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-rw-r--r--src/util/crypto_crc.c30
1 files changed, 30 insertions, 0 deletions
diff --git a/src/util/crypto_crc.c b/src/util/crypto_crc.c
index ec2e80683..b5df01959 100644
--- a/src/util/crypto_crc.c
+++ b/src/util/crypto_crc.c
@@ -165,5 +165,35 @@ GNUNET_CRYPTO_crc16_n (const void *buf, size_t len)
}
+/**
+ * @ingroup hash
+ * Calculate the checksum of a buffer in one step.
+ *
+ * @param buf buffer to calculate CRC over
+ * @param len number of bytes in @a buf
+ * @return crc8 value
+ */
+uint8_t
+GNUNET_CRYPTO_crc8_n (const void *buf,
+ size_t len)
+{
+ const uint8_t *data = buf;
+ unsigned int crc = 0;
+ int i;
+ int j;
+
+ for (j = len; 0 != j; j--)
+ {
+ crc ^= (*data++ << 8);
+ for (i = 8; 0 != i; i--)
+ {
+ if (0 != (crc & 0x8000))
+ crc ^= (0x1070 << 3);
+ crc <<= 1;
+ }
+ }
+ return (uint8_t) (crc >> 8);
+}
+
/* end of crypto_crc.c */