fragattacks/src/eap_peer/eap_peap.c

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/*
* EAP peer method: EAP-PEAP (draft-josefsson-pppext-eap-tls-eap-10.txt)
* Copyright (c) 2004-2008, Jouni Malinen <j@w1.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 "includes.h"
#include "common.h"
#include "crypto/sha1.h"
#include "eap_i.h"
#include "eap_tls_common.h"
#include "eap_config.h"
#include "tls.h"
#include "eap_common/eap_tlv_common.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-10.txt
*/
#define EAP_PEAP_VERSION 1
static void eap_peap_deinit(struct eap_sm *sm, void *priv);
struct eap_peap_data {
struct eap_ssl_data ssl;
int peap_version, force_peap_version, force_new_label;
const struct eap_method *phase2_method;
void *phase2_priv;
int phase2_success;
int phase2_eap_success;
int phase2_eap_started;
struct eap_method_type phase2_type;
struct eap_method_type *phase2_types;
size_t num_phase2_types;
int peap_outer_success; /* 0 = PEAP terminated on Phase 2 inner
* EAP-Success
* 1 = reply with tunneled EAP-Success to inner
* EAP-Success and expect AS to send outer
* (unencrypted) EAP-Success after this
* 2 = reply with PEAP/TLS ACK to inner
* EAP-Success and expect AS to send outer
* (unencrypted) EAP-Success after this */
int resuming; /* starting a resumed session */
u8 *key_data;
struct wpabuf *pending_phase2_req;
enum { NO_BINDING, OPTIONAL_BINDING, REQUIRE_BINDING } crypto_binding;
int crypto_binding_used;
u8 ipmk[40];
u8 cmk[20];
};
static int eap_peap_parse_phase1(struct eap_peap_data *data,
const char *phase1)
{
const char *pos;
pos = os_strstr(phase1, "peapver=");
if (pos) {
data->force_peap_version = atoi(pos + 8);
data->peap_version = data->force_peap_version;
wpa_printf(MSG_DEBUG, "EAP-PEAP: Forced PEAP version %d",
data->force_peap_version);
}
if (os_strstr(phase1, "peaplabel=1")) {
data->force_new_label = 1;
wpa_printf(MSG_DEBUG, "EAP-PEAP: Force new label for key "
"derivation");
}
if (os_strstr(phase1, "peap_outer_success=0")) {
data->peap_outer_success = 0;
wpa_printf(MSG_DEBUG, "EAP-PEAP: terminate authentication on "
"tunneled EAP-Success");
} else if (os_strstr(phase1, "peap_outer_success=1")) {
data->peap_outer_success = 1;
wpa_printf(MSG_DEBUG, "EAP-PEAP: send tunneled EAP-Success "
"after receiving tunneled EAP-Success");
} else if (os_strstr(phase1, "peap_outer_success=2")) {
data->peap_outer_success = 2;
wpa_printf(MSG_DEBUG, "EAP-PEAP: send PEAP/TLS ACK after "
"receiving tunneled EAP-Success");
}
return 0;
}
static void * eap_peap_init(struct eap_sm *sm)
{
struct eap_peap_data *data;
struct eap_peer_config *config = eap_get_config(sm);
data = os_zalloc(sizeof(*data));
if (data == NULL)
return NULL;
sm->peap_done = FALSE;
data->peap_version = EAP_PEAP_VERSION;
data->force_peap_version = -1;
data->peap_outer_success = 2;
data->crypto_binding = NO_BINDING;
if (config && config->phase1 &&
eap_peap_parse_phase1(data, config->phase1) < 0) {
eap_peap_deinit(sm, data);
return NULL;
}
if (eap_peer_select_phase2_methods(config, "auth=",
&data->phase2_types,
&data->num_phase2_types) < 0) {
eap_peap_deinit(sm, data);
return NULL;
}
data->phase2_type.vendor = EAP_VENDOR_IETF;
data->phase2_type.method = EAP_TYPE_NONE;
if (eap_peer_tls_ssl_init(sm, &data->ssl, config)) {
wpa_printf(MSG_INFO, "EAP-PEAP: Failed to initialize SSL.");
eap_peap_deinit(sm, data);
return NULL;
}
return data;
}
static void eap_peap_deinit(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->deinit(sm, data->phase2_priv);
os_free(data->phase2_types);
eap_peer_tls_ssl_deinit(sm, &data->ssl);
os_free(data->key_data);
wpabuf_free(data->pending_phase2_req);
os_free(data);
}
/**
* eap_tlv_build_nak - Build EAP-TLV NAK message
* @id: EAP identifier for the header
* @nak_type: TLV type (EAP_TLV_*)
* Returns: Buffer to the allocated EAP-TLV NAK message or %NULL on failure
*
* This funtion builds an EAP-TLV NAK message. The caller is responsible for
* freeing the returned buffer.
