Go smtpd [![GoDoc](https://godoc.org/github.com/chrj/smtpd?status.png)](https://godoc.org/github.com/chrj/smtpd) [![Go Report Card](https://goreportcard.com/badge/github.com/chrj/smtpd)](https://goreportcard.com/report/github.com/chrj/smtpd)
========

Package smtpd implements an SMTP server in golang.

Features
--------

* STARTTLS (using `crypto/tls`)
* Authentication (PLAIN/LOGIN, only after STARTTLS)
* [XCLIENT](http://www.postfix.org/XCLIENT_README.html) and [PROXY protocol](https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt) (for running behind a proxy)
* Connection, HELO, sender and recipient checks for rejecting e-mails using callbacks
* Configurable limits for: connection count, message size and recipient count
* Hands incoming e-mail off to a configured callback function

Version numbers
---------------

The package is tagged with semantic version numbers, making it suitable for use in a [Go Module](https://github.com/golang/go/wiki/Modules). 

Feedback
--------

If you end up using this package or have any feedback, I'd very much like to hear about it. You can reach me by [email](mailto:christian@technobabble.dk).


Announcing our $40M Series B led by Abstract Ventures

github.com/jonathonreinhart/smtpd

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Bad semver

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Bad dependency semver

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Bidirectional unicode control characters

This package has multiple bin scripts with the same name. This can cause non-deterministic behavior when installing or could be a sign of a supply chain attack.

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Bin script confusion

Semantic versions published out of chronological order.

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Chronological version anomaly

Project maintainer's SSH key has been compromised.

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Compromised SSH key

(Experimental) Copyleft license information was found.

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Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

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Title

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High CVE

Uses debug, reflection and dynamic code execution features.

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Debug access

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Deprecated

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Deprecated SPDX exception

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Deprecated license

Package name is similar to other popular packages and may not be the package you want.

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Possible typosquat attack

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Dynamic require

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Empty package

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High entropy strings

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Unicode homoglyphs

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HTTP dependency

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Install scripts

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Invisible chars

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Long strings

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Major refactor

This package is malware. We have asked the package registry to remove it.

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Known malware

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The package was published by an npm account that no longer exists.

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Modified license exception

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Modified license

What is network access?

Network access

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github.com/jonathonreinhart/smtpd

Features

Version numbers

Feedback

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