- tor-commits - lists.torproject.org

[tor/release-0.2.2] Implement __OwningControllerProcess option
by arma＠torproject.org 29 May '11

29 May '11

commit 4b266c6e72254d848b2ca4f594c0b41770104d81 Author: Robert Ransom <rransom.8774(a)gmail.com> Date: Sun May 15 08:23:04 2011 -0700 Implement __OwningControllerProcess option Implements part of feature 3049. --- src/common/Makefile.am | 4 +- src/common/procmon.c | 331 ++++++++++++++++++++++++++++++++++++++++++++++++ src/common/procmon.h | 29 ++++ src/or/config.c | 18 +++ src/or/control.c | 86 +++++++++++++ src/or/control.h | 2 + src/or/or.h | 5 + 7 files changed, 473 insertions(+), 2 deletions(-) diff --git a/src/common/Makefile.am b/src/common/Makefile.am index b1e03cd..8889245 100644 --- a/src/common/Makefile.am +++ b/src/common/Makefile.am @@ -12,11 +12,11 @@ libor_extra_source= endif libor_a_SOURCES = address.c log.c util.c compat.c container.c mempool.c \ - memarea.c util_codedigest.c $(libor_extra_source) + memarea.c util_codedigest.c procmon.c $(libor_extra_source) libor_crypto_a_SOURCES = crypto.c aes.c tortls.c torgzip.c libor_event_a_SOURCES = compat_libevent.c -noinst_HEADERS = address.h torlog.h crypto.h util.h compat.h aes.h torint.h tortls.h strlcpy.c strlcat.c torgzip.h container.h ht.h mempool.h memarea.h ciphers.inc compat_libevent.h tortls_states.h +noinst_HEADERS = address.h torlog.h crypto.h util.h compat.h aes.h torint.h tortls.h strlcpy.c strlcat.c torgzip.h container.h ht.h mempool.h memarea.h procmon.h ciphers.inc compat_libevent.h tortls_states.h common_sha1.i: $(libor_SOURCES) $(libor_crypto_a_SOURCES) $(noinst_HEADERS) if test "@SHA1SUM@" != none; then \ diff --git a/src/common/procmon.c b/src/common/procmon.c new file mode 100644 index 0000000..cee956a --- /dev/null +++ b/src/common/procmon.c @@ -0,0 +1,331 @@ + +/** + * \file procmon.c + * \brief Process-termination monitor functions + **/ + +#include "procmon.h" + +#include "util.h" + +#ifdef HAVE_EVENT2_EVENT_H +#include <event2/event.h> +#else +#include <event.h> +#endif + +#ifdef HAVE_SIGNAL_H +#include <signal.h> +#endif +#ifdef HAVE_ERRNO_H +#include <errno.h> +#endif + +#ifdef MS_WINDOWS +#include <windows.h> + +/* Windows does not define pid_t, but _getpid() returns an int. */ +typedef int pid_t; +#endif + +/* Define to 1 if process-termination monitors on this OS and Libevent + version must poll for process termination themselves. */ +#define PROCMON_POLLS 1 +/* Currently we need to poll in some way on all systems. */ + +#ifdef PROCMON_POLLS +static void tor_process_monitor_poll_cb(int unused1, short unused2, + void *procmon_); +#endif + +/* This struct may contain pointers into the original process + * specifier string, but it should *never* contain anything which + * needs to be freed. */ +struct parsed_process_specifier_t { + pid_t pid; +}; + +/** Parse the process specifier given in process_spec into + * *ppspec. Return 0 on success; return -1 and store an error + * message into *msg on failure. The caller must not free the + * returned error message. */ +static int +parse_process_specifier(const char *process_spec, + struct parsed_process_specifier_t *ppspec, + const char **msg) +{ + long pid_l; + int pid_ok = 0; + char *pspec_next; + + /* If we're lucky, long will turn out to be large enough to hold a + * PID everywhere that Tor runs. */ + pid_l = tor_parse_long(process_spec, 0, 1, LONG_MAX, &pid_ok, &pspec_next); + + /* Reserve room in the ‘process specifier’ for additional + * (platform-specific) identifying information beyond the PID, to + * make our process-existence checks a bit less racy in a future + * version. */ + if ((*pspec_next != 0) && (*pspec_next != ' ') && (*pspec_next != ':')) { + pid_ok = 0; + } + + ppspec->pid = (pid_t)(pid_l); + if (!pid_ok || (pid_l != (long)(ppspec->pid))) { + *msg = "invalid PID"; + goto err; + } + + return 0; + err: + return -1; +} + +struct tor_process_monitor_t { + /** Log domain for warning messages. */ + log_domain_mask_t log_domain; + + /** All systems: The best we can do in general is poll for the + * process's existence by PID periodically, and hope that the kernel + * doesn't reassign the same PID to another process between our + * polls. */ + pid_t pid; + +#ifdef MS_WINDOWS + /** Windows-only: Should we poll hproc? If false, poll pid + * instead. */ + int poll_hproc; + + /** Windows-only: Get a handle to the process (if possible) and + * periodically check whether the process we have a handle to has + * ended. */ + HANDLE hproc; + /* XXX023 We can and should have Libevent watch hproc for us, + * if/when some version of Libevent 2.x can be told to do so. */ +#endif + + /* XXX023 On Linux, we can and should receive the 22nd + * (space-delimited) field (‘starttime’) of /proc/$PID/stat from the + * owning controller and store it, and poll once in a while to see + * whether it has changed -- if so, the kernel has *definitely* + * reassigned the owning controller's PID and we should exit. On + * FreeBSD, we can do the same trick using either the 8th + * space-delimited field of /proc/$PID/status on the seven FBSD + * systems whose admins have mounted procfs, or the start-time field + * of the process-information structure returned by kvmgetprocs() on + * any system. The latter is ickier. */ + /* XXX023 On FreeBSD (and possibly other kqueue systems), we can and + * should arrange to receive EVFILT_PROC NOTE_EXIT notifications for + * pid, so we don't have to do such a heavyweight poll operation in + * order to avoid the PID-reassignment race condition. (We would + * still need to poll our own kqueue periodically until some version + * of Libevent 2.x learns to receive these events for us.) */ + + /** A Libevent event structure, to either poll for the process's + * existence or receive a notification when the process ends. */ + struct event *e; + + /** A callback to be called when the process ends. */ + tor_procmon_callback_t cb; + void *cb_arg; /**< A user-specified pointer to be passed to cb. */ +}; + +/** Verify that the process specifier given in process_spec is + * syntactically valid. Return 0 on success; return -1 and store an + * error message into *msg on failure. The caller must not + * free the returned error message. */ +int +tor_validate_process_specifier(const char *process_spec, + const char **msg) +{ + struct parsed_process_specifier_t ppspec; + + tor_assert(msg != NULL); + *msg = NULL; + + return parse_process_specifier(process_spec, &ppspec, msg); +} + +#ifdef HAVE_EVENT2_EVENT_H +#define PERIODIC_TIMER_FLAGS EV_PERSIST +#else +#define PERIODIC_TIMER_FLAGS (0) +#endif + +static const struct timeval poll_interval_tv = {15, 0}; + +/** Create a process-termination monitor for the process specifier + * given in process_spec. Return a newly allocated + * tor_process_monitor_t on success; return NULL and store an error + * message into *msg on failure. The caller must not free + * the returned error message. + * + * When the monitored process terminates, call + * cb(cb_arg). + */ +tor_process_monitor_t * +tor_process_monitor_new(struct event_base *base, + const char *process_spec, + log_domain_mask_t log_domain, + tor_procmon_callback_t cb, void *cb_arg, + const char **msg) +{ + tor_process_monitor_t *procmon = tor_malloc(sizeof(tor_process_monitor_t)); + struct parsed_process_specifier_t ppspec; + + tor_assert(msg != NULL); + *msg = NULL; + + if (procmon == NULL) { + *msg = "out of memory"; + goto err; + } + + procmon->log_domain = log_domain; + + if (parse_process_specifier(process_spec, &ppspec, msg)) + goto err; + + procmon->pid = ppspec.pid; + +#ifdef MS_WINDOWS + procmon->hproc = OpenProcess(PROCESS_QUERY_INFORMATION | SYNCHRONIZE, + FALSE, + procmon->pid); + + if (procmon->hproc != NULL) { + procmon->poll_hproc = 1; + log_info(procmon->log_domain, "Successfully opened handle to process %d; " + "monitoring it.", + (int)(procmon->pid)); + } else { + /* If we couldn't get a handle to the process, we'll try again the + * first time we poll. */ + log_info(procmon->log_domain, "Failed to open handle to process %d; will " + "try again later.", + (int)(procmon->pid)); + } +#endif + + procmon->cb = cb; + procmon->cb_arg = cb_arg; + +#ifdef PROCMON_POLLS + procmon->e = tor_event_new(base, -1 /* no FD */, PERIODIC_TIMER_FLAGS, + tor_process_monitor_poll_cb, procmon); + /* Note: If you port this file to plain Libevent 2, check that + * procmon->e is non-NULL. We don't need to here because + * tor_evtimer_new never returns NULL. */ + + evtimer_add(procmon->e, &poll_interval_tv); +#else +#error OOPS? +#endif + + return procmon; + err: + tor_process_monitor_free(procmon); + return NULL; +} + +#ifdef PROCMON_POLLS +/** Libevent callback to poll for the existence of the process + * monitored by procmon_. */ +static void +tor_process_monitor_poll_cb(int unused1, short unused2, void *procmon_) +{ + tor_process_monitor_t *procmon = (tor_process_monitor_t *)(procmon_); + int its_dead_jim; + + (void)unused1; (void)unused2; + + tor_assert(procmon != NULL); + +#ifdef MS_WINDOWS + if (procmon->poll_hproc) { + DWORD exit_code; + if (!GetExitCodeProcess(procmon->hproc, &exit_code)) { + char *errmsg = format_win32_error(GetLastError()); + log_warn(procmon->log_domain, "Error \"%s\" occurred while polling " + "handle for monitored process %d; assuming it's dead." + errmsg, procmon->pid); + tor_free(errmsg); + its_dead_jim = 1; + } else { + its_dead_jim = (exit_code != STILL_ACTIVE); + } + } else { + /* All we can do is try to open the process, and look at the error + * code if it fails again. */ + procmon->hproc = OpenProcess(PROCESS_QUERY_INFORMATION | SYNCHRONIZE, + FALSE, + procmon->pid); + + if (procmon->hproc != NULL) { + log_info(procmon->log_domain, "Successfully opened handle to monitored " + "process %d.", + procmon->pid); + its_dead_jim = 0; + procmon->poll_hproc = 1; + } else { + DWORD err_code = GetLastError(); + char *errmsg = format_win32_error(err_code); + + /* When I tested OpenProcess's error codes on Windows 7, I + * received error code 5 (ERROR_ACCESS_DENIED) for PIDs of + * existing processes that I could not open and error code 87 + * (ERROR_INVALID_PARAMETER) for PIDs that were not in use. + * Since the nonexistent-process error code is sane, I'm going + * to assume that all errors other than ERROR_INVALID_PARAMETER + * mean that the process we are monitoring is still alive. */ + its_dead_jim = (err_code == ERROR_INVALID_PARAMETER); + + if (!its_dead_jim) + log_info(procmon->log_domain, "Failed to open handle to monitored " + "process %d, and error code %d (%s) is not 'invalid " + "parameter' -- assuming the process is still alive.", + procmon->pid, + err_code, err_msg); + + tor_free(err_msg); + } + } +#else + /* Unix makes this part easy, if a bit racy. */ + its_dead_jim = kill(procmon->pid, 0); + its_dead_jim = its_dead_jim && (errno == ESRCH); +#endif + + log(its_dead_jim ? LOG_NOTICE : LOG_INFO, + procmon->log_domain, "Monitored process %d is %s.", + (int)procmon->pid, + its_dead_jim ? "dead" : "still alive"); + + if (its_dead_jim) { + procmon->cb(procmon->cb_arg); +#ifndef HAVE_EVENT2_EVENT_H + } else { + evtimer_add(procmon->e, &poll_interval_tv); +#endif + } +} +#endif + +/** Free the process-termination monitor procmon. */ +void +tor_process_monitor_free(tor_process_monitor_t *procmon) +{ + if (procmon == NULL) + return; + +#ifdef MS_WINDOWS + if (procmon->hproc != NULL) + CloseHandle(procmon->hproc); +#endif + + if (procmon->e != NULL) + tor_event_free(procmon->e); + + tor_free(procmon); +} + diff --git a/src/common/procmon.h b/src/common/procmon.h new file mode 100644 index 0000000..f8c7444 --- /dev/null +++ b/src/common/procmon.h @@ -0,0 +1,29 @@ + +/** + * \file procmon.h + * \brief Headers for procmon.c + **/ + +#ifndef TOR_PROCMON_H +#define TOR_PROCMON_H + +#include "compat.h" +#include "compat_libevent.h" + +#include "torlog.h" + +typedef struct tor_process_monitor_t tor_process_monitor_t; + +typedef void (*tor_procmon_callback_t)(void *); + +int tor_validate_process_specifier(const char *process_spec, + const char **msg); +tor_process_monitor_t *tor_process_monitor_new(struct event_base *base, + const char *process_spec, + log_domain_mask_t log_domain, + tor_procmon_callback_t cb, + void *cb_arg, + const char **msg); +void tor_process_monitor_free(tor_process_monitor_t *procmon); + +#endif diff --git a/src/or/config.c b/src/or/config.c index 34208e8..b2bc9f3 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -38,6 +38,8 @@ #include <shlobj.h> #endif +#include "procmon.h" + /** Enumeration of types which option values can take */ typedef enum config_type_t { CONFIG_TYPE_STRING = 0, /**< An arbitrary string. */ @@ -393,6 +395,7 @@ static config_var_t _option_vars[] = { VAR("__LeaveStreamsUnattached",BOOL, LeaveStreamsUnattached, "0"), VAR("__HashedControlSessionPassword", LINELIST, HashedControlSessionPassword, NULL), + VAR("__OwningControllerProcess",STRING,OwningControllerProcess, NULL), V(MinUptimeHidServDirectoryV2, INTERVAL, "24 hours"), V(_UsingTestNetworkDefaults, BOOL, "0"), @@ -1229,6 +1232,11 @@ options_act(or_options_t *old_options) return -1; } + if (monitor_owning_controller_process(options->OwningControllerProcess)) { + log_warn(LD_CONFIG, "Error monitoring owning controller process"); + return -1; + } + /* reload keys as needed for rendezvous services. */ if (rend_service_load_keys()<0) { log_warn(LD_GENERAL,"Error loading rendezvous service keys"); @@ -3446,6 +3454,16 @@ options_validate(or_options_t *old_options, or_options_t *options, } } + if (options->OwningControllerProcess) { + const char *validate_pspec_msg = NULL; + if (tor_validate_process_specifier(options->OwningControllerProcess, + &validate_pspec_msg)) { + tor_asprintf(msg, "Bad OwningControllerProcess: %s", + validate_pspec_msg); + return -1; + } + } + if (options->ControlListenAddress) { int all_are_local = 1; config_line_t *ln; diff --git a/src/or/control.c b/src/or/control.c index 926a465..3a96904 100644 --- a/src/or/control.c +++ b/src/or/control.c @@ -32,6 +32,8 @@ #include "routerlist.h" #include "routerparse.h" +#include "procmon.h" + /** Yield true iff s is the state of a control_connection_t that has * finished authentication and is accepting commands. */ #define STATE_IS_OPEN(s) ((s) == CONTROL_CONN_STATE_OPEN) @@ -3779,6 +3781,90 @@ init_cookie_authentication(int enabled) return 0; } +/** A copy of the process specifier of Tor's owning controller, or + * NULL if this Tor instance is not currently owned by a process. */ +static char *owning_controller_process_spec = NULL; + +/** A process-termination monitor for Tor's owning controller, or NULL + * if this Tor instance is not currently owned by a process. */ +static tor_process_monitor_t *owning_controller_process_monitor = NULL; + +/** Process-termination monitor callback for Tor's owning controller + * process. */ +static void +owning_controller_procmon_cb(void *unused) +{ + int shutdown_slowly = server_mode(get_options()); + + (void)unused; + + log_notice(LD_CONTROL, "Owning controller process has vanished -- " + "%s.", + shutdown_slowly ? "shutting down" : "exiting now"); + + /* XXXX This chunk of code should be a separate function, called + * here and by process_signal(SIGINT). */ + + if (!shutdown_slowly) { + tor_cleanup(); + exit(0); + } + /* XXXX This will close all listening sockets except control-port + * listeners. Perhaps we should close those too. */ + hibernate_begin_shutdown(); +} + +/** Set process_spec as Tor's owning controller process. + * Return 0 on success, -1 on failure. */ +int +monitor_owning_controller_process(const char *process_spec) +{ + const char *msg; + + tor_assert((owning_controller_process_spec == NULL) == + (owning_controller_process_monitor == NULL)); + + if (owning_controller_process_spec != NULL) { + if ((process_spec != NULL) && !strcmp(process_spec, + owning_controller_process_spec)) { + /* Same process -- return now, instead of disposing of and + * recreating the process-termination monitor. */ + return 0; + } + + /* We are currently owned by a process, and we should no longer be + * owned by it. Free the process-termination monitor. */ + tor_process_monitor_free(owning_controller_process_monitor); + owning_controller_process_monitor = NULL; + + tor_free(owning_controller_process_spec); + owning_controller_process_spec = NULL; + } + + tor_assert((owning_controller_process_spec == NULL) && + (owning_controller_process_monitor == NULL)); + + if (process_spec == NULL) + return 0; + + owning_controller_process_spec = tor_strdup(process_spec); + owning_controller_process_monitor = + tor_process_monitor_new(tor_libevent_get_base(), + owning_controller_process_spec, + LD_CONTROL, + owning_controller_procmon_cb, NULL, + &msg); + + if (owning_controller_process_monitor == NULL) { + log_warn(LD_CONTROL, "Couldn't create process-termination monitor for " + "owning controller: %s", + msg); + return -1; + } + + return 0; +} + /** Convert the name of a bootstrapping phase s into strings * tag and summary suitable for display by the controller. */ static int diff --git a/src/or/control.h b/src/or/control.h index 2ae96b4..81c2301 100644 --- a/src/or/control.h +++ b/src/or/control.h @@ -70,6 +70,8 @@ smartlist_t *decode_hashed_passwords(config_line_t *passwords); void disable_control_logging(void); void enable_control_logging(void); +int monitor_owning_controller_process(const char *process_spec); + void control_event_bootstrap(bootstrap_status_t status, int progress); void control_event_bootstrap_problem(const char *warn, int reason); diff --git a/src/or/or.h b/src/or/or.h index d667358..546c38a 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -2669,6 +2669,11 @@ typedef struct { int DisablePredictedCircuits; /**< Boolean: does Tor preemptively * make circuits in the background (0), * or not (1)? */ + + /** Process specifier for a controller that ‘owns’ this Tor + * instance. Tor will terminate if its owning controller does. */ + char *OwningControllerProcess; + int ShutdownWaitLength; /**< When we get a SIGINT and we're a server, how * long do we wait before exiting? */ char *SafeLogging; /**< Contains "relay", "1", "0" (meaning no scrubbing). */

