1 /* Copyright (C) 1992-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <errno.h>
19 #include <string.h>
20 #include <sys/socket.h>
21 
22 #include <hurd.h>
23 #include <hurd/fd.h>
24 #include <hurd/socket.h>
25 
26 /* Put the address of the peer connected to socket FD into *ADDR
27    (which is *LEN bytes long), and its actual length into *LEN.  */
28 int
__getpeername(int fd,__SOCKADDR_ARG addrarg,socklen_t * len)29 __getpeername (int fd, __SOCKADDR_ARG addrarg, socklen_t *len)
30 {
31   error_t err;
32   mach_msg_type_number_t buflen = *len;
33   int type;
34   struct sockaddr *addr = addrarg.__sockaddr__;
35   char *buf = (char *) addr;
36   addr_port_t aport;
37 
38   if (err = HURD_DPORT_USE (fd, __socket_peername (port, &aport)))
39     return __hurd_dfail (fd, err);
40 
41   err = __socket_whatis_address (aport, &type, &buf, &buflen);
42   __mach_port_deallocate (__mach_task_self (), aport);
43 
44   if (err)
45     return __hurd_dfail (fd, err);
46 
47   if (*len > buflen)
48     *len = buflen;
49 
50   if (buf != (char *) addr)
51     {
52       memcpy (addr, buf, *len);
53       __vm_deallocate (__mach_task_self (), (vm_address_t) buf, buflen);
54     }
55 
56   const sa_family_t family = type;
57   if (*len > offsetof (struct sockaddr, sa_family))
58     {
59       if (*len < (char *) (&addr->sa_family + 1) - (char *) addr)
60 	memcpy (&addr->sa_family, &family,
61 		*len - offsetof (struct sockaddr, sa_family));
62       else
63 	addr->sa_family = family;
64     }
65 
66   return 0;
67 }
68 
69 weak_alias (__getpeername, getpeername)
70