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/*
* Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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 the Institute 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 THE INSTITUTE 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 THE INSTITUTE 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.
*/
/* This code is extremely ugly, and would probably be better off
beeing completely rewritten */
#ifdef HAVE_CONFIG_H
#include<config.h>
RCSID("$Id: pam.c,v 1.22 1999/12/02 16:58:37 joda Exp $");
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pwd.h>
#include <unistd.h>
#include <sys/types.h>
#define PAM_SM_AUTH
#define PAM_SM_SESSION
#include <security/pam_appl.h>
#include <security/pam_modules.h>
#include <netinet/in.h>
#include <krb.h>
#include <kafs.h>
static int
cleanup(pam_handle_t *pamh, void *data, int error_code)
{
if(error_code != PAM_SUCCESS)
dest_tkt();
free(data);
return PAM_SUCCESS;
}
static int
doit(pam_handle_t *pamh, char *name, char *inst, char *pwd, char *tkt)
{
char realm[REALM_SZ];
int ret;
pam_set_data(pamh, "KRBTKFILE", strdup(tkt), cleanup);
krb_set_tkt_string(tkt);
krb_get_lrealm(realm, 1);
ret = krb_verify_user(name, inst, realm, pwd, KRB_VERIFY_SECURE, NULL);
memset(pwd, 0, strlen(pwd));
switch(ret){
case KSUCCESS:
return PAM_SUCCESS;
case KDC_PR_UNKNOWN:
return PAM_USER_UNKNOWN;
case SKDC_CANT:
case SKDC_RETRY:
case RD_AP_TIME:
return PAM_AUTHINFO_UNAVAIL;
default:
return PAM_AUTH_ERR;
}
}
static int
auth_login(pam_handle_t *pamh, int flags, char *user, struct pam_conv *conv)
{
int ret;
struct pam_message msg, *pmsg;
struct pam_response *resp;
char prompt[128];
pmsg = &msg;
msg.msg_style = PAM_PROMPT_ECHO_OFF;
snprintf(prompt, sizeof(prompt), "%s's Password: ", user);
msg.msg = prompt;
ret = conv->conv(1, (const struct pam_message**)&pmsg,
&resp, conv->appdata_ptr);
if(ret != PAM_SUCCESS)
return ret;
{
char tkt[1024];
struct passwd *pw = getpwnam(user);
if(pw){
snprintf(tkt, sizeof(tkt),
"%s%u", TKT_ROOT, (unsigned)pw->pw_uid);
ret = doit(pamh, user, "", resp->resp, tkt);
if(ret == PAM_SUCCESS)
chown(tkt, pw->pw_uid, pw->pw_gid);
}else
ret = PAM_USER_UNKNOWN;
memset(resp->resp, 0, strlen(resp->resp));
free(resp->resp);
free(resp);
}
return ret;
}
static int
auth_su(pam_handle_t *pamh, int flags, char *user, struct pam_conv *conv)
{
int ret;
struct passwd *pw;
struct pam_message msg, *pmsg;
struct pam_response *resp;
char prompt[128];
krb_principal pr;
pr.realm[0] = 0;
ret = pam_get_user(pamh, &user, "login: ");
if(ret != PAM_SUCCESS)
return ret;
pw = getpwuid(getuid());
if(strcmp(user, "root") == 0){
strlcpy(pr.name, pw->pw_name, sizeof(pr.name));
strlcpy(pr.instance, "root", sizeof(pr.instance));
}else{
strlcpy(pr.name, user, sizeof(pr.name));
pr.instance[0] = 0;
}
pmsg = &msg;
msg.msg_style = PAM_PROMPT_ECHO_OFF;
snprintf(prompt, sizeof(prompt), "%s's Password: ", krb_unparse_name(&pr));
msg.msg = prompt;
ret = conv->conv(1, (const struct pam_message**)&pmsg,
&resp, conv->appdata_ptr);
if(ret != PAM_SUCCESS)
return ret;
{
char tkt[1024];
snprintf(tkt, sizeof(tkt),"%s_%s_to_%s",
TKT_ROOT, pw->pw_name, user);
ret = doit(pamh, pr.name, pr.instance, resp->resp, tkt);
if(ret == PAM_SUCCESS)
chown(tkt, pw->pw_uid, pw->pw_gid);
memset(resp->resp, 0, strlen(resp->resp));
free(resp->resp);
free(resp);
}
return ret;
}
int
pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const char **argv)
{
char *user;
int ret;
struct pam_conv *conv;
ret = pam_get_user(pamh, &user, "login: ");
if(ret != PAM_SUCCESS)
return ret;
ret = pam_get_item(pamh, PAM_CONV, (void*)&conv);
if(ret != PAM_SUCCESS)
return ret;
if(getuid() != geteuid())
return auth_su(pamh, flags, user, conv);
else
return auth_login(pamh, flags, user, conv);
}
int
pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv)
{
return PAM_SUCCESS;
}
int
pam_sm_open_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
{
char *tkt, *var;
void *user;
const char *homedir = NULL;
if(pam_get_item (pamh, PAM_USER, &user) == PAM_SUCCESS) {
struct passwd *pwd;
pwd = getpwnam ((char *)user);
if (pwd != NULL)
homedir = pwd->pw_dir;
}
pam_get_data(pamh, "KRBTKFILE", (const void**)&tkt);
var = malloc(strlen("KRBTKFILE=") + strlen(tkt) + 1);
strcpy(var, "KRBTKFILE=");
strcat(var, tkt);
putenv(var);
pam_putenv(pamh, var);
if(k_hasafs()){
k_setpag();
krb_afslog_home(0, 0, homedir);
}
return PAM_SUCCESS;
}
int
pam_sm_close_session(pam_handle_t *pamh, int flags, int argc, const char **argv)
{
dest_tkt();
if(k_hasafs())
k_unlog();
return PAM_SUCCESS;
}
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