commit a634f6b64c485dc2e4ff326e46340dbff2ad49d5 Author: David Goulet dgoulet@torproject.org Date: Wed Jan 27 10:19:51 2021 -0500

dos: Move config options within the subsystem

Closes #40261

Signed-off-by: David Goulet dgoulet@torproject.org --- changes/ticket40261 | 4 ++++ src/app/config/config.c | 13 ------------ src/app/config/or_options_st.h | 29 -------------------------- src/core/or/dos.c | 42 +++++++++++++++++++------------------ src/core/or/dos_config.c | 29 ++++++++++++++++++++++++++ src/core/or/dos_config.h | 16 ++++++++++++++ src/core/or/dos_options.inc | 47 ++++++++++++++++++++++++++++++++++++++++++ src/core/or/dos_options_st.h | 20 ++++++++++++++++++ src/core/or/dos_sys.c | 28 ++++++++++++++++++++++++- src/core/or/dos_sys.h | 3 +++ src/core/or/include.am | 4 ++++ 11 files changed, 172 insertions(+), 63 deletions(-)

diff --git a/changes/ticket40261 b/changes/ticket40261 new file mode 100644 index 0000000000..f8d05a25be --- /dev/null +++ b/changes/ticket40261 @@ -0,0 +1,4 @@ + o Code simplification and refactoring (metrics, DoS): + - Move the DoS subsystem into the subsys manager including its configuration + options. Closes ticket 40261. + diff --git a/src/app/config/config.c b/src/app/config/config.c index 2d4155e9bc..9f366f9ee4 100644 --- a/src/app/config/config.c +++ b/src/app/config/config.c @@ -428,19 +428,6 @@ static const config_var_t option_vars_[] = { V(DormantTimeoutDisabledByIdleStreams, BOOL, "1"), V(DormantOnFirstStartup, BOOL, "0"), V(DormantCanceledByStartup, BOOL, "0"), - /* DoS circuit creation options. */ - V(DoSCircuitCreationEnabled, AUTOBOOL, "auto"), - V(DoSCircuitCreationMinConnections, POSINT, "0"), - V(DoSCircuitCreationRate, POSINT, "0"), - V(DoSCircuitCreationBurst, POSINT, "0"), - V(DoSCircuitCreationDefenseType, INT, "0"), - V(DoSCircuitCreationDefenseTimePeriod, INTERVAL, "0"), - /* DoS connection options. */ - V(DoSConnectionEnabled, AUTOBOOL, "auto"), - V(DoSConnectionMaxConcurrentCount, POSINT, "0"), - V(DoSConnectionDefenseType, INT, "0"), - /* DoS single hop client options. */ - V(DoSRefuseSingleHopClientRendezvous, AUTOBOOL, "auto"), V(DownloadExtraInfo, BOOL, "0"), V(TestingEnableConnBwEvent, BOOL, "0"), V(TestingEnableCellStatsEvent, BOOL, "0"), diff --git a/src/app/config/or_options_st.h b/src/app/config/or_options_st.h index 4364f145ed..714034b28d 100644 --- a/src/app/config/or_options_st.h +++ b/src/app/config/or_options_st.h @@ -1031,35 +1031,6 @@ struct or_options_t { */ int DisableSignalHandlers;

- /** Autobool: Is the circuit creation DoS mitigation subsystem enabled? */ - int DoSCircuitCreationEnabled; - /** Minimum concurrent connection needed from one single address before any - * defense is used. */ - int DoSCircuitCreationMinConnections; - /** Circuit rate used to refill the token bucket. */ - int DoSCircuitCreationRate; - /** Maximum allowed burst of circuits. Reaching that value, the address is - * detected as malicious and a defense might be used. */ - int DoSCircuitCreationBurst; - /** When an address is marked as malicious, what defense should be used - * against it. See the dos_cc_defense_type_t enum. */ - int DoSCircuitCreationDefenseType; - /** For how much time (in seconds) the defense is applicable for a malicious - * address. A random time delta is added to the defense time of an address - * which will be between 1 second and half of this value. */ - int DoSCircuitCreationDefenseTimePeriod; - - /** Autobool: Is the DoS connection mitigation subsystem enabled? */ - int DoSConnectionEnabled; - /** Maximum concurrent connection allowed per address. */ - int DoSConnectionMaxConcurrentCount; - /** When an address is reaches the maximum count, what defense should be - * used against it. See the dos_conn_defense_type_t enum. */ - int DoSConnectionDefenseType; - - /** Autobool: Do we refuse single hop client rendezvous? */ - int DoSRefuseSingleHopClientRendezvous; - /** Interval: how long without activity does it take for a client * to become dormant? **/ diff --git a/src/core/or/dos.c b/src/core/or/dos.c index 41bf303ffe..a761082be0 100644 --- a/src/core/or/dos.c +++ b/src/core/or/dos.c @@ -23,7 +23,9 @@ #include "lib/crypt_ops/crypto_rand.h"

