libsodium/demos/generichashstream.c
2015-05-27 20:02:20 +02:00

61 lines
1.5 KiB
C

/*
* GraxRabble
* Demo programs for libsodium.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sodium.h> /* library header */
#include "utils.h" /* utility functions shared by demos */
/*
* Streaming variant of generic hash. This has the ability to hash
* data in chunks at a time and compute the same result as hashing
* all of the data at once.
*/
void
generichashstream(void)
{
unsigned char k[crypto_generichash_KEYBYTES_MAX]; /* key */
unsigned char h[crypto_generichash_BYTES_MIN]; /* hash output */
crypto_generichash_state state; /* hash stream */
unsigned char m[MAX_INPUT_SIZE]; /* input buffer */
size_t mlen; /* input length */
puts("Example: crypto_generichashstream\n");
prompt_input("a key", (char*)k, sizeof k, 0);
putchar('\n');
printf("Hashing message with %s\n", crypto_generichash_primitive());
/* initialize the stream */
crypto_generichash_init(&state, k, sizeof k, sizeof h);
for(;;) {
mlen = prompt_input("the next part of the message", (char*)m, sizeof m);
if (mlen == 0)
break;
/* keep appending data */
crypto_generichash_update(&state, m, mlen);
}
crypto_generichash_final(&state, h, sizeof h);
putchar('\n');
fputs("Hash: ", stdout);
print_hex(h, sizeof h);
putchar('\n');
}
int
main(void)
{
init();
generichashstream();
return 0;
}