1 0

[obfsproxy/master] Implement functional shared secret support.
by nickm＠torproject.org 29 May '11

29 May '11

commit c6a369e197cae2e677106ac2b126abcfdaed6a43 Author: George Kadianakis <desnacked(a)gmail.com> Date: Tue May 17 03:05:42 2011 +0200 Implement functional shared secret support. --- src/main.c | 37 ++++++++++++++++++++++--------------- src/network.c | 30 ++++++++++++++---------------- src/network.h | 2 +- src/protocol.c | 6 +++--- src/protocol.h | 40 ++++++++++++++++++++++++---------------- src/protocols/dummy.c | 4 +++- src/protocols/dummy.h | 2 +- src/protocols/obfs2.c | 30 ++++++++++++++++++++++-------- src/protocols/obfs2.h | 4 +--- src/test/unittest.c | 2 +- src/test/unittest_obfs2.c | 2 ++ 11 files changed, 94 insertions(+), 65 deletions(-) diff --git a/src/main.c b/src/main.c index 225c698..1c084d3 100644 --- a/src/main.c +++ b/src/main.c @@ -25,7 +25,7 @@ static void usage(void) { fprintf(stderr, - "Usage: obfsproxy {client/server/socks} {obfs2/dummy} listenaddr[:port] targetaddr:port\n" + "Usage: obfsproxy {client/server/socks} {obfs2/dummy} listenaddr[:port] targetaddr:port <shared secret>\n" " (Default listen port is 48988 for client; 23548 for socks; 11253 for server)\n" ); exit(1); @@ -49,6 +49,7 @@ main(int argc, const char **argv) struct sockaddr *sa_target=NULL; int sl_listen, sl_target=0; const char *defport; + char *shared_secret = NULL; struct event_base *base; struct event *sigevent; @@ -85,19 +86,25 @@ main(int argc, const char **argv) if (resolve_address_port(argv[3], 1, 1, &ss_listen, &sl_listen, defport) < 0) usage(); - if (is_socks) { - if (argc != 4) - usage(); - } else { - if (argc != 5) - usage(); - - /* figure out what place to connect to as a client/server. */ - /* XXXX when we add socks support, clients will not have a fixed "target" - * XXXX address but will instead connect to a client-selected address. */ - if (resolve_address_port(argv[4], 1, 0, &ss_target, &sl_target, NULL) < 0) - usage(); - sa_target = (struct sockaddr *)&ss_target; + /* figure out what place to connect to as a client/server. */ + /* XXXX when we add socks support, clients will not have a fixed "target" + * XXXX address but will instead connect to a client-selected address. */ + if (resolve_address_port(argv[4], 1, 0, &ss_target, &sl_target, NULL) < 0) + usage(); + sa_target = (struct sockaddr *)&ss_target; + + /* Let's see if the user wants a shared secret. + So ugly. So ugly. So ugly. So ugly. So ugly interface. + */ + if (argc > 5 && argc != 6) + usage(); + if (argc == 6) { + if (protocol != OBFS2_PROTOCOL) { + printf("shared secret is only supported with obfs2 atm.\n"); + exit(1); + } + + shared_secret = strdup(argv[5]); } /* Initialize libevent */ @@ -121,7 +128,7 @@ main(int argc, const char **argv) mode, protocol, (struct sockaddr *)&ss_listen, sl_listen, sa_target, sl_target, - NULL, 0); + shared_secret); if (! listener) { printf("Couldn't create listener!\n"); return 4; diff --git a/src/network.c b/src/network.c index b0106de..a32cb1d 100644 --- a/src/network.c +++ b/src/network.c @@ -29,10 +29,8 @@ struct listener_t { int target_address_len; int proto; /* Protocol that this listener can speak. */ int mode; - /* ASN */ - /* char shared_secret[SHARED_SECRET_LENGTH]; + const char *shared_secret; unsigned int have_shared_secret : 1; - */ }; static void simple_listener_cb(struct evconnlistener *evcl, @@ -54,7 +52,7 @@ listener_new(struct event_base *base, int mode, int protocol, const struct sockaddr *on_address, int on_address_len, const struct sockaddr *target_address, int target_address_len, - const char *shared_secret, size_t shared_secret_len) + const char *shared_secret) { const unsigned flags = LEV_OPT_CLOSE_ON_FREE|LEV_OPT_CLOSE_ON_EXEC|LEV_OPT_REUSEABLE; @@ -70,6 +68,8 @@ listener_new(struct event_base *base, lsn->proto = protocol; lsn->mode = mode; + lsn->shared_secret = shared_secret; + lsn->have_shared_secret = 1; if (target_address) { assert(target_address_len <= sizeof(struct sockaddr_storage)); @@ -79,15 +79,6 @@ listener_new(struct event_base *base, assert(lsn->mode == LSN_SOCKS_CLIENT); } - /* ASN */ - /* - assert(shared_secret == NULL || shared_secret_len == SHARED_SECRET_LENGTH); - if (shared_secret) { - memcpy(lsn->shared_secret, shared_secret, SHARED_SECRET_LENGTH); - lsn->have_shared_secret = 1; - } - */ - lsn->listener = evconnlistener_new_bind(base, simple_listener_cb, lsn, flags, -1, @@ -124,10 +115,17 @@ simple_listener_cb(struct evconnlistener *evcl, conn->mode = lsn->mode; - /* Will all protocols need to _init() here? Don't think so! */ + struct protocol_params_t *proto_params = calloc(1, sizeof(struct protocol_params_t)); + proto_params->is_initiator = conn->mode != LSN_SIMPLE_SERVER; + proto_params->shared_secret = lsn->shared_secret; + conn->proto = proto_new(lsn->proto, - conn->mode != LSN_SIMPLE_SERVER); - + proto_params); + if (!conn->proto) { + printf("Creation of protocol object failed! Closing connection.\n"); + goto err; + } + if (conn->mode == LSN_SOCKS_CLIENT) { /* Construct SOCKS state. */ conn->socks_state = socks_state_new(); diff --git a/src/network.h b/src/network.h index 619e45f..1e13cb4 100644 --- a/src/network.h +++ b/src/network.h @@ -28,7 +28,7 @@ listener_t *listener_new( int mode, int protocol, const struct sockaddr *on_address, int on_address_len, const struct sockaddr *target_address, int target_address_len, - const char *shared_secret, size_t shared_secret_len); + const char *shared_secret); void listener_free(listener_t *listener); #ifdef NETWORK_PRIVATE diff --git a/src/protocol.c b/src/protocol.c index 1fbd3f7..b371923 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -31,7 +31,7 @@ set_up_protocol(int protocol) { Return the protocol_t if successful, NULL otherwise. */ struct protocol_t * -proto_new(int protocol, int is_initiator) { +proto_new(int protocol, struct protocol_params_t *params) { struct protocol_t *proto = calloc(1, sizeof(struct protocol_t)); if (!proto) return NULL; @@ -42,10 +42,10 @@ proto_new(int protocol, int is_initiator) { if (protocol == OBFS2_PROTOCOL) { proto->proto = protocol; - proto->state = obfs2_new(proto, is_initiator); + proto->state = obfs2_new(proto, params->is_initiator, params->shared_secret); } else if (protocol == DUMMY_PROTOCOL) { proto->proto = protocol; - proto->state = dummy_new(proto, is_initiator); + proto->state = dummy_new(proto, 666, NULL); } if (proto->state) diff --git a/src/protocol.h b/src/protocol.h index dd34585..7d0fb44 100644 --- a/src/protocol.h +++ b/src/protocol.h @@ -6,12 +6,16 @@ struct evbuffer; -int set_up_protocol(int protocol); -struct protocol_t *proto_new(int protocol, int arg); -void proto_destroy(struct protocol_t *proto); -int proto_handshake(struct protocol_t *proto, void *buf); -int proto_send(struct protocol_t *proto, void *source, void *dest); -int proto_recv(struct protocol_t *proto, void *source, void *dest); +struct protocol_t { + /* protocol */ + int proto; + + /* protocol vtable */ + struct protocol_vtable *vtable; + + /* ASN do we need a proto_get_state()? */ + void *state; +}; typedef struct protocol_vtable { @@ -22,7 +26,7 @@ typedef struct protocol_vtable { /* Constructor: Creates a protocol object. */ void *(*create)(struct protocol_t *proto_struct, - int is_initiator); + int is_initiator, const char *parameters); /* does handshake. Not all protocols have a handshake. */ int (*handshake)(void *state, @@ -37,17 +41,21 @@ typedef struct protocol_vtable { int (*recv)(void *state, struct evbuffer *source, struct evbuffer *dest); -} protocol_vtable; -struct protocol_t { - /* protocol */ - int proto; - - /* protocol vtable */ - protocol_vtable *vtable; +} protocol_vtable; - /* ASN do we need a proto_get_state()? */ - void *state; +struct protocol_params_t { + int is_initiator; + + const char *shared_secret; }; +int set_up_protocol(int protocol); +struct protocol_t *proto_new(int protocol, + struct protocol_params_t *params); +void proto_destroy(struct protocol_t *proto); +int proto_handshake(struct protocol_t *proto, void *buf); +int proto_send(struct protocol_t *proto, void *source, void *dest); +int proto_recv(struct protocol_t *proto, void *source, void *dest); + #endif diff --git a/src/protocols/dummy.c b/src/protocols/dummy.c index 8fe722e..f5a7558 100644 --- a/src/protocols/dummy.c +++ b/src/protocols/dummy.c @@ -36,8 +36,10 @@ dummy_init(void) { } void * -dummy_new(struct protocol_t *proto_struct, int whatever) { +dummy_new(struct protocol_t *proto_struct, int whatever, + const char *whatever2) { (void)whatever; + (void)whatever2; proto_struct->vtable = vtable; diff --git a/src/protocols/dummy.h b/src/protocols/dummy.h index 241366d..5ab39a4 100644 --- a/src/protocols/dummy.h +++ b/src/protocols/dummy.h @@ -5,6 +5,6 @@ struct protocol_t; struct evbuffer; int dummy_init(void); -void *dummy_new(struct protocol_t *proto_struct, int whatever); +void *dummy_new(struct protocol_t *proto_struct, int whatever, const char* whatever2); #endif diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index cac7bb2..aba8ea9 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -26,7 +26,9 @@ static int obfs2_send(void *state, struct evbuffer *source, struct evbuffer *dest); static int obfs2_recv(void *state, struct evbuffer *source, struct evbuffer *dest); -static void *obfs2_state_new(int initiator); +static void *obfs2_state_new(int initiator, const char *shared_secret); +static int obfs2_state_set_shared_secret(void *s, + const char *secret); static protocol_vtable *vtable=NULL; @@ -113,11 +115,11 @@ derive_padding_key(void *s, const uchar *seed, } void * -obfs2_new(struct protocol_t *proto_struct, int initiator) { +obfs2_new(struct protocol_t *proto_struct, int initiator, const char *shared_secret) { assert(vtable); proto_struct->vtable = vtable; - return obfs2_state_new(initiator); + return obfs2_state_new(initiator, shared_secret); } /** @@ -126,7 +128,7 @@ obfs2_new(struct protocol_t *proto_struct, int initiator) { NULL on failure. */ static void * -obfs2_state_new(int initiator) +obfs2_state_new(int initiator, const char *shared_secret) { obfs2_state_t *state = calloc(1, sizeof(obfs2_state_t)); uchar *seed; @@ -150,6 +152,9 @@ obfs2_state_new(int initiator) return NULL; } + if (shared_secret) + obfs2_state_set_shared_secret(state, shared_secret); + /* Derive the key for what we're sending */ state->send_padding_crypto = derive_padding_key(state, seed, send_pad_type); if (state->send_padding_crypto == NULL) { @@ -161,15 +166,25 @@ obfs2_state_new(int initiator) } /** Set the shared secret to be used with this protocol state. */ -void +static int obfs2_state_set_shared_secret(void *s, - const char *secret, size_t secretlen) + const char *secret) { + assert(secret); obfs2_state_t *state = s; + size_t secretlen = strlen(secret); - if (secretlen > SHARED_SECRET_LENGTH) + if (secretlen < SHARED_SECRET_LENGTH) { + printf("Shared secrets must be at least 16 bytes.\n"); /* Why? */ + return -1; + } else if (secretlen > SHARED_SECRET_LENGTH) secretlen = SHARED_SECRET_LENGTH; + memcpy(state->secret_seed, secret, secretlen); + + /* free(secret); */ + + return 0; } /** @@ -232,7 +247,6 @@ crypt_and_transmit(crypt_t *crypto, if (n <= 0) return 0; stream_crypt(crypto, data, n); - // printf("Message is: %s", data); evbuffer_add(dest, data, n); dbg(("Processed %d bytes.", n)); } diff --git a/src/protocols/obfs2.h b/src/protocols/obfs2.h index 3124bbc..bcc423f 100644 --- a/src/protocols/obfs2.h +++ b/src/protocols/obfs2.h @@ -16,10 +16,8 @@ struct protocol_t; #define SHARED_SECRET_LENGTH 16 -void obfs2_state_set_shared_secret(void *state, - const char *secret, size_t secretlen); int obfs2_init(void); -void *obfs2_new(struct protocol_t *proto_struct, int initiator); +void *obfs2_new(struct protocol_t *proto_struct, int initiator, const char *parameters); #ifdef CRYPT_PROTOCOL_PRIVATE diff --git a/src/test/unittest.c b/src/test/unittest.c index 41159ca..9ca6a74 100644 --- a/src/test/unittest.c +++ b/src/test/unittest.c @@ -15,7 +15,7 @@ extern struct testcase_t socks_tests[]; struct testgroup_t groups[] = { { "crypt/", crypt_tests }, - { "proto/", protocol_tests }, + /* { "proto/", protocol_tests }, */ { "socks/", socks_tests }, END_OF_GROUPS }; diff --git a/src/test/unittest_obfs2.c b/src/test/unittest_obfs2.c index f006b2f..ce743c8 100644 --- a/src/test/unittest_obfs2.c +++ b/src/test/unittest_obfs2.c @@ -1,3 +1,4 @@ +#if 0 /* Copyright 2011 Nick Mathewson You may do anything with this work that copyright law would normally @@ -474,3 +475,4 @@ struct testcase_t protocol_tests[] = { T(wrong_handshake_plength, 0), END_OF_TESTCASES }; +#endif

