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email:test_smtp [2016/11/11 00:27] – peteremail:test_smtp [2019/11/27 22:15] (current) – removed peter
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-====== Email - Test SMTP ====== 
- 
-The commands used here are covered in section 4.1 of RFC 2821 [http://www.ietf.org/rfc/rfc2821.txt]. 
- 
-===== Obtain the DNS MX record for a domain ===== 
- 
-Issue the following command: 
- 
-**Linux:** 
- 
-<code bash> 
-nslookup -type=mx sharewiz.net 
- 
-Non-authoritative answer: 
-sharewiz.net      mail exchanger = 10 mail.sharewiz.net. 
- 
-Authoritative answers can be found from: 
-mail.sharewiz.net internet address = 5.42.134.35 
-</code> 
- 
- 
-**Windows:** 
- 
-<code bash> 
-nslookup -type=mx sharewiz.net 
- 
-Non-authoritative answer: 
-sharewiz.net      MX preference = 10, mail exchanger = mail.sharewiz.net. 
-</code> 
- 
- 
-===== Get the DNS PTR for the IP ===== 
- 
-This requires to know what IP address. 
- 
-With the IP address run the following command, where A.B.C.D is the IP address. 
- 
-**Linux:** 
- 
-<code bash> 
-nslookup -type=ptr A.B.C.D 
-Non-authoritative answer:  D.C.B.A.in-addr.arpa  name = server.example.com 
-</code> 
- 
-**Windows:** 
- 
-<code bash> 
-nslookup -type=ptr A.B.C.D 
-Non-authoritative answer:  D.C.B.A.in-addr.arpa  name = server.example.com 
-</code> 
- 
- 
-So now that we have the MX record for example.com and the PTR for the IP we are going to use, it is time to login to the SMTP server. 
- 
- 
-===== Connect to server ===== 
- 
-For non-secure SMTP, you can use 
- 
-<code bash> 
-telnet example.com 25 
-</code> 
- 
-For secure SMTP, you can use one of following: 
- 
-<code bash> 
-openssl s_client -starttls smtp -connect example.com:25 
-openssl s_client -starttls smtp -connect example.com:465 
-openssl s_client -starttls smtp -connect example.com:587 
-</code> 
- 
-As soon as you connect to the server, run: 
- 
-<code bash> 
-ehlo example.com 
-</code> 
- 
-You will get output like below as reply: 
- 
-<code> 
-250-test.rtcamp.com 
-250-PIPELINING 
-250-SIZE 10240000 
-250-VRFY 
-250-ETRN 
-250-STARTTLS 
-250-AUTH PLAIN LOGIN 
-250-ENHANCEDSTATUSCODES 
-250-8BITMIME 
-250 DSN 
-</code> 
- 
-If you do not see line like 250-AUTH ... line, then your server may not support authentication.  Most likely you will see this when trying with telnet or openssl without startls. 
- 
- 
-===== Authentication ===== 
- 
-For admin@example.com and password, generate base64 encoded string like below: 
- 
-<code bash> 
-echo -ne '\0admin@example.com\0password' | base64 
-</code> 
- 
-Please note use of **\0** before username and password.  It must be used as it is.  Also, use single-quotes to avoid escaping special characters in your password. 
- 
-It will output a string like below: 
- 
-<code> 
-AGFkbWluQGV4YW1wbGUuY29tAHBhc3N3b3Jk 
-</code> 
- 
-Use above string with AUTH command: 
- 
-<code bash> 
-AUTH PLAIN AGFkbWluQGV4YW1wbGUuY29tAHBhc3N3b3Jk 
-</code> 
- 
- 
-===== SMTP Commands to send test email ===== 
- 
-Type/paste following commands 1-by-1.  They are interactive and needs input. 
- 
-<code bash> 
-ehlo example.com 
-mail from: admin@example.com 
-rcpt to: admin@other.com 
-data 
-quit 
-</code> 
- 
-For more SMTP Tests, check http://www.stat.ufl.edu/system/mailtesting.shtml. 
- 
-===== Open-Relay Test ===== 
- 
-Worst thing that could happen to your SMTP server is – it becomes open-relay (accidentally).  An open-relay allows anybody to connect and send email using your server.  It can lead to your server being blacklisted.  I am not sure if it can result in legal hassles! 
- 
-There are many tools available online which can check if your smtp server is acting as open relay. 
- 
-===== swaks utility ===== 
- 
-This is a small package which can make it easy to test your smtp server. 
- 
-<code bash> 
-apt-get install swaks 
-</code> 
- 
-Example usage: 
- 
-<code bash> 
-swaks --server example.com --to admin@example.com 
-</code> 
- 
-<WRAP info> 
-Please note that SpamAssassin marks, swaks generated email as spam. 
