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What little-t-tor bridge features/issues we should address?
by George Kadianakis 14 Jul '14

14 Jul '14

Hello Roger and Nick, as far as I know, bridge support was hastily implemented in little-t-tor, and it does not support all the features we would like it to support. During the dev meeting roadmapping, we added a task about improving the bridge implementation in Tor. Some of the items in the task are: - Bridges should save bridge information to the state file (proposal 192) - Fix UpdateBridgesFromAuthority. - Obfsbridges should be able to hide their ORPort (#7349) Some of those items are more long-term than others. What other tasks would you like to see in there? We are looking for tasks mainly related to bridges themselves, and not PTs. Thanks!

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Re: [tor-dev] :(
by vmon＠riseup.net 14 Jul '14

14 Jul '14

Interesting! It is not a fundamental error per say, if you are a server you can't handle more than some number of connections anyway (you can increase that if you are root), so the client need to wait. You need a ddos defence mechanism against that (e.g. iptables) independent of what kind of server you are running. However, I put a defence mechanism against a ST client being able to open too many connections on the client side barring it by this formula: min(8, and ceilling of (MAX - count)/no of circ) I wonder how does it get bypassed : chop.cc:722 // If we're the client and we had no target connection, try // reopening new connections. If we're the server, we have to // just twiddle our thumbs and hope the client does that. if (no_target_connection) { log_debug(this, "number of open connections on this circuit %u, golobally %u", (unsigned int)downstreams.size(), (unsigned int) conn_count()); if (config->mode != LSN_SIMPLE_SERVER && (int)downstreams.size() < min(MAX_CONN_PER_CIRCUIT, ((int)(MAX_GLOBAL_CONN_COUNT - conn_count() + (int)circuit_count() - 1)/(int)circuit_count()))) //min(8, and ceilling of (MAX - count)/no of circ) circuit_reopen_downstreams(this); If you start many ST clients though that won't be effective and you are basically ddosing the server. vmon Noah Rahman <selimthegrim(a)gmail.com> writes: > 7477.6308 [debug] http_server_JS_transmit: SERVER found the applicable > HTTP response template with size 10399 > 7477.6324 [debug] conn_do_flush: <1102.35442> flushing 6349 bytes to > peer [enabled=6] > 7477.6324 [debug] send_targeted: <1102.35442> transmitted block 4 > <d=488 p=3 f=DAT> > T:7477.6324: ckt 1102 <ntp 5 outq 0>: send 4 <d=488 p=3 f=DAT> > 7477.6324 [debug] send_targeted: <1102> efficiency: 24.813380 > 7477.6325 [debug] downstream_flush_cb: <1102.35442> 0 bytes still to > transmit (reached EOF) (received EOF) > 7477.6326 [debug] drop_downstream: <1102> dropped connection > <1102.35442> to 127.0.0.1:51874, now 0 > 7477.6326 [debug] circuit_arm_axe_timer: <1102> axe after 1800000 > milliseconds > 7477.6326 [debug] close: <0.35442> closing connection; 736 remaining > 7477.6326 [debug] close_cleanup_cb: cleaning up 0 circuits and 1 > connections > 7477.6380 [info] server_listener_cb: 127.0.0.1:5000: new connection to > server from 127.0.0.1:51875 > 7477.6381 [debug] conn_create: <0.35443> new connection > 7477.6381 [debug] downstream_flush_cb: <0.35443> 0 bytes still to > transmit (no circuit) (never received) > 7477.6387 [debug] downstream_read_cb: <0.35443> 836 bytes available > 7477.6387 [debug] http_server_receive: <0.35443> SERVER received > request header of length 832 > 7477.6388 [debug] http_server_receive: Cookie: > 1o9Pt2B-kM=37XmMDPvsABcxKIT2I5nqNQOkkUKqhR7sAAAAFAT4AAAEAAAAAAAAAFgMBAQYQAAECAQAhhD7ExjZhmIiu2IaFGdGrT1arN52cDxVTXFe07egCZNbiKmf6yS9s9hRlJ489X2wZ5S7c00ORL9GU907NN3DqOG9EtcichBTz3V6MdLVVNxrCqWwMOiJIbCZ277f2pO; > F=QJ3or_CLfT-VVLEGeopox1nLiFoPjpMXXWmFMHl9OW4GQ49L5Z5Y8KNph2d8mQ3ViIjMzMPctvOzUoxcBhx2er_ > VIPfhqAh3s;ybTJK4VpoL=cH_avl8ZEIiw3Q_WZdqvCPF6EE;3Bqa=OFSbR36AqM3s7pr2N2e9Fv_ > IoJSQUvmnySI6bBC1VpTKXzv2hJ2W6P1hdRtxQrJmWWukBcWsKLUwFAMBAAEBFgMBACiF_LOpLxeA7Y1c; > n-5Sytb5R=2sQrFg4MK8c;Xz_=Z_ALz5YDp938ckzYjAAAAAA;AAAAAAA=AAAAAAAAA.. > > 7477.6389 [debug] transmit_soon: <0.35443> must send within 100 > milliseconds > 7477.6389 [debug] verify_and_extract: retrieved circ id 3075444694 > 7477.6389 [debug] recv_handshake: <0.35443> found circuit to > 127.0.0.1:5001 > 7477.6389 [debug] add_downstream: <1102> added connection <1102.35443> > to 127.0.0.1:51875, now 1 > 7477.6390 [debug] recv: <1102.35443> circuit to 127.0.0.1:5001 > 7477.6390 [debug] recv: <1102.35443> 350 bytes available > 7477.6390 [debug] recv: <1102.35443> receiving block 5 <d=318 p=0 > f=DAT r=0> > T:7477.6390: ckt 1102 <ntp 5 outq 0>: recv 5 <d=318 p=0 f=DAT r=0> > 7477.6391 [debug] recv: Data received: > 7477.6391 [debug] remove_next: next_to_process=5 data=0xe140740 op=DAT > 7477.6391 [debug] remove_next: next_to_process=6 data=(nil) op=XXX > 7477.6391 [debug] process_queue: <1102> processed 1 blocks > 7477.6392 [debug] upstream_flush_cb: <1102> 0 bytes still to transmit > 7477.6850 [debug] upstream_read_cb: <1102> 51 bytes available > 7477.6851 [debug] send: <1102> 51 bytes to send > 7477.6851 [debug] pick_connection: <1102> target block size 83 bytes > 7477.6851 [debug] pick_connection: <1102.35443> has been connected for > 0 secs > 7477.6851 [debug] transmit_room: <1102.35443> checking available > capacity for type 3 > 7477.6852 [debug] pick_connection: <1102.35443> offers 115 bytes > (http) > 7477.6852 [debug] pick_connection: <1102> no req: 9 avg des: > 712.111111 avg act: 663.333333 > 7477.6852 [debug] pick_connection: <1102> minabove 115 for > <1102.35443> maxbelow 0 for <1102.0> > 7477.6853 [debug] get_payload: contentType = 3, initTypePayload = 1, > typePayloadCount = 613 > 7477.6853 [debug] get_payload: first payload size=9647, best payload > size=3162, num candidate=100 > > 7477.6853 [debug] pick_appropriate_cover_payload: SERVER found the > next HTTP response template with size 3162 > 7477.6854 [debug] http_server_transmit: coping body of 3014 size > 7477.6854 [debug] http_server_transmit: SERVER embeding data1 with > length 83 into type 3 > 7477.6857 [debug] http_server_transmit: SERVER FileSteg sends resp > with hdr len 148 body len 106 > 7477.6858 [debug] conn_do_flush: <1102.35443> flushing 3309 bytes to > peer [enabled=6] > 7477.6858 [debug] send_targeted: <1102.35443> transmitted block 5 > <d=51 p=0 f=DAT> > T:7477.6858: ckt 1102 <ntp 6 outq 0>: send 5 <d=51 p=0 f=DAT> > 7477.6858 [debug] send_targeted: <1102> efficiency: 24.809808 > 7477.6859 [debug] downstream_flush_cb: <1102.35443> 0 bytes still to > transmit (reached EOF) (received EOF) > 7477.6860 [debug] drop_downstream: <1102> dropped connection > <1102.35443> to 127.0.0.1:51875, now 0 > 7477.6860 [debug] circuit_arm_axe_timer: <1102> axe after 1800000 > milliseconds > 7477.6860 [debug] close: <0.35443> closing connection; 736 remaining > 7477.6860 [debug] close_cleanup_cb: cleaning up 0 circuits and 1 > connections > 7477.7882 [info] server_listener_cb: 127.0.0.1:5000: new connection to > server from 127.0.0.1:51876 > 7477.7882 [debug] conn_create: <0.35444> new connection > 7477.7883 [debug] downstream_flush_cb: <0.35444> 0 bytes still to > transmit (no circuit) (never received) > 7477.7890 [debug] downstream_read_cb: <0.35444> 425 bytes available > 7477.7891 [debug] http_server_receive: <0.35444> SERVER received > request header of length 421 > 7477.7891 [debug] http_server_receive: Cookie: > 1o9Pt0=f_eWs3tuUJLpu8g2aiE1m2BwMF6jib99twQLIAAAAGAAAAAQEAAAAA;AAAAAAAAA=A; > AAAAAAAAA=AAAAAAAA. > > 7477.7891 [debug] transmit_soon: <0.35444> must send within 100 > milliseconds > 7477.7892 [debug] verify_and_extract: retrieved circ id 3075444694 > 7477.7892 [debug] recv_handshake: <0.35444> found circuit to > 127.0.0.1:5001 > 7477.7892 [debug] add_downstream: <1102> added connection <1102.35444> > to 127.0.0.1:51876, now 1 > 7477.7892 [debug] recv: <1102.35444> circuit to 127.0.0.1:5001 > 7477.7893 [debug] recv: <1102.35444> 33 bytes available > 7477.7893 [debug] recv: <1102.35444> receiving block 6 <d=0 p=1 f=DAT > r=0> > T:7477.7893: ckt 1102 <ntp 6 outq 0>: recv 6 <d=0 p=1 f=DAT r=0> > 7477.7893 [debug] remove_next: next_to_process=6 data=0xe1683d0 op=DAT > 7477.7893 [debug] remove_next: next_to_process=7 data=(nil) op=XXX > 7477.7894 [debug] process_queue: <1102> processed 1 blocks > lliseconds > 7477.8125 [debug] verify_and_extract: retrieved circ id 4060828808 > 7477.8125 [debug] circuit_create: <1103> new circuit > 7477.8125 [info] circuit_open_upstream: <1103> trying to connect to > 127.0.0.1:5001 > 7477.8126 [info] circuit_open_upstream: <1103> connection to > 127.0.0.1:5001 failed: Too many open files7477.8047 [info] > server_listener_cb: 127.0.0.1:5000: new connection to server from > 127.0.0.1:51877 > 7477.8048 [debug] conn_create: <0.35445> new connection > [warn] Error from accept() call: Too many open files > 7477.8048 [debug] downstream_flush_cb: <0.35445> 0 bytes still to > transmit (no circuit) (never received) > 7477.8054 [debug] downstream_read_cb: <0.35445> 506 bytes available > 7477.8054 [debug] http_server_receive: <0.35445> SERVER received > request header of length 502 > 7477.8054 [debug] http_server_receive: Cookie: > 1o9=Pt6QwYewJ9F6kjH;fGyxKq9Ti=cPKqah0wQFhNNL-wAAAAHAB0ABwEAAAAA;AA=AAFQMBABjR- > 87YPxS9nJMDyQOhg3303;SW3kO=0Q03gAAAAAAA;AAA=AAAAAAAA;AAAAAA=AAAA;AAA=.. > > 7477.8055 [debug] transmit_soon: <0.35445> must send within 100 > milliseconds > 7477.8055 [debug] verify_and_extract: retrieved circ id 3075444694 > 7477.8055 [debug] recv_handshake: <0.35445> found circuit to > 127.0.0.1:5001 > 7477.8056 [debug] add_downstream: <1102> added connection <1102.35445> > to 127.0.0.1:51877, now 2 > 7477.8056 [debug] recv: <1102.35445> circuit to 127.0.0.1:5001 > 7477.8056 [debug] recv: <1102.35445> 68 bytes