… | |
… | |
9 | =head1 DESCRIPTION |
9 | =head1 DESCRIPTION |
10 | |
10 | |
11 | This is the superclass for MP transports, most of which is considered an |
11 | This is the superclass for MP transports, most of which is considered an |
12 | implementation detail. |
12 | implementation detail. |
13 | |
13 | |
14 | Future versions might document the actual protocol. |
14 | See the "PROTOCOL" section below if you want to write another client for |
|
|
15 | this protocol. |
15 | |
16 | |
16 | =head1 FUNCTIONS/METHODS |
17 | =head1 FUNCTIONS/METHODS |
17 | |
18 | |
18 | =over 4 |
19 | =over 4 |
19 | |
20 | |
… | |
… | |
30 | |
31 | |
31 | use AE (); |
32 | use AE (); |
32 | use AnyEvent::Socket (); |
33 | use AnyEvent::Socket (); |
33 | use AnyEvent::Handle (); |
34 | use AnyEvent::Handle (); |
34 | |
35 | |
35 | use AnyEvent::MP::Util (); |
|
|
36 | |
|
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37 | use base Exporter::; |
36 | use base Exporter::; |
38 | |
37 | |
39 | our $VERSION = '0.0'; |
38 | our $VERSION = '0.0'; |
40 | our $PROTOCOL_VERSION = 0; |
39 | our $PROTOCOL_VERSION = 0; |
41 | |
40 | |
… | |
… | |
44 | Creates a listener on the given host/port using |
43 | Creates a listener on the given host/port using |
45 | C<AnyEvent::Socket::tcp_server>. |
44 | C<AnyEvent::Socket::tcp_server>. |
46 | |
45 | |
47 | See C<new>, below, for constructor arguments. |
46 | See C<new>, below, for constructor arguments. |
48 | |
47 | |
49 | Defaults for peerhost, peerport, fh and tls are provided. |
48 | Defaults for peerhost, peerport and fh are provided. |
50 | |
49 | |
51 | =cut |
50 | =cut |
52 | |
51 | |
53 | sub mp_server($$@) { |
52 | sub mp_server($$@) { |
54 | my $cb = pop; |
53 | my $cb = pop; |
… | |
… | |
59 | |
58 | |
60 | $cb->(new AnyEvent::MP::Transport |
59 | $cb->(new AnyEvent::MP::Transport |
61 | fh => $fh, |
60 | fh => $fh, |
62 | peerhost => $host, |
61 | peerhost => $host, |
63 | peerport => $port, |
62 | peerport => $port, |
64 | tls => "accept", |
|
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65 | @args, |
63 | @args, |
66 | ); |
64 | ); |
67 | } |
65 | } |
68 | } |
66 | } |
69 | |
67 | |
… | |
… | |
83 | $cb->(new AnyEvent::MP::Transport |
81 | $cb->(new AnyEvent::MP::Transport |
84 | fh => $fh, |
82 | fh => $fh, |
85 | peername => $host, |
83 | peername => $host, |
86 | peerhost => $nhost, |
84 | peerhost => $nhost, |
87 | peerport => $nport, |
85 | peerport => $nport, |
88 | tls => "accept", |
|
|
89 | @args, |
86 | @args, |
90 | ); |
87 | ); |
91 | } |
88 | } |
92 | } |
89 | } |
93 | |
90 | |
… | |
… | |
106 | on_eof => sub { clean-close-callback }, |
103 | on_eof => sub { clean-close-callback }, |
107 | on_connect => sub { successful-connect-callback }, |
104 | on_connect => sub { successful-connect-callback }, |
108 | greeting => { key => value }, |
105 | greeting => { key => value }, |
109 | |
106 | |
110 | # tls support |
107 | # tls support |
111 | tls => "accept|connect", |
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112 | tls_ctx => AnyEvent::TLS, |
108 | tls_ctx => AnyEvent::TLS, |
113 | peername => $peername, # for verification |
109 | peername => $peername, # for verification |
114 | ; |
110 | ; |
115 | |
111 | |
116 | =cut |
112 | =cut |
117 | |
113 | |
118 | our @FRAMING_WANT = qw(json storable);#d##TODO# |
114 | our @FRAMINGS = qw(json storable); # the framing types we accept and send, in order of preference |
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115 | our @AUTH_SND = qw(hmac_md6_64_256); # auth types we send |
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116 | our @AUTH_RCV = (@AUTH_SND, qw(hex_secret)); # auth types we accept |
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117 | |
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118 | #AnyEvent::Handle::register_write_type mp_record => sub { |
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119 | #}; |
119 | |
120 | |
120 | sub new { |
121 | sub new { |
121 | my ($class, %arg) = @_; |
122 | my ($class, %arg) = @_; |
122 | |
123 | |
123 | my $self = bless \%arg, $class; |
124 | my $self = bless \%arg, $class; |
… | |
