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-rw-r--r--src/eap_peer/eap_pwd.c730
1 files changed, 730 insertions, 0 deletions
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
new file mode 100644
index 0000000..8d21b92
--- /dev/null
+++ b/src/eap_peer/eap_pwd.c
@@ -0,0 +1,730 @@
+/*
+ * EAP peer method: EAP-pwd (RFC 5931)
+ * Copyright (c) 2010, Dan Harkins <dharkins@lounge.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the BSD license.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "eap_peer/eap_i.h"
+#include "eap_common/eap_pwd_common.h"
+
+
+struct eap_pwd_data {
+ enum {
+ PWD_ID_Req, PWD_Commit_Req, PWD_Confirm_Req, SUCCESS, FAILURE
+ } state;
+ u8 *id_peer;
+ size_t id_peer_len;
+ u8 *id_server;
+ size_t id_server_len;
+ u8 *password;
+ size_t password_len;
+ u16 group_num;
+ EAP_PWD_group *grp;
+
+ BIGNUM *k;
+ BIGNUM *private_value;
+ BIGNUM *server_scalar;
+ BIGNUM *my_scalar;
+ EC_POINT *my_element;
+ EC_POINT *server_element;
+
+ u8 msk[EAP_MSK_LEN];
+ u8 emsk[EAP_EMSK_LEN];
+};
+
+static BN_CTX *bnctx;
+
+
+#ifndef CONFIG_NO_STDOUT_DEBUG
+static const char * eap_pwd_state_txt(int state)
+{
+ switch (state) {
+ case PWD_ID_Req:
+ return "PWD-ID-Req";
+ case PWD_Commit_Req:
+ return "PWD-Commit-Req";
+ case PWD_Confirm_Req:
+ return "PWD-Confirm-Req";
+ case SUCCESS:
+ return "SUCCESS";
+ case FAILURE:
+ return "FAILURE";
+ default:
+ return "PWD-UNK";
+ }
+}
+#endif /* CONFIG_NO_STDOUT_DEBUG */
+
+
+static void eap_pwd_state(struct eap_pwd_data *data, int state)
+{
+ wpa_printf(MSG_INFO, "EAP-PWD: %s -> %s",
+ eap_pwd_state_txt(data->state), eap_pwd_state_txt(state));
+ data->state = state;
+}
+
+
+static void * eap_pwd_init(struct eap_sm *sm)
+{
+ struct eap_pwd_data *data;
+ const u8 *identity, *password;
+ size_t identity_len, password_len;
+
+ password = eap_get_config_password(sm, &password_len);
+ if (password == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: No password configured!");
+ return NULL;
+ }
+
+ identity = eap_get_config_identity(sm, &identity_len);
+ if (identity == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: No identity configured!");
+ return NULL;
+ }
+
+ if ((bnctx = BN_CTX_new()) == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: bn context allocation fail");
+ return NULL;
+ }
+
+ if ((data = os_zalloc(sizeof(*data))) == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: memory allocation data fail");
+ return NULL;
+ }
+
+ if ((data->id_peer = os_malloc(identity_len)) == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
+ os_free(data);
+ return NULL;
+ }
+
+ os_memcpy(data->id_peer, identity, identity_len);
+ data->id_peer_len = identity_len;
+
+ if ((data->password = os_malloc(password_len)) == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: memory allocation psk fail");
+ os_free(data->id_peer);
+ os_free(data);
+ return NULL;
+ }
+ os_memcpy(data->password, password, password_len);
+ data->password_len = password_len;
+
+ data->state = PWD_ID_Req;
+
+ return data;
+}
+
+
+static void eap_pwd_deinit(struct eap_sm *sm, void *priv)
+{
+ struct eap_pwd_data *data = priv;
+
+ BN_free(data->private_value);
+ BN_free(data->server_scalar);
+ BN_free(data->my_scalar);
+ BN_free(data->k);
+ BN_CTX_free(bnctx);
+ EC_POINT_free(data->my_element);
+ EC_POINT_free(data->server_element);
+ os_free(data->id_peer);
+ os_free(data->password);
+ os_free(data->grp);
+ os_free(data);
+}
+
+
+static u8 * eap_pwd_getkey(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_pwd_data *data = priv;
+ u8 *key;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ key = os_malloc(EAP_MSK_LEN);
+ if (key == NULL)
+ return NULL;
+
