X-Git-Url: http://git.silcnet.org/gitweb/?p=silc.git;a=blobdiff_plain;f=lib%2Fsilccore%2Fsilcpacket.h;h=1d0338f74fb50456f4548d6fc7904adac4f0734c;hp=d48035135b9302e90420f917de7085cfb50dc0d1;hb=e5d8d3db6caa344b3d419b884556c21b15e7d123;hpb=8ff83b6b8bc8479087038a285fc229862deb594c diff --git a/lib/silccore/silcpacket.h b/lib/silccore/silcpacket.h index d4803513..1d0338f7 100644 --- a/lib/silccore/silcpacket.h +++ b/lib/silccore/silcpacket.h @@ -1,16 +1,16 @@ /* silcpacket.h - - Author: Pekka Riikonen - - Copyright (C) 1997 - 2000 Pekka Riikonen - + + Author: Pekka Riikonen + + 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 @@ -18,15 +18,22 @@ */ +/****h* silccore/SilcPacketAPI + * + * DESCRIPTION + * + * Implementation of the packet routines for sending and receiving + * SILC Packets. These includes the data sending routines and data + * reading routines, encrypting and decrypting routines, packet assembling + * and packet parsing routines. + * + ***/ + #ifndef SILCPACKET_H #define SILCPACKET_H -/* Amount of bytes to be read from the socket connection at once. */ -#define SILC_PACKET_READ_SIZE 16384 - -/* 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 +/* Default byte size of the packet. */ +#define SILC_PACKET_DEFAULT_SIZE SILC_SOCKET_BUF_SIZE /* Header length without source and destination ID's. */ #define SILC_PACKET_HEADER_LEN 8 + 2 @@ -45,203 +52,626 @@ /* Maximum length of ID */ #define SILC_PACKET_MAX_ID_LEN 16 -/* SILC packet type definition. For now, it is defined like this and I don't - expect it to change in any near future. If one byte as a packet type is - not enough we can, then, think something else. */ +/****d* silccore/SilcPacketAPI/SilcPacketType + * + * NAME + * + * typedef unsigned char SilcPacketType; + * + * DESCRIPTION + * + * SILC packet type definition and all the packet types. + * + * SOURCE + */ typedef unsigned char SilcPacketType; -/* SILC packet version type definition. */ +/* SILC Packet types. */ +#define SILC_PACKET_NONE 0 /* NULL, never sent */ +#define SILC_PACKET_DISCONNECT 1 /* Disconnection */ +#define SILC_PACKET_SUCCESS 2 /* Success */ +#define SILC_PACKET_FAILURE 3 /* Failure */ +#define SILC_PACKET_REJECT 4 /* Rejected */ +#define SILC_PACKET_NOTIFY 5 /* Notify message */ +#define SILC_PACKET_ERROR 6 /* Error message */ +#define SILC_PACKET_CHANNEL_MESSAGE 7 /* Message for channel */ +#define SILC_PACKET_CHANNEL_KEY 8 /* Key of the channel */ +#define SILC_PACKET_PRIVATE_MESSAGE 9 /* Private message */ +#define SILC_PACKET_PRIVATE_MESSAGE_KEY 10 /* Private message key*/ +#define SILC_PACKET_COMMAND 11 /* Command */ +#define SILC_PACKET_COMMAND_REPLY 12 /* Reply to a command */ +#define SILC_PACKET_KEY_EXCHANGE 13 /* Start of KE */ +#define SILC_PACKET_KEY_EXCHANGE_1 14 /* KE1 */ +#define SILC_PACKET_KEY_EXCHANGE_2 15 /* KE2 */ +#define SILC_PACKET_CONNECTION_AUTH_REQUEST 16 /* Request of auth meth */ +#define SILC_PACKET_CONNECTION_AUTH 17 /* Connectinon auth */ +#define SILC_PACKET_NEW_ID 18 /* Sending new ID */ +#define SILC_PACKET_NEW_CLIENT 19 /* Client registering */ +#define SILC_PACKET_NEW_SERVER 20 /* Server registering */ +#define SILC_PACKET_NEW_CHANNEL 21 /* Channel registering */ +#define SILC_PACKET_REKEY 22 /* Re-key start */ +#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_RESUME_ROUTER 26 /* Backup router resume */ +#define SILC_PACKET_FTP 27 /* File Transfer */ + +#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; -/* SILC packet flags type definition. */ +/****d* silccore/SilcPacketAPI/SilcPacketFlags + * + * NAME + * + * typedef unsigned char SilcPacketFlags; + * + * DESCRIPTION + * + * SILC packet flags type definition and all the packet flags. + * + * SOURCE + */ typedef unsigned char SilcPacketFlags; /* All defined packet flags */ -#define SILC_PACKET_FLAG_NONE 0x00 -#define SILC_PACKET_FLAG_PRIVMSG_KEY 0x01 -#define SILC_PACKET_FLAG_FORWARDED 0x02 -#define SILC_PACKET_FLAG_BROADCAST 0x04 -#define SILC_PACKET_FLAG_TUNNELED 0x08 +#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 */ +/***/ + /* 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 */ -/* - SILC packet context. - - 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: - - SilcBuffer buffer - - The data buffer. - - SilcPacketType type - - Type of the packet. Types are defined below. - - SilcPacketFlags flags - - Packet flags. Flags are defined above. - - unsigned char *src_id - unsigned int src_id_len - SilcIdType src_id_type - - Source ID, its length and type. On packet reception retuned ID's - are always the hash values of the ID's from the packet. - - SilcHash hash - - Pointer to allocated hash object. This must be MD5 hash object. - This is used to calculate checksum of the packet. - -*/ +/****s* silccore/SilcPacketAPI/SilcPacketContext + * + * 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: + * + * SilcBuffer buffer + * + * The data buffer. + * + * SilcPacketType type + * + * Type of the packet. Types are defined below. + * + * SilcPacketFlags flags + * + * Packet flags. Flags are defined above. + * + * unsigned char *src_id + * uint16 src_id_len + * unsigned char src_id_type + * + * Source ID, its length and type. On packet reception retuned ID's + * are always the hash values of the ID's from the packet. + * + * unsigned char *dst_id; + * uint16 dst_id_len; + * unsigned char src_id_type; + * + * Destination ID, its length and type. On packet reception retuned + * ID's are always the hash values of the ID's from the packet. + * + * uint16 truelen + * uint16 padlen + * + * 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. + * + * int users; + * + * 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. + * + * uint32 sequence; + * + * Packet sequence number. + * + ***/ typedef struct { SilcBuffer buffer; SilcPacketType type; SilcPacketFlags flags; unsigned char *src_id; - unsigned int src_id_len; - SilcIdType src_id_type; + uint16 src_id_len; + unsigned char src_id_type; unsigned char *dst_id; - unsigned int dst_id_len; - SilcIdType dst_id_type; - - unsigned int truelen; - unsigned int padlen; - - /* For padding generation */ - SilcRng rng; -} SilcPacketContext; + uint16 dst_id_len; + unsigned char dst_id_type; -/* - Silc Packet Parser context. + uint16 truelen; + uint16 padlen; - 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. - - Following description of the fields: - - SilcPacketContext *packet - - 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. - - SilcSocketConnection sock - - The associated connection. - - SilcCipher cipher - - The cipher to be used in the decryption. - - SilcHmac hmac - - The HMAC to be used in the decryption. - - void *context + /* Back pointers */ + void *context; + SilcSocketConnection sock; - User context that is sent to the silc_packet_receive_process - function. This usually includes application and connection specific - data. + int users; -*/ + uint32 sequence; +} SilcPacketContext; +/****s* silccore/SilcPacketAPI/SilcPacketParserContext + * + * 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. + * + * Following description of the fields: + * + * SilcPacketContext *packet + * + * 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. + * + * SilcSocketConnection sock + * + * The associated connection. + * + * void *context + * + * User context that is sent to the silc_packet_receive_process + * function. This usually includes application and connection specific + * data. + * + ***/ typedef struct { SilcPacketContext *packet; SilcSocketConnection sock; - SilcCipher cipher; - SilcHmac hmac; void *context; } SilcPacketParserContext; -/* The parser callback function. */ +/****f* silccore/SilcPacketAPI/SilcPacketParserCallback + * + * SYNOPSIS + * + * typedef void (*SilcPacketParserCallback)(SilcPacketParserContext + * *parse_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. + * + ***/ typedef void (*SilcPacketParserCallback)(SilcPacketParserContext *parse_context); - -/* SILC Packet types. */ -#define SILC_PACKET_NONE 0 /* NULL, never sent */ -#define SILC_PACKET_DISCONNECT 1 /* Disconnection */ -#define SILC_PACKET_SUCCESS 2 /* Success */ -#define SILC_PACKET_FAILURE 3 /* Failure */ -#define SILC_PACKET_REJECT 4 /* Rejected */ -#define SILC_PACKET_NOTIFY 5 /* Notify message */ -#define SILC_PACKET_ERROR 6 /* Error message */ -#define SILC_PACKET_CHANNEL_MESSAGE 7 /* Message for channel */ -#define SILC_PACKET_CHANNEL_KEY 