/*
Authors:
Sumit Bose <sbose@redhat.com>
Copyright (C) 2009 Red Hat
Copyright (C) 2010, rhafer@suse.de, Novell Inc.
This program 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 3 of the License, or
(at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
#define PAM_SM_AUTH
#define PAM_SM_ACCOUNT
#define PAM_SM_SESSION
#define PAM_SM_PASSWORD
#include "config.h"
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <syslog.h>
#include <time.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <locale.h>
#include <stdbool.h>
#include <security/pam_modules.h>
#include <security/pam_ext.h>
#include <security/pam_modutil.h>
#include "sss_pam_macros.h"
#include "sss_cli.h"
#include <libintl.h>
#define _(STRING) dgettext (PACKAGE, STRING)
#define FLAGS_USE_FIRST_PASS (1 << 0)
#define FLAGS_FORWARD_PASS (1 << 1)
#define FLAGS_USE_AUTHTOK (1 << 2)
#define PWEXP_FLAG "pam_sss:password_expired_flag"
#define PW_RESET_MSG_FILENAME_TEMPLATE SSSD_CONF_DIR"/customize/%s/pam_sss_pw_reset_message.%s"
#define PW_RESET_MSG_MAX_SIZE 4096
#define OPT_RETRY_KEY "retry="
struct pam_items {
const char* pam_service;
const char* pam_user;
const char* pam_tty;
const char* pam_ruser;
const char* pam_rhost;
char* pam_authtok;
char* pam_newauthtok;
const char* pamstack_authtok;
const char* pamstack_oldauthtok;
size_t pam_service_size;
size_t pam_user_size;
size_t pam_tty_size;
size_t pam_ruser_size;
size_t pam_rhost_size;
int pam_authtok_type;
size_t pam_authtok_size;
int pam_newauthtok_type;
size_t pam_newauthtok_size;
pid_t cli_pid;
const char *login_name;
char *domain_name;
};
#define DEBUG_MGS_LEN 1024
#define MAX_AUTHTOK_SIZE (1024*1024)
#define CHECK_AND_RETURN_PI_STRING(s) ((s != NULL && *s != '\0')? s : "(not available)")
static void logger(pam_handle_t *pamh, int level, const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
#ifdef DEBUG
va_list apd;
char debug_msg[DEBUG_MGS_LEN];
int ret;
va_copy(apd, ap);
ret = vsnprintf(debug_msg, DEBUG_MGS_LEN, fmt, apd);
if (ret >= DEBUG_MGS_LEN) {
D(("the following message is truncated: %s", debug_msg));
} else if (ret < 0) {
D(("vsnprintf failed to format debug message!"));
} else {
D((debug_msg));
}
va_end(apd);
#endif
pam_vsyslog(pamh, LOG_AUTHPRIV|level, fmt, ap);
va_end(ap);
}
static void free_exp_data(pam_handle_t *pamh, void *ptr, int err)
{
free(ptr);
ptr = NULL;
}
static size_t add_authtok_item(enum pam_item_type type,
enum sss_authtok_type authtok_type,
const char *tok, const size_t size,
uint8_t *buf) {
size_t rp=0;
uint32_t c;
if (tok == NULL) return 0;
c = type;
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
c = size + sizeof(uint32_t);
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
c = authtok_type;
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
memcpy(&buf[rp], tok, size);
rp += size;
return rp;
}
static size_t add_uint32_t_item(enum pam_item_type type, const uint32_t val,
uint8_t *buf) {
size_t rp=0;
uint32_t c;
c = type;
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
c = sizeof(uint32_t);
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
c = val;
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
return rp;
}
static size_t add_string_item(enum pam_item_type type, const char *str,
const size_t size, uint8_t *buf) {
size_t rp=0;
uint32_t c;
if (str == NULL || *str == '\0') return 0;
c = type;
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
c = size;
memcpy(&buf[rp], &c, sizeof(uint32_t));
rp += sizeof(uint32_t);
memcpy(&buf[rp], str, size);
rp += size;
return rp;
}
static void overwrite_and_free_pam_items(struct pam_items *pi)
{
if (pi->pam_authtok != NULL) {
_pam_overwrite_n((void *)pi->pam_authtok, pi->pam_authtok_size);
free((void *)pi->pam_authtok);
pi->pam_authtok = NULL;
}
if (pi->pam_newauthtok != NULL) {
_pam_overwrite_n((void *)pi->pam_newauthtok, pi->pam_newauthtok_size);
free((void *)pi->pam_newauthtok);
pi->pam_newauthtok = NULL;
}
pi->pamstack_authtok = NULL;
pi->pamstack_oldauthtok = NULL;
free(pi->domain_name);
pi->domain_name = NULL;
}
static int pack_message_v3(struct pam_items *pi, size_t *size,
uint8_t **buffer) {
int len;
uint8_t *buf;
int rp;
uint32_t terminator = SSS_END_OF_PAM_REQUEST;
len = sizeof(uint32_t) +
2*sizeof(uint32_t) + pi->pam_user_size +
sizeof(uint32_t);
len += *pi->pam_service != '\0' ?
2*sizeof(uint32_t) + pi->pam_service_size : 0;
len += *pi->pam_tty != '\0' ?
2*sizeof(uint32_t) + pi->pam_tty_size : 0;
len += *pi->pam_ruser != '\0' ?
2*sizeof(uint32_t) + pi->pam_ruser_size : 0;
len += *pi->pam_rhost != '\0' ?
2*sizeof(uint32_t) + pi->pam_rhost_size : 0;
len += pi->pam_authtok != NULL ?
3*sizeof(uint32_t) + pi->pam_authtok_size : 0;
len += pi->pam_newauthtok != NULL ?
