shadow/lib/shadow.c

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/*
* Copyright 1989 - 1994, Julianne Frances Haugh
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Julianne F. Haugh nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <config.h>
/* Newer versions of Linux libc already have shadow support. */
#if defined(SHADOWPWD) && !defined(HAVE_GETSPNAM) /*{*/
#include "rcsid.h"
RCSID("$Id: shadow.c,v 1.7 2003/05/03 16:14:24 kloczek Exp $")
#include <sys/types.h>
#include "prototypes.h"
#include "defines.h"
#include <stdio.h>
#ifdef NDBM
#include <ndbm.h>
#include <fcntl.h>
DBM *sp_dbm;
int sp_dbm_mode = -1;
static int dbmopened;
static int dbmerror;
#endif
#ifdef USE_NIS
static int nis_used;
static int nis_ignore;
static enum { native, start, middle, native2 } nis_state;
static int nis_bound;
static char *nis_domain;
static char *nis_key;
static int nis_keylen;
static char *nis_val;
static int nis_vallen;
#define IS_NISCHAR(c) ((c)=='+')
#endif
static FILE *shadow;
static char spwbuf[BUFSIZ];
static struct spwd spwd;
#define FIELDS 9
#define OFIELDS 5
#ifdef USE_NIS
/*
* __setspNIS - turn on or off NIS searches
*/
void
__setspNIS(int flag)
{
nis_ignore = ! flag;
if (nis_ignore)
nis_used = 0;
}
/*
* bind_nis - bind to NIS server
*/
static int
bind_nis(void)
{
if (yp_get_default_domain (&nis_domain))
return -1;
nis_bound = 1;
return 0;
}
#endif
/*
* setspent - initialize access to shadow text and DBM files
*/
void
setspent(void)
{
if (shadow)
rewind(shadow);
else
shadow = fopen(SHADOW_FILE, "r");
#ifdef USE_NIS
nis_state = native;
#endif
/*
* Attempt to open the DBM files if they have never been opened
* and an error has never been returned.
*/
#ifdef NDBM
if (! dbmerror && ! dbmopened) {
int mode;
char dbmfiles[BUFSIZ];
strcpy (dbmfiles, SHADOW_PAG_FILE);
if (sp_dbm_mode == -1)
mode = O_RDWR;
else
mode = (sp_dbm_mode == O_RDWR) ? O_RDWR:O_RDONLY;
if (! (sp_dbm = dbm_open (SHADOW_FILE, mode, 0)))
dbmerror = 1;
else
dbmopened = 1;
}
#endif
}
/*
* endspent - terminate access to shadow text and DBM files
*/
void
endspent(void)
{
if (shadow)
(void) fclose (shadow);
shadow = (FILE *) 0;
#ifdef NDBM
if (dbmopened && sp_dbm) {
dbm_close (sp_dbm);
sp_dbm = 0;
}
dbmopened = 0;
dbmerror = 0;
#endif
}
/*
* my_sgetspent - convert string in shadow file format to (struct spwd *)
*/
static struct spwd *
my_sgetspent(const char *string)
{
char *fields[FIELDS];
char *cp;
char *cpp;
int i;
/*
* Copy string to local buffer. It has to be tokenized and we
* have to do that to our private copy.
*/
if (strlen(string) >= sizeof spwbuf)
return 0;
strcpy(spwbuf, string);
if ((cp = strrchr (spwbuf, '\n')))
*cp = '\0';
/*
* Tokenize the string into colon separated fields. Allow up to
* FIELDS different fields.
*/
for (cp = spwbuf, i = 0;*cp && i < FIELDS;i++) {
fields[i] = cp;
while (*cp && *cp != ':')
cp++;
if (*cp)
*cp++ = '\0';
}
if (i == (FIELDS-1))
fields[i++] = cp;
if ((cp && *cp) || (i != FIELDS && i != OFIELDS))
return 0;
/*
* Start populating the structure. The fields are all in
* static storage, as is the structure we pass back. If we
* ever see a name with '+' as the first character, we try
* to turn on NIS processing.
*/
spwd.sp_namp = fields[0];
#ifdef USE_NIS
if (IS_NISCHAR (fields[0][0]))
nis_used = 1;
#endif
spwd.sp_pwdp = fields[1];
/*
* Get the last changed date. For all of the integer fields,
* we check for proper format. It is an error to have an
* incorrectly formatted number, unless we are using NIS.
*/
if ((spwd.sp_lstchg = strtol (fields[2], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_lstchg = -1;
#else
return 0;
#endif
} else if (fields[2][0] == '\0')
spwd.sp_lstchg = -1;
/*
* Get the minimum period between password changes.
*/
if ((spwd.sp_min = strtol (fields[3], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_min = -1;
#else
return 0;
#endif
} else if (fields[3][0] == '\0')
spwd.sp_min = -1;
/*
* Get the maximum number of days a password is valid.
*/
if ((spwd.sp_max = strtol (fields[4], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_max = -1;
#else
return 0;
#endif
} else if (fields[4][0] == '\0')
spwd.sp_max = -1;
/*
* If there are only OFIELDS fields (this is a SVR3.2 /etc/shadow
* formatted file), initialize the other field members to -1.
*/
if (i == OFIELDS) {
spwd.sp_warn = spwd.sp_inact = spwd.sp_expire =
spwd.sp_flag = -1;
return &spwd;
}
/*
* Get the number of days of password expiry warning.
*/
if ((spwd.sp_warn = strtol (fields[5], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_warn = -1;
#else
return 0;
#endif
} else if (fields[5][0] == '\0')
spwd.sp_warn = -1;
/*
* Get the number of days of inactivity before an account is
* disabled.
