xref: /freebsd/tools/regression/sockets/unix_cmsg/README (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
1$FreeBSD$
2
3About unix_cmsg
4===============
5
6This program is a collection of regression tests for ancillary data
7(control information) for PF_LOCAL sockets (local domain or Unix domain
8sockets).  There are tests for stream and datagram sockets.
9
10Usually each test does following steps: creates Server, forks Client,
11Client sends something to Server, Server verifies whether everything is
12correct in received message(s).
13
14It is better to change the owner of unix_cmsg to some safe user
15(eg. nobody:nogroup) and set SUID and SGID bits, else some tests that
16check credentials can give correct results for wrong implementation.
17
18It is better to run this program by a user that belongs to more
19than 16 groups.
20
21Available options
22=================
23
24usage: unix_cmsg [-dh] [-n num] [-s size] [-t type] [-z value] [testno]
25
26 Options are:
27  -d            Output debugging information
28  -h            Output the help message and exit
29  -n num        Number of messages to send
30  -s size       Specify size of data for IPC
31  -t type       Specify socket type (stream, dgram) for tests
32  -z value      Do not send data in a message (bit 0x1), do not send
33                data array associated with a cmsghdr structure (bit 0x2)
34  testno        Run one test by its number (require the -t option)
35
36Description
37===========
38
39If Client sends something to Server, then it sends 5 messages by default.
40Number of messages can be changed in the -n command line option.  Number
41of messages will be given as N in the following descriptions.
42
43If Client sends something to Server, then it sends some data (few bytes)
44in each message by default.  The size of this data can be changed by the -s
45command line option.  The "-s 0" command line option means, that Client will
46send zero bytes represented by { NULL, 0 } value of struct iovec{}, referenced
47by the msg_iov field from struct msghdr{}.  The "-z 1" or "-z 3" command line
48option means, that Client will send zero bytes represented by the NULL value
49in the msg_iov field from struct msghdr{}.
50
51If Client sends some ancillary data object, then this ancillary data object
52always has associated data array by default.  The "-z 2" or "-z 3" option
53means, that Client will not send associated data array if possible.
54
55For SOCK_STREAM sockets:
56-----------------------
57
58 1: Sending, receiving cmsgcred
59
60    Client connects to Server and sends N messages with SCM_CREDS ancillary
61    data object.  Server should receive N messages, each message should
62    have SCM_CREDS ancillary data object followed by struct cmsgcred{}.
63
64 2: Receiving sockcred (listening socket)
65
66    Server creates a listening stream socket and sets the LOCAL_CREDS
67    socket option for it.  Client connects to Server two times, each time
68    it sends N messages.  Server accepts two connections and receives N
69    messages from each connection.  The first message from each connection
70    should have SCM_CREDS ancillary data object followed by struct sockcred{},
71    next messages from the same connection should not have ancillary data.
72
73 3: Receiving sockcred (accepted socket)
74
75    Client connects to Server.  Server accepts connection and sets the
76    LOCAL_CREDS socket option for just accepted socket.  Client sends N
77    messages to Server.  Server should receive N messages, the first
78    message should have SCM_CREDS ancillary data object followed by
79    struct sockcred{}, next messages should not have ancillary data.
80
81 4: Sending cmsgcred, receiving sockcred
82
83    Server creates a listening stream socket and sets the LOCAL_CREDS
84    socket  option for it.  Client connects to Server and sends N messages
85    with SCM_CREDS ancillary data object.  Server should receive N messages,
86    the first message should have SCM_CREDS ancillary data object followed
87    by struct sockcred{}, each of next messages should have SCM_CREDS
88    ancillary data object followed by struct cmsgcred{}.
89
90 5: Sending, receiving timeval
91
92    Client connects to Server and sends message with SCM_TIMESTAMP ancillary
93    data object.  Server should receive one message with SCM_TIMESTAMP
94    ancillary data object followed by struct timeval{}.
95
96 6: Sending, receiving bintime
97
98    Client connects to Server and sends message with SCM_BINTIME ancillary
99    data object.  Server should receive one message with SCM_BINTIME
100    ancillary data object followed by struct bintime{}.
101
102 7: Checking cmsghdr.cmsg_len
103
104    Client connects to Server and tries to send several messages with
105    SCM_CREDS ancillary data object that has wrong cmsg_len field in its
106    struct cmsghdr{}.  All these attempts should fail, since cmsg_len
107    in all requests is less than CMSG_LEN(0).
108
109 8: Check LOCAL_PEERCRED socket option
110
111    This test does not use ancillary data, but can be implemented here.
112    Client connects to Server.  Both Client and Server verify that
113    credentials of the peer are correct using LOCAL_PEERCRED socket option.
114
115For SOCK_DGRAM sockets:
116----------------------
117
118 1: Sending, receiving cmsgcred
119
120    Client connects to Server and sends N messages with SCM_CREDS ancillary
121    data object.  Server should receive N messages, each message should
122    have SCM_CREDS ancillary data object followed by struct cmsgcred{}.
123
124 2: Receiving sockcred
125
126    Server creates datagram socket and sets the LOCAL_CREDS socket option
127    for it.  Client sends N messages to Server.  Server should receive N
128    messages, each message should have SCM_CREDS ancillary data object
129    followed by struct sockcred{}.
130
131 3: Sending cmsgcred, receiving sockcred
132
133    Server creates datagram socket and sets the LOCAL_CREDS socket option
134    for it.  Client sends N messages with SCM_CREDS ancillary data object
135    to Server.  Server should receive N messages, the first message should
136    have SCM_CREDS ancillary data object followed by struct sockcred{},
137    each of next messages should have SCM_CREDS ancillary data object
138    followed by struct cmsgcred{}.
139
140 4: Sending, receiving timeval
141
142    Client sends one message with SCM_TIMESTAMP ancillary data object
143    to Server.  Server should receive one message with SCM_TIMESTAMP
144    ancillary data object followed by struct timeval{}.
145
146 5: Sending, receiving bintime
147
148    Client sends one message with SCM_BINTIME ancillary data object
149    to Server.  Server should receive one message with SCM_BINTIME
150    ancillary data object followed by struct bintime{}.
151
152 6: Checking cmsghdr.cmsg_len
153
154    Client tries to send Server several messages with SCM_CREDS ancillary
155    data object that has wrong cmsg_len field in its struct cmsghdr{}.
156    All these attempts should fail, since cmsg_len in all requests is less
157    than CMSG_LEN(0).
158
159- Andrey Simonenko
160andreysimonenko@users.sourceforge.net
161