sae: Add basic H2E support
This commit is contained in:
Denis Kenzior
parent
d12ac0fa71
commit
891b78e9e8
502
src/sae.c
502
src/sae.c
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@ -35,6 +35,9 @@
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#include "src/sae.h"
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#include "src/auth-proto.h"
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/* SHA-512 is the highest supported hashing function as of 802.11-2020 */
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#define SAE_MAX_HASH_LEN 64
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#define SAE_RETRANSMIT_TIMEOUT 2
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#define SAE_SYNC_MAX 3
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#define SAE_MAX_ASSOC_RETRY 3
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@ -53,15 +56,15 @@ struct sae_sm {
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enum sae_state state;
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const struct l_ecc_curve *curve;
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unsigned int group;
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uint8_t group_retry;
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const unsigned int *ecc_groups;
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int group_retry;
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uint16_t *rejected_groups;
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struct l_ecc_scalar *rand;
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struct l_ecc_scalar *scalar;
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struct l_ecc_scalar *p_scalar;
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struct l_ecc_point *element;
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struct l_ecc_point *p_element;
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uint16_t send_confirm;
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uint8_t kck[32];
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uint8_t kck[SAE_MAX_HASH_LEN];
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uint8_t pmk[32];
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uint8_t pmkid[16];
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uint8_t *token;
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@ -79,8 +82,83 @@ struct sae_sm {
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sae_tx_authenticate_func_t tx_auth;
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sae_tx_associate_func_t tx_assoc;
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void *user_data;
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enum crypto_sae sae_type;
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};
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static enum mmpdu_status_code sae_status_code(struct sae_sm *sm)
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{
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switch (sm->sae_type) {
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case CRYPTO_SAE_LOOPING:
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return MMPDU_STATUS_CODE_SUCCESS;
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case CRYPTO_SAE_HASH_TO_ELEMENT:
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return MMPDU_STATUS_CODE_SAE_HASH_TO_ELEMENT;
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}
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return MMPDU_STATUS_CODE_UNSPECIFIED;
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}
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static void sae_rejected_groups_append(struct sae_sm *sm, uint16_t group)
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{
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uint16_t i;
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if (!sm->rejected_groups) {
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sm->rejected_groups = reallocarray(NULL, 2, sizeof(uint16_t));
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sm->rejected_groups[0] = 1;
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sm->rejected_groups[1] = group;
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return;
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}
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for (i = 1; i <= sm->rejected_groups[0]; i++)
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if (sm->rejected_groups[i] == group)
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return;
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sm->rejected_groups = reallocarray(sm->rejected_groups,
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i + 1, sizeof(uint16_t));
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sm->rejected_groups[0] += 1;
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sm->rejected_groups[i] = group;
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}
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static void sae_reset_state(struct sae_sm *sm)
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{
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l_free(sm->token);
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sm->token = NULL;
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l_ecc_scalar_free(sm->scalar);
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sm->scalar = NULL;
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l_ecc_scalar_free(sm->p_scalar);
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sm->p_scalar = NULL;
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l_ecc_scalar_free(sm->rand);
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sm->rand = NULL;
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l_ecc_point_free(sm->element);
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sm->element = NULL;
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l_ecc_point_free(sm->p_element);
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sm->p_element = NULL;
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l_ecc_point_free(sm->pwe);
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sm->pwe = NULL;
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}
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static int sae_choose_next_group(struct sae_sm *sm)
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{
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const unsigned int *ecc_groups = l_ecc_supported_ike_groups();
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bool reset = sm->group_retry >= 0;
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do {
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sm->group_retry++;
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if (ecc_groups[sm->group_retry] == 0)
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return -ENOENT;
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} while (sm->sae_type != CRYPTO_SAE_LOOPING &&
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!sm->handshake->ecc_sae_pts[sm->group_retry]);
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if (reset)
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sae_reset_state(sm);
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sm->group = ecc_groups[sm->group_retry];
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sm->curve = l_ecc_curve_from_ike_group(sm->group);
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return 0;
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}
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static bool sae_pwd_seed(const uint8_t *addr1, const uint8_t *addr2,