available > 7477.8056 [debug] recv: <1102.35445> receiving block 7 <d=29 p=7 f=DAT > r=0> > T:7477.8057: ckt 1102 <ntp 7 outq 0>: recv 7 <d=29 p=7 f=DAT r=0> > 7477.8057 [debug] recv: Data received: > 7477.8057 [debug] remove_next: next_to_process=7 data=0xe1683d0 op=DAT > 7477.8057 [debug] remove_next: next_to_process=8 data=(nil) op=XXX > 7477.8058 [debug] process_queue: <1102> processed 1 blocks > 7477.8058 [debug] upstream_flush_cb: <1102> 0 bytes still to transmit > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > 7477.8095 [info] upstream_event_cb: <1102> EOF from upstream > 7477.8095 [debug] send: <1102> 0 bytes to send > 7477.8095 [debug] pick_connection: <1102> target block size 32 bytes > 7477.8095 [debug] pick_connection: <1102.35444> has been connected for > 0 secs > 7477.8096 [debug] transmit_room: <1102.35444> checking available > capacity for type 5 > 7477.8096 [debug] pick_connection: <1102.35444> offers 65 bytes (http) > 7477.8096 [debug] pick_connection: <1102> no req: 10 avg des: > 647.300000 avg act: 603.500000 > 7477.8097 [debug] pick_connection: <1102.35445> has been connected for > 0 secs > 7477.8097 [debug] transmit_room: <1102.35445> checking available > capacity for type 5 > 7477.8097 [debug] pick_connection: <1102.35445> offers 71 bytes (http) > 7477.8097 [debug] pick_connection: <1102> no req: 11 avg des: > 594.272727 avg act: 555.090909 > 7477.8098 [debug] pick_connection: <1102> minabove 65 for <1102.35444> > maxbelow 0 for <1102.0> > 7477.8098 [debug] http_server_JS_transmit: sbuflen = 33 > > 7477.8098 [debug] get_payload: contentType = 5, initTypePayload = 1, > typePayloadCount = 1548 > 7477.8099 [debug] get_payload: first payload size=46676, best payload > size=20041, num candidate=100 > > 7477.8099 [debug] http_server_JS_transmit: SERVER found the applicable > HTTP response template with size 20041 > 7477.8119 [debug] conn_do_flush: <1102.35444> flushing 8060 bytes to > peer [enabled=6] > 7477.8119 [debug] send_targeted: <1102.35444> transmitted block 6 <d=0 > p=1 f=FIN> > T:7477.8119: ckt 1102 <ntp 8 outq 0>: send 6 <d=0 p=1 f=FIN> > 7477.8119 [debug] send_targeted: <1102> efficiency: 24.809808 > 7477.8120 [debug] send: <1102> 1 dead cycles > [warn] Error from accept() call: Too many open files > 7477.8121 [debug] downstream_flush_cb: <1102.35444> 0 bytes still to > transmit (reached EOF) (received EOF) > 7477.8121 [debug] drop_downstream: <1102> dropped connection > <1102.35444> to 127.0.0.1:51876, now 1 > 7477.8121 [debug] close: <0.35444> closing connection; 737 remaining > 7477.8122 [debug] close_cleanup_cb: cleaning up 0 circuits and 1 > connections > 7477.8123 [info] server_listener_cb: 127.0.0.1:5000: new connection to > server from 127.0.0.1:51879 > 7477.8123 [debug] conn_create: <0.35446> new connection > [warn] Error from accept() call: Too many open files > [warn] Error from accept() call: Too many open files > 7477.8124 [debug] downstream_read_cb: <0.35446> 443 bytes available > 7477.8124 [debug] http_server_receive: <0.35446> SERVER received > request header of length 439 > 7477.8124 [debug] http_server_receive: Cookie: > iFQ=L8srwNz_kQgBW4weYMYT;sLEmEhA8VZ=9NBYIXNQa0AAAAAAAAA;A=AEAAAAAA;A=AA; > AAAAAAAAAA=AAAAA;AAA=AAAA.. > > 7477.8125 [debug] transmit_soon: <0.35446> must send within 100 mi

