Scott Wood | 8137af1 | 2013-12-14 11:47:32 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2013 Freescale Semiconductor, Inc. |
| 3 | * |
| 4 | * SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause |
| 5 | * |
| 6 | * 64-bit and little-endian target only until we need to support a different |
| 7 | * arch that needs this. |
| 8 | */ |
| 9 | |
| 10 | #include <elf.h> |
| 11 | #include <errno.h> |
| 12 | #include <inttypes.h> |
| 13 | #include <stdarg.h> |
| 14 | #include <stdbool.h> |
| 15 | #include <stdio.h> |
| 16 | #include <stdlib.h> |
| 17 | #include <string.h> |
| 18 | |
| 19 | #ifndef R_AARCH64_RELATIVE |
| 20 | #define R_AARCH64_RELATIVE 1027 |
| 21 | #endif |
| 22 | |
| 23 | static const bool debug_en; |
| 24 | |
| 25 | static void debug(const char *fmt, ...) |
| 26 | { |
| 27 | va_list args; |
| 28 | |
| 29 | va_start(args, fmt); |
| 30 | if (debug_en) |
| 31 | vprintf(fmt, args); |
| 32 | } |
| 33 | |
| 34 | static bool supported_rela(Elf64_Rela *rela) |
| 35 | { |
| 36 | uint64_t mask = 0xffffffffULL; /* would be different on 32-bit */ |
| 37 | uint32_t type = rela->r_info & mask; |
| 38 | |
| 39 | switch (type) { |
| 40 | #ifdef R_AARCH64_RELATIVE |
| 41 | case R_AARCH64_RELATIVE: |
| 42 | return true; |
| 43 | #endif |
| 44 | default: |
| 45 | fprintf(stderr, "warning: unsupported relocation type %" |
| 46 | PRIu32 " at %" PRIx64 "\n", |
| 47 | type, rela->r_offset); |
| 48 | |
| 49 | return false; |
| 50 | } |
| 51 | } |
| 52 | |
| 53 | static inline uint64_t swap64(uint64_t val) |
| 54 | { |
| 55 | return ((val >> 56) & 0x00000000000000ffULL) | |
| 56 | ((val >> 40) & 0x000000000000ff00ULL) | |
| 57 | ((val >> 24) & 0x0000000000ff0000ULL) | |
| 58 | ((val >> 8) & 0x00000000ff000000ULL) | |
| 59 | ((val << 8) & 0x000000ff00000000ULL) | |
| 60 | ((val << 24) & 0x0000ff0000000000ULL) | |
| 61 | ((val << 40) & 0x00ff000000000000ULL) | |
| 62 | ((val << 56) & 0xff00000000000000ULL); |
| 63 | } |
| 64 | |
| 65 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
| 66 | static inline uint64_t be64(uint64_t val) |
| 67 | { |
| 68 | return swap64(val); |
| 69 | } |
| 70 | |
| 71 | static inline uint64_t le64(uint64_t val) |
| 72 | { |
| 73 | return val; |
| 74 | } |
| 75 | #else |
| 76 | static inline uint64_t le64(uint64_t val) |
| 77 | { |
| 78 | return swap64(val); |
| 79 | } |
| 80 | |
| 81 | static inline uint64_t be64(uint64_t val) |
| 82 | { |
| 83 | return val; |
| 84 | } |
| 85 | #endif |
| 86 | |
| 87 | static bool read_num(const char *str, uint64_t *num) |
| 88 | { |
| 89 | char *endptr; |
| 90 | *num = strtoull(str, &endptr, 16); |
| 91 | return str[0] && !endptr[0]; |
| 92 | } |
| 93 | |
| 94 | int main(int argc, char **argv) |
| 95 | { |
| 96 | FILE *f; |
| 97 | int i, num; |
| 98 | uint64_t rela_start, rela_end, text_base; |
| 99 | |
| 100 | if (argc != 5) { |
| 101 | fprintf(stderr, "Statically apply ELF rela relocations\n"); |