3*sizeof(uint32_t) + pi->pam_newauthtok_size : 0;
len += 3*sizeof(uint32_t); /* cli_pid */
buf = malloc(len);
if (buf == NULL) {
D(("malloc failed."));
return PAM_BUF_ERR;
}
rp = 0;
((uint32_t *)(&buf[rp]))[0] = SSS_START_OF_PAM_REQUEST;
rp += sizeof(uint32_t);
rp += add_string_item(SSS_PAM_ITEM_USER, pi->pam_user, pi->pam_user_size,
&buf[rp]);
rp += add_string_item(SSS_PAM_ITEM_SERVICE, pi->pam_service,
pi->pam_service_size, &buf[rp]);
rp += add_string_item(SSS_PAM_ITEM_TTY, pi->pam_tty, pi->pam_tty_size,
&buf[rp]);
rp += add_string_item(SSS_PAM_ITEM_RUSER, pi->pam_ruser, pi->pam_ruser_size,
&buf[rp]);
rp += add_string_item(SSS_PAM_ITEM_RHOST, pi->pam_rhost, pi->pam_rhost_size,
&buf[rp]);
rp += add_uint32_t_item(SSS_PAM_ITEM_CLI_PID, (uint32_t) pi->cli_pid,
&buf[rp]);
rp += add_authtok_item(SSS_PAM_ITEM_AUTHTOK, pi->pam_authtok_type,
pi->pam_authtok, pi->pam_authtok_size, &buf[rp]);
rp += add_authtok_item(SSS_PAM_ITEM_NEWAUTHTOK, pi->pam_newauthtok_type,
pi->pam_newauthtok, pi->pam_newauthtok_size,
&buf[rp]);
memcpy(&buf[rp], &terminator, sizeof(uint32_t));
rp += sizeof(uint32_t);
if (rp != len) {
D(("error during packet creation."));
free(buf);
return PAM_BUF_ERR;
}
*size = len;
*buffer = buf;
return 0;
}
static int null_strcmp(const char *s1, const char *s2) {
if (s1 == NULL && s2 == NULL) return 0;
if (s1 == NULL && s2 != NULL) return -1;
if (s1 != NULL && s2 == NULL) return 1;
return strcmp(s1, s2);
}
enum {
SSS_PAM_CONV_DONE = 0,
SSS_PAM_CONV_STD,
SSS_PAM_CONV_REENTER,
};
static int do_pam_conversation(pam_handle_t *pamh, const int msg_style,
const char *msg,
const char *reenter_msg,
char **_answer)
{
int ret;
int state = SSS_PAM_CONV_STD;
struct pam_conv *conv;
const struct pam_message *mesg[1];
struct pam_message *pam_msg;
struct pam_response *resp=NULL;
char *answer = NULL;
if ((msg_style == PAM_TEXT_INFO || msg_style == PAM_ERROR_MSG) &&
msg == NULL) return PAM_SYSTEM_ERR;
if ((msg_style == PAM_PROMPT_ECHO_OFF ||
msg_style == PAM_PROMPT_ECHO_ON) &&
(msg == NULL || _answer == NULL)) return PAM_SYSTEM_ERR;
if (msg_style == PAM_TEXT_INFO || msg_style == PAM_ERROR_MSG) {
logger(pamh, LOG_INFO, "User %s message: %s",
msg_style == PAM_TEXT_INFO ? "info" : "error",
msg);
}
ret=pam_get_item(pamh, PAM_CONV, (const void **) &conv);
if (ret != PAM_SUCCESS) return ret;
do {
pam_msg = malloc(sizeof(struct pam_message));
if (pam_msg == NULL) {
D(("Malloc failed."));
ret = PAM_SYSTEM_ERR;
goto failed;
}
pam_msg->msg_style = msg_style;
if (state == SSS_PAM_CONV_REENTER) {
pam_msg->msg = reenter_msg;
} else {
pam_msg->msg = msg;
}
mesg[0] = (const struct pam_message *) pam_msg;
ret=conv->conv(1, mesg, &resp,
conv->appdata_ptr);
free(pam_msg);
if (ret != PAM_SUCCESS) {
D(("Conversation failure: %s.", pam_strerror(pamh,ret)));
goto failed;
}
if (msg_style == PAM_PROMPT_ECHO_OFF ||
msg_style == PAM_PROMPT_ECHO_ON) {
if (resp == NULL) {
D(("response expected, but resp==NULL"));
ret = PAM_SYSTEM_ERR;
goto failed;
}
if (state == SSS_PAM_CONV_REENTER) {
if (null_strcmp(answer, resp[0].resp) != 0) {
logger(pamh, LOG_NOTICE, "Passwords do not match.");
_pam_overwrite((void *)resp[0].resp);
free(resp[0].resp);
if (answer != NULL) {
_pam_overwrite((void *) answer);
free(answer);
answer = NULL;
}
ret = do_pam_conversation(pamh, PAM_ERROR_MSG,
_("Passwords do not match"),
NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
ret = PAM_SYSTEM_ERR;
goto failed;
}
ret = PAM_CRED_ERR;
goto failed;
}
_pam_overwrite((void *)resp[0].resp);
free(resp[0].resp);
} else {
if (resp[0].resp == NULL) {
D(("Empty password"));
answer = NULL;
} else {
answer = strndup(resp[0].resp, MAX_AUTHTOK_SIZE);
_pam_overwrite((void *)resp[0].resp);
free(resp[0].resp);
if(answer == NULL) {
D(("strndup failed"));
ret = PAM_BUF_ERR;
goto failed;
}
}
}
free(resp);
resp = NULL;
}
if (reenter_msg != NULL && state == SSS_PAM_CONV_STD) {
state = SSS_PAM_CONV_REENTER;
} else {
state = SSS_PAM_CONV_DONE;
}
} while (state != SSS_PAM_CONV_DONE);
if (_answer) *_answer = answer;
return PAM_SUCCESS;
failed:
free(answer);
return ret;
}
static errno_t display_pw_reset_message(pam_handle_t *pamh,
const char *domain_name,
const char *suffix)
{
int ret;
struct stat stat_buf;
char *msg_buf = NULL;
int fd = -1;
size_t size;
size_t total_len;
char *filename = NULL;
if (strchr(suffix, '/') != NULL || strchr(domain_name, '/') != NULL) {
D(("Suffix [%s] or domain name [%s] contain illegal character.", suffix,
