/* Unix SMB/CIFS implementation. Password and authentication handling Copyright (C) Andrew Bartlett 2001-2009 Copyright (C) Gerald Carter 2003 Copyright (C) Stefan Metzmacher 2005 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 . */ #include "includes.h" #include "system/time.h" #include #include "libcli/ldap/ldap_ndr.h" #include "libcli/security/security.h" #include "auth/auth.h" #include "../libcli/auth/ntlm_check.h" #include "auth/ntlm/auth_proto.h" #include "auth/auth_sam.h" #include "dsdb/samdb/samdb.h" #include "dsdb/common/util.h" #include "param/param.h" #include "librpc/gen_ndr/ndr_irpc_c.h" #include "lib/messaging/irpc.h" #include "libcli/auth/libcli_auth.h" #include "libds/common/roles.h" NTSTATUS auth_sam_init(void); extern const char *user_attrs[]; extern const char *domain_ref_attrs[]; /**************************************************************************** Look for the specified user in the sam, return ldb result structures ****************************************************************************/ static NTSTATUS authsam_search_account(TALLOC_CTX *mem_ctx, struct ldb_context *sam_ctx, const char *account_name, struct ldb_dn *domain_dn, struct ldb_message **ret_msg) { int ret; /* pull the user attributes */ ret = dsdb_search_one(sam_ctx, mem_ctx, ret_msg, domain_dn, LDB_SCOPE_SUBTREE, user_attrs, DSDB_SEARCH_SHOW_EXTENDED_DN, "(&(sAMAccountName=%s)(objectclass=user))", ldb_binary_encode_string(mem_ctx, account_name)); if (ret == LDB_ERR_NO_SUCH_OBJECT) { DEBUG(3,("sam_search_user: Couldn't find user [%s] in samdb, under %s\n", account_name, ldb_dn_get_linearized(domain_dn))); return NT_STATUS_NO_SUCH_USER; } if (ret != LDB_SUCCESS) { return NT_STATUS_INTERNAL_DB_CORRUPTION; } return NT_STATUS_OK; } /**************************************************************************** Do a specific test for an smb password being correct, given a smb_password and the lanman and NT responses. ****************************************************************************/ static NTSTATUS authsam_password_ok(struct auth4_context *auth_context, TALLOC_CTX *mem_ctx, uint16_t acct_flags, const struct samr_Password *lm_pwd, const struct samr_Password *nt_pwd, const struct auth_usersupplied_info *user_info, DATA_BLOB *user_sess_key, DATA_BLOB *lm_sess_key) { NTSTATUS status; switch (user_info->password_state) { case AUTH_PASSWORD_PLAIN: { const struct auth_usersupplied_info *user_info_temp; status = encrypt_user_info(mem_ctx, auth_context, AUTH_PASSWORD_HASH, user_info, &user_info_temp); if (!NT_STATUS_IS_OK(status)) { DEBUG(1, ("Failed to convert plaintext password to password HASH: %s\n", nt_errstr(status))); return status; } user_info = user_info_temp; /*fall through*/ } case AUTH_PASSWORD_HASH: *lm_sess_key = data_blob(NULL, 0); *user_sess_key = data_blob(NULL, 0); status = hash_password_check(mem_ctx, lpcfg_lanman_auth(auth_context->lp_ctx), user_info->password.hash.lanman, user_info->password.hash.nt, user_info->mapped.account_name, lm_pwd, nt_pwd); NT_STATUS_NOT_OK_RETURN(status); break; case AUTH_PASSWORD_RESPONSE: status = ntlm_password_check(mem_ctx, lpcfg_lanman_auth(auth_context->lp_ctx), lpcfg_ntlm_auth(auth_context->lp_ctx), user_info->logon_parameters, &auth_context->challenge.data, &user_info->password.response.lanman, &user_info->password.response.nt, user_info->mapped.account_name, user_info->client.account_name, user_info->client.domain_name, lm_pwd, nt_pwd, user_sess_key, lm_sess_key); NT_STATUS_NOT_OK_RETURN(status); break; } return NT_STATUS_OK; } /* send a message to the drepl server telling it to initiate a REPL_SECRET getncchanges extended op to fetch the users secrets */ static void auth_sam_trigger_repl_secret(struct auth4_context *auth_context, struct ldb_dn *user_dn) { struct dcerpc_binding_handle *irpc_handle; struct drepl_trigger_repl_secret r; struct tevent_req *req; TALLOC_CTX *tmp_ctx; tmp_ctx = talloc_new(auth_context); if (tmp_ctx == NULL) { return; } irpc_handle = irpc_binding_handle_by_name(tmp_ctx, auth_context->msg_ctx, "dreplsrv", &ndr_table_irpc); if (irpc_handle == NULL) { DEBUG(1,(__location__ ": Unable to get binding handle for dreplsrv\n")); TALLOC_FREE(tmp_ctx); return; } r.in.user_dn = ldb_dn_get_linearized(user_dn); /* * This seem to rely on the current IRPC implementation, * which delivers the message in the _send function. * * TODO: we need a ONE_WAY IRPC handle and register * a callback and wait for it to be triggered! */ req = dcerpc_drepl_trigger_repl_secret_r_send(tmp_ctx, auth_context->event_ctx, irpc_handle, &r); /* we aren't interested in a reply */ talloc_free(req); TALLOC_FREE(tmp_ctx); } /* * Check that a password is OK, and update badPwdCount if required. */ static NTSTATUS authsam_password_check_and_record(struct auth4_context *auth_context, TALLOC_CTX *mem_ctx, struct ldb_dn *domain_dn, struct ldb_message *msg, uint16_t acct_flags, const struct auth_usersupplied_info *user_info, DATA_BLOB *user_sess_key, DATA_BLOB *lm_sess_key) { NTSTATUS nt_status; NTSTATUS auth_status; TALLOC_CTX *tmp_ctx; int i, ret; int history_len = 0; struct ldb_context *sam_ctx = auth_context->sam_ctx; const char * const attrs[] = { "pwdHistoryLength", NULL }; struct ldb_message *dom_msg; struct samr_Password *lm_pwd; struct samr_Password *nt_pwd; tmp_ctx = talloc_new(mem_ctx); if (tmp_ctx == NULL) { return NT_STATUS_NO_MEMORY; } /* * This call does more than what it appears to do, it also * checks for the account lockout. * * It is done here so that all parts of Samba that read the * password refuse to even operate on it if the account is * locked out, to avoid mistakes like CVE-2013-4496. */ nt_status = samdb_result_passwords(tmp_ctx, auth_context->lp_ctx, msg, &lm_pwd, &nt_pwd); if (!NT_STATUS_IS_OK(nt_status)) { TALLOC_FREE(tmp_ctx); return nt_status; } if (lm_pwd == NULL && nt_pwd == NULL) { bool am_rodc; if (samdb_rodc(auth_context->sam_ctx, &am_rodc) == LDB_SUCCESS && am_rodc) { /* * we don't have passwords for this * account. We are an RODC, and this account * may be one for which we either are denied * REPL_SECRET replication or we haven't yet * done the replication. We return * NT_STATUS_NOT_IMPLEMENTED which tells the * auth code to try the next authentication * mechanism. We also send a message to our * drepl server to tell it to try and * replicate the secrets for this account. */ auth_sam_trigger_repl_secret(auth_context, msg->dn); TALLOC_FREE(tmp_ctx); return NT_STATUS_NOT_IMPLEMENTED; } } auth_status = authsam_password_ok(auth_context, tmp_ctx, acct_flags, lm_pwd, nt_pwd, user_info, user_sess_key, lm_sess_key); if (NT_STATUS_IS_OK(auth_status)) { if (user_sess_key->data) { talloc_steal(mem_ctx, user_sess_key->data); } if (lm_sess_key->data) { talloc_steal(mem_ctx, lm_sess_key->data); } TALLOC_FREE(tmp_ctx); return NT_STATUS_OK; } *user_sess_key = data_blob_null; *lm_sess_key = data_blob_null; if (!NT_STATUS_EQUAL(auth_status, NT_STATUS_WRONG_PASSWORD)) { TALLOC_FREE(tmp_ctx); return auth_status; } /* * We only continue if this was a wrong password * and we'll always return NT_STATUS_WRONG_PASSWORD * no matter what error happens. */ /* pull the domain password property attributes */ ret = dsdb_search_one(sam_ctx, tmp_ctx, &dom_msg, domain_dn, LDB_SCOPE_BASE, attrs, 0, "objectClass=domain"); if (ret == LDB_SUCCESS) { history_len = ldb_msg_find_attr_as_uint(dom_msg, "pwdHistoryLength", 0); } else if (ret == LDB_ERR_NO_SUCH_OBJECT) { DEBUG(3,("Couldn't find domain %s: %s!\n", ldb_dn_get_linearized(domain_dn), ldb_errstring(sam_ctx))); } else { DEBUG(3,("error finding domain %s: %s!