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uint8_t *base, size_t base_len,
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uint8_t counter, uint8_t *out)
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@ -145,22 +223,26 @@ static struct l_ecc_scalar *sae_pwd_value(const struct l_ecc_curve *curve,
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}
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/* IEEE 802.11-2016 - Section 12.4.2 Assumptions on SAE */
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static bool sae_cn(const uint8_t *kck, uint16_t send_confirm,
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static ssize_t sae_cn(struct sae_sm *sm, uint16_t send_confirm,
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struct l_ecc_scalar *scalar1,
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struct l_ecc_point *element1,
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struct l_ecc_scalar *scalar2,
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struct l_ecc_point *element2,
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uint8_t *confirm)
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{
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enum l_checksum_type hash =
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crypto_sae_hash_from_ecc_prime_len(sm->sae_type,
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l_ecc_curve_get_scalar_bytes(sm->curve));
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size_t hash_len = l_checksum_digest_length(hash);
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uint8_t s1[L_ECC_SCALAR_MAX_BYTES];
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uint8_t s2[L_ECC_SCALAR_MAX_BYTES];
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uint8_t e1[L_ECC_POINT_MAX_BYTES];
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uint8_t e2[L_ECC_POINT_MAX_BYTES];
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struct l_checksum *hmac;
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struct iovec iov[5];
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int ret;
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ssize_t ret;
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hmac = l_checksum_new_hmac(L_CHECKSUM_SHA256, kck, 32);
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hmac = l_checksum_new_hmac(hash, sm->kck, hash_len);
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if (!hmac)
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return false;
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@ -178,12 +260,10 @@ static bool sae_cn(const uint8_t *kck, uint16_t send_confirm,
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iov[4].iov_len = l_ecc_point_get_data(element2, e2, sizeof(e2));
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l_checksum_updatev(hmac, iov, 5);
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ret = l_checksum_get_digest(hmac, confirm, 32);
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ret = l_checksum_get_digest(hmac, confirm, hash_len);
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l_checksum_free(hmac);
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return (ret == 32);
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return ret;
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}
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static int sae_reject(struct sae_sm *sm, uint16_t transaction, uint16_t status)
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@ -382,28 +462,36 @@ static struct l_ecc_point *sae_compute_pwe(const struct l_ecc_curve *curve,
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return pwe;
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}
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static bool sae_build_commit(struct sae_sm *sm, const uint8_t *addr1,
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static int sae_build_commit(struct sae_sm *sm, const uint8_t *addr1,
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const uint8_t *addr2, uint8_t *commit,
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size_t *len, bool retry)
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size_t len, bool retry)
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{
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struct l_ecc_scalar *mask;
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uint8_t *ptr = commit;
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struct l_ecc_scalar *order;
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struct ie_tlv_builder builder;
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if (retry)
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goto old_commit;
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if (!sm->handshake->passphrase) {
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l_error("no handshake passphrase found");
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return false;
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}
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switch (sm->sae_type) {
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case CRYPTO_SAE_HASH_TO_ELEMENT:
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{
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const struct l_ecc_point *pt =
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sm->handshake->ecc_sae_pts[sm->group_retry];
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sm->pwe = sae_compute_pwe(sm->curve, sm->handshake->passphrase,
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sm->pwe = crypto_derive_sae_pwe_from_pt_ecc(addr1, addr2, pt);
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break;
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}
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case CRYPTO_SAE_LOOPING:
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sm->pwe = sae_compute_pwe(sm->curve, sm->handshake->passphrase,
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addr1, addr2);
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break;
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}
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if (!sm->pwe) {
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l_error("could not compute PWE");
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return false;
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return -EIO;
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}
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sm->scalar = l_ecc_scalar_new(sm->curve, NULL, 0);
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@ -431,17 +519,25 @@ static bool sae_build_commit(struct sae_sm *sm, const uint8_t *addr1,
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*/
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old_commit:
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/* transaction */
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/*
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* 12.4.7.4 Encoding and decoding of SAE Commit messages
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* Refer to Table 9-40 for order and Table 9-41 for presence
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* of elements
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*/
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/* "a Transaction Sequence Number of 1" */
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l_put_le16(1, ptr);
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ptr += 2;
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/* status success */
