qemu/bsd-user/syscall.c
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   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
  33static abi_ulong target_brk;
  34static abi_ulong target_original_brk;
  35
  36abi_long get_errno(abi_long ret)
  37{
  38    if (ret == -1) {
  39        /* XXX need to translate host -> target errnos here */
  40        return -(errno);
  41    }
  42    return ret;
  43}
  44
  45#define target_to_host_bitmask(x, tbl) (x)
  46
  47bool is_error(abi_long ret)
  48{
  49    return (abi_ulong)ret >= (abi_ulong)(-4096);
  50}
  51
  52void 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. */
  58static 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#ifdef __FreeBSD__
  92/*
  93 * XXX this uses the undocumented oidfmt interface to find the kind of
  94 * a requested sysctl, see /sys/kern/kern_sysctl.c:sysctl_sysctl_oidfmt()
  95 * (this is mostly copied from src/sbin/sysctl/sysctl.c)
  96 */
  97static int
  98oidfmt(int *oid, int len, char *fmt, uint32_t *kind)
  99{
 100    int qoid[CTL_MAXNAME+2];
 101    uint8_t buf[BUFSIZ];
 102    int i;
 103    size_t j;
 104
 105    qoid[0] = 0;
 106    qoid[1] = 4;
 107    memcpy(qoid + 2, oid, len * sizeof(int));
 108
 109    j = sizeof(buf);
 110    i = sysctl(qoid, len + 2, buf, &j, 0, 0);
 111    if (i)
 112        return i;
 113
 114    if (kind)
 115        *kind = *(uint32_t *)buf;
 116
 117    if (fmt)
 118        strcpy(fmt, (char *)(buf + sizeof(uint32_t)));
 119    return (0);
 120}
 121
 122/*
 123 * try and convert sysctl return data for the target.
 124 * XXX doesn't handle CTLTYPE_OPAQUE and CTLTYPE_STRUCT.
 125 */
 126static int sysctl_oldcvt(void *holdp, size_t holdlen, uint32_t kind)
 127{
 128    switch (kind & CTLTYPE) {
 129    case CTLTYPE_INT:
 130    case CTLTYPE_UINT:
 131        *(uint32_t *)holdp = tswap32(*(uint32_t *)holdp);
 132        break;
 133#ifdef TARGET_ABI32
 134    case CTLTYPE_LONG:
 135    case CTLTYPE_ULONG:
 136        *(uint32_t *)holdp = tswap32(*(long *)holdp);
 137        break;
 138#else
 139    case CTLTYPE_LONG:
 140        *(uint64_t *)holdp = tswap64(*(long *)holdp);
 141        break;
 142    case CTLTYPE_ULONG:
 143        *(uint64_t *)holdp = tswap64(*(unsigned long *)holdp);
 144        break;
 145#endif
 146#ifdef CTLTYPE_U64
 147    case CTLTYPE_S64:
 148    case CTLTYPE_U64:
 149#else
 150    case CTLTYPE_QUAD:
 151#endif
 152        *(uint64_t *)holdp = tswap64(*(uint64_t *)holdp);
 153        break;
 154    case CTLTYPE_STRING:
 155        break;
 156    default:
 157        /* XXX unhandled */
 158        return -1;
 159    }
 160    return 0;
 161}
 162
 163/* XXX this needs to be emulated on non-FreeBSD hosts... */
 164static abi_long do_freebsd_sysctl(abi_ulong namep, int32_t namelen, abi_ulong oldp,
 165                          abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen)
 166{
 167    abi_long ret;
 168    void *hnamep, *holdp, *hnewp = NULL;
 169    size_t holdlen;
 170    abi_ulong oldlen = 0;
 171    int32_t *snamep = g_malloc(sizeof(int32_t) * namelen), *p, *q, i;
 172    uint32_t kind = 0;
 173
 174    if (oldlenp)
 175        get_user_ual(oldlen, oldlenp);
 176    if (!(hnamep = lock_user(VERIFY_READ, namep, namelen, 1)))
 177        return -TARGET_EFAULT;
 178    if (newp && !(hnewp = lock_user(VERIFY_READ, newp, newlen, 1)))
 179        return -TARGET_EFAULT;
 180    if (!(holdp = lock_user(VERIFY_WRITE, oldp, oldlen, 0)))
 181        return -TARGET_EFAULT;
 182    holdlen = oldlen;
 183    for (p = hnamep, q = snamep, i = 0; i < namelen; p++, i++)
 184       *q++ = tswap32(*p);
 185    oidfmt(snamep, namelen, NULL, &kind);
 186    /* XXX swap hnewp */
 187    ret = get_errno(sysctl(snamep, namelen, holdp, &holdlen, hnewp, newlen));
 188    if (!ret)
 189        sysctl_oldcvt(holdp, holdlen, kind);
 190    put_user_ual(holdlen, oldlenp);
 191    unlock_user(hnamep, namep, 0);
 192    unlock_user(holdp, oldp, holdlen);
 193    if (hnewp)
 194        unlock_user(hnewp, newp, 0);
 195    g_free(snamep);
 196    return ret;
 197}
 198#endif
 199
 200/* FIXME
 201 * lock_iovec()/unlock_iovec() have a return code of 0 for success where
 202 * other lock functions have a return code of 0 for failure.
