SSL handshake faillure with node.js server - node.js

Question

I'm currently trying to create a secure connection with socket.io, and I really can't achieve that for now. Trying to check if my certificates are rights, I tried to create a basic https server in nodeJS.
var fs = require('fs');
var certDir = "/path/to/the/certificates/cert-test/";
require("https").createServer(
{
key : fs.readFileSync(certDir + 'srv.key'),
cert : fs.readFileSync(certDir + 'crt.pem'),
},
function(request, response){
response.writeHeader(200, {"Content-Type": "text/plain"});
response.write("Hello World!\n");
response.end();
}).listen(8082).on('clientError', function(e){
console.log(e);
});
The equivalent with http works fine, but it's impossible to make this one work. I upgraded the node version to v0.12.4, npm to 2.11.0, https is 1.0.0 (and for further enquiries, socket.io is 1.3.5). The server is on AWS , with a bitnami instance, Ubuntu 12.04.5 LTS, kernel version 3.2.0-84-virtual and OpenSSL is 1.0.1i.
I try to reach the server through https://node.foobar.com:8082 (both in my browser and with curl), but I never achieve a proper handshake.
The server detects the following errors :
[Error: 3074971392:error:1408A0C1:SSL
routines:SSL3_GET_CLIENT_HELLO:no shared
cipher:../deps/openssl/openssl/ssl/s3_srvr.c:1389: ]
[Error: 3074971392:error:140A1175:SSL
routines:SSL_BYTES_TO_CIPHER_LIST:inappropriate
fallback:../deps/openssl/openssl/ssl/ssl_lib.c:1481: ]
I tried to check the ciphers available on the server and the ones available on my computer, and there are many matches. So guys, I'm really out of ideas, and I would appreciate some help...
EDIT
output for openssl x509 -in crt.pem -inform PEM -text -noout :
Certificate:
Data:
Version: 3 (0x2)
Serial Number:
af:b7:19:35:7b:0e:87:38
Signature Algorithm: sha256WithRSAEncryption
Issuer: C=US, ST=Arizona, L=Scottsdale, O=GoDaddy.com, Inc., OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2
Validity
Not Before: Jan 6 10:11:41 2015 GMT
Not After : Jan 25 08:15:28 2016 GMT
Subject: OU=Domain Control Validated, CN=node.foobar.com
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
Public-Key: (2048 bit)
Modulus:
00:ce:93:8c:6a:0a:54:d8:b8:02:94:0d:d4:23:98:
80:98:5e:42:fb:b2:4a:f7:62:68:82:42:32:dc:6f:
5d:02:3a:b8:34:7c:9f:1c:e6:83:94:a3:1a:1e:25:
aa:58:69:4b:4d:76:8e:07:73:09:d3:6a:20:65:ad:
40:f5:a4:75:fa:51:79:af:94:1d:c3:39:c0:d4:70:
e0:f0:61:e7:26:d8:78:b8:58:7e:0e:85:22:a2:83:
09:69:85:f6:3e:b1:de:80:71:07:88:d8:9f:f9:6a:
8b:d4:ad:61:bc:c2:bb:98:6c:36:71:d8:20:3f:d1:
d4:d8:0e:91:d7:eb:42:3f:f3:98:97:fa:c4:cb:78:
04:c2:ef:12:ba:a5:cf:cd:05:44:ad:a1:cc:ff:04:
b9:e1:74:ab:09:8a:58:1b:11:e6:f9:8f:28:c2:39:
3d:71:1e:e4:e2:e4:a4:f7:45:94:04:f2:4a:fc:62:
ab:b5:9a:18:56:e8:40:4d:12:17:a7:26:07:54:db:
5b:87:99:56:9e:5c:94:28:0d:6c:29:9d:06:56:3b:
5e:c2:1f:6b:1f:6a:90:c2:97:24:77:63:32:26:f5:
25:d6:02:73:61:6b:69:20:39:a7:be:af:51:27:c5:
a5:b4:a4:1f:e2:36:fc:15:25:30:fe:08:8f:0a:12:
5f:c9
Exponent: 65537 (0x10001)
X509v3 extensions:
X509v3 Basic Constraints: critical
CA:FALSE
X509v3 Extended Key Usage:
TLS Web Server Authentication, TLS Web Client Authentication
