eap_peap.c

IEEE802.11 a/b/g 客户端应用程序源代码

	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;
	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(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;
				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);