diff options
author | Nick Mathewson <nickm@torproject.org> | 2011-12-07 21:12:20 -0500 |
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committer | Nick Mathewson <nickm@torproject.org> | 2011-12-07 21:12:20 -0500 |
commit | 8bb853b2a23e56505d598ee9c38ce56b4afe248c (patch) | |
tree | 929849a8ce86601cc4efe7e129472b99aedc0f7d /src | |
parent | 299034edf5e05c81d535fc7d0b2120b6a2810477 (diff) | |
parent | 0ebcf345ce6087deeb9f1a1a54b9e6d003822fc3 (diff) | |
download | tor-8bb853b2a23e56505d598ee9c38ce56b4afe248c.tar.gz tor-8bb853b2a23e56505d598ee9c38ce56b4afe248c.zip |
Merge remote-tracking branch 'public/revert_4312'
Diffstat (limited to 'src')
-rw-r--r-- | src/common/compat_libevent.c | 59 | ||||
-rw-r--r-- | src/common/compat_libevent.h | 6 | ||||
-rw-r--r-- | src/common/tortls.c | 177 | ||||
-rw-r--r-- | src/common/tortls.h | 5 | ||||
-rw-r--r-- | src/common/util.c | 4 | ||||
-rw-r--r-- | src/or/connection_or.c | 51 | ||||
-rw-r--r-- | src/or/or.h | 2 |
7 files changed, 102 insertions, 202 deletions
diff --git a/src/common/compat_libevent.c b/src/common/compat_libevent.c index 67f465927c..7a28c9bc9b 100644 --- a/src/common/compat_libevent.c +++ b/src/common/compat_libevent.c @@ -243,8 +243,8 @@ tor_libevent_initialize(tor_libevent_cfg *torcfg) * again. */ #if defined(MS_WINDOWS) && defined(USE_BUFFEREVENTS) if (torcfg->disable_iocp == 0) { - log_warn(LD_GENERAL, "Unable to initialize Libevent. Trying again " - "with IOCP disabled."); + log_warn(LD_GENERAL, "Unable to initialize Libevent. Trying again with " + "IOCP disabled."); } else #endif { @@ -254,6 +254,7 @@ tor_libevent_initialize(tor_libevent_cfg *torcfg) torcfg->disable_iocp = 1; goto retry; } + } #else the_event_base = event_init(); @@ -558,60 +559,6 @@ tor_check_libevent_header_compatibility(void) #endif } -struct tor_libevent_action_t { - struct event *ev; - void (*cb)(void *arg); - void *arg; -}; - -/** Callback for tor_run_in_libevent_loop */ -static void -run_runnable_cb(evutil_socket_t s, short what, void *arg) -{ - tor_libevent_action_t *r = arg; - void (*cb)(void *) = r->cb; - void *cb_arg = r->arg; - (void)what; - (void)s; - tor_event_free(r->ev); - tor_free(r); - - cb(cb_arg); -} - -/** Cause cb(arg) to run later on this iteration of the libevent loop, or in - * the next iteration of the libevent loop. This is useful for when you're - * deep inside a no-reentrant code and there's some function you want to call - * without worrying about whether it might cause reeentrant invocation. - */ -tor_libevent_action_t * -tor_run_in_libevent_loop(void (*cb)(void *arg), void *arg) -{ - tor_libevent_action_t *r = tor_malloc(sizeof(tor_libevent_action_t)); - r->cb = cb; - r->arg = arg; - r->ev = tor_event_new(tor_libevent_get_base(), -1, EV_TIMEOUT, - run_runnable_cb, r); - if (!r->ev) { - tor_free(r); - return NULL; - } - /* Make the event active immediately. */ - event_active(r->ev, EV_TIMEOUT, 1); - - return r; -} - -/** - * Cancel <b>action</b> without running it. - */ -void -tor_cancel_libevent_action(tor_libevent_action_t *action) -{ - tor_event_free(action->ev); - tor_free(action); -} - /* If possible, we're going to try to use Libevent's periodic timer support, since it does a pretty good job of making sure that periodic events get diff --git a/src/common/compat_libevent.h b/src/common/compat_libevent.h index 4076cc0e08..0247297177 100644 --- a/src/common/compat_libevent.h +++ b/src/common/compat_libevent.h @@ -44,12 +44,8 @@ void tor_event_free(struct event *ev); #define