8 /* Key of the channel */ -#define SILC_PACKET_PRIVATE_MESSAGE 9 /* Private message */ -#define SILC_PACKET_PRIVATE_MESSAGE_KEY 10 /* Private message key*/ -#define SILC_PACKET_COMMAND 11 /* Command */ -#define SILC_PACKET_COMMAND_REPLY 12 /* Reply to a command */ -#define SILC_PACKET_KEY_EXCHANGE 13 /* Start of KE */ -#define SILC_PACKET_KEY_EXCHANGE_1 14 /* KE1 */ -#define SILC_PACKET_KEY_EXCHANGE_2 15 /* KE2 */ -#define SILC_PACKET_CONNECTION_AUTH_REQUEST 16 /* Request of auth meth */ -#define SILC_PACKET_CONNECTION_AUTH 17 /* Connectinon auth */ -#define SILC_PACKET_NEW_ID 18 /* Sending new ID */ -#define SILC_PACKET_NEW_ID_LIST 19 /* Sending list of them */ -#define SILC_PACKET_NEW_CLIENT 20 /* Registering client */ -#define SILC_PACKET_NEW_SERVER 21 /* Registering server */ -#define SILC_PACKET_NEW_CHANNEL 22 /* Registering channel */ -#define SILC_PACKET_NEW_CHANNEL_USER 23 /* "" user on channel */ -#define SILC_PACKET_NEW_CHANNEL_LIST 24 /* List of new channels */ -#define SILC_PACKET_NEW_CHANNEL_USER_LIST 25 /* List of users on "" */ -#define SILC_PACKET_REPLACE_ID 26 /* To replace old ID */ -#define SILC_PACKET_REMOVE_ID 27 /* To remove ID */ -#define SILC_PACKET_REMOVE_CHANNEL_USER 28 /* Remove user from channel */ -#define SILC_PACKET_REKEY 29 -#define SILC_PACKET_REKEY_DONE 30 -/* #define SILC_PACKET_MAX 255 */ +/****f* silccore/SilcPacketAPI/SilcPacketCheckDecrypt + * + * SYNOPSIS + * + * typedef int (*SilcPacketCheckDecrypt)(SilcPacketType packet_type, + * SilcBuffer buffer, + * SilcPacketContext *packet, + * void *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. + * + ***/ +typedef int (*SilcPacketCheckDecrypt)(SilcPacketType packet_type, + SilcBuffer buffer, + SilcPacketContext *packet, + void *context); /* Macros */ -/* Returns true length of the packet and padded length of the packet */ +/****d* silccore/SilcPacketAPI/SILC_PACKET_LENGTH + * + * NAME + * + * #define SILC_PACKET_LENGTH ... + * + * 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. + * + * 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) - -/* Returns pad length of the packet */ +/***/ + +/****d* silccore/SilcPacketAPI/SILC_PACKET_PADLEN + * + * NAME + * + * #define SILC_PACKET_PADLEN ... + * + * DESCRIPTION + * + * Returns the length of the padding in the packet. This is used + * by various library routines to determine needed padding length. + * + * SOURCE + */ #define SILC_PACKET_PADLEN(__packetlen) \ SILC_PACKET_MAX_PADLEN - ((__packetlen) - 2) % SILC_PACKET_MAX_PADLEN; +/***/ /* Prototypes */ + +/****f* silccore/SilcPacketAPI/silc_packet_write + * + * SYNOPSIS + * + * int silc_packet_write(int sock, SilcBuffer src); + * + * 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. + * + ***/ int silc_packet_write(int sock, SilcBuffer src); + +/****f* silccore/SilcPacketAPI/silc_packet_send + * + * SYNOPSIS + * + * int silc_packet_send(SilcSocketConnection sock, int force_send); + * + * 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. + * + ***/ int silc_packet_send(SilcSocketConnection sock, int force_send); + +/****f* silccore/SilcPacketAPI/silc_packet_encrypt + * + * SYNOPSIS + * + * void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac, + * SilcBuffer buffer, uint32 len); + * + * 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. + * + ***/ void silc_packet_encrypt(SilcCipher cipher, SilcHmac hmac, - SilcBuffer buffer, unsigned int len); + SilcBuffer buffer, uint32 len); + +/****f* silccore/SilcPacketAPI/silc_packet_assemble + * + * SYNOPSIS + * + * void silc_packet_assemble(SilcPacketContext *ctx); + * + * 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. + * + * The buffer sent as argument should be something like following: + * + * -------------------------------------------- + * | head | data | tail | + * -------------------------------------------- + * ^ ^ + * 58 bytes x bytes + * + * So that the SILC header and 1 - 16 bytes of padding can fit to + * the buffer. After assembly the buffer might look like this: + * + * -------------------------------------------- + * | data | | + * -------------------------------------------- + * ^ ^ + * Start of assembled packet + * + * Packet