dhcp_service_api.h

00001 /*
00002  * Copyright (c) 2013-2015 ARM Limited. All rights reserved.
00003  *
00004  * SPDX-License-Identifier: LicenseRef-PBL
00005  *
00006  * Licensed under the Permissive Binary License, Version 1.0 (the "License"); you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  * https://www.mbed.com/licenses/PBL-1.0
00010  *
00011  * See the License for the specific language governing permissions and limitations under the License.
00012  *
00013  */
00014 
00015 #ifndef DHCP_SERVICE_API_H_
00016 #define DHCP_SERVICE_API_H_
00017 
00018 #include <ns_types.h>
00019 /**
00020  * \file dhcp_service_api.h
00021  * \brief DHCP server connection interfaces
00022  *
00023  * \section dhcp-service DHCP Service Instance
00024  * - dhcp_service_init(), Initializes a DHCP service.
00025  * - dhcp_service_delete(), Removes the DHCP service.
00026  *
00027  * \section dhcp-msg DHCP Service Messages
00028  * - dhcp_service_send_req(), Sends out DHCP request messages.
00029  * - dhcp_service_send_resp(), Sends out DHCP response messages.
00030  *
00031  * \section dhcp-tim DHCP Service Timers (retry timers)
00032  * - dhcp_service_send_req(), Sends out DHCP request messages.
00033  * - dhcp_service_set_retry_timers(), Sets the retransmission parameters.
00034  * - dhcp_service_req_remove(), Stops retrying and retransmissions.
00035  * - dhcp_service_timer_tick(), Indicates if a timeout occurred.
00036  *
00037  */
00038 
00039 /** Defines Debug Trace String for DHCP service */
00040 #define DHCP_SERVICE_API_TRACE_STR "DHcS"
00041 
00042 /*
00043  * Return values for callbacks
00044  */
00045 
00046 /** Message belongs to someone else. */
00047 #define RET_MSG_NOT_MINE 0
00048 /** Message is handled. */
00049 #define RET_MSG_ACCEPTED 1
00050 /** Message is not the final one and needs to hold on a bit. */
00051 #define RET_MSG_WAIT_ANOTHER -1
00052 /** Message is unexpected or corrupted. */
00053 #define RET_MSG_CORRUPTED -2
00054 
00055 /** \name DHCP options */
00056 ///@{
00057 #define TX_OPT_NONE                     0x00    /**< No options. */
00058 #define TX_OPT_USE_SHORT_ADDR           0x01    /**< Use short addresses. */
00059 #define TX_OPT_MULTICAST_HOP_LIMIT_64   0x02    /**< Use multicast hop limit of 64. */
00060 ///@}
00061 
00062 /**
00063  * \brief DHCP Service receive callback.
00064  *
00065  * When the DHCP service receives a DHCP message it will go through a list of registered DHCP services instances
00066  * until some instance acknowledges that the message belongs to it.
00067  * \param instance_id An instance of registered server.
00068  * \param msg_tr_id The message transaction ID.
00069  * \param msg_ptr An allocated message pointer. Should not deallocate unless RET_MSG_ACCEPTED returned (then responsibility of client).
00070  * \param msg_len The length of the message.
00071  *
00072  * Return values
00073  * \return RET_MSG_ACCEPTED - Message is handled.
00074  * \return RET_MSG_CORRUPTED - Message is corrupted.
00075  * \return RET_MSG_NOT_MINE - Message belongs to someone else.
00076  */
00077 
00078 typedef int (dhcp_service_receive_req_cb)(uint16_t instance_id, uint32_t msg_tr_id, uint8_t msg_name, uint8_t *msg_ptr, uint16_t msg_len);
00079 
00080 /**
00081  * \brief DHCP Service Message Response callback.
00082  *
00083  * When the DHCP service receives a response to a DHCP message, this callback receives it.
00084  *
00085  * \param instance_id An instance of a registered server.
00086  * \param ptr A pointer for the client object.
00087  * \param msg_ptr An allocated message pointer. Should not deallocate unless RET_MSG_ACCEPTED returned (then responsibility of client).
00088  * \param msg_len The length of the message.
00089  *
00090  * Return values
00091  * \return RET_MSG_ACCEPTED - Message is handled
00092  * \return RET_MSG_WAIT_ANOTHER - This message was not the last one for this transaction and a new reply is expected.
00093  */
00094 
00095 typedef int (dhcp_service_receive_resp_cb)(uint16_t instance_id, void *ptr, uint8_t msg_name,  uint8_t *msg_ptr, uint16_t msg_len);
00096 
00097 
00098 /**
00099  * \brief Initialize the server instance.
00100  *
00101  * Creates and shares the socket for other DHCP services.
00102  *
00103  * \return Instance ID that is used to identify the service.
00104  */
00105 
00106 uint16_t dhcp_service_init(int8_t interface_id, dhcp_service_receive_req_cb *receive_req_cb);
00107 
00108 /**
00109 * \brief Deletes a server instance.
00110 *
00111 * Removes all data related to this instance.
00112 *
00113 * \param instance The instance ID of the registered server.
00114 */
00115 void dhcp_service_delete(uint16_t instance);
00116 
00117 /**
00118 * \brief Sends a DHCP response message.
00119 *
00120 * \param msg_tr_id The message transaction ID.
00121 * \param options Options for this request.
00122 * \param msg_ptr An allocated message pointer. Should not deallocate unless RET_MSG_ACCEPTED returned (then responsibility of client).
00123 * \param msg_len The length of the message.
00124 *
00125 * \return 0, if everything went fine.
00126 * \return -1, if error occurred.
00127 */
00128 int dhcp_service_send_resp(uint32_t msg_tr_id, uint8_t options, uint8_t *msg_ptr, uint16_t msg_len);
00129 
00130 
00131 /**
00132  * \brief Sends DHCP request message.
00133  *
00134  * Service takes care of retransmissions.
00135  *
00136  * \param instance_id The instance ID of the registered server.
00137  * \param options Options for this request.
00138  * \param ptr A void pointer to the client object.
00139  * \param addr The address of the server.
00140  * \param msg_ptr An allocated message pointer. This pointer is the responsibility of the service after this call.
00141  * \param msg_len The length of the message.
00142  * \param receive_resp_cb Callback pointer
00143  *
00144  * \return Transaction ID of the DHCP transaction
00145  * \return 0, if error occurred.
00146  */
00147 uint32_t dhcp_service_send_req(uint16_t instance_id, uint8_t options, void *ptr, const uint8_t addr[static 16], uint8_t *msg_ptr, uint16_t msg_len, dhcp_service_receive_resp_cb *receive_resp_cb);
00148 
00149 /**
00150  * \brief Setting retransmission parameters.
00151  *
00152  * Sets the retransmission parameters for this transaction.
00153  *
00154  * \param msg_tr_id The message transaction ID.
00155  * \param timeout_init An initial timeout value.
00156  * \param timeout_max The maximum timeout value when initial timeout is doubled with every retry.
00157  * \param retrans_max The maximum number of retries after which an error is received.
00158  *
00159  */
00160 void dhcp_service_set_retry_timers(uint32_t msg_tr_id, uint16_t timeout_init, uint16_t timeout_max, uint8_t retrans_max);
00161 
00162 /**
00163  * \brief Stops transactions for a message (retransmissions).
00164  *
00165  * Clears off sending retransmissions for a particular message transaction by finding it via its message transaction ID.
00166  *
00167  * \param msg_tr_id The message transaction ID.
00168  *
00169  */
00170 void dhcp_service_req_remove(uint32_t msg_tr_id);
00171 
00172 /**
00173  * \brief Timer tick function for retransmissions.
00174  *
00175  * Retransmission timer ticks should be increased with 100ms interval, if necessary. One tick is one millisecond.
00176  *
00177  */
00178 bool dhcp_service_timer_tick(uint16_t ticks);
00179 
00180 
00181 #endif //DHCP_SERVICE_API_H_