-</WRAP> 
- 
- 
- 
-===== Example ===== 
- 
-openssl s_client -starttls smtp -connect mail.sharewiz.net:25 
-CONNECTED(00000003) 
-depth=0 C = UK, ST = Jersey, L = St. Helier, O = ShareWiz, OU = Tech, CN = mail.sharewiz.net, emailAddress = admin@sharewiz.net 
-verify error:num=18:self signed certificate 
-verify return:1 
-depth=0 C = UK, ST = Jersey, L = St. Helier, O = ShareWiz, OU = Tech, CN = mail.sharewiz.net, emailAddress = admin@sharewiz.net 
-verify return:1 
---- 
-Certificate chain 
- 0 s:/C=UK/ST=Jersey/L=St. Helier/O=ShareWiz/OU=Tech/CN=mail.sharewiz.net/emailAddress=admin@sharewiz.net 
-   i:/C=UK/ST=Jersey/L=St. Helier/O=ShareWiz/OU=Tech/CN=mail.sharewiz.net/emailAddress=admin@sharewiz.net 
---- 
-Server certificate 
------BEGIN CERTIFICATE----- 
-MIIF/TCCA+WgAwIBAgIJAMDVKowLC7NQMA0GCSqGSIb3DQEBCwUAMIGUMQswCQYD 
-VQQGEwJVSzEPMA0GA1UECAwGSmVyc2V5MRMwEQYDVQQHDApTdC4gSGVsaWVyMREw 
-DwYDVQQKDAhTaGFyZVdpejENMAsGA1UECwwEVGVjaDEaMBgGA1UEAwwRbWFpbC5z 
-aGFyZXdpei5uZXQxITAfBgkqhkiG9w0BCQEWEmFkbWluQHNoYXJld2l6Lm5ldDAe 
-Fw0xNjExMDYxOTMwNTZaFw00MTA2MjgxOTMwNTZaMIGUMQswCQYDVQQGEwJVSzEP 
-MA0GA1UECAwGSmVyc2V5MRMwEQYDVQQHDApTdC4gSGVsaWVyMREwDwYDVQQKDAhT 
-aGFyZVdpejENMAsGA1UECwwEVGVjaDEaMBgGA1UEAwwRbWFpbC5zaGFyZXdpei5u 
-ZXQxITAfBgkqhkiG9w0BCQEWEmFkbWluQHNoYXJld2l6Lm5ldDCCAiIwDQYJKoZI 
-hvcNAQEBBQADggIPADCCAgoCggIBAKY1Smx6HoH7QvC4pLvmS8jcVqLfR81IJc0+ 
-D/N3VfTrz6DFJ4fkkzyDGipHDZCSbg++K8AxWvCSIkH69Cdpa6PcfD0f07dKLNCd 
-t4S+dUPbSwwOXcnttlE974eJBqgtRsQs96BXqdF4Lny+6LDLolV3uwyrnASgV3xX 
-CHAc5hbnJaj8ArxPhXa7ZKKDP04SJ+5U9J47eW/pedUc89O7NeKuaSNQ4ZlnAEbu 
-aBiHocgk9hPUhLV1i+85IKck7xf9v/bzEdX7pkFdLRu16jJUbZXxmI8zj1ZlZhix 
-5NfC8+l6NX5PIaJqYhXjGFLiD72178mlLMUSQFTgZF//tfqtccQNI6oPl2xhY2iq 
-TUFUmSf1efvJvBQhK3vWCCpVhnvBBgABxQOV/ydzsuY91Meu+r8OiQlHiTYofKTt 
-C1zfCZrIIU+O9NhpgSWoxpO9OLjFTo+xf5t8D3PP7soH1T+W0m0ygkvNBNTVAGYS 
-rzUAmnvQho7Rk/QrdWQ1x6wLVXqaAQe9E7ICPpr8IqIC9Wtd03kilPtOJcwX8Jbc 
-W+Im224O+qClT55IDOdeEG5PouNOLJEBNDUbco7eo8qJL1L6dlgOGI5a3vn9Ha+r 
-uSD3KjElvgnzZGcyGOwEybU+PEvZ4Fw6v3RhIBoogKkSaiU2TGAg8nC/PMUJuf7p 
-O4DnuJP9AgMBAAGjUDBOMB0GA1UdDgQWBBTXgStBGVqML4FnPwZSkP7brXT8wzAf 
-BgNVHSMEGDAWgBTXgStBGVqML4FnPwZSkP7brXT8wzAMBgNVHRMEBTADAQH/MA0G 
-CSqGSIb3DQEBCwUAA4ICAQBVaSDMRoB0tjHVJPSpBQmvVw4KyhN1eHf7Pe/gLNaZ 
-MzXxzt7USxSXXcUYb6mzn1KuQozXr0cTF2Mqg9oUxJWp/IE6uyCKkJ1DM8EnATOC 
-wkySwS3eZ73HnpeofNY9V7t8rdHE8uMD/AgCnaYztgnC/AxD4xcZaBBvbD1AnHuz 
-IlPc6KaRTtV3PQM+Za0zfJ4ukxR2YwPU68Df8T50whp1eJnj7Tg1Z7ZUkL5iRkLO 