*/
if ((spwd.sp_inact = strtol (fields[6], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_inact = -1;
#else
return 0;
#endif
} else if (fields[6][0] == '\0')
spwd.sp_inact = -1;
/*
* Get the number of days after the epoch before the account is
* set to expire.
*/
if ((spwd.sp_expire = strtol (fields[7], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_expire = -1;
#else
return 0;
#endif
} else if (fields[7][0] == '\0')
spwd.sp_expire = -1;
/*
* This field is reserved for future use. But it isn't supposed
* to have anything other than a valid integer in it.
*/
if ((spwd.sp_flag = strtol (fields[8], &cpp, 10)) == 0 && *cpp) {
#ifdef USE_NIS
if (! nis_used)
return 0;
else
spwd.sp_flag = -1;
#else
return 0;
#endif
} else if (fields[8][0] == '\0')
spwd.sp_flag = -1;
return (&spwd);
}
/*
* fgetspent - get an entry from a /etc/shadow formatted stream
*/
struct spwd *
fgetspent(FILE *fp)
{
char buf[BUFSIZ];
char *cp;
if (! fp)
return (0);
#ifdef USE_NIS
while (fgets (buf, sizeof buf, fp) != (char *) 0)
#else
if (fgets (buf, sizeof buf, fp) != (char *) 0)
#endif
{
if ((cp = strchr (buf, '\n')))
*cp = '\0';
#ifdef USE_NIS
if (nis_ignore && IS_NISCHAR (buf[0]))
continue;
#endif
return my_sgetspent(buf);
}
return 0;
}
/*
* getspent - get a (struct spwd *) from the current shadow file
*/
struct spwd *
getspent(void)
{
#ifdef USE_NIS
int nis_1_user = 0;
struct spwd *val;
char buf[BUFSIZ];
#endif
if (! shadow)
setspent ();
#ifdef USE_NIS
again:
/*
* See if we are reading from the local file.
*/
if (nis_state == native || nis_state == native2) {
/*
* Get the next entry from the shadow file. Return NULL
* right away if there is none.
*/
if (! (val = fgetspent (shadow)))
return 0;
/*
* If this entry began with a NIS escape character, we have
* to see if this is just a single user, or if the entire
* map is being asked for.
*/
if (IS_NISCHAR (val->sp_namp[0])) {
if (val->sp_namp[1])
nis_1_user = 1;
else
nis_state = start;
}
/*
* If this isn't a NIS user and this isn't an escape to go
* use a NIS map, it must be a regular local user.
*/
if (nis_1_user == 0 && nis_state != start)
return val;
/*
* If this is an escape to use an NIS map, switch over to
* that bunch of code.
*/
if (nis_state == start)
goto again;
/*
* NEEDSWORK. Here we substitute pieces-parts of this entry.
*/
return 0;
} else {
if (nis_bound == 0) {
if (bind_nis ()) {
nis_state = native2;
goto again;
}
}
if (nis_state == start) {
if (yp_first (nis_domain, "shadow.bynam", &nis_key,
&nis_keylen, &nis_val, &nis_vallen)) {
nis_state = native2;
goto again;
}
nis_state = middle;
} else if (nis_state == middle) {
if (yp_next (nis_domain, "shadow.bynam", nis_key,
nis_keylen, &nis_key, &nis_keylen,
&nis_val, &nis_vallen)) {
nis_state = native2;
goto again;
}
}
return my_sgetspent(nis_val);
}
#else
return (fgetspent (shadow));
#endif
}
/*
* getspnam - get a shadow entry by name
*/
struct spwd *
getspnam(const char *name)
{
struct spwd *sp;
#ifdef NDBM
datum key;
datum content;
#endif
#ifdef USE_NIS
char buf[BUFSIZ];
static char save_name[16];
int nis_disabled = 0;
#endif
setspent ();
#ifdef NDBM
/*
* If the DBM file are now open, create a key for this UID and
* try to fetch the entry from the database. A matching record
* will be unpacked into a static structure and returned to
* the user.
*/
if (dbmopened) {
key.dsize = strlen (name);
key.dptr = (char *) name;
content = dbm_fetch (sp_dbm, key);
if (content.dptr != 0) {
memcpy (spwbuf, content.dptr, content.dsize);
spw_unpack (spwbuf, content.dsize, &spwd);
endspent();
return &spwd;
}
}
#endif
#ifdef USE_NIS
/*
* Search the shadow.byname map for this user.
*/
if (! nis_ignore && ! nis_bound)
bind_nis ();
if (! nis_ignore && nis_bound) {
char *cp;
if (yp_match (nis_domain, "shadow.byname", name,
strlen (name), &nis_val, &nis_vallen) == 0) {
if (cp = strchr (nis_val, '\n'))
*cp = '\0';
nis_state = middle;
if ((sp = my_sgetspent(nis_val))) {
strcpy (save_name, sp->sp_namp);
nis_key = save_name;
nis_keylen = strlen (save_name);
}
endspent();
return sp;
} else
nis_state = native2;
}
#endif
#ifdef USE_NIS
/*
* NEEDSWORK -- this is a mess, and it is the same mess in the
* other three files. I can't just blindly turn off NIS because
* this might be the first pass through the local files. In
* that case, I never discover that NIS is present.
*/
if (nis_used) {
nis_ignore++;
nis_disabled++;
}
#endif
while ((sp = getspent ()) != (struct spwd *) 0) {
if (strcmp (name, sp->sp_namp) == 0)
break;
}
#ifdef USE_NIS
if (nis_disabled)
nis_ignore--;
#endif
endspent();
return (sp);
}
#else
extern int errno; /* warning: ANSI C forbids an empty source file */
#endif /*}*/