| 1 | =head1 NAME |
1 | =head1 NAME |
| 2 | |
2 | |
| 3 | AnyEvent::MP::Transport - actual transport protocol |
3 | AnyEvent::MP::Transport - actual transport protocol handler |
| 4 | |
4 | |
| 5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
| 6 | |
6 | |
| 7 | use AnyEvent::MP::Transport; |
7 | use AnyEvent::MP::Transport; |
| 8 | |
8 | |
| 9 | =head1 DESCRIPTION |
9 | =head1 DESCRIPTION |
| 10 | |
10 | |
| 11 | This is the superclass for MP transports, most of which is considered an |
11 | This implements the actual transport protocol for MP (it represents a |
| 12 | implementation detail. |
12 | single link), most of which is considered an implementation detail. |
| 13 | |
13 | |
| 14 | See the "PROTOCOL" section below if you want to write another client for |
14 | See the "PROTOCOL" section below if you want to write another client for |
| 15 | this protocol. |
15 | this protocol. |
| 16 | |
16 | |
| 17 | =head1 FUNCTIONS/METHODS |
17 | =head1 FUNCTIONS/METHODS |
| … | |
… | |
| 111 | |
111 | |
| 112 | =cut |
112 | =cut |
| 113 | |
113 | |
| 114 | our @FRAMINGS = qw(json storable); # the framing types we accept and send, in order of preference |
114 | our @FRAMINGS = qw(json storable); # the framing types we accept and send, in order of preference |
| 115 | our @AUTH_SND = qw(hmac_md6_64_256); # auth types we send |
115 | our @AUTH_SND = qw(hmac_md6_64_256); # auth types we send |
| 116 | our @AUTH_RCV = (@AUTH_SND, qw(hex_secret)); # auth types we accept |
116 | our @AUTH_RCV = (@AUTH_SND, qw(cleartext)); # auth types we accept |
| 117 | |
117 | |
| 118 | #AnyEvent::Handle::register_write_type mp_record => sub { |
118 | #AnyEvent::Handle::register_write_type mp_record => sub { |
| 119 | #}; |
119 | #}; |
| 120 | |
120 | |
| 121 | sub new { |
121 | sub new { |
| … | |
… | |
| 141 | $arg{secret} = AnyEvent::MP::Base::default_secret () |
141 | $arg{secret} = AnyEvent::MP::Base::default_secret () |
| 142 | unless exists $arg{secret}; |
142 | unless exists $arg{secret}; |
| 143 | |
143 | |
| 144 | $self->{hdl} = new AnyEvent::Handle |
144 | $self->{hdl} = new AnyEvent::Handle |
| 145 | fh => delete $arg{fh}, |
145 | fh => delete $arg{fh}, |
| 146 | rbuf_max => 64 * 1024, |
|
|
| 147 | autocork => 1, |
146 | autocork => 1, |
| 148 | no_delay => 1, |
147 | no_delay => 1, |
| 149 | on_error => sub { |
148 | on_error => sub { |
| 150 | $self->error ($_[2]); |
149 | $self->error ($_[2]); |
| 151 | }, |
150 | }, |
| … | |
… | |
| 158 | if $arg{tls_ctx}; |
157 | if $arg{tls_ctx}; |
| 159 | $greeting_kv->{provider} = "AE-$VERSION"; |
158 | $greeting_kv->{provider} = "AE-$VERSION"; |
| 160 | $greeting_kv->{peeraddr} = AnyEvent::Socket::format_hostport $self->{peerhost}, $self->{peerport}; |
159 | $greeting_kv->{peeraddr} = AnyEvent::Socket::format_hostport $self->{peerhost}, $self->{peerport}; |
| 161 | |
160 | |
| 162 | # send greeting |
161 | # send greeting |
| 163 | my $lgreeting1 = "aemp;$PROTOCOL_VERSION;$PROTOCOL_VERSION" # version, min |
162 | my $lgreeting1 = "aemp;$PROTOCOL_VERSION" |
| 164 | . ";$AnyEvent::MP::Base::UNIQ" |
163 | . ";$AnyEvent::MP::Base::UNIQ" |
| 165 | . ";$AnyEvent::MP::Base::NODE" |
164 | . ";$AnyEvent::MP::Base::NODE" |
| 166 | . ";" . (join ",", @AUTH_RCV) |
165 | . ";" . (join ",", @AUTH_RCV) |
| 167 | . ";" . (join ",", @FRAMINGS) |
166 | . ";" . (join ",", @FRAMINGS) |
| 168 | . (join "", map ";$_=$greeting_kv->{$_}", keys %$greeting_kv); |
167 | . (join "", map ";$_=$greeting_kv->{$_}", keys %$greeting_kv); |
|
|
168 | |
