1 /* 2 * This file and its contents are supplied under the terms of the 3 * Common Development and Distribution License ("CDDL"), version 1.0. 4 * You may only use this file in accordance with the terms of version 5 * 1.0 of the CDDL. 6 * 7 * A full copy of the text of the CDDL should have accompanied this 8 * source. A copy of the CDDL is also available via the Internet at 9 * http://www.illumos.org/license/CDDL. 10 */ 11 12 /* 13 * Copyright (c) 2015, Joyent, Inc. 14 */ 15 16 /* 17 * Create CTF from extant debugging information 18 */ 19 20 #include <stdio.h> 21 #include <unistd.h> 22 #include <stdlib.h> 23 #include <stdarg.h> 24 #include <sys/types.h> 25 #include <sys/stat.h> 26 #include <fcntl.h> 27 #include <errno.h> 28 #include <libelf.h> 29 #include <libctf.h> 30 #include <string.h> 31 #include <libgen.h> 32 #include <limits.h> 33 #include <strings.h> 34 #include <sys/debug.h> 35 36 #define CTFCONVERT_OK 0 37 #define CTFCONVERT_FATAL 1 38 #define CTFCONVERT_USAGE 2 39 40 #define CTFCONVERT_DEFAULT_NTHREADS 4 41 42 #define CTFCONVERT_ALTEXEC "CTFCONVERT_ALTEXEC" 43 44 static char *ctfconvert_progname; 45 46 static void 47 ctfconvert_fatal(const char *fmt, ...) 48 { 49 va_list ap; 50 51 (void) fprintf(stderr, "%s: ", ctfconvert_progname); 52 va_start(ap, fmt); 53 (void) vfprintf(stderr, fmt, ap); 54 va_end(ap); 55 56 exit(CTFCONVERT_FATAL); 57 } 58 59 60 static void 61 ctfconvert_usage(const char *fmt, ...) 62 { 63 if (fmt != NULL) { 64 va_list ap; 65 66 (void) fprintf(stderr, "%s: ", ctfconvert_progname); 67 va_start(ap, fmt); 68 (void) vfprintf(stderr, fmt, ap); 69 va_end(ap); 70 } 71 72 (void) fprintf(stderr, "Usage: %s [-is] [-j nthrs] [-l label | " 73 "-L labelenv] [-o outfile] input\n" 74 "\n" 75 "\t-i ignore files not built partially from C sources\n" 76 "\t-j use nthrs threads to perform the merge\n" 77 "\t-k keep around original input file on failure\n" 78 "\t-o copy input to outfile and add CTF\n" 79 "\t-l set output container's label to specified value\n" 80 "\t-L set output container's label to value from environment\n", 81 ctfconvert_progname); 82 } 83 84 /* 85 * This is a bit unfortunate. Traditionally we do type uniquification across all 86 * modules in the kernel, including ip and unix against genunix. However, when 87 * _MACHDEP is defined, then the cpu_t ends up having an additional member 88 * (cpu_m), thus changing the ability for us to uniquify against it. This in 89 * turn causes a lot of type sprawl, as there's a lot of things that end up 90 * referring to the cpu_t and it chains out from there. 91 * 92 * So, if we find that a cpu_t has been defined and it has a couple of useful 93 * sentinel members and it does *not* have the cpu_m member, then we will try 94 * and lookup or create a forward declaration to the machcpu, append it to the 95 * end, and update the file. 96 * 97 * This currently is only invoked if an undocumented option -X is passed. This 98 * value is private to illumos and it can be changed at any time inside of it, 99 * so if -X wants to be used for something, it should be. The ability to rely on 100 * -X for others is strictly not an interface in any way, shape, or form. 101 * 102 * The following struct contains most of the information that we care about and 103 * that we want to validate exists before we decide what to do. 104 */ 105 106 typedef struct ctfconvert_fixup { 107 boolean_t cf_cyclic; /* Do we have a cpu_cyclic member */ 108 boolean_t cf_mcpu; /* We have a cpu_m member */ 109 boolean_t cf_lastpad; /* Is the pad member the last entry */ 110 ulong_t cf_padoff; /* offset of the pad */ 