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/*
* 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 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#define ELF_TARGET_AMD64
#include <stdio.h>
#include <memory.h>
#include <debug.h>
#include "msg.h"
#include "_libld.h"
/*
* Types of segment index.
*/
typedef enum {
LD_PHDR,
LD_INTERP,
LD_SUNWCAP,
LD_TEXT,
LD_DATA,
LD_BSS,
#if defined(_ELF64)
LD_LRODATA, /* (amd64-only) */
LD_LDATA, /* (amd64-only) */
#endif
LD_DYN,
LD_DTRACE,
LD_SUNWBSS,
LD_TLS,
#if defined(_ELF64)
LD_UNWIND, /* (amd64-only) */
#endif
LD_NOTE,
LD_EXTRA,
LD_NUM
} Segment_ndx;
/*
* 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 map file.
*
* The entries in sg_desc[] must be put in the order defined by the
* Segment_ndx 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(p_type, p_flags, sg_name, sg_flags) \
{ { p_type, p_flags, 0, 0, 0, 0, 0, 0}, \
sg_name, 0, 0, NULL, NULL, sg_flags, NULL, 0, 0}
#else
#define SG_DESC_INIT(p_type, p_flags, sg_name, sg_flags) \
{ { p_type, 0, 0, 0, 0, 0, p_flags, 0}, \
sg_name, 0, 0, NULL, NULL, sg_flags, NULL, 0, 0}
#endif
static const Sg_desc sg_desc[LD_NUM] = {
/* LD_PHDR */
SG_DESC_INIT(PT_PHDR, PF_R + PF_X, MSG_ORIG(MSG_ENT_PHDR),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_INTERP */
SG_DESC_INIT(PT_INTERP, PF_R, MSG_ORIG(MSG_ENT_INTERP),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_SUNWCAP */
SG_DESC_INIT(PT_SUNWCAP, PF_R, MSG_ORIG(MSG_ENT_SUNWCAP),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_TEXT */
SG_DESC_INIT(PT_LOAD, PF_R + PF_X, MSG_ORIG(MSG_ENT_TEXT),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_DATA */
SG_DESC_INIT(PT_LOAD, 0, MSG_ORIG(MSG_ENT_DATA),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_BSS */
SG_DESC_INIT(PT_LOAD, 0, MSG_ORIG(MSG_ENT_BSS),
(FLG_SG_TYPE | FLG_SG_FLAGS | FLG_SG_DISABLED)),
#if defined(_ELF64)
/* LD_LRODATA (amd64-only) */
SG_DESC_INIT(PT_LOAD, PF_R, MSG_ORIG(MSG_ENT_LRODATA),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_LDATA (amd64-only) */
SG_DESC_INIT(PT_LOAD, 0, MSG_ORIG(MSG_ENT_LDATA),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
#endif
/* LD_DYN */
SG_DESC_INIT(PT_DYNAMIC, 0, MSG_ORIG(MSG_ENT_DYNAMIC),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_DTRACE */
SG_DESC_INIT(PT_SUNWDTRACE, 0,
MSG_ORIG(MSG_ENT_DTRACE), (FLG_SG_TYPE | FLG_SG_FLAGS)),
/* LD_SUNWBSS */
SG_DESC_INIT(PT_SUNWBSS, 0, MSG_ORIG(MSG_ENT_SUNWBSS), FLG_SG_TYPE),
/* LD_TLS */
SG_DESC_INIT(PT_TLS, PF_R, MSG_ORIG(MSG_ENT_TLS),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
#if defined(_ELF64)
/* LD_UNWIND (amd64-only) */
SG_DESC_INIT(PT_SUNW_UNWIND, PF_R, MSG_ORIG(MSG_ENT_UNWIND),
(FLG_SG_TYPE | FLG_SG_FLAGS)),
#endif
/* LD_NOTE */
SG_DESC_INIT(PT_NOTE, 0, MSG_ORIG(MSG_ENT_NOTE), FLG_SG_TYPE),
/* LD_EXTRA */
SG_DESC_INIT(PT_NULL, 0, MSG_ORIG(MSG_STR_EMPTY), FLG_SG_TYPE)
};
/*
* The input processing of the loader involves matching the sections of its
* input files to an `entrance descriptor definition'. The entrance criteria
* is different for either a static or dynamic linkage, and may even be
* modified further using a map file. 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, NULL}, MSG_ORIG(MSG_SCN_SUNWBSS), NULL,
SHF_ALLOC + SHF_WRITE, SHF_ALLOC + SHF_WRITE,
(Sg_desc *)LD_SUNWBSS, 0, FALSE},
{{NULL, NULL}, NULL, SHT_NOTE, 0, 0,
(Sg_desc *)LD_NOTE, 0, FALSE},
#if defined(_ELF64) /* (amd64-only) */
{{NULL, NULL}, MSG_ORIG(MSG_SCN_LRODATA), NULL,
SHF_ALLOC + SHF_AMD64_LARGE, SHF_ALLOC + SHF_AMD64_LARGE,
(Sg_desc *)LD_LRODATA, 0, FALSE},
#endif
{{NULL, NULL}, NULL, NULL,
SHF_ALLOC + SHF_WRITE, SHF_ALLOC,
(Sg_desc *)LD_TEXT, 0, FALSE},
{{NULL, NULL}, NULL, SHT_NOBITS,
SHF_ALLOC + SHF_WRITE, SHF_ALLOC + SHF_WRITE,
(Sg_desc *)LD_BSS, 0, FALSE},
#if defined(_ELF64) /* (amd64-only) */
{{NULL, NULL}, NULL, SHT_NOBITS,
SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE,
SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE,
(Sg_desc *)LD_DATA, 0, FALSE},
{{NULL, NULL}, NULL, NULL,
SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE,
SHF_ALLOC + SHF_WRITE + SHF_AMD64_LARGE,
(Sg_desc *)LD_LDATA, 0, FALSE},
#endif
{{NULL, NULL}, NULL, NULL,
SHF_ALLOC + SHF_WRITE, SHF_ALLOC + SHF_WRITE,
(Sg_desc *)LD_DATA, 0, FALSE},
{{NULL, NULL}, NULL, 0, 0, 0,
(Sg_desc *)LD_EXTRA, 0, FALSE}
};
/*
* 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)
{
Ent_desc *enp;
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))) == 0)
return (S_ERROR);
(void) memcpy(sgp, sg_desc, sizeof (sg_desc));
if ((enp = libld_malloc(sizeof (ent_desc))) == 0)
return (S_ERROR);
(void) memcpy(enp, ent_desc, sizeof (ent_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) {
sgp[LD_SUNWBSS].sg_phdr.p_flags = ld_targ.t_m.m_dataseg_perm;
} else {
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; idx < (sizeof (ent_desc) / sizeof (ent_desc[0]));
idx++, enp++) {
#if defined(_ELF64)
/* Don't use the amd64 entry conditions for non-amd64 targets */
if ((enp->ec_attrmask & SHF_AMD64_LARGE) &&
(ld_targ.t_m.m_mach != EM_AMD64))
continue;
#endif
enp->ec_segment = &sgp[(long)enp->ec_segment];
if ((list_appendc(&ofl->ofl_ents, enp)) == 0)
return (S_ERROR);
}
/*
* 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:
case LD_UNWIND:
if ((ld_targ.t_m.m_mach != EM_AMD64))
continue;
}
#endif
if ((list_appendc(&ofl->ofl_segs, sgp)) == 0)
return (S_ERROR);
if (phdr->p_type == PT_LOAD)
phdr->p_align = segalign;
}
return (1);
}
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