| 169 | my $lgreeting2 = MIME::Base64::encode_base64 AnyEvent::MP::Base::nonce (33), ""; |
169 | my $lgreeting2 = MIME::Base64::encode_base64 AnyEvent::MP::Base::nonce (33), ""; |
| 170 | |
170 | |
| 171 | $self->{hdl}->push_write ("$lgreeting1\012$lgreeting2\012"); |
171 | $self->{hdl}->push_write ("$lgreeting1\012$lgreeting2\012"); |
| 172 | |
172 | |
| 173 | # expect greeting |
173 | # expect greeting |
|
|
174 | $self->{hdl}->rbuf_max (4 * 1024); |
| 174 | $self->{hdl}->push_read (line => sub { |
175 | $self->{hdl}->push_read (line => sub { |
| 175 | my $rgreeting1 = $_[1]; |
176 | my $rgreeting1 = $_[1]; |
| 176 | |
177 | |
| 177 | my ($aemp, $version, $version_min, $uniq, $rnode, $auths, $framings, @kv) = split /;/, $rgreeting1; |
178 | my ($aemp, $version, $uniq, $rnode, $auths, $framings, @kv) = split /;/, $rgreeting1; |
| 178 | |
179 | |
| 179 | if ($aemp ne "aemp") { |
180 | if ($aemp ne "aemp") { |
| 180 | return $self->error ("unparsable greeting"); |
181 | return $self->error ("unparsable greeting"); |
| 181 | } elsif ($version_min > $PROTOCOL_VERSION) { |
182 | } elsif ($version != $PROTOCOL_VERSION) { |
| 182 | return $self->error ("version mismatch (we: $PROTOCOL_VERSION, they: $version_min .. $version)"); |
183 | return $self->error ("version mismatch (we: $PROTOCOL_VERSION, they: $version)"); |
| 183 | } |
184 | } |
| 184 | |
185 | |
| 185 | my $s_auth; |
186 | my $s_auth; |
| 186 | for my $auth_ (split /,/, $auths) { |
187 | for my $auth_ (split /,/, $auths) { |
| 187 | if (grep $auth_ eq $_, @AUTH_SND) { |
188 | if (grep $auth_ eq $_, @AUTH_SND) { |
| … | |
… | |
| 226 | # auth |
227 | # auth |
| 227 | require Digest::MD6; |
228 | require Digest::MD6; |
| 228 | require Digest::HMAC_MD6; |
229 | require Digest::HMAC_MD6; |
| 229 | |
230 | |
| 230 | my $key = Digest::MD6::md6 ($secret); |
231 | my $key = Digest::MD6::md6 ($secret); |
| 231 | my $lauth = Digest::HMAC_MD6::hmac_md6_base64 ($key, "$lgreeting1\012$lgreeting2\012$rgreeting1\012$rgreeting2\012", 64, 256); |
232 | my $lauth = Digest::HMAC_MD6::hmac_md6_hex ($key, "$lgreeting1\012$lgreeting2\012$rgreeting1\012$rgreeting2\012", 64, 256); |
| 232 | |
233 | |
| 233 | my $rauth = |
234 | my $rauth = |
| 234 | $s_auth eq "hmac_md6_64_256" ? Digest::HMAC_MD6::hmac_md6_base64 ($key, "$rgreeting1\012$rgreeting2\012$lgreeting1\012$lgreeting2\012", 64, 256) |
235 | $s_auth eq "hmac_md6_64_256" ? Digest::HMAC_MD6::hmac_md6_hex ($key, "$rgreeting1\012$rgreeting2\012$lgreeting1\012$lgreeting2\012", 64, 256) |
| 235 | : $s_auth eq "hex_secret" ? unpack "H*", $secret |
236 | : $s_auth eq "cleartext" ? unpack "H*", $secret |
| 236 | : die; |
237 | : die; |
| 237 | |
238 | |
| 238 | $lauth ne $rauth # echo attack? |
239 | $lauth ne $rauth # echo attack? |
| 239 | or return $self->error ("authentication error"); |
240 | or return $self->error ("authentication error"); |
| 240 | |
241 | |
| 241 | $self->{hdl}->push_write ("$s_auth;$lauth;$s_framing\012"); |
242 | $self->{hdl}->push_write ("$s_auth;$lauth;$s_framing\012"); |
| 242 | |
243 | |
| 243 | $self->{hdl}->rbuf_max (64); # enough for 44 reply bytes or so |
244 | # reasd the authentication response |
| 244 | $self->{hdl}->push_read (line => sub { |
245 | $self->{hdl}->push_read (line => sub { |
| 245 | my ($hdl, $rline) = @_; |
246 | my ($hdl, $rline) = @_; |
| 246 | |
247 | |
| 247 | my ($auth_method, $rauth2, $r_framing) = split /;/, $rline; |
248 | my ($auth_method, $rauth2, $r_framing) = split /;/, $rline; |
| 248 | |
249 | |
| … | |
… | |