+ os_memcpy(key, data->msk, EAP_MSK_LEN);
+ *len = EAP_MSK_LEN;
+
+ return key;
+}
+
+
+static struct wpabuf *
+eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
+ struct eap_method_ret *ret,
+ const struct wpabuf *reqData,
+ const u8 *payload, size_t payload_len)
+{
+ struct eap_pwd_id *id;
+ struct wpabuf *resp;
+
+ if (data->state != PWD_ID_Req) {
+ ret->ignore = TRUE;
+ return NULL;
+ }
+
+ if (payload_len < sizeof(struct eap_pwd_id)) {
+ ret->ignore = TRUE;
+ return NULL;
+ }
+
+ id = (struct eap_pwd_id *) payload;
+ data->group_num = be_to_host16(id->group_num);
+ if ((id->random_function != EAP_PWD_DEFAULT_RAND_FUNC) ||
+ (id->prf != EAP_PWD_DEFAULT_PRF)) {
+ ret->ignore = TRUE;
+ return NULL;
+ }
+
+ wpa_printf(MSG_DEBUG, "EAP-PWD (peer): server said group %d",
+ data->group_num);
+
+ data->id_server = os_malloc(payload_len - sizeof(struct eap_pwd_id));
+ if (data->id_server == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
+ return NULL;
+ }
+ data->id_server_len = payload_len - sizeof(struct eap_pwd_id);
+ os_memcpy(data->id_server, id->identity, data->id_server_len);
+ wpa_hexdump_ascii(MSG_INFO, "EAP-PWD (peer): server sent id of",
+ data->id_server, data->id_server_len);
+
+ if ((data->grp = (EAP_PWD_group *) os_malloc(sizeof(EAP_PWD_group))) ==
+ NULL) {
+ wpa_printf(MSG_INFO, "EAP-PWD: failed to allocate memory for "
+ "group");
+ return NULL;
+ }
+
+ /* compute PWE */
+ if (compute_password_element(data->grp, data->group_num,
+ data->password, data->password_len,
+ data->id_server, data->id_server_len,
+ data->id_peer, data->id_peer_len,
+ id->token)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute PWE");
+ return NULL;
+ }
+
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): computed %d bit PWE...",
+ BN_num_bits(data->grp->prime));
+
+ resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+ 1 + sizeof(struct eap_pwd_id) + data->id_peer_len,
+ EAP_CODE_RESPONSE, eap_get_id(reqData));
+ if (resp == NULL)
+ return NULL;
+
+ wpabuf_put_u8(resp, EAP_PWD_OPCODE_ID_EXCH);
+ wpabuf_put_be16(resp, data->group_num);
+ wpabuf_put_u8(resp, EAP_PWD_DEFAULT_RAND_FUNC);
+ wpabuf_put_u8(resp, EAP_PWD_DEFAULT_PRF);
+ wpabuf_put_data(resp, id->token, sizeof(id->token));
+ wpabuf_put_u8(resp, EAP_PWD_PREP_NONE);
+ wpabuf_put_data(resp, data->id_peer, data->id_peer_len);
+
+ eap_pwd_state(data, PWD_Commit_Req);
+
+ return resp;
+}
+
+
+static struct wpabuf *
+eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
+ struct eap_method_ret *ret,
+ const struct wpabuf *reqData,
+ const u8 *payload, size_t payload_len)
+{
+ struct wpabuf *resp = NULL;
+ EC_POINT *K = NULL, *point = NULL;
+ BIGNUM *mask = NULL, *x = NULL, *y = NULL, *cofactor = NULL;
+ u16 offset;
+ u8 *ptr, *scalar = NULL, *element = NULL;
+
+ if (((data->private_value = BN_new()) == NULL) ||
+ ((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
+ ((cofactor = BN_new()) == NULL) ||
+ ((data->my_scalar = BN_new()) == NULL) ||
+ ((mask = BN_new()) == NULL)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): scalar allocation fail");
+ goto fin;
+ }
+
+ if (!EC_GROUP_get_cofactor(data->grp->group, cofactor, NULL)) {
+ wpa_printf(MSG_INFO, "EAP-pwd (peer): unable to get cofactor "
+ "for curve");
+ goto fin;
+ }
+
+ BN_rand_range(data->private_value, data->grp->order);
+ BN_rand_range(mask, data->grp->order);
+ BN_add(data->my_scalar, data->private_value, mask);
+ BN_mod(data->my_scalar, data->my_scalar, data->grp->order, bnctx);
+
+ if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
+ data->grp->pwe, mask, bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): element allocation "
+ "fail");
+ eap_pwd_state(data, FAILURE);