 203 */
 204static abi_long lock_iovec(int type, struct iovec *vec, abi_ulong target_addr,
 205                           int count, int copy)
 206{
 207    struct target_iovec *target_vec;
 208    abi_ulong base;
 209    int i;
 210
 211    target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 212    if (!target_vec)
 213        return -TARGET_EFAULT;
 214    for (i = 0;i < count; i++) {
 215        base = tswapl(target_vec[i].iov_base);
 216        vec[i].iov_len = tswapl(target_vec[i].iov_len);
 217        if (vec[i].iov_len != 0) {
 218            vec[i].iov_base = lock_user(type, base, vec[i].iov_len, copy);
 219            /* Don't check lock_user return value. We must call writev even
 220               if a element has invalid base address. */
 221        } else {
 222            /* zero length pointer is ignored */
 223            vec[i].iov_base = NULL;
 224        }
 225    }
 226    unlock_user (target_vec, target_addr, 0);
 227    return 0;
 228}
 229
 230static abi_long unlock_iovec(struct iovec *vec, abi_ulong target_addr,
 231                             int count, int copy)
 232{
 233    struct target_iovec *target_vec;
 234    abi_ulong base;
 235    int i;
 236
 237    target_vec = lock_user(VERIFY_READ, target_addr, count * sizeof(struct target_iovec), 1);
 238    if (!target_vec)
 239        return -TARGET_EFAULT;
 240    for (i = 0;i < count; i++) {
 241        if (target_vec[i].iov_base) {
 242            base = tswapl(target_vec[i].iov_base);
 243            unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0);
 244        }
 245    }
 246    unlock_user (target_vec, target_addr, 0);
 247
 248    return 0;
 249}
 250
 251/* do_syscall() should always have a single exit point at the end so
 252   that actions, such as logging of syscall results, can be performed.
