* hostapd / EAP-pwd (RFC 5931) server
* 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.
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
*/
#include "includes.h"
#include "common.h"
+#include "crypto/sha256.h"
+#include "crypto/ms_funcs.h"
#include "eap_server/eap_i.h"
#include "eap_common/eap_pwd_common.h"
size_t id_server_len;
u8 *password;
size_t password_len;
+ int password_hash;
u32 token;
u16 group_num;
EAP_PWD_group *grp;
+ struct wpabuf *inbuf;
+ size_t in_frag_pos;
+ struct wpabuf *outbuf;
+ size_t out_frag_pos;
+ size_t mtu;
+
BIGNUM *k;
BIGNUM *private_value;
BIGNUM *peer_scalar;
EC_POINT *my_element;
EC_POINT *peer_element;
+ u8 my_confirm[SHA256_MAC_LEN];
+
u8 msk[EAP_MSK_LEN];
u8 emsk[EAP_EMSK_LEN];
+ u8 session_id[1 + SHA256_MAC_LEN];
BN_CTX *bnctx;
};
if (data->password == NULL) {
wpa_printf(MSG_INFO, "EAP-PWD: Memory allocation password "
"fail");
- os_free(data->id_server);
+ bin_clear_free(data->id_server, data->id_server_len);
os_free(data);
return NULL;
}
data->password_len = sm->user->password_len;
os_memcpy(data->password, sm->user->password, data->password_len);
+ data->password_hash = sm->user->password_hash;
data->bnctx = BN_CTX_new();
if (data->bnctx == NULL) {
wpa_printf(MSG_INFO, "EAP-PWD: bn context allocation fail");
- os_free(data->password);
- os_free(data->id_server);
+ bin_clear_free(data->password, data->password_len);
+ bin_clear_free(data->id_server, data->id_server_len);
os_free(data);
return NULL;
}
+ data->in_frag_pos = data->out_frag_pos = 0;
+ data->inbuf = data->outbuf = NULL;
+ /* use default MTU from RFC 5931 if not configured otherwise */
+ data->mtu = sm->fragment_size > 0 ? sm->fragment_size : 1020;
+
return data;
}
{
struct eap_pwd_data *data = priv;
- BN_free(data->private_value);
- BN_free(data->peer_scalar);
- BN_free(data->my_scalar);
- BN_free(data->k);
+ BN_clear_free(data->private_value);
+ BN_clear_free(data->peer_scalar);
+ BN_clear_free(data->my_scalar);
+ BN_clear_free(data->k);
BN_CTX_free(data->bnctx);
- EC_POINT_free(data->my_element);
- EC_POINT_free(data->peer_element);
- os_free(data->id_peer);
- os_free(data->id_server);
- os_free(data->password);
+ EC_POINT_clear_free(data->my_element);
+ EC_POINT_clear_free(data->peer_element);
+ bin_clear_free(data->id_peer, data->id_peer_len);
+ bin_clear_free(data->id_server, data->id_server_len);
+ bin_clear_free(data->password, data->password_len);
if (data->grp) {
EC_GROUP_free(data->grp->group);
- EC_POINT_free(data->grp->pwe);
- BN_free(data->grp->order);
- BN_free(data->grp->prime);
+ EC_POINT_clear_free(data->grp->pwe);
+ BN_clear_free(data->grp->order);
+ BN_clear_free(data->grp->prime);
os_free(data->grp);
}
- os_free(data);
+ wpabuf_free(data->inbuf);
+ wpabuf_free(data->outbuf);
+ bin_clear_free(data, sizeof(*data));
}
-static struct wpabuf *
-eap_pwd_build_id_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
+static void eap_pwd_build_id_req(struct eap_sm *sm, struct eap_pwd_data *data,
+ u8 id)
{
- struct wpabuf *req;
-
wpa_printf(MSG_DEBUG, "EAP-pwd: ID/Request");
- req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
- sizeof(struct eap_pwd_hdr) +
- sizeof(struct eap_pwd_id) + data->id_server_len,
- EAP_CODE_REQUEST, id);
- if (req == NULL) {
+ /*
+ * if we're fragmenting then we already have an id request, just return
+ */
+ if (data->out_frag_pos)
+ return;
+
+ data->outbuf = wpabuf_alloc(sizeof(struct eap_pwd_id) +
+ data->id_server_len);
+ if (data->outbuf == NULL) {
eap_pwd_state(data, FAILURE);
