/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2005 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "libproc.h" #include "Pcontrol.h" #include "Putil.h" static file_info_t *build_map_symtab(struct ps_prochandle *, map_info_t *); static map_info_t *exec_map(struct ps_prochandle *); static map_info_t *object_to_map(struct ps_prochandle *, Lmid_t, const char *); static map_info_t *object_name_to_map(struct ps_prochandle *, Lmid_t, const char *); static GElf_Sym *sym_by_name(sym_tbl_t *, const char *, GElf_Sym *, uint_t *); static int read_ehdr32(struct ps_prochandle *, Elf32_Ehdr *, uintptr_t); #ifdef _LP64 static int read_ehdr64(struct ps_prochandle *, Elf64_Ehdr *, uintptr_t); #endif #define DATA_TYPES \ ((1 << STT_OBJECT) | (1 << STT_FUNC) | \ (1 << STT_COMMON) | (1 << STT_TLS)) #define IS_DATA_TYPE(tp) (((1 << (tp)) & DATA_TYPES) != 0) #define MA_RWX (MA_READ | MA_WRITE | MA_EXEC) typedef enum { PRO_NATURAL, PRO_BYADDR, PRO_BYNAME } pr_order_t; static int addr_cmp(const void *aa, const void *bb) { uintptr_t a = *((uintptr_t *)aa); uintptr_t b = *((uintptr_t *)bb); if (a > b) return (1); if (a < b) return (-1); return (0); } /* * Allocation function for a new file_info_t */ static file_info_t * file_info_new(struct ps_prochandle *P, map_info_t *mptr) { file_info_t *fptr; map_info_t *mp; uintptr_t a, addr, *addrs, last = 0; uint_t i, j, naddrs = 0, unordered = 0; if ((fptr = calloc(1, sizeof (file_info_t))) == NULL) return (NULL); list_link(fptr, &P->file_head); (void) strcpy(fptr->file_pname, mptr->map_pmap.pr_mapname); mptr->map_file = fptr; fptr->file_ref = 1; fptr->file_fd = -1; P->num_files++; /* * To figure out which map_info_t instances correspond to the mappings * for this load object, we look at the in-memory ELF image in the * base mapping (usually the program text). We examine the program * headers to find the addresses at the beginning and end of each * section and store them in a list which we then sort. Finally, we * walk down the list of addresses and the list of map_info_t * instances in lock step to correctly find the mappings that * correspond to this load object. */ if (P->status.pr_dmodel == PR_MODEL_ILP32) { Elf32_Ehdr ehdr; Elf32_Phdr phdr; if (read_ehdr32(P, &ehdr, mptr->map_pmap.pr_vaddr) != 0) return (fptr); addrs = malloc(sizeof (uintptr_t) * ehdr.e_phnum * 2); a = mptr->map_pmap.pr_vaddr + ehdr.e_phoff; for (i = 0; i < ehdr.e_phnum; i++, a += ehdr.e_phentsize) { if (Pread(P, &phdr, sizeof (phdr), a) != sizeof (phdr)) goto out; if (phdr.p_type != PT_LOAD || phdr.p_memsz == 0) continue; addr = phdr.p_vaddr; if (ehdr.e_type == ET_DYN) addr += mptr->map_pmap.pr_vaddr; if (last > addr) unordered = 1; addrs[naddrs++] = addr; addrs[naddrs++] = last = addr + phdr.p_memsz - 1; } #ifdef _LP64 } else { Elf64_Ehdr ehdr; Elf64_Phdr phdr; if (read_ehdr64(P, &ehdr, mptr->map_pmap.pr_vaddr) != 0) return (fptr); addrs = malloc(sizeof (uintptr_t) * ehdr.e_phnum * 2); a = mptr->map_pmap.pr_vaddr + ehdr.e_phoff; for (i = 0; i < ehdr.e_phnum; i++, a += ehdr.e_phentsize) { if (Pread(P, &phdr, sizeof (phdr), a) != sizeof (phdr)) goto out; if (phdr.p_type != PT_LOAD || phdr.p_memsz == 0) continue; addr = phdr.p_vaddr; if (ehdr.e_type == ET_DYN) addr += mptr->map_pmap.pr_vaddr; if (last > addr) unordered = 1; addrs[naddrs++] = addr; addrs[naddrs++] = last = addr + phdr.p_memsz - 1; } #endif } if (unordered) qsort(addrs, naddrs, sizeof (uintptr_t), addr_cmp); i = j = 0; mp = P->mappings; while (j < P->map_count && i < naddrs) { addr = addrs[i]; if (addr >= mp->map_pmap.pr_vaddr && addr < mp->map_pmap.pr_vaddr + mp->map_pmap.pr_size && mp->map_file == NULL) { mp->map_file = fptr; fptr->file_ref++; } if (addr < mp->map_pmap.pr_vaddr + mp->map_pmap.pr_size) { i++; } else { mp++; j++; } } out: free(addrs); return (fptr); } /* * Deallocation function for a file_info_t */ static void file_info_free(struct ps_prochandle *P, file_info_t *fptr) { if (--fptr->file_ref == 0) { list_unlink(fptr); if (fptr->file_symtab.sym_elf) { (void) elf_end(fptr->file_symtab.sym_elf); free(fptr->file_symtab.sym_elfmem); } if (fptr->file_symtab.sym_byname) free(fptr->file_symtab.sym_byname); if (fptr->file_symtab.sym_byaddr) free(fptr->file_symtab.sym_byaddr); if (fptr->file_dynsym.sym_elf) { (void) elf_end(fptr->file_dynsym.sym_elf); free(fptr->file_dynsym.sym_elfmem); } if (fptr->file_dynsym.sym_byname) free(fptr->file_dynsym.sym_byname); if (fptr->file_dynsym.sym_byaddr) free(fptr->file_dynsym.sym_byaddr); if (fptr->file_lo) free(fptr->file_lo); if (fptr->file_lname) free(fptr->file_lname); if (fptr->file_elf) (void) elf_end(fptr->file_elf); if (fptr->file_elfmem != NULL) free(fptr->file_elfmem); if (fptr->file_fd >= 0) (void) close(fptr->file_fd); if (fptr->file_ctfp) { ctf_close(fptr->file_ctfp); free(fptr->file_ctf_buf); } free(fptr); P->num_files--; } } /* * Deallocation function for a map_info_t */ static void map_info_free(struct ps_prochandle *P, map_info_t *mptr) { file_info_t *fptr; if ((fptr = mptr->map_file) != NULL) { if (fptr->file_map == mptr) fptr->file_map = NULL; file_info_free(P, fptr); } if (P->execname && mptr == P->map_exec) { free(P->execname); P->execname = NULL; } if (P->auxv && (mptr == P->map_exec || mptr == P->map_ldso)) { free(P->auxv); P->auxv = NULL; P->nauxv = 0; } if (mptr == P->map_exec) P->map_exec = NULL; if (mptr == P->map_ldso) P->map_ldso = NULL; } /* * Call-back function for librtld_db to iterate through all of its shared * libraries. We use this to get the load object names for the mappings. */ static int map_iter(const rd_loadobj_t *lop, void *cd) { char buf[PATH_MAX]; struct ps_prochandle *P = cd; map_info_t *mptr; file_info_t *fptr; dprintf("encountered rd object at %p\n", (void *)lop->rl_base); if ((mptr = Paddr2mptr(P, lop->rl_base)) == NULL) return (1); /* Base address does not match any mapping */ if ((fptr = mptr->map_file) == NULL && (fptr = file_info_new(P, mptr)) == NULL) return (1); /* Failed to allocate a new file_info_t */ if ((fptr->file_lo == NULL) && (fptr->file_lo = malloc(sizeof (rd_loadobj_t))) == NULL) { file_info_free(P, fptr); return (1); /* Failed to allocate rd_loadobj_t */ } fptr->file_map = mptr; *fptr->file_lo = *lop; fptr->file_lo->rl_plt_base = fptr->file_plt_base; fptr->file_lo->rl_plt_size = fptr->file_plt_size; if (fptr->file_lname) { free(fptr->file_lname); fptr->file_lname = NULL; } if (Pread_string(P, buf, sizeof (buf), lop->rl_nameaddr) > 0) { if ((fptr->file_lname = strdup(buf)) != NULL) fptr->file_lbase = basename(fptr->file_lname); } dprintf("loaded rd object %s lmid %lx\n", fptr->file_lname ? fptr->file_lname : "", lop->rl_lmident); return (1); } static void map_set(struct ps_prochandle *P, map_info_t *mptr, const char *lname) { file_info_t *fptr; if ((fptr = mptr->map_file) == NULL && (fptr = file_info_new(P, mptr)) == NULL) return; /* Failed to allocate a new file_info_t */ fptr->file_map = mptr; if ((fptr->file_lo == NULL) && (fptr->file_lo = malloc(sizeof (rd_loadobj_t))) == NULL) { file_info_free(P, fptr); return; /* Failed to allocate rd_loadobj_t */ } (void) memset(fptr->file_lo, 0, sizeof (rd_loadobj_t)); fptr->file_lo->rl_base = mptr->map_pmap.pr_vaddr; fptr->file_lo->rl_bend = mptr->map_pmap.pr_vaddr + mptr->map_pmap.pr_size; fptr->file_lo->rl_plt_base = fptr->file_plt_base; fptr->file_lo->rl_plt_size = fptr->file_plt_size; if (fptr->file_lname) { free(fptr->file_lname); fptr->file_lname = NULL; } if ((fptr->file_lname = strdup(lname)) != NULL) fptr->file_lbase = basename(fptr->file_lname); } static void load_static_maps(struct ps_prochandle *P) { map_info_t *mptr; /* * Construct the map for the a.out. */ if ((mptr = object_name_to_map(P, PR_LMID_EVERY, PR_OBJ_EXEC)) != NULL) map_set(P, mptr, "a.out"); /* * If the dynamic linker exists for this process, * construct the map for it. */ if (Pgetauxval(P, AT_BASE) != -1L && (mptr = object_name_to_map(P, PR_LMID_EVERY, PR_OBJ_LDSO)) != NULL) map_set(P, mptr, "ld.so.1"); } /* * Go through all the address space mappings, validating or updating * the information already gathered, or gathering new information. * * This function is only called when we suspect that the mappings have changed * because this is the first time we're calling it or because of rtld activity. */ void Pupdate_maps(struct ps_prochandle *P) { char mapfile[64]; int mapfd; struct stat statb; prmap_t *Pmap = NULL; prmap_t *pmap; ssize_t nmap; int i; uint_t oldmapcount; map_info_t *newmap, *newp; map_info_t *mptr; if (P->info_valid) return; Preadauxvec(P); (void) sprintf(mapfile, "/proc/%d/map", (int)P->pid); if ((mapfd = open(mapfile, O_RDONLY)) < 0 || fstat(mapfd, &statb) != 0 || statb.st_size < sizeof (prmap_t) || (Pmap = malloc(statb.st_size)) == NULL || (nmap = pread(mapfd, Pmap, statb.st_size, 0L)) <= 0 || (nmap /= sizeof (prmap_t)) == 0) { if (Pmap != NULL) free(Pmap); if (mapfd >= 0) (void) close(mapfd); Preset_maps(P); /* utter failure; destroy tables */ return; } (void) close(mapfd); if ((newmap = calloc(1, nmap * sizeof (map_info_t))) == NULL) return; /* * We try to merge any file information we may have for existing * mappings, to avoid having to rebuild the file info. */ mptr = P->mappings; pmap = Pmap; newp = newmap; oldmapcount = P->map_count; for (i = 0; i < nmap; i++, pmap++, newp++) { if (oldmapcount == 0) { /* * We've exhausted all the old mappings. Every new * mapping should be added. */ newp->map_pmap = *pmap; } else if (pmap->pr_vaddr == mptr->map_pmap.pr_vaddr && pmap->pr_size == mptr->map_pmap.pr_size && pmap->pr_offset == mptr->map_pmap.pr_offset && (pmap->pr_mflags & ~(MA_BREAK | MA_STACK)) == (mptr->map_pmap.pr_mflags & ~(MA_BREAK | MA_STACK)) && pmap->pr_pagesize == mptr->map_pmap.pr_pagesize && pmap->pr_shmid == mptr->map_pmap.pr_shmid && strcmp(pmap->pr_mapname, mptr->map_pmap.pr_mapname) == 0) { /* * This mapping matches exactly. Copy over the old * mapping, taking care to get the latest flags. * Make sure the associated file_info_t is updated * appropriately. */ *newp = *mptr; if (P->map_exec == mptr) P->map_exec = newp; if (P->map_ldso == mptr) P->map_ldso = newp; newp->map_pmap.pr_mflags = pmap->pr_mflags; if (mptr->map_file != NULL && mptr->map_file->file_map == mptr) mptr->map_file->file_map = newp; oldmapcount--; mptr++; } else if (pmap->pr_vaddr + pmap->pr_size > mptr->map_pmap.pr_vaddr) { /* * The old mapping doesn't exist any more, remove it * from the list. */ map_info_free(P, mptr); oldmapcount--; i--; newp--; pmap--; mptr++; } else { /* * This is a new mapping, add it directly. */ newp->map_pmap = *pmap; } } /* * Free any old maps */ while (oldmapcount) { map_info_free(P, mptr); oldmapcount--; mptr++; } free(Pmap); if (P->mappings != NULL) free(P->mappings); P->mappings = newmap; P->map_count = P->map_alloc = nmap; P->info_valid = 1; /* * Consult librtld_db to get the load object * names for all of the shared libraries. */ if (P->rap != NULL) (void) rd_loadobj_iter(P->rap, map_iter, P); } /* * Update all of the mappings and rtld_db as if by Pupdate_maps(), and then * forcibly cache all of the symbol tables associated with all object files. */ void Pupdate_syms(struct ps_prochandle *P) { file_info_t *fptr = list_next(&P->file_head); int i; Pupdate_maps(P); for (i = 0; i < P->num_files; i++, fptr = list_next(fptr)) { Pbuild_file_symtab(P, fptr); (void) Pbuild_file_ctf(P, fptr); } } /* * Return the librtld_db agent handle for the victim process. * The handle will become invalid at the next successful exec() and the * client (caller of proc_rd_agent()) must not use it beyond that point. * If the process is already dead, we've already tried our best to * create the agent during core file initialization. */ rd_agent_t * Prd_agent(struct ps_prochandle *P) { if (P->rap == NULL && P->state != PS_DEAD && P->state != PS_IDLE) { Pupdate_maps(P); if (P->num_files == 0) load_static_maps(P); rd_log(_libproc_debug); if ((P->rap = rd_new(P)) != NULL) (void) rd_loadobj_iter(P->rap, map_iter, P); } return (P->rap); } /* * Return the prmap_t structure containing 'addr', but only if it * is in the dynamic linker's link map and is the text section. */ const prmap_t * Paddr_to_text_map(struct ps_prochandle *P, uintptr_t addr) { map_info_t *mptr; if (!P->info_valid) Pupdate_maps(P); if ((mptr = Paddr2mptr(P, addr)) != NULL) { file_info_t *fptr = build_map_symtab(P, mptr); const prmap_t *pmp = &mptr->map_pmap; if (fptr != NULL && fptr->file_lo != NULL && fptr->file_lo->rl_base >= pmp->pr_vaddr && fptr->file_lo->rl_base < pmp->pr_vaddr + pmp->pr_size) return (pmp); } return (NULL); } /* * Return the prmap_t structure containing 'addr' (no restrictions on * the type of mapping). */ const prmap_t * Paddr_to_map(struct ps_prochandle *P, uintptr_t addr) { map_info_t *mptr; if (!P->info_valid) Pupdate_maps(P); if ((mptr = Paddr2mptr(P, addr)) != NULL) return (&mptr->map_pmap); return (NULL); } /* * Convert a full or partial load object name to the prmap_t for its * corresponding primary text mapping. */ const prmap_t * Plmid_to_map(struct ps_prochandle *P, Lmid_t lmid, const char *name) { map_info_t *mptr; if (name == PR_OBJ_EVERY) return (NULL); /* A reasonable mistake */ if ((mptr = object_name_to_map(P, lmid, name)) != NULL) return (&mptr->map_pmap); return (NULL); } const prmap_t * Pname_to_map(struct ps_prochandle *P, const char *name) { return (Plmid_to_map(P, PR_LMID_EVERY, name)); } const rd_loadobj_t * Paddr_to_loadobj(struct ps_prochandle *P, uintptr_t addr) { map_info_t *mptr; if (!P->info_valid) Pupdate_maps(P); if ((mptr = Paddr2mptr(P, addr)) == NULL) return (NULL); /* * By building the symbol table, we implicitly bring the PLT * information up to date in the load object. */ (void) build_map_symtab(P, mptr); return (mptr->map_file->file_lo); } const rd_loadobj_t * Plmid_to_loadobj(struct ps_prochandle *P, Lmid_t lmid, const char *name) { map_info_t *mptr; if (name == PR_OBJ_EVERY) return (NULL); if ((mptr = object_name_to_map(P, lmid, name)) == NULL) return (NULL); /* * By building the symbol table, we implicitly bring the PLT * information up to date in the load object. */ (void) build_map_symtab(P, mptr); return (mptr->map_file->file_lo); } const rd_loadobj_t * Pname_to_loadobj(struct ps_prochandle *P, const char *name) { return (Plmid_to_loadobj(P, PR_LMID_EVERY, name)); } ctf_file_t * Pbuild_file_ctf(struct ps_prochandle *P, file_info_t *fptr) { ctf_sect_t ctdata, symtab, strtab; sym_tbl_t *symp; int err; if (fptr->file_ctfp != NULL) return (fptr->file_ctfp); Pbuild_file_symtab(P, fptr); if (fptr->file_ctf_size == 0) return (NULL); symp = fptr->file_ctf_dyn ? &fptr->file_dynsym : &fptr->file_symtab; if (symp->sym_data == NULL) return (NULL); /* * The buffer may alread be allocated if this is a core file that * contained CTF data for this file. */ if (fptr->file_ctf_buf == NULL) { fptr->file_ctf_buf = malloc(fptr->file_ctf_size); if (fptr->file_ctf_buf == NULL) { dprintf("failed to allocate ctf buffer\n"); return (NULL); } if (pread(fptr->file_fd, fptr->file_ctf_buf, fptr->file_ctf_size, fptr->file_ctf_off) != fptr->file_ctf_size) { free(fptr->file_ctf_buf); fptr->file_ctf_buf = NULL; dprintf("failed to read ctf data\n"); return (NULL); } } ctdata.cts_name = ".SUNW_ctf"; ctdata.cts_type = SHT_PROGBITS; ctdata.cts_flags = 0; ctdata.cts_data = fptr->file_ctf_buf; ctdata.cts_size = fptr->file_ctf_size; ctdata.cts_entsize = 1; ctdata.cts_offset = 0; symtab.cts_name = fptr->file_ctf_dyn ? ".dynsym" : ".symtab"; symtab.cts_type = symp->sym_hdr.sh_type; symtab.cts_flags = symp->sym_hdr.sh_flags; symtab.cts_data = symp->sym_data->d_buf; symtab.cts_size = symp->sym_hdr.sh_size; symtab.cts_entsize = symp->sym_hdr.sh_entsize; symtab.cts_offset = symp->sym_hdr.sh_offset; strtab.cts_name = fptr->file_ctf_dyn ? ".dynstr" : ".strtab"; strtab.cts_type = symp->sym_strhdr.sh_type; strtab.cts_flags = symp->sym_strhdr.sh_flags; strtab.cts_data = symp->sym_strs; strtab.cts_size = symp->sym_strhdr.sh_size; strtab.cts_entsize = symp->sym_strhdr.sh_entsize; strtab.cts_offset = symp->sym_strhdr.sh_offset; fptr->file_ctfp = ctf_bufopen(&ctdata, &symtab, &strtab, &err); if (fptr->file_ctfp == NULL) { free(fptr->file_ctf_buf); fptr->file_ctf_buf = NULL; return (NULL); } dprintf("loaded %lu bytes of CTF data for %s\n", (ulong_t)fptr->file_ctf_size, fptr->file_pname); return (fptr->file_ctfp); } ctf_file_t * Paddr_to_ctf(struct ps_prochandle *P, uintptr_t addr) { map_info_t *mptr; file_info_t *fptr; if (!P->info_valid) Pupdate_maps(P); if ((mptr = Paddr2mptr(P, addr)) == NULL || (fptr = mptr->map_file) == NULL) return (NULL); return (Pbuild_file_ctf(P, fptr)); } ctf_file_t * Plmid_to_ctf(struct ps_prochandle *P, Lmid_t lmid, const char *name) { map_info_t *mptr; file_info_t *fptr; if (name == PR_OBJ_EVERY) return (NULL); if ((mptr = object_name_to_map(P, lmid, name)) == NULL || (fptr = mptr->map_file) == NULL) return (NULL); return (Pbuild_file_ctf(P, fptr)); } ctf_file_t * Pname_to_ctf(struct ps_prochandle *P, const char *name) { return (Plmid_to_ctf(P, PR_LMID_EVERY, name)); } /* * If we're not a core file, re-read the /proc//auxv file and store * its contents in P->auxv. In the case of a core file, we either * initialized P->auxv in Pcore() from the NT_AUXV, or we don't have an * auxv because the note was missing. */ void Preadauxvec(struct ps_prochandle *P) { char auxfile[64]; struct stat statb; ssize_t naux; int fd; if (P->state == PS_DEAD) return; /* Already read during Pgrab_core() */ if (P->state == PS_IDLE) return; /* No aux vec for Pgrab_file() */ if (P->auxv != NULL) { free(P->auxv); P->auxv = NULL; P->nauxv = 0; } (void) sprintf(auxfile, "/proc/%d/auxv", (int)P->pid); if ((fd = open(auxfile, O_RDONLY)) < 0) return; if (fstat(fd, &statb) == 0 && statb.st_size >= sizeof (auxv_t) && (P->auxv = malloc(statb.st_size + sizeof (auxv_t))) != NULL) { if ((naux = read(fd, P->auxv, statb.st_size)) < 0 || (naux /= sizeof (auxv_t)) < 1) { free(P->auxv); P->auxv = NULL; } else { P->auxv[naux].a_type = AT_NULL; P->auxv[naux].a_un.a_val = 0L; P->nauxv = (int)naux; } } (void) close(fd); } /* * Return a requested element from the process's aux vector. * Return -1 on failure (this is adequate for our purposes). */ long Pgetauxval(struct ps_prochandle *P, int type) { auxv_t *auxv; if (P->auxv == NULL) Preadauxvec(P); if (P->auxv == NULL) return (-1); for (auxv = P->auxv; auxv->a_type != AT_NULL; auxv++) { if (auxv->a_type == type) return (auxv->a_un.a_val); } return (-1); } /* * Return a pointer to our internal copy of the process's aux vector. * The caller should not hold on to this pointer across any libproc calls. */ const auxv_t * Pgetauxvec(struct ps_prochandle *P) { static const auxv_t empty = { AT_NULL, 0L }; if (P->auxv == NULL) Preadauxvec(P); if (P->auxv == NULL) return (&empty); return (P->auxv); } /* * Find or build the symbol table for the given mapping. */ static file_info_t * build_map_symtab(struct ps_prochandle *P, map_info_t *mptr) { prmap_t *pmap = &mptr->map_pmap; file_info_t *fptr; rd_loadobj_t *lop; uint_t i; if ((fptr = mptr->map_file) != NULL) { Pbuild_file_symtab(P, fptr); return (fptr); } if (pmap->pr_mapname[0] == '\0') return (NULL); /* * Attempt to find a matching file. * (A file can be mapped at several different addresses.) */ for (i = 0, fptr = list_next(&P->file_head); i < P->num_files; i++, fptr = list_next(fptr)) { if (strcmp(fptr->file_pname, pmap->pr_mapname) == 0 && (lop = fptr->file_lo) != NULL && ((pmap->pr_vaddr <= lop->rl_base && lop->rl_base < pmap->pr_vaddr + pmap->pr_size) || (pmap->pr_vaddr <= lop->rl_data_base && lop->rl_data_base < pmap->pr_vaddr + pmap->pr_size))) { mptr->map_file = fptr; fptr->file_ref++; Pbuild_file_symtab(P, fptr); return (fptr); } } /* * If we need to create a new file_info structure, iterate * through the load objects in order to attempt to connect * this new file with its primary text mapping. We again * need to handle ld.so as a special case because we need * to be able to bootstrap librtld_db. */ if ((fptr = file_info_new(P, mptr)) == NULL) return (NULL); if (P->map_ldso != mptr) { if (P->rap != NULL) (void) rd_loadobj_iter(P->rap, map_iter, P); else (void) Prd_agent(P); } else { fptr->file_map = mptr; } /* * If librtld_db wasn't able to help us connect the file to a primary * text mapping, set file_map to the current mapping because we require * fptr->file_map to be set in Pbuild_file_symtab. librtld_db may be * unaware of what's going on in the rare case that a legitimate ELF * file has been mmap(2)ed into the process address space *without* * the use of dlopen(3x). Why would this happen? See pwdx ... :) */ if (fptr->file_map == NULL) fptr->file_map = mptr; Pbuild_file_symtab(P, fptr); return (fptr); } static int read_ehdr32(struct ps_prochandle *P, Elf32_Ehdr *ehdr, uintptr_t addr) { if (Pread(P, ehdr, sizeof (*ehdr), addr) != sizeof (*ehdr)) return (-1); if (ehdr->e_ident[EI_MAG0] != ELFMAG0 || ehdr->e_ident[EI_MAG1] != ELFMAG1 || ehdr->e_ident[EI_MAG2] != ELFMAG2 || ehdr->e_ident[EI_MAG3] != ELFMAG3 || ehdr->e_ident[EI_CLASS] != ELFCLASS32 || #ifdef _BIG_ENDIAN ehdr->e_ident[EI_DATA] != ELFDATA2MSB || #else ehdr->e_ident[EI_DATA] != ELFDATA2LSB || #endif ehdr->e_ident[EI_VERSION] != EV_CURRENT) return (-1); return (0); } static int read_dynamic_phdr32(struct ps_prochandle *P, const Elf32_Ehdr *ehdr, Elf32_Phdr *phdr, uintptr_t addr) { uint_t i; for (i = 0; i < ehdr->e_phnum; i++) { uintptr_t a = addr + ehdr->e_phoff + i * ehdr->e_phentsize; if (Pread(P, phdr, sizeof (*phdr), a) != sizeof (*phdr)) return (-1); if (phdr->p_type == PT_DYNAMIC) return (0); } return (-1); } #ifdef _LP64 static int read_ehdr64(struct ps_prochandle *P, Elf64_Ehdr *ehdr, uintptr_t addr) { if (Pread(P, ehdr, sizeof (Elf64_Ehdr), addr) != sizeof (Elf64_Ehdr)) return (-1); if (ehdr->e_ident[EI_MAG0] != ELFMAG0 || ehdr->e_ident[EI_MAG1] != ELFMAG1 || ehdr->e_ident[EI_MAG2] != ELFMAG2 || ehdr->e_ident[EI_MAG3] != ELFMAG3 || ehdr->e_ident[EI_CLASS] != ELFCLASS64 || #ifdef _BIG_ENDIAN ehdr->e_ident[EI_DATA] != ELFDATA2MSB || #else ehdr->e_ident[EI_DATA] != ELFDATA2LSB || #endif ehdr->e_ident[EI_VERSION] != EV_CURRENT) return (-1); return (0); } static int read_dynamic_phdr64(struct ps_prochandle *P, const Elf64_Ehdr *ehdr, Elf64_Phdr *phdr, uintptr_t addr) { uint_t i; for (i = 0; i < ehdr->e_phnum; i++) { uintptr_t a = addr + ehdr->e_phoff + i * ehdr->e_phentsize; if (Pread(P, phdr, sizeof (*phdr), a) != sizeof (*phdr)) return (-1); if (phdr->p_type == PT_DYNAMIC) return (0); } return (-1); } #endif /* _LP64 */ /* * The text segment for each load object contains the elf header and * program headers. We can use this information to determine if the * file that corresponds to the load object is the same file that * was loaded into the process's address space. There can be a discrepency * if a file is recompiled after the process is started or if the target * represents a core file from a differently configured system -- two * common examples. The DT_CHECKSUM entry in the dynamic section * provides an easy method of comparison. It is important to note that * the dynamic section usually lives in the data segment, but the meta * data we use to find the dynamic section lives in the text segment so * if either of those segments is absent we can't proceed. * * We're looking through the elf file for several items: the symbol tables * (both dynsym and symtab), the procedure linkage table (PLT) base, * size, and relocation base, and the CTF information. Most of this can * be recovered from the loaded image of the file itself, the exceptions * being the symtab and CTF data. * * First we try to open the file that we think corresponds to the load * object, if the DT_CHECKSUM values match, we're all set, and can simply * recover all the information we need from the file. If the values of * DT_CHECKSUM don't match, or if we can't access the file for whatever * reasaon, we fake up a elf file to use in its stead. If we can't read * the elf data in the process's address space, we fall back to using * the file even though it may give inaccurate information. * * The elf file that we fake up has to consist of sections for the * dynsym, the PLT and the dynamic section. Note that in the case of a * core file, we'll get the CTF data in the file_info_t later on from * a section embedded the core file (if it's present). * * file_differs() conservatively looks for mismatched files, identifying * a match when there is any ambiguity (since that's the legacy behavior). */ static int file_differs(struct ps_prochandle *P, Elf *elf, file_info_t *fptr) { Elf_Scn *scn; GElf_Shdr shdr; GElf_Dyn dyn; Elf_Data *data; uint_t i, ndyn; GElf_Xword cksum; uintptr_t addr; if (fptr->file_map == NULL) return (0); if ((Pcontent(P) & (CC_CONTENT_TEXT | CC_CONTENT_DATA)) != (CC_CONTENT_TEXT | CC_CONTENT_DATA)) return (0); /* * First, we find the checksum value in the elf file. */ scn = NULL; while ((scn = elf_nextscn(elf, scn)) != NULL) { if (gelf_getshdr(scn, &shdr) != NULL && shdr.sh_type == SHT_DYNAMIC) goto found_shdr; } return (0); found_shdr: if ((data = elf_getdata(scn, NULL)) == NULL) return (0); if (P->status.pr_dmodel == PR_MODEL_ILP32) ndyn = shdr.sh_size / sizeof (Elf32_Dyn); #ifdef _LP64 else if (P->status.pr_dmodel == PR_MODEL_LP64) ndyn = shdr.sh_size / sizeof (Elf64_Dyn); #endif else return (0); for (i = 0; i < ndyn; i++) { if (gelf_getdyn(data, i, &dyn) != NULL && dyn.d_tag == DT_CHECKSUM) goto found_cksum; } return (0); found_cksum: cksum = dyn.d_un.d_val; dprintf("elf cksum value is %llx\n", (u_longlong_t)cksum); /* * Get the base of the text mapping that corresponds to this file. */ addr = fptr->file_map->map_pmap.pr_vaddr; if (P->status.pr_dmodel == PR_MODEL_ILP32) { Elf32_Ehdr ehdr; Elf32_Phdr phdr; Elf32_Dyn dync, *dynp; uint_t i; if (read_ehdr32(P, &ehdr, addr) != 0 || read_dynamic_phdr32(P, &ehdr, &phdr, addr) != 0) return (0); if (ehdr.e_type == ET_DYN) phdr.p_vaddr += addr; if ((dynp = malloc(phdr.p_filesz)) == NULL) return (0); dync.d_tag = DT_NULL; if (Pread(P, dynp, phdr.p_filesz, phdr.p_vaddr) != phdr.p_filesz) { free(dynp); return (0); } for (i = 0; i < phdr.p_filesz / sizeof (Elf32_Dyn); i++) { if (dynp[i].d_tag == DT_CHECKSUM) dync = dynp[i]; } free(dynp); if (dync.d_tag != DT_CHECKSUM) return (0); dprintf("image cksum value is %llx\n", (u_longlong_t)dync.d_un.d_val); return (dync.d_un.d_val != cksum); #ifdef _LP64 } else if (P->status.pr_dmodel == PR_MODEL_LP64) { Elf64_Ehdr ehdr; Elf64_Phdr phdr; Elf64_Dyn dync, *dynp; uint_t i; if (read_ehdr64(P, &ehdr, addr) != 0 || read_dynamic_phdr64(P, &ehdr, &phdr, addr) != 0) return (0); if (ehdr.e_type == ET_DYN) phdr.p_vaddr += addr; if ((dynp = malloc(phdr.p_filesz)) == NULL) return (0); dync.d_tag = DT_NULL; if (Pread(P, dynp, phdr.p_filesz, phdr.p_vaddr) != phdr.p_filesz) { free(dynp); return (0); } for (i = 0; i < phdr.p_filesz / sizeof (Elf64_Dyn); i++) { if (dynp[i].d_tag == DT_CHECKSUM) dync = dynp[i]; } free(dynp); if (dync.d_tag != DT_CHECKSUM) return (0); dprintf("image cksum value is %llx\n", (u_longlong_t)dync.d_un.d_val); return (dync.d_un.d_val != cksum); #endif /* _LP64 */ } return (0); } static Elf * fake_elf(struct ps_prochandle *P, file_info_t *fptr) { enum { DI_PLTGOT = 0, DI_JMPREL, DI_PLTRELSZ, DI_PLTREL, DI_SYMTAB, DI_HASH, DI_SYMENT, DI_STRTAB, DI_STRSZ, DI_NENT }; uintptr_t addr; size_t size = 0; caddr_t elfdata = NULL; Elf *elf; Elf32_Word nchain; static char shstr[] = ".shstrtab\0.dynsym\0.dynstr\0.dynamic\0.plt"; if (fptr->file_map == NULL) return (NULL); if ((Pcontent(P) & (CC_CONTENT_TEXT | CC_CONTENT_DATA)) != (CC_CONTENT_TEXT | CC_CONTENT_DATA)) return (NULL); addr = fptr->file_map->map_pmap.pr_vaddr; /* * We're building a in memory elf file that will let us use libelf * for most of the work we need to later (e.g. symbol table lookups). * We need sections for the dynsym, dynstr, and plt, and we need * the program headers from the text section. The former is used in * Pbuild_file_symtab(); the latter is used in several functions in * Pcore.c to reconstruct the origin of each mapping from the load * object that spawned it. * * Here are some useful pieces of elf trivia that will help * to elucidate this code. * * All the information we need about the dynstr can be found in these * two entries in the dynamic section: * * DT_STRTAB base of dynstr * DT_STRSZ size of dynstr * * So deciphering the dynstr is pretty straightforward. * * The dynsym is a little trickier. * * DT_SYMTAB base of dynsym * DT_SYMENT size of a dynstr entry (Elf{32,64}_Sym) * DT_HASH base of hash table for dynamic lookups * * The DT_SYMTAB entry gives us any easy way of getting to the base * of the dynsym, but getting the size involves rooting around in the * dynamic lookup hash table. Here's the layout of the hash table: * * +-------------------+ * | nbucket | All values are of type * +-------------------+ Elf32_Word * | nchain | * +-------------------+ * | bucket[0] | * | . . . | * | bucket[nbucket-1] | * +-------------------+ * | chain[0] | * | . . . | * | chain[nchain-1] | * +-------------------+ * (figure 5-12 from the SYS V Generic ABI) * * Symbols names are hashed into a particular bucket which contains * an index into the symbol table. Each entry in the symbol table * has a