1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26 /*
27 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
28 */
29
30 #include <assert.h>
31 #include <strings.h>
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <errno.h>
35 #include <ctype.h>
36 #include <alloca.h>
37 #include <libgen.h>
38 #include <stddef.h>
39 #include <sys/sysmacros.h>
40
41 #include <dt_impl.h>
42 #include <dt_program.h>
43 #include <dt_pid.h>
44 #include <dt_string.h>
45 #include <dt_module.h>
46
47 typedef struct dt_pid_probe {
48 dtrace_hdl_t *dpp_dtp;
49 dt_pcb_t *dpp_pcb;
50 dt_proc_t *dpp_dpr;
51 struct ps_prochandle *dpp_pr;
52 const char *dpp_mod;
53 char *dpp_func;
54 const char *dpp_name;
55 const char *dpp_obj;
56 uintptr_t dpp_pc;
57 size_t dpp_size;
58 Lmid_t dpp_lmid;
59 uint_t dpp_nmatches;
60 uint64_t dpp_stret[4];
61 GElf_Sym dpp_last;
62 uint_t dpp_last_taken;
63 } dt_pid_probe_t;
64
65 /*
66 * Compose the lmid and object name into the canonical representation. We
67 * omit the lmid for the default link map for convenience.
68 */
69 static void
dt_pid_objname(char * buf,size_t len,Lmid_t lmid,const char * obj)70 dt_pid_objname(char *buf, size_t len, Lmid_t lmid, const char *obj)
71 {
72 if (lmid == LM_ID_BASE)
73 (void) strncpy(buf, obj, len);
74 else
75 (void) snprintf(buf, len, "LM%lx`%s", lmid, obj);
76 }
77
78 static int
dt_pid_error(dtrace_hdl_t * dtp,dt_pcb_t * pcb,dt_proc_t * dpr,fasttrap_probe_spec_t * ftp,dt_errtag_t tag,const char * fmt,...)79 dt_pid_error(dtrace_hdl_t *dtp, dt_pcb_t *pcb, dt_proc_t *dpr,
80 fasttrap_probe_spec_t *ftp, dt_errtag_t tag, const char *fmt, ...)
81 {
82 va_list ap;
83 int len;
84
85 if (ftp != NULL)
86 dt_free(dtp, ftp);
87
88 va_start(ap, fmt);
89 if (pcb == NULL) {
90 assert(dpr != NULL);
91 len = vsnprintf(dpr->dpr_errmsg, sizeof (dpr->dpr_errmsg),
92 fmt, ap);
93 assert(len >= 2);
94 if (dpr->dpr_errmsg[len - 2] == '\n')
95 dpr->dpr_errmsg[len - 2] = '\0';
96 } else {
97 dt_set_errmsg(dtp, dt_errtag(tag), pcb->pcb_region,
98 pcb->pcb_filetag, pcb->pcb_fileptr ? yylineno : 0, fmt, ap);
99 }
100 va_end(ap);
101
102 return (1);
103 }
104
105 static int
dt_pid_per_sym(dt_pid_probe_t * pp,const GElf_Sym * symp,const char * func)106 dt_pid_per_sym(dt_pid_probe_t *pp, const GElf_Sym *symp, const char *func)
107 {
108 dtrace_hdl_t *dtp = pp->dpp_dtp;
109 dt_pcb_t *pcb = pp->dpp_pcb;
110 dt_proc_t *dpr = pp->dpp_dpr;
111 fasttrap_probe_spec_t *ftp;
112 uint64_t off;
113 char *end;
114 uint_t nmatches = 0;
115 ulong_t sz;
116 int glob, err;
117 int isdash = strcmp("-", func) == 0;
118 pid_t pid;
119
120 pid = Pstatus(pp->dpp_pr)->pr_pid;
121
122 dt_dprintf("creating probe pid%d:%s:%s:%s\n", (int)pid, pp->dpp_obj,
123 func, pp->dpp_name);
124
125 sz = sizeof (fasttrap_probe_spec_t) + (isdash ? 4 :
126 (symp->st_size - 1) * sizeof (ftp->ftps_offs[0]));
127
128 if ((ftp = dt_alloc(dtp, sz)) == NULL) {
129 dt_dprintf("proc_per_sym: dt_alloc(%lu) failed\n", sz);
130 return (1); /* errno is set for us */
131 }
132
