i386-linux.c revision 86501
1/* 2 * Copryight 1997 Sean Eric Fagan 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. All advertising materials mentioning features or use of this software 13 * must display the following acknowledgement: 14 * This product includes software developed by Sean Eric Fagan 15 * 4. Neither the name of the author may be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32#ifndef lint 33static const char rcsid[] = 34 "$FreeBSD: head/usr.bin/truss/i386-linux.c 86501 2001-11-17 17:18:36Z des $"; 35#endif /* not lint */ 36 37/* 38 * Linux/i386-specific system call handling. Given how much of this code 39 * is taken from the freebsd equivalent, I can probably put even more of 40 * it in support routines that can be used by any personality support. 41 */ 42 43#include <sys/types.h> 44#include <sys/ioctl.h> 45#include <sys/pioctl.h> 46 47#include <machine/reg.h> 48#include <machine/psl.h> 49 50#include <errno.h> 51#include <fcntl.h> 52#include <signal.h> 53#include <stdio.h> 54#include <stdlib.h> 55#include <string.h> 56#include <unistd.h> 57 58#include "syscall.h" 59 60static int fd = -1; 61static int cpid = -1; 62extern int Procfd; 63 64extern FILE *outfile; 65#include "linux_syscalls.h" 66 67static int nsyscalls = 68 sizeof(linux_syscallnames) / sizeof(linux_syscallnames[0]); 69 70/* See the comment in i386-fbsd.c about this structure. */ 71static struct linux_syscall { 72 struct syscall *sc; 73 char *name; 74 int number; 75 unsigned long args[5]; 76 int nargs; /* number of arguments -- *not* number of words! */ 77 char **s_args; /* the printable arguments */ 78} lsc; 79 80static inline void 81clear_lsc() { 82 if (lsc.s_args) { 83 int i; 84 for (i = 0; i < lsc.nargs; i++) 85 if (lsc.s_args[i]) 86 free(lsc.s_args[i]); 87 free(lsc.s_args); 88 } 89 memset(&lsc, 0, sizeof(lsc)); 90} 91 92void 93i386_linux_syscall_entry(int pid, int nargs) { 94 char buf[32]; 95 struct reg regs = { 0 }; 96 int syscall; 97 int i; 98 struct syscall *sc; 99 100 if (fd == -1 || pid != cpid) { 101 sprintf(buf, "/proc/%d/regs", pid); 102 fd = open(buf, O_RDWR); 103 if (fd == -1) { 104 fprintf(outfile, "-- CANNOT READ REGISTERS --\n"); 105 return; 106 } 107 cpid = pid; 108 } 109 110 clear_lsc(); 111 lseek(fd, 0L, 0); 112 i = read(fd, ®s, sizeof(regs)); 113 syscall = regs.r_eax; 114 115 lsc.number = syscall; 116 lsc.name = 117 (syscall < 0 || syscall > nsyscalls) ? NULL : linux_syscallnames[syscall]; 118 if (!lsc.name) { 119 fprintf (outfile, "-- UNKNOWN SYSCALL %d\n", syscall); 120 } 121 122 if (nargs == 0) 123 return; 124 125 /* 126 * Linux passes syscall arguments in registers, not 127 * on the stack. Fortunately, we've got access to the 128 * register set. Note that we don't bother checking the 129 * number of arguments. And what does linux do for syscalls 130 * that have more than five arguments? 