1 /* $NetBSD: systrace.c,v 1.12 2018/06/29 11:33:46 kamil Exp $ */ 2 3 /* 4 * CDDL HEADER START 5 * 6 * The contents of this file are subject to the terms of the 7 * Common Development and Distribution License (the "License"). 8 * You may not use this file except in compliance with the License. 9 * 10 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 11 * or http://www.opensolaris.org/os/licensing. 12 * See the License for the specific language governing permissions 13 * and limitations under the License. 14 * 15 * When distributing Covered Code, include this CDDL HEADER in each 16 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 17 * If applicable, add the following below this CDDL HEADER, with the 18 * fields enclosed by brackets "[]" replaced with your own identifying 19 * information: Portions Copyright [yyyy] [name of copyright owner] 20 * 21 * CDDL HEADER END 22 * 23 * Portions Copyright 2006-2008 John Birrell jb (at) freebsd.org 24 * 25 */ 26 27 /* 28 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 29 * Use is subject to license terms. 30 */ 31 32 #include <sys/cdefs.h> 33 /* __FBSDID("$FreeBSD: head/sys/cddl/dev/systrace/systrace.c 306220 2016-09-22 23:22:53Z markj $"); */ 34 35 #include <sys/proc.h> 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/conf.h> 39 #include <sys/cpuvar.h> 40 #include <sys/fcntl.h> 41 #include <sys/filio.h> 42 #include <sys/kernel.h> 43 #include <sys/kmem.h> 44 #include <sys/kthread.h> 45 #include <sys/syslimits.h> 46 #include <sys/linker.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/module.h> 50 #include <sys/mutex.h> 51 #include <sys/poll.h> 52 #include <sys/proc.h> 53 #include <sys/selinfo.h> 54 #include <sys/syscallargs.h> 55 #include <sys/uio.h> 56 #include <sys/unistd.h> 57 58 #include <sys/dtrace.h> 59 #include "dtrace_cddl.h" 60 61 #include "emultrace.h" 62 63 #define CONCAT(x,y) __CONCAT(x,y) 64 #define STRING(s) __STRING(s) 65 66 #ifdef __FreeBSD__ 67 #ifdef LINUX_SYSTRACE 68 #if defined(__amd64__) 69 #include <amd64/linux/linux.h> 70 #include <amd64/linux/linux_proto.h> 71 #include <amd64/linux/linux_syscalls.c> 72 #include <amd64/linux/linux_systrace_args.c> 73 #elif defined(__i386__) 74 #include <i386/linux/linux.h> 75 #include <i386/linux/linux_proto.h> 76 #include <i386/linux/linux_syscalls.c> 77 #include <i386/linux/linux_systrace_args.c> 78 #else 79 #error Only i386 and amd64 are supported. 80 #endif 81 #define MODNAME "linux" 82 extern struct sysent linux_sysent[]; 83 #define MAXSYSCALL LINUX_SYS_MAXSYSCALL 84 #define SYSCALLNAMES linux_syscallnames 85 #define SYSENT linux_sysent 86 #elif defined(LINUX32_SYSTRACE) 87 #if defined(__amd64__) 88 #include <amd64/linux32/linux.h> 89 #include <amd64/linux32/linux32_proto.h> 90 #include <amd64/linux32/linux32_syscalls.c> 91 #include <amd64/linux32/linux32_systrace_args.c> 92 #else 93 #error Only amd64 is supported. 