NetBSD/dist/hostapd/eap_peap.c

727 lines
18 KiB
C

/*
* hostapd / EAP-PEAP (draft-josefsson-pppext-eap-tls-eap-07.txt)
* Copyright (c) 2004-2005, 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_tls_common.h"
#include "tls.h"
/* Maximum supported PEAP version
* 0 = Microsoft's PEAP version 0; draft-kamath-pppext-peapv0-00.txt
* 1 = draft-josefsson-ppext-eap-tls-eap-05.txt
* 2 = draft-josefsson-ppext-eap-tls-eap-07.txt
*/
#define EAP_PEAP_VERSION 1
static void eap_peap_reset(struct eap_sm *sm, void *priv);
struct eap_peap_data {
struct eap_ssl_data ssl;
enum {
START, PHASE1, PHASE2_START, PHASE2_ID, PHASE2_METHOD,
PHASE2_TLV, SUCCESS_REQ, FAILURE_REQ, SUCCESS, FAILURE
} state;
int peap_version;
const struct eap_method *phase2_method;
void *phase2_priv;
int force_version;
};
static const char * eap_peap_state_txt(int state)
{
switch (state) {
case START:
return "START";
case PHASE1:
return "PHASE1";
case PHASE2_START:
return "PHASE2_START";
case PHASE2_ID:
return "PHASE2_ID";
case PHASE2_METHOD:
return "PHASE2_METHOD";
case PHASE2_TLV:
return "PHASE2_TLV";
case SUCCESS_REQ:
return "SUCCESS_REQ";
case FAILURE_REQ:
return "FAILURE_REQ";
case SUCCESS:
return "SUCCESS";
case FAILURE:
return "FAILURE";
default:
return "Unknown?!";
}
}
static void eap_peap_state(struct eap_peap_data *data, int state)
{
wpa_printf(MSG_DEBUG, "EAP-PEAP: %s -> %s",
eap_peap_state_txt(data->state),
eap_peap_state_txt(state));
data->state = state;
}
static EapType eap_peap_req_success(struct eap_sm *sm,
struct eap_peap_data *data)
{
if (data->state == FAILURE || data->state == FAILURE_REQ) {
eap_peap_state(data, FAILURE);
return EAP_TYPE_NONE;
}
if (data->peap_version == 0) {
sm->tlv_request = TLV_REQ_SUCCESS;
eap_peap_state(data, PHASE2_TLV);
return EAP_TYPE_TLV;
} else {
eap_peap_state(data, SUCCESS_REQ);
return EAP_TYPE_NONE;
}
}
static EapType eap_peap_req_failure(struct eap_sm *sm,
struct eap_peap_data *data)
{
if (data->state == FAILURE || data->state == FAILURE_REQ ||
data->state == SUCCESS_REQ ||
(data->phase2_method &&
data->phase2_method->method == EAP_TYPE_TLV)) {
eap_peap_state(data, FAILURE);
return EAP_TYPE_NONE;
}
if (data->peap_version == 0) {
sm->tlv_request = TLV_REQ_FAILURE;
eap_peap_state(data, PHASE2_TLV);
return EAP_TYPE_TLV;
} else {
eap_peap_state(data, FAILURE_REQ);
return EAP_TYPE_NONE;
}
}
static void * eap_peap_init(struct eap_sm *sm)
{
struct eap_peap_data *data;
data = malloc(sizeof(*data));
if (data == NULL)
return data;
memset(data, 0, sizeof(*data));
data->peap_version = EAP_PEAP_VERSION;
data->force_version = -1;
if (sm->user && sm->user->force_version >= 0) {
data->force_version = sm->user->force_version;
wpa_printf(MSG_DEBUG, "EAP-PEAP: forcing version %d",
data->force_version);
data->peap_version = data->force_version;
}
data->state = START;
if (eap_tls_ssl_init(sm, &data->ssl, 0)) {
wpa_printf(MSG_INFO, "EAP-PEAP: Failed to initialize SSL.");
eap_peap_reset(sm, data);
return NULL;
}
return data;
}
static void eap_peap_reset(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
if (data == NULL)
return;
if (data->phase2_priv && data->phase2_method)
data->phase2_method->reset(sm, data->phase2_priv);
eap_tls_ssl_deinit(sm, &data->ssl);
free(data);
}
static u8 * eap_peap_build_start(struct eap_sm *sm, struct eap_peap_data *data,
int id, size_t *reqDataLen)
