1 /*
2  * Copyright (c) 2010, Oracle America, Inc.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are
6  * met:
7  *
8  *     * Redistributions of source code must retain the above copyright
9  *       notice, this list of conditions and the following disclaimer.
10  *     * Redistributions in binary form must reproduce the above
11  *       copyright notice, this list of conditions and the following
12  *       disclaimer in the documentation and/or other materials
13  *       provided with the distribution.
14  *     * Neither the name of the "Oracle America, Inc." nor the names of its
15  *       contributors may be used to endorse or promote products derived
16  *       from this software without specific prior written permission.
17  *
18  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
25  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
28  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 /*
32  * rtime - get time from remote machine
33  *
34  * gets time, obtaining value from host
35  * on the udp/time socket.  Since timeserver returns
36  * with time of day in seconds since Jan 1, 1900,  must
37  * subtract seconds before Jan 1, 1970 to get
38  * what unix uses.
39  */
40 #include <stdio.h>
41 #include <unistd.h>
42 #include <stdint.h>
43 #include <rpc/rpc.h>
44 #include <rpc/clnt.h>
45 #include <sys/types.h>
46 #include <sys/poll.h>
47 #include <sys/socket.h>
48 #include <sys/time.h>
49 #include <rpc/auth_des.h>
50 #include <errno.h>
51 #include <netinet/in.h>
52 #include <shlib-compat.h>
53 
54 #define NYEARS	(u_long)(1970 - 1900)
55 #define TOFFSET (u_long)(60*60*24*(365*NYEARS + (NYEARS/4)))
56 
57 static void do_close (int);
58 
59 static void
do_close(int s)60 do_close (int s)
61 {
62   int save;
63 
64   save = errno;
65   __close (s);
66   __set_errno (save);
67 }
68 
69 int
rtime(struct sockaddr_in * addrp,struct rpc_timeval * timep,struct rpc_timeval * timeout)70 rtime (struct sockaddr_in *addrp, struct rpc_timeval *timep,
71        struct rpc_timeval *timeout)
72 {
73   int s;
74   struct pollfd fd;
75   int milliseconds;
76   int res;
77   /* RFC 868 says the time is transmitted as a 32-bit value.  */
78   uint32_t thetime;
79   struct sockaddr_in from;
80   socklen_t fromlen;
81   int type;
82 
83   if (timeout == NULL)
84     type = SOCK_STREAM;
85   else
86     type = SOCK_DGRAM;
87 
88   s = __socket (AF_INET, type, 0);
89   if (s < 0)
90     return (-1);
91 
92   addrp->sin_family = AF_INET;
93   addrp->sin_port = htons (IPPORT_TIMESERVER);
94   if (type == SOCK_DGRAM)
95     {
96       res = __sendto (s, (char *) &thetime, sizeof (thetime), 0,
97 		      (struct sockaddr *) addrp, sizeof (*addrp));
98       if (res < 0)
99 	{
100 	  do_close (s);
101 	  return -1;
102 	}
103       milliseconds = (timeout->tv_sec * 1000) + (timeout->tv_usec / 1000);
104       fd.fd = s;
105       fd.events = POLLIN;
106       do
107 	res = __poll (&fd, 1, milliseconds);
108       while (res < 0 && errno == EINTR);
109       if (res <= 0)
110 	{
111 	  if (res == 0)
112 	    __set_errno (ETIMEDOUT);
113 	  do_close (s);
114 	  return (-1);
115 	}
116       fromlen = sizeof (from);
117       res = __recvfrom (s, (char *) &thetime, sizeof (thetime), 0,
118 			(struct sockaddr *) &from, &fromlen);
119       do_close (s);
120       if (res < 0)
121 	return -1;
122     }
123   else
124     {
125       if (__connect (s, (struct sockaddr *) addrp, sizeof (*addrp)) < 0)
126 	{
127 	  do_close (s);
128 	  return -1;
129 	}
130       res = __read (s, (char *) &thetime, sizeof (thetime));
131       do_close (s);
132       if (res < 0)
133 	return (-1);
134     }
135   if (res != sizeof (thetime))
136     {
137       __set_errno (EIO);
138       return -1;
139     }
140   thetime = ntohl (thetime);
141   timep->tv_sec = thetime - TOFFSET;
142   timep->tv_usec = 0;
143   return 0;
144 }
145 libc_hidden_nolink_sunrpc (rtime, GLIBC_2_1)
146