1 /*- 2 * Copyright (c) 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static const char copyright[] = 36 "@(#) Copyright (c) 1992, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #if 0 41 #ifndef lint 42 static char sccsid[] = "@(#)gcore.c 8.2 (Berkeley) 9/23/93"; 43 #endif /* not lint */ 44 #endif 45 #include <sys/cdefs.h> 46 __FBSDID("$FreeBSD$"); 47 48 /* 49 * Originally written by Eric Cooper in Fall 1981. 50 * Inspired by a version 6 program by Len Levin, 1978. 51 * Several pieces of code lifted from Bill Joy's 4BSD ps. 52 * Most recently, hacked beyond recognition for 4.4BSD by Steven McCanne, 53 * Lawrence Berkeley Laboratory. 54 * 55 * Portions of this software were developed by the Computer Systems 56 * Engineering group at Lawrence Berkeley Laboratory under DARPA 57 * contract BG 91-66 and contributed to Berkeley. 58 */ 59 60 #include <sys/param.h> 61 #include <sys/time.h> 62 #include <sys/stat.h> 63 #include <sys/proc.h> 64 #include <sys/user.h> 65 #include <sys/sysctl.h> 66 67 #include <machine/elf.h> 68 #include <machine/vmparam.h> 69 70 #include <a.out.h> 71 #include <err.h> 72 #include <fcntl.h> 73 #include <kvm.h> 74 #include <limits.h> 75 #include <signal.h> 76 #include <stdio.h> 77 #include <stdlib.h> 78 #include <string.h> 79 #include <unistd.h> 80 81 #include "extern.h" 82 83 static void core(int, int, struct kinfo_proc *); 84 static void datadump(int, int, struct kinfo_proc *, u_long, int); 85 static void killed(int); 86 static void restart_target(void); 87 static void usage(void) __dead2; 88 static void userdump(int, struct kinfo_proc *, u_long, int); 89 90 kvm_t *kd; 91 92 static int data_offset; 93 static pid_t pid; 94 95 int 96 main(argc, argv) 97 int argc; 98 char *argv[]; 99 { 100 struct kinfo_proc *ki = NULL; 101 struct exec exec; 102 int ch, cnt, efd, fd, sflag, uid; 103 char *binfile, *corefile; 104 char errbuf[_POSIX2_LINE_MAX], fname[MAXPATHLEN]; 105 int is_aout; 106 107 sflag = 0; 108 corefile = NULL; 109 while ((ch = getopt(argc, argv, "c:s")) != -1) { 110 switch (ch) { 111 case 'c': 112 corefile = optarg; 113 break; 114 case 's': 115 sflag = 1; 116 break; 117 default: 118 usage(); 119 break; 120 } 121 } 122 argv += optind; 123 argc -= optind; 124 125 /* XXX we should check that the pid argument is really a number */ 126 switch (argc) { 127 case 1: 128 pid = atoi(argv[0]); 129 asprintf(&binfile, "/proc/%d/file", pid); 130 if (binfile == NULL) 131 errx(1, "allocation failure"); 132 break; 133 case 2: 134 pid = atoi(argv[1]); 135 binfile = argv[0]; 136 break; 137 default: 138 usage(); 139 } 140 141 efd = open(binfile, O_RDONLY, 0); 142 if (efd < 0) 143 err(1, "%s", binfile); 144 145 cnt = read(efd, &exec, sizeof(exec)); 146 if (cnt != sizeof(exec)) 147 errx(1, "%s exec header: %s", 148 binfile, cnt > 0 ? strerror(EIO) : strerror(errno)); 149 if (!N_BADMAG(exec)) { 150 is_aout = 1; 151 /* 152 * This legacy a.out support uses the kvm interface instead 153 * of procfs. 154 */ 155 kd = kvm_openfiles(0, 0, 0, O_RDONLY, errbuf); 156 if (kd == NULL) 157 errx(1, "%s", errbuf); 158 159 uid = getuid(); 160 161 ki = kvm_getprocs(kd, KERN_PROC_PID, pid, &cnt); 162 if (ki == NULL || cnt != 1) 163 errx(1, "%d: not found", pid); 164 165 if (ki->ki_ruid != uid && uid != 0) 166 errx(1, "%d: not owner", pid); 167 168 if (ki->ki_stat == SZOMB) 169 errx(1, "%d: zombie", pid); 170 171 if (ki->ki_flag & P_WEXIT) 172 errx(1, "%d: process exiting", pid); 173 if (ki->ki_flag & P_SYSTEM) /* Swapper or pagedaemon. */ 174 errx(1, "%d: system process", pid); 175 if (exec.a_text != ptoa(ki->ki_tsize)) 176 errx(1, "The executable %s does not belong to" 177 " process %d!\n" 178 "Text segment size (in bytes): executable %ld," 179 " process %d", binfile, pid, exec.a_text, 180 ptoa(ki->ki_tsize)); 181 data_offset = N_DATOFF(exec); 182 } else if (IS_ELF(*(Elf_Ehdr *)&exec)) { 183 is_aout = 0; 184 close(efd); 185 } else 186 errx(1, "Invalid executable file"); 187 188 if (corefile == NULL) { 189 (void)snprintf(fname, sizeof(fname), "core.