 253   All errnos that do_syscall() returns must be -TARGET_<errcode>. */
 254abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 255                            abi_long arg2, abi_long arg3, abi_long arg4,
 256                            abi_long arg5, abi_long arg6, abi_long arg7,
 257                            abi_long arg8)
 258{
 259    CPUState *cpu = env_cpu(cpu_env);
 260    abi_long ret;
 261    void *p;
 262
 263#ifdef DEBUG
 264    gemu_log("freebsd syscall %d\n", num);
 265#endif
 266    record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 267
 268    if (do_strace)
 269        print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 270
 271    switch (num) {
 272    case TARGET_FREEBSD_NR_exit:
 273#ifdef CONFIG_GPROF
 274        _mcleanup();
 275#endif
 276        gdb_exit(arg1);
 277        qemu_plugin_user_exit();
 278        /* XXX: should free thread stack and CPU env */
 279        _exit(arg1);
 280        ret = 0; /* avoid warning */
 281        break;
 282    case TARGET_FREEBSD_NR_read:
 283        if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 284            goto efault;
 285        ret = get_errno(read(arg1, p, arg3));
 286        unlock_user(p, arg2, ret);
 287        break;
 288    case TARGET_FREEBSD_NR_write:
 289        if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 290            goto efault;
 291        ret = get_errno(write(arg1, p, arg3));
 292        unlock_user(p, arg2, 0);
 293        break;
 294    case TARGET_FREEBSD_NR_writev:
 295        {
 296            int count = arg3;
 297            struct iovec *vec;
 298
 299            vec = alloca(count * sizeof(struct iovec));
 300            if (lock_iovec(VERIFY_READ, vec, arg2, count, 1) < 0)
 301                goto efault;
 302            ret = get_errno(writev(arg1, vec, count));
 303            unlock_iovec(vec, arg2, count, 0);
 304        }
 305        break;
 306    case TARGET_FREEBSD_NR_open:
 307        if (!(p = lock_user_string(arg1)))
 308            goto efault;
 309        ret = get_errno(open(path(p),
 310                             target_to_host_bitmask(arg2, fcntl_flags_tbl),
 311                             arg3));
 312        unlock_user(p, arg1, 0);
 313        break;
 314    case TARGET_FREEBSD_NR_mmap:
 315        ret = get_errno(target_mmap(arg1, arg2, arg3,
 316                                    target_to_host_bitmask(arg4, mmap_flags_tbl),
 317                                    arg5,
 318                                    arg6));
 319        break;
 320    case TARGET_FREEBSD_NR_mprotect:
 321        ret = get_errno(target_mprotect(arg1, arg2, arg3));
 322        break;
 323    case TARGET_FREEBSD_NR_break:
 324        ret = do_obreak(arg1);
 325        break;
 326#ifdef __FreeBSD__
 327    case TARGET_FREEBSD_NR___sysctl:
 328        ret = do_freebsd_sysctl(arg1, arg2, arg3, arg4, arg5, arg6);
 329        break;
 330#endif
 331    case TARGET_FREEBSD_NR_sysarch:
 332        ret = do_freebsd_sysarch(cpu_env, arg1, arg2);
 333        break;
 334    case TARGET_FREEBSD_NR_syscall:
 335    case TARGET_FREEBSD_NR___syscall:
 336        ret = do_freebsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,arg7,arg8,0);
 337        break;
 338    default:
 339        ret = get_errno(syscall(num, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8));
 340        break;
 341    }
 342 fail:
 343#ifdef DEBUG
 344    gemu_log(" = %ld\n", ret);
 345#endif
 346    if (do_strace)
 347        print_freebsd_syscall_ret(num, ret);
 348
 349    record_syscall_return(cpu, num, ret);
 350    return ret;
 351 efault:
 352    ret = -TARGET_EFAULT;
 353    goto fail;
 354}
 355
 356abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
 357                           abi_long arg2, abi_long arg3, abi_long arg4,
 358                           abi_long arg5, abi_long arg6)
 359{
 360    CPUState *cpu = env_cpu(cpu_env);
 361    abi_long ret;
 362    void *p;
 363
 364#ifdef DEBUG
 365    gemu_log("netbsd syscall %d\n", num);
 366#endif
 367
 368    record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 369
 370    if (do_strace)
 371        print_netbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 372
 373    switch (num) {
 374    case TARGET_NETBSD_NR_exit:
 375#ifdef CONFIG_GPROF
 376        _mcleanup();
 377#endif
 378        gdb_exit(arg1);
 379        qemu_plugin_user_exit();
 380        /* XXX: should free thread stack and CPU env */
 381        _exit(arg1);
 382        ret = 0; /* avoid warning */
 383        break;
