static const value_t *
elf_get_phdrs(const value_t *this_fn, parser_state_t *state,
const char *filename, int binfd,
Elf *e, GElf_Ehdr *ehdr, void *arg)
{
const value_t *resval = NULL;
size_t n;
if (elf_getphdrnum(e, &n) != 0)
parser_report(state, "ELF file has unknown number of segments - %s\n",
elf_errmsg(-1));
else {
size_t i;
dir_t *partdir = dir_vec_new();
for (i = 0; i < n; i++) {
GElf_Phdr phdr;
dir_t *pdir = dir_id_new();
if (gelf_getphdr(e, i, &phdr) != &phdr)
parser_report(state,
"ELF segment %d unretrievable - %s\n",
i, elf_errmsg(-1));
else {
dir_string_set(pdir,"type" , value_int_new(phdr.p_type));
dir_string_set(pdir,"offset" , value_int_new(phdr.p_offset));
dir_string_set(pdir,"vaddr" , value_int_new(phdr.p_vaddr));
dir_string_set(pdir,"paddr" , value_int_new(phdr.p_paddr));
dir_string_set(pdir,"filesz" , value_int_new(phdr.p_filesz));
dir_string_set(pdir,"memsz" , value_int_new(phdr.p_memsz));
dir_string_set(pdir,"flags" , value_int_new(phdr.p_flags));
dir_string_set(pdir,"align" , value_int_new(phdr.p_align));
dir_int_set(partdir, i, dir_value(pdir));
}
}
resval = dir_value(partdir);
}
return resval;
}
extern bool FTL_EXTENSION_MAIN(parser_state_t *state, dir_t *cmds)
{
mod_add_val(cmds, "version", value_int_new(42));
}
/* Invoke the argument FTL function with <addr> <buf> arguments for each of
the ELF file's program segments */
static const value_t *
elf_load_with_fn(const value_t *this_fn, parser_state_t *state,
const char *filename, int binfd,
Elf *e, GElf_Ehdr *ehdr, void *arg)
{
elf_loadfn_args_t *fnarg = (elf_loadfn_args_t *)arg;
const value_t *hdrcheckfn = fnarg->hdrcheckfn;
const value_t *memwrfn = fnarg->memwrfn;
const value_t *resval = value_false;
size_t n;
if (elf_getphdrnum(e, &n) != 0)
parser_report(state, "ELF file has unknown number of segments - %s\n",
elf_errmsg(-1));
else {
size_t i;
bool ok = FALSE;
if (hdrcheckfn != NULL) {
const value_t *ehdrval = elf_get_ehdr(this_fn, state, filename, binfd,
e, ehdr, /*arg*/NULL);
if (ehdrval != NULL) {
const value_t *code = value_closure_bind(hdrcheckfn, ehdrval);
if (code == NULL) {
parser_error(state, "couldn't apply "
"header argument to check function\n");
} else {
const value_t *fnres = invoke(code, state);
/* we expect this to return a TRUE/FALSE value */
ok = (fnres == value_true);
/*if (!ok) printf("%s: check fn returns non-TRUE\n", codeid());*/
}
}
} else
ok = TRUE;
resval = ok? value_true: value_false;
if (ok && memwrfn != NULL) {
for (i = 0; ok && i < n; i++) {
GElf_Phdr phdr;
if (gelf_getphdr(e, i, &phdr) != &phdr)
parser_report(state, "ELF segment %d unretrievable - %s\n",
i, elf_errmsg(-1));
else {
long offset = (long)phdr.p_offset;
if (phdr.p_offset != (Elf64_Off)offset)
parser_report(state, "ELF segment %d - "
"offset does not fit in 32-bits\n", i);
else
if (-1 == fe_lseek(binfd, offset))
parser_report(state, "ELF segment %d - "
"offset 0X%lX is outside file\n",
i, offset);
else
if (phdr.p_memsz < phdr.p_filesz)
parser_report(state,
"ELF segment %d - smaller size in memory (%d)"
"than on file (%d) - corrupt header?\n",
i, phdr.p_memsz, phdr.p_filesz);
else {
number_t addr = phdr.p_vaddr; /* where to load segment */
char *buf = NULL;
size_t buflen = (size_t)phdr.p_memsz;
value_t *addrval = value_int_new(addr);
