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 __FreeBSD__
 142 /*
 143  * XXX this uses the undocumented oidfmt interface to find the kind of
 144  * a requested sysctl, see /sys/kern/kern_sysctl.c:sysctl_sysctl_oidfmt()
 145  * (this is mostly copied from src/sbin/sysctl/sysctl.c)
 146  */
 147 static int
 148 oidfmt(int *oid, int len, char *fmt, uint32_t *kind)
 149 {
 150     int qoid[CTL_MAXNAME+2];
 151     uint8_t buf[BUFSIZ];
 152     int i;
 153     size_t j;
 154
 155     qoid[0] = 0;
 156     qoid[1] = 4;
 157     memcpy(qoid + 2, oid, len * sizeof(int));
 158
 159     j = sizeof(buf);
 160     i = sysctl(qoid, len + 2, buf, &j, 0, 0);
 161     if (i)
 162         return i;
 163
 164     if (kind)
 165         *kind = *(uint32_t *)buf;
 166
 167     if (fmt)
 168         strcpy(fmt, (char *)(buf + sizeof(uint32_t)));
 169     return (0);
 170 }
 171
 172 /*
 173  * try and convert sysctl return data for the target.
 174  * XXX doesn't handle CTLTYPE_OPAQUE and CTLTYPE_STRUCT.
 175  */
 176 static int sysctl_oldcvt(void *holdp, size_t holdlen, uint32_t kind)
 177 {
 178     switch (kind & CTLTYPE) {
 179     case CTLTYPE_INT:
 180     case CTLTYPE_UINT:
 181         *(uint32_t *)holdp = tswap32(*(uint32_t *)holdp);
 182         break;
 183 #ifdef TARGET_ABI32
 184     case CTLTYPE_LONG:
 185     case CTLTYPE_ULONG:
 186         *(uint32_t *)holdp = tswap32(*(long *)holdp);
 187         break;
 188 #else
 189     case CTLTYPE_LONG:
 190         *(uint64_t *)holdp = tswap64(*(long *)holdp);
 191         break;
 192     case CTLTYPE_ULONG:
 193         *(uint64_t *)holdp = tswap64(*(unsigned long *)holdp);
 194         break;
 195 #endif
 196 #ifdef CTLTYPE_U64
 197     case CTLTYPE_S64:
 198     case CTLTYPE_U64:
 199 #else
 200     case CTLTYPE_QUAD:
 201 #endif
 202         *(uint64_t *)holdp = tswap64(*(uint64_t *)holdp);
 203         break;
 204     case CTLTYPE_STRING:
 205         break;
 206     default:
 207         /* XXX unhandled */
 208         return -1;
 209     }
 210     return 0;
 211 }
 212
 213 /* XXX this needs to be emulated on non-FreeBSD hosts... */
 214 static abi_long do_freebsd_sysctl(abi_ulong namep, int32_t namelen, abi_ulong oldp,
 215                           abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen)
 216 {
 217     abi_long ret;
 218     void *hnamep, *holdp, *hnewp = NULL;
 219     size_t holdlen;
 220     abi_ulong oldlen = 0;
 221     int32_t *snamep = g_malloc(sizeof(int32_t) * namelen), *p, *q, i;
 222     uint32_t kind = 0;
 223
 224     if (oldlenp)
 225         get_user_ual(oldlen, oldlenp);
 226     if (!(hnamep = lock_user(VERIFY_READ, namep, namelen, 1)))
 227         return -TARGET_EFAULT;
 228     if (newp && !(hnewp = lock_user(VERIFY_READ, newp, newlen, 1)))
 229         return -TARGET_EFAULT;
 230     if (!(holdp = lock_user(VERIFY_WRITE, oldp, oldlen, 0)))
 231         return -TARGET_EFAULT;
 232     holdlen = oldlen;
 233     for (p = hnamep, q = snamep, i = 0; i < namelen; p++, i++)
 234        *q++ = tswap32(*p);
 235     oidfmt(snamep, namelen, NULL, &kind);
 236     /* XXX swap hnewp */
 237     ret = get_errno(sysctl(snamep, namelen, holdp, &holdlen, hnewp, newlen));
 238     if (!ret)
 239         sysctl_oldcvt(holdp, holdlen, kind);
 240     put_user_ual(holdlen, oldlenp);
 241     unlock_user(hnamep, namep, 0);
 242     unlock_user(holdp, oldp, holdlen);
 243     if (hnewp)
 244         unlock_user(hnewp, newp, 0);
 245     g_free(snamep);
 246     return ret;
 247 }
 248 #endif
 249
 250 /* FIXME
 251  * lock_iovec()/unlock_iovec() have a return code of 0 for success where
 252  * other lock functions have a return code of 0 for failure.