133 ftp->ftps_pid = pid;
134 (void) strncpy(ftp->ftps_func, func, sizeof (ftp->ftps_func));
135
136 dt_pid_objname(ftp->ftps_mod, sizeof (ftp->ftps_mod), pp->dpp_lmid,
137 pp->dpp_obj);
138
139 if (!isdash && gmatch("return", pp->dpp_name)) {
140 if (dt_pid_create_return_probe(pp->dpp_pr, dtp, ftp, symp,
141 pp->dpp_stret) < 0) {
142 return (dt_pid_error(dtp, pcb, dpr, ftp,
143 D_PROC_CREATEFAIL, "failed to create return probe "
144 "for '%s': %s", func,
145 dtrace_errmsg(dtp, dtrace_errno(dtp))));
146 }
147
148 nmatches++;
149 }
150
151 if (!isdash && gmatch("entry", pp->dpp_name)) {
152 if (dt_pid_create_entry_probe(pp->dpp_pr, dtp, ftp, symp) < 0) {
153 return (dt_pid_error(dtp, pcb, dpr, ftp,
154 D_PROC_CREATEFAIL, "failed to create entry probe "
155 "for '%s': %s", func,
156 dtrace_errmsg(dtp, dtrace_errno(dtp))));
157 }
158
159 nmatches++;
160 }
161
162 glob = strisglob(pp->dpp_name);
163 if (!glob && nmatches == 0) {
164 off = strtoull(pp->dpp_name, &end, 16);
165 if (*end != '\0') {
166 return (dt_pid_error(dtp, pcb, dpr, ftp, D_PROC_NAME,
167 "'%s' is an invalid probe name", pp->dpp_name));
168 }
169
170 if (off >= symp->st_size) {
171 return (dt_pid_error(dtp, pcb, dpr, ftp, D_PROC_OFF,
172 "offset 0x%llx outside of function '%s'",
173 (u_longlong_t)off, func));
174 }
175
176 err = dt_pid_create_offset_probe(pp->dpp_pr, pp->dpp_dtp, ftp,
177 symp, off);
178
179 if (err == DT_PROC_ERR) {
180 return (dt_pid_error(dtp, pcb, dpr, ftp,
181 D_PROC_CREATEFAIL, "failed to create probe at "
182 "'%s+0x%llx': %s", func, (u_longlong_t)off,
183 dtrace_errmsg(dtp, dtrace_errno(dtp))));
184 }
185
186 if (err == DT_PROC_ALIGN) {
187 return (dt_pid_error(dtp, pcb, dpr, ftp, D_PROC_ALIGN,
188 "offset 0x%llx is not aligned on an instruction",
189 (u_longlong_t)off));
190 }
191
192 nmatches++;
193
194 } else if (glob && !isdash) {
195 if (dt_pid_create_glob_offset_probes(pp->dpp_pr,
196 pp->dpp_dtp, ftp, symp, pp->dpp_name) < 0) {
197 return (dt_pid_error(dtp, pcb, dpr, ftp,
198 D_PROC_CREATEFAIL,
199 "failed to create offset probes in '%s': %s", func,
200 dtrace_errmsg(dtp, dtrace_errno(dtp))));
201 }
202
203 nmatches++;
204 }
205
206 pp->dpp_nmatches += nmatches;
207
208 dt_free(dtp, ftp);
209
210 return (0);
211 }
212
213 static int
dt_pid_sym_filt(void * arg,const GElf_Sym * symp,const char * func)214 dt_pid_sym_filt(void *arg, const GElf_Sym *symp, const char *func)
215 {
216 dt_pid_probe_t *pp = arg;
217
218 if (symp->st_shndx == SHN_UNDEF)
219 return (0);
220
221 if (symp->st_size == 0) {
222 dt_dprintf("st_size of %s is zero\n", func);
223 return (0);
224 }
225
226 if (pp->dpp_last_taken == 0 ||
227 symp->st_value != pp->dpp_last.st_value ||
228 symp->st_size != pp->dpp_last.st_size) {
229 /*
230 * Due to 4524008, _init and _fini may have a bloated st_size.
231 * While this bug has been fixed for a while, old binaries
232 * may exist that still exhibit this problem. As a result, we
233 * don't match _init and _fini though we allow users to
234 * specify them explicitly.