{
struct eap_hdr *req;
u8 *pos;
*reqDataLen = sizeof(*req) + 2;
req = malloc(*reqDataLen);
if (req == NULL) {
wpa_printf(MSG_ERROR, "EAP-PEAP: Failed to allocate memory for"
" request");
eap_peap_state(data, FAILURE);
return NULL;
}
req->code = EAP_CODE_REQUEST;
req->identifier = id;
req->length = htons(*reqDataLen);
pos = (u8 *) (req + 1);
*pos++ = EAP_TYPE_PEAP;
*pos = EAP_TLS_FLAGS_START | data->peap_version;
eap_peap_state(data, PHASE1);
return (u8 *) req;
}
static u8 * eap_peap_build_req(struct eap_sm *sm, struct eap_peap_data *data,
int id, size_t *reqDataLen)
{
int res;
u8 *req;
res = eap_tls_buildReq_helper(sm, &data->ssl, EAP_TYPE_PEAP,
data->peap_version, id, &req,
reqDataLen);
if (tls_connection_established(sm->ssl_ctx, data->ssl.conn)) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase1 done, starting "
"Phase2");
eap_peap_state(data, PHASE2_START);
}
if (res == 1)
return eap_tls_build_ack(reqDataLen, id, EAP_TYPE_PEAP,
data->peap_version);
return req;
}
static u8 * eap_peap_encrypt(struct eap_sm *sm, struct eap_peap_data *data,
int id, u8 *plain, size_t plain_len,
size_t *out_len)
{
int res;
u8 *pos;
struct eap_hdr *req;
/* TODO: add support for fragmentation, if needed. This will need to
* add TLS Message Length field, if the frame is fragmented. */
req = malloc(sizeof(struct eap_hdr) + 2 + data->ssl.tls_out_limit);
if (req == NULL)
return NULL;
req->code = EAP_CODE_REQUEST;
req->identifier = id;
pos = (u8 *) (req + 1);
*pos++ = EAP_TYPE_PEAP;
*pos++ = data->peap_version;
res = tls_connection_encrypt(sm->ssl_ctx, data->ssl.conn,
plain, plain_len,
pos, data->ssl.tls_out_limit);
if (res < 0) {
wpa_printf(MSG_INFO, "EAP-PEAP: Failed to encrypt Phase 2 "
"data");
free(req);
return NULL;
}
*out_len = sizeof(struct eap_hdr) + 2 + res;
req->length = host_to_be16(*out_len);
return (u8 *) req;
}
static u8 * eap_peap_build_phase2_req(struct eap_sm *sm,
struct eap_peap_data *data,
int id, size_t *reqDataLen)
{
u8 *req, *buf, *encr_req;
size_t req_len;
buf = req = data->phase2_method->buildReq(sm, data->phase2_priv, id,
&req_len);
if (req == NULL)
return NULL;
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: Encrypting Phase 2 data",
req, req_len);
if (data->peap_version == 0 &&
data->phase2_method->method != EAP_TYPE_TLV) {
req += sizeof(struct eap_hdr);
req_len -= sizeof(struct eap_hdr);
}
encr_req = eap_peap_encrypt(sm, data, id, req, req_len, reqDataLen);
free(buf);
return encr_req;
}
static u8 * eap_peap_build_phase2_term(struct eap_sm *sm,
struct eap_peap_data *data,
int id, size_t *reqDataLen, int success)
{
u8 *encr_req;
size_t req_len;
struct eap_hdr *hdr;
req_len = sizeof(*hdr);
hdr = malloc(req_len);
if (hdr == NULL) {
return NULL;
}
memset(hdr, 0, req_len);
hdr->code = success ? EAP_CODE_SUCCESS : EAP_CODE_FAILURE;
hdr->identifier = id;
hdr->length = htons(req_len);
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: Encrypting Phase 2 data",
(u8 *) hdr, req_len);
encr_req = eap_peap_encrypt(sm, data, id, (u8 *) hdr, req_len,
reqDataLen);
free(hdr);
return encr_req;
}
static u8 * eap_peap_buildReq(struct eap_sm *sm, void *priv, int id,
size_t *reqDataLen)
{
struct eap_peap_data *data = priv;
switch (data->state) {
case START:
return eap_peap_build_start(sm, data, id, reqDataLen);
case PHASE1:
return eap_peap_build_req(sm, data, id, reqDataLen);