2 1

[patch] properly test for OPENSSL_NO_COMP
by Pascal Stumpf 14 Jul '14

14 Jul '14

LibreSSL has removed compression support. Tor should check for the OPENSSL_NO_COMP define before trying to disable compression at runtime. diff --git a/src/common/tortls.c b/src/common/tortls.c index e06a2ae..0f98968 100644 --- a/src/common/tortls.c +++ b/src/common/tortls.c @@ -1314,10 +1314,12 @@ tor_tls_context_new(crypto_pk_t *identity, unsigned int key_lifetime, SSL_CTX_set_options(result->ctx, SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION); } +#ifndef OPENSSL_NO_COMP /* Don't actually allow compression; it uses ram and time, but the data * we transmit is all encrypted anyway. */ if (result->ctx->comp_methods) result->ctx->comp_methods = NULL; +#endif #ifdef SSL_MODE_RELEASE_BUFFERS SSL_CTX_set_mode(result->ctx, SSL_MODE_RELEASE_BUFFERS); #endif

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Re: [tor-dev] Using ScrambleSuit with something other than Tor
by Philipp Winter 11 Jul '14

11 Jul '14

Hi Yuhao, On Fri, Jul 11, 2014 at 08:20:25PM +0800, Yuhao Dong wrote: > I'm Yuhao Dong (undergrad student at University of Waterloo) and I'm > currently doing research on, surprise, my own traffic obfuscation > system. Cool! I'm in Toronto until the middle of August -- in case you are back until then and want to meet up in person. > I'd like to compare it to ScrambleSuit; however I am > currently on break in China. It is going to be really hard to set up > Tor in a way that works; besides, I am using a test suite that > transmits specially-shaped traffic over HTTP. I would like to be > able to see what happens if I apply ScrambleSuit to that traffic > instead of Tor. That sounds good. Given Tor's high variance in latency and throughput, it's more effective to compare the performance of pluggable transports without Tor, in a LAN setting. > Is there a way to build a generic ScrambleSuit SOCKS5 proxy? In > other words, it would be awesome if I could set up two servers on my > LAN: > > web browsing client <-SOCKS-> first LAN server <-ScrambleSuit-> > second LAN server <-> Internet > > so that arbitrary traffic can be tunneled through ScrambleSuit, and > I can do packet analysis on the ScrambleSuit link. > > I understand that Tor's "pluggable transport" system uses SOCKS5 > underneath; however the spec seems very vague on how to precisely > get that local SOCKS5 address. How can I use ScrambleSuit in the way > I described, to encapsulate something other than Tor? It sounds like you basically want to have obfsproxy with ScrambleSuit on both your LAN servers. The first LAN server could be started like this: python /path/to/obfsproxy \ --log-min-severity=debug \ --data-dir=/tmp/scramblesuit-client \ scramblesuit \ --password=BANANASAPPLESCOCONUTSPEACHESEGGS \ --dest SECOND_LAN_SERVER:50000 \ client 0.0.0.0:1080 The second LAN server could be started like this: python /path/to/obfsproxy \ --log-min-severity=debug \ --data-dir=/tmp/scramblesuit-server \ scramblesuit \ --password=BANANASAPPLESCOCONUTSPEACHESEGGS \ --dest SOCKS_PROXY:1234 \ server 0.0.0.0:50000 SOCKS_PROXY can be Tor or an arbitrary SOCKS proxy which allows direct connections to your Internet link. You can then configure arbitrary applications to use the SOCKS5 proxy running on your first LAN server. Hope that helps, Philipp

1 0

SENDME cells
by Gareth Owen 09 Jul '14

09 Jul '14

(sorry re-post - forgot subject) Dear all I'm working on a tor research project and am having difficulty understanding the SENDME cells. The tor spec acknowledges that it isn't particularly clear so I would welcome some clarification please. The spec says that *all* nodes in a circuit maintain a send and receive window, and that this window is decremented on each RELAY_DATA and incremented on each SENDME. Cells that are neither of these do not affect the window size. The problem I have understanding is, that only edge nodes will know whether a cell is a RELAY_DATA, the intermediate nodes only know that its a RELAY but not what type. So, if only RELAY_DATA decrements the window size, and intermediate nodes cannot spot these, what point is there in intermediate nodes having a window? Any help greatly appreciated. Gareth --- Dr Gareth Owen Senior Lecturer School of Computing, University of Portsmouth W: ghowen.me

3 4

(Extra) roadmapping PT meeting this Friday (16:00UTC 11th of July 2014)
by George Kadianakis 08 Jul '14

08 Jul '14

Hello friends, the PT meeting last week was a bit quiet because it was conflicting with the Tor dev meeting. To compensate for that, we are thinking of throwing an extra PT meeting this Friday. The agenda can be modified according to the participants, but we are planning to spend some time writing down the fictional roadmap designed during the dev meeting to a wiki page, so that we can better plan PT development in the months ahead If you are in a roadmapping mood, feel free to pass by and help. As always, the meeting is going to occur at 16:00 UTC. Place is the #tor-dev IRC channel in the OFTC network. Cheers!