+ goto fin;
+ }
+
+ if (!EC_POINT_invert(data->grp->group, data->my_element, bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): element inversion fail");
+ goto fin;
+ }
+ BN_free(mask);
+
+ if (((x = BN_new()) == NULL) ||
+ ((y = BN_new()) == NULL)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): point allocation fail");
+ goto fin;
+ }
+
+ /* process the request */
+ if (((data->server_scalar = BN_new()) == NULL) ||
+ ((data->k = BN_new()) == NULL) ||
+ ((K = EC_POINT_new(data->grp->group)) == NULL) ||
+ ((point = EC_POINT_new(data->grp->group)) == NULL) ||
+ ((data->server_element = EC_POINT_new(data->grp->group)) == NULL))
+ {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): peer data allocation "
+ "fail");
+ goto fin;
+ }
+
+ /* element, x then y, followed by scalar */
+ ptr = (u8 *) payload;
+ BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), x);
+ ptr += BN_num_bytes(data->grp->prime);
+ BN_bin2bn(ptr, BN_num_bytes(data->grp->prime), y);
+ ptr += BN_num_bytes(data->grp->prime);
+ BN_bin2bn(ptr, BN_num_bytes(data->grp->order), data->server_scalar);
+ if (!EC_POINT_set_affine_coordinates_GFp(data->grp->group,
+ data->server_element, x, y,
+ bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): setting peer element "
+ "fail");
+ goto fin;
+ }
+
+ /* check to ensure server's element is not in a small sub-group */
+ if (BN_cmp(cofactor, BN_value_one())) {
+ if (!EC_POINT_mul(data->grp->group, point, NULL,
+ data->server_element, cofactor, NULL)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
+ "server element by order!\n");
+ goto fin;
+ }
+ if (EC_POINT_is_at_infinity(data->grp->group, point)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): server element "
+ "is at infinity!\n");
+ goto fin;
+ }
+ }
+
+ /* compute the shared key, k */
+ if ((!EC_POINT_mul(data->grp->group, K, NULL, data->grp->pwe,
+ data->server_scalar, bnctx)) ||
+ (!EC_POINT_add(data->grp->group, K, K, data->server_element,
+ bnctx)) ||
+ (!EC_POINT_mul(data->grp->group, K, NULL, K, data->private_value,
+ bnctx))) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): computing shared key "
+ "fail");
+ goto fin;
+ }
+
+ /* ensure that the shared key isn't in a small sub-group */
+ if (BN_cmp(cofactor, BN_value_one())) {
+ if (!EC_POINT_mul(data->grp->group, K, NULL, K, cofactor,
+ NULL)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
+ "shared key point by order");
+ goto fin;
+ }
+ }
+
+ /*
+ * This check is strictly speaking just for the case above where
+ * co-factor > 1 but it was suggested that even though this is probably
+ * never going to happen it is a simple and safe check "just to be
+ * sure" so let's be safe.
+ */
+ if (EC_POINT_is_at_infinity(data->grp->group, K)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): shared key point is at "
+ "infinity!\n");
+ goto fin;
+ }
+
+ if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group, K, data->k,
+ NULL, bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to extract "
+ "shared secret from point");
+ goto fin;
+ }
+
+ /* now do the response */
+ if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+ data->my_element, x, y,
+ bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): point assignment fail");
+ goto fin;
+ }
+
+ if (((scalar = os_malloc(BN_num_bytes(data->grp->order))) == NULL) ||
+ ((element = os_malloc(BN_num_bytes(data->grp->prime) * 2)) ==
+ NULL)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): data allocation fail");
+ goto fin;
+ }
+
+ /*
+ * bignums occupy as little memory as possible so one that is
+ * sufficiently smaller than the prime or order might need pre-pending
+ * with zeros.