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l_put_le16(0, ptr);
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/* "a Status Code of SUCCESS or SAE_HASH_TO_ELEMENT" */
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l_put_le16(sae_status_code(sm), ptr);
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ptr += 2;
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/* group */
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l_put_le16(sm->group, ptr);
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ptr += 2;
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if (sm->token) {
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if (sm->sae_type == CRYPTO_SAE_LOOPING && sm->token) {
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memcpy(ptr, sm->token, sm->token_len);
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ptr += sm->token_len;
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}
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@ -449,23 +545,40 @@ old_commit:
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ptr += l_ecc_scalar_get_data(sm->scalar, ptr, L_ECC_SCALAR_MAX_BYTES);
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ptr += l_ecc_point_get_data(sm->element, ptr, L_ECC_POINT_MAX_BYTES);
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*len = ptr - commit;
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ie_tlv_builder_init(&builder, ptr, len - (ptr - commit));
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return true;
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if (sm->sae_type != CRYPTO_SAE_LOOPING && sm->rejected_groups) {
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ie_tlv_builder_next(&builder, IE_TYPE_REJECTED_GROUPS);
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ie_tlv_builder_set_data(&builder, sm->rejected_groups + 1,
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sm->rejected_groups[0] * sizeof(uint16_t));
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}
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if (sm->sae_type != CRYPTO_SAE_LOOPING && sm->token) {
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ie_tlv_builder_next(&builder,
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IE_TYPE_ANTI_CLOGGING_TOKEN_CONTAINER);
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ie_tlv_builder_set_data(&builder, sm->token, sm->token_len);
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}
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ie_tlv_builder_finalize(&builder, &len);
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return ptr - commit + len;
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}
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static void sae_send_confirm(struct sae_sm *sm)
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static bool sae_send_confirm(struct sae_sm *sm)
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{
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uint8_t confirm[32];
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uint8_t body[38];
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uint8_t confirm[SAE_MAX_HASH_LEN];
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uint8_t body[sizeof(confirm) + 6];
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uint8_t *ptr = body;
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ssize_t r;
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/*
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* confirm = CN(KCK, send-confirm, commit-scalar, COMMIT-ELEMENT,
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* peer-commit-scalar, PEER-COMMIT-ELEMENT)
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*/
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sae_cn(sm->kck, sm->sc, sm->scalar, sm->element, sm->p_scalar,
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r = sae_cn(sm, sm->sc, sm->scalar, sm->element, sm->p_scalar,
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sm->p_element, confirm);
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if (r < 0)
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return false;
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l_put_le16(2, ptr);
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ptr += 2;
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@ -473,26 +586,31 @@ static void sae_send_confirm(struct sae_sm *sm)
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ptr += 2;
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l_put_le16(sm->sc, ptr);
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ptr += 2;
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memcpy(ptr, confirm, 32);
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ptr += 32;
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memcpy(ptr, confirm, r);
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ptr += r;
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sm->tx_auth(body, 38, sm->user_data);
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sm->tx_auth(body, ptr - body, sm->user_data);
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return true;
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}
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static int sae_process_commit(struct sae_sm *sm, const uint8_t *from,
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const uint8_t *frame, size_t len)
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{
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uint8_t *ptr = (uint8_t *) frame;
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uint8_t k[L_ECC_SCALAR_MAX_BYTES];
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unsigned int nbytes = l_ecc_curve_get_scalar_bytes(sm->curve);
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enum l_checksum_type hash =
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crypto_sae_hash_from_ecc_prime_len(sm->sae_type, nbytes);
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size_t hash_len = l_checksum_digest_length(hash);
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struct l_ecc_point *k_point;
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uint8_t zero_key[32] = { 0 };
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uint8_t keyseed[32];
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uint8_t kck_and_pmk[2][32];
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uint8_t k[L_ECC_SCALAR_MAX_BYTES];
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ssize_t klen;
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const void *salt = NULL;
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size_t salt_len = 0;
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uint8_t keyseed[SAE_MAX_HASH_LEN];
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uint8_t kck_and_pmk[SAE_MAX_HASH_LEN + 32];
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uint8_t tmp[L_ECC_SCALAR_MAX_BYTES];
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struct l_ecc_scalar *tmp_scalar;
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ssize_t klen;
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struct l_ecc_scalar *order;
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unsigned int nbytes = l_ecc_curve_get_scalar_bytes(sm->curve);
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ptr += 2;
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@ -549,19 +667,46 @@ static int sae_process_commit(struct sae_sm *sm, const uint8_t *from,
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* i.e., if P = (x, y) then F(P) = x.