1 0

Re: [tor-dev] [HTTPS-Everywhere] [GSoC] HTTPS Everywhere secure ruleset update mechanism update
by Yan Zhu 08 Jul '14

08 Jul '14

(resending to tor-dev with tp.o email address) On 07/08/2014 03:42 AM, Yan Zhu wrote: > On 07/08/2014 12:07 AM, Jeroen Massar wrote: >> On 2014-07-07 20:40, Red wrote: >> [.. lots of cool work being worked on ..] >> >> Hi Zack, >> >> Seems you are doing lots of cool stuff ;) >> >> But I am one of those strange people who really hate it that every >> separate tool has their own updater (which can be used for tracking a >> user, as the set of updater tools polling servers makes a fingerprint in >> the same way other flows make a fingerprint). > > Hi Jeroen, > > This makes a lot of sense. I'm aware of the fingerprintability concern, > and EFF tech projects generally try to mitigate it by polling the update > servers at randomized intervals over fresh Tor circuits if possible. For > this project, we initially proposed polling for an update when the > browser starts and every 3 hours plus some random, evenly-distributed > number of milliseconds between 0 and 300000. I'm curious if others have > more refined suggestions! > >> >> And thus I run Little Snitch and block those updates. Till I deem it a >> good time for the update to be done and trigger it manually. >> >> As such, when you get to the stage of adding features, it would be good >> if there was: >> - an option to disable the auto fetching > > Yes, this would be fairly easy to add. > >> - an option to trigger the fetching > > Probably also easy. > >> - to feed the update mechanism with a pre-fetched file >> (eg provided through a different update mechanism) > > Since the update mechanism is just an XHR that downloads a new ruleset > library from a hardcoded static URL and replaces the existing one in the > Firefox profile directory, you could fetch-and-replace this manually via > any number of mechanisms. :) > > Also, the ruleset libraries will still ship with extension updates, so > you could disable ruleset updates and just wait for the next HTTPS > Everywhere release. > > -Yan > >> >> Greets, >> Jeroen >> >> _______________________________________________ >> tor-dev mailing list >> tor-dev(a)lists.torproject.org >> https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev >> > > > > > _______________________________________________ > HTTPS-Everywhere mailing list > HTTPS-Everywhere(a)lists.eff.org > https://lists.eff.org/mailman/listinfo/https-everywhere > -- Yan Zhu <yan(a)eff.org>, <yan(a)torproject.org> Staff Technologist Electronic Frontier Foundation https://www.eff.org 815 Eddy Street, San Francisco, CA 94109 +1 415 436 9333 x134

2 1

Re: [tor-dev] [HTTPS-Everywhere] [GSoC] HTTPS Everywhere secure ruleset update mechanism update
by Yan Zhu 08 Jul '14

08 Jul '14

(resending to tor-dev with tp.o email address) On 07/08/2014 03:30 AM, Yan Zhu wrote: > On 07/08/2014 02:55 AM, Ben Laurie wrote: >> On 7 July 2014 19:40, Red <redwire(a)riseup.net> wrote: >>> Despite the fact that the process for producing the signature in >>> question[2] seemed to work fine- Openssl was able to generate and verify >>> the signature, the testing code calling the verifyData[3] function used >>> for verification was returning an undocumented NS_ERROR_FAILURE >>> exception. I had spent a great deal of time asking for support in >>> relevant Firefox extension development IRC channels, reading source code >>> from unit tests for the nsIDataSignatureVerifier component, and >>> experimenting with alternative openssl commands in order to try to >>> figure out why this error was occurring. >> >> Looking at the pk1sign source, it looks like the signature needs to be >> in base64. Was that what you were using? >> >> Do you have a test case that fails using command line tools? > > I think Zack's original failing test case was generated via something like: > $ openssl rsautl -sign -in update.digest -out signtmp.sig -inkey privkey.pem > $ openssl base64 -in signtmp.sig -out update.json.sig > > as described in the original spec that we wrote: > https://github.com/redwire/https-everywhere/blob/makeJSONManifest/doc/updat… > > Here is the diff between the failing test and the passing test: > https://github.com/redwire/https-everywhere/commit/8b3c85d9d90d679e8b699701…. > I generated the data for the passing test with pk1sign. > > The documentation for nsIDataSignatureVerifier does not really describe > the expected data format for the signature [1], so it took a while to > figure out that it expects a very specialized form [2]. > > [1] > https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Inter… > [2] https://bugzilla.mozilla.org/show_bug.cgi?id=685852#c0 > > >> _______________________________________________ >> tor-dev mailing list >> tor-dev(a)lists.torproject.org >> https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev >> > > > > > _______________________________________________ > HTTPS-Everywhere mailing list > HTTPS-Everywhere(a)lists.eff.org > https://lists.eff.org/mailman/listinfo/https-everywhere > -- Yan Zhu <yan(a)eff.org>, <yan(a)torproject.org> Staff Technologist Electronic Frontier Foundation https://www.eff.org 815 Eddy Street, San Francisco, CA 94109 +1 415 436 9333 x134