131 */ 132 133 lsc.args[0] = regs.r_ebx; 134 lsc.args[1] = regs.r_ecx; 135 lsc.args[2] = regs.r_edx; 136 lsc.args[3] = regs.r_esi; 137 lsc.args[4] = regs.r_edi; 138 139 sc = get_syscall(lsc.name); 140 if (sc) { 141 lsc.nargs = sc->nargs; 142 } else { 143#ifdef DEBUG 144 fprintf(outfile, "unknown syscall %s -- setting args to %d\n", 145 lsc.name, nargs); 146#endif 147 lsc.nargs = nargs; 148 } 149 150 lsc.s_args = malloc((1+lsc.nargs) * sizeof(char*)); 151 memset(lsc.s_args, 0, lsc.nargs * sizeof(char*)); 152 lsc.sc = sc; 153 154 if (lsc.name) { 155 156#ifdef DEBUG 157 fprintf(stderr, "syscall %s(", lsc.name); 158#endif 159 for (i = 0; i < lsc.nargs ; i++) { 160#ifdef DEBUG 161 fprintf(stderr, "0x%x%s", 162 sc ? 163 lsc.args[sc->args[i].offset] 164 : lsc.args[i], 165 i < (lsc.nargs - 1) ? "," : ""); 166#endif 167 if (sc && !(sc->args[i].type & OUT)) { 168 lsc.s_args[i] = print_arg(Procfd, &sc->args[i], lsc.args); 169 } 170 } 171#ifdef DEBUG 172 fprintf(stderr, ")\n"); 173#endif 174 } 175 176 if (!strcmp(lsc.name, "linux_execve") || !strcmp(lsc.name, "exit")) { 177 print_syscall(outfile, lsc.name, lsc.nargs, lsc.s_args); 178 } 179 180 return; 181} 182 183/* 184 * Linux syscalls return negative errno's, we do positive and map them 185 */ 186int bsd_to_linux_errno[] = { 187 -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, 188 -10, -35, -12, -13, -14, -15, -16, -17, -18, -19, 189 -20, -21, -22, -23, -24, -25, -26, -27, -28, -29, 190 -30, -31, -32, -33, -34, -11,-115,-114, -88, -89, 191 -90, -91, -92, -93, -94, -95, -96, -97, -98, -99, 192 -100,-101,-102,-103,-104,-105,-106,-107,-108,-109, 193 -110,-111, -40, -36,-112,-113, -39, -11, -87,-122, 194 -116, -66, -6, -6, -6, -6, -6, -37, -38, -9, 195 -6, 196}; 197 198void 199i386_linux_syscall_exit(int pid, int syscall) { 200 char buf[32]; 201 struct reg regs; 202 int retval; 203 int i; 204 int errorp; 205 struct syscall *sc; 206 207 if (fd == -1 || pid != cpid) { 208 sprintf(buf, "/proc/%d/regs", pid); 209 fd = open(buf, O_RDONLY); 210 if (fd == -1) { 211 fprintf(outfile, "-- CANNOT READ REGISTERS --\n"); 212 return; 213 } 214 cpid = pid; 215 } 216 217 lseek(fd, 0L, 0); 218 if (read(fd, ®s, sizeof(regs)) != sizeof(regs)) 219 return; 220 221 retval = regs.r_eax; 222 errorp = !!(regs.r_eflags & PSL_C); 223 224 sc = lsc.sc; 225 if (!sc) { 226 for (i = 0; i < lsc.nargs; i++) { 227 lsc.s_args[i] = malloc(12); 228 sprintf(lsc.s_args[i], "0x%lx", lsc.args[i]); 229 } 230 } else { 231 for (i = 0; i < sc->nargs; i++) { 232 char *temp; 233 if (sc->args[i].type & OUT) { 234 if (errorp) { 235 temp = malloc(12); 236 sprintf(temp, "0x%lx", lsc.args[sc->args[i].offset]); 237 } else { 238 temp = print_arg(Procfd, &sc->args[i], lsc.args); 239 } 240 lsc.s_args[i] = temp; 241 } 242 } 243 } 244 if (errorp) { 245 for (i = 0; i < sizeof(bsd_to_linux_errno) / sizeof(int); i++) 246 if (retval == bsd_to_linux_errno[i]) 247 break; 248 } 249 print_syscall_ret(outfile, lsc.name, lsc.nargs, lsc.s_args, errorp, 250 errorp ? i : retval); 251 clear_lsc(); 252 return; 253} 254