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 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)gcore.c 8.2 (Berkeley) 9/23/93"; 43 #endif 44 static const char rcsid[] = 45 "$Id: gcore.c,v 1.8 1998/08/24 16:25:30 wosch Exp $"; 46 #endif /* not lint */ 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 #include <sys/param.h> 60 #include <sys/time.h> 61 #include <sys/stat.h> 62 #include <sys/proc.h> 63 #include <sys/user.h> 64 #include <sys/sysctl.h> 65 66 #include <machine/vmparam.h> 67 68 #include <a.out.h> 69 #include <err.h> 70 #include <fcntl.h> 71 #include <kvm.h> 72 #include <limits.h> 73 #include <signal.h> 74 #include <stdio.h> 75 #include <stdlib.h> 76 #include <string.h> 77 #include <unistd.h> 78 79 #include "extern.h" 80 81 void core __P((int, int, struct kinfo_proc *)); 82 void datadump __P((int, int, struct proc *, u_long, int)); 83 void usage __P((void)); 84 void userdump __P((int, struct proc *, u_long, int)); 85 86 kvm_t *kd; 87 /* XXX undocumented routine, should be in kvm.h? */ 88 ssize_t kvm_uread __P((kvm_t *, const struct proc *, u_long, char *, size_t)); 89 90 91 static int data_offset; 92 93 int 94 main(argc, argv) 95 int argc; 96 char *argv[]; 97 { 98 register struct proc *p; 99 struct kinfo_proc *ki; 100 struct exec exec; 101 int ch, cnt, efd, fd, pid, sflag, uid; 102 char *binfile, *corefile; 103 char errbuf[_POSIX2_LINE_MAX], fname[MAXPATHLEN + 1]; 104 105 sflag = 0; 106 corefile = NULL; 107 while ((ch = getopt(argc, argv, "c:s")) != -1) { 108 switch (ch) { 109 case 'c': 110 corefile = optarg; 111 break; 112 case 's': 113 sflag = 1; 114 break; 115 default: 116 usage(); 117 break; 118 } 119 } 120 argv += optind; 121 argc -= optind; 122 123 /* XXX we should check that the pid argument is really a number */ 124 switch (argc) { 125 case 1: 126 pid = atoi(argv[0]); 127 asprintf(&binfile, "/proc/%d/file", pid); 128 if (binfile == NULL) 129 errx(1, "allocation failure"); 130 break; 131 case 2: 132 pid = atoi(argv[1]); 133 binfile = argv[0]; 134 break; 135 default: 136 usage(); 137 } 138 139 kd = kvm_openfiles(0, 0, 0, O_RDONLY, errbuf); 140 if (kd == NULL) 141 errx(1, "%s", errbuf); 142 143 uid = getuid(); 144 145 ki = kvm_getprocs(kd, KERN_PROC_PID, pid, &cnt); 146 if (ki == NULL || cnt != 1) 147 errx(1, "%d: not found", pid); 148 149 p = &ki->kp_proc; 150 if (ki->kp_eproc.e_pcred.p_ruid != uid && uid != 0) 151 errx(1, "%d: not owner", pid); 152 153 if (p->p_stat == SZOMB) 154 errx(1, "%d: zombie", pid); 155 156 if (p->p_flag & P_WEXIT) 157 errx(1, "%d: process exiting", pid); 158 if (p->p_flag & P_SYSTEM) /* Swapper or pagedaemon. */ 159 errx(1, "%d: system process", pid); 160 161 if (corefile == NULL) { 162 (void)snprintf(fname, sizeof(fname), "core.%d", pid); 163 corefile = fname; 164 } 165 fd = open(corefile, O_RDWR|O_CREAT|O_TRUNC, DEFFILEMODE); 166 if (fd < 0) 167 err(1, "%s", corefile); 168 169 efd = open(binfile, O_RDONLY, 0); 170 if (efd < 0) 171 err(1, "%s", binfile); 172 173 cnt = read(efd, &exec, sizeof(exec)); 174 if (cnt != sizeof(exec)) 175 errx(1, "%s exec header: %s", 176 binfile, cnt > 0 ? strerror(EIO) : strerror(errno)); 177 178 /* check the text segment size of the executable and the process */ 179 if (exec.a_text != ptoa(ki->kp_eproc.e_vm.vm_tsize)) 180 errx(1, 181 "The executable %s does not belong to process %d!