NixOS/patchelf
1
0
Fork 0
mirror of https://github.com/NixOS/patchelf.git synced 2025-10-21 14:50:50 +08:00
Code Issues Packages Projects Releases Wiki Activity

* Removed some duplicate code (and work around an apparent g++ code

Browse Source 
generation bug).
This commit is contained in:
Eelco Dolstra
2008-05-28 13:19:46 +00:00
parent dd00c21227
commit 656349fd15
1 changed files with 40 additions and 83 deletions
Download Patch File Download Diff File Expand all files Collapse all files

117
src/patchelf.cc
View File

@@ -118,6 +118,8 @@ public:
void rewriteSections();
void rewriteHeaders(Elf_Addr phdrAddress);
string getInterpreter();
void setInterpreter(const string & newInterpreter);
@@ -132,8 +134,24 @@ private:
specified by the ELF header) to this platform's integer
representation. */
template<class I>
I rdi(I i)
I rdi(I i);
/* Convert back to the ELF representation. */
template<class I>
I wri(I & t, unsigned long long i)
{
t = rdi(i);
return i;
}
};
/* !!! G++ creates broken code if this function is inlined, don't know
why... */
template<ElfFileParams>
template<class I>
I ElfFile<ElfFileParamNames>::rdi(I i)
{
I r = 0;
if (littleEndian) {
for (unsigned int n = 0; n < sizeof(I); ++n) {
@@ -145,16 +163,7 @@ private:
}
}
return r;
}
/* Convert back to the ELF representation. */
template<class I>
I wri(I & t, unsigned long long i)
{
t = rdi(i);
return i;
}
};
}
/* Some old versions of elf.h lack some required macros, so define
@@ -211,7 +220,7 @@ static void readFile(string fileName, mode_t * fileMode)
if (stat(fileName.c_str(), &st) != 0) error("stat");
fileSize = st.st_size;
*fileMode = st.st_mode;
maxSize = fileSize + 4 * 1024 * 1024;
maxSize = fileSize + 8 * 1024 * 1024;
contents = (unsigned char *) malloc(fileSize + maxSize);
if (!contents) abort();
@@ -473,13 +482,13 @@ void ElfFile<ElfFileParamNames>::rewriteSections()
sections at the end of the file. They're mapped into
memory by a PT_LOAD segment located directly after the last
virtual address page of other segments. */
Elf_Addr lastPage = 0;
Elf_Addr startPage = 0;
for (unsigned int i = 0; i < phdrs.size(); ++i) {
Elf_Addr thisPage = roundUp(rdi(phdrs[i].p_vaddr) + rdi(phdrs[i].p_memsz), pageSize);
if (thisPage > lastPage) lastPage = thisPage;
if (thisPage > startPage) startPage = thisPage;
}
debug("last page is 0x%llx\n", (unsigned long long) lastPage);
debug("last page is 0x%llx\n", (unsigned long long) startPage);
/* Compute the total space needed for the replaced sections
@@ -503,7 +512,7 @@ void ElfFile<ElfFileParamNames>::rewriteSections()
Elf_Phdr & phdr = phdrs[rdi(hdr->e_phnum) - 1];
wri(phdr.p_type, PT_LOAD);
wri(phdr.p_offset, startOffset);
wri(phdr.p_vaddr, wri(phdr.p_paddr, lastPage));
wri(phdr.p_vaddr, wri(phdr.p_paddr, startPage));
wri(phdr.p_filesz, wri(phdr.p_memsz, neededSpace));
wri(phdr.p_flags, PF_R | PF_W);
wri(phdr.p_align, 4096);
@@ -525,7 +534,7 @@ void ElfFile<ElfFileParamNames>::rewriteSections()
/* Update the section header for this section. */
wri(shdr.sh_offset, curOff);
wri(shdr.sh_addr, lastPage + (curOff - startOffset));
wri(shdr.sh_addr, startPage + (curOff - startOffset));
wri(shdr.sh_size, i->second.size());
wri(shdr.sh_addralign, sectionAlignment);
@@ -561,70 +570,10 @@ void ElfFile<ElfFileParamNames>::rewriteSections()