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[GSoC] HTTPS Everywhere secure ruleset update mechanism update
by Red 08 Jul '14

08 Jul '14

Hello everyone, I would like to quickly summarize what has been going on for the last couple of weeks of my work. Due to my mentor, Yan, being away on travel, we haven't had time to have a formal weekly meeting on IRC as per usual. We have, however, been emailing on the HTTPS Everywhere mailing list frequently to discuss some of the problems I've been working on last week. We have also compiled a list of things I am to work on for the next week, which I will summarize here. For the past week, I have been grappling with a problem pertaining to digital signature verification using the nsIDataSignatureVerifier XPCOM component designed to handle this task. I had written a few tests[1] that would use the testing mechanism that Yan built to make sure that the hashing and signature verification my project would rely on for security was working. The testing mechanism was built after our last meeting the Friday before last, during which time we realized we could write a separate Firefox extension using the addon SDK (and thus, Jetpack's testing suite) and import the HTTPS Everywhere component into that extension for testing purposes. Despite the fact that the process for producing the signature in question[2] seemed to work fine- Openssl was able to generate and verify the signature, the testing code calling the verifyData[3] function used for verification was returning an undocumented NS_ERROR_FAILURE exception. I had spent a great deal of time asking for support in relevant Firefox extension development IRC channels, reading source code from unit tests for the nsIDataSignatureVerifier component, and experimenting with alternative openssl commands in order to try to figure out why this error was occurring. Yan was able to get the test to pass by generating a key and signature using the NSS tools. However, she has said that this process is more involved than we would like, and is not likely feasible to accomplish on EFF's airgapped machine hosting its offline private signing key due to the lack of availability of NSS tools. To overcome this limitation, I will be porting one of either the Uhura tool that has been used in the past, or the pk1sign program[4] Yan had found referenced in a Bugzilla report. For now, that's what I'll be doing. I am feeling optimistic that, once this issue of generating an appropriate (i.e. verifiable by nsIDataSignatureVerifier) signature is resolved, writing tests for and refactoring the secure update mechanism I am building will be complete before long. I have compiled some of the discussion Yan and I have had via email into my weekly meeting notes[5], despite there having not been an actual meeting. As usual, I welcome any advice and input! Cheers, Zack [1]: https://github.com/redwire/https-everywhere/blob/feature/tests/https-everyw… [2]: https://github.com/redwire/https-everywhere/blob/rulesetUpdating/doc/update… [3]: https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Inter… [4]: http://dxr.mozilla.org/mozilla-central/source/security/nss/cmd/pk1sign/pk1s… [5]: https://gist.github.com/redwire/b62f03905a826e79947a#week-8

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[PATCH] entrynodes.c: Improve readability (issue 9971)
by Martin Kepplinger 08 Jul '14

08 Jul '14

Maybe we can do away with issue 9971 and improve readability: https://trac.torproject.org/projects/tor/ticket/9971 As response to this mail, I'll append seperate patches for the 3 sub-issues mentioned. They apply (and are build-tested) seperately to the current tree, so a maintainer can quickly pick one of them up, if happy with it. There shouldn't be a conflict in *1* and *2* but I could append a patchset anyway. sub-issue *3* is *only* a call for advice and will be written on top of the other ones, after discussion. 1* rename entry_guard_t's made_contact to used_so_save_if_down I think that's readable. Is that about what arma had in mind? 2* rename for_discovery argument of add_an_entry_guard() to I like probationary more than provisional. Those 2 are suggested in issue 9971. I chose forced_probationary for now, because isn't it strictly a suboptimal situation in terms of desired 'grade of anonymity'. What do you think? 3* NEEDS REVIEW FIRST: regarding the int arguments of add_an_entry_guard(). I look at: node_t *chosen is a node to add. prepend is set if the guard should become first in the list? there are 2 users of add_an_entry_guard() that pass it a chosen node. One is a bridge (prepend) and the other one is a user-defined node (!prepend), so: Given the fact that the list is not supposed to be long and the two 'users' are somewhat similar, why not prepend the node if explicitly given?

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