#include "../prf.h"
#include "../ed25519/sha512.h"
-static void memxor(char *buf, char c, size_t len) {
- for(size_t i = 0; i < len; i++)
+static void memxor(uint8_t *buf, uint8_t c, size_t len) {
+ for(size_t i = 0; i < len; i++) {
buf[i] ^= c;
+ }
}
static const size_t mdlen = 64;
+static const size_t blklen = 128;
-static bool hmac_sha512(const char *key, size_t keylen, const char *msg, size_t msglen, char *out) {
- char tmp[2 * mdlen];
+static bool hmac_sha512(const uint8_t *key, size_t keylen, const uint8_t *msg, size_t msglen, uint8_t *out) {
+ uint8_t tmp[blklen + mdlen];
sha512_context md;
- if(keylen <= mdlen) {
+ if(keylen <= blklen) {
memcpy(tmp, key, keylen);
- memset(tmp + keylen, 0, mdlen - keylen);
+ memset(tmp + keylen, 0, blklen - keylen);
} else {
- if(sha512(key, keylen, tmp) != 0)
+ if(sha512(key, keylen, tmp) != 0) {
return false;
+ }
+
+ memset(tmp + mdlen, 0, blklen - mdlen);
}
- if(sha512_init(&md) != 0)
+ if(sha512_init(&md) != 0) {
return false;
+ }
// ipad
- memxor(tmp, 0x36, mdlen);
- if(sha512_update(&md, tmp, mdlen) != 0)
+ memxor(tmp, 0x36, blklen);
+
+ if(sha512_update(&md, tmp, blklen) != 0) {
return false;
+ }
// message
- if(sha512_update(&md, msg, msglen) != 0)
+ if(sha512_update(&md, msg, msglen) != 0) {
return false;
+ }
- if(sha512_final(&md, tmp + mdlen) != 0)
+ if(sha512_final(&md, tmp + blklen) != 0) {
return false;
+ }
// opad
- memxor(tmp, 0x36 ^ 0x5c, mdlen);
- if(sha512(tmp, sizeof tmp, out) != 0)
+ memxor(tmp, 0x36 ^ 0x5c, blklen);
+
+ if(sha512(tmp, sizeof(tmp), out) != 0) {
return false;
+ }
return true;
}
We use SHA512 instead of MD5 and SHA1.
*/
-bool prf(const char *secret, size_t secretlen, char *seed, size_t seedlen, char *out, size_t outlen) {
+bool prf(const uint8_t *secret, size_t secretlen, uint8_t *seed, size_t seedlen, uint8_t *out, size_t outlen) {
/* Data is what the "inner" HMAC function processes.
It consists of the previous HMAC result plus the seed.
*/
- char data[mdlen + seedlen];
+ uint8_t data[mdlen + seedlen];
memset(data, 0, mdlen);
memcpy(data + mdlen, seed, seedlen);
- char hash[mdlen];
+ uint8_t hash[mdlen];
while(outlen > 0) {
/* Inner HMAC */
- if(!hmac_sha512(data, sizeof data, secret, secretlen, data))
+ if(!hmac_sha512(secret, secretlen, data, sizeof(data), data)) {
return false;
+ }
/* Outer HMAC */
if(outlen >= mdlen) {
- if(!hmac_sha512(data, sizeof data, secret, secretlen, out))
+ if(!hmac_sha512(secret, secretlen, data, sizeof(data), out)) {
return false;
+ }
+
out += mdlen;
outlen -= mdlen;
} else {
- if(!hmac_sha512(data, sizeof data, secret, secretlen, hash))
+ if(!hmac_sha512(secret, secretlen, data, sizeof(data), hash)) {
return false;
+ }
+
memcpy(out, hash, outlen);
out += outlen;
outlen = 0;