bsd-user/strace.c

   1 /*
   2  *  System call tracing and debugging
   3  *
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include "qemu/osdep.h"
  20 #include <sys/select.h>
  21 #include <sys/syscall.h>
  22 #include <sys/ioccom.h>
  23
  24 #include "qemu.h"
  25
  26 #include "os-strace.h"  /* OS dependent strace print functions */
  27
  28 int do_strace;
  29
  30 /*
  31  * Utility functions
  32  */
  33 static const char *
  34 get_comma(int last)
  35 {
  36     return (last) ? "" : ",";
  37 }
  38
  39 /*
  40  * Prints out raw parameter using given format.  Caller needs
  41  * to do byte swapping if needed.
  42  */
  43 static void
  44 print_raw_param(const char *fmt, abi_long param, int last)
  45 {
  46     char format[64];
  47
  48     (void)snprintf(format, sizeof(format), "%s%s", fmt, get_comma(last));
  49     gemu_log(format, param);
  50 }
  51
  52 static void print_sysctl(const struct syscallname *name, abi_long arg1,
  53         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
  54         abi_long arg6)
  55 {
  56     uint32_t i;
  57     int32_t *namep;
  58
  59     gemu_log("%s({ ", name->name);
  60     namep = lock_user(VERIFY_READ, arg1, sizeof(int32_t) * arg2, 1);
  61     if (namep) {
  62         int32_t *p = namep;
  63
  64         for (i = 0; i < (uint32_t)arg2; i++) {
  65             gemu_log("%d ", tswap32(*p++));
  66         }
  67         unlock_user(namep, arg1, 0);
  68     }
  69     gemu_log("}, %u, 0x" TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ", 0x"
  70         TARGET_ABI_FMT_lx ", 0x" TARGET_ABI_FMT_lx ")",
  71         (uint32_t)arg2, arg3, arg4, arg5, arg6);
  72 }
  73
  74 static void print_execve(const struct syscallname *name, abi_long arg1,
  75         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
  76         abi_long arg6)
  77 {
  78     abi_ulong arg_ptr_addr;
  79     char *s;
  80
  81     s = lock_user_string(arg1);
  82     if (s == NULL) {
  83         return;
  84     }
  85     gemu_log("%s(\"%s\",{", name->name, s);
  86     unlock_user(s, arg1, 0);
  87
  88     for (arg_ptr_addr = arg2; ; arg_ptr_addr += sizeof(abi_ulong)) {
  89         abi_ulong *arg_ptr, arg_addr;
  90
  91         arg_ptr = lock_user(VERIFY_READ, arg_ptr_addr, sizeof(abi_ulong), 1);
  92         if (!arg_ptr) {
  93             return;
  94         }
  95         arg_addr = tswapl(*arg_ptr);
  96         unlock_user(arg_ptr, arg_ptr_addr, 0);
  97         if (!arg_addr) {
  98             break;
  99         }
 100         if ((s = lock_user_string(arg_addr))) {
 101             gemu_log("\"%s\",", s);
 102             unlock_user(s, arg_addr, 0);
 103         }
 104     }
 105     gemu_log("NULL})");
 106 }
 107
 108 static void print_ioctl(const struct syscallname *name,
 109         abi_long arg1, abi_long arg2, abi_long arg3, abi_long arg4,
 110         abi_long arg5, abi_long arg6)
 111 {
 112     /* Decode the ioctl request */
 113     gemu_log("%s(%d, 0x%0lx { IO%s%s GRP:0x%x('%c') CMD:%d LEN:%d }, 0x"
 114             TARGET_ABI_FMT_lx ", ...)",
 115             name->name,
 116             (int)arg1,
 117             (unsigned long)arg2,
 118             arg2 & IOC_OUT ? "R" : "",
 119             arg2 & IOC_IN ? "W" : "",
 120             (unsigned)IOCGROUP(arg2),
 121             isprint(IOCGROUP(arg2)) ? (char)IOCGROUP(arg2) : '?',
 122             (int)arg2 & 0xFF,
 123             (int)IOCPARM_LEN(arg2),
 124             arg3);
 125 }
 126
 127 static void print_sysarch(const struct syscallname *name, abi_long arg1,
 128         abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5,
 129         abi_long arg6)
 130 {
 131     /* This is os dependent. */
 132     do_os_print_sysarch(name, arg1, arg2, arg3, arg4, arg5, arg6);
 133 }
 134
 135 /*
 136  * Variants for the return value output function
 137  */
 138
 139 static void print_syscall_ret_addr(const struct syscallname *name, abi_long ret)
 140 {
 141     if (ret == -1) {
 142         gemu_log(" = -1 errno=%d (%s)\n", errno, strerror(errno));
 143     } else {
 144         gemu_log(" = 0x" TARGET_ABI_FMT_lx "\n", ret);
 145     }
 146 }
 147
 148 /*
 149  * An array of all of the syscalls we know about
 150  */
 151
 152 static const struct syscallname freebsd_scnames[] = {
 153 #include "freebsd/strace.list"
 154 };
 155 static const struct syscallname netbsd_scnames[] = {
 156 #include "netbsd/strace.list"
 157 };
 158 static const struct syscallname openbsd_scnames[] = {
 159 #include "openbsd/strace.list"
 160 };
 161
 162 static void print_syscall(int num, const struct syscallname *scnames,
 163         unsigned int nscnames, abi_long arg1, abi_long arg2, abi_long arg3,
 164         abi_long arg4, abi_long arg5, abi_long arg6)
 165 {
 166     unsigned int i;
 167     const char *format="%s(" TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
 168         TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld "," TARGET_ABI_FMT_ld ","
 169         TARGET_ABI_FMT_ld ")";
 170
 171     gemu_log("%d ", getpid() );
 172
 173     for (i = 0; i < nscnames; i++) {
 174         if (scnames[i].nr == num) {
 175             if (scnames[i].call != NULL) {
 176                 scnames[i].call(&scnames[i], arg1, arg2, arg3, arg4, arg5,
 177                         arg6);
 178             } else {
 179                 /* XXX: this format system is broken because it uses
 180                    host types and host pointers for strings */
 181                 if (scnames[i].format != NULL) {
 182                     format = scnames[i].format;
 183                 }
 184                 gemu_log(format, scnames[i].name, arg1, arg2, arg3, arg4, arg5,
 185                         arg6);
 186             }
 187             return;
 188         }
 189     }
 190     gemu_log("Unknown syscall %d\n", num);
 191 }
 192
 193 static void print_syscall_ret(int num, abi_long ret,
 194         const struct syscallname *scnames, unsigned int nscnames)
 195 {
 196     unsigned int i;
 197
 198     for (i = 0; i < nscnames; i++) {
 199         if (scnames[i].nr == num) {
 200             if (scnames[i].result != NULL) {
 201                 scnames[i].result(&scnames[i], ret);
 202             } else {
 203                 if (ret < 0) {
 204                     gemu_log(" = -1 errno=" TARGET_ABI_FMT_ld " (%s)\n", -ret,
 205                              strerror(-ret));
 206                 } else {
 207                     gemu_log(" = " TARGET_ABI_FMT_ld "\n", ret);
 208                 }
 209             }
 210             break;
 211         }
 212     }
 213 }
 214
 215 /*
 216  * The public interface to this module.
