summaryrefslogtreecommitdiffstats
path: root/grub-core/kern/sparc64/dl.c
blob: f3d960186ba56b9b4658a444d7ac1fa61f6bcf01 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
/* 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/i18n.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] != ELFDATA2MSB
      || e->e_machine != EM_SPARCV9)
    return grub_error (GRUB_ERR_BAD_OS, N_("invalid arch-dependent ELF magic"));

  return GRUB_ERR_NONE;
}

#pragma GCC diagnostic ignored "-Wcast-align"

struct trampoline
{
  grub_uint8_t code[0x28];
  grub_uint64_t addr;
};

static const grub_uint8_t trampoline_code[0x28] =
{
  /* 0:  */ 0x82, 0x10, 0x00, 0x0f,	/* mov  %o7, %g1 */
  /* 4:  */ 0x40, 0x00, 0x00, 0x02, 	/* call  0xc */
  /* 8:  */ 0x01, 0x00, 0x00, 0x00, 	/* nop */
  /* c:  */ 0x9e, 0x1b, 0xc0, 0x01, 	/* xor  %o7, %g1, %o7 */
  /* 10: */ 0x82, 0x18, 0x40, 0x0f, 	/* xor  %g1, %o7, %g1 */
  /* 14: */ 0x9e, 0x1b, 0xc0, 0x01, 	/* xor  %o7, %g1, %o7 */
  /* 18: */ 0xc2, 0x58, 0x60, 0x24, 	/* ldx  [ %g1 + 0x24 ], %g1 */
  /* 1c: */ 0x81, 0xc0, 0x40, 0x00, 	/* jmp  %g1 */
  /* 20: */ 0x01, 0x00, 0x00, 0x00, 	/* nop */
  /* 24: */ 0x01, 0x00, 0x00, 0x00, 	/* nop */
};

grub_err_t
grub_arch_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,
				 grub_size_t *got)
{
  const Elf_Ehdr *e = ehdr;
  const Elf_Shdr *s;
  unsigned i;

  *tramp = 0;
  *got = 0;

  for (i = 0, s = (const Elf_Shdr *) ((grub_addr_t) e + e->e_shoff);
       i < e->e_shnum;
       i++, s = (const Elf_Shdr *) ((grub_addr_t) s + e->e_shentsize))
    if (s->sh_type == SHT_REL || s->sh_type == SHT_RELA)
      {
	const Elf_Rel *rel, *max;

	for (rel = (const Elf_Rel *) ((grub_addr_t) e + s->sh_offset),
	       max = rel + s->sh_size / s->sh_entsize;
	     rel < max;
	     rel = (const Elf_Rel *) ((grub_addr_t) rel + s->sh_entsize))
	  switch (ELF_R_TYPE (rel->r_info))
	    {
	    case R_SPARC_WDISP30:
	      {
		*tramp += sizeof (struct trampoline);
		break;
	      }
	    }
      }

  return GRUB_ERR_NONE;
}

/* Relocate symbols.  */
grub_err_t
grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
			       Elf_Shdr *s, grub_dl_segment_t seg)
{
  Elf_Rela *rel, *max;

  for (rel = (Elf_Rela *) ((char *) ehdr + s->sh_offset),
	 max = (Elf_Rela *) ((char *) rel + s->sh_size);
       rel < max;
       rel = (Elf_Rela *) ((char *) rel + s->sh_entsize))
    {
      Elf_Word *addr;
      Elf_Sym *sym;
      Elf_Addr value;

      if (seg->size < rel->r_offset)
	return grub_error (GRUB_ERR_BAD_MODULE,
			   "reloc offset is out of the segment");

      addr = (Elf_Word *) ((char *) seg->addr + rel->r_offset);
      sym = (Elf_Sym *) ((char *) mod->symtab
			 + mod->symsize * ELF_R_SYM (rel->r_info));

      value = sym->st_value + rel->r_addend;
      switch (ELF_R_TYPE (rel->r_info) & 0xff)
	{
	case R_SPARC_32: /* 3 V-word32 */
	  if (value & 0xFFFFFFFF00000000)
	    return grub_error (GRUB_ERR_BAD_MODULE,
			       "address out of 32 bits range");
	  *addr = value;
	  break;
	case R_SPARC_WDISP30: /* 7 V-disp30 */
	  if (((value - (Elf_Addr) addr) & 0xFFFFFFFF00000000) &&
	       (((value - (Elf_Addr) addr) & 0xFFFFFFFF00000000)
		!= 0xFFFFFFFF00000000))
	    {
	      struct trampoline *tp = mod->trampptr;
	      mod->trampptr = tp + 1;
	      grub_memcpy (tp->code, trampoline_code, sizeof (tp->code));
	      tp->addr = value;
	      value = (Elf_Addr) tp;
	    }

	  if (((value - (Elf_Addr) addr) & 0xFFFFFFFF00000000) &&
	      (((value - (Elf_Addr) addr) & 0xFFFFFFFF00000000)
	       != 0xFFFFFFFF00000000))
	    return grub_error (GRUB_ERR_BAD_MODULE,
			       "displacement out of 30 bits range");
	  *addr = (*addr & 0xC0000000) |
	    (((grub_int32_t) ((value - (Elf_Addr) addr) >> 2)) &
	     0x3FFFFFFF);
	  break;
	case R_SPARC_HH22: /* 9 V-imm22 */
	  *addr = (*addr & 0xFFC00000) | ((value >> 42) & 0x3FFFFF);
	  break;
	case R_SPARC_HM10: /* 12 T-simm13 */
	  *addr = (*addr & 0xFFFFFC00) | ((value >> 32) & 0x3FF);
	  break;
	case R_SPARC_HI22: /* 9 V-imm22 */
	  if (value >> 32)
	    return grub_error (GRUB_ERR_BAD_MODULE,
			       "address out of 32 bits range");
	  /* Fallthrough.  */
	case R_SPARC_LM22:
	  *addr = (*addr & 0xFFC00000) | ((value >> 10) & 0x3FFFFF);
	  break;
	case R_SPARC_LO10: /* 12 T-simm13 */
	  *addr = (*addr & 0xFFFFFC00) | (value & 0x3FF);
	  break;
	case R_SPARC_64: /* 32 V-xwords64 */
	  *(Elf_Xword *) addr = value;
	  break;
	case R_SPARC_OLO10:
	  *addr = (*addr & ~0x1fff)
	    | (((value & 0x3ff) +
		(ELF_R_TYPE (rel->r_info) >> 8))
	       & 0x1fff);
	  break;
	default:
	  {
	    char rel_info[17]; /* log16(2^64) = 16, plus NUL. */

	    grub_snprintf (rel_info, sizeof (rel_info) - 1, "%" PRIxGRUB_UINT64_T,
			   ELF_R_TYPE (rel->r_info));
	    return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
			       N_("relocation 0x%s is not implemented yet"), rel_info);
	  }
	}
    }

  return GRUB_ERR_NONE;
}