235 */
236 if (strcmp(func, "_init") == 0 || strcmp(func, "_fini") == 0)
237 return (0);
238
239 if ((pp->dpp_last_taken = gmatch(func, pp->dpp_func)) != 0) {
240 pp->dpp_last = *symp;
241 return (dt_pid_per_sym(pp, symp, func));
242 }
243 }
244
245 return (0);
246 }
247
248 static int
dt_pid_per_mod(void * arg,const prmap_t * pmp,const char * obj)249 dt_pid_per_mod(void *arg, const prmap_t *pmp, const char *obj)
250 {
251 dt_pid_probe_t *pp = arg;
252 dtrace_hdl_t *dtp = pp->dpp_dtp;
253 dt_pcb_t *pcb = pp->dpp_pcb;
254 dt_proc_t *dpr = pp->dpp_dpr;
255 GElf_Sym sym;
256
257 if (obj == NULL)
258 return (0);
259
260 (void) Plmid(pp->dpp_pr, pmp->pr_vaddr, &pp->dpp_lmid);
261
262 if ((pp->dpp_obj = strrchr(obj, '/')) == NULL)
263 pp->dpp_obj = obj;
264 else
265 pp->dpp_obj++;
266
267 if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret1", &sym,
268 NULL) == 0)
269 pp->dpp_stret[0] = sym.st_value;
270 else
271 pp->dpp_stret[0] = 0;
272
273 if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret2", &sym,
274 NULL) == 0)
275 pp->dpp_stret[1] = sym.st_value;
276 else
277 pp->dpp_stret[1] = 0;
278
279 if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret4", &sym,
280 NULL) == 0)
281 pp->dpp_stret[2] = sym.st_value;
282 else
283 pp->dpp_stret[2] = 0;
284
285 if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj, ".stret8", &sym,
286 NULL) == 0)
287 pp->dpp_stret[3] = sym.st_value;
288 else
289 pp->dpp_stret[3] = 0;
290
291 dt_dprintf("%s stret %llx %llx %llx %llx\n", obj,
292 (u_longlong_t)pp->dpp_stret[0], (u_longlong_t)pp->dpp_stret[1],
293 (u_longlong_t)pp->dpp_stret[2], (u_longlong_t)pp->dpp_stret[3]);
294
295 /*
296 * If pp->dpp_func contains any globbing meta-characters, we need
297 * to iterate over the symbol table and compare each function name
298 * against the pattern.
299 */
300 if (!strisglob(pp->dpp_func)) {
301 /*
302 * If we fail to lookup the symbol, try interpreting the
303 * function as the special "-" function that indicates that the
304 * probe name should be interpreted as a absolute virtual
305 * address. If that fails and we were matching a specific
306 * function in a specific module, report the error, otherwise
307 * just fail silently in the hopes that some other object will
308 * contain the desired symbol.
309 */
310 if (Pxlookup_by_name(pp->dpp_pr, pp->dpp_lmid, obj,
311 pp->dpp_func, &sym, NULL) != 0) {
312 if (strcmp("-", pp->dpp_func) == 0) {
313 sym.st_name = 0;
314 sym.st_info =
315 GELF_ST_INFO(STB_LOCAL, STT_FUNC);
316 sym.st_other = 0;
317 sym.st_value = 0;
318 sym.st_size = Pstatus(pp->dpp_pr)->pr_dmodel ==
319 PR_MODEL_ILP32 ? -1U : -1ULL;
320
321 } else if (!strisglob(pp->dpp_mod)) {
322 return (dt_pid_error(dtp, pcb, dpr, NULL,
323 D_PROC_FUNC,
324 "failed to lookup '%s' in module '%s'",
325 pp->dpp_func, pp->dpp_mod));
326 } else {
327 return (0);
328 }
329 }
330
331 /*
332 * Only match defined functions of non-zero size.
333 */
334 if (GELF_ST_TYPE(sym.st_info) != STT_FUNC ||
335 sym.st_shndx == SHN_UNDEF || sym.st_size == 0)
336 return (0);
337
338 /*
339 * We don't instrument PLTs -- they're dynamically rewritten,
340 * and, so, inherently dicey to instrument.
341 */
342 if (Ppltdest(pp->dpp_pr, sym.st_value) != NULL)
343 return (0);
344
345 (void) Plookup_by_addr(pp->dpp_pr, sym.st_value, pp->dpp_func,
346 DTRACE_FUNCNAMELEN, &sym);
347
348 return (dt_pid_per_sym(pp, &sym, pp->dpp_func));
349 } else {
350 uint_t nmatches = pp->dpp_nmatches;
351
352 if (Psymbol_iter_by_addr(pp->dpp_pr, obj, PR_SYMTAB,
353 BIND_ANY | TYPE_FUNC, dt_pid_sym_filt, pp) == 1)
354 return (1);
355
356 if (nmatches == pp->dpp_nmatches) {
357 /*
358 * If we didn't match anything in the PR_SYMTAB, try
359 * the PR_DYNSYM.