1 0

[obfsproxy/master] Improved shared secret support based on the comments of my Mentor in #3202.
by nickm＠torproject.org 29 May '11

29 May '11

commit 536e014a102d283f668dbfd75bdd56de2728bc87 Author: George Kadianakis <desnacked(a)gmail.com> Date: Tue May 24 16:06:33 2011 +0200 Improved shared secret support based on the comments of my Mentor in #3202. Specifically: * We stop stupidly treating the shared secret as a C-string. We now instead hash it. We don't iteratively hash it yet. * Because of hashing the shared secret, we now allow shared secrets of arbitrary length. * We now pass protocol_params_t structs to the _new protocol methods. It looks/is much nicer. * I better defined the role of the protocol_params_t struct and is now attached to the listener_t struct. This is not done yet. --- src/main.c | 2 +- src/network.c | 32 +++++++++++++++++++++----------- src/network.h | 2 +- src/protocol.c | 4 ++-- src/protocol.h | 33 +++++++++++++++++++++++++-------- src/protocols/dummy.c | 8 +++----- src/protocols/dummy.h | 3 ++- src/protocols/obfs2.c | 46 ++++++++++++++++++++++++++-------------------- src/protocols/obfs2.h | 7 +++++-- 9 files changed, 86 insertions(+), 51 deletions(-) diff --git a/src/main.c b/src/main.c index 1c084d3..59b6909 100644 --- a/src/main.c +++ b/src/main.c @@ -128,7 +128,7 @@ main(int argc, const char **argv) mode, protocol, (struct sockaddr *)&ss_listen, sl_listen, sa_target, sl_target, - shared_secret); + shared_secret, strlen(shared_secret)); if (! listener) { printf("Couldn't create listener!\n"); return 4; diff --git a/src/network.c b/src/network.c index a32cb1d..07efbc4 100644 --- a/src/network.c +++ b/src/network.c @@ -27,10 +27,9 @@ struct listener_t { struct evconnlistener *listener; struct sockaddr_storage target_address; int target_address_len; - int proto; /* Protocol that this listener can speak. */ int mode; - const char *shared_secret; - unsigned int have_shared_secret : 1; + int proto; /* Protocol that this listener can speak. */ + struct protocol_params_t *proto_params; }; static void simple_listener_cb(struct evconnlistener *evcl, @@ -52,7 +51,7 @@ listener_new(struct event_base *base, int mode, int protocol, const struct sockaddr *on_address, int on_address_len, const struct sockaddr *target_address, int target_address_len, - const char *shared_secret) + const char *shared_secret, size_t shared_secret_len) { const unsigned flags = LEV_OPT_CLOSE_ON_FREE|LEV_OPT_CLOSE_ON_EXEC|LEV_OPT_REUSEABLE; @@ -68,8 +67,13 @@ listener_new(struct event_base *base, lsn->proto = protocol; lsn->mode = mode; - lsn->shared_secret = shared_secret; - lsn->have_shared_secret = 1; + + struct protocol_params_t *proto_params = calloc(1, sizeof(struct protocol_params_t)); + proto_params->is_initiator = mode != LSN_SIMPLE_SERVER; + proto_params->shared_secret = shared_secret; + proto_params->shared_secret_len = shared_secret_len; + + lsn->proto_params = proto_params; if (target_address) { assert(target_address_len <= sizeof(struct sockaddr_storage)); @@ -92,11 +96,21 @@ listener_new(struct event_base *base, return lsn; } +static void +protocol_params_free(struct protocol_params_t *params) +{ + assert(params); + if (params->shared_secret) + free(&params->shared_secret); +} + void listener_free(listener_t *lsn) { if (lsn->listener) evconnlistener_free(lsn->listener); + if (lsn->proto_params) + protocol_params_free(lsn->proto_params); memset(lsn, 0xb0, sizeof(listener_t)); free(lsn); } @@ -115,12 +129,8 @@ simple_listener_cb(struct evconnlistener *evcl, conn->mode = lsn->mode; - struct protocol_params_t *proto_params = calloc(1, sizeof(struct protocol_params_t)); - proto_params->is_initiator = conn->mode != LSN_SIMPLE_SERVER; - proto_params->shared_secret = lsn->shared_secret; - conn->proto = proto_new(lsn->proto, - proto_params); + lsn->proto_params); if (!conn->proto) { printf("Creation of protocol object failed! Closing connection.\n"); goto err; diff --git a/src/network.h b/src/network.h index 1e13cb4..619e45f 100644 --- a/src/network.h +++ b/src/network.h @@ -28,7 +28,7 @@ listener_t *listener_new( int mode, int protocol, const struct sockaddr *on_address, int on_address_len, const struct sockaddr *target_address, int target_address_len, - const char *shared_secret); + const char *shared_secret, size_t shared_secret_len); void listener_free(listener_t *listener); #ifdef NETWORK_PRIVATE diff --git a/src/protocol.c b/src/protocol.c index b371923..4e6ae81 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -42,10 +42,10 @@ proto_new(int protocol, struct protocol_params_t *params) { if (protocol == OBFS2_PROTOCOL) { proto->proto = protocol; - proto->state = obfs2_new(proto, params->is_initiator, params->shared_secret); + proto->state = obfs2_new(proto, params); } else if (protocol == DUMMY_PROTOCOL) { proto->proto = protocol; - proto->state = dummy_new(proto, 666, NULL); + proto->state = dummy_new(proto, NULL); } if (proto->state) diff --git a/src/protocol.h b/src/protocol.h index 7d0fb44..6b609ee 100644 --- a/src/protocol.h +++ b/src/protocol.h @@ -6,14 +6,37 @@ struct evbuffer; +/** + This struct defines parameters of the protocol per-listener basis. + + By 'per-listener basis' I mean that the parameters defined here will + be inherited by *all* connections opened from the listener_t that + owns this protocol_params_t. +*/ +struct protocol_params_t { +int is_initiator; + + const char *shared_secret; + size_t shared_secret_len; +}; + struct protocol_t { /* protocol */ int proto; /* protocol vtable */ struct protocol_vtable *vtable; + + /* This protocol specific struct defines the state of the protocol + per-connection basis. - /* ASN do we need a proto_get_state()? */ + By 'protocol specific' I mean that every protocol has it's own + state struct. (for example, obfs2 has obfs2_state_t) + + By 'per-connection basis' I mean that the every connection has a + different protocol_t struct, and that's precisely the reason that + this struct is owned by the conn_t struct. + */ void *state; }; @@ -26,7 +49,7 @@ typedef struct protocol_vtable { /* Constructor: Creates a protocol object. */ void *(*create)(struct protocol_t *proto_struct, - int is_initiator, const char *parameters); + struct protocol_params_t *parameters); /* does handshake. Not all protocols have a handshake. */ int (*handshake)(void *state, @@ -44,12 +67,6 @@ typedef struct protocol_vtable { } protocol_vtable; -struct protocol_params_t { - int is_initiator; - - const char *shared_secret; -}; - int set_up_protocol(int protocol); struct protocol_t *proto_new(int protocol, struct protocol_params_t *params); diff --git a/src/protocols/dummy.c b/src/protocols/dummy.c index f5a7558..79d40e0 100644 --- a/src/protocols/dummy.c +++ b/src/protocols/dummy.c @@ -36,11 +36,9 @@ dummy_init(void) { } void * -dummy_new(struct protocol_t *proto_struct, int whatever, - const char *whatever2) { - (void)whatever; - (void)whatever2; - +dummy_new(struct protocol_t *proto_struct, + struct protocol_params_t *params) +{ proto_struct->vtable = vtable; /* Dodging state check. diff --git a/src/protocols/dummy.h b/src/protocols/dummy.h index 5ab39a4..1ee0e02 100644 --- a/src/protocols/dummy.h +++ b/src/protocols/dummy.h @@ -3,8 +3,9 @@ struct protocol_t; struct evbuffer; +struct protocol_params_t; int dummy_init(void); -void *dummy_new(struct protocol_t *proto_struct, int whatever, const char* whatever2); +void *dummy_new(struct protocol_t *proto_struct, struct protocol_params_t *params); #endif diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index fe50553..277ca63 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -26,9 +26,10 @@ static int obfs2_send(void *state, struct evbuffer *source, struct evbuffer *dest); static int obfs2_recv(void *state, struct evbuffer *source, struct evbuffer *dest); -static void *obfs2_state_new(int initiator, const char *shared_secret); +static void *obfs2_state_new(struct protocol_params_t *params); static int obfs2_state_set_shared_secret(void *s, - const char *secret); + const char *secret, + size_t secretlen); static protocol_vtable *vtable=NULL; @@ -115,11 +116,13 @@ derive_padding_key(void *s, const uchar *seed, } void * -obfs2_new(struct protocol_t *proto_struct, int initiator, const char *shared_secret) { +obfs2_new(struct protocol_t *proto_struct, + struct protocol_params_t *params) +{ assert(vtable); proto_struct->vtable = vtable; - return obfs2_state_new(initiator, shared_secret); + return obfs2_state_new(params); } /** @@ -128,7 +131,7 @@ obfs2_new(struct protocol_t *proto_struct, int initiator, const char *shared_sec NULL on failure. */ static void * -obfs2_state_new(int initiator, const char *shared_secret) +obfs2_state_new(struct protocol_params_t *params) { obfs2_state_t *state = calloc(1, sizeof(obfs2_state_t)); uchar *seed; @@ -137,8 +140,8 @@ obfs2_state_new(int initiator, const char *shared_secret) if (!state) return NULL; state->state = ST_WAIT_FOR_KEY; - state->we_are_initiator = initiator; - if (initiator) { + state->we_are_initiator = params->is_initiator; + if (state->we_are_initiator) { send_pad_type = INITIATOR_PAD_TYPE; seed = state->initiator_seed; } else { @@ -152,8 +155,10 @@ obfs2_state_new(int initiator, const char *shared_secret) return NULL; } - if (shared_secret) - if (obfs2_state_set_shared_secret(state, shared_secret)<0) + if (params->shared_secret) + if (obfs2_state_set_shared_secret(state, + params->shared_secret, + params->shared_secret_len)<0) return NULL; /* Derive the key for what we're sending */ @@ -168,22 +173,23 @@ obfs2_state_new(int initiator, const char *shared_secret) /** Set the shared secret to be used with this protocol state. */ static int -obfs2_state_set_shared_secret(void *s, - const char *secret) +obfs2_state_set_shared_secret(void *s, const char *secret, + size_t secretlen) { assert(secret); - obfs2_state_t *state = s; - size_t secretlen = strlen(secret); + assert(secretlen); - if (secretlen < SHARED_SECRET_LENGTH) { - printf("Shared secrets must be at least 16 bytes.\n"); /* Why? */ - return -1; - } else if (secretlen > SHARED_SECRET_LENGTH) - secretlen = SHARED_SECRET_LENGTH; + uchar buf[SHARED_SECRET_LENGTH]; + obfs2_state_t *state = s; - memcpy(state->secret_seed, secret, secretlen); + digest_t *c = digest_new(); + /* ASN do we like this cast here? */ + digest_update(c, (uchar*)secret, secretlen); + digest_getdigest(c, buf, sizeof(buf)); + memcpy(state->secret_seed, buf, SHARED_SECRET_LENGTH); - /* free(secret); */ + memset(buf,0,SHARED_SECRET_LENGTH); + digest_free(c); return 0; } diff --git a/src/protocols/obfs2.h b/src/protocols/obfs2.h index bcc423f..bc8a22d 100644 --- a/src/protocols/obfs2.h +++ b/src/protocols/obfs2.h @@ -13,11 +13,14 @@ typedef struct obfs2_state_t obfs2_state_t; struct evbuffer; struct protocol_t; +struct protocol_params_t; -#define SHARED_SECRET_LENGTH 16 +#define SHA256_LENGTH 32 +#define SHARED_SECRET_LENGTH SHA256_LENGTH int obfs2_init(void); -void *obfs2_new(struct protocol_t *proto_struct, int initiator, const char *parameters); +void *obfs2_new(struct protocol_t *proto_struct, + struct protocol_params_t *params); #ifdef CRYPT_PROTOCOL_PRIVATE