+ */
+ os_memset(scalar, 0, BN_num_bytes(data->grp->order));
+ os_memset(element, 0, BN_num_bytes(data->grp->prime) * 2);
+ offset = BN_num_bytes(data->grp->order) -
+ BN_num_bytes(data->my_scalar);
+ BN_bn2bin(data->my_scalar, scalar + offset);
+
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+ BN_bn2bin(x, element + offset);
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+ BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);
+
+ resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+ sizeof(struct eap_pwd_hdr) +
+ BN_num_bytes(data->grp->order) +
+ (2 * BN_num_bytes(data->grp->prime)),
+ EAP_CODE_RESPONSE, eap_get_id(reqData));
+ if (resp == NULL)
+ goto fin;
+
+ wpabuf_put_u8(resp, EAP_PWD_OPCODE_COMMIT_EXCH);
+
+ /* we send the element as (x,y) follwed by the scalar */
+ wpabuf_put_data(resp, element, (2 * BN_num_bytes(data->grp->prime)));
+ wpabuf_put_data(resp, scalar, BN_num_bytes(data->grp->order));
+
+fin:
+ os_free(scalar);
+ os_free(element);
+ BN_free(x);
+ BN_free(y);
+ BN_free(cofactor);
+ EC_POINT_free(K);
+ EC_POINT_free(point);
+ if (resp == NULL)
+ eap_pwd_state(data, FAILURE);
+ else
+ eap_pwd_state(data, PWD_Confirm_Req);
+
+ return resp;
+}
+
+
+static struct wpabuf *
+eap_pwd_perform_confirm_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
+ struct eap_method_ret *ret,
+ const struct wpabuf *reqData,
+ const u8 *payload, size_t payload_len)
+{
+ struct wpabuf *resp = NULL;
+ BIGNUM *x = NULL, *y = NULL;
+ HMAC_CTX ctx;
+ u32 cs;
+ u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
+
+ /*
+ * first build up the ciphersuite which is group | random_function |
+ * prf
+ */
+ ptr = (u8 *) &cs;
+ os_memcpy(ptr, &data->group_num, sizeof(u16));
+ ptr += sizeof(u16);
+ *ptr = EAP_PWD_DEFAULT_RAND_FUNC;
+ ptr += sizeof(u8);
+ *ptr = EAP_PWD_DEFAULT_PRF;
+
+ /* each component of the cruft will be at most as big as the prime */
+ if (((cruft = os_malloc(BN_num_bytes(data->grp->prime))) == NULL) ||
+ ((x = BN_new()) == NULL) || ((y = BN_new()) == NULL)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (server): debug allocation "
+ "fail");
+ goto fin;
+ }
+
+ /*
+ * server's commit is H(k | server_element | server_scalar |
+ * peer_element | peer_scalar | ciphersuite)
+ */
+ H_Init(&ctx);
+
+ /*
+ * zero the memory each time because this is mod prime math and some
+ * value may start with a few zeros and the previous one did not.
+ */
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(data->k, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+ /* server element: x, y */
+ if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+ data->server_element, x, y,
+ bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+ "assignment fail");
+ goto fin;
+ }
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(x, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(y, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+ /* server scalar */
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(data->server_scalar, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+ /* my element: x, y */
+ if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+ data->my_element, x, y,
+ bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
+ "assignment fail");
+ goto fin;
+ }
+
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(x, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(y, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+ /* my scalar */
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(data->my_scalar, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+ /* the ciphersuite */
+ H_Update(&ctx, (u8 *) &cs, sizeof(u32));
+
+ /* random function fin */
+ H_Final(&ctx, conf);
+
+ ptr = (u8 *) payload;
+ if (os_memcmp(conf, ptr, SHA256_DIGEST_LENGTH)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm did not verify");
+ goto fin;
+ }
+
+ wpa_printf(MSG_DEBUG, "EAP-pwd (peer): confirm verified");
+
+ /*
+ * compute confirm:
+ * H(k | peer_element | peer_scalar | server_element | server_scalar |
+ * ciphersuite)
+ */
+ H_Init(&ctx);
+
+ /* k */
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(data->k, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+ /* my element */