corresponding entry in the chain table which tells the * consumer where the next entry in the hash chain is. We can use * the nchain field to find out the size of the dynsym. * * We can figure out the size of the .plt section, but it takes some * doing. We need to use the following information: * * DT_PLTGOT base of the PLT * DT_JMPREL base of the PLT's relocation section * DT_PLTRELSZ size of the PLT's relocation section * DT_PLTREL type of the PLT's relocation section * * We can use the relocation section to figure out the address of the * last entry and subtract off the value of DT_PLTGOT to calculate * the size of the PLT. * * For more information, check out the System V Generic ABI. */ if (P->status.pr_dmodel == PR_MODEL_ILP32) { Elf32_Ehdr ehdr, *ep; Elf32_Phdr phdr; Elf32_Shdr *sp; Elf32_Dyn *dp; Elf32_Dyn *d[DI_NENT] = { 0 }; uint_t i, dcount = 0; uint32_t off; size_t pltsz = 0, pltentsz; if (read_ehdr32(P, &ehdr, addr) != 0 || read_dynamic_phdr32(P, &ehdr, &phdr, addr) != 0) return (NULL); if (ehdr.e_type == ET_DYN) phdr.p_vaddr += addr; if ((dp = malloc(phdr.p_filesz)) == NULL) return (NULL); if (Pread(P, dp, phdr.p_filesz, phdr.p_vaddr) != phdr.p_filesz) { free(dp); return (NULL); } for (i = 0; i < phdr.p_filesz / sizeof (Elf32_Dyn); i++) { switch (dp[i].d_tag) { /* * For the .plt section. */ case DT_PLTGOT: d[DI_PLTGOT] = &dp[i]; continue; case DT_JMPREL: d[DI_JMPREL] = &dp[i]; continue; case DT_PLTRELSZ: d[DI_PLTRELSZ] = &dp[i]; continue; case DT_PLTREL: d[DI_PLTREL] = &dp[i]; continue; default: continue; /* * For the .dynsym section. */ case DT_SYMTAB: d[DI_SYMTAB] = &dp[i]; break; case DT_HASH: d[DI_HASH] = &dp[i]; break; case DT_SYMENT: d[DI_SYMENT] = &dp[i]; break; /* * For the .dynstr section. */ case DT_STRTAB: d[DI_STRTAB] = &dp[i]; break; case DT_STRSZ: d[DI_STRSZ] = &dp[i]; break; } dcount++; } /* * We need all of those dynamic entries in order to put * together a complete set of elf sections, but we'll * let the PLT section slide if need be. The dynsym- and * dynstr-related dynamic entries are mandatory in both * executables and shared objects so if one of those is * missing, we're in some trouble and should abort. */ if (dcount + 4 != DI_NENT) { dprintf("text section missing required dynamic " "entries\n"); return (NULL); } if (ehdr.e_type == ET_DYN) { if (d[DI_PLTGOT] != NULL) d[DI_PLTGOT]->d_un.d_ptr += addr; if (d[DI_JMPREL] != NULL) d[DI_JMPREL]->d_un.d_ptr += addr; d[DI_SYMTAB]->d_un.d_ptr += addr; d[DI_HASH]->d_un.d_ptr += addr; d[DI_STRTAB]->d_un.d_ptr += addr; } /* elf header */ size = sizeof (Elf32_Ehdr); /* program headers from in-core elf fragment */ size += ehdr.e_phnum * ehdr.e_phentsize; /* unused shdr, and .shstrtab section */ size += sizeof (Elf32_Shdr); size += sizeof (Elf32_Shdr); size += roundup(sizeof (shstr), 4); /* .dynsym section */ size += sizeof (Elf32_Shdr); if (Pread(P, &nchain, sizeof (nchain), d[DI_HASH]->d_un.d_ptr + 4) != sizeof (nchain)) goto bad32; size += sizeof (Elf32_Sym) * nchain; /* .dynstr section */ size += sizeof (Elf32_Shdr); size += roundup(d[DI_STRSZ]->d_un.d_val, 4); /* .dynamic section */ size += sizeof (Elf32_Shdr); size += roundup(phdr.p_filesz, 4); /* .plt section */ if (d[DI_PLTGOT] != NULL && d[DI_JMPREL] != NULL && d[DI_PLTRELSZ] != NULL && d[DI_PLTREL] != NULL) { uintptr_t penult, ult; uintptr_t jmprel = d[DI_JMPREL]->d_un.d_ptr; size_t pltrelsz = d[DI_PLTRELSZ]->d_un.d_val; if (d[DI_PLTREL]->d_un.d_val == DT_RELA) { uint_t ndx = pltrelsz / sizeof (Elf32_Rela) - 2; Elf32_Rela r[2]; if (Pread(P, r, sizeof (r), jmprel + sizeof (r[0]) * ndx) != sizeof (r)) goto bad32; penult = r[0].r_offset; ult = r[1].r_offset; } else if (d[DI_PLTREL]->d_un.d_val == DT_REL) { uint_t ndx = pltrelsz / sizeof (Elf32_Rel) - 2; Elf32_Rel r[2]; if (Pread(P, r, sizeof (r), jmprel + sizeof (r[0]) * ndx) != sizeof (r)) goto bad32; penult = r[0].r_offset; ult = r[1].r_offset; } else { goto bad32; } pltentsz = ult - penult; if (ehdr.e_type == ET_DYN) ult += addr; pltsz = ult - d[DI_PLTGOT]->d_un.d_ptr + pltentsz; size += sizeof (Elf32_Shdr); size += roundup(pltsz, 4); } if ((elfdata = calloc(1, size)) == NULL) goto bad32; /* LINTED - alignment */ ep = (Elf32_Ehdr *)elfdata; (void) memcpy(ep, &ehdr, offsetof(Elf32_Ehdr, e_phoff)); ep->e_ehsize = sizeof (Elf32_Ehdr); ep->e_phoff = sizeof (Elf32_Ehdr); ep->e_phentsize = ehdr.e_phentsize; ep->e_phnum = ehdr.e_phnum; ep->e_shoff = ep->e_phoff + ep->e_phnum * ep->e_phentsize; ep->e_shentsize = sizeof (Elf32_Shdr); ep->e_shnum = (pltsz == 0) ? 5 : 6; ep->e_shstrndx = 1; /* LINTED - alignment */ sp = (Elf32_Shdr *)(elfdata + ep->e_shoff); off = ep->e_shoff + ep->e_shentsize * ep->e_shnum; /* * Copying the program headers directly from the process's * address space is a little suspect, but since we only * use them for their address and size values, this is fine. */ if (Pread(P, &elfdata[ep->e_phoff], ep->e_phnum * ep->e_phentsize, addr + ehdr.e_phoff) != ep->e_phnum * ep->e_phentsize) { free(elfdata); goto bad32; } /* * The first elf section is always skipped. */ sp++; /* * Section Header[1] sh_name: .shstrtab */ sp->sh_name = 0; sp->sh_type = SHT_STRTAB; sp->sh_flags = SHF_STRINGS; sp->sh_addr = 0; sp->sh_offset = off; sp->sh_size = sizeof (shstr); sp->sh_link = 0; sp->sh_info = 0; sp->sh_addralign = 1; sp->sh_entsize = 0; (void) memcpy(&elfdata[off], shstr, sizeof (shstr)); off += roundup(sp->sh_size, 4); sp++; /* * Section Header[2] sh_name: .dynsym */ sp->sh_name = 10; sp->sh_type = SHT_DYNSYM; sp->sh_flags = SHF_ALLOC; sp->sh_addr = d[DI_SYMTAB]->d_un.d_ptr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = nchain * sizeof (Elf32_Sym); sp->sh_link = 3; sp->sh_info = 1; sp->sh_addralign = 4; sp->sh_entsize = sizeof (Elf32_Sym); if (Pread(P, &elfdata[off], sp->sh_size, d[DI_SYMTAB]->d_un.d_ptr) != sp->sh_size) { free(elfdata); goto bad32; } off += roundup(sp->sh_size, 4); sp++; /* * Section Header[3] sh_name: .dynstr */ sp->sh_name = 18; sp->sh_type = SHT_STRTAB; sp->sh_flags = SHF_ALLOC | SHF_STRINGS; sp->sh_addr = d[DI_STRTAB]->d_un.d_ptr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = d[DI_STRSZ]->d_un.d_val; sp->sh_link = 0; sp->sh_info = 0; sp->sh_addralign = 1; sp->sh_entsize = 0; if (Pread(P, &elfdata[off], sp->sh_size, d[DI_STRTAB]->d_un.d_ptr) != sp->sh_size) { free(elfdata); goto bad32; } off += roundup(sp->sh_size, 4); sp++; /* * Section Header[4] sh_name: .dynamic */ sp->sh_name = 26; sp->sh_type = SHT_DYNAMIC; sp->sh_flags = SHF_WRITE | SHF_ALLOC; sp->sh_addr = phdr.p_vaddr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = phdr.p_filesz; sp->sh_link = 3; sp->sh_info = 0; sp->sh_addralign = 4; sp->sh_entsize = sizeof (Elf32_Dyn); (void) memcpy(&elfdata[off], dp, sp->sh_size); off += roundup(sp->sh_size, 4); sp++; /* * Section Header[5] sh_name: .plt */ if (pltsz != 0) { sp->sh_name = 35; sp->sh_type = SHT_PROGBITS; sp->sh_flags = SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR; sp->sh_addr = d[DI_PLTGOT]->d_un.d_ptr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = pltsz; sp->sh_link = 0; sp->sh_info = 0; sp->sh_addralign = 4; sp->sh_entsize = pltentsz; if (Pread(P, &elfdata[off], sp->sh_size, d[DI_PLTGOT]->d_un.d_ptr) != sp->sh_size) { free(elfdata); goto bad32; } off += roundup(sp->sh_size, 4); sp++; } free(dp); goto good; bad32: free(dp); return (NULL); #ifdef _LP64 } else if (P->status.pr_dmodel == PR_MODEL_LP64) { Elf64_Ehdr ehdr, *ep; Elf64_Phdr phdr; Elf64_Shdr *sp; Elf64_Dyn *dp; Elf64_Dyn *d[DI_NENT] = { 0 }; uint_t i, dcount = 0; uint64_t off; size_t pltsz = 0, pltentsz; if (read_ehdr64(P, &ehdr, addr) != 0 || read_dynamic_phdr64(P, &ehdr, &phdr, addr) != 0) return (NULL); if (ehdr.e_type == ET_DYN) phdr.p_vaddr += addr; if ((dp = malloc(phdr.p_filesz)) == NULL) return (NULL); if (Pread(P, dp, phdr.p_filesz, phdr.p_vaddr) != phdr.p_filesz) { free(dp); return (NULL); } for (i = 0; i < phdr.p_filesz / sizeof (Elf64_Dyn); i++) { switch (dp[i].d_tag) { /* * For the .plt section. */ case DT_PLTGOT: d[DI_PLTGOT] = &dp[i]; continue; case DT_JMPREL: d[DI_JMPREL] = &dp[i]; continue; case DT_PLTRELSZ: d[DI_PLTRELSZ] = &dp[i]; continue; case DT_PLTREL: d[DI_PLTREL] = &dp[i]; continue; default: continue; /* * For the .dynsym section. */ case DT_SYMTAB: d[DI_SYMTAB] = &dp[i]; break; case DT_HASH: d[DI_HASH] = &dp[i]; break; case DT_SYMENT: d[DI_SYMENT] = &dp[i]; break; /* * For the .dynstr section. */ case DT_STRTAB: d[DI_STRTAB] = &dp[i]; break; case DT_STRSZ: d[DI_STRSZ] = &dp[i]; break; } dcount++; } /* * We need all of those dynamic entries in order to put * together a complete set of elf sections, but we'll * let the PLT section slide if need be. The dynsym- and * dynstr-related dynamic entries are mandatory in both * executables and shared objects so if one of those is * missing, we're in some trouble and should abort. */ if (dcount + 4 != DI_NENT) { dprintf("text section missing required dynamic " "entries\n"); return (NULL); } if (ehdr.e_type == ET_DYN) { if (d[DI_PLTGOT] != NULL) d[DI_PLTGOT]->d_un.d_ptr += addr; if (d[DI_JMPREL] != NULL) d[DI_JMPREL]->d_un.d_ptr += addr; d[DI_SYMTAB]->d_un.d_ptr += addr; d[DI_HASH]->d_un.d_ptr += addr; d[DI_STRTAB]->d_un.d_ptr += addr; } /* elf header */ size = sizeof (Elf64_Ehdr); /* program headers from in-core elf fragment */ size += ehdr.e_phnum * ehdr.e_phentsize; /* unused shdr, and .shstrtab section */ size += sizeof (Elf64_Shdr); size += sizeof (Elf64_Shdr); size += roundup(sizeof (shstr), 8); /* .dynsym section */ size += sizeof (Elf64_Shdr); if (Pread(P, &nchain, sizeof (nchain), d[DI_HASH]->d_un.d_ptr + 4) != sizeof (nchain)) goto bad64; size += sizeof (Elf64_Sym) * nchain; /* .dynstr section */ size += sizeof (Elf64_Shdr); size += roundup(d[DI_STRSZ]->d_un.d_val, 8); /* .dynamic section */ size += sizeof (Elf64_Shdr); size += roundup(phdr.p_filesz, 8); /* .plt section */ if (d[DI_PLTGOT] != NULL && d[DI_JMPREL] != NULL && d[DI_PLTRELSZ] != NULL && d[DI_PLTREL] != NULL) { uintptr_t penult, ult; uintptr_t jmprel = d[DI_JMPREL]->d_un.d_ptr; size_t pltrelsz = d[DI_PLTRELSZ]->d_un.d_val; if (d[DI_PLTREL]->d_un.d_val == DT_RELA) { uint_t ndx = pltrelsz / sizeof (Elf64_Rela) - 2; Elf64_Rela r[2]; if (Pread(P, r, sizeof (r), jmprel + sizeof (r[0]) * ndx) != sizeof (r)) goto bad64; penult = r[0].r_offset; ult = r[1].r_offset; } else if (d[DI_PLTREL]->d_un.d_val == DT_REL) { uint_t ndx = pltrelsz / sizeof (Elf64_Rel) - 2; Elf64_Rel r[2]; if (Pread(P, r, sizeof (r), jmprel + sizeof (r[0]) * ndx) != sizeof (r)) goto bad64; penult = r[0].r_offset; ult = r[1].r_offset; } else { goto bad64; } pltentsz = ult - penult; if (ehdr.e_type == ET_DYN) ult += addr; pltsz = ult - d[DI_PLTGOT]->d_un.d_ptr + pltentsz; size += sizeof (Elf64_Shdr); size += roundup(pltsz, 8); } if ((elfdata = calloc(1, size)) == NULL) goto bad64; /* LINTED - alignment */ ep = (Elf64_Ehdr *)elfdata; (void) memcpy(ep, &ehdr, offsetof(Elf64_Ehdr, e_phoff)); ep->e_ehsize = sizeof (Elf64_Ehdr); ep->e_phoff = sizeof (Elf64_Ehdr); ep->e_phentsize = ehdr.e_phentsize; ep->e_phnum = ehdr.e_phnum; ep->e_shoff = ep->e_phoff + ep->e_phnum * ep->e_phentsize; ep->e_shentsize = sizeof (Elf64_Shdr); ep->e_shnum = (pltsz == 0) ? 