tor_evdns_add_server_port evdns_add_server_port #endif -typedef struct tor_libevent_action_t tor_libevent_action_t; -tor_libevent_action_t *tor_run_in_libevent_loop(void (*cb)(void *arg), - void *arg); -void tor_cancel_libevent_action(tor_libevent_action_t *action); - typedef struct periodic_timer_t periodic_timer_t; + periodic_timer_t *periodic_timer_new(struct event_base *base, const struct timeval *tv, void (*cb)(periodic_timer_t *timer, void *data), diff --git a/src/common/tortls.c b/src/common/tortls.c index 18f2684707..e4992efc6d 100644 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@ -52,6 +52,7 @@ #include <event2/bufferevent_ssl.h> #include <event2/buffer.h> #include <event2/event.h> +#include "compat_libevent.h" #endif #define CRYPTO_PRIVATE /* to import prototypes from crypto.h */ @@ -63,7 +64,6 @@ #include "torlog.h" #include "container.h" #include <string.h> -#include "compat_libevent.h" /* Enable the "v2" TLS handshake. */ @@ -146,7 +146,7 @@ struct tor_tls_t { /** True iff we should call negotiated_callback when we're done reading. */ unsigned int got_renegotiate:1; /** Incremented every time we start the server side of a handshake. */ - unsigned int server_handshake_count:2; + uint8_t server_handshake_count; size_t wantwrite_n; /**< 0 normally, >0 if we returned wantwrite last * time. */ /** Last values retrieved from BIO_number_read()/write(); see @@ -157,11 +157,6 @@ struct tor_tls_t { /** If set, a callback to invoke whenever the client tries to renegotiate * the handshake. */ void (*negotiated_callback)(tor_tls_t *tls, void *arg); - - /** Callback to invoke whenever a client tries to renegotiate more - than once. */ - void (*excess_renegotiations_callback)(void *); - /** Argument to pass to negotiated_callback. */ void *callback_arg; }; @@ -585,8 +580,6 @@ tor_tls_create_certificate(crypto_pk_env_t *rsa, const char *cname_sign, unsigned int cert_lifetime) { - /* OpenSSL generates self-signed certificates with random 64-bit serial - * numbers, so let's do that too. */ #define SERIAL_NUMBER_SIZE 8 time_t start_time, end_time; @@ -614,12 +607,12 @@ tor_tls_create_certificate(crypto_pk_env_t *rsa, goto error; { /* our serial number is 8 random bytes. */ - if (crypto_rand((char *)serial_tmp, sizeof(serial_tmp)) < 0) - goto error; - if (!(serial_number = BN_bin2bn(serial_tmp, sizeof(serial_tmp), NULL))) - goto error; - if (!(BN_to_ASN1_INTEGER(serial_number, X509_get_serialNumber(x509)))) - goto error; + if (crypto_rand((char *)serial_tmp, sizeof(serial_tmp)) < 0) + goto error; + if (!(serial_number = BN_bin2bn(serial_tmp, sizeof(serial_tmp), NULL))) + goto error; + if (!(BN_to_ASN1_INTEGER(serial_number, X509_get_serialNumber(x509)))) + goto error; } if (!(name = tor_x509_name_new(cname))) @@ -1319,42 +1312,55 @@ tor_tls_client_is_using_v2_ciphers(const SSL *ssl, const char *address) return 1; } -/** We got an SSL ClientHello message. This might mean that the - * client wants to initiate a renegotiation and appropriate actions - * must be taken. */ static void -tor_tls_got_client_hello(tor_tls_t *tls) +tor_tls_debug_state_callback(const SSL *ssl, int type, int val) { - if (tls->server_handshake_count < 3) - ++tls->server_handshake_count; + log_debug(LD_HANDSHAKE, "SSL %p is now in state %s [type=%d,val=%d].", + ssl, ssl_state_to_string(ssl->state), type, val); +} - if (tls->server_handshake_count == 2) { - if (!tls->negotiated_callback) { - log_warn(LD_BUG, "Got a renegotiation request but we don't" - " have a renegotiation callback set!"); - } +/** Invoked when we're accepting a connection on <b>ssl</b>, and the connection + * changes state. We use this: + * <ul><li>To alter the state of the handshake partway through, so we + * do not send or request extra certificates in v2 handshakes.