#include "core/or/dos.h" +#include "core/or/dos_sys.h"

+#include "core/or/dos_options_st.h" #include "core/or/or_connection_st.h"

/* @@ -77,8 +79,8 @@ static uint64_t num_single_hop_client_refused; MOCK_IMPL(STATIC unsigned int, get_param_cc_enabled, (const networkstatus_t *ns)) { - if (get_options()->DoSCircuitCreationEnabled != -1) { - return get_options()->DoSCircuitCreationEnabled; + if (dos_get_options()->DoSCircuitCreationEnabled != -1) { + return dos_get_options()->DoSCircuitCreationEnabled; }

return !!networkstatus_get_param(ns, "DoSCircuitCreationEnabled", @@ -90,8 +92,8 @@ get_param_cc_enabled, (const networkstatus_t *ns)) STATIC uint32_t get_param_cc_min_concurrent_connection(const networkstatus_t *ns) { - if (get_options()->DoSCircuitCreationMinConnections) { - return get_options()->DoSCircuitCreationMinConnections; + if (dos_get_options()->DoSCircuitCreationMinConnections) { + return dos_get_options()->DoSCircuitCreationMinConnections; } return networkstatus_get_param(ns, "DoSCircuitCreationMinConnections", DOS_CC_MIN_CONCURRENT_CONN_DEFAULT, @@ -104,8 +106,8 @@ static uint32_t get_param_cc_circuit_rate(const networkstatus_t *ns) { /* This is in seconds. */ - if (get_options()->DoSCircuitCreationRate) { - return get_options()->DoSCircuitCreationRate; + if (dos_get_options()->DoSCircuitCreationRate) { + return dos_get_options()->DoSCircuitCreationRate; } return networkstatus_get_param(ns, "DoSCircuitCreationRate", DOS_CC_CIRCUIT_RATE_DEFAULT, @@ -117,8 +119,8 @@ get_param_cc_circuit_rate(const networkstatus_t *ns) STATIC uint32_t get_param_cc_circuit_burst(const networkstatus_t *ns) { - if (get_options()->DoSCircuitCreationBurst) { - return get_options()->DoSCircuitCreationBurst; + if (dos_get_options()->DoSCircuitCreationBurst) { + return dos_get_options()->DoSCircuitCreationBurst; } return networkstatus_get_param(ns, "DoSCircuitCreationBurst", DOS_CC_CIRCUIT_BURST_DEFAULT, @@ -129,8 +131,8 @@ get_param_cc_circuit_burst(const networkstatus_t *ns) static uint32_t get_param_cc_defense_type(const networkstatus_t *ns) { - if (get_options()->DoSCircuitCreationDefenseType) { - return get_options()->DoSCircuitCreationDefenseType; + if (dos_get_options()->DoSCircuitCreationDefenseType) { + return dos_get_options()->DoSCircuitCreationDefenseType; } return networkstatus_get_param(ns, "DoSCircuitCreationDefenseType", DOS_CC_DEFENSE_TYPE_DEFAULT, @@ -143,8 +145,8 @@ static int32_t get_param_cc_defense_time_period(const networkstatus_t *ns) { /* Time in seconds. */ - if (get_options()->DoSCircuitCreationDefenseTimePeriod) { - return get_options()->DoSCircuitCreationDefenseTimePeriod; + if (dos_get_options()->DoSCircuitCreationDefenseTimePeriod) { + return dos_get_options()->DoSCircuitCreationDefenseTimePeriod; } return networkstatus_get_param(ns, "DoSCircuitCreationDefenseTimePeriod", DOS_CC_DEFENSE_TIME_PERIOD_DEFAULT, @@ -156,8 +158,8 @@ get_param_cc_defense_time_period(const networkstatus_t *ns) MOCK_IMPL(STATIC unsigned int, get_param_conn_enabled, (const networkstatus_t *ns)) { - if (get_options()->DoSConnectionEnabled != -1) { - return get_options()->DoSConnectionEnabled; + if (dos_get_options()->DoSConnectionEnabled != -1) { + return dos_get_options()->DoSConnectionEnabled; } return !!networkstatus_get_param(ns, "DoSConnectionEnabled", DOS_CONN_ENABLED_DEFAULT, 0, 1); @@ -168,8 +170,8 @@ get_param_conn_enabled, (const networkstatus_t *ns)) STATIC uint32_t get_param_conn_max_concurrent_count(const networkstatus_t *ns) { - if (get_options()->DoSConnectionMaxConcurrentCount) { - return get_options()->DoSConnectionMaxConcurrentCount; + if (dos_get_options()->DoSConnectionMaxConcurrentCount) { + return dos_get_options()->DoSConnectionMaxConcurrentCount; } return networkstatus_get_param(ns, "DoSConnectionMaxConcurrentCount", DOS_CONN_MAX_CONCURRENT_COUNT_DEFAULT, @@ -180,8 +182,8 @@ get_param_conn_max_concurrent_count(const networkstatus_t *ns) static uint32_t get_param_conn_defense_type(const networkstatus_t *ns) { - if (get_options()->DoSConnectionDefenseType) { - return get_options()->DoSConnectionDefenseType; + if (dos_get_options()->DoSConnectionDefenseType) { + return dos_get_options()->DoSConnectionDefenseType; } return networkstatus_get_param(ns, "DoSConnectionDefenseType", DOS_CONN_DEFENSE_TYPE_DEFAULT, @@ -613,8 +615,8 @@ dos_should_refuse_single_hop_client(void) return 0; }