360 */
361 if (Psymbol_iter_by_addr(pp->dpp_pr, obj, PR_DYNSYM,
362 BIND_ANY | TYPE_FUNC, dt_pid_sym_filt, pp) == 1)
363 return (1);
364 }
365 }
366
367 return (0);
368 }
369
370 static int
dt_pid_mod_filt(void * arg,const prmap_t * pmp,const char * obj)371 dt_pid_mod_filt(void *arg, const prmap_t *pmp, const char *obj)
372 {
373 char name[DTRACE_MODNAMELEN];
374 dt_pid_probe_t *pp = arg;
375
376 if ((pp->dpp_obj = strrchr(obj, '/')) == NULL)
377 pp->dpp_obj = obj;
378 else
379 pp->dpp_obj++;
380
381 if (gmatch(pp->dpp_obj, pp->dpp_mod))
382 return (dt_pid_per_mod(pp, pmp, obj));
383
384 (void) Plmid(pp->dpp_pr, pmp->pr_vaddr, &pp->dpp_lmid);
385
386 dt_pid_objname(name, sizeof (name), pp->dpp_lmid, pp->dpp_obj);
387
388 if (gmatch(name, pp->dpp_mod))
389 return (dt_pid_per_mod(pp, pmp, obj));
390
391 return (0);
392 }
393
394 static const prmap_t *
dt_pid_fix_mod(dtrace_probedesc_t * pdp,struct ps_prochandle * P)395 dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
396 {
397 char m[MAXPATHLEN];
398 Lmid_t lmid = PR_LMID_EVERY;
399 const char *obj;
400 const prmap_t *pmp;
401
402 /*
403 * Pick apart the link map from the library name.
404 */
405 if (strchr(pdp->dtpd_mod, '`') != NULL) {
406 char *end;
407
408 if (strncmp(pdp->dtpd_mod, "LM", 2) != 0 ||
409 !isdigit(pdp->dtpd_mod[2]))
410 return (NULL);
411
412 lmid = strtoul(&pdp->dtpd_mod[2], &end, 16);
413
414 obj = end + 1;
415
416 if (*end != '`' || strchr(obj, '`') != NULL)
417 return (NULL);
418
419 } else {
420 obj = pdp->dtpd_mod;
421 }
422
423 if ((pmp = Plmid_to_map(P, lmid, obj)) == NULL)
424 return (NULL);
425
426 (void) Pobjname(P, pmp->pr_vaddr, m, sizeof (m));
427 if ((obj = strrchr(m, '/')) == NULL)
428 obj = &m[0];
429 else
430 obj++;
431
432 (void) Plmid(P, pmp->pr_vaddr, &lmid);
433 dt_pid_objname(pdp->dtpd_mod, sizeof (pdp->dtpd_mod), lmid, obj);
434
435 return (pmp);
436 }
437
438
439 static int
dt_pid_create_pid_probes(dtrace_probedesc_t * pdp,dtrace_hdl_t * dtp,dt_pcb_t * pcb,dt_proc_t * dpr)440 dt_pid_create_pid_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
441 dt_pcb_t *pcb, dt_proc_t *dpr)
442 {
443 dt_pid_probe_t pp;
444 int ret = 0;
445
446 pp.dpp_dtp = dtp;
447 pp.dpp_dpr = dpr;
448 pp.dpp_pr = dpr->dpr_proc;
449 pp.dpp_pcb = pcb;
450
451 /*
452 * We can only trace dynamically-linked executables (since we've
453 * hidden some magic in ld.so.1 as well as libc.so.1).
