X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Fsiphash%2F_info;fp=ccan%2Fsiphash%2F_info;h=e6d518aa40bf533edbfadfa9819ee28a3a494672;hp=0000000000000000000000000000000000000000;hb=480b3117c39b91fcb6d39c60222232b7608f5507;hpb=6bab11a210f123033225553057e24e68b99a8afd

diff --git a/ccan/siphash/_info b/ccan/siphash/_info
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+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * siphash - a keyed hash function
+ *
+ * SipHash-c-d, where `c` is the number of rounds per message chunk
+ *              and `d` the number of finalization rounds,
+ * "is a family of pseudorandom functions optimized for speed on short
+ * messages"
+ *
+ * Implemented from the paper https://131002.net/siphash/
+ * The designers recommend using SipHash-2-4 or SipHash-4-8
+ *
+ * SipHash-c-d uses a 16-byte key.
+ * To defend against hash-flooding, the application needs to use
+ * a new random key regularly.
+ *
+ * The designers of SipHash claim it is cryptographically strong
+ * to use as MAC with secret key but _not_collision_resistant_.
+ *
+ * Returns one 64-bit word as the hash function result.
+ *
+ * Example:
+ *	// Outputs "cf2794e0277187b7"
+ *	#include <stdio.h>
+ *	#include <ccan/siphash/siphash.h>
+ *
+ *	int main(void)
+ *	{
+ * 		unsigned char t_key[16] =
+ *			{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
+ *		unsigned char data[4] = "\0\1\2\3";
+ *		uint64_t hash = siphash_2_4(data, sizeof(data), t_key);
+ *		printf("%llx\n", (unsigned long long)hash);
+ *
+ *		return 0;
+ *	}
+ *
+ *
+ * License: GPL (v2 or any later version)
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/endian\n");
+		return 0;
+	}
+
+	return 1;
+}