- if (get_options()->DoSRefuseSingleHopClientRendezvous != -1) { - return get_options()->DoSRefuseSingleHopClientRendezvous; + if (dos_get_options()->DoSRefuseSingleHopClientRendezvous != -1) { + return dos_get_options()->DoSRefuseSingleHopClientRendezvous; }

return (int) networkstatus_get_param(NULL, diff --git a/src/core/or/dos_config.c b/src/core/or/dos_config.c new file mode 100644 index 0000000000..e97c505ea3 --- /dev/null +++ b/src/core/or/dos_config.c @@ -0,0 +1,29 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file dos_config.c + * @brief Code to interpret the user's configuration of DoS module. + **/ + +#include "core/or/dos_config.h" +#include "core/or/dos_options_st.h" + +/* Declare the options field table for dos_options */ +#define CONF_CONTEXT TABLE +#include "core/or/dos_options.inc" +#undef CONF_CONTEXT + +/** Magic number for dos_options_t. */ +#define DOS_OPTIONS_MAGIC 0x91716151 + +/** + * Declare the configuration options for the dos module. + **/ +const config_format_t dos_options_fmt = { + .size = sizeof(dos_options_t), + .magic = { "dos_options_t", + DOS_OPTIONS_MAGIC, + offsetof(dos_options_t, magic) }, + .vars = dos_options_t_vars, +}; diff --git a/src/core/or/dos_config.h b/src/core/or/dos_config.h new file mode 100644 index 0000000000..de8e135aaa --- /dev/null +++ b/src/core/or/dos_config.h @@ -0,0 +1,16 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file dos_config.h + * @brief Header for core/or/dos_config.c + **/ + +#ifndef TOR_CORE_OR_DOS_CONFIG_H +#define TOR_CORE_OR_DOS_CONFIG_H + +#include "lib/conf/conftypes.h" + +extern const struct config_format_t dos_options_fmt; + +#endif /* !defined(TOR_CORE_OR_DOS_CONFIG_H) */ diff --git a/src/core/or/dos_options.inc b/src/core/or/dos_options.inc new file mode 100644 index 0000000000..063a739939 --- /dev/null +++ b/src/core/or/dos_options.inc @@ -0,0 +1,47 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file dos_options.inc + * @brief Declare configuration options for the DoS module. + **/ + +BEGIN_CONF_STRUCT(dos_options_t) + +/** Autobool: Is the DoS connection mitigation subsystem enabled? */ +CONF_VAR(DoSConnectionEnabled, AUTOBOOL, 0, "auto") + +/** Autobool: Is the circuit creation DoS mitigation subsystem enabled? */ +CONF_VAR(DoSCircuitCreationEnabled, AUTOBOOL, 0, "auto") + +/** Minimum concurrent connection needed from one single address before any + * defense is used. */ +CONF_VAR(DoSCircuitCreationMinConnections, POSINT, 0, "0") + +/** Circuit rate used to refill the token bucket. */ +CONF_VAR(DoSCircuitCreationRate, POSINT, 0, "0") + +/** Maximum allowed burst of circuits. Reaching that value, the address is + * detected as malicious and a defense might be used. */ +CONF_VAR(DoSCircuitCreationBurst, POSINT, 0, "0") + +/** When an address is marked as malicious, what defense should be used + * against it. See the dos_cc_defense_type_t enum. */ +CONF_VAR(DoSCircuitCreationDefenseType, INT, 0, "0") + +/** For how much time (in seconds) the defense is applicable for a malicious + * address. A random time delta is added to the defense time of an address + * which will be between 1 second and half of this value. */ +CONF_VAR(DoSCircuitCreationDefenseTimePeriod, INTERVAL, 0, "0") + +/** Maximum concurrent connection allowed per address. */ +CONF_VAR(DoSConnectionMaxConcurrentCount, POSINT, 0, "0") + +/** When an address is reaches the maximum count, what defense should be + * used against it. See the dos_conn_defense_type_t enum. */ +CONF_VAR(DoSConnectionDefenseType, INT, 0, "0") + +/** Autobool: Do we refuse single hop client rendezvous? */ +CONF_VAR(DoSRefuseSingleHopClientRendezvous, AUTOBOOL, 0, "auto") + +END_CONF_STRUCT(dos_options_t) diff --git a/src/core/or/dos_options_st.h b/src/core/or/dos_options_st.h new file mode 100644 index 0000000000..b62bdecc82 --- /dev/null +++ b/src/core/or/dos_options_st.h @@ -0,0 +1,20 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * @file dos_options_st.h + * @brief Structure dos_options_t to hold options for the DoS subsystem. + **/ + +#ifndef TOR_CORE_OR_DOS_OPTIONS_ST_H +#define TOR_CORE_OR_DOS_OPTIONS_ST_H + +#include "lib/conf/confdecl.h" + +#define CONF_CONTEXT STRUCT +#include "core/or/dos_options.inc" +#undef CONF_CONTEXT + +typedef struct dos_options_t dos_options_t; + +#endif /* !defined(TOR_CORE_OR_DOS_OPTIONS_ST_H) */ diff --git a/src/core/or/dos_sys.c b/src/core/or/dos_sys.c index b25d45bc14..cc3b5bf9c6 100644 --- a/src/core/or/dos_sys.c +++ b/src/core/or/dos_sys.c @@ -6,11 +6,17 @@ * @brief Subsystem definitions for DOS module. **/

