1 /* $NetBSD: setemul.c,v 1.32 2019/03/25 19:24:31 maxv Exp $ */ 2 3 /*- 4 * Copyright (c) 2000 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * Copyright (c) 1988, 1993 31 * The Regents of the University of California. All rights reserved. 32 * (c) UNIX System Laboratories, Inc. 33 * All or some portions of this file are derived from material licensed 34 * to the University of California by American Telephone and Telegraph 35 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 36 * the permission of UNIX System Laboratories, Inc. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. Neither the name of the University nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 */ 62 63 #include <sys/cdefs.h> 64 #ifndef lint 65 __RCSID("$NetBSD: setemul.c,v 1.32 2019/03/25 19:24:31 maxv Exp $"); 66 #endif /* not lint */ 67 68 #include <sys/param.h> 69 #include <sys/errno.h> 70 #include <sys/time.h> 71 #include <sys/queue.h> 72 73 #include <err.h> 74 #include <stdio.h> 75 #include <stdlib.h> 76 #include <string.h> 77 #include <unistd.h> 78 #include <vis.h> 79 80 #include "setemul.h" 81 82 #include <sys/syscall.h> 83 84 #include "../../sys/compat/netbsd32/netbsd32_syscall.h" 85 #include "../../sys/compat/freebsd/freebsd_syscall.h" 86 #include "../../sys/compat/linux/linux_syscall.h" 87 #include "../../sys/compat/linux32/linux32_syscall.h" 88 #include "../../sys/compat/sunos32/sunos32_syscall.h" 89 #include "../../sys/compat/sunos/sunos_syscall.h" 90 #include "../../sys/compat/ultrix/ultrix_syscall.h" 91 #ifdef __m68k__ 92 #include "../../sys/compat/aoutm68k/aoutm68k_syscall.h" 93 #endif 94 95 #define KTRACE 96 #include "../../sys/kern/syscalls.c" 97 98 #include "../../sys/compat/netbsd32/netbsd32_syscalls.c" 99 #include "../../sys/compat/freebsd/freebsd_syscalls.c" 100 #include "../../sys/compat/linux/linux_syscalls.c" 101 #include "../../sys/compat/linux32/linux32_syscalls.c" 102 #include "../../sys/compat/sunos/sunos_syscalls.c" 103 #include "../../sys/compat/sunos32/sunos32_syscalls.c" 104 #include "../../sys/compat/ultrix/ultrix_syscalls.c" 105 #ifdef __m68k__ 106 #include "../../sys/compat/aoutm68k/aoutm68k_syscalls.c" 107 #endif 108 109 #include "../../sys/compat/linux/common/linux_errno.c" 110 #undef KTRACE 111 112 #define SIGRTMIN 33 /* XXX */ 113 #include "../../sys/compat/linux/common/linux_signo.c" 114 115 #define NELEM(a) (sizeof(a) / sizeof(a[0])) 116 117 /* static */ 118 const struct emulation emulations[] = { 119 { "netbsd", syscallnames, SYS_MAXSYSCALL, 120 NULL, 0, 121 NULL, 0, 0 }, 122 123 { "netbsd32", netbsd32_syscallnames, SYS_MAXSYSCALL, 124 NULL, 0, 125 NULL, 0, EMUL_FLAG_NETBSD32 }, 126 127 { "freebsd", freebsd_syscallnames, FREEBSD_SYS_MAXSYSCALL, 128 NULL, 0, 129 NULL, 0, 0 }, 130 131 { "linux", linux_syscallnames, LINUX_SYS_MAXSYSCALL, 132 native_to_linux_errno, NELEM(native_to_linux_errno), 133 linux_to_native_signo, NSIG, 0 }, 134 135 { "linux32", linux32_syscallnames, LINUX32_SYS_MAXSYSCALL, 136 native_to_linux_errno, NELEM(native_to_linux_errno), 137 linux_to_native_signo, NSIG, EMUL_FLAG_NETBSD32 }, 138 139 { "sunos32", sunos32_syscallnames, SUNOS32_SYS_MAXSYSCALL, 140 NULL, 0, 141 NULL, 0, EMUL_FLAG_NETBSD32 }, 142 143 { "sunos", sunos_syscallnames, SUNOS_SYS_MAXSYSCALL, 144 NULL, 0, 145 NULL, 0, 0 }, 146 147 { "ultrix", ultrix_syscallnames, ULTRIX_SYS_MAXSYSCALL, 148 NULL, 0, 149 NULL, 0, 0 }, 150 151 #ifdef __m68k__ 152 { "aoutm68k", aoutm68k_syscallnames, AOUTM68K_SYS_MAXSYSCALL, 