This patch introduces an ELF parsing test; the 5th byte of the ELF header
must be 0x01 for a 32-bit process. A basic sanity check is required to ensure
that we are actually testing a 32-bit build.
Signed-off-by: Dev Jain <dev.jain@xxxxxxx>
---
tools/testing/selftests/arm/elf/parse_elf.c | 75 +++++++++++++++++++++
1 file changed, 75 insertions(+)
create mode 100644 tools/testing/selftests/arm/elf/parse_elf.c
diff --git a/tools/testing/selftests/arm/elf/parse_elf.c b/tools/testing/selftests/arm/elf/parse_elf.c
new file mode 100644
index 000000000000..decd65699858
--- /dev/null
+++ b/tools/testing/selftests/arm/elf/parse_elf.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 ARM Limited
+ *
+ * Author : Dev Jain <dev.jain@xxxxxxx>
+ *
+ * Parse elf header to confirm 32-bit process
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <elf.h>
+#include <stdint.h>
+
+#include <kselftest.h>
+
+/* The ELF file header. This appears at the start of every ELF file. */
+
+struct elf_header {
+ unsigned char e_ident[16]; /* Magic number and other info */
+ uint16_t e_type; /* Object file type */
+ uint16_t e_machine; /* Architecture */
+ uint32_t e_version; /* Object file version */
+ uint64_t e_entry; /* Entry point virtual address */
+ uint64_t e_phoff; /* Program header table file offset */
+ uint64_t e_shoff; /* Section header table file offset */
+ uint32_t e_flags; /* Processor-specific flags */
+ uint16_t e_ehsize; /* ELF header size in bytes */
+ uint16_t e_phentsize; /* Program header table entry size */
+ uint16_t e_phnum; /* Program header table entry count */
+ uint16_t e_shentsize; /* Section header table entry size */
+ uint16_t e_shnum; /* Section header table entry count */
+ uint16_t e_shstrndx; /* Section header string table index */
+};
+
+static int read_elf_header(const char *elfFile)
+{
+ struct elf_header header;
+ FILE *file;
+
+ file = fopen(elfFile, "r");
+ if (file) {
+
+ /* store header in struct */
+ fread(&header, 1, sizeof(header), file);
+ fclose(file);
+
+ /* sanity check: does it really follow ELF format */
+ if (header.e_ident[0] == 0x7f &&
+ header.e_ident[1] == 'E' &&
+ header.e_ident[2] == 'L' &&
+ header.e_ident[3] == 'F') {
+ if (header.e_ident[4] == 0x01)
+ return 0;
+ return 1;
+ }
+ ksft_exit_fail_msg("Cannot parse /proc/self/exe\n");
+ }
+ ksft_exit_fail_msg("Cannot open /proc/self/exe\n");
+ exit(EXIT_FAILURE);
+}
+
+int main(int argc, char *argv[])
+{
+ const char *file_name;
+
+ ksft_print_header();
+ ksft_set_plan(1);
+
+ file_name = "/proc/self/exe";
+ ksft_test_result(read_elf_header(file_name) == 0, "ELF is 32 bit\n");
+ ksft_finished();
+}
--
2.39.2
