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) 2019, Joyent, Inc.
14 */
15
16 /*
17 * merge CTF containers
18 */
19
20 #include <stdio.h>
21 #include <libctf.h>
22 #include <sys/stat.h>
23 #include <sys/types.h>
24 #include <fcntl.h>
25 #include <errno.h>
26 #include <strings.h>
27 #include <assert.h>
28 #include <unistd.h>
29 #include <sys/fcntl.h>
30 #include <stdlib.h>
31 #include <libelf.h>
32 #include <gelf.h>
33 #include <sys/mman.h>
34 #include <libgen.h>
35 #include <stdarg.h>
36 #include <limits.h>
37
38 static char *g_progname;
39 static char *g_unique;
40 static char *g_outfile;
41 static uint_t g_nctf;
42
43 #define CTFMERGE_OK 0
44 #define CTFMERGE_FATAL 1
45 #define CTFMERGE_USAGE 2
46
47 #define CTFMERGE_DEFAULT_NTHREADS 8
48 #define CTFMERGE_ALTEXEC "CTFMERGE_ALTEXEC"
49
50 static void
51 ctfmerge_fatal(const char *fmt, ...)
52 {
53 va_list ap;
54
55 (void) fprintf(stderr, "%s: ", g_progname);
56 va_start(ap, fmt);
57 (void) vfprintf(stderr, fmt, ap);
58 va_end(ap);
59
60 if (g_outfile != NULL)
61 (void) unlink(g_outfile);
62
63 exit(CTFMERGE_FATAL);
64 }
65
66 /*
67 * We failed to find CTF for this file, check if it's OK. If we're not derived
68 * from C, or we have the -m option, we let missing CTF pass.
69 */
70 static void
71 ctfmerge_check_for_c(const char *name, Elf *elf, uint_t flags)
72 {
73 char errmsg[1024];
74
75 if (flags & CTF_ALLOW_MISSING_DEBUG)
76 return;
77
78 switch (ctf_has_c_source(elf, errmsg, sizeof (errmsg))) {
79 case CHR_ERROR:
80 ctfmerge_fatal("failed to open %s: %s\n", name, errmsg);
81 break;
82
83 case CHR_NO_C_SOURCE:
84 return;
85
86 default:
87 ctfmerge_fatal("failed to open %s: %s\n", name,
88 ctf_errmsg(ECTF_NOCTFDATA));
89 break;
90 }
91 }
92
93 /*
94 * Go through and construct enough information for this Elf Object to try and do
95 * a ctf_bufopen().
96 */
97 static int
98 ctfmerge_elfopen(const char *name, Elf *elf, ctf_merge_t *cmh, uint_t flags)
99 {
100 GElf_Ehdr ehdr;
101 GElf_Shdr shdr;
102 Elf_Scn *scn;
103 Elf_Data *ctf_data, *str_data, *sym_data;
104 ctf_sect_t ctfsect, symsect, strsect;
105 ctf_file_t *fp;
106 int err;
107
108 if (gelf_getehdr(elf, &ehdr) == NULL)
109 ctfmerge_fatal("failed to get ELF header for %s: %s\n",
110 name, elf_errmsg(elf_errno()));
111
112 bzero(&ctfsect, sizeof (ctf_sect_t));
113 bzero(&symsect, sizeof (ctf_sect_t));
114 bzero(&strsect, sizeof (ctf_sect_t));
115
116 scn = NULL;
117 while ((scn = elf_nextscn(elf, scn)) != NULL) {
118 const char *sname;
119
120 if (gelf_getshdr(scn, &shdr) == NULL)
121 ctfmerge_fatal("failed to get section header for "
122 "file %s: %s\n", name, elf_errmsg(elf_errno()));
123
124 sname = elf_strptr(elf, ehdr.e_shstrndx, shdr.sh_name);
125 if (shdr.sh_type == SHT_PROGBITS &&
126 strcmp(sname, ".SUNW_ctf") == 0) {
127 ctfsect.cts_name = sname;
128 ctfsect.cts_type = shdr.sh_type;
129 ctfsect.cts_flags = shdr.sh_flags;
130 ctfsect.cts_size = shdr.sh_size;
131 ctfsect.cts_entsize = shdr.sh_entsize;
132 ctfsect.cts_offset = (off64_t)shdr.sh_offset;