- return NULL;
+ return;
}
/* an lfsr is good enough to generate unpredictable tokens */
data->token = os_random();
- wpabuf_put_u8(req, EAP_PWD_OPCODE_ID_EXCH);
- wpabuf_put_be16(req, data->group_num);
- wpabuf_put_u8(req, EAP_PWD_DEFAULT_RAND_FUNC);
- wpabuf_put_u8(req, EAP_PWD_DEFAULT_PRF);
- wpabuf_put_data(req, &data->token, sizeof(data->token));
- wpabuf_put_u8(req, EAP_PWD_PREP_NONE);
- wpabuf_put_data(req, data->id_server, data->id_server_len);
-
- return req;
+ wpabuf_put_be16(data->outbuf, data->group_num);
+ wpabuf_put_u8(data->outbuf, EAP_PWD_DEFAULT_RAND_FUNC);
+ wpabuf_put_u8(data->outbuf, EAP_PWD_DEFAULT_PRF);
+ wpabuf_put_data(data->outbuf, &data->token, sizeof(data->token));
+ wpabuf_put_u8(data->outbuf, data->password_hash ? EAP_PWD_PREP_MS :
+ EAP_PWD_PREP_NONE);
+ wpabuf_put_data(data->outbuf, data->id_server, data->id_server_len);
}
-static struct wpabuf *
-eap_pwd_build_commit_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
+static void eap_pwd_build_commit_req(struct eap_sm *sm,
+ struct eap_pwd_data *data, u8 id)
{
- struct wpabuf *req = NULL;
BIGNUM *mask = NULL, *x = NULL, *y = NULL;
u8 *scalar = NULL, *element = NULL;
u16 offset;
wpa_printf(MSG_DEBUG, "EAP-pwd: Commit/Request");
+ /*
+ * if we're fragmenting then we already have an commit request, just
+ * return
+ */
+ if (data->out_frag_pos)
+ return;
if (((data->private_value = BN_new()) == NULL) ||
((data->my_element = EC_POINT_new(data->grp->group)) == NULL) ||
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,
- data->bnctx);
+ if (BN_rand_range(data->private_value, data->grp->order) != 1 ||
+ BN_rand_range(mask, data->grp->order) != 1 ||
+ BN_add(data->my_scalar, data->private_value, mask) != 1 ||
+ BN_mod(data->my_scalar, data->my_scalar, data->grp->order,
+ data->bnctx) != 1) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd (server): unable to get randomness");
+ goto fin;
+ }
if (!EC_POINT_mul(data->grp->group, data->my_element, NULL,
data->grp->pwe, mask, data->bnctx)) {
"fail");
goto fin;
}
- BN_free(mask);
+ BN_clear_free(mask);
if (((x = BN_new()) == NULL) ||
((y = BN_new()) == NULL)) {
offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
BN_bn2bin(y, element + BN_num_bytes(data->grp->prime) + offset);
- req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
- sizeof(struct eap_pwd_hdr) +
- (2 * BN_num_bytes(data->grp->prime)) +
- BN_num_bytes(data->grp->order),
- EAP_CODE_REQUEST, id);
- if (req == NULL)
+ data->outbuf = wpabuf_alloc(2 * BN_num_bytes(data->grp->prime) +
+ BN_num_bytes(data->grp->order));
+ if (data->outbuf == NULL)
goto fin;
- wpabuf_put_u8(req, EAP_PWD_OPCODE_COMMIT_EXCH);
/* We send the element as (x,y) followed by the scalar */
- wpabuf_put_data(req, element, (2 * BN_num_bytes(data->grp->prime)));
- wpabuf_put_data(req, scalar, BN_num_bytes(data->grp->order));
+ wpabuf_put_data(data->outbuf, element,
+ 2 * BN_num_bytes(data->grp->prime));
+ wpabuf_put_data(data->outbuf, scalar, BN_num_bytes(data->grp->order));
fin:
os_free(scalar);
os_free(element);
- BN_free(x);
- BN_free(y);
- if (req == NULL)
+ BN_clear_free(x);
+ BN_clear_free(y);
+ if (data->outbuf == NULL)
eap_pwd_state(data, FAILURE);
-
- return req;
}
-static struct wpabuf *
-eap_pwd_build_confirm_req(struct eap_sm *sm, struct eap_pwd_data *data, u8 id)
+static void eap_pwd_build_confirm_req(struct eap_sm *sm,
+ struct eap_pwd_data *data, u8 id)
{
- struct wpabuf *req = NULL;
BIGNUM *x = NULL, *y = NULL;
- HMAC_CTX ctx;