X509v3 Key Usage: critical
Digital Signature, Key Encipherment
X509v3 CRL Distribution Points:
Full Name:
URI:http://crl.godaddy.com/gdig2s1-87.crl
X509v3 Certificate Policies:
Policy: 2.16.840.1.114413.1.7.23.1
CPS: http://certificates.godaddy.com/repository/
Authority Information Access:
OCSP - URI:http://ocsp.godaddy.com/
CA Issuers - URI:http://certificates.godaddy.com/repository/gdig2.crt
X509v3 Authority Key Identifier:
keyid:40:C2:BD:27:8E:CC:34:83:30:A2:33:D7:FB:6C:B3:F0:B4:2C:80:CE
X509v3 Subject Alternative Name:
DNS:foobar.com, DNS:www.foobar.com, DNS:www.foo.bar.com
X509v3 Subject Key Identifier:
70:FE:A0:B4:00:2E:14:98:B8:CA:BF:C8:63:A7:23:63:7C:FA:48:82
Signature Algorithm: sha256WithRSAEncryption
70:b7:dd:2b:ed:b9:7b:4e:4d:b1:13:26:7b:5d:f4:10:1f:28:
a4:b8:f5:99:4e:ee:34:56:b1:eb:06:19:d8:14:c8:28:44:fe:
63:f1:2e:58:73:c7:22:57:1a:4f:2c:00:ef:2b:f8:c6:52:09:
71:1a:68:00:35:a0:f8:df:57:c5:98:f8:43:68:ba:b5:ff:3e:
e1:a5:ad:6a:85:64:dd:40:72:d1:9d:04:61:54:cc:7c:92:c4:
b3:68:6a:77:32:1b:49:ea:6c:7e:28:c7:67:ce:1d:ed:29:49:
d6:9c:76:4d:a3:f1:a5:f5:0a:0a:92:72:7e:0a:1a:22:43:32:
18:9f:3f:fe:62:e0:57:ee:92:9d:fb:5f:bd:4b:c9:c4:1d:ba:
cb:0d:3c:b9:00:2f:79:fc:5d:cd:df:9e:d7:c9:79:3b:45:c4:
7c:ad:cb:47:6d:8e:82:cc:dd:8e:2d:86:fc:94:4b:bf:9d:8e:
37:37:90:1c:74:73:f1:93:e7:f1:c9:e3:e0:d9:5c:fb:d6:3d:
09:6b:d5:45:ab:47:d2:65:69:6c:af:81:08:35:6c:87:7f:dd:
fa:26:2e:8a:bf:4e:53:c1:70:1a:0a:e1:7f:e9:18:c5:82:f1:
90:9e:6c:29:7b:b7:cc:a3:25:3f:7f:8d:f3:b5:58:25:62:56:
64:50:43:b3
output for openssl s_client -connect node.foobar.com:8082 -tls1 -servername node.foobar.com:
CONNECTED(00000003)
3073997000:error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure:s3_pkt.c:1262:SSL alert number 40
3073997000:error:1409E0E5:SSL routines:SSL3_WRITE_BYTES:ssl handshake failure:s3_pkt.c:598:
---
no peer certificate available
---
No client certificate CA names sent
---
SSL handshake has read 7 bytes and written 0 bytes
---
New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
SSL-Session:
Protocol : TLSv1
Cipher : 0000
Session-ID:
Session-ID-ctx:
Master-Key:
Key-Arg : None
PSK identity: None
PSK identity hint: None
SRP username: None
Start Time: 1433377982
Timeout : 7200 (sec)
Verify return code: 0 (ok)
---
I tried openssl s_client -connect node.foobar.com:8082 -tls1_2 -servername node.foobar.com, and here is the answer I got :
CONNECTED(00000003)
3074009288:error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure:s3_pkt.c:1262:SSL alert number 40
3074009288:error:1409E0E5:SSL routines:SSL3_WRITE_BYTES:ssl handshake failure:s3_pkt.c:598:
---
no peer certificate available
---
No client certificate CA names sent
---
SSL handshake has read 7 bytes and written 0 bytes
---
New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
SSL-Session:
Protocol : TLSv1.2
Cipher : 0000
Session-ID:
Session-ID-ctx:
Master-Key:
Key-Arg : None
PSK identity: None
PSK identity hint: None
SRP username: None
Start Time: 1433466977
Timeout : 7200 (sec)
Verify return code: 0 (ok)
---
By the way, in order to keep the server up, it runs with the forever package (v0.14.1).
