base on A golang implementation of endlessh exporting Prometheus metrics, visualized by a Grafana dashboard. # endlessh-go A golang implementation of [endlessh](https://nullprogram.com/blog/2019/03/22/) exporting Prometheus metrics, visualized by a Grafana dashboard.  ## Introduction [Endlessh](https://nullprogram.com/blog/2019/03/22/) is a great idea that not only blocks the brute force SSH attacks, but also wastes attackers time as a kind of counter-attack. Besides trapping the attackers, I also want to visualize the Geolocations and other statistics of the sources of attacks. Unfortunately the wonderful original [C implementation of endlessh](https://github.com/skeeto/endlessh) only provides text based log, but I do not like the solution that writes extra scripts to parse the log outputs, then exports the results to a dashboard, because it would introduce extra layers in my current setup and it would depend on the format of the text log file rather than some structured data. Thus I create this golang implementation of endlessh to export [Prometheus](https://prometheus.io/) metrics and a [Grafana](https://grafana.com/) dashboard to visualize them. If you want a dashboard of sources of attacks and do not mind the endlessh server, besides trapping the attackers, does extra things including: translating IP to Geohash, exporting Prometheus metrics, and using more memory (about 10MB), this is the solution for you. ## Getting Started Clone the repo then build from source: ``` go build . ./endlessh-go & ``` Alternatively, you can use the [docker image](https://hub.docker.com/r/shizunge/endlessh-go): ``` docker run -d -p 2222:2222 shizunge/endlessh-go -logtostderr -v=1 ``` It listens to port `2222` by default. Then you can try to connect to the endlessh server. Your SSH client should hang there. ``` ssh -p 2222 localhost ``` If you want log like the [C implementation](https://github.com/skeeto/endlessh), you need to set both CLI arguments `-logtostderr` and `-v=1`, then the log will go to stderr. You can set different log destinations via CLI arguments. Also check out [examples](./examples/README.md) for the setup of the full stack. ## Usage `./endlessh-go --help` ``` Usage of ./endlessh-go -alsologtostderr log to standard error as well as files -conn_type string Connection type. Possible values are tcp, tcp4, tcp6 (default "tcp") -enable_prometheus Enable prometheus -geoip_supplier string Supplier to obtain Geohash of IPs. Possible values are "off", "ip-api", "max-mind-db" (default "off") -host string SSH listening address (default "0.0.0.0") -interval_ms int Message millisecond delay (default 1000) -line_length int Maximum banner line length (default 32) -log_backtrace_at value when logging hits line file:N, emit a stack trace -log_dir string If non-empty, write log files in this directory -log_link string If non-empty, add symbolic links in this directory to the log files -logbuflevel int Buffer log messages logged at this level or lower (-1 means don't buffer; 0 means buffer INFO only; ...). Has limited applicability on non-prod platforms. -logtostderr log to standard error instead of files -max_clients int Maximum number of clients (default 4096) -max_mind_db string Path to the MaxMind DB file. -port value SSH listening port. You may provide multiple -port flags to listen to multiple ports. (default "2222") -prometheus_clean_unseen_seconds int Remove series if the IP is not seen for the given time. Set to 0 to disable. (default 0) -prometheus_entry string Entry point for prometheus (default "metrics") -prometheus_host string The address for prometheus (default "0.0.0.0") -prometheus_port string The port for prometheus (default "2112") -stderrthreshold value logs at or above this threshold go to stderr (default 2) -v value log level for V logs -vmodule value comma-separated list of pattern=N settings for file-filtered logging ``` ## Metrics Endlessh-go exports the following Prometheus metrics. | Metric | Type | Description | |--------------------------------------|-------|--------------| | endlessh_client_open_count_total | count | Total number of clients that tried to connect to this host. | | endlessh_client_closed_count_total | count | Total number of clients that stopped connecting to this host. | | endlessh_sent_bytes_total | count | Total bytes sent to clients that tried to connect to this host. | | endlessh_trapped_time_seconds_total | count | Total seconds clients spent on endlessh. | | endlessh_client_open_count | count | Number of connections of clients. <br> Labels: <br> <ul><li> `ip`: Remote IP of the client </li> <li> `local_port`: Local port the program listens to </li> <li> `country`: Country of the IP </li> <li> `location`: Country, Region, and City </li> <li> `geohash`: Geohash of the location </li></ul> | | endlessh_client_trapped_time_seconds | count | Seconds a client spends on endlessh. <br> Labels: <br> <ul><li> `ip`: Remote IP of the client </li> <li> `local_port`: Local port the program listens to </li></ul> | The metrics is off by default, you can turn it via the CLI argument `-enable_prometheus`. It listens to port `2112` and entry point is `/metrics` by default. The port and entry point can be changed via CLI arguments. The endlessh-go server stores the geohash of attackers as a label on `endlessh_client_open_count`, which is also off by default. You can turn it on via the CLI argument `-geoip_supplier`. The endlessh-go uses service from [ip-api](https://ip-api.com/), which may enforce a query rate and limit commercial use. Visit their website for their terms and policies. You could also use an offline GeoIP database from [MaxMind](https://www.maxmind.com) by setting `-geoip_supplier` to _max-mind-db_ and `-max_mind_db` to the path of the database file. ## Dashboard The dashboard requires Grafana 8.2. You can import the dashboard from Grafana.com using ID [15156](https://grafana.com/grafana/dashboards/15156) The dashboard visualizes data for the selected time range. The IP addresses are clickable and link you to the [ARIN](https://www.arin.net/) database. ## Contacts If you have any problems or questions, please contact me through a [GitHub issue](https://github.com/shizunge/endlessh-go/issues) ", Assign "at most 3 tags" to the expected json: {"id":"8942","tags":[]} "only from the tags list I provide: [{"id":77,"name":"3d"},{"id":89,"name":"agent"},{"id":17,"name":"ai"},{"id":54,"name":"algorithm"},{"id":24,"name":"api"},{"id":44,"name":"authentication"},{"id":3,"name":"aws"},{"id":27,"name":"backend"},{"id":60,"name":"benchmark"},{"id":72,"name":"best-practices"},{"id":39,"name":"bitcoin"},{"id":37,"name":"blockchain"},{"id":1,"name":"blog"},{"id":45,"name":"bundler"},{"id":58,"name":"cache"},{"id":21,"name":"chat"},{"id":49,"name":"cicd"},{"id":4,"name":"cli"},{"id":64,"name":"cloud-native"},{"id":48,"name":"cms"},{"id":61,"name":"compiler"},{"id":68,"name":"containerization"},{"id":92,"name":"crm"},{"id":34,"name":"data"},{"id":47,"name":"database"},{"id":8,"name":"declarative-gui "},{"id":9,"name":"deploy-tool"},{"id":53,"name":"desktop-app"},{"id":6,"name":"dev-exp-lib"},{"id":59,"name":"dev-tool"},{"id":13,"name":"ecommerce"},{"id":26,"name":"editor"},{"id":66,"name":"emulator"},{"id":62,"name":"filesystem"},{"id":80,"name":"finance"},{"id":15,"name":"firmware"},{"id":73,"name":"for-fun"},{"id":2,"name":"framework"},{"id":11,"name":"frontend"},{"id":22,"name":"game"},{"id":81,"name":"game-engine "},{"id":23,"name":"graphql"},{"id":84,"name":"gui"},{"id":91,"name":"http"},{"id":5,"name":"http-client"},{"id":51,"name":"iac"},{"id":30,"name":"ide"},{"id":78,"name":"iot"},{"id":40,"name":"json"},{"id":83,"name":"julian"},{"id":38,"name":"k8s"},{"id":31,"name":"language"},{"id":10,"name":"learning-resource"},{"id":33,"name":"lib"},{"id":41,"name":"linter"},{"id":28,"name":"lms"},{"id":16,"name":"logging"},{"id":76,"name":"low-code"},{"id":90,"name":"message-queue"},{"id":42,"name":"mobile-app"},{"id":18,"name":"monitoring"},{"id":36,"name":"networking"},{"id":7,"name":"node-version"},{"id":55,"name":"nosql"},{"id":57,"name":"observability"},{"id":46,"name":"orm"},{"id":52,"name":"os"},{"id":14,"name":"parser"},{"id":74,"name":"react"},{"id":82,"name":"real-time"},{"id":56,"name":"robot"},{"id":65,"name":"runtime"},{"id":32,"name":"sdk"},{"id":71,"name":"search"},{"id":63,"name":"secrets"},{"id":25,"name":"security"},{"id":85,"name":"server"},{"id":86,"name":"serverless"},{"id":70,"name":"storage"},{"id":75,"name":"system-design"},{"id":79,"name":"terminal"},{"id":29,"name":"testing"},{"id":12,"name":"ui"},{"id":50,"name":"ux"},{"id":88,"name":"video"},{"id":20,"name":"web-app"},{"id":35,"name":"web-server"},{"id":43,"name":"webassembly"},{"id":69,"name":"workflow"},{"id":87,"name":"yaml"}]" returns me the "expected json"