5 : 6; ep->e_shstrndx = 1; /* LINTED - alignment */ sp = (Elf64_Shdr *)(elfdata + ep->e_shoff); off = ep->e_shoff + ep->e_shentsize * ep->e_shnum; /* * Copying the program headers directly from the process's * address space is a little suspect, but since we only * use them for their address and size values, this is fine. */ if (Pread(P, &elfdata[ep->e_phoff], ep->e_phnum * ep->e_phentsize, addr + ehdr.e_phoff) != ep->e_phnum * ep->e_phentsize) { free(elfdata); goto bad64; } /* * The first elf section is always skipped. */ sp++; /* * Section Header[1] sh_name: .shstrtab */ sp->sh_name = 0; sp->sh_type = SHT_STRTAB; sp->sh_flags = SHF_STRINGS; sp->sh_addr = 0; sp->sh_offset = off; sp->sh_size = sizeof (shstr); sp->sh_link = 0; sp->sh_info = 0; sp->sh_addralign = 1; sp->sh_entsize = 0; (void) memcpy(&elfdata[off], shstr, sizeof (shstr)); off += roundup(sp->sh_size, 8); sp++; /* * Section Header[2] sh_name: .dynsym */ sp->sh_name = 10; sp->sh_type = SHT_DYNSYM; sp->sh_flags = SHF_ALLOC; sp->sh_addr = d[DI_SYMTAB]->d_un.d_ptr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = nchain * sizeof (Elf64_Sym); sp->sh_link = 3; sp->sh_info = 1; sp->sh_addralign = 8; sp->sh_entsize = sizeof (Elf64_Sym); if (Pread(P, &elfdata[off], sp->sh_size, d[DI_SYMTAB]->d_un.d_ptr) != sp->sh_size) { free(elfdata); goto bad64; } off += roundup(sp->sh_size, 8); sp++; /* * Section Header[3] sh_name: .dynstr */ sp->sh_name = 18; sp->sh_type = SHT_STRTAB; sp->sh_flags = SHF_ALLOC | SHF_STRINGS; sp->sh_addr = d[DI_STRTAB]->d_un.d_ptr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = d[DI_STRSZ]->d_un.d_val; sp->sh_link = 0; sp->sh_info = 0; sp->sh_addralign = 1; sp->sh_entsize = 0; if (Pread(P, &elfdata[off], sp->sh_size, d[DI_STRTAB]->d_un.d_ptr) != sp->sh_size) { free(elfdata); goto bad64; } off += roundup(sp->sh_size, 8); sp++; /* * Section Header[4] sh_name: .dynamic */ sp->sh_name = 26; sp->sh_type = SHT_DYNAMIC; sp->sh_flags = SHF_WRITE | SHF_ALLOC; sp->sh_addr = phdr.p_vaddr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = phdr.p_filesz; sp->sh_link = 3; sp->sh_info = 0; sp->sh_addralign = 8; sp->sh_entsize = sizeof (Elf64_Dyn); (void) memcpy(&elfdata[off], dp, sp->sh_size); off += roundup(sp->sh_size, 8); sp++; /* * Section Header[5] sh_name: .plt */ if (pltsz != 0) { sp->sh_name = 35; sp->sh_type = SHT_PROGBITS; sp->sh_flags = SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR; sp->sh_addr = d[DI_PLTGOT]->d_un.d_ptr; if (ehdr.e_type == ET_DYN) sp->sh_addr -= addr; sp->sh_offset = off; sp->sh_size = pltsz; sp->sh_link = 0; sp->sh_info = 0; sp->sh_addralign = 8; sp->sh_entsize = pltentsz; if (Pread(P, &elfdata[off], sp->sh_size, d[DI_PLTGOT]->d_un.d_ptr) != sp->sh_size) { free(elfdata); goto bad64; } off += roundup(sp->sh_size, 8); sp++; } free(dp); goto good; bad64: free(dp); return (NULL); #endif /* _LP64 */ } good: if ((elf = elf_memory(elfdata, size)) == NULL) { free(elfdata); return (NULL); } fptr->file_elfmem = elfdata; return (elf); } /* * We wouldn't need these if qsort(3C) took an argument for the callback... */ static mutex_t sort_mtx = DEFAULTMUTEX; static char *sort_strs; static GElf_Sym *sort_syms; int byaddr_cmp_common(GElf_Sym *a, char *aname, GElf_Sym *b, char *bname) { if (a->st_value < b->st_value) return (-1); if (a->st_value > b->st_value) return (1); /* * Prefer the function to the non-function. */ if (GELF_ST_TYPE(a->st_info) != GELF_ST_TYPE(b->st_info)) { if (GELF_ST_TYPE(a->st_info) == STT_FUNC) return (-1); if (GELF_ST_TYPE(b->st_info) == STT_FUNC) return (1); } /* * Prefer the weak or strong global symbol to the local symbol. */ if (GELF_ST_BIND(a->st_info) != GELF_ST_BIND(b->st_info)) { if (GELF_ST_BIND(b->st_info) == STB_LOCAL) return (-1); if (GELF_ST_BIND(a->st_info) == STB_LOCAL) return (1); } /* * Prefer the name with fewer leading underscores in the name. */ while (*aname == '_' && *bname == '_') { aname++; bname++; } if (*bname == '_') return (-1); if (*aname == '_') return (1); /* * Prefer the symbol with the smaller size. */ if (a->st_size < b->st_size) return (-1); if (a->st_size > b->st_size) return (1); /* * All other factors being equal, fall back to lexicographic order. */ return (strcmp(aname, bname)); } static int byaddr_cmp(const void *aa, const void *bb) { GElf_Sym *a = &sort_syms[*(uint_t *)aa]; GElf_Sym *b = &sort_syms[*(uint_t *)bb]; char *aname = sort_strs + a->st_name; char *bname = sort_strs + b->st_name; return (byaddr_cmp_common(a, aname, b, bname)); } static int byname_cmp(const void *aa, const void *bb) { GElf_Sym *a = &sort_syms[*(uint_t *)aa]; GElf_Sym *b = &sort_syms[*(uint_t *)bb]; char *aname = sort_strs + a->st_name; char *bname = sort_strs + b->st_name; return (strcmp(aname, bname)); } void optimize_symtab(sym_tbl_t *symtab) { GElf_Sym *symp, *syms; uint_t i, *indexa, *indexb; Elf_Data *data; size_t symn, strsz, count; if (symtab == NULL || symtab->sym_data == NULL || symtab->sym_byaddr != NULL) return; data = symtab->sym_data; symn = symtab->sym_symn; strsz = symtab->sym_strsz; symp = syms = malloc(sizeof (GElf_Sym) * symn); /* * First record all the symbols into a table and count up the ones * that we're interested in. We mark symbols as invalid by setting * the st_name to an illegal value. */ for (i = 0, count = 0; i < symn; i++, symp++) { if (gelf_getsym(data, i, symp) != NULL && symp->st_name < strsz && IS_DATA_TYPE(GELF_ST_TYPE(symp->st_info))) count++; else symp->st_name = strsz; } /* * Allocate sufficient space for both tables and populate them * with the same symbols we just counted. */ symtab->sym_count = count; indexa = symtab->sym_byaddr = calloc(sizeof (uint_t), count); indexb = symtab->sym_byname = calloc(sizeof (uint_t), count); for (i = 0, symp = syms; i < symn; i++, symp++) { if (symp->st_name < strsz) *indexa++ = *indexb++ = i; } /* * Sort the two tables according to the appropriate criteria. */ (void) mutex_lock(&sort_mtx); sort_strs = symtab->sym_strs; sort_syms = syms; qsort(symtab->sym_byaddr, count, sizeof (uint_t), byaddr_cmp); qsort(symtab->sym_byname, count, sizeof (uint_t), byname_cmp); sort_strs = NULL; sort_syms = NULL; (void) mutex_unlock(&sort_mtx); free(syms); } /* * Build the symbol table for the given mapped file. */ void Pbuild_file_symtab(struct ps_prochandle *P, file_info_t *fptr) { char objectfile[PATH_MAX]; uint_t i; GElf_Ehdr ehdr; GElf_Sym s; Elf_Data *shdata; Elf_Scn *scn; Elf *elf; struct { GElf_Shdr c_shdr; Elf_Data *c_data; const char *c_name; } *cp, *cache = NULL, *dyn = NULL, *plt = NULL, *ctf = NULL; if (fptr->file_init) return; /* We've already processed this file */ /* * Mark the file_info struct as having the symbol table initialized * even if we fail below. We tried once; we don't try again. */ fptr->file_init = 1; if (elf_version(EV_CURRENT) == EV_NONE) { dprintf("libproc ELF version is more recent than libelf\n"); return; } if (P->state == PS_DEAD || P->state == PS_IDLE) { /* * If we're a not live, we can't open files from the /proc * object directory; we have only the mapping and file names * to guide us. We prefer the file_lname, but need to handle * the case of it being NULL in order to bootstrap: we first * come here during rd_new() when the only information we have * is interpreter name associated with the AT_BASE mapping. */ (void) snprintf(objectfile, sizeof (objectfile), "%s", fptr->file_lname ? fptr->file_lname : fptr->file_pname); } else { (void) snprintf(objectfile, sizeof (objectfile), "/proc/%d/object/%s", (int)P->pid, fptr->file_pname); } /* * Open the object file, create the elf file, and then get the elf * header and .shstrtab data buffer so we can process sections by * name. If anything goes wrong try to fake up an elf file from * the in-core elf image. */ if ((fptr->file_fd = open(objectfile, O_RDONLY)) < 0) { dprintf("Pbuild_file_symtab: failed to open %s: %s\n", objectfile, strerror(errno)); if ((elf = fake_elf(P, fptr)) == NULL || elf_kind(elf) != ELF_K_ELF || gelf_getehdr(elf, &ehdr) == NULL || (scn = elf_getscn(elf, ehdr.e_shstrndx)) == NULL || (shdata = elf_getdata(scn, NULL)) == NULL) { dprintf("failed to fake up ELF file\n"); return; } } else if ((elf = elf_begin(fptr->file_fd, ELF_C_READ, NULL)) == NULL || elf_kind(elf) != ELF_K_ELF || gelf_getehdr(elf, &ehdr) == NULL || (scn = elf_getscn(elf, ehdr.e_shstrndx)) == NULL || (shdata = elf_getdata(scn, NULL)) == NULL) { dprintf("failed to process ELF file %s: %s\n", objectfile, elf_errmsg(elf_errno())); if ((elf = fake_elf(P, fptr)) == NULL || elf_kind(elf) != ELF_K_ELF || gelf_getehdr(elf, &ehdr) == NULL || (scn = elf_getscn(elf, ehdr.e_shstrndx)) == NULL || (shdata = elf_getdata(scn, NULL)) == NULL) { dprintf("failed to fake up ELF file\n"); goto bad; } } else if (file_differs(P, elf, fptr)) { Elf *newelf; /* * Before we get too excited about this elf file, we'll check * its checksum value against the value we have in memory. If * they don't agree, we try to fake up a new elf file and * proceed with that instead. */ dprintf("ELF file %s (%lx) doesn't match in-core image\n", fptr->file_pname, (ulong_t)fptr->file_map->map_pmap.pr_vaddr); if ((newelf = fake_elf(P, fptr)) == NULL || elf_kind(newelf) != ELF_K_ELF || gelf_getehdr(newelf, &ehdr) == NULL || (scn = elf_getscn(newelf, ehdr.e_shstrndx)) == NULL || (shdata = elf_getdata(scn, NULL)) == NULL) { dprintf("failed to fake up ELF file\n"); } else { (void) elf_end(elf); elf = newelf; dprintf("switched to faked up ELF file\n"); } } if ((cache = malloc(ehdr.e_shnum * sizeof (*cache))) == NULL) { dprintf("failed to malloc section cache for %s\n", objectfile); goto bad; } dprintf("processing ELF file %s\n", objectfile); fptr->file_class = ehdr.e_ident[EI_CLASS]; fptr->file_etype = ehdr.e_type; fptr->file_elf = elf; /* * Iterate through each section, caching its section header, data * pointer, and name. We use this for handling sh_link values below. */ for (cp = cache + 1, scn = NULL; scn = elf_nextscn(elf, scn); cp++) { if (gelf_getshdr(scn, &cp->c_shdr) == NULL) goto bad; /* Failed to get section header */ if ((cp->c_data = elf_getdata(scn, NULL)) == NULL) goto bad; /* Failed to get section data */ if (cp->c_shdr.sh_name >= shdata->d_size) goto bad; /* Corrupt section name */ cp->c_name = (const char *)shdata->d_buf + cp->c_shdr.sh_name; } /* * Now iterate through the section cache in order to locate info * for the .symtab, .dynsym, .dynamic, .plt, and .SUNW_ctf sections: */ for (i = 1, cp = cache + 1; i < ehdr.e_shnum; i++, cp++) { GElf_Shdr *shp = &cp->c_shdr; if (shp->sh_type == SHT_SYMTAB || shp->sh_type == SHT_DYNSYM) { sym_tbl_t *symp = shp->sh_type == SHT_SYMTAB ? &fptr->file_symtab : &fptr->file_dynsym; /* * It's possible that the we already got the symbol * table from the core file itself. Either the file * differs in which case our faked up elf file will * only contain the dynsym (not the symtab) or the * file matches in which case we'll just be replacing * the symbol table we pulled out of the core file * with an equivalent one. In either case, this * check isn't essential, but it's a good idea. */ if (symp->sym_data == NULL) { symp->sym_data = cp->c_data; symp->sym_symn = shp->sh_size / shp->sh_entsize; symp->sym_strs = cache[shp->sh_link].c_data->d_buf; symp->sym_strsz = cache[shp->sh_link].c_data->d_size; symp->sym_hdr = cp->c_shdr; symp->sym_strhdr = cache[shp->sh_link].c_shdr; } } else if (shp->sh_type == SHT_DYNAMIC) { dyn = cp; } else if (strcmp(cp->c_name, ".plt") == 0) { plt = cp; } else if (strcmp(cp->c_name, ".SUNW_ctf") == 0) { /* * Skip over bogus CTF sections so they don't come back * to haunt us later. */ if (shp->sh_link == 0 || shp->sh_link > ehdr.e_shnum || (cache[shp->sh_link].c_shdr.sh_type != SHT_DYNSYM && cache[shp->sh_link].c_shdr.sh_type != SHT_SYMTAB)) { dprintf("Bad sh_link %d for " "CTF\n", shp->sh_link); continue; } ctf = cp; } } /* * At this point, we've found all the symbol tables we're ever going * to find: the ones in the loop above and possibly the symtab that * was included in the core file. Before we perform any lookups, we * create sorted versions to optimize for lookups. */ optimize_symtab(&fptr->file_symtab); optimize_symtab(&fptr->file_dynsym); /* * Fill in the base address of the text mapping for shared libraries. * This allows us to translate symbols before librtld_db is ready. */ if (fptr->file_etype == ET_DYN) { fptr->file_dyn_base = fptr->file_map->map_pmap.pr_vaddr - fptr->file_map->map_pmap.pr_offset; dprintf("setting file_dyn_base for %s to %p\n", objectfile, (void *)fptr->file_dyn_base); } /* * Record the CTF section information in the file info structure. */ if (ctf != NULL) { fptr->file_ctf_off = ctf->c_shdr.sh_offset; fptr->file_ctf_size = ctf->c_shdr.sh_size; if (ctf->c_shdr.sh_link != 0 && cache[ctf->c_shdr.sh_link].c_shdr.sh_type == SHT_DYNSYM) fptr->file_ctf_dyn = 1; } if (fptr->file_lo == NULL) goto done; /* Nothing else to do if no load object info */ /* * If the object is a shared library and we have a different rl_base * value, reset file_dyn_base according to librtld_db's information. */ if (fptr->file_etype == ET_DYN && fptr->file_lo->rl_base != fptr->file_dyn_base) { dprintf("resetting file_dyn_base for %s to %p\n", objectfile, (void *)fptr->file_lo->rl_base); fptr->file_dyn_base = fptr->file_lo->rl_base; } /* * Fill in the PLT information for this file if a PLT symbol is found. */ if (sym_by_name(&fptr->file_dynsym, "_PROCEDURE_LINKAGE_TABLE_", &s, NULL) != NULL) { fptr->file_plt_base = s.st_value + fptr->file_dyn_base; fptr->file_plt_size = (plt != NULL) ? plt->c_shdr.sh_size : 0; /* * Bring the load object up to date; it is the only way the * user has to access the PLT data. The PLT information in the * rd_loadobj_t is not set in the call to map_iter() (the * callback for rd_loadobj_iter) where we set file_lo. */ fptr->file_lo->rl_plt_base = fptr->file_plt_base; fptr->file_lo->rl_plt_size = fptr->file_plt_size; dprintf("PLT found at %p, size = %lu\n", (void *)fptr->file_plt_base, (ulong_t)fptr->file_plt_size); } /* * Fill in the PLT information. */ if (dyn != NULL) { uintptr_t dynaddr = dyn->c_shdr.sh_addr + fptr->file_dyn_base; size_t ndyn = dyn->c_shdr.sh_size / dyn->c_shdr.sh_entsize; GElf_Dyn d; for (i = 0; i < ndyn; i++) { if (gelf_getdyn(dyn->c_data, i, &d) != NULL && d.d_tag == DT_JMPREL) { fptr->file_jmp_rel = d.d_un.d_ptr + fptr->file_dyn_base; break; } } dprintf("_DYNAMIC found at %p, %lu entries, DT_JMPREL = %p\n", (void *)dynaddr, (ulong_t)ndyn, (void *)fptr->file_jmp_rel); } done: free(cache); return; bad: if (cache != NULL) free(cache); (void) elf_end(elf); fptr->file_elf = NULL; if (fptr->file_elfmem != NULL) { free(fptr->file_elfmem); fptr->file_elfmem = NULL; } (void) close(fptr->file_fd); fptr->file_fd = -1; } /* * Given a process virtual address, return the map_info_t containing it. * If none found, return NULL. */ map_info_t * Paddr2mptr(struct ps_prochandle *P, uintptr_t addr) { int lo = 0; int hi = P->map_count - 1; int mid; map_info_t *mp; while (lo <= hi) { mid = (lo + hi) / 2; mp = &P->mappings[mid]; /* check that addr is in [vaddr, vaddr + size) */ if ((addr - mp->map_pmap.pr_vaddr) < mp->map_pmap.pr_size) return (mp); if (addr < mp->map_pmap.pr_vaddr) hi = mid - 1; else lo = mid + 1; } return (NULL); } /* * Return the map_info_t for the executable file. * If not found, return NULL. */ static map_info_t * exec_map(struct ps_prochandle *P) { uint_t i; map_info_t *mptr; map_info_t *mold = NULL; file_info_t *fptr; uintptr_t base; for (i = 0, mptr = P->mappings; i < P->map_count; i++, mptr++) { if (mptr->map_pmap.pr_mapname[0] == '\0') continue; if (strcmp(mptr->map_pmap.pr_mapname, "a.out") == 0) { if ((fptr = mptr->map_file) != NULL && fptr->file_lo != NULL) { base = fptr->file_lo->rl_base; if (base >= mptr->map_pmap.pr_vaddr && base < mptr->map_pmap.pr_vaddr + mptr->map_pmap.pr_size) /* text space */ return (mptr); mold = mptr; /* must be the data */ continue; } /* This is a poor way to test for text space */ if (!(mptr->map_pmap.pr_mflags & MA_EXEC) || (mptr->map_pmap.pr_mflags & MA_WRITE)) { mold = mptr; continue; } return (mptr); } } return (mold); } /* * Given a shared object name, return the map_info_t for it. If no matching * object is found, return NULL. Normally, the link maps contain the full * object pathname, e.g. /usr/lib/libc.so.1. We allow the object name to * take one of the following forms: * * 1. An exact match (i.e. a full pathname): "/usr/lib/libc.so.1" * 2. An exact basename match: "libc.so.1" * 3. An initial basename match up to a '.' suffix: "libc.so" or "libc" * 4. The literal string "a.out" is an alias for the executable mapping * * The third case is a convenience for callers and may not be necessary. * * As the exact same object name may be loaded on different link maps (see * dlmopen(3DL)), we also allow the caller to resolve the object name by * specifying a particular link map id. If lmid is PR_LMID_EVERY, the * first matching name will be returned, regardless of the link map id. */ static map_info_t * object_to_map(struct ps_prochandle *P, Lmid_t lmid, const char *objname) { map_info_t *mp; file_info_t *fp; size_t objlen; uint_t i; /* * First pass: look for exact matches of the entire pathname or * basename (cases 1 and 2 above): */ for (i = 0, mp = P->mappings; i < P->map_count; i++, mp++) { if (mp->map_pmap.pr_mapname[0] == '\0' || (fp = mp->map_file) == NULL || fp->file_lname == NULL) continue; if (lmid != PR_LMID_EVERY && (fp->file_lo == NULL || lmid != fp->file_lo->rl_lmident)) continue; /* * If we match, return the primary text mapping; otherwise * just return the mapping we matched. */ if (strcmp(fp->file_lname, objname) == 0 || strcmp(fp->file_lbase, objname) == 0) return (fp->file_map ? fp->file_map : mp); } objlen = strlen(objname); /* * Second pass: look for partial matches (case 3 above): */ for (i = 0, mp = P->mappings; i < P->map_count; i++, mp++) { if (mp->map_pmap.pr_mapname[0] == '\0' || (fp = mp->map_file) == NULL || fp->file_lname == NULL) continue; if (lmid != PR_LMID_EVERY && (fp->file_lo == NULL || lmid != fp->file_lo->rl_lmident)) continue; /* * If we match, return the primary text mapping; otherwise * just return the mapping we matched. */ if (strncmp(fp->file_lbase, objname, objlen) == 0 && fp->file_lbase[objlen] == '.') return (fp->file_map ? fp->file_map : mp); } /* * One last check: we allow "a.out" to always alias the executable, * assuming this name was not in use for something else. */ if ((lmid == PR_LMID_EVERY || lmid == LM_ID_BASE) && (strcmp(objname, "a.out") == 0)) return (P->map_exec); return (NULL); } static map_info_t * object_name_to_map(struct ps_prochandle *P, Lmid_t lmid, const char *name) { map_info_t *mptr; if (!P->info_valid) Pupdate_maps(P); if (P->map_exec == NULL && ((mptr = Paddr2mptr(P, Pgetauxval(P, AT_ENTRY))) != NULL || (mptr = exec_map(P)) != NULL)) P->map_exec = mptr; if (P->map_ldso == NULL && (mptr = Paddr2mptr(P, Pgetauxval(P, AT_BASE))) != NULL) P->map_ldso = mptr; if (name == PR_OBJ_EXEC) mptr = P->map_exec; else if (name == PR_OBJ_LDSO) mptr = P->map_ldso; else if (Prd_agent(P) != NULL || P->state == PS_IDLE) mptr = object_to_map(P, lmid, name); else mptr = NULL; return (mptr); } /* * When two symbols are found by address, decide which one is to be preferred. */ static GElf_Sym * sym_prefer(GElf_Sym *sym1, char *name1, GElf_Sym *sym2, char *name2) { /* * Prefer the non-NULL symbol. */ if (sym1 == NULL) return (sym2); if (sym2 == NULL) return (sym1); /* * Defer to the sort ordering... */ return (byaddr_cmp_common(sym1, name1, sym2, name2) <= 0 ? sym1 : sym2); } /* * Look up a symbol by address in the specified symbol table. * Adjustment to 'addr' must already have been made for the * offset of the symbol if this is a dynamic library symbol table. */ static GElf_Sym * sym_by_addr(sym_tbl_t *symtab, GElf_Addr addr, GElf_Sym *symp, uint_t *idp) { Elf_Data *data = symtab->sym_data; GElf_Sym sym, osym; uint_t i, oid, *byaddr = symtab->sym_byaddr; int min, max, mid, omid, found = 0; if (data == NULL) return (NULL); min = 0; max = symtab->sym_count - 1; osym.st_value = 0; /* * We can't return when we've found a match, we have to continue * searching for the closest matching symbol. */ while (min <= max) { mid = (max + min) / 2; i = byaddr[mid]; (void) gelf_getsym(data, i, &sym); if (addr >= sym.st_value && addr < sym.st_value + sym.st_size && (!found || sym.st_value > osym.st_value)) { osym = sym; omid = mid; oid = i; found = 1; } if (addr < sym.st_value) max = mid - 1; else min = mid + 1; } if (!found) return (NULL); /* * There may be many symbols with identical values so we walk * backward in the byaddr table to find the best match. */ do { sym = osym; i = oid; if (omid == 0) break; oid = byaddr[--omid]; (void) gelf_getsym(data, oid, &osym); } while (addr >= osym.st_value && addr < sym.st_value + osym.st_size && osym.st_value == sym.st_value); *symp = sym; if (idp != NULL) *idp = i; return (symp); } /* * Look up a symbol by name in the specified symbol table. */ static GElf_Sym * sym_by_name(sym_tbl_t *symtab, const char *name, GElf_Sym *symp, uint_t *idp) { Elf_Data *data = symtab->sym_data; char *strs = symtab->sym_strs; uint_t i, *byname = symtab->sym_byname; int min, mid, max, cmp; if (data == NULL || strs == NULL) return (NULL); min = 0; max = symtab->sym_count - 1; while (min <= max) { mid = (max + min) / 2; i = byname[mid]; (void) gelf_getsym(data, i, symp); if ((cmp = strcmp(name, strs + symp->st_name)) == 0) { if (idp != NULL) *idp = i; return (symp); } if (cmp < 0) max = mid - 1; else min = mid + 1; } return (NULL); } /* * Search the process symbol tables looking for a symbol whose * value to value+size contain the address specified by addr. * Return values are: * sym_name_buffer containing the symbol name * GElf_Sym symbol table entry * prsyminfo_t ancillary symbol information * Returns 0 on success, -1 on failure. */ int Pxlookup_by_addr( struct ps_prochandle *P, uintptr_t addr, /* process address being sought */ char *sym_name_buffer, /* buffer for the symbol name */ size_t bufsize, /* size of sym_name_buffer */ GElf_Sym *symbolp, /* returned symbol table entry */ prsyminfo_t *sip) /* returned symbol info */ { GElf_Sym *symp; char *name; GElf_Sym sym1, *sym1p = NULL; GElf_Sym sym2, *sym2p = NULL; char *name1 = NULL; char *name2 = NULL; uint_t i1; uint_t i2; map_info_t *mptr; file_info_t *fptr; (void) Prd_agent(P); if ((mptr = Paddr2mptr(P, addr)) == NULL || /* no such address */ (fptr = build_map_symtab(P, mptr)) == NULL || /* no mapped file */ fptr->file_elf == NULL) /* not an ELF file */ return (-1); /* * Adjust the address by the load object base address in * case the address turns out to be in a shared library. */ addr -= fptr->file_dyn_base; /* * Search both symbol tables, symtab first, then dynsym. */ if ((sym1p = sym_by_addr(&fptr->file_symtab, addr, &sym1, &i1)) != NULL) name1 = fptr->file_symtab.sym_strs + sym1.st_name; if ((sym2p = sym_by_addr(&fptr->file_dynsym, addr, &sym2, &i2)) != NULL) name2 = fptr->file_dynsym.sym_strs + sym2.st_name; if ((symp = sym_prefer(sym1p, name1, sym2p, name2)) == NULL) return (-1); name = (symp == sym1p) ? name1 : name2; if (bufsize > 0) { (void) strncpy(sym_name_buffer, name, bufsize); sym_name_buffer[bufsize - 1] = '\0'; } *symbolp = *symp; if (sip != NULL) { sip->prs_name = bufsize == 0 ? NULL : sym_name_buffer; sip->prs_object = fptr->file_lbase; sip->prs_id = (symp == sym1p) ? i1 : i2; sip->prs_table = (symp == sym1p) ? PR_SYMTAB : PR_DYNSYM; sip->prs_lmid = (fptr->file_lo == NULL) ? LM_ID_BASE : fptr->file_lo->rl_lmident; } if (GELF_ST_TYPE(symbolp->st_info) != STT_TLS) symbolp->st_value += fptr->file_dyn_base; return (0); } int Plookup_by_addr(struct ps_prochandle *P, uintptr_t addr, char *buf, size_t size, GElf_Sym *symp) { return (Pxlookup_by_addr(P, addr, buf, size, symp, NULL)); } /* * Search the process symbol tables looking for a symbol whose name matches the * specified name and whose object and link map optionally match the specified * parameters. On success, the function returns 0 and fills in the GElf_Sym * symbol table entry. On failure, -1 is returned. */ int Pxlookup_by_name( struct ps_prochandle *P, Lmid_t lmid, /* link map to match, or -1 for any */ const char *oname, /* load object name */ const char *sname, /* symbol name */ GElf_Sym *symp, /* returned symbol table entry */ prsyminfo_t *sip) /* returned symbol info */ { map_info_t *mptr; file_info_t *fptr; int cnt; GElf_Sym sym; prsyminfo_t si; int rv = -1; uint_t id; if (oname == PR_OBJ_EVERY) { /* create all the file_info_t's for all the mappings */ (void) Prd_agent(P); cnt = P->num_files; fptr = list_next(&P->file_head); } else { cnt = 1; if ((mptr = object_name_to_map(P, lmid, oname)) == NULL || (fptr = build_map_symtab(P, mptr)) == NULL) return (-1); } /* * Iterate through the loaded object files and look for the symbol * name in the .symtab and .dynsym of each. If we encounter a match * with SHN_UNDEF, keep looking in hopes of finding a better match. * This means that a name such as "puts" will match the puts function * in libc instead of matching the puts PLT entry in the a.out file. */ for (; cnt > 0; cnt--, fptr = list_next(fptr)) { Pbuild_file_symtab(P, fptr); if (fptr->file_elf == NULL) continue; if (lmid != PR_LMID_EVERY && fptr->file_lo != NULL && lmid != fptr->file_lo->rl_lmident) continue; if (fptr->file_symtab.sym_data != NULL && sym_by_name(&fptr->file_symtab, sname, symp, &id)) { if (sip != NULL) { sip->prs_id = id; sip->prs_table = PR_SYMTAB; sip->prs_object = oname; sip->prs_name = sname; sip->prs_lmid = fptr->file_lo == NULL ? LM_ID_BASE : fptr->file_lo->rl_lmident; } } else if (fptr->file_dynsym.sym_data != NULL && sym_by_name(&fptr->file_dynsym, sname, symp, &id)) { if (sip != NULL) { sip->prs_id = id; sip->prs_table = PR_DYNSYM; sip->prs_object = oname; sip->prs_name = sname; sip->prs_lmid = fptr->file_lo == NULL ? LM_ID_BASE : fptr->file_lo->rl_lmident; } } else { continue; } if (GELF_ST_TYPE(symp->st_info) != STT_TLS) symp->st_value += fptr->file_dyn_base; if (symp->st_shndx != SHN_UNDEF) return (0); if (rv != 0) { if (sip != NULL) si = *sip; sym = *symp; rv = 0; } } if (rv == 0) { if (sip != NULL) *sip = si; *symp = sym; } return (rv); } /* * Search the process symbol tables looking for a symbol whose name matches the * specified name, but without any restriction on the link map id. */ int Plookup_by_name(struct ps_prochandle *P, const char *object, const char *symbol, GElf_Sym *symp) { return (Pxlookup_by_name(P, PR_LMID_EVERY, object, symbol, symp, NULL)); } /* * Iterate over the process's address space mappings. */ int Pmapping_iter(struct ps_prochandle *P, proc_map_f *func, void *cd) { map_info_t *mptr; file_info_t *fptr; char *object_name; int rc = 0; int i; /* create all the file_info_t's for all the mappings */ (void) Prd_agent(P); for (i = 0, mptr = P->mappings; i < P->map_count; i++, mptr++) { if ((fptr = mptr->map_file) == NULL) object_name = NULL; else object_name = fptr->file_lname; if ((rc = func(cd, &mptr->map_pmap, object_name)) != 0) return (rc); } return (0); } /* * Iterate over the process's mapped objects. */ int Pobject_iter(struct ps_prochandle *P, proc_map_f *func, void *cd) { map_info_t *mptr; file_info_t *fptr; uint_t cnt; int rc = 0; (void) Prd_agent(P); /* create file_info_t's for all the mappings */ Pupdate_maps(P); for (cnt = P->num_files, fptr = list_next(&P->file_head); cnt; cnt--, fptr = list_next(fptr)) { const char *lname = fptr->file_lname ? fptr->file_lname : ""; if ((mptr = fptr->file_map) == NULL) continue; if ((rc = func(cd, &mptr->map_pmap, lname)) != 0) return (rc); } return (0); } /* * Given a virtual address, return the name of the underlying * mapped object (file), as provided by the dynamic linker. * Return NULL on failure (no