1 0

[obfsproxy/master] Small fix.
by nickm＠torproject.org 29 May '11

29 May '11

commit 5eafc3f2382b5c7ee5115005b887dbe51695fd23 Author: George Kadianakis <desnacked(a)gmail.com> Date: Tue May 17 23:33:42 2011 +0200 Small fix. --- src/protocols/obfs2.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index aba8ea9..fe50553 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -153,7 +153,8 @@ obfs2_state_new(int initiator, const char *shared_secret) } if (shared_secret) - obfs2_state_set_shared_secret(state, shared_secret); + if (obfs2_state_set_shared_secret(state, shared_secret)<0) + return NULL; /* Derive the key for what we're sending */ state->send_padding_crypto = derive_padding_key(state, seed, send_pad_type);

1 0

[obfsproxy/master] Killed some magic numbers and replaced them with SHA256_LENGTH.
by nickm＠torproject.org 29 May '11

29 May '11

commit 4f55412fbf663977faf26847f6425ce5e4ea2f7b Author: George Kadianakis <desnacked(a)gmail.com> Date: Tue May 24 23:52:10 2011 +0200 Killed some magic numbers and replaced them with SHA256_LENGTH. --- src/protocols/obfs2.c | 4 ++-- src/protocols/obfs2.h | 1 - src/protocols/obfs2_crypt.c | 4 ++-- src/protocols/obfs2_crypt.h | 2 ++ 4 files changed, 6 insertions(+), 5 deletions(-) diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index 1377dfe..3490d0e 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -74,7 +74,7 @@ derive_key(void *s, const char *keytype) obfs2_state_t *state = s; crypt_t *cryptstate; - uchar buf[32]; + uchar buf[SHA256_LENGTH]; digest_t *c = digest_new(); digest_update(c, (uchar*)keytype, strlen(keytype)); if (seed_nonzero(state->initiator_seed)) @@ -99,7 +99,7 @@ derive_padding_key(void *s, const uchar *seed, obfs2_state_t *state = s; crypt_t *cryptstate; - uchar buf[32]; + uchar buf[SHA256_LENGTH]; digest_t *c = digest_new(); digest_update(c, (uchar*)keytype, strlen(keytype)); if (seed_nonzero(seed)) diff --git a/src/protocols/obfs2.h b/src/protocols/obfs2.h index bc8a22d..1f9f31d 100644 --- a/src/protocols/obfs2.h +++ b/src/protocols/obfs2.h @@ -15,7 +15,6 @@ struct evbuffer; struct protocol_t; struct protocol_params_t; -#define SHA256_LENGTH 32 #define SHARED_SECRET_LENGTH SHA256_LENGTH int obfs2_init(void); diff --git a/src/protocols/obfs2_crypt.c b/src/protocols/obfs2_crypt.c index 0121c93..50d094c 100644 --- a/src/protocols/obfs2_crypt.c +++ b/src/protocols/obfs2_crypt.c @@ -109,7 +109,7 @@ digest_update(digest_t *d, const uchar *buf, size_t len) size_t digest_getdigest(digest_t *d, uchar *buf, size_t len) { - uchar tmp[32]; + uchar tmp[SHA256_LENGTH]; int n = 32; SHA256_Final(tmp, &d->ctx); if (len < 32) @@ -137,7 +137,7 @@ digest_update(digest_t *d, const uchar *buf, size_t len) size_t digest_getdigest(digest_t *d, uchar *buf, size_t len) { - uchar tmp[32]; + uchar tmp[SHA256_LENGTH]; int n = 32; sha256_done(&d->ctx, tmp); if (len < 32) diff --git a/src/protocols/obfs2_crypt.h b/src/protocols/obfs2_crypt.h index c9841d8..ef279e9 100644 --- a/src/protocols/obfs2_crypt.h +++ b/src/protocols/obfs2_crypt.h @@ -10,6 +10,8 @@ #include <sys/types.h> +#define SHA256_LENGTH 32 + /* Stream cipher state */ typedef struct crypt_t crypt_t; /* Digest state */

1 0

[obfsproxy/master] Trivial improvements over the code:
by nickm＠torproject.org 29 May '11

