crypto/tls: support renegotiation extension.

The renegotiation extension was introduced[1] due to an attack by Ray in
which a client's handshake was spliced into a connection that was
renegotiating, thus giving an attacker the ability to inject an
arbitary prefix into the connection.

Go has never supported renegotiation as a server and so this attack
doesn't apply. As a client, it's possible that at some point in the
future the population of servers will be sufficiently updated that
it'll be possible to reject connections where the server hasn't
demonstrated that it has been updated to address this problem.

We're not at that point yet, but it's good for Go servers to support
the extension so that it might be possible to do in the future.

[1] https://tools.ietf.org/search/rfc5746

R=golang-codereviews, mikioh.mikioh
CC=golang-codereviews
https://golang.org/cl/48580043

1 files changed, 64 insertions, 63 deletions

diff --git a/src/pkg/crypto/tls/testdata/Client-TLSv10-RSA-RC4 b/src/pkg/crypto/tls/testdata/Client-TLSv10-RSA-RC4
index a691255747..1a6c42c145 100644
--- a/src/pkg/crypto/tls/testdata/Client-TLSv10-RSA-RC4
+++ b/src/pkg/crypto/tls/testdata/Client-TLSv10-RSA-RC4
@@ -1,63 +1,64 @@
 >>> Flow 1 (client to server)
-00000000  16 03 01 00 70 01 00 00  6c 03 03 00 00 00 00 00  |....p...l.......|
+00000000  16 03 01 00 75 01 00 00  71 03 03 00 00 00 00 00  |....u...q.......|
 00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
 00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 1a c0 2f  |.............../|
 00000030  c0 2b c0 11 c0 07 c0 13  c0 09 c0 14 c0 0a 00 05  |.+..............|
-00000040  00 2f 00 35 c0 12 00 0a  01 00 00 29 00 05 00 05  |./.5.......)....|
+00000040  00 2f 00 35 c0 12 00 0a  01 00 00 2e 00 05 00 05  |./.5............|
 00000050  01 00 00 00 00 00 0a 00  08 00 06 00 17 00 18 00  |................|
 00000060  19 00 0b 00 02 01 00 00  0d 00 0a 00 08 04 01 04  |................|
-00000070  03 02 01 02 03                                    |.....|
+00000070  03 02 01 02 03 ff 01 00  01 00                    |..........|
 >>> Flow 2 (server to client)
-00000000  16 03 01 00 4a 02 00 00  46 03 01 52 ac 77 f7 17  |....J...F..R.w..|
-00000010  4c 25 27 29 1a fe 71 9e  69 96 e9 a7 8a 5f dc 47  |L%')..q.i...._.G|
-00000020  b1 70 9a 23 e0 3a 32 95  4e 73 a4 20 b1 7a f0 69  |.p.#.:2.Ns. .z.i|
-00000030  f6 26 55 0b 6b 77 cc b6  f2 03 5b 6c 81 25 28 ea  |.&U.kw....[l.%(.|