94 #endif 95 #define MODNAME "linux32" 96 extern struct sysent linux32_sysent[]; 97 #define MAXSYSCALL LINUX32_SYS_MAXSYSCALL 98 #define SYSCALLNAMES linux32_syscallnames 99 #define SYSENT linux32_sysent 100 #elif defined(FREEBSD32_SYSTRACE) 101 /* 102 * The syscall arguments are processed into a DTrace argument array 103 * using a generated function. See sys/kern/makesyscalls.sh. 104 */ 105 #include <compat/freebsd32/freebsd32_proto.h> 106 #include <compat/freebsd32/freebsd32_util.h> 107 #include <compat/freebsd32/freebsd32_syscall.h> 108 #include <compat/freebsd32/freebsd32_systrace_args.c> 109 extern const char *freebsd32_syscallnames[]; 110 #define MODNAME "freebsd32" 111 #define MAXSYSCALL FREEBSD32_SYS_MAXSYSCALL 112 #define SYSCALLNAMES freebsd32_syscallnames 113 #define SYSENT freebsd32_sysent 114 #else 115 /* 116 * The syscall arguments are processed into a DTrace argument array 117 * using a generated function. See sys/kern/makesyscalls.sh. 118 */ 119 #include <sys/syscall.h> 120 #include <kern/systrace_args.c> 121 #define MODNAME "freebsd" 122 #define MAXSYSCALL SYS_MAXSYSCALL 123 #define SYSCALLNAMES syscallnames 124 #define SYSENT sysent 125 #define NATIVE_ABI 126 #endif 127 128 #define PROVNAME "syscall" 129 #define DEVNAME "dtrace/systrace/" MODNAME 130 #endif /* __FreeBSD__ */ 131 132 #ifdef __NetBSD__ 133 #include <sys/syscallargs.h> 134 135 #ifndef NATIVE 136 extern const char * const CONCAT(emulname,_syscallnames)[]; 137 extern const char * const CONCAT(alt,CONCAT(emulname,_syscallnames))[]; 138 extern struct sysent CONCAT(emulname,_sysent)[]; 139 #define MODNAME CONCAT(dtrace_syscall_,emulname) 140 #define MODDEP "dtrace_syscall,compat_" STRING(emulname) 141 #define MAXSYSCALL CONCAT(EMULNAME,_SYS_MAXSYSCALL) 142 #define SYSCALLNAMES CONCAT(emulname,_syscallnames) 143 #define ALTSYSCALLNAMES CONCAT(alt,CONCAT(emulname,_syscallnames)) 144 #define SYSENT CONCAT(emulname,_sysent) 145 #define PROVNAME STRING(emulname) "_syscall" 146 #else 147 extern const char * const syscallnames[]; 148 extern const char * const altsyscallnames[]; 149 #define MODNAME dtrace_syscall 150 #define MODDEP "dtrace" 151 #define MAXSYSCALL SYS_MAXSYSCALL 152 #define SYSCALLNAMES syscallnames 153 #define ALTSYSCALLNAMES altsyscallnames 154 #define SYSENT sysent 155 #define PROVNAME "syscall" 156 #endif 157 158 #define MODCMD CONCAT(MODNAME,_modcmd) 159 #define EMUL CONCAT(emul_,emulname) 160 extern struct emul EMUL; 161 #define curthread curlwp 162 #endif /* __NetBSD__ */ 163 164 #define SYSTRACE_ARTIFICIAL_FRAMES 1 165 166 #define SYSTRACE_SHIFT 16 167 #define SYSTRACE_ISENTRY(x) ((int)(x) >> SYSTRACE_SHIFT) 168 #define SYSTRACE_SYSNUM(x) ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1)) 169 #define SYSTRACE_ENTRY(id) ((1 << SYSTRACE_SHIFT) | (id)) 170 #define SYSTRACE_RETURN(id) (id) 171 172 #if ((1 << SYSTRACE_SHIFT) <= MAXSYSCALL) 173 #error 1 << SYSTRACE_SHIFT must exceed number of system calls 174 #endif 175 176 static int systrace_unload(void); 177 static void systrace_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *); 178 static uint64_t systrace_getargval(void *, dtrace_id_t, void *, int, int); 179 static void systrace_provide(void *, dtrace_probedesc_t *); 180 static void systrace_destroy(void *, dtrace_id_t, void *); 181 static int systrace_enable(void *, dtrace_id_t, void *); 182 static void systrace_disable(void *, dtrace_id_t, void *); 183 static void