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*/
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klen = l_ecc_point_get_x(k_point, k, sizeof(k));
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l_ecc_point_free(k_point);
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if (klen < 0)
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return sae_reject(sm, SAE_STATE_COMMITTED,
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MMPDU_STATUS_CODE_UNSPECIFIED);
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/* keyseed = H(<0>32, k) */
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hmac_sha256(zero_key, 32, k, klen, keyseed, 32);
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/*
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* keyseed = H(salt, k)
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*
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* 802.11-2020 12.4.5.4:
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* Hash to Element case:
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* "... a salt consisting of the concatenation of the rejected groups
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* from each peer's Rejected Groups element shall be
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* passed to the KDF; those of the peer with the highest MAC address go
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* first (if only one sent a Rejected Groups element then the salt will
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* consist of that list). "
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*
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* Looping case:
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* "...the salt shall consist of a series of octets of the value zero
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* whose length equals the length of the digest of the hash function
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* used to instantiate H()."
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*
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* NOTE: We use hkdf_extract here since it is just an hmac invocation
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* and it handles the case of the zero key for us.
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*/
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if (sm->sae_type != CRYPTO_SAE_LOOPING && sm->rejected_groups) {
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salt = sm->rejected_groups + 1;
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salt_len = sm->rejected_groups[0] * sizeof(uint16_t);
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}
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hkdf_extract(hash, salt, salt_len, 1, keyseed, k, klen);
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/*
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* kck_and_pmk = KDF-Hash-512(keyseed, "SAE KCK and PMK",
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(commit-scalar + peer-commit-scalar) mod r)
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* context = (commit-scalar + peer-commit-scalar) mod r
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* Length = Q + 256
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* kck_and_pmk = KDF-Hash-Length(keyseed, "SAE KCK and PMK", context)
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* KCK = L(kck_and_pmk, 0, Q)
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* PMK = L(kck_and_pmk, Q, 256)
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*
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* Q is the length of the digest of the H(), the hash function used
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*/
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tmp_scalar = l_ecc_scalar_new(sm->curve, NULL, 0);
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order = l_ecc_curve_get_order(sm->curve);
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@ -569,11 +714,12 @@ static int sae_process_commit(struct sae_sm *sm, const uint8_t *from,
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l_ecc_scalar_add(tmp_scalar, sm->p_scalar, sm->scalar, order);
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l_ecc_scalar_get_data(tmp_scalar, tmp, sizeof(tmp));
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kdf_sha256(keyseed, 32, "SAE KCK and PMK", strlen("SAE KCK and PMK"),
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tmp, nbytes, kck_and_pmk, 64);
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crypto_kdf(hash, keyseed, hash_len,
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"SAE KCK and PMK", strlen("SAE KCK and PMK"),
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tmp, nbytes, kck_and_pmk, hash_len + 32);
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memcpy(sm->kck, kck_and_pmk[0], 32);
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memcpy(sm->pmk, kck_and_pmk[1], 32);
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memcpy(sm->kck, kck_and_pmk, hash_len);
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memcpy(sm->pmk, kck_and_pmk + hash_len, 32);
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/*
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* PMKID = L((commit-scalar + peer-commit-scalar) mod r, 0, 128)
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@ -587,7 +733,9 @@ static int sae_process_commit(struct sae_sm *sm, const uint8_t *from,
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/* don't set the handshakes pmkid until confirm is verified */
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memcpy(sm->pmkid, tmp, 16);
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sae_send_confirm(sm);
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if (!sae_send_confirm(sm))
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return -EPROTO;
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sm->state = SAE_STATE_CONFIRMED;
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return 0;
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@ -595,13 +743,16 @@ static int sae_process_commit(struct sae_sm *sm, const uint8_t *from,
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static bool sae_verify_confirm(struct sae_sm *sm, const uint8_t *frame)
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{
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uint8_t check[32];
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uint8_t check[SAE_MAX_HASH_LEN];
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uint16_t rc = l_get_le16(frame);
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ssize_t r;
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sae_cn(sm->kck, rc, sm->p_scalar, sm->p_element, sm->scalar,
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r = sae_cn(sm, rc, sm->p_scalar, sm->p_element, sm->scalar,
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sm->element, check);
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if (r < 0)
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return false;
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||||
if (memcmp(frame + 2, check, 32))
|
||||
if (memcmp(frame + 2, check, r))
|
||||
return false;
|
||||
|
||||
sm->rc = rc;
|
||||
|
|
@ -614,11 +765,6 @@ static int sae_process_confirm(struct sae_sm *sm, const uint8_t *from,
|
|||
{
|
||||
const uint8_t *ptr = frame;
|
||||
|
||||
if (len < 34) {
|
||||
l_error("bad length");
|
||||
return -EBADMSG;
|
||||
}
|
||||
|
||||
/*
|
||||
* If processing is unsuccessful and the SAE Confirm message is not
|
||||
* verified, protocol instance shall remain in Confirmed state.