… | |
125 | $self->{queue} = []; |
126 | $self->{queue} = []; |
126 | |
127 | |
127 | { |
128 | { |
128 | Scalar::Util::weaken (my $self = $self); |
129 | Scalar::Util::weaken (my $self = $self); |
129 | |
130 | |
130 | if (exists $arg{connect}) { |
131 | $arg{tls_ctx_disabled} ||= { |
131 | $arg{tls} ||= "connect"; |
132 | sslv2 => 0, |
132 | $arg{tls_ctx} ||= { sslv2 => 0, sslv3 => 0, tlsv1 => 1, verify => 1 }; |
133 | sslv3 => 0, |
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134 | tlsv1 => 1, |
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135 | verify => 1, |
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136 | cert_file => "secret.pem", |
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137 | ca_file => "secret.pem", |
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138 | verify_require_client_cert => 1, |
133 | } |
139 | }; |
134 | |
140 | |
135 | $arg{secret} = AnyEvent::MP::default_secret () |
141 | $arg{secret} = AnyEvent::MP::Base::default_secret () |
136 | unless exists $arg{secret}; |
142 | unless exists $arg{secret}; |
137 | |
143 | |
138 | $self->{hdl} = new AnyEvent::Handle |
144 | $self->{hdl} = new AnyEvent::Handle |
139 | fh => delete $arg{fh}, |
145 | fh => delete $arg{fh}, |
140 | rbuf_max => 64 * 1024, |
146 | rbuf_max => 64 * 1024, |
… | |
… | |
146 | peername => delete $arg{peername}, |
152 | peername => delete $arg{peername}, |
147 | ; |
153 | ; |
148 | |
154 | |
149 | my $secret = $arg{secret}; |
155 | my $secret = $arg{secret}; |
150 | my $greeting_kv = $self->{greeting} ||= {}; |
156 | my $greeting_kv = $self->{greeting} ||= {}; |
151 | $greeting_kv->{"tls1.0"} ||= $arg{tls} |
157 | $greeting_kv->{"tls"} = "1.0" |
152 | if exists $arg{tls} && $arg{tls_ctx}; |
158 | if $arg{tls_ctx}; |
153 | $greeting_kv->{provider} = "AE-$VERSION"; |
159 | $greeting_kv->{provider} = "AE-$VERSION"; |
|
|
160 | $greeting_kv->{peeraddr} = AnyEvent::Socket::format_hostport $self->{peerhost}, $self->{peerport}; |
154 | |
161 | |
155 | # send greeting |
162 | # send greeting |
156 | my $lgreeting = "aemp;$PROTOCOL_VERSION;$PROTOCOL_VERSION" # version, min |
163 | my $lgreeting1 = "aemp;$PROTOCOL_VERSION;$PROTOCOL_VERSION" # version, min |
157 | . ";$AnyEvent::MP::UNIQ" |
164 | . ";$AnyEvent::MP::Base::UNIQ" |
158 | . ";$AnyEvent::MP::NODE" |
165 | . ";$AnyEvent::MP::Base::NODE" |
159 | . ";" . (MIME::Base64::encode_base64 AnyEvent::MP::Util::nonce 33, "") |
166 | . ";" . (join ",", @AUTH_RCV) |
160 | . ";hmac_md6_64_256" # hardcoded atm. |
167 | . ";" . (join ",", @FRAMINGS) |
161 | . ";json" # hardcoded atm. |
|
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162 | . ";$self->{peerhost};$self->{peerport}" |
|
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163 | . (join "", map ";$_=$greeting_kv->{$_}", keys %$greeting_kv); |
168 | . (join "", map ";$_=$greeting_kv->{$_}", keys %$greeting_kv); |
|
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169 | my $lgreeting2 = MIME::Base64::encode_base64 AnyEvent::MP::Base::nonce (33), ""; |
164 | |
170 | |
165 | $self->{hdl}->push_write ("$lgreeting\012"); |
171 | $self->{hdl}->push_write ("$lgreeting1\012$lgreeting2\012"); |
166 | |
172 | |
167 | # expect greeting |
173 | # expect greeting |
168 | $self->{hdl}->push_read (line => sub { |
174 | $self->{hdl}->push_read (line => sub { |
169 | my $rgreeting = $_[1]; |
175 | my $rgreeting1 = $_[1]; |
170 | |
176 | |
171 | my ($aemp, $version, $version_min, $uniq, $rnode, undef, $auth, $framing, $peerport, $peerhost, @kv) = split /;/, $rgreeting; |
177 | my ($aemp, $version, $version_min, $uniq, $rnode, $auths, $framings, @kv) = split /;/, $rgreeting1; |
172 | |
178 | |
173 | if ($aemp ne "aemp") { |
179 | if ($aemp ne "aemp") { |
174 | return $self->error ("unparsable greeting"); |
180 | return $self->error ("unparsable greeting"); |
175 | } elsif ($version_min > $PROTOCOL_VERSION) { |
181 | } elsif ($version_min > $PROTOCOL_VERSION) { |
176 | return $self->error ("version mismatch (we: $PROTOCOL_VERSION, they: $version_min .. $version)"); |
182 | return $self->error ("version mismatch (we: $PROTOCOL_VERSION, they: $version_min .. $version)"); |
