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Compress the compiled C code in the stub on lx_exec86 (saves 157 bytes).

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Also make 'fold_begin' processing more robust.
	p_lx_elf.cpp p_lx_sh.cpp p_unix.cpp
	stub/Makefile stub/l_lx_exec86.asm

committer: jreiser <jreiser> 958923851 +0000
This commit is contained in:
John Reiser
2000-05-21 15:44:11 +00:00
parent fdebd78d50
commit 6bb104b39f
5 changed files with 154 additions and 56 deletions
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src/p_unix.cpp
+30 -6
View File
@@ -426,10 +426,37 @@ void PackLinuxI386::patchLoader()
//patch_le32(loader,lsize,"UPX1",lsize); no longer used
patchVersion(loader,lsize);
Elf_LE32_Ehdr *const ehdr = (Elf_LE32_Ehdr *)(void *)loader;
Elf_LE32_Phdr *const phdr = (Elf_LE32_Phdr *)(1+ehdr);
// stub/scripts/setfold.pl puts address of 'fold_begin' in phdr[1].p_offset
off_t const fold_begin = phdr[1].p_offset;
MemBuffer cprLoader(lsize);
// compress compiled C-code portion of loader
upx_compress_config_t conf; memset(&conf, 0xff, sizeof(conf));
conf.c_flags = 0;
upx_uint result_buffer[16];
size_t const uncLsize = lsize - fold_begin;
size_t cprLsize;
upx_compress(
loader + fold_begin, uncLsize,
cprLoader, &cprLsize,
0, // progress_callback_t ??
getCompressionMethod(), 9,
&conf,
result_buffer
);
memcpy(fold_begin+loader, cprLoader, cprLsize);
lsize = fold_begin + cprLsize;
phdr->p_filesz = lsize;
// phdr->p_memsz is the decompressed size
// The beginning of our loader consists of a elf_hdr (52 bytes) and
// one section elf_phdr (32 byte) now,
// another section elf_phdr (32 byte) later, so we have 12 free bytes
// from offset 116 to the program start at offset 128.
// These 12 bytes are used for l_info by ::patchLoaderChecksum().
assert(get_le32(loader + 28) == 52); // e_phoff
assert(get_le32(loader + 32) == 0); // e_shoff
assert(get_le16(loader + 40) == 52); // e_ehsize
@@ -464,16 +491,13 @@ void PackLinuxI386::updateLoader(OutputFile *fo)
ehdr->e_phnum = 2;
// The first Phdr maps the stub (instructions, data, bss) rwx.
// Round up hi address to page boundary.
Elf_LE32_Phdr *phdro = (Elf_LE32_Phdr *)(sizeof(Elf_LE32_Ehdr)+loader);
unsigned const vaddr2 = PAGE_MASK & (~PAGE_MASK + phdro->p_memsz + phdro->p_vaddr);
// The second Phdr maps the overlay r--,
// to defend against /usr/bin/strip removing the overlay.
++phdro;
Elf_LE32_Phdr *const phdro = 1+(Elf_LE32_Phdr *)(1+ehdr);
phdro->p_type = PT_LOAD;
phdro->p_offset = lsize;
phdro->p_paddr = phdro->p_vaddr = vaddr2 + (lsize &~ PAGE_MASK);
phdro->p_paddr = phdro->p_vaddr = 0x00400000 + (lsize &~ PAGE_MASK);
phdro->p_memsz = phdro->p_filesz = fo->getBytesWritten() - lsize;
phdro->p_flags = PF_R;
phdro->p_align = -PAGE_MASK;