but did not test... however the only thing this affects in libelf is the header, so I don't expect any functional problems. base/loader/elf_object.cc: Set LIBELF_LINUX to 0 to build on zax. --HG-- extra : convert_revision : d024b33deff6fc8ea6f1d465f76dc8d9d63254ab
253 lines
8.1 KiB
C++
253 lines
8.1 KiB
C++
/*
|
|
* Copyright (c) 2003 The Regents of The University of Michigan
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are
|
|
* met: redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer;
|
|
* redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution;
|
|
* neither the name of the copyright holders nor the names of its
|
|
* contributors may be used to endorse or promote products derived from
|
|
* this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <string>
|
|
|
|
// Because of the -Wundef flag we have to do this
|
|
#define __LIBELF_INTERNAL__ 0
|
|
// counterintuitive, but the flag below causes libelf to define
|
|
// 64-bit elf types that apparently didn't exist in some older
|
|
// versions of Linux. They seem to be there in 2.4.x, so don't
|
|
// set this now (it causes things to break on 64-bit platforms).
|
|
#define __LIBELF64_LINUX 0
|
|
#define __LIBELF_NEED_LINK_H 0
|
|
|
|
#include <libelf/libelf.h>
|
|
#include <libelf/gelf.h>
|
|
|
|
#include "base/loader/elf_object.hh"
|
|
|
|
#include "mem/functional_mem/functional_memory.hh"
|
|
#include "base/loader/symtab.hh"
|
|
|
|
#include "base/trace.hh" // for DPRINTF
|
|
|
|
|
|
using namespace std;
|
|
|
|
ObjectFile *
|
|
ElfObject::tryFile(const string &fname, int fd, size_t len, uint8_t *data)
|
|
{
|
|
Elf *elf;
|
|
GElf_Ehdr ehdr;
|
|
|
|
// check that header matches library version
|
|
assert(elf_version(EV_CURRENT) != EV_NONE);
|
|
|
|
// get a pointer to elf structure
|
|
elf = elf_memory((char*)data,len);
|
|
// will only fail if fd is invalid
|
|
assert(elf != NULL);
|
|
|
|
// Check that we actually have a elf file
|
|
if (gelf_getehdr(elf, &ehdr) ==0) {
|
|
DPRINTFR(Loader, "Not ELF\n");
|
|
elf_end(elf);
|
|
return NULL;
|
|
}
|
|
else {
|
|
if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
|
|
panic("32 bit ELF Binary, Not Supported");
|
|
if (ehdr.e_machine != EM_ALPHA)
|
|
panic("Non Alpha Binary, Not Supported");
|
|
|
|
elf_end(elf);
|
|
|
|
return new ElfObject(fname, fd, len, data,
|
|
ObjectFile::Alpha, ObjectFile::Linux);
|
|
}
|
|
}
|
|
|
|
|
|
ElfObject::ElfObject(const string &_filename, int _fd,
|
|
size_t _len, uint8_t *_data,
|
|
Arch _arch, OpSys _opSys)
|
|
: ObjectFile(_filename, _fd, _len, _data, _arch, _opSys)
|
|
|
|
{
|
|
Elf *elf;
|
|
GElf_Ehdr ehdr;
|
|
|
|
// check that header matches library version
|
|
assert(elf_version(EV_CURRENT) != EV_NONE);
|
|
|
|
// get a pointer to elf structure
|
|
elf = elf_memory((char*)fileData,len);
|
|
// will only fail if fd is invalid
|
|
assert(elf != NULL);
|
|
|
|
// Check that we actually have a elf file
|
|
if (gelf_getehdr(elf, &ehdr) ==0) {
|
|
panic("Not ELF, shouldn't be here");
|
|
}
|
|
|
|
entry = ehdr.e_entry;
|
|
|
|
// initialize segment sizes to 0 in case they're not present
|
|
text.size = data.size = bss.size = 0;
|
|
|
|
for (int i = 0; i < ehdr.e_phnum; ++i) {
|
|
GElf_Phdr phdr;
|
|
if (gelf_getphdr(elf, i, &phdr) == 0) {
|
|
panic("gelf_getphdr failed for section %d", i);
|
|
}
|
|
|
|
// for now we don't care about non-loadable segments
|
|
if (!(phdr.p_type & PT_LOAD))
|
|
continue;
|
|
|
|
// the headers don't explicitly distinguish text from data,
|
|
// but empirically the text segment comes first.
|
|
if (text.size == 0) { // haven't seen text segment yet
|
|
text.baseAddr = phdr.p_vaddr;
|
|
text.size = phdr.p_filesz;
|
|
// remember where the data is for loadSections()
|
|
fileTextBits = fileData + phdr.p_offset;
|
|
// if there's any padding at the end that's not in the
|
|
// file, call it the bss. This happens in the "text"
|
|
// segment if there's only one loadable segment (as for
|
|
// kernel images).