177 | } elsif ($auth ne "hmac_md6_64_256") { |
|
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178 | return $self->error ("unsupported auth method ($auth)"); |
|
|
179 | } elsif ($framing ne "json") { |
|
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180 | return $self->error ("unsupported framing method ($auth)"); |
|
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181 | } |
183 | } |
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184 | |
|
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185 | my $s_auth; |
|
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186 | for my $auth_ (split /,/, $auths) { |
|
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187 | if (grep $auth_ eq $_, @AUTH_SND) { |
|
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188 | $s_auth = $auth_; |
|
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189 | last; |
|
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190 | } |
|
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191 | } |
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192 | |
|
|
193 | defined $s_auth |
|
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194 | or return $self->error ("$auths: no common auth type supported"); |
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195 | |
|
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196 | die unless $s_auth eq "hmac_md6_64_256"; # hardcoded atm. |
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197 | |
|
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198 | my $s_framing; |
|
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199 | for my $framing_ (split /,/, $framings) { |
|
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200 | if (grep $framing_ eq $_, @FRAMINGS) { |
|
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201 | $s_framing = $framing_; |
|
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202 | last; |
|
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203 | } |
|
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204 | } |
|
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205 | |
|
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206 | defined $s_framing |
|
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207 | or return $self->error ("$framings: no common framing method supported"); |
182 | |
208 | |
183 | $self->{remote_uniq} = $uniq; |
209 | $self->{remote_uniq} = $uniq; |
184 | $self->{remote_node} = $rnode; |
210 | $self->{remote_node} = $rnode; |
185 | |
211 | |
186 | $self->{remote_greeting} = { |
212 | $self->{remote_greeting} = { |
187 | map /^([^=]+)(?:=(.*))?/ ? ($1 => $2) : (), |
213 | map /^([^=]+)(?:=(.*))?/ ? ($1 => $2) : (), |
188 | @kv |
214 | @kv |
189 | }; |
215 | }; |
190 | |
216 | |
191 | if (exists $self->{tls} and $self->{tls_ctx} and exists $self->{remote_greeting}{"tls1.0"}) { |
217 | # read nonce |
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218 | $self->{hdl}->push_read (line => sub { |
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219 | my $rgreeting2 = $_[1]; |
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220 | |
192 | if ($self->{tls} ne $self->{remote_greeting}{"tls1.0"}) { |
221 | if ($self->{tls_ctx} and 1 == int $self->{remote_greeting}{tls}) { |
193 | return $self->error ("TLS server/client mismatch"); |
222 | $self->{tls} = $lgreeting2 lt $rgreeting2 ? "connect" : "accept"; |
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223 | $self->{hdl}->starttls ($self->{tls}, $self->{tls_ctx}); |
194 | } |
224 | } |
195 | $self->{hdl}->starttls ($self->{tls}, $self->{tls_ctx}); |
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196 | } |
225 | |
197 | |
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198 | # auth |
226 | # auth |
199 | require Digest::MD6; |
227 | require Digest::MD6; |
200 | require Digest::HMAC_MD6; |
228 | require Digest::HMAC_MD6; |
201 | |
229 | |
202 | my $key = Digest::MD6::md6_hex ($secret); |
230 | my $key = Digest::MD6::md6 ($secret); |
203 | my $lauth = Digest::HMAC_MD6::hmac_md6_base64 ($key, "$lgreeting\012$rgreeting", 64, 256); |
