im running FreeSWITCH Version 1.6.14+git~20170112T174802Z~a8d53fdd79~64bit (git a8d53fd 2017-01-12 17:48:02Z 64bit)
it looks like FS brakes the from header ... pls note the extra space between the IP address and the closing ">"
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send 1009 bytes to udp/[192.168.254.168]:5060 at 15:02:13.408606:
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Via: SIP/2.0/UDP 192.168.254.73;rport;branch=z9hG4bKHr6ea76mt53QQ
Max-Forwards: 70
Call-ID: a588ad14-58f2-1235-07b5-525400e95788
CSeq: 102081187 INVITE
User-Agent: FreeSWITCH-mod_sofia/1.6.14+git~20170112T174802Z~a8d53fdd79~64bit
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
Supported: timer, path, replaces
Allow-Events: talk, hold, conference, refer
Content-Type: application/sdp
Content-Disposition: session
Content-Length: 224
X-FS-Support: update_display,send_info
v=0
o=FreeSWITCH 1484806170 1484806171 IN IP4 192.168.254.73
s=FreeSWITCH
c=IN IP4 192.168.254.73
t=0 0
m=audio 28332 RTP/AVP 8 101
a=rtpmap:8 PCMA/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
a=ptime:20
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recv 286 bytes from udp/[192.168.254.168]:5060 at 15:02:13.427078:
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SIP/2.0 400 Malformed From, fix your code!
Via: SIP/2.0/UDP 192.168.254.73;rport=5060;branch=z9hG4bKHr6ea76mt53QQ
Call-ID: a588ad14-58f2-1235-07b5-525400e95788
CSeq: 102081187 INVITE
Content-Length: 0