hello-tls 0.1.1

Create TLS Client Hello messages and scan server capabilities

Hello TLS!

This is a pure Python, single-file, dependency-less implementation of SSL/TLS Client Hello and basic scaning.

Its purpose is to quickly discover what cipher suites and SSL/TLS protocols are enabled on a server. Since the server doesn't advertise this list, instead picking from what is offered by the client, hello_tls.py sends a sequence of Client Hello with different cipher suite and protocol combinations. It usually needs less than 8 requests and 300 ms, but for servers with many cipher suites or high latency, bumping max_workers splits discovery over many threads.

There's no actual cryptography, just sending a stream of bytes and seeing if the server reply vaguely looks ok or not. Supports TLS 1.3, TLS 1.2, TLS 1.1, TLS 1.0, and maybe SSLv3 (untested). Optionally, the certificate chain can be fetched and parsed, at the cost of relying on pyOpenSSL.

def scan_server(
    server_name: str,
    port: int = 443,
    fetch_certificate_chain: bool = True,
    max_workers: int = 5,
    timeout_in_seconds: float | None = DEFAULT_TIMEOUT
    ) -> ServerScanResult:
    ...

scan_server('google.com')
# ServerScanResult(
#     certificate_chain=[Certificate(...)],
#     protocol_support={'SSLv3': False, 'TLS_1_0': True, 'TLS_1_1': True, 'TLS_1_2': True, 'TLS_1_3': True},
#     cipher_suites_tls_1_2=[CipherSuite.TLS_RSA_WITH_AES_256_GCM_SHA384, ...],
#     cipher_suites_tls_1_3=[CipherSuite.TLS_AES_256_GCM_SHA384, ...],
# )

or, as CLI that print JSON:

$ python hello_tls.py google.com
{
  "protocol_support": {
    "SSLv3": false,
    "TLS_1_0": true,
    "TLS_1_1": true,
    "TLS_1_2": true,
    "TLS_1_3": true
  },
  "cipher_suites_tls_1_2": [
    "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256",
    "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
    "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA",
    "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
    "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA",
    "TLS_RSA_WITH_AES_128_GCM_SHA256",
    "TLS_RSA_WITH_AES_128_CBC_SHA",
    "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
    "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA",
    "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
    "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256",
    "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA",
    "TLS_RSA_WITH_AES_256_GCM_SHA384",
    "TLS_RSA_WITH_AES_256_CBC_SHA",
    "TLS_RSA_WITH_3DES_EDE_CBC_SHA"
  ],
  "cipher_suites_tls_1_3": [
    "TLS_AES_256_GCM_SHA384",
    "TLS_AES_128_GCM_SHA256",
    "TLS_CHACHA20_POLY1305_SHA256"
  ],
  "certificate_chain": [
    {
      "serial_number": 264635363111603634211880343082321729508,
      "subject": {
        "CN": "*.google.com"
      },
      "issuer": {
        "C": "US",
        "O": "Google Trust Services LLC",
        "CN": "GTS CA 1C3"
      },
      "not_before": "2023-09-28T05:26:21",
      "not_after": "2023-12-21T05:26:20",
      "signature_algorithm": "sha256WithRSAEncryption",
      "extensions": {
        "keyUsage": "Digital Signature",
        "extendedKeyUsage": "TLS Web Server Authentication",
        "basicConstraints": "CA:FALSE",
        "subjectKeyIdentifier": "5C:11:A8:72:02:50:45:DC:4F:08:A5:CD:0D:FA:EC:A7:35:B2:43:DE",
        "authorityKeyIdentifier": "8A:74:7F:AF:85:CD:EE:95:CD:3D:9C:D0:E2:46:14:F3:71:35:1D:27",
        "authorityInfoAccess": "OCSP - URI:http://ocsp.pki.goog/gts1c3\nCA Issuers - URI:http://pki.goog/repo/certs/gts1c3.der",
        "subjectAltName": "DNS:*.google.com, DNS:*.appengine.google.com, DNS:*.bdn.dev, DNS:*.origin-test.bdn.dev, DNS:*.cloud.google.com, DNS:*.crowdsource.google.com, DNS:*.datacompute.google.com, DNS:*.google.ca, DNS:*.google.cl, DNS:*.google.co.in, DNS:*.google.co.jp, DNS:*.google.co.uk, DNS:*.google.com.ar, DNS:*.google.com.au, DNS:*.google.com.br, DNS:*.google.com.co, DNS:*.google.com.mx, DNS:*.google.com.tr, DNS:*.google.com.vn, DNS:*.google.de, DNS:*.google.es, DNS:*.google.fr, DNS:*.google.hu, DNS:*.google.it, DNS:*.google.nl, DNS:*.google.pl, DNS:*.google.pt, DNS:*.googleadapis.com, DNS:*.googleapis.cn, DNS:*.googlevideo.com, DNS:*.gstatic.cn, DNS:*.gstatic-cn.com, DNS:googlecnapps.cn, DNS:*.googlecnapps.cn, DNS:googleapps-cn.com, DNS:*.googleapps-cn.com, DNS:gkecnapps.cn, DNS:*.gkecnapps.cn, DNS:googledownloads.cn, DNS:*.googledownloads.cn, DNS:recaptcha.net.cn, DNS:*.recaptcha.net.cn, DNS:recaptcha-cn.net, DNS:*.recaptcha-cn.net, DNS:widevine.cn, DNS:*.widevine.cn, DNS:ampproject.org.cn, DNS:*.ampproject.org.cn, DNS:ampproject.net.cn, DNS:*.ampproject.net.cn, DNS:google-analytics-cn.com, DNS:*.google-analytics-cn.com, DNS:googleadservices-cn.com, DNS:*.googleadservices-cn.com, DNS:googlevads-cn.com, DNS:*.googlevads-cn.com, DNS:googleapis-cn.com, DNS:*.googleapis-cn.com, DNS:googleoptimize-cn.com, DNS:*.googleoptimize-cn.com, DNS:doubleclick-cn.net, DNS:*.doubleclick-cn.net, DNS:*.fls.doubleclick-cn.net, DNS:*.g.doubleclick-cn.net, DNS:doubleclick.cn, DNS:*.doubleclick.cn, DNS:*.fls.doubleclick.cn, DNS:*.g.doubleclick.cn, DNS:dartsearch-cn.net, DNS:*.dartsearch-cn.net, DNS:googletraveladservices-cn.com, DNS:*.googletraveladservices-cn.com, DNS:googletagservices-cn.com, DNS:*.googletagservices-cn.com, DNS:googletagmanager-cn.com, DNS:*.googletagmanager-cn.com, DNS:googlesyndication-cn.com, DNS:*.googlesyndication-cn.com, DNS:*.safeframe.googlesyndication-cn.com, DNS:app-measurement-cn.com, DNS:*.app-measurement-cn.com, DNS:gvt1-cn.com, DNS:*.gvt1-cn.com, DNS:gvt2-cn.com, DNS:*.gvt2-cn.com, DNS:2mdn-cn.net, DNS:*.2mdn-cn.net, DNS:googleflights-cn.net, DNS:*.googleflights-cn.net, DNS:admob-cn.com, DNS:*.admob-cn.com, DNS:googlesandbox-cn.com, DNS:*.googlesandbox-cn.com, DNS:*.safenup.googlesandbox-cn.com, DNS:*.gstatic.com, DNS:*.metric.gstatic.com, DNS:*.gvt1.com, DNS:*.gcpcdn.gvt1.com, DNS:*.gvt2.com, DNS:*.gcp.gvt2.com, DNS:*.url.google.com, DNS:*.youtube-nocookie.com, DNS:*.ytimg.com, DNS:android.com, DNS:*.android.com, DNS:*.flash.android.com, DNS:g.cn, DNS:*.g.cn, DNS:g.co, DNS:*.g.co, DNS:goo.gl, DNS:www.goo.gl, DNS:google-analytics.com, DNS:*.google-analytics.com, DNS:google.com, DNS:googlecommerce.com, DNS:*.googlecommerce.com, DNS:ggpht.cn, DNS:*.ggpht.cn, DNS:urchin.com, DNS:*.urchin.com, DNS:youtu.be, DNS:youtube.com, DNS:*.youtube.com, DNS:youtubeeducation.com, DNS:*.youtubeeducation.com, DNS:youtubekids.com, DNS:*.youtubekids.com, DNS:yt.be, DNS:*.yt.be, DNS:android.clients.google.com, DNS:developer.android.google.cn, DNS:developers.android.google.cn, DNS:source.android.google.cn",