systrace_load(void *); 184 185 #ifdef __FreeBSD__ 186 static union { 187 const char **p_constnames; 188 char **pp_syscallnames; 189 } uglyhack = { SYSCALLNAMES }; 190 #endif 191 192 static dtrace_pattr_t systrace_attr = { 193 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 194 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 195 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 196 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 197 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 198 }; 199 200 static dtrace_pops_t systrace_pops = { 201 systrace_provide, 202 NULL, 203 systrace_enable, 204 systrace_disable, 205 NULL, 206 NULL, 207 systrace_getargdesc, 208 systrace_getargval, 209 NULL, 210 systrace_destroy 211 }; 212 213 static dtrace_provider_id_t systrace_id; 214 215 /* 216 * Probe callback function. 217 * 218 * Note: This function is called for _all_ syscalls, regardless of which sysent 219 * array the syscall comes from. It could be a standard syscall or a 220 * compat syscall from something like Linux. 221 */ 222 #ifdef __FreeBSD__ 223 #ifdef NATIVE_ABI 224 static void 225 systrace_probe(struct syscall_args *sa, enum systrace_probe_t type, int retval) 226 { 227 uint64_t uargs[nitems(sa->args)]; 228 dtrace_id_t id; 229 int n_args, sysnum; 230 231 sysnum = sa->code; 232 memset(uargs, 0, sizeof(uargs)); 233 234 if (type == SYSTRACE_ENTRY) { 235 if ((id = sa->callp->sy_entry) == DTRACE_IDNONE) 236 return; 237 238 if (sa->callp->sy_systrace_args_func != NULL) 239 /* 240 * Convert the syscall parameters using the registered 241 * function. 242 */ 243 (*sa->callp->sy_systrace_args_func)(sysnum, sa->args, 244 uargs, &n_args); 245 else 246 /* 247 * Use the built-in system call argument conversion 248 * function to translate the syscall structure fields 249 * into the array of 64-bit values that DTrace expects. 250 */ 251 systrace_args(sysnum, sa->args, uargs, &n_args); 252 /* 253 * Save probe arguments now so that we can retrieve them if 254 * the getargval method is called from further down the stack. 255 */ 256 curthread->t_dtrace_systrace_args = uargs; 257 } else { 258 if ((id = sa->callp->sy_return) == DTRACE_IDNONE) 259 return; 260 261 curthread->t_dtrace_systrace_args = NULL; 262 /* Set arg0 and arg1 as the return value of this syscall. */ 263 uargs[0] = uargs[1] = retval; 264 } 265 266 /* Process the probe using the converted argments. */ 267 dtrace_probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4]); 268 } 269 #endif /* NATIVE_ABI */ 270 #endif /* __FreeBSD__ */ 271 272 #ifdef __NetBSD__ 273 static void 274 systrace_probe(uint32_t id, register_t sysnum, const struct sysent *se, 275 const void *params, const register_t *ret, int error) 276 { 277 size_t n_args = 0; 278 uintptr_t uargs[SYS_MAXSYSARGS + 3]; 279 280 memset(uargs, 0, sizeof(uargs)); 281 if (ret == NULL) { 282 /* entry syscall, convert params */ 283 systrace_args(sysnum, params, uargs, &n_args); 284 } else { 285 /* return syscall, set values and params: */ 286 uargs[0] = ret[0]; 287 uargs[1] = ret[1]; 288 uargs[2] = error; 289 systrace_args(sysnum, params, uargs + 3, &n_args); 290 } 291 /* Process the probe