Available ciphers :
ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:SRP-DSS-AES-256-CBC-SHA:SRP-RSA-AES-256-CBC-SHA:SRP-AES-256-CBC-SHA:DHE-DSS-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA256:DHE-RSA-AES256-SHA:DHE-DSS-AES256-SHA:DHE-RSA-CAMELLIA256-SHA:DHE-DSS-CAMELLIA256-SHA:ECDH-RSA-AES256-GCM-SHA384:ECDH-ECDSA-AES256-GCM-SHA384:ECDH-RSA-AES256-SHA384:ECDH-ECDSA-AES256-SHA384:ECDH-RSA-AES256-SHA:ECDH-ECDSA-AES256-SHA:AES256-GCM-SHA384:AES256-SHA256:AES256-SHA:CAMELLIA256-SHA:PSK-AES256-CBC-SHA:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:SRP-DSS-AES-128-CBC-SHA:SRP-RSA-AES-128-CBC-SHA:SRP-AES-128-CBC-SHA:DHE-DSS-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-SHA256:DHE-DSS-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA:DHE-RSA-SEED-SHA:DHE-DSS-SEED-SHA:DHE-RSA-CAMELLIA128-SHA:DHE-DSS-CAMELLIA128-SHA:ECDH-RSA-AES128-GCM-SHA256:ECDH-ECDSA-AES128-GCM-SHA256:ECDH-RSA-AES128-SHA256:ECDH-ECDSA-AES128-SHA256:ECDH-RSA-AES128-SHA:ECDH-ECDSA-AES128-SHA:AES128-GCM-SHA256:AES128-SHA256:AES128-SHA:SEED-SHA:CAMELLIA128-SHA:IDEA-CBC-SHA:PSK-AES128-CBC-SHA:ECDHE-RSA-RC4-SHA:ECDHE-ECDSA-RC4-SHA:ECDH-RSA-RC4-SHA:ECDH-ECDSA-RC4-SHA:RC4-SHA:RC4-MD5:PSK-RC4-SHA:ECDHE-RSA-DES-CBC3-SHA:ECDHE-ECDSA-DES-CBC3-SHA:SRP-DSS-3DES-EDE-CBC-SHA:SRP-RSA-3DES-EDE-CBC-SHA:SRP-3DES-EDE-CBC-SHA:EDH-RSA-DES-CBC3-SHA:EDH-DSS-DES-CBC3-SHA:ECDH-RSA-DES-CBC3-SHA:ECDH-ECDSA-DES-CBC3-SHA:DES-CBC3-SHA:PSK-3DES-EDE-CBC-SHA:EDH-RSA-DES-CBC-SHA:EDH-DSS-DES-CBC-SHA:DES-CBC-SHA:EXP-EDH-RSA-DES-CBC-SHA:EXP-EDH-DSS-DES-CBC-SHA:EXP-DES-CBC-SHA:EXP-RC2-CBC-MD5:EXP-RC4-MD5
Output for openssl s_client -connect node.foobar.com:8082 -tls1 -cipher "ECDHE-RSA-AES256-GCM-SHA384" -servername node.foobar.com
CONNECTED(00000003)
3073722568:error:140830B5:SSL routines:SSL3_CLIENT_HELLO:no ciphers available:s3_clnt.c:757:
---
no peer certificate available
---
No client certificate CA names sent
---
SSL handshake has read 0 bytes and written 0 bytes
---
New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
SSL-Session:
Protocol : TLSv1
Cipher : 0000
Session-ID:
Session-ID-ctx:
Master-Key:
Key-Arg : None
PSK identity: None
PSK identity hint: None
SRP username: None
Start Time: 1433512430
Timeout : 7200 (sec)
Verify return code: 0 (ok)
---
By the way, as a subsidiary question, except for the http becoming a https for the request of the socket.io/socket.io.js file I have to get in order to create the connection, is there anything else I will have to change to be able to use this package on my website?