111 } ctfconvert_fixup_t; 112 113 /* ARGSUSED */ 114 static int 115 ctfconvert_fixup_genunix_cb(const char *name, ctf_id_t tid, ulong_t off, 116 void *arg) 117 { 118 ctfconvert_fixup_t *cfp = arg; 119 120 cfp->cf_lastpad = B_FALSE; 121 if (strcmp(name, "cpu_cyclic") == 0) { 122 cfp->cf_cyclic = B_TRUE; 123 return (0); 124 } 125 126 if (strcmp(name, "cpu_m") == 0) { 127 cfp->cf_mcpu = B_TRUE; 128 return (0); 129 } 130 131 if (strcmp(name, "cpu_m_pad") == 0) { 132 cfp->cf_lastpad = B_TRUE; 133 cfp->cf_padoff = off; 134 return (0); 135 } 136 137 return (0); 138 } 139 140 static void 141 ctfconvert_fixup_genunix(ctf_file_t *fp) 142 { 143 ctf_id_t cpuid, mcpu; 144 ssize_t sz; 145 ctfconvert_fixup_t cf; 146 int model, ptrsz; 147 148 cpuid = ctf_lookup_by_name(fp, "struct cpu"); 149 if (cpuid == CTF_ERR) 150 return; 151 152 if (ctf_type_kind(fp, cpuid) != CTF_K_STRUCT) 153 return; 154 155 if ((sz = ctf_type_size(fp, cpuid)) == CTF_ERR) 156 return; 157 158 model = ctf_getmodel(fp); 159 VERIFY(model == CTF_MODEL_ILP32 || model == CTF_MODEL_LP64); 160 ptrsz = model == CTF_MODEL_ILP32 ? 4 : 8; 161 162 bzero(&cf, sizeof (ctfconvert_fixup_t)); 163 if (ctf_member_iter(fp, cpuid, ctfconvert_fixup_genunix_cb, &cf) == 164 CTF_ERR) 165 return; 166 167 /* 168 * Finally, we want to verify that the cpu_m is actually the last member 169 * that we have here. 170 */ 171 if (cf.cf_cyclic == B_FALSE || cf.cf_mcpu == B_TRUE || 172 cf.cf_lastpad == B_FALSE) { 173 return; 174 } 175 176 if (cf.cf_padoff + ptrsz * NBBY != sz * NBBY) { 177 return; 178 } 179 180 /* 181 * Okay, we're going to do this, try to find a struct machcpu. We either 182 * want a forward or a struct. If we find something else, error. If we 183 * find nothing, add a forward and then add the member. 184 */ 185 mcpu = ctf_lookup_by_name(fp, "struct machcpu"); 186 if (mcpu == CTF_ERR) { 187 mcpu = ctf_add_forward(fp, CTF_ADD_NONROOT, "machcpu", 188 CTF_K_STRUCT); 189 if (mcpu == CTF_ERR) { 190 ctfconvert_fatal("failed to add 'struct machcpu' " 191 "forward: %s", ctf_errmsg(ctf_errno(fp))); 192 } 193 } else { 194 int kind; 195 if ((kind = ctf_type_kind(fp, mcpu)) == CTF_ERR) { 196 ctfconvert_fatal("failed to get the type kind for " 197 "the struct machcpu: %s", 198 ctf_errmsg(ctf_errno(fp))); 199 } 200 201 if (kind != CTF_K_STRUCT && kind != CTF_K_FORWARD) 202 ctfconvert_fatal("encountered a struct machcpu of the " 203 "wrong type, found type kind %d\n", kind); 204 } 205 206 if (ctf_update(fp) == CTF_ERR) { 207 ctfconvert_fatal("failed to update output file: %s\n", 208 ctf_errmsg(ctf_errno(fp))); 209 } 210 211 if (ctf_add_member(fp, cpuid, "cpu_m", mcpu, sz * NBBY) == CTF_ERR) { 212 ctfconvert_fatal("failed to add the m_cpu member: %s\n", 213 ctf_errmsg(ctf_errno(fp))); 214 } 215 216 if (ctf_update(fp) == CTF_ERR) { 217 ctfconvert_fatal("failed to update output file: %s\n", 218 ctf_errmsg(ctf_errno(fp))); 219 } 220 221 VERIFY(ctf_type_size(fp, cpuid) == sz); 222 } 223 224 static void 225 ctfconvert_altexec(char **argv) 226 { 227 const char *alt; 228 char *altexec; 229 230 alt = getenv(CTFCONVERT_ALTEXEC); 231 if (alt == NULL || *alt == '\0') 232 return; 233 234 altexec = strdup(alt); 235 if (altexec == NULL) 236 ctfconvert_fatal("failed to allocate memory for altexec\n"); 237 if (unsetenv(CTFCONVERT_ALTEXEC) != 0) 238 ctfconvert_fatal("failed to unset %s from environment: %s\n", 239 CTFCONVERT_ALTEXEC, strerror(errno)); 240 241 (void) execv(altexec, argv); 242 ctfconvert_fatal("failed to execute alternate program %s: %s", 243 altexec, strerror(errno)); 244 } 245 246 int 247 main(int argc, char *argv[]) 