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-rw-r--r--src/model/insert.c289
1 files changed, 0 insertions, 289 deletions
diff --git a/src/model/insert.c b/src/model/insert.c
deleted file mode 100644
index b18aa8a..0000000
--- a/src/model/insert.c
+++ /dev/null
@@ -1,289 +0,0 @@
-#include <assert.h>
-#include <sys/types.h>
-#include <libelf/gelf.h>
-#include <libelfu/libelfu.h>
-
-
-// TODO: Take p_align into account
-
-
-
-/*
- * Insert space at a given position in the file by moving everything
- * after it towards the end of the file, and everything before it
- * towards lower memory regions where it is mapped.
- *
- * off must not be in the middle of any data structure, such as
- * PHDRs, SHDRs, or sections. Behaviour is undefined if it is.
- *
- * PHDRs will be patched such that everything AFTER off is mapped to
- * the same address in memory, and everything BEFORE it is shifted to
- * lower addresses, making space for the new data in-between.
- */
-GElf_Xword elfu_mInsertSpaceBefore(ElfuElf *me, GElf_Off off, GElf_Xword size)
-{
- ElfuScn *ms;
- ElfuPhdr *mp;
-
- assert(me);
-
- /* Round up size to 4096 bytes to keep page alignment on x86 when
- * remapping existing data to lower addresses. */
- size += (4096 - (size % 4096)) % 4096;
- // TODO: Find alignment size by checking p_align in PHDRs
-
- /* Move SHDRs and PHDRs */
- if (me->ehdr.e_shoff >= off) {
- me->ehdr.e_shoff += size;
- }
-
- if (me->ehdr.e_phoff >= off) {
- me->ehdr.e_phoff += size;
- }
-
- /* Patch PHDRs to include new data */
- CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
- GElf_Off end = mp->phdr.p_offset + mp->phdr.p_filesz;
-
- if (mp->phdr.p_offset >= off) {
- /* Insertion before PHDR's content, so it's just shifted */
- mp->phdr.p_offset += size;
- } else {
- /* mp->phdr.p_offset < off */
-
- if (off < end) {
- /* Insertion in the middle of PHDR, so let it span the new data */
- mp->phdr.p_filesz += size;
- mp->phdr.p_memsz += size;
- mp->phdr.p_vaddr -= size;
- mp->phdr.p_paddr -= size;
- } else {
- /* Insertion after PHDR's content, so it may need to be
- remapped. This will happen in a second pass.
- */
- }
- }
- }
-
- /* For each LOAD header, find clashing headers that need to be
- remapped to lower memory areas.
- */
- CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
- if (mp->phdr.p_type == PT_LOAD) {
- ElfuPhdr *mp2;
-
- CIRCLEQ_FOREACH(mp2, &me->phdrList, elem) {
- if (mp2->phdr.p_type != PT_LOAD
- && mp2->phdr.p_offset + mp2->phdr.p_filesz <= off) {
- /* The PHDR ends in the file before the injection site */
- GElf_Off vend1 = mp->phdr.p_vaddr + mp->phdr.p_memsz;
- GElf_Off pend1 = mp->phdr.p_paddr + mp->phdr.p_memsz;
- GElf_Off vend2 = mp2->phdr.p_vaddr + mp2->phdr.p_memsz;
- GElf_Off pend2 = mp2->phdr.p_paddr + mp2->phdr.p_memsz;
-
- /* If mp and mp2 now overlap in memory */
- if ((mp2->phdr.p_vaddr < vend1 && vend2 > mp->phdr.p_vaddr)
- || (mp2->phdr.p_paddr < pend1 && pend2 > mp->phdr.p_paddr)) {
- /* Move mp2 down in memory, as mp has been resized.
- Maintaining the relative offset between them is the best
- guess at maintaining consistency.
- */
- mp2->phdr.p_vaddr -= size;
- mp2->phdr.p_paddr -= size;
- }
- }
- }
- }
- }
-
- /* Move the sections themselves */
- CIRCLEQ_FOREACH(ms, &me->scnList, elem) {
- if (ms->shdr.sh_offset >= off) {
- ms->shdr.sh_offset += size;
- } else {
- /* sh_offset < off */
-
- /* If this was in a LOAD segment, it has been adjusted there
- and this synchronises it.
- If not, it doesn't matter anyway.
- */
- ms->shdr.sh_addr -= size;
- }
- }
-
- return size;
-}
-
-
-
-/*
- * Insert space at a given position in the file by moving everything
- * after it towards the end of the file, and towards higher memory
- * regions where it is mapped.
- *
- * off must not be in the middle of any data structure, such as
- * PHDRs, SHDRs, or sections. Behaviour is undefined if it is.
- *
- * PHDRs will be patched such that everything AFTER off is shifted to
- * higher addresses, making space for the new data in-between.
- *
- * CAUTION: This also moves NOBITS sections. If such are present,
- * use mExpandNobits() first and then inject at the end of
- * the expansion site.