+ if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+ data->my_element, x, y,
+ bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
+ "assignment fail");
+ goto fin;
+ }
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(x, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(y, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+ /* my scalar */
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(data->my_scalar, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+ /* server element: x, y */
+ if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
+ data->server_element, x, y,
+ bnctx)) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
+ "assignment fail");
+ goto fin;
+ }
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(x, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(y, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+
+ /* server scalar */
+ os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
+ BN_bn2bin(data->server_scalar, cruft);
+ H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+
+ /* the ciphersuite */
+ H_Update(&ctx, (u8 *) &cs, sizeof(u32));
+
+ /* all done */
+ H_Final(&ctx, conf);
+
+ resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+ sizeof(struct eap_pwd_hdr) + SHA256_DIGEST_LENGTH,
+ EAP_CODE_RESPONSE, eap_get_id(reqData));
+ if (resp == NULL)
+ goto fin;
+
+ wpabuf_put_u8(resp, EAP_PWD_OPCODE_CONFIRM_EXCH);
+ wpabuf_put_data(resp, conf, SHA256_DIGEST_LENGTH);
+
+ if (compute_keys(data->grp, bnctx, data->k, data->server_element,
+ data->my_element, data->server_scalar,
+ data->my_scalar, &cs, data->msk, data->emsk) < 0) {
+ wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute MSK | "
+ "EMSK");
+ goto fin;
+ }
+
+fin:
+ os_free(cruft);
+ BN_free(x);
+ BN_free(y);
+ ret->methodState = METHOD_DONE;
+ if (resp == NULL) {
+ ret->decision = DECISION_FAIL;
+ eap_pwd_state(data, FAILURE);
+ } else {
+ ret->decision = DECISION_UNCOND_SUCC;
+ eap_pwd_state(data, SUCCESS);
+ }
+
+ return resp;
+}
+
+
+static struct wpabuf *
+eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
+ const struct wpabuf *reqData)
+{
+ struct eap_pwd_data *data = priv;
+ struct wpabuf *resp = NULL;
+ const u8 *pos;
+ size_t len;
+ u8 exch;
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, reqData, &len);
+ if ((pos == NULL) || (len < 1)) {
+ ret->ignore = TRUE;
+ return NULL;
+ }
+
+ wpa_printf(MSG_INFO, "EAP-pwd: Received frame: opcode %d", *pos);
+
+ ret->ignore = FALSE;
+ ret->methodState = METHOD_MAY_CONT;
+ ret->decision = DECISION_FAIL;
+ ret->allowNotifications = FALSE;
+
+ exch = *pos & 0x3f;
+ switch (exch) {
+ case EAP_PWD_OPCODE_ID_EXCH:
+ resp = eap_pwd_perform_id_exchange(sm, data, ret, reqData,
+ pos + 1, len - 1);
+ break;
+ case EAP_PWD_OPCODE_COMMIT_EXCH:
+ resp = eap_pwd_perform_commit_exchange(sm, data, ret, reqData,
+ pos + 1, len - 1);
+ break;
+ case EAP_PWD_OPCODE_CONFIRM_EXCH:
+ resp = eap_pwd_perform_confirm_exchange(sm, data, ret, reqData,
+ pos + 1, len - 1);
+ break;
+ default:
+ wpa_printf(MSG_INFO, "EAP-pwd: Ignoring message with unknown "
+ "opcode %d", exch);
+ break;
+ }
+
+ return resp;
+}
+
+
+static Boolean eap_pwd_key_available(struct eap_sm *sm, void *priv)
+{
+ struct eap_pwd_data *data = priv;
+ return data->state == SUCCESS;
+}
+
+
+static u8 * eap_pwd_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_pwd_data *data = priv;
+ u8 *key;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ if ((key = os_malloc(EAP_EMSK_LEN)) == NULL)
+ return NULL;
+
+ os_memcpy(key, data->emsk, EAP_EMSK_LEN);
+ *len = EAP_EMSK_LEN;
+
+ return key;
+}
+
+
+int eap_peer_pwd_register(void)
+{
+ struct eap_method *eap;
+ int ret;
+
+ EVP_add_digest(EVP_sha256());
+ eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
+ EAP_VENDOR_IETF, EAP_TYPE_PWD, "PWD");
+ if (eap == NULL)
+ return -1;
+
+ eap->init = eap_pwd_init;
+ eap->deinit = eap_pwd_deinit;
+ eap->process = eap_pwd_process;
+ eap->isKeyAvailable = eap_pwd_key_available;
+ eap->getKey = eap_pwd_getkey;
+ eap->get_emsk = eap_pwd_get_emsk;
+
+ ret = eap_peer_method_register(eap);
+ if (ret)
+ eap_peer_method_free(eap);
+ return ret;
+}