/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (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 (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. */ #include #if defined(sun) #include #include #include #include #include #include #else #include #include #include #endif #include #if defined(sun) #include #endif #include #include #include #include #include #include #include #if !defined(sun) #include #endif #include #include #include static const char *dt_module_strtab; /* active strtab for qsort callbacks */ static void dt_module_symhash_insert(dt_module_t *dmp, const char *name, uint_t id) { dt_sym_t *dsp = &dmp->dm_symchains[dmp->dm_symfree]; uint_t h; assert(dmp->dm_symfree < dmp->dm_nsymelems + 1); dsp->ds_symid = id; h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets; dsp->ds_next = dmp->dm_symbuckets[h]; dmp->dm_symbuckets[h] = dmp->dm_symfree++; } static uint_t dt_module_syminit32(dt_module_t *dmp) { #if STT_NUM != (STT_TLS + 1) #error "STT_NUM has grown. update dt_module_syminit32()" #endif Elf32_Sym *sym = dmp->dm_symtab.cts_data; const char *base = dmp->dm_strtab.cts_data; size_t ss_size = dmp->dm_strtab.cts_size; uint_t i, n = dmp->dm_nsymelems; uint_t asrsv = 0; #if defined(__FreeBSD__) GElf_Ehdr ehdr; int is_elf_obj; gelf_getehdr(dmp->dm_elf, &ehdr); is_elf_obj = (ehdr.e_type == ET_REL); #endif for (i = 0; i < n; i++, sym++) { const char *name = base + sym->st_name; uchar_t type = ELF32_ST_TYPE(sym->st_info); if (type >= STT_NUM || type == STT_SECTION) continue; /* skip sections and unknown types */ if (sym->st_name == 0 || sym->st_name >= ss_size) continue; /* skip null or invalid names */ if (sym->st_value != 0 && (ELF32_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) { asrsv++; /* reserve space in the address map */ #if defined(__FreeBSD__) sym->st_value += (Elf_Addr) dmp->dm_reloc_offset; if (is_elf_obj && sym->st_shndx != SHN_UNDEF && sym->st_shndx < ehdr.e_shnum) sym->st_value += dmp->dm_sec_offsets[sym->st_shndx]; #endif } dt_module_symhash_insert(dmp, name, i); } return (asrsv); } static uint_t dt_module_syminit64(dt_module_t *dmp) { #if STT_NUM != (STT_TLS + 1) #error "STT_NUM has grown. update dt_module_syminit64()" #endif Elf64_Sym *sym = dmp->dm_symtab.cts_data; const char *base = dmp->dm_strtab.cts_data; size_t ss_size = dmp->dm_strtab.cts_size; uint_t i, n = dmp->dm_nsymelems; uint_t asrsv = 0; #if defined(__FreeBSD__) GElf_Ehdr ehdr; int is_elf_obj; gelf_getehdr(dmp->dm_elf, &ehdr); is_elf_obj = (ehdr.e_type == ET_REL); #endif for (i = 0; i < n; i++, sym++) { const char *name = base + sym->st_name; uchar_t type = ELF64_ST_TYPE(sym->st_info); if (type >= STT_NUM || type == STT_SECTION) continue; /* skip sections and unknown types */ if (sym->st_name == 0 || sym->st_name >= ss_size) continue; /* skip null or invalid names */ if (sym->st_value != 0 && (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) { asrsv++; /* reserve space in the address map */ #if defined(__FreeBSD__) sym->st_value += (Elf_Addr) dmp->dm_reloc_offset; if (is_elf_obj && sym->st_shndx != SHN_UNDEF && sym->st_shndx < ehdr.e_shnum) sym->st_value += dmp->dm_sec_offsets[sym->st_shndx]; #endif } dt_module_symhash_insert(dmp, name, i); } return (asrsv); } /* * Sort comparison function for 32-bit symbol address-to-name lookups. We sort * symbols by value. If values are equal, we prefer the symbol that is * non-zero sized, typed, not weak, or lexically first, in that order. */ static int dt_module_symcomp32(const void *lp, const void *rp) { Elf32_Sym *lhs = *((Elf32_Sym **)lp); Elf32_Sym *rhs = *((Elf32_Sym **)rp); if (lhs->st_value != rhs->st_value) return (lhs->st_value > rhs->st_value ? 1 : -1); if ((lhs->st_size == 0) != (rhs->st_size == 0)) return (lhs->st_size == 0 ? 1 : -1); if ((ELF32_ST_TYPE(lhs->st_info) == STT_NOTYPE) != (ELF32_ST_TYPE(rhs->st_info) == STT_NOTYPE)) return (ELF32_ST_TYPE(lhs->st_info) == STT_NOTYPE ? 1 : -1); if ((ELF32_ST_BIND(lhs->st_info) == STB_WEAK) != (ELF32_ST_BIND(rhs->st_info) == STB_WEAK)) return (ELF32_ST_BIND(lhs->st_info) == STB_WEAK ? 1 : -1); return (strcmp(dt_module_strtab + lhs->st_name, dt_module_strtab + rhs->st_name)); } /* * Sort comparison function for 64-bit symbol address-to-name lookups. We sort * symbols by value. If values are equal, we prefer the symbol that is * non-zero sized, typed, not weak, or lexically first, in that order. */ static int dt_module_symcomp64(const void *lp, const void *rp) { Elf64_Sym *lhs = *((Elf64_Sym **)lp); Elf64_Sym *rhs = *((Elf64_Sym **)rp); if (lhs->st_value != rhs->st_value) return (lhs->st_value > rhs->st_value ? 