/* delimited, authenticated, encrypted connection */ enum{ Maxmsg = 4096, /* messages > Maxmsg bytes are truncated */ }; typedef struct SConn SConn; typedef struct{ void *chan; int secretlen; int (*secret)(SConn*, uchar*, int); int (*read)(SConn*, uchar*, int); /* <0 if error; errmess in buffer */ int (*write)(SConn*, uchar*, int); void (*free)(SConn*); /* also closes file descriptor */ }SConn; SConn *newSConn(int); /* arg is open file descriptor */ /* * secret(s,b,dir) sets secret for digest, encrypt, using the secretlen * bytes in b to form keys for the two directions; * set dir=0 in client, dir=1 in server */ /* error convention: write !message in-band */ void writerr(SConn*, char*); /* * returns -1 upon error, with error message in buf * call with buf of size Maxmsg+1 */ int readstr(SConn*, char*); void *emalloc(ulong); /* dies on failure; clears memory */ void *erealloc(void*, ulong); char *estrdup(char*);