Thank you.

Answer 1

Here's what's going on.
$ openssl s_client -connect node.inkive.com:8082 -tls1 -servername node.inkive.com -cipher 'HIGH:!aNULL:!kRSA:!PSK:!SRP:!MD5:!RC4' -debug
CONNECTED(00000003)
write to 0x7fbb02c23bb0 [0x7fbb0301cc03] (220 bytes => 220 (0xDC))
0000 - 16 03 01 00 d7 01 00 00-d3 03 01 1e 9d af 6b 4b ..............kK
0010 - ea d5 6c 84 44 b0 13 c5-77 ad 3c 98 4a 50 b3 19 ..l.D...w.<.JP..
0020 - 5c 84 d4 5e ae 58 dc 76-61 f0 9f 00 00 42 c0 14 \..^.X.va....B..
0030 - c0 0a 00 39 00 38 00 37-00 36 00 88 00 87 00 86 ...9.8.7.6......
0040 - 00 85 c0 0f c0 05 c0 13-c0 09 00 33 00 32 00 31 ...........3.2.1
0050 - 00 30 00 45 00 44 00 43-00 42 c0 0e c0 04 c0 12 .0.E.D.C.B......
0060 - c0 08 00 16 00 13 00 10-00 0d c0 0d c0 03 00 ff ................
0070 - 02 01 00 00 67 00 00 00-14 00 12 00 00 0f 6e 6f ....g.........no
0080 - 64 65 2e 69 6e 6b 69 76-65 2e 63 6f 6d 00 0b 00 de.inkive.com...
0090 - 04 03 00 01 02 00 0a 00-3a 00 38 00 0e 00 0d 00 ........:.8.....
00a0 - 19 00 1c 00 0b 00 0c 00-1b 00 18 00 09 00 0a 00 ................
00b0 - 1a 00 16 00 17 00 08 00-06 00 07 00 14 00 15 00 ................
00c0 - 04 00 05 00 12 00 13 00-01 00 02 00 03 00 0f 00 ................
00d0 - 10 00 11 00 23 00 00 00-0f 00 01 01 ....#.......
read from 0x7fbb02c23bb0 [0x7fbb03018603] (5 bytes => 5 (0x5))
0000 - 15 03 01 00 02 .....
read from 0x7fbb02c23bb0 [0x7fbb03018608] (2 bytes => 2 (0x2))
0000 - 02 28 .(
140735193977308:error:14094410:SSL routines:ssl3_read_bytes:sslv3 alert handshake failure:s3_pkt.c:1461:SSL alert number 40
140735193977308:error:1409E0E5:SSL routines:ssl3_write_bytes:ssl handshake failure:s3_pkt.c:645
The read of 15 03 01 00 02 is a TLS Record. Its what carries the TLS payload. The 03 01 is the TLS version. The 00 02 is the length of the payload.
The next two bytes are the payload, which is the alert. 02 is the alert, and 28 is the alert number, which is 40.
Alert 40 is Handshake Failure. According to RFC 5246 it is sent:
7.4.1.3. Server Hello
When this message will be sent:
The server will send this message in response to a ClientHello
message when it was able to find an acceptable set of algorithms.
If it cannot find such a match, it will respond with a handshake
failure alert.
I hate to answer a question with a question, but what protocols and cipher suites are enabled at the server?