231 | my $lauth = Digest::HMAC_MD6::hmac_md6_base64 ($key, "$lgreeting1\012$lgreeting2\012$rgreeting1\012$rgreeting2\012", 64, 256); |
204 | my $rauth = Digest::HMAC_MD6::hmac_md6_base64 ($key, "$rgreeting\012$lgreeting", 64, 256); |
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205 | |
232 | |
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233 | my $rauth = |
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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) |
|
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235 | : $s_auth eq "hex_secret" ? unpack "H*", $secret |
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236 | : die; |
|
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237 | |
206 | $lauth ne $rauth # echo attack? |
238 | $lauth ne $rauth # echo attack? |
207 | or return $self->error ("authentication error"); |
239 | or return $self->error ("authentication error"); |
208 | |
240 | |
209 | $self->{hdl}->push_write ("$auth;$lauth;$framing\012"); |
241 | $self->{hdl}->push_write ("$s_auth;$lauth;$s_framing\012"); |
210 | |
242 | |
211 | $self->{hdl}->rbuf_max (64); # enough for 44 reply bytes or so |
243 | $self->{hdl}->rbuf_max (64); # enough for 44 reply bytes or so |
212 | $self->{hdl}->push_read (line => sub { |
244 | $self->{hdl}->push_read (line => sub { |
213 | my ($hdl, $rline) = @_; |
245 | my ($hdl, $rline) = @_; |
214 | |
246 | |
215 | my ($auth_method, $rauth2, $r_framing) = split /;/, $rline; |
247 | my ($auth_method, $rauth2, $r_framing) = split /;/, $rline; |
216 | |
248 | |
217 | if ($rauth2 ne $rauth) { |
249 | if ($rauth2 ne $rauth) { |
218 | return $self->error ("authentication failure/shared secret mismatch"); |
250 | return $self->error ("authentication failure/shared secret mismatch"); |
219 | } |
251 | } |
220 | |
252 | |
221 | $self->{s_framing} = "json";#d# |
253 | $self->{s_framing} = $s_framing; |
222 | |
254 | |
223 | $hdl->rbuf_max (undef); |
255 | $hdl->rbuf_max (undef); |
224 | my $queue = delete $self->{queue}; # we are connected |
256 | my $queue = delete $self->{queue}; # we are connected |
225 | |
257 | |
226 | $self->connected; |
258 | $self->connected; |
227 | |
259 | |
228 | $hdl->push_write ($self->{s_framing} => $_) |
260 | $hdl->push_write ($self->{s_framing} => $_) |
229 | for @$queue; |
261 | for @$queue; |
230 | |
262 | |
231 | my $rmsg; $rmsg = sub { |
263 | my $rmsg; $rmsg = sub { |
232 | $_[0]->push_read ($r_framing => $rmsg); |
264 | $_[0]->push_read ($r_framing => $rmsg); |
233 | |
265 | |
234 | AnyEvent::MP::_inject ($_[1]); |
266 | AnyEvent::MP::Base::_inject ($_[1]); |
235 | }; |
267 | }; |
236 | $hdl->push_read ($r_framing => $rmsg); |
268 | $hdl->push_read ($r_framing => $rmsg); |
|
|
269 | }); |
237 | }); |
270 | }); |
238 | }); |
271 | }); |
239 | } |
272 | } |
240 | |
273 | |
241 | $self |
274 | $self |
… | |
… | |
245 | my ($self, $msg) = @_; |
278 | my ($self, $msg) = @_; |
246 | |
279 | |
247 | if ($self->{node} && $self->{node}{transport} == $self) { |
280 | if ($self->{node} && $self->{node}{transport} == $self) { |
248 | $self->{node}->clr_transport; |
281 | $self->{node}->clr_transport; |
249 | } |
282 | } |
250 | # $self->{on_error}($self, $msg); |
283 | $AnyEvent::MP::Base::WARN->("$self->{peerhost}:$self->{peerport}: $msg"); |
251 | $self->destroy; |
284 | $self->destroy; |
252 | } |
285 | } |
253 | |
286 | |
254 | sub connected { |
287 | sub connected { |
255 | my ($self) = @_; |
288 | my ($self) = @_; |
256 | |
289 | |
257 | my $node = AnyEvent::MP::add_node ($self->{remote_node}); |
290 | my $node = AnyEvent::MP::Base::add_node ($self->{remote_node}); |
258 | Scalar::Util::weaken ($self->{node} = $node); |
291 | Scalar::Util::weaken ($self->{node} = $node); |
259 | $node->set_transport ($self); |
292 | $node->set_transport ($self); |
260 | } |
293 | } |
261 | |
294 | |
262 | sub send { |
295 | sub send { |
… | |
… | |
276 | $self->destroy; |
309 | $self->destroy; |
277 | } |
310 | } |
278 | |
311 | |
279 | =back |
312 | =back |
280 | |
313 | |
|
|
314 | =head1 PROTOCOL |
|
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315 | |
|
|
316 | The protocol is relatively simple, and consists of three phases which are |