|
||||
|
|
@ -647,14 +793,16 @@ static int sae_process_confirm(struct sae_sm *sm, const uint8_t *from,
|
|||
static bool sae_send_commit(struct sae_sm *sm, bool retry)
|
||||
{
|
||||
struct handshake_state *hs = sm->handshake;
|
||||
/* regular commit + possible 256 byte token + 6 bytes header */
|
||||
uint8_t commit[L_ECC_SCALAR_MAX_BYTES + L_ECC_POINT_MAX_BYTES + 262];
|
||||
size_t len;
|
||||
/* regular commit + 3x IEs (257 bytes) + 6 bytes header */
|
||||
uint8_t commit[L_ECC_SCALAR_MAX_BYTES + L_ECC_POINT_MAX_BYTES + 777];
|
||||
int r;
|
||||
|
||||
if (!sae_build_commit(sm, hs->spa, hs->aa, commit, &len, retry))
|
||||
r = sae_build_commit(sm, hs->spa, hs->aa,
|
||||
commit, sizeof(commit), retry);
|
||||
if (r < 0)
|
||||
return false;
|
||||
|
||||
sm->tx_auth(commit, len, sm->user_data);
|
||||
sm->tx_auth(commit, r, sm->user_data);
|
||||
|
||||
return true;
|
||||
}
|
||||
|
|
@ -681,9 +829,33 @@ static bool sae_assoc_timeout(struct auth_proto *ap)
|
|||
* sent. The new SAE Commit message shall be transmitted to the peer, Sync shall
|
||||
* be zeroed, and the t0 (retransmission) timer shall be set.
|
||||
*/
|
||||
static void sae_process_anti_clogging(struct sae_sm *sm, const uint8_t *ptr,
|
||||
static int sae_process_anti_clogging(struct sae_sm *sm, const uint8_t *ptr,
|
||||
size_t len)
|
||||
{
|
||||
if (len < 2)
|
||||
return -EBADMSG;
|
||||
|
||||
len -= 2;
|
||||
ptr += 2;
|
||||
|
||||
/*
|
||||
* 802.11-2020, Table 9-41:
|
||||
* When the hash-to-element method is used to derive the PWE, the
|
||||
* Anti-Clogging Token Container element is present if the
|
||||
* Status Code field is ANTI_CLOGGING_TOKEN_REQUIRED
|
||||
*/
|
||||
if (sm->sae_type != CRYPTO_SAE_LOOPING) {
|
||||
if (len < 3)
|
||||
return -EBADMSG;
|
||||
|
||||
if (ptr[0] != IE_TYPE_EXTENSION || ptr[2] != 93 ||
|
||||
ptr[1] < 2 || len < ptr[1] + 2u)
|
||||
return -EBADMSG;
|
||||
|
||||
len = ptr[1] - 1;
|
||||
ptr += 3;
|
||||
}
|
||||
|
||||
/*
|
||||
* IEEE 802.11-2016 - Section 12.4.6 Anti-clogging tokens
|
||||
*
|
||||
|
|
@ -694,16 +866,18 @@ static void sae_process_anti_clogging(struct sae_sm *sm, const uint8_t *ptr,
|
|||
* going to be 2 bytes less than the passed in length. This is why we
|
||||
* are checking 3 > len > 258.
