1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis */
2 /* SPDX-License-Identifier: Unlicense */
3
4 /* The implementation is based on:
5 * Public Domain poly1305 from Andrew Moon
6 * https://github.com/floodyberry/poly1305-donna
7 */
8
9 #include "tomcrypt_private.h"
10 #include <stdarg.h>
11
12 #ifdef LTC_POLY1305
13
14 /**
15 POLY1305 multiple blocks of memory to produce the authentication tag
16 @param key The secret key
17 @param keylen The length of the secret key (octets)
18 @param mac [out] Destination of the authentication tag
19 @param maclen [in/out] Max size and resulting size of authentication tag
20 @param in The data to POLY1305
21 @param inlen The length of the data to POLY1305 (octets)
22 @param ... tuples of (data,len) pairs to POLY1305, terminated with a (NULL,x) (x=don't care)
23 @return CRYPT_OK if successful
24 */
poly1305_memory_multi(const unsigned char * key,unsigned long keylen,unsigned char * mac,unsigned long * maclen,const unsigned char * in,unsigned long inlen,...)25 int poly1305_memory_multi(const unsigned char *key, unsigned long keylen, unsigned char *mac, unsigned long *maclen, const unsigned char *in, unsigned long inlen, ...)
26 {
27 poly1305_state st;
28 int err;
29 va_list args;
30 const unsigned char *curptr;
31 unsigned long curlen;
32
33 LTC_ARGCHK(key != NULL);
34 LTC_ARGCHK(in != NULL);
35 LTC_ARGCHK(mac != NULL);
36 LTC_ARGCHK(maclen != NULL);
37
38 va_start(args, inlen);
39 curptr = in;
40 curlen = inlen;
41 if ((err = poly1305_init(&st, key, keylen)) != CRYPT_OK) { goto LBL_ERR; }
42 for (;;) {
43 if ((err = poly1305_process(&st, curptr, curlen)) != CRYPT_OK) { goto LBL_ERR; }
44 curptr = va_arg(args, const unsigned char*);
45 if (curptr == NULL) break;
46 curlen = va_arg(args, unsigned long);
47 }
48 err = poly1305_done(&st, mac, maclen);
49 LBL_ERR:
50 #ifdef LTC_CLEAN_STACK
51 zeromem(&st, sizeof(poly1305_state));
52 #endif
53 va_end(args);
54 return err;
55 }
56
57 #endif
58