\n", ldb_dn_get_linearized(domain_dn), ldb_errstring(sam_ctx))); } for (i = 1; i < MIN(history_len, 3); i++) { static const struct samr_Password zero_hash; struct samr_Password zero_string_hash; struct samr_Password zero_string_des_hash; struct samr_Password *nt_history_pwd = NULL; struct samr_Password *lm_history_pwd = NULL; NTTIME pwdLastSet; struct timeval tv_now; NTTIME now; int allowed_period_mins; NTTIME allowed_period; nt_status = samdb_result_passwords_from_history(tmp_ctx, auth_context->lp_ctx, msg, i, &lm_history_pwd, &nt_history_pwd); if (!NT_STATUS_IS_OK(nt_status)) { /* * If we don't find element 'i' we won't find * 'i+1' ... */ break; } /* * We choose to avoid any issues * around different LM and NT history * lengths by only checking the NT * history */ if (nt_history_pwd == NULL) { /* * If we don't find element 'i' we won't find * 'i+1' ... */ break; } /* Skip over all-zero hashes in the history */ if (memcmp(nt_history_pwd->hash, zero_hash.hash, sizeof(zero_hash.hash)) == 0) { continue; } /* * This looks odd, but the password_hash module writes this in if * (somehow) we didn't have an old NT hash */ E_md4hash("", zero_string_hash.hash); if (memcmp(nt_history_pwd->hash, zero_string_hash.hash, 16) == 0) { continue; } E_deshash("", zero_string_des_hash.hash); if (!lm_history_pwd || memcmp(lm_history_pwd->hash, zero_string_des_hash.hash, 16) == 0) { lm_history_pwd = NULL; } auth_status = authsam_password_ok(auth_context, tmp_ctx, acct_flags, lm_history_pwd, nt_history_pwd, user_info, user_sess_key, lm_sess_key); if (!NT_STATUS_IS_OK(auth_status)) { /* * If this was not a correct password, try the next * one from the history */ *user_sess_key = data_blob_null; *lm_sess_key = data_blob_null; continue; } if (i != 1) { /* * The authentication was OK, but not against * the previous password, which is stored at index 1. * * We just return the original wrong password. * This skips the update of the bad pwd count, * because this is almost certainly user error * (or automatic login on a computer using a cached * password from before the password change), * not an attack. */ TALLOC_FREE(tmp_ctx); return NT_STATUS_WRONG_PASSWORD; } if (user_info->password_state != AUTH_PASSWORD_RESPONSE) { /* * The authentication was OK against the previous password, * but it's not a NTLM network authentication. * * We just return the original wrong password. * This skips the update of the bad pwd count, * because this is almost certainly user error * (or automatic login on a computer using a cached * password from before the password change), * not an attack. */ TALLOC_FREE(tmp_ctx); return NT_STATUS_WRONG_PASSWORD; } /* * If the password was OK, it's a NTLM network authentication * and it was the previous password. * * Now we see if it is within the grace period, * so that we don't break cached sessions on other computers * before the user can lock and unlock their other screens * (resetting their cached password). * * See http://support.microsoft.com/kb/906305 * OldPasswordAllowedPeriod ("old password allowed period") * is specified in minutes. The default is 60. */ allowed_period_mins = lpcfg_old_password_allowed_period(auth_context->lp_ctx); /* * NTTIME uses 100ns units */ allowed_period = allowed_period_mins * 60 * 1000*1000*10; pwdLastSet = samdb_result_nttime(msg, "pwdLastSet", 0); tv_now = timeval_current(); now = timeval_to_nttime(&tv_now); if (now < pwdLastSet) { /* * time jump? * * We just return the original wrong password. * This skips the update of the bad pwd count, * because this is almost certainly user error * (or automatic login on a computer using a cached * password from before the password change), * not an attack. */ TALLOC_FREE(tmp_ctx); return