case PHASE2_ID:
case PHASE2_METHOD:
case PHASE2_TLV:
return eap_peap_build_phase2_req(sm, data, id, reqDataLen);
case SUCCESS_REQ:
return eap_peap_build_phase2_term(sm, data, id, reqDataLen, 1);
case FAILURE_REQ:
return eap_peap_build_phase2_term(sm, data, id, reqDataLen, 0);
default:
wpa_printf(MSG_DEBUG, "EAP-PEAP: %s - unexpected state %d",
__func__, data->state);
return NULL;
}
}
static Boolean eap_peap_check(struct eap_sm *sm, void *priv,
u8 *respData, size_t respDataLen)
{
struct eap_hdr *resp;
u8 *pos;
size_t len;
resp = (struct eap_hdr *) respData;
pos = (u8 *) (resp + 1);
if (respDataLen < sizeof(*resp) + 2 || *pos != EAP_TYPE_PEAP ||
(len = ntohs(resp->length)) > respDataLen) {
wpa_printf(MSG_INFO, "EAP-PEAP: Invalid frame");
return TRUE;
}
return FALSE;
}
static int eap_peap_phase2_init(struct eap_sm *sm, struct eap_peap_data *data,
u8 eap_type)
{
if (data->phase2_priv && data->phase2_method) {
data->phase2_method->reset(sm, data->phase2_priv);
data->phase2_method = NULL;
data->phase2_priv = NULL;
}
data->phase2_method = eap_sm_get_eap_methods(eap_type);
if (!data->phase2_method)
return -1;
sm->init_phase2 = 1;
data->phase2_priv = data->phase2_method->init(sm);
sm->init_phase2 = 0;
return 0;
}
static void eap_peap_process_phase2_response(struct eap_sm *sm,
struct eap_peap_data *data,
u8 *in_data, size_t in_len)
{
u8 next_type = EAP_TYPE_NONE;
struct eap_hdr *hdr;
u8 *pos;
size_t left;
if (data->phase2_priv == NULL) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: %s - Phase2 not "
"initialized?!", __func__);
return;
}
hdr = (struct eap_hdr *) in_data;
pos = (u8 *) (hdr + 1);
left = in_len - sizeof(*hdr);
if (in_len > sizeof(*hdr) && *pos == EAP_TYPE_NAK) {
wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Phase2 type Nak'ed; "
"allowed types", pos + 1, left - 1);
eap_sm_process_nak(sm, pos + 1, left - 1);
if (sm->user && sm->user_eap_method_index < EAP_MAX_METHODS &&
sm->user->methods[sm->user_eap_method_index] !=
EAP_TYPE_NONE) {
next_type =
sm->user->methods[sm->user_eap_method_index++];
wpa_printf(MSG_DEBUG, "EAP-PEAP: try EAP type %d",
next_type);
} else {
next_type = eap_peap_req_failure(sm, data);
}
eap_peap_phase2_init(sm, data, next_type);
return;
}
if (data->phase2_method->check(sm, data->phase2_priv, in_data,
in_len)) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase2 check() asked to "
"ignore the packet");
return;
}
data->phase2_method->process(sm, data->phase2_priv, in_data, in_len);
if (!data->phase2_method->isDone(sm, data->phase2_priv))
return;
if (!data->phase2_method->isSuccess(sm, data->phase2_priv)) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase2 method failed");
next_type = eap_peap_req_failure(sm, data);
eap_peap_phase2_init(sm, data, next_type);
return;
}
switch (data->state) {
case PHASE2_ID:
if (eap_user_get(sm, sm->identity, sm->identity_len, 1) != 0) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP_PEAP: Phase2 "
"Identity not found in the user "
"database",
sm->identity, sm->identity_len);
next_type = eap_peap_req_failure(sm, data);
break;
}
eap_peap_state(data, PHASE2_METHOD);
next_type = sm->user->methods[0];
sm->user_eap_method_index = 1;
wpa_printf(MSG_DEBUG, "EAP-PEAP: try EAP type %d", next_type);
break;
case PHASE2_METHOD:
next_type = eap_peap_req_success(sm, data);
