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-rw-r--r--tools/relocate-rela.c189
1 files changed, 189 insertions, 0 deletions
diff --git a/tools/relocate-rela.c b/tools/relocate-rela.c
new file mode 100644
index 0000000..93b4c39
--- /dev/null
+++ b/tools/relocate-rela.c
@@ -0,0 +1,189 @@
+/*
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause
+ *
+ * 64-bit and little-endian target only until we need to support a different
+ * arch that needs this.
+ */
+
+#include <elf.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef R_AARCH64_RELATIVE
+#define R_AARCH64_RELATIVE 1027
+#endif
+
+static const bool debug_en;
+
+static void debug(const char *fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ if (debug_en)
+ vprintf(fmt, args);
+}
+
+static bool supported_rela(Elf64_Rela *rela)
+{
+ uint64_t mask = 0xffffffffULL; /* would be different on 32-bit */
+ uint32_t type = rela->r_info & mask;
+
+ switch (type) {
+#ifdef R_AARCH64_RELATIVE
+ case R_AARCH64_RELATIVE:
+ return true;
+#endif
+ default:
+ fprintf(stderr, "warning: unsupported relocation type %"
+ PRIu32 " at %" PRIx64 "\n",
+ type, rela->r_offset);
+
+ return false;
+ }
+}
+
+static inline uint64_t swap64(uint64_t val)
+{
+ return ((val >> 56) & 0x00000000000000ffULL) |
+ ((val >> 40) & 0x000000000000ff00ULL) |
+ ((val >> 24) & 0x0000000000ff0000ULL) |
+ ((val >> 8) & 0x00000000ff000000ULL) |
+ ((val << 8) & 0x000000ff00000000ULL) |
+ ((val << 24) & 0x0000ff0000000000ULL) |
+ ((val << 40) & 0x00ff000000000000ULL) |
+ ((val << 56) & 0xff00000000000000ULL);
+}
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+static inline uint64_t be64(uint64_t val)
+{
+ return swap64(val);
+}
+
+static inline uint64_t le64(uint64_t val)
+{
+ return val;
+}
+#else
+static inline uint64_t le64(uint64_t val)
+{
+ return swap64(val);
+}
+
+static inline uint64_t be64(uint64_t val)
+{
+ return val;
+}
+#endif
+
+static bool read_num(const char *str, uint64_t *num)
+{
+ char *endptr;
+ *num = strtoull(str, &endptr, 16);
+ return str[0] && !endptr[0];
+}
+
+int main(int argc, char **argv)
+{
+ FILE *f;
+ int i, num;
+ uint64_t rela_start, rela_end, text_base;
+
+ if (argc != 5) {
+ fprintf(stderr, "Statically apply ELF rela relocations\n");
+ fprintf(stderr, "Usage: %s <bin file> <text base> " \
+ "<rela start> <rela end>\n", argv[0]);
+ fprintf(stderr, "All numbers in hex.\n");
+ return 1;
+ }
+
+ f = fopen(argv[1], "r+b");
+ if (!f) {
+ fprintf(stderr, "%s: Cannot open %s: %s\n",
+ argv[0], argv[1], strerror(errno));
+ return 2;
+ }
+
+ if (!read_num(argv[2], &text_base) ||
+ !read_num(argv[3], &rela_start) ||
+ !read_num(argv[4], &rela_end)) {
+ fprintf(stderr, "%s: bad number\n", argv[0]);
+ return 3;
+ }
+
+ if (rela_start > rela_end || rela_start < text_base ||
+ (rela_end - rela_start) % 24) {
+ fprintf(stderr, "%s: bad rela bounds\n", argv[0]);
+ return 3;
+ }
+
+ rela_start -= text_base;
+ rela_end -= text_base;
+
+ num = (rela_end - rela_start) / sizeof(Elf64_Rela);
+
+ for (i = 0; i < num; i++) {
+ Elf64_Rela rela, swrela;
+ uint64_t pos = rela_start + sizeof(Elf64_Rela) * i;
+ uint64_t addr;
+
+ if (fseek(f, pos, SEEK_SET) < 0) {
+ fprintf(stderr, "%s: %s: seek to %" PRIx64
+ " failed: %s\n",
+ argv[0], argv[1], pos, strerror(errno));
+ }
+
+ if (fread(&rela, sizeof(rela), 1, f) != 1) {
+ fprintf(stderr, "%s: %s: read rela failed at %"
+ PRIx64 "\n",
+ argv[0], argv[1], pos);
+ return 4;
+ }
+
+ swrela.r_offset = le64(rela.r_offset);
+ swrela.r_info = le64(rela.r_info);
+ swrela.r_addend = le64(rela.r_addend);
+
+ if (!supported_rela(&swrela))
+ continue;
+
+ debug("Rela %" PRIx64 " %" PRIu64 " %" PRIx64 "\n",
+ swrela.r_offset, swrela.r_info, swrela.r_addend);
+
+ if (swrela.r_offset < text_base) {
+ fprintf(stderr, "%s: %s: bad rela at %" PRIx64 "\n",
+ argv[0], argv[1], pos);
+ return 4;
+ }
+
+ addr = swrela.r_offset - text_base;
+
+ if (fseek(f, addr, SEEK_SET) < 0) {
+ fprintf(stderr, "%s: %s: seek to %"
+ PRIx64 " failed: %s\n",
+ argv[0], argv[1], addr, strerror(errno));
+ }
+
+ if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) {
+ fprintf(stderr, "%s: %s: write failed at %" PRIx64 "\n",
+ argv[0], argv[1], addr);
+ return 4;
+ }
+ }
+
+ if (fclose(f) < 0) {
+ fprintf(stderr, "%s: %s: close failed: %s\n",
+ argv[0], argv[1], strerror(errno));
+ return 4;
+ }
+
+ return 0;
+}