454 */
455 if (Pname_to_map(pp.dpp_pr, PR_OBJ_LDSO) == NULL) {
456 return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_DYN,
457 "process %s is not a dynamically-linked executable",
458 &pdp->dtpd_provider[3]));
459 }
460
461 pp.dpp_mod = pdp->dtpd_mod[0] != '\0' ? pdp->dtpd_mod : "*";
462 pp.dpp_func = pdp->dtpd_func[0] != '\0' ? pdp->dtpd_func : "*";
463 pp.dpp_name = pdp->dtpd_name[0] != '\0' ? pdp->dtpd_name : "*";
464 pp.dpp_last_taken = 0;
465
466 if (strcmp(pp.dpp_func, "-") == 0) {
467 const prmap_t *aout, *pmp;
468
469 if (pdp->dtpd_mod[0] == '\0') {
470 pp.dpp_mod = pdp->dtpd_mod;
471 (void) strcpy(pdp->dtpd_mod, "a.out");
472 } else if (strisglob(pp.dpp_mod) ||
473 (aout = Pname_to_map(pp.dpp_pr, "a.out")) == NULL ||
474 (pmp = Pname_to_map(pp.dpp_pr, pp.dpp_mod)) == NULL ||
475 aout->pr_vaddr != pmp->pr_vaddr) {
476 return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_LIB,
477 "only the a.out module is valid with the "
478 "'-' function"));
479 }
480
481 if (strisglob(pp.dpp_name)) {
482 return (dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_NAME,
483 "only individual addresses may be specified "
484 "with the '-' function"));
485 }
486 }
487
488 /*
489 * If pp.dpp_mod contains any globbing meta-characters, we need
490 * to iterate over each module and compare its name against the
491 * pattern. An empty module name is treated as '*'.
492 */
493 if (strisglob(pp.dpp_mod)) {
494 ret = Pobject_iter(pp.dpp_pr, dt_pid_mod_filt, &pp);
495 } else {
496 const prmap_t *pmp;
497 char *obj;
498
499 /*
500 * If we can't find a matching module, don't sweat it -- either
501 * we'll fail the enabling because the probes don't exist or
502 * we'll wait for that module to come along.
503 */
504 if ((pmp = dt_pid_fix_mod(pdp, pp.dpp_pr)) != NULL) {
505 if ((obj = strchr(pdp->dtpd_mod, '`')) == NULL)
506 obj = pdp->dtpd_mod;
507 else
508 obj++;
509
510 ret = dt_pid_per_mod(&pp, pmp, obj);
511 }
512 }
513
514 return (ret);
515 }
516
517 static int
dt_pid_usdt_mapping(void * data,const prmap_t * pmp,const char * oname)518 dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
519 {
520 struct ps_prochandle *P = data;
521 GElf_Sym sym;
522 prsyminfo_t sip;
523 dof_helper_t dh;
524 GElf_Half e_type;
525 const char *mname;
526 const char *syms[] = { "___SUNW_dof", "__SUNW_dof" };
527 int i, fd = -1;
528
529 /*
530 * The symbol ___SUNW_dof is for lazy-loaded DOF sections, and
531 * __SUNW_dof is for actively-loaded DOF sections. We try to force
532 * in both types of DOF section since the process may not yet have
533 * run the code to instantiate these providers.
534 */
535 for (i = 0; i < 2; i++) {
536 if (Pxlookup_by_name(P, PR_LMID_EVERY, oname, syms[i], &sym,
537 &sip) != 0) {
538 continue;
539 }
540
541 if ((mname = strrchr(oname, '/')) == NULL)
542 mname = oname;
543 else
544 mname++;
545
546 dt_dprintf("lookup of %s succeeded for %s\n", syms[i], mname);
547
548 if (Pread(P, &e_type, sizeof (e_type), pmp->pr_vaddr +
549 offsetof(Elf64_Ehdr, e_type)) != sizeof (e_type)) {
550 dt_dprintf("read of ELF header failed");
551 continue;
552 }
553
554 dh.dofhp_dof = sym.st_value;
555 dh.dofhp_addr = (e_type == ET_EXEC) ? 0 : pmp->pr_vaddr;
556
557 dt_pid_objname(dh.dofhp_mod, sizeof (dh.dofhp_mod),
558 sip.prs_lmid, mname);
559
560 if (fd == -1 &&
561 (fd = pr_open(P, "/dev/dtrace/helper", O_RDWR, 0)) < 0) {
562 dt_dprintf("pr_open of helper device failed: %s\n",
563 strerror(errno));
564 return (-1); /* errno is set for us */
565 }
566
567 if (pr_ioctl(P, fd, DTRACEHIOC_ADDDOF, &dh, sizeof (dh)) < 0)
568 dt_dprintf("DOF was rejected for %s\n", dh.dofhp_mod);
569 }
570
571 if (fd != -1)
572 (void) pr_close(P, fd);
573
574 return (0);
575 }
576
577 static int
dt_pid_create_usdt_probes(dtrace_probedesc_t * pdp,dtrace_hdl_t * dtp,dt_pcb_t * pcb,dt_proc_t * dpr)578 dt_pid_create_usdt_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp,
579 dt_pcb_t *pcb, dt_proc_t *dpr)
580 {
581 struct ps_prochandle *P = dpr->dpr_proc;
582 int ret = 0;
583
584 assert(MUTEX_HELD(&dpr->dpr_lock));
585
586 (void) Pupdate_maps(P);
587 if (Pobject_iter(P, dt_pid_usdt_mapping, P) != 0) {
588 ret = -1;
589 (void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_USDT,
590 "failed to instantiate probes for pid %d: %s",
591 (int)Pstatus(P)->pr_pid, strerror(errno));
592 }
593
594 /*
595 * Put the module name in its canonical form.