break;
case PHASE2_TLV:
if (sm->tlv_request == TLV_REQ_SUCCESS ||
data->state == SUCCESS_REQ) {
eap_peap_state(data, SUCCESS);
} else {
eap_peap_state(data, FAILURE);
}
break;
case FAILURE:
break;
default:
wpa_printf(MSG_DEBUG, "EAP-PEAP: %s - unexpected state %d",
__func__, data->state);
break;
}
eap_peap_phase2_init(sm, data, next_type);
}
static void eap_peap_process_phase2(struct eap_sm *sm,
struct eap_peap_data *data,
struct eap_hdr *resp,
u8 *in_data, size_t in_len)
{
u8 *in_decrypted;
int buf_len, len_decrypted, len, res;
struct eap_hdr *hdr;
wpa_printf(MSG_DEBUG, "EAP-PEAP: received %lu bytes encrypted data for"
" Phase 2", (unsigned long) in_len);
res = eap_tls_data_reassemble(sm, &data->ssl, &in_data, &in_len);
if (res < 0 || res == 1)
return;
buf_len = in_len;
if (data->ssl.tls_in_total > buf_len)
buf_len = data->ssl.tls_in_total;
in_decrypted = malloc(buf_len);
if (in_decrypted == NULL) {
free(data->ssl.tls_in);
data->ssl.tls_in = NULL;
data->ssl.tls_in_len = 0;
wpa_printf(MSG_WARNING, "EAP-PEAP: failed to allocate memory "
"for decryption");
return;
}
len_decrypted = tls_connection_decrypt(sm->ssl_ctx, data->ssl.conn,
in_data, in_len,
in_decrypted, buf_len);
free(data->ssl.tls_in);
data->ssl.tls_in = NULL;
data->ssl.tls_in_len = 0;
if (len_decrypted < 0) {
wpa_printf(MSG_INFO, "EAP-PEAP: Failed to decrypt Phase 2 "
"data");
free(in_decrypted);
eap_peap_state(data, FAILURE);
return;
}
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: Decrypted Phase 2 EAP",
in_decrypted, len_decrypted);
hdr = (struct eap_hdr *) in_decrypted;
if (data->peap_version == 0 && data->state != PHASE2_TLV) {
struct eap_hdr *nhdr = malloc(sizeof(struct eap_hdr) +
len_decrypted);
if (nhdr == NULL) {
free(in_decrypted);
return;
}
memcpy((u8 *) (nhdr + 1), in_decrypted, len_decrypted);
free(in_decrypted);
nhdr->code = resp->code;
nhdr->identifier = resp->identifier;
nhdr->length = host_to_be16(sizeof(struct eap_hdr) +
len_decrypted);
len_decrypted += sizeof(struct eap_hdr);
in_decrypted = (u8 *) nhdr;
}
hdr = (struct eap_hdr *) in_decrypted;
if (len_decrypted < sizeof(*hdr)) {
free(in_decrypted);
wpa_printf(MSG_INFO, "EAP-PEAP: Too short Phase 2 "
"EAP frame (len=%d)", len_decrypted);
eap_peap_req_failure(sm, data);
return;
}
len = be_to_host16(hdr->length);
if (len > len_decrypted) {
free(in_decrypted);
wpa_printf(MSG_INFO, "EAP-PEAP: Length mismatch in "
"Phase 2 EAP frame (len=%d hdr->length=%d)",
len_decrypted, len);
eap_peap_req_failure(sm, data);
return;
}
wpa_printf(MSG_DEBUG, "EAP-PEAP: received Phase 2: code=%d "
"identifier=%d length=%d", hdr->code, hdr->identifier, len);
switch (hdr->code) {
case EAP_CODE_RESPONSE:
eap_peap_process_phase2_response(sm, data, (u8 *) hdr, len);
break;
case EAP_CODE_SUCCESS:
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase 2 Success");
if (data->state == SUCCESS_REQ) {
eap_peap_state(data, SUCCESS);
}
break;
case EAP_CODE_FAILURE:
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase 2 Failure");
eap_peap_state(data, FAILURE);
break;
default:
wpa_printf(MSG_INFO, "EAP-PEAP: Unexpected code=%d in "
"Phase 2 EAP header", hdr->code);
break;
}
free(in_decrypted);
}
static void eap_peap_process(struct eap_sm *sm, void *priv,
u8 *respData, size_t respDataLen)
{
struct eap_peap_data *data = priv;
struct eap_hdr *resp;