*/
static struct wpabuf * eap_tlv_build_nak(int id, u16 nak_type)
{
struct wpabuf *msg;
msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TLV, 10,
EAP_CODE_RESPONSE, id);
if (msg == NULL)
return NULL;
wpabuf_put_u8(msg, 0x80); /* Mandatory */
wpabuf_put_u8(msg, EAP_TLV_NAK_TLV);
wpabuf_put_be16(msg, 6); /* Length */
wpabuf_put_be32(msg, 0); /* Vendor-Id */
wpabuf_put_be16(msg, nak_type); /* NAK-Type */
return msg;
}
static int eap_peap_get_isk(struct eap_sm *sm, struct eap_peap_data *data,
u8 *isk, size_t isk_len)
{
u8 *key;
size_t key_len;
os_memset(isk, 0, isk_len);
if (data->phase2_method == NULL || data->phase2_priv == NULL ||
data->phase2_method->isKeyAvailable == NULL ||
data->phase2_method->getKey == NULL)
return 0;
if (!data->phase2_method->isKeyAvailable(sm, data->phase2_priv) ||
(key = data->phase2_method->getKey(sm, data->phase2_priv,
&key_len)) == NULL) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Could not get key material "
"from Phase 2");
return -1;
}
if (key_len == 32 &&
data->phase2_method->vendor == EAP_VENDOR_IETF &&
data->phase2_method->method == EAP_TYPE_MSCHAPV2) {
/*
* Microsoft uses reverse order for MS-MPPE keys in
* EAP-PEAP when compared to EAP-FAST derivation of
* ISK. Swap the keys here to get the correct ISK for
* EAP-PEAPv0 cryptobinding.
*/
u8 tmp[16];
os_memcpy(tmp, key, 16);
os_memcpy(key, key + 16, 16);
os_memcpy(key + 16, tmp, 16);
}
if (key_len > isk_len)
key_len = isk_len;
os_memcpy(isk, key, key_len);
os_free(key);
return 0;
}
void peap_prfplus(int version, const u8 *key, size_t key_len,
const char *label, const u8 *seed, size_t seed_len,
u8 *buf, size_t buf_len)
{
unsigned char counter = 0;
size_t pos, plen;
u8 hash[SHA1_MAC_LEN];
size_t label_len = os_strlen(label);
u8 extra[2];
const unsigned char *addr[5];
size_t len[5];
addr[0] = hash;
len[0] = 0;
addr[1] = (unsigned char *) label;
len[1] = label_len;
addr[2] = seed;
len[2] = seed_len;
if (version == 0) {
/*
* PRF+(K, S, LEN) = T1 | T2 | ... | Tn
* T1 = HMAC-SHA1(K, S | 0x01 | 0x00 | 0x00)
* T2 = HMAC-SHA1(K, T1 | S | 0x02 | 0x00 | 0x00)
* ...
* Tn = HMAC-SHA1(K, Tn-1 | S | n | 0x00 | 0x00)
*/
extra[0] = 0;
extra[1] = 0;
addr[3] = &counter;
len[3] = 1;
addr[4] = extra;
len[4] = 2;
} else {
/*
* PRF (K,S,LEN) = T1 | T2 | T3 | T4 | ... where:
* T1 = HMAC-SHA1(K, S | LEN | 0x01)
* T2 = HMAC-SHA1 (K, T1 | S | LEN | 0x02)
* T3 = HMAC-SHA1 (K, T2 | S | LEN | 0x03)
* T4 = HMAC-SHA1 (K, T3 | S | LEN | 0x04)
* ...
*/
extra[0] = buf_len & 0xff;
addr[3] = extra;
len[3] = 1;
addr[4] = &counter;
len[4] = 1;
}
pos = 0;
while (pos < buf_len) {
counter++;
plen = buf_len - pos;
hmac_sha1_vector(key, key_len, 5, addr, len, hash);
if (plen >= SHA1_MAC_LEN) {
os_memcpy(&buf[pos], hash, SHA1_MAC_LEN);
pos += SHA1_MAC_LEN;
} else {
os_memcpy(&buf[pos], hash, plen);
break;
}
len[0] = SHA1_MAC_LEN;
}
}
static int eap_peap_derive_cmk(struct eap_sm *sm, struct eap_peap_data *data)
{
u8 *tk;
u8 isk[32], imck[60];
/*
* Tunnel key (TK) is the first 60 octets of the key generated by
* phase 1 of PEAP (based on TLS).
*/
tk = data->key_data;
if (tk == NULL)
return -1;
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: TK", tk, 60);
if (eap_peap_get_isk(sm, data, isk, sizeof(isk)) < 0)
return -1;
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: ISK", isk, sizeof(isk));
/*
* IPMK Seed = "Inner Methods Compound Keys" | ISK
* TempKey = First 40 octets of TK
* IPMK|CMK = PRF+(TempKey, IPMK Seed, 60)
* (note: draft-josefsson-pppext-eap-tls-eap-10.txt includes a space
* in the end of the label just before ISK; is that just a typo?)