133
134 ctf_data = elf_getdata(scn, NULL);
135 if (ctf_data == NULL)
136 ctfmerge_fatal("failed to get ELF CTF "
137 "data section for %s: %s\n", name,
138 elf_errmsg(elf_errno()));
139 ctfsect.cts_data = ctf_data->d_buf;
140 } else if (shdr.sh_type == SHT_SYMTAB) {
141 Elf_Scn *strscn;
142 GElf_Shdr strhdr;
143
144 symsect.cts_name = sname;
145 symsect.cts_type = shdr.sh_type;
146 symsect.cts_flags = shdr.sh_flags;
147 symsect.cts_size = shdr.sh_size;
148 symsect.cts_entsize = shdr.sh_entsize;
149 symsect.cts_offset = (off64_t)shdr.sh_offset;
150
151 if ((strscn = elf_getscn(elf, shdr.sh_link)) == NULL ||
152 gelf_getshdr(strscn, &strhdr) == NULL)
153 ctfmerge_fatal("failed to get "
154 "string table for file %s: %s\n", name,
155 elf_errmsg(elf_errno()));
156
157 strsect.cts_name = elf_strptr(elf, ehdr.e_shstrndx,
158 strhdr.sh_name);
159 strsect.cts_type = strhdr.sh_type;
160 strsect.cts_flags = strhdr.sh_flags;
161 strsect.cts_size = strhdr.sh_size;
162 strsect.cts_entsize = strhdr.sh_entsize;
163 strsect.cts_offset = (off64_t)strhdr.sh_offset;
164
165 sym_data = elf_getdata(scn, NULL);
166 if (sym_data == NULL)
167 ctfmerge_fatal("failed to get ELF CTF "
168 "data section for %s: %s\n", name,
169 elf_errmsg(elf_errno()));
170 symsect.cts_data = sym_data->d_buf;
171
172 str_data = elf_getdata(strscn, NULL);
173 if (str_data == NULL)
174 ctfmerge_fatal("failed to get ELF CTF "
175 "data section for %s: %s\n", name,
176 elf_errmsg(elf_errno()));
177 strsect.cts_data = str_data->d_buf;
178 }
179 }
180
181 if (ctfsect.cts_type == SHT_NULL) {
182 ctfmerge_check_for_c(name, elf, flags);
183 return (ENOENT);
184 }
185
186 if (symsect.cts_type != SHT_NULL && strsect.cts_type != SHT_NULL) {
187 fp = ctf_bufopen(&ctfsect, &symsect, &strsect, &err);
188 } else {
189 fp = ctf_bufopen(&ctfsect, NULL, NULL, &err);
190 }
191
192 if (fp == NULL) {
193 ctfmerge_fatal("failed to open file %s: %s\n",
194 name, ctf_errmsg(err));
195 }
196
197 if ((err = ctf_merge_add(cmh, fp)) != 0) {
198 ctfmerge_fatal("failed to add input %s: %s\n",
199 name, ctf_errmsg(err));
200 }
201
202 g_nctf++;
203 return (0);
204 }
205
206 static void
207 ctfmerge_read_archive(const char *name, int fd, Elf *elf,
208 ctf_merge_t *cmh, uint_t flags)
209 {
210 Elf_Cmd cmd = ELF_C_READ;
211 int cursec = 1;
212 Elf *aelf;
213
214 while ((aelf = elf_begin(fd, cmd, elf)) != NULL) {
215 char *nname = NULL;
216 Elf_Arhdr *arhdr;
217
218 if ((arhdr = elf_getarhdr(aelf)) == NULL)
219 ctfmerge_fatal("failed to get archive header %d for "
220 "%s: %s\n", cursec, name, elf_errmsg(elf_errno()));
221
222 cmd = elf_next(aelf);
223
224 if (*(arhdr->ar_name) == '/')
225 goto next;
226
227 if (asprintf(&nname, "%s.%s.%d", name, arhdr->ar_name,
228 cursec) < 0)
229 ctfmerge_fatal("failed to allocate memory for archive "
230 "%d of file %s\n", cursec, name);
231
232 switch (elf_kind(aelf)) {
233 case ELF_K_AR:
234 ctfmerge_read_archive(nname, fd, aelf, cmh, flags);
235 break;
236 case ELF_K_ELF:
