mips-fbsd.c revision 241162
1/* 2 * Copyright 1998 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: stable/9/usr.bin/truss/mips-fbsd.c 241162 2012-10-03 14:28:55Z zont $"; 35#endif /* not lint */ 36 37/* 38 * FreeBSD/sparc64-specific system call handling. This is probably the most 39 * complex part of the entire truss program, although I've got lots of 40 * it handled relatively cleanly now. The system call names are generated 41 * automatically, thanks to /usr/src/sys/kern/syscalls.master. The 42 * names used for the various structures are confusing, I sadly admit. 43 * 44 * This file is almost nothing more than a slightly-edited i386-fbsd.c. 45 */ 46 47#include <sys/types.h> 48#include <sys/ptrace.h> 49#include <sys/syscall.h> 50 51#include <machine/frame.h> 52#include <machine/reg.h> 53 54#include <err.h> 55#include <errno.h> 56#include <fcntl.h> 57#include <signal.h> 58#include <stddef.h> 59#include <stdio.h> 60#include <stdlib.h> 61#include <string.h> 62#include <time.h> 63#include <unistd.h> 64 65#include "truss.h" 66#include "syscall.h" 67#include "extern.h" 68 69#include "syscalls.h" 70 71static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]); 72 73/* 74 * This is what this particular file uses to keep track of a system call. 75 * It is probably not quite sufficient -- I can probably use the same 76 * structure for the various syscall personalities, and I also probably 77 * need to nest system calls (for signal handlers). 78 * 79 * 'struct syscall' describes the system call; it may be NULL, however, 80 * if we don't know about this particular system call yet. 81 */ 82struct freebsd_syscall { 83 struct syscall *sc; 84 const char *name; 85 int number; 86 unsigned long *args; 87 int nargs; /* number of arguments -- *not* number of words! */ 88 char **s_args; /* the printable arguments */ 89}; 90 91static struct freebsd_syscall * 92alloc_fsc(void) 93{ 94 95 return (malloc(sizeof(struct freebsd_syscall))); 96} 97 98/* Clear up and free parts of the fsc structure. */ 99static void 100free_fsc(struct freebsd_syscall *fsc) 101{ 102 int i; 103 104 free(fsc->args); 105 if (fsc->s_args) { 106 for (i = 0; i < fsc->nargs; i++) 107 free(fsc->s_args[i]); 108 free(fsc->s_args); 109 } 110 free(fsc); 111} 112 113/* 114 * Called when a process has entered a system call. nargs is the 115 * number of words, not number of arguments (a necessary distinction 116 * in some cases). Note that if the STOPEVENT() code in sparc64/sparc64/trap.c 117 * is ever changed these functions need to keep up. 118 */ 119 120void 121mips_syscall_entry(struct trussinfo *trussinfo, int nargs) 122{ 123 struct ptrace_io_desc iorequest; 124 struct reg regs; 125 struct freebsd_syscall *fsc; 126 struct syscall *sc; 127 lwpid_t tid; 128 int i, syscall_num; 129 int indir; /* indirect system call */ 130 131 tid = trussinfo->curthread->tid; 132 133 if (ptrace(PT_GETREGS, tid, (caddr_t)®s, 0) < 0) { 134 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); 135 return; 136 } 137 138 indir = 0; 139 syscall_num = regs.r_regs[V0]; 140 if (syscall_num == SYS_syscall) { 141 indir = 1; 142 syscall_num = regs.r_regs[A0]; 143 } 144 145 fsc = alloc_fsc(); 146 if (fsc == NULL) 147 return; 148 fsc->number = syscall_num; 149 fsc->name = (syscall_num < 0 || syscall_num >= nsyscalls) ? 150 NULL : syscallnames[syscall_num]; 151 if (!fsc->name) { 152 fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n", 153 syscall_num); 154 } 155 156 if (fsc->name && (trussinfo->flags & FOLLOWFORKS) && 157 (strcmp(fsc->name, "fork") == 0 || 158 strcmp(fsc->name, "rfork") == 0 || 159 strcmp(fsc->name, "vfork") == 0)) 160 trussinfo->curthread->in_fork = 1; 161 162 if (nargs == 0) 163 return; 164 165 fsc->args = malloc((1 + nargs) * sizeof(unsigned long)); 166#if 0 // XXX 167 iorequest.piod_op = PIOD_READ_D; 168 iorequest.piod_offs = (void *)parm_offset; 169 iorequest.piod_addr = fsc->args; 170 iorequest.piod_len = (1 + nargs) * sizeof(unsigned long); 171 ptrace(PT_IO, tid, (caddr_t)&iorequest, 0); 172 if (iorequest.piod_len == 0) 173 return; 174#else 175 iorequest.piod_op = PIOD_READ_D; 176#endif 177 178 switch (nargs) { 179 default: 180 /* 181 * The OS doesn't seem to allow more than 10 words of 182 * parameters (yay!). So we shouldn't be here. 183 */ 184 warn("More than 10 words (%d) of arguments!\n", nargs); 185 break; 186 case 10: 187 case 9: 188 case 8: 189 case 7: 190 case 6: 191 case 5: 192 /* 193 * If there are 7-10 words of arguments, they are placed 194 * on the stack, as is normal for other processors. 