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#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <libelf/libelf.h>
#include <libelf/gelf.h>
#include <libelfu/libelfu.h>
static ElfuPhdr* modelFromPhdr(GElf_Phdr *phdr)
{
ElfuPhdr *mp;
assert(phdr);
mp = malloc(sizeof(ElfuPhdr));
if (!mp) {
ELFU_WARN("modelFromPhdr: malloc() failed for ElfuPhdr.\n");
return NULL;
}
mp->phdr = *phdr;
return mp;
}
static ElfuScn* modelFromSection(Elf_Scn *scn)
{
ElfuScn *ms;
assert(scn);
ms = malloc(sizeof(ElfuScn));
if (!ms) {
ELFU_WARN("modelFromSection: malloc() failed for ElfuScn.\n");
goto ERROR;
}
assert(gelf_getshdr(scn, &ms->shdr) == &ms->shdr);
/* Copy each data part in source segment */
ms->data.d_align = 1;
ms->data.d_buf = NULL;
ms->data.d_off = 0;
ms->data.d_type = ELF_T_BYTE;
ms->data.d_size = ms->shdr.sh_size;
ms->data.d_version = elf_version(EV_NONE);
if (ms->shdr.sh_type != SHT_NOBITS
&& ms->shdr.sh_size > 0) {
Elf_Data *data;
ms->data.d_buf = malloc(ms->shdr.sh_size);
if (!ms->data.d_buf) {
ELFU_WARN("modelFromSection: malloc() failed for data buffer (%jx bytes).\n", ms->shdr.sh_size);
goto ERROR;
}
/* A non-empty section should contain at least one data block. */
data = elf_rawdata(scn, NULL);
assert(data);
ms->data.d_align = data->d_align;
ms->data.d_type = data->d_type;
ms->data.d_version = data->d_version;
while (data) {
if (data->d_off + data->d_size > ms->shdr.sh_size) {
ELFU_WARN("modelFromSection: libelf delivered a bogus data blob. Skipping\n");
} else {
memcpy(ms->data.d_buf + data->d_off, data->d_buf, data->d_size);
}
data = elf_rawdata(scn, data);
}
}
return ms;
ERROR:
if (ms) {
free(ms);
}
return NULL;
}
ElfuElf* elfu_mFromElf(Elf *e)
{
ElfuElf *me;
size_t shstrndx;
size_t i, numPhdr, numShdr;
assert(e);
if (elfu_eCheck(e)) {
goto ERROR;
}
me = malloc(sizeof(ElfuElf));
if (!me) {
ELFU_WARN("elfu_mFromElf: malloc() failed for ElfuElf.\n");
goto ERROR;
}
/* General stuff */
CIRCLEQ_INIT(&me->scnList);
CIRCLEQ_INIT(&me->phdrList);
me->shstrtab = NULL;
me->elfclass = gelf_getclass(e);
assert(me->elfclass != ELFCLASSNONE);
assert(gelf_getehdr(e, &me->ehdr) == &me->ehdr);
/* Get the section string table index */
if (elf_getshdrstrndx(e, &shstrndx) != 0) {
shstrndx = 0;
}
/* Load segments */
assert(!elf_getphdrnum(e, &numPhdr));
for (i = 0; i < numPhdr; i++) {
GElf_Phdr phdr;
ElfuPhdr *mp;
assert(gelf_getphdr(e, i, &phdr) == &phdr);
mp = modelFromPhdr(&phdr);
if (!mp) {
goto ERROR;
}
CIRCLEQ_INSERT_TAIL(&me->phdrList, mp, elem);
}
/* Load sections */
assert(!elf_getshdrnum(e, &numShdr));
for (i = 1; i < numShdr; i++) {
Elf_Scn *scn;
ElfuScn *ms;
scn = elf_getscn(e, i);
assert(scn);
ms = modelFromSection(scn);
if (!ms) {
goto ERROR;
}
CIRCLEQ_INSERT_TAIL(&me->scnList, ms, elem);
if (i == shstrndx) {
me->shstrtab = ms;
}
}
/* Find sh_link dependencies */
/* Sort sections by offset */
/* Find PHDR -> Section dependencies */
return me;
ERROR:
if (me) {
// TODO: Free data structures
}
ELFU_WARN("elfu_mFromElf: Failed to load file.\n");
return NULL;
}
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