[U-Boot] [PATCH v3 11/20] Add hash command to perform hashing using various algorithms

[Simon Glass]

This new command supports hashing SHA1 and SHA256. It could be extended
to others such as MD5 and the CRC algorithms. The syntax is modeled on
those:

   hash <algorithm> <address> <length> [*<dest_addr> | <dest_envvar>]

to calculate a hash, and:

   hash -v <algorithm> <address> <length> [*<verify_addr> | <verify_envvar>]

to verify a hash.

Use CONFIG_CMD_HASH to enable the command, CONFIG_SHA1 to enable SHA1 and
CONFIG_SHA256 to enable SHA256.

The existing sha1sum command remains.

Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v3:
- Correct hash command help to say 'hash' instead of 'sha1sum'

Changes in v2:
- Add new hash command to support generic hash API

 README                   |   18 +++++++++++++
 common/Makefile          |    1 +
 common/cmd_hash.c        |   63 ++++++++++++++++++++++++++++++++++++++++++++++
 include/config_cmd_all.h |    1 +
 4 files changed, 83 insertions(+), 0 deletions(-)
 create mode 100644 common/cmd_hash.c

diff --git a/README b/README
index 027fa46..40158bb 100644
--- a/README
+++ b/README
@@ -822,6 +822,7 @@ The following options need to be configured:
 		CONFIG_CMD_GETTIME	* Get time since boot
 		CONFIG_CMD_GO		* the 'go' command (exec code)
 		CONFIG_CMD_GREPENV	* search environment
+		CONFIG_CMD_HASH		* calculate hash / digest
 		CONFIG_CMD_HWFLOW	* RTS/CTS hw flow control
 		CONFIG_CMD_I2C		* I2C serial bus support
 		CONFIG_CMD_IDE		* IDE harddisk support
@@ -2391,6 +2392,23 @@ CBFS (Coreboot Filesystem) support
 		A better solution is to properly configure the firewall,
 		but sometimes that is not allowed.
 
+- Hashing support:
+		CONFIG_CMD_HASH
+
+		This enables a generic 'hash' command which can produce
+		hashes / digests from a few algorithms (e.g. SHA1, SHA256).
+
+		CONFIG_HASH_VERIFY
+
+		Enable the hash verify command (hash -v). This adds to code
+		size a little.
+
+		CONFIG_SHA1 - support SHA1 hashing
+		CONFIG_SHA256 - support SHA256 hashing
+
+		Note: There is also a sha1sum command, which should perhaps
+		be deprecated in favour of 'hash sha1'.
+
 - Show boot progress:
 		CONFIG_SHOW_BOOT_PROGRESS
 
diff --git a/common/Makefile b/common/Makefile
index c451c3d..2c28e93 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -104,6 +104,7 @@ COBJS-$(CONFIG_CMD_FS_GENERIC) += cmd_fs.o
 COBJS-$(CONFIG_CMD_GETTIME) += cmd_gettime.o
 COBJS-$(CONFIG_CMD_GPIO) += cmd_gpio.o
 COBJS-$(CONFIG_CMD_I2C) += cmd_i2c.o
+COBJS-$(CONFIG_CMD_HASH) += cmd_hash.o
 COBJS-$(CONFIG_CMD_IDE) += cmd_ide.o
 COBJS-$(CONFIG_CMD_IMMAP) += cmd_immap.o
 COBJS-$(CONFIG_CMD_INI) += cmd_ini.o
diff --git a/common/cmd_hash.c b/common/cmd_hash.c
new file mode 100644
index 0000000..689c608
--- /dev/null
+++ b/common/cmd_hash.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2012 The Chromium OS Authors.
+ *
+ * (C) Copyright 2011
+ * Joe Hershberger, National Instruments, joe.hershberger at ni.com
+ *
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd at denx.de.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+#include <hash.h>
+
+static int do_hash(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+#ifdef CONFIG_HASH_VERIFY
+	int verify = 0;
+
+	if (!strcmp(argv[1], "-v")) {
+		verify = 1;
+		argc--;
+		argv++;
+	}
+#endif
+	/* Move forward to 'algorithm' parameter */
+	argc--;
+	argv++;
+	return hash_command(*argv, verify, cmdtp, flag, argc - 1, argv + 1);
+}
+
+#ifdef CONFIG_HASH_VERIFY
+U_BOOT_CMD(
+	hash,	6,	1,	do_hash,
+	"compute hash message digest",
+	"algorithm address count [[*]sum_dest]\n"
+		"    - compute message digest [save to env var / *address]\n"
+	"hash -v algorithm address count [*]sum\n"
+		"    - verify hash of memory area with env var / *address"
+);
+#else
+U_BOOT_CMD(
+	hash,	5,	1,	do_hash,
+	"compute message digest",
+	"algorithm address count [[*]sum_dest]\n"
+		"    - compute message digest [save to env var / *address]"
+);
+#endif
diff --git a/include/config_cmd_all.h b/include/config_cmd_all.h
index 148d676..124d51f 100644
--- a/include/config_cmd_all.h
+++ b/include/config_cmd_all.h
@@ -41,6 +41,7 @@
 #define CONFIG_CMD_FLASH	/* flinfo, erase, protect	*/
 #define CONFIG_CMD_FPGA		/* FPGA configuration Support	*/
 #define CONFIG_CMD_GETTIME	/* Get time since boot         */
+#define CONFIG_CMD_HASH		/* calculate hash / digest	*/
 #define CONFIG_CMD_HWFLOW	/* RTS/CTS hw flow control	*/
 #define CONFIG_CMD_I2C		/* I2C serial bus support	*/
 #define CONFIG_CMD_IDE		/* IDE harddisk support		*/
-- 
1.7.7.3