openssh/xmss_hash.c

140 lines
3.3 KiB
C

#ifdef WITH_XMSS
/*
hash.c version 20160722
Andreas Hülsing
Joost Rijneveld
Public domain.
*/
#include "includes.h"
#include "xmss_hash_address.h"
#include "xmss_commons.h"
#include "xmss_hash.h"
#include <stddef.h>
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#include <stdio.h>
#include <string.h>
#include <openssl/sha.h>
#include <openssl/hmac.h>
#include <openssl/evp.h>
int core_hash_SHA2(unsigned char *, const unsigned int, const unsigned char *,
unsigned int, const unsigned char *, unsigned long long, unsigned int);
unsigned char* addr_to_byte(unsigned char *bytes, const uint32_t addr[8]){
#if IS_LITTLE_ENDIAN==1
int i = 0;
for(i=0;i<8;i++)
to_byte(bytes+i*4, addr[i],4);
return bytes;
#else
memcpy(bytes, addr, 32);
return bytes;
#endif
}
int core_hash_SHA2(unsigned char *out, const unsigned int type, const unsigned char *key, unsigned int keylen, const unsigned char *in, unsigned long long inlen, unsigned int n){
unsigned long long i = 0;
unsigned char buf[inlen + n + keylen];
// Input is (toByte(X, 32) || KEY || M)
// set toByte
to_byte(buf, type, n);
for (i=0; i < keylen; i++) {
buf[i+n] = key[i];
}
for (i=0; i < inlen; i++) {
buf[keylen + n + i] = in[i];
}
if (n == 32) {
SHA256(buf, inlen + keylen + n, out);
return 0;
}
else {
if (n == 64) {
SHA512(buf, inlen + keylen + n, out);
return 0;
}
}
return 1;
}
/**
* Implements PRF
*/
int prf(unsigned char *out, const unsigned char *in, const unsigned char *key, unsigned int keylen)
{
return core_hash_SHA2(out, 3, key, keylen, in, 32, keylen);
}
/*
* Implemts H_msg
*/
int h_msg(unsigned char *out, const unsigned char *in, unsigned long long inlen, const unsigned char *key, const unsigned int keylen, const unsigned int n)
{
if (keylen != 3*n){
// H_msg takes 3n-bit keys, but n does not match the keylength of keylen
return -1;
}
return core_hash_SHA2(out, 2, key, keylen, in, inlen, n);
}
/**
* We assume the left half is in in[0]...in[n-1]
*/
int hash_h(unsigned char *out, const unsigned char *in, const unsigned char *pub_seed, uint32_t addr[8], const unsigned int n)
{
unsigned char buf[2*n];
unsigned char key[n];
unsigned char bitmask[2*n];
unsigned char byte_addr[32];
unsigned int i;
setKeyAndMask(addr, 0);
addr_to_byte(byte_addr, addr);
prf(key, byte_addr, pub_seed, n);
// Use MSB order
setKeyAndMask(addr, 1);
addr_to_byte(byte_addr, addr);
prf(bitmask, byte_addr, pub_seed, n);
setKeyAndMask(addr, 2);
addr_to_byte(byte_addr, addr);
prf(bitmask+n, byte_addr, pub_seed, n);
for (i = 0; i < 2*n; i++) {
buf[i] = in[i] ^ bitmask[i];
}
return core_hash_SHA2(out, 1, key, n, buf, 2*n, n);
}
int hash_f(unsigned char *out, const unsigned char *in, const unsigned char *pub_seed, uint32_t addr[8], const unsigned int n)
{
unsigned char buf[n];
unsigned char key[n];
unsigned char bitmask[n];
unsigned char byte_addr[32];
unsigned int i;
setKeyAndMask(addr, 0);
addr_to_byte(byte_addr, addr);
prf(key, byte_addr, pub_seed, n);
setKeyAndMask(addr, 1);
addr_to_byte(byte_addr, addr);
prf(bitmask, byte_addr, pub_seed, n);
for (i = 0; i < n; i++) {
buf[i] = in[i] ^ bitmask[i];
}
return core_hash_SHA2(out, 0, key, n, buf, n, n);
}
#endif /* WITH_XMSS */