domain_name));
return EINVAL;
}
size = sizeof(PW_RESET_MSG_FILENAME_TEMPLATE) + strlen(domain_name) +
strlen(suffix);
filename = malloc(size);
if (filename == NULL) {
D(("malloc failed."));
ret = ENOMEM;
goto done;
}
ret = snprintf(filename, size, PW_RESET_MSG_FILENAME_TEMPLATE, domain_name,
suffix);
if (ret < 0 || ret >= size) {
D(("snprintf failed."));
ret = EFAULT;
goto done;
}
fd = open(filename, O_RDONLY);
if (fd == -1) {
ret = errno;
D(("open failed [%d][%s].\n", ret, strerror(ret)));
goto done;
}
ret = fstat(fd, &stat_buf);
if (ret == -1) {
ret = errno;
D(("fstat failed [%d][%s].", ret, strerror(ret)));
goto done;
}
if (!S_ISREG(stat_buf.st_mode)) {
logger(pamh, LOG_ERR,
"Password reset message file is not a regular file.");
ret = EINVAL;
goto done;
}
if (stat_buf.st_uid != 0 || stat_buf.st_gid != 0 ||
(stat_buf.st_mode & ~S_IFMT) != 0644) {
logger(pamh, LOG_ERR,"Permission error, "
"file [%s] must be owned by root with permissions 0644.",
filename);
ret = EPERM;
goto done;
}
if (stat_buf.st_size > PW_RESET_MSG_MAX_SIZE) {
logger(pamh, LOG_ERR, "Password reset message file is too large.");
ret = EFBIG;
goto done;
}
msg_buf = malloc(stat_buf.st_size + 1);
if (msg_buf == NULL) {
D(("malloc failed."));
ret = ENOMEM;
goto done;
}
total_len = 0;
while (total_len < stat_buf.st_size) {
ret = read(fd, msg_buf + total_len, stat_buf.st_size - total_len);
if (ret == -1) {
if (errno == EINTR || errno == EAGAIN) continue;
ret = errno;
D(("read failed [%d][%s].", ret, strerror(ret)));
goto done;
}
total_len += ret;
}
ret = close(fd);
fd = -1;
if (ret == -1) {
ret = errno;
D(("close failed [%d][%s].", ret, strerror(ret)));
}
if (total_len != stat_buf.st_size) {
D(("read fewer bytes [%d] than expected [%d].", total_len,
stat_buf.st_size));
ret = EIO;
goto done;
}
msg_buf[stat_buf.st_size] = '\0';
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, msg_buf, NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
}
done:
if (fd != -1) {
close(fd);
}
free(msg_buf);
free(filename);
return ret;
}
static errno_t select_pw_reset_message(pam_handle_t *pamh, struct pam_items *pi)
{
int ret;
char *locale;
const char *domain_name;
domain_name = pi->domain_name;
if (domain_name == NULL || *domain_name == '\0') {
D(("Domain name is unknown."));
return EINVAL;
}
locale = setlocale(LC_MESSAGES, NULL);
ret = -1;
if (locale != NULL) {
ret = display_pw_reset_message(pamh, domain_name, locale);
}
if (ret != 0) {
ret = display_pw_reset_message(pamh, domain_name, "txt");
}
if (ret != 0) {
ret = do_pam_conversation(pamh, PAM_TEXT_INFO,
_("Password reset by root is not supported."),
NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
}
}
return ret;
}
static int user_info_offline_auth(pam_handle_t *pamh, size_t buflen,
uint8_t *buf)
{
int ret;
int64_t expire_date;
struct tm tm;
char expire_str[128];
char user_msg[256];
expire_str[0] = '\0';
if (buflen != sizeof(uint32_t) + sizeof(int64_t)) {
D(("User info response data has the wrong size"));
return PAM_BUF_ERR;
}
memcpy(&expire_date, buf + sizeof(uint32_t), sizeof(int64_t));
if (expire_date > 0) {
if (localtime_r((time_t *) &expire_date, &tm) != NULL) {
ret = strftime(expire_str, sizeof(expire_str), "%c", &tm);
if (ret == 0) {
D(("strftime failed."));
expire_str[0] = '\0';
}
} else {
D(("localtime_r failed"));
}
}
ret = snprintf(user_msg, sizeof(user_msg), "%s%s%s.",
_("Authenticated with cached credentials"),
expire_str[0] ? _(", your cached password will expire at: ") : "",
expire_str[0] ? expire_str : "");
if (ret < 0 || ret >= sizeof(user_msg)) {
D(("snprintf failed."));
return PAM_SYSTEM_ERR;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, user_msg, NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return PAM_SYSTEM_ERR;
}
return PAM_SUCCESS;
}
static int user_info_grace_login(pam_handle_t *pamh,
size_t buflen,
uint8_t *buf)
{
int ret;
uint32_t grace;
char user_msg[256];
if (buflen != 2* sizeof(uint32_t)) {
D(("User info response data has the wrong size"));
return PAM_BUF_ERR;
}
memcpy(&grace, buf + sizeof(uint32_t), sizeof(uint32_t));
ret = snprintf(user_msg, sizeof(user_msg),
_("Your password has expired. "
"You have %d grace login(s) remaining."),
grace);
if (ret < 0 || ret >= sizeof(user_msg)) {
D(("snprintf failed."));
return PAM_SYSTEM_ERR;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, user_msg, NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return PAM_SYSTEM_ERR;