</li> + * <li>To detect renegotiation</li></ul> + */ +static void +tor_tls_server_info_callback(const SSL *ssl, int type, int val) +{ + tor_tls_t *tls; + (void) val; - tls->got_renegotiate = 1; - } else if (tls->server_handshake_count > 2 && - tls->excess_renegotiations_callback) { - /* We got more than one renegotiation requests. The Tor protocol - needs just one renegotiation; more than that probably means - They are trying to DoS us and we have to stop them. */ + tor_tls_debug_state_callback(ssl, type, val); - tls->excess_renegotiations_callback(tls->callback_arg); + if (type != SSL_CB_ACCEPT_LOOP) + return; + if (ssl->state != SSL3_ST_SW_SRVR_HELLO_A) + return; + + tls = tor_tls_get_by_ssl(ssl); + if (tls) { + /* Check whether we're watching for renegotiates. If so, this is one! */ + if (tls->negotiated_callback) + tls->got_renegotiate = 1; + if (tls->server_handshake_count < 127) /*avoid any overflow possibility*/ + ++tls->server_handshake_count; + } else { + log_warn(LD_BUG, "Couldn't look up the tls for an SSL*. How odd!"); + return; } /* Now check the cipher list. */ - if (tor_tls_client_is_using_v2_ciphers(tls->ssl, ADDR(tls))) { + if (tor_tls_client_is_using_v2_ciphers(ssl, ADDR(tls))) { /*XXXX_TLS keep this from happening more than once! */ /* Yes, we're casting away the const from ssl. This is very naughty of us. * Let's hope openssl doesn't notice! */ /* Set SSL_MODE_NO_AUTO_CHAIN to keep from sending back any extra certs. */ - SSL_set_mode((SSL*) tls->ssl, SSL_MODE_NO_AUTO_CHAIN); + SSL_set_mode((SSL*) ssl, SSL_MODE_NO_AUTO_CHAIN); /* Don't send a hello request. */ - SSL_set_verify((SSL*) tls->ssl, SSL_VERIFY_NONE, NULL); + SSL_set_verify((SSL*) ssl, SSL_VERIFY_NONE, NULL); if (tls) { tls->wasV2Handshake = 1; @@ -1369,34 +1375,6 @@ tor_tls_got_client_hello(tor_tls_t *tls) } #endif -/** This is a callback function for SSL_set_info_callback() and it - * will be called in every SSL state change. - * It logs the SSL state change, and executes any actions that must be - * taken. */ -static void -tor_tls_state_changed_callback(const SSL *ssl, int type, int val) -{ - log_debug(LD_HANDSHAKE, "SSL %p is now in state %s [type=%d,val=%d].", - ssl, ssl_state_to_string(ssl->state), type, val); - -#ifdef V2_HANDSHAKE_SERVER - if (type == SSL_CB_ACCEPT_LOOP && - ssl->state == SSL3_ST_SW_SRVR_HELLO_A) { - - /* Call tor_tls_got_client_hello() for every SSL ClientHello we - receive. */ - - tor_tls_t *tls = tor_tls_get_by_ssl(ssl); - if (!tls) { - log_warn(LD_BUG, "Couldn't look up the tls for an SSL*. How odd!"); - return; - } - - tor_tls_got_client_hello(tls); - } -#endif -} - /** Replace *<b>ciphers</b> with a new list of SSL ciphersuites: specifically, * a list designed to mimic a common web browser. Some of the ciphers in the * list won't actually be implemented by OpenSSL: that's okay so long as the @@ -1538,8 +1516,14 @@ tor_tls_new(int sock, int isServer) log_warn(LD_NET, "Newly created BIO has read count %lu, write count %lu", result->last_read_count, result->last_write_count); } - - SSL_set_info_callback(result->ssl, tor_tls_state_changed_callback); +#ifdef V2_HANDSHAKE_SERVER + if (isServer) { + SSL_set_info_callback(result->ssl, tor_tls_server_info_callback); + } else +#endif + { + SSL_set_info_callback(result->ssl, tor_tls_debug_state_callback); + } /* Not expected to get called. */ tls_log_errors(NULL, LOG_WARN, LD_NET, "creating tor_tls_t object"); @@ -1557,22 +1541,25 @@ tor_tls_set_logged_address(tor_tls_t *tls, const char *address) tls->address = tor_strdup(address); } -/** Set <b>cb</b> to be called with argument <b>arg</b> whenever - * <b>tls</b> next gets a client-side renegotiate in the middle of a - * read. Set <b>cb2</b> to be called with argument <b>arg</b> whenever - * <b>tls</b> gets excess renegotiation requests. Do not invoke this - * function until <em>after</em> initial handshaking is done! +/** Set <b>cb</b> to be called with argument <b>arg</b> whenever <b>tls</b> + * next gets a client-side renegotiate in the middle of a read. Do not + * invoke this function until <em>after</em> initial handshaking is done! */ void -tor_tls_set_renegotiate_callbacks(tor_tls_t *tls, +tor_tls_set_renegotiate_callback(tor_tls_t *tls, void (*cb)(tor_tls_t *, void *arg), - void (*cb2)(void *), void *arg) { tls->negotiated_callback = cb; - tls->excess_renegotiations_callback = cb2; tls->callback_arg = arg; tls->got_renegotiate = 0; +#ifdef V2_HANDSHAKE_SERVER + if (cb) { + SSL_set_info_callback(tls->ssl, tor_tls_server_info_callback); + } else { + SSL_set_info_callback(tls->ssl, tor_tls_debug_state_callback); + } +#endif } /** If this version of openssl requires it, turn on renegotiation on @@ -1592,6 +1579,16 @@ tor_tls_unblock_renegotiation(tor_tls_t *tls) } } +/** If this version of openssl supports it, turn off renegotiation on + * <b>tls</b>. (Our protocol never requires this for security, but it's nice + * to use belt-and-suspenders here.) + */ +void +tor_tls_block_renegotiation(tor_tls_t *tls) +{ + tls->ssl->s3->flags &= ~SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION; +} + void tor_tls_assert_renegotiation_unblocked(tor_tls_t *tls) { @@ -1629,7 +1626,6 @@ tor_tls_free(tor_tls_t *tls) SSL_free(tls->ssl); tls->ssl = NULL; tls->negotiated_callback = NULL; - tls->excess_renegotiations_callback = NULL; if (tls->context) tor_tls_context_decref(tls->context); tor_free(tls->address); @@ -1651,30 +1647,19 @@ tor_tls_read(tor_tls_t *tls, char *cp, size_t len) tor_assert(tls->state == TOR_TLS_ST_OPEN); tor_assert(len<INT_MAX); r = SSL_read(tls->ssl, cp, (int)len); - if (r > 0) /* return the number of characters read */ - return r; - - /* If we got here, SSL_read() did not go as expected. */ - - err = tor_tls_get_error(tls, r, CATCH_ZERO, "reading", LOG_DEBUG, LD_NET); - + if (r > 0) { #ifdef V2_HANDSHAKE_SERVER - if (tls->got_renegotiate) { - if (tls->server_handshake_count != 2) { - log_warn(LD_BUG, "We did not notice renegotiation in a timely " - "fashion (%u)!", tls->server_handshake_count); + if (tls->got_renegotiate) { + /* Renegotiation happened! */ + log_info(LD_NET, "Got a TLS renegotiation from %s", ADDR(tls)); + if (tls->negotiated_callback) + tls->negotiated_callback(tls, tls->callback_arg); + tls->got_renegotiate = 0; } - - /* Renegotiation happened! */ - log_info(LD_NET, "Got a TLS renegotiation from %s", ADDR(tls)); - if (tls->negotiated_callback) - tls->negotiated_callback(tls, tls->callback_arg); - tls->got_renegotiate = 0; - +#endif return r; } -#endif - + err = tor_tls_get_error(tls, r, CATCH_ZERO, "reading", LOG_DEBUG, LD_NET); if (err == _TOR_TLS_ZERORETURN || err == TOR_TLS_CLOSE) { log_debug(LD_NET,"read returned r=%d; TLS is closed",r); tls->state = TOR_TLS_ST_CLOSED; @@ -1711,7 +1696,6 @@ tor_tls_write(tor_tls_t *tls, const char *cp, size_t n) } r = SSL_write(tls->ssl, cp, (int)n); err = tor_tls_get_error(tls, r, 0, "writing", LOG_INFO, LD_NET); - if (err == TOR_TLS_DONE) { return r; } @@ -1776,6 +1760,7 @@ tor_tls_finish_handshake(tor_tls_t *tls) { int r = TOR_TLS_DONE; if (tls->isServer) { + SSL_set_info_callback(tls->ssl, NULL); SSL_set_verify(tls->ssl, SSL_VERIFY_PEER, always_accept_verify_cb); /* There doesn't seem to be a clear OpenSSL API to clear mode flags. */ tls->ssl->mode &= ~SSL_MODE_NO_AUTO_CHAIN; diff --git a/src/common/tortls.h b/src/common/tortls.h index 9f86e37127..673f18dfe8 100644 --- a/src/common/tortls.h +++ b/src/common/tortls.h @@ -13,7 +13,6 @@ #include "crypto.h" #include "compat.h" -#include "compat_libevent.h" /* Opaque structure to hold a TLS connection. */ typedef struct tor_tls_t tor_tls_t; @@ -61,9 +60,8 @@ int tor_tls_context_init(int is_public_server, unsigned int key_lifetime); tor_tls_t *tor_tls_new(int sock, int is_server); void tor_tls_set_logged_address(tor_tls_t *tls, const char *address); -void tor_tls_set_renegotiate_callbacks(tor_tls_t *tls, +void tor_tls_set_renegotiate_callback(tor_tls_t *tls, void (*cb)(tor_tls_t *, void *arg), - void (*cb2)(void *), void *arg); int tor_tls_is_server(tor_tls_t *tls); void tor_tls_free(tor_tls_t *tls); @@ -79,6 +77,7 @@ int tor_tls_handshake(tor_tls_t *tls); int tor_tls_finish_handshake(tor_tls_t *tls); int tor_tls_renegotiate(tor_tls_t *tls); void tor_tls_unblock_renegotiation(tor_tls_t *tls); +void tor_tls_block_renegotiation(tor_tls_t *tls); void tor_tls_assert_renegotiation_unblocked(tor_tls_t *tls); int tor_tls_shutdown(tor_tls_t *tls); int tor_tls_get_pending_bytes(tor_tls_t *tls); diff --git a/src/common/util.c b/src/common/util.c index 6d488d9963..a59cab0bbe 100644 --- a/src/common/util.c +++ b/src/common/util.c @@ -3661,8 +3661,8 @@ tor_get_exit_code(const process_handle_t *process_handle, /* Process has not exited */ return PROCESS_EXIT_RUNNING; } else if (retval != process_handle->pid) { - log_warn(LD_GENERAL, "waitpid() failed for PID %d: %s", - process_handle->pid, strerror(errno)); + log_warn(LD_GENERAL, "waitpid() failed for PID %d: %s", process_handle->pid, + strerror(errno)); return PROCESS_EXIT_ERROR; } diff --git a/src/or/connection_or.c b/src/or/connection_or.c index b865e13664..cbe678d6cf 100644 --- a/src/or/connection_or.c +++ b/src/or/connection_or.c @@ -42,7 +42,6 @@ static int connection_or_check_valid_tls_handshake(or_connection_t *conn, char *digest_rcvd_out); static void connection_or_tls_renegotiated_cb(tor_tls_t *tls, void *_conn); -static void connection_or_close_connection_cb(void *_conn); #ifdef USE_BUFFEREVENTS static void connection_or_handle_event_cb(struct bufferevent *bufev, @@ -493,9 +492,6 @@ connection_or_about_to_close(or_connection_t *or_conn) time_t now = time(NULL); connection_t *conn = TO_CONN(or_conn); - if (or_conn->pending_action) - tor_cancel_libevent_action(or_conn->pending_action); - /* Remember why we're closing this connection. */ if (conn->state != OR_CONN_STATE_OPEN) { /* Inform any pending (not attached) circs that they should @@ -1103,16 +1099,12 @@ connection_tls_start_handshake(or_connection_t *conn, int receiving) conn->_base.state = OR_CONN_STATE_TLS_HANDSHAKING; tor_assert(!conn->tls); conn->tls = tor_tls_new(conn->_base.s, receiving); + tor_tls_set_logged_address(conn->tls, // XXX client and relay? + escaped_safe_str(conn->_base.address)); if (!conn->tls) { log_warn(LD_BUG,"tor_tls_new