29 May '11

commit 75ecf16d8342a34357ef39b3fe339590097896fd Author: George Kadianakis <desnacked(a)gmail.com> Date: Tue May 24 22:32:47 2011 +0200 Trivial improvements over the code: * typedef'ed protocol_params_t * we now also free() the protocol_params_t itself in protocol_params_free(). --- src/network.c | 7 ++++--- src/protocol.c | 2 +- src/protocol.h | 10 +++++----- src/protocols/dummy.c | 2 +- src/protocols/obfs2.c | 8 ++++---- 5 files changed, 15 insertions(+), 14 deletions(-) diff --git a/src/network.c b/src/network.c index 07efbc4..a2dc410 100644 --- a/src/network.c +++ b/src/network.c @@ -29,7 +29,7 @@ struct listener_t { int target_address_len; int mode; int proto; /* Protocol that this listener can speak. */ - struct protocol_params_t *proto_params; + protocol_params_t *proto_params; }; static void simple_listener_cb(struct evconnlistener *evcl, @@ -68,7 +68,7 @@ listener_new(struct event_base *base, lsn->proto = protocol; lsn->mode = mode; - struct protocol_params_t *proto_params = calloc(1, sizeof(struct protocol_params_t)); + protocol_params_t *proto_params = calloc(1, sizeof(protocol_params_t)); proto_params->is_initiator = mode != LSN_SIMPLE_SERVER; proto_params->shared_secret = shared_secret; proto_params->shared_secret_len = shared_secret_len; @@ -97,11 +97,12 @@ listener_new(struct event_base *base, } static void -protocol_params_free(struct protocol_params_t *params) +protocol_params_free(protocol_params_t *params) { assert(params); if (params->shared_secret) free(&params->shared_secret); + free(params); } void diff --git a/src/protocol.c b/src/protocol.c index 4e6ae81..8fff6a3 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -31,7 +31,7 @@ set_up_protocol(int protocol) { Return the protocol_t if successful, NULL otherwise. */ struct protocol_t * -proto_new(int protocol, struct protocol_params_t *params) { +proto_new(int protocol, protocol_params_t *params) { struct protocol_t *proto = calloc(1, sizeof(struct protocol_t)); if (!proto) return NULL; diff --git a/src/protocol.h b/src/protocol.h index 6b609ee..e4c3e0f 100644 --- a/src/protocol.h +++ b/src/protocol.h @@ -13,12 +13,12 @@ struct evbuffer; be inherited by *all* connections opened from the listener_t that owns this protocol_params_t. */ -struct protocol_params_t { -int is_initiator; +typedef struct protocol_params_t { + int is_initiator; const char *shared_secret; size_t shared_secret_len; -}; +} protocol_params_t; struct protocol_t { /* protocol */ @@ -49,7 +49,7 @@ typedef struct protocol_vtable { /* Constructor: Creates a protocol object. */ void *(*create)(struct protocol_t *proto_struct, - struct protocol_params_t *parameters); + protocol_params_t *parameters); /* does handshake. Not all protocols have a handshake. */ int (*handshake)(void *state, @@ -69,7 +69,7 @@ typedef struct protocol_vtable { int set_up_protocol(int protocol); struct protocol_t *proto_new(int protocol, - struct protocol_params_t *params); + protocol_params_t *params); void proto_destroy(struct protocol_t *proto); int proto_handshake(struct protocol_t *proto, void *buf); int proto_send(struct protocol_t *proto, void *source, void *dest); diff --git a/src/protocols/dummy.c b/src/protocols/dummy.c index 79d40e0..482c927 100644 --- a/src/protocols/dummy.c +++ b/src/protocols/dummy.c @@ -37,7 +37,7 @@ dummy_init(void) { void * dummy_new(struct protocol_t *proto_struct, - struct protocol_params_t *params) + protocol_params_t *params) { proto_struct->vtable = vtable; diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index 277ca63..1377dfe 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -26,7 +26,7 @@ static int obfs2_send(void *state, struct evbuffer *source, struct evbuffer *dest); static int obfs2_recv(void *state, struct evbuffer *source, struct evbuffer *dest); -static void *obfs2_state_new(struct protocol_params_t *params); +static void *obfs2_state_new(protocol_params_t *params); static int obfs2_state_set_shared_secret(void *s, const char *secret, size_t secretlen); @@ -117,7 +117,7 @@ derive_padding_key(void *s, const uchar *seed, void * obfs2_new(struct protocol_t *proto_struct, - struct protocol_params_t *params) + protocol_params_t *params) { assert(vtable); proto_struct->vtable = vtable; @@ -131,7 +131,7 @@ obfs2_new(struct protocol_t *proto_struct, NULL on failure. */ static void * -obfs2_state_new(struct protocol_params_t *params) +obfs2_state_new(protocol_params_t *params) { obfs2_state_t *state = calloc(1, sizeof(obfs2_state_t)); uchar *seed; @@ -183,9 +183,9 @@ obfs2_state_set_shared_secret(void *s, const char *secret, obfs2_state_t *state = s; digest_t *c = digest_new(); - /* ASN do we like this cast here? */ digest_update(c, (uchar*)secret, secretlen); digest_getdigest(c, buf, sizeof(buf)); + memcpy(state->secret_seed, buf, SHARED_SECRET_LENGTH); memset(buf,0,SHARED_SECRET_LENGTH);

1 0

[obfsproxy/master] Added a warning in obfs2_recv() since we are sending pending data on
by nickm＠torproject.org 29 May '11

29 May '11

commit ad09a5176ed9a7d171ffe7a98ef36801767b08db Author: George Kadianakis <desnacked(a)gmail.com> Date: Thu May 26 00:36:50 2011 +0200 Added a warning in obfs2_recv() since we are sending pending data on the next obfs2_send() instead of sending them at the moment init_crypto() is done. --- src/protocols/obfs2.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index b3fe590..a8f9155 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -398,6 +398,10 @@ obfs2_recv(void *s, struct evbuffer *source, if (plength > OBFUSCATE_MAX_PADDING) return -1; + /* XXX FIXME we should now be sending any 'pending_data_to_send' + but we can't send them from here, so we send them with + obfs2_send() when we next have to send data */ + /* Now we're waiting for plength bytes of padding */ state->padding_left_to_read = plength; state->state = ST_WAIT_FOR_PADDING;

1 0

[obfsproxy/master] Fixed stupid bug.
by nickm＠torproject.org 29 May '11

29 May '11

commit 35abc50a3646d6165ba7f3e9ac0efd218bb0e162 Author: George Kadianakis <desnacked(a)gmail.com> Date: Wed May 25 04:51:51 2011 +0200 Fixed stupid bug. --- src/protocols/obfs2.c | 16 ++++++++-------- 1 files changed, 8 insertions(+), 8 deletions(-) diff --git a/src/protocols/obfs2.c b/src/protocols/obfs2.c index 6221bb2..4159691 100644 --- a/src/protocols/obfs2.c +++ b/src/protocols/obfs2.c @@ -290,13 +290,20 @@ obfs2_send(void *s, obfs2_state_t *state = s; if (state->send_crypto) { + /* First of all, send any data that we've been waiting to send. */ + if (state->pending_data_to_send) { + crypt_and_transmit(state->send_crypto, state->pending_data_to_send, dest); + evbuffer_free(state->pending_data_to_send); + state->pending_data_to_send = NULL; + } /* Our crypto is set up; just relay the bytes */ return crypt_and_transmit(state->send_crypto, source, dest); } else { /* Our crypto isn't set up yet, we'll have to queue the data */ if (evbuffer_get_length(source)) { if (! state->pending_data_to_send) { - state->pending_data_to_send = evbuffer_new(); + if ((state->pending_data_to_send = evbuffer_new()) == NULL) + return -1; } evbuffer_add_buffer(state->pending_data_to_send, source); } @@ -387,13 +394,6 @@ obfs2_recv(void *s, struct evbuffer *source, if (plength > OBFUSCATE_MAX_PADDING) return -1; - /* Send any data that we've been waiting to send */ - if (state->pending_data_to_send) { - crypt_and_transmit(state->send_crypto, state->pending_data_to_send, dest); - evbuffer_free(state->pending_data_to_send); - state->pending_data_to_send = NULL; - } - /* Now we're waiting for plength bytes of padding */ state->padding_left_to_read = plength; state->state = ST_WAIT_FOR_PADDING;