| 255 | $hdl->rbuf_max (undef); |
256 | $hdl->rbuf_max (undef); |
| 256 | my $queue = delete $self->{queue}; # we are connected |
257 | my $queue = delete $self->{queue}; # we are connected |
| 257 | |
258 | |
| 258 | $self->connected; |
259 | $self->connected; |
| 259 | |
260 | |
|
|
261 | my $src_node = $self->{node}; |
|
|
262 | |
| 260 | $hdl->push_write ($self->{s_framing} => $_) |
263 | $hdl->push_write ($self->{s_framing} => $_) |
| 261 | for @$queue; |
264 | for @$queue; |
| 262 | |
265 | |
| 263 | my $rmsg; $rmsg = sub { |
266 | my $rmsg; $rmsg = sub { |
| 264 | $_[0]->push_read ($r_framing => $rmsg); |
267 | $_[0]->push_read ($r_framing => $rmsg); |
| 265 | |
268 | |
|
|
269 | local $AnyEvent::MP::Base::SRCNODE = $src_node; |
| 266 | AnyEvent::MP::Base::_inject ($_[1]); |
270 | AnyEvent::MP::Base::_inject (@{ $_[1] }); |
| 267 | }; |
271 | }; |
| 268 | $hdl->push_read ($r_framing => $rmsg); |
272 | $hdl->push_read ($r_framing => $rmsg); |
| 269 | }); |
273 | }); |
| 270 | }); |
274 | }); |
| 271 | }); |
275 | }); |
| … | |
… | |
| 322 | The greeting consists of two text lines that are ended by either an ASCII |
326 | The greeting consists of two text lines that are ended by either an ASCII |
| 323 | CR LF pair, or a single ASCII LF (recommended). |
327 | CR LF pair, or a single ASCII LF (recommended). |
| 324 | |
328 | |
| 325 | =head2 GREETING |
329 | =head2 GREETING |
| 326 | |
330 | |
|
|
331 | All the lines until after authentication must not exceed 4kb in length, |
|
|
332 | including delimiter. Afterwards there is no limit on the packet size that |
|
|
333 | can be received. |
|
|
334 | |
|
|
335 | =head3 First Greeting Line |
|
|
336 | |
|
|
337 | Example: |
|
|
338 | |
|
|
339 | aemp;0;fec.4a7720fc;127.0.0.1:1235,[::1]:1235;hmac_md6_64_256;json,storable;provider=AE-0.0 |
|
|
340 | |
| 327 | The first line contains strings separated (not ended) by C<;> |
341 | The first line contains strings separated (not ended) by C<;> |
| 328 | characters. The first seven strings are fixed by the protocol, the |
342 | characters. The first even ixtrings are fixed by the protocol, the |
| 329 | remaining strings are C<KEY=VALUE> pairs. None of them may contain C<;> |
343 | remaining strings are C<KEY=VALUE> pairs. None of them may contain C<;> |
| 330 | characters themselves. |
344 | characters themselves. |
| 331 | |
345 | |
| 332 | The seven fixed strings are: |
346 | The fixed strings are: |
| 333 | |
347 | |
| 334 | =over 4 |
348 | =over 4 |
| 335 | |
349 | |
| 336 | =item C<aemp> |
350 | =item C<aemp> |
| 337 | |
351 | |
| 338 | The constant C<aemp> to identify the protocol. |
352 | The constant C<aemp> to identify the protocol. |
| 339 | |
353 | |
| 340 | =item protocol version |
354 | =item protocol version |
| 341 | |
355 | |
| 342 | The (maximum) protocol version supported by this end, currently C<0>. |
|
|
| 343 | |
|
|
| 344 | =item minimum protocol version |
|
|
| 345 | |
|
|
| 346 | The minimum protocol version supported by this end, currently C<0>. |
356 | The protocol version supported by this end, currently C<0>. If the |
|
|
357 | versions don't match then no communication is possible. Minor extensions |
|
|
358 | are supposed to be handled by addign additional key-value pairs. |
| 347 | |
359 | |
| 348 | =item a token uniquely identifying the current node instance |
360 | =item a token uniquely identifying the current node instance |
| 349 | |
361 | |
| 350 | This is a string that must change between restarts. It usually contains |
362 | This is a string that must change between restarts. It usually contains |
| 351 | things like the current time, the (OS) process id or similar values, but |
363 | things like the current time, the (OS) process id or similar values, but |
| … | |
… | |
| 392 | |
404 | |
| 393 | Indicates that the other side supports TLS (version should be 1.0) and |
405 | Indicates that the other side supports TLS (version should be 1.0) and |
| 394 | wishes to do a TLS handshake. |
406 | wishes to do a TLS handshake. |
| 395 | |
407 | |
| 396 | =back |
408 | =back |
|
|
409 | |
|
|
410 | =head3 Second Greeting Line |
| 397 | |
411 | |
| 398 | After this greeting line there will be a second line containing a |
412 | After this greeting line there will be a second line containing a |
| 399 | cryptographic nonce, i.e. random data of high quality. To keep the |
413 | cryptographic nonce, i.e. random data of high quality. To keep the |
| 400 | protocol text-only, these are usually 32 base64-encoded octets, but |
414 | protocol text-only, these are usually 32 base64-encoded octets, but |
| 401 | it could be anything that doesn't contain any ASCII CR or ASCII LF |
415 | it could be anything that doesn't contain any ASCII CR or ASCII LF |
| 402 | characters. |
416 | characters. |
| 403 | |
417 | |
| 404 | Example of the two lines of greeting: |
418 | I<< The two nonces B<must> be different, and an aemp implementation |
|
|
419 | B<must> check and fail when they are identical >>. |
| 405 | |
420 | |
| 406 | aemp;0;0;e7d.4a76f48f;10.0.0.1:4040;hmac_md6_64_256,hex_secret;json,storable;provider=AE-0.0;peeraddr=127.0.0.1:1235 |
421 | Example of a nonce line: |
| 407 | XntegV2Guvss0qNn7phCPnoU87xqxV+4Mqm/5y4iQm6a |
422 | |
|
|
423 | p/I122ql7kJR8lumW3lXlXCeBnyDAvz8NQo3x5IFowE4 |
| 408 | |
424 | |
| 409 | =head2 TLS handshake |
425 | =head2 TLS handshake |
| 410 | |
426 | |
| 411 | If, after the handshake, both sides indicate interest in TLS, then the |
427 | I<< If, after the handshake, both sides indicate interest in TLS, then the |
| 412 | connection I<must> use TLS, or fail. |
428 | connection B<must> use TLS, or fail.>> |
| 413 | |
429 | |
| 414 | Both sides compare their nonces, and the side who sent the lower nonce |
430 | Both sides compare their nonces, and the side who sent the lower nonce |
| 415 | value ("string" comparison on the raw octet values) becomes the client, |
431 | value ("string" comparison on the raw octet values) becomes the client, |
| 416 | and the one with the higher nonce the server. |
432 | and the one with the higher nonce the server. |
| 417 | |
433 | |
| … | |
… | |
| 428 | |
444 | |
| 429 | =item the authentication method chosen |
445 | =item the authentication method chosen |
| 430 | |
446 | |
| 431 | This must be one of the methods offered by the other side in the greeting. |
447 | This must be one of the methods offered by the other side in the greeting. |
| 432 | |
448 | |
|
|
449 | The currently supported authentication methods are: |
|
|
450 | |
|
|
451 | =over 4 |
|
|
452 | |
|
|
453 | =item cleartext |
|
|
454 | |
|
|
455 | This is simply the shared secret, lowercase-hex-encoded. This method is of |
|
|
456 | course very insecure, unless TLS is used, which is why this module will |
|
|
457 | accept, but not generate, cleartext auth replies. |
|
|
458 | |
|
|
459 | =item hmac_md6_64_256 |
|
|
460 | |
|
|
461 | This method uses an MD6 HMAC with 64 bit blocksize and 256 bit hash. First, the shared secret |
|
|
462 | is hashed with MD6: |
|
|
463 | |
|