|
||||
*/
|
||||
if (len < 3 || len > 258) {
|
||||
if (len < 1 || len > 256) {
|
||||
l_error("anti-clogging token size invalid %zu", len);
|
||||
return;
|
||||
return -EBADMSG;
|
||||
}
|
||||
|
||||
sm->token = l_memdup(ptr + 2, len - 2);
|
||||
sm->token_len = len - 2;
|
||||
sm->token = l_memdup(ptr, len);
|
||||
sm->token_len = len;
|
||||
sm->sync = 0;
|
||||
|
||||
sae_send_commit(sm, true);
|
||||
|
||||
return -EAGAIN;
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -736,25 +910,6 @@ static int sae_verify_nothing(struct sae_sm *sm, uint16_t transaction,
|
|||
return 0;
|
||||
}
|
||||
|
||||
static void sae_reset_state(struct sae_sm *sm)
|
||||
{
|
||||
l_free(sm->token);
|
||||
sm->token = NULL;
|
||||
|
||||
l_ecc_scalar_free(sm->scalar);
|
||||
sm->scalar = NULL;
|
||||
l_ecc_scalar_free(sm->p_scalar);
|
||||
sm->p_scalar = NULL;
|
||||
l_ecc_scalar_free(sm->rand);
|
||||
sm->rand = NULL;
|
||||
l_ecc_point_free(sm->element);
|
||||
sm->element = NULL;
|
||||
l_ecc_point_free(sm->p_element);
|
||||
sm->p_element = NULL;
|
||||
l_ecc_point_free(sm->pwe);
|
||||
sm->pwe = NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* 802.11-2016 - 12.4.8.6.4 Protocol instance behavior - Committed state
|
||||
*/
|
||||
|
|
@ -762,6 +917,9 @@ static int sae_verify_committed(struct sae_sm *sm, uint16_t transaction,
|
|||
uint16_t status, const uint8_t *frame,
|
||||
size_t len)
|
||||
{
|
||||
unsigned int skip;
|
||||
struct ie_tlv_iter iter;
|
||||
|
||||
/*
|
||||
* Upon receipt of a Con event...
|
||||
* Then the protocol instance checks the value of Sync. If it
|
||||
|
|
@ -781,11 +939,10 @@ static int sae_verify_committed(struct sae_sm *sm, uint16_t transaction,
|
|||
return -EAGAIN;
|
||||
}
|
||||
|
||||
switch (status) {
|
||||
case MMPDU_STATUS_CODE_ANTI_CLOGGING_TOKEN_REQ:
|
||||
sae_process_anti_clogging(sm, frame, len);
|
||||
return -EAGAIN;
|
||||
case MMPDU_STATUS_CODE_UNSUPP_FINITE_CYCLIC_GROUP:
|
||||
if (status == MMPDU_STATUS_CODE_ANTI_CLOGGING_TOKEN_REQ)
|
||||
return sae_process_anti_clogging(sm, frame, len);
|
||||
|
||||
if (status == MMPDU_STATUS_CODE_UNSUPP_FINITE_CYCLIC_GROUP) {
|
||||
/*
|
||||
* TODO: hostapd in its current state does not include the
|
||||
* group number as it should. This is a violation of the spec,
|
||||
|
|
@ -808,17 +965,7 @@ static int sae_verify_committed(struct sae_sm *sm, uint16_t transaction,
|
|||
else if (len >= 2 && (l_get_le16(frame) != sm->group))
|
||||
return -ENOMSG;
|
||||
|
||||
sm->group_retry++;
|
||||
|
||||
if (sm->ecc_groups[sm->group_retry] == 0) {
|
||||
/*
|
||||
* "If there are no other groups to choose, the protocol
|
||||
* instance shall send a Del event to the parent process
|
||||
* and transitions back to Nothing state"
|
||||
*/
|
||||
sm->state = SAE_STATE_NOTHING;
|
||||
goto reject_unsupp_group;
|
||||
}
|
||||
sae_rejected_groups_append(sm, L_CPU_TO_LE16(sm->group));
|
||||
|
||||
/*
|
||||
* "If the rejected group matches the last offered group, the
|
||||
|
|
@ -828,40 +975,85 @@ static int sae_verify_committed(struct sae_sm *sm, uint16_t transaction,
|
|||
* zeros Sync, sets the t0 (retransmission) timer, and remains
|
||||
* in Committed state"
|
||||
*/
|
||||
|
||||
sae_reset_state(sm);
|
||||
|
||||
sm->group = sm->ecc_groups[sm->group_retry];
|
||||
sm->curve = l_ecc_curve_from_ike_group(sm->group);
|
||||
if (sae_choose_next_group(sm) < 0) {
|
||||
/*
|
||||
* "If there are no other groups to choose, the protocol
|
||||
* instance shall send a Del event to the parent process
|
||||
* and transitions back to Nothing state"
|
||||
*/
|
||||
sm->state = SAE_STATE_NOTHING;
|
||||
goto reject_unsupp_group;
|
||||
}
|
||||
|
||||
sm->sync = 0;
|
||||
sae_send_commit(sm, false);
|
||||
|
||||
return -EAGAIN;
|
||||
case 0:
|
||||
if (len < 2)
|
||||
return -EBADMSG;
|
||||
|
||||
if (l_get_le16(frame) != sm->group) {
|
||||
l_error("SAE: Peer tried to change group -- Reject");
|
||||
goto reject_unsupp_group;
|
||||
}
|
||||
|
||||
len -= 2;
|
||||
|
||||
if (len < l_ecc_curve_get_scalar_bytes(sm->curve) * 3)
|
||||
return -EBADMSG;
|
||||
|
||||
return 0;
|
||||
default:
|
||||
/*
|
||||
* If the Status is some other nonzero value, the frame shall
|
||||
* be silently discarded and the t0 (retransmission) timer
|
||||
* shall be set.
