mips-fbsd.c revision 286789
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/10/usr.bin/truss/mips-fbsd.c 286789 2015-08-14 21:44:42Z emaste $"; 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, "pdfork") == 0 || 159 strcmp(fsc->name, "rfork") == 0 || 160 strcmp(fsc->name, "vfork") == 0)) 161 trussinfo->curthread->in_fork = 1; 162 163 if (nargs == 0) 164 return; 165 166 fsc->args = malloc((1 + nargs) * sizeof(unsigned long)); 167#if 0 // XXX 168 iorequest.piod_op = PIOD_READ_D; 169 iorequest.piod_offs = (void *)parm_offset; 170 iorequest.piod_addr = fsc->args; 171 iorequest.piod_len = (1 + nargs) * sizeof(unsigned long); 172 ptrace(PT_IO, tid, (caddr_t)&iorequest, 0); 173 if (iorequest.piod_len == 0) 174 return; 175#else 176 iorequest.piod_op = PIOD_READ_D; 177#endif 178 179 switch (nargs) { 180 default: 181 /* 182 * The OS doesn't seem to allow more than 10 words of 183 * parameters (yay!). So we shouldn't be here. 184 */ 185 warn("More than 10 words (%d) of arguments!\n", nargs); 186 break; 187 case 10: 188 case 9: 189 case 8: 190 case 7: 191 case 6: 192 case 5: 193 /* 194 * If there are 7-10 words of arguments, they are placed 195 * on the stack, as is normal for other processors. 196 * The fall-through for all of these is deliberate!!! 197 */ 198 // XXX BAD constant used here 199 iorequest.piod_op = PIOD_READ_D; 200 iorequest.piod_offs = (void *)(regs.r_regs[SP] + 201 4 * sizeof(uint32_t)); 202 iorequest.piod_addr = &fsc->args[4]; 203 iorequest.piod_len = (nargs - 4) * sizeof(fsc->args[0]); 204 ptrace(PT_IO, tid, (caddr_t)&iorequest, 0); 205 if (iorequest.piod_len == 0) 206 return; 207 case 4: fsc->args[3] = regs.r_regs[A3]; 208 case 3: fsc->args[2] = regs.r_regs[A2]; 209 case 2: fsc->args[1] = regs.r_regs[A1]; 210 case 1: fsc->args[0] = regs.r_regs[A0]; 211 case 0: break; 212 } 213 if (indir) { 214 memmove(&fsc->args[0], &fsc->args[1], 215 (nargs - 1) * sizeof(fsc->args[0])); 216 } 217 218 sc = get_syscall(fsc->name); 219 if (sc) 220 fsc->nargs = sc->nargs; 221 else { 222#if DEBUG 223 fprintf(trussinfo->outfile, "unknown syscall %s -- setting " 224 "args to %d\n", fsc->name, nargs); 225#endif 226 fsc->nargs = nargs; 227 } 228 229 fsc->s_args = calloc(1, (1 + fsc->nargs) * sizeof(char *)); 230 fsc->sc = sc; 231 232 /* 233 * At this point, we set up the system call arguments. 234 * We ignore any OUT ones, however -- those are arguments that 235 * are set by the system call, and so are probably meaningless 236 * now. This doesn't currently support arguments that are 237 * passed in *and* out, however. 238 */ 239 240 if (fsc->name) { 241#if DEBUG 242 fprintf(stderr, "syscall %s(", fsc->name); 243#endif 244 for (i = 0; i < fsc->nargs; i++) { 245#if DEBUG 246 fprintf(stderr, "0x%x%s", sc ? 247 fsc->args[sc->args[i].offset] : fsc->args[i], 248 i < (fsc->nargs - 1) ? "," : ""); 249#endif 250 if (sc && !(sc->args[i].type & OUT)) { 251 fsc->s_args[i] = print_arg(&sc->args[i], 252 fsc->args, 0, trussinfo); 253 } 254 } 255#if DEBUG 256 fprintf(stderr, ")\n"); 257#endif 258 } 259 260#if DEBUG 261 fprintf(trussinfo->outfile, "\n"); 262#endif 263 264 if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 || 265 strcmp(fsc->name, "exit") == 0)) { 266 /* 267 * XXX 268 * This could be done in a more general 269 * manner but it still wouldn't be very pretty. 270 */ 271 if (strcmp(fsc->name, "execve") == 0) { 272 if ((trussinfo->flags & EXECVEARGS) == 0) { 273 if (fsc->s_args[1]) { 274 free(fsc->s_args[1]); 275 fsc->s_args[1] = NULL; 276 } 277 } 278 if ((trussinfo->flags & EXECVEENVS) == 0) { 279 if (fsc->s_args[2]) { 280 free(fsc->s_args[2]); 281 fsc->s_args[2] = NULL; 282 } 283 } 284 } 285 } 286 trussinfo->curthread->fsc = fsc; 287} 288 289/* 290 * And when the system call is done, we handle it here. 291 * Currently, no attempt is made to ensure that the system calls 292 * match -- this needs to be fixed (and is, in fact, why S_SCX includes 293 * the system call number instead of, say, an error status). 294 */ 295 296long 297mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused) 298{ 299 struct reg regs; 300 struct freebsd_syscall *fsc; 301 struct syscall *sc; 302 lwpid_t tid; 303 long retval; 304 int errorp, i; 305 306 if (trussinfo->curthread->fsc == NULL) 307 return (-1); 308 309 tid = trussinfo->curthread->tid; 310 311 if (ptrace(PT_GETREGS, tid, (caddr_t)®s, 0) < 0) { 312 fprintf(trussinfo->outfile, "\n"); 313 return (-1); 314 } 315 316 retval = regs.r_regs[V0]; 317 errorp = !!regs.r_regs[A3]; 318 319 /* 320 * This code, while simpler than the initial versions I used, could 321 * stand some significant cleaning. 322 */ 323 324 fsc = trussinfo->curthread->fsc; 325 sc = fsc->sc; 326 if (!sc) { 327 for (i = 0; i < fsc->nargs; i++) 328 asprintf(&fsc->s_args[i], "0x%lx", fsc->args[i]); 329 } else { 330 /* 331 * Here, we only look for arguments that have OUT masked in -- 332 * otherwise, they were handled in the syscall_entry function. 333 */ 334 for (i = 0; i < sc->nargs; i++) { 335 char *temp; 336 if (sc->args[i].type & OUT) { 337 /* 338 * If an error occurred, then don't bother 339 * getting the data; it may not be valid. 340 */ 341 if (errorp) { 342 asprintf(&temp, "0x%lx", 343 fsc->args[sc->args[i].offset]); 344 } else { 345 temp = print_arg(&sc->args[i], 346 fsc->args, retval, trussinfo); 347 } 348 fsc->s_args[i] = temp; 349 } 350 } 351 } 352 353 if (fsc->name != NULL && (strcmp(fsc->name, "execve") == 0 || 354 strcmp(fsc->name, "exit") == 0)) 355 trussinfo->curthread->in_syscall = 1; 356 357 /* 358 * It would probably be a good idea to merge the error handling, 359 * but that complicates things considerably. 360 */ 361 362 print_syscall_ret(trussinfo, fsc->name, fsc->nargs, fsc->s_args, errorp, 363 retval, fsc->sc); 364 free_fsc(fsc); 365 366 return (retval); 367} 368