int ikev2_derive_auth_data(int prf_alg, const struct wpabuf *sign_msg,
const u8 *ID, size_t ID_len, u8 ID_type,
struct ikev2_keys *keys, int initiator,
const u8 *shared_secret, size_t shared_secret_len,
const u8 *nonce, size_t nonce_len,
const u8 *key_pad, size_t key_pad_len,
u8 *auth_data)
{
size_t sign_len, buf_len;
u8 *sign_data, *pos, *buf, hash[IKEV2_MAX_HASH_LEN];
const struct ikev2_prf_alg *prf;
const u8 *SK_p = initiator ? keys->SK_pi : keys->SK_pr;
prf = ikev2_get_prf(prf_alg);
if (sign_msg == NULL || ID == NULL || SK_p == NULL ||
shared_secret == NULL || nonce == NULL || prf == NULL)
return -1;
/* prf(SK_pi/r,IDi/r') */
buf_len = 4 + ID_len;
buf = os_zalloc(buf_len);
if (buf == NULL)
return -1;
buf[0] = ID_type;
os_memcpy(buf + 4, ID, ID_len);
if (ikev2_prf_hash(prf->id, SK_p, keys->SK_prf_len,
1, (const u8 **) &buf, &buf_len, hash) < 0) {
os_free(buf);
return -1;
}
os_free(buf);
/* sign_data = msg | Nr/i | prf(SK_pi/r,IDi/r') */
sign_len = wpabuf_len(sign_msg) + nonce_len + prf->hash_len;
sign_data = os_malloc(sign_len);
if (sign_data == NULL)
return -1;
pos = sign_data;
os_memcpy(pos, wpabuf_head(sign_msg), wpabuf_len(sign_msg));
pos += wpabuf_len(sign_msg);
os_memcpy(pos, nonce, nonce_len);
pos += nonce_len;
os_memcpy(pos, hash, prf->hash_len);
/* AUTH = prf(prf(Shared Secret, key pad, sign_data) */
if (ikev2_prf_hash(prf->id, shared_secret, shared_secret_len, 1,
&key_pad, &key_pad_len, hash) < 0 ||
ikev2_prf_hash(prf->id, hash, prf->hash_len, 1,
(const u8 **) &sign_data, &sign_len, auth_data) < 0)
{
os_free(sign_data);
return -1;
}
os_free(sign_data);
return 0;
}
int ikev2_prf_plus(int alg, const u8 *key, size_t key_len,
const u8 *data, size_t data_len,
u8 *out, size_t out_len)
{
u8 hash[IKEV2_MAX_HASH_LEN];
size_t hash_len;
u8 iter, *pos, *end;
const u8 *addr[3];
size_t len[3];
const struct ikev2_prf_alg *prf;
int res;
prf = ikev2_get_prf(alg);
if (prf == NULL)
return -1;
hash_len = prf->hash_len;
addr[0] = hash;
len[0] = hash_len;
addr[1] = data;
len[1] = data_len;
addr[2] = &iter;
len[2] = 1;
pos = out;
end = out + out_len;
iter = 1;
while (pos < end) {
size_t clen;
if (iter == 1)
res = ikev2_prf_hash(alg, key, key_len, 2, &addr[1],
&len[1], hash);
else
res = ikev2_prf_hash(alg, key, key_len, 3, addr, len,
hash);
if (res < 0)
return -1;
clen = hash_len;
if ((int) clen > end - pos)
clen = end - pos;
os_memcpy(pos, hash, clen);
pos += clen;
iter++;
}
return 0;
}
static int ikev2_derive_keys(struct ikev2_responder_data *data)
{
u8 *buf, *pos, *pad, skeyseed[IKEV2_MAX_HASH_LEN];
size_t buf_len, pad_len;
struct wpabuf *shared;
const struct ikev2_integ_alg *integ;
const struct ikev2_prf_alg *prf;
const struct ikev2_encr_alg *encr;
int ret;
const u8 *addr[2];
size_t len[2];
/* RFC 4306, Sect. 2.14 */
integ = ikev2_get_integ(data->proposal.integ);
prf = ikev2_get_prf(data->proposal.prf);
encr = ikev2_get_encr(data->proposal.encr);
if (integ == NULL || prf == NULL || encr == NULL) {
wpa_printf(MSG_INFO, "IKEV2: Unsupported proposal");
return -1;
}
shared = dh_derive_shared(data->i_dh_public, data->r_dh_private,
data->dh);
if (shared == NULL)
return -1;
/* Construct Ni | Nr | SPIi | SPIr */
buf_len = data->i_nonce_len + data->r_nonce_len + 2 * IKEV2_SPI_LEN;
buf = os_malloc(buf_len);
if (buf == NULL) {
wpabuf_free(shared);
return -1;
}
pos = buf;
os_memcpy(pos, data->i_nonce, data->i_nonce_len);
pos += data->i_nonce_len;
os_memcpy(pos, data->r_nonce, data->r_nonce_len);
pos += data->r_nonce_len;