}
return PAM_SUCCESS;
}
#define MINSEC 60
#define HOURSEC (60*MINSEC)
#define DAYSEC (24*HOURSEC)
static int user_info_expire_warn(pam_handle_t *pamh,
size_t buflen,
uint8_t *buf)
{
int ret;
uint32_t expire;
char user_msg[256];
const char* unit="second(s)";
if (buflen != 2* sizeof(uint32_t)) {
D(("User info response data has the wrong size"));
return PAM_BUF_ERR;
}
memcpy(&expire, buf + sizeof(uint32_t), sizeof(uint32_t));
if (expire >= DAYSEC) {
expire /= DAYSEC;
unit = "day(s)";
} else if (expire >= HOURSEC) {
expire /= HOURSEC;
unit = "hour(s)";
} else if (expire >= MINSEC) {
expire /= MINSEC;
unit = "minute(s)";
}
ret = snprintf(user_msg, sizeof(user_msg),
_("Your password will expire in %d %s."), expire, unit);
if (ret < 0 || ret >= sizeof(user_msg)) {
D(("snprintf failed."));
return PAM_SYSTEM_ERR;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, user_msg, NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return PAM_SYSTEM_ERR;
}
return PAM_SUCCESS;
}
static int user_info_offline_auth_delayed(pam_handle_t *pamh, size_t buflen,
uint8_t *buf)
{
int ret;
int64_t delayed_until;
struct tm tm;
char delay_str[128];
char user_msg[256];
delay_str[0] = '\0';
if (buflen != sizeof(uint32_t) + sizeof(int64_t)) {
D(("User info response data has the wrong size"));
return PAM_BUF_ERR;
}
memcpy(&delayed_until, buf + sizeof(uint32_t), sizeof(int64_t));
if (delayed_until <= 0) {
D(("User info response data has an invalid value"));
return PAM_BUF_ERR;
}
if (localtime_r((time_t *) &delayed_until, &tm) != NULL) {
ret = strftime(delay_str, sizeof(delay_str), "%c", &tm);
if (ret == 0) {
D(("strftime failed."));
delay_str[0] = '\0';
}
} else {
D(("localtime_r failed"));
}
ret = snprintf(user_msg, sizeof(user_msg), "%s%s.",
_("Authentication is denied until: "),
delay_str);
if (ret < 0 || ret >= sizeof(user_msg)) {
D(("snprintf failed."));
return PAM_SYSTEM_ERR;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, user_msg, NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return PAM_SYSTEM_ERR;
}
return PAM_SUCCESS;
}
static int user_info_offline_chpass(pam_handle_t *pamh, size_t buflen,
uint8_t *buf)
{
int ret;
if (buflen != sizeof(uint32_t)) {
D(("User info response data has the wrong size"));
return PAM_BUF_ERR;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO,
_("System is offline, password change not possible"),
NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return PAM_SYSTEM_ERR;
}
return PAM_SUCCESS;
}
static int user_info_chpass_error(pam_handle_t *pamh, size_t buflen,
uint8_t *buf)
{
int ret;
uint32_t msg_len;
char *user_msg;
size_t bufsize = 0;
if (buflen < 2* sizeof(uint32_t)) {
D(("User info response data is too short"));
return PAM_BUF_ERR;
}
memcpy(&msg_len, buf + sizeof(uint32_t), sizeof(uint32_t));
if (buflen != 2* sizeof(uint32_t) + msg_len) {
D(("User info response data has the wrong size"));
return PAM_BUF_ERR;
}
bufsize = strlen(_("Password change failed. ")) + 1;
if (msg_len > 0) {
bufsize += strlen(_("Server message: ")) + msg_len;
}
user_msg = (char *)malloc(sizeof(char) * bufsize);
if (!user_msg) {
D(("Out of memory."));
return PAM_SYSTEM_ERR;
}
ret = snprintf(user_msg, bufsize, "%s%s%.*s",
_("Password change failed. "),
msg_len > 0 ? _("Server message: ") : "",
msg_len,
msg_len > 0 ? (char *)(buf + 2 * sizeof(uint32_t)) : "" );
if (ret < 0 || ret > bufsize) {
D(("snprintf failed."));
free(user_msg);
return PAM_SYSTEM_ERR;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, user_msg, NULL, NULL);
free(user_msg);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return PAM_SYSTEM_ERR;
}
return PAM_SUCCESS;
}
static int eval_user_info_response(pam_handle_t *pamh, size_t buflen,
uint8_t *buf)
{
int ret;
uint32_t type;
if (buflen < sizeof(uint32_t)) {
D(("User info response data is too short"));
return PAM_BUF_ERR;
}
memcpy(&type, buf, sizeof(uint32_t));
switch(type) {
case SSS_PAM_USER_INFO_OFFLINE_AUTH:
ret = user_info_offline_auth(pamh, buflen, buf);
break;
case SSS_PAM_USER_INFO_GRACE_LOGIN:
ret = user_info_grace_login(pamh, buflen, buf);
break;
case SSS_PAM_USER_INFO_EXPIRE_WARN:
ret = user_info_expire_warn(pamh, buflen, buf);
break;
case SSS_PAM_USER_INFO_OFFLINE_AUTH_DELAYED:
ret = user_info_offline_auth_delayed(pamh, buflen, buf);
break;
case SSS_PAM_USER_INFO_OFFLINE_CHPASS:
ret = user_info_offline_chpass(pamh, buflen, buf);
break;
case SSS_PAM_USER_INFO_CHPASS_ERROR:
ret = user_info_chpass_error(pamh, buflen, buf);
break;
default:
D(("Unknown user info type [%d]", type));
ret = PAM_SYSTEM_ERR;
}
return ret;
}
static int eval_response(pam_handle_t *pamh, size_t buflen, uint8_t *buf,
struct pam_items *pi)
{
int ret;
size_t p=0;
char *env_item;
int32_t c;
int32_t type;
int32_t len;
int32_t pam_status;
if (buflen < (2*sizeof(int32_t))) {
D(("response buffer is too small"));
return PAM_BUF_ERR;
}
memcpy(&pam_status, buf+p, sizeof(int32_t));
p += sizeof(int32_t);
memcpy(&c, buf+p, sizeof(int32_t));
p += sizeof(int32_t);
while(c>0) {
if (buflen < (p+2*sizeof(int32_t))) {
D(("response buffer is too small"));
return PAM_BUF_ERR;
}
memcpy(&type, buf+p, sizeof(int32_t));
p += sizeof(int32_t);
memcpy(&len, buf+p, sizeof(int32_t));
p += sizeof(int32_t);
if (buflen < (p + len)) {
D(("response buffer is too small"));
return PAM_BUF_ERR;
}
switch(type) {
case SSS_PAM_SYSTEM_INFO:
if (buf[p + (len -1)] != '\0') {
D(("system info does not end with \\0."));
break;
}
logger(pamh, LOG_INFO, "system info: [%s]", &buf[p]);
break;
case SSS_PAM_DOMAIN_NAME:
if (buf[p + (len -1)] != '\0') {
D(("domain name does not end with \\0."));
break;
}
D(("domain name: [%s]", &buf[p]));
pi->domain_name = strdup((char *) &buf[p]);
if (pi->domain_name == NULL) {
D(("strdup failed"));
}
break;
case SSS_ENV_ITEM:
case SSS_PAM_ENV_ITEM:
case SSS_ALL_ENV_ITEM:
if (buf[p + (len -1)] != '\0') {
D(("env item does not end with \\0."));
break;
}
D(("env item: [%s]", &buf[p]));
if (type == SSS_PAM_ENV_ITEM || type == SSS_ALL_ENV_ITEM) {
ret = pam_putenv(pamh, (char *)&buf[p]);
if (ret != PAM_SUCCESS) {
D(("pam_putenv failed."));
break;
}
}
if (type == SSS_ENV_ITEM || type == SSS_ALL_ENV_ITEM) {
env_item = strdup((char *)&buf[p]);
if (env_item == NULL) {
D(("strdup failed"));
break;
}
ret = putenv(env_item);
if (ret == -1) {
D(("putenv failed."));
break;
}
}
break;
case SSS_PAM_USER_INFO:
ret = eval_user_info_response(pamh, len, &buf[p]);
if (ret != PAM_SUCCESS) {
D(("eval_user_info_response failed"));
}
break;
case SSS_PAM_TEXT_MSG:
if (buf[p + (len -1)] != '\0') {
D(("system info does not end with \\0."));
break;
}
ret = do_pam_conversation(pamh, PAM_TEXT_INFO, (char *) &buf[p],
NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
}
break;
default:
D(("Unknown response type [%d]", type));
}
p += len;
--c;
}
return PAM_SUCCESS;
}
static int get_pam_items(pam_handle_t *pamh, struct pam_items *pi)
{
int ret;
pi->pam_authtok_type = SSS_AUTHTOK_TYPE_EMPTY;
pi->pam_authtok = NULL;
pi->pam_authtok_size = 0;
pi->pam_newauthtok_type = SSS_AUTHTOK_TYPE_EMPTY;
pi->pam_newauthtok = NULL;
pi->pam_newauthtok_size = 0;
ret = pam_get_item(pamh, PAM_SERVICE, (const void **) &(pi->pam_service));
if (ret != PAM_SUCCESS) return ret;
if (pi->pam_service == NULL) pi->pam_service="";
pi->pam_service_size=strlen(pi->pam_service)+1;
ret = pam_get_item(pamh, PAM_USER, (const void **) &(pi->pam_user));
if (ret != PAM_SUCCESS) return ret;
if (pi->pam_user == NULL) {
D(("No user found, aborting."));
return PAM_BAD_ITEM;
}
if (strcmp(pi->pam_user, "root") == 0) {
D(("pam_sss will not handle root."));
return PAM_USER_UNKNOWN;
}
pi->pam_user_size=strlen(pi->pam_user)+1;
ret = pam_get_item(pamh, PAM_TTY, (const void **) &(pi->pam_tty));
if (ret != PAM_SUCCESS) return ret;
if (pi->pam_tty == NULL) pi->pam_tty="";
pi->pam_tty_size=strlen(pi->pam_tty)+1;
ret = pam_get_item(pamh, PAM_RUSER, (const void **) &(pi->pam_ruser));
if (ret != PAM_SUCCESS) return ret;
if (pi->pam_ruser == NULL) pi->pam_ruser="";
pi->pam_ruser_size=strlen(pi->pam_ruser)+1;
ret = pam_get_item(pamh, PAM_RHOST, (const void **) &(pi->pam_rhost));
if (ret != PAM_SUCCESS) return ret;
if (pi->pam_rhost == NULL) pi->pam_rhost="";
pi->pam_rhost_size=strlen(pi->pam_rhost)+1;
ret = pam_get_item(pamh, PAM_AUTHTOK,
(const void **) &(pi->pamstack_authtok));
if (ret != PAM_SUCCESS) return ret;
if (pi->pamstack_authtok == NULL) pi->pamstack_authtok="";
ret = pam_get_item(pamh, PAM_OLDAUTHTOK,
(const void **) &(pi->pamstack_oldauthtok));
if (ret != PAM_SUCCESS) return ret;
if (pi->pamstack_oldauthtok == NULL) pi->pamstack_oldauthtok="";
pi->cli_pid = getpid();
pi->login_name = pam_modutil_getlogin(pamh);
if (pi->login_name == NULL) pi->login_name="";
pi->domain_name = NULL;
return PAM_SUCCESS;
}
static void print_pam_items(struct pam_items *pi)
{
if (pi == NULL) return;
