eap_peap.c

Go to the documentation of this file.

/*
 * 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 "crypto/tls.h"
#include "eap_common/eap_tlv_common.h"
#include "eap_common/eap_peap_common.h"
#include "eap_i.h"
#include "eap_tls_common.h"
#include "eap_config.h"
#include "tncc.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 */
        int reauth; /* reauthentication */
        u8 *key_data;

        struct wpabuf *pending_phase2_req;
        enum { NO_BINDING, OPTIONAL_BINDING, REQUIRE_BINDING } crypto_binding;
        int crypto_binding_used;
        u8 binding_nonce[32];
        u8 ipmk[40];
        u8 cmk[20];
        int soh; /* Whether IF-TNCCS-SOH (Statement of Health; Microsoft NAP)
                  * is enabled. */
};


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");
        }

        if (os_strstr(phase1, "crypto_binding=0")) {
                data->crypto_binding = NO_BINDING;
                wpa_printf(MSG_DEBUG, "EAP-PEAP: Do not use cryptobinding");
        } else if (os_strstr(phase1, "crypto_binding=1")) {
                data->crypto_binding = OPTIONAL_BINDING;
                wpa_printf(MSG_DEBUG, "EAP-PEAP: Optional cryptobinding");
        } else if (os_strstr(phase1, "crypto_binding=2")) {
                data->crypto_binding = REQUIRE_BINDING;
                wpa_printf(MSG_DEBUG, "EAP-PEAP: Require cryptobinding");
        }

#ifdef EAP_TNC
        if (os_strstr(phase1, "tnc=soh2")) {
                data->soh = 2;
                wpa_printf(MSG_DEBUG, "EAP-PEAP: SoH version 2 enabled");
        } else if (os_strstr(phase1, "tnc=soh1")) {
                data->soh = 1;
                wpa_printf(MSG_DEBUG, "EAP-PEAP: SoH version 1 enabled");
        } else if (os_strstr(phase1, "tnc=soh")) {
                data->soh = 2;
                wpa_printf(MSG_DEBUG, "EAP-PEAP: SoH version 2 enabled");
        }
#endif /* EAP_TNC */

        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 = OPTIONAL_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);
}


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 > isk_len)
                key_len = isk_len;
        os_memcpy(isk, key, key_len);
        os_free(key);

        return 0;
}


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 (data->reauth &&
            tls_connection_resumed(sm->ssl_ctx, data->ssl.conn)) {
                /* Fast-connect: IPMK|CMK = TK */
                os_memcpy(data->ipmk, tk, 40);
                wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: IPMK from TK",
                                data->ipmk, 40);
                os_memcpy(data->cmk, tk + 40, 20);
                wpa_hexdump_key(MSG_DEBUG, "EAP-PEAP: CMK from TK",
                                data->cmk, 20);
                return 0;
        }

        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));

        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;

        /* 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, data->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;
}


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;
        os_memcpy(data->binding_nonce, pos, 32);
        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;
        wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Compound_MAC data",
                    buf, sizeof(buf));
        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");
                wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Received MAC",
                            pos, SHA1_MAC_LEN);
                wpa_hexdump(MSG_DEBUG, "EAP-PEAP: Expected MAC",
                            mac, SHA1_MAC_LEN);
                return -1;
        }

        wpa_printf(MSG_DEBUG, "EAP-PEAP: Valid cryptobinding TLV received");

        return 0;
}


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;
                        crypto_tlv = NULL; /* do not include Cryptobinding TLV
                                            * in response, if the received
                                            * cryptobinding was invalid. */
                }
        } 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;
        case EAP_TYPE_EXPANDED:
#ifdef EAP_TNC
                if (data->soh) {
                        const u8 *epos;
                        size_t eleft;

                        epos = eap_hdr_validate(EAP_VENDOR_MICROSOFT, 0x21,
                                                req, &eleft);
                        if (epos) {
                                struct wpabuf *buf;
                                wpa_printf(MSG_DEBUG,
                                           "EAP-PEAP: SoH EAP Extensions");
                                buf = tncc_process_soh_request(data->soh,
                                                               epos, eleft);
                                if (buf) {
                                        *resp = eap_msg_alloc(
                                                EAP_VENDOR_MICROSOFT, 0x21,
                                                wpabuf_len(buf),
                                                EAP_CODE_RESPONSE,
                                                hdr->identifier);
                                        if (*resp == NULL) {
                                                ret->methodState = METHOD_DONE;
                                                ret->decision = DECISION_FAIL;
                                                return -1;
                                        }
                                        wpabuf_put_buf(*resp, buf);
                                        wpabuf_free(buf);
                                        break;
                                }
                        }
                }
#endif /* EAP_TNC */
                /* fall through */
        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;
                                data->phase2_priv =
                                        data->phase2_method->init(sm);
                                sm->init_phase2 = 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_TLS_VERSION_MASK,
                        data->peap_version);
                if ((flags & EAP_TLS_VERSION_MASK) < data->peap_version)
                        data->peap_version = flags & EAP_TLS_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;
        data->reauth = 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];
                /*
                 * Note: It looks like Microsoft implementation requires null
                 * termination for this label while the one used for deriving
                 * IPMK|CMK did not use null termination.
                 */
                peap_prfplus(data->peap_version, data->ipmk, 40,
                             "Session Key Generating Function",
                             (u8 *) "\00", 1, 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;
}

---

wpa_supplicant
Author(s): Package maintained by Blaise Gassend
autogenerated on Fri Jan 11 10:04:04 2013