|
||||
*/
|
||||
return -ENOMSG;
|
||||
}
|
||||
|
||||
/*
|
||||
* If the Status is some other nonzero value, the frame shall be
|
||||
* silently discarded and the t0 (retransmission) timer shall be set.
|
||||
*/
|
||||
if (status != 0 && status != MMPDU_STATUS_CODE_SAE_HASH_TO_ELEMENT)
|
||||
return -ENOMSG;
|
||||
|
||||
if (status != sae_status_code(sm))
|
||||
return -EBADMSG;
|
||||
|
||||
if (len < 2)
|
||||
return -EBADMSG;
|
||||
|
||||
if (l_get_le16(frame) != sm->group) {
|
||||
l_error("SAE: Peer tried to change group -- Reject");
|
||||
goto reject_unsupp_group;
|
||||
}
|
||||
|
||||
len -= 2;
|
||||
frame += 2;
|
||||
|
||||
skip = l_ecc_curve_get_scalar_bytes(sm->curve) * 3;
|
||||
if (len < skip)
|
||||
return -EBADMSG;
|
||||
|
||||
/* If H2E isn't being used, there should be no IEs in use */
|
||||
if (status == 0)
|
||||
return 0;
|
||||
|
||||
len -= skip;
|
||||
frame += skip;
|
||||
|
||||
ie_tlv_iter_init(&iter, frame, len);
|
||||
|
||||
while (ie_tlv_iter_next(&iter)) {
|
||||
switch (ie_tlv_iter_get_tag(&iter)) {
|
||||
/*
|
||||
* If the peer's SAE Commit message contains a Rejected Groups
|
||||
* element, the list of rejected groups shall be checked to
|
||||
* ensure that all of the groups in the list are groups that
|
||||
* would be rejected. If any groups in the list would not be
|
||||
* rejected then processing of the SAE Commit message
|
||||
* terminates and the STA shall reject the peer's
|
||||
* authentication.
|
||||
*
|
||||
* NOTE: We currently only support the Initiator role, and so
|
||||
* do not reject any groups. We should never receive this
|
||||
* element
|
||||
*/
|
||||
case IE_TYPE_REJECTED_GROUPS:
|
||||
l_error("SAE: Unexpected Rejected Groups IE");
|
||||
return sae_reject(sm, SAE_STATE_COMMITTED,
|
||||
MMPDU_STATUS_CODE_UNSPECIFIED);
|
||||
/* We don't request tokens, so we shouldn't get any */
|
||||
case IE_TYPE_ANTI_CLOGGING_TOKEN_CONTAINER:
|
||||
l_error("SAE: Unexpected Anti-Clogging Container IE");
|
||||
return sae_reject(sm, SAE_STATE_COMMITTED,
|
||||
MMPDU_STATUS_CODE_UNSPECIFIED);
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
reject_unsupp_group:
|
||||
return sae_reject(sm, SAE_STATE_COMMITTED,
|
||||
MMPDU_STATUS_CODE_UNSUPP_FINITE_CYCLIC_GROUP);
|
||||
|
|
@ -874,8 +1066,26 @@ static int sae_verify_confirmed(struct sae_sm *sm, uint16_t trans,
|
|||
uint16_t status, const uint8_t *frame,
|
||||
size_t len)
|
||||
{
|
||||
if (trans == SAE_STATE_CONFIRMED)
|
||||
if (trans == SAE_STATE_CONFIRMED) {
|
||||
enum l_checksum_type hash =
|
||||
crypto_sae_hash_from_ecc_prime_len(sm->sae_type,
|
||||
l_ecc_curve_get_scalar_bytes(sm->curve));
|
||||
size_t hash_len = l_checksum_digest_length(hash);
|
||||
|
||||
/* Most likely the password is wrong */
|
||||
if (status == MMPDU_STATUS_CODE_UNSPECIFIED && len == 0)
|
||||
return -ENOKEY;
|
||||
|
||||
if (status != MMPDU_STATUS_CODE_SUCCESS)