237 /* ctfmerge_elfopen() takes ownership of aelf. */
238 if (ctfmerge_elfopen(nname, aelf, cmh, flags) == 0)
239 aelf = NULL;
240 break;
241 default:
242 ctfmerge_fatal("unknown elf kind (%d) in archive %d "
243 "for %s\n", elf_kind(aelf), cursec, name);
244 break;
245 }
246
247 next:
248 (void) elf_end(aelf);
249 free(nname);
250 cursec++;
251 }
252 }
253
254 static void
255 ctfmerge_file_add(ctf_merge_t *cmh, const char *file, uint_t flags)
256 {
257 Elf *e;
258 int fd;
259
260 if ((fd = open(file, O_RDONLY)) < 0) {
261 ctfmerge_fatal("failed to open file %s: %s\n",
262 file, strerror(errno));
263 }
264
265 if ((e = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
266 (void) close(fd);
267 ctfmerge_fatal("failed to open %s: %s\n",
268 file, elf_errmsg(elf_errno()));
269 }
270
271 switch (elf_kind(e)) {
272 case ELF_K_AR:
273 ctfmerge_read_archive(file, fd, e, cmh, flags);
274 break;
275
276 case ELF_K_ELF:
277 /* ctfmerge_elfopen() takes ownership of e. */
278 if (ctfmerge_elfopen(file, e, cmh, flags) == 0)
279 e = NULL;
280 break;
281
282 default:
283 ctfmerge_fatal("unknown elf kind (%d) for %s\n",
284 elf_kind(e), file);
285 }
286
287 (void) elf_end(e);
288 (void) close(fd);
289 }
290
291 static void
292 ctfmerge_usage(const char *fmt, ...)
293 {
294 if (fmt != NULL) {
295 va_list ap;
296
297 (void) fprintf(stderr, "%s: ", g_progname);
298 va_start(ap, fmt);
299 (void) vfprintf(stderr, fmt, ap);
300 va_end(ap);
301 }
302
303 (void) fprintf(stderr, "Usage: %s [-m] [-d uniqfile] [-l label] "
304 "[-L labelenv] [-j nthrs] -o outfile file ...\n"
305 "\n"
306 "\t-d uniquify merged output against uniqfile\n"
307 "\t-j use nthrs threads to perform the merge\n"
308 "\t-l set output container's label to specified value\n"
309 "\t-L set output container's label to value from environment\n"
310 "\t-m allow C-based input files to not have CTF\n"
311 "\t-o file to add CTF data to\n",
312 g_progname);
313 }
314
315 static void
316 ctfmerge_altexec(char **argv)
317 {
318 const char *alt;
319 char *altexec;
320
321 alt = getenv(CTFMERGE_ALTEXEC);
322 if (alt == NULL || *alt == '\0')
323 return;
324
325 altexec = strdup(alt);
326 if (altexec == NULL)
327 ctfmerge_fatal("failed to allocate memory for altexec\n");
328 if (unsetenv(CTFMERGE_ALTEXEC) != 0)
329 ctfmerge_fatal("failed to unset %s from environment: %s\n",
330 CTFMERGE_ALTEXEC, strerror(errno));
331
332 (void) execv(altexec, argv);
333 ctfmerge_fatal("failed to execute alternate program %s: %s",
334 altexec, strerror(errno));
335 }
336
337 int
338 main(int argc, char *argv[])
339 {
340 int err, i, c, ofd;
341 uint_t nthreads = CTFMERGE_DEFAULT_NTHREADS;
342 char *tmpfile = NULL, *label = NULL;
343 int wflags = CTF_ELFWRITE_F_COMPRESS;
344 uint_t flags = 0;
345 ctf_merge_t *cmh;
346 ctf_file_t *ofp;
347 long argj;
348 char *eptr;
349
350 g_progname = basename(argv[0]);
351
352 ctfmerge_altexec(argv);
353
354 /*
355 * We support a subset of the old CTF merge flags, mostly for
356 * compatibility.