value_t *dataval = value_string_alloc_new(buflen, &buf);
if (phdr.p_memsz != (Elf64_Xword)buflen)
parser_report(state, "ELF segment %d - "
"size does not fit in 32-bits\n", i);
else
if (dataval == NULL)
parser_report(state,
"ELF segment %d - no memory for "
"next %d bytes\n",
i, buflen);
else {
ssize_t readbytes = fe_read(binfd, buf, buflen);
if (readbytes < buflen)
parser_report(state,
"ELF segment %d - "
"only %d bytes of %d read\n",
i, readbytes);
else {
const value_t *code;
ok = TRUE;
/* zero any uninitialized area */
if (phdr.p_memsz > phdr.p_filesz) {
size_t extra_bytes = (size_t)
(phdr.p_memsz - phdr.p_filesz);
if ((Elf64_Xword)extra_bytes !=
phdr.p_memsz-phdr.p_filesz) {
ok = FALSE;
parser_report(state, "ELF segment %d - "
"BSS area larger than 32-bits\n",
i);
} else
memset(&buf[phdr.p_filesz], '\0', extra_bytes);
}
code = value_closure_bind_2(state, memwrfn,
"address", addrval,
"data", dataval);
if (NULL != code) {
const value_t *fnres = invoke(code, state);
/* we expect this to return a TRUE/FALSE value */
if (fnres != value_true) {
/*printf("%s: seg fn returns non-TRUE\n",
codeid());*/
ok = FALSE;
}
/* we rely on garbage collection to collect the data
* buffer */
} else
value_delete(&dataval);
}
}
}
}
}
if (!ok)
resval = value_false;
}
}
return resval;
}
static const value_t *
elf_get_ehdr(const value_t *this_fn, parser_state_t *state,
const char *filename, int binfd,
Elf *e, GElf_Ehdr *ehdr, void *arg)
{
int eclass = gelf_getclass(e);
char *id = elf_getident(e, NULL);
dir_t *einfo = dir_id_new();
dir_t *edir = dir_id_new();
size_t n;
if (eclass == ELFCLASS32)
dir_string_set(einfo, "class", value_int_new(32));
else if (eclass == ELFCLASS64)
dir_string_set(einfo, "class", value_int_new(64));
else {
dir_string_set(einfo, "class", &value_null);
if (eclass != ELFCLASSNONE)
parser_report(state, "ELF file has unknown class %d - %s\n",
eclass, elf_errmsg(-1));
}
if (id == NULL)
parser_report(state, "ELF file has unknown identity - %s\n",
elf_errmsg(-1));
else
dir_string_set(einfo, "id",
value_string_new(id, EI_NIDENT));
dir_string_set(einfo, "ehdr", dir_value(edir));
dir_string_set(edir,"type" , value_int_new(ehdr->e_type));
dir_string_set(edir,"machine", value_int_new(ehdr->e_machine));
dir_string_set(edir,"version", value_int_new(ehdr->e_version));
dir_string_set(edir,"entry" , value_int_new(ehdr->e_entry));
dir_string_set(edir,"phoff" , value_int_new(ehdr->e_phoff));
dir_string_set(edir,"shoff" , value_int_new(ehdr->e_shoff));
dir_string_set(edir,"flags" , value_int_new(ehdr->e_flags));
dir_string_set(edir,"ehsize" , value_int_new(ehdr->e_ehsize));
dir_string_set(edir,"phentsize",
value_int_new(ehdr->e_phentsize));
dir_string_set(edir,"shentsize",
value_int_new(ehdr->e_shentsize));
if (elf_getphdrnum(e, &n) != 0)
parser_report(state,"ELF file has unknown number of segments - %s\n",
elf_errmsg(-1));
else
dir_string_set(einfo, "progsects", value_int_new(n));
if (elf_getshdrnum(e, &n) != 0)
parser_report(state, "%s: ELF file has unknown number of sections - %s\n",
elf_errmsg(-1));
else
dir_string_set(einfo, "sections", value_int_new(n));
if (elf_getshdrstrndx(e, &n) != 0)
parser_report(state, "%s: ELF file has no section names - %s\n",
elf_errmsg(-1));
else
dir_string_set(einfo, "shdrstrndx", value_int_new(n));
return dir_value(einfo);
}