- */
-GElf_Xword elfu_mInsertSpaceAfter(ElfuElf *me, GElf_Off off, GElf_Xword size)
-{
- ElfuScn *ms;
- ElfuPhdr *mp;
-
- assert(me);
-
-/* Move SHDRs and PHDRs */
- if (me->ehdr.e_shoff >= off) {
- me->ehdr.e_shoff += size;
- }
-
- if (me->ehdr.e_phoff >= off) {
- me->ehdr.e_phoff += size;
- }
-
- /* Patch PHDRs to include new data */
- CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
- GElf_Off end = mp->phdr.p_offset + mp->phdr.p_filesz;
-
- if (mp->phdr.p_offset >= off) {
- /* Insertion before PHDR's content, so it's shifted. */
- mp->phdr.p_offset += size;
-
- /* It may also need to be remapped. See second pass below. */
- } else {
- /* mp->phdr.p_offset < off */
-
- if (off < end) {
- /* Insertion in the middle of PHDR, so let it span the new data */
- mp->phdr.p_filesz += size;
- mp->phdr.p_memsz += size;
- } else {
- /* Insertion after PHDR's content. Nothing to do. */
- }
- }
- }
-
- /* For each LOAD header, find clashing headers that need to be
- remapped to higher memory areas.
- */
- CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
- if (mp->phdr.p_type == PT_LOAD) {
- ElfuPhdr *mp2;
-
- CIRCLEQ_FOREACH(mp2, &me->phdrList, elem) {
- if (mp2->phdr.p_type != PT_LOAD
- && mp2->phdr.p_offset + mp2->phdr.p_filesz > off) {
- /* The PHDR now ends in the file after the injection site */
- GElf_Off vend1 = mp->phdr.p_vaddr + mp->phdr.p_memsz;
- GElf_Off pend1 = mp->phdr.p_paddr + mp->phdr.p_memsz;
- GElf_Off vend2 = mp2->phdr.p_vaddr + mp2->phdr.p_memsz;
- GElf_Off pend2 = mp2->phdr.p_paddr + mp2->phdr.p_memsz;
-
- /* If mp and mp2 now overlap in memory */
- if ((mp2->phdr.p_vaddr < vend1 && vend2 > mp->phdr.p_vaddr)
- || (mp2->phdr.p_paddr < pend1 && pend2 > mp->phdr.p_paddr)) {
- /* Move mp2 up in memory, as mp has been resized.
- Maintaining the relative offset between them is the best
- guess at maintaining consistency.
- */
-
- mp2->phdr.p_vaddr += size;
- mp2->phdr.p_paddr += size;
- }
- }
- }
- }
- }
-
- /* Move the sections themselves */
- CIRCLEQ_FOREACH(ms, &me->scnList, elem) {
- if (ms->shdr.sh_offset >= off) {
- ms->shdr.sh_offset += size;
-
- /* If this was in a LOAD segment, it has been adjusted there
- and this synchronises it.
- If not, it doesn't matter anyway.
- */
- ms->shdr.sh_addr += size;
- }
- }
-
- return size;
-}
-
-
-
-
-
-/* Update cross-references */
-static void shiftSections(ElfuElf *me, ElfuScn *first)
-{
- ElfuScn *ms = first;
- size_t firstIndex = elfu_mScnIndex(me, first);
-
- do {
- if (ms == me->shstrtab) {
- me->ehdr.e_shstrndx++;
- }
-
- ms = CIRCLEQ_LOOP_NEXT(&me->scnList, ms, elem);
- } while (ms != CIRCLEQ_FIRST(&me->scnList));
-
- CIRCLEQ_FOREACH(ms, &me->scnList, elem) {
- switch (ms->shdr.sh_type) {
- case SHT_REL:
- case SHT_RELA:
- if (ms->shdr.sh_info >= firstIndex) {
- ms->shdr.sh_info++;
- }
- case SHT_DYNAMIC:
- case SHT_HASH:
- case SHT_SYMTAB:
- case SHT_DYNSYM:
- case SHT_GNU_versym:
- case SHT_GNU_verdef:
- case SHT_GNU_verneed:
- if (ms->shdr.sh_link >= firstIndex) {
- ms->shdr.sh_link++;
- }
- }
- }
-}
-
-
-/*
- * Insert a section into an ELF model, /before/ a given other section
- */
-void elfu_mInsertScnInChainBefore(ElfuElf *me, ElfuScn *oldscn, ElfuScn *newscn)
-{
- assert(me);
- assert(oldscn);
- assert(newscn);
-
- shiftSections(me, oldscn);
-
- CIRCLEQ_INSERT_BEFORE(&me->scnList, oldscn, newscn, elem);
-}
-
-
-/*
- * Insert a section into an ELF model, /after/ a given other section
- */
-void elfu_mInsertScnInChainAfter(ElfuElf *me, ElfuScn *oldscn, ElfuScn *newscn)
-{
- assert(me);
- assert(oldscn);
- assert(newscn);
-
- if (oldscn != CIRCLEQ_LAST(&me->scnList)) {
- shiftSections(me, CIRCLEQ_NEXT(oldscn, elem));
- }
-
- CIRCLEQ_INSERT_AFTER(&me->scnList, oldscn, newscn, elem);
-}
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