+#include "core/or/or.h" + #include "lib/subsys/subsys.h"

-#include "core/or/dos.h" +#include "core/or/dos_config.h" #include "core/or/dos_sys.h"

+#include "core/or/dos_options_st.h" + +static const dos_options_t *global_dos_options; + static int subsys_dos_initialize(void) { @@ -20,6 +26,22 @@ subsys_dos_initialize(void) static void subsys_dos_shutdown(void) { + global_dos_options = NULL; +} + +const dos_options_t * +dos_get_options(void) +{ + tor_assert(global_dos_options); + return global_dos_options; +} + +static int +dos_set_options(void *arg) +{ + dos_options_t *opts = arg; + global_dos_options = opts; + return 0; }

const struct subsys_fns_t sys_dos = { @@ -31,4 +53,8 @@ const struct subsys_fns_t sys_dos = {

.initialize = subsys_dos_initialize, .shutdown = subsys_dos_shutdown, + + /* Configuration Options. */ + .options_format = &dos_options_fmt, + .set_options = dos_set_options, }; diff --git a/src/core/or/dos_sys.h b/src/core/or/dos_sys.h index 2c9824a32a..2212d3c707 100644 --- a/src/core/or/dos_sys.h +++ b/src/core/or/dos_sys.h @@ -9,6 +9,9 @@ #ifndef TOR_CORE_OR_DOS_SYS_H #define TOR_CORE_OR_DOS_SYS_H

+struct dos_options_t; +const struct dos_options_t *dos_get_options(void); + extern const struct subsys_fns_t sys_dos;

/** diff --git a/src/core/or/include.am b/src/core/or/include.am index 1308497092..b578b75673 100644 --- a/src/core/or/include.am +++ b/src/core/or/include.am @@ -18,6 +18,7 @@ LIBTOR_APP_A_SOURCES += \ src/core/or/connection_edge.c \ src/core/or/connection_or.c \ src/core/or/dos.c \ + src/core/or/dos_config.c \ src/core/or/dos_sys.c \ src/core/or/extendinfo.c \ src/core/or/onion.c \ @@ -65,6 +66,9 @@ noinst_HEADERS += \ src/core/or/crypt_path_st.h \ src/core/or/destroy_cell_queue_st.h \ src/core/or/dos.h \ + src/core/or/dos_config.h \ + src/core/or/dos_options.inc \ + src/core/or/dos_options_st.h \ src/core/or/dos_sys.h \ src/core/or/edge_connection_st.h \ src/core/or/extendinfo.h \