*/
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: TempKey", tk, 40);
peap_prfplus(data->peap_version, tk, 40, "Inner Methods Compound Keys",
isk, sizeof(isk), imck, sizeof(imck));
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: IMCK (IPMKj)",
imck, sizeof(imck));
/* TODO: fast-connect: IPMK|CMK = TK */
os_memcpy(data->ipmk, imck, 40);
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: IPMK (S-IPMKj)", data->ipmk, 40);
os_memcpy(data->cmk, imck + 40, 20);
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: CMK (CMKj)", data->cmk, 20);
return 0;
}
static int eap_tlv_add_cryptobinding(struct eap_sm *sm,
struct eap_peap_data *data,
struct wpabuf *buf)
{
u8 *mac;
u8 eap_type = EAP_TYPE_PEAP;
const u8 *addr[2];
size_t len[2];
u16 tlv_type;
u8 binding_nonce[32];
/* FIX: should binding_nonce be copied from request? */
if (os_get_random(binding_nonce, 32))
return -1;
/* Compound_MAC: HMAC-SHA1-160(cryptobinding TLV | EAP type) */
addr[0] = wpabuf_put(buf, 0);
len[0] = 60;
addr[1] = &eap_type;
len[1] = 1;
tlv_type = EAP_TLV_CRYPTO_BINDING_TLV;
if (data->peap_version >= 2)
tlv_type |= EAP_TLV_TYPE_MANDATORY;
wpabuf_put_be16(buf, tlv_type);
wpabuf_put_be16(buf, 56);
wpabuf_put_u8(buf, 0); /* Reserved */
wpabuf_put_u8(buf, data->peap_version); /* Version */
wpabuf_put_u8(buf, data->peap_version); /* RecvVersion */
wpabuf_put_u8(buf, 1); /* SubType: 0 = Request, 1 = Response */
wpabuf_put_data(buf, binding_nonce, 32); /* Nonce */
mac = wpabuf_put(buf, 20); /* Compound_MAC */
wpa_hexdump(MSG_MSGDUMP, "EAP-PEAP: Compound_MAC CMK", data->cmk, 20);
wpa_hexdump(MSG_MSGDUMP, "EAP-PEAP: Compound_MAC data 1",
addr[0], len[0]);
wpa_hexdump(MSG_MSGDUMP, "EAP-PEAP: Compound_MAC data 2",
addr[1], len[1]);
hmac_sha1_vector(data->cmk, 20, 2, addr, len, mac);
wpa_hexdump(MSG_MSGDUMP, "EAP-PEAP: Compound_MAC", mac, SHA1_MAC_LEN);
data->crypto_binding_used = 1;
return 0;
}
/**
* eap_tlv_build_result - Build EAP-TLV Result message
* @id: EAP identifier for the header
* @status: Status (EAP_TLV_RESULT_SUCCESS or EAP_TLV_RESULT_FAILURE)
* Returns: Buffer to the allocated EAP-TLV Result message or %NULL on failure
*
* This funtion builds an EAP-TLV Result message. The caller is responsible for
* freeing the returned buffer.
*/
static struct wpabuf * eap_tlv_build_result(struct eap_sm *sm,
struct eap_peap_data *data,
int crypto_tlv_used,
int id, u16 status)
{
struct wpabuf *msg;
size_t len;
if (data->crypto_binding == NO_BINDING)
crypto_tlv_used = 0;
len = 6;
if (crypto_tlv_used)
len += 60; /* Cryptobinding TLV */
msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TLV, len,
EAP_CODE_RESPONSE, id);
if (msg == NULL)
return NULL;
wpabuf_put_u8(msg, 0x80); /* Mandatory */
wpabuf_put_u8(msg, EAP_TLV_RESULT_TLV);
wpabuf_put_be16(msg, 2); /* Length */
wpabuf_put_be16(msg, status); /* Status */
if (crypto_tlv_used && eap_tlv_add_cryptobinding(sm, data, msg)) {
wpabuf_free(msg);
return NULL;
}
return msg;
}
static int eap_tlv_validate_cryptobinding(struct eap_sm *sm,
struct eap_peap_data *data,
const u8 *crypto_tlv,
size_t crypto_tlv_len)
{
u8 buf[61], mac[SHA1_MAC_LEN];
const u8 *pos;
if (eap_peap_derive_cmk(sm, data) < 0) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Could not derive CMK");
return -1;
}
if (crypto_tlv_len != 4 + 56) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Invalid cryptobinding TLV "
"length %d", (int) crypto_tlv_len);
return -1;
}
pos = crypto_tlv;
pos += 4; /* TLV header */
if (pos[1] != data->peap_version) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Cryptobinding TLV Version "
"mismatch (was %d; expected %d)",
pos[1], data->peap_version);
return -1;
}
if (pos[3] != 0) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Unexpected Cryptobinding TLV "
"SubType %d", pos[3]);
return -1;
}
pos += 4;
pos += 32; /* Nonce */
/* Compound_MAC: HMAC-SHA1-160(cryptobinding TLV | EAP type) */
os_memcpy(buf, crypto_tlv, 60);
os_memset(buf + 4 + 4 + 32, 0, 20); /* Compound_MAC */
buf[60] = EAP_TYPE_PEAP;
hmac_sha1(data->cmk, 20, buf, sizeof(buf), mac);
if (os_memcmp(mac, pos, SHA1_MAC_LEN) != 0) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Invalid Compound_MAC in "
"cryptobinding TLV");
return -1;
}
wpa_printf(MSG_DEBUG, "EAP-PEAP: Valid cryptobinding TLV received");
return 0;
}
/**
* eap_tlv_process - Process a received EAP-TLV message and generate a response
* @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
* @ret: Return values from EAP request validation and processing
* @req: EAP-TLV request to be processed. The caller must have validated that
* the buffer is large enough to contain full request (hdr->length bytes) and
* that the EAP type is EAP_TYPE_TLV.
* @resp: Buffer to return a pointer to the allocated response message. This
* field should be initialized to %NULL before the call. The value will be
* updated if a response message is generated. The caller is responsible for
* freeing the allocated message.