-00000040  4b 2e ac 7a fe 54 62 bf  62 b4 0c e3 00 05 00 16  |K..z.Tb.b.......|
-00000050  03 01 02 be 0b 00 02 ba  00 02 b7 00 02 b4 30 82  |..............0.|
-00000060  02 b0 30 82 02 19 a0 03  02 01 02 02 09 00 85 b0  |..0.............|
-00000070  bb a4 8a 7f b8 ca 30 0d  06 09 2a 86 48 86 f7 0d  |......0...*.H...|
-00000080  01 01 05 05 00 30 45 31  0b 30 09 06 03 55 04 06  |.....0E1.0...U..|
-00000090  13 02 41 55 31 13 30 11  06 03 55 04 08 13 0a 53  |..AU1.0...U....S|
-000000a0  6f 6d 65 2d 53 74 61 74  65 31 21 30 1f 06 03 55  |ome-State1!0...U|
-000000b0  04 0a 13 18 49 6e 74 65  72 6e 65 74 20 57 69 64  |....Internet Wid|
-000000c0  67 69 74 73 20 50 74 79  20 4c 74 64 30 1e 17 0d  |gits Pty Ltd0...|
-000000d0  31 30 30 34 32 34 30 39  30 39 33 38 5a 17 0d 31  |100424090938Z..1|
-000000e0  31 30 34 32 34 30 39 30  39 33 38 5a 30 45 31 0b  |10424090938Z0E1.|
-000000f0  30 09 06 03 55 04 06 13  02 41 55 31 13 30 11 06  |0...U....AU1.0..|
-00000100  03 55 04 08 13 0a 53 6f  6d 65 2d 53 74 61 74 65  |.U....Some-State|
-00000110  31 21 30 1f 06 03 55 04  0a 13 18 49 6e 74 65 72  |1!0...U....Inter|
-00000120  6e 65 74 20 57 69 64 67  69 74 73 20 50 74 79 20  |net Widgits Pty |
-00000130  4c 74 64 30 81 9f 30 0d  06 09 2a 86 48 86 f7 0d  |Ltd0..0...*.H...|
-00000140  01 01 01 05 00 03 81 8d  00 30 81 89 02 81 81 00  |.........0......|
-00000150  bb 79 d6 f5 17 b5 e5 bf  46 10 d0 dc 69 be e6 2b  |.y......F...i..+|
-00000160  07 43 5a d0 03 2d 8a 7a  43 85 b7 14 52 e7 a5 65  |.CZ..-.zC...R..e|
-00000170  4c 2c 78 b8 23 8c b5 b4  82 e5 de 1f 95 3b 7e 62  |L,x.#........;~b|
-00000180  a5 2c a5 33 d6 fe 12 5c  7a 56 fc f5 06 bf fa 58  |.,.3...\zV.....X|
-00000190  7b 26 3f b5 cd 04 d3 d0  c9 21 96 4a c7 f4 54 9f  |{&?......!.J..T.|
-000001a0  5a bf ef 42 71 00 fe 18  99 07 7f 7e 88 7d 7d f1  |Z..Bq......~.}}.|
-000001b0  04 39 c4 a2 2e db 51 c9  7c e3 c0 4c 3b 32 66 01  |.9....Q.|..L;2f.|
-000001c0  cf af b1 1d b8 71 9a 1d  db db 89 6b ae da 2d 79  |.....q.....k..-y|
-000001d0  02 03 01 00 01 a3 81 a7  30 81 a4 30 1d 06 03 55  |........0..0...U|
-000001e0  1d 0e 04 16 04 14 b1 ad  e2 85 5a cf cb 28 db 69  |..........Z..(.i|
-000001f0  ce 23 69 de d3 26 8e 18  88 39 30 75 06 03 55 1d  |.#i..&...90u..U.|
-00000200  23 04 6e 30 6c 80 14 b1  ad e2 85 5a cf cb 28 db  |#.n0l......Z..(.|
-00000210  69 ce 23 69 de d3 26 8e  18 88 39 a1 49 a4 47 30  |i.#i..&...9.I.G0|
-00000220  45 31 0b 30 09 06 03 55  04 06 13 02 41 55 31 13  |E1.0...U....AU1.|
