1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002 Jake Burkholder 5 * Copyright (c) 2004 Robert Watson 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/types.h> 34 #include <sys/capsicum.h> 35 #include <sys/ktr.h> 36 #include <sys/mman.h> 37 #include <sys/stat.h> 38 39 #include <capsicum_helpers.h> 40 #include <err.h> 41 #include <errno.h> 42 #include <fcntl.h> 43 #include <kvm.h> 44 #include <limits.h> 45 #include <nlist.h> 46 #include <stdint.h> 47 #include <stdio.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <unistd.h> 51 52 #define SBUFLEN 128 53 #define USAGE \ 54 "usage: ktrdump [-cflqrtH] [-i ktrfile] [-M core] [-N system] [-o outfile]\n" 55 56 static void usage(void); 57 58 static struct nlist nl[] = { 59 { .n_name = "_ktr_version" }, 60 { .n_name = "_ktr_entries" }, 61 { .n_name = "_ktr_idx" }, 62 { .n_name = "_ktr_buf" }, 63 { .n_name = NULL } 64 }; 65 66 static int cflag; 67 static int fflag; 68 static int lflag; 69 static int Mflag; 70 static int Nflag; 71 static int qflag; 72 static int rflag; 73 static int tflag; 74 static int iflag; 75 static int hflag; 76 77 static char corefile[PATH_MAX]; 78 static char execfile[PATH_MAX]; 79 static char outfile[PATH_MAX] = "stdout"; 80 81 static char desc[SBUFLEN]; 82 static char errbuf[_POSIX2_LINE_MAX]; 83 static char fbuf[PATH_MAX]; 84 static char obuf[PATH_MAX]; 85 static char sbuf[KTR_PARMS][SBUFLEN]; 86 87 /* 88 * Reads the ktr trace buffer from kernel memory and prints the trace entries. 89 */ 90 int 91 main(int ac, char **av) 92 { 93 u_long parms[KTR_PARMS]; 94 struct ktr_entry *buf; 95 uintmax_t tlast, tnow; 96 unsigned long bufptr; 97 cap_rights_t rights; 98 struct stat sb; 99 kvm_t *kd; 100 FILE *out; 101 char *p; 102 int version; 103 int entries; 104 int count; 105 int index, index2; 106 int parm; 107 int in; 108 int c; 109 int i = 0; 110 111 /* 112 * Parse commandline arguments. 113 */ 114 out = stdout; 115 while ((c = getopt(ac, av, "cflqrtHe:i:m:M:N:o:")) != -1) 116 switch (c) { 117 case 'c': 118 cflag = 1; 119 break; 120 case 'N': 121 case 'e': 122 if (strlcpy(execfile, optarg, sizeof(execfile)) 123 >= sizeof(execfile)) 124 errx(1, "%s: File name too long", optarg); 125 Nflag = 1; 126 break; 127 case 'f': 128 fflag = 1; 129 break; 130 case 'i': 131 iflag = 1; 132 if ((in = open(optarg, O_RDONLY)) == -1) 133 err(1, "%s", optarg); 134 cap_rights_init(&rights, CAP_FSTAT, CAP_MMAP_R); 135 if (caph_rights_limit(in, &rights) < 0) 136 err(1, "unable to limit rights for %s", 137 optarg); 138 break; 139 case 'l': 140 lflag = 1; 141 break; 142 case 'M': 143 case 'm': 144 if (strlcpy(corefile, optarg, sizeof(corefile)) 145 >= sizeof(corefile)) 146 errx(1, "%s: File name too long", optarg); 147 Mflag = 1; 148 break; 149 case 'o': 150 if ((out = fopen(optarg, "w")) == NULL) 151 err(1, "%s", optarg); 152 strlcpy(outfile, optarg, sizeof(outfile)); 153 break; 154 case 'q': 155 qflag++; 156 break; 157 case 'r': 158 rflag = 1; 159 break; 160 case 't': 161 tflag = 1; 162 break; 163 case 'H': 164 hflag = 1; 165 break; 166 case '?': 167 default: 168 usage(); 169 } 170 ac -= optind; 171 av += optind; 172 if (ac != 0) 173 usage(); 174 175 if (caph_limit_stream(fileno(out), CAPH_WRITE) < 0) 176 err(1, "unable to limit rights for %s", outfile); 177 if (caph_limit_stderr() < 0) 178 err(1, "unable to limit rights for stderr"); 179 180 /* 181 * Open our execfile and corefile, resolve needed symbols and read in 182 * the trace buffer. 