1 0

[obfsproxy/master] Revived unit tests.
by nickm＠torproject.org 29 May '11

29 May '11

commit 9d2e98860ed5c0e5f6a6a45869a20732a0a01218 Author: George Kadianakis <desnacked(a)gmail.com> Date: Wed May 25 04:10:23 2011 +0200 Revived unit tests. --- src/test/unittest.c | 2 +- src/test/unittest_obfs2.c | 99 ++++++++++++++++++++++++++++++++++++++------ 2 files changed, 86 insertions(+), 15 deletions(-) diff --git a/src/test/unittest.c b/src/test/unittest.c index 9ca6a74..41159ca 100644 --- a/src/test/unittest.c +++ b/src/test/unittest.c @@ -15,7 +15,7 @@ extern struct testcase_t socks_tests[]; struct testgroup_t groups[] = { { "crypt/", crypt_tests }, - /* { "proto/", protocol_tests }, */ + { "proto/", protocol_tests }, { "socks/", socks_tests }, END_OF_GROUPS }; diff --git a/src/test/unittest_obfs2.c b/src/test/unittest_obfs2.c index ce743c8..052c909 100644 --- a/src/test/unittest_obfs2.c +++ b/src/test/unittest_obfs2.c @@ -1,4 +1,3 @@ -#if 0 /* Copyright 2011 Nick Mathewson You may do anything with this work that copyright law would normally @@ -32,8 +31,20 @@ test_proto_setup(void *data) tt_assert(set_up_protocol(OBFS2_PROTOCOL) >= 0); - client_proto = proto_new(OBFS2_PROTOCOL,1); - server_proto = proto_new(OBFS2_PROTOCOL,1); + protocol_params_t *proto_params_serv = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_serv); + proto_params_serv->is_initiator = 1; + proto_params_serv->shared_secret = "hahaha"; + proto_params_serv->shared_secret_len = 7; + + protocol_params_t *proto_params_client = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_client); + proto_params_client->is_initiator = 0; + proto_params_client->shared_secret = "hahaha"; + proto_params_client->shared_secret_len = 7; + + client_proto = proto_new(OBFS2_PROTOCOL,proto_params_serv); + server_proto = proto_new(OBFS2_PROTOCOL,proto_params_client); tt_assert(client_proto); tt_assert(server_proto); @@ -61,8 +72,20 @@ test_proto_handshake(void *data) tt_assert(set_up_protocol(OBFS2_PROTOCOL) >= 0); - client_proto = proto_new(OBFS2_PROTOCOL,1); - server_proto = proto_new(OBFS2_PROTOCOL,0); + protocol_params_t *proto_params_serv = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_serv); + proto_params_serv->is_initiator = 1; + proto_params_serv->shared_secret = "hahaha"; + proto_params_serv->shared_secret_len = 7; + + protocol_params_t *proto_params_client = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_client); + proto_params_client->is_initiator = 0; + proto_params_client->shared_secret = "hahaha"; + proto_params_client->shared_secret_len = 7; + + client_proto = proto_new(OBFS2_PROTOCOL,proto_params_serv); + server_proto = proto_new(OBFS2_PROTOCOL,proto_params_client); tt_assert(client_proto); tt_assert(server_proto); @@ -121,8 +144,20 @@ test_proto_transfer(void *data) tt_assert(set_up_protocol(OBFS2_PROTOCOL) >= 0); - client_proto = proto_new(OBFS2_PROTOCOL,1); - server_proto = proto_new(OBFS2_PROTOCOL,0); + protocol_params_t *proto_params_serv = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_serv); + proto_params_serv->is_initiator = 1; + proto_params_serv->shared_secret = "hahaha"; + proto_params_serv->shared_secret_len = 7; + + protocol_params_t *proto_params_client = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_client); + proto_params_client->is_initiator = 0; + proto_params_client->shared_secret = "hahaha"; + proto_params_client->shared_secret_len = 7; + + client_proto = proto_new(OBFS2_PROTOCOL,proto_params_serv); + server_proto = proto_new(OBFS2_PROTOCOL,proto_params_client); tt_assert(client_proto); tt_assert(server_proto); @@ -204,9 +239,21 @@ test_proto_splitted_handshake(void *data) struct protocol_t *server_proto = NULL; tt_assert(set_up_protocol(OBFS2_PROTOCOL) >= 0); + + protocol_params_t *proto_params_serv = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_serv); + proto_params_serv->is_initiator = 1; + proto_params_serv->shared_secret = "hahaha"; + proto_params_serv->shared_secret_len = 7; - client_proto = proto_new(OBFS2_PROTOCOL,1); - server_proto = proto_new(OBFS2_PROTOCOL,0); + protocol_params_t *proto_params_client = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_client); + proto_params_client->is_initiator = 0; + proto_params_client->shared_secret = "hahaha"; + proto_params_client->shared_secret_len = 7; + + client_proto = proto_new(OBFS2_PROTOCOL,proto_params_serv); + server_proto = proto_new(OBFS2_PROTOCOL,proto_params_client); tt_assert(client_proto); tt_assert(server_proto); @@ -346,8 +393,20 @@ test_proto_wrong_handshake_magic(void *data) tt_assert(set_up_protocol(OBFS2_PROTOCOL) >= 0); - client_proto = proto_new(OBFS2_PROTOCOL,1); - server_proto = proto_new(OBFS2_PROTOCOL,0); + protocol_params_t *proto_params_serv = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_serv); + proto_params_serv->is_initiator = 1; + proto_params_serv->shared_secret = "hahaha"; + proto_params_serv->shared_secret_len = 7; + + protocol_params_t *proto_params_client = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_client); + proto_params_client->is_initiator = 0; + proto_params_client->shared_secret = "hahaha"; + proto_params_client->shared_secret_len = 7; + + client_proto = proto_new(OBFS2_PROTOCOL,proto_params_serv); + server_proto = proto_new(OBFS2_PROTOCOL,proto_params_client); tt_assert(client_proto); tt_assert(server_proto); @@ -413,8 +472,21 @@ test_proto_wrong_handshake_plength(void *data) tt_assert(set_up_protocol(OBFS2_PROTOCOL) >= 0); - client_proto = proto_new(OBFS2_PROTOCOL,1); - server_proto = proto_new(OBFS2_PROTOCOL,0); + protocol_params_t *proto_params_serv = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_serv); + proto_params_serv->is_initiator = 1; + proto_params_serv->shared_secret = "hahaha"; + proto_params_serv->shared_secret_len = 7; + + protocol_params_t *proto_params_client = calloc(1, sizeof(protocol_params_t)); + tt_assert(proto_params_client); + proto_params_client->is_initiator = 0; + proto_params_client->shared_secret = "hahaha"; + proto_params_client->shared_secret_len = 7; + + + client_proto = proto_new(OBFS2_PROTOCOL,proto_params_serv); + server_proto = proto_new(OBFS2_PROTOCOL,proto_params_client); tt_assert(client_proto); tt_assert(server_proto); @@ -475,4 +547,3 @@ struct testcase_t protocol_tests[] = { T(wrong_handshake_plength, 0), END_OF_TESTCASES }; -#endif

1 0

[obfsproxy/master] Merge remote-tracking branch 'asn/shared_secret'
by nickm＠torproject.org 29 May '11

29 May '11

commit 9ef190a4d70cd44053dde4d19d5579a609ced091 Merge: 8ac51f3 ad09a51 Author: Nick Mathewson <nickm(a)torproject.org> Date: Sat May 28 21:34:22 2011 -0400 Merge remote-tracking branch 'asn/shared_secret' Conflicts: doc/protocol-spec.txt doc/protocol-spec.txt | 12 ++++-- src/main.c | 38 ++++++++++------- src/network.c | 43 +++++++++++-------- src/protocol.c | 6 +- src/protocol.h | 59 ++++++++++++++++++-------- src/protocols/dummy.c | 6 +- src/protocols/dummy.h | 3 +- src/protocols/obfs2.c | 94 +++++++++++++++++++++++++++++++---------- src/protocols/obfs2.h | 9 ++-- src/protocols/obfs2_crypt.c | 4 +- src/protocols/obfs2_crypt.h | 2 + src/test/unittest_obfs2.c | 97 +++++++++++++++++++++++++++++++++++++----- 12 files changed, 272 insertions(+), 101 deletions(-) diff --cc doc/protocol-spec.txt index 471f2c0,798da14..c11f653 --- a/doc/protocol-spec.txt +++ b/doc/protocol-spec.txt @@@ -16,13 -16,15 +16,15 @@@ The Twobfuscato 1. Primitives, notation, and constants. - H(x) is SHA256 of X + H(x) is SHA256 of x. + H^n(x) is H(x) called iteratively n times. + - E_K(s) is the AES-counter-mode encryption of s using the key K. + E_K(s) is the AES-CTR-128 encryption of s using K as key. - x | y is the concatenation of x and y - UINT32(n) is the 4 byte value of n in big-endian (network) order - SR(n) is n bytes of strong random data - WR(n) is n bytes of weaker random data + x | y is the concatenation of x and y. + UINT32(n) is the 4 byte value of n in big-endian (network) order. + SR(n) is n bytes of strong random data. + WR(n) is n bytes of weaker random data. "xyz" is the ASCII characters 'x', 'y', and 'z', not NUL-terminated. s[:n] is the first n bytes of s. s[n:] is the last n bytes of s.

1 0