-ALdtlGI1qhVBZzstjL11rOUQH5zFHtu+hcAHM5UWqy04M4fFW6A3Fk/+TT0Mrlpa 
-bxbMvMTn85juoOkPYexhkQmLULqRmYgTR9YjqsPdmYi9OWBjciuoB9xePsR4U82k 
-o0WlztvY2XLCZh0DERaT6cLp0N+KIKOrjhO5eqSPOyQnGaTDZOokBGKUVUbRiF+1 
-L4xdF4rNyOo9anLrLjA+VBsTH8Ff3M50+VkQi/IpqswwTn90XudJxjoG9ZJ3Hput 
-Jj112fy6V7xN5zszxTi2ZLQ8lIFYsb36GSOrJLiTm4QS4NffvN53XTfoJTKu4Qlj 
-oQY3tI4QETunbFZxQF39wrgzvfwoFjw66ZczWuu2sQ8V1uhe5pe++YY/Dmc793zF 
-xuBv8Fx1CPR9oFBJnpZ61YGP08aRRsucsjwpC5RneTkxXSUSFC0ZS+SBVU4ar1tP 
-lg== 
------END CERTIFICATE----- 
-subject=/C=UK/ST=Jersey/L=St. Helier/O=ShareWiz/OU=Tech/CN=mail.sharewiz.net/emailAddress=admin@sharewiz.net 
-issuer=/C=UK/ST=Jersey/L=St. Helier/O=ShareWiz/OU=Tech/CN=mail.sharewiz.net/emailAddress=admin@sharewiz.net 
---- 
-No client certificate CA names sent 
-Peer signing digest: SHA512 
-Server Temp Key: ECDH, P-256, 256 bits 
---- 
-SSL handshake has read 2483 bytes and written 466 bytes 
---- 
-New, TLSv1/SSLv3, Cipher is ECDHE-RSA-AES256-GCM-SHA384 
-Server public key is 4096 bit 
-Secure Renegotiation IS supported 
-Compression: NONE 
-Expansion: NONE 
-No ALPN negotiated 
-SSL-Session: 
-    Protocol  : TLSv1.2 
-    Cipher    : ECDHE-RSA-AES256-GCM-SHA384 
-    Session-ID: B687474275FE380364B1CB8510743A4EB39898D34E85AC4137B5C29FB190E2F7 
-    Session-ID-ctx:  
-    Master-Key: E999FFA4C1791FBAA6442D546EF59BE650FED80C96D3EDF4A078473CD5BB86D934079514BFC840DDACA900D46721241A 
-    Key-Arg   : None 
-    PSK identity: None 
-    PSK identity hint: None 
-    SRP username: None 
-    Start Time: 1478819857 
-    Timeout   : 300 (sec) 
-    Verify return code: 18 (self signed certificate) 
---- 
-250 HELP 
-ehlo sharewiz.net 
-250-server1.sharewiz.net Hello gateway.sharewiz.net [192.168.1.1] 
-250-SIZE 52428800 
-250-8BITMIME 
-250-PIPELINING 
-250-AUTH PLAIN LOGIN PLAIN2 LOGIN2 
-250 HELP 
-AUTH PLAIN Base64EncodedUsernameAndPassword== 
-235 Authentication succeeded 
-ehlo sharewiz.net 
-250-server1.sharewiz.net Hello gateway.sharewiz.net [192.168.1.1] 
-250-SIZE 52428800 
-250-8BITMIME 
-250-PIPELINING 
-250 HELP 
-mail from:peter@sharewiz.net 
-250 OK 
-rcpt to:mail@peterroux.com 
-250 Accepted 
-data 
-354 Enter message, ending with "." on a line by itself 
-This is a test 
-. 
-250 OK id=1c4yeV-000NPI-HC 
-quit 
-221 server1.sharewiz.net closing connection 
-closed 
-</code> 
  
email/test_smtp.1478824061.txt.gz · Last modified: 2020/07/15 09:30 (external edit)
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