| 102 | fprintf(stderr, "Usage: %s <bin file> <text base> " \ |
| 103 | "<rela start> <rela end>\n", argv[0]); |
| 104 | fprintf(stderr, "All numbers in hex.\n"); |
| 105 | return 1; |
| 106 | } |
| 107 | |
| 108 | f = fopen(argv[1], "r+b"); |
| 109 | if (!f) { |
| 110 | fprintf(stderr, "%s: Cannot open %s: %s\n", |
| 111 | argv[0], argv[1], strerror(errno)); |
| 112 | return 2; |
| 113 | } |
| 114 | |
| 115 | if (!read_num(argv[2], &text_base) || |
| 116 | !read_num(argv[3], &rela_start) || |
| 117 | !read_num(argv[4], &rela_end)) { |
| 118 | fprintf(stderr, "%s: bad number\n", argv[0]); |
| 119 | return 3; |
| 120 | } |
| 121 | |
| 122 | if (rela_start > rela_end || rela_start < text_base || |
Masahiro Yamada | e60cfd5 | 2014-02-04 10:58:31 +0900 | [diff] [blame^] | 123 | (rela_end - rela_start) % sizeof(Elf64_Rela)) { |
Scott Wood | 8137af1 | 2013-12-14 11:47:32 +0800 | [diff] [blame] | 124 | fprintf(stderr, "%s: bad rela bounds\n", argv[0]); |
| 125 | return 3; |
| 126 | } |
| 127 | |
| 128 | rela_start -= text_base; |
| 129 | rela_end -= text_base; |
| 130 | |
| 131 | num = (rela_end - rela_start) / sizeof(Elf64_Rela); |
| 132 | |
| 133 | for (i = 0; i < num; i++) { |
| 134 | Elf64_Rela rela, swrela; |
| 135 | uint64_t pos = rela_start + sizeof(Elf64_Rela) * i; |
| 136 | uint64_t addr; |
| 137 | |
| 138 | if (fseek(f, pos, SEEK_SET) < 0) { |
| 139 | fprintf(stderr, "%s: %s: seek to %" PRIx64 |
| 140 | " failed: %s\n", |
| 141 | argv[0], argv[1], pos, strerror(errno)); |
| 142 | } |
| 143 | |
| 144 | if (fread(&rela, sizeof(rela), 1, f) != 1) { |
| 145 | fprintf(stderr, "%s: %s: read rela failed at %" |
| 146 | PRIx64 "\n", |
| 147 | argv[0], argv[1], pos); |
| 148 | return 4; |
| 149 | } |
| 150 | |
| 151 | swrela.r_offset = le64(rela.r_offset); |
| 152 | swrela.r_info = le64(rela.r_info); |
| 153 | swrela.r_addend = le64(rela.r_addend); |
| 154 | |
| 155 | if (!supported_rela(&swrela)) |
| 156 | continue; |
| 157 | |
| 158 | debug("Rela %" PRIx64 " %" PRIu64 " %" PRIx64 "\n", |
| 159 | swrela.r_offset, swrela.r_info, swrela.r_addend); |
| 160 | |
| 161 | if (swrela.r_offset < text_base) { |
| 162 | fprintf(stderr, "%s: %s: bad rela at %" PRIx64 "\n", |
| 163 | argv[0], argv[1], pos); |
| 164 | return 4; |
| 165 | } |
| 166 | |
| 167 | addr = swrela.r_offset - text_base; |
| 168 | |
| 169 | if (fseek(f, addr, SEEK_SET) < 0) { |
| 170 | fprintf(stderr, "%s: %s: seek to %" |
| 171 | PRIx64 " failed: %s\n", |
| 172 | argv[0], argv[1], addr, strerror(errno)); |
| 173 | } |
| 174 | |
| 175 | if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) { |
| 176 | fprintf(stderr, "%s: %s: write failed at %" PRIx64 "\n", |
| 177 | argv[0], argv[1], addr); |
| 178 | return 4; |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | if (fclose(f) < 0) { |
| 183 | fprintf(stderr, "%s: %s: close failed: %s\n", |
| 184 | argv[0], argv[1], strerror(errno)); |
| 185 | return 4; |
| 186 | } |
| 187 | |
| 188 | return 0; |
| 189 | } |