * XXX this uses the undocumented oidfmt interface to find the kind of
 155  * a requested sysctl, see /sys/kern/kern_sysctl.c:sysctl_sysctl_oidfmt()
 156  * (this is mostly copied from src/sbin/sysctl/sysctl.c)
 157  */
 158 static int
 159 oidfmt(int *oid, int len, char *fmt, uint32_t *kind)
 160 {
 161     int qoid[CTL_MAXNAME+2];
 162     uint8_t buf[BUFSIZ];
 163     int i;
 164     size_t j;
 165
 166     qoid[0] = 0;
 167     qoid[1] = 4;
 168     memcpy(qoid + 2, oid, len * sizeof(int));
 169
 170     j = sizeof(buf);
 171     i = sysctl(qoid, len + 2, buf, &j, 0, 0);
 172     if (i)
 173         return i;
 174
 175     if (kind)
 176         *kind = *(uint32_t *)buf;
 177
 178     if (fmt)
 179         strcpy(fmt, (char *)(buf + sizeof(uint32_t)));
 180     return (0);
 181 }
 182
 183 /*
 184  * try and convert sysctl return data for the target.
 185  * XXX doesn't handle CTLTYPE_OPAQUE and CTLTYPE_STRUCT.
 186  */
 187 static int sysctl_oldcvt(void *holdp, size_t holdlen, uint32_t kind)
 188 {
 189     switch (kind & CTLTYPE) {
 190     case CTLTYPE_INT:
 191     case CTLTYPE_UINT:
 192         *(uint32_t *)holdp = tswap32(*(uint32_t *)holdp);
 193         break;
 194 #ifdef TARGET_ABI32
 195     case CTLTYPE_LONG:
 196     case CTLTYPE_ULONG:
 197         *(uint32_t *)holdp = tswap32(*(long *)holdp);
 198         break;
 199 #else
 200     case CTLTYPE_LONG:
 201         *(uint64_t *)holdp = tswap64(*(long *)holdp);
 202     case CTLTYPE_ULONG:
 203         *(uint64_t *)holdp = tswap64(*(unsigned long *)holdp);
 204         break;
 205 #endif
 206 #ifdef CTLTYPE_U64
 207     case CTLTYPE_S64:
 208     case CTLTYPE_U64:
 209 #else
 210     case CTLTYPE_QUAD:
 211 #endif
 212         *(uint64_t *)holdp = tswap64(*(uint64_t *)holdp);
 213         break;
 214     case CTLTYPE_STRING:
 215         break;
 216     default:
 217         /* XXX unhandled */
 218         return -1;
 219     }
 220     return 0;
 221 }
 222
 223 /* XXX this needs to be emulated on non-FreeBSD hosts... */
 224 static abi_long do_freebsd_sysctl(abi_ulong namep, int32_t namelen, abi_ulong oldp,
 225                           abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen)
 226 {
 227     abi_long ret;
 228     void *hnamep, *holdp, *hnewp = NULL;
 229     size_t holdlen;
 230     abi_ulong oldlen = 0;
 231     int32_t *snamep = g_malloc(sizeof(int32_t) * namelen), *p, *q, i;
 232     uint32_t kind = 0;
 233
 234     if (oldlenp)
 235         get_user_ual(oldlen, oldlenp);
 236     if (!(hnamep = lock_user(VERIFY_READ, namep, namelen, 1)))
 237         return -TARGET_EFAULT;
 238     if (newp && !(hnewp = lock_user(VERIFY_READ, newp, newlen, 1)))
 239         return -TARGET_EFAULT;
 240     if (!(holdp = lock_user(VERIFY_WRITE, oldp, oldlen, 0)))
 241         return -TARGET_EFAULT;
 242     holdlen = oldlen;
 243     for (p = hnamep, q = snamep, i = 0; i < namelen; p++, i++)
 244        *q++ = tswap32(*p);
 245     oidfmt(snamep, namelen, NULL, &kind);
 246     /* XXX swap hnewp */
 247     ret = get_errno(sysctl(snamep, namelen, holdp, &holdlen, hnewp, newlen));
 248     if (!ret)
 249         sysctl_oldcvt(holdp, holdlen, kind);
 250     put_user_ual(holdlen, oldlenp);
 251     unlock_user(hnamep, namep, 0);
 252     unlock_user(holdp, oldp, holdlen);
 253     if (hnewp)
 254         unlock_user(hnewp, newp, 0);
 255     g_free(snamep);
 256     return ret;
 257 }
 258 #endif
 259
 260 /* FIXME
 261  * lock_iovec()/unlock_iovec() have a return code of 0 for success where
 262  * other lock functions have a return code of 0 for failure.
