1 files changed, 88 insertions, 0 deletions
diff --git a/utility/dump_kernel_config_lib.c b/utility/dump_kernel_config_lib.c
new file mode 100644
index 00000000..a6989e1c
--- /dev/null
+++ b/utility/dump_kernel_config_lib.c
@@ -0,0 +1,88 @@
+/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Exports the kernel commandline from a given partition/image.
+ */
+
+#include <stdio.h>
+#include <sys/mman.h>
+
+#include "dump_kernel_config.h"
+#include "host_common.h"
+#include "kernel_blob.h"
+#include "vboot_api.h"
+
+uint8_t* find_kernel_config(uint8_t* blob, uint64_t blob_size,
+                            uint64_t kernel_body_load_address) {
+
+  VbKeyBlockHeader* key_block;
+  VbKernelPreambleHeader* preamble;
+  uint32_t now = 0;
+  uint32_t offset = 0;
+
+  /* Skip the key block */
+  key_block = (VbKeyBlockHeader*)blob;
+  now += key_block->key_block_size;
+  if (now + blob > blob + blob_size) {
+    VbExError("key_block_size advances past the end of the blob\n");
+    return NULL;
+  }
+
+  /* Open up the preamble */
+  preamble = (VbKernelPreambleHeader*)(blob + now);
+  now += preamble->preamble_size;
+  if (now + blob > blob + blob_size) {
+    VbExError("preamble_size advances past the end of the blob\n");
+    return NULL;
+  }
+
+  /* Read body_load_address from preamble if no kernel_body_load_address */
+  if (kernel_body_load_address == CROS_NO_ENTRY_ADDR)
+    kernel_body_load_address = preamble->body_load_address;
+
+  /* The x86 kernels have a pointer to the kernel commandline in the zeropage
+   * table, but that's irrelevant for ARM. Both types keep the config blob in
+   * the same place, so just go find it. */
+  offset = preamble->bootloader_address -
+    (kernel_body_load_address + CROS_PARAMS_SIZE +
+     CROS_CONFIG_SIZE) + now;
+  if (offset > blob_size) {
+    VbExError("params are outside of the memory blob: %x\n", offset);
+    return NULL;
+  }
+  return blob + offset;
+}
+
+void* MapFile(const char* filename, size_t *size) {
+  FILE* f;
+  uint8_t* buf;
+  long file_size = 0;
+
+  f = fopen(filename, "rb");
+  if (!f) {
+    VBDEBUG(("Unable to open file %s\n", filename));
+    return NULL;
+  }
+
+  fseek(f, 0, SEEK_END);
+  file_size = ftell(f);
+  rewind(f);
+
+  if (file_size <= 0) {
+    fclose(f);
+    return NULL;
+  }
+  *size = (size_t) file_size;
+
+  /* Uses a host primitive as this is not meant for firmware use. */
+  buf = mmap(NULL, *size, PROT_READ, MAP_PRIVATE, fileno(f), 0);
+  if (buf == MAP_FAILED) {
+    VbExError("Failed to mmap the file %s\n", filename);
+    fclose(f);
+    return NULL;
+  }
+
+  fclose(f);
+  return buf;
+}