using the converted argments. */ 292 /* XXX: fix for more arguments! */ 293 dtrace_probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4]); 294 } 295 #endif 296 297 static void 298 systrace_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc) 299 { 300 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 301 302 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 303 systrace_entry_setargdesc(sysnum, desc->dtargd_ndx, 304 desc->dtargd_native, sizeof(desc->dtargd_native)); 305 else 306 systrace_return_setargdesc(sysnum, desc->dtargd_ndx, 307 desc->dtargd_native, sizeof(desc->dtargd_native)); 308 309 if (desc->dtargd_native[0] == '\0') 310 desc->dtargd_ndx = DTRACE_ARGNONE; 311 } 312 313 static uint64_t 314 systrace_getargval(void *arg, dtrace_id_t id, void *parg, int argno, int aframes) 315 { 316 uint64_t *uargs; 317 318 uargs = curthread->t_dtrace_systrace_args; 319 if (uargs == NULL) 320 /* This is a return probe. */ 321 return (0); 322 #ifdef __FreeBSD__ 323 if (argno >= nitems(((struct syscall_args *)NULL)->args)) 324 return (0); 325 #endif 326 #ifdef __NetBSD__ 327 if (argno >= SYS_MAXSYSARGS) 328 return (0); 329 #endif 330 331 return (uargs[argno]); 332 } 333 334 static void 335 systrace_provide(void *arg, dtrace_probedesc_t *desc) 336 { 337 int i; 338 339 if (desc != NULL) 340 return; 341 342 for (i = 0; i < MAXSYSCALL; i++) { 343 #ifdef __FreeBSD__ 344 if (dtrace_probe_lookup(systrace_id, MODNAME, 345 uglyhack.pp_syscallnames[i], "entry") != 0) 346 continue; 347 348 (void)dtrace_probe_create(systrace_id, MODNAME, 349 uglyhack.pp_syscallnames[i], "entry", 350 SYSTRACE_ARTIFICIAL_FRAMES, 351 (void *)((uintptr_t)SYSTRACE_ENTRY(i))); 352 (void)dtrace_probe_create(systrace_id, MODNAME, 353 uglyhack.pp_syscallnames[i], "return", 354 SYSTRACE_ARTIFICIAL_FRAMES, 355 (void *)((uintptr_t)SYSTRACE_RETURN(i))); 356 #else 357 const char *name = ALTSYSCALLNAMES[i] ? ALTSYSCALLNAMES[i] : 358 SYSCALLNAMES[i]; 359 if (dtrace_probe_lookup(systrace_id, NULL, name, "entry") != 0) 360 continue; 361 362 (void) dtrace_probe_create(systrace_id, NULL, 363 name, "entry", SYSTRACE_ARTIFICIAL_FRAMES, 364 (void *)(intptr_t)SYSTRACE_ENTRY(i)); 365 (void) dtrace_probe_create(systrace_id, NULL, 366 name, "return", SYSTRACE_ARTIFICIAL_FRAMES, 367 (void *)(intptr_t)SYSTRACE_RETURN(i)); 368 #endif 369 } 370 } 371 372 static void 373 systrace_destroy(void *arg, dtrace_id_t id, void *parg) 374 { 375 #ifdef DEBUG 376 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 377 378 /* 379 * There's nothing to do here but assert that we have actually been 380 * disabled. 381 */ 382 if (SYSTRACE_ISENTRY((uintptr_t)parg)) { 383 ASSERT(sysent[sysnum].sy_entry == 0); 384 } else { 385 ASSERT(sysent[sysnum].sy_return == 0); 386 } 387 #endif 388 } 389 390 static int 391 systrace_enable(void *arg, dtrace_id_t id, void *parg) 392 { 393 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 394 395 #ifdef __FreeBSD__ 396 if (SYSENT[sysnum].sy_systrace_args_func == NULL) 397 SYSENT[sysnum].sy_systrace_args_func = systrace_args; 398 #endif 399 400 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 401 SYSENT[sysnum].sy_entry = id; 402 