-00000230  30 11 06 03 55 04 08 13  0a 53 6f 6d 65 2d 53 74  |0...U....Some-St|
-00000240  61 74 65 31 21 30 1f 06  03 55 04 0a 13 18 49 6e  |ate1!0...U....In|
-00000250  74 65 72 6e 65 74 20 57  69 64 67 69 74 73 20 50  |ternet Widgits P|
-00000260  74 79 20 4c 74 64 82 09  00 85 b0 bb a4 8a 7f b8  |ty Ltd..........|
-00000270  ca 30 0c 06 03 55 1d 13  04 05 30 03 01 01 ff 30  |.0...U....0....0|
-00000280  0d 06 09 2a 86 48 86 f7  0d 01 01 05 05 00 03 81  |...*.H..........|
-00000290  81 00 08 6c 45 24 c7 6b  b1 59 ab 0c 52 cc f2 b0  |...lE$.k.Y..R...|
-000002a0  14 d7 87 9d 7a 64 75 b5  5a 95 66 e4 c5 2b 8e ae  |....zdu.Z.f..+..|
-000002b0  12 66 1f eb 4f 38 b3 6e  60 d3 92 fd f7 41 08 b5  |.f..O8.n`....A..|
-000002c0  25 13 b1 18 7a 24 fb 30  1d ba ed 98 b9 17 ec e7  |%...z$.0........|
-000002d0  d7 31 59 db 95 d3 1d 78  ea 50 56 5c d5 82 5a 2d  |.1Y....x.PV\..Z-|
-000002e0  5a 5f 33 c4 b6 d8 c9 75  90 96 8c 0f 52 98 b5 cd  |Z_3....u....R...|
-000002f0  98 1f 89 20 5f f2 a0 1c  a3 1b 96 94 dd a9 fd 57  |... _..........W|
-00000300  e9 70 e8 26 6d 71 99 9b  26 6e 38 50 29 6c 90 a7  |.p.&mq..&n8P)l..|
-00000310  bd d9 16 03 01 00 04 0e  00 00 00                 |...........|
+00000000  16 03 01 00 51 02 00 00  4d 03 01 52 cc 57 58 d1  |....Q...M..R.WX.|
+00000010  c7 22 72 55 68 fb 69 12  2d 85 02 b7 66 93 40 d1  |."rUh.i.-...f.@.|
+00000020  2d 32 57 a8 f2 06 62 93  a0 39 b6 20 08 37 44 11  |-2W...b..9. .7D.|
+00000030  73 db 68 79 6d 98 30 f7  bf a2 9b a3 cb c0 03 cb  |s.hym.0.........|
+00000040  7f 79 e9 31 08 ce 93 17  25 6d c3 c4 00 05 00 00  |.y.1....%m......|
+00000050  05 ff 01 00 01 00 16 03  01 02 be 0b 00 02 ba 00  |................|
+00000060  02 b7 00 02 b4 30 82 02  b0 30 82 02 19 a0 03 02  |.....0...0......|
+00000070  01 02 02 09 00 85 b0 bb  a4 8a 7f b8 ca 30 0d 06  |.............0..|
+00000080  09 2a 86 48 86 f7 0d 01  01 05 05 00 30 45 31 0b  |.*.H........0E1.|
+00000090  30 09 06 03 55 04 06 13  02 41 55 31 13 30 11 06  |0...U....AU1.0..|
+000000a0  03 55 04 08 13 0a 53 6f  6d 65 2d 53 74 61 74 65  |.U....Some-State|
+000000b0  31 21 30 1f 06 03 55 04  0a 13 18 49 6e 74 65 72  |1!0...U....Inter|
+000000c0  6e 65 74 20 57 69 64 67  69 74 73 20 50 74 79 20  |net Widgits Pty |
+000000d0  4c 74 64 30 1e 17 0d 31  30 30 34 32 34 30 39 30  |Ltd0...100424090|
+000000e0  39 33 38 5a 17 0d 31 31  30 34 32 34 30 39 30 39  |938Z..1104240909|
+000000f0  33 38 5a 30 45 31 0b 30  09 06 03 55 04 06 13 02  |38Z0E1.0...U....|