assert((off_t) curOff == startOffset + neededSpace);
/* !!! cut&paste */
/* Rewrite the program header table. */
/* Move the program header to the start of the new area. */
wri(hdr->e_phoff, startOffset);
/* If there is a segment for the program header table, update
it. (According to the ELF spec, it must be the first
entry.) */
if (rdi(phdrs[0].p_type) == PT_PHDR) {
phdrs[0].p_offset = hdr->e_phoff;
abort();
// !!! wri(phdrs[0].p_vaddr, wri(phdrs[0].p_paddr, firstPage + rdi(hdr->e_phoff)));
wri(phdrs[0].p_filesz, wri(phdrs[0].p_memsz, phdrs.size() * sizeof(Elf_Phdr)));
}
sortPhdrs();
for (unsigned int i = 0; i < phdrs.size(); ++i)
* ((Elf_Phdr *) (contents + rdi(hdr->e_phoff)) + i) = phdrs[i];
/* Rewrite the section header table. For neatness, keep the
sections sorted. */
assert(rdi(hdr->e_shnum) == shdrs.size());
sortShdrs();
for (unsigned int i = 1; i < rdi(hdr->e_shnum); ++i)
* ((Elf_Shdr *) (contents + rdi(hdr->e_shoff)) + i) = shdrs[i];
/* Update all those nasty virtual addresses in the .dynamic
section. */
Elf_Shdr & shdrDynamic = findSection(".dynamic");
Elf_Dyn * dyn = (Elf_Dyn *) (contents + rdi(shdrDynamic.sh_offset));
unsigned int d_tag;
for ( ; (d_tag = rdi(dyn->d_tag)) != DT_NULL; dyn++)
if (d_tag == DT_STRTAB)
dyn->d_un.d_ptr = findSection(".dynstr").sh_addr;
else if (d_tag == DT_STRSZ)
dyn->d_un.d_val = findSection(".dynstr").sh_size;
else if (d_tag == DT_SYMTAB)
dyn->d_un.d_ptr = findSection(".dynsym").sh_addr;
else if (d_tag == DT_HASH)
dyn->d_un.d_ptr = findSection(".hash").sh_addr;
else if (d_tag == DT_JMPREL) {
Elf_Shdr * shdr = findSection2(".rel.plt");
if (!shdr) shdr = findSection2(".rela.plt"); /* 64-bit Linux, x86-64 */
if (!shdr) shdr = findSection2(".rela.IA_64.pltoff"); /* 64-bit Linux, IA-64 */
if (!shdr) error("cannot find section corresponding to DT_JMPREL");
dyn->d_un.d_ptr = shdr->sh_addr;
}
else if (d_tag == DT_REL) { /* !!! hack! */
Elf_Shdr * shdr = findSection2(".rel.dyn");
/* no idea if this makes sense, but it was needed for some
program */
if (!shdr) shdr = findSection2(".rel.got");
if (!shdr) error("cannot find .rel.dyn or .rel.got");
dyn->d_un.d_ptr = shdr->sh_addr;
}
/* should probably update DT_RELA */
else if (d_tag == DT_VERNEED)
dyn->d_un.d_ptr = findSection(".gnu.version_r").sh_addr;
else if (d_tag == DT_VERSYM)
dyn->d_un.d_ptr = findSection(".gnu.version").sh_addr;
rewriteHeaders(startPage);
return;
}
@@ -778,13 +727,20 @@ void ElfFile<ElfFileParamNames>::rewriteSections()
assert((off_t) curOff == neededSpace);
rewriteHeaders(firstPage + rdi(hdr->e_phoff));
}
template<ElfFileParams>
void ElfFile<ElfFileParamNames>::rewriteHeaders(Elf_Addr phdrAddress)
{
/* Rewrite the program header table. */
/* If there is a segment for the program header table, update it.
(According to the ELF spec, it must be the first entry.) */
if (rdi(phdrs[0].p_type) == PT_PHDR) {
phdrs[0].p_offset = hdr->e_phoff;
wri(phdrs[0].p_vaddr, wri(phdrs[0].p_paddr, firstPage + rdi(hdr->e_phoff)));
wri(phdrs[0].p_vaddr, wri(phdrs[0].p_paddr, phdrAddress));
wri(phdrs[0].p_filesz, wri(phdrs[0].p_memsz, phdrs.size() * sizeof(Elf_Phdr)));
}
@@ -839,6 +795,7 @@ void ElfFile<ElfFileParamNames>::rewriteSections()
}
static void setSubstr(string & s, unsigned int pos, const string & t)
{
assert(pos + t.size() <= s.size());