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/* Copyright (C) 1997-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <rpc/rpc.h>
#include <shlib-compat.h>
#include <libc-diag.h>
#include "nsswitch.h"
#define OPSYS_LEN 4
#define MAXIPRINT (11) /* max length of printed integer */
static const char OPSYS[] = "unix";
int
user2netname (char netname[MAXNETNAMELEN + 1], const uid_t uid,
const char *domain)
{
char dfltdom[MAXNETNAMELEN + 1];
size_t i;
if (domain == NULL)
{
if (getdomainname (dfltdom, sizeof (dfltdom)) < 0)
return 0;
}
else
{
strncpy (dfltdom, domain, MAXNETNAMELEN);
dfltdom[MAXNETNAMELEN] = '\0';
}
if ((strlen (dfltdom) + OPSYS_LEN + 3 + MAXIPRINT) > (size_t) MAXNETNAMELEN)
return 0;
/* GCC with -Os warns that sprint might overflow while handling dfltdom,
however the above test does check if an overflow would happen. */
DIAG_PUSH_NEEDS_COMMENT;
DIAG_IGNORE_Os_NEEDS_COMMENT (8, "-Wformat-overflow");
sprintf (netname, "%s.%d@%s", OPSYS, uid, dfltdom);
DIAG_POP_NEEDS_COMMENT;
i = strlen (netname);
if (netname[i - 1] == '.')
netname[i - 1] = '\0';
return 1;
}
libc_hidden_nolink_sunrpc (user2netname, GLIBC_2_1)
int
host2netname (char netname[MAXNETNAMELEN + 1], const char *host,
const char *domain)
{
char *p;
char hostname[MAXHOSTNAMELEN + 1];
char domainname[MAXHOSTNAMELEN + 1];
char *dot_in_host;
size_t i;
netname[0] = '\0'; /* make null first (no need for memset) */
if (host == NULL)
__gethostname (hostname, MAXHOSTNAMELEN);
else
{
strncpy (hostname, host, MAXHOSTNAMELEN);
hostname[MAXHOSTNAMELEN] = '\0';
}
dot_in_host = strchr (hostname, '.');
if (domain == NULL)
{
p = dot_in_host;
if (p)
{
++p;
strncpy (domainname, p, MAXHOSTNAMELEN);
domainname[MAXHOSTNAMELEN] = '\0';
}
else
{
domainname[0] = 0;
getdomainname (domainname, MAXHOSTNAMELEN);
}
}
else
{
strncpy (domainname, domain, MAXHOSTNAMELEN);
domainname[MAXHOSTNAMELEN] = '\0';
}
i = strlen (domainname);
if (i == 0)
/* No domainname */
return 0;
if (domainname[i - 1] == '.')
domainname[i - 1] = 0;
if (dot_in_host) /* strip off rest of name */
*dot_in_host = '\0';
if ((strlen (domainname) + strlen (hostname) + OPSYS_LEN + 3)
> MAXNETNAMELEN)
return 0;
sprintf (netname, "%s.%s@%s", OPSYS, hostname, domainname);
return 1;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (host2netname)
#else
libc_hidden_nolink_sunrpc (host2netname, GLIBC_2_1)
#endif
int
getnetname (char name[MAXNETNAMELEN + 1])
{
uid_t uid;
int dummy;
uid = __geteuid ();
if (uid == 0)
dummy = host2netname (name, NULL, NULL);
else
dummy = user2netname (name, uid, NULL);
return (dummy);
}
libc_hidden_nolink_sunrpc (getnetname, GLIBC_2_1)
/* Type of the lookup function for netname2user. */
typedef int (*netname2user_function) (const char netname[MAXNETNAMELEN + 1],
uid_t *, gid_t *, int *, gid_t *);
int
netname2user (const char *netname, uid_t * uidp, gid_t * gidp,
int *gidlenp, gid_t * gidlist)
{
nss_action_list nip;
union
{
netname2user_function f;
void *ptr;
} fct;
enum nss_status status = NSS_STATUS_UNAVAIL;
int no_more;
no_more = __nss_publickey_lookup2 (&nip, "netname2user", NULL, &fct.ptr);
while (!no_more)
{
status = (*fct.f) (netname, uidp, gidp, gidlenp, gidlist);
no_more = __nss_next2 (&nip, "netname2user", NULL, &fct.ptr, status, 0);
}
return status == NSS_STATUS_SUCCESS;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (netname2user)
#else
libc_hidden_nolink_sunrpc (netname2user, GLIBC_2_1)
#endif
int
netname2host (const char *netname, char *hostname, const int hostlen)
{
char *p1, *p2;
p1 = strchr (netname, '.');
if (p1 == NULL)
return 0;
p1++;
p2 = strchr (p1, '@');
if (p2 == NULL)
return 0;
*p2 = '\0';
if (hostlen > MAXNETNAMELEN)
return 0;
strncpy (hostname, p1, hostlen);
hostname[hostlen] = '\0';
return 1;
}
libc_hidden_nolink_sunrpc (netname2host, GLIBC_2_1)
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