else 403 SYSENT[sysnum].sy_return = id; 404 405 return 0; 406 } 407 408 static void 409 systrace_disable(void *arg, dtrace_id_t id, void *parg) 410 { 411 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 412 413 SYSENT[sysnum].sy_entry = 0; 414 SYSENT[sysnum].sy_return = 0; 415 } 416 417 static void 418 systrace_load(void *dummy) 419 { 420 if (dtrace_register(PROVNAME, &systrace_attr, DTRACE_PRIV_USER, NULL, 421 &systrace_pops, NULL, &systrace_id) != 0) 422 return; 423 424 #ifdef NATIVE_ABI 425 systrace_probe_func = systrace_probe; 426 #endif 427 #ifdef __NetBSD__ 428 EMUL.e_dtrace_syscall = systrace_probe; 429 #endif 430 } 431 432 433 static int 434 systrace_unload() 435 { 436 int error; 437 438 #ifdef NATIVE_ABI 439 systrace_probe_func = NULL; 440 #endif 441 #ifdef __NetBSD__ 442 EMUL.e_dtrace_syscall = NULL; 443 #endif 444 445 if ((error = dtrace_unregister(systrace_id)) != 0) 446 return (error); 447 448 return error; 449 } 450 451 #ifdef __FreeBSD__ 452 static int 453 systrace_modevent(module_t mod __unused, int type, void *data __unused) 454 { 455 int error; 456 457 error = 0; 458 switch (type) { 459 case MOD_LOAD: 460 break; 461 462 case MOD_UNLOAD: 463 break; 464 465 case MOD_SHUTDOWN: 466 break; 467 468 default: 469 error = EOPNOTSUPP; 470 break; 471 472 } 473 return (error); 474 } 475 476 SYSINIT(systrace_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 477 systrace_load, NULL); 478 SYSUNINIT(systrace_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 479 systrace_unload, NULL); 480 481 #ifdef LINUX_SYSTRACE 482 DEV_MODULE(systrace_linux, systrace_modevent, NULL); 483 MODULE_VERSION(systrace_linux, 1); 484 #ifdef __amd64__ 485 MODULE_DEPEND(systrace_linux, linux64, 1, 1, 1); 486 #else 487 MODULE_DEPEND(systrace_linux, linux, 1, 1, 1); 488 #endif 489 MODULE_DEPEND(systrace_linux, dtrace, 1, 1, 1); 490 MODULE_DEPEND(systrace_linux, opensolaris, 1, 1, 1); 491 #elif defined(LINUX32_SYSTRACE) 492 DEV_MODULE(systrace_linux32, systrace_modevent, NULL); 493 MODULE_VERSION(systrace_linux32, 1); 494 MODULE_DEPEND(systrace_linux32, linux, 1, 1, 1); 495 MODULE_DEPEND(systrace_linux32, dtrace, 1, 1, 1); 496 MODULE_DEPEND(systrace_linux32, opensolaris, 1, 1, 1); 497 #elif defined(FREEBSD32_SYSTRACE) 498 DEV_MODULE(systrace_freebsd32, systrace_modevent, NULL); 499 MODULE_VERSION(systrace_freebsd32, 1); 500 MODULE_DEPEND(systrace_freebsd32, dtrace, 1, 1, 1); 501 MODULE_DEPEND(systrace_freebsd32, opensolaris, 1, 1, 1); 502 #else 503 DEV_MODULE(systrace, systrace_modevent, NULL); 504 MODULE_VERSION(systrace, 1); 505 MODULE_DEPEND(systrace, dtrace, 1, 1, 1); 506 MODULE_DEPEND(systrace, opensolaris, 1, 1, 1); 507 #endif 508 #endif /* __FreeBSD__ */ 509 510 #ifdef __NetBSD__ 511 512 static int 513 MODCMD(modcmd_t cmd, void *data) 514 { 515 switch (cmd) { 516 case MODULE_CMD_INIT: 517 systrace_load(NULL); 518 return 0; 519 520 case MODULE_CMD_FINI: 521 return systrace_unload(); 522 523 case MODULE_CMD_AUTOUNLOAD: 524 return EBUSY; 525 526 default: 527 return ENOTTY; 528 } 529 } 530 531 MODULE(MODULE_CLASS_MISC, MODNAME, MODDEP) 532 533 #endif /* __NetBSD__ */ 534
Indexes created Tue Feb 24 08:35:24 UTC 2026