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         break;
 203     case CTLTYPE_ULONG:
 204         *(uint64_t *)holdp = tswap64(*(unsigned long *)holdp);
 205         break;
 206 #endif
 207 #ifdef CTLTYPE_U64
 208     case CTLTYPE_S64:
 209     case CTLTYPE_U64:
 210 #else
 211     case CTLTYPE_QUAD:
 212 #endif
 213         *(uint64_t *)holdp = tswap64(*(uint64_t *)holdp);
 214         break;
 215     case CTLTYPE_STRING:
 216         break;
 217     default:
 218         /* XXX unhandled */
 219         return -1;
 220     }
 221     return 0;
 222 }
 223
 224 /* XXX this needs to be emulated on non-FreeBSD hosts... */
 225 static abi_long do_freebsd_sysctl(abi_ulong namep, int32_t namelen, abi_ulong oldp,
 226                           abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen)
 227 {
 228     abi_long ret;
 229     void *hnamep, *holdp, *hnewp = NULL;
 230     size_t holdlen;
 231     abi_ulong oldlen = 0;
 232     int32_t *snamep = g_malloc(sizeof(int32_t) * namelen), *p, *q, i;
 233     uint32_t kind = 0;
 234
 235     if (oldlenp)
 236         get_user_ual(oldlen, oldlenp);
 237     if (!(hnamep = lock_user(VERIFY_READ, namep, namelen, 1)))
 238         return -TARGET_EFAULT;
 239     if (newp && !(hnewp = lock_user(VERIFY_READ, newp, newlen, 1)))
 240         return -TARGET_EFAULT;
 241     if (!(holdp = lock_user(VERIFY_WRITE, oldp, oldlen, 0)))
 242         return -TARGET_EFAULT;
 243     holdlen = oldlen;
 244     for (p = hnamep, q = snamep, i = 0; i < namelen; p++, i++)
 245        *q++ = tswap32(*p);
 246     oidfmt(snamep, namelen, NULL, &kind);
 247     /* XXX swap hnewp */
 248     ret = get_errno(sysctl(snamep, namelen, holdp, &holdlen, hnewp, newlen));
 249     if (!ret)
 250         sysctl_oldcvt(holdp, holdlen, kind);
 251     put_user_ual(holdlen, oldlenp);
 252     unlock_user(hnamep, namep, 0);
 253     unlock_user(holdp, oldp, holdlen);
 254     if (hnewp)
 255         unlock_user(hnewp, newp, 0);
 256     g_free(snamep);
 257     return ret;
 258 }
 259 #endif
 260
 261 /* FIXME
 262  * lock_iovec()/unlock_iovec() have a return code of 0 for success where
 263  * other lock functions have a return code of 0 for failure.
 264  */
 265 static abi_long lock_iovec(int type, struct iovec *vec, abi_ulong target_addr,
 266                            int count, int copy)
 267 {
 268     struct target_iovec *target_vec;
 269     abi_ulong base;
 270     int i;
 271
 272     target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 273     if (!target_vec)
 274         return -TARGET_EFAULT;
 275     for (i = 0;i < count; i++) {
 276         base = tswapl(target_vec[i].iov_base);
 277         vec[i].iov_len = tswapl(target_vec[i].iov_len);
 278         if (vec[i].iov_len != 0) {
 279             vec[i].iov_base = lock_user(type, base, vec[i].iov_len, copy);
 280             /* Don't check lock_user return value. We must call writev even
 281                if a element has invalid base address. */
 282         } else {
 283             /* zero length pointer is ignored */
 284             vec[i].iov_base = NULL;
 285         }
 286     }
 287     unlock_user (target_vec, target_addr, 0);
 288     return 0;
 289 }
 290
 291 static abi_long unlock_iovec(struct iovec *vec, abi_ulong target_addr,
 292                              int count, int copy)
 293 {
 294     struct target_iovec *target_vec;
 295     abi_ulong base;
 296     int i;
 297
 298     target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 299     if (!target_vec)
 300         return -TARGET_EFAULT;
 301     for (i = 0;i < count; i++) {
 302         if (target_vec[i].iov_base) {
 303             base = tswapl(target_vec[i].iov_base);
 304             unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0);
 305         }
 306     }
 307     unlock_user (target_vec, target_addr, 0);
 308
 309     return 0;
 310 }
 311
 312 /* do_syscall() should always have a single exit point at the end so
 313    that actions, such as logging of syscall results, can be performed.