+00000100  41 55 31 13 30 11 06 03  55 04 08 13 0a 53 6f 6d  |AU1.0...U....Som|
+00000110  65 2d 53 74 61 74 65 31  21 30 1f 06 03 55 04 0a  |e-State1!0...U..|
+00000120  13 18 49 6e 74 65 72 6e  65 74 20 57 69 64 67 69  |..Internet Widgi|
+00000130  74 73 20 50 74 79 20 4c  74 64 30 81 9f 30 0d 06  |ts Pty Ltd0..0..|
+00000140  09 2a 86 48 86 f7 0d 01  01 01 05 00 03 81 8d 00  |.*.H............|
+00000150  30 81 89 02 81 81 00 bb  79 d6 f5 17 b5 e5 bf 46  |0.......y......F|
+00000160  10 d0 dc 69 be e6 2b 07  43 5a d0 03 2d 8a 7a 43  |...i..+.CZ..-.zC|
+00000170  85 b7 14 52 e7 a5 65 4c  2c 78 b8 23 8c b5 b4 82  |...R..eL,x.#....|
+00000180  e5 de 1f 95 3b 7e 62 a5  2c a5 33 d6 fe 12 5c 7a  |....;~b.,.3...\z|
+00000190  56 fc f5 06 bf fa 58 7b  26 3f b5 cd 04 d3 d0 c9  |V.....X{&?......|
+000001a0  21 96 4a c7 f4 54 9f 5a  bf ef 42 71 00 fe 18 99  |!.J..T.Z..Bq....|
+000001b0  07 7f 7e 88 7d 7d f1 04  39 c4 a2 2e db 51 c9 7c  |..~.}}..9....Q.||
+000001c0  e3 c0 4c 3b 32 66 01 cf  af b1 1d b8 71 9a 1d db  |..L;2f......q...|
+000001d0  db 89 6b ae da 2d 79 02  03 01 00 01 a3 81 a7 30  |..k..-y........0|
+000001e0  81 a4 30 1d 06 03 55 1d  0e 04 16 04 14 b1 ad e2  |..0...U.........|
+000001f0  85 5a cf cb 28 db 69 ce  23 69 de d3 26 8e 18 88  |.Z..(.i.#i..&...|
+00000200  39 30 75 06 03 55 1d 23  04 6e 30 6c 80 14 b1 ad  |90u..U.#.n0l....|
+00000210  e2 85 5a cf cb 28 db 69  ce 23 69 de d3 26 8e 18  |..Z..(.i.#i..&..|
+00000220  88 39 a1 49 a4 47 30 45  31 0b 30 09 06 03 55 04  |.9.I.G0E1.0...U.|
+00000230  06 13 02 41 55 31 13 30  11 06 03 55 04 08 13 0a  |...AU1.0...U....|
+00000240  53 6f 6d 65 2d 53 74 61  74 65 31 21 30 1f 06 03  |Some-State1!0...|
+00000250  55 04 0a 13 18 49 6e 74  65 72 6e 65 74 20 57 69  |U....Internet Wi|
+00000260  64 67 69 74 73 20 50 74  79 20 4c 74 64 82 09 00  |dgits Pty Ltd...|
+00000270  85 b0 bb a4 8a 7f b8 ca  30 0c 06 03 55 1d 13 04  |........0...U...|
+00000280  05 30 03 01 01 ff 30 0d  06 09 2a 86 48 86 f7 0d  |.0....0...*.H...|
+00000290  01 01 05 05 00 03 81 81  00 08 6c 45 24 c7 6b b1  |..........lE$.k.|
+000002a0  59 ab 0c 52 cc f2 b0 14  d7 87 9d 7a 64 75 b5 5a  |Y..R.......zdu.Z|
+000002b0  95 66 e4 c5 2b 8e ae 12  66 1f eb 4f 38 b3 6e 60  |.f..+...f..O8.n`|
+000002c0  d3 92 fd f7 41 08 b5 25  13 b1 18 7a 24 fb 30 1d  |....A..%...z$.0.|
+000002d0  ba ed 98 b9 17 ec e7 d7  31 59 db 95 d3 1d 78 ea  |........1Y....x.|