underlying shared library). */ char * Pobjname(struct ps_prochandle *P, uintptr_t addr, char *buffer, size_t bufsize) { map_info_t *mptr; file_info_t *fptr; /* create all the file_info_t's for all the mappings */ (void) Prd_agent(P); if ((mptr = Paddr2mptr(P, addr)) != NULL && (fptr = mptr->map_file) != NULL && fptr->file_lname != NULL) { (void) strncpy(buffer, fptr->file_lname, bufsize); if (strlen(fptr->file_lname) >= bufsize) buffer[bufsize-1] = '\0'; return (buffer); } return (NULL); } /* * Given a virtual address, return the link map id of the underlying mapped * object (file), as provided by the dynamic linker. Return -1 on failure. */ int Plmid(struct ps_prochandle *P, uintptr_t addr, Lmid_t *lmidp) { map_info_t *mptr; file_info_t *fptr; /* create all the file_info_t's for all the mappings */ (void) Prd_agent(P); if ((mptr = Paddr2mptr(P, addr)) != NULL && (fptr = mptr->map_file) != NULL && fptr->file_lo != NULL) { *lmidp = fptr->file_lo->rl_lmident; return (0); } return (-1); } /* * Given an object name and optional lmid, iterate over the object's symbols. * If which == PR_SYMTAB, search the normal symbol table. * If which == PR_DYNSYM, search the dynamic symbol table. */ static int Psymbol_iter_com(struct ps_prochandle *P, Lmid_t lmid, const char *object_name, int which, int mask, pr_order_t order, proc_xsym_f *func, void *cd) { GElf_Sym sym; map_info_t *mptr; file_info_t *fptr; sym_tbl_t *symtab; Elf_Data *data; size_t symn; const char *strs; size_t strsz; prsyminfo_t si; int rv; uint_t *map, i, count, ndx; if ((mptr = object_name_to_map(P, lmid, object_name)) == NULL) return (-1); if ((fptr = build_map_symtab(P, mptr)) == NULL || /* no mapped file */ fptr->file_elf == NULL) /* not an ELF file */ return (-1); /* * Search the specified symbol table. */ switch (which) { case PR_SYMTAB: symtab = &fptr->file_symtab; si.prs_table = PR_SYMTAB; break; case PR_DYNSYM: symtab = &fptr->file_dynsym; si.prs_table = PR_DYNSYM; break; default: return (-1); } si.prs_object = object_name; si.prs_lmid = fptr->file_lo == NULL ? LM_ID_BASE : fptr->file_lo->rl_lmident; data = symtab->sym_data; symn = symtab->sym_symn; strs = symtab->sym_strs; strsz = symtab->sym_strsz; if (data == NULL || strs == NULL) return (-1); switch (order) { case PRO_NATURAL: map = NULL; count = symn; break; case PRO_BYNAME: map = symtab->sym_byname; count = symtab->sym_count; break; case PRO_BYADDR: map = symtab->sym_byaddr; count = symtab->sym_count; break; default: return (-1); } rv = 0; for (i = 0; i < count; i++) { ndx = map == NULL ? i : map[i]; if (gelf_getsym(data, ndx, &sym) != NULL) { uint_t s_bind, s_type, type; if (sym.st_name >= strsz) /* invalid st_name */ continue; s_bind = GELF_ST_BIND(sym.st_info); s_type = GELF_ST_TYPE(sym.st_info); /* * In case you haven't already guessed, this relies on * the bitmask used in for encoding symbol * type and binding matching the order of STB and STT * constants in . ELF can't change without * breaking binary compatibility, so I think this is * reasonably fair game. */ if (s_bind < STB_NUM && s_type < STT_NUM) { type = (1 << (s_type + 8)) | (1 << s_bind); if ((type & ~mask) != 0) continue; } else continue; /* Invalid type or binding */ if (GELF_ST_TYPE(sym.st_info) != STT_TLS) sym.st_value += fptr->file_dyn_base; si.prs_name = strs + sym.st_name; si.prs_id = ndx; if ((rv = func(cd, &sym, strs + sym.st_name, &si)) != 0) break; } } return (rv); } int Pxsymbol_iter(struct ps_prochandle *P, Lmid_t lmid, const char *object_name, int which, int mask, proc_xsym_f *func, void *cd) { return (Psymbol_iter_com(P, lmid, object_name, which, mask, PRO_NATURAL, func, cd)); } int Psymbol_iter_by_lmid(struct ps_prochandle *P, Lmid_t lmid, const char *object_name, int which, int mask, proc_sym_f *func, void *cd) { return (Psymbol_iter_com(P, lmid, object_name, which, mask, PRO_NATURAL, (proc_xsym_f *)func, cd)); } int Psymbol_iter(struct ps_prochandle *P, const char *object_name, int which, int mask, proc_sym_f *func, void *cd) { return (Psymbol_iter_com(P, PR_LMID_EVERY, object_name, which, mask, PRO_NATURAL, (proc_xsym_f *)func, cd)); } int Psymbol_iter_by_addr(struct ps_prochandle *P, const char *object_name, int which, int mask, proc_sym_f *func, void *cd) { return (Psymbol_iter_com(P, PR_LMID_EVERY, object_name, which, mask, PRO_BYADDR, (proc_xsym_f *)func, cd)); } int Psymbol_iter_by_name(struct ps_prochandle *P, const char *object_name, int which, int mask, proc_sym_f *func, void *cd) { return (Psymbol_iter_com(P, PR_LMID_EVERY, object_name, which, mask, PRO_BYNAME, (proc_xsym_f *)func, cd)); } /* * Get the platform string from the core file if we have it; * just perform the system call for the caller if this is a live process. */ char * Pplatform(struct ps_prochandle *P, char *s, size_t n) { if (P->state == PS_IDLE) { errno = ENODATA; return (NULL); } if (P->state == PS_DEAD) { if (P->core->core_platform == NULL) { errno = ENODATA; return (NULL); } (void) strncpy(s, P->core->core_platform, n - 1); s[n - 1] = '\0'; } else if (sysinfo(SI_PLATFORM, s, n) == -1) return (NULL); return (s); } /* * Get the uname(2) information from the core file if we have it; * just perform the system call for the caller if this is a live process. */ int Puname(struct ps_prochandle *P, struct utsname *u) { if (P->state == PS_IDLE) { errno = ENODATA; return (-1); } if (P->state == PS_DEAD) { if (P->core->core_uts == NULL) { errno = ENODATA; return (-1); } (void) memcpy(u, P->core->core_uts, sizeof (struct utsname)); return (0); } return (uname(u)); } /* * Get the zone name from the core file if we have it; look up the * name based on the zone id if this is a live process. */ char * Pzonename(struct ps_prochandle *P, char *s, size_t n) { if (P->state == PS_IDLE) { errno = ENODATA; return (NULL); } if (P->state == PS_DEAD) { if (P->core->core_zonename == NULL) { errno = ENODATA; return (NULL); } (void) strlcpy(s, P->core->core_zonename, n); } else { if (getzonenamebyid(P->status.pr_zoneid, s, n) < 0) return (NULL); s[n - 1] = '\0'; } return (s); } /* * Called from Pcreate(), Pgrab(), and Pfgrab_core() to initialize * the symbol table heads in the new ps_prochandle. */ void Pinitsym(struct ps_prochandle *P) { P->num_files = 0; list_link(&P->file_head, NULL); } /* * Called from Prelease() to destroy the symbol tables. * Must be called by the client after an exec() in the victim process. */ void Preset_maps(struct ps_prochandle *P) { int i; if (P->rap != NULL) { rd_delete(P->rap); P->rap = NULL; } if (P->execname != NULL) { free(P->execname); P->execname = NULL; } if (P->auxv != NULL) { free(P->auxv); P->auxv = NULL; P->nauxv = 0; } for (i = 0; i < P->map_count; i++) map_info_free(P, &P->mappings[i]); if (P->mappings != NULL) { free(P->mappings); P->mappings = NULL; } P->map_count = P->map_alloc = 0; P->info_valid = 0; } typedef struct getenv_data { char *buf; size_t bufsize; const char *search; size_t searchlen; } getenv_data_t; /*ARGSUSED*/ static int getenv_func(void *data, struct ps_prochandle *P, uintptr_t addr, const char *nameval) { getenv_data_t *d = data; size_t len; if (nameval == NULL) return (0); if (d->searchlen < strlen(nameval) && strncmp(nameval, d->search, d->searchlen) == 0 && nameval[d->searchlen] == '=') { len = MIN(strlen(nameval), d->bufsize - 1); (void) strncpy(d->buf, nameval, len); d->buf[len] = '\0'; return (1); } return (0); } char * Pgetenv(struct ps_prochandle *P, const char *name, char *buf, size_t buflen) { getenv_data_t d; d.buf = buf; d.bufsize = buflen; d.search = name; d.searchlen = strlen(name); if (Penv_iter(P, getenv_func, &d) == 1) { char *equals = strchr(d.buf, '='); if (equals != NULL) { (void) memmove(d.buf, equals + 1, d.buf + buflen - equals - 1); d.buf[d.buf + buflen - equals] = '\0'; return (buf); } } return (NULL); } /* number of argument or environment pointers to read all at once */ #define NARG 100 int Penv_iter(struct ps_prochandle *P, proc_env_f *func, void *data) { const psinfo_t *psp; uintptr_t envpoff; GElf_Sym sym; int ret; char *buf, *nameval; size_t buflen; int nenv = NARG; long envp[NARG]; /* * Attempt to find the "_environ" variable in the process. * Failing that, use the original value provided by Ppsinfo(). */ if ((psp = Ppsinfo(P)) == NULL) return (-1); envpoff = psp->pr_envp; /* Default if no _environ found */ if (Plookup_by_name(P, PR_OBJ_EXEC, "_environ", &sym) == 0) { if (P->status.pr_dmodel == PR_MODEL_NATIVE) { if (Pread(P, &envpoff, sizeof (envpoff), sym.st_value) != sizeof (envpoff)) envpoff = psp->pr_envp; } else if (P->status.pr_dmodel == PR_MODEL_ILP32) { uint32_t envpoff32; if (Pread(P, &envpoff32, sizeof (envpoff32), sym.st_value) != sizeof (envpoff32)) envpoff = psp->pr_envp; else envpoff = envpoff32; } } buflen = 128; buf = malloc(buflen); ret = 0; for (;;) { uintptr_t envoff; if (nenv == NARG) { (void) memset(envp, 0, sizeof (envp)); if (P->status.pr_dmodel == PR_MODEL_NATIVE) { if (Pread(P, envp, sizeof (envp), envpoff) <= 0) { ret = -1; break; } } else if (P->status.pr_dmodel == PR_MODEL_ILP32) { uint32_t e32[NARG]; int i; (void) memset(e32, 0, sizeof (e32)); if (Pread(P, e32, sizeof (e32), envpoff) <= 0) { ret = -1; break; } for (i = 0; i < NARG; i++) envp[i] = e32[i]; } nenv = 0; } if ((envoff = envp[nenv++]) == NULL) break; /* * Attempt to read the string from the process. */ again: ret = Pread_string(P, buf, buflen, envoff); if (ret <= 0) { nameval = NULL; } else if (ret == buflen - 1) { free(buf); /* * Bail if we have a corrupted environment */ if (buflen >= ARG_MAX) return (-1); buflen *= 2; buf = malloc(buflen); goto again; } else { nameval = buf; } if ((ret = func(data, P, envoff, nameval)) != 0) break; envpoff += (P->status.pr_dmodel == PR_MODEL_LP64)? 8 : 4; } free(buf); return (ret); }