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/*
** Copyright 1998 - 2002 Double Precision, Inc. See COPYING for
** distribution information.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <grp.h>
#include <pwd.h>
#include <errno.h>
#include "numlib.h"
void libmail_changegroup(gid_t gid)
{
if ( setgid(gid))
{
perror("setgid");
exit(1);
}
#if HAVE_SETGROUPS
if ( getuid() == 0 && setgroups(1, &gid) )
{
perror("setgroups");
exit(1);
}
#endif
}
void libmail_changeuidgid(uid_t uid, gid_t gid)
{
libmail_changegroup(gid);
if ( setuid(uid))
{
perror("setuid");
exit(1);
}
}
/**
* Obtain the uid associated to uname and, optionally, the user primary gid
*/
uid_t libmail_getuid(const char *uname, gid_t *pw_gid)
{
size_t bufsize;
char *buf;
struct passwd pwbuf;
struct passwd *pw;
/*
** uname might be a pointer returned from a previous called to getpw(),
** and libc has a problem getting it back.
*/
char *p=malloc(strlen(uname)+1);
if (!p)
{
perror("malloc");
exit(1);
}
strcpy(p, uname);
#ifdef _SC_GETGR_R_SIZE_MAX
bufsize = sysconf(_SC_GETGR_R_SIZE_MAX);
if (bufsize == -1) /* Value was indeterminate */
{
#endif
bufsize = 16384; /* Should be more than enough */
}
buf = malloc(bufsize);
if (buf == NULL)
{
perror("malloc");
exit(1);
}
errno=ENOENT;
getpwnam_r(p, &pwbuf, buf, bufsize, &pw);
free(buf);
if (pw == 0)
{
free(p);
perror("getpwnam");
exit(1);
}
free(p);
if ( pw_gid ) *pw_gid = pw->pw_gid;
return pw->pw_uid;
}
void libmail_changeusername(const char *uname, const gid_t *forcegrp)
{
uid_t changeuid;
gid_t changegid;
changeuid=libmail_getuid(uname, &changegid);
if ( forcegrp ) changegid= *forcegrp;
if ( setgid( changegid ))
{
perror("setgid");
exit(1);
}
#if HAVE_INITGROUPS
if ( getuid() == 0 && initgroups(uname, changegid) )
{
perror("initgroups");
exit(1);
}
#else
#if HAVE_SETGROUPS
if ( getuid() == 0 && setgroups(1, &changegid) )
{
perror("setgroups");
exit(1);
}
#endif
#endif
if (setuid(changeuid))
{
perror("setuid");
exit(1);
}
}
gid_t libmail_getgid(const char *gname)
{
gid_t g;
struct group grp;
struct group *result;
char *buf;
size_t bufsize;
int s;
char *p=malloc(strlen(gname)+1);
if (!p)
{
perror("malloc");
exit(1);
}
strcpy(p, gname);
#ifdef _SC_GETGR_R_SIZE_MAX
bufsize = sysconf(_SC_GETGR_R_SIZE_MAX);
if (bufsize == -1) /* Value was indeterminate */
#endif
{
bufsize = 16384; /* Should be more than enough */
}
buf = malloc(bufsize);
if (buf == NULL)
{
perror("malloc");
exit(1);
}
s = getgrnam_r(p, &grp, buf, bufsize, &result);
free(p);
if (result == NULL)
{
if (s == 0)
{
fprintf(stderr, "CRIT: Group %s not found\n", gname);
}
else
{
errno = s;
perror("getpwnam_r");
}
exit(1);
}
g = grp.gr_gid;
free(buf);
return g;
}
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