153 NULL, 0, 154 NULL, 0, 0 }, 155 #endif 156 157 { NULL, NULL, 0, 158 NULL, 0, 159 NULL, 0, 0 } 160 }; 161 162 struct emulation_ctx { 163 pid_t pid; 164 const struct emulation *emulation; 165 LIST_ENTRY(emulation_ctx) ctx_link; 166 }; 167 168 const struct emulation *cur_emul; 169 const struct emulation *prev_emul; 170 171 static const struct emulation *default_emul = &emulations[0]; 172 173 struct emulation_ctx *current_ctx; 174 static LIST_HEAD(, emulation_ctx) emul_ctx = 175 LIST_HEAD_INITIALIZER(emul_ctx); 176 177 static struct emulation_ctx *ectx_find(pid_t); 178 static void ectx_update(pid_t, const struct emulation *); 179 180 void 181 setemul(const char *name, pid_t pid, int update_ectx) 182 { 183 int i; 184 const struct emulation *match = NULL; 185 186 for (i = 0; emulations[i].name != NULL; i++) { 187 if (strcmp(emulations[i].name, name) == 0) { 188 match = &emulations[i]; 189 break; 190 } 191 } 192 193 if (!match) { 194 warnx("Emulation `%s' unknown", name); 195 return; 196 } 197 198 if (update_ectx) 199 ectx_update(pid, match); 200 else 201 default_emul = match; 202 203 if (cur_emul != NULL) 204 prev_emul = cur_emul; 205 else 206 prev_emul = match; 207 208 cur_emul = match; 209 } 210 211 /* 212 * Emulation context list is very simple chained list, not even hashed. 213 * We expect the number of separate traced contexts/processes to be 214 * fairly low, so it's not worth it to optimize this. 215 * MMMmmmm not when I use it, it is only bounded PID_MAX! 216 * Requeue looked up item at start of list to cache result since the 217 * trace file tendes to have a burst of calls for a single process. 218 */ 219 220 /* 221 * Find an emulation context appropriate for the given pid. 222 */ 223 static struct emulation_ctx * 224 ectx_find(pid_t pid) 225 { 226 struct emulation_ctx *ctx; 227 228 /* Find an existing entry */ 229 LIST_FOREACH(ctx, &emul_ctx, ctx_link) { 230 if (ctx->pid == pid) 231 break; 232 } 233 234 if (ctx == NULL) { 235 /* create entry with default emulation */ 236 ctx = malloc(sizeof *ctx); 237 if (ctx == NULL) 238 err(1, "malloc emul context"); 239 ctx->pid = pid; 240 ctx->emulation = default_emul; 241 242 /* chain into the list */ 243 LIST_INSERT_HEAD(&emul_ctx, ctx, ctx_link); 244 } else { 245 /* move entry to head to optimize lookup for syscall bursts */ 246 LIST_REMOVE(ctx, ctx_link); 247 LIST_INSERT_HEAD(&emul_ctx, ctx, ctx_link); 248 } 249 250 return ctx; 251 } 252 253 /* 254 * Update emulation context for given pid, or create new if no context 255 * for this pid exists. 256 */ 257 static void 258 ectx_update(pid_t pid, const struct emulation *emul) 259 { 260 struct emulation_ctx *ctx; 261 262 ctx = ectx_find(pid); 263 ctx->emulation = emul; 264 } 265 266 /* 267 * Ensure current emulation context is correct for given pid. 268 */ 269 void 270 ectx_sanify(pid_t pid) 271 { 272 struct emulation_ctx *ctx; 273 274 ctx = ectx_find(pid); 275 cur_emul = ctx->emulation; 276 } 277 278 /* 279 * Delete emulation context for current pid. 280 * (eg when tracing exit()) 281 * Defer delete just in case we've cached a pointer... 282 */ 283 void 284 ectx_delete(void) 285 { 286 static struct emulation_ctx *ctx = NULL; 287 288 if (ctx != NULL) 289 free(ctx); 290 291 /* 292 * The emulation for current syscall entry is always on HEAD, due 293 * to code in ectx_find(). 294 */ 295 ctx = LIST_FIRST(&emul_ctx); 296 297 if (ctx) 298 LIST_REMOVE(ctx, ctx_link); 299 } 300