- u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
+ struct crypto_hash *hash;
+ u8 conf[SHA256_MAC_LEN], *cruft = NULL, *ptr;
+ u16 grp;
+ int offset;
wpa_printf(MSG_DEBUG, "EAP-pwd: Confirm/Request");
+ /*
+ * if we're fragmenting then we already have an confirm request, just
+ * return
+ */
+ if (data->out_frag_pos)
+ return;
/* 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) ||
* commit is H(k | server_element | server_scalar | peer_element |
* peer_scalar | ciphersuite)
*/
- H_Init(&ctx);
+ hash = eap_pwd_h_init();
+ if (hash == NULL)
+ goto fin;
/*
* Zero the memory each time because this is mod prime math and some
* First is 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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(data->k);
+ BN_bn2bin(data->k, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->prime));
/* server element: x, y */
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
}
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
- BN_bn2bin(x, cruft);
- H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+ BN_bn2bin(x, cruft + offset);
+ eap_pwd_h_update(hash, 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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+ BN_bn2bin(y, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->prime));
/* server 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));
+ offset = BN_num_bytes(data->grp->order) -
+ BN_num_bytes(data->my_scalar);
+ BN_bn2bin(data->my_scalar, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->order));
/* peer element: x, y */
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
}
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
- BN_bn2bin(x, cruft);
- H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+ BN_bn2bin(x, cruft + offset);
+ eap_pwd_h_update(hash, 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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+ BN_bn2bin(y, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->prime));
/* peer scalar */
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
- BN_bn2bin(data->peer_scalar, cruft);
- H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+ offset = BN_num_bytes(data->grp->order) -
+ BN_num_bytes(data->peer_scalar);
+ BN_bn2bin(data->peer_scalar, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->order));
/* ciphersuite */
+ grp = htons(data->group_num);
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
ptr = cruft;
- os_memcpy(ptr, &data->group_num, sizeof(u16));
+ os_memcpy(ptr, &grp, sizeof(u16));
ptr += sizeof(u16);
*ptr = EAP_PWD_DEFAULT_RAND_FUNC;
ptr += sizeof(u8);
*ptr = EAP_PWD_DEFAULT_PRF;
ptr += sizeof(u8);
- H_Update(&ctx, cruft, ptr-cruft);
+ eap_pwd_h_update(hash, cruft, ptr - cruft);
/* all done with the random function */
- H_Final(&ctx, conf);
+ eap_pwd_h_final(hash, conf);
+ os_memcpy(data->my_confirm, conf, SHA256_MAC_LEN);
- req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
- sizeof(struct eap_pwd_hdr) + SHA256_DIGEST_LENGTH,
- EAP_CODE_REQUEST, id);
- if (req == NULL)
+ data->outbuf = wpabuf_alloc(SHA256_MAC_LEN);
+ if (data->outbuf == NULL)
goto fin;
- wpabuf_put_u8(req, EAP_PWD_OPCODE_CONFIRM_EXCH);
- wpabuf_put_data(req, conf, SHA256_DIGEST_LENGTH);
+ wpabuf_put_data(data->outbuf, conf, SHA256_MAC_LEN);
fin:
- os_free(cruft);
- BN_free(x);
- BN_free(y);
- if (req == NULL)
+ bin_clear_free(cruft, BN_num_bytes(data->grp->prime));
+ BN_clear_free(x);
+ BN_clear_free(y);
+ if (data->outbuf == NULL)
