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/* datahandler.c - burneye2 .rodata/.data handling functions
*
* by scut
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <elf.h>
#include <common.h>
#include <utility.h>
#include <elf_reloc.h>
#include <elf_section.h>
#include <datahandler.h>
data_item *
dh_item_new (void)
{
return (xcalloc (1, sizeof (data_item)));
}
data_item *
dh_item_list_create_bysymreloc (elf_base *base, elf_section *datasec,
elf_rel_list *rel)
{
unsigned int n,
sym_size;
data_item * dh = dh_item_new ();
/* start with a section-sized item that is dangling, then carve the
* used space out of it incrementally
*/
dh->dangling = 1;
dh->offset = 0;
dh->length = datasec->Shdr.sh_size;
/* first carve the 100% known symbol table entries
*/
sym_size = base->symtab->data_len / sizeof (Elf32_Sym);
for (n = 0 ; n < sym_size ; ++n) {
elf_symbol * sym;
sym = elf_sym_fetch_byindex (base, n);
assert (sym != NULL);
if (sym->sec == NULL || sym->sec->sh_idx != datasec->sh_idx) {
free (sym);
continue;
}
fnote ("item: %s\n", sym->name);
if (sym->sent.st_size == 0) {
fnote (" size is zero, skipping.\n");
continue;
}
assert (sym->sent.st_value < datasec->data_len);
dh = dh_carve (dh, sym->sent.st_value, sym->sent.st_size,
&datasec->data[sym->sent.st_value]);
assert (dh != NULL);
}
#if 0
/* search for correct relocation frame in list
*/
while (rel != NULL) {
if (rel->reloc_modify->sh_idx == datasec->sh_idx)
break;
rel = rel->next;
}
for (n = 0 ; n < rel->reloc_count ; ++n) {
}
#endif
return (dh);
}
data_item *
dh_carve (data_item *dh, unsigned int offset, unsigned int length,
unsigned char *data)
{
data_item * ret = dh;
data_item * wlk;
data_item * wlk_last = NULL;
data_item * new;
for (wlk = dh ; wlk != NULL ; wlk = wlk->next) {
/* ignore space already given to someone else or blocks that
* do not cover our range
*/
if (wlk->dangling == 0 ||
(wlk->offset + wlk->length) < (offset + length))
{
wlk_last = wlk;
continue;
}
/* since we know the list is ordered we can safely abort once
* we are past our offset
*/
if (wlk->offset > offset)
break;
/* now we've found the block we have to cut
*/
if (wlk->offset < offset) {
data_item * nbf = dh_item_new ();
nbf->offset = wlk->offset;
nbf->length = offset - wlk->offset;
nbf->dangling = 1;
nbf->data = wlk->data;
nbf->next = wlk;
if (wlk_last == NULL)
ret = nbf;
else
wlk_last->next = nbf;
wlk_last = nbf;
wlk->offset += nbf->length;
wlk->length -= nbf->length;
wlk->data += nbf->length;
}
assert (wlk->offset == offset);
new = dh_item_new ();
new->next = wlk;
new->offset = offset;
new->length = length;
new->data = wlk->data;
wlk->length -= length;
wlk->offset = offset + length;
wlk->data += length;
if (wlk->length == 0) {
new->next = wlk->next;
free (wlk);
}
if (wlk_last == NULL)
ret = new;
else
wlk_last->next = new;
return (ret);
}
return (NULL);
}
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