1  /* Copyright (C) 1992-2023 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
      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)