 217  */
 218 void print_freebsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
 219         abi_long arg4, abi_long arg5, abi_long arg6)
 220 {
 221
 222     print_syscall(num, freebsd_scnames, ARRAY_SIZE(freebsd_scnames), arg1, arg2,
 223             arg3, arg4, arg5, arg6);
 224 }
 225
 226 void print_freebsd_syscall_ret(int num, abi_long ret)
 227 {
 228
 229     print_syscall_ret(num, ret, freebsd_scnames, ARRAY_SIZE(freebsd_scnames));
 230 }
 231
 232 void print_netbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
 233         abi_long arg4, abi_long arg5, abi_long arg6)
 234 {
 235
 236     print_syscall(num, netbsd_scnames, ARRAY_SIZE(netbsd_scnames),
 237                   arg1, arg2, arg3, arg4, arg5, arg6);
 238 }
 239
 240 void print_netbsd_syscall_ret(int num, abi_long ret)
 241 {
 242
 243     print_syscall_ret(num, ret, netbsd_scnames, ARRAY_SIZE(netbsd_scnames));
 244 }
 245
 246 void print_openbsd_syscall(int num, abi_long arg1, abi_long arg2, abi_long arg3,
 247         abi_long arg4, abi_long arg5, abi_long arg6)
 248 {
 249
 250     print_syscall(num, openbsd_scnames, ARRAY_SIZE(openbsd_scnames), arg1, arg2,
 251             arg3, arg4, arg5, arg6);
 252 }
 253
 254 void print_openbsd_syscall_ret(int num, abi_long ret)
 255 {
 256
 257     print_syscall_ret(num, ret, openbsd_scnames, ARRAY_SIZE(openbsd_scnames));
 258 }
 259
 260 static void
 261 print_signal(abi_ulong arg, int last)
 262 {
 263     const char *signal_name = NULL;
 264     switch (arg) {
 265     case TARGET_SIGHUP:
 266         signal_name = "SIGHUP";
 267         break;
 268     case TARGET_SIGINT:
 269         signal_name = "SIGINT";
 270         break;
 271     case TARGET_SIGQUIT:
 272         signal_name = "SIGQUIT";
 273         break;
 274     case TARGET_SIGILL:
 275         signal_name = "SIGILL";
 276         break;
 277     case TARGET_SIGABRT:
 278         signal_name = "SIGABRT";
 279         break;
 280     case TARGET_SIGFPE:
 281         signal_name = "SIGFPE";
 282         break;
 283     case TARGET_SIGKILL:
 284         signal_name = "SIGKILL";
 285         break;
 286     case TARGET_SIGSEGV:
 287         signal_name = "SIGSEGV";
 288         break;
 289     case TARGET_SIGPIPE:
 290         signal_name = "SIGPIPE";
 291         break;
 292     case TARGET_SIGALRM:
 293         signal_name = "SIGALRM";
 294         break;
 295     case TARGET_SIGTERM:
 296         signal_name = "SIGTERM";
 297         break;
 298     case TARGET_SIGUSR1:
 299         signal_name = "SIGUSR1";
 300         break;
 301     case TARGET_SIGUSR2:
 302         signal_name = "SIGUSR2";
 303         break;
 304     case TARGET_SIGCHLD:
 305         signal_name = "SIGCHLD";
 306         break;
 307     case TARGET_SIGCONT:
 308         signal_name = "SIGCONT";
 309         break;
 310     case TARGET_SIGSTOP:
 311         signal_name = "SIGSTOP";
 312         break;
 313     case TARGET_SIGTTIN:
 314         signal_name = "SIGTTIN";
 315         break;
 316     case TARGET_SIGTTOU:
 317         signal_name = "SIGTTOU";
 318         break;
 319     }
 320     if (signal_name == NULL) {
 321         print_raw_param("%ld", arg, last);
 322         return;
 323     }
 324     gemu_log("%s%s", signal_name, get_comma(last));
 325 }
 326
 327 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo)
 328 {
 329     /*
 330      * Print the strace output for a signal being taken:
 331      * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
 332      */
 333     gemu_log("%d ", getpid());
 334     gemu_log("--- ");
 335     print_signal(target_signum, 1);
 336     gemu_log(" ---\n");
 337 }