1 a812ae4b 2004-12-27 devnull // delimited, authenticated, encrypted connection
 2 a812ae4b 2004-12-27 devnull enum{ Maxmsg=4096 };	// messages > Maxmsg bytes are truncated
 3 a812ae4b 2004-12-27 devnull typedef struct SConn SConn;
 4 a812ae4b 2004-12-27 devnull 
 5 a812ae4b 2004-12-27 devnull extern SConn* newSConn(int);	// arg is open file descriptor
 6 a812ae4b 2004-12-27 devnull struct SConn{
 7 a812ae4b 2004-12-27 devnull 	void *chan;
 8 a812ae4b 2004-12-27 devnull 	int secretlen;
 9 a812ae4b 2004-12-27 devnull 	int (*secret)(SConn*, uchar*, int);// 
10 a812ae4b 2004-12-27 devnull 	int (*read)(SConn*, uchar*, int); // <0 if error;  errmess in buffer
11 a812ae4b 2004-12-27 devnull 	int (*write)(SConn*, uchar*, int);
12 a812ae4b 2004-12-27 devnull 	void (*free)(SConn*);		// also closes file descriptor
13 a812ae4b 2004-12-27 devnull };
14 a812ae4b 2004-12-27 devnull // secret(s,b,dir) sets secret for digest, encrypt, using the secretlen
15 a812ae4b 2004-12-27 devnull //		bytes in b to form keys 	for the two directions;
16 a812ae4b 2004-12-27 devnull //	  set dir=0 in client, dir=1 in server
17 a812ae4b 2004-12-27 devnull 
18 a812ae4b 2004-12-27 devnull // error convention: write !message in-band
19 a812ae4b 2004-12-27 devnull extern void writerr(SConn*, char*);
20 a812ae4b 2004-12-27 devnull extern int readstr(SConn*, char*);  // call with buf of size Maxmsg+1
21 a812ae4b 2004-12-27 devnull 	// returns -1 upon error, with error message in buf
22 a812ae4b 2004-12-27 devnull 
23 a812ae4b 2004-12-27 devnull extern void *emalloc(ulong); /* dies on failure; clears memory */
24 a812ae4b 2004-12-27 devnull extern void *erealloc(void *, ulong);
25 a812ae4b 2004-12-27 devnull extern char *estrdup(char *);
26 a812ae4b 2004-12-27 devnull