|
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317 | symmetrical for both sides: greeting (followed by optionally switching to |
|
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318 | TLS mode), authentication and packet exchange. |
|
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319 | |
|
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320 | the protocol is designed to allow both full-text and binary streams. |
|
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321 | |
|
|
322 | The greeting consists of two text lines that are ended by either an ASCII |
|
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323 | CR LF pair, or a single ASCII LF (recommended). |
|
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324 | |
|
|
325 | =head2 GREETING |
|
|
326 | |
|
|
327 | The first line contains strings separated (not ended) by C<;> |
|
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328 | characters. The first seven strings are fixed by the protocol, the |
|
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329 | remaining strings are C<KEY=VALUE> pairs. None of them may contain C<;> |
|
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330 | characters themselves. |
|
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331 | |
|
|
332 | The seven fixed strings are: |
|
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333 | |
|
|
334 | =over 4 |
|
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335 | |
|
|
336 | =item C<aemp> |
|
|
337 | |
|
|
338 | The constant C<aemp> to identify the protocol. |
|
|
339 | |
|
|
340 | =item protocol version |
|
|
341 | |
|
|
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>. |
|
|
347 | |
|
|
348 | =item a token uniquely identifying the current node instance |
|
|
349 | |
|
|
350 | 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 |
|
|
352 | no meaning of the contents are assumed. |
|
|
353 | |
|
|
354 | =item the node endpoint descriptors |
|
|
355 | |
|
|
356 | for public nodes, this is a comma-separated list of protocol endpoints, |
|
|
357 | i.e., the noderef. For slave nodes, this is a unique identifier. |
|
|
358 | |
|
|
359 | =item the acceptable authentication methods |
|
|
360 | |
|
|
361 | A comma-separated list of authentication methods supported by the |
|
|
362 | node. Note that AnyEvent::MP supports a C<hex_secret> authentication |
|
|
363 | method that accepts a cleartext password (hex-encoded), but will not use |
|
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364 | this auth method itself. |
|
|
365 | |
|
|
366 | The receiving side should choose the first auth method it supports. |
|
|
367 | |
|
|
368 | =item the acceptable framing formats |
|
|
369 | |
|
|
370 | A comma-separated list of packet encoding/framign formats understood. The |
|
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371 | receiving side should choose the first framing format it supports for |
|
|
372 | sending packets (which might be different from the format it has to accept). |
|
|
373 | |
|
|
374 | =back |
|
|
375 | |
|
|
376 | The remaining arguments are C<KEY=VALUE> pairs. The following key-value |
|
|
377 | pairs are known at this time: |
|
|
378 | |
|
|
379 | =over 4 |
|
|
380 | |
|
|
381 | =item provider=<module-version> |
|
|
382 | |
|
|
383 | The software provider for this implementation. For AnyEvent::MP, this is |
|
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384 | C<AE-0.0> or whatever version it currently is at. |
|
|
385 | |
|
|
386 | =item peeraddr=<host>:<port> |
|
|
387 | |
|
|
388 | The peer address (socket address of the other side) as seen locally, in the same format |
|
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389 | as noderef endpoints. |
|
|
390 | |
|
|
391 | =item tls=<major>.<minor> |
|
|
392 | |
|
|
393 | Indicates that the other side supports TLS (version should be 1.0) and |
|
|
394 | wishes to do a TLS handshake. |
|
|
395 | |
|
|
396 | =back |
|
|
397 | |
|
|
398 | 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 |
|
|
400 | 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 |
|
|
