New tools to help debug vboot failures.

utility/dump_fmap.c

+/*
+ * Copyright (c) 2010 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.
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+/* global variables */
+static int opt_extract = 0;
+static char *progname;
+static void *base_of_rom;
+
+/* FMAP structs. See http://code.google.com/p/flashmap/wiki/FmapSpec */
+#define FMAP_SIGLEN 8
+#define FMAP_NAMELEN 32
+#define FMAP_SEARCH_STRIDE 4
+typedef struct _FmapHeader {
+  char        fmap_signature[FMAP_SIGLEN]; /* avoiding endian issues */
+  uint8_t     fmap_ver_major;
+  uint8_t     fmap_ver_minor;
+  uint64_t    fmap_base;
+  uint32_t    fmap_size;
+  char        fmap_name[FMAP_NAMELEN];
+  uint16_t    fmap_nareas;
+} __attribute__((packed)) FmapHeader;
+
+typedef struct _AreaHeader {
+  uint32_t area_offset;
+  uint32_t area_size;
+  char     area_name[FMAP_NAMELEN];
+  uint16_t area_flags;
+} __attribute__((packed)) AreaHeader;
+
+
+/* Return 0 if successful */
+static int dump_fmap(void *ptr) {
+  int i,retval = 0;
+  char buf[80];                         // DWR: magic number
+  FmapHeader *fmh = (FmapHeader *)ptr;
+  AreaHeader *ah = (AreaHeader *)(ptr + sizeof(FmapHeader));
+
+  snprintf(buf, FMAP_SIGLEN+1, "%s", fmh->fmap_signature);
+  printf("fmap_signature   %s\n", buf);
+  printf("fmap_version:    %d.%d\n", fmh->fmap_ver_major, fmh->fmap_ver_minor);
+  printf("fmap_base:       0x%" PRIx64 "\n", fmh->fmap_base);
+  printf("fmap_size:       0x%08x (%d)\n", fmh->fmap_size, fmh->fmap_size);
+  snprintf(buf, FMAP_NAMELEN+1, "%s", fmh->fmap_name);
+  printf("fmap_name:       %s\n", buf);
+  printf("fmap_nareas:     %d\n", fmh->fmap_nareas);
+
+  for (i=0; i<fmh->fmap_nareas; i++) {
+    printf("area:            %d\n", i+1);
+    printf("area_offset:     0x%08x\n", ah->area_offset);
+    printf("area_size:       0x%08x (%d)\n", ah->area_size, ah->area_size);
+    snprintf(buf, FMAP_NAMELEN+1, "%s", ah->area_name);
+    printf("area_name:       %s\n", buf);
+
+    if (opt_extract) {
+      char *s;
+      for (s=buf; *s; s++)
+        if (*s == ' ')
+          *s = '_';
+      FILE *fp = fopen(buf,"wb");
+      if (!fp) {
+        fprintf(stderr, "%s: can't open %s: %s\n",
+                progname, buf, strerror(errno));
+        retval = 1;
+      } else {
+        if (1 != fwrite(base_of_rom + ah->area_offset, ah->area_size, 1, fp)) {
+          fprintf(stderr, "%s: can't write %s: %s\n",
+                  progname, buf, strerror(errno));
+          retval = 1;
+        } else {
+          printf("saved as \"%s\"\n", buf);
+        }
+        fclose(fp);
+      }
+    }
+
+    ah++;
+  }
+
+  return retval;
+}
+
+
+int main(int argc, char *argv[]) {
+  int c;
+  int errorcnt = 0;
+  struct stat sb;
+  int fd;
+  char *s;
+  size_t i;
+  int retval = 1;
+
+  progname = strrchr(argv[0], '/');
+  if (progname)
+    progname++;
+  else
+    progname = argv[0];
+
+  opterr = 0;                     /* quiet, you */
+  while ((c=getopt(argc, argv, ":x")) != -1) {
+    switch (c)
+    {
+    case 'x':
+      opt_extract = 1;
+      break;
+    case '?':
+      fprintf(stderr, "%s: unrecognized switch: -%c\n",
+              progname, optopt);
+      errorcnt++;
+      break;
+    case ':':
+      fprintf(stderr, "%s: missing argument to -%c\n",
+              progname, optopt);
+      errorcnt++;
+      break;
+    default:
+      errorcnt++;
+      break;
+    }
+  }
+
+  if (errorcnt || optind >= argc) {
+    fprintf(stderr,
+            "\nUsage:  %s [-x] FLASHIMAGE\n\n"
+            "Display (and extract with -x) the FMAP components from a BIOS image"
+            "\n\n",
+            progname);
+    return 1;
+  }
+
+  if (0 != stat(argv[optind], &sb)) {
+    fprintf(stderr, "%s: can't stat %s: %s\n",
+            progname,
+            argv[optind],
+            strerror(errno));
+    return 1;
+  }
+
+  fd = open(argv[optind], O_RDONLY);
+  if (fd < 0) {
+    fprintf(stderr, "%s: can't open %s: %s\n",
+            progname,
+            argv[optind],
+            strerror(errno));
+    return 1;
+  }
+  printf("opened %s\n", argv[optind]);
+
+  base_of_rom = mmap(0, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+  if (base_of_rom == (char *)-1) {
+    fprintf(stderr, "%s: can't mmap %s: %s\n",
+            progname,
+            argv[optind],
+            strerror(errno));
+    close(fd);
+    return 1;
+  }
+  close(fd);                            /* done with this now */
+
+  s = (char *)base_of_rom;
+  for (i=0; i<sb.st_size; i += FMAP_SEARCH_STRIDE) {
+    if (0 == strncmp(s, "__FMAP__", 8)) {
+      printf("hit at 0x%08x\n", (uint32_t)i);
+      retval = dump_fmap(s);
+      break;
+    }
+    s++;
+  }
+
+  if (0 != munmap(base_of_rom, sb.st_size)) {
+    fprintf(stderr, "%s: can't munmap %s: %s\n",
+            progname,
+            argv[optind],
+            strerror(errno));
+    return 1;
+  }
+
+  return retval;
+}