D(("Service: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_service)));
D(("User: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_user)));
D(("Tty: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_tty)));
D(("Ruser: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_ruser)));
D(("Rhost: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_rhost)));
D(("Pamstack_Authtok: %s",
CHECK_AND_RETURN_PI_STRING(pi->pamstack_authtok)));
D(("Pamstack_Oldauthtok: %s",
CHECK_AND_RETURN_PI_STRING(pi->pamstack_oldauthtok)));
D(("Authtok: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_authtok)));
D(("Newauthtok: %s", CHECK_AND_RETURN_PI_STRING(pi->pam_newauthtok)));
D(("Cli_PID: %d", pi->cli_pid));
}
static int send_and_receive(pam_handle_t *pamh, struct pam_items *pi,
enum sss_cli_command task, bool quiet_mode)
{
int ret;
int errnop;
struct sss_cli_req_data rd;
uint8_t *buf = NULL;
uint8_t *repbuf = NULL;
size_t replen;
int pam_status = PAM_SYSTEM_ERR;
print_pam_items(pi);
ret = pack_message_v3(pi, &rd.len, &buf);
if (ret != 0) {
D(("pack_message failed."));
pam_status = PAM_SYSTEM_ERR;
goto done;
}
rd.data = buf;
errnop = 0;
ret = sss_pam_make_request(task, &rd, &repbuf, &replen, &errnop);
if (ret != PAM_SUCCESS) {
if (errnop != 0) {
logger(pamh, LOG_ERR, "Request to sssd failed. %s", ssscli_err2string(errnop));
}
pam_status = PAM_SYSTEM_ERR;
goto done;
}
/* FIXME: add an end signature */
if (replen < (2*sizeof(int32_t))) {
D(("response not in expected format."));
pam_status = PAM_SYSTEM_ERR;
goto done;
}
pam_status = ((int32_t *)repbuf)[0];
ret = eval_response(pamh, replen, repbuf, pi);
if (ret != PAM_SUCCESS) {
D(("eval_response failed."));
pam_status = ret;
goto done;
}
switch (task) {
case SSS_PAM_AUTHENTICATE:
logger(pamh, (pam_status == PAM_SUCCESS ? LOG_INFO : LOG_NOTICE),
"authentication %s; logname=%s uid=%lu euid=%d tty=%s "
"ruser=%s rhost=%s user=%s",
pam_status == PAM_SUCCESS ? "success" : "failure",
pi->login_name, getuid(), (unsigned long) geteuid(),
pi->pam_tty, pi->pam_ruser, pi->pam_rhost, pi->pam_user);
if (pam_status != PAM_SUCCESS) {
/* don't log if quiet_mode is on and pam_status is
* User not known to the underlying authentication module
*/
if (!quiet_mode || pam_status != 10) {
logger(pamh, LOG_NOTICE, "received for user %s: %d (%s)",
pi->pam_user, pam_status,
pam_strerror(pamh,pam_status));
}
}
break;
case SSS_PAM_CHAUTHTOK_PRELIM:
if (pam_status != PAM_SUCCESS) {
/* don't log if quiet_mode is on and pam_status is
* User not known to the underlying authentication module
*/
if (!quiet_mode || pam_status != 10) {
logger(pamh, LOG_NOTICE,
"Authentication failed for user %s: %d (%s)",
pi->pam_user, pam_status,
pam_strerror(pamh,pam_status));
}
}
break;
case SSS_PAM_CHAUTHTOK:
if (pam_status != PAM_SUCCESS) {
logger(pamh, LOG_NOTICE,
"Password change failed for user %s: %d (%s)",
pi->pam_user, pam_status,
pam_strerror(pamh,pam_status));
}
break;
case SSS_PAM_ACCT_MGMT:
if (pam_status != PAM_SUCCESS) {
/* don't log if quiet_mode is on and pam_status is
* User not known to the underlying authentication module
*/
if (!quiet_mode || pam_status != 10) {
logger(pamh, LOG_NOTICE,
"Access denied for user %s: %d (%s)",
pi->pam_user, pam_status,
pam_strerror(pamh,pam_status));
}
}
break;
case SSS_PAM_SETCRED:
case SSS_PAM_OPEN_SESSION:
case SSS_PAM_CLOSE_SESSION:
break;
default:
D(("Illegal task [%d]", task));
return PAM_SYSTEM_ERR;
}
done:
if (buf != NULL ) {
_pam_overwrite_n((void *)buf, rd.len);
free(buf);
}
free(repbuf);
return pam_status;
}
static int prompt_password(pam_handle_t *pamh, struct pam_items *pi,
const char *prompt)
{
int ret;
char *answer = NULL;
ret = do_pam_conversation(pamh, PAM_PROMPT_ECHO_OFF, prompt, NULL, &answer);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return ret;
}
if (answer == NULL) {
pi->pam_authtok = NULL;
pi->pam_authtok_type = SSS_AUTHTOK_TYPE_EMPTY;
pi->pam_authtok_size=0;
} else {
pi->pam_authtok = strdup(answer);
_pam_overwrite((void *)answer);
free(answer);
answer=NULL;
if (pi->pam_authtok == NULL) {
return PAM_BUF_ERR;
}
pi->pam_authtok_type = SSS_AUTHTOK_TYPE_PASSWORD;
pi->pam_authtok_size=strlen(pi->pam_authtok);
}
return PAM_SUCCESS;
}
static int prompt_new_password(pam_handle_t *pamh, struct pam_items *pi)
{
int ret;
char *answer = NULL;
ret = do_pam_conversation(pamh, PAM_PROMPT_ECHO_OFF,
_("New Password: "),
_("Reenter new Password: "),
&answer);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