        "certificatePolicies": "Policy: 2.23.140.1.2.1\nPolicy: 1.3.6.1.4.1.11129.2.5.3",
        "crlDistributionPoints": "Full Name:\n  URI:http://crls.pki.goog/gts1c3/QOvJ0N1sT2A.crl",
        "ct_precert_scts": "Signed Certificate Timestamp:\n    Version   : v1 (0x0)\n    Log ID    : 7A:32:8C:54:D8:B7:2D:B6:20:EA:38:E0:52:1E:E9:84:\n                16:70:32:13:85:4D:3B:D2:2B:C1:3A:57:A3:52:EB:52\n    Timestamp : Sep 28 06:26:23.210 2023 GMT\n    Extensions: none\n    Signature : ecdsa-with-SHA256\n                30:45:02:21:00:D6:B7:8E:9F:C0:72:04:FE:61:22:A1:\n                62:19:1E:58:1C:1B:C6:3C:44:8F:95:FE:C2:C3:7F:B9:\n                91:04:2A:CB:1A:02:20:35:E3:19:C2:F6:3A:E1:7E:1D:\n                93:65:3E:FF:32:32:C9:39:43:98:47:2D:9D:25:C6:E0:\n                A4:92:AE:6E:E5:F0:AD\nSigned Certificate Timestamp:\n    Version   : v1 (0x0)\n    Log ID    : E8:3E:D0:DA:3E:F5:06:35:32:E7:57:28:BC:89:6B:C9:\n                03:D3:CB:D1:11:6B:EC:EB:69:E1:77:7D:6D:06:BD:6E\n    Timestamp : Sep 28 06:26:23.163 2023 GMT\n    Extensions: none\n    Signature : ecdsa-with-SHA256\n                30:45:02:21:00:D3:C4:84:79:A4:9B:B2:23:5B:3E:84:\n                73:56:5D:57:58:C5:C1:53:4D:F5:C7:A5:4D:CB:1F:9F:\n                34:D6:36:30:F3:02:20:38:5F:05:11:CB:53:7E:B8:D6:\n                C4:BF:7D:5E:E2:FF:81:25:E9:9D:1C:22:63:A7:47:4D:\n                BE:9B:0C:7B:C5:DF:07"
      }
    },
    {
      "serial_number": 159612451717983579589660725350,
      "subject": {
        "C": "US",
        "O": "Google Trust Services LLC",
        "CN": "GTS CA 1C3"
      },
      "issuer": {
        "C": "US",
        "O": "Google Trust Services LLC",
        "CN": "GTS Root R1"
      },
      "not_before": "2020-08-13T00:00:42",
      "not_after": "2027-09-30T00:00:42",
      "signature_algorithm": "sha256WithRSAEncryption",
      "extensions": {
        "keyUsage": "Digital Signature, Certificate Sign, CRL Sign",
        "extendedKeyUsage": "TLS Web Server Authentication, TLS Web Client Authentication",
        "basicConstraints": "CA:TRUE, pathlen:0",
        "subjectKeyIdentifier": "8A:74:7F:AF:85:CD:EE:95:CD:3D:9C:D0:E2:46:14:F3:71:35:1D:27",
        "authorityKeyIdentifier": "E4:AF:2B:26:71:1A:2B:48:27:85:2F:52:66:2C:EF:F0:89:13:71:3E",
        "authorityInfoAccess": "OCSP - URI:http://ocsp.pki.goog/gtsr1\nCA Issuers - URI:http://pki.goog/repo/certs/gtsr1.der",
        "crlDistributionPoints": "Full Name:\n  URI:http://crl.pki.goog/gtsr1/gtsr1.crl",
        "certificatePolicies": "Policy: 1.3.6.1.4.1.11129.2.5.3\n  CPS: https://pki.goog/repository/\nPolicy: 2.23.140.1.2.1\nPolicy: 2.23.140.1.2.2"
      }
    },
    {
      "serial_number": 159159747900478145820483398898491642637,
      "subject": {
        "C": "US",
        "O": "Google Trust Services LLC",
        "CN": "GTS Root R1"
      },
      "issuer": {
        "C": "BE",
        "O": "GlobalSign nv-sa",
        "OU": "Root CA",
        "CN": "GlobalSign Root CA"
      },
      "not_before": "2020-06-19T00:00:42",
      "not_after": "2028-01-28T00:00:42",
      "signature_algorithm": "sha256WithRSAEncryption",
      "extensions": {
        "keyUsage": "Digital Signature, Certificate Sign, CRL Sign",
        "basicConstraints": "CA:TRUE",
        "subjectKeyIdentifier": "E4:AF:2B:26:71:1A:2B:48:27:85:2F:52:66:2C:EF:F0:89:13:71:3E",
        "authorityKeyIdentifier": "60:7B:66:1A:45:0D:97:CA:89:50:2F:7D:04:CD:34:A8:FF:FC:FD:4B",
        "authorityInfoAccess": "OCSP - URI:http://ocsp.pki.goog/gsr1\nCA Issuers - URI:http://pki.goog/gsr1/gsr1.crt",
        "crlDistributionPoints": "Full Name:\n  URI:http://crl.pki.goog/gsr1/gsr1.crl",
        "certificatePolicies": "Policy: 2.23.140.1.2.1\nPolicy: 2.23.140.1.2.2\nPolicy: 1.3.6.1.4.1.11129.2.5.3.2\nPolicy: 1.3.6.1.4.1.11129.2.5.3.3"
      }
    }
  ]
}