 314    All errnos that do_syscall() returns must be -TARGET_<errcode>. */
 315 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 316                             abi_long arg2, abi_long arg3, abi_long arg4,
 317                             abi_long arg5, abi_long arg6, abi_long arg7,
 318                             abi_long arg8)
 319 {
 320     CPUState *cpu = env_cpu(cpu_env);
 321     abi_long ret;
 322     void *p;
 323
 324 #ifdef DEBUG
 325     gemu_log("freebsd syscall %d\n", num);
 326 #endif
 327     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 328
 329     if (do_strace)
 330         print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 331
 332     switch (num) {
 333     case TARGET_FREEBSD_NR_exit:
 334 #ifdef CONFIG_GPROF
 335         _mcleanup();
 336 #endif
 337         gdb_exit(arg1);
 338         qemu_plugin_atexit_cb();
 339         /* XXX: should free thread stack and CPU env */
 340         _exit(arg1);
 341         ret = 0; /* avoid warning */
 342         break;
 343     case TARGET_FREEBSD_NR_read:
 344         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 345             goto efault;
 346         ret = get_errno(read(arg1, p, arg3));
 347         unlock_user(p, arg2, ret);
 348         break;
 349     case TARGET_FREEBSD_NR_write:
 350         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 351             goto efault;
 352         ret = get_errno(write(arg1, p, arg3));
 353         unlock_user(p, arg2, 0);
 354         break;
 355     case TARGET_FREEBSD_NR_writev:
 356         {
 357             int count = arg3;
 358             struct iovec *vec;
 359
 360             vec = alloca(count * sizeof(struct iovec));
 361             if (lock_iovec(VERIFY_READ, vec, arg2, count, 1) < 0)
 362                 goto efault;
 363             ret = get_errno(writev(arg1, vec, count));
 364             unlock_iovec(vec, arg2, count, 0);
 365         }
 366         break;
 367     case TARGET_FREEBSD_NR_open:
 368         if (!(p = lock_user_string(arg1)))
 369             goto efault;
 370         ret = get_errno(open(path(p),
 371                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 372                              arg3));
 373         unlock_user(p, arg1, 0);
 374         break;
 375     case TARGET_FREEBSD_NR_mmap:
 376         ret = get_errno(target_mmap(arg1, arg2, arg3,
 377                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 378                                     arg5,
 379                                     arg6));
 380         break;
 381     case TARGET_FREEBSD_NR_mprotect:
 382         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 383         break;
 384     case TARGET_FREEBSD_NR_break:
 385         ret = do_obreak(arg1);
 386         break;
 387 #ifdef __FreeBSD__
 388     case TARGET_FREEBSD_NR___sysctl:
 389         ret = do_freebsd_sysctl(arg1, arg2, arg3, arg4, arg5, arg6);
 390         break;
 391 #endif
 392     case TARGET_FREEBSD_NR_sysarch:
 393         ret = do_freebsd_sysarch(cpu_env, arg1, arg2);
 394         break;
 395     case TARGET_FREEBSD_NR_syscall:
 396     case TARGET_FREEBSD_NR___syscall:
 397         ret = do_freebsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,arg7,arg8,0);
 398         break;
 399     default:
 400         ret = get_errno(syscall(num, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8));
 401         break;
 402     }
 403  fail:
 404 #ifdef DEBUG
 405     gemu_log(" = %ld\n", ret);
 406 #endif
 407     if (do_strace)
 408         print_freebsd_syscall_ret(num, ret);
 409
 410     record_syscall_return(cpu, num, ret);
 411     return ret;
 412  efault:
 413     ret = -TARGET_EFAULT;
 414     goto fail;
 415 }
 416
 417 abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
 418                            abi_long arg2, abi_long arg3, abi_long arg4,
 419                            abi_long arg5, abi_long arg6)
 420 {
 421     CPUState *cpu = env_cpu(cpu_env);
 422     abi_long ret;
 423     void *p;
 424
 425 #ifdef DEBUG
 426     gemu_log("netbsd syscall %d\n", num);
 427 #endif
 428
 429     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 430
 431     if (do_strace)
 432         print_netbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 433
 434     switch (num) {
 435     case TARGET_NETBSD_NR_exit:
 436 #ifdef CONFIG_GPROF
 437         _mcleanup();
 438 #endif
 439         gdb_exit(arg1);
 440         qemu_plugin_atexit_cb();
 441         /* XXX: should free thread stack and CPU env */
 442         _exit(arg1);
 443         ret = 0; /* avoid warning */
