Roll CRC16-CCITT into the hash infrastructure
The CRC16-CCITT checksum function is useful for space-constrained
applications (such as obtaining a checksum across a 2KBit or 4KBit
EEPROM) in boot applications. It has not been accessible from boot
scripts until now (due to not having a dedicated command and not being
supported by the hash infrstructure) limiting its applicability
outside of custom commands.
This adds the CRC16-CCITT (poly 0x1021, init 0x0) algorithm to the
list of available hashes and adds a new crc16_ccitt_wd_buf() to make
this possible.
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
[trini: Fix building crc16.o for SPL/TPL]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/common/hash.c b/common/hash.c
index ef14651..413a5bf 100644
--- a/common/hash.c
+++ b/common/hash.c
@@ -85,6 +85,33 @@
}
#endif
+static int hash_init_crc16_ccitt(struct hash_algo *algo, void **ctxp)
+{
+ uint16_t *ctx = malloc(sizeof(uint16_t));
+ *ctx = 0;
+ *ctxp = ctx;
+ return 0;
+}
+
+static int hash_update_crc16_ccitt(struct hash_algo *algo, void *ctx,
+ const void *buf, unsigned int size,
+ int is_last)
+{
+ *((uint16_t *)ctx) = crc16_ccitt(*((uint16_t *)ctx), buf, size);
+ return 0;
+}
+
+static int hash_finish_crc16_ccitt(struct hash_algo *algo, void *ctx,
+ void *dest_buf, int size)
+{
+ if (size < algo->digest_size)
+ return -1;
+
+ *((uint16_t *)dest_buf) = *((uint16_t *)ctx);
+ free(ctx);
+ return 0;
+}
+
static int hash_init_crc32(struct hash_algo *algo, void **ctxp)
{
uint32_t *ctx = malloc(sizeof(uint32_t));
@@ -160,6 +187,15 @@
},
#endif
{
+ .name = "crc16-ccitt",
+ .digest_size = 2,
+ .chunk_size = CHUNKSZ,
+ .hash_func_ws = crc16_ccitt_wd_buf,
+ .hash_init = hash_init_crc16_ccitt,
+ .hash_update = hash_update_crc16_ccitt,
+ .hash_finish = hash_finish_crc16_ccitt,
+ },
+ {
.name = "crc32",
.digest_size = 4,
.chunk_size = CHUNKSZ_CRC32,