diff options
Diffstat (limited to 'server/sss_client/pam_sss.c')
| -rw-r--r-- | server/sss_client/pam_sss.c | 1166 |
1 files changed, 1166 insertions, 0 deletions
diff --git a/server/sss_client/pam_sss.c b/server/sss_client/pam_sss.c new file mode 100644 index 00000000..8a1e3129 --- /dev/null +++ b/server/sss_client/pam_sss.c @@ -0,0 +1,1166 @@ +/* + Authors: + Sumit Bose <sbose@redhat.com> + + Copyright (C) 2009 Red Hat + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU 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 General Public License for more details. + + You should have received a copy of the GNU 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 <sys/types.h> +#include <unistd.h> +#include <stdlib.h> +#include <stdint.h> +#include <stdio.h> +#include <syslog.h> +#include <time.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) +#include "config.h" + +#define FLAGS_USE_FIRST_PASS (1 << 0) +#define FLAGS_FORWARD_PASS (1 << 1) +#define FLAGS_USE_AUTHTOK (1 << 2) + +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; +}; + +#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 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_authtoks(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; + } +} + +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.")); + 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; + struct pam_message *mesg[1]; + struct pam_response *resp=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 { + mesg[0] = malloc(sizeof(struct pam_message)); + if (mesg[0] == NULL) { + D(("Malloc failed.")); + return PAM_SYSTEM_ERR; + } + + mesg[0]->msg_style = msg_style; + if (state == SSS_PAM_CONV_REENTER) { + mesg[0]->msg = reenter_msg; + } else { + mesg[0]->msg = msg; + } + + ret=conv->conv(1, (const struct pam_message **) mesg, &resp, + conv->appdata_ptr); + free(mesg[0]); + if (ret != PAM_SUCCESS) { + D(("Conversation failure: %s.", pam_strerror(pamh,ret))); + return ret; + } + + if (msg_style == PAM_PROMPT_ECHO_OFF || + msg_style == PAM_PROMPT_ECHO_ON) { + if (resp == NULL) { + D(("response expected, but resp==NULL")); + return PAM_SYSTEM_ERR; + } + + 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.")); + return PAM_SYSTEM_ERR; + } + return PAM_CRED_ERR; + } + _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")); + return PAM_BUF_ERR; + } + } + } + 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); + + return PAM_SUCCESS; +} + +static int user_info_offline_auth(pam_handle_t *pamh, size_t buflen, + uint8_t *buf) +{ + int ret; + long long expire_date; + struct tm tm; + char expire_str[128]; + char user_msg[256]; + + expire_str[0] = '\0'; + + if (buflen != sizeof(uint32_t) + sizeof(long long)) { + D(("User info response data has the wrong size")); + return PAM_BUF_ERR; + } + + memcpy(&expire_date, buf + sizeof(uint32_t), sizeof(long long)); + + 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.", + _("Offline authentication"), + 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_offline_auth_delayed(pam_handle_t *pamh, size_t buflen, + uint8_t *buf) +{ + int ret; + long long delayed_until; + struct tm tm; + char delay_str[128]; + char user_msg[256]; + + delay_str[0] = '\0'; + + if (buflen != sizeof(uint32_t) + sizeof(long long)) { + D(("User info response data has the wrong size")); + return PAM_BUF_ERR; + } + + memcpy(&delayed_until, buf + sizeof(uint32_t), sizeof(long long)); + + 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.", + _("Offline authentication, 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[256]; + + 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; + } + + ret = snprintf(user_msg, sizeof(user_msg), "%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 >= 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 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_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) +{ + 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(("user info does not end with \\0.")); + break; + } + logger(pamh, LOG_INFO, "system info: [%s]", &buf[p]); + break; + case SSS_PAM_DOMAIN_NAME: + D(("domain name: [%s]", &buf[p])); + 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; + 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=""; + + 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) +{ + 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; + + ret = sss_pam_make_request(task, &rd, &repbuf, &replen, &errnop); + + if (ret != NSS_STATUS_SUCCESS) { + logger(pamh, LOG_ERR, "Request to sssd failed."); + 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); + 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) { + 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) { + 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) { + 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) +{ + int ret; + char *answer = NULL; + + ret = do_pam_conversation(pamh, PAM_PROMPT_ECHO_OFF, _("Password: "), + 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) +{ + 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 { + 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); + 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; + + /* 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 && !(flags & FLAGS_USE_FIRST_PASS)) { + ret = prompt_password(pamh, pi); + 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; + struct pam_items pi; + uint32_t flags = 0; + + bindtextdomain(PACKAGE, LOCALEDIR); + + D(("Hello pam_sssd: %d", task)); + + eval_argv(pamh, argc, argv, &flags); + + ret = get_pam_items(pamh, &pi); + if (ret != PAM_SUCCESS) { + D(("get items returned error: %s", pam_strerror(pamh,ret))); + return ret; + } + + + 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; + } + + ret = send_and_receive(pamh, &pi, task); + + if (ret == PAM_AUTHTOK_EXPIRED && task == SSS_PAM_AUTHENTICATE) { + D(("Authtoken expired, trying to change it")); + ret = do_pam_conversation(pamh, PAM_ERROR_MSG, + _("Password has expired."), NULL, NULL); + if (ret != PAM_SUCCESS) { + D(("do_pam_conversation failed.")); + return PAM_SYSTEM_ERR; + } + + pi.pamstack_oldauthtok = pi.pam_authtok; + 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; + } + + ret = send_and_receive(pamh, &pi, SSS_PAM_CHAUTHTOK); + } + + overwrite_and_free_authtoks(&pi); + + return ret; +} + +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 |