failed. Closing."); return -1; } - tor_tls_set_logged_address(conn->tls, // XXX client and relay? - escaped_safe_str(conn->_base.address)); - tor_tls_set_renegotiate_callbacks(conn->tls, - connection_or_tls_renegotiated_cb, - connection_or_close_connection_cb, - conn); #ifdef USE_BUFFEREVENTS if (connection_type_uses_bufferevent(TO_CONN(conn))) { const int filtering = get_options()->_UseFilteringSSLBufferevents; @@ -1157,6 +1149,10 @@ connection_or_tls_renegotiated_cb(tor_tls_t *tls, void *_conn) or_connection_t *conn = _conn; (void)tls; + /* Don't invoke this again. */ + tor_tls_set_renegotiate_callback(tls, NULL, NULL); + tor_tls_block_renegotiation(tls); + if (connection_tls_finish_handshake(conn) < 0) { /* XXXX_TLS double-check that it's ok to do this from inside read. */ /* XXXX_TLS double-check that this verifies certificates. */ @@ -1164,34 +1160,6 @@ connection_or_tls_renegotiated_cb(tor_tls_t *tls, void *_conn) } } -/*DOCDOC*/ -static void -close_connection_libevent_cb(void *_conn) -{ - or_connection_t *or_conn = _conn; - connection_t *conn = TO_CONN(or_conn); - - or_conn->pending_action = NULL; - - connection_stop_reading(conn); - if (!conn->marked_for_close) - connection_mark_for_close(conn); -} - -/* DOCDOC */ -static void -connection_or_close_connection_cb(void *_conn) -{ - /* We can't close their connection from in here since it's an OpenSSL - callback, so we set a libevent event that triggers in the next event - loop and closes the connection. */ - or_connection_t *or_conn = _conn; - if (or_conn->_base.marked_for_close || or_conn->pending_action) - return; - or_conn->pending_action = - tor_run_in_libevent_loop(close_connection_libevent_cb, or_conn); -} - /** Move forward with the tls handshake. If it finishes, hand * <b>conn</b> to connection_tls_finish_handshake(). * @@ -1238,6 +1206,9 @@ connection_tls_continue_handshake(or_connection_t *conn) /* v2/v3 handshake, but not a client. */ log_debug(LD_OR, "Done with initial SSL handshake (server-side). " "Expecting renegotiation or VERSIONS cell"); + tor_tls_set_renegotiate_callback(conn->tls, + connection_or_tls_renegotiated_cb, + conn); conn->_base.state = OR_CONN_STATE_TLS_SERVER_RENEGOTIATING; connection_stop_writing(TO_CONN(conn)); connection_start_reading(TO_CONN(conn)); @@ -1298,6 +1269,9 @@ connection_or_handle_event_cb(struct bufferevent *bufev, short event, } else if (tor_tls_get_num_server_handshakes(conn->tls) == 1) { /* v2 or v3 handshake, as a server. Only got one handshake, so * wait for the next one. */ + tor_tls_set_renegotiate_callback(conn->tls, + connection_or_tls_renegotiated_cb, + conn); conn->_base.state = OR_CONN_STATE_TLS_SERVER_RENEGOTIATING; /* return 0; */ return; /* ???? */ @@ -1567,6 +1541,7 @@ connection_tls_finish_handshake(or_connection_t *conn) connection_or_init_conn_from_address(conn, &conn->_base.addr, conn->_base.port, digest_rcvd, 0); } + tor_tls_block_renegotiation(conn->tls); return connection_or_set_state_open(conn); } else { conn->_base.state = OR_CONN_STATE_OR_HANDSHAKING_V2; diff --git a/src/or/or.h b/src/or/or.h index eb9f060e50..6ff02ee36c 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -1276,8 +1276,6 @@ typedef struct or_connection_t { unsigned active_circuit_pqueue_last_recalibrated; struct or_connection_t *next_with_same_id; /**< Next connection with same * identity digest as this one. */ - - tor_libevent_action_t *pending_action; } or_connection_t; /** Subtype of connection_t for an "edge connection" -- that is, an entry (ap) |