return ret;
}
if (answer == NULL) {
pi->pam_newauthtok = NULL;
pi->pam_newauthtok_type = SSS_AUTHTOK_TYPE_EMPTY;
pi->pam_newauthtok_size=0;
} else {
pi->pam_newauthtok = strdup(answer);
_pam_overwrite((void *)answer);
free(answer);
answer=NULL;
if (pi->pam_newauthtok == NULL) {
return PAM_BUF_ERR;
}
pi->pam_newauthtok_type = SSS_AUTHTOK_TYPE_PASSWORD;
pi->pam_newauthtok_size=strlen(pi->pam_newauthtok);
}
return PAM_SUCCESS;
}
static void eval_argv(pam_handle_t *pamh, int argc, const char **argv,
uint32_t *flags, int *retries, bool *quiet_mode)
{
char *ep;
*quiet_mode = false;
for (; argc-- > 0; ++argv) {
if (strcmp(*argv, "forward_pass") == 0) {
*flags |= FLAGS_FORWARD_PASS;
} else if (strcmp(*argv, "use_first_pass") == 0) {
*flags |= FLAGS_USE_FIRST_PASS;
} else if (strcmp(*argv, "use_authtok") == 0) {
*flags |= FLAGS_USE_AUTHTOK;
} else if (strncmp(*argv, OPT_RETRY_KEY, strlen(OPT_RETRY_KEY)) == 0) {
if (*(*argv+6) == '\0') {
logger(pamh, LOG_ERR, "Missing argument to option retry.");
*retries = 0;
} else {
errno = 0;
*retries = strtol(*argv+6, &ep, 10);
if (errno != 0) {
D(("strtol failed [%d][%s]", errno, strerror(errno)));
*retries = 0;
}
if (*ep != '\0') {
logger(pamh, LOG_ERR, "Argument to option retry contains "
"extra characters.");
*retries = 0;
}
if (*retries < 0) {
logger(pamh, LOG_ERR, "Argument to option retry must not "
"be negative.");
*retries = 0;
}
}
} else if (strcmp(*argv, "quiet") == 0) {
*quiet_mode = true;
} else {
logger(pamh, LOG_WARNING, "unknown option: %s", *argv);
}
}
return;
}
static int get_authtok_for_authentication(pam_handle_t *pamh,
struct pam_items *pi,
uint32_t flags)
{
int ret;
if (flags & FLAGS_USE_FIRST_PASS) {
pi->pam_authtok_type = SSS_AUTHTOK_TYPE_PASSWORD;
pi->pam_authtok = strdup(pi->pamstack_authtok);
if (pi->pam_authtok == NULL) {
D(("option use_first_pass set, but no password found"));
return PAM_BUF_ERR;
}
pi->pam_authtok_size = strlen(pi->pam_authtok);
} else {
ret = prompt_password(pamh, pi, _("Password: "));
if (ret != PAM_SUCCESS) {
D(("failed to get password from user"));
return ret;
}
if (flags & FLAGS_FORWARD_PASS) {
ret = pam_set_item(pamh, PAM_AUTHTOK, pi->pam_authtok);
if (ret != PAM_SUCCESS) {
D(("Failed to set PAM_AUTHTOK [%s], "
"authtok may not be available for other modules",
pam_strerror(pamh,ret)));
}
}
}
return PAM_SUCCESS;
}
static int get_authtok_for_password_change(pam_handle_t *pamh,
struct pam_items *pi,
uint32_t flags,
int pam_flags)
{
int ret;
int *exp_data = NULL;
pam_get_data(pamh, PWEXP_FLAG, (const void **) &exp_data);
/* we query for the old password during PAM_PRELIM_CHECK to make
* pam_sss work e.g. with pam_cracklib */
if (pam_flags & PAM_PRELIM_CHECK) {
if ( (getuid() != 0 || exp_data ) && !(flags & FLAGS_USE_FIRST_PASS)) {
ret = prompt_password(pamh, pi, _("Current Password: "));
if (ret != PAM_SUCCESS) {
D(("failed to get password from user"));
return ret;
}
ret = pam_set_item(pamh, PAM_OLDAUTHTOK, pi->pam_authtok);
if (ret != PAM_SUCCESS) {
D(("Failed to set PAM_OLDAUTHTOK [%s], "
"oldauthtok may not be available",
pam_strerror(pamh,ret)));
return ret;
}
}
return PAM_SUCCESS;
}
if (pi->pamstack_oldauthtok == NULL) {
if (getuid() != 0) {
D(("no password found for chauthtok"));
return PAM_BUF_ERR;
} else {
pi->pam_authtok_type = SSS_AUTHTOK_TYPE_EMPTY;
pi->pam_authtok = NULL;
pi->pam_authtok_size = 0;
}
} else {
pi->pam_authtok = strdup(pi->pamstack_oldauthtok);
pi->pam_authtok_type = SSS_AUTHTOK_TYPE_PASSWORD;
pi->pam_authtok_size = strlen(pi->pam_authtok);
}
if (flags & FLAGS_USE_AUTHTOK) {
pi->pam_newauthtok_type = SSS_AUTHTOK_TYPE_PASSWORD;
pi->pam_newauthtok = strdup(pi->pamstack_authtok);
if (pi->pam_newauthtok == NULL) {
D(("option use_authtok set, but no new password found"));
return PAM_BUF_ERR;
}
pi->pam_newauthtok_size = strlen(pi->pam_newauthtok);
} else {
ret = prompt_new_password(pamh, pi);
if (ret != PAM_SUCCESS) {
D(("failed to get new password from user"));
return ret;
}
if (flags & FLAGS_FORWARD_PASS) {
ret = pam_set_item(pamh, PAM_AUTHTOK, pi->pam_newauthtok);
if (ret != PAM_SUCCESS) {
D(("Failed to set PAM_AUTHTOK [%s], "
"oldauthtok may not be available",
pam_strerror(pamh,ret)));
}
}
}
return PAM_SUCCESS;
}
static int pam_sss(enum sss_cli_command task, pam_handle_t *pamh,
int pam_flags, int argc, const char **argv)
{
int ret;
int pam_status;
struct pam_items pi;
uint32_t flags = 0;
int *exp_data;