construct is as follows (* = won't be encrypted): + * + * 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 + * + * 1 - 16 bytes Padding + * + * n bytes Data payload + * + * 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. + * + ***/ void silc_packet_assemble(SilcPacketContext *ctx); + +/****f* silccore/SilcPacketAPI/silc_packet_send_prepare + * + * SYNOPSIS + * + * void silc_packet_send_prepare(SilcSocketConnection sock, + * uint32 header_len, + * uint32 padlen, + * uint32 data_len); + * + * 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. + * + ***/ void silc_packet_send_prepare(SilcSocketConnection sock, - unsigned int header_len, - unsigned int padlen, - unsigned int data_len); -int silc_packet_read(int sock, SilcBuffer dest); + uint32 header_len, + uint32 padlen, + uint32 data_len); + +/****f* silccore/SilcPacketAPI/silc_packet_read + * + * SYNOPSIS + * + * int silc_packet_read(int fd, SilcSocketConnection sock); + * + * 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. + * + * 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. + * + * 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. + * + ***/ +int silc_packet_read(int fd, SilcSocketConnection sock); + +/****f* silccore/SilcPacketAPI/silc_packet_receive + * + * SYNOPSIS + * + * int silc_packet_receive(SilcSocketConnection sock); + * + * 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. + * + ***/ int silc_packet_receive(SilcSocketConnection sock); + +/****f* silccore/SilcPacketAPI/silc_packet_decrypt + * + * SYNOPSIS + * + * int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac, + * SilcBuffer buffer, SilcPacketContext *packet, + * SilcPacketCheckDecrypt check_packet, + * void *context); + * + * 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. + * + * 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. + * + ***/ int silc_packet_decrypt(SilcCipher cipher, SilcHmac hmac, - SilcBuffer buffer, SilcPacketContext *packet); -int silc_packet_receive_process(SilcSocketConnection sock, - SilcCipher cipher, SilcHmac hmac, - SilcPacketParserCallback parser, - void *context); + SilcBuffer buffer, SilcPacketContext *packet, + SilcPacketCheckDecrypt check_packet, + void *context); + +/****f* silccore/SilcPacketAPI/silc_packet_receive_process + * + * SYNOPSIS + * + * void silc_packet_receive_process(SilcSocketConnection sock, + * SilcCipher cipher, SilcHmac hmac, + * SilcPacketParserCallback parser, + * void *context); + * + * 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. + * + ***/ +void silc_packet_receive_process(SilcSocketConnection sock, + SilcCipher cipher, SilcHmac hmac, + SilcPacketParserCallback parser, + void *context); + +/****f* silccore/SilcPacketAPI/silc_packet_parse + * + * SYNOPSIS + * + * SilcPacketType silc_packet_parse(SilcPacketContext *ctx); + * + * 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. + * + ***/ SilcPacketType silc_packet_parse(SilcPacketContext *ctx); + +/****f* silccore/SilcPacketAPI/silc_packet_parse_special + * + * SYNOPSIS + * + * SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx); + * + * 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. + * + ***/ SilcPacketType silc_packet_parse_special(SilcPacketContext *ctx); +/****f* silccore/SilcPacketAPI/silc_packet_context_alloc + * + * SYNOPSIS + * + * SilcPacketContext *silc_packet_context_alloc(); + * + * 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. + * + ***/ +SilcPacketContext *silc_packet_context_alloc(); + +/****f* silccore/SilcPacketAPI/silc_packet_context_dup + * + * SYNOPSIS + * + * SilcPacketContext *silc_packet_context_dup(SilcPacketContext *ctx); + * + * DESCRIPTION + * + * Duplicates the packet context. It actually does not duplicate + * any data, instead a reference counter is increased. + * + ***/ +SilcPacketContext *silc_packet_context_dup(SilcPacketContext *ctx); + +/****f* silccore/SilcPacketAPI/silc_packet_context_free + * + * SYNOPSIS + * + * void silc_packet_context_free(SilcPacketContext *ctx); + * + * DESCRIPTION + * + * Frees the packet context. The context is actually freed when the + * reference counter hits zero. + * + ***/ +void silc_packet_context_free(SilcPacketContext *ctx); + #endif