systrace.c revision 269272
1258578Shrs/* 2258578Shrs * CDDL HEADER START 3258578Shrs * 48870Srgrimes * The contents of this file are subject to the terms of the 5258578Shrs * Common Development and Distribution License (the "License"). 6258578Shrs * You may not use this file except in compliance with the License. 7258578Shrs * 8258578Shrs * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9258578Shrs * or http://www.opensolaris.org/os/licensing. 10258578Shrs * See the License for the specific language governing permissions 11258578Shrs * and limitations under the License. 12258578Shrs * 13258578Shrs * When distributing Covered Code, include this CDDL HEADER in each 14258578Shrs * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15258578Shrs * If applicable, add the following below this CDDL HEADER, with the 16258578Shrs * fields enclosed by brackets "[]" replaced with your own identifying 17258578Shrs * information: Portions Copyright [yyyy] [name of copyright owner] 18258578Shrs * 19258578Shrs * CDDL HEADER END 20258578Shrs * 21258578Shrs * Portions Copyright 2006-2008 John Birrell jb@freebsd.org 22258578Shrs * 23258578Shrs * $FreeBSD: stable/10/sys/cddl/dev/systrace/systrace.c 269272 2014-07-29 22:26:41Z markj $ 24258578Shrs * 25258578Shrs */ 26258578Shrs 271901Swollman/* 281901Swollman * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 291901Swollman * Use is subject to license terms. 30136581Sobrien */ 3174462Salfred 321901Swollman#include <sys/cdefs.h> 3392990Sobrien#include <sys/param.h> 3492990Sobrien#include <sys/systm.h> 351901Swollman#include <sys/conf.h> 361901Swollman#include <sys/cpuvar.h> 371901Swollman#include <sys/fcntl.h> 381901Swollman#include <sys/filio.h> 391901Swollman#include <sys/kdb.h> 401901Swollman#include <sys/kernel.h> 411901Swollman#include <sys/kmem.h> 421901Swollman#include <sys/kthread.h> 431901Swollman#include <sys/limits.h> 441901Swollman#include <sys/linker.h> 451901Swollman#include <sys/lock.h> 461901Swollman#include <sys/malloc.h> 4774462Salfred#include <sys/module.h> 4874462Salfred#include <sys/mutex.h> 491901Swollman#include <sys/poll.h> 5011666Sphk#include <sys/proc.h> 5174462Salfred#include <sys/selinfo.h> 521901Swollman#include <sys/smp.h> 5374462Salfred#include <sys/sysproto.h> 541901Swollman#include <sys/sysent.h> 551901Swollman#include <sys/uio.h> 561901Swollman#include <sys/unistd.h> 571901Swollman#include <machine/stdarg.h> 581901Swollman 59288113Srodrigc#include <sys/dtrace.h> 601901Swollman 6174462Salfred#ifdef LINUX_SYSTRACE 621901Swollman#if defined(__amd64__) 6374462Salfred#include <amd64/linux32/linux.h> 6474462Salfred#include <amd64/linux32/linux32_proto.h> 651901Swollman#include <amd64/linux32/linux32_syscalls.c> 661901Swollman#include <amd64/linux32/linux32_systrace_args.c> 671901Swollman#define MODNAME "linux32" 68241181Spfg#elif defined(__i386__) 691901Swollman#include <i386/linux/linux.h> 701901Swollman#include <i386/linux/linux_proto.h> 7174462Salfred#include <i386/linux/linux_syscalls.c> 7274462Salfred#include <i386/linux/linux_systrace_args.c> 731901Swollman#define MODNAME "linux" 7474462Salfred#else 7574462Salfred#error Only i386 and amd64 are supported. 