REPRODUCIBILITY (% or how often): always
HARDWARE (Jolla1, Tablet, XA2,…): Xperia X, Gemini
UI LANGUAGE: German
REGRESSION: (compared to previous public release: Yes, No, ?): No
When sending emails in a IPv6 network, the Mail app sends the IP address in a wrong format during EHLO to the SMTP server. Therefore most SMTP servers will refuse to accept those emails. Sending emails fails.
- IPv6 network
- SMTP server that does basic checks on the EHLO fields
STEPS TO REPRODUCE:
- Send email in Mail app
Email gets send
Email does not get send
When connecting to the SMTP server, the Mail app sends the following EHLO (excerpt of Posfix error log):
Apr 15 17:25:20 router postfix/smtpd: NOQUEUE: reject: EHLO from unknown[2a03:2260:116:0:2a3f:69ff:fecd:446]: 501 5.5.2 <[2a03:2260:116:0:2a3f:69ff:fecd:446]>: Helo command rejected: invalid ip address; proto=SMTP helo=<[2a03:2260:116:0:2a3f:69ff:fecd:446]>
The format of the IPv6 address is wrong.
Instead of “helo=<[2a03:2260:116:0:2a3f:69ff:fecd:446]>” it must be “helo=<[IPv6:2a03:2260:116:0:2a3f:69ff:fecd:446]>” - note the “IPv6:” before the IP address.
See RFC 2821, chapter 4.1.3