eap_pwd_state(data, FAILURE);
-
- return req;
}
eap_pwd_build_req(struct eap_sm *sm, void *priv, u8 id)
{
struct eap_pwd_data *data = priv;
+ struct wpabuf *req;
+ u8 lm_exch;
+ const u8 *buf;
+ u16 totlen = 0;
+ size_t len;
+ /*
+ * if we're buffering response fragments then just ACK
+ */
+ if (data->in_frag_pos) {
+ wpa_printf(MSG_DEBUG, "EAP-pwd: ACKing a fragment!!");
+ req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+ EAP_PWD_HDR_SIZE, EAP_CODE_REQUEST, id);
+ if (req == NULL) {
+ eap_pwd_state(data, FAILURE);
+ return NULL;
+ }
+ switch (data->state) {
+ case PWD_ID_Req:
+ wpabuf_put_u8(req, EAP_PWD_OPCODE_ID_EXCH);
+ break;
+ case PWD_Commit_Req:
+ wpabuf_put_u8(req, EAP_PWD_OPCODE_COMMIT_EXCH);
+ break;
+ case PWD_Confirm_Req:
+ wpabuf_put_u8(req, EAP_PWD_OPCODE_CONFIRM_EXCH);
+ break;
+ default:
+ eap_pwd_state(data, FAILURE); /* just to be sure */
+ wpabuf_free(req);
+ return NULL;
+ }
+ return req;
+ }
+
+ /*
+ * build the data portion of a request
+ */
switch (data->state) {
- case PWD_ID_Req:
- return eap_pwd_build_id_req(sm, data, id);
- case PWD_Commit_Req:
- return eap_pwd_build_commit_req(sm, data, id);
- case PWD_Confirm_Req:
- return eap_pwd_build_confirm_req(sm, data, id);
- default:
+ case PWD_ID_Req:
+ eap_pwd_build_id_req(sm, data, id);
+ lm_exch = EAP_PWD_OPCODE_ID_EXCH;
+ break;
+ case PWD_Commit_Req:
+ eap_pwd_build_commit_req(sm, data, id);
+ lm_exch = EAP_PWD_OPCODE_COMMIT_EXCH;
+ break;
+ case PWD_Confirm_Req:
+ eap_pwd_build_confirm_req(sm, data, id);
+ lm_exch = EAP_PWD_OPCODE_CONFIRM_EXCH;
+ break;
+ default:
wpa_printf(MSG_INFO, "EAP-pwd: Unknown state %d in build_req",
data->state);
+ eap_pwd_state(data, FAILURE);
+ lm_exch = 0; /* hush now, sweet compiler */
break;
}
- return NULL;
+ if (data->state == FAILURE)
+ return NULL;
+
+ /*
+ * determine whether that data needs to be fragmented
+ */
+ len = wpabuf_len(data->outbuf) - data->out_frag_pos;
+ if ((len + EAP_PWD_HDR_SIZE) > data->mtu) {
+ len = data->mtu - EAP_PWD_HDR_SIZE;
+ EAP_PWD_SET_MORE_BIT(lm_exch);
+ /*
+ * if this is the first fragment, need to set the M bit
+ * and add the total length to the eap_pwd_hdr
+ */
+ if (data->out_frag_pos == 0) {
+ EAP_PWD_SET_LENGTH_BIT(lm_exch);
+ totlen = wpabuf_len(data->outbuf) +
+ EAP_PWD_HDR_SIZE + sizeof(u16);
+ len -= sizeof(u16);
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Fragmenting output, "
+ "total length = %d", totlen);
+ }
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Send a %d byte fragment",
+ (int) len);
+ }
+
+ /*
+ * alloc an eap request and populate it with the data
+ */
+ req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
+ EAP_PWD_HDR_SIZE + len +
+ (totlen ? sizeof(u16) : 0),
+ EAP_CODE_REQUEST, id);
+ if (req == NULL) {
+ eap_pwd_state(data, FAILURE);
+ return NULL;
+ }
+
+ wpabuf_put_u8(req, lm_exch);
+ if (EAP_PWD_GET_LENGTH_BIT(lm_exch))
+ wpabuf_put_be16(req, totlen);
+
+ buf = wpabuf_head_u8(data->outbuf);
+ wpabuf_put_data(req, buf + data->out_frag_pos, len);
+ data->out_frag_pos += len;
+ /*
+ * either not fragged or last fragment, either way free up the data
+ */
+ if (data->out_frag_pos >= wpabuf_len(data->outbuf)) {
+ wpabuf_free(data->outbuf);
+ data->outbuf = NULL;
+ data->out_frag_pos = 0;
+ }
+
+ return req;
}
return TRUE;
}
- wpa_printf(MSG_DEBUG, "EAP-pwd: Received frame: opcode=%d", *pos);
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Received frame: exch = %d, len = %d",
+ EAP_PWD_GET_EXCHANGE(*pos), (int) len);
