+++ /dev/null
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-#include <libelfu/libelfu.h>
-
-
-static int appendData(ElfuScn *ms, void *buf, size_t len)
-{
- char *newbuf;
-
- assert(ms);
- assert(ms->shdr.sh_type != SHT_NOBITS);
- assert(ms->data.d_buf);
-
- newbuf = realloc(ms->data.d_buf, ms->shdr.sh_size + len);
- if (!newbuf) {
- ELFU_WARN("appendData: malloc() failed for newbuf.\n");
- return 1;
- }
-
- ms->data.d_buf = newbuf;
- memcpy(newbuf + ms->shdr.sh_size, buf, len);
- ms->shdr.sh_size += len;
- ms->data.d_size += len;
- assert(ms->shdr.sh_size == ms->data.d_size);
-
- return 0;
-}
-
-
-static ElfuScn* insertSection(ElfuElf *me, ElfuElf *mrel, ElfuScn *oldscn)
-{
- ElfuScn *newscn = NULL;
- GElf_Addr injAddr;
- GElf_Off injOffset;
- ElfuPhdr *injPhdr;
-
- if (oldscn->shdr.sh_flags & SHF_ALLOC) {
- newscn = elfu_mCloneScn(oldscn);
- if (!newscn) {
- return NULL;
- }
-
- if (newscn->shdr.sh_type == SHT_NOBITS) {
- /* Expand this to SHT_PROGBITS, then insert as such. */
-
- assert(!newscn->data.d_buf);
-
- newscn->data.d_buf = malloc(newscn->shdr.sh_size);
- if (!newscn->data.d_buf) {
- goto ERROR;
- }
- newscn->data.d_size = newscn->shdr.sh_size;
- newscn->shdr.sh_type = SHT_PROGBITS;
- }
-
- injAddr = elfu_mLayoutGetSpaceInPhdr(me,
- newscn->shdr.sh_size,
- newscn->shdr.sh_addralign,
- newscn->shdr.sh_flags & SHF_WRITE,
- newscn->shdr.sh_flags & SHF_EXECINSTR,
- &injPhdr);
-
- if (!injPhdr) {
- ELFU_WARN("insertSection: Could not find a place to insert section.\n");
- goto ERROR;
- }
-
- ELFU_INFO("Inserting %s at address 0x%x...\n",
- elfu_mScnName(mrel, oldscn),
- (unsigned)injAddr);
-
- injOffset = injAddr - injPhdr->phdr.p_vaddr + injPhdr->phdr.p_offset;
-
- newscn->shdr.sh_addr = injAddr;
- newscn->shdr.sh_offset = injOffset;
-
- if (CIRCLEQ_EMPTY(&injPhdr->childScnList)
- || CIRCLEQ_LAST(&injPhdr->childScnList)->shdr.sh_offset < injOffset) {
- CIRCLEQ_INSERT_TAIL(&injPhdr->childScnList, newscn, elemChildScn);
- } else {
- ElfuScn *ms;
- CIRCLEQ_FOREACH(ms, &injPhdr->childScnList, elemChildScn) {
- if (injOffset < ms->shdr.sh_offset) {
- CIRCLEQ_INSERT_BEFORE(&injPhdr->childScnList, ms, newscn, elemChildScn);
- break;
- }
- }
- }
-
-
- /* Inject name */
- if (me->shstrtab) {
- char *newname;
- size_t newnamelen;
-
- newnamelen = strlen("reladd") + 1;
- if (elfu_mScnName(mrel, oldscn)) {
- newnamelen += strlen(elfu_mScnName(mrel, oldscn));
- }
-
- newname = malloc(newnamelen);
- strcpy(newname, "reladd");
- strcat(newname, elfu_mScnName(mrel, oldscn));
-
- if (!newname) {
- ELFU_WARN("insertSection: malloc() failed for newname. Leaving section name empty.\n");
- newscn->shdr.sh_name = 0;
- } else {
- size_t offset = me->shstrtab->shdr.sh_size;
-
- if (!appendData(me->shstrtab, newname, newnamelen)) {
- newscn->shdr.sh_name = offset;
- }
-
- free(newname);
- }
- }
-
- return newscn;
- } else {
- ELFU_WARN("insertSection: Skipping non-memory section %s (type %d flags %u).\n",
- elfu_mScnName(mrel, oldscn),
- oldscn->shdr.sh_type,
- (unsigned)oldscn->shdr.sh_flags);
- goto ERROR;
- }
-
- ERROR:
- if (newscn) {
- // TODO: Destroy newscn
- }
- return NULL;
-}
-
-
-static void* subScnAdd1(ElfuElf *mrel, ElfuScn *ms, void *aux1, void *aux2)
-{
- ElfuScn *newscn;
- ElfuElf *me = (ElfuElf*)aux1;
- (void)aux2;
-
-
- switch(ms->shdr.sh_type) {
- case SHT_PROGBITS: /* 1 */
- case SHT_NOBITS: /* 8 */
- /* Ignore empty sections */
- if (ms->shdr.sh_size == 0) {
- break;
- }
-
- /* Find a place where it belongs and shove it in. */
- newscn = insertSection(me, mrel, ms);
- if (!newscn) {
- ELFU_WARN("mReladd: Could not insert section %s (type %d), skipping.\n",
- elfu_mScnName(mrel, ms),
- ms->shdr.sh_type);
- }
- break;
- }
-
- return NULL;
-}
-
-