* @force_failure: Force negotiation to fail
* Returns: 0 on success, -1 on failure
*/
static int eap_tlv_process(struct eap_sm *sm, struct eap_peap_data *data,
struct eap_method_ret *ret,
const struct wpabuf *req, struct wpabuf **resp,
int force_failure)
{
size_t left, tlv_len;
const u8 *pos;
const u8 *result_tlv = NULL, *crypto_tlv = NULL;
size_t result_tlv_len = 0, crypto_tlv_len = 0;
int tlv_type, mandatory;
/* Parse TLVs */
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_TLV, req, &left);
if (pos == NULL)
return -1;
wpa_hexdump(MSG_DEBUG, "EAP-TLV: Received TLVs", pos, left);
while (left >= 4) {
mandatory = !!(pos[0] & 0x80);
tlv_type = WPA_GET_BE16(pos) & 0x3fff;
pos += 2;
tlv_len = WPA_GET_BE16(pos);
pos += 2;
left -= 4;
if (tlv_len > left) {
wpa_printf(MSG_DEBUG, "EAP-TLV: TLV underrun "
"(tlv_len=%lu left=%lu)",
(unsigned long) tlv_len,
(unsigned long) left);
return -1;
}
switch (tlv_type) {
case EAP_TLV_RESULT_TLV:
result_tlv = pos;
result_tlv_len = tlv_len;
break;
case EAP_TLV_CRYPTO_BINDING_TLV:
crypto_tlv = pos;
crypto_tlv_len = tlv_len;
break;
default:
wpa_printf(MSG_DEBUG, "EAP-TLV: Unsupported TLV Type "
"%d%s", tlv_type,
mandatory ? " (mandatory)" : "");
if (mandatory) {
/* NAK TLV and ignore all TLVs in this packet.
*/
*resp = eap_tlv_build_nak(eap_get_id(req),
tlv_type);
return *resp == NULL ? -1 : 0;
}
/* Ignore this TLV, but process other TLVs */
break;
}
pos += tlv_len;
left -= tlv_len;
}
if (left) {
wpa_printf(MSG_DEBUG, "EAP-TLV: Last TLV too short in "
"Request (left=%lu)", (unsigned long) left);
return -1;
}
/* Process supported TLVs */
if (crypto_tlv && data->crypto_binding != NO_BINDING) {
wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Cryptobinding TLV",
crypto_tlv, crypto_tlv_len);
if (eap_tlv_validate_cryptobinding(sm, data, crypto_tlv - 4,
crypto_tlv_len + 4) < 0) {
if (result_tlv == NULL)
return -1;
force_failure = 1;
}
} else if (!crypto_tlv && data->crypto_binding == REQUIRE_BINDING) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: No cryptobinding TLV");
return -1;
}
if (result_tlv) {
int status, resp_status;
wpa_hexdump(MSG_DEBUG, "EAP-TLV: Result TLV",
result_tlv, result_tlv_len);
if (result_tlv_len < 2) {
wpa_printf(MSG_INFO, "EAP-TLV: Too short Result TLV "
"(len=%lu)",
(unsigned long) result_tlv_len);
return -1;
}
status = WPA_GET_BE16(result_tlv);
if (status == EAP_TLV_RESULT_SUCCESS) {
wpa_printf(MSG_INFO, "EAP-TLV: TLV Result - Success "
"- EAP-TLV/Phase2 Completed");
if (force_failure) {
wpa_printf(MSG_INFO, "EAP-TLV: Earlier failure"
" - force failed Phase 2");
resp_status = EAP_TLV_RESULT_FAILURE;
ret->decision = DECISION_FAIL;
} else {
resp_status = EAP_TLV_RESULT_SUCCESS;
ret->decision = DECISION_UNCOND_SUCC;
}
} else if (status == EAP_TLV_RESULT_FAILURE) {
wpa_printf(MSG_INFO, "EAP-TLV: TLV Result - Failure");
resp_status = EAP_TLV_RESULT_FAILURE;
ret->decision = DECISION_FAIL;
} else {
wpa_printf(MSG_INFO, "EAP-TLV: Unknown TLV Result "
"Status %d", status);
resp_status = EAP_TLV_RESULT_FAILURE;
ret->decision = DECISION_FAIL;
}
ret->methodState = METHOD_DONE;
*resp = eap_tlv_build_result(sm, data, crypto_tlv != NULL,
eap_get_id(req), resp_status);
}
return 0;
}
static struct wpabuf * eap_peapv2_tlv_eap_payload(struct wpabuf *buf)
{
struct wpabuf *e;
struct eap_tlv_hdr *tlv;
if (buf == NULL)
return NULL;
/* Encapsulate EAP packet in EAP-Payload TLV */
wpa_printf(MSG_DEBUG, "EAP-PEAPv2: Add EAP-Payload TLV");
e = wpabuf_alloc(sizeof(*tlv) + wpabuf_len(buf));
if (e == NULL) {
wpa_printf(MSG_DEBUG, "EAP-PEAPv2: Failed to allocate memory "
"for TLV encapsulation");
wpabuf_free(buf);
return NULL;
}
tlv = wpabuf_put(e, sizeof(*tlv));
tlv->tlv_type = host_to_be16(EAP_TLV_TYPE_MANDATORY |
EAP_TLV_EAP_PAYLOAD_TLV);
tlv->length = host_to_be16(wpabuf_len(buf));
wpabuf_put_buf(e, buf);
wpabuf_free(buf);
return e;
}
static int eap_peap_phase2_request(struct eap_sm *sm,
