{"id":20698748,"url":"https://github.com/christian-korneck/jetis","last_synced_at":"2025-06-22T10:32:56.221Z","repository":{"id":64307237,"uuid":"340977924","full_name":"christian-korneck/jetis","owner":"christian-korneck","description":"http proxy to throw off tls encryption for packet capture","archived":false,"fork":false,"pushed_at":"2021-04-09T19:18:19.000Z","size":8,"stargazers_count":1,"open_issues_count":0,"forks_count":0,"subscribers_count":2,"default_branch":"main","last_synced_at":"2025-06-19T16:11:40.918Z","etag":null,"topics":["https","https-proxy","packet-capture","packet-sniffer","proxy","proxy-server","sniffer","tcpdump","tls"],"latest_commit_sha":null,"homepage":"","language":"Go","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/christian-korneck.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2021-02-21T18:50:50.000Z","updated_at":"2023-07-02T21:43:48.000Z","dependencies_parsed_at":"2023-01-15T11:00:34.306Z","dependency_job_id":null,"html_url":"https://github.com/christian-korneck/jetis","commit_stats":null,"previous_names":["christian-korneck/jetis","glue-tools/jetis"],"tags_count":1,"template":false,"template_full_name":null,"purl":"pkg:github/christian-korneck/jetis","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/christian-korneck%2Fjetis","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/christian-korneck%2Fjetis/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/christian-korneck%2Fjetis/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/christian-korneck%2Fjetis/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/christian-korneck","download_url":"https://codeload.github.com/christian-korneck/jetis/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/christian-korneck%2Fjetis/sbom","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":261278605,"owners_count":23134728,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["https","https-proxy","packet-capture","packet-sniffer","proxy","proxy-server","sniffer","tcpdump","tls"],"created_at":"2024-11-17T00:26:40.501Z","updated_at":"2025-06-22T10:32:51.212Z","avatar_url":"https://github.com/christian-korneck.png","language":"Go","funding_links":[],"categories":[],"sub_categories":[],"readme":"# jetis\n\nA trivial http proxy that throws off https encryption. This allows for payload packet capture of https connections with tools like `tcpdump`.\n\n## Usage\n\nTo sniff a request to a `https://` url with `tcpdump`:\n\n- start `jetis`\n\n```\n$ jetis\nstarting proxy server on localhost:8888 ...\n```\n\n- point your http client to the http proxy `http://localhost:8888`\n- in your request replace the `https://` url you want to request with `http://` (jetis will modify it to a `https://` url in flight)\n\n```\ncurl --proxy http://localhost:8888 http://\u003curl\u003e\n```\n\n\n- sniff the traffic between client and proxy - it's unencrpyted!\n\n```\ntcpdump -i lo \"host localhost and port 8888\"\n```\n\n## Usage example\n\nLet's try to see the contents of `https://github.com/robots.txt` with `tcpdump`.\n\nIf we would run `curl https://github.com/robots.txt` and sniff with `tcpdump` on the interface we would usually only see encrypted traffic because:\n\n- this URL is https only (so tcpdump only sees encrypted traffic)\n- and the `http://...` URL returns a 301 redirect to https\n\nAs a workaround we can use `jetis` as a proxy server in between. It converts any requested `http://` URL to a `https://` URL in flight. Its proxy server port is plain http, so we can sniff the traffic between our client (`curl`) and the proxy with `tcpdump`.\n\nStart `jetis`:\n```\n$ jetis\nstarting proxy server on localhost:8888 ...\n```\n\nIn another terminal start tcpdump on the local loopback interface:\n```\ntcpdump -i lo -l -w - port 8888 | tcpflow -C -r -\n```\n\nIn another terminal we can make our curl request:\n\n\n```\ncurl --proxy http://localhost:8888 http://github.com/robots.txt\n```\n\nNote that we use a `http://` URL in our request. In the `jetis` output, we can see that it automatically modified it to `https://` before making the request against the actual server:\n\n```\n2021/04/09 17:15:13 📨\toriginal url: \t http://github.com/robots.txt\n2021/04/09 17:15:13 ✏️\tnew url: \t https://github.com/robots.txt\n\n```\n\nAnd therefore `tcpdump` has seen the response data in plain text:\n\n```\n\u003c...\u003e\nUser-agent: *\n\nDisallow: /*/pulse\n\u003c...\u003e\n```\n\n## Attribution\n\nThis is a quick hack on top of the great [work](https://medium.com/@mlowicki/http-s-proxy-in-golang-in-less-than-100-lines-of-code-6a51c2f2c38c) by Michał Łowicki, licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). \n\n\n\n## FAQ\n\n### what happens if I request a `https://` URL?\n\nit gets passed through, but the traffic is encrypted\n\n### are there limitations?\n\nLots. (301 redirects to https are encrypted (don't rely on `curl -L`), no http/2, no hbh headers, etc etc). This is a convenience toy tool for simple use cases. When in doubt you probably want to use a proper \"inspection\" proxy like [Charles](https://www.charlesproxy.com/).\n\n### why this name?\n\n\u003e \"to jettison (aviation): to throw off from a moving aircraft.\"","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fchristian-korneck%2Fjetis","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fchristian-korneck%2Fjetis","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fchristian-korneck%2Fjetis/lists"}