os_memcpy(pos, data->i_spi, IKEV2_SPI_LEN);
pos += IKEV2_SPI_LEN;
os_memcpy(pos, data->r_spi, IKEV2_SPI_LEN);
#ifdef CCNS_PL
#if __BYTE_ORDER == __LITTLE_ENDIAN
{
int i;
u8 *tmp = pos - IKEV2_SPI_LEN;
/* Incorrect byte re-ordering on little endian hosts.. */
for (i = 0; i < IKEV2_SPI_LEN; i++)
*tmp++ = data->i_spi[IKEV2_SPI_LEN - 1 - i];
for (i = 0; i < IKEV2_SPI_LEN; i++)
*tmp++ = data->r_spi[IKEV2_SPI_LEN - 1 - i];
}
#endif
#endif /* CCNS_PL */
/* SKEYSEED = prf(Ni | Nr, g^ir) */
/* Use zero-padding per RFC 4306, Sect. 2.14 */
pad_len = data->dh->prime_len - wpabuf_len(shared);
#ifdef CCNS_PL
/* Shared secret is not zero-padded correctly */
pad_len = 0;
#endif /* CCNS_PL */
pad = os_zalloc(pad_len ? pad_len : 1);
if (pad == NULL) {
wpabuf_free(shared);
os_free(buf);
return -1;
}
addr[0] = pad;
len[0] = pad_len;
addr[1] = wpabuf_head(shared);
len[1] = wpabuf_len(shared);
if (ikev2_prf_hash(prf->id, buf, data->i_nonce_len + data->r_nonce_len,
2, addr, len, skeyseed) < 0) {
wpabuf_free(shared);
os_free(buf);
os_free(pad);
return -1;
}
os_free(pad);
wpabuf_free(shared);
/* DH parameters are not needed anymore, so free them */
wpabuf_free(data->i_dh_public);
data->i_dh_public = NULL;
wpabuf_free(data->r_dh_private);
data->r_dh_private = NULL;
wpa_hexdump_key(MSG_DEBUG, "IKEV2: SKEYSEED",
skeyseed, prf->hash_len);
ret = ikev2_derive_sk_keys(prf, integ, encr, skeyseed, buf, buf_len,
&data->keys);
os_free(buf);
return ret;
}
static int ikev2_derive_keys(struct ikev2_initiator_data *data)
{
u8 *buf, *pos, *pad, skeyseed[IKEV2_MAX_HASH_LEN];
size_t buf_len, pad_len;
struct wpabuf *shared;
const struct ikev2_integ_alg *integ;
const struct ikev2_prf_alg *prf;
const struct ikev2_encr_alg *encr;
int ret;
const u8 *addr[2];
size_t len[2];
/* RFC 4306, Sect. 2.14 */
integ = ikev2_get_integ(data->proposal.integ);
prf = ikev2_get_prf(data->proposal.prf);
encr = ikev2_get_encr(data->proposal.encr);
if (integ == NULL || prf == NULL || encr == NULL) {
asd_printf(ASD_DEFAULT,MSG_DEBUG, "IKEV2: Unsupported proposal");
return -1;
}
shared = dh_derive_shared(data->r_dh_public, data->i_dh_private,
data->dh);
if (shared == NULL)
return -1;
/* Construct Ni | Nr | SPIi | SPIr */
buf_len = data->i_nonce_len + data->r_nonce_len + 2 * IKEV2_SPI_LEN;
buf = os_zalloc(buf_len);
if (buf == NULL) {
wpabuf_free(shared);
return -1;
}
pos = buf;
os_memcpy(pos, data->i_nonce, data->i_nonce_len);
pos += data->i_nonce_len;
os_memcpy(pos, data->r_nonce, data->r_nonce_len);
pos += data->r_nonce_len;
os_memcpy(pos, data->i_spi, IKEV2_SPI_LEN);
pos += IKEV2_SPI_LEN;
os_memcpy(pos, data->r_spi, IKEV2_SPI_LEN);
/* SKEYSEED = prf(Ni | Nr, g^ir) */
/* Use zero-padding per RFC 4306, Sect. 2.14 */
pad_len = data->dh->prime_len - wpabuf_len(shared);
pad = os_zalloc(pad_len ? pad_len : 1);
if (pad == NULL) {
wpabuf_free(shared);
os_free(buf);
return -1;
}
addr[0] = pad;
len[0] = pad_len;
addr[1] = wpabuf_head(shared);
len[1] = wpabuf_len(shared);
if (ikev2_prf_hash(prf->id, buf, data->i_nonce_len + data->r_nonce_len,
2, addr, len, skeyseed) < 0) {
wpabuf_free(shared);
os_free(buf);
os_free(pad);
return -1;
}
os_free(pad);
wpabuf_free(shared);
/* DH parameters are not needed anymore, so free them */
wpabuf_free(data->r_dh_public);
data->r_dh_public = NULL;
wpabuf_free(data->i_dh_private);
data->i_dh_private = NULL;
wpa_hexdump_key(MSG_DEBUG, "IKEV2: SKEYSEED",
skeyseed, prf->hash_len);
ret = ikev2_derive_sk_keys(prf, integ, encr, skeyseed, buf, buf_len,
&data->keys);
os_free(buf);
return ret;
}