 253  */
 254 static abi_long lock_iovec(int type, struct iovec *vec, abi_ulong target_addr,
 255                            int count, int copy)
 256 {
 257     struct target_iovec *target_vec;
 258     abi_ulong base;
 259     int i;
 260
 261     target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 262     if (!target_vec)
 263         return -TARGET_EFAULT;
 264     for (i = 0;i < count; i++) {
 265         base = tswapl(target_vec[i].iov_base);
 266         vec[i].iov_len = tswapl(target_vec[i].iov_len);
 267         if (vec[i].iov_len != 0) {
 268             vec[i].iov_base = lock_user(type, base, vec[i].iov_len, copy);
 269             /* Don't check lock_user return value. We must call writev even
 270                if a element has invalid base address. */
 271         } else {
 272             /* zero length pointer is ignored */
 273             vec[i].iov_base = NULL;
 274         }
 275     }
 276     unlock_user (target_vec, target_addr, 0);
 277     return 0;
 278 }
 279
 280 static abi_long unlock_iovec(struct iovec *vec, abi_ulong target_addr,
 281                              int count, int copy)
 282 {
 283     struct target_iovec *target_vec;
 284     abi_ulong base;
 285     int i;
 286
 287     target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 288     if (!target_vec)
 289         return -TARGET_EFAULT;
 290     for (i = 0;i < count; i++) {
 291         if (target_vec[i].iov_base) {
 292             base = tswapl(target_vec[i].iov_base);
 293             unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0);
 294         }
 295     }
 296     unlock_user (target_vec, target_addr, 0);
 297
 298     return 0;
 299 }
 300
 301 /* do_syscall() should always have a single exit point at the end so
 302    that actions, such as logging of syscall results, can be performed.
 303    All errnos that do_syscall() returns must be -TARGET_<errcode>. */
 304 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 305                             abi_long arg2, abi_long arg3, abi_long arg4,
 306                             abi_long arg5, abi_long arg6, abi_long arg7,
 307                             abi_long arg8)
 308 {
 309     CPUState *cpu = env_cpu(cpu_env);
 310     abi_long ret;
 311     void *p;
 312
 313 #ifdef DEBUG
 314     gemu_log("freebsd syscall %d\n", num);
 315 #endif
 316     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 317
 318     if (do_strace)
 319         print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 320
 321     switch (num) {
 322     case TARGET_FREEBSD_NR_exit:
 323 #ifdef CONFIG_GPROF
 324         _mcleanup();
 325 #endif
 326         gdb_exit(arg1);
 327         qemu_plugin_user_exit();
 328         /* XXX: should free thread stack and CPU env */
 329         _exit(arg1);
 330         ret = 0; /* avoid warning */
 331         break;
 332     case TARGET_FREEBSD_NR_read:
 333         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 334             goto efault;
 335         ret = get_errno(read(arg1, p, arg3));
 336         unlock_user(p, arg2, ret);
 337         break;
 338     case TARGET_FREEBSD_NR_write:
 339         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 340             goto efault;
 341         ret = get_errno(write(arg1, p, arg3));
 342         unlock_user(p, arg2, 0);
 343         break;
 344     case TARGET_FREEBSD_NR_writev:
 345         {
 346             int count = arg3;
 347             struct iovec *vec;
 348
 349             vec = alloca(count * sizeof(struct iovec));
 350             if (lock_iovec(VERIFY_READ, vec, arg2, count, 1) < 0)
 351                 goto efault;
 352             ret = get_errno(writev(arg1, vec, count));
 353             unlock_iovec(vec, arg2, count, 0);
 354         }
 355         break;
 356     case TARGET_FREEBSD_NR_open:
 357         if (!(p = lock_user_string(arg1)))
 358             goto efault;
 359         ret = get_errno(open(path(p),
 360                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 361                              arg3));
 362         unlock_user(p, arg1, 0);
 363         break;
 364     case TARGET_FREEBSD_NR_mmap:
 365         ret = get_errno(target_mmap(arg1, arg2, arg3,
 366                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 367                                     arg5,
 368                                     arg6));
 369         break;
 370     case TARGET_FREEBSD_NR_mprotect:
 371         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 372         break;
 373     case TARGET_FREEBSD_NR_break:
 374         ret = do_obreak(arg1);
 375         break;
 376 #ifdef __FreeBSD__
 377     case TARGET_FREEBSD_NR___sysctl:
 378         ret = do_freebsd_sysctl(arg1, arg2, arg3, arg4, arg5, arg6);
 379         break;
 380 #endif
 381     case TARGET_FREEBSD_NR_sysarch:
 382         ret = do_freebsd_sysarch(cpu_env, arg1, arg2);
 383         break;
 384     case TARGET_FREEBSD_NR_syscall:
 385     case TARGET_FREEBSD_NR___syscall:
 386         ret = do_freebsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,arg7,arg8,0);
 387         break;
 388     default:
 389         ret = get_errno(syscall(num, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8));
 390         break;
 391     }
 392  fail:
 393 #ifdef DEBUG
 394     gemu_log(" = %ld\n", ret);
 395 #endif
 396     if (do_strace)
 397         print_freebsd_syscall_ret(num, ret);
 398
 399     record_syscall_return(cpu, num, ret);
 400     return ret;
 401  efault:
 402     ret = -TARGET_EFAULT;