%d", pid); 190 corefile = fname; 191 } 192 fd = open(corefile, O_RDWR|O_CREAT|O_TRUNC, DEFFILEMODE); 193 if (fd < 0) 194 err(1, "%s", corefile); 195 196 if (sflag) { 197 signal(SIGHUP, killed); 198 signal(SIGINT, killed); 199 signal(SIGTERM, killed); 200 if (kill(pid, SIGSTOP) == -1) 201 err(1, "%d: stop signal", pid); 202 atexit(restart_target); 203 } 204 205 if (is_aout) 206 core(efd, fd, ki); 207 else 208 elf_coredump(fd, pid); 209 210 (void)close(fd); 211 exit(0); 212 } 213 214 /* 215 * core -- 216 * Build the core file. 217 */ 218 void 219 core(efd, fd, ki) 220 int efd; 221 int fd; 222 struct kinfo_proc *ki; 223 { 224 union { 225 struct user user; 226 struct { 227 char uabytes[ctob(UAREA_PAGES)]; 228 char ksbytes[ctob(KSTACK_PAGES)]; 229 } bytes; 230 } uarea; 231 int tsize = ki->ki_tsize; 232 int dsize = ki->ki_dsize; 233 int ssize = ki->ki_ssize; 234 int cnt; 235 236 /* Read in user struct */ 237 cnt = kvm_read(kd, (u_long)ki->ki_addr, uarea.bytes.uabytes, 238 ctob(UAREA_PAGES)); 239 if (cnt != ctob(UAREA_PAGES)) 240 errx(1, "read upages structure: %s", 241 cnt > 0 ? strerror(EIO) : strerror(errno)); 242 243 cnt = kvm_read(kd, (u_long)ki->ki_kstack, uarea.bytes.ksbytes, 244 ctob(KSTACK_PAGES)); 245 if (cnt != ctob(KSTACK_PAGES)) 246 errx(1, "read kstack structure: %s", 247 cnt > 0 ? strerror(EIO) : strerror(errno)); 248 249 /* 250 * Fill in the eproc vm parameters, since these are garbage unless 251 * the kernel is dumping core or something. 252 */ 253 uarea.user.u_kproc = *ki; 254 255 /* Dump user area */ 256 cnt = write(fd, &uarea, sizeof(uarea)); 257 if (cnt != sizeof(uarea)) 258 errx(1, "write user structure: %s", 259 cnt > 0 ? strerror(EIO) : strerror(errno)); 260 261 /* Dump data segment */ 262 datadump(efd, fd, ki, USRTEXT + ctob(tsize), dsize); 263 264 /* Dump stack segment */ 265 userdump(fd, ki, USRSTACK - ctob(ssize), ssize); 266 267 /* Dump machine dependent portions of the core. */ 268 md_core(kd, fd, ki); 269 } 270 271 void 272 datadump(efd, fd, kp, addr, npage) 273 register int efd; 274 register int fd; 275 struct kinfo_proc *kp; 276 register u_long addr; 277 register int npage; 278 { 279 register int cc, delta; 280 char buffer[PAGE_SIZE]; 281 282 delta = data_offset - addr; 283 while (--npage >= 0) { 284 cc = kvm_uread(kd, kp, addr, buffer, PAGE_SIZE); 285 if (cc != PAGE_SIZE) { 286 /* Try to read the page from the executable. */ 287 if (lseek(efd, (off_t)addr + delta, SEEK_SET) == -1) 288 err(1, "seek executable"); 289 cc = read(efd, buffer, sizeof(buffer)); 290 if (cc != sizeof(buffer)) { 291 if (cc < 0) 292 err(1, "read executable"); 293 else /* Assume untouched bss page. */ 294 bzero(buffer, sizeof(buffer)); 295 } 296 } 297 cc = write(fd, buffer, PAGE_SIZE); 298 if (cc != PAGE_SIZE) 299 errx(1, "write data segment: %s", 300 cc > 0 ? strerror(EIO) : strerror(errno)); 301 addr += PAGE_SIZE; 302 } 303 } 304 305 static void 306 killed(sig) 307 int sig; 308 { 309 restart_target(); 310 signal(sig, SIG_DFL); 311 kill(getpid(), sig); 312 } 313 314 static void 315 restart_target() 316 { 317 kill(pid, SIGCONT); 318 } 319 320 void 321 userdump(fd, kp, addr, npage) 322 register int fd; 323 struct kinfo_proc *kp; 324 register u_long addr; 325 register int npage; 326 { 327 register int cc; 328 char buffer[PAGE_SIZE]; 329 330 while (--npage >= 0) { 331 cc = kvm_uread(kd, kp, addr, buffer, PAGE_SIZE); 332 if (cc != PAGE_SIZE) 333 /* Could be an untouched fill-with-zero page. */ 334 bzero(buffer, PAGE_SIZE); 335 cc = write(fd, buffer, PAGE_SIZE); 336 if (cc != PAGE_SIZE) 337 errx(1, "write stack segment: %s", 338 cc > 0 ? strerror(EIO) : strerror(errno)); 339 addr += PAGE_SIZE; 340 } 341 } 342 343 void 344 usage() 345 { 346 (void)fprintf(stderr, "usage: gcore [-s] [-c core] [executable] pid\n"); 347 exit(1); 348 } 349