/* dl.c - arch-dependent part of loadable module support */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2002,2004,2005,2007,2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/dl.h>
#include <grub/elf.h>
#include <grub/misc.h>
#include <grub/err.h>
#include <grub/mm.h>
/* Check if EHDR is a valid ELF header. */
grub_err_t
grub_arch_dl_check_header (void *ehdr)
{
Elf_Ehdr *e = ehdr;
/* Check the magic numbers. */
if (e->e_ident[EI_CLASS] != ELFCLASS64
|| e->e_ident[EI_DATA] != ELFDATA2LSB
|| e->e_machine != EM_IA_64)
return grub_error (GRUB_ERR_BAD_OS, "invalid arch specific ELF magic");
return GRUB_ERR_NONE;
}
#define MASK20 ((1 << 20) - 1)
#define MASK19 ((1 << 19) - 1)
struct unaligned_uint32
{
grub_uint32_t val;
} __attribute__ ((packed));
static void
add_value_to_slot_20b (grub_addr_t addr, grub_uint32_t value)
{
struct unaligned_uint32 *p;
switch (addr & 3)
{
case 0:
p = (struct unaligned_uint32 *) ((addr & ~3ULL) + 2);
p->val = ((((((p->val >> 2) & MASK20) + value) & MASK20) << 2)
| (p->val & ~(MASK20 << 2)));
break;
case 1:
p = (struct unaligned_uint32 *) ((grub_uint8_t *) (addr & ~3ULL) + 7);
p->val = ((((((p->val >> 3) & MASK20) + value) & MASK20) << 3)
| (p->val & ~(MASK20 << 3)));
break;
case 2:
p = (struct unaligned_uint32 *) ((grub_uint8_t *) (addr & ~3ULL) + 12);
p->val = ((((((p->val >> 4) & MASK20) + value) & MASK20) << 4)
| (p->val & ~(MASK20 << 4)));
break;
}
}
#define MASKF21 ( ((1 << 23) - 1) & ~((1 << 7) | (1 << 8)) )
static grub_uint32_t
add_value_to_slot_21_real (grub_uint32_t a, grub_uint32_t value)
{
grub_uint32_t high, mid, low, c;
low = (a & 0x00007f);
mid = (a & 0x7fc000) >> 7;
high = (a & 0x003e00) << 7;
c = (low | mid | high) + value;
return (c & 0x7f) | ((c << 7) & 0x7fc000) | ((c >> 7) & 0x0003e00); //0x003e00
}
static void
add_value_to_slot_21 (grub_addr_t addr, grub_uint32_t value)
{
struct unaligned_uint32 *p;
switch (addr & 3)
{
case 0:
p = (struct unaligned_uint32 *) ((addr & ~3ULL) + 2);
p->val = ((add_value_to_slot_21_real (((p->val >> 2) & MASKF21), value) & MASKF21) << 2) | (p->val & ~(MASKF21 << 2));
break;
case 1:
p = (struct unaligned_uint32 *) ((grub_uint8_t *) (addr & ~3ULL) + 7);
p->val = ((add_value_to_slot_21_real (((p->val >> 3) & MASKF21), value) & MASKF21) << 3) | (p->val & ~(MASKF21 << 3));
break;
case 2:
p = (struct unaligned_uint32 *) ((grub_uint8_t *) (addr & ~3ULL) + 12);
p->val = ((add_value_to_slot_21_real (((p->val >> 4) & MASKF21), value) & MASKF21) << 4) | (p->val & ~(MASKF21 << 4));
break;
}
}
static const grub_uint8_t nopm[5] =
{
/* [MLX] nop.m 0x0 */
0x05, 0x00, 0x00, 0x00, 0x01
};
static const grub_uint8_t jump[0x20] =
{
/* ld8 r16=[r15],8 */
0x02, 0x80, 0x20, 0x1e, 0x18, 0x14,
/* mov r14=r1;; */
0xe0, 0x00, 0x04, 0x00, 0x42, 0x00,
/* nop.i 0x0 */
0x00, 0x00, 0x04, 0x00,
/* ld8 r1=[r15] */
0x11, 0x08, 0x00, 0x1e, 0x18, 0x10,
/* mov b6=r16 */
0x60, 0x80, 0x04, 0x80, 0x03, 0x00,
/* br.few b6;; */
0x60, 0x00, 0x80, 0x00
};
struct ia64_trampoline
{
/* nop.m */
grub_uint8_t nop[5];
/* movl r15 = addr*/
grub_uint8_t addr_hi[6];
grub_uint8_t e0;
grub_uint8_t addr_lo[4];
grub_uint8_t jump[0x20];
};
static void
make_trampoline (struct ia64_trampoline *tr, grub_uint64_t addr)
{
COMPILE_TIME_ASSERT (sizeof (struct ia64_trampoline)
