TLA  Line data    Source code

       1                 : /*-------------------------------------------------------------------------
       2                 :  *
       3                 :  * getpeereid.c
       4                 :  *      get peer userid for UNIX-domain socket connection
       5                 :  *
       6                 :  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
       7                 :  *
       8                 :  *
       9                 :  * IDENTIFICATION
      10                 :  *    src/port/getpeereid.c
      11                 :  *
      12                 :  *-------------------------------------------------------------------------
      13                 :  */
      14                 : 
      15                 : #include "c.h"
      16                 : 
      17                 : #include <sys/param.h>
      18                 : #include <sys/socket.h>
      19                 : #include <sys/un.h>
      20                 : #include <unistd.h>
      21                 : #ifdef HAVE_UCRED_H
      22                 : #include <ucred.h>
      23                 : #endif
      24                 : #ifdef HAVE_SYS_UCRED_H
      25                 : #include <sys/ucred.h>
      26                 : #endif
      27                 : 
      28                 : 
      29                 : /*
      30                 :  * BSD-style getpeereid() for platforms that lack it.
      31 ECB             :  */
      32                 : int
      33 GIC          27 : getpeereid(int sock, uid_t *uid, gid_t *gid)
      34                 : {
      35                 : #if defined(SO_PEERCRED)
      36 ECB             :     /* Linux: use getsockopt(SO_PEERCRED) */
      37                 :     struct ucred peercred;
      38 CBC          27 :     socklen_t   so_len = sizeof(peercred);
      39 ECB             : 
      40 GBC          27 :     if (getsockopt(sock, SOL_SOCKET, SO_PEERCRED, &peercred, &so_len) != 0 ||
      41 CBC          27 :         so_len != sizeof(peercred))
      42 LBC           0 :         return -1;
      43 CBC          27 :     *uid = peercred.uid;
      44 GIC          27 :     *gid = peercred.gid;
      45              27 :     return 0;
      46                 : #elif defined(LOCAL_PEERCRED)
      47                 :     /* Debian with FreeBSD kernel: use getsockopt(LOCAL_PEERCRED) */
      48                 :     struct xucred peercred;
      49                 :     socklen_t   so_len = sizeof(peercred);
      50                 : 
      51                 :     if (getsockopt(sock, 0, LOCAL_PEERCRED, &peercred, &so_len) != 0 ||
      52                 :         so_len != sizeof(peercred) ||
      53                 :         peercred.cr_version != XUCRED_VERSION)
      54                 :         return -1;
      55                 :     *uid = peercred.cr_uid;
      56                 :     *gid = peercred.cr_gid;
      57                 :     return 0;
      58                 : #elif defined(HAVE_GETPEERUCRED)
      59                 :     /* Solaris: use getpeerucred() */
      60                 :     ucred_t    *ucred;
      61                 : 
      62                 :     ucred = NULL;               /* must be initialized to NULL */
      63                 :     if (getpeerucred(sock, &ucred) == -1)
      64                 :         return -1;
      65                 : 
      66                 :     *uid = ucred_geteuid(ucred);
      67                 :     *gid = ucred_getegid(ucred);
      68                 :     ucred_free(ucred);
      69                 : 
      70                 :     if (*uid == (uid_t) (-1) || *gid == (gid_t) (-1))
      71                 :         return -1;
      72                 :     return 0;
      73                 : #else
      74                 :     /* No implementation available on this platform */
      75                 :     errno = ENOSYS;
      76                 :     return -1;
      77                 : #endif
      78                 : }