Add doc and fix mms message class

documentation/modules/auxiliary/client/mms/send_mms.md

@@ -0,0 +1,144 @@
+The ```auxiliary/client/mms/send_mms``` module allows you to send a malicious attachment to a
+collection of phone numbers of the same carrier.
+
+In order to use this module, you must set up your own SMTP server to deliver messages. Popular
+mail services such as Gmail, Yahoo, Live should work fine.
+
+## Module Options
+
+**CELLNUMBERS**
+
+The 10-digit phone number (or numbers) you want to send the MMS text to. If you wish to target
+against multiple phone numbers, ideally you want to create the list in a text file (one number per
+line), and then load the CELLNUMBERS option like this:
+
+```
+set CELLNUMBERS file:///tmp/att_phone_numbers.txt
+```
+
+Remember that these phone numbers must be the same carrier.
+
+**MMSCARRIER**
+
+The carrier that the targeted numbers use. See **Supported Carrier Gateways** to learn more about
+supported carriers.
+
+**TEXTMESSAGE**
+
+The text message you want to send. For example, this will send a text with a link to google:
+
+```
+set TEXTMESSAGE "Hi, please go: google.com"
+```
+
+The link should automatically be parsed on the phone and clickable.
+
+**MMSFILE**
+
+The attachment to send in the message.
+
+**MMSFILECTYPE**
+
+The content type to use for the attachment. Commonly supported ones include:
+
+* audio/midi
+* image/jpeg
+* image/gif
+* image/png
+* video/mp4
+
+To find more, please try this [list](http://www.freeformatter.com/mime-types-list.html)
+
+**SMTPADDRESS**
+
+The mail server address you wish to use to send the MMS messages.
+
+**SMTPPORT**
+
+The mail server port. By default, this is ```25```.
+
+**SMTPUSERNAME**
+
+The username you use to log into the SMTP server.
+
+**SMTPPASSWORD**
+
+The password you use to log into the SMTP server.
+
+**SMTPFROM**
+
+The FROM field of SMTP. In some cases, it may be used as ```SMTPUSER```.
+
+## Supported Carrier Gateways
+
+The module supports the following carriers:
+
+* AT&T
+* Sprint
+* T-Mobile
+* Verizon
+
+## Finding the Carrier for a Phone Number
+
+Since you need to manually choose the carrier gateway for the phone numbers, you need to figure out
+how to identify the carrier of a phone number. There are many services that can do this, such as:
+
+http://freecarrierlookup.com/
+
+## Gmail SMTP Example
+
+Gmail is a popular mail server, so we will use this as a demonstration.
+
+Assuming you are already using two-factor authentication, you need to create an [application password](https://support.google.com/accounts/answer/185833?hl=en).
+
+After creating the application password, configure auxiliary/client/mms/send_mms this way:
+
+* ```set cellnumbers [PHONE NUMBER]```
+* ```set mmscarrier [CHOOSE A SUPPORTED CARRIER]```
+* ```set textmessage "[TEXT MESSAGE]"```
+* ```set smtpaddress smtp.gmail.com```
+* ```set smtpport 587```
+* ```set mmsfile /tmp/example.mp4```
+* ```set mmsfilectype video/mp4```
+* ```set smtpusername [USERNAME FOR GMAIL]``` (you don't need ```@gmail.com``` at the end)
+* ```set smtppassword [APPLICATION PASSWORD]```
+
+And you should be ready to go.
+
+## Yahoo SMTP Example
+
+Yahoo is also a fairly popular mail server (although much slower to deliver comparing to Gmail),
+so we will demonstrate as well.
+
+Before using the module, you must do this to your Yahoo account:
+
+1. Sign in to Yahoo Mail.
+2. [Go to your "Account security" settings.](https://login.yahoo.com/account/security#less-secure-apps)
+3. Turn on Allow apps that use less secure sign in.
+
+After configuring your Yahoo account, configure auxiliary/client/mms/send_mms this way:
+
+* ```set cellnumbers [PHONE NUMBER]```
+* ```set mmscarrier [CHOOSE A SUPPORTED CARRIER]```
+* ```set textmessage "[TEXT MESSAGE]"```
+* ```set smtpaddress smtp.mail.yahoo.com```
+* ```set smtpport 25```
+* ```set mmsfile /tmp/example.mp4```
+* ```set mmsfilectype video/mp4```
+* ```set smtpusername [USERNAME FOR YAHOO]@yahoo.com```
+* ```set smtppassword [YAHOO LOGIN PASSWORD]```
+
+And you're good to go.
+
+## Demonstration
+
+After setting up your mail server and the module, your output should look similar to this:
+
+```
+msf auxiliary(send_mms) > run
+
+[*] Sending mms message to 1 number(s)...
+[*] Done.
+[*] Auxiliary module execution completed
+msf auxiliary(send_mms) > 
+```

lib/rex/proto/mms/model/message.rb

@@ -82,7 +82,7 @@ module Rex
             body = Rex::MIME::Message.new
             body.add_part(text.to_s, "multipart/alternative; boundary=#{text.bound}", nil)
             if self.attachment
-              body.add_part(self.attachment, "image/jpeg; name=\"#{attachment_name}\"", 'base64', "attachment; filename=\"#{attachment_name}\"")
+              body.add_part(self.attachment, "#{content_type}; name=\"#{attachment_name}\"", 'base64', "attachment; filename=\"#{attachment_name}\"")
             end
 
             mms = "MIME-Version: 1.0\n"