1 : -1); if ((lhs->st_size == 0) != (rhs->st_size == 0)) return (lhs->st_size == 0 ? 1 : -1); if ((ELF64_ST_TYPE(lhs->st_info) == STT_NOTYPE) != (ELF64_ST_TYPE(rhs->st_info) == STT_NOTYPE)) return (ELF64_ST_TYPE(lhs->st_info) == STT_NOTYPE ? 1 : -1); if ((ELF64_ST_BIND(lhs->st_info) == STB_WEAK) != (ELF64_ST_BIND(rhs->st_info) == STB_WEAK)) return (ELF64_ST_BIND(lhs->st_info) == STB_WEAK ? 1 : -1); return (strcmp(dt_module_strtab + lhs->st_name, dt_module_strtab + rhs->st_name)); } static void dt_module_symsort32(dt_module_t *dmp) { Elf32_Sym *symtab = (Elf32_Sym *)dmp->dm_symtab.cts_data; Elf32_Sym **sympp = (Elf32_Sym **)dmp->dm_asmap; const dt_sym_t *dsp = dmp->dm_symchains + 1; uint_t i, n = dmp->dm_symfree; for (i = 1; i < n; i++, dsp++) { Elf32_Sym *sym = symtab + dsp->ds_symid; if (sym->st_value != 0 && (ELF32_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) *sympp++ = sym; } dmp->dm_aslen = (uint_t)(sympp - (Elf32_Sym **)dmp->dm_asmap); assert(dmp->dm_aslen <= dmp->dm_asrsv); dt_module_strtab = dmp->dm_strtab.cts_data; qsort(dmp->dm_asmap, dmp->dm_aslen, sizeof (Elf32_Sym *), dt_module_symcomp32); dt_module_strtab = NULL; } static void dt_module_symsort64(dt_module_t *dmp) { Elf64_Sym *symtab = (Elf64_Sym *)dmp->dm_symtab.cts_data; Elf64_Sym **sympp = (Elf64_Sym **)dmp->dm_asmap; const dt_sym_t *dsp = dmp->dm_symchains + 1; uint_t i, n = dmp->dm_symfree; for (i = 1; i < n; i++, dsp++) { Elf64_Sym *sym = symtab + dsp->ds_symid; if (sym->st_value != 0 && (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) *sympp++ = sym; } dmp->dm_aslen = (uint_t)(sympp - (Elf64_Sym **)dmp->dm_asmap); assert(dmp->dm_aslen <= dmp->dm_asrsv); dt_module_strtab = dmp->dm_strtab.cts_data; qsort(dmp->dm_asmap, dmp->dm_aslen, sizeof (Elf64_Sym *), dt_module_symcomp64); dt_module_strtab = NULL; } static GElf_Sym * dt_module_symgelf32(const Elf32_Sym *src, GElf_Sym *dst) { if (dst != NULL) { dst->st_name = src->st_name; dst->st_info = src->st_info; dst->st_other = src->st_other; dst->st_shndx = src->st_shndx; dst->st_value = src->st_value; dst->st_size = src->st_size; } return (dst); } static GElf_Sym * dt_module_symgelf64(const Elf64_Sym *src, GElf_Sym *dst) { if (dst != NULL) bcopy(src, dst, sizeof (GElf_Sym)); return (dst); } static GElf_Sym * dt_module_symname32(dt_module_t *dmp, const char *name, GElf_Sym *symp, uint_t *idp) { const Elf32_Sym *symtab = dmp->dm_symtab.cts_data; const char *strtab = dmp->dm_strtab.cts_data; const Elf32_Sym *sym; const dt_sym_t *dsp; uint_t i, h; if (dmp->dm_nsymelems == 0) return (NULL); h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets; for (i = dmp->dm_symbuckets[h]; i != 0; i = dsp->ds_next) { dsp = &dmp->dm_symchains[i]; sym = symtab + dsp->ds_symid; if (strcmp(name, strtab + sym->st_name) == 0) { if (idp != NULL) *idp = dsp->ds_symid; return (dt_module_symgelf32(sym, symp)); } } return (NULL); } static GElf_Sym * dt_module_symname64(dt_module_t *dmp, const char *name, GElf_Sym *symp, uint_t *idp) { const Elf64_Sym *symtab = dmp->dm_symtab.cts_data; const char *strtab = dmp->dm_strtab.cts_data; const Elf64_Sym *sym; const dt_sym_t *dsp; uint_t i, h; if (dmp->dm_nsymelems == 0) return (NULL); h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets; for (i = dmp->dm_symbuckets[h]; i != 0; i = dsp->ds_next) { dsp = &dmp->dm_symchains[i]; sym = symtab + dsp->ds_symid; if (strcmp(name, strtab + sym->st_name) == 0) { if (idp != NULL) *idp = dsp->ds_symid; return (dt_module_symgelf64(sym, symp)); } } return (NULL); } static GElf_Sym * dt_module_symaddr32(dt_module_t *dmp, GElf_Addr addr, GElf_Sym *symp, uint_t *idp) { const Elf32_Sym **asmap = (const Elf32_Sym **)dmp->dm_asmap; const Elf32_Sym *symtab = dmp->dm_symtab.cts_data; const Elf32_Sym *sym; uint_t i, mid, lo = 0, hi = dmp->dm_aslen - 1; Elf32_Addr v; if (dmp->dm_aslen == 0) return (NULL); while (hi - lo > 1) { mid = (lo + hi) / 2; if (addr >= asmap[mid]->st_value) lo = mid; else hi = mid; } i = addr < asmap[hi]->st_value ? lo : hi; sym = asmap[i]; v = sym->st_value; /* * If the previous entry has the same value, improve our choice. The * order of equal-valued symbols is determined by the comparison func. */ while (i-- != 0 && asmap[i]->st_value == v) sym = asmap[i]; if (addr - sym->st_value < MAX(sym->st_size, 1)) { if (idp != NULL) *idp = (uint_t)(sym - symtab); return (dt_module_symgelf32(sym, symp)); } return (NULL); } static GElf_Sym * dt_module_symaddr64(dt_module_t *dmp, GElf_Addr addr, GElf_Sym *symp, uint_t *idp) { const Elf64_Sym **asmap = (const Elf64_Sym **)dmp->dm_asmap; const Elf64_Sym *symtab = dmp->dm_symtab.cts_data; const Elf64_Sym *sym; uint_t i, mid, lo = 0, hi = dmp->dm_aslen - 1; Elf64_Addr v; if (dmp->dm_aslen == 0) return (NULL); while (hi - lo > 1) { mid = (lo + hi) / 2; if (addr >= asmap[mid]->st_value) lo = mid; else hi = mid; } i = addr < asmap[hi]->st_value ? lo : hi; sym = asmap[i]; v = sym->st_value; /* * If the previous entry has the same value, improve our choice. The * order of equal-valued symbols is determined by the comparison func. */ while (i-- != 0 && asmap[i]->st_value == v) sym = asmap[i]; if (addr - sym->st_value < MAX(sym->st_size, 1)) { if (idp != NULL) *idp = (uint_t)(sym - symtab); return (dt_module_symgelf64(sym, symp)); } return (NULL); } static const dt_modops_t dt_modops_32 = { dt_module_syminit32, dt_module_symsort32, dt_module_symname32, dt_module_symaddr32 }; static const dt_modops_t dt_modops_64 = { dt_module_syminit64, dt_module_symsort64, dt_module_symname64, dt_module_symaddr64 }; dt_module_t * dt_module_create(dtrace_hdl_t *dtp, const char *name) { uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets; dt_module_t *dmp; for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) { if (strcmp(dmp->dm_name, name) == 0) return (dmp); } if ((dmp = malloc(sizeof (dt_module_t))) == NULL) return (NULL); /* caller must handle allocation failure */ bzero(dmp, sizeof (dt_module_t)); (void) strlcpy(dmp->dm_name, name, sizeof (dmp->dm_name)); dt_list_append(&dtp->dt_modlist, dmp); dmp->dm_next = dtp->dt_mods[h]; dtp->dt_mods[h] = dmp; dtp->dt_nmods++; if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64) dmp->dm_ops = &dt_modops_64; else dmp->dm_ops = &dt_modops_32; return (dmp); } dt_module_t * dt_module_lookup_by_name(dtrace_hdl_t *dtp, const char *name) { uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets; dt_module_t *dmp; for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) { if (strcmp(dmp->dm_name, name) == 0) return (dmp); } return (NULL); } /*ARGSUSED*/ dt_module_t * dt_module_lookup_by_ctf(dtrace_hdl_t *dtp, ctf_file_t *ctfp) { return (ctfp ? ctf_getspecific(ctfp) : NULL); } static int dt_module_load_sect(dtrace_hdl_t *dtp, dt_module_t *dmp, ctf_sect_t *ctsp) { const char *s; size_t shstrs; GElf_Shdr sh; Elf_Data *dp; Elf_Scn *sp; if (elf_getshdrstrndx(dmp->dm_elf, &shstrs) == -1) return (dt_set_errno(dtp, EDT_NOTLOADED)); for (sp = NULL; (sp = elf_nextscn(dmp->dm_elf, sp)) != NULL; ) { if (gelf_getshdr(sp, &sh) == NULL || sh.sh_type == SHT_NULL || (s = elf_strptr(dmp->dm_elf, shstrs, sh.sh_name)) == NULL) continue; /* skip any malformed sections */ if (sh.sh_type == ctsp->cts_type && sh.sh_entsize == ctsp->cts_entsize && strcmp(s, ctsp->cts_name) == 0) break; /* section matches specification */ } /* * If the section isn't found, return success but leave cts_data set * to NULL and cts_size set to zero for our caller. */ if (sp == NULL || (dp = elf_getdata(sp, NULL)) == NULL) return (0); #if defined(sun) ctsp->cts_data = dp->d_buf; #else if ((ctsp->cts_data = malloc(dp->d_size)) == NULL) return (0); memcpy(ctsp->cts_data, dp->d_buf, dp->d_size); #endif ctsp->cts_size = dp->d_size; dt_dprintf("loaded %s [%s] (%lu bytes)\n", dmp->dm_name, ctsp->cts_name, (ulong_t)ctsp->cts_size); return (0); } int dt_module_load(dtrace_hdl_t *dtp, dt_module_t *dmp) { if (dmp->dm_flags & DT_DM_LOADED) return (0); /* module is already loaded */ dmp->dm_ctdata.cts_name = ".SUNW_ctf"; dmp->dm_ctdata.cts_type = SHT_PROGBITS; dmp->dm_ctdata.cts_flags = 0; dmp->dm_ctdata.cts_data = NULL; dmp->dm_ctdata.cts_size = 0; dmp->dm_ctdata.cts_entsize = 0; dmp->dm_ctdata.cts_offset = 0; dmp->dm_symtab.cts_name = ".symtab"; dmp->dm_symtab.cts_type = SHT_SYMTAB; dmp->dm_symtab.cts_flags = 0; dmp->dm_symtab.cts_data = NULL; dmp->dm_symtab.cts_size = 0; dmp->dm_symtab.cts_entsize = dmp->dm_ops == &dt_modops_64 ? sizeof (Elf64_Sym) : sizeof (Elf32_Sym); dmp->dm_symtab.cts_offset = 0; dmp->dm_strtab.cts_name = ".strtab"; dmp->dm_strtab.cts_type = SHT_STRTAB; dmp->dm_strtab.cts_flags = 0; dmp->dm_strtab.cts_data = NULL; dmp->dm_strtab.cts_size = 0; dmp->dm_strtab.cts_entsize = 0; dmp->dm_strtab.cts_offset = 0; /* * Attempt to load the module's CTF section, symbol table section, and * string table section. Note that modules may not contain CTF data: * this will result in a successful load_sect but data of size zero. * We will then fail if dt_module_getctf() is called, as shown below. */ if (dt_module_load_sect(dtp, dmp, &dmp->dm_ctdata) == -1 || dt_module_load_sect(dtp, dmp, &dmp->dm_symtab) == -1 || dt_module_load_sect(dtp, dmp, &dmp->dm_strtab) == -1) { dt_module_unload(dtp, dmp); return (-1); /* dt_errno is set for us */ } /* * Allocate the hash chains and hash buckets for symbol name lookup. * This is relatively simple since the symbol table is of fixed size * and is known in advance. We allocate one extra element since we * use element indices instead of pointers and zero is our sentinel. */ dmp->dm_nsymelems = dmp->dm_symtab.cts_size / dmp->dm_symtab.cts_entsize; dmp->dm_nsymbuckets = _dtrace_strbuckets; dmp->dm_symfree = 1; /* first free element is index 1 */ dmp->dm_symbuckets = malloc(sizeof (uint_t) * dmp->dm_nsymbuckets); dmp->dm_symchains = malloc(sizeof (dt_sym_t) * dmp->dm_nsymelems + 1); if (dmp->dm_symbuckets == NULL || dmp->dm_symchains == NULL) { dt_module_unload(dtp, dmp); return (dt_set_errno(dtp, EDT_NOMEM)); } bzero(dmp->dm_symbuckets, sizeof (uint_t) * dmp->dm_nsymbuckets); bzero(dmp->dm_symchains, sizeof (dt_sym_t) * dmp->dm_nsymelems + 1); /* * Iterate over the symbol table data buffer and insert each symbol * name into the name hash if the name and type are valid. Then * allocate the address map, fill it in, and sort it. */ dmp->dm_asrsv = dmp->dm_ops->do_syminit(dmp); dt_dprintf("hashed %s [%s] (%u symbols)\n", dmp->dm_name, dmp->dm_symtab.cts_name, dmp->dm_symfree - 1); if ((dmp->dm_asmap = malloc(sizeof (void *) * dmp->dm_asrsv)) == NULL) { dt_module_unload(dtp, dmp); return (dt_set_errno(dtp, EDT_NOMEM)); } dmp->dm_ops->do_symsort(dmp); dt_dprintf("sorted %s [%s] (%u symbols)\n", dmp->dm_name, dmp->dm_symtab.cts_name, dmp->dm_aslen); dmp->dm_flags |= DT_DM_LOADED; return (0); } ctf_file_t * dt_module_getctf(dtrace_hdl_t *dtp, dt_module_t *dmp) { const char *parent; dt_module_t *pmp; ctf_file_t *pfp; int model; if (dmp->dm_ctfp != NULL || dt_module_load(dtp, dmp) != 0) return (dmp->dm_ctfp); if (dmp->dm_ops == &dt_modops_64) model = CTF_MODEL_LP64; else model = CTF_MODEL_ILP32; /* * If the data model of the module does not match our program data * model, then do not permit CTF from this module to be opened and * returned to the compiler. If we support mixed data models in the * future for combined kernel/user tracing, this can be removed. */ if (dtp->dt_conf.dtc_ctfmodel != model) { (void) dt_set_errno(dtp, EDT_DATAMODEL); return (NULL); } if (dmp->dm_ctdata.cts_size == 0) { (void) dt_set_errno(dtp, EDT_NOCTF); return (NULL); } dmp->dm_ctfp = ctf_bufopen(&dmp->dm_ctdata, &dmp->dm_symtab, &dmp->dm_strtab, &dtp->dt_ctferr); if (dmp->dm_ctfp == NULL) { (void) dt_set_errno(dtp, EDT_CTF); return (NULL); } (void) ctf_setmodel(dmp->dm_ctfp, model); ctf_setspecific(dmp->dm_ctfp, dmp); if ((parent = ctf_parent_name(dmp->dm_ctfp)) != NULL) { if ((pmp = dt_module_create(dtp, parent)) == NULL || (pfp = dt_module_getctf(dtp, pmp)) == NULL) { if (pmp == NULL) (void) dt_set_errno(dtp, EDT_NOMEM); goto err; } if (ctf_import(dmp->dm_ctfp, pfp) == CTF_ERR) { dtp->dt_ctferr = ctf_errno(dmp->dm_ctfp); (void) dt_set_errno(dtp, EDT_CTF); goto err; } } dt_dprintf("loaded CTF container for %s (%p)\n", dmp->dm_name, (void *)dmp->dm_ctfp); return (dmp->dm_ctfp); err: ctf_close(dmp->dm_ctfp); dmp->dm_ctfp = NULL; return (NULL); } /*ARGSUSED*/ void dt_module_unload(dtrace_hdl_t *dtp, dt_module_t *dmp) { ctf_close(dmp->dm_ctfp); dmp->dm_ctfp = NULL; #if !defined(sun) if (dmp->dm_ctdata.cts_data != NULL) { free(dmp->dm_ctdata.cts_data); } if (dmp->dm_symtab.cts_data != NULL) { free(dmp->dm_symtab.cts_data); } if (dmp->dm_strtab.cts_data != NULL) { free(dmp->dm_strtab.cts_data); } #endif bzero(&dmp->dm_ctdata, sizeof (ctf_sect_t)); bzero(&dmp->dm_symtab, sizeof (ctf_sect_t)); bzero(&dmp->dm_strtab, sizeof (ctf_sect_t)); if (dmp->dm_symbuckets != NULL) { free(dmp->dm_symbuckets); dmp->dm_symbuckets = NULL; } if (dmp->dm_symchains != NULL) { free(dmp->dm_symchains); dmp->dm_symchains = NULL; } if (dmp->dm_asmap != NULL) { free(dmp->dm_asmap); dmp->dm_asmap = NULL; } #if defined(__FreeBSD__) if (dmp->dm_sec_offsets != NULL) { free(dmp->dm_sec_offsets); dmp->dm_sec_offsets = NULL; } #endif dmp->dm_symfree = 0; dmp->dm_nsymbuckets = 0; dmp->dm_nsymelems = 0; dmp->dm_asrsv = 0; dmp->dm_aslen = 0; dmp->dm_text_va = 0; dmp->dm_text_size = 0; dmp->dm_data_va = 0; dmp->dm_data_size = 0; dmp->dm_bss_va = 0; dmp->dm_bss_size = 0; if (dmp->dm_extern != NULL) { dt_idhash_destroy(dmp->dm_extern); dmp->dm_extern = NULL; } (void) elf_end(dmp->dm_elf); dmp->dm_elf = NULL; dmp->dm_flags &= ~DT_DM_LOADED; } void dt_module_destroy(dtrace_hdl_t *dtp, dt_module_t *dmp) { uint_t h = dt_strtab_hash(dmp->dm_name, NULL) % dtp->dt_modbuckets; dt_module_t **dmpp = &dtp->dt_mods[h]; dt_list_delete(&dtp->dt_modlist, dmp); assert(dtp->dt_nmods != 0); dtp->dt_nmods--; /* * Now remove this module from its hash chain. We expect to always * find the module on its hash chain, so in this loop we assert that * we don't run off the end of the list. */ while (*dmpp != dmp) { dmpp = &((*dmpp)->dm_next); assert(*dmpp != NULL); } *dmpp = dmp->dm_next; dt_module_unload(dtp, dmp); free(dmp); } /* * Insert a new external symbol reference into the specified module. The new * symbol will be marked as undefined and is assigned a symbol index beyond * any existing cached symbols from this module. We use the ident's di_data * field to store a pointer to a copy of the dtrace_syminfo_t for this symbol. */ dt_ident_t * dt_module_extern(dtrace_hdl_t *dtp, dt_module_t *dmp, const char *name, const dtrace_typeinfo_t *tip) { dtrace_syminfo_t *sip; dt_ident_t *idp; uint_t id; if (dmp->dm_extern == NULL && (dmp->dm_extern = dt_idhash_create( "extern", NULL, dmp->dm_nsymelems, UINT_MAX)) == NULL) { (void) dt_set_errno(dtp, EDT_NOMEM); return (NULL); } if (dt_idhash_nextid(dmp->dm_extern, &id) == -1) { (void) dt_set_errno(dtp, EDT_SYMOFLOW); return (NULL); } if ((sip = malloc(sizeof (dtrace_syminfo_t))) == NULL) { (void) dt_set_errno(dtp, EDT_NOMEM); return (NULL); } idp = dt_idhash_insert(dmp->dm_extern, name, DT_IDENT_SYMBOL, 0, id, _dtrace_symattr, 0, &dt_idops_thaw, NULL, dtp->dt_gen); if (idp == NULL) { (void) dt_set_errno(dtp, EDT_NOMEM); free(sip); return (NULL); } sip->dts_object = dmp->dm_name; sip->dts_name = idp->di_name; sip->dts_id = idp->di_id; idp->di_data = sip; idp->di_ctfp = tip->dtt_ctfp; idp->di_type = tip->dtt_type; return (idp); } const char * dt_module_modelname(dt_module_t *dmp) { if (dmp->dm_ops == &dt_modops_64) return ("64-bit"); else return ("32-bit"); } /* * Update our module cache by adding an entry for the specified module 'name'. * We create the dt_module_t and populate it using /system/object//. * * On FreeBSD, the module name is passed as the full module file name, * including the path. */ static void #if defined(sun) dt_module_update(dtrace_hdl_t *dtp, const char *name) #else dt_module_update(dtrace_hdl_t *dtp, struct kld_file_stat *k_stat) #endif { char fname[MAXPATHLEN]; struct stat64 st; int fd, err, bits; dt_module_t *dmp; const char *s; size_t shstrs; GElf_Shdr sh; Elf_Data *dp; Elf_Scn *sp; #if defined(sun) (void) snprintf(fname, sizeof (fname), "%s/%s/object", OBJFS_ROOT, name); #else GElf_Ehdr ehdr; GElf_Phdr ph; char name[MAXPATHLEN]; uintptr_t mapbase, alignmask; int i = 0; int is_elf_obj; (void) strlcpy(name, k_stat->name, sizeof(name)); (void) strlcpy(fname, k_stat->pathname, sizeof(fname)); #endif if ((fd = open(fname, O_RDONLY)) == -1 || fstat64(fd, &st) == -1 || (dmp = dt_module_create(dtp, name)) == NULL) { dt_dprintf("failed to open %s: %s\n", fname, strerror(errno)); (void) close(fd); return; } /* * Since the module can unload out from under us (and /system/object * will return ENOENT), tell libelf to cook the entire file now and * then close the underlying file descriptor immediately. If this * succeeds, we know that we can continue safely using dmp->dm_elf. */ dmp->dm_elf = elf_begin(fd, ELF_C_READ, NULL); err = elf_cntl(dmp->dm_elf, ELF_C_FDREAD); (void) close(fd); if (dmp->dm_elf == NULL || err == -1 || elf_getshdrstrndx(dmp->dm_elf, &shstrs) == -1) { dt_dprintf("failed to load %s: %s\n", fname, elf_errmsg(elf_errno())); dt_module_destroy(dtp, dmp); return; } switch (gelf_getclass(dmp->dm_elf)) { case ELFCLASS32: dmp->dm_ops = &dt_modops_32; bits = 32; break; case ELFCLASS64: dmp->dm_ops = &dt_modops_64; bits = 64; break; default: dt_dprintf("failed to