mips-fbsd.c revision 192041
1/* 2 * Copryight 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: head/usr.bin/truss/mips-fbsd.c 192041 2009-05-13 13:00:52Z dds $"; 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 69static int cpid = -1; 70 71#include "syscalls.h" 72 73static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]); 74 75/* 76 * This is what this particular file uses to keep track of a system call. 77 * It is probably not quite sufficient -- I can probably use the same 78 * structure for the various syscall personalities, and I also probably 79 * need to nest system calls (for signal handlers). 80 * 81 * 'struct syscall' describes the system call; it may be NULL, however, 82 * if we don't know about this particular system call yet. 83 */ 84static struct freebsd_syscall { 85 struct syscall *sc; 86 const char *name; 87 int number; 88 unsigned long *args; 89 int nargs; /* number of arguments -- *not* number of words! */ 90 char **s_args; /* the printable arguments */ 91} fsc; 92 93/* Clear up and free parts of the fsc structure. */ 94static __inline void 95clear_fsc(void) { 96 if (fsc.args) { 97 free(fsc.args); 98 } 99 if (fsc.s_args) { 100 int i; 101 for (i = 0; i < fsc.nargs; i++) 102 if (fsc.s_args[i]) 103 free(fsc.s_args[i]); 104 free(fsc.s_args); 105 } 106 memset(&fsc, 0, sizeof(fsc)); 107} 108 109/* 110 * Called when a process has entered a system call. nargs is the 111 * number of words, not number of arguments (a necessary distinction 112 * in some cases). Note that if the STOPEVENT() code in sparc64/sparc64/trap.c 113 * is ever changed these functions need to keep up. 114 */ 115 116void 117mips_syscall_entry(struct trussinfo *trussinfo, int nargs) { 118 struct reg regs; 119 int syscall_num; 120 int i; 121 struct syscall *sc; 122 int indir = 0; /* indirect system call */ 123 struct ptrace_io_desc iorequest; 124 125 cpid = trussinfo->curthread->tid; 126 127 clear_fsc(); 128 129 if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) { 130 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); 131 return; 132 } 133 134 syscall_num = regs.r_regs[V0]; 135 if (syscall_num == SYS_syscall) { 136 indir = 1; 137 syscall_num = regs.r_regs[A0]; 138 } 139 140 fsc.number = syscall_num; 141 fsc.name = 142 (syscall_num < 0 || syscall_num > nsyscalls) ? NULL : syscallnames[syscall_num]; 143 if (!fsc.name) { 144 fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n", syscall_num); 145 } 146 147 if (fsc.name && (trussinfo->flags & FOLLOWFORKS) 148 && ((!strcmp(fsc.name, "fork") 149 || !strcmp(fsc.name, "rfork") 150 || !strcmp(fsc.name, "vfork")))) 151 { 152 trussinfo->curthread->in_fork = 1; 153 } 154 155 if (nargs == 0) 156 return; 157 158#if 0 // XXX 159 fsc.args = malloc((1+nargs) * sizeof(unsigned long)); 160 iorequest.piod_op = PIOD_READ_D; 161 iorequest.piod_offs = (void *)parm_offset; 162 iorequest.piod_addr = fsc.args; 163 iorequest.piod_len = (1+nargs) * sizeof(unsigned long); 164 ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0); 165 if (iorequest.piod_len == 0) 166 return; 167#else 168 iorequest.piod_op = PIOD_READ_D; 169#endif 170 171 switch (nargs) { 172 default: 173 /* 174 * The OS doesn't seem to allow more than 10 words of 175 * parameters (yay!). So we shouldn't be here. 176 */ 177 warn("More than 10 words (%d) of arguments!\n", nargs); 178 break; 179 case 10: case 9: case 8: case 7: case 6: case 5: 180 /* 181 * If there are 7-10 words of arguments, they are placed 182 * on the stack, as is normal for other processors. 183 * The fall-through for all of these is deliberate!!! 