248 { 249 int c, ifd, err; 250 boolean_t keep = B_FALSE; 251 uint_t flags = 0; 252 uint_t nthreads = CTFCONVERT_DEFAULT_NTHREADS; 253 const char *outfile = NULL; 254 const char *label = NULL; 255 const char *infile = NULL; 256 char *tmpfile; 257 ctf_file_t *ofp; 258 long argj; 259 char *eptr; 260 char buf[4096]; 261 boolean_t optx = B_FALSE; 262 263 ctfconvert_progname = basename(argv[0]); 264 265 ctfconvert_altexec(argv); 266 267 while ((c = getopt(argc, argv, ":j:kl:L:o:iX")) != -1) { 268 switch (c) { 269 case 'k': 270 keep = B_TRUE; 271 break; 272 case 'l': 273 label = optarg; 274 break; 275 case 'L': 276 label = getenv(optarg); 277 break; 278 case 'j': 279 errno = 0; 280 argj = strtol(optarg, &eptr, 10); 281 if (errno != 0 || argj == LONG_MAX || 282 argj > 1024 || *eptr != '\0') { 283 ctfconvert_fatal("invalid argument for -j: " 284 "%s\n", optarg); 285 } 286 nthreads = (uint_t)argj; 287 break; 288 case 'o': 289 outfile = optarg; 290 break; 291 case 'i': 292 flags |= CTF_CONVERT_F_IGNNONC; 293 break; 294 case 'X': 295 optx = B_TRUE; 296 break; 297 case ':': 298 ctfconvert_usage("Option -%c requires an operand\n", 299 optopt); 300 return (CTFCONVERT_USAGE); 301 case '?': 302 ctfconvert_usage("Unknown option: -%c\n", optopt); 303 return (CTFCONVERT_USAGE); 304 } 305 } 306 307 argv += optind; 308 argc -= optind; 309 310 if (argc < 1) { 311 ctfconvert_usage("Missing required input file\n"); 312 return (CTFCONVERT_USAGE); 313 } 314 infile = argv[0]; 315 316 if (elf_version(EV_CURRENT) == EV_NONE) 317 ctfconvert_fatal("failed to initialize libelf: library is " 318 "out of date\n"); 319 320 ifd = open(infile, O_RDONLY); 321 if (ifd < 0) { 322 ctfconvert_fatal("failed to open input file %s: %s\n", infile, 323 strerror(errno)); 324 } 325 326 /* 327 * By default we remove the input file on failure unless we've been 328 * given an output file or -k has been specified. 329 */ 330 if (outfile != NULL && strcmp(infile, outfile) != 0) 331 keep = B_TRUE; 332 333 ofp = ctf_fdconvert(ifd, label, nthreads, flags, &err, buf, 334 sizeof (buf)); 335 if (ofp == NULL) { 336 /* 337 * -i says that we shouldn't concern ourselves with source files 338 * that weren't built from C source code in part. Because this 339 * has been traditionally used across all of illumos, we still 340 * honor it. 341 */ 342 if ((flags & CTF_CONVERT_F_IGNNONC) != 0 && 343 err == ECTF_CONVNOCSRC) { 344 exit(CTFCONVERT_OK); 345 } 346 if (keep == B_FALSE) 347 (void) unlink(infile); 348 ctfconvert_fatal("CTF conversion failed: %s\n", 349 err == ECTF_CONVBKERR ? buf : ctf_errmsg(err)); 350 } 351 352 if (optx == B_TRUE) 353 ctfconvert_fixup_genunix(ofp); 354 355 tmpfile = NULL; 356 if (outfile == NULL || strcmp(infile, outfile) == 0) { 357 if (asprintf(&tmpfile, "%s.ctf", infile) == -1) { 358 if (keep == B_FALSE) 359 (void) unlink(infile); 360 ctfconvert_fatal("failed to allocate memory for " 361 "temporary file: %s\n", strerror(errno)); 362 } 363 outfile = tmpfile; 364 } 365 err = ctf_elfwrite(ofp, infile, outfile, CTF_ELFWRITE_F_COMPRESS); 366 if (err == CTF_ERR) { 367 (void) unlink(outfile); 368 if (keep == B_FALSE) 369 (void) unlink(infile); 370 ctfconvert_fatal("failed to write CTF section to output file: " 371 "%s", ctf_errmsg(ctf_errno(ofp))); 372 } 373 ctf_close(ofp); 374 375 if (tmpfile != NULL) { 376 if (rename(tmpfile, infile) != 0) { 377 int e = errno; 378 (void) unlink(outfile); 379 if (keep == B_FALSE) 380 (void) unlink(infile); 381 ctfconvert_fatal("failed to rename temporary file: " 382 "%s\n", strerror(e)); 383 } 384 } 385 free(tmpfile); 386 387 return (CTFCONVERT_OK); 388 }