7674462Salfred#endif 771901Swollmanextern struct sysent linux_sysent[]; 781901Swollman#define MAXSYSCALL LINUX_SYS_MAXSYSCALL 791901Swollman#define SYSCALLNAMES linux_syscallnames 801901Swollman#define SYSENT linux_sysent 811901Swollman#elif defined(FREEBSD32_SYSTRACE) 821901Swollman/* 831901Swollman * The syscall arguments are processed into a DTrace argument array 841901Swollman * using a generated function. See sys/kern/makesyscalls.sh. 8574462Salfred */ 8674462Salfred#include <compat/freebsd32/freebsd32_proto.h> 871901Swollman#include <compat/freebsd32/freebsd32_util.h> 881901Swollman#include <compat/freebsd32/freebsd32_syscall.h> 891901Swollman#include <compat/freebsd32/freebsd32_systrace_args.c> 901901Swollmanextern const char *freebsd32_syscallnames[]; 9174462Salfred#define MODNAME "freebsd32" 921901Swollman#define MAXSYSCALL FREEBSD32_SYS_MAXSYSCALL 931901Swollman#define SYSCALLNAMES freebsd32_syscallnames 9421088Speter#define SYSENT freebsd32_sysent 9574462Salfred#else 9674462Salfred/* 9774462Salfred * The syscall arguments are processed into a DTrace argument array 981901Swollman * using a generated function. See sys/kern/makesyscalls.sh. 991901Swollman */ 1001901Swollman#include <sys/syscall.h> 1011901Swollman#include <kern/systrace_args.c> 1021901Swollman#define MODNAME "freebsd" 1031901Swollman#define MAXSYSCALL SYS_MAXSYSCALL 10474462Salfred#define SYSCALLNAMES syscallnames 1051901Swollman#define SYSENT sysent 1061901Swollman#endif 1071901Swollman 1081901Swollman#define PROVNAME "syscall" 1091901Swollman#define DEVNAME "dtrace/systrace/" MODNAME 1101901Swollman 11174462Salfred#define SYSTRACE_ARTIFICIAL_FRAMES 1 11274462Salfred 1131901Swollman#define SYSTRACE_SHIFT 16 1141901Swollman#define SYSTRACE_ISENTRY(x) ((int)(x) >> SYSTRACE_SHIFT) 1151901Swollman#define SYSTRACE_SYSNUM(x) ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1)) 1161901Swollman#define SYSTRACE_ENTRY(id) ((1 << SYSTRACE_SHIFT) | (id)) 1171901Swollman#define SYSTRACE_RETURN(id) (id) 1181901Swollman 1191901Swollman#if ((1 << SYSTRACE_SHIFT) <= MAXSYSCALL) 1201901Swollman#error 1 << SYSTRACE_SHIFT must exceed number of system calls 1211901Swollman#endif 12226221Swpaul 12374462Salfredstatic d_open_t systrace_open; 12426221Swpaulstatic int systrace_unload(void); 12574462Salfredstatic void systrace_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *); 12626221Swpaulstatic void systrace_provide(void *, dtrace_probedesc_t *); 12774462Salfredstatic void systrace_destroy(void *, dtrace_id_t, void *); 12826221Swpaulstatic void systrace_enable(void *, dtrace_id_t, void *); 12974462Salfredstatic void systrace_disable(void *, dtrace_id_t, void *); 13026221Swpaulstatic void systrace_load(void *); 13126221Swpaul 13226221Swpaulstatic struct cdevsw systrace_cdevsw = { 13326221Swpaul .d_version = D_VERSION, 13426221Swpaul .d_open = systrace_open, 1351901Swollman#ifdef LINUX_SYSTRACE 1361901Swollman .d_name = "systrace_" MODNAME, 1371901Swollman#else 1381901Swollman .d_name = "systrace", 1391901Swollman#endif 1401901Swollman}; 1411901Swollman 1421901Swollmanstatic union { 1431901Swollman const char **p_constnames; 1441901Swollman char **pp_syscallnames; 1451901Swollman} uglyhack = { SYSCALLNAMES }; 1461901Swollman 14774462Salfredstatic dtrace_pattr_t systrace_attr = { 148288113Srodrigc{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 