596 */
597 (void) dt_pid_fix_mod(pdp, P);
598
599 return (ret);
600 }
601
602 static pid_t
dt_pid_get_pid(dtrace_probedesc_t * pdp,dtrace_hdl_t * dtp,dt_pcb_t * pcb,dt_proc_t * dpr)603 dt_pid_get_pid(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp, dt_pcb_t *pcb,
604 dt_proc_t *dpr)
605 {
606 pid_t pid;
607 char *c, *last = NULL, *end;
608
609 for (c = &pdp->dtpd_provider[0]; *c != '\0'; c++) {
610 if (!isdigit(*c))
611 last = c;
612 }
613
614 if (last == NULL || (*(++last) == '\0')) {
615 (void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_BADPROV,
616 "'%s' is not a valid provider", pdp->dtpd_provider);
617 return (-1);
618 }
619
620 errno = 0;
621 pid = strtol(last, &end, 10);
622
623 if (errno != 0 || end == last || end[0] != '\0' || pid <= 0) {
624 (void) dt_pid_error(dtp, pcb, dpr, NULL, D_PROC_BADPID,
625 "'%s' does not contain a valid pid", pdp->dtpd_provider);
626 return (-1);
627 }
628
629 return (pid);
630 }
631
632 int
dt_pid_create_probes(dtrace_probedesc_t * pdp,dtrace_hdl_t * dtp,dt_pcb_t * pcb)633 dt_pid_create_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp, dt_pcb_t *pcb)
634 {
635 char provname[DTRACE_PROVNAMELEN];
636 struct ps_prochandle *P;
637 dt_proc_t *dpr;
638 pid_t pid;
639 int err = 0;
640
641 assert(pcb != NULL);
642
643 if ((pid = dt_pid_get_pid(pdp, dtp, pcb, NULL)) == -1)
644 return (-1);
645
646 if (dtp->dt_ftfd == -1) {
647 if (dtp->dt_fterr == ENOENT) {
648 (void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_NODEV,
649 "pid provider is not installed on this system");
650 } else {
651 (void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_NODEV,
652 "pid provider is not available: %s",
653 strerror(dtp->dt_fterr));
654 }
655
656 return (-1);
657 }
658
659 (void) snprintf(provname, sizeof (provname), "pid%d", (int)pid);
660
661 if (gmatch(provname, pdp->dtpd_provider) != 0) {
662 if ((P = dt_proc_grab(dtp, pid, PGRAB_RDONLY | PGRAB_FORCE,
663 0)) == NULL) {
664 (void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_GRAB,
665 "failed to grab process %d", (int)pid);
666 return (-1);
667 }
668
669 dpr = dt_proc_lookup(dtp, P, 0);
670 assert(dpr != NULL);
671 (void) pthread_mutex_lock(&dpr->dpr_lock);
672
673 if ((err = dt_pid_create_pid_probes(pdp, dtp, pcb, dpr)) == 0) {
674 /*
675 * Alert other retained enablings which may match
676 * against the newly created probes.
677 */
678 (void) dt_ioctl(dtp, DTRACEIOC_ENABLE, NULL);
679 }
680
681 (void) pthread_mutex_unlock(&dpr->dpr_lock);
682 dt_proc_release(dtp, P);
683 }
684
685 /*
686 * If it's not strictly a pid provider, we might match a USDT provider.
