summaryrefslogtreecommitdiff
path: root/libiohelp/iohelp.h
blob: 0597d6c77b23b787d18eb0e69c6ee21b431cd302 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/* Library providing helper functions for io servers.
   Copyright (C) 1993,94,96,98,2001,02 Free Software Foundation, Inc.

   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, 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 GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */

#ifndef _HURD_IOHELP_
#define _HURD_IOHELP_

#include <mach.h>
#include <hurd/hurd_types.h>
#include <pthread.h>
#include <hurd/shared.h>

/* Conch manipulation.  */
struct conch
{
  pthread_mutex_t *lock;
  pthread_cond_t wait;
  void *holder;
  struct shared_io *holder_shared_page;
};

/* Initialize a conch box */
void iohelp_initialize_conch (struct conch *, pthread_mutex_t *);

/* These routines are not reentrant.  The server is responsible
   for ensuring that all calls to these routines are serialized
   by locking the lock passed to initialize_conch. */

/* Handle a user request to obtain the conch (io_get_conch) */
void iohelp_handle_io_get_conch (struct conch *, void *,
				      struct shared_io *);

/* Obtain the conch for the server */
void iohelp_get_conch (struct conch *);

/* Handle a user request to release the conch (io_release_conch). */
void iohelp_handle_io_release_conch (struct conch *, void *);

/* Check if the user is allowed to make a shared-data notification
   message. */
error_t iohelp_verify_user_conch (struct conch *, void *);

/* This function must by defined by the server.  It should transfer
   information from the current conch holder's shared page to the server's
   data (the arg is the conch owner). */
void iohelp_fetch_shared_data (void *);

/* This function must be defined by the server.  It should transfer
   information from the server's data to the current conch holder's
   shared page (the arg is the conch owner). */
void iohelp_put_shared_data (void *);



/* User identification */

#include <idvec.h>

struct iouser
{
  struct idvec *uids, *gids;
  void *hook; /* Never used by iohelp library */
};

/* Return a copy of IOUSER in CLONE.  On error, *CLONE is set to NULL.  */
error_t iohelp_dup_iouser (struct iouser **clone, struct iouser *iouser);

/* Free a reference to IOUSER. */
void iohelp_free_iouser (struct iouser *iouser);

/* Create a new IOUSER in USER for the specified idvecs.  On error, *USER
   is set to NULL.  */
error_t iohelp_create_iouser (struct iouser **user, struct idvec *uids,
			      struct idvec *gids);

/* Create a new IOUSER in USER for the specified arrays.  On error, *USER
   is set to NULL.  */
error_t iohelp_create_complex_iouser (struct iouser **user,
				      const uid_t *uids, int nuids,
				      const gid_t *gids, int ngids);

/* Create a new IOUSER in USER for the specified uid and gid.  On error,
   *USER is set to NULL.  */
error_t iohelp_create_simple_iouser (struct iouser **user,
				     uid_t uid, gid_t gid);

/* Create a new IOUSER in USER with no identity.  On error, *USER is set
   to NULL.  */
error_t iohelp_create_empty_iouser (struct iouser **user);

/* Create a new IOUSER in NEW_USER that restricts OLD_USER to the subset
   specified by the two ID lists.  This is appropriate for implementing
   io_restrict_auth.  */
error_t iohelp_restrict_iouser (struct iouser **new_user,
				const struct iouser *old_user,
				const uid_t *uids, int nuids,
				const gid_t *gids, int ngids);

/* Conduct a reauthentication transaction, returning a new iouser in
   USER.  AUTHSERVER is the I/O servers auth port.  The rendezvous port
   provided by the user is REND_PORT.  If the transaction cannot be
   completed, return zero, unless PERMIT_FAILURE is non-zero.  If
   PERMIT_FAILURE is nonzero, then should the transaction fail, return
   an iouser that has no ids.  The new port to be sent to the user is
   newright.  On error, *USER is set to NULL.  */
error_t iohelp_reauth (struct iouser **user, auth_t authserver,
		       mach_port_t rend_port, mach_port_t newright,
		       int permit_failure);


/* Puts data from the malloced buffer BUF, LEN bytes long, into RBUF & RLEN,
   suitable for returning from a mach rpc.  If LEN > 0, BUF is freed,
   regardless of whether an error is returned or not.  */
error_t iohelp_return_malloced_buffer (char *buf, size_t len,
				       char **rbuf,
				       mach_msg_type_number_t *rlen);



#endif