1491901Swollman{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1501901Swollman{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 1511901Swollman{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 152{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 153}; 154 155static dtrace_pops_t systrace_pops = { 156 systrace_provide, 157 NULL, 158 systrace_enable, 159 systrace_disable, 160 NULL, 161 NULL, 162 systrace_getargdesc, 163 NULL, 164 NULL, 165 systrace_destroy 166}; 167 168static struct cdev *systrace_cdev; 169static dtrace_provider_id_t systrace_id; 170 171typedef void (*systrace_dtrace_probe_t)(dtrace_id_t, uintptr_t, uintptr_t, 172 uintptr_t, uintptr_t, uintptr_t, uintptr_t, uintptr_t, uintptr_t); 173 174#if !defined(LINUX_SYSTRACE) 175/* 176 * Probe callback function. 177 * 178 * Note: This function is called for _all_ syscalls, regardless of which sysent 179 * array the syscall comes from. It could be a standard syscall or a 180 * compat syscall from something like Linux. 181 */ 182static void 183systrace_probe(u_int32_t id, int sysnum, struct sysent *sysent, void *params, 184 int ret) 185{ 186 systrace_dtrace_probe_t probe; 187 int n_args = 0; 188 u_int64_t uargs[8]; 189 190 memset(uargs, 0, sizeof(uargs)); 191 /* 192 * Check if this syscall has an argument conversion function 193 * registered. 194 */ 195 if (params && sysent->sy_systrace_args_func != NULL) { 196 /* 197 * Convert the syscall parameters using the registered 198 * function. 199 */ 200 (*sysent->sy_systrace_args_func)(sysnum, params, uargs, &n_args); 201 } else if (params) { 202 /* 203 * Use the built-in system call argument conversion 204 * function to translate the syscall structure fields 205 * into the array of 64-bit values that DTrace 206 * expects. 207 */ 208 systrace_args(sysnum, params, uargs, &n_args); 209 } else { 210 /* 211 * Since params is NULL, this is a 'return' probe. 212 * Set arg0 and arg1 as the return value of this syscall. 213 */ 214 uargs[0] = uargs[1] = ret; 215 } 216 217 /* Process the probe using the converted argments. */ 218 probe = (systrace_dtrace_probe_t)dtrace_probe; 219 probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4], uargs[5], 220 uargs[6], uargs[7]); 221} 222 223#endif 224 225static void 226systrace_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc) 227{ 228 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 229 230 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 231 systrace_entry_setargdesc(sysnum, desc->dtargd_ndx, 232 desc->dtargd_native, sizeof(desc->dtargd_native)); 233 else 234 systrace_return_setargdesc(sysnum, desc->dtargd_ndx, 235 desc->dtargd_native, sizeof(desc->dtargd_native)); 236 237 if (desc->dtargd_native[0] == '\0') 238 desc->dtargd_ndx = DTRACE_ARGNONE; 239 240 return; 241} 242 243static void 244systrace_provide(void *arg, dtrace_probedesc_t *desc) 245{ 246 int i; 247 248 if (desc != NULL) 249 return; 250 251 for (i = 0; i < MAXSYSCALL; i++) { 252 if (dtrace_probe_lookup(systrace_id, MODNAME, 253 uglyhack.pp_syscallnames[i], "entry") != 0) 254 continue; 255 256 (void) dtrace_probe_create(systrace_id, MODNAME, uglyhack.pp_syscallnames[i], 257 "entry", SYSTRACE_ARTIFICIAL_FRAMES, 258 (void *)((uintptr_t)SYSTRACE_ENTRY(i))); 259 (void) dtrace_probe_create(systrace_id, MODNAME, uglyhack.pp_syscallnames[i], 260 "return", SYSTRACE_ARTIFICIAL_FRAMES, 261 (void *)((uintptr_t)SYSTRACE_RETURN(i))); 262 } 263} 264 265static void 266systrace_destroy(void *arg, dtrace_id_t id, void *parg) 267{ 268#ifdef DEBUG 269 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 270 271 /* 272 * There's nothing to do here but assert that we have actually been 273 * disabled. 