/* * 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) 1988 AT&T * All Rights Reserved * * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #define ELF_TARGET_AMD64 #include #include #include #include "msg.h" #include "_libld.h" /* * The loader uses a `segment descriptor' list to describe the output * segments it can potentially create. This list is initially seeded * using the templates contained in the sg_desc[] array below. Additional * segments may be added using a mapfile. * * The entries in sg_desc[] must be put in the order defined by the * Segment_id enum, such that a given LD_XXX value can serve as * an index into sg_desc[] for the corresponding descriptor. * * The entries in sg_desc[] are initialized using the SG_DESC_INIT macro * for two reasons: * * 1) The first field of the Sg_desc struct is a program header * entry. ELF32_Phdr and ELF64_Phdr have the same fields, * but their order is different. Use of a macro allows us * to handle this transparently. * 2) Most of the fields in the Sg_desc entries are set to 0. * Use of a macro allows us to hide the clutter. */ #ifdef _ELF64 #define SG_DESC_INIT(id, p_type, p_flags, sg_name, sg_flags) \ { id, { p_type, p_flags, 0, 0, 0, 0, 0, 0}, \ sg_name, 0, 0, NULL, NULL, sg_flags, NULL, 0, NULL} #else #define SG_DESC_INIT(id, p_type, p_flags, sg_name, sg_flags) \ { id, { p_type, 0, 0, 0, 0, 0, p_flags, 0}, \ sg_name, 0, 0, NULL, NULL, sg_flags, NULL, 0, NULL} #endif static const Sg_desc sg_desc[LD_NUM] = { SG_DESC_INIT(LD_PHDR, PT_PHDR, PF_R + PF_X, MSG_ORIG(MSG_ENT_PHDR), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_INTERP, PT_INTERP, PF_R, MSG_ORIG(MSG_ENT_INTERP), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_SUNWCAP, PT_SUNWCAP, PF_R, MSG_ORIG(MSG_ENT_SUNWCAP), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_TEXT, PT_LOAD, PF_R + PF_X, MSG_ORIG(MSG_ENT_TEXT), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_DATA, PT_LOAD, 0, MSG_ORIG(MSG_ENT_DATA), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_BSS, PT_LOAD, 0, MSG_ORIG(MSG_ENT_BSS), (FLG_SG_TYPE | FLG_SG_FLAGS | FLG_SG_DISABLED)), #if defined(_ELF64) /* (amd64-only) */ SG_DESC_INIT(LD_LRODATA, PT_LOAD, PF_R, MSG_ORIG(MSG_ENT_LRODATA), (FLG_SG_TYPE | FLG_SG_FLAGS)), /* (amd64-only) */ SG_DESC_INIT(LD_LDATA, PT_LOAD, 0, MSG_ORIG(MSG_ENT_LDATA), (FLG_SG_TYPE | FLG_SG_FLAGS)), #endif SG_DESC_INIT(LD_DYN, PT_DYNAMIC, 0, MSG_ORIG(MSG_ENT_DYNAMIC), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_DTRACE, PT_SUNWDTRACE, 0, MSG_ORIG(MSG_ENT_DTRACE), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_TLS, PT_TLS, PF_R, MSG_ORIG(MSG_ENT_TLS), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_UNWIND, PT_SUNW_UNWIND, PF_R, MSG_ORIG(MSG_ENT_UNWIND), (FLG_SG_TYPE | FLG_SG_FLAGS)), SG_DESC_INIT(LD_NOTE, PT_NOTE, 0, MSG_ORIG(MSG_ENT_NOTE), FLG_SG_TYPE), SG_DESC_INIT(LD_EXTRA, PT_NULL, 0, MSG_ORIG(MSG_ENT_EXTRA), FLG_SG_TYPE) }; /* * The processing of input files by the link-editor involves matching the * files sections to an `entrance descriptor definition'. The entrance * criteria can be modified further using a mapfile. Each entrance criteria * is associated with a segment descriptor, thus a mapping of input sections * to output segments is maintained. * * Note the trick used for the ec_segment field, which is supposed to be a * pointer to a segment descriptor. We initialize this with the index of the * descriptor, and then turn it into an actual pointer at runtime, once memory * has been allocated and the templates copied. */ static const Ent_desc ent_desc[] = { {NULL, MSG_ORIG(MSG_ENT_NOTE), SHT_NOTE, 0, 0, (Sg_desc *)LD_NOTE, 0, FLG_EC_BUILTIN}, #if defined(_ELF64) /* (amd64-only) */ {NULL, MSG_ORIG(MSG_ENT_LRODATA), NULL, SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE, SHF_ALLOC + SHF_AMD64_LARGE, (Sg_desc *)LD_LRODATA, 0, FLG_EC_BUILTIN}, #endif {NULL, MSG_ORIG(MSG_ENT_TEXT), NULL, SHF_ALLOC + SHF_WRITE, SHF_ALLOC, (Sg_desc *)LD_TEXT, 0, FLG_EC_BUILTIN}, {NULL, MSG_ORIG(MSG_ENT_BSS), SHT_NOBITS, SHF_ALLOC + SHF_WRITE, SHF_ALLOC + SHF_WRITE, (Sg_desc *)LD_BSS, 0, FLG_EC_BUILTIN}, #if defined(_ELF64) /* (amd64-only) */ {NULL, MSG_ORIG(MSG_ENT_LBSS), SHT_NOBITS, SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE, SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE, (Sg_desc *)LD_DATA, 0, FLG_EC_BUILTIN}, {NULL, MSG_ORIG(MSG_ENT_LDATA), NULL, SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE, SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE, (Sg_desc *)LD_LDATA, 0, FLG_EC_BUILTIN}, #endif {NULL, MSG_ORIG(MSG_ENT_DATA), NULL, SHF_ALLOC + SHF_WRITE, SHF_ALLOC + SHF_WRITE, (Sg_desc *)LD_DATA, 0, FLG_EC_BUILTIN}, {NULL, MSG_ORIG(MSG_ENT_EXTRA), 0, 0, 0, (Sg_desc *)LD_EXTRA, 0, FLG_EC_BUILTIN} }; /* * Initialize new entrance and segment descriptors and add them as lists to * the output file descriptor. */ uintptr_t ld_ent_setup(Ofl_desc *ofl, Xword segalign) { const Ent_desc *oenp; Sg_desc *sgp; size_t idx; /* * Initialize the elf library. */ if (elf_version(EV_CURRENT) == EV_NONE) { eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_ELF_LIBELF), EV_CURRENT); return (S_ERROR); } /* * Initialize internal Global Symbol Table AVL tree */ avl_create(&ofl->ofl_symavl, &ld_sym_avl_comp, sizeof (Sym_avlnode), SGSOFFSETOF(Sym_avlnode, sav_node)); /* * Allocate and initialize writable copies of both the entrance and * segment descriptors. * * Note that on non-amd64 targets, this allocates a few more * elements than are needed. For now, we are willing to overallocate * a small amount to simplify the code. */ if ((sgp = libld_malloc(sizeof (sg_desc))) == NULL) return (S_ERROR); (void) memcpy(sgp, sg_desc, sizeof (sg_desc)); /* * The data segment permissions can differ: * * - Architecural/ABI per-platform differences * - Whether the object is built statically or dynamically * * Those segments so affected have their program header flags * set here at runtime, rather than in the sg_desc templates above. */ sgp[LD_DATA].sg_phdr.p_flags = ld_targ.t_m.m_dataseg_perm; sgp[LD_BSS].sg_phdr.p_flags = ld_targ.t_m.m_dataseg_perm; sgp[LD_DYN].sg_phdr.p_flags = ld_targ.t_m.m_dataseg_perm; sgp[LD_DTRACE].sg_phdr.p_flags = ld_targ.t_m.m_dataseg_perm; #if defined(_ELF64) sgp[LD_LDATA].sg_phdr.p_flags = ld_targ.t_m.m_dataseg_perm; sgp[LD_DTRACE].sg_phdr.p_flags |= PF_X; #endif if ((ofl->ofl_flags & FLG_OF_DYNAMIC) == 0) sgp[LD_DATA].sg_phdr.p_flags |= PF_X; /* * Traverse the new entrance descriptor list converting the segment * pointer entries to the absolute address within the new segment * descriptor list. Add each entrance descriptor to the output file * list. */ for (idx = 0, oenp = ent_desc; idx < (sizeof (ent_desc) / sizeof (ent_desc[0])); idx++, oenp++) { Ent_desc *nenp; #if defined(_ELF64) /* Don't use the amd64 entry conditions for non-amd64 targets */ if ((oenp->ec_attrmask & SHF_AMD64_LARGE) && (ld_targ.t_m.m_mach != EM_AMD64)) continue; #endif if ((nenp = alist_append(&(ofl->ofl_ents), oenp, sizeof (Ent_desc), AL_CNT_OFL_ENTRANCE)) == NULL) return (S_ERROR); nenp->ec_segment = &sgp[(long)oenp->ec_segment]; } /* * Traverse the new segment descriptor list adding each entry to the * segment descriptor list. For each loadable segment initialize * a default alignment (ld(1) and ld.so.1 initialize this differently). */ for (idx = 0; idx < LD_NUM; idx++, sgp++) { Phdr *phdr = &(sgp->sg_phdr); #if defined(_ELF64) /* Ignore amd64 segment templates for non-amd64 targets */ switch (idx) { case LD_LRODATA: case LD_LDATA: if ((ld_targ.t_m.m_mach != EM_AMD64)) continue; } #endif if ((aplist_append(&ofl->ofl_segs, sgp, AL_CNT_SEGMENTS)) == NULL) return (S_ERROR); if (phdr->p_type == PT_LOAD) phdr->p_align = segalign; } return (1); }