struct eap_peap_data *data,
struct eap_method_ret *ret,
struct wpabuf *req,
struct wpabuf **resp)
{
struct eap_hdr *hdr = wpabuf_mhead(req);
size_t len = be_to_host16(hdr->length);
u8 *pos;
struct eap_method_ret iret;
struct eap_peer_config *config = eap_get_config(sm);
if (len <= sizeof(struct eap_hdr)) {
wpa_printf(MSG_INFO, "EAP-PEAP: too short "
"Phase 2 request (len=%lu)", (unsigned long) len);
return -1;
}
pos = (u8 *) (hdr + 1);
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase 2 Request: type=%d", *pos);
switch (*pos) {
case EAP_TYPE_IDENTITY:
*resp = eap_sm_buildIdentity(sm, hdr->identifier, 1);
break;
case EAP_TYPE_TLV:
os_memset(&iret, 0, sizeof(iret));
if (eap_tlv_process(sm, data, &iret, req, resp,
data->phase2_eap_started &&
!data->phase2_eap_success)) {
ret->methodState = METHOD_DONE;
ret->decision = DECISION_FAIL;
return -1;
}
if (iret.methodState == METHOD_DONE ||
iret.methodState == METHOD_MAY_CONT) {
ret->methodState = iret.methodState;
ret->decision = iret.decision;
data->phase2_success = 1;
}
break;
default:
if (data->phase2_type.vendor == EAP_VENDOR_IETF &&
data->phase2_type.method == EAP_TYPE_NONE) {
size_t i;
for (i = 0; i < data->num_phase2_types; i++) {
if (data->phase2_types[i].vendor !=
EAP_VENDOR_IETF ||
data->phase2_types[i].method != *pos)
continue;
data->phase2_type.vendor =
data->phase2_types[i].vendor;
data->phase2_type.method =
data->phase2_types[i].method;
wpa_printf(MSG_DEBUG, "EAP-PEAP: Selected "
"Phase 2 EAP vendor %d method %d",
data->phase2_type.vendor,
data->phase2_type.method);
break;
}
}
if (*pos != data->phase2_type.method ||
*pos == EAP_TYPE_NONE) {
if (eap_peer_tls_phase2_nak(data->phase2_types,
data->num_phase2_types,
hdr, resp))
return -1;
return 0;
}
if (data->phase2_priv == NULL) {
data->phase2_method = eap_peer_get_eap_method(
data->phase2_type.vendor,
data->phase2_type.method);
if (data->phase2_method) {
sm->init_phase2 = 1;
sm->mschapv2_full_key = 1;
data->phase2_priv =
data->phase2_method->init(sm);
sm->init_phase2 = 0;
sm->mschapv2_full_key = 0;
}
}
if (data->phase2_priv == NULL || data->phase2_method == NULL) {
wpa_printf(MSG_INFO, "EAP-PEAP: failed to initialize "
"Phase 2 EAP method %d", *pos);
ret->methodState = METHOD_DONE;
ret->decision = DECISION_FAIL;
return -1;
}
data->phase2_eap_started = 1;
os_memset(&iret, 0, sizeof(iret));
*resp = data->phase2_method->process(sm, data->phase2_priv,
&iret, req);
if ((iret.methodState == METHOD_DONE ||
iret.methodState == METHOD_MAY_CONT) &&
(iret.decision == DECISION_UNCOND_SUCC ||
iret.decision == DECISION_COND_SUCC)) {
data->phase2_eap_success = 1;
data->phase2_success = 1;
}
break;
}
if (*resp == NULL &&
(config->pending_req_identity || config->pending_req_password ||
config->pending_req_otp || config->pending_req_new_password)) {
wpabuf_free(data->pending_phase2_req);
data->pending_phase2_req = wpabuf_alloc_copy(hdr, len);
}
return 0;
}
static int eap_peap_decrypt(struct eap_sm *sm, struct eap_peap_data *data,
struct eap_method_ret *ret,
const struct eap_hdr *req,
const struct wpabuf *in_data,
struct wpabuf **out_data)
{
struct wpabuf *in_decrypted = NULL;
int res, skip_change = 0;
struct eap_hdr *hdr, *rhdr;
struct wpabuf *resp = NULL;
size_t len;
wpa_printf(MSG_DEBUG, "EAP-PEAP: received %lu bytes encrypted data for"
" Phase 2", (unsigned long) wpabuf_len(in_data));
if (data->pending_phase2_req) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Pending Phase 2 request - "
"skip decryption and use old data");
/* Clear TLS reassembly state. */
eap_peer_tls_reset_input(&data->ssl);
in_decrypted = data->pending_phase2_req;
data->pending_phase2_req = NULL;
skip_change = 1;
goto continue_req;
}
if (wpabuf_len(in_data) == 0 && sm->workaround &&
data->phase2_success) {
/*
* Cisco ACS seems to be using TLS ACK to terminate
* EAP-PEAPv0/GTC. Try to reply with TLS ACK.