NT_STATUS_WRONG_PASSWORD; } if ((now - pwdLastSet) >= allowed_period) { /* * The allowed period is over. * * We just return the original wrong password. * This skips the update of the bad pwd count, * because this is almost certainly user error * (or automatic login on a computer using a cached * password from before the password change), * not an attack. */ TALLOC_FREE(tmp_ctx); return NT_STATUS_WRONG_PASSWORD; } /* * We finally allow the authentication with the * previous password within the allowed period. */ if (user_sess_key->data) { talloc_steal(mem_ctx, user_sess_key->data); } if (lm_sess_key->data) { talloc_steal(mem_ctx, lm_sess_key->data); } TALLOC_FREE(tmp_ctx); return auth_status; } /* * If we are not in the allowed period or match an old password, * we didn't return early. Now update the badPwdCount et al. */ nt_status = authsam_update_bad_pwd_count(auth_context->sam_ctx, msg, domain_dn); if (!NT_STATUS_IS_OK(nt_status)) { /* * We need to return the original * NT_STATUS_WRONG_PASSWORD error, so there isn't * anything more we can do than write something into * the log */ DEBUG(0, ("Failed to note bad password for user [%s]: %s\n", user_info->mapped.account_name, nt_errstr(nt_status))); } TALLOC_FREE(tmp_ctx); return NT_STATUS_WRONG_PASSWORD; } static NTSTATUS authsam_authenticate(struct auth4_context *auth_context, TALLOC_CTX *mem_ctx, struct ldb_context *sam_ctx, struct ldb_dn *domain_dn, struct ldb_message *msg, const struct auth_usersupplied_info *user_info, DATA_BLOB *user_sess_key, DATA_BLOB *lm_sess_key) { NTSTATUS nt_status; bool interactive = (user_info->password_state == AUTH_PASSWORD_HASH); uint16_t acct_flags = samdb_result_acct_flags(msg, NULL); TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); if (!tmp_ctx) { return NT_STATUS_NO_MEMORY; } /* You can only do an interactive login to normal accounts */ if (user_info->flags & USER_INFO_INTERACTIVE_LOGON) { if (!(acct_flags & ACB_NORMAL)) { TALLOC_FREE(tmp_ctx); return NT_STATUS_NO_SUCH_USER; } } nt_status = authsam_password_check_and_record(auth_context, tmp_ctx, domain_dn, msg, acct_flags, user_info, user_sess_key, lm_sess_key); if (!NT_STATUS_IS_OK(nt_status)) { TALLOC_FREE(tmp_ctx); return nt_status; } nt_status = authsam_account_ok(tmp_ctx, auth_context->sam_ctx, user_info->logon_parameters, domain_dn, msg, user_info->workstation_name, user_info->mapped.account_name, false, false); if (!NT_STATUS_IS_OK(nt_status)) { TALLOC_FREE(tmp_ctx); return nt_status; } nt_status = authsam_logon_success_accounting(auth_context->sam_ctx, msg, domain_dn, interactive); if (!NT_STATUS_IS_OK(nt_status)) { TALLOC_FREE(tmp_ctx); return nt_status; } if (user_sess_key && user_sess_key->data) { talloc_steal(mem_ctx, user_sess_key->data); } if (lm_sess_key && lm_sess_key->data) { talloc_steal(mem_ctx, lm_sess_key->data); } TALLOC_FREE(tmp_ctx); return nt_status; } static NTSTATUS authsam_check_password_internals(struct auth_method_context *ctx, TALLOC_CTX *mem_ctx, const struct auth_usersupplied_info *user_info, struct auth_user_info_dc **user_info_dc) { NTSTATUS nt_status; const char *account_name = user_info->mapped.account_name; struct ldb_message *msg; struct ldb_dn *domain_dn; DATA_BLOB user_sess_key, lm_sess_key; TALLOC_CTX *tmp_ctx; if (ctx->auth_ctx->sam_ctx == NULL) { DEBUG(0, ("No SAM available, cannot log in users\n")); return NT_STATUS_INVALID_SYSTEM_SERVICE; } if (!account_name || !