load %s: unknown ELF class\n", fname); dt_module_destroy(dtp, dmp); return; } #if defined(__FreeBSD__) mapbase = (uintptr_t)k_stat->address; gelf_getehdr(dmp->dm_elf, &ehdr); is_elf_obj = (ehdr.e_type == ET_REL); if (is_elf_obj) { dmp->dm_sec_offsets = malloc(ehdr.e_shnum * sizeof(*dmp->dm_sec_offsets)); if (dmp->dm_sec_offsets == NULL) { dt_dprintf("failed to allocate memory\n"); dt_module_destroy(dtp, dmp); return; } } #endif /* * Iterate over the section headers locating various sections of * interest and use their attributes to flesh out the dt_module_t. */ for (sp = NULL; (sp = elf_nextscn(dmp->dm_elf, sp)) != NULL; ) { if (gelf_getshdr(sp, &sh) == NULL || sh.sh_type == SHT_NULL || (s = elf_strptr(dmp->dm_elf, shstrs, sh.sh_name)) == NULL) continue; /* skip any malformed sections */ #if defined(__FreeBSD__) if (sh.sh_size == 0) continue; if (sh.sh_type == SHT_PROGBITS || sh.sh_type == SHT_NOBITS) { alignmask = sh.sh_addralign - 1; mapbase += alignmask; mapbase &= ~alignmask; sh.sh_addr = mapbase; if (is_elf_obj) dmp->dm_sec_offsets[elf_ndxscn(sp)] = sh.sh_addr; mapbase += sh.sh_size; } #endif if (strcmp(s, ".text") == 0) { dmp->dm_text_size = sh.sh_size; dmp->dm_text_va = sh.sh_addr; } else if (strcmp(s, ".data") == 0) { dmp->dm_data_size = sh.sh_size; dmp->dm_data_va = sh.sh_addr; } else if (strcmp(s, ".bss") == 0) { dmp->dm_bss_size = sh.sh_size; dmp->dm_bss_va = sh.sh_addr; } else if (strcmp(s, ".info") == 0 && (dp = elf_getdata(sp, NULL)) != NULL) { bcopy(dp->d_buf, &dmp->dm_info, MIN(sh.sh_size, sizeof (dmp->dm_info))); } else if (strcmp(s, ".filename") == 0 && (dp = elf_getdata(sp, NULL)) != NULL) { (void) strlcpy(dmp->dm_file, dp->d_buf, sizeof (dmp->dm_file)); } } dmp->dm_flags |= DT_DM_KERNEL; #if defined(sun) dmp->dm_modid = (int)OBJFS_MODID(st.st_ino); #else /* * Include .rodata and special sections into .text. * This depends on default section layout produced by GNU ld * for ELF objects and libraries: * [Text][R/O data][R/W data][Dynamic][BSS][Non loadable] */ dmp->dm_text_size = dmp->dm_data_va - dmp->dm_text_va; #if defined(__i386__) /* * Find the first load section and figure out the relocation * offset for the symbols. The kernel module will not need * relocation, but the kernel linker modules will. */ for (i = 0; gelf_getphdr(dmp->dm_elf, i, &ph) != NULL; i++) { if (ph.p_type == PT_LOAD) { dmp->dm_reloc_offset = k_stat->address - ph.p_vaddr; break; } } #endif #endif if (dmp->dm_info.objfs_info_primary) dmp->dm_flags |= DT_DM_PRIMARY; dt_dprintf("opened %d-bit module %s (%s) [%d]\n", bits, dmp->dm_name, dmp->dm_file, dmp->dm_modid); } /* * Unload all the loaded modules and then refresh the module cache with the * latest list of loaded modules and their address ranges. */ void dtrace_update(dtrace_hdl_t *dtp) { dt_module_t *dmp; DIR *dirp; #if defined(__FreeBSD__) int fileid; #endif for (dmp = dt_list_next(&dtp->dt_modlist); dmp != NULL; dmp = dt_list_next(dmp)) dt_module_unload(dtp, dmp); #if defined(sun) /* * Open /system/object and attempt to create a libdtrace module for * each kernel module that is loaded on the current system. */ if (!(dtp->dt_oflags & DTRACE_O_NOSYS) && (dirp = opendir(OBJFS_ROOT)) != NULL) { struct dirent *dp; while ((dp = readdir(dirp)) != NULL) { if (dp->d_name[0] != '.') dt_module_update(dtp, dp->d_name); } (void) closedir(dirp); } #elif defined(__FreeBSD__) /* * Use FreeBSD's kernel loader interface to discover what kernel * modules are loaded and create a libdtrace module for each one. */ for (fileid = kldnext(0); fileid > 0; fileid = kldnext(fileid)) { struct kld_file_stat k_stat; k_stat.version = sizeof(k_stat); if (kldstat(fileid, &k_stat) == 0) dt_module_update(dtp, &k_stat); } #endif /* * Look up all the macro identifiers and set di_id to the latest value. * This code collaborates with dt_lex.l on the use of di_id. We will * need to implement something fancier if we need to support non-ints. */ dt_idhash_lookup(dtp->dt_macros, "egid")->di_id = getegid(); dt_idhash_lookup(dtp->dt_macros, "euid")->di_id = geteuid(); dt_idhash_lookup(dtp->dt_macros, "gid")->di_id = getgid(); dt_idhash_lookup(dtp->dt_macros, "pid")->di_id = getpid(); dt_idhash_lookup(dtp->dt_macros, "pgid")->di_id = getpgid(0); dt_idhash_lookup(dtp->dt_macros, "ppid")->di_id = getppid(); #if defined(sun) dt_idhash_lookup(dtp->dt_macros, "projid")->di_id = getprojid(); #endif dt_idhash_lookup(dtp->dt_macros, "sid")->di_id = getsid(0); #if defined(sun) dt_idhash_lookup(dtp->dt_macros, "taskid")->di_id = gettaskid(); #endif dt_idhash_lookup(dtp->dt_macros, "uid")->di_id = getuid(); /* * Cache the pointers to the modules representing the base executable * and the run-time linker in the dtrace client handle. Note that on * x86 krtld is folded into unix, so if we don't find it, use unix * instead. */ dtp->dt_exec = dt_module_lookup_by_name(dtp, "genunix"); dtp->dt_rtld = dt_module_lookup_by_name(dtp, "krtld"); if (dtp->dt_rtld == NULL) dtp->dt_rtld = dt_module_lookup_by_name(dtp, "unix"); /* * If this is the first time we are initializing the module list, * remove the module for genunix from the module list and then move it * to the front of the module list. We do this so that type and symbol * queries encounter genunix and thereby optimize for the common case * in dtrace_lookup_by_name() and dtrace_lookup_by_type(), below. */ if (dtp->dt_exec != NULL && dtp->dt_cdefs == NULL && dtp->dt_ddefs == NULL) { dt_list_delete(&dtp->dt_modlist, dtp->dt_exec); dt_list_prepend(&dtp->dt_modlist, dtp->dt_exec); } } static dt_module_t * dt_module_from_object(dtrace_hdl_t *dtp, const char *object) { int err = EDT_NOMOD; dt_module_t *dmp; switch ((uintptr_t)object) { case (uintptr_t)DTRACE_OBJ_EXEC: dmp = dtp->dt_exec; break; case (uintptr_t)DTRACE_OBJ_RTLD: dmp = dtp->dt_rtld; break; case (uintptr_t)DTRACE_OBJ_CDEFS: dmp = dtp->dt_cdefs; break; case (uintptr_t)DTRACE_OBJ_DDEFS: dmp = dtp->dt_ddefs; break; default: dmp = dt_module_create(dtp, object); err = EDT_NOMEM; } if (dmp == NULL) (void) dt_set_errno(dtp, err); return (dmp); } /* * Exported interface to look up a symbol by name. We return the GElf_Sym and * complete symbol information for the matching symbol. */ int dtrace_lookup_by_name(dtrace_hdl_t *dtp, const char *object, const char *name, GElf_Sym *symp, dtrace_syminfo_t *sip) { dt_module_t *dmp; dt_ident_t *idp; uint_t n, id; GElf_Sym sym; uint_t mask = 0; /* mask of dt_module flags to match */ uint_t bits = 0; /* flag bits that must be present */ if (object != DTRACE_OBJ_EVERY && object != DTRACE_OBJ_KMODS && object != DTRACE_OBJ_UMODS) { if ((dmp = dt_module_from_object(dtp, object)) == NULL) return (-1); /* dt_errno is set for us */ if (dt_module_load(dtp, dmp) == -1) return (-1); /* dt_errno is set for us */ n = 1; } else { if (object == DTRACE_OBJ_KMODS) mask = bits = DT_DM_KERNEL; else if (object == DTRACE_OBJ_UMODS) mask = DT_DM_KERNEL; dmp = dt_list_next(&dtp->dt_modlist); n = dtp->dt_nmods; } if (symp == NULL) symp = &sym; for (; n > 0; n--, dmp = dt_list_next(dmp)) { if ((dmp->dm_flags & mask) != bits) continue; /* failed to match required attributes */ if (dt_module_load(dtp, dmp) == -1) continue; /* failed to load symbol table */ if (dmp->dm_ops->do_symname(dmp, name, symp, &id) != NULL) { if (sip != NULL) { sip->dts_object = dmp->dm_name; sip->dts_name = (const char *) dmp->dm_strtab.cts_data + symp->st_name; sip->dts_id = id; } return (0); } if (dmp->dm_extern != NULL && (idp = dt_idhash_lookup(dmp->dm_extern, name)) != NULL) { if (symp != &sym) { symp->st_name = (uintptr_t)idp->di_name; symp->st_info = GELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); symp->st_other = 0; symp->st_shndx = SHN_UNDEF; symp->st_value = 0; symp->st_size = ctf_type_size(idp->di_ctfp, idp->di_type); } if (sip != NULL) { sip->dts_object = dmp->dm_name; sip->dts_name = idp->di_name; sip->dts_id = idp->di_id; } return (0); } } return (dt_set_errno(dtp, EDT_NOSYM)); } /* * Exported interface to look up a symbol by address. We return the GElf_Sym * and complete symbol information for the matching symbol. */ int dtrace_lookup_by_addr(dtrace_hdl_t *dtp, GElf_Addr addr, GElf_Sym *symp, dtrace_syminfo_t *sip) { dt_module_t *dmp; uint_t id; const dtrace_vector_t *v = dtp->dt_vector; if (v != NULL) return (v->dtv_lookup_by_addr(dtp->dt_varg, addr, symp, sip)); for (dmp = dt_list_next(&dtp->dt_modlist); dmp != NULL; dmp = dt_list_next(dmp)) { if (addr - dmp->dm_text_va < dmp->dm_text_size || addr - dmp->dm_data_va < dmp->dm_data_size || addr - dmp->dm_bss_va < dmp->dm_bss_size) break; } if (dmp == NULL) return (dt_set_errno(dtp, EDT_NOSYMADDR)); if (dt_module_load(dtp, dmp) == -1) return (-1); /* dt_errno is set for us */ if (symp != NULL) { if (dmp->dm_ops->do_symaddr(dmp, addr, symp, &id) == NULL) return (dt_set_errno(dtp, EDT_NOSYMADDR)); } if (sip != NULL) { sip->dts_object = dmp->dm_name; if (symp != NULL) { sip->dts_name = (const char *) dmp->dm_strtab.cts_data + symp->st_name; sip->dts_id = id; } else { sip->dts_name = NULL; sip->dts_id = 0; } } return (0); } int dtrace_lookup_by_type(dtrace_hdl_t *dtp, const char *object, const char *name, dtrace_typeinfo_t *tip) { dtrace_typeinfo_t ti; dt_module_t *dmp; int found = 0; ctf_id_t id; uint_t n; int justone; uint_t mask = 0; /* mask of dt_module flags to match */ uint_t bits = 0; /* flag bits that must be present */ if (object != DTRACE_OBJ_EVERY && object != DTRACE_OBJ_KMODS && object != DTRACE_OBJ_UMODS) { if ((dmp = dt_module_from_object(dtp, object)) == NULL) return (-1); /* dt_errno is set for us */ if (dt_module_load(dtp, dmp) == -1) return (-1); /* dt_errno is set for us */ n = 1; justone = 1; } else { if (object == DTRACE_OBJ_KMODS) mask = bits = DT_DM_KERNEL; else if (object == DTRACE_OBJ_UMODS) mask = DT_DM_KERNEL; dmp = dt_list_next(&dtp->dt_modlist); n = dtp->dt_nmods; justone = 0; } if (tip == NULL) tip = &ti; for (; n > 0; n--, dmp = dt_list_next(dmp)) { if ((dmp->dm_flags & mask) != bits) continue; /* failed to match required attributes */ /* * If we can't load the CTF container, continue on to the next * module. If our search was scoped to only one module then * return immediately leaving dt_errno unmodified. */ if (dt_module_getctf(dtp, dmp) == NULL) { if (justone) return (-1); continue; } /* * Look up the type in the module's CTF container. If our * match is a forward declaration tag, save this choice in * 'tip' and keep going in the hope that we will locate the * underlying structure definition. Otherwise just return. */ if ((id = ctf_lookup_by_name(dmp->dm_ctfp, name)) != CTF_ERR) { tip->dtt_object = dmp->dm_name; tip->dtt_ctfp = dmp->dm_ctfp; tip->dtt_type = id; if (ctf_type_kind(dmp->dm_ctfp, ctf_type_resolve( dmp->dm_ctfp, id)) != CTF_K_FORWARD) return (0); found++; } } if (found == 0) return (dt_set_errno(dtp, EDT_NOTYPE)); return (0); } int dtrace_symbol_type(dtrace_hdl_t *dtp, const GElf_Sym *symp, const dtrace_syminfo_t *sip, dtrace_typeinfo_t *tip) { dt_module_t *dmp; tip->dtt_object = NULL; tip->dtt_ctfp = NULL; tip->dtt_type = CTF_ERR; if ((dmp = dt_module_lookup_by_name(dtp, sip->dts_object)) == NULL) return (dt_set_errno(dtp, EDT_NOMOD)); if (symp->st_shndx == SHN_UNDEF && dmp->dm_extern != NULL) { dt_ident_t *idp = dt_idhash_lookup(dmp->dm_extern, sip->dts_name); if (idp == NULL) return (dt_set_errno(dtp, EDT_NOSYM)); tip->dtt_ctfp = idp->di_ctfp; tip->dtt_type = idp->di_type; } else if (GELF_ST_TYPE(symp->st_info) != STT_FUNC) { if (dt_module_getctf(dtp, dmp) == NULL) return (-1); /* errno is set for us */ tip->dtt_ctfp = dmp->dm_ctfp; tip->dtt_type = ctf_lookup_by_symbol(dmp->dm_ctfp, sip->dts_id); if (tip->dtt_type == CTF_ERR) { dtp->dt_ctferr = ctf_errno(tip->dtt_ctfp); return (dt_set_errno(dtp, EDT_CTF)); } } else { tip->dtt_ctfp = DT_FPTR_CTFP(dtp); tip->dtt_type = DT_FPTR_TYPE(dtp); } tip->dtt_object = dmp->dm_name; return (0); } static dtrace_objinfo_t * dt_module_info(const dt_module_t *dmp, dtrace_objinfo_t *dto) { dto->dto_name = dmp->dm_name; dto->dto_file = dmp->dm_file; dto->dto_id = dmp->dm_modid; dto->dto_flags = 0; if (dmp->dm_flags & DT_DM_KERNEL) dto->dto_flags |= DTRACE_OBJ_F_KERNEL; if (dmp->dm_flags & DT_DM_PRIMARY) dto->dto_flags |= DTRACE_OBJ_F_PRIMARY; dto->dto_text_va = dmp->dm_text_va; dto->dto_text_size = dmp->dm_text_size; dto->dto_data_va = dmp->dm_data_va; dto->dto_data_size = dmp->dm_data_size; dto->dto_bss_va = dmp->dm_bss_va; dto->dto_bss_size = dmp->dm_bss_size; return (dto); } int dtrace_object_iter(dtrace_hdl_t *dtp, dtrace_obj_f *func, void *data) { const dt_module_t *dmp = dt_list_next(&dtp->dt_modlist); dtrace_objinfo_t dto; int rv; for (; dmp != NULL; dmp = dt_list_next(dmp)) { if ((rv = (*func)(dtp, dt_module_info(dmp, &dto), data)) != 0) return (rv); } return (0); } int dtrace_object_info(dtrace_hdl_t *dtp, const char *object, dtrace_objinfo_t *dto) { dt_module_t *dmp; if (object == DTRACE_OBJ_EVERY || object == DTRACE_OBJ_KMODS || object == DTRACE_OBJ_UMODS || dto == NULL) return (dt_set_errno(dtp, EINVAL)); if ((dmp = dt_module_from_object(dtp, object)) == NULL) return (-1); /* dt_errno is set for us */ if (dt_module_load(dtp, dmp) == -1) return (-1); /* dt_errno is set for us */ (void) dt_module_info(dmp, dto); return (0); }