[U-Boot] [PATCH v4 4/6] new commands: uuid and guid - generate random unique identifier

[Przemyslaw Marczak]

Those commands basis on implementation of random UUID generator version 4
which is described in RFC4122. The same algorithm is used for generation
both ids but string representation is different as below.

char:  0        9    14   19   24         36
       xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
UUID:     be     be   be   be       be
GUID:     le     le   le   be       be

Commands usage:
- uuid <varname(optional)>
- guid <varname(optional)>

The result is saved in environment as a "varname" variable if argument is given,
if not then its printed.

New config:
- CONFIG_CMD_UUID

Signed-off-by: Przemyslaw Marczak <p.marczak at samsung.com>
Cc: Stephen Warren <swarren at nvidia.com>
Cc: Lukasz Majewski <l.majewski at samsung.com>
Cc: trini at ti.com

---
Changes v4:
- new commit
---
 README           |  2 +-
 include/common.h |  4 +++-
 lib/Makefile     |  2 ++
 lib/uuid.c       | 44 +++++++++++++++++++++++++++++++++++++++++++-
 4 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/README b/README
index 216f0c7..f69b94e 100644
--- a/README
+++ b/README
@@ -1012,7 +1012,7 @@ The following options need to be configured:
 		CONFIG_CMD_CDP		* Cisco Discover Protocol support
 		CONFIG_CMD_MFSL		* Microblaze FSL support
 		CONFIG_CMD_XIMG		  Load part of Multi Image
-
+		CONFIG_CMD_UUID		* Generate random UUID or GUID string
 
 		EXAMPLE: If you want all functions except of network
 		support you can write:
diff --git a/include/common.h b/include/common.h
index deb08f2..de748f1 100644
--- a/include/common.h
+++ b/include/common.h
@@ -831,7 +831,9 @@ char *	strmhz(char *buf, unsigned long hz);
 #if defined(CONFIG_RANDOM_MACADDR) || \
 	defined(CONFIG_BOOTP_RANDOM_DELAY) || \
 	defined(CONFIG_CMD_LINK_LOCAL) || \
-	defined(CONFIG_RANDOM_UUID)
+	defined(CONFIG_RANDOM_UUID) || \
+	defined(CONFIG_CMD_UUID)
+
 #define RAND_MAX -1U
 void srand(unsigned int seed);
 unsigned int rand(void);
diff --git a/lib/Makefile b/lib/Makefile
index fd75e80..b85c825 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -65,6 +65,8 @@ obj-$(CONFIG_PARTITION_UUIDS) += uuid.o
 obj-y += vsprintf.o
 obj-$(CONFIG_RANDOM_UUID) += uuid.o
 obj-$(CONFIG_RANDOM_UUID) += rand.o
+obj-$(CONFIG_CMD_UUID) += uuid.o
+obj-$(CONFIG_CMD_UUID) += rand.o
 obj-$(CONFIG_RANDOM_MACADDR) += rand.o
 obj-$(CONFIG_BOOTP_RANDOM_DELAY) += rand.o
 obj-$(CONFIG_CMD_LINK_LOCAL) += rand.o
diff --git a/lib/uuid.c b/lib/uuid.c
index d3ba60e..0112b03 100644
--- a/lib/uuid.c
+++ b/lib/uuid.c
@@ -4,6 +4,7 @@
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
+#include <common.h>
 #include <linux/ctype.h>
 #include <errno.h>
 #include <common.h>
@@ -172,7 +173,7 @@ void uuid_bin_to_str(unsigned char *uuid_bin, char *uuid_str,
  *
  * @param uuid_bin - pointer to allocated array [16B]. Output is in big endian.
 */
-#ifdef CONFIG_RANDOM_UUID
+#if defined(CONFIG_RANDOM_UUID) || defined(CONFIG_CMD_UUID)
 void gen_rand_uuid(unsigned char *uuid_bin)
 {
 	struct uuid uuid;
@@ -211,4 +212,45 @@ void gen_rand_uuid_str(char *uuid_str, uuid_str_t str_format)
 	/* Convert UUID bin to UUID or GUID formated STRING  */
 	uuid_bin_to_str(uuid_bin, uuid_str, str_format);
 }
+
+#ifdef CONFIG_CMD_UUID
+int do_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	char uuid[UUID_STR_LEN + 1];
+	uuid_str_t str_format;
+
+	if (!strcmp(argv[0], "uuid"))
+		str_format = UUID_STR_FORMAT_STD;
+	else
+		str_format = UUID_STR_FORMAT_GUID;
+
+	if (argc == 1) {
+		gen_rand_uuid_str(uuid, str_format);
+		printf("%s\n", uuid);
+	} else if (argc == 2) {
+		gen_rand_uuid_str(uuid, str_format);
+		setenv(argv[1], uuid);
+	} else {
+		return CMD_RET_USAGE;
+	}
+
+	return CMD_RET_SUCCESS;
+}
+
+U_BOOT_CMD(uuid, CONFIG_SYS_MAXARGS, 1, do_uuid,
+	"UUID - generate Universally Unique Identifier version 4",
+	"<varname(optional)>\n"
+	"Argument:\n"
+	"varname: for set result in a environment variable\n"
+	"e.g. uuid uuid_env"
+);
+
+U_BOOT_CMD(guid, CONFIG_SYS_MAXARGS, 1, do_uuid,
+	"GUID - generate Globally Unique Identifier based on UUID version 4",
+	"<varname(optional)>\n"
+	"Argument:\n"
+	"varname: for set result in a environment variable\n"
+	"e.g. guid guid_env"
+);
+#endif
 #endif
-- 
1.9.0