687 */
688 if (strcmp(provname, pdp->dtpd_provider) != 0) {
689 if ((P = dt_proc_grab(dtp, pid, 0, 1)) == NULL) {
690 (void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_GRAB,
691 "failed to grab process %d", (int)pid);
692 return (-1);
693 }
694
695 dpr = dt_proc_lookup(dtp, P, 0);
696 assert(dpr != NULL);
697 (void) pthread_mutex_lock(&dpr->dpr_lock);
698
699 if (!dpr->dpr_usdt) {
700 err = dt_pid_create_usdt_probes(pdp, dtp, pcb, dpr);
701 dpr->dpr_usdt = B_TRUE;
702 }
703
704 (void) pthread_mutex_unlock(&dpr->dpr_lock);
705 dt_proc_release(dtp, P);
706 }
707
708 return (err ? -1 : 0);
709 }
710
711 int
dt_pid_create_probes_module(dtrace_hdl_t * dtp,dt_proc_t * dpr)712 dt_pid_create_probes_module(dtrace_hdl_t *dtp, dt_proc_t *dpr)
713 {
714 dtrace_prog_t *pgp;
715 dt_stmt_t *stp;
716 dtrace_probedesc_t *pdp, pd;
717 pid_t pid;
718 int ret = 0, found = B_FALSE;
719 char provname[DTRACE_PROVNAMELEN];
720
721 (void) snprintf(provname, sizeof (provname), "pid%d",
722 (int)dpr->dpr_pid);
723
724 for (pgp = dt_list_next(&dtp->dt_programs); pgp != NULL;
725 pgp = dt_list_next(pgp)) {
726
727 for (stp = dt_list_next(&pgp->dp_stmts); stp != NULL;
728 stp = dt_list_next(stp)) {
729
730 pdp = &stp->ds_desc->dtsd_ecbdesc->dted_probe;
731 pid = dt_pid_get_pid(pdp, dtp, NULL, dpr);
732 if (pid != dpr->dpr_pid)
733 continue;
734
735 found = B_TRUE;
736
737 pd = *pdp;
738
739 if (gmatch(provname, pdp->dtpd_provider) != 0 &&
740 dt_pid_create_pid_probes(&pd, dtp, NULL, dpr) != 0)
741 ret = 1;
742
743 /*
744 * If it's not strictly a pid provider, we might match
745 * a USDT provider.
746 */
747 if (strcmp(provname, pdp->dtpd_provider) != 0 &&
748 dt_pid_create_usdt_probes(&pd, dtp, NULL, dpr) != 0)
749 ret = 1;
750 }
751 }
752
753 if (found) {
754 /*
755 * Give DTrace a shot to the ribs to get it to check
756 * out the newly created probes.
757 */
758 (void) dt_ioctl(dtp, DTRACEIOC_ENABLE, NULL);
759 }
760
761 return (ret);
762 }
763
764 /*
765 * libdtrace has a backroom deal with us to ask us for type information on
766 * behalf of pid provider probes when fasttrap doesn't return any type
767 * information. Instead we'll look up the module and see if there is type
768 * information available. However, if there is no type information available due
769 * to a lack of CTF data, then we want to make sure that DTrace still carries on
770 * in face of that. As such we don't have a meaningful exit code about failure.
771 * We emit information about why we failed to the dtrace debug log so someone
772 * can figure it out by asking nicely for DTRACE_DEBUG.
773 */
774 void
dt_pid_get_types(dtrace_hdl_t * dtp,const dtrace_probedesc_t * pdp,dtrace_argdesc_t * adp,int * nargs)775 dt_pid_get_types(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp,
776 dtrace_argdesc_t *adp, int *nargs)
777 {
778 dt_module_t *dmp;
779 ctf_file_t *fp;
780 ctf_funcinfo_t f;
781 ctf_id_t argv[32];
782 GElf_Sym sym;
783 prsyminfo_t si;
784 struct ps_prochandle *p;
785 int i, args;
786 char buf[DTRACE_ARGTYPELEN];
787 const char *mptr;
788 char *eptr;
789 int ret = 0;
790 int argc = sizeof (argv) / sizeof (ctf_id_t);
791 Lmid_t lmid;
792
793 /* Set up a potential outcome */
794 args = *nargs;
795 *nargs = 0;
796
797 /*
798 * If we don't have an entry or return probe then we can just stop right
799 * now as we don't have arguments for offset probes.
800 */
801 if (strcmp(pdp->dtpd_name, "entry") != 0 &&
802 strcmp(pdp->dtpd_name, "return") != 0)
803 return;
804
805 dmp = dt_module_create(dtp, pdp->dtpd_provider);
806 if (dmp == NULL) {
807 dt_dprintf("failed to find module for %s\n",
808 pdp->dtpd_provider);
809 return;
810 }
811 if (dt_module_load(dtp, dmp) != 0) {
812 dt_dprintf("failed to load module for %s\n",
813 pdp->dtpd_provider);
814 return;
815 }
816
817 /*
818 * We may be working with a module that doesn't have ctf. If that's the
819 * case then we just return now and move on with life.