+000002e0  50 56 5c d5 82 5a 2d 5a  5f 33 c4 b6 d8 c9 75 90  |PV\..Z-Z_3....u.|
+000002f0  96 8c 0f 52 98 b5 cd 98  1f 89 20 5f f2 a0 1c a3  |...R...... _....|
+00000300  1b 96 94 dd a9 fd 57 e9  70 e8 26 6d 71 99 9b 26  |......W.p.&mq..&|
+00000310  6e 38 50 29 6c 90 a7 bd  d9 16 03 01 00 04 0e 00  |n8P)l...........|
+00000320  00 00                                             |..|
 >>> Flow 3 (client to server)
 00000000  16 03 01 00 86 10 00 00  82 00 80 6d 51 f3 7f f9  |...........mQ...|
 00000010  3e fb 75 82 41 36 83 e8  6a ee 2a 2e 25 90 67 4c  |>.u.A6..j.*.%.gL|
@@ -68,15 +69,15 @@
 00000060  e6 bd 77 82 6f 23 b6 e0  bd a2 92 b7 3a ac e8 56  |..w.o#......:..V|
 00000070  f1 af 54 5e 46 87 e9 3b  33 e7 b8 28 b7 d6 c8 90  |..T^F..;3..(....|
 00000080  35 d4 1c 43 d1 30 6f 55  4e 0a 70 14 03 01 00 01  |5..C.0oUN.p.....|
-00000090  01 16 03 01 00 24 8f 42  2e 1a 6f 42 a2 d1 51 ae  |.....$.B..oB..Q.|
-000000a0  68 c4 3c 76 d0 df c3 41  3e 79 88 1a 43 28 bf 08  |h.<v...A>y..C(..|
-000000b0  ad 4e e2 1c f1 7f 87 3d  9d ba                    |.N.....=..|
+00000090  01 16 03 01 00 24 54 26  aa 7d 70 99 51 f1 bc d6  |.....$T&.}p.Q...|
+000000a0  e9 0b 4b c7 b2 02 8c ed  36 c9 7f b8 f7 82 29 3a  |..K.....6.....):|
+000000b0  0b 6a c0 b4 ef 38 3f e8  8a bf                    |.j...8?...|
 >>> Flow 4 (server to client)
-00000000  14 03 01 00 01 01 16 03  01 00 24 19 91 48 bb ae  |..........$..H..|
-00000010  63 9d 91 d8 2f 8b 97 00  b4 ae 79 06 88 a8 23 a0  |c.../.....y...#.|
-00000020  2d f4 dc 0f d9 6e c9 24  61 dd 3f 54 ec 9b 2f     |-....n.$a.?T../|
+00000000  14 03 01 00 01 01 16 03  01 00 24 9a 52 2f b1 3c  |..........$.R/.<|
+00000010  71 92 5c 81 68 a8 27 4c  b8 a9 4e 69 81 41 01 a2  |q.\.h.'L..Ni.A..|
+00000020  99 d4 0c dc 15 7b 52 b5  ee be a6 6f 70 88 91     |.....{R....op..|
 >>> Flow 5 (client to server)
-00000000  17 03 01 00 1a 80 15 48  e1 1a 02 3e 0f 11 0a 8b  |.......H...>....|
-00000010  ff 31 28 5f 7c 1e af fb  c7 c2 1f 8b fc 0f 12 15  |.1(_|...........|
-00000020  03 01 00 16 67 d2 c4 57  fd e1 55 9f 51 0d ff 89  |....g..W..U.Q...|
-00000030  09 17 87 2c 6c d4 96 9d  d9 86                    |...,l.....|
+00000000  17 03 01 00 1a b5 06 d1  18 a6 4b 26 21 47 be 14  |..........K&!G..|
+00000010  79 2e 63 49 84 1e 83 31  3b cb 97 14 94 5b 09 15  |y.cI...1;....[..|
+00000020  03 01 00 16 9d d6 d0 2a  65 f2 7e 31 20 e6 63 89  |.......*e.~1 .c.|
+00000030  b3 76 92 20 db b8 e6 25  54 1b                    |.v. ...%T.|