u8 *pos, flags;
int left;
unsigned int tls_msg_len;
int peer_version;
resp = (struct eap_hdr *) respData;
pos = (u8 *) (resp + 1);
pos++;
flags = *pos++;
left = htons(resp->length) - sizeof(struct eap_hdr) - 2;
wpa_printf(MSG_DEBUG, "EAP-PEAP: Received packet(len=%lu) - "
"Flags 0x%02x", (unsigned long) respDataLen, flags);
peer_version = flags & EAP_PEAP_VERSION_MASK;
if (data->force_version >= 0 && peer_version != data->force_version) {
wpa_printf(MSG_INFO, "EAP-PEAP: peer did not select the forced"
" version (forced=%d peer=%d) - reject",
data->force_version, peer_version);
eap_peap_state(data, FAILURE);
return;
}
if (peer_version < data->peap_version) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: peer ver=%d, own ver=%d; "
"use version %d",
peer_version, data->peap_version, peer_version);
data->peap_version = peer_version;
}
if (flags & EAP_TLS_FLAGS_LENGTH_INCLUDED) {
if (left < 4) {
wpa_printf(MSG_INFO, "EAP-PEAP: Short frame with TLS "
"length");
eap_peap_state(data, FAILURE);
return;
}
tls_msg_len = (pos[0] << 24) | (pos[1] << 16) | (pos[2] << 8) |
pos[3];
wpa_printf(MSG_DEBUG, "EAP-PEAP: TLS Message Length: %d",
tls_msg_len);
if (data->ssl.tls_in_left == 0) {
data->ssl.tls_in_total = tls_msg_len;
data->ssl.tls_in_left = tls_msg_len;
free(data->ssl.tls_in);
data->ssl.tls_in = NULL;
data->ssl.tls_in_len = 0;
}
pos += 4;
left -= 4;
}
switch (data->state) {
case PHASE1:
if (eap_tls_process_helper(sm, &data->ssl, pos, left) < 0) {
wpa_printf(MSG_INFO, "EAP-PEAP: TLS processing "
"failed");
eap_peap_state(data, FAILURE);
}
break;
case PHASE2_START:
eap_peap_state(data, PHASE2_ID);
eap_peap_phase2_init(sm, data, EAP_TYPE_IDENTITY);
break;
case PHASE2_ID:
case PHASE2_METHOD:
case PHASE2_TLV:
eap_peap_process_phase2(sm, data, resp, pos, left);
break;
case SUCCESS_REQ:
eap_peap_state(data, SUCCESS);
break;
case FAILURE_REQ:
eap_peap_state(data, FAILURE);
break;
default:
wpa_printf(MSG_DEBUG, "EAP-PEAP: Unexpected state %d in %s",
data->state, __func__);
break;
}
if (tls_connection_get_write_alerts(sm->ssl_ctx, data->ssl.conn) > 1) {
wpa_printf(MSG_INFO, "EAP-PEAP: Locally detected fatal error "
"in TLS processing");
eap_peap_state(data, FAILURE);
}
}
static Boolean eap_peap_isDone(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
return data->state == SUCCESS || data->state == FAILURE;
}
static u8 * eap_peap_getKey(struct eap_sm *sm, void *priv, size_t *len)
{
struct eap_peap_data *data = priv;
u8 *eapKeyData;
if (data->state != SUCCESS)
return NULL;
/* TODO: PEAPv1 - different label in some cases */
eapKeyData = eap_tls_derive_key(sm, &data->ssl,
"client EAP encryption",
EAP_TLS_KEY_LEN);
if (eapKeyData) {
*len = EAP_TLS_KEY_LEN;
wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Derived key",
eapKeyData, EAP_TLS_KEY_LEN);
} else {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Failed to derive key");
}
return eapKeyData;
}
static Boolean eap_peap_isSuccess(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
return data->state == SUCCESS;
}
const struct eap_method eap_method_peap =
{
.method = EAP_TYPE_PEAP,
.name = "PEAP",
.init = eap_peap_init,
.reset = eap_peap_reset,
.buildReq = eap_peap_buildReq,
.check = eap_peap_check,
.process = eap_peap_process,
.isDone = eap_peap_isDone,
.getKey = eap_peap_getKey,
.isSuccess = eap_peap_isSuccess,
};