diff options
Diffstat (limited to 'bin/named/controlconf.c')
| -rw-r--r-- | bin/named/controlconf.c | 1530 |
1 files changed, 1530 insertions, 0 deletions
diff --git a/bin/named/controlconf.c b/bin/named/controlconf.c new file mode 100644 index 0000000..d955c2f --- /dev/null +++ b/bin/named/controlconf.c @@ -0,0 +1,1530 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +/*! \file */ + +#include <config.h> + +#include <inttypes.h> +#include <stdbool.h> + +#include <isc/base64.h> +#include <isc/buffer.h> +#include <isc/event.h> +#include <isc/file.h> +#include <isc/mem.h> +#include <isc/net.h> +#include <isc/netaddr.h> +#include <isc/random.h> +#include <isc/result.h> +#include <isc/stdtime.h> +#include <isc/string.h> +#include <isc/timer.h> +#include <isc/util.h> + +#include <isccfg/namedconf.h> + +#include <bind9/check.h> + +#include <isccc/alist.h> +#include <isccc/cc.h> +#include <isccc/ccmsg.h> +#include <isccc/events.h> +#include <isccc/result.h> +#include <isccc/sexpr.h> +#include <isccc/symtab.h> +#include <isccc/util.h> + +#include <dns/result.h> + +#include <named/config.h> +#include <named/control.h> +#include <named/log.h> +#include <named/server.h> + +/* + * Note: Listeners and connections are not locked. All event handlers are + * executed by the server task, and all callers of exported routines must + * be running under the server task. + */ + +typedef struct controlkey controlkey_t; +typedef ISC_LIST(controlkey_t) controlkeylist_t; + +typedef struct controlconnection controlconnection_t; +typedef ISC_LIST(controlconnection_t) controlconnectionlist_t; + +typedef struct controllistener controllistener_t; +typedef ISC_LIST(controllistener_t) controllistenerlist_t; + +struct controlkey { + char * keyname; + uint32_t algorithm; + isc_region_t secret; + ISC_LINK(controlkey_t) link; +}; + +struct controlconnection { + isc_socket_t * sock; + isccc_ccmsg_t ccmsg; + bool ccmsg_valid; + bool sending; + isc_timer_t * timer; + isc_buffer_t * buffer; + controllistener_t * listener; + uint32_t nonce; + ISC_LINK(controlconnection_t) link; +}; + +struct controllistener { + ns_controls_t * controls; + isc_mem_t * mctx; + isc_task_t * task; + isc_sockaddr_t address; + isc_socket_t * sock; + dns_acl_t * acl; + bool listening; + bool exiting; + controlkeylist_t keys; + controlconnectionlist_t connections; + isc_sockettype_t type; + uint32_t perm; + uint32_t owner; + uint32_t group; + bool readonly; + ISC_LINK(controllistener_t) link; +}; + +struct ns_controls { + ns_server_t *server; + controllistenerlist_t listeners; + bool shuttingdown; + isccc_symtab_t *symtab; +}; + +static void control_newconn(isc_task_t *task, isc_event_t *event); +static void control_recvmessage(isc_task_t *task, isc_event_t *event); + +#define CLOCKSKEW 300 + +static void +free_controlkey(controlkey_t *key, isc_mem_t *mctx) { + if (key->keyname != NULL) + isc_mem_free(mctx, key->keyname); + if (key->secret.base != NULL) + isc_mem_put(mctx, key->secret.base, key->secret.length); + isc_mem_put(mctx, key, sizeof(*key)); +} + +static void +free_controlkeylist(controlkeylist_t *keylist, isc_mem_t *mctx) { + while (!ISC_LIST_EMPTY(*keylist)) { + controlkey_t *key = ISC_LIST_HEAD(*keylist); + ISC_LIST_UNLINK(*keylist, key, link); + free_controlkey(key, mctx); + } +} + +static void +free_listener(controllistener_t *listener) { + INSIST(listener->exiting); + INSIST(!listener->listening); + INSIST(ISC_LIST_EMPTY(listener->connections)); + + if (listener->sock != NULL) + isc_socket_detach(&listener->sock); + + free_controlkeylist(&listener->keys, listener->mctx); + + if (listener->acl != NULL) + dns_acl_detach(&listener->acl); + + isc_mem_putanddetach(&listener->mctx, listener, sizeof(*listener)); +} + +static void +maybe_free_listener(controllistener_t *listener) { + if (listener->exiting && + !listener->listening && + ISC_LIST_EMPTY(listener->connections)) + free_listener(listener); +} + +static void +maybe_free_connection(controlconnection_t *conn) { + controllistener_t *listener = conn->listener; + + if (conn->buffer != NULL) + isc_buffer_free(&conn->buffer); + + if (conn->timer != NULL) + isc_timer_detach(&conn->timer); + + if (conn->ccmsg_valid) { + isccc_ccmsg_cancelread(&conn->ccmsg); + return; + } + + if (conn->sending) { + isc_socket_cancel(conn->sock, listener->task, + ISC_SOCKCANCEL_SEND); + return; + } + + ISC_LIST_UNLINK(listener->connections, conn, link); +#ifdef ENABLE_AFL + if (ns_g_fuzz_type == ns_fuzz_rndc) { + named_fuzz_notify(); + } +#endif + isc_mem_put(listener->mctx, conn, sizeof(*conn)); +} + +static void +shutdown_listener(controllistener_t *listener) { + controlconnection_t *conn; + controlconnection_t *next; + + if (!listener->exiting) { + char socktext[ISC_SOCKADDR_FORMATSIZE]; + + ISC_LIST_UNLINK(listener->controls->listeners, listener, link); + + isc_sockaddr_format(&listener->address, socktext, + sizeof(socktext)); + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE, + "stopping command channel on %s", socktext); + if (listener->type == isc_sockettype_unix) + isc_socket_cleanunix(&listener->address, true); + listener->exiting = true; + } + + for (conn = ISC_LIST_HEAD(listener->connections); + conn != NULL; + conn = next) + { + next = ISC_LIST_NEXT(conn, link); + maybe_free_connection(conn); + } + + if (listener->listening) + isc_socket_cancel(listener->sock, listener->task, + ISC_SOCKCANCEL_ACCEPT); + + maybe_free_listener(listener); +} + +static bool +address_ok(isc_sockaddr_t *sockaddr, dns_acl_t *acl) { + isc_netaddr_t netaddr; + isc_result_t result; + int match; + + isc_netaddr_fromsockaddr(&netaddr, sockaddr); + + result = dns_acl_match(&netaddr, NULL, acl, + &ns_g_server->aclenv, &match, NULL); + + if (result != ISC_R_SUCCESS || match <= 0) + return (false); + else + return (true); +} + +static isc_result_t +control_accept(controllistener_t *listener) { + isc_result_t result; + result = isc_socket_accept(listener->sock, + listener->task, + control_newconn, listener); + if (result != ISC_R_SUCCESS) + UNEXPECTED_ERROR(__FILE__, __LINE__, + "isc_socket_accept() failed: %s", + isc_result_totext(result)); + else + listener->listening = true; + return (result); +} + +static isc_result_t +control_listen(controllistener_t *listener) { + isc_result_t result; + + result = isc_socket_listen(listener->sock, 0); + if (result != ISC_R_SUCCESS) + UNEXPECTED_ERROR(__FILE__, __LINE__, + "isc_socket_listen() failed: %s", + isc_result_totext(result)); + return (result); +} + +static void +control_next(controllistener_t *listener) { + (void)control_accept(listener); +} + +static void +control_senddone(isc_task_t *task, isc_event_t *event) { + isc_socketevent_t *sevent = (isc_socketevent_t *) event; + controlconnection_t *conn = event->ev_arg; + controllistener_t *listener = conn->listener; + isc_socket_t *sock = (isc_socket_t *)sevent->ev_sender; + isc_result_t result; + + REQUIRE(conn->sending); + + UNUSED(task); + + conn->sending = false; + + if (sevent->result != ISC_R_SUCCESS && + sevent->result != ISC_R_CANCELED) + { + char socktext[ISC_SOCKADDR_FORMATSIZE]; + isc_sockaddr_t peeraddr; + + (void)isc_socket_getpeername(sock, &peeraddr); + isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext)); + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_WARNING, + "error sending command response to %s: %s", + socktext, isc_result_totext(sevent->result)); + } + isc_event_free(&event); + + result = isccc_ccmsg_readmessage(&conn->ccmsg, listener->task, + control_recvmessage, conn); + if (result != ISC_R_SUCCESS) { + isc_socket_detach(&conn->sock); + maybe_free_connection(conn); + maybe_free_listener(listener); + } +} + +static inline void +log_invalid(isccc_ccmsg_t *ccmsg, isc_result_t result) { + char socktext[ISC_SOCKADDR_FORMATSIZE]; + isc_sockaddr_t peeraddr; + + (void)isc_socket_getpeername(ccmsg->sock, &peeraddr); + isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext)); + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_ERROR, + "invalid command from %s: %s", + socktext, isc_result_totext(result)); +} + +static void +control_recvmessage(isc_task_t *task, isc_event_t *event) { + controlconnection_t *conn; + controllistener_t *listener; + controlkey_t *key; + isccc_sexpr_t *request = NULL; + isccc_sexpr_t *response = NULL; + uint32_t algorithm; + isccc_region_t secret; + isc_stdtime_t now; + isc_buffer_t b; + isc_region_t r; + isc_buffer_t *text; + isc_result_t result; + isc_result_t eresult; + isccc_sexpr_t *_ctrl; + isccc_time_t sent; + isccc_time_t exp; + uint32_t nonce; + isccc_sexpr_t *data; + + REQUIRE(event->ev_type == ISCCC_EVENT_CCMSG); + + conn = event->ev_arg; + listener = conn->listener; + algorithm = DST_ALG_UNKNOWN; + secret.rstart = NULL; + text = NULL; + + /* Is the server shutting down? */ + if (listener->controls->shuttingdown) + goto cleanup; + + if (conn->ccmsg.result != ISC_R_SUCCESS) { + if (conn->ccmsg.result != ISC_R_CANCELED && + conn->ccmsg.result != ISC_R_EOF) + log_invalid(&conn->ccmsg, conn->ccmsg.result); + goto cleanup; + } + + request = NULL; + + for (key = ISC_LIST_HEAD(listener->keys); + key != NULL; + key = ISC_LIST_NEXT(key, link)) + { + isccc_region_t ccregion; + + ccregion.rstart = isc_buffer_base(&conn->ccmsg.buffer); + ccregion.rend = isc_buffer_used(&conn->ccmsg.buffer); + secret.rstart = isc_mem_get(listener->mctx, key->secret.length); + if (secret.rstart == NULL) + goto cleanup; + memmove(secret.rstart, key->secret.base, key->secret.length); + secret.rend = secret.rstart + key->secret.length; + algorithm = key->algorithm; + result = isccc_cc_fromwire(&ccregion, &request, + algorithm, &secret); + if (result == ISC_R_SUCCESS) + break; + isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret)); + if (result != ISCCC_R_BADAUTH) { + log_invalid(&conn->ccmsg, result); + goto cleanup; + } + } + + if (key == NULL) { + log_invalid(&conn->ccmsg, ISCCC_R_BADAUTH); + goto cleanup; + } + + /* We shouldn't be getting a reply. */ + if (isccc_cc_isreply(request)) { + log_invalid(&conn->ccmsg, ISC_R_FAILURE); + goto cleanup_request; + } + + isc_stdtime_get(&now); + + /* + * Limit exposure to replay attacks. + */ + _ctrl = isccc_alist_lookup(request, "_ctrl"); + if (!isccc_alist_alistp(_ctrl)) { + log_invalid(&conn->ccmsg, ISC_R_FAILURE); + goto cleanup_request; + } + + if (isccc_cc_lookupuint32(_ctrl, "_tim", &sent) == ISC_R_SUCCESS) { + if ((sent + CLOCKSKEW) < now || (sent - CLOCKSKEW) > now) { + log_invalid(&conn->ccmsg, ISCCC_R_CLOCKSKEW); + goto cleanup_request; + } + } else { + log_invalid(&conn->ccmsg, ISC_R_FAILURE); + goto cleanup_request; + } + + /* + * Expire messages that are too old. + */ + if (isccc_cc_lookupuint32(_ctrl, "_exp", &exp) == ISC_R_SUCCESS && + now > exp) { + log_invalid(&conn->ccmsg, ISCCC_R_EXPIRED); + goto cleanup_request; + } + + /* + * Duplicate suppression (required for UDP). + */ + isccc_cc_cleansymtab(listener->controls->symtab, now); + result = isccc_cc_checkdup(listener->controls->symtab, request, now); + if (result != ISC_R_SUCCESS) { + if (result == ISC_R_EXISTS) + result = ISCCC_R_DUPLICATE; + log_invalid(&conn->ccmsg, result); + goto cleanup_request; + } + + if (conn->nonce != 0 && + (isccc_cc_lookupuint32(_ctrl, "_nonce", &nonce) != ISC_R_SUCCESS || + conn->nonce != nonce)) { + log_invalid(&conn->ccmsg, ISCCC_R_BADAUTH); + goto cleanup_request; + } + + result = isc_buffer_allocate(listener->mctx, &text, 2 * 2048); + if (result != ISC_R_SUCCESS) + goto cleanup_request; + + /* + * Establish nonce. + */ + if (conn->nonce == 0) { + while (conn->nonce == 0) + isc_random_get(&conn->nonce); + eresult = ISC_R_SUCCESS; + } else + eresult = ns_control_docommand(request, listener->readonly, &text); + + result = isccc_cc_createresponse(request, now, now + 60, &response); + if (result != ISC_R_SUCCESS) + goto cleanup_request; + + data = isccc_alist_lookup(response, "_data"); + if (data != NULL) { + if (isccc_cc_defineuint32(data, "result", eresult) == NULL) + goto cleanup_response; + } + + if (eresult != ISC_R_SUCCESS) { + if (data != NULL) { + const char *estr = isc_result_totext(eresult); + if (isccc_cc_definestring(data, "err", estr) == NULL) + goto cleanup_response; + } + } + + if (isc_buffer_usedlength(text) > 0) { + if (data != NULL) { + char *str = (char *)isc_buffer_base(text); + if (isccc_cc_definestring(data, "text", str) == NULL) + goto cleanup_response; + } + } + + _ctrl = isccc_alist_lookup(response, "_ctrl"); + if (_ctrl == NULL || + isccc_cc_defineuint32(_ctrl, "_nonce", conn->nonce) == NULL) + goto cleanup_response; + + if (conn->buffer == NULL) { + result = isc_buffer_allocate(listener->mctx, + &conn->buffer, 2 * 2048); + if (result != ISC_R_SUCCESS) + goto cleanup_response; + } + + isc_buffer_clear(conn->buffer); + /* Skip the length field (4 bytes) */ + isc_buffer_add(conn->buffer, 4); + + result = isccc_cc_towire(response, &conn->buffer, algorithm, &secret); + if (result != ISC_R_SUCCESS) + goto cleanup_response; + + isc_buffer_init(&b, conn->buffer->base, 4); + isc_buffer_putuint32(&b, conn->buffer->used - 4); + + r.base = conn->buffer->base; + r.length = conn->buffer->used; + + result = isc_socket_send(conn->sock, &r, task, control_senddone, conn); + if (result != ISC_R_SUCCESS) + goto cleanup_response; + conn->sending = true; + + isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret)); + isccc_sexpr_free(&request); + isccc_sexpr_free(&response); + isc_buffer_free(&text); + return; + + cleanup_response: + isccc_sexpr_free(&response); + + cleanup_request: + isccc_sexpr_free(&request); + isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret)); + if (text != NULL) + isc_buffer_free(&text); + + cleanup: + isc_socket_detach(&conn->sock); + isccc_ccmsg_invalidate(&conn->ccmsg); + conn->ccmsg_valid = false; + maybe_free_connection(conn); + maybe_free_listener(listener); +} + +static void +control_timeout(isc_task_t *task, isc_event_t *event) { + controlconnection_t *conn = event->ev_arg; + + UNUSED(task); + + isc_timer_detach(&conn->timer); + maybe_free_connection(conn); + + isc_event_free(&event); +} + +static isc_result_t +newconnection(controllistener_t *listener, isc_socket_t *sock) { + controlconnection_t *conn; + isc_interval_t interval; + isc_result_t result; + + conn = isc_mem_get(listener->mctx, sizeof(*conn)); + if (conn == NULL) + return (ISC_R_NOMEMORY); + + conn->sock = sock; + isccc_ccmsg_init(listener->mctx, sock, &conn->ccmsg); + + /* Set a 32 KiB upper limit on incoming message. */ + isccc_ccmsg_setmaxsize(&conn->ccmsg, 32768); + + conn->ccmsg_valid = true; + conn->sending = false; + conn->buffer = NULL; + conn->timer = NULL; + isc_interval_set(&interval, 60, 0); + result = isc_timer_create(ns_g_timermgr, isc_timertype_once, + NULL, &interval, listener->task, + control_timeout, conn, &conn->timer); + if (result != ISC_R_SUCCESS) + goto cleanup; + + conn->listener = listener; + conn->nonce = 0; + ISC_LINK_INIT(conn, link); + + result = isccc_ccmsg_readmessage(&conn->ccmsg, listener->task, + control_recvmessage, conn); + if (result != ISC_R_SUCCESS) + goto cleanup; + + ISC_LIST_APPEND(listener->connections, conn, link); + return (ISC_R_SUCCESS); + + cleanup: + if (conn->buffer != NULL) + isc_buffer_free(&conn->buffer); + isccc_ccmsg_invalidate(&conn->ccmsg); + if (conn->timer != NULL) + isc_timer_detach(&conn->timer); + isc_mem_put(listener->mctx, conn, sizeof(*conn)); +#ifdef ENABLE_AFL + if (ns_g_fuzz_type == ns_fuzz_rndc) { + named_fuzz_notify(); + } +#endif + return (result); +} + +static void +control_newconn(isc_task_t *task, isc_event_t *event) { + isc_socket_newconnev_t *nevent = (isc_socket_newconnev_t *)event; + controllistener_t *listener = event->ev_arg; + isc_socket_t *sock; + isc_sockaddr_t peeraddr; + isc_result_t result; + + UNUSED(task); + + listener->listening = false; + + if (nevent->result != ISC_R_SUCCESS) { + if (nevent->result == ISC_R_CANCELED) { + shutdown_listener(listener); + goto cleanup; + } + goto restart; + } + + sock = nevent->newsocket; + isc_socket_setname(sock, "control", NULL); + (void)isc_socket_getpeername(sock, &peeraddr); + if (listener->type == isc_sockettype_tcp && + !address_ok(&peeraddr, listener->acl)) { + char socktext[ISC_SOCKADDR_FORMATSIZE]; + isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext)); + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_WARNING, + "rejected command channel message from %s", + socktext); + isc_socket_detach(&sock); + goto restart; + } + + result = newconnection(listener, sock); + if (result != ISC_R_SUCCESS) { + char socktext[ISC_SOCKADDR_FORMATSIZE]; + isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext)); + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_WARNING, + "dropped command channel from %s: %s", + socktext, isc_result_totext(result)); + isc_socket_detach(&sock); + goto restart; + } + + restart: + control_next(listener); + cleanup: + isc_event_free(&event); +} + +static void +controls_shutdown(ns_controls_t *controls) { + controllistener_t *listener; + controllistener_t *next; + + for (listener = ISC_LIST_HEAD(controls->listeners); + listener != NULL; + listener = next) + { + /* + * This is asynchronous. As listeners shut down, they will + * call their callbacks. + */ + next = ISC_LIST_NEXT(listener, link); + shutdown_listener(listener); + } +} + +void +ns_controls_shutdown(ns_controls_t *controls) { + controls_shutdown(controls); + controls->shuttingdown = true; +} + +static isc_result_t +cfgkeylist_find(const cfg_obj_t *keylist, const char *keyname, + const cfg_obj_t **objp) +{ + const cfg_listelt_t *element; + const char *str; + const cfg_obj_t *obj; + + for (element = cfg_list_first(keylist); + element != NULL; + element = cfg_list_next(element)) + { + obj = cfg_listelt_value(element); + str = cfg_obj_asstring(cfg_map_getname(obj)); + if (strcasecmp(str, keyname) == 0) + break; + } + if (element == NULL) + return (ISC_R_NOTFOUND); + obj = cfg_listelt_value(element); + *objp = obj; + return (ISC_R_SUCCESS); +} + +static isc_result_t +controlkeylist_fromcfg(const cfg_obj_t *keylist, isc_mem_t *mctx, + controlkeylist_t *keyids) +{ + const cfg_listelt_t *element; + char *newstr = NULL; + const char *str; + const cfg_obj_t *obj; + controlkey_t *key; + + for (element = cfg_list_first(keylist); + element != NULL; + element = cfg_list_next(element)) + { + obj = cfg_listelt_value(element); + str = cfg_obj_asstring(obj); + newstr = isc_mem_strdup(mctx, str); + if (newstr == NULL) + goto cleanup; + key = isc_mem_get(mctx, sizeof(*key)); + if (key == NULL) + goto cleanup; + key->keyname = newstr; + key->algorithm = DST_ALG_UNKNOWN; + key->secret.base = NULL; + key->secret.length = 0; + ISC_LINK_INIT(key, link); + ISC_LIST_APPEND(*keyids, key, link); + newstr = NULL; + } + return (ISC_R_SUCCESS); + + cleanup: + if (newstr != NULL) + isc_mem_free(mctx, newstr); + free_controlkeylist(keyids, mctx); + return (ISC_R_NOMEMORY); +} + +static void +register_keys(const cfg_obj_t *control, const cfg_obj_t *keylist, + controlkeylist_t *keyids, isc_mem_t *mctx, const char *socktext) +{ + controlkey_t *keyid, *next; + const cfg_obj_t *keydef; + char secret[1024]; + isc_buffer_t b; + isc_result_t result; + + /* + * Find the keys corresponding to the keyids used by this listener. + */ + for (keyid = ISC_LIST_HEAD(*keyids); keyid != NULL; keyid = next) { + next = ISC_LIST_NEXT(keyid, link); + + result = cfgkeylist_find(keylist, keyid->keyname, &keydef); + if (result != ISC_R_SUCCESS) { + cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING, + "couldn't find key '%s' for use with " + "command channel %s", + keyid->keyname, socktext); + ISC_LIST_UNLINK(*keyids, keyid, link); + free_controlkey(keyid, mctx); + } else { + const cfg_obj_t *algobj = NULL; + const cfg_obj_t *secretobj = NULL; + const char *algstr = NULL; + const char *secretstr = NULL; + unsigned int algtype; + + (void)cfg_map_get(keydef, "algorithm", &algobj); + (void)cfg_map_get(keydef, "secret", &secretobj); + INSIST(algobj != NULL && secretobj != NULL); + + algstr = cfg_obj_asstring(algobj); + secretstr = cfg_obj_asstring(secretobj); + + if (ns_config_getkeyalgorithm2(algstr, NULL, + &algtype, NULL) != ISC_R_SUCCESS) + { + cfg_obj_log(control, ns_g_lctx, + ISC_LOG_WARNING, + "unsupported algorithm '%s' in " + "key '%s' for use with command " + "channel %s", + algstr, keyid->keyname, socktext); + ISC_LIST_UNLINK(*keyids, keyid, link); + free_controlkey(keyid, mctx); + continue; + } + + keyid->algorithm = algtype; + isc_buffer_init(&b, secret, sizeof(secret)); + result = isc_base64_decodestring(secretstr, &b); + + if (result != ISC_R_SUCCESS) { + cfg_obj_log(keydef, ns_g_lctx, ISC_LOG_WARNING, + "secret for key '%s' on " + "command channel %s: %s", + keyid->keyname, socktext, + isc_result_totext(result)); + ISC_LIST_UNLINK(*keyids, keyid, link); + free_controlkey(keyid, mctx); + continue; + } + + keyid->secret.length = isc_buffer_usedlength(&b); + keyid->secret.base = isc_mem_get(mctx, + keyid->secret.length); + if (keyid->secret.base == NULL) { + cfg_obj_log(keydef, ns_g_lctx, ISC_LOG_WARNING, + "couldn't register key '%s': " + "out of memory", keyid->keyname); + ISC_LIST_UNLINK(*keyids, keyid, link); + free_controlkey(keyid, mctx); + break; + } + memmove(keyid->secret.base, isc_buffer_base(&b), + keyid->secret.length); + } + } +} + +#define CHECK(x) \ + do { \ + result = (x); \ + if (result != ISC_R_SUCCESS) \ + goto cleanup; \ + } while (0) + +static isc_result_t +get_rndckey(isc_mem_t *mctx, controlkeylist_t *keyids) { + isc_result_t result; + cfg_parser_t *pctx = NULL; + cfg_obj_t *config = NULL; + const cfg_obj_t *key = NULL; + const cfg_obj_t *algobj = NULL; + const cfg_obj_t *secretobj = NULL; + const char *algstr = NULL; + const char *secretstr = NULL; + controlkey_t *keyid = NULL; + char secret[1024]; + unsigned int algtype; + isc_buffer_t b; + + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_INFO, + "configuring command channel from '%s'", + ns_g_keyfile); + if (! isc_file_exists(ns_g_keyfile)) + return (ISC_R_FILENOTFOUND); + + CHECK(cfg_parser_create(mctx, ns_g_lctx, &pctx)); + CHECK(cfg_parse_file(pctx, ns_g_keyfile, &cfg_type_rndckey, &config)); + CHECK(cfg_map_get(config, "key", &key)); + + keyid = isc_mem_get(mctx, sizeof(*keyid)); + if (keyid == NULL) + CHECK(ISC_R_NOMEMORY); + keyid->keyname = isc_mem_strdup(mctx, + cfg_obj_asstring(cfg_map_getname(key))); + keyid->secret.base = NULL; + keyid->secret.length = 0; + keyid->algorithm = DST_ALG_UNKNOWN; + ISC_LINK_INIT(keyid, link); + if (keyid->keyname == NULL) + CHECK(ISC_R_NOMEMORY); + + CHECK(bind9_check_key(key, ns_g_lctx)); + + (void)cfg_map_get(key, "algorithm", &algobj); + (void)cfg_map_get(key, "secret", &secretobj); + INSIST(algobj != NULL && secretobj != NULL); + + algstr = cfg_obj_asstring(algobj); + secretstr = cfg_obj_asstring(secretobj); + + if (ns_config_getkeyalgorithm2(algstr, NULL, + &algtype, NULL) != ISC_R_SUCCESS) { + cfg_obj_log(key, ns_g_lctx, + ISC_LOG_WARNING, + "unsupported algorithm '%s' in " + "key '%s' for use with command " + "channel", + algstr, keyid->keyname); + goto cleanup; + } + + keyid->algorithm = algtype; + isc_buffer_init(&b, secret, sizeof(secret)); + result = isc_base64_decodestring(secretstr, &b); + + if (result != ISC_R_SUCCESS) { + cfg_obj_log(key, ns_g_lctx, ISC_LOG_WARNING, + "secret for key '%s' on command channel: %s", + keyid->keyname, isc_result_totext(result)); + goto cleanup; + } + + keyid->secret.length = isc_buffer_usedlength(&b); + keyid->secret.base = isc_mem_get(mctx, + keyid->secret.length); + if (keyid->secret.base == NULL) { + cfg_obj_log(key, ns_g_lctx, ISC_LOG_WARNING, + "couldn't register key '%s': " + "out of memory", keyid->keyname); + CHECK(ISC_R_NOMEMORY); + } + memmove(keyid->secret.base, isc_buffer_base(&b), + keyid->secret.length); + ISC_LIST_APPEND(*keyids, keyid, link); + keyid = NULL; + result = ISC_R_SUCCESS; + + cleanup: + if (keyid != NULL) + free_controlkey(keyid, mctx); + if (config != NULL) + cfg_obj_destroy(pctx, &config); + if (pctx != NULL) + cfg_parser_destroy(&pctx); + return (result); +} + +/* + * Ensures that both '*global_keylistp' and '*control_keylistp' are + * valid or both are NULL. + */ +static void +get_key_info(const cfg_obj_t *config, const cfg_obj_t *control, + const cfg_obj_t **global_keylistp, + const cfg_obj_t **control_keylistp) +{ + isc_result_t result; + const cfg_obj_t *control_keylist = NULL; + const cfg_obj_t *global_keylist = NULL; + + REQUIRE(global_keylistp != NULL && *global_keylistp == NULL); + REQUIRE(control_keylistp != NULL && *control_keylistp == NULL); + + control_keylist = cfg_tuple_get(control, "keys"); + + if (!cfg_obj_isvoid(control_keylist) && + cfg_list_first(control_keylist) != NULL) { + result = cfg_map_get(config, "key", &global_keylist); + + if (result == ISC_R_SUCCESS) { + *global_keylistp = global_keylist; + *control_keylistp = control_keylist; + } + } +} + +static void +update_listener(ns_controls_t *cp, controllistener_t **listenerp, + const cfg_obj_t *control, const cfg_obj_t *config, + isc_sockaddr_t *addr, cfg_aclconfctx_t *aclconfctx, + const char *socktext, isc_sockettype_t type) +{ + controllistener_t *listener; + const cfg_obj_t *allow; + const cfg_obj_t *global_keylist = NULL; + const cfg_obj_t *control_keylist = NULL; + dns_acl_t *new_acl = NULL; + controlkeylist_t keys; + isc_result_t result = ISC_R_SUCCESS; + + for (listener = ISC_LIST_HEAD(cp->listeners); + listener != NULL; + listener = ISC_LIST_NEXT(listener, link)) + if (isc_sockaddr_equal(addr, &listener->address)) + break; + + if (listener == NULL) { + *listenerp = NULL; + return; + } + + /* + * There is already a listener for this sockaddr. + * Update the access list and key information. + * + * First try to deal with the key situation. There are a few + * possibilities: + * (a) It had an explicit keylist and still has an explicit keylist. + * (b) It had an automagic key and now has an explicit keylist. + * (c) It had an explicit keylist and now needs an automagic key. + * (d) It has an automagic key and still needs the automagic key. + * + * (c) and (d) are the annoying ones. The caller needs to know + * that it should use the automagic configuration for key information + * in place of the named.conf configuration. + * + * XXXDCL There is one other hazard that has not been dealt with, + * the problem that if a key change is being caused by a control + * channel reload, then the response will be with the new key + * and not able to be decrypted by the client. + */ + if (control != NULL) + get_key_info(config, control, &global_keylist, + &control_keylist); + + if (control_keylist != NULL) { + INSIST(global_keylist != NULL); + + ISC_LIST_INIT(keys); + result = controlkeylist_fromcfg(control_keylist, + listener->mctx, &keys); + if (result == ISC_R_SUCCESS) { + free_controlkeylist(&listener->keys, listener->mctx); + listener->keys = keys; + register_keys(control, global_keylist, &listener->keys, + listener->mctx, socktext); + } + } else { + free_controlkeylist(&listener->keys, listener->mctx); + result = get_rndckey(listener->mctx, &listener->keys); + } + + if (result != ISC_R_SUCCESS && global_keylist != NULL) { + /* + * This message might be a little misleading since the + * "new keys" might in fact be identical to the old ones, + * but tracking whether they are identical just for the + * sake of avoiding this message would be too much trouble. + */ + if (control != NULL) + cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING, + "couldn't install new keys for " + "command channel %s: %s", + socktext, isc_result_totext(result)); + else + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_WARNING, + "couldn't install new keys for " + "command channel %s: %s", + socktext, isc_result_totext(result)); + } + + /* + * Now, keep the old access list unless a new one can be made. + */ + if (control != NULL && type == isc_sockettype_tcp) { + allow = cfg_tuple_get(control, "allow"); + result = cfg_acl_fromconfig(allow, config, ns_g_lctx, + aclconfctx, listener->mctx, 0, + &new_acl); + } else { + result = dns_acl_any(listener->mctx, &new_acl); + } + + if (control != NULL) { + const cfg_obj_t *readonly; + + readonly = cfg_tuple_get(control, "read-only"); + if (!cfg_obj_isvoid(readonly)) + listener->readonly = cfg_obj_asboolean(readonly); + } + + if (result == ISC_R_SUCCESS) { + dns_acl_detach(&listener->acl); + dns_acl_attach(new_acl, &listener->acl); + dns_acl_detach(&new_acl); + /* XXXDCL say the old acl is still used? */ + } else if (control != NULL) + cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING, + "couldn't install new acl for " + "command channel %s: %s", + socktext, isc_result_totext(result)); + else + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_WARNING, + "couldn't install new acl for " + "command channel %s: %s", + socktext, isc_result_totext(result)); + + if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) { + uint32_t perm, owner, group; + perm = cfg_obj_asuint32(cfg_tuple_get(control, "perm")); + owner = cfg_obj_asuint32(cfg_tuple_get(control, "owner")); + group = cfg_obj_asuint32(cfg_tuple_get(control, "group")); + result = ISC_R_SUCCESS; + if (listener->perm != perm || listener->owner != owner || + listener->group != group) + result = isc_socket_permunix(&listener->address, perm, + owner, group); + if (result == ISC_R_SUCCESS) { + listener->perm = perm; + listener->owner = owner; + listener->group = group; + } else if (control != NULL) + cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING, + "couldn't update ownership/permission for " + "command channel %s", socktext); + } + + *listenerp = listener; +} + +static void +add_listener(ns_controls_t *cp, controllistener_t **listenerp, + const cfg_obj_t *control, const cfg_obj_t *config, + isc_sockaddr_t *addr, cfg_aclconfctx_t *aclconfctx, + const char *socktext, isc_sockettype_t type) +{ + isc_mem_t *mctx = cp->server->mctx; + controllistener_t *listener; + const cfg_obj_t *allow; + const cfg_obj_t *global_keylist = NULL; + const cfg_obj_t *control_keylist = NULL; + dns_acl_t *new_acl = NULL; + isc_result_t result = ISC_R_SUCCESS; + + listener = isc_mem_get(mctx, sizeof(*listener)); + if (listener == NULL) + result = ISC_R_NOMEMORY; + + if (result == ISC_R_SUCCESS) { + listener->mctx = NULL; + isc_mem_attach(mctx, &listener->mctx); + listener->controls = cp; + listener->task = cp->server->task; + listener->address = *addr; + listener->sock = NULL; + listener->listening = false; + listener->exiting = false; + listener->acl = NULL; + listener->type = type; + listener->perm = 0; + listener->owner = 0; + listener->group = 0; + listener->readonly = false; + ISC_LINK_INIT(listener, link); + ISC_LIST_INIT(listener->keys); + ISC_LIST_INIT(listener->connections); + + /* + * Make the acl. + */ + if (control != NULL && type == isc_sockettype_tcp) { + allow = cfg_tuple_get(control, "allow"); + result = cfg_acl_fromconfig(allow, config, ns_g_lctx, + aclconfctx, mctx, 0, + &new_acl); + } else { + result = dns_acl_any(mctx, &new_acl); + } + } + + if ((result == ISC_R_SUCCESS) && (control != NULL)) { + const cfg_obj_t *readonly; + + readonly = cfg_tuple_get(control, "read-only"); + if (!cfg_obj_isvoid(readonly)) + listener->readonly = cfg_obj_asboolean(readonly); + } + + if (result == ISC_R_SUCCESS) { + dns_acl_attach(new_acl, &listener->acl); + dns_acl_detach(&new_acl); + + if (config != NULL) + get_key_info(config, control, &global_keylist, + &control_keylist); + + if (control_keylist != NULL) { + result = controlkeylist_fromcfg(control_keylist, + listener->mctx, + &listener->keys); + if (result == ISC_R_SUCCESS) + register_keys(control, global_keylist, + &listener->keys, + listener->mctx, socktext); + } else + result = get_rndckey(mctx, &listener->keys); + + if (result != ISC_R_SUCCESS && control != NULL) + cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING, + "couldn't install keys for " + "command channel %s: %s", + socktext, isc_result_totext(result)); + } + + if (result == ISC_R_SUCCESS) { + int pf = isc_sockaddr_pf(&listener->address); + if ((pf == AF_INET && isc_net_probeipv4() != ISC_R_SUCCESS) || +#ifdef ISC_PLATFORM_HAVESYSUNH + (pf == AF_UNIX && isc_net_probeunix() != ISC_R_SUCCESS) || +#endif + (pf == AF_INET6 && isc_net_probeipv6() != ISC_R_SUCCESS)) + result = ISC_R_FAMILYNOSUPPORT; + } + + if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) + isc_socket_cleanunix(&listener->address, false); + + if (result == ISC_R_SUCCESS) + result = isc_socket_create(ns_g_socketmgr, + isc_sockaddr_pf(&listener->address), + type, &listener->sock); + if (result == ISC_R_SUCCESS) + isc_socket_setname(listener->sock, "control", NULL); + +#ifndef ISC_ALLOW_MAPPED + if (result == ISC_R_SUCCESS) + isc_socket_ipv6only(listener->sock, true); +#endif + + if (result == ISC_R_SUCCESS) + result = isc_socket_bind(listener->sock, &listener->address, + ISC_SOCKET_REUSEADDRESS); + + if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) { + listener->perm = cfg_obj_asuint32(cfg_tuple_get(control, + "perm")); + listener->owner = cfg_obj_asuint32(cfg_tuple_get(control, + "owner")); + listener->group = cfg_obj_asuint32(cfg_tuple_get(control, + "group")); + result = isc_socket_permunix(&listener->address, listener->perm, + listener->owner, listener->group); + } + if (result == ISC_R_SUCCESS) + result = control_listen(listener); + + if (result == ISC_R_SUCCESS) + result = control_accept(listener); + + if (result == ISC_R_SUCCESS) { + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE, + "command channel listening on %s", socktext); + *listenerp = listener; + + } else { + if (listener != NULL) { + listener->exiting = true; + free_listener(listener); + } + + if (control != NULL) + cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING, + "couldn't add command channel %s: %s", + socktext, isc_result_totext(result)); + else + isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE, + "couldn't add command channel %s: %s", + socktext, isc_result_totext(result)); + + *listenerp = NULL; + } + + /* XXXDCL return error results? fail hard? */ +} + +isc_result_t +ns_controls_configure(ns_controls_t *cp, const cfg_obj_t *config, + cfg_aclconfctx_t *aclconfctx) +{ + controllistener_t *listener; + controllistenerlist_t new_listeners; + const cfg_obj_t *controlslist = NULL; + const cfg_listelt_t *element, *element2; + char socktext[ISC_SOCKADDR_FORMATSIZE]; + + ISC_LIST_INIT(new_listeners); + + /* + * Get the list of named.conf 'controls' statements. + */ + (void)cfg_map_get(config, "controls", &controlslist); + + /* + * Run through the new control channel list, noting sockets that + * are already being listened on and moving them to the new list. + * + * Identifying duplicate addr/port combinations is left to either + * the underlying config code, or to the bind attempt getting an + * address-in-use error. + */ + if (controlslist != NULL) { + for (element = cfg_list_first(controlslist); + element != NULL; + element = cfg_list_next(element)) { + const cfg_obj_t *controls; + const cfg_obj_t *inetcontrols = NULL; + + controls = cfg_listelt_value(element); + (void)cfg_map_get(controls, "inet", &inetcontrols); + if (inetcontrols == NULL) + continue; + + for (element2 = cfg_list_first(inetcontrols); + element2 != NULL; + element2 = cfg_list_next(element2)) { + const cfg_obj_t *control; + const cfg_obj_t *obj; + isc_sockaddr_t addr; + + /* + * The parser handles BIND 8 configuration file + * syntax, so it allows unix phrases as well + * inet phrases with no keys{} clause. + */ + control = cfg_listelt_value(element2); + + obj = cfg_tuple_get(control, "address"); + addr = *cfg_obj_assockaddr(obj); + if (isc_sockaddr_getport(&addr) == 0) + isc_sockaddr_setport(&addr, + NS_CONTROL_PORT); + + isc_sockaddr_format(&addr, socktext, + sizeof(socktext)); + + isc_log_write(ns_g_lctx, + NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, + ISC_LOG_DEBUG(9), + "processing control channel %s", + socktext); + + update_listener(cp, &listener, control, config, + &addr, aclconfctx, socktext, + isc_sockettype_tcp); + + if (listener != NULL) + /* + * Remove the listener from the old + * list, so it won't be shut down. + */ + ISC_LIST_UNLINK(cp->listeners, + listener, link); + else + /* + * This is a new listener. + */ + add_listener(cp, &listener, control, + config, &addr, aclconfctx, + socktext, + isc_sockettype_tcp); + + if (listener != NULL) + ISC_LIST_APPEND(new_listeners, + listener, link); + } + } + for (element = cfg_list_first(controlslist); + element != NULL; + element = cfg_list_next(element)) { + const cfg_obj_t *controls; + const cfg_obj_t *unixcontrols = NULL; + + controls = cfg_listelt_value(element); + (void)cfg_map_get(controls, "unix", &unixcontrols); + if (unixcontrols == NULL) + continue; + + for (element2 = cfg_list_first(unixcontrols); + element2 != NULL; + element2 = cfg_list_next(element2)) { + const cfg_obj_t *control; + const cfg_obj_t *path; + isc_sockaddr_t addr; + isc_result_t result; + + /* + * The parser handles BIND 8 configuration file + * syntax, so it allows unix phrases as well + * inet phrases with no keys{} clause. + */ + control = cfg_listelt_value(element2); + + path = cfg_tuple_get(control, "path"); + result = isc_sockaddr_frompath(&addr, + cfg_obj_asstring(path)); + if (result != ISC_R_SUCCESS) { + isc_log_write(ns_g_lctx, + NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, + ISC_LOG_DEBUG(9), + "control channel '%s': %s", + cfg_obj_asstring(path), + isc_result_totext(result)); + continue; + } + + isc_log_write(ns_g_lctx, + NS_LOGCATEGORY_GENERAL, + NS_LOGMODULE_CONTROL, + ISC_LOG_DEBUG(9), + "processing control channel '%s'", + cfg_obj_asstring(path)); + + update_listener(cp, &listener, control, config, + &addr, aclconfctx, + cfg_obj_asstring(path), + isc_sockettype_unix); + + if (listener != NULL) + /* + * Remove the listener from the old + * list, so it won't be shut down. + */ + ISC_LIST_UNLINK(cp->listeners, + listener, link); + else + /* + * This is a new listener. + */ + add_listener(cp, &listener, control, + config, &addr, aclconfctx, + cfg_obj_asstring(path), + isc_sockettype_unix); + + if (listener != NULL) + ISC_LIST_APPEND(new_listeners, + listener, link); + } + } + } else { + int i; + + for (i = 0; i < 2; i++) { + isc_sockaddr_t addr; + + if (i == 0) { + struct in_addr localhost; + + if (isc_net_probeipv4() != ISC_R_SUCCESS) + continue; + localhost.s_addr = htonl(INADDR_LOOPBACK); + isc_sockaddr_fromin(&addr, &localhost, 0); + } else { + if (isc_net_probeipv6() != ISC_R_SUCCESS) + continue; + isc_sockaddr_fromin6(&addr, + &in6addr_loopback, 0); + } + isc_sockaddr_setport(&addr, NS_CONTROL_PORT); + + isc_sockaddr_format(&addr, socktext, sizeof(socktext)); + + update_listener(cp, &listener, NULL, NULL, + &addr, NULL, socktext, + isc_sockettype_tcp); + + if (listener != NULL) + /* + * Remove the listener from the old + * list, so it won't be shut down. + */ + ISC_LIST_UNLINK(cp->listeners, + listener, link); + else + /* + * This is a new listener. + */ + add_listener(cp, &listener, NULL, NULL, + &addr, NULL, socktext, + isc_sockettype_tcp); + + if (listener != NULL) + ISC_LIST_APPEND(new_listeners, + listener, link); + } + } + + /* + * ns_control_shutdown() will stop whatever is on the global + * listeners list, which currently only has whatever sockaddrs + * were in the previous configuration (if any) that do not + * remain in the current configuration. + */ + controls_shutdown(cp); + + /* + * Put all of the valid listeners on the listeners list. + * Anything already on listeners in the process of shutting + * down will be taken care of by listen_done(). + */ + ISC_LIST_APPENDLIST(cp->listeners, new_listeners, link); + return (ISC_R_SUCCESS); +} + +isc_result_t +ns_controls_create(ns_server_t *server, ns_controls_t **ctrlsp) { + isc_mem_t *mctx = server->mctx; + isc_result_t result; + ns_controls_t *controls = isc_mem_get(mctx, sizeof(*controls)); + + if (controls == NULL) + return (ISC_R_NOMEMORY); + controls->server = server; + ISC_LIST_INIT(controls->listeners); + controls->shuttingdown = false; + controls->symtab = NULL; + result = isccc_cc_createsymtab(&controls->symtab); + if (result != ISC_R_SUCCESS) { + isc_mem_put(server->mctx, controls, sizeof(*controls)); + return (result); + } + *ctrlsp = controls; + return (ISC_R_SUCCESS); +} + +void +ns_controls_destroy(ns_controls_t **ctrlsp) { + ns_controls_t *controls = *ctrlsp; + + REQUIRE(ISC_LIST_EMPTY(controls->listeners)); + + isccc_symtab_destroy(&controls->symtab); + isc_mem_put(controls->server->mctx, controls, sizeof(*controls)); + *ctrlsp = NULL; +} |