 384    case TARGET_NETBSD_NR_read:
 385        if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 386            goto efault;
 387        ret = get_errno(read(arg1, p, arg3));
 388        unlock_user(p, arg2, ret);
 389        break;
 390    case TARGET_NETBSD_NR_write:
 391        if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 392            goto efault;
 393        ret = get_errno(write(arg1, p, arg3));
 394        unlock_user(p, arg2, 0);
 395        break;
 396    case TARGET_NETBSD_NR_open:
 397        if (!(p = lock_user_string(arg1)))
 398            goto efault;
 399        ret = get_errno(open(path(p),
 400                             target_to_host_bitmask(arg2, fcntl_flags_tbl),
 401                             arg3));
 402        unlock_user(p, arg1, 0);
 403        break;
 404    case TARGET_NETBSD_NR_mmap:
 405        ret = get_errno(target_mmap(arg1, arg2, arg3,
 406                                    target_to_host_bitmask(arg4, mmap_flags_tbl),
 407                                    arg5,
 408                                    arg6));
 409        break;
 410    case TARGET_NETBSD_NR_mprotect:
 411        ret = get_errno(target_mprotect(arg1, arg2, arg3));
 412        break;
 413    case TARGET_NETBSD_NR_syscall:
 414    case TARGET_NETBSD_NR___syscall:
 415        ret = do_netbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 416        break;
 417    default:
 418        ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 419        break;
 420    }
 421 fail:
 422#ifdef DEBUG
 423    gemu_log(" = %ld\n", ret);
 424#endif
 425    if (do_strace)
 426        print_netbsd_syscall_ret(num, ret);
 427
 428    record_syscall_return(cpu, num, ret);
 429    return ret;
 430 efault:
 431    ret = -TARGET_EFAULT;
 432    goto fail;
 433}
 434
 435abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
 436                            abi_long arg2, abi_long arg3, abi_long arg4,
 437                            abi_long arg5, abi_long arg6)
 438{
 439    CPUState *cpu = env_cpu(cpu_env);
 440    abi_long ret;
 441    void *p;
 442
 443#ifdef DEBUG
 444    gemu_log("openbsd syscall %d\n", num);
 445#endif
 446
 447    record_syscall_start(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, 0, 0);
 448
 449    if (do_strace)
 450        print_openbsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 451
 452    switch (num) {
 453    case TARGET_OPENBSD_NR_exit:
 454#ifdef CONFIG_GPROF
 455        _mcleanup();
 456#endif
 457        gdb_exit(arg1);
 458        qemu_plugin_user_exit();
 459        /* XXX: should free thread stack and CPU env */
 460        _exit(arg1);
 461        ret = 0; /* avoid warning */
 462        break;
 463    case TARGET_OPENBSD_NR_read:
 464        if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
 465            goto efault;
 466        ret = get_errno(read(arg1, p, arg3));
 467        unlock_user(p, arg2, ret);
 468        break;
 469    case TARGET_OPENBSD_NR_write:
 470        if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
 471            goto efault;
 472        ret = get_errno(write(arg1, p, arg3));
 473        unlock_user(p, arg2, 0);
 474        break;
 475    case TARGET_OPENBSD_NR_open:
 476        if (!(p = lock_user_string(arg1)))
 477            goto efault;
 478        ret = get_errno(open(path(p),
 479                             target_to_host_bitmask(arg2, fcntl_flags_tbl),
 480                             arg3));
 481        unlock_user(p, arg1, 0);
 482        break;
 483    case TARGET_OPENBSD_NR_mmap:
 484        ret = get_errno(target_mmap(arg1, arg2, arg3,
 485                                    target_to_host_bitmask(arg4, mmap_flags_tbl),
 486                                    arg5,
 487                                    arg6));
 488        break;
 489    case TARGET_OPENBSD_NR_mprotect:
 490        ret = get_errno(target_mprotect(arg1, arg2, arg3));
 491        break;
 492    case TARGET_OPENBSD_NR_syscall:
 493    case TARGET_OPENBSD_NR___syscall:
 494        ret = do_openbsd_syscall(cpu_env,arg1 & 0xffff,arg2,arg3,arg4,arg5,arg6,0);
 495        break;
 496    default:
 497        ret = syscall(num, arg1, arg2, arg3, arg4, arg5, arg6);
 498        break;
 499    }
 500 fail:
 501#ifdef DEBUG
 502    gemu_log(" = %ld\n", ret);
 503#endif
 504    if (do_strace)
 505        print_openbsd_syscall_ret(num, ret);
 506
 507    record_syscall_return(cpu, num, ret);
 508    return ret;
 509 efault:
 510    ret = -TARGET_EFAULT;
 511    goto fail;
 512}
 513
 514void syscall_init(void)
 515{
 516}
 517