*account_name) { /* 'not for me' */ return NT_STATUS_NOT_IMPLEMENTED; } tmp_ctx = talloc_new(mem_ctx); if (!tmp_ctx) { return NT_STATUS_NO_MEMORY; } domain_dn = ldb_get_default_basedn(ctx->auth_ctx->sam_ctx); if (domain_dn == NULL) { talloc_free(tmp_ctx); return NT_STATUS_NO_SUCH_DOMAIN; } nt_status = authsam_search_account(tmp_ctx, ctx->auth_ctx->sam_ctx, account_name, domain_dn, &msg); if (!NT_STATUS_IS_OK(nt_status)) { talloc_free(tmp_ctx); return nt_status; } nt_status = authsam_authenticate(ctx->auth_ctx, tmp_ctx, ctx->auth_ctx->sam_ctx, domain_dn, msg, user_info, &user_sess_key, &lm_sess_key); if (!NT_STATUS_IS_OK(nt_status)) { talloc_free(tmp_ctx); return nt_status; } nt_status = authsam_make_user_info_dc(tmp_ctx, ctx->auth_ctx->sam_ctx, lpcfg_netbios_name(ctx->auth_ctx->lp_ctx), lpcfg_sam_name(ctx->auth_ctx->lp_ctx), domain_dn, msg, user_sess_key, lm_sess_key, user_info_dc); if (!NT_STATUS_IS_OK(nt_status)) { talloc_free(tmp_ctx); return nt_status; } talloc_steal(mem_ctx, *user_info_dc); talloc_free(tmp_ctx); return NT_STATUS_OK; } static NTSTATUS authsam_ignoredomain_want_check(struct auth_method_context *ctx, TALLOC_CTX *mem_ctx, const struct auth_usersupplied_info *user_info) { if (!user_info->mapped.account_name || !*user_info->mapped.account_name) { return NT_STATUS_NOT_IMPLEMENTED; } return NT_STATUS_OK; } /**************************************************************************** Check SAM security (above) but with a few extra checks. ****************************************************************************/ static NTSTATUS authsam_want_check(struct auth_method_context *ctx, TALLOC_CTX *mem_ctx, const struct auth_usersupplied_info *user_info) { bool is_local_name, is_my_domain; if (!user_info->mapped.account_name || !*user_info->mapped.account_name) { return NT_STATUS_NOT_IMPLEMENTED; } is_local_name = lpcfg_is_myname(ctx->auth_ctx->lp_ctx, user_info->mapped.domain_name); is_my_domain = lpcfg_is_mydomain(ctx->auth_ctx->lp_ctx, user_info->mapped.domain_name); /* check whether or not we service this domain/workgroup name */ switch (lpcfg_server_role(ctx->auth_ctx->lp_ctx)) { case ROLE_STANDALONE: return NT_STATUS_OK; case ROLE_DOMAIN_MEMBER: if (!is_local_name) { DEBUG(6,("authsam_check_password: %s is not one of my local names (DOMAIN_MEMBER)\n", user_info->mapped.domain_name)); return NT_STATUS_NOT_IMPLEMENTED; } return NT_STATUS_OK; case ROLE_ACTIVE_DIRECTORY_DC: if (!is_local_name && !is_my_domain) { DEBUG(6,("authsam_check_password: %s is not one of my local names or domain name (DC)\n", user_info->mapped.domain_name)); return NT_STATUS_NOT_IMPLEMENTED; } return NT_STATUS_OK; } DEBUG(6,("authsam_check_password: lpcfg_server_role() has an undefined value\n")); return NT_STATUS_NOT_IMPLEMENTED; } /* Wrapper for the auth subsystem pointer */ static NTSTATUS authsam_get_user_info_dc_principal_wrapper(TALLOC_CTX *mem_ctx, struct auth4_context *auth_context, const char *principal, struct ldb_dn *user_dn, struct auth_user_info_dc **user_info_dc) { return authsam_get_user_info_dc_principal(mem_ctx, auth_context->lp_ctx, auth_context->sam_ctx, principal, user_dn, user_info_dc); } static const struct auth_operations sam_ignoredomain_ops = { .name = "sam_ignoredomain", .want_check = authsam_ignoredomain_want_check, .check_password = authsam_check_password_internals, .get_user_info_dc_principal = authsam_get_user_info_dc_principal_wrapper, .flags = AUTH_METHOD_LOCAL_SAM }; static const struct auth_operations sam_ops = { .name = "sam", .want_check = authsam_want_check, .check_password = authsam_check_password_internals, .get_user_info_dc_principal = authsam_get_user_info_dc_principal_wrapper, .flags = AUTH_METHOD_LOCAL_SAM }; _PUBLIC_ NTSTATUS auth4_sam_init(void); _PUBLIC_ NTSTATUS auth4_sam_init(void) { NTSTATUS ret; ret = auth_register(&sam_ops); if (!NT_STATUS_IS_OK(ret)) { DEBUG(0,("Failed to register 'sam' auth backend!\n")); return ret; } ret = auth_register(&sam_ignoredomain_ops); if (!NT_STATUS_IS_OK(ret)) { DEBUG(0,("Failed to register 'sam_ignoredomain' auth backend!\n")); return ret; } return ret; }