Related, the node.js docs create a HTTPS server like this:
var https = require('https');
var fs = require('fs');
var options = {
key: fs.readFileSync('/path/to/the/certificates/cert-test/srv.key'),
cert: fs.readFileSync('/path/to/the/certificates/cert-test/crt.pem'),
};
https.createServer(options, function (req, res) {
res.writeHead(200);
res.end("hello world\n");
}).listen(8082);
You should probably try it since its the official way to create one. The function(request, response){...}).listen(8082) looks odd to me.
From the Edit:
Available ciphers :
ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-SHA384:...
... EXP-EDH-DSS-DES-CBC-SHA:EXP-DES-CBC-SHA:EXP-RC2-CBC-MD5:EXP-RC4-MD5
Use "HIGH:!aNULL:!kRSA:!MD5:!RC4:!PSK:!SRP:!DSS:!DSA". It will get you Integer and Elliptic Curve Diffie-Hellman, and avoid the Obsolete Cryptography Warnings in browsers.
Also, don't enable SRP and PSK unless you are actually using them. Don't enable DSS unless you have a DSS/DSA key. And you need aNULL because anonymous protocols are enabled by default in OpenSSL. And don't enable those export grade cipher suites (EXP). And don't enable MEDIUM or LOW for that matter. All modern user agents have no trouble with HIGH.
Using the string above, here are the ciphers you are enabling:
$ openssl ciphers -v 'HIGH:!aNULL:!kRSA:!MD5:!RC4:!PSK:!SRP:!DSS:!DSA'
ECDHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(256) Mac=AEAD
ECDHE-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESGCM(256) Mac=AEAD
ECDHE-RSA-AES256-SHA384 TLSv1.2 Kx=ECDH Au=RSA Enc=AES(256) Mac=SHA384
ECDHE-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA384
ECDHE-RSA-AES256-SHA SSLv3 Kx=ECDH Au=RSA Enc=AES(256) Mac=SHA1
ECDHE-ECDSA-AES256-SHA SSLv3 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA1
DH-DSS-AES256-GCM-SHA384 TLSv1.2 Kx=DH/DSS Au=DH Enc=AESGCM(256) Mac=AEAD
DH-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH/RSA Au=DH Enc=AESGCM(256) Mac=AEAD
DHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(256) Mac=AEAD
DHE-RSA-AES256-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AES(256) Mac=SHA256
DH-RSA-AES256-SHA256 TLSv1.2 Kx=DH/RSA Au=DH Enc=AES(256) Mac=SHA256
DH-DSS-AES256-SHA256 TLSv1.2 Kx=DH/DSS Au=DH Enc=AES(256) Mac=SHA256
DHE-RSA-AES256-SHA SSLv3 Kx=DH Au=RSA Enc=AES(256) Mac=SHA1
DH-RSA-AES256-SHA SSLv3 Kx=DH/RSA Au=DH Enc=AES(256) Mac=SHA1
DH-DSS-AES256-SHA SSLv3 Kx=DH/DSS Au=DH Enc=AES(256) Mac=SHA1
DHE-RSA-CAMELLIA256-SHA SSLv3 Kx=DH Au=RSA Enc=Camellia(256) Mac=SHA1
DH-RSA-CAMELLIA256-SHA SSLv3 Kx=DH/RSA Au=DH Enc=Camellia(256) Mac=SHA1
DH-DSS-CAMELLIA256-SHA SSLv3 Kx=DH/DSS Au=DH Enc=Camellia(256) Mac=SHA1
ECDH-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH/RSA Au=ECDH Enc=AESGCM(256) Mac=AEAD
ECDH-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AESGCM(256) Mac=AEAD
ECDH-RSA-AES256-SHA384 TLSv1.2 Kx=ECDH/RSA Au=ECDH Enc=AES(256) Mac=SHA384
ECDH-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AES(256) Mac=SHA384
ECDH-RSA-AES256-SHA SSLv3 Kx=ECDH/RSA Au=ECDH Enc=AES(256) Mac=SHA1