|
||||
return -EPROTO;
|
||||
|
||||
if (len < hash_len + 2) {
|
||||
l_error("SAE: Confirm packet too short");
|
||||
return -EBADMSG;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Upon receipt of a Com event, the t0 (retransmission) timer shall be
|
||||
|
|
@ -909,7 +1119,9 @@ static int sae_verify_confirmed(struct sae_sm *sm, uint16_t trans,
|
|||
sm->sc++;
|
||||
|
||||
sae_send_commit(sm, true);
|
||||
sae_send_confirm(sm);
|
||||
|
||||
if (!sae_send_confirm(sm))
|
||||
return -EPROTO;
|
||||
|
||||
return -EAGAIN;
|
||||
}
|
||||
|
|
@ -961,7 +1173,8 @@ static int sae_verify_accepted(struct sae_sm *sm, uint16_t trans,
|
|||
sm->sync++;
|
||||
sm->sc = 0xffff;
|
||||
|
||||
sae_send_confirm(sm);
|
||||
if (!sae_send_confirm(sm))
|
||||
return -EPROTO;
|
||||
|
||||
return -EAGAIN;
|
||||
}
|
||||
|
|
@ -1055,6 +1268,14 @@ static bool sae_start(struct auth_proto *ap)
|
|||
else
|
||||
memcpy(sm->peer, sm->handshake->aa, 6);
|
||||
|
||||
if (sm->sae_type == CRYPTO_SAE_LOOPING && !sm->handshake->passphrase) {
|
||||
l_error("SAE: No passphrase set");
|
||||
return false;
|
||||
}
|
||||
|
||||
if (sae_choose_next_group(sm) < 0)
|
||||
return false;
|
||||
|
||||
sm->state = SAE_STATE_COMMITTED;
|
||||
return sae_send_commit(sm, false);
|
||||
}
|
||||
|
|
@ -1065,6 +1286,9 @@ static void sae_free(struct auth_proto *ap)
|
|||
|
||||
sae_reset_state(sm);
|
||||
|
||||
if (sm->rejected_groups)
|
||||
free(sm->rejected_groups);
|
||||
|
||||
/* zero out whole structure, including keys */
|
||||
explicit_bzero(sm, sizeof(struct sae_sm));
|
||||
|
||||
|
|
@ -1077,20 +1301,17 @@ struct auth_proto *sae_sm_new(struct handshake_state *hs,
|
|||
void *user_data)
|
||||
{
|
||||
struct sae_sm *sm;
|
||||
const void *rsnxe;
|
||||
|
||||
sm = l_new(struct sae_sm, 1);
|
||||
|
||||
if (!sm)
|
||||
return NULL;
|
||||
sm->group_retry = -1;
|
||||
|
||||
sm->tx_auth = tx_auth;
|
||||
sm->tx_assoc = tx_assoc;
|
||||
sm->user_data = user_data;
|
||||
sm->handshake = hs;
|
||||
sm->state = SAE_STATE_NOTHING;
|
||||
sm->ecc_groups = l_ecc_supported_ike_groups();
|
||||
sm->group = sm->ecc_groups[sm->group_retry];
|
||||
sm->curve = l_ecc_curve_from_ike_group(sm->group);
|
||||
|
||||
sm->ap.start = sae_start;
|
||||
sm->ap.free = sae_free;
|
||||
|
|
@ -1098,5 +1319,16 @@ struct auth_proto *sae_sm_new(struct handshake_state *hs,
|
|||
sm->ap.rx_associate = sae_rx_associate;
|
||||
sm->ap.assoc_timeout = sae_assoc_timeout;
|
||||
|
||||
rsnxe = hs->authenticator ? hs->supplicant_rsnxe :
|
||||
hs->authenticator_rsnxe;
|
||||
|
||||
if (ie_rsnxe_capable(rsnxe, IE_RSNX_SAE_H2E) && hs->ecc_sae_pts) {
|
||||
l_debug("Using SAE H2E");
|
||||
sm->sae_type = CRYPTO_SAE_HASH_TO_ELEMENT;
|
||||
} else {
|
||||
l_debug("Using SAE Hunting and Pecking");
|
||||
sm->sae_type = CRYPTO_SAE_LOOPING;
|
||||
}
|
||||
|
||||
return &sm->ap;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue