-/****h* silccore/silcpacket.h
- *
- * NAME
- *
- * silcpacket.h
- *
- * COPYRIGHT
- *
- * Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
- *
- * Copyright (C) 1997 - 2001 Pekka Riikonen
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+/*
+
+ silcpacket.h
+
+ Author: Pekka Riikonen <priikone@silcnet.org>
+
+ Copyright (C) 1997 - 2005 Pekka Riikonen
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+*/
+
+/****h* silccore/Packet Protocol Interface
*
* DESCRIPTION
*
#ifndef SILCPACKET_H
#define SILCPACKET_H
-/* Amount of bytes to be read from the socket connection at once. */
-#define SILC_PACKET_READ_SIZE 16384
+/* XXX many of these could go to silcpacket_i.h */
-/* Default byte size of the packet. This can be set larger if this
- is not enough, we shall see. */
-#define SILC_PACKET_DEFAULT_SIZE 2048
-
-/* Header length without source and destination ID's. */
-#define SILC_PACKET_HEADER_LEN 8 + 2
-
-/* Minimum length of SILC Packet Header. This much is decrypted always
- when packet is received to be able to get all the relevant data out
- from the header. */
-#define SILC_PACKET_MIN_HEADER_LEN 16 + 2
-
-/* Maximum padding length */
-#define SILC_PACKET_MAX_PADLEN 16
-
-/* Minimum packet length */
-#define SILC_PACKET_MIN_LEN (SILC_PACKET_HEADER_LEN + 1)
+/* Maximum packet length */
+#define SILC_PACKET_MAX_LEN 0xffff
/* Maximum length of ID */
-#define SILC_PACKET_MAX_ID_LEN 16
+#define SILC_PACKET_MAX_ID_LEN 28
/****d* silccore/SilcPacketAPI/SilcPacketType
*
* NAME
- *
- * typedef unsigned char SilcPacketType;
+ *
+ * typedef SilcUInt8 SilcPacketType;
*
* DESCRIPTION
*
*
* SOURCE
*/
-typedef unsigned char SilcPacketType;
+typedef SilcUInt8 SilcPacketType;
/* SILC Packet types. */
#define SILC_PACKET_NONE 0 /* NULL, never sent */
#define SILC_PACKET_REKEY_DONE 23 /* Re-key done */
#define SILC_PACKET_HEARTBEAT 24 /* Heartbeat */
#define SILC_PACKET_KEY_AGREEMENT 25 /* Key Agreement request */
-#define SILC_PACKET_CELL_ROUTERS 26 /* Cell routers backup */
+#define SILC_PACKET_RESUME_ROUTER 26 /* Backup router resume */
+#define SILC_PACKET_FTP 27 /* File Transfer */
+#define SILC_PACKET_RESUME_CLIENT 28 /* Client resume */
#define SILC_PACKET_PRIVATE 200 /* Private range start */
#define SILC_PACKET_MAX 255 /* RESERVED */
/***/
-/****d* silccore/SilcPacketAPI/SilcPacketVersion
- *
- * NAME
- *
- * typedef unsigned char SilcPacketVersion;
- *
- * DESCRIPTION
- *
- * SILC packet version type definition.
- *
- ***/
-typedef unsigned char SilcPacketVersion;
-
/****d* silccore/SilcPacketAPI/SilcPacketFlags
*
* NAME
- *
- * typedef unsigned char SilcPacketFlags;
+ *
+ * typedef SilcUInt8 SilcPacketFlags;
*
* DESCRIPTION
*
*
* SOURCE
*/
-typedef unsigned char SilcPacketFlags;
+typedef SilcUInt8 SilcPacketFlags;
/* All defined packet flags */
#define SILC_PACKET_FLAG_NONE 0x00 /* No flags */
#define SILC_PACKET_FLAG_PRIVMSG_KEY 0x01 /* Private message key */
#define SILC_PACKET_FLAG_LIST 0x02 /* Packet is a list */
#define SILC_PACKET_FLAG_BROADCAST 0x04 /* Packet is a broadcast */
-/***/
+#define SILC_PACKET_FLAG_COMPRESSED 0x08 /* Payload is compressed */
-/* Rest of flags still available
-#define SILC_PACKET_FLAG_XXX 0x08
-#define SILC_PACKET_FLAG_XXX 0x10
-#define SILC_PACKET_FLAG_XXX 0x20
-#define SILC_PACKET_FLAG_XXX 0x40
-#define SILC_PACKET_FLAG_XXX 0x80
-*/
+/* Impelemntation specific flags */
+#define SILC_PACKET_FLAG_LONG_PAD 0x10 /* Use maximum padding */
+/***/
-/****s* silccore/SilcPacketAPI/SilcPacketContext
+/****s* silccore/SilcPacketAPI/SilcPacketEngine
*
* NAME
- *
- * typedef struct { ... } SilcPacketContext;
- *
- * DESCRIPTION
- *
- * In packet sending this is filled and sent to silc_packet_assemble
- * which then uses it to assemble new packet. In packet reception pointer
- * to this context is sent to silc_packet_parse which parses the packet
- * and returns the relevant information to this structure. On packet
- * reception returned ID's are always the hash values of the ID's from
- * the packet.
*
- * Short description of the fields following:
+ * typedef struct SilcPacketEngineStruct *SilcPacketEngine;
*
- * SilcBuffer buffer
- *
- * The data buffer.
- *
- * SilcPacketType type
+ * DESCRIPTION
*
- * Type of the packet. Types are defined below.
+ * The packet engine context, allocated by silc_packet_engine_start.
+ * The engine is destroyed with silc_packet_engine_stop.
*
- * SilcPacketFlags flags
+ ***/
+typedef struct SilcPacketEngineStruct *SilcPacketEngine;
+
+/****s* silccore/SilcPacketAPI/SilcPacketStream
*
- * Packet flags. Flags are defined above.
+ * NAME
*
- * unsigned char *src_id
- * uint16 src_id_len
- * unsigned char src_id_type
+ * typedef struct SilcPacketStreamStruct *SilcPacketStream;
*
- * Source ID, its length and type. On packet reception retuned ID's
- * are always the hash values of the ID's from the packet.
+ * DESCRIPTION
*
- * unsigned char *dst_id;
- * uint16 dst_id_len;
- * unsigned char src_id_type;
+ * The packet stream context, allocated by silc_packet_stream_create.
+ * The stream is destroyed with silc_packet_stream_destroy.
*
- * Destination ID, its length and type. On packet reception retuned
- * ID's are always the hash values of the ID's from the packet.
+ ***/
+typedef struct SilcPacketStreamStruct *SilcPacketStream;
+
+/****s* silccore/SilcPacketAPI/SilcPacket
*
- * uint16 truelen
- * uint16 padlen
+ * NAME
*
- * The true lenght of the packet and the padded length of the packet.
- * These may be set by the caller before calling any of the
- * silc_packet_* routines. If not provided the library will calculate
- * the values.
+ * typedef struct SilcPacketStruct *SilcPacket;
*
- * in users;
+ * DESCRIPTION
*
- * Reference counter for this context. The context is freed only
- * after the reference counter hits zero. The counter is added
- * calling silc_packet_context_dup and decreased by calling the
- * silc_packet_context_free.
+ * The SilcPacket is returned by the packet engine in the SilcPacketReceive
+ * callback. The application can parse the data payload from the
+ * SilcPacket. Also packet type, flags, and sender and destination
+ * IDs are available. The application must free the packet with the
+ * silc_packet_free function.
*
- ***/
-typedef struct {
- SilcBuffer buffer;
- SilcPacketType type;
- SilcPacketFlags flags;
-
- unsigned char *src_id;
- uint16 src_id_len;
- unsigned char src_id_type;
-
- unsigned char *dst_id;
- uint16 dst_id_len;
- unsigned char dst_id_type;
-
- uint16 truelen;
- uint16 padlen;
-
- /* Back pointers */
- void *context;
- SilcSocketConnection sock;
-
- int users;
-} SilcPacketContext;
+ * SOURCE
+ */
+typedef struct SilcPacketStruct {
+ struct SilcPacketStruct *next;
+ SilcBufferStruct buffer; /* Packet data payload */
+ unsigned char *src_id; /* Source ID */
+ unsigned char *dst_id; /* Destination ID */
+ unsigned int src_id_len : 6; /* Source ID length */
+ unsigned int src_id_type : 2; /* Source ID type */
+ unsigned int dst_id_len : 6; /* Destination ID length */
+ unsigned int dst_id_type : 2; /* Destination ID type */
+ SilcPacketType type; /* Packet type */
+ SilcPacketFlags flags; /* Packet flags */
+} *SilcPacket;
+/***/
-/****s* silccore/SilcPacketAPI/SilcPacketParserContext
+/****d* silcutil/SilcPacketAPI/SilcPacketError
*
* NAME
- *
- * typedef struct { ... } SilcPacketParserContext;
- *
- * DESCRIPTION
*
- * This context is used in packet reception when silc_packet_receive_process
- * function calls parser callback that performs the actual packet decryption
- * and parsing. This context is sent as argument to the parser function.
- * This context must be free'd by the parser callback function.
+ * typedef enum { ... } SilcPacketError
*
- * Following description of the fields:
+ * DESCRIPTION
*
- * SilcPacketContext *packet
+ * Packet errors. This is returned in the error callback. If application
+ * needs the actual lower level stream error, it needs to retrieve it
+ * from the actual stream.
*
- * The actual packet received from the network. In this phase the
- * context is not parsed, only the packet->buffer is allocated and
- * it includes the raw packet data, which is encrypted.
+ * SOURCE
+ */
+typedef enum {
+ SILC_PACKET_ERR_READ, /* Error while reading */
+ SILC_PACKET_ERR_WRITE, /* Error while writing */
+ SILC_PACKET_ERR_MAC_FAILED, /* Packet MAC check failed */
+ SILC_PACKET_ERR_DECRYPTION_FAILED, /* Packet decryption failed */
+ SILC_PACKET_ERR_MALFORMED, /* Packet is malformed */
+ SILC_PACKET_ERR_NO_MEMORY, /* System out of memory */
+} SilcPacketError;
+/***/
+
+/****f* silccore/SilcPacketAPI/SilcPacketReceiveCb
*
- * SilcSocketConnection sock
+ * SYNOPSIS
*
- * The associated connection.
+ * typedef void (*SilcPacketReceiveCb)(SilcPacketEngine engine,
+ * SilcPacketStream stream,
+ * SilcPacket packet,
+ * void *callback_context,
+ * void *app_context);
*
- * void *context
+ * DESCRIPTION
*
- * User context that is sent to the silc_packet_receive_process
- * function. This usually includes application and connection specific
- * data.
+ * The packet receive callback is called by the packet engine when a new
+ * SILC Packet has arrived. The application must free the returned
+ * SilcPacket with silc_packet_free. This callback is set in the
+ * SilcPacketCallbacks structure.
*
***/
-typedef struct {
- SilcPacketContext *packet;
- SilcSocketConnection sock;
- void *context;
-} SilcPacketParserContext;
+typedef void (*SilcPacketReceiveCb)(SilcPacketEngine engine,
+ SilcPacketStream stream,
+ SilcPacket packet,
+ void *callback_context,
+ void *app_context);
-/****f* silccore/SilcPacketAPI/SilcPacketParserCallback
+/****f* silccore/SilcPacketAPI/SilcPacketEosCb
*
* SYNOPSIS
*
- * typedef void (*SilcPacketParserCallback)(SilcPacketParserContext
- * *parse_context);
+ * typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
+ * SilcPacketStream stream,
+ * void *callback_context,
+ * void *app_context);
*
* DESCRIPTION
*
- * This callback is given to the silc_packet_receive_process function.
- * The callback is called by the library every time a packet is
- * received from the network. After the packet has been decrypted
- * and at least partially parsed it is passed to the application
- * for further parsing using this callback and the SilcPacketParserContext
- * context. The application receiving the SilcPacketParserContext
- * must free it.
+ * The End Of Stream (EOS) callback, that is called by the packet engine
+ * when the underlaying stream has ended. No more data can be sent to
+ * the stream or read from it. The `stream' must be destroyed by
+ * calling the silc_packet_stream_destroy. This callback is set in the
+ * SilcPacketCallbacks structure.
*
***/
-typedef void (*SilcPacketParserCallback)(SilcPacketParserContext
- *parse_context);
+typedef void (*SilcPacketEosCb)(SilcPacketEngine engine,
+ SilcPacketStream stream,
+ void *callback_context,
+ void *app_context);
-/****f* silccore/SilcPacketAPI/SilcPacketCheckDecrypt
+/****f* silccore/SilcPacketAPI/SilcPacketErrorCb
*
* SYNOPSIS
*
- * typedef int (*SilcPacketCheckDecrypt)(SilcPacketType packet_type,
- * SilcBuffer buffer,
- * SilcPacketContext *packet,
- * void *context);
+ * typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
+ * SilcPacketStream stream,
+ * SilcPacketError error,
+ * void *callback_context,
+ * void *app_context);
*
* DESCRIPTION
*
- * This callback function relates to the checking whether the packet is
- * normal packet or special packet and how it should be processed. If
- * the callback returns TRUE the packet is normal and FALSE if the packet
- * is special and requires special procesing. Some of the packets in
- * SILC are special (like channel message packets that are encrypted
- * using channel specific keys) and requires special processing. That
- * is the reason for this callback function.
- *
- * The library will call this function if provided for the
- * silc_packet_decrypt function. The `packet_type' is the type of
- * packet received (this is also actually the first time application
- * receives information of the received packet, next time it receives
- * it is when the SilcPacketParserCallback function is called),
- * the `buffer' is the raw packet data the `packet' the allocated
- * SilcPacketContext that is filled when parsing the packet and `context'
- * is application specific user context.
+ * The error callback that is called by the packet engine if an error
+ * occurs. The `error' will indicate the error. This callback is set
+ * in the SilcPacketCallbacks structure.
*
***/
-typedef int (*SilcPacketCheckDecrypt)(SilcPacketType packet_type,
- SilcBuffer buffer,
- SilcPacketContext *packet,
- void *context);
+typedef void (*SilcPacketErrorCb)(SilcPacketEngine engine,
+ SilcPacketStream stream,
+ SilcPacketError error,
+ void *callback_context,
+ void *app_context);
-/* Macros */
-
-/****d* silccore/SilcPacketAPI/SILC_PACKET_LENGTH
+/****s* silccore/SilcPacketAPI/SilcPacketStream
*
* NAME
- *
- * #define SILC_PACKET_LENGTH ...
+ *
+ * typedef struct SilcPacketStreamStruct *SilcPacketStream;
*
* DESCRIPTION
*
- * Returns true length of the packet and padded length of the packet.
- * This is primarily used by the libary in packet parsing phase but
- * the application may use it as well if needed.
+ * This structure is sent as argument to the silc_packet_engine_start
+ * function to set the callback functions for the packet engine. The
+ * packet engine will call the callbacks when necessary. Application
+ * must always be provided for the packet engine.
*
* SOURCE
*/
-#define SILC_PACKET_LENGTH(__packet, __ret_truelen, __ret_padlen) \
-do { \
- SILC_GET16_MSB((__ret_truelen), (__packet)->data); \
- (__ret_padlen) = (((__ret_truelen) - 2) + \
- SILC_PACKET_MAX_PADLEN) & ~(SILC_PACKET_MAX_PADLEN - 1); \
-} while(0)
+typedef struct {
+ SilcPacketReceiveCb packet_receive; /* Called when packet is received */
+ SilcPacketEosCb eos; /* Called on end of stream */
+ SilcPacketErrorCb error; /* Called on an error */
+} SilcPacketCallbacks;
/***/
-/****d* silccore/SilcPacketAPI/SILC_PACKET_PADLEN
+/* Prototypes */
+
+/****f* silccore/SilcPacketAPI/silc_packet_engine_start
*
- * NAME
- *
- * #define SILC_PACKET_PADLEN ...
+ * SYNOPSIS
+ *
+ * SilcPacketEngine
+ * silc_packet_engine_start(SilcSchedule schedule, SilcRng rng, bool router,
+ * SilcPacketCallbacks *callbacks,
+ * void *callback_context);
*
* DESCRIPTION
*
- * Returns the length of the padding in the packet. This is used
- * by various library routines to determine needed padding length.
+ * Create new packet engine for processing incoming and outgoing packets.
+ * If `rng' is non-NULL that RNG will be used to create necessary random
+ * numbers during packet processing. If NULL, Global RNG will be used.
+ * If `router' is TRUE then the application is considered to be router
+ * server, and certain packets are handled differently. Client and normal
+ * server must set it to FALSE. The `callbacks' is a SilcPacketCallbacks
+ * structure provided by the caller which includes the callbacks that is
+ * called when for example packet is received, or end of stream is called
*
- * SOURCE
- */
-#define SILC_PACKET_PADLEN(__packetlen) \
- SILC_PACKET_MAX_PADLEN - ((__packetlen) - 2) % SILC_PACKET_MAX_PADLEN;
-/***/
+ * NOTES
+ *
+ * The packet engine is thread safe. Also the `schedule' and `rng' are
+ * thread safe. You can use one packet engine in multi threaded
+ * application.
+ *
+ ***/
+SilcPacketEngine
+silc_packet_engine_start(SilcSchedule schedule, SilcRng rng, bool router,
+ SilcPacketCallbacks *callbacks,
+ void *callback_context);
-/* Prototypes */
+/****f* silccore/SilcPacketAPI/silc_packet_engine_stop
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_engine_stop(SilcPacketEngine engine);
+ *
+ * DESCRIPTION
+ *
+ * Stop the packet engine. No new packets can be sent or received after
+ * calling this, and the `engine' will become invalid.
+ *
+ ***/
+void silc_packet_engine_stop(SilcPacketEngine engine);
-/****f* silccore/SilcPacketAPI/silc_packet_write
+/****f* silccore/SilcPacketAPI/silc_packet_stream_create
*
* SYNOPSIS
*
- * int silc_packet_write(int sock, SilcBuffer src);
+ * SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
+ * SilcStream stream);
*
* DESCRIPTION
*
- * Writes data from encrypted buffer to the socket connection. If the
- * data cannot be written at once, it will be written later with a timeout.
- * The data is written from the data section of the buffer, not from head
- * or tail section. This automatically pulls the data section towards end
- * after writing the data.
+ * Create new packet stream and use the `stream' as underlaying stream.
+ * Usually the `stream' would be a socket stream, but it can be any
+ * stream. After this function returns, packets can immediately be
+ * sent to or received from the stream.
+ *
+ * NOTES
+ *
+ * SilcPacketStream cannot be used with silc_stream_* routines (such as
+ * silc_stream_read and silc_stream_write) because of its special nature.
+ * Use the silc_packet_send and the silc_packet_send_ext to send packets.
+ * To read packets you will receive the packet receive callback from
+ * packet engine. Destroy the stream with silc_packet_stream_destroy.
+ *
+ * If you need to send only one type of SILC packets, then it is possible
+ * to create SILC Packet Streamer with silc_packet_streamer_create, which
+ * can be used with silc_stream_read and silc_stream_write.
+ *
+ * The SilcPacketStream is not thread safe. If you share same stream
+ * with multiple threads concurrency control need to be employed. It
+ * is recommended to create new SilcPacketStream for every thread.
*
***/
-int silc_packet_write(int sock, SilcBuffer src);
+SilcPacketStream silc_packet_stream_create(SilcPacketEngine engine,
+ SilcStream stream);
-/****f* silccore/SilcPacketAPI/silc_packet_send
+/****f* silccore/SilcPacketAPI/silc_packet_stream_destroy
*
* SYNOPSIS
*
- * int silc_packet_send(SilcSocketConnection sock, int force_send);
+ * void silc_packet_stream_destroy(SilcPacketStream stream);
*
* DESCRIPTION
*
- * Actually sends the packet. This flushes the connections outgoing data
- * buffer. If data is sent directly to the network this returns the bytes
- * written, if error occured this returns -1 and if the data could not
- * be written directly to the network at this time this returns -2, in
- * which case the data should be queued by the caller and sent at some
- * later time. If `force_send' is TRUE this attempts to write the data
- * directly to the network, if FALSE, this returns -2.
+ * Destroy packet stream and the underlaying stream. This will also
+ * send end of stream to the underlaying stream.
*
***/
-int silc_packet_send(SilcSocketConnection sock, int force_send);
+void silc_packet_stream_destroy(SilcPacketStream stream);
-/****f* silccore/SilcPacketAPI/silc_packet_encrypt
+/****f* silccore/SilcPacketAPI/silc_packet_streamer_create
*
* SYNOPSIS
*
- * void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac,
- * SilcBuffer buffer, uint32 len);
+ * SilcStream silc_packet_streamer_create(SilcPacketStream stream,
+ * SilcPacketType packet_type,
+ * SilcPacketFlags packet_flags);
*
* DESCRIPTION
*
- * Encrypts a packet. This also creates HMAC of the packet before
- * encryption and adds the HMAC at the end of the buffer. This assumes
- * that there is enough free space at the end of the buffer to add the
- * computed HMAC. This is the normal way of encrypting packets, if some
- * other process of HMAC computing and encryption is needed this function
- * cannot be used.
+ * This function can be used to create a SILC Packet Streamer that will
+ * stream only one type of packet indicated by `packet_type' with packet
+ * flags `packet_flags'. This is special purpose function as usually
+ * multiple different types of packets need to be sent in application.
+ * There are cases however when creating streamer is simpler and more
+ * efficient. Cases such as file transfer stream or other data streams
+ * that only send and receive one type of packet. While it would be
+ * possible to use silc_packet_send function to send packets it is
+ * more efficient to create the SILC Packet Streamer and use the
+ * silc_stream_read and silc_stream_write functions.
+ *
+ * The encryption and decryption keys, and other information will be
+ * retrieved from the packet stream indicated by `stream', which must be
+ * created before creating the streamer.
+ *
+ * NOTES
+ *
+ * The packet type that is assocated with the packet stream `stream' will
+ * only be available through the returned SilcStream. That packet type
+ * will not be delivered to the packet callbacks. To return to the
+ * normal operation destroy the streamer silc_packet_streamer_destroy.
*
***/
-void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac,
- SilcBuffer buffer, uint32 len);
+SilcStream silc_packet_streamer_create(SilcPacketStream stream,
+ SilcPacketType packet_type,
+ SilcPacketFlags packet_flags);
-/****f* silccore/SilcPacketAPI/silc_packet_assemble
+/****f* silccore/SilcPacketAPI/silc_packet_streamer_destroy
*
* SYNOPSIS
*
- * void silc_packet_assemble(SilcPacketContext *ctx);
+ * void silc_packet_streamer_destroy(SilcStream stream);
*
* DESCRIPTION
*
- * Assembles a new packet to be ready for send out. The buffer sent as
- * argument must include the data to be sent and it must not be encrypted.
- * The packet also must have enough free space so that the SILC header
- * and padding maybe added to the packet. The packet is encrypted after
- * this function has returned.
+ * Destroys the created packet streamer. Use this function only for
+ * stream created with silc_packet_streamer_create. The packet type
+ * that was associated with the streamer can be received in the packet
+ * callbacks after the streamer is destroyed.
*
- * The buffer sent as argument should be something like following:
+ ***/
+void silc_packet_streamer_destroy(SilcStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
+ *
+ * SYNOPSIS
*
- * --------------------------------------------
- * | head | data | tail |
- * --------------------------------------------
- * ^ ^
- * 58 bytes x bytes
+ * SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
*
- * So that the SILC header and 1 - 16 bytes of padding can fit to
- * the buffer. After assembly the buffer might look like this:
+ * DESCRIPTION
*
- * --------------------------------------------
- * | data | |
- * --------------------------------------------
- * ^ ^
- * Start of assembled packet
+ * Returns the actual stream that is associated with the packet stream
+ * `stream'. The caller must not free the returned stream. The returned
+ * stream is the same pointer that was set for silc_packet_stream_create.
+ * This function couled be used for example when an error callback is
+ * called by the packet engine to retrieve the actual lower level error
+ * from the stream.
*
- * Packet construct is as follows (* = won't be encrypted):
+ ***/
+SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_callbacks
*
- * n bytes SILC Header
- * 2 bytes Payload length (*)
- * 1 byte Flags
- * 1 byte Packet type
- * 2 bytes Source ID Length
- * 2 bytes Destination ID Length
- * 1 byte Source ID Type
- * n bytes Source ID
- * 1 byte Destination ID Type
- * n bytes Destination ID
+ * SYNOPSIS
*
- * 1 - 16 bytes Padding
+ * void silc_packet_stream_callbacks(SilcPacketStream stream,
+ * SilcPacketCallbacks *callbacks,
+ * void *callback_context);
*
- * n bytes Data payload
+ * DESCRIPTION
*
- * All fields in the packet will be authenticated by MAC. The MAC is
- * not computed here, it must be computed separately before encrypting
- * the packet.
+ * This is optional function which can be used to set specific callbacks
+ * for the packet stream indicated by `stream'. If these are set then
+ * `callbacks' will be used instead of the ones set for the function
+ * silc_packet_engine_start. To reset the normal behaviour call this
+ * function again with `callbacks' as NULL. Note that the responsibility
+ * of handling end of stream, and error conditions moves to the layer
+ * calling this function since the original callbacks set in the
+ * silc_packet_engine_start will not be called.
*
***/
-void silc_packet_assemble(SilcPacketContext *ctx);
+void silc_packet_stream_callbacks(SilcPacketStream stream,
+ SilcPacketCallbacks *callbacks,
+ void *callback_context);
-/****f* silccore/SilcPacketAPI/silc_packet_send_prepare
+/****f* silccore/SilcPacketAPI/silc_packet_stream_ref
*
* SYNOPSIS
*
- * void silc_packet_send_prepare(SilcSocketConnection sock,
- * uint32 header_len,
- * uint32 padlen,
- * uint32 data_len);
+ * void silc_packet_stream_ref(SilcPacketStream stream);
*
* DESCRIPTION
*
- * Prepare outgoing data buffer for packet sending. This moves the data
- * area so that new packet may be added into it. If needed this allocates
- * more space to the buffer. This handles directly the connection's
- * outgoing buffer in SilcSocketConnection object.
+ * Increase reference counter for the stream indicated by `stream'. This
+ * can be used to take a reference for the stream. To unreference the
+ * stream call silc_packet_stream_unref function.
*
***/
-void silc_packet_send_prepare(SilcSocketConnection sock,
- uint32 header_len,
- uint32 padlen,
- uint32 data_len);
+void silc_packet_stream_ref(SilcPacketStream stream);
-/****f* silccore/SilcPacketAPI/silc_packet_read
+/****f* silccore/SilcPacketAPI/silc_packet_stream_unref
*
* SYNOPSIS
*
- * int silc_packet_read(int sock, SilcBuffer dest);
+ * void silc_packet_stream_unref(SilcPacketStream stream);
*
* DESCRIPTION
*
- * Reads data from the socket connection into the incoming data buffer.
- * However, this does not parse the packet, it only reads some amount from
- * the network. If there are more data available that can be read at a time
- * the rest of the data will be read later with a timeout and only after
- * that the packet is ready to be parsed.
+ * Decrease reference counter for the stream indicated by `stream'. If
+ * the counter hits zero the stream will be destroyed automatically.
*
- * The destination buffer sent as argument must be initialized before
- * calling this function, and, the data section and the start of the tail
- * section must be same. Ie. we add the read data to the tail section of
- * the buffer hence the data section is the start of the buffer.
+ ***/
+void silc_packet_stream_unref(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_set_context
*
- * This returns amount of bytes read or -1 on error or -2 on case where
- * all of the data could not be read at once.
+ * SYNOPSIS
+ *
+ * void silc_packet_set_context(SilcPacketStream stream, void *app_context);
+ *
+ * DESCRIPTION
+ *
+ * Set an application specific context to the stream. The context will
+ * be delivered to all callback functions, and it can be retrieved by
+ * calling silc_packet_get_context function as well. Note that this is
+ * separate packet stream specific context, and not the same as
+ * `callback_context' in silc_packet_engine_start. Both will be delivered
+ * to the callbacks.
*
***/
-int silc_packet_read(int sock, SilcBuffer dest);
+void silc_packet_set_context(SilcPacketStream stream, void *app_context);
-/****f* silccore/SilcPacketAPI/silc_packet_receive
+/****f* silccore/SilcPacketAPI/silc_packet_get_context
*
* SYNOPSIS
*
- * int silc_packet_receive(SilcSocketConnection sock);
+ * void *silc_packet_get_context(SilcPacketStream stream);
*
* DESCRIPTION
*
- * Receives packet from network and reads the data into connection's
- * incoming data buffer. If the data was read directly this returns the
- * read bytes, if error occured this returns -1, if the data could not
- * be read directly at this time this returns -2 in which case the data
- * should be read again at some later time, or If EOF occured this returns
- * 0.
+ * Returns the current set application context, or NULL if none is set.
*
***/
-int silc_packet_receive(SilcSocketConnection sock);
+void *silc_packet_get_context(SilcPacketStream stream);
-/****f* silccore/SilcPacketAPI/silc_packet_decrypt
+/****f* silccore/SilcPacketAPI/silc_packet_set_ciphers
*
* SYNOPSIS
*
- * int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
- * SilcBuffer buffer, SilcPacketContext *packet,
- * SilcPacketCheckDecrypt check_packet,
- * void *context);
+ * void silc_packet_set_ciphers(SilcPacketStream stream, SilcCipher send,
+ * SilcCipher receive);
*
* DESCRIPTION
*
- * Decrypts a packet. This assumes that typical SILC packet is the
- * packet to be decrypted and thus checks for normal and special SILC
- * packets and can handle both of them. This also computes and checks
- * the HMAC of the packet. If any other special or customized decryption
- * processing is required this function cannot be used. This returns
- * -1 on error, 0 when packet is normal packet and 1 when the packet
- * is special and requires special processing.
+ * Set ciphers to be used to encrypt sent packets, and decrypt received
+ * packets. This can be called multiple times to change the ciphers.
+ * In this case if old cipher is set it will be freed. If ciphers are
+ * not set packets will not be encrypted or decrypted.
*
- * The `check_packet' is a callback funtion that this function will
- * call. The callback relates to the checking whether the packet is
- * normal packet or special packet and how it should be processed. If
- * the callback return TRUE the packet is normal and FALSE if the packet
- * is special and requires special procesing.
+ ***/
+void silc_packet_set_ciphers(SilcPacketStream stream, SilcCipher send,
+ SilcCipher receive);
+
+/****f* silccore/SilcPacketAPI/silc_packet_get_ciphers
+ *
+ * SYNOPSIS
+ *
+ * bool silc_packet_get_ciphers(SilcPacketStream stream, SilcCipher *send,
+ * SilcCipher *receive);
+ *
+ * DESCRIPTION
+ *
+ * Returns the pointers of current ciphers from the `stream'. Returns
+ * FALSE if ciphers are not set.
*
***/
-int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac,
- SilcBuffer buffer, SilcPacketContext *packet,
- SilcPacketCheckDecrypt check_packet,
- void *context);
+bool silc_packet_get_ciphers(SilcPacketStream stream, SilcCipher *send,
+ SilcCipher *receive);
-/****f* silccore/SilcPacketAPI/silc_packet_receive_process
+/****f* silccore/SilcPacketAPI/silc_packet_set_hmacs
*
* SYNOPSIS
*
- * void silc_packet_receive_process(SilcSocketConnection sock,
- * SilcCipher cipher, SilcHmac hmac,
- * SilcPacketParserCallback parser,
- * void *context);
+ * void silc_packet_set_hmacs(SilcPacketStream stream, SilcHmac send,
+ * SilcHmac receive);
*
* DESCRIPTION
*
- * Processes the received data. This checks the received data and
- * calls parser callback that handles the actual packet decryption
- * and parsing. If more than one packet was received this calls the
- * parser multiple times. The parser callback will get context
- * SilcPacketParserContext that includes the packet and the `context'
- * sent to this function.
+ * Set HMACs to be used to create MACs for sent packets and to check
+ * MAC for received packets. This can be called multiple times to change
+ * the HMACs. In this case if old HMAC is set it will be freed. If
+ * HMACs are not set MACs are not generated or verified for packets.
*
***/
-void silc_packet_receive_process(SilcSocketConnection sock,
- SilcCipher cipher, SilcHmac hmac,
- SilcPacketParserCallback parser,
- void *context);
+void silc_packet_set_hmacs(SilcPacketStream stream, SilcHmac send,
+ SilcHmac receive);
-/****f* silccore/SilcPacketAPI/silc_packet_parse
+/****f* silccore/SilcPacketAPI/silc_packet_get_hmacs
*
* SYNOPSIS
*
- * SilcPacketType silc_packet_parse(SilcPacketContext *ctx);
+ * bool silc_packet_get_hmacs(SilcPacketStream stream, SilcHmac *send,
+ * SilcHmac *receive);
*
* DESCRIPTION
*
- * Parses the packet. This is called when a whole packet is ready to be
- * parsed. The buffer sent must be already decrypted before calling this
- * function. The len argument must be the true length of the packet. This
- * function returns the type of the packet. The data section of the
- * buffer is parsed, not head or tail sections.
+ * Returns the pointers of current HMACs from the `stream'. Returns
+ * FALSE if HMACs are not set.
*
***/
-SilcPacketType silc_packet_parse(SilcPacketContext *ctx);
+bool silc_packet_get_hmacs(SilcPacketStream stream, SilcHmac *send,
+ SilcHmac *receive);
-/****f* silccore/SilcPacketAPI/silc_packet_parse_special
+/****f* silccore/SilcPacketAPI/silc_packet_set_ids
*
* SYNOPSIS
*
- * SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx);
+ * bool silc_packet_set_ids(SilcPacketStream stream,
+ * SilcIdType src_id_type, const void *src_id
+ * SilcIdType dst_id_type, const void *dst_id);
*
* DESCRIPTION
*
- * Perform special SILC Packet header parsing. This is required to some
- * packet types that have the data payload encrypted with different key
- * than the header area plus padding of the packet. Hence, this parses
- * the header in a way that it does not take the data area into account
- * and parses the header and padding area only.
+ * Set the source ID and destinaion ID to be used when sending packets to
+ * this packet stream. The IDs to be used for a packet stream can be
+ * overridden when sending packets. However, if the IDs do not ever change
+ * for the packet stream it is recommended they are set using this function.
+ * In this case they can be omitted when sending packets to the stream.
+ * It is also possible to set only source or destination ID.
*
***/
-SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx);
+bool silc_packet_set_ids(SilcPacketStream stream,
+ SilcIdType src_id_type, const void *src_id,
+ SilcIdType dst_id_type, const void *dst_id);
-/****f* silccore/SilcPacketAPI/silc_packet_context_alloc
+/****f* silccore/SilcPacketAPI/silc_packet_send
*
* SYNOPSIS
*
- * SilcPacketContext *silc_packet_context_alloc();
+ * bool silc_packet_send(SilcPacketStream stream,
+ * SilcPacketType type, SilcPacketFlags flags,
+ * const unsigned char *data, SilcUInt32 data_len);
*
* DESCRIPTION
*
- * Allocates a packet context. Packet contexts are used when
- * packets are assembled and parsed. The context is freed by the
- * silc_packet_context_free function.
+ * Send `data' of length of `data_len' to the packet stream indicated by
+ * `stream'. If ciphers and HMACs were set using silc_packet_set_ciphers
+ * and silc_packet_set_hmacs the packet will be encrypted and MAC will be
+ * generated for it. If silc_packet_set_ids was used to set source and
+ * destination ID for the packet stream those IDs are used in the
+ * packet. If IDs have not been set and they need to be provided then
+ * silc_packet_send_ext function should be used. Otherwise, the packet
+ * will not have IDs set at all.
*
***/
-SilcPacketContext *silc_packet_context_alloc();
+bool silc_packet_send(SilcPacketStream stream,
+ SilcPacketType type, SilcPacketFlags flags,
+ const unsigned char *data, SilcUInt32 data_len);
-/****f* silccore/SilcPacketAPI/silc_packet_context_dup
+/****f* silccore/SilcPacketAPI/silc_packet_send_ext
*
* SYNOPSIS
*
- * SilcPacketContext *silc_packet_context_dup(SilcPacketContext *ctx);
+ * bool
+ * silc_packet_send_ext(SilcPacketStream stream,
+ * SilcPacketType type, SilcPacketFlags flags,
+ * SilcIdType src_id_type, void *srd_id,
+ * SilcIdType dst_id_type, void *dst_id,
+ * const unsigned char *data, SilcUInt32 data_len,
+ * SilcCipher cipher, SilcHmac hmac);
*
* DESCRIPTION
*
- * Duplicates the packet context. It actually does not duplicate
- * any data, instead a reference counter is increased.
+ * This function can be used to specificly set different parameters of
+ * the SILC packet to be sent to the stream indicated by `stream'. This
+ * function can be used to set specific IDs, cipher and HMAC to be used
+ * in packet creation. If `truelen' is provided that value is put to the
+ * SILC packet's truelen field, if it is zero the routine will calculate
+ * the truelen field for the packet. If `padlen' is provided that value
+ * will be the length of the padding for the packet, if zero the routine
+ * will calculate necessary amount of padding for the packet. This
+ * function can be used when specific ciphers, HMACs and IDs has not been
+ * set for the stream, or setting them for the stream is not suitable.
*
***/
-SilcPacketContext *silc_packet_context_dup(SilcPacketContext *ctx);
+bool silc_packet_send_ext(SilcPacketStream stream,
+ SilcPacketType type, SilcPacketFlags flags,
+ SilcIdType src_id_type, void *src_id,
+ SilcIdType dst_id_type, void *dst_id,
+ const unsigned char *data, SilcUInt32 data_len,
+ SilcCipher cipher, SilcHmac hmac);
-/****f* silccore/SilcPacketAPI/silc_packet_context_free
+/****f* silccore/SilcPacketAPI/silc_packet_free
*
* SYNOPSIS
*
- * void silc_packet_context_free(SilcPacketContext *ctx);
+ * void silc_packet_free(SilcPacketEngine engine, SilcPacket packet);
*
* DESCRIPTION
*
- * Frees the packet context. The context is actually freed when the
- * reference counter hits zero.
+ * This function is used to free the SilcPacket pointer that application
+ * receives in the SilcPacketReceive callback. Application must free
+ * the packet.
*
***/
-void silc_packet_context_free(SilcPacketContext *ctx);
+void silc_packet_free(SilcPacketEngine engine, SilcPacket packet);
-#endif
+#endif /* SILCPACKET_H */
projects / silc.git / blobdiff