-static void* subScnAdd2(ElfuElf *mrel, ElfuScn *ms, void *aux1, void *aux2)
-{
- ElfuElf *me = (ElfuElf*)aux1;
- (void)aux2;
-
- switch(ms->shdr.sh_type) {
- case SHT_NULL: /* 0 */
- case SHT_PROGBITS: /* 1 */
- case SHT_STRTAB: /* 3 */
- case SHT_NOBITS: /* 8 */
- break;
-
-
- case SHT_REL: /* 9 */
- /* Relocate. */
- elfu_mRelocate(me, elfu_mScnByOldscn(me, ms->infoptr), ms);
- break;
-
- case SHT_RELA: /* 4 */
- // TODO: Needs a parser
- //elfu_mRelocate(elfu_mScnByOldscn(me, ms->infoptr), ms);
-
- case SHT_SYMTAB: /* 2 */
- /* Merge with the existing table. Take care of string tables also. */
-
- /* The next section types either do not occur in .o files, or are
- * not strictly necessary to process here. */
- case SHT_NOTE: /* 7 */
- case SHT_HASH: /* 5 */
- case SHT_DYNAMIC: /* 6 */
- case SHT_SHLIB: /* 10 */
- case SHT_DYNSYM: /* 11 */
- case SHT_INIT_ARRAY: /* 14 */
- case SHT_FINI_ARRAY: /* 15 */
- case SHT_PREINIT_ARRAY: /* 16 */
- case SHT_GROUP: /* 17 */
- case SHT_SYMTAB_SHNDX: /* 18 */
- case SHT_NUM: /* 19 */
- default:
- ELFU_WARN("mReladd: Skipping section %s (type %d).\n",
- elfu_mScnName(mrel, ms),
- ms->shdr.sh_type);
- }
-
- return NULL;
-}
-
-
-
-static void insertSymClone(ElfuElf *me, const ElfuScn *oldmsst, const ElfuSym *oldsym)
-{
- GElf_Xword newsize;
- char *newbuf;
- ElfuScn *newscn = NULL;
- ElfuSym *newsym;
- char *oldsymname;
-
- assert(me);
- assert(oldmsst);
- assert(oldsym);
-
- /* If the old symbol pointed to a section, find its clone in the target */
- if (oldsym->scnptr) {
- newscn = elfu_mScnByOldscn(me, oldsym->scnptr);
-
- /* If we didn't copy the section referenced, we won't
- * copy this symbol either */
- if (!newscn) {
- return;
- }
- }
-
- // TODO: Allocate symtab if none present
- assert(me->symtab);
-
- /* Allocate memory for the cloned symbol */
- newsym = malloc(sizeof(*newsym));
- if (!newsym) {
- ELFU_WARN("insertSymClone: malloc() failed for newsym.\n");
- goto ERROR;
- }
-
- oldsymname = ELFU_SYMSTR(oldmsst, oldsym->name);
-
- /* Expand .strtab, append symbol name, link newsym to it */
- newsize = me->symtab->linkptr->shdr.sh_size + strlen(oldsymname) + 1;
- newbuf = realloc(me->symtab->linkptr->data.d_buf, newsize);
- if (!newbuf) {
- ELFU_WARN("insertSymClone: realloc() failed for strtab.\n");
- goto ERROR;
- }
-
- me->symtab->linkptr->data.d_buf = newbuf;
-
- newsym->name = me->symtab->linkptr->shdr.sh_size;
-
- strcpy(newbuf + newsym->name, oldsymname);
-
- me->symtab->linkptr->data.d_size = newsize;
- me->symtab->linkptr->shdr.sh_size = newsize;
-
-
- /* Copy all other fields */
- newsym->scnptr = newscn;
- newsym->shndx = oldsym->shndx; /* If scnptr == NULL, this becomes relevant */
- newsym->bind = oldsym->bind;
- newsym->other = oldsym->other;
- newsym->size = oldsym->size;
- newsym->type = oldsym->type;
- newsym->value = oldsym->value;
-
- /* In executables, symbol addresses need to be in memory */
- if (newscn) {
- newsym->value += newscn->shdr.sh_addr;
- }
-
- /* Insert symbol */
- CIRCLEQ_INSERT_TAIL(&me->symtab->symtab.syms, newsym, elem);
-
- return;
-
- ERROR:
- if (newsym) {
- free(newsym);
- }
-}
-
-static void mergeSymtab(ElfuElf *me, const ElfuElf *mrel)
-{
- ElfuSym *sym;
-
- assert(me);
- assert(mrel);
-
- CIRCLEQ_FOREACH(sym, &mrel->symtab->symtab.syms, elem) {
- insertSymClone(me, mrel->symtab, sym);
- }
-}
-
-
-
-void elfu_mReladd(ElfuElf *me, const ElfuElf *mrel)
-{
- assert(me);
- assert(mrel);
-
- /* For each section in object file, guess how to insert it */
- elfu_mScnForall((ElfuElf*)mrel, subScnAdd1, me, NULL);
-
- mergeSymtab(me, mrel);
-
- /* Do relocations and other stuff */
- elfu_mScnForall((ElfuElf*)mrel, subScnAdd2, me, NULL);
-
- /* Re-layout to accommodate new contents */
- elfu_mLayoutAuto(me);
-}
projects / centaur.git / blobdiff