From 0744e303cfd20f571ed11774702bf4116d0b8f12 Mon Sep 17 00:00:00 2001 From: Dan Harkins Date: Fri, 25 May 2018 21:40:04 +0300 Subject: [PATCH] EAP-pwd peer: Move PWE derivation to commit exchange There is no need to do this during the ID exchange, so move PWE deriation into the following commit exchange in preparation for adding support for salted passwords. Signed-off-by: Dan Harkins --- src/eap_peer/eap_pwd.c | 114 +++++++++++++++++++++++------------------ 1 file changed, 63 insertions(+), 51 deletions(-) diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c index ae0f9a47c..3c5d5a816 100644 --- a/src/eap_peer/eap_pwd.c +++ b/src/eap_peer/eap_pwd.c @@ -29,6 +29,8 @@ struct eap_pwd_data { size_t password_len; int password_hash; u16 group_num; + u8 prep; + u8 token[4]; EAP_PWD_group *grp; struct wpabuf *inbuf; @@ -206,10 +208,6 @@ eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data, 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 (data->state != PWD_ID_Req) { ret->ignore = TRUE; @@ -254,6 +252,9 @@ eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data, wpa_printf(MSG_DEBUG, "EAP-PWD (peer): using group %d", data->group_num); + data->prep = id->prep; + os_memcpy(data->token, id->token, sizeof(id->token)); + 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"); @@ -273,7 +274,63 @@ eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data, return; } - if (id->prep == EAP_PWD_PREP_MS) { + data->outbuf = wpabuf_alloc(sizeof(struct eap_pwd_id) + + data->id_peer_len); + if (data->outbuf == NULL) { + eap_pwd_state(data, FAILURE); + return; + } + 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, id->token, sizeof(id->token)); + wpabuf_put_u8(data->outbuf, id->prep); + wpabuf_put_data(data->outbuf, data->id_peer, data->id_peer_len); + + eap_pwd_state(data, PWD_Commit_Req); +} + + +static void +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 crypto_ec_point *K = NULL, *point = NULL; + struct crypto_bignum *mask = NULL, *cofactor = NULL; + const u8 *ptr; + u8 *scalar = NULL, *element = NULL; + size_t prime_len, order_len; + const u8 *password; + size_t password_len; + u8 pwhashhash[16]; + int res; + + if (data->state != PWD_Commit_Req) { + ret->ignore = TRUE; + goto fin; + } + + if (!data->grp) { + wpa_printf(MSG_DEBUG, + "EAP-PWD (client): uninitialized EAP-pwd group"); + ret->ignore = TRUE; + goto fin; + } + + prime_len = crypto_ec_prime_len(data->grp->group); + order_len = crypto_ec_order_len(data->grp->group); + + 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->prep == EAP_PWD_PREP_MS) { #ifdef CONFIG_FIPS wpa_printf(MSG_ERROR, "EAP-PWD (peer): MS password hash not supported in FIPS mode"); @@ -310,7 +367,7 @@ eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data, password, password_len, data->id_server, data->id_server_len, data->id_peer, data->id_peer_len, - id->token); + data->token); os_memset(pwhashhash, 0, sizeof(pwhashhash)); if (res) { wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute PWE"); @@ -321,51 +378,6 @@ eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data, wpa_printf(MSG_DEBUG, "EAP-PWD (peer): computed %d bit PWE...", (int) crypto_ec_prime_len_bits(data->grp->group)); - data->outbuf = wpabuf_alloc(sizeof(struct eap_pwd_id) + - data->id_peer_len); - if (data->outbuf == NULL) { - eap_pwd_state(data, FAILURE); - return; - } - 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, id->token, sizeof(id->token)); - wpabuf_put_u8(data->outbuf, id->prep); - wpabuf_put_data(data->outbuf, data->id_peer, data->id_peer_len); - - eap_pwd_state(data, PWD_Commit_Req); -} - - -static void -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 crypto_ec_point *K = NULL, *point = NULL; - struct crypto_bignum *mask = NULL, *cofactor = NULL; - const u8 *ptr; - u8 *scalar = NULL, *element = NULL; - size_t prime_len, order_len; - - if (data->state != PWD_Commit_Req) { - ret->ignore = TRUE; - goto fin; - } - - prime_len = crypto_ec_prime_len(data->grp->group); - order_len = crypto_ec_order_len(data->grp->group); - - 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; - } - data->private_value = crypto_bignum_init(); data->my_element = crypto_ec_point_init(data->grp->group); cofactor = crypto_bignum_init();