 263  */
 264 static abi_long lock_iovec(int type, struct iovec *vec, abi_ulong target_addr,
 265                            int count, int copy)
 266 {
 267     struct target_iovec *target_vec;
 268     abi_ulong base;
 269     int i;
 270
 271     target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 272     if (!target_vec)
 273         return -TARGET_EFAULT;
 274     for(i = 0;i < count; i++) {
 275         base = tswapl(target_vec[i].iov_base);
 276         vec[i].iov_len = tswapl(target_vec[i].iov_len);
 277         if (vec[i].iov_len != 0) {
 278             vec[i].iov_base = lock_user(type, base, vec[i].iov_len, copy);
 279             /* Don't check lock_user return value. We must call writev even
 280                if a element has invalid base address. */
 281         } else {
 282             /* zero length pointer is ignored */
 283             vec[i].iov_base = NULL;
 284         }
 285     }
 286     unlock_user (target_vec, target_addr, 0);
 287     return 0;
 288 }
 289
 290 static abi_long unlock_iovec(struct iovec *vec, abi_ulong target_addr,
 291                              int count, int copy)
 292 {
 293     struct target_iovec *target_vec;
 294     abi_ulong base;
 295     int i;
 296
 297     target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 298     if (!target_vec)
 299         return -TARGET_EFAULT;
 300     for(i = 0;i < count; i++) {
 301         if (target_vec[i].iov_base) {
 302             base = tswapl(target_vec[i].iov_base);
 303             unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0);
 304         }
 305     }
 306     unlock_user (target_vec, target_addr, 0);
 307
 308     return 0;
 309 }
 310
 311 /* do_syscall() should always have a single exit point at the end so
 312    that actions, such as logging of syscall results, can be performed.
 313    All errnos that do_syscall() returns must be -TARGET_<errcode>. */
 314 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 315                             abi_long arg2, abi_long arg3, abi_long arg4,
 316                             abi_long arg5, abi_long arg6, abi_long arg7,
 317                             abi_long arg8)
 318 {
 319     CPUState *cpu = env_cpu(cpu_env);
 320     abi_long ret;
 321     void *p;
 322
 323 #ifdef DEBUG
 324     gemu_log("freebsd syscall %d\n", num);
 325 #endif
 326     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 327
 328     if(do_strace)
 329         print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 330
 331     switch(num) {
 332     case TARGET_FREEBSD_NR_exit:
 333 #ifdef CONFIG_GPROF
 334         _mcleanup();
 335 #endif
 336         gdb_exit(arg1);
 337         qemu_plugin_atexit_cb();
 338         /* XXX: should free thread stack and CPU env */
 339         _exit(arg1);
 340         ret = 0; /* avoid warning */
 341         break;
 342     case TARGET_FREEBSD_NR_read:
 343         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 344             goto efault;
 345         ret = get_errno(read(arg1, p, arg3));
 346         unlock_user(p, arg2, ret);
 347         break;
 348     case TARGET_FREEBSD_NR_write:
 349         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 350             goto efault;
 351         ret = get_errno(write(arg1, p, arg3));
 352         unlock_user(p, arg2, 0);
 353         break;
 354     case TARGET_FREEBSD_NR_writev:
 355         {
 356             int count = arg3;
 357             struct iovec *vec;
 358
 359             vec = alloca(count * sizeof(struct iovec));
 360             if (lock_iovec(VERIFY_READ, vec, arg2, count, 1) < 0)
 361                 goto efault;
 362             ret = get_errno(writev(arg1, vec, count));
 363             unlock_iovec(vec, arg2, count, 0);
 364         }
 365         break;
 366     case TARGET_FREEBSD_NR_open:
 367         if (!(p = lock_user_string(arg1)))
 368             goto efault;
 369         ret = get_errno(open(path(p),
 370                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 371                              arg3));
 372         unlock_user(p, arg1, 0);
 373         break;
 374     case TARGET_FREEBSD_NR_mmap:
 375         ret = get_errno(target_mmap(arg1, arg2, arg3,
 376                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 377                                     arg5,
 378                                     arg6));
 379         break;
 380     case TARGET_FREEBSD_NR_mprotect:
 381         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 382         break;
 383     case TARGET_FREEBSD_NR_break:
 384         ret = do_obreak(arg1);
 385         break;
 386 #ifdef __FreeBSD__
 387     case TARGET_FREEBSD_NR___sysctl:
 388         ret = do_freebsd_sysctl(arg1, arg2, arg3, arg4, arg5, arg6);
 389         break;
 390 #endif
 391     case TARGET_FREEBSD_NR_sysarch:
 392         ret = do_freebsd_sysarch(cpu_env, arg1, arg2);
 393         break;
 394     case TARGET_FREEBSD_NR_syscall:
 395     case TARGET_FREEBSD_NR___syscall:
 396         ret = do_freebsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,arg7,arg8,0);
 397         break;
 398     default:
 399         ret = get_errno(syscall(num, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8));
 400         break;
 401     }
 402  fail:
 403 #ifdef DEBUG
 404     gemu_log(" = %ld\n", ret);
 405 #endif
 406     if (do_strace)
 407         print_freebsd_syscall_ret(num, ret);
 408
 409     record_syscall_return(cpu, num, ret);
 410     return ret;
 411  efault:
 412     ret = -TARGET_EFAULT;