ECDH-ECDSA-AES256-SHA SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=AES(256) Mac=SHA1
ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(128) Mac=AEAD
ECDHE-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESGCM(128) Mac=AEAD
ECDHE-RSA-AES128-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AES(128) Mac=SHA256
ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA256
ECDHE-RSA-AES128-SHA SSLv3 Kx=ECDH Au=RSA Enc=AES(128) Mac=SHA1
ECDHE-ECDSA-AES128-SHA SSLv3 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA1
DH-DSS-AES128-GCM-SHA256 TLSv1.2 Kx=DH/DSS Au=DH Enc=AESGCM(128) Mac=AEAD
DH-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH/RSA Au=DH Enc=AESGCM(128) Mac=AEAD
DHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(128) Mac=AEAD
DHE-RSA-AES128-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AES(128) Mac=SHA256
DH-RSA-AES128-SHA256 TLSv1.2 Kx=DH/RSA Au=DH Enc=AES(128) Mac=SHA256
DH-DSS-AES128-SHA256 TLSv1.2 Kx=DH/DSS Au=DH Enc=AES(128) Mac=SHA256
DHE-RSA-AES128-SHA SSLv3 Kx=DH Au=RSA Enc=AES(128) Mac=SHA1
DH-RSA-AES128-SHA SSLv3 Kx=DH/RSA Au=DH Enc=AES(128) Mac=SHA1
DH-DSS-AES128-SHA SSLv3 Kx=DH/DSS Au=DH Enc=AES(128) Mac=SHA1
DHE-RSA-CAMELLIA128-SHA SSLv3 Kx=DH Au=RSA Enc=Camellia(128) Mac=SHA1
DH-RSA-CAMELLIA128-SHA SSLv3 Kx=DH/RSA Au=DH Enc=Camellia(128) Mac=SHA1
DH-DSS-CAMELLIA128-SHA SSLv3 Kx=DH/DSS Au=DH Enc=Camellia(128) Mac=SHA1
ECDH-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH/RSA Au=ECDH Enc=AESGCM(128) Mac=AEAD
ECDH-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AESGCM(128) Mac=AEAD
ECDH-RSA-AES128-SHA256 TLSv1.2 Kx=ECDH/RSA Au=ECDH Enc=AES(128) Mac=SHA256
ECDH-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AES(128) Mac=SHA256
ECDH-RSA-AES128-SHA SSLv3 Kx=ECDH/RSA Au=ECDH Enc=AES(128) Mac=SHA1
ECDH-ECDSA-AES128-SHA SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=AES(128) Mac=SHA1
ECDHE-RSA-DES-CBC3-SHA SSLv3 Kx=ECDH Au=RSA Enc=3DES(168) Mac=SHA1
ECDHE-ECDSA-DES-CBC3-SHA SSLv3 Kx=ECDH Au=ECDSA Enc=3DES(168) Mac=SHA1
EDH-RSA-DES-CBC3-SHA SSLv3 Kx=DH Au=RSA Enc=3DES(168) Mac=SHA1
DH-RSA-DES-CBC3-SHA SSLv3 Kx=DH/RSA Au=DH Enc=3DES(168) Mac=SHA1
DH-DSS-DES-CBC3-SHA SSLv3 Kx=DH/DSS Au=DH Enc=3DES(168) Mac=SHA1
ECDH-RSA-DES-CBC3-SHA SSLv3 Kx=ECDH/RSA Au=ECDH Enc=3DES(168) Mac=SHA1
ECDH-ECDSA-DES-CBC3-SHA SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=3DES(168) Mac=SHA1

Answer 2

just want to remind you that there is no response.writeHeader() method, it should be response.writeHead().
ref:https://nodejs.org/api/http.html#http_response_writehead_statuscode_statusmessage_headers

Answer 3

If the client isn't affected, you might want to do
const tls = require('tls')
tls.DEFAULT_ECDH_CURVE = 'auto'
somewhere, for example in server.js (your file).
This will only affect the server module and not go to the client at all.
Regarding security, as far as I understood the 8.x.x release accidentally shipped a strict setting for curves (but not the most secure one), and they can't change the default until 10.x.x because of LTS/semver reasons.
In 10.x.x it is 'auto' so I doubt that's a very insecure option.