@@ -815,6 +815,8 @@ void udelay (unsigned long);
void mdelay(unsigned long);
/* lib/uuid.c */
+void gen_rand_uuid(unsigned char *uuid_bin);
+void gen_rand_uuid_str(char *uuid_str);
void uuid_bin_to_str(unsigned char *uuid, char *str);
int uuid_str_to_bin(char *uuid, unsigned char *out);
int uuid_str_valid(const char *uuid);
@@ -831,7 +833,8 @@ char * strmhz(char *buf, unsigned long hz);
/* lib/rand.c */
#if defined(CONFIG_RANDOM_MACADDR) || \
defined(CONFIG_BOOTP_RANDOM_DELAY) || \
- defined(CONFIG_CMD_LINK_LOCAL)
+ defined(CONFIG_CMD_LINK_LOCAL) || \
+ defined(CONFIG_RANDOM_UUID)
#define RAND_MAX -1U
void srand(unsigned int seed);
unsigned int rand(void);
@@ -62,7 +62,10 @@ obj-y += time.o
obj-$(CONFIG_TRACE) += trace.o
obj-$(CONFIG_BOOTP_PXE) += uuid.o
obj-$(CONFIG_PARTITION_UUIDS) += uuid.o
+obj-$(CONFIG_PARTITION_UUIDS) += rand.o
obj-y += vsprintf.o
+obj-$(CONFIG_RANDOM_UUID) += uuid.o
+obj-$(CONFIG_RANDOM_UUID) += rand.o
obj-$(CONFIG_RANDOM_MACADDR) += rand.o
obj-$(CONFIG_BOOTP_RANDOM_DELAY) += rand.o
obj-$(CONFIG_CMD_LINK_LOCAL) += rand.o
@@ -7,8 +7,30 @@
#include <linux/ctype.h>
#include <errno.h>
#include <common.h>
+#include <asm/io.h>
+#include <part_efi.h>
+#include <malloc.h>
#define UUID_STR_LEN 36
+#define UUID_BIN_LEN 16
+
+#define UUID_VERSION_MASK 0xf000
+#define UUID_VERSION_SHIFT 12
+#define UUID_VERSION 0x4
+
+#define UUID_VARIANT_MASK 0xc0
+#define UUID_VARIANT_SHIFT 7
+#define UUID_VARIANT 0x1
+
+/* This is structure is in big-endian */
+struct uuid {
+ unsigned int time_low;
+ unsigned short time_mid;
+ unsigned short time_hi_and_version;
+ unsigned char clock_seq_hi_and_reserved;
+ unsigned char clock_seq_low;
+ unsigned char node[6];
+} __packed;
/*
* This is what a UUID string looks like.
@@ -21,7 +43,6 @@
* xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
* le le le be be
*/
-
int uuid_str_valid(const char *uuid)
{
int i, valid;
@@ -95,3 +116,58 @@ void uuid_bin_to_str(unsigned char *uuid, char *str)
}
}
}
+
+/*
+ * gen_rand_uuid() - this function generates a random binary UUID v4 and stores
+ * it into the memory pointed at by the supplied pointer,
+ * which must be 16 bytes in size
+ *
+ * Layout of UUID Version 4:
+ * timestamp - 60-bit: time_low, time_mid, time_hi_and_version
+ * version - 4 bit (bit 4 through 7 of the time_hi_and_version)
+ * clock seq - 14 bit: clock_seq_hi_and_reserved, clock_seq_low
+ * variant: - bit 6 and 7 of clock_seq_hi_and_reserved
+ * node - 48 bit
+ * In this version all fields beside 4 bit version are randomly generated.
+ * source: https://www.ietf.org/rfc/rfc4122.txt
+ *
+ * @param uuid_bin pointer to 16 bytes len array
+*/
+#ifdef CONFIG_RANDOM_UUID
+void gen_rand_uuid(unsigned char *uuid_bin)
+{
+ struct uuid uuid;
+ unsigned int *ptr = (unsigned int *)&uuid;
+ int i;
+
+ /* Set all fields randomly */
+ for (i = 0; i < sizeof(struct uuid) / sizeof(*ptr); i++)
+ *(ptr + i) = cpu_to_be32(rand());
+
+ clrsetbits_be16(&uuid.time_hi_and_version,
+ UUID_VERSION_MASK,
+ UUID_VERSION << UUID_VERSION_SHIFT);
+
+ clrsetbits_8(&uuid.clock_seq_hi_and_reserved,
+ UUID_VARIANT_MASK,
+ UUID_VARIANT << UUID_VARIANT_SHIFT);
+
+ memcpy(uuid_bin, &uuid, sizeof(struct uuid));
+}
+
+/*
+ * gen_rand_uuid_str() - this function generates a random string formatted
+ * UUID v4 and stores it into the memory pointed at by
+ * the supplied pointer, which must be 37 bytes in size
+ *
+ * @param uuid_str pointer to 37 bytes len array
+ */
+void gen_rand_uuid_str(char *uuid_str)
+{
+ unsigned char uuid_bin[UUID_BIN_LEN];
+
+ gen_rand_uuid(uuid_bin);
+
+ uuid_bin_to_str(uuid_bin, uuid_str);
+}
+#endif
This patch adds support to generate UUID (Universally Unique Identifier) in version 4 based on RFC4122, which is randomly. Source: https://www.ietf.org/rfc/rfc4122.txt Changes: - add new config: CONFIG_RANDOM_UUID: compile uuid.c and rand.c lib/uuid.c: - add gen_rand_uuid() - this function writes 16 bytes len binary representation UUID v4 to the memory at given address. - add gen_rand_uuid_str() - this function writes 37 bytes len hexadecimal ASCII string representation of UUID v4 to the memory at given address. Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com> Cc: Jason Hobbs <jason.hobbs@calxeda.com> Cc: Stephen Warren <swarren@nvidia.com> Cc: Lukasz Majewski <l.majewski@samsung.com> Cc: trini@ti.com --- Changes v2: - put uuid generation changes in a separate commit - get_uuid_str() - change name to gen_rand_uuid_str() - add new function: gen_rand_uuid() - remove unnecessary '\0' at the end of uuid string - drop unnecessary error checking - functions now takes pointers to allocated memory instead of alloc it itself - add new config option: CONFIG_RANDOM_UUID Changes v3: - remove unused UUID_STR_BYTE_LEN - reword comments - remove null pointer checking from gen_rand_uuid() and gen_rand_uuid_str() - remove unneeded memset from gen_rand_uuid() - undo moving vsprintf.o object in lib/Makefile - add attribute "packed" to the uuid structure - gen_rand_uuid(): add endian functions for modify uuid data - gen_rand_uuid(): use memcpy() to store uuid data into given buffer for avoid unaligned access issues - change uuid version and variant masks to proper for use with clrsetbits_* - add #ifdef CONFIG_RANDOM_UUID to random uuid code for avoid warnings --- include/common.h | 5 +++- lib/Makefile | 3 +++ lib/uuid.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 84 insertions(+), 2 deletions(-)