 413     goto fail;
 414 }
 415
 416 abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
 417                            abi_long arg2, abi_long arg3, abi_long arg4,
 418                            abi_long arg5, abi_long arg6)
 419 {
 420     CPUState *cpu = env_cpu(cpu_env);
 421     abi_long ret;
 422     void *p;
 423
 424 #ifdef DEBUG
 425     gemu_log("netbsd syscall %d\n", num);
 426 #endif
 427
 428     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 429
 430     if(do_strace)
 431         print_netbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 432
 433     switch(num) {
 434     case TARGET_NETBSD_NR_exit:
 435 #ifdef CONFIG_GPROF
 436         _mcleanup();
 437 #endif
 438         gdb_exit(arg1);
 439         qemu_plugin_atexit_cb();
 440         /* XXX: should free thread stack and CPU env */
 441         _exit(arg1);
 442         ret = 0; /* avoid warning */
 443         break;
 444     case TARGET_NETBSD_NR_read:
 445         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 446             goto efault;
 447         ret = get_errno(read(arg1, p, arg3));
 448         unlock_user(p, arg2, ret);
 449         break;
 450     case TARGET_NETBSD_NR_write:
 451         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 452             goto efault;
 453         ret = get_errno(write(arg1, p, arg3));
 454         unlock_user(p, arg2, 0);
 455         break;
 456     case TARGET_NETBSD_NR_open:
 457         if (!(p = lock_user_string(arg1)))
 458             goto efault;
 459         ret = get_errno(open(path(p),
 460                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 461                              arg3));
 462         unlock_user(p, arg1, 0);
 463         break;
 464     case TARGET_NETBSD_NR_mmap:
 465         ret = get_errno(target_mmap(arg1, arg2, arg3,
 466                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 467                                     arg5,
 468                                     arg6));
 469         break;
 470     case TARGET_NETBSD_NR_mprotect:
 471         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 472         break;
 473     case TARGET_NETBSD_NR_syscall:
 474     case TARGET_NETBSD_NR___syscall:
 475         ret = do_netbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 476         break;
 477     default:
 478         ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 479         break;
 480     }
 481  fail:
 482 #ifdef DEBUG
 483     gemu_log(" = %ld\n", ret);
 484 #endif
 485     if (do_strace)
 486         print_netbsd_syscall_ret(num, ret);
 487
 488     record_syscall_return(cpu, num, ret);
 489     return ret;
 490  efault:
 491     ret = -TARGET_EFAULT;
 492     goto fail;
 493 }
 494
 495 abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
 496                             abi_long arg2, abi_long arg3, abi_long arg4,
 497                             abi_long arg5, abi_long arg6)
 498 {
 499     CPUState *cpu = env_cpu(cpu_env);
 500     abi_long ret;
 501     void *p;
 502
 503 #ifdef DEBUG
 504     gemu_log("openbsd syscall %d\n", num);
 505 #endif
 506
 507     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 508
 509     if(do_strace)
 510         print_openbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 511
 512     switch(num) {
 513     case TARGET_OPENBSD_NR_exit:
 514 #ifdef CONFIG_GPROF
 515         _mcleanup();
 516 #endif
 517         gdb_exit(arg1);
 518         qemu_plugin_atexit_cb();
 519         /* XXX: should free thread stack and CPU env */
 520         _exit(arg1);
 521         ret = 0; /* avoid warning */
 522         break;
 523     case TARGET_OPENBSD_NR_read:
 524         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 525             goto efault;
 526         ret = get_errno(read(arg1, p, arg3));
 527         unlock_user(p, arg2, ret);
 528         break;
 529     case TARGET_OPENBSD_NR_write:
 530         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 531             goto efault;
 532         ret = get_errno(write(arg1, p, arg3));
 533         unlock_user(p, arg2, 0);
 534         break;
 535     case TARGET_OPENBSD_NR_open:
 536         if (!(p = lock_user_string(arg1)))
 537             goto efault;
 538         ret = get_errno(open(path(p),
 539                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 540                              arg3));
 541         unlock_user(p, arg1, 0);
 542         break;
 543     case TARGET_OPENBSD_NR_mmap:
 544         ret = get_errno(target_mmap(arg1, arg2, arg3,
 545                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 546                                     arg5,
 547                                     arg6));
 548         break;
 549     case TARGET_OPENBSD_NR_mprotect:
 550         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 551         break;
 552     case TARGET_OPENBSD_NR_syscall:
 553     case TARGET_OPENBSD_NR___syscall:
 554         ret = do_openbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 555         break;
 556     default:
 557         ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 558         break;
 559     }
 560  fail:
 561 #ifdef DEBUG
 562     gemu_log(" = %ld\n", ret);
 563 #endif
 564     if (do_strace)
 565         print_openbsd_syscall_ret(num, ret);
 566
 567     record_syscall_return(cpu, num, ret);
 568     return ret;
 569  efault:
 570     ret = -TARGET_EFAULT;
 571     goto fail;
 572 }
 573
 574 void syscall_init(void)
 575 {
 576 }