195 * The fall-through for all of these is deliberate!!! 196 */ 197 // XXX BAD constant used here 198 iorequest.piod_op = PIOD_READ_D; 199 iorequest.piod_offs = (void *)(regs.r_regs[SP] + 200 4 * sizeof(uint32_t)); 201 iorequest.piod_addr = &fsc->args[4]; 202 iorequest.piod_len = (nargs - 4) * sizeof(fsc->args[0]); 203 ptrace(PT_IO, tid, (caddr_t)&iorequest, 0); 204 if (iorequest.piod_len == 0) 205 return; 206 case 4: fsc->args[3] = regs.r_regs[A3]; 207 case 3: fsc->args[2] = regs.r_regs[A2]; 208 case 2: fsc->args[1] = regs.r_regs[A1]; 209 case 1: fsc->args[0] = regs.r_regs[A0]; 210 case 0: break; 211 } 212 if (indir) { 213 memmove(&fsc->args[0], &fsc->args[1], 214 (nargs - 1) * sizeof(fsc->args[0])); 215 } 216 217 sc = get_syscall(fsc->name); 218 if (sc) 219 fsc->nargs = sc->nargs; 220 else { 221#if DEBUG 222 fprintf(trussinfo->outfile, "unknown syscall %s -- setting " 223 "args to %d\n", fsc->name, nargs); 224#endif 225 fsc->nargs = nargs; 226 } 227 228 fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *)); 229 fsc->sc = sc; 230 231 /* 232 * At this point, we set up the system call arguments. 233 * We ignore any OUT ones, however -- those are arguments that 234 * are set by the system call, and so are probably meaningless 235 * now. This doesn't currently support arguments that are 236 * passed in *and* out, however. 237 */ 238 239 if (fsc->name) { 240#if DEBUG 241 fprintf(stderr, "syscall %s(", fsc->name); 242#endif 243 for (i = 0; i < fsc->nargs; i++) { 244#if DEBUG 245 fprintf(stderr, "0x%x%s", sc ? 246 fsc->args[sc->args[i].offset] : fsc->args[i], 247 i < (fsc->nargs - 1) ? "," : ""); 248#endif 249 if (sc && !(sc->args[i].type & OUT)) { 250 fsc->s_args[i] = print_arg(&sc->args[i], 251 fsc->args, 0, trussinfo); 252 } 253 } 254#if DEBUG 255 fprintf(stderr, ")\n"); 256#endif 257 } 258 259#if DEBUG 260 fprintf(trussinfo->outfile, "\n"); 261#endif 262 263 if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 || 264 strcmp(fsc->name, "exit") == 0)) { 265 /* 266 * XXX 267 * This could be done in a more general 268 * manner but it still wouldn't be very pretty. 269 */ 270 if (strcmp(fsc->name, "execve") == 0) { 271 if ((trussinfo->flags & EXECVEARGS) == 0) { 272 if (fsc->s_args[1]) { 273 free(fsc->s_args[1]); 274 fsc->s_args[1] = NULL; 275 } 276 } 277 if ((trussinfo->flags & EXECVEENVS) == 0) { 278 if (fsc->s_args[2]) { 279 free(fsc->s_args[2]); 280 fsc->s_args[2] = NULL; 281 } 282 } 283 } 284 } 285 trussinfo->curthread->fsc = fsc; 286} 287 288/* 289 * And when the system call is done, we handle it here. 290 * Currently, no attempt is made to ensure that the system calls 291 * match -- this needs to be fixed (and is, in fact, why S_SCX includes 292 * the system call number instead of, say, an error status). 293 */ 294 295long 296mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused) 297{ 298 struct reg regs; 299 struct freebsd_syscall *fsc; 300 struct syscall *sc; 301 lwpid_t tid; 302 long retval; 303 int errorp, i; 304 305 if (trussinfo->curthread->fsc == NULL) 306 return (-1); 307 308 tid = trussinfo->curthread->tid; 309 310 if (ptrace(PT_GETREGS, tid, (caddr_t)®s, 0) < 0) { 311 fprintf(trussinfo->outfile, "\n"); 312 return (-1); 313 } 314 315 retval = regs.r_regs[V0]; 316 errorp = !!regs.r_regs[A3]; 317 318 /* 319 * This code, while simpler than the initial versions I used, could 320 * stand some significant cleaning. 321 */ 322 323 fsc = trussinfo->curthread->fsc; 324 sc = fsc->sc; 325 if (!sc) { 326 for (i = 0; i < fsc->nargs; i++) 327 asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]); 328 } else { 329 /* 330 * Here, we only look for arguments that have OUT masked in -- 331 * otherwise, they were handled in the syscall_entry function. 332 */ 333 for (i = 0; i < sc->nargs; i++) { 334 char *temp; 335 if (sc->args[i].type & OUT) { 336 /* 337 * If an error occurred, then don't bother 338 * getting the data; it may not be valid. 339 */ 340 if (errorp) { 341 asprintf(&temp, "0x%lx", 342 fsc->args[sc->args[i].offset]); 343 } else { 344 temp = print_arg(&sc->args[i], 345 fsc->args, retval, trussinfo); 346 } 347 fsc->s_args[i] = temp; 348 } 349 } 350 } 351 352 if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 || 353 strcmp(fsc->name, "exit") == 0)) 354 trussinfo->curthread->in_syscall = 1; 355 356 /* 357 * It would probably be a good idea to merge the error handling, 358 * but that complicates things considerably. 359 */ 360 361 print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp, 362 retval, fsc->sc); 363 free_fsc(fsc); 364 365 return (retval); 366} 367