uint64_t elf_access_unsigned(struct elf_binary * elf, elf_ptrval base,
uint64_t moreoffset, size_t size)
{
elf_ptrval ptrval = base + moreoffset;
bool need_swap = elf_swap(elf);
const uint8_t *u8;
const uint16_t *u16;
const uint32_t *u32;
const uint64_t *u64;
if ( !elf_access_ok(elf, ptrval, size) )
return 0;
switch ( size )
{
case 1:
u8 = (const void*)ptrval;
return *u8;
case 2:
u16 = (const void*)ptrval;
return need_swap ? bswap_16(*u16) : *u16;
case 4:
u32 = (const void*)ptrval;
return need_swap ? bswap_32(*u32) : *u32;
case 8:
u64 = (const void*)ptrval;
return need_swap ? bswap_64(*u64) : *u64;
default:
return 0;
}
}
static elf_errorstatus xc_dom_load_elf_symtab(struct xc_dom_image *dom,
struct elf_binary *elf, bool load)
{
struct elf_binary syms;
ELF_HANDLE_DECL(elf_shdr) shdr; ELF_HANDLE_DECL(elf_shdr) shdr2;
xen_vaddr_t symtab, maxaddr;
elf_ptrval hdr;
size_t size;
unsigned h, count, type, i, tables = 0;
unsigned long *strtab_referenced = NULL;
if ( elf_swap(elf) )
{
DOMPRINTF("%s: non-native byte order, bsd symtab not supported",
__FUNCTION__);
return 0;
}
size = elf->bsd_symtab_pend - elf->bsd_symtab_pstart;
if ( load )
{
char *hdr_ptr;
size_t allow_size;
if ( !dom->bsd_symtab_start )
return 0;
hdr_ptr = xc_dom_vaddr_to_ptr(dom, dom->bsd_symtab_start, &allow_size);
if ( hdr_ptr == NULL )
{
DOMPRINTF("%s: xc_dom_vaddr_to_ptr(dom,dom->bsd_symtab_start"
" => NULL", __FUNCTION__);
return -1;
}
elf->caller_xdest_base = hdr_ptr;
elf->caller_xdest_size = allow_size;
hdr = ELF_REALPTR2PTRVAL(hdr_ptr);
elf_store_val(elf, unsigned, hdr, size - sizeof(unsigned));
}
else
{
static int xc_dom_load_elf_symtab(struct xc_dom_image *dom,
struct elf_binary *elf, int load)
{
struct elf_binary syms;
const elf_shdr *shdr, *shdr2;
xen_vaddr_t symtab, maxaddr;
char *hdr;
size_t size;
int h, count, type, i, tables = 0;
if ( elf_swap(elf) )
{
xc_dom_printf("%s: non-native byte order, bsd symtab not supported\n",
__FUNCTION__);
return 0;
}
if ( load )
{
if ( !dom->bsd_symtab_start )
return 0;
size = dom->kernel_seg.vend - dom->bsd_symtab_start;
hdr = xc_dom_vaddr_to_ptr(dom, dom->bsd_symtab_start);
*(int *)hdr = size - sizeof(int);
}
else
{
size = sizeof(int) + elf_size(elf, elf->ehdr) +
elf_shdr_count(elf) * elf_size(elf, shdr);
hdr = xc_dom_malloc(dom, size);
if ( hdr == NULL )
return 0;
dom->bsd_symtab_start = elf_round_up(&syms, dom->kernel_seg.vend);
}
memcpy(hdr + sizeof(int),
elf->image,
elf_size(elf, elf->ehdr));
memcpy(hdr + sizeof(int) + elf_size(elf, elf->ehdr),
elf->image + elf_uval(elf, elf->ehdr, e_shoff),
elf_shdr_count(elf) * elf_size(elf, shdr));
if ( elf_64bit(elf) )
{
Elf64_Ehdr *ehdr = (Elf64_Ehdr *)(hdr + sizeof(int));
ehdr->e_phoff = 0;
ehdr->e_phentsize = 0;
ehdr->e_phnum = 0;
ehdr->e_shoff = elf_size(elf, elf->ehdr);
ehdr->e_shstrndx = SHN_UNDEF;
}
else
{
Elf32_Ehdr *ehdr = (Elf32_Ehdr *)(hdr + sizeof(int));
ehdr->e_phoff = 0;
ehdr->e_phentsize = 0;
ehdr->e_phnum = 0;
ehdr->e_shoff = elf_size(elf, elf->ehdr);
ehdr->e_shstrndx = SHN_UNDEF;
}
if ( elf_init(&syms, hdr + sizeof(int), size - sizeof(int)) )
return -1;
if ( xc_dom_logfile )
elf_set_logfile(&syms, xc_dom_logfile, 1);
symtab = dom->bsd_symtab_start + sizeof(int);
maxaddr = elf_round_up(&syms, symtab + elf_size(&syms, syms.ehdr) +
elf_shdr_count(&syms) * elf_size(&syms, shdr));
xc_dom_printf("%s/%s: bsd_symtab_start=%" PRIx64 ", kernel.end=0x%" PRIx64
" -- symtab=0x%" PRIx64 ", maxaddr=0x%" PRIx64 "\n",
__FUNCTION__, load ? "load" : "parse",
dom->bsd_symtab_start, dom->kernel_seg.vend,
symtab, maxaddr);
count = elf_shdr_count(&syms);
for ( h = 0; h < count; h++ )
{
shdr = elf_shdr_by_index(&syms, h);
type = elf_uval(&syms, shdr, sh_type);
if ( type == SHT_STRTAB )
{
/* Look for a strtab @i linked to symtab @h. */
for ( i = 0; i < count; i++ )
{
shdr2 = elf_shdr_by_index(&syms, i);
if ( (elf_uval(&syms, shdr2, sh_type) == SHT_SYMTAB) &&
(elf_uval(&syms, shdr2, sh_link) == h) )
break;
}
/* Skip symtab @h if we found no corresponding strtab @i. */
if ( i == count )
{
if ( elf_64bit(&syms) )
*(Elf64_Off*)(&shdr->e64.sh_offset) = 0;
else
*(Elf32_Off*)(&shdr->e32.sh_offset) = 0;
continue;
}
}
if ( (type == SHT_STRTAB) || (type == SHT_SYMTAB) )
{
/* Mangled to be based on ELF header location. */
if ( elf_64bit(&syms) )
*(Elf64_Off*)(&shdr->e64.sh_offset) = maxaddr - symtab;
else
*(Elf32_Off*)(&shdr->e32.sh_offset) = maxaddr - symtab;
size = elf_uval(&syms, shdr, sh_size);
maxaddr = elf_round_up(&syms, maxaddr + size);
tables++;
xc_dom_printf("%s: h=%d %s, size=0x%zx, maxaddr=0x%" PRIx64 "\n",
__FUNCTION__, h,
type == SHT_SYMTAB ? "symtab" : "strtab",
size, maxaddr);
if ( load )
{
shdr2 = elf_shdr_by_index(elf, h);
memcpy((void*)elf_section_start(&syms, shdr),
elf_section_start(elf, shdr2),
size);
}
}
/* Name is NULL. */
if ( elf_64bit(&syms) )
*(Elf64_Half*)(&shdr->e64.sh_name) = 0;
else
*(Elf32_Word*)(&shdr->e32.sh_name) = 0;
}
if ( tables == 0 )
{
xc_dom_printf("%s: no symbol table present\n", __FUNCTION__);
dom->bsd_symtab_start = 0;
return 0;
}
if ( !load )
dom->kernel_seg.vend = maxaddr;
return 0;
}