*/
wpa_printf(MSG_DEBUG, "EAP-PEAP: Received TLS ACK, but "
"expected data - acknowledge with TLS ACK since "
"Phase 2 has been completed");
ret->decision = DECISION_COND_SUCC;
ret->methodState = METHOD_DONE;
return 1;
} else if (wpabuf_len(in_data) == 0) {
/* Received TLS ACK - requesting more fragments */
return eap_peer_tls_encrypt(sm, &data->ssl, EAP_TYPE_PEAP,
data->peap_version,
req->identifier, NULL, out_data);
}
res = eap_peer_tls_decrypt(sm, &data->ssl, in_data, &in_decrypted);
if (res)
return res;
continue_req:
wpa_hexdump_buf(MSG_DEBUG, "EAP-PEAP: Decrypted Phase 2 EAP",
in_decrypted);
hdr = wpabuf_mhead(in_decrypted);
if (wpabuf_len(in_decrypted) == 5 && hdr->code == EAP_CODE_REQUEST &&
be_to_host16(hdr->length) == 5 &&
eap_get_type(in_decrypted) == EAP_TYPE_IDENTITY) {
/* At least FreeRADIUS seems to send full EAP header with
* EAP Request Identity */
skip_change = 1;
}
if (wpabuf_len(in_decrypted) >= 5 && hdr->code == EAP_CODE_REQUEST &&
eap_get_type(in_decrypted) == EAP_TYPE_TLV) {
skip_change = 1;
}
if (data->peap_version == 0 && !skip_change) {
struct eap_hdr *nhdr;
struct wpabuf *nmsg = wpabuf_alloc(sizeof(struct eap_hdr) +
wpabuf_len(in_decrypted));
if (nmsg == NULL) {
wpabuf_free(in_decrypted);
return 0;
}
nhdr = wpabuf_put(nmsg, sizeof(*nhdr));
wpabuf_put_buf(nmsg, in_decrypted);
nhdr->code = req->code;
nhdr->identifier = req->identifier;
nhdr->length = host_to_be16(sizeof(struct eap_hdr) +
wpabuf_len(in_decrypted));
wpabuf_free(in_decrypted);
in_decrypted = nmsg;
}
if (data->peap_version >= 2) {
struct eap_tlv_hdr *tlv;
struct wpabuf *nmsg;
if (wpabuf_len(in_decrypted) < sizeof(*tlv) + sizeof(*hdr)) {
wpa_printf(MSG_INFO, "EAP-PEAPv2: Too short Phase 2 "
"EAP TLV");
wpabuf_free(in_decrypted);
return 0;
}
tlv = wpabuf_mhead(in_decrypted);
if ((be_to_host16(tlv->tlv_type) & 0x3fff) !=
EAP_TLV_EAP_PAYLOAD_TLV) {
wpa_printf(MSG_INFO, "EAP-PEAPv2: Not an EAP TLV");
wpabuf_free(in_decrypted);
return 0;
}
if (sizeof(*tlv) + be_to_host16(tlv->length) >
wpabuf_len(in_decrypted)) {
wpa_printf(MSG_INFO, "EAP-PEAPv2: Invalid EAP TLV "
"length");
wpabuf_free(in_decrypted);
return 0;
}
hdr = (struct eap_hdr *) (tlv + 1);
if (be_to_host16(hdr->length) > be_to_host16(tlv->length)) {
wpa_printf(MSG_INFO, "EAP-PEAPv2: No room for full "
"EAP packet in EAP TLV");
wpabuf_free(in_decrypted);
return 0;
}
nmsg = wpabuf_alloc(be_to_host16(hdr->length));
if (nmsg == NULL) {
wpabuf_free(in_decrypted);
return 0;
}
wpabuf_put_data(nmsg, hdr, be_to_host16(hdr->length));
wpabuf_free(in_decrypted);
in_decrypted = nmsg;
}
hdr = wpabuf_mhead(in_decrypted);
if (wpabuf_len(in_decrypted) < sizeof(*hdr)) {
wpa_printf(MSG_INFO, "EAP-PEAP: Too short Phase 2 "
"EAP frame (len=%lu)",
(unsigned long) wpabuf_len(in_decrypted));
wpabuf_free(in_decrypted);
return 0;
}
len = be_to_host16(hdr->length);
if (len > wpabuf_len(in_decrypted)) {
wpa_printf(MSG_INFO, "EAP-PEAP: Length mismatch in "
"Phase 2 EAP frame (len=%lu hdr->length=%lu)",
(unsigned long) wpabuf_len(in_decrypted),
(unsigned long) len);
wpabuf_free(in_decrypted);
return 0;
}
if (len < wpabuf_len(in_decrypted)) {
wpa_printf(MSG_INFO, "EAP-PEAP: Odd.. Phase 2 EAP header has "
"shorter length than full decrypted data "
"(%lu < %lu)",
(unsigned long) len,
(unsigned long) wpabuf_len(in_decrypted));
}
wpa_printf(MSG_DEBUG, "EAP-PEAP: received Phase 2: code=%d "
"identifier=%d length=%lu", hdr->code, hdr->identifier,
(unsigned long) len);
switch (hdr->code) {
case EAP_CODE_REQUEST:
if (eap_peap_phase2_request(sm, data, ret, in_decrypted,
&resp)) {
wpabuf_free(in_decrypted);
wpa_printf(MSG_INFO, "EAP-PEAP: Phase2 Request "
"processing failed");
return 0;
}
break;
case EAP_CODE_SUCCESS:
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase 2 Success");
if (data->peap_version == 1) {
/* EAP-Success within TLS tunnel is used to indicate
* shutdown of the TLS channel. The authentication has
* been completed. */
if (data->phase2_eap_started &&
!data->phase2_eap_success) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase 2 "
"Success used to indicate success, "
"but Phase 2 EAP was not yet "
"completed successfully");
ret->methodState = METHOD_DONE;
ret->decision = DECISION_FAIL;
wpabuf_free(in_decrypted);
return 0;
}
wpa_printf(MSG_DEBUG, "EAP-PEAP: Version 1 - "
"EAP-Success within TLS tunnel - "
"authentication completed");
ret->decision = DECISION_UNCOND_SUCC;
ret->methodState = METHOD_DONE;
data->phase2_success = 1;
if (data->peap_outer_success == 2) {
wpabuf_free(in_decrypted);
wpa_printf(MSG_DEBUG, "EAP-PEAP: Use TLS ACK "
"to finish authentication");
return 1;
} else if (data->peap_outer_success == 1) {
/* Reply with EAP-Success within the TLS