- if (data->state == PWD_ID_Req && *pos == EAP_PWD_OPCODE_ID_EXCH)
+ if (data->state == PWD_ID_Req &&
+ ((EAP_PWD_GET_EXCHANGE(*pos)) == EAP_PWD_OPCODE_ID_EXCH))
return FALSE;
if (data->state == PWD_Commit_Req &&
- *pos == EAP_PWD_OPCODE_COMMIT_EXCH)
+ ((EAP_PWD_GET_EXCHANGE(*pos)) == EAP_PWD_OPCODE_COMMIT_EXCH))
return FALSE;
if (data->state == PWD_Confirm_Req &&
- *pos == EAP_PWD_OPCODE_CONFIRM_EXCH)
+ ((EAP_PWD_GET_EXCHANGE(*pos)) == EAP_PWD_OPCODE_CONFIRM_EXCH))
return FALSE;
wpa_printf(MSG_INFO, "EAP-pwd: Unexpected opcode=%d in state=%d",
const u8 *payload, size_t payload_len)
{
struct eap_pwd_id *id;
+ const u8 *password;
+ size_t password_len;
+ u8 pwhashhash[16];
+ int res;
if (payload_len < sizeof(struct eap_pwd_id)) {
wpa_printf(MSG_INFO, "EAP-pwd: Invalid ID response");
wpa_hexdump_ascii(MSG_DEBUG, "EAP-PWD (server): peer sent id of",
data->id_peer, data->id_peer_len);
- if ((data->grp = os_malloc(sizeof(EAP_PWD_group))) == NULL) {
+ data->grp = os_zalloc(sizeof(EAP_PWD_group));
+ if (data->grp == NULL) {
wpa_printf(MSG_INFO, "EAP-PWD: failed to allocate memory for "
"group");
return;
}
- 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,
- (u8 *) &data->token)) {
+
+ if (data->password_hash) {
+ res = hash_nt_password_hash(data->password, pwhashhash);
+ if (res)
+ return;
+ password = pwhashhash;
+ password_len = sizeof(pwhashhash);
+ } else {
+ password = data->password;
+ password_len = data->password_len;
+ }
+
+ res = compute_password_element(data->grp, data->group_num,
+ password, password_len,
+ data->id_server, data->id_server_len,
+ data->id_peer, data->id_peer_len,
+ (u8 *) &data->token);
+ os_memset(pwhashhash, 0, sizeof(pwhashhash));
+ if (res) {
wpa_printf(MSG_INFO, "EAP-PWD (server): unable to compute "
"PWE");
return;
BIGNUM *x = NULL, *y = NULL, *cofactor = NULL;
EC_POINT *K = NULL, *point = NULL;
int res = 0;
+ size_t prime_len, order_len;
wpa_printf(MSG_DEBUG, "EAP-pwd: Received commit response");
+ prime_len = BN_num_bytes(data->grp->prime);
+ order_len = BN_num_bytes(data->grp->order);
+
+ if (payload_len != 2 * prime_len + order_len) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
+ (unsigned int) payload_len,
+ (unsigned int) (2 * prime_len + order_len));
+ goto fin;
+ }
+
if (((data->peer_scalar = BN_new()) == NULL) ||
((data->k = BN_new()) == NULL) ||
((cofactor = BN_new()) == NULL) ||
res = 1;
fin:
- EC_POINT_free(K);
- EC_POINT_free(point);
- BN_free(cofactor);
- BN_free(x);
- BN_free(y);
+ EC_POINT_clear_free(K);
+ EC_POINT_clear_free(point);
+ BN_clear_free(cofactor);
+ BN_clear_free(x);
+ BN_clear_free(y);
if (res)
eap_pwd_state(data, PWD_Confirm_Req);
const u8 *payload, size_t payload_len)
{
BIGNUM *x = NULL, *y = NULL;
- HMAC_CTX ctx;
+ struct crypto_hash *hash;
u32 cs;
- u8 conf[SHA256_DIGEST_LENGTH], *cruft = NULL, *ptr;
+ u16 grp;
+ u8 conf[SHA256_MAC_LEN], *cruft = NULL, *ptr;
+ int offset;
+
+ if (payload_len != SHA256_MAC_LEN) {
+ wpa_printf(MSG_INFO,
+ "EAP-pwd: Unexpected Confirm payload length %u (expected %u)",
+ (unsigned int) payload_len, SHA256_MAC_LEN);
+ goto fin;
+ }
/* build up the ciphersuite: group | random_function | prf */
+ grp = htons(data->group_num);
ptr = (u8 *) &cs;
- os_memcpy(ptr, &data->group_num, sizeof(u16));
+ os_memcpy(ptr, &grp, sizeof(u16));
ptr += sizeof(u16);
*ptr = EAP_PWD_DEFAULT_RAND_FUNC;
ptr += sizeof(u8);
* commit is H(k | peer_element | peer_scalar | server_element |
* server_scalar | ciphersuite)
*/
- H_Init(&ctx);
+ hash = eap_pwd_h_init();