== GRUB_IA64_DL_TRAMP_SIZE);
grub_memcpy (tr->nop, nopm, sizeof (tr->nop));
tr->addr_hi[0] = ((addr & 0xc00000) >> 16);
tr->addr_hi[1] = (addr >> 24) & 0xff;
tr->addr_hi[2] = (addr >> 32) & 0xff;
tr->addr_hi[3] = (addr >> 40) & 0xff;
tr->addr_hi[4] = (addr >> 48) & 0xff;
tr->addr_hi[5] = (addr >> 56) & 0xff;
tr->e0 = 0xe0;
tr->addr_lo[0] = ((addr & 0x000f) << 4) | 0x01;
tr->addr_lo[1] = (((addr & 0x0070) >> 4) | ((addr & 0x070000) >> 11)
| ((addr & 0x200000) >> 17));
tr->addr_lo[2] = ((addr & 0x1f80) >> 5) | ((addr & 0x180000) >> 19);
tr->addr_lo[3] = ((addr & 0xe000) >> 13) | 0x60;
grub_memcpy (tr->jump, jump, sizeof (tr->jump));
}
/* Relocate symbols. */
grub_err_t
grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr)
{
Elf_Ehdr *e = ehdr;
Elf_Shdr *s;
Elf_Word entsize;
unsigned i;
grub_uint64_t *gp, *gpptr;
struct ia64_trampoline *tr;
gp = (grub_uint64_t *) mod->base;
gpptr = (grub_uint64_t *) mod->got;
tr = mod->tramp;
/* Find a symbol table. */
for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
i < e->e_shnum;
i++, s = (Elf_Shdr *) ((char *) s + e->e_shentsize))
if (s->sh_type == SHT_SYMTAB)
break;
if (i == e->e_shnum)
return grub_error (GRUB_ERR_BAD_MODULE, "no symtab found");
entsize = s->sh_entsize;
for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
i < e->e_shnum;
i++, s = (Elf_Shdr *) ((char *) s + e->e_shentsize))
if (s->sh_type == SHT_RELA)
{
grub_dl_segment_t seg;
/* Find the target segment. */
for (seg = mod->segment; seg; seg = seg->next)
if (seg->section == s->sh_info)
break;
if (seg)
{
Elf_Rela *rel, *max;
for (rel = (Elf_Rela *) ((char *) e + s->sh_offset),
max = rel + s->sh_size / s->sh_entsize;
rel < max;
rel++)
{
grub_addr_t addr;
Elf_Sym *sym;
grub_uint64_t value;
if (seg->size < (rel->r_offset & ~3))
return grub_error (GRUB_ERR_BAD_MODULE,
"reloc offset is out of the segment");
addr = (grub_addr_t) seg->addr + rel->r_offset;
sym = (Elf_Sym *) ((char *) mod->symtab
+ entsize * ELF_R_SYM (rel->r_info));
/* On the PPC the value does not have an explicit
addend, add it. */
value = sym->st_value + rel->r_addend;
switch (ELF_R_TYPE (rel->r_info))
{
case R_IA64_PCREL21B:
{
grub_uint64_t noff;
make_trampoline (tr, value);
noff = ((char *) tr - (char *) (addr & ~3)) >> 4;
tr++;
if (noff & ~MASK19)
return grub_error (GRUB_ERR_BAD_OS,
"trampoline offset too big (%lx)", noff);
add_value_to_slot_20b (addr, noff);
}
break;
case R_IA64_SEGREL64LSB:
*(grub_uint64_t *) addr += value - (grub_addr_t) seg->addr;
break;
case R_IA64_FPTR64LSB:
case R_IA64_DIR64LSB:
*(grub_uint64_t *) addr += value;
break;
case R_IA64_PCREL64LSB:
*(grub_uint64_t *) addr += value - addr;
break;
case R_IA64_GPREL22:
add_value_to_slot_21 (addr, value - (grub_addr_t) gp);
break;
case R_IA64_LTOFF22X:
case R_IA64_LTOFF22:
if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
value = *(grub_uint64_t *) sym->st_value + rel->r_addend;
case R_IA64_LTOFF_FPTR22:
*gpptr = value;
add_value_to_slot_21 (addr, (grub_addr_t) gpptr - (grub_addr_t) gp);
gpptr++;
break;
/* We treat LTOFF22X as LTOFF22, so we can ignore LDXMOV. */
case R_IA64_LDXMOV:
break;
default:
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
"this relocation (0x%x) is not implemented yet",
ELF_R_TYPE (rel->r_info));
}
}
}
}
return GRUB_ERR_NONE;
}