My stunnel.conf looks like this:
# Stunnel configuration file for Office 365 SMTP # Eric Poythress # GLOBAL OPTIONS client = yes output = stunnel-log.txt debug=7 taskbar=yes
# SERVICE-LEVEL OPTIONS [SMTP Outgoing] client = yes protocol = smtp accept = 25 connect = smtp.office365.com:587 verify = 2 CAfile = ca-certs.pem checkHost = smtp.office365.com
A larger sample of my logs looks like this:
2015.09.01 22:15:15 LOG5[1]: s_connect: connected 132.245.70.98:587 2015.09.01 22:15:15 LOG5[1]: Service [SMTP Outgoing] connected remote server from 192.168.100.41:1565 2015.09.01 22:15:15 LOG7[1]: Remote socket (FD=468) initialized 2015.09.01 22:15:15 LOG7[1]: <- 220 SN1PR15CA0037.outlook.office365.com Microsoft ESMTP MAIL Service ready at Wed, 2 Sep 2015 03:13:50 +0000 2015.09.01 22:15:15 LOG7[1]: -> 220 SN1PR15CA0037.outlook.office365.com Microsoft ESMTP MAIL Service ready at Wed, 2 Sep 2015 03:13:50 +0000 2015.09.01 22:15:15 LOG7[1]: -> EHLO localhost 2015.09.01 22:15:15 LOG7[1]: <- 250-SN1PR15CA0037.outlook.office365.com Hello [70.167.26.246] 2015.09.01 22:15:15 LOG7[1]: <- 250-SIZE 157286400 2015.09.01 22:15:15 LOG7[1]: <- 250-PIPELINING 2015.09.01 22:15:15 LOG7[1]: <- 250-DSN 2015.09.01 22:15:15 LOG7[1]: <- 250-ENHANCEDSTATUSCODES 2015.09.01 22:15:15 LOG7[1]: <- 250-STARTTLS 2015.09.01 22:15:15 LOG7[1]: <- 250-8BITMIME 2015.09.01 22:15:15 LOG7[1]: <- 250-BINARYMIME 2015.09.01 22:15:15 LOG7[1]: <- 250 CHUNKING 2015.09.01 22:15:15 LOG7[1]: -> STARTTLS 2015.09.01 22:15:16 LOG7[1]: <- 220 2.0.0 SMTP server ready 2015.09.01 22:15:16 LOG6[1]: SNI: sending servername: smtp.office365.com 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): before/connect initialization 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 write client hello A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 read server hello A 2015.09.01 22:15:16 LOG7[1]: Verification started at depth=2: C=IE, O=Baltimore, OU=CyberTrust, CN=Baltimore CyberTrust Root 2015.09.01 22:15:16 LOG7[1]: CERT: Pre-verification succeeded 2015.09.01 22:15:16 LOG6[1]: Certificate accepted at depth=2: C=IE, O=Baltimore, OU=CyberTrust, CN=Baltimore CyberTrust Root 2015.09.01 22:15:16 LOG7[1]: Verification started at depth=1: C=US, ST=Washington, L=Redmond, O=Microsoft Corporation, OU=Microsoft IT, CN=Microsoft IT SSL SHA1 2015.09.01 22:15:16 LOG7[1]: CERT: Pre-verification succeeded 2015.09.01 22:15:16 LOG6[1]: Certificate accepted at depth=1: C=US, ST=Washington, L=Redmond, O=Microsoft Corporation, OU=Microsoft IT, CN=Microsoft IT SSL SHA1 2015.09.01 22:15:16 LOG7[1]: Verification started at depth=0: C=US, ST=WA, L=Redmond, O=Microsoft Corporation, OU=Microsoft Corporation, CN=outlook.com 2015.09.01 22:15:16 LOG7[1]: CERT: Pre-verification succeeded 2015.09.01 22:15:16 LOG6[1]: CERT: Host name "smtp.office365.com" matched with "*.office365.com" 2015.09.01 22:15:16 LOG5[1]: Certificate accepted at depth=0: C=US, ST=WA, L=Redmond, O=Microsoft Corporation, OU=Microsoft Corporation, CN=outlook.com 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 read server certificate A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 read server key exchange A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 read server certificate request A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 read server done A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 write client certificate A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 write client key exchange A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 write change cipher spec A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 write finished A 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 flush data 2015.09.01 22:15:16 LOG7[1]: SSL state (connect): SSLv3 read finished A 2015.09.01 22:15:16 LOG7[1]: 2 client connect(s) requested 2015.09.01 22:15:16 LOG7[1]: 2 client connect(s) succeeded 2015.09.01 22:15:16 LOG7[1]: 0 client renegotiation(s) requested 2015.09.01 22:15:16 LOG7[1]: 0 session reuse(s) 2015.09.01 22:15:16 LOG6[1]: SSL connected: new session negotiated 2015.09.01 22:15:16 LOG7[1]: Deallocating application specific data for addr index 2015.09.01 22:15:16 LOG6[1]: Negotiated TLSv1.2 ciphersuite ECDHE-RSA-AES256-SHA384 (256-bit encryption) 2015.09.01 22:15:16 LOG7[1]: Compression: null, expansion: null 2015.09.01 22:15:21 LOG6[1]: Read socket closed (readsocket) 2015.09.01 22:15:21 LOG7[1]: Sending close_notify alert 2015.09.01 22:15:21 LOG7[1]: SSL alert (write): warning: close notify 2015.09.01 22:15:21 LOG6[1]: SSL_shutdown successfully sent close_notify alert 2015.09.01 22:15:21 LOG6[1]: SSL socket closed (SSL_read) 2015.09.01 22:15:21 LOG7[1]: Sent socket write shutdown 2015.09.01 22:15:21 LOG5[1]: Connection closed: 71 byte(s) sent to SSL, 237 byte(s) sent to socket 2015.09.01 22:15:21 LOG7[1]: Remote socket (FD=468) closed 2015.09.01 22:15:21 LOG7[1]: Local socket (FD=440) closed 2015.09.01 22:15:21 LOG7[1]: Service [SMTP Outgoing] finished (0 left)
-Eric