274 */ 275 if (SYSTRACE_ISENTRY((uintptr_t)parg)) { 276 ASSERT(sysent[sysnum].sy_entry == 0); 277 } else { 278 ASSERT(sysent[sysnum].sy_return == 0); 279 } 280#endif 281} 282 283static void 284systrace_enable(void *arg, dtrace_id_t id, void *parg) 285{ 286 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 287 288 if (SYSENT[sysnum].sy_systrace_args_func == NULL) 289 SYSENT[sysnum].sy_systrace_args_func = systrace_args; 290 291 if (SYSTRACE_ISENTRY((uintptr_t)parg)) 292 SYSENT[sysnum].sy_entry = id; 293 else 294 SYSENT[sysnum].sy_return = id; 295} 296 297static void 298systrace_disable(void *arg, dtrace_id_t id, void *parg) 299{ 300 int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg); 301 302 SYSENT[sysnum].sy_entry = 0; 303 SYSENT[sysnum].sy_return = 0; 304} 305 306static void 307systrace_load(void *dummy) 308{ 309 /* Create the /dev/dtrace/systrace entry. */ 310 systrace_cdev = make_dev(&systrace_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 311 DEVNAME); 312 313 if (dtrace_register(PROVNAME, &systrace_attr, DTRACE_PRIV_USER, 314 NULL, &systrace_pops, NULL, &systrace_id) != 0) 315 return; 316 317#if !defined(LINUX_SYSTRACE) 318 systrace_probe_func = systrace_probe; 319#endif 320} 321 322 323static int 324systrace_unload() 325{ 326 int error = 0; 327 328 if ((error = dtrace_unregister(systrace_id)) != 0) 329 return (error); 330 331#if !defined(LINUX_SYSTRACE) 332 systrace_probe_func = NULL; 333#endif 334 335 destroy_dev(systrace_cdev); 336 337 return (error); 338} 339 340static int 341systrace_modevent(module_t mod __unused, int type, void *data __unused) 342{ 343 int error = 0; 344 345 switch (type) { 346 case MOD_LOAD: 347 break; 348 349 case MOD_UNLOAD: 350 break; 351 352 case MOD_SHUTDOWN: 353 break; 354 355 default: 356 error = EOPNOTSUPP; 357 break; 358 359 } 360 return (error); 361} 362 363static int 364systrace_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused) 365{ 366 return (0); 367} 368 369SYSINIT(systrace_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, systrace_load, NULL); 370SYSUNINIT(systrace_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, systrace_unload, NULL); 371 372#ifdef LINUX_SYSTRACE 373DEV_MODULE(systrace_linux32, systrace_modevent, NULL); 374MODULE_VERSION(systrace_linux32, 1); 375MODULE_DEPEND(systrace_linux32, linux, 1, 1, 1); 376MODULE_DEPEND(systrace_linux32, dtrace, 1, 1, 1); 377MODULE_DEPEND(systrace_linux32, opensolaris, 1, 1, 1); 378#elif defined(FREEBSD32_SYSTRACE) 379DEV_MODULE(systrace_freebsd32, systrace_modevent, NULL); 380MODULE_VERSION(systrace_freebsd32, 1); 381MODULE_DEPEND(systrace_freebsd32, dtrace, 1, 1, 1); 382MODULE_DEPEND(systrace_freebsd32, opensolaris, 1, 1, 1); 383#else 384DEV_MODULE(systrace, systrace_modevent, NULL); 385MODULE_VERSION(systrace, 1); 386MODULE_DEPEND(systrace, dtrace, 1, 1, 1); 387MODULE_DEPEND(systrace, opensolaris, 1, 1, 1); 388#endif 389