* channel to complete the authentication. */
resp = wpabuf_alloc(sizeof(struct eap_hdr));
if (resp) {
rhdr = wpabuf_put(resp, sizeof(*rhdr));
rhdr->code = EAP_CODE_SUCCESS;
rhdr->identifier = hdr->identifier;
rhdr->length =
host_to_be16(sizeof(*rhdr));
}
} else {
/* No EAP-Success expected for Phase 1 (outer,
* unencrypted auth), so force EAP state
* machine to SUCCESS state. */
sm->peap_done = TRUE;
}
} else {
/* FIX: ? */
}
break;
case EAP_CODE_FAILURE:
wpa_printf(MSG_DEBUG, "EAP-PEAP: Phase 2 Failure");
ret->decision = DECISION_FAIL;
ret->methodState = METHOD_MAY_CONT;
ret->allowNotifications = FALSE;
/* Reply with EAP-Failure within the TLS channel to complete
* failure reporting. */
resp = wpabuf_alloc(sizeof(struct eap_hdr));
if (resp) {
rhdr = wpabuf_put(resp, sizeof(*rhdr));
rhdr->code = EAP_CODE_FAILURE;
rhdr->identifier = hdr->identifier;
rhdr->length = host_to_be16(sizeof(*rhdr));
}
break;
default:
wpa_printf(MSG_INFO, "EAP-PEAP: Unexpected code=%d in "
"Phase 2 EAP header", hdr->code);
break;
}
wpabuf_free(in_decrypted);
if (resp) {
int skip_change2 = 0;
struct wpabuf *rmsg, buf;
wpa_hexdump_buf_key(MSG_DEBUG,
"EAP-PEAP: Encrypting Phase 2 data", resp);
/* PEAP version changes */
if (data->peap_version >= 2) {
resp = eap_peapv2_tlv_eap_payload(resp);
if (resp == NULL)
return -1;
}
if (wpabuf_len(resp) >= 5 &&
wpabuf_head_u8(resp)[0] == EAP_CODE_RESPONSE &&
eap_get_type(resp) == EAP_TYPE_TLV)
skip_change2 = 1;
rmsg = resp;
if (data->peap_version == 0 && !skip_change2) {
wpabuf_set(&buf, wpabuf_head_u8(resp) +
sizeof(struct eap_hdr),
wpabuf_len(resp) - sizeof(struct eap_hdr));
rmsg = &buf;
}
if (eap_peer_tls_encrypt(sm, &data->ssl, EAP_TYPE_PEAP,
data->peap_version, req->identifier,
rmsg, out_data)) {
wpa_printf(MSG_INFO, "EAP-PEAP: Failed to encrypt "
"a Phase 2 frame");
}
wpabuf_free(resp);
}
return 0;
}
static struct wpabuf * eap_peap_process(struct eap_sm *sm, void *priv,
struct eap_method_ret *ret,
const struct wpabuf *reqData)
{
const struct eap_hdr *req;
size_t left;
int res;
u8 flags, id;
struct wpabuf *resp;
const u8 *pos;
struct eap_peap_data *data = priv;
pos = eap_peer_tls_process_init(sm, &data->ssl, EAP_TYPE_PEAP, ret,
reqData, &left, &flags);
if (pos == NULL)
return NULL;
req = wpabuf_head(reqData);
id = req->identifier;
if (flags & EAP_TLS_FLAGS_START) {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Start (server ver=%d, own "
"ver=%d)", flags & EAP_PEAP_VERSION_MASK,
data->peap_version);
if ((flags & EAP_PEAP_VERSION_MASK) < data->peap_version)
data->peap_version = flags & EAP_PEAP_VERSION_MASK;
if (data->force_peap_version >= 0 &&
data->force_peap_version != data->peap_version) {
wpa_printf(MSG_WARNING, "EAP-PEAP: Failed to select "
"forced PEAP version %d",
data->force_peap_version);
ret->methodState = METHOD_DONE;
ret->decision = DECISION_FAIL;
ret->allowNotifications = FALSE;
return NULL;
}
wpa_printf(MSG_DEBUG, "EAP-PEAP: Using PEAP version %d",
data->peap_version);
left = 0; /* make sure that this frame is empty, even though it
* should always be, anyway */
}
resp = NULL;
if (tls_connection_established(sm->ssl_ctx, data->ssl.conn) &&
!data->resuming) {
struct wpabuf msg;
wpabuf_set(&msg, pos, left);
res = eap_peap_decrypt(sm, data, ret, req, &msg, &resp);
} else {
res = eap_peer_tls_process_helper(sm, &data->ssl,
EAP_TYPE_PEAP,
data->peap_version, id, pos,
left, &resp);
if (tls_connection_established(sm->ssl_ctx, data->ssl.conn)) {
char *label;
wpa_printf(MSG_DEBUG,
"EAP-PEAP: TLS done, proceed to Phase 2");
os_free(data->key_data);
/* draft-josefsson-ppext-eap-tls-eap-05.txt
* specifies that PEAPv1 would use "client PEAP
* encryption" as the label. However, most existing
* PEAPv1 implementations seem to be using the old
* label, "client EAP encryption", instead. Use the old
* label by default, but allow it to be configured with
* phase1 parameter peaplabel=1. */
if (data->peap_version > 1 || data->force_new_label)
label = "client PEAP encryption";
else
label = "client EAP encryption";
wpa_printf(MSG_DEBUG, "EAP-PEAP: using label '%s' in "
"key derivation", label);
data->key_data =
eap_peer_tls_derive_key(sm, &data->ssl, label,
EAP_TLS_KEY_LEN);
if (data->key_data) {
wpa_hexdump_key(MSG_DEBUG,
"EAP-PEAP: Derived key",
data->key_data,
EAP_TLS_KEY_LEN);
} else {
wpa_printf(MSG_DEBUG, "EAP-PEAP: Failed to "
"derive key");
}
if (sm->workaround && data->resuming) {
/*
* At least few RADIUS servers (Aegis v1.1.6;
* but not v1.1.4; and Cisco ACS) seem to be
* terminating PEAPv1 (Aegis) or PEAPv0 (Cisco
* ACS) session resumption with outer
* EAP-Success. This does not seem to follow
* draft-josefsson-pppext-eap-tls-eap-05.txt
* section 4.2, so only allow this if EAP
* workarounds are enabled.
