/**
* generate HIP keying material
* @param kij Diffie-Hellman Kij (as in the HIP drafts)
* @param kij_len the length of the Kij material
* @param keymat pointer to a keymat structure which will be updated according
* to the generated keymaterial
* @param dstbuf the generated keymaterial will be written here
* @param dstbuflen the length of the buffer to which to write to
* @param hit1 source HIT
* @param hit2 destination HIT
* @param calc_index where the one byte index is stored (n of Kn)
* @param I the I value
* @param J the J value
*
*/
void hip_make_keymat(char *kij,
size_t kij_len,
struct hip_keymat_keymat *keymat,
void *dstbuf,
size_t dstbuflen,
struct in6_addr *hit1,
struct in6_addr *hit2,
uint8_t *calc_index,
const uint8_t I[PUZZLE_LENGTH],
const uint8_t J[PUZZLE_LENGTH])
{
int bufsize;
uint8_t index_nbr = 1;
size_t dstoffset = 0;
void *seedkey;
struct in6_addr *smaller_hit, *bigger_hit;
int hit1_is_bigger;
uint8_t *shabuffer = NULL;
HIP_DEBUG("\n");
if (dstbuflen < HIP_AH_SHA_LEN) {
HIP_ERROR("dstbuf is too short (%d)\n", dstbuflen);
return;
}
HIP_ASSERT(sizeof(index_nbr) == HIP_KEYMAT_INDEX_NBR_SIZE);
hit1_is_bigger = hip_hit_is_bigger(hit1, hit2);
bigger_hit = hit1_is_bigger ? hit1 : hit2;
smaller_hit = hit1_is_bigger ? hit2 : hit1;
shabuffer = hip_create_keymat_buffer(kij, kij_len, HIP_AH_SHA_LEN,
smaller_hit, bigger_hit, I, J);
if (!shabuffer) {
HIP_ERROR("No memory for keymat\n");
return;
}
bufsize = kij_len + 2 * sizeof(struct in6_addr) +
2 * sizeof(uint64_t) + 1;
// XX FIXME: is this correct
hip_build_digest(HIP_DIGEST_SHA1, shabuffer, bufsize, dstbuf);
dstoffset = HIP_AH_SHA_LEN;
index_nbr++;
/*
* K2 = SHA1(Kij | K1 | 2)
* K3 = SHA1(Kij | K2 | 3)
* ...
*/
seedkey = dstbuf;
hip_update_keymat_buffer(shabuffer, seedkey, HIP_AH_SHA_LEN,
kij_len, index_nbr);
while (dstoffset < dstbuflen) {
hip_build_digest(HIP_DIGEST_SHA1, shabuffer,
kij_len + HIP_AH_SHA_LEN + 1,
(uint8_t *) dstbuf + dstoffset);
seedkey = (uint8_t *) dstbuf + dstoffset;
dstoffset += HIP_AH_SHA_LEN;
index_nbr++;
hip_update_keymat_buffer(shabuffer, seedkey, HIP_AH_SHA_LEN,
kij_len, index_nbr);
}
keymat->offset = 0;
keymat->keymatlen = dstoffset;
keymat->keymatdst = dstbuf;
if (calc_index) {
*calc_index = index_nbr;
} else {
HIP_ERROR("NULL calc_index\n");
}
free(shabuffer);
}
/**
* hip_make_keymat - generate HIP keying material
* @param kij Diffie-Hellman Kij (as in the HIP drafts)
* @param kij_len the length of the Kij material
* @param keymat pointer to a keymat structure which will be updated according
* to the generated keymaterial
* @param dstbuf the generated keymaterial will be written here
* @param hit1 source HIT
* @param hit2 destination HIT
* @param calc_index where the one byte index is stored (n of Kn)
*
*/
void hip_make_keymat(char *kij, size_t kij_len,
struct hip_keymat_keymat *keymat,
void *dstbuf, size_t dstbuflen, struct in6_addr *hit1,
struct in6_addr *hit2, u8 *calc_index,
uint64_t I, uint64_t J)
{
int bufsize, err = 0;
uint8_t index_nbr = 1;
int dstoffset = 0;
void *seedkey;
struct in6_addr *smaller_hit, *bigger_hit;
int hit1_is_bigger;
u8 *shabuffer = NULL;
HIP_DEBUG("\n");
if (dstbuflen < HIP_AH_SHA_LEN) {
HIP_ERROR("dstbuf is too short (%d)\n", dstbuflen);
return;
}
_HIP_ASSERT(dstbuflen % 32 == 0);
HIP_ASSERT(sizeof(index_nbr) == HIP_KEYMAT_INDEX_NBR_SIZE);
hit1_is_bigger = hip_hit_is_bigger(hit1, hit2);
bigger_hit = hit1_is_bigger ? hit1 : hit2;
smaller_hit = hit1_is_bigger ? hit2 : hit1;
_HIP_HEXDUMP("kij", kij, kij_len);
_HIP_DEBUG("I=0x%llx J=0x%llx\n", I, J);
_HIP_HEXDUMP("bigger hit", bigger_hit, 16);
_HIP_HEXDUMP("smaller hit", smaller_hit, 16);
_HIP_HEXDUMP("index_nbr", (char *) &index_nbr,
HIP_KEYMAT_INDEX_NBR_SIZE);
shabuffer = hip_create_keymat_buffer(kij, kij_len, HIP_AH_SHA_LEN,
smaller_hit, bigger_hit, I, J);
if (!shabuffer) {
HIP_ERROR("No memory for keymat\n");
return;
}
bufsize = kij_len + 2 * sizeof(struct in6_addr) +
2 * sizeof(uint64_t) + 1;
//bufsize = kij_len+2*sizeof(struct in6_addr)+ 1;
// XX FIXME: is this correct
hip_build_digest(HIP_DIGEST_SHA1, shabuffer, bufsize, dstbuf);
_HIP_HEXDUMP("keymat digest", dstbuf, HIP_AH_SHA_LEN);
dstoffset = HIP_AH_SHA_LEN;
index_nbr++;
/*
* K2 = SHA1(Kij | K1 | 2)
* K3 = SHA1(Kij | K2 | 3)
* ...
*/
seedkey = dstbuf;
hip_update_keymat_buffer(shabuffer, seedkey, HIP_AH_SHA_LEN,
kij_len, index_nbr);
while (dstoffset < dstbuflen) {
hip_build_digest(HIP_DIGEST_SHA1, shabuffer,
kij_len + HIP_AH_SHA_LEN + 1,
dstbuf + dstoffset);
seedkey = dstbuf + dstoffset;
dstoffset += HIP_AH_SHA_LEN;
index_nbr++;
hip_update_keymat_buffer(shabuffer, seedkey, HIP_AH_SHA_LEN,
kij_len, index_nbr);
}
keymat->offset = 0;
keymat->keymatlen = dstoffset;
keymat->keymatdst = dstbuf;
if (calc_index)
*calc_index = index_nbr;
else
HIP_ERROR("NULL calc_index\n");
_HIP_DEBUG("keymat index_nbr=%u\n", index_nbr);
_HIP_HEXDUMP("GENERATED KEYMAT: ", dstbuf, dstbuflen);
if (shabuffer)
HIP_FREE(shabuffer);
return;
}