183 */ 184 if ((kd = kvm_openfiles(Nflag ? execfile : NULL, 185 Mflag ? corefile : NULL, NULL, O_RDONLY, errbuf)) == NULL) 186 errx(1, "%s", errbuf); 187 188 /* 189 * Cache NLS data, for strerror, for err(3), before entering capability 190 * mode. 191 */ 192 caph_cache_catpages(); 193 194 count = kvm_nlist(kd, nl); 195 if (count == -1) 196 errx(1, "%s", kvm_geterr(kd)); 197 if (count > 0) 198 errx(1, "failed to resolve ktr symbols"); 199 if (kvm_read(kd, nl[0].n_value, &version, sizeof(version)) == -1) 200 errx(1, "%s", kvm_geterr(kd)); 201 if (version != KTR_VERSION) 202 errx(1, "ktr version mismatch"); 203 204 /* 205 * Enter Capsicum sandbox. 206 * 207 * kvm_nlist() above uses kldsym(2) for native kernels, and that isn't 208 * allowed in the sandbox. 209 */ 210 if (caph_enter() < 0) 211 err(1, "unable to enter capability mode"); 212 213 if (iflag) { 214 if (fstat(in, &sb) == -1) 215 errx(1, "stat"); 216 entries = sb.st_size / sizeof(*buf); 217 index = 0; 218 buf = mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED, in, 0); 219 if (buf == MAP_FAILED) 220 errx(1, "mmap"); 221 } else { 222 if (kvm_read(kd, nl[1].n_value, &entries, sizeof(entries)) 223 == -1) 224 errx(1, "%s", kvm_geterr(kd)); 225 if ((buf = malloc(sizeof(*buf) * entries)) == NULL) 226 err(1, NULL); 227 if (kvm_read(kd, nl[2].n_value, &index, sizeof(index)) == -1 || 228 kvm_read(kd, nl[3].n_value, &bufptr, 229 sizeof(bufptr)) == -1 || 230 kvm_read(kd, bufptr, buf, sizeof(*buf) * entries) == -1 || 231 kvm_read(kd, nl[2].n_value, &index2, sizeof(index2)) == -1) 232 errx(1, "%s", kvm_geterr(kd)); 233 } 234 235 /* 236 * Print a nice header. 237 */ 238 if (!qflag) { 239 fprintf(out, "%-6s ", "index"); 240 if (cflag) 241 fprintf(out, "%-3s ", "cpu"); 242 if (tflag) 243 fprintf(out, "%-16s ", "timestamp"); 244 if (fflag) 245 fprintf(out, "%-40s ", "file and line"); 246 if (hflag) 247 fprintf(out, "%-18s ", "tid"); 248 fprintf(out, "%s", "trace"); 249 fprintf(out, "\n"); 250 251 fprintf(out, "------ "); 252 if (cflag) 253 fprintf(out, "--- "); 254 if (tflag) 255 fprintf(out, "---------------- "); 256 if (fflag) 257 fprintf(out, 258 "---------------------------------------- "); 259 if (hflag) 260 fprintf(out, "------------------ "); 261 fprintf(out, "----- "); 262 fprintf(out, "\n"); 263 } 264 265 tlast = UINTPTR_MAX; 266 /* 267 * Now tear through the trace buffer. 268 * 269 * In "live" mode, find the oldest entry (first non-NULL entry 270 * after index2) and walk forward. Otherwise, start with the 271 * most recent entry and walk backwards. 