357 */
358 while ((c = getopt(argc, argv, ":d:fgj:l:L:mo:t")) != -1) {
359 switch (c) {
360 case 'd':
361 g_unique = optarg;
362 break;
363 case 'f':
364 /* Silently ignored for compatibility */
365 break;
366 case 'g':
367 /* Silently ignored for compatibility */
368 break;
369 case 'j':
370 errno = 0;
371 argj = strtol(optarg, &eptr, 10);
372 if (errno != 0 || argj == LONG_MAX ||
373 argj > 1024 || *eptr != '\0') {
374 ctfmerge_fatal("invalid argument for -j: %s\n",
375 optarg);
376 }
377 nthreads = (uint_t)argj;
378 break;
379 case 'l':
380 label = optarg;
381 break;
382 case 'L':
383 label = getenv(optarg);
384 break;
385 case 'm':
386 flags |= CTF_ALLOW_MISSING_DEBUG;
387 break;
388 case 'o':
389 g_outfile = optarg;
390 break;
391 case 't':
392 /* Silently ignored for compatibility */
393 break;
394 case ':':
395 ctfmerge_usage("Option -%c requires an operand\n",
396 optopt);
397 return (CTFMERGE_USAGE);
398 case '?':
399 ctfmerge_usage("Unknown option: -%c\n", optopt);
400 return (CTFMERGE_USAGE);
401 }
402 }
403
404 if (g_outfile == NULL) {
405 ctfmerge_usage("missing required -o output file\n");
406 return (CTFMERGE_USAGE);
407 }
408
409 (void) elf_version(EV_CURRENT);
410
411 /*
412 * Obviously this isn't atomic, but at least gives us a good starting
413 * point.
414 */
415 if ((ofd = open(g_outfile, O_RDWR)) < 0)
416 ctfmerge_fatal("cannot open output file %s: %s\n", g_outfile,
417 strerror(errno));
418
419 argc -= optind;
420 argv += optind;
421
422 if (argc < 1) {
423 ctfmerge_usage("no input files specified");
424 return (CTFMERGE_USAGE);
425 }
426
427 cmh = ctf_merge_init(ofd, &err);
428 if (cmh == NULL)
429 ctfmerge_fatal("failed to create merge handle: %s\n",
430 ctf_errmsg(err));
431
432 if ((err = ctf_merge_set_nthreads(cmh, nthreads)) != 0)
433 ctfmerge_fatal("failed to set parallelism to %u: %s\n",
434 nthreads, ctf_errmsg(err));
435
436 for (i = 0; i < argc; i++) {
437 ctfmerge_file_add(cmh, argv[i], flags);
438 }
439
440 if (g_nctf == 0) {
441 ctf_merge_fini(cmh);
442 return (0);
443 }
444
445 if (g_unique != NULL) {
446 ctf_file_t *ufp;
447 char *base;
448
449 ufp = ctf_open(g_unique, &err);
450 if (ufp == NULL) {
451 ctfmerge_fatal("failed to open uniquify file %s: %s\n",
452 g_unique, ctf_errmsg(err));
453 }
454
455 base = basename(g_unique);
456 (void) ctf_merge_uniquify(cmh, ufp, base);
457 }
458
459 if (label != NULL) {
460 if ((err = ctf_merge_label(cmh, label)) != 0)
461 ctfmerge_fatal("failed to add label %s: %s\n", label,
462 ctf_errmsg(err));
463 }
464
465 err = ctf_merge_merge(cmh, &ofp);
466 if (err != 0)
467 ctfmerge_fatal("failed to merge types: %s\n", ctf_errmsg(err));
468 ctf_merge_fini(cmh);
469
470 if (asprintf(&tmpfile, "%s.ctf", g_outfile) == -1)
471 ctfmerge_fatal("ran out of memory for temporary file name\n");
472 err = ctf_elfwrite(ofp, g_outfile, tmpfile, wflags);
473 if (err == CTF_ERR) {
474 (void) unlink(tmpfile);
475 free(tmpfile);
476 ctfmerge_fatal("encountered a libctf error: %s!\n",
477 ctf_errmsg(ctf_errno(ofp)));
478 }
479
480 if (rename(tmpfile, g_outfile) != 0) {
481 (void) unlink(tmpfile);
482 free(tmpfile);
483 ctfmerge_fatal("failed to rename temporary file: %s\n",
484 strerror(errno));
485 }
486 free(tmpfile);
487
488 return (CTFMERGE_OK);
489 }