|
464 | key = MD6 (secret) |
|
|
465 | |
|
|
466 | This secret is then used to generate the "local auth reply", by taking |
|
|
467 | the two local greeting lines and the two remote greeting lines (without |
|
|
468 | line endings), appending \012 to all of them, concatenating them and |
|
|
469 | calculating the MD6 HMAC with the key. |
|
|
470 | |
|
|
471 | lauth = HMAC_MD6 key, "lgreeting1\012lgreeting2\012rgreeting1\012rgreeting2\012" |
|
|
472 | |
|
|
473 | This authentication token is then lowercase-hex-encoded and sent to the |
|
|
474 | other side. |
|
|
475 | |
|
|
476 | Then the remote auth reply is generated using the same method, but local |
|
|
477 | and remote greeting lines swapped: |
|
|
478 | |
|
|
479 | rauth = HMAC_MD6 key, "rgreeting1\012rgreeting2\012lgreeting1\012lgreeting2\012" |
|
|
480 | |
|
|
481 | This is the token that is expected from the other side. |
|
|
482 | |
|
|
483 | =back |
|
|
484 | |
| 433 | =item the authentication data |
485 | =item the authentication data |
| 434 | |
486 | |
| 435 | The authentication data itself, usually base64 or hex-encoded data. |
487 | The authentication data itself, usually base64 or hex-encoded data, see |
|
|
488 | above. |
| 436 | |
489 | |
| 437 | =item the framing protocol chosen |
490 | =item the framing protocol chosen |
| 438 | |
491 | |
| 439 | This must be one of the framing protocols offered by the other side in the |
492 | This must be one of the framing protocols offered by the other side in the |
| 440 | greeting. Each side must accept the choice of the other side. |
493 | greeting. Each side must accept the choice of the other side. |
| 441 | |
494 | |
| 442 | =back |
495 | =back |
| 443 | |
496 | |
| 444 | Example (the actual reply matching the previous example): |
497 | Example of an authentication reply: |
| 445 | |
498 | |
| 446 | hmac_md6_64_256;wIlLedBY956UCGSISG9mBZRDTG8xUi73/sVse2DSQp0;json |
499 | hmac_md6_64_256;363d5175df38bd9eaddd3f6ca18aa1c0c4aa22f0da245ac638d048398c26b8d3;json |
| 447 | |
500 | |
| 448 | =head2 DATA PHASE |
501 | =head2 DATA PHASE |
| 449 | |
502 | |
| 450 | After this, packets get exchanged using the chosen framing protocol. It is |
503 | After this, packets get exchanged using the chosen framing protocol. It is |
| 451 | quite possible that both sides use a different framing protocol. |
504 | quite possible that both sides use a different framing protocol. |
| 452 | |
505 | |
|
|
506 | =head2 FULL EXAMPLE |
|
|
507 | |
|
|
508 | This is an actual protocol dump of a handshake, followed by a single data |
|
|
509 | packet. The greater than/less than lines indicate the direction of the |
|
|
510 | transfer only. |
|
|
511 | |
|
|
512 | > aemp;0;nndKd+gn;10.0.0.1:4040;hmac_md6_64_256,cleartext;json,storable;provider=AE-0.0;peeraddr=127.0.0.1:1235 |
|
|
513 | > sRG8bbc4TDbkpvH8FTP4HBs87OhepH6VuApoZqXXskuG |
|
|
514 | < aemp;0;nmpKd+gh;127.0.0.1:1235,[::1]:1235;hmac_md6_64_256,cleartext;json,storable;provider=AE-0.0;peeraddr=127.0.0.1:58760 |
|
|
515 | < dCEUcL/LJVSTJcx8byEsOzrwhzJYOq+L3YcopA5T6EAo |
|
|
516 | > hmac_md6_64_256;9513d4b258975accfcb2ab7532b83690e9c119a502c612203332a591c7237788;json |
|
|
517 | < hmac_md6_64_256;0298d6ba2240faabb2b2e881cf86b97d70a113ca74a87dc006f9f1e9d3010f90;json |
|
|
518 | > ["","wkp","pinger","10.0.0.1:4040#nndKd+gn.a","resolved"] |
|
|
519 | |
| 453 | =head1 SEE ALSO |
520 | =head1 SEE ALSO |
| 454 | |
521 | |
| 455 | L<AnyEvent>. |
522 | L<AnyEvent>. |
| 456 | |
523 | |
| 457 | =head1 AUTHOR |
524 | =head1 AUTHOR |