272 */ 273 if (!iflag) { 274 if (lflag) { 275 i = index2 + 1 % entries; 276 while (buf[i].ktr_desc == NULL && i != index) { 277 i++; 278 if (i == entries) 279 i = 0; 280 } 281 } else { 282 i = index - 1; 283 if (i < 0) 284 i = entries - 1; 285 } 286 } 287 dump_entries: 288 for (;;) { 289 if (buf[i].ktr_desc == NULL) 290 break; 291 if (kvm_read(kd, (u_long)buf[i].ktr_desc, desc, 292 sizeof(desc)) == -1) 293 errx(1, "%s", kvm_geterr(kd)); 294 desc[sizeof(desc) - 1] = '\0'; 295 parm = 0; 296 for (p = desc; (c = *p++) != '\0';) { 297 if (c != '%') 298 continue; 299 next: if ((c = *p++) == '\0') 300 break; 301 if (parm == KTR_PARMS) 302 errx(1, "too many parameters in \"%s\"", desc); 303 switch (c) { 304 case '0': case '1': case '2': case '3': case '4': 305 case '5': case '6': case '7': case '8': case '9': 306 case '#': case '-': case ' ': case '+': case '\'': 307 case 'h': case 'l': case 'j': case 't': case 'z': 308 case 'q': case 'L': case '.': 309 goto next; 310 case 's': 311 if (kvm_read(kd, (u_long)buf[i].ktr_parms[parm], 312 sbuf[parm], sizeof(sbuf[parm])) == -1) 313 strcpy(sbuf[parm], "(null)"); 314 sbuf[parm][sizeof(sbuf[0]) - 1] = '\0'; 315 parms[parm] = (u_long)sbuf[parm]; 316 parm++; 317 break; 318 default: 319 parms[parm] = buf[i].ktr_parms[parm]; 320 parm++; 321 break; 322 } 323 } 324 fprintf(out, "%6d ", i); 325 if (cflag) 326 fprintf(out, "%3d ", buf[i].ktr_cpu); 327 if (tflag) { 328 tnow = (uintmax_t)buf[i].ktr_timestamp; 329 if (rflag) { 330 if (tlast == UINTPTR_MAX) 331 tlast = tnow; 332 fprintf(out, "%16ju ", !iflag ? tlast - tnow : 333 tnow - tlast); 334 tlast = tnow; 335 } else 336 fprintf(out, "%16ju ", tnow); 337 } 338 if (fflag) { 339 if (kvm_read(kd, (u_long)buf[i].ktr_file, fbuf, 340 sizeof(fbuf)) == -1) 341 strcpy(fbuf, "(null)"); 342 snprintf(obuf, sizeof(obuf), "%s:%d", fbuf, 343 buf[i].ktr_line); 344 fprintf(out, "%-40s ", obuf); 345 } 346 if (hflag) 347 fprintf(out, "%p ", buf[i].ktr_thread); 348 fprintf(out, desc, parms[0], parms[1], parms[2], parms[3], 349 parms[4], parms[5]); 350 fprintf(out, "\n"); 351 if (!iflag) { 352 /* 353 * 'index' and 'index2' are the values of 'ktr_idx' 354 * before and after the KTR buffer was copied into 355 * 'buf'. Since the KTR entries between 'index' and 356 * 'index2' were in flux while the KTR buffer was 357 * being copied to userspace we don't dump them. 358 */ 359 if (lflag) { 360 if (++i == entries) 361 i = 0; 362 if (i == index) 363 break; 364 } else { 365 if (i == index2) 366 break; 367 if (--i < 0) 368 i = entries - 1; 369 } 370 } else { 371 if (++i == entries) 372 break; 373 } 374 } 375 376 /* 377 * In "live" mode, poll 'ktr_idx' periodically and dump any 378 * new entries since our last pass through the ring. 379 */ 380 if (lflag && !iflag) { 381 while (index == index2) { 382 usleep(50 * 1000); 383 if (kvm_read(kd, nl[2].n_value, &index2, 384 sizeof(index2)) == -1) 385 errx(1, "%s", kvm_geterr(kd)); 386 } 387 i = index; 388 index = index2; 389 if (kvm_read(kd, bufptr, buf, sizeof(*buf) * entries) == -1 || 390 kvm_read(kd, nl[2].n_value, &index2, sizeof(index2)) == -1) 391 errx(1, "%s", kvm_geterr(kd)); 392 goto dump_entries; 393 } 394 395 return (0); 396 } 397 398 static void 399 usage(void) 400 { 401 402 fprintf(stderr, USAGE); 403 exit(1); 404 } 405