diff options
Diffstat (limited to 'contrib/hostapd/eap_pax.c')
-rw-r--r-- | contrib/hostapd/eap_pax.c | 519 |
1 files changed, 519 insertions, 0 deletions
diff --git a/contrib/hostapd/eap_pax.c b/contrib/hostapd/eap_pax.c new file mode 100644 index 0000000..2fbec87 --- /dev/null +++ b/contrib/hostapd/eap_pax.c @@ -0,0 +1,519 @@ +/* + * hostapd / EAP-PAX (draft-clancy-eap-pax-04.txt) server + * Copyright (c) 2005, Jouni Malinen <jkmaline@cc.hut.fi> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Alternatively, this software may be distributed under the terms of BSD + * license. + * + * See README and COPYING for more details. + */ + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <netinet/in.h> + +#include "hostapd.h" +#include "common.h" +#include "eap_i.h" +#include "eap_pax_common.h" + +/* + * Note: only PAX_STD subprotocol is currently supported + */ + +struct eap_pax_data { + enum { PAX_STD_1, PAX_STD_3, SUCCESS, FAILURE } state; + u8 mac_id; + union { + u8 e[2 * EAP_PAX_RAND_LEN]; + struct { + u8 x[EAP_PAX_RAND_LEN]; /* server rand */ + u8 y[EAP_PAX_RAND_LEN]; /* client rand */ + } r; + } rand; + u8 ak[EAP_PAX_AK_LEN]; + u8 mk[EAP_PAX_MK_LEN]; + u8 ck[EAP_PAX_CK_LEN]; + u8 ick[EAP_PAX_ICK_LEN]; + int keys_set; + char *cid; + size_t cid_len; +}; + + +static void * eap_pax_init(struct eap_sm *sm) +{ + struct eap_pax_data *data; + + data = malloc(sizeof(*data)); + if (data == NULL) + return data; + memset(data, 0, sizeof(*data)); + data->state = PAX_STD_1; + /* + * TODO: make this configurable once EAP_PAX_MAC_AES_CBC_MAC_128 is + * supported + */ + data->mac_id = EAP_PAX_MAC_HMAC_SHA1_128; + + return data; +} + + +static void eap_pax_reset(struct eap_sm *sm, void *priv) +{ + struct eap_pax_data *data = priv; + free(data->cid); + free(data); +} + + +static u8 * eap_pax_build_std_1(struct eap_sm *sm, + struct eap_pax_data *data, + int id, size_t *reqDataLen) +{ + struct eap_pax_hdr *req; + u8 *pos; + + wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-1 (sending)"); + + if (hostapd_get_rand(data->rand.r.x, EAP_PAX_RAND_LEN)) { + wpa_printf(MSG_ERROR, "EAP-PAX: Failed to get random data"); + data->state = FAILURE; + return NULL; + } + + *reqDataLen = sizeof(*req) + 2 + EAP_PAX_RAND_LEN + EAP_PAX_ICV_LEN; + req = malloc(*reqDataLen); + if (req == NULL) { + wpa_printf(MSG_ERROR, "EAP-PAX: Failed to allocate memory " + "request"); + data->state = FAILURE; + return NULL; + } + + req->code = EAP_CODE_REQUEST; + req->identifier = id; + req->length = htons(*reqDataLen); + req->type = EAP_TYPE_PAX; + req->op_code = EAP_PAX_OP_STD_1; + req->flags = 0; + req->mac_id = data->mac_id; + req->dh_group_id = EAP_PAX_DH_GROUP_NONE; + req->public_key_id = EAP_PAX_PUBLIC_KEY_NONE; + pos = (u8 *) (req + 1); + *pos++ = 0; + *pos++ = EAP_PAX_RAND_LEN; + memcpy(pos, data->rand.r.x, EAP_PAX_RAND_LEN); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: A = X (server rand)", + pos, EAP_PAX_RAND_LEN); + pos += EAP_PAX_RAND_LEN; + + eap_pax_mac(data->mac_id, (u8 *) "", 0, + (u8 *) req, *reqDataLen - EAP_PAX_ICV_LEN, + NULL, 0, NULL, 0, pos); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN); + pos += EAP_PAX_ICV_LEN; + + return (u8 *) req; +} + + +static u8 * eap_pax_build_std_3(struct eap_sm *sm, + struct eap_pax_data *data, + int id, size_t *reqDataLen) +{ + struct eap_pax_hdr *req; + u8 *pos; + + wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-3 (sending)"); + + *reqDataLen = sizeof(*req) + 2 + EAP_PAX_MAC_LEN + EAP_PAX_ICV_LEN; + req = malloc(*reqDataLen); + if (req == NULL) { + wpa_printf(MSG_ERROR, "EAP-PAX: Failed to allocate memory " + "request"); + data->state = FAILURE; + return NULL; + } + + req->code = EAP_CODE_REQUEST; + req->identifier = id; + req->length = htons(*reqDataLen); + req->type = EAP_TYPE_PAX; + req->op_code = EAP_PAX_OP_STD_3; + req->flags = 0; + req->mac_id = data->mac_id; + req->dh_group_id = EAP_PAX_DH_GROUP_NONE; + req->public_key_id = EAP_PAX_PUBLIC_KEY_NONE; + pos = (u8 *) (req + 1); + *pos++ = 0; + *pos++ = EAP_PAX_MAC_LEN; + eap_pax_mac(data->mac_id, data->ck, EAP_PAX_CK_LEN, + data->rand.r.y, EAP_PAX_RAND_LEN, + (u8 *) data->cid, data->cid_len, NULL, 0, pos); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: MAC_CK(B, CID)", + pos, EAP_PAX_MAC_LEN); + pos += EAP_PAX_MAC_LEN; + + eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN, + (u8 *) req, *reqDataLen - EAP_PAX_ICV_LEN, + NULL, 0, NULL, 0, pos); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN); + pos += EAP_PAX_ICV_LEN; + + return (u8 *) req; +} + + +static u8 * eap_pax_buildReq(struct eap_sm *sm, void *priv, int id, + size_t *reqDataLen) +{ + struct eap_pax_data *data = priv; + + switch (data->state) { + case PAX_STD_1: + return eap_pax_build_std_1(sm, data, id, reqDataLen); + case PAX_STD_3: + return eap_pax_build_std_3(sm, data, id, reqDataLen); + default: + wpa_printf(MSG_DEBUG, "EAP-PAX: Unknown state %d in buildReq", + data->state); + break; + } + return NULL; +} + + +static Boolean eap_pax_check(struct eap_sm *sm, void *priv, + u8 *respData, size_t respDataLen) +{ + struct eap_pax_data *data = priv; + struct eap_pax_hdr *resp; + size_t len; + u8 icvbuf[EAP_PAX_ICV_LEN], *icv; + + resp = (struct eap_pax_hdr *) respData; + if (respDataLen < sizeof(*resp) || resp->type != EAP_TYPE_PAX || + (len = ntohs(resp->length)) > respDataLen || + len < sizeof(*resp) + EAP_PAX_ICV_LEN) { + wpa_printf(MSG_INFO, "EAP-PAX: Invalid frame"); + return TRUE; + } + + wpa_printf(MSG_DEBUG, "EAP-PAX: received frame: op_code 0x%x " + "flags 0x%x mac_id 0x%x dh_group_id 0x%x " + "public_key_id 0x%x", + resp->op_code, resp->flags, resp->mac_id, resp->dh_group_id, + resp->public_key_id); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: received payload", + (u8 *) (resp + 1), len - sizeof(*resp) - EAP_PAX_ICV_LEN); + + if (data->state == PAX_STD_1 && + resp->op_code != EAP_PAX_OP_STD_2) { + wpa_printf(MSG_DEBUG, "EAP-PAX: Expected PAX_STD-2 - " + "ignore op %d", resp->op_code); + return TRUE; + } + + if (data->state == PAX_STD_3 && + resp->op_code != EAP_PAX_OP_ACK) { + wpa_printf(MSG_DEBUG, "EAP-PAX: Expected PAX-ACK - " + "ignore op %d", resp->op_code); + return TRUE; + } + + if (resp->op_code != EAP_PAX_OP_STD_2 && + resp->op_code != EAP_PAX_OP_ACK) { + wpa_printf(MSG_DEBUG, "EAP-PAX: Unknown op_code 0x%x", + resp->op_code); + } + + if (data->mac_id != resp->mac_id) { + wpa_printf(MSG_DEBUG, "EAP-PAX: Expected MAC ID 0x%x, " + "received 0x%x", data->mac_id, resp->mac_id); + return TRUE; + } + + if (resp->dh_group_id != EAP_PAX_DH_GROUP_NONE) { + wpa_printf(MSG_INFO, "EAP-PAX: Expected DH Group ID 0x%x, " + "received 0x%x", EAP_PAX_DH_GROUP_NONE, + resp->dh_group_id); + return TRUE; + } + + if (resp->public_key_id != EAP_PAX_PUBLIC_KEY_NONE) { + wpa_printf(MSG_INFO, "EAP-PAX: Expected Public Key ID 0x%x, " + "received 0x%x", EAP_PAX_PUBLIC_KEY_NONE, + resp->public_key_id); + return TRUE; + } + + if (resp->flags & EAP_PAX_FLAGS_MF) { + /* TODO: add support for reassembling fragments */ + wpa_printf(MSG_INFO, "EAP-PAX: fragmentation not supported"); + return TRUE; + } + + if (resp->flags & EAP_PAX_FLAGS_CE) { + wpa_printf(MSG_INFO, "EAP-PAX: Unexpected CE flag"); + return TRUE; + } + + if (data->keys_set) { + if (len - sizeof(*resp) < EAP_PAX_ICV_LEN) { + wpa_printf(MSG_INFO, "EAP-PAX: No ICV in the packet"); + return TRUE; + } + icv = respData + len - EAP_PAX_ICV_LEN; + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", icv, EAP_PAX_ICV_LEN); + eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN, + respData, len - EAP_PAX_ICV_LEN, NULL, 0, NULL, 0, + icvbuf); + if (memcmp(icvbuf, icv, EAP_PAX_ICV_LEN) != 0) { + wpa_printf(MSG_INFO, "EAP-PAX: Invalid ICV"); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected ICV", + icvbuf, EAP_PAX_ICV_LEN); + return TRUE; + } + } + + return FALSE; +} + + +static void eap_pax_process_std_2(struct eap_sm *sm, + struct eap_pax_data *data, + u8 *respData, size_t respDataLen) +{ + struct eap_pax_hdr *resp; + u8 *pos, mac[EAP_PAX_MAC_LEN], icvbuf[EAP_PAX_ICV_LEN]; + size_t len, left; + int i; + + if (data->state != PAX_STD_1) + return; + + wpa_printf(MSG_DEBUG, "EAP-PAX: Received PAX_STD-2"); + + resp = (struct eap_pax_hdr *) respData; + len = ntohs(resp->length); + pos = (u8 *) (resp + 1); + left = len - sizeof(*resp); + + if (left < 2 + EAP_PAX_RAND_LEN || + ((pos[0] << 8) | pos[1]) != EAP_PAX_RAND_LEN) { + wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (B)"); + return; + } + pos += 2; + left -= 2; + memcpy(data->rand.r.y, pos, EAP_PAX_RAND_LEN); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Y (client rand)", + data->rand.r.y, EAP_PAX_RAND_LEN); + pos += EAP_PAX_RAND_LEN; + left -= EAP_PAX_RAND_LEN; + + if (left < 2 || 2 + ((pos[0] << 8) | pos[1]) > left) { + wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (CID)"); + return; + } + data->cid_len = (pos[0] << 8) | pos[1]; + free(data->cid); + data->cid = malloc(data->cid_len); + if (data->cid == NULL) { + wpa_printf(MSG_INFO, "EAP-PAX: Failed to allocate memory for " + "CID"); + return; + } + memcpy (data->cid, pos + 2, data->cid_len); + pos += 2 + data->cid_len; + left -= 2 + data->cid_len; + wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-PAX: CID", + (u8 *) data->cid, data->cid_len); + + if (left < 2 + EAP_PAX_MAC_LEN || + ((pos[0] << 8) | pos[1]) != EAP_PAX_MAC_LEN) { + wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (MAC_CK)"); + return; + } + pos += 2; + left -= 2; + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: MAC_CK(A, B, CID)", + pos, EAP_PAX_MAC_LEN); + + if (eap_user_get(sm, (u8 *) data->cid, data->cid_len, 0) < 0) { + wpa_hexdump_ascii(MSG_DEBUG, "EAP-PAX: unknown CID", + (u8 *) data->cid, data->cid_len); + data->state = FAILURE; + return; + } + + for (i = 0; + i < EAP_MAX_METHODS && sm->user->methods[i] != EAP_TYPE_NONE; + i++) { + if (sm->user->methods[i] == EAP_TYPE_PAX) + break; + } + + if (sm->user->methods[i] != EAP_TYPE_PAX) { + wpa_hexdump_ascii(MSG_DEBUG, + "EAP-PAX: EAP-PAX not enabled for CID", + (u8 *) data->cid, data->cid_len); + data->state = FAILURE; + return; + } + + if (sm->user->password == NULL || + sm->user->password_len != EAP_PAX_AK_LEN) { + wpa_hexdump_ascii(MSG_DEBUG, "EAP-PAX: invalid password in " + "user database for CID", + (u8 *) data->cid, data->cid_len); + data->state = FAILURE; + return; + } + memcpy(data->ak, sm->user->password, EAP_PAX_AK_LEN); + + if (eap_pax_initial_key_derivation(data->mac_id, data->ak, + data->rand.e, data->mk, data->ck, + data->ick) < 0) { + wpa_printf(MSG_INFO, "EAP-PAX: Failed to complete initial " + "key derivation"); + data->state = FAILURE; + return; + } + data->keys_set = 1; + + eap_pax_mac(data->mac_id, data->ck, EAP_PAX_CK_LEN, + data->rand.r.x, EAP_PAX_RAND_LEN, + data->rand.r.y, EAP_PAX_RAND_LEN, + (u8 *) data->cid, data->cid_len, mac); + if (memcmp(mac, pos, EAP_PAX_MAC_LEN) != 0) { + wpa_printf(MSG_INFO, "EAP-PAX: Invalid MAC_CK(A, B, CID) in " + "PAX_STD-2"); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected MAC_CK(A, B, CID)", + mac, EAP_PAX_MAC_LEN); + data->state = FAILURE; + return; + } + + pos += EAP_PAX_MAC_LEN; + left -= EAP_PAX_MAC_LEN; + + if (left < EAP_PAX_ICV_LEN) { + wpa_printf(MSG_INFO, "EAP-PAX: Too short ICV (%lu) in " + "PAX_STD-2", (unsigned long) left); + return; + } + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN); + eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN, + respData, len - EAP_PAX_ICV_LEN, NULL, 0, NULL, 0, icvbuf); + if (memcmp(icvbuf, pos, EAP_PAX_ICV_LEN) != 0) { + wpa_printf(MSG_INFO, "EAP-PAX: Invalid ICV in PAX_STD-2"); + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected ICV", + icvbuf, EAP_PAX_ICV_LEN); + return; + } + pos += EAP_PAX_ICV_LEN; + left -= EAP_PAX_ICV_LEN; + + if (left > 0) { + wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ignored extra payload", + pos, left); + } + + data->state = PAX_STD_3; +} + + +static void eap_pax_process_ack(struct eap_sm *sm, + struct eap_pax_data *data, + u8 *respData, size_t respDataLen) +{ + if (data->state != PAX_STD_3) + return; + + wpa_printf(MSG_DEBUG, "EAP-PAX: Received PAX-ACK - authentication " + "completed successfully"); + data->state = SUCCESS; +} + + +static void eap_pax_process(struct eap_sm *sm, void *priv, + u8 *respData, size_t respDataLen) +{ + struct eap_pax_data *data = priv; + struct eap_pax_hdr *resp; + + if (sm->user == NULL || sm->user->password == NULL) { + wpa_printf(MSG_INFO, "EAP-MSCHAPV2: Password not configured"); + data->state = FAILURE; + return; + } + + resp = (struct eap_pax_hdr *) respData; + + switch (resp->op_code) { + case EAP_PAX_OP_STD_2: + eap_pax_process_std_2(sm, data, respData, respDataLen); + break; + case EAP_PAX_OP_ACK: + eap_pax_process_ack(sm, data, respData, respDataLen); + break; + } +} + + +static Boolean eap_pax_isDone(struct eap_sm *sm, void *priv) +{ + struct eap_pax_data *data = priv; + return data->state == SUCCESS || data->state == FAILURE; +} + + +static u8 * eap_pax_getKey(struct eap_sm *sm, void *priv, size_t *len) +{ + struct eap_pax_data *data = priv; + u8 *key; + + if (data->state != SUCCESS) + return NULL; + + key = malloc(EAP_PAX_MSK_LEN); + if (key == NULL) + return NULL; + + *len = EAP_PAX_MSK_LEN; + eap_pax_kdf(data->mac_id, data->mk, EAP_PAX_MK_LEN, + "Master Session Key", data->rand.e, 2 * EAP_PAX_RAND_LEN, + EAP_PAX_MSK_LEN, key); + + return key; +} + + +static Boolean eap_pax_isSuccess(struct eap_sm *sm, void *priv) +{ + struct eap_pax_data *data = priv; + return data->state == SUCCESS; +} + + +const struct eap_method eap_method_pax = +{ + .method = EAP_TYPE_PAX, + .name = "PAX", + .init = eap_pax_init, + .reset = eap_pax_reset, + .buildReq = eap_pax_buildReq, + .check = eap_pax_check, + .process = eap_pax_process, + .isDone = eap_pax_isDone, + .getKey = eap_pax_getKey, + .isSuccess = eap_pax_isSuccess, +}; |