+ if (hash == NULL)
+ goto fin;
/* 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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(data->k);
+ BN_bn2bin(data->k, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->prime));
/* peer element: x, y */
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+ BN_bn2bin(x, cruft + offset);
+ eap_pwd_h_update(hash, 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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+ BN_bn2bin(y, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->prime));
/* peer scalar */
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
- BN_bn2bin(data->peer_scalar, cruft);
- H_Update(&ctx, cruft, BN_num_bytes(data->grp->order));
+ offset = BN_num_bytes(data->grp->order) -
+ BN_num_bytes(data->peer_scalar);
+ BN_bn2bin(data->peer_scalar, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->order));
/* server element: x, y */
if (!EC_POINT_get_affine_coordinates_GFp(data->grp->group,
}
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
- BN_bn2bin(x, cruft);
- H_Update(&ctx, cruft, BN_num_bytes(data->grp->prime));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(x);
+ BN_bn2bin(x, cruft + offset);
+ eap_pwd_h_update(hash, 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));
+ offset = BN_num_bytes(data->grp->prime) - BN_num_bytes(y);
+ BN_bn2bin(y, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->prime));
/* server 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));
+ offset = BN_num_bytes(data->grp->order) -
+ BN_num_bytes(data->my_scalar);
+ BN_bn2bin(data->my_scalar, cruft + offset);
+ eap_pwd_h_update(hash, cruft, BN_num_bytes(data->grp->order));
/* ciphersuite */
os_memset(cruft, 0, BN_num_bytes(data->grp->prime));
- H_Update(&ctx, (u8 *)&cs, sizeof(u32));
+ eap_pwd_h_update(hash, (u8 *) &cs, sizeof(u32));
/* all done */
- H_Final(&ctx, conf);
+ eap_pwd_h_final(hash, conf);
ptr = (u8 *) payload;
- if (os_memcmp(conf, ptr, SHA256_DIGEST_LENGTH)) {
+ if (os_memcmp_const(conf, ptr, SHA256_MAC_LEN)) {
wpa_printf(MSG_INFO, "EAP-PWD (server): confirm did not "
"verify");
goto fin;
}
wpa_printf(MSG_DEBUG, "EAP-pwd (server): confirm verified");
- if (compute_keys(data->grp, data->bnctx, data->k, data->my_element,
- data->peer_element, data->my_scalar,
- data->peer_scalar, &cs, data->msk, data->emsk) < 0)
+ if (compute_keys(data->grp, data->bnctx, data->k,
+ data->peer_scalar, data->my_scalar, conf,
+ data->my_confirm, &cs, data->msk, data->emsk,
+ data->session_id) < 0)
eap_pwd_state(data, FAILURE);
else
eap_pwd_state(data, SUCCESS);
fin:
- os_free(cruft);
- BN_free(x);
- BN_free(y);
+ bin_clear_free(cruft, BN_num_bytes(data->grp->prime));
+ BN_clear_free(x);
+ BN_clear_free(y);
}
struct eap_pwd_data *data = priv;
const u8 *pos;
size_t len;
- u8 exch;
+ u8 lm_exch;
+ u16 tot_len;
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, respData, &len);
if ((pos == NULL) || (len < 1)) {
return;
}
- exch = *pos & 0x3f;
- switch (exch) {
+ lm_exch = *pos;
+ pos++; /* skip over the bits and the exch */
+ len--;
+
+ /*
+ * if we're fragmenting then this should be an ACK with no data,
+ * just return and continue fragmenting in the "build" section above
+ */
+ if (data->out_frag_pos) {
+ if (len > 1)
+ wpa_printf(MSG_INFO, "EAP-pwd: Bad response! "
+ "Fragmenting but not an ACK");
+ else
+ wpa_printf(MSG_DEBUG, "EAP-pwd: received ACK from "
+ "peer");
+ return;
+ }
+ /*
+ * if we're receiving fragmented packets then we need to buffer...