820 */
821 fp = dt_module_getctflib(dtp, dmp, pdp->dtpd_mod);
822 if (fp == NULL) {
823 dt_dprintf("no ctf container for %s\n",
824 pdp->dtpd_mod);
825 return;
826 }
827 p = dt_proc_grab(dtp, dmp->dm_pid, 0, PGRAB_RDONLY | PGRAB_FORCE);
828 if (p == NULL) {
829 dt_dprintf("failed to grab pid\n");
830 return;
831 }
832 dt_proc_lock(dtp, p);
833
834 /*
835 * Check to see if the D module has a link map ID and separate that out
836 * for properly interrogating libproc.
837 */
838 if ((mptr = strchr(pdp->dtpd_mod, '`')) != NULL) {
839 if (strlen(pdp->dtpd_mod) < 3) {
840 dt_dprintf("found weird modname with linkmap, "
841 "aborting: %s\n", pdp->dtpd_mod);
842 goto out;
843 }
844 if (pdp->dtpd_mod[0] != 'L' || pdp->dtpd_mod[1] != 'M') {
845 dt_dprintf("missing leading 'LM', "
846 "aborting: %s\n", pdp->dtpd_mod);
847 goto out;
848 }
849 errno = 0;
850 lmid = strtol(pdp->dtpd_mod + 2, &eptr, 16);
851 if (errno == ERANGE || eptr != mptr) {
852 dt_dprintf("failed to parse out lmid, aborting: %s\n",
853 pdp->dtpd_mod);
854 goto out;
855 }
856 mptr++;
857 } else {
858 mptr = pdp->dtpd_mod;
859 lmid = 0;
860 }
861
862 if (Pxlookup_by_name(p, lmid, mptr, pdp->dtpd_func,
863 &sym, &si) != 0) {
864 dt_dprintf("failed to find function %s in %s`%s\n",
865 pdp->dtpd_func, pdp->dtpd_provider, pdp->dtpd_mod);
866 goto out;
867 }
868 if (ctf_func_info(fp, si.prs_id, &f) == CTF_ERR) {
869 dt_dprintf("failed to get ctf information for %s in %s`%s\n",
870 pdp->dtpd_func, pdp->dtpd_provider, pdp->dtpd_mod);
871 goto out;
872 }
873
874 (void) snprintf(buf, sizeof (buf), "%s`%s", pdp->dtpd_provider,
875 pdp->dtpd_mod);
876
877 if (strcmp(pdp->dtpd_name, "return") == 0) {
878 if (args < 2)
879 goto out;
880
881 bzero(adp, sizeof (dtrace_argdesc_t));
882 adp->dtargd_ndx = 0;
883 adp->dtargd_id = pdp->dtpd_id;
884 adp->dtargd_mapping = adp->dtargd_ndx;
885 /*
886 * We explicitly leave out the library here, we only care that
887 * it is some int. We are assuming that there is no ctf
888 * container in here that is lying about what an int is.
889 */
890 (void) snprintf(adp->dtargd_native, DTRACE_ARGTYPELEN,
891 "user %s`%s", pdp->dtpd_provider, "int");
892 adp++;
893 bzero(adp, sizeof (dtrace_argdesc_t));
894 adp->dtargd_ndx = 1;
895 adp->dtargd_id = pdp->dtpd_id;
896 adp->dtargd_mapping = adp->dtargd_ndx;
897 ret = snprintf(adp->dtargd_native, DTRACE_ARGTYPELEN,
898 "userland ");
899 (void) ctf_type_qname(fp, f.ctc_return, adp->dtargd_native +
900 ret, DTRACE_ARGTYPELEN - ret, buf);
901 *nargs = 2;
902 } else {
903 if (ctf_func_args(fp, si.prs_id, argc, argv) == CTF_ERR)
904 goto out;
905
906 *nargs = MIN(args, f.ctc_argc);
907 for (i = 0; i < *nargs; i++, adp++) {
908 bzero(adp, sizeof (dtrace_argdesc_t));
909 adp->dtargd_ndx = i;
910 adp->dtargd_id = pdp->dtpd_id;
911 adp->dtargd_mapping = adp->dtargd_ndx;
912 ret = snprintf(adp->dtargd_native, DTRACE_ARGTYPELEN,
913 "userland ");
914 (void) ctf_type_qname(fp, argv[i], adp->dtargd_native +
915 ret, DTRACE_ARGTYPELEN - ret, buf);
916 }
917 }
918 out:
919 dt_proc_unlock(dtp, p);
920 dt_proc_release(dtp, p);
921 }
922