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 */
46static int
47ef_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
85ELF_RELOC(ELFCLASS64, ELFDATA2LSB, EM_RISCV, ef_riscv_reloc);
86