\n" 182 "Text segment size (in bytes): executable %d, process %d", 183 binfile, pid, exec.a_text, 184 ptoa(ki->kp_eproc.e_vm.vm_tsize)); 185 186 data_offset = N_DATOFF(exec); 187 188 if (sflag && kill(pid, SIGSTOP) < 0) 189 err(1, "%d: stop signal", pid); 190 191 core(efd, fd, ki); 192 193 if (sflag && kill(pid, SIGCONT) < 0) 194 err(1, "%d: continue signal", pid); 195 (void)close(fd); 196 197 exit(0); 198 } 199 200 /* 201 * core -- 202 * Build the core file. 203 */ 204 void 205 core(efd, fd, ki) 206 int efd; 207 int fd; 208 struct kinfo_proc *ki; 209 { 210 union { 211 struct user user; 212 char ubytes[ctob(UPAGES)]; 213 } uarea; 214 struct proc *p = &ki->kp_proc; 215 int tsize = ki->kp_eproc.e_vm.vm_tsize; 216 int dsize = ki->kp_eproc.e_vm.vm_dsize; 217 int ssize = ki->kp_eproc.e_vm.vm_ssize; 218 int cnt; 219 220 /* Read in user struct */ 221 cnt = kvm_read(kd, (u_long)p->p_addr, &uarea, sizeof(uarea)); 222 if (cnt != sizeof(uarea)) 223 errx(1, "read user structure: %s", 224 cnt > 0 ? strerror(EIO) : strerror(errno)); 225 226 /* 227 * Fill in the eproc vm parameters, since these are garbage unless 228 * the kernel is dumping core or something. 229 */ 230 uarea.user.u_kproc = *ki; 231 232 /* Dump user area */ 233 cnt = write(fd, &uarea, sizeof(uarea)); 234 if (cnt != sizeof(uarea)) 235 errx(1, "write user structure: %s", 236 cnt > 0 ? strerror(EIO) : strerror(errno)); 237 238 /* Dump data segment */ 239 datadump(efd, fd, p, USRTEXT + ctob(tsize), dsize); 240 241 /* Dump stack segment */ 242 userdump(fd, p, USRSTACK - ctob(ssize), ssize); 243 244 /* Dump machine dependent portions of the core. */ 245 md_core(kd, fd, ki); 246 } 247 248 void 249 datadump(efd, fd, p, addr, npage) 250 register int efd; 251 register int fd; 252 struct proc *p; 253 register u_long addr; 254 register int npage; 255 { 256 register int cc, delta; 257 char buffer[PAGE_SIZE]; 258 259 delta = data_offset - addr; 260 while (--npage >= 0) { 261 cc = kvm_uread(kd, p, addr, buffer, PAGE_SIZE); 262 if (cc != PAGE_SIZE) { 263 /* Try to read the page from the executable. */ 264 if (lseek(efd, (off_t)addr + delta, SEEK_SET) == -1) 265 err(1, "seek executable: %s", strerror(errno)); 266 cc = read(efd, buffer, sizeof(buffer)); 267 if (cc != sizeof(buffer)) 268 if (cc < 0) 269 err(1, "read executable"); 270 else /* Assume untouched bss page. */ 271 bzero(buffer, sizeof(buffer)); 272 } 273 cc = write(fd, buffer, PAGE_SIZE); 274 if (cc != PAGE_SIZE) 275 errx(1, "write data segment: %s", 276 cc > 0 ? strerror(EIO) : strerror(errno)); 277 addr += PAGE_SIZE; 278 } 279 } 280 281 void 282 userdump(fd, p, addr, npage) 283 register int fd; 284 struct proc *p; 285 register u_long addr; 286 register int npage; 287 { 288 register int cc; 289 char buffer[PAGE_SIZE]; 290 291 while (--npage >= 0) { 292 cc = kvm_uread(kd, p, addr, buffer, PAGE_SIZE); 293 if (cc != PAGE_SIZE) 294 /* Could be an untouched fill-with-zero page. */ 295 bzero(buffer, PAGE_SIZE); 296 cc = write(fd, buffer, PAGE_SIZE); 297 if (cc != PAGE_SIZE) 298 errx(1, "write stack segment: %s", 299 cc > 0 ? strerror(EIO) : strerror(errno)); 300 addr += PAGE_SIZE; 301 } 302 } 303 304 void 305 usage() 306 { 307 (void)fprintf(stderr, "usage: gcore [-s] [-c core] executable pid\n"); 308 exit(1); 309 } 310