184 */ 185 // XXX BAD constant used here 186 iorequest.piod_op = PIOD_READ_D; 187 iorequest.piod_offs = (void *)(regs.r_regs[SP] + 4 * sizeof(uint32_t)); 188 iorequest.piod_addr = &fsc.args[4]; 189 iorequest.piod_len = (nargs - 4) * sizeof(fsc.args[0]); 190 ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0); 191 if (iorequest.piod_len == 0) return; 192 case 4: fsc.args[3] = regs.r_regs[A3]; 193 case 3: fsc.args[2] = regs.r_regs[A2]; 194 case 2: fsc.args[1] = regs.r_regs[A1]; 195 case 1: fsc.args[0] = regs.r_regs[A0]; 196 case 0: 197 break; 198 } 199 if (indir) { 200 memmove(&fsc.args[0], &fsc.args[1], (nargs-1) * sizeof(fsc.args[0])); 201 } 202 203 sc = get_syscall(fsc.name); 204 if (sc) { 205 fsc.nargs = sc->nargs; 206 } else { 207#if DEBUG 208 fprintf(trussinfo->outfile, "unknown syscall %s -- setting args to %d\n", 209 fsc.name, nargs); 210#endif 211 fsc.nargs = nargs; 212 } 213 214 fsc.s_args = malloc((1+fsc.nargs) * sizeof(char*)); 215 memset(fsc.s_args, 0, fsc.nargs * sizeof(char*)); 216 fsc.sc = sc; 217 218 /* 219 * At this point, we set up the system call arguments. 220 * We ignore any OUT ones, however -- those are arguments that 221 * are set by the system call, and so are probably meaningless 222 * now. This doesn't currently support arguments that are 223 * passed in *and* out, however. 224 */ 225 226 if (fsc.name) { 227 228#if DEBUG 229 fprintf(stderr, "syscall %s(", fsc.name); 230#endif 231 for (i = 0; i < fsc.nargs; i++) { 232#if DEBUG 233 fprintf(stderr, "0x%x%s", 234 sc 235 ? fsc.args[sc->args[i].offset] 236 : fsc.args[i], 237 i < (fsc.nargs - 1) ? "," : ""); 238#endif 239 if (sc && !(sc->args[i].type & OUT)) { 240 fsc.s_args[i] = print_arg(&sc->args[i], fsc.args, 0, trussinfo); 241 } 242 } 243#if DEBUG 244 fprintf(stderr, ")\n"); 245#endif 246 } 247 248#if DEBUG 249 fprintf(trussinfo->outfile, "\n"); 250#endif 251 252 if (fsc.name != NULL && 253 (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { 254 255 /* XXX 256 * This could be done in a more general 257 * manner but it still wouldn't be very pretty. 258 */ 259 if (!strcmp(fsc.name, "execve")) { 260 if ((trussinfo->flags & EXECVEARGS) == 0) 261 if (fsc.s_args[1]) { 262 free(fsc.s_args[1]); 263 fsc.s_args[1] = NULL; 264 } 265 if ((trussinfo->flags & EXECVEENVS) == 0) 266 if (fsc.s_args[2]) { 267 free(fsc.s_args[2]); 268 fsc.s_args[2] = NULL; 269 } 270 } 271 } 272 273 return; 274} 275 276/* 277 * And when the system call is done, we handle it here. 278 * Currently, no attempt is made to ensure that the system calls 279 * match -- this needs to be fixed (and is, in fact, why S_SCX includes 280 * the sytem call number instead of, say, an error status). 281 */ 282 283long 284mips_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused) { 285 struct reg regs; 286 long retval; 287 int i; 288 int errorp; 289 struct syscall *sc; 290 291 if (fsc.name == NULL) 292 return (-1); 293 cpid = trussinfo->curthread->tid; 294 295 if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) { 296 fprintf(trussinfo->outfile, "\n"); 297 return (-1); 298 } 299 retval = regs.r_regs[V0]; 300 errorp = !!regs.r_regs[A3]; 301 302 /* 303 * This code, while simpler than the initial versions I used, could 304 * stand some significant cleaning. 305 */ 306 307 sc = fsc.sc; 308 if (!sc) { 309 for (i = 0; i < fsc.nargs; i++) 310 asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]); 311 } else { 312 /* 313 * Here, we only look for arguments that have OUT masked in -- 314 * otherwise, they were handled in the syscall_entry function. 315 */ 316 for (i = 0; i < sc->nargs; i++) { 317 char *temp; 318 if (sc->args[i].type & OUT) { 319 /* 320 * If an error occurred, than don't bothe getting the data; 321 * it may not be valid. 322 */ 323 if (errorp) 324 asprintf(&temp, "0x%lx", fsc.args[sc->args[i].offset]); 325 else 326 temp = print_arg(&sc->args[i], fsc.args, retval, trussinfo); 327 fsc.s_args[i] = temp; 328 } 329 } 330 } 331 332 if (fsc.name != NULL && 333 (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { 334 trussinfo->curthread->in_syscall = 1; 335 } 336 /* 337 * It would probably be a good idea to merge the error handling, 338 * but that complicates things considerably. 339 */ 340 341 print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp, 342 retval, fsc.sc); 343 clear_fsc(); 344 345 return (retval); 346} 347