 444         break;
 445     case TARGET_NETBSD_NR_read:
 446         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 447             goto efault;
 448         ret = get_errno(read(arg1, p, arg3));
 449         unlock_user(p, arg2, ret);
 450         break;
 451     case TARGET_NETBSD_NR_write:
 452         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 453             goto efault;
 454         ret = get_errno(write(arg1, p, arg3));
 455         unlock_user(p, arg2, 0);
 456         break;
 457     case TARGET_NETBSD_NR_open:
 458         if (!(p = lock_user_string(arg1)))
 459             goto efault;
 460         ret = get_errno(open(path(p),
 461                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 462                              arg3));
 463         unlock_user(p, arg1, 0);
 464         break;
 465     case TARGET_NETBSD_NR_mmap:
 466         ret = get_errno(target_mmap(arg1, arg2, arg3,
 467                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 468                                     arg5,
 469                                     arg6));
 470         break;
 471     case TARGET_NETBSD_NR_mprotect:
 472         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 473         break;
 474     case TARGET_NETBSD_NR_syscall:
 475     case TARGET_NETBSD_NR___syscall:
 476         ret = do_netbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 477         break;
 478     default:
 479         ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 480         break;
 481     }
 482  fail:
 483 #ifdef DEBUG
 484     gemu_log(" = %ld\n", ret);
 485 #endif
 486     if (do_strace)
 487         print_netbsd_syscall_ret(num, ret);
 488
 489     record_syscall_return(cpu, num, ret);
 490     return ret;
 491  efault:
 492     ret = -TARGET_EFAULT;
 493     goto fail;
 494 }
 495
 496 abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
 497                             abi_long arg2, abi_long arg3, abi_long arg4,
 498                             abi_long arg5, abi_long arg6)
 499 {
 500     CPUState *cpu = env_cpu(cpu_env);
 501     abi_long ret;
 502     void *p;
 503
 504 #ifdef DEBUG
 505     gemu_log("openbsd syscall %d\n", num);
 506 #endif
 507
 508     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 509
 510     if (do_strace)
 511         print_openbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 512
 513     switch (num) {
 514     case TARGET_OPENBSD_NR_exit:
 515 #ifdef CONFIG_GPROF
 516         _mcleanup();
 517 #endif
 518         gdb_exit(arg1);
 519         qemu_plugin_atexit_cb();
 520         /* XXX: should free thread stack and CPU env */
 521         _exit(arg1);
 522         ret = 0; /* avoid warning */
 523         break;
 524     case TARGET_OPENBSD_NR_read:
 525         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 526             goto efault;
 527         ret = get_errno(read(arg1, p, arg3));
 528         unlock_user(p, arg2, ret);
 529         break;
 530     case TARGET_OPENBSD_NR_write:
 531         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 532             goto efault;
 533         ret = get_errno(write(arg1, p, arg3));
 534         unlock_user(p, arg2, 0);
 535         break;
 536     case TARGET_OPENBSD_NR_open:
 537         if (!(p = lock_user_string(arg1)))
 538             goto efault;
 539         ret = get_errno(open(path(p),
 540                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 541                              arg3));
 542         unlock_user(p, arg1, 0);
 543         break;
 544     case TARGET_OPENBSD_NR_mmap:
 545         ret = get_errno(target_mmap(arg1, arg2, arg3,
 546                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 547                                     arg5,
 548                                     arg6));
 549         break;
 550     case TARGET_OPENBSD_NR_mprotect:
 551         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 552         break;
 553     case TARGET_OPENBSD_NR_syscall:
 554     case TARGET_OPENBSD_NR___syscall:
 555         ret = do_openbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 556         break;
 557     default:
 558         ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 559         break;
 560     }
 561  fail:
 562 #ifdef DEBUG
 563     gemu_log(" = %ld\n", ret);
 564 #endif
 565     if (do_strace)
 566         print_openbsd_syscall_ret(num, ret);
 567
 568     record_syscall_return(cpu, num, ret);
 569     return ret;
 570  efault:
 571     ret = -TARGET_EFAULT;
 572     goto fail;
 573 }
 574
 575 void syscall_init(void)
 576 {
 577 }