 403     goto fail;
 404 }
 405
 406 abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
 407                            abi_long arg2, abi_long arg3, abi_long arg4,
 408                            abi_long arg5, abi_long arg6)
 409 {
 410     CPUState *cpu = env_cpu(cpu_env);
 411     abi_long ret;
 412     void *p;
 413
 414 #ifdef DEBUG
 415     gemu_log("netbsd syscall %d\n", num);
 416 #endif
 417
 418     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 419
 420     if (do_strace)
 421         print_netbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 422
 423     switch (num) {
 424     case TARGET_NETBSD_NR_exit:
 425 #ifdef CONFIG_GPROF
 426         _mcleanup();
 427 #endif
 428         gdb_exit(arg1);
 429         qemu_plugin_user_exit();
 430         /* XXX: should free thread stack and CPU env */
 431         _exit(arg1);
 432         ret = 0; /* avoid warning */
 433         break;
 434     case TARGET_NETBSD_NR_read:
 435         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 436             goto efault;
 437         ret = get_errno(read(arg1, p, arg3));
 438         unlock_user(p, arg2, ret);
 439         break;
 440     case TARGET_NETBSD_NR_write:
 441         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 442             goto efault;
 443         ret = get_errno(write(arg1, p, arg3));
 444         unlock_user(p, arg2, 0);
 445         break;
 446     case TARGET_NETBSD_NR_open:
 447         if (!(p = lock_user_string(arg1)))
 448             goto efault;
 449         ret = get_errno(open(path(p),
 450                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 451                              arg3));
 452         unlock_user(p, arg1, 0);
 453         break;
 454     case TARGET_NETBSD_NR_mmap:
 455         ret = get_errno(target_mmap(arg1, arg2, arg3,
 456                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 457                                     arg5,
 458                                     arg6));
 459         break;
 460     case TARGET_NETBSD_NR_mprotect:
 461         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 462         break;
 463     case TARGET_NETBSD_NR_syscall:
 464     case TARGET_NETBSD_NR___syscall:
 465         ret = do_netbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 466         break;
 467     default:
 468         ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 469         break;
 470     }
 471  fail:
 472 #ifdef DEBUG
 473     gemu_log(" = %ld\n", ret);
 474 #endif
 475     if (do_strace)
 476         print_netbsd_syscall_ret(num, ret);
 477
 478     record_syscall_return(cpu, num, ret);
 479     return ret;
 480  efault:
 481     ret = -TARGET_EFAULT;
 482     goto fail;
 483 }
 484
 485 abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
 486                             abi_long arg2, abi_long arg3, abi_long arg4,
 487                             abi_long arg5, abi_long arg6)
 488 {
 489     CPUState *cpu = env_cpu(cpu_env);
 490     abi_long ret;
 491     void *p;
 492
 493 #ifdef DEBUG
 494     gemu_log("openbsd syscall %d\n", num);
 495 #endif
 496
 497     record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 498
 499     if (do_strace)
 500         print_openbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 501
 502     switch (num) {
 503     case TARGET_OPENBSD_NR_exit:
 504 #ifdef CONFIG_GPROF
 505         _mcleanup();
 506 #endif
 507         gdb_exit(arg1);
 508         qemu_plugin_user_exit();
 509         /* XXX: should free thread stack and CPU env */
 510         _exit(arg1);
 511         ret = 0; /* avoid warning */
 512         break;
 513     case TARGET_OPENBSD_NR_read:
 514         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 515             goto efault;
 516         ret = get_errno(read(arg1, p, arg3));
 517         unlock_user(p, arg2, ret);
 518         break;
 519     case TARGET_OPENBSD_NR_write:
 520         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 521             goto efault;
 522         ret = get_errno(write(arg1, p, arg3));
 523         unlock_user(p, arg2, 0);
 524         break;
 525     case TARGET_OPENBSD_NR_open:
 526         if (!(p = lock_user_string(arg1)))
 527             goto efault;
 528         ret = get_errno(open(path(p),
 529                              target_to_host_bitmask(arg2, fcntl_flags_tbl),
 530                              arg3));
 531         unlock_user(p, arg1, 0);
 532         break;
 533     case TARGET_OPENBSD_NR_mmap:
 534         ret = get_errno(target_mmap(arg1, arg2, arg3,
 535                                     target_to_host_bitmask(arg4, mmap_flags_tbl),
 536                                     arg5,
 537                                     arg6));
 538         break;
 539     case TARGET_OPENBSD_NR_mprotect:
 540         ret = get_errno(target_mprotect(arg1, arg2, arg3));
 541         break;
 542     case TARGET_OPENBSD_NR_syscall:
 543     case TARGET_OPENBSD_NR___syscall:
 544         ret = do_openbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 545         break;
 546     default:
 547         ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 548         break;
 549     }
 550  fail:
 551 #ifdef DEBUG
 552     gemu_log(" = %ld\n", ret);
 553 #endif
 554     if (do_strace)
 555         print_openbsd_syscall_ret(num, ret);
 556
 557     record_syscall_return(cpu, num, ret);
 558     return ret;
 559  efault:
 560     ret = -TARGET_EFAULT;
 561     goto fail;
 562 }
 563
 564 void syscall_init(void)
 565 {
 566 }