402 | characters. |
|
|
403 | |
|
|
404 | Example of the two lines of greeting: |
|
|
405 | |
|
|
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 |
|
|
407 | XntegV2Guvss0qNn7phCPnoU87xqxV+4Mqm/5y4iQm6a |
|
|
408 | |
|
|
409 | =head2 TLS handshake |
|
|
410 | |
|
|
411 | If, after the handshake, both sides indicate interest in TLS, then the |
|
|
412 | connection I<must> use TLS, or fail. |
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413 | |
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414 | Both sides compare their nonces, and the side who sent the lower nonce |
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415 | value ("string" comparison on the raw octet values) becomes the client, |
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416 | and the one with the higher nonce the server. |
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417 | |
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418 | =head2 AUTHENTICATION PHASE |
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419 | |
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420 | After the greeting is received (and the optional TLS handshake), |
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421 | the authentication phase begins, which consists of sending a single |
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422 | C<;>-separated line with three fixed strings and any number of |
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423 | C<KEY=VALUE> pairs. |
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424 | |
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425 | The three fixed strings are: |
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426 | |
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427 | =over 4 |
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428 | |
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429 | =item the authentication method chosen |
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430 | |
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431 | This must be one of the methods offered by the other side in the greeting. |
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432 | |
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433 | =item the authentication data |
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434 | |
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435 | The authentication data itself, usually base64 or hex-encoded data. |
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436 | |
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437 | =item the framing protocol chosen |
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438 | |
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439 | This must be one of the framing protocols offered by the other side in the |
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440 | greeting. Each side must accept the choice of the other side. |
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441 | |
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442 | =back |
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443 | |
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444 | Example (the actual reply matching the previous example): |
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445 | |
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446 | hmac_md6_64_256;wIlLedBY956UCGSISG9mBZRDTG8xUi73/sVse2DSQp0;json |
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447 | |
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448 | =head2 DATA PHASE |
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449 | |
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450 | After this, packets get exchanged using the chosen framing protocol. It is |
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451 | quite possible that both sides use a different framing protocol. |
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452 | |
281 | =head1 SEE ALSO |
453 | =head1 SEE ALSO |
282 | |
454 | |
283 | L<AnyEvent>. |
455 | L<AnyEvent>. |
284 | |
456 | |
285 | =head1 AUTHOR |
457 | =head1 AUTHOR |