|
|
bss.size = phdr.p_memsz - phdr.p_filesz;
|
|
bss.baseAddr = phdr.p_vaddr + phdr.p_filesz;
|
|
}
|
|
else if (data.size == 0) { // have text, this must be data
|
|
data.baseAddr = phdr.p_vaddr;
|
|
data.size = phdr.p_filesz;
|
|
// remember where the data is for loadSections()
|
|
fileDataBits = fileData + phdr.p_offset;
|
|
// if there's any padding at the end that's not in the
|
|
// file, call it the bss. Warn if this happens for both
|
|
// the text & data segments (should only have one bss).
|
|
if (phdr.p_memsz - phdr.p_filesz > 0 && bss.size != 0) {
|
|
warn("Two implied bss segments in file!\n");
|
|
}
|
|
bss.size = phdr.p_memsz - phdr.p_filesz;
|
|
bss.baseAddr = phdr.p_vaddr + phdr.p_filesz;
|
|
}
|
|
}
|
|
|
|
// should have found at least one loadable segment
|
|
assert(text.size != 0);
|
|
|
|
DPRINTFR(Loader, "text: 0x%x %d\ndata: 0x%x %d\nbss: 0x%x %d\n",
|
|
text.baseAddr, text.size, data.baseAddr, data.size,
|
|
bss.baseAddr, bss.size);
|
|
|
|
elf_end(elf);
|
|
|
|
// We will actually read the sections when we need to load them
|
|
}
|
|
|
|
|
|
bool
|
|
ElfObject::loadSections(FunctionalMemory *mem, bool loadPhys)
|
|
{
|
|
Addr textAddr = text.baseAddr;
|
|
Addr dataAddr = data.baseAddr;
|
|
|
|
if (loadPhys) {
|
|
textAddr &= (ULL(1) << 40) - 1;
|
|
dataAddr &= (ULL(1) << 40) - 1;
|
|
}
|
|
|
|
// Since we don't really have an MMU and all memory is
|
|
// zero-filled, there's no need to set up the BSS segment.
|
|
if (text.size != 0)
|
|
mem->prot_write(textAddr, fileTextBits, text.size);
|
|
if (data.size != 0)
|
|
mem->prot_write(dataAddr, fileDataBits, data.size);
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
bool
|
|
ElfObject::loadSomeSymbols(SymbolTable *symtab, int binding)
|
|
{
|
|
Elf *elf;
|
|
int secidx = 1; // there is a 0 but it is nothing, go figure
|
|
Elf_Scn *section;
|
|
GElf_Shdr shdr;
|
|
Elf_Data *data;
|
|
int count, ii;
|
|
bool found = false;
|
|
GElf_Sym sym;
|
|
|
|
if (!symtab)
|
|
return false;
|
|
|
|
// check that header matches library version
|
|
assert(elf_version(EV_CURRENT) != EV_NONE);
|
|
|
|
// get a pointer to elf structure
|
|
elf = elf_memory((char*)fileData,len);
|
|
|
|
assert(elf != NULL);
|
|
|
|
// Get the first section
|
|
section = elf_getscn(elf, secidx);
|
|
|
|
// While there are no more sections
|
|
while (section != NULL) {
|
|
gelf_getshdr(section, &shdr);
|
|
|
|
if (shdr.sh_type == SHT_SYMTAB) {
|
|
found = true;
|
|
data = elf_getdata(section, NULL);
|
|
count = shdr.sh_size / shdr.sh_entsize;
|
|
DPRINTF(Loader, "Found Symbol Table, %d symbols present\n", count);
|
|
|
|
// loop through all the symbols, only loading global ones
|
|
for (ii = 0; ii < count; ++ii) {
|
|
gelf_getsym(data, ii, &sym);
|
|
if (GELF_ST_BIND(sym.st_info) & binding) {
|
|
symtab->insert(sym.st_value,
|
|
elf_strptr(elf, shdr.sh_link, sym.st_name));
|
|
}
|
|
}
|
|
}
|
|
++secidx;
|
|
section = elf_getscn(elf, secidx);
|
|
}
|
|
|
|
elf_end(elf);
|
|
|
|
return found;
|
|
}
|
|
|
|
bool
|
|
ElfObject::loadGlobalSymbols(SymbolTable *symtab)
|
|
{
|
|
return loadSomeSymbols(symtab, STB_GLOBAL);
|
|
}
|
|
|
|
bool
|
|
ElfObject::loadLocalSymbols(SymbolTable *symtab)
|
|
{
|
|
return loadSomeSymbols(symtab, STB_LOCAL);
|
|
}
|