/* $Id$ * * This file is a part of Amp2p. Amp2p is Copyright 2004 Joseph * Curtis. jocurtis@gmail.com * * * Amp2p 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. * * Amp2p 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. * * You should have received a copy of the GNU General Public License * along with Amp2p; if not, write to the Free Software Foundation, * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* This file containeth all of the defines, global variables and * function prototypes for amp2p. The functions which are expected to * be in xmms-amp2p.c and winamp-amp2p.c are prototyped here. * * Any xmms or winamp specific stuff goes in xmms-amp2p.h and * winamp-amp2p.h respectivly. */ //#include #include #include #include /* The version of amp2p. */ #define VERSION "0.0.1" /* There are two modes of operation (damn you NAT), live node where * you can accept incoming connections on a port, and NAT mode where * you can't. The plan is to implement live node mode first because, * seriously how hard is it to forward a port on your NAT box. When * this works then the no port forwarding mode will be implemented. * This complicates things somewhat as you might imagine. */ /* Maximum number of nodes in the nodelist */ #define MAX_NODELIST 100 /* The default port to listen on for connections */ #define LISTEN_PORT 1337 /* Maximum number of threads that may be spawned to handle the * transferal of data from another node. Pretty much this is the max * number of transfers. Who wants to do over 100 transfers * simultaneously anyway? */ #define MAX_TRANSFER_THREADS 100 /* Maximum number of threads that may be spawned to handle the * forwarding of searches. This will probably not ever get very high. * I can't imagine any more than 5 threads being required for this. */ #define MAX_FORWARD_THREADS 10 #define MAX_REQUEST_HANDLERS 3 #define MAX_THREADS 1000 #define MAX_RESULTS 100 /* The maximum backlog for TCP connections */ #define MAX_DOWNLOADS 10 /* This value is the maximum amount of data to be sent in each data * packet. Search request packets and file request packets will be * considerably smaller than this though. Incidentally this value is * the MTU of ethernet minus the length of the UDP and IP headers. 576/548. */ #define PACK_SIZE 548 /* Size of the packet header in bytes. */ #define HEADER_SIZE 18 #define DATA_SIZE (PACK_SIZE - HEADER_SIZE) #define NODELIST ".nodelist" #define CHECKSUMS_FILE ".checksums" /* Number of microseconds to sleep between processing a chunk of data for md5 hashing. Keeps cpu utilisation slow and steady instead of spikey. Slows things down a tad though. */ #define HASH_WAIT 1 /* Maximum recent queries to remember */ #define MAX_RECENT 3 /* Message types */ #define QUERY 1 #define REQUEST 2 #define DATA 3 #define PING 4 #define PING_REPLY 5 #define QUERY_REPLY 6 /* The maximum number of sockets that may be open at any one time. */ #define MAX_SOCKETS 10 /* The buffer length for reading/writing */ #define BUFLEN 1024 #define CLIST 0 #define DLIST 1 /* Debug statements */ #define DEBUG /* Message data structure. */ struct msg { unsigned int origin; /* address of original querier/file requester */ unsigned int from; /* address of the sender of this message. redundant? */ unsigned int to; /* address of the node this message is to. */ short int type; /* message type, QUERY | REQUEST | DATA | PING | ... If type is 0 then this message is corrupted/invalid. */ int length; /* length of the data in bytes. */ char * data; /* The data of the message. No fixed size because I don't wan't to take up 1500 bytes of memory for each message even if it has no data. */ }; /* Messages are structured in this way. The first 18 bytes are the * message header and are organised in the following way: * * Byte No(s) | C Type | Represents * ------------------------------------- * 0 - 3 | int | origin * 4 - 7 | int | from * 8 - 11 | int | to * 12 - 13 | short | type * 14 - 17 | int | length * * All components of the header are always present nomatter what type * of message it is. If it is not a data message then length shall be * zero and data in the msg structure will be null. * * The next length bytes of the message are the data. There is no end * of message character(s) and thus the data can contain any bytes. * If length > PACK_SIZE then the message is invalid. * * Note that although messages are a character array they are not * strings and have no null terminator. I guess they could have one * after then end of the data but it would not be part of the data * because it would be after length. * * Also note that ALL addresses are stored in NETWORK (MSB first) byte * order. That is opposite of the default on my box so watch out! * Use ntohl() to convert it you wish. It shouldn't ever be needed * though since you can use inet_ntoa() to get a string representation * of the address if you need it. */ /* Node data structure. Contains all info this node knows about any other node. The nodelist is an array of these structures. */ struct node { unsigned int addr; int ping; }; struct file { char * name; char * title; unsigned int length; /* Decided to go with normal int despite the 4GB barrier. Large files are not what this app is about and it complicates things somewhat */ unsigned int offset; /* may or may not be appripriate but it is staying! */ unsigned char checksum[16]; //TODO: change to MD5_DIGEST_LENGTH }; /* This is here so I can pass both the socket of the TCP connection and the client address details to a create thread at once. */ struct data { int sock; struct sockaddr_in addr; }; /* Now that I think about it, I will just do this with a hashtable. */ struct file_list { struct file item; struct file_list * next; }; /* functions for this list (may be implemented later) */ struct file_list file_list_init(struct file); void file_list_append(struct file_list, struct file); void file_list_get(struct file_list, int); void file_list_clear(struct file_list); /* PROTOTYPES -- ADD MORE HERE!! */ char * i2d(unsigned int); unsigned int local_addr(void); void send_msg(struct msg); void listen_for_requests(void); void listen_for_data(void); struct msg rcv_msg(void); int inc_sindex(int); void handle_request(char *); void ping(unsigned int); /* Abstraction. Threads and XMMS/Winamp specific stuff all have * abstraction functions, prototyped here. They will refer to * different code depending on which module is linked in (xmms or * winamp). * * I am still not quite sure how this is going to work. */ int create_thread(void *, void *); void exit_thread(void); int search_playlist(char *, struct msg); void ui(void); void _send_msg(unsigned int, unsigned int, unsigned int, short int, int, char *); void send_query(unsigned int, char *); void query(char *); int list_append(struct file, int); int is_recent_query(struct msg); void initial(void); void end(void); void print_checksum(unsigned char *); void hash_playlist(void); char * checksum_str(unsigned char *); unsigned char * str_checksum(char *); unsigned char * md5_wait(char *, int); char * lower(char *); void download(struct file, int); struct file decode_file(unsigned char *); int encode_file(struct file, unsigned char **); void reverse_str(char[]); void update_download(int, float); int die(char *); static unsigned long sdbm(unsigned char *); static int equalkeys(void *, void *); ssize_t con_write(int fd, const void *buf, size_t count); ssize_t con_read(int fd, void *buf, size_t count);