Avoid including libds/common/roles.h in public loadparm.h header.
[obnox/samba/samba-obnox.git] / source4 / auth / ntlm / auth_sam.c
index 87a7d275596c7a829d197cfb769f614644ed13ba..096359c9bf06c441fd2133e1120a03f39338bc79 100644 (file)
@@ -33,6 +33,8 @@
 #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);
 
@@ -127,13 +129,6 @@ static NTSTATUS authsam_password_ok(struct auth4_context *auth_context,
                break;
        }
 
-       if (user_sess_key && user_sess_key->data) {
-               talloc_steal(auth_context, user_sess_key->data);
-       }
-       if (lm_sess_key && lm_sess_key->data) {
-               talloc_steal(auth_context, lm_sess_key->data);
-       }
-
        return NT_STATUS_OK;
 }
 
@@ -142,67 +137,97 @@ static NTSTATUS authsam_password_ok(struct auth4_context *auth_context,
   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(TALLOC_CTX *mem_ctx, struct auth4_context *auth_context,
+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;
 
-       irpc_handle = irpc_binding_handle_by_name(mem_ctx, auth_context->msg_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);
 
-       req = dcerpc_drepl_trigger_repl_secret_r_send(mem_ctx,
+       /*
+        * 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(irpc_handle);
+       TALLOC_FREE(tmp_ctx);
 }
 
 
-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) 
+/*
+ * 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)
 {
-       struct samr_Password *lm_pwd, *nt_pwd;
        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;
 
-       uint16_t acct_flags = samdb_result_acct_flags(auth_context->sam_ctx, mem_ctx, msg, domain_dn);
-       
-       /* Quit if the account was locked out. */
-       if (acct_flags & ACB_AUTOLOCK) {
-               DEBUG(3,("check_sam_security: Account for user %s was locked out.\n", 
-                        user_info->mapped.account_name));
-               return NT_STATUS_ACCOUNT_LOCKED_OUT;
+       tmp_ctx = talloc_new(mem_ctx);
+       if (tmp_ctx == NULL) {
+               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)) {
-                       return NT_STATUS_NO_SUCH_USER;
-               }
+       /*
+        * 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;
        }
 
-       nt_status = samdb_result_passwords(mem_ctx, auth_context->lp_ctx, msg, &lm_pwd, &nt_pwd);
-       NT_STATUS_NOT_OK_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
+                       /*
+                        * 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
@@ -213,24 +238,314 @@ static NTSTATUS authsam_authenticate(struct auth4_context *auth_context,
                         * drepl server to tell it to try and
                         * replicate the secrets for this account.
                         */
-                       auth_sam_trigger_repl_secret(mem_ctx, auth_context, msg->dn);
+                       auth_sam_trigger_repl_secret(auth_context, msg->dn);
+                       TALLOC_FREE(tmp_ctx);
                        return NT_STATUS_NOT_IMPLEMENTED;
                }
        }
 
-       nt_status = authsam_password_ok(auth_context, mem_ctx, 
-                                       acct_flags, lm_pwd, nt_pwd,
-                                       user_info, user_sess_key, lm_sess_key);
-       NT_STATUS_NOT_OK_RETURN(nt_status);
+       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;
+}
 
-       nt_status = authsam_account_ok(mem_ctx, auth_context->sam_ctx,
+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;
 }
 
@@ -341,7 +656,7 @@ static NTSTATUS authsam_want_check(struct auth_method_context *ctx,
                        }
                        return NT_STATUS_OK;
 
-               case ROLE_DOMAIN_CONTROLLER:
+               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));
@@ -367,20 +682,21 @@ static NTSTATUS authsam_get_user_info_dc_principal_wrapper(TALLOC_CTX *mem_ctx,
 }
 static const struct auth_operations sam_ignoredomain_ops = {
        .name                      = "sam_ignoredomain",
-       .get_challenge             = auth_get_challenge_not_implemented,
        .want_check                = authsam_ignoredomain_want_check,
        .check_password            = authsam_check_password_internals,
-       .get_user_info_dc_principal = authsam_get_user_info_dc_principal_wrapper
+       .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",
-       .get_challenge             = auth_get_challenge_not_implemented,
        .want_check                = authsam_want_check,
        .check_password            = authsam_check_password_internals,
-       .get_user_info_dc_principal = authsam_get_user_info_dc_principal_wrapper
+       .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;