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@@ -1,10 +1,30 @@
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# smtp-proxy
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-Simple Go SMTP relay/proxy server that accepts mails via SMTP
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-and forwards directly to another SMTP server.
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+Simple Golang based SMTP relay/proxy server that accepts mail via SMTP
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+and forwards it directly to another SMTP server.
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+
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+
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+## Why another SMTP server?
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+
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+Outgoing mails are usually send via SMTP to an MTA (Mail Transfer Agent)
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+which is one of Postfix, Exim, Sendmail or OpenSMTPD on UNIX/Linux in most
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+cases. You really don't want to setup and maintain any of those full blown
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+kitchensinks yourself because they are complex, fragile and hard to
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+configure.
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+
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+My use case is simple. I need to send automatically generated mails from
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+cron via msmtp/sSMTP/dma, mails from various services and network printers
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+to GMail without giving away my GMail credentials to each device which
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+produces mail.
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+
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## Main features
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-* STARTTLS/TLS support
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+* Supports incoming SMTPS/TLS (465), STARTTLS (587) and unencrypted SMTP (25)
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+* Checks for sender, receiver, client IP
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+* Authentication support with file (LOGIN, PLAIN)
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+* Enforce encryption for authentication
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+* Supports outgoing STARTTLS (587) and unencrypted SMTP (25)
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+* Forwards all mail to a smarthost (GMail, MailGun or any other SMTP server)
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+* Small codebase (smtp-proxy ~250 LoC, chrj/smtpd ~1200 LoC)
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* IPv6 support
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-* Forward to GMail, MailGun or any other SMTP server
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Bernhard Froehlich