1 /*
2  * include/cm.h
3  *
4  * Copyright 2002 by the Massachusetts Institute of Technology.
5  * All Rights Reserved.
6  *
7  * Export of this software from the United States of America may
8  *   require a specific license from the United States Government.
9  *   It is the responsibility of any person or organization contemplating
10  *   export to obtain such a license before exporting.
11  *
12  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
13  * distribute this software and its documentation for any purpose and
14  * without fee is hereby granted, provided that the above copyright
15  * notice appear in all copies and that both that copyright notice and
16  * this permission notice appear in supporting documentation, and that
17  * the name of M.I.T. not be used in advertising or publicity pertaining
18  * to distribution of the software without specific, written prior
19  * permission.  Furthermore if you modify this software you must label
20  * your software as modified software and not distribute it in such a
21  * fashion that it might be confused with the original M.I.T. software.
22  * M.I.T. makes no representations about the suitability of
23  * this software for any purpose.  It is provided "as is" without express
24  * or implied warranty.
25  */
26 
27 /* Since fd_set is large on some platforms (8K on AIX 5.2), this
28    probably shouldn't be allocated in automatic storage.  */
29 struct select_state {
30     int max, nfds;
31     fd_set rfds, wfds, xfds;
32     struct timeval end_time;	/* magic: tv_sec==0 => never time out */
33 };
34 
35 
36 /* Select state flags.  */
37 #define SSF_READ	0x01
38 #define SSF_WRITE	0x02
39 #define SSF_EXCEPTION	0x04
40 
41 
42 static const char *const state_strings[] = {
43     "INITIALIZING", "CONNECTING", "WRITING", "READING", "FAILED"
44 };
45 
46 
47 /* connection states */
48 enum conn_states { INITIALIZING, CONNECTING, WRITING, READING, FAILED };
49 struct incoming_krb5_message {
50     size_t bufsizebytes_read;
51     size_t bufsize;
52     char *buf;
53     char *pos;
54     unsigned char bufsizebytes[4];
55     size_t n_left;
56 };
57 struct conn_state {
58     SOCKET fd;
59     krb5_error_code err;
60     enum conn_states state;
61     unsigned int is_udp : 1;
62     int (*service)(struct conn_state *, struct select_state *, int);
63     struct addrinfo *addr;
64     struct {
65 	struct {
66 	    sg_buf sgbuf[2];
67 	    sg_buf *sgp;
68 	    int sg_count;
69 	    unsigned char msg_len_buf[4];
70 	} out;
71 	struct incoming_krb5_message in;
72     } x;
73 };
74 
75 struct sendto_callback_info {
76     int  (*pfn_callback) (struct conn_state *, void *, krb5_data *);
77     void (*pfn_cleanup)  (void *, krb5_data *);
78     void  *context;
79 };
80 
81 
82 krb5_error_code krb5int_cm_call_select (const struct select_state *,
83 					struct select_state *, int *);
84