1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2018 John Baldwin <jhb@FreeBSD.org>
5 *
6 * This software was developed by SRI International and the University of
7 * Cambridge Computer Laboratory (Department of Computer Science and
8 * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
9 * DARPA SSITH research programme.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include <sys/endian.h>
34
35 #include <err.h>
36 #include <errno.h>
37 #include <gelf.h>
38
39 #include "ef.h"
40
41 /*
42 * Apply relocations to the values obtained from the file. `relbase' is the
43 * target relocation address of the section, and `dataoff/len' is the region
44 * that is to be relocated, and has been copied to *dest
45 */
46 static int
ef_riscv_reloc(struct elf_file * ef,const void * reldata,Elf_Type reltype,GElf_Addr relbase,GElf_Addr dataoff,size_t len,void * dest)47 ef_riscv_reloc(struct elf_file *ef, const void *reldata, Elf_Type reltype,
48 GElf_Addr relbase, GElf_Addr dataoff, size_t len, void *dest)
49 {
50 char *where;
51 GElf_Addr addr, addend;
52 GElf_Size rtype, symidx;
53 const GElf_Rela *rela;
54
55 switch (reltype) {
56 case ELF_T_RELA:
57 rela = (const GElf_Rela *)reldata;
58 where = (char *)dest + (relbase + rela->r_offset - dataoff);
59 addend = rela->r_addend;
60 rtype = GELF_R_TYPE(rela->r_info);
61 symidx = GELF_R_SYM(rela->r_info);
62 break;
63 default:
64 return (EINVAL);
65 }
66
67 if (where < (char *)dest || where >= (char *)dest + len)
68 return (0);
69
70 switch (rtype) {
71 case R_RISCV_64: /* S + A */
72 addr = EF_SYMADDR(ef, symidx) + addend;
73 le64enc(where, addr);
74 break;
75 case R_RISCV_RELATIVE: /* B + A */
76 addr = relbase + addend;
77 le64enc(where, addr);
78 break;
79 default:
80 warnx("unhandled relocation type %d", (int)rtype);
81 }
82 return (0);
83 }
84
85 ELF_RELOC(ELFCLASS64, ELFDATA2LSB, EM_RISCV, ef_riscv_reloc);
86