Add capability to auto-hash correct size for EC-RO or EC-RW

Otherwise the host needs to tell the EC how big this image is (which
it knows, but it's inconvenient for it to provide).

BUG=chrome-os-partner:13511
BRANCH=all
TEST=manual

1. ectool echash recalc ro -> prints hash of RO code (offset 0)
2. ectool echash recalc rw -> prints hash of RW code (offset non-zero)

In each case, size should be an exact number and not the size of the
whole RO or RW section.  So for link, output should be something similar to:

  localhost ~ # ectool echash recalc ro
  Hashing EC-RO...
  status:  done
  type:    SHA-256
  offset:  0x00000000
  size:    0x00012a64
  hash:    03a66c076d6dd4b4aa9ed6386713f45291f5143f9af2093003e632485899daf1
  localhost ~ # ectool echash recalc rw
  Hashing EC-RW...
  status:  done
  type:    SHA-256
  offset:  0x00014000
  size:    0x000123d1
  hash:    0d6225e70f0b1e0419e987370371e00783f945827ef25915a8fb8549159dd2a4

Signed-off-by: Randall Spangler <rspangler@chromium.org>

3. At ec console, 'hash ro' or 'hash rw' should regenerate the same
hash values printed above.

Change-Id: I3f6085d29927b8cdf9dabc6930f0fdc7222bd8b5
Reviewed-on: https://gerrit.chromium.org/gerrit/33123
Tested-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Commit-Ready: Randall Spangler <rspangler@chromium.org>

1 files changed, 30 insertions, 12 deletions

diff --git a/util/ectool.c b/util/ectool.c
index 90b0d558ee..4fbc6ce781 100644
--- a/util/ectool.c
+++ b/util/ectool.c
@@ -1990,6 +1990,10 @@ static int ec_hash_help(const char *cmd)
 	printf("  %s abort                  - abort hashing\n", cmd);
 	printf("  %s start [<offset> <size> [<nonce>]] - start hashing\n", cmd);
 	printf("  %s recalc [<offset> <size> [<nonce>]] - sync rehash\n", cmd);
+	printf("\n"
+	       "If <offset> is RO or RW, offset and size are computed\n"
+	       "automatically for the EC-RO or EC-RW firmware image.\n");
+
 	return 0;
 }
 
@@ -2060,21 +2064,36 @@ int cmd_ec_hash(int argc, char *argv[])
 	else
 		return ec_hash_help(argv[0]);
 
-	if (argc < 4) {
-		fprintf(stderr, "Must specify offset and size\n");
-		return -1;
-	}
-
 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
-	p.offset = strtol(argv[2], &e, 0);
-	if (e && *e) {
-		fprintf(stderr, "Bad offset.\n");
+
+	if (argc < 3) {
+		fprintf(stderr, "Must specify offset\n");
 		return -1;
 	}
-	p.size = strtol(argv[3], &e, 0);
-	if (e && *e) {
-		fprintf(stderr, "Bad size.\n");
+
+	if (!strcasecmp(argv[2], "ro")) {
+		p.offset = EC_VBOOT_HASH_OFFSET_RO;
+		p.size = 0;
+		printf("Hashing EC-RO...\n");
+	} else if (!strcasecmp(argv[2], "rw")) {
+		p.offset = EC_VBOOT_HASH_OFFSET_RW;
+		p.size = 0;
+		printf("Hashing EC-RW...\n");
+	} else if (argc < 4) {
+		fprintf(stderr, "Must specify size\n");
 		return -1;
+	} else {
+		p.offset = strtol(argv[2], &e, 0);
+		if (e && *e) {
+			fprintf(stderr, "Bad offset.\n");
+			return -1;
+		}
+		p.size = strtol(argv[3], &e, 0);
+		if (e && *e) {
+			fprintf(stderr, "Bad size.\n");
+			return -1;
+		}
+		printf("Hashing %d bytes at offset %d...\n", p.size, p.offset);
 	}
 
 	if (argc == 5) {
@@ -2092,7 +2111,6 @@ int cmd_ec_hash(int argc, char *argv[])
 	} else
 		p.nonce_size = 0;
 
-	printf("Hashing %d bytes at offset %d...\n", p.size, p.offset);
 	rv = ec_command(EC_CMD_VBOOT_HASH, 0, &p, sizeof(p), &r, sizeof(r));
 	if (rv < 0)
 		return rv;