+ *
+ * the first fragment has a total length
+ */
+ if (EAP_PWD_GET_LENGTH_BIT(lm_exch)) {
+ if (len < 2) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: Frame too short to contain Total-Length field");
+ return;
+ }
+ tot_len = WPA_GET_BE16(pos);
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Incoming fragments, total "
+ "length = %d", tot_len);
+ if (tot_len > 15000)
+ return;
+ if (data->inbuf) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: Unexpected new fragment start when previous fragment is still in use");
+ return;
+ }
+ data->inbuf = wpabuf_alloc(tot_len);
+ if (data->inbuf == NULL) {
+ wpa_printf(MSG_INFO, "EAP-pwd: Out of memory to "
+ "buffer fragments!");
+ return;
+ }
+ data->in_frag_pos = 0;
+ pos += sizeof(u16);
+ len -= sizeof(u16);
+ }
+ /*
+ * the first and all intermediate fragments have the M bit set
+ */
+ if (EAP_PWD_GET_MORE_BIT(lm_exch)) {
+ if ((data->in_frag_pos + len) > wpabuf_size(data->inbuf)) {
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Buffer overflow "
+ "attack detected! (%d+%d > %d)",
+ (int) data->in_frag_pos, (int) len,
+ (int) wpabuf_size(data->inbuf));
+ eap_pwd_state(data, FAILURE);
+ return;
+ }
+ wpabuf_put_data(data->inbuf, pos, len);
+ data->in_frag_pos += len;
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Got a %d byte fragment",
+ (int) len);
+ return;
+ }
+ /*
+ * last fragment won't have the M bit set (but we're obviously
+ * buffering fragments so that's how we know it's the last)
+ */
+ if (data->in_frag_pos) {
+ wpabuf_put_data(data->inbuf, pos, len);
+ data->in_frag_pos += len;
+ pos = wpabuf_head_u8(data->inbuf);
+ len = data->in_frag_pos;
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",
+ (int) len);
+ }
+ switch (EAP_PWD_GET_EXCHANGE(lm_exch)) {
case EAP_PWD_OPCODE_ID_EXCH:
- eap_pwd_process_id_resp(sm, data, pos + 1, len - 1);
+ eap_pwd_process_id_resp(sm, data, pos, len);
break;
case EAP_PWD_OPCODE_COMMIT_EXCH:
- eap_pwd_process_commit_resp(sm, data, pos + 1, len - 1);
+ eap_pwd_process_commit_resp(sm, data, pos, len);
break;
- case EAP_PWD_OPCODE_CONFIRM_EXCH:
- eap_pwd_process_confirm_resp(sm, data, pos + 1, len - 1);
+ case EAP_PWD_OPCODE_CONFIRM_EXCH:
+ eap_pwd_process_confirm_resp(sm, data, pos, len);
break;
}
+ /*
+ * if we had been buffering fragments, here's a great place
+ * to clean up
+ */
+ if (data->in_frag_pos) {
+ wpabuf_free(data->inbuf);
+ data->inbuf = NULL;
+ data->in_frag_pos = 0;
+ }
}
}
+static u8 * eap_pwd_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_pwd_data *data = priv;
+ u8 *id;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ id = os_malloc(1 + SHA256_MAC_LEN);
+ if (id == NULL)
+ return NULL;
+
+ os_memcpy(id, data->session_id, 1 + SHA256_MAC_LEN);
+ *len = 1 + SHA256_MAC_LEN;
+
+ return id;
+}
+
+
int eap_server_pwd_register(void)
{
struct eap_method *eap;
struct timezone tz;
u32 sr;
- EVP_add_digest(EVP_sha256());
-
sr = 0xdeaddada;
(void) gettimeofday(&tp, &tz);
sr ^= (tp.tv_sec ^ tp.tv_usec);
eap->getKey = eap_pwd_getkey;
eap->get_emsk = eap_pwd_get_emsk;
eap->isSuccess = eap_pwd_is_success;
+ eap->getSessionId = eap_pwd_get_session_id;
ret = eap_server_method_register(eap);
if (ret)
projects / mech_eap.git / blobdiff