bool retry = false;
bool quiet_mode = false;
int retries = 0;
bindtextdomain(PACKAGE, LOCALEDIR);
D(("Hello pam_sssd: %d", task));
eval_argv(pamh, argc, argv, &flags, &retries, &quiet_mode);
ret = get_pam_items(pamh, &pi);
if (ret != PAM_SUCCESS) {
D(("get items returned error: %s", pam_strerror(pamh,ret)));
return ret;
}
do {
retry = false;
switch(task) {
case SSS_PAM_AUTHENTICATE:
ret = get_authtok_for_authentication(pamh, &pi, flags);
if (ret != PAM_SUCCESS) {
D(("failed to get authentication token: %s",
pam_strerror(pamh, ret)));
return ret;
}
break;
case SSS_PAM_CHAUTHTOK:
ret = get_authtok_for_password_change(pamh, &pi, flags, pam_flags);
if (ret != PAM_SUCCESS) {
D(("failed to get tokens for password change: %s",
pam_strerror(pamh, ret)));
return ret;
}
if (pam_flags & PAM_PRELIM_CHECK) {
task = SSS_PAM_CHAUTHTOK_PRELIM;
}
break;
case SSS_PAM_ACCT_MGMT:
case SSS_PAM_SETCRED:
case SSS_PAM_OPEN_SESSION:
case SSS_PAM_CLOSE_SESSION:
break;
default:
D(("Illegal task [%d]", task));
return PAM_SYSTEM_ERR;
}
pam_status = send_and_receive(pamh, &pi, task, quiet_mode);
switch (task) {
case SSS_PAM_AUTHENTICATE:
/* We allow sssd to send the return code PAM_NEW_AUTHTOK_REQD during
* authentication, see sss_cli.h for details */
if (pam_status == PAM_NEW_AUTHTOK_REQD) {
D(("Authtoken expired, trying to change it"));
exp_data = malloc(sizeof(int));
if (exp_data == NULL) {
D(("malloc failed."));
pam_status = PAM_BUF_ERR;
break;
}
*exp_data = 1;
pam_status = pam_set_data(pamh, PWEXP_FLAG, exp_data,
free_exp_data);
if (pam_status != PAM_SUCCESS) {
D(("pam_set_data failed."));
}
}
break;
case SSS_PAM_ACCT_MGMT:
if (pam_status == PAM_SUCCESS &&
pam_get_data(pamh, PWEXP_FLAG, (const void **) &exp_data) ==
PAM_SUCCESS) {
ret = do_pam_conversation(pamh, PAM_TEXT_INFO,
_("Password expired. Change your password now."),
NULL, NULL);
if (ret != PAM_SUCCESS) {
D(("do_pam_conversation failed."));
}
pam_status = PAM_NEW_AUTHTOK_REQD;
}
break;
case SSS_PAM_CHAUTHTOK:
if (pam_status != PAM_SUCCESS && pam_status != PAM_USER_UNKNOWN) {
ret = pam_set_item(pamh, PAM_AUTHTOK, NULL);
if (ret != PAM_SUCCESS) {
D(("Failed to unset PAM_AUTHTOK [%s]",
pam_strerror(pamh,ret)));
}
ret = pam_set_item(pamh, PAM_OLDAUTHTOK, NULL);
if (ret != PAM_SUCCESS) {
D(("Failed to unset PAM_OLDAUTHTOK [%s]",
pam_strerror(pamh,ret)));
}
}
break;
case SSS_PAM_CHAUTHTOK_PRELIM:
if (pam_status == PAM_PERM_DENIED && pi.pam_authtok_size == 0 &&
getuid() == 0 &&
pam_get_data(pamh, PWEXP_FLAG, (const void **) &exp_data) !=
PAM_SUCCESS) {
ret = select_pw_reset_message(pamh, &pi);
if (ret != 0) {
D(("select_pw_reset_message failed.\n"));
}
}
default:
/* nothing to do */
break;
}
overwrite_and_free_pam_items(&pi);
D(("retries [%d].", retries));
if (pam_status != PAM_SUCCESS &&
(task == SSS_PAM_AUTHENTICATE || task == SSS_PAM_CHAUTHTOK_PRELIM) &&
retries > 0) {
retry = true;
retries--;
flags &= ~FLAGS_USE_FIRST_PASS;
ret = pam_set_item(pamh, PAM_AUTHTOK, NULL);
if (ret != PAM_SUCCESS) {
D(("Failed to unset PAM_AUTHTOK [%s]",
pam_strerror(pamh,ret)));
}
ret = pam_set_item(pamh, PAM_OLDAUTHTOK, NULL);
if (ret != PAM_SUCCESS) {
D(("Failed to unset PAM_OLDAUTHTOK [%s]",
pam_strerror(pamh,ret)));
}
}
} while(retry);
return pam_status;
}
PAM_EXTERN int pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc,
const char **argv )
{
return pam_sss(SSS_PAM_AUTHENTICATE, pamh, flags, argc, argv);
}
PAM_EXTERN int pam_sm_setcred(pam_handle_t *pamh, int flags, int argc,
const char **argv )
{
return pam_sss(SSS_PAM_SETCRED, pamh, flags, argc, argv);
}
PAM_EXTERN int pam_sm_acct_mgmt(pam_handle_t *pamh, int flags, int argc,
const char **argv )
{
return pam_sss(SSS_PAM_ACCT_MGMT, pamh, flags, argc, argv);
}
PAM_EXTERN int pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc,
const char **argv )
{
return pam_sss(SSS_PAM_CHAUTHTOK, pamh, flags, argc, argv);
}
PAM_EXTERN int pam_sm_open_session(pam_handle_t *pamh, int flags, int argc,
const char **argv )
{
return pam_sss(SSS_PAM_OPEN_SESSION, pamh, flags, argc, argv);
}
PAM_EXTERN int pam_sm_close_session(pam_handle_t *pamh, int flags, int argc,
const char **argv )
{
return pam_sss(SSS_PAM_CLOSE_SESSION, pamh, flags, argc, argv);
}
#ifdef PAM_STATIC
/* static module data */
struct pam_module _pam_sssd_modstruct ={
"pam_sssd",
pam_sm_authenticate,
pam_sm_setcred,
pam_sm_acct_mgmt,
pam_sm_open_session,
pam_sm_close_session,
pam_sm_chauthtok
};
#endif