*/
wpa_printf(MSG_DEBUG, "EAP-PEAP: Workaround - "
"allow outer EAP-Success to "
"terminate PEAP resumption");
ret->decision = DECISION_COND_SUCC;
data->phase2_success = 1;
}
data->resuming = 0;
}
if (res == 2) {
struct wpabuf msg;
/*
* Application data included in the handshake message.
*/
wpabuf_free(data->pending_phase2_req);
data->pending_phase2_req = resp;
resp = NULL;
wpabuf_set(&msg, pos, left);
res = eap_peap_decrypt(sm, data, ret, req, &msg,
&resp);
}
}
if (ret->methodState == METHOD_DONE) {
ret->allowNotifications = FALSE;
}
if (res == 1) {
wpabuf_free(resp);
return eap_peer_tls_build_ack(id, EAP_TYPE_PEAP,
data->peap_version);
}
return resp;
}
static Boolean eap_peap_has_reauth_data(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
return tls_connection_established(sm->ssl_ctx, data->ssl.conn) &&
data->phase2_success;
}
static void eap_peap_deinit_for_reauth(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
wpabuf_free(data->pending_phase2_req);
data->pending_phase2_req = NULL;
data->crypto_binding_used = 0;
}
static void * eap_peap_init_for_reauth(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
os_free(data->key_data);
data->key_data = NULL;
if (eap_peer_tls_reauth_init(sm, &data->ssl)) {
os_free(data);
return NULL;
}
if (data->phase2_priv && data->phase2_method &&
data->phase2_method->init_for_reauth)
data->phase2_method->init_for_reauth(sm, data->phase2_priv);
data->phase2_success = 0;
data->phase2_eap_success = 0;
data->phase2_eap_started = 0;
data->resuming = 1;
sm->peap_done = FALSE;
return priv;
}
static int eap_peap_get_status(struct eap_sm *sm, void *priv, char *buf,
size_t buflen, int verbose)
{
struct eap_peap_data *data = priv;
int len, ret;
len = eap_peer_tls_status(sm, &data->ssl, buf, buflen, verbose);
if (data->phase2_method) {
ret = os_snprintf(buf + len, buflen - len,
"EAP-PEAPv%d Phase2 method=%s\n",
data->peap_version,
data->phase2_method->name);
if (ret < 0 || (size_t) ret >= buflen - len)
return len;
len += ret;
}
return len;
}
static Boolean eap_peap_isKeyAvailable(struct eap_sm *sm, void *priv)
{
struct eap_peap_data *data = priv;
return data->key_data != NULL && data->phase2_success;
}
static u8 * eap_peap_getKey(struct eap_sm *sm, void *priv, size_t *len)
{
struct eap_peap_data *data = priv;
u8 *key;
if (data->key_data == NULL || !data->phase2_success)
return NULL;
key = os_malloc(EAP_TLS_KEY_LEN);
if (key == NULL)
return NULL;
*len = EAP_TLS_KEY_LEN;
if (data->crypto_binding_used) {
u8 csk[128];
peap_prfplus(data->peap_version, data->ipmk, 40,
"Session Key Generating Function",
(u8 *) "", 0, csk, sizeof(csk));
wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: CSK", csk, sizeof(csk));
os_memcpy(key, csk, EAP_TLS_KEY_LEN);
wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Derived key",
key, EAP_TLS_KEY_LEN);
} else
os_memcpy(key, data->key_data, EAP_TLS_KEY_LEN);
return key;
}
int eap_peer_peap_register(void)
{
struct eap_method *eap;
int ret;
eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
EAP_VENDOR_IETF, EAP_TYPE_PEAP, "PEAP");
if (eap == NULL)
return -1;
eap->init = eap_peap_init;
eap->deinit = eap_peap_deinit;
eap->process = eap_peap_process;
eap->isKeyAvailable = eap_peap_isKeyAvailable;
eap->getKey = eap_peap_getKey;
eap->get_status = eap_peap_get_status;
eap->has_reauth_data = eap_peap_has_reauth_data;
eap->deinit_for_reauth = eap_peap_deinit_for_reauth;
eap->init_for_reauth = eap_peap_init_for_reauth;
ret = eap_peer_method_register(eap);
if (ret)
eap_peer_method_free(eap);
return ret;
}