Form Mail Information
Copyright 2001 London Perl Mongers, All rights reserved
The most up to date version of this script is available from the nms script archive at <http://nms-cgi.sourceforge.net/>
formmail is a script which allows you to receive the results of an HTML form submission via an email message.
There are a number of variables that you can change in FormMail.pl which alter the way that the program works.
- This should be set to 1 while you are installing and testing the script. Once the script is live you should change it to 0. When set to 1, errors will be output to the browser. This is a security risk and should not be used when the script is live.
- When this variable is set to a true value (e.g. 1) formmail will work in exactly the same way as its counterpart at Matt's Script Archive. If it is set to a false value (e.g. 0) then more advanced features are switched on. We do not recommend changing this variable to 1, as the resulting drop in security may leave your formmail open to use as a SPAM relay.
- When this variable is set to a true value (e.g. 1) many additional security features are turned on. We do not recommend changing this variable to 0, as the resulting drop in security may leave your formmail open to use as a SPAM relay.
- Some web proxies and office firewalls may strip certain headers from the HTTP request that is sent by a browser. Among these is the HTTP_REFERER that the program uses as an additional check of the requests validity. This will cause the program to fail with a 'bad referer' message even though the configuration seems fine. In these cases setting this variable to 1 will stop the program from complaining about requests where no referer header was sent while leaving the rest of the security features intact.
- The maximum number of e-mail addresses that any single form should be allowed to send copies of the e-mail to. If none of your forms send e-mail to more than one recipient, then we recommend that you improve the security of FormMail by reducing this value to 1. Setting this variable to 0 removes all limits on the number of recipients of each e-mail.
- The system command that the script should invoke to send an outgoing email. This should be the full path to a program that will read a message from STDIN and determine the list of message recipients from the message headers. Any switches that the program requires should be provided here. Your hosting provider or system administrator should be able to tell you what to set this variable to.
- A list of referring hosts. This should be a list of the names or IP addresses of all the systems that will host HTML forms that refer to this formmail script. Only these hosts will be allowed to use the formmail script. This is needed to prevent others from hijacking your formmail script for their own use by linking to it from their own HTML forms.
- A list of the email addresses that formmail can send email to. The elements of this list can be either simple email addresses (like 'firstname.lastname@example.org') or domain names (like 'your.domain'). If it's a domain name then *any* address at the domain will be allowed.
Example: to allow mail to be sent to 'email@example.com' or any address at the host 'mail.your.domain', you would set:
@allow_mail_to = qw(firstname.lastname@example.org mail.your.domain);
- A list of Perl regular expression patterns that determine who the script will allow mail to be sent to in addition to those set in @allow_mail_to. This is present only for compatibility with the original formmail script. We strongly advise against having anything in @recipients as it's easy to make a mistake with the regular expression syntax and turn your formmail into an open SPAM relay.
There is an implicit $ at the end of the regular expression, but you need to include the ^ if you want it anchored at the start. Note also that since '.' is a regular expression metacharacter, you'll need to escape it before using it in domain names.
If that last paragraph makes no sense to you then please don't put anything in @recipients, stick to using the less error prone @allow_mail_to.
- A hash for predefining a list of recipients in the script, and then choosing between them using the recipient form field, while keeping all the email addresses out of the HTML so that they don't get collected by address harvesters and sent junk email.
For example, suppose you have three forms on your site, and you want each to submit to a different email address and you want to keep the addresses hidden. You might set up %recipient_alias like this:
%recipient_alias = (
'1' => 'email@example.com',
'2' => 'firstname.lastname@example.org',
'3' => 'email@example.com',
In the HTML form that should submit to the recipient 'firstname.lastname@example.org', you would then set the recipient with:
<input type="hidden" name="recipient" value="2" />
- This determines the language that is used in the date – by default this is blank and the language will probably be english. The following a list of some possible values, however it should be stressed that not all of these will be supported on all systems and also this is not a complete list:
- The character set to use for output documents.
- If this is set to 1 then rather than returning the HTML confirmation page or doing a redirect the script will output a header that indicates that no content will be returned and that the submitted form should not be replaced. This should be used carefully as an
unwitting visitor may click the submit button several times thinking that nothing has happened.
- If this is set to 1 then the content of any long text fields will be wrapped at around 72 columns in the e-mail which is sent. The way that this is done is controlled by the variable $wrap_style
- If $wrap_text is set to 1 then if this is set to 1 then the text will be wrapped in such a way that the left margin of the text is lined up with the beginning of the text after the description of the field - that is to say it is indented by the length of the field name plus 2. If it is set to 2 then the subsequent linesof the text will not be indented at all and will be
flush with the start of the lines. The choice of style is really a matter of taste although you might find that style 1 does not work particularly well if your e-mail client uses a proportional font where the spaces of the indent might be smaller than the characters in
the field name.
- This optional configuration may contain a list of the names of certain configuration form fields (as described below) that may be included in the body of the e-mail that is sent and also in the confirmation page that is returned to the visitors browser. In
order for these fields to be actually displayed they should be included in the value of a 'sort' field explicitly ( along with the other fields that want to be displayed ). You probably want to use this sparingly as most of the configuration fields will be meaningless to a visitor.
- A list of all the environment variables that you want to be able to include in the email. See 'env_report' below.
- The format that the date will be displayed in. This is a string that contains a number of different 'tags'. Each tag consists of a % character followed by a letter. Each tag represents one way of displaying a particular part of the date or time. Here are some common tags:
%Y - four digit year (2002)
%y - two digit year (02)
%m - month of the year (01 to 12)
%b - short month name (Jan to Dec)
%B - long month name (January to December)
%d - day of the month (01 to 31)
%a - short day name (Sun to Sat)
%A - long day name (Sunday to Saturday)
%H - hour in 24 hour clock (00 to 23)
%I - hour in 12 hour clock (01 to 12)
%p - AM or PM
%M - minutes (00 to 59)
%S - seconds (00 to 59)
%Z - the name of the local timezone
- This is the URL of a CSS stylesheet which will be used for script generated messages. This should probably be the same as the one that you use for all the other pages. This should be a local absolute URI fragment. Set $style to '0' or the emtpy string if you don't want to use style sheets.
- If this flag is set to 1 then an additional email will be sent to the person who submitted the form.
CAUTION: with this feature turned on it's possible for someone to put someone else's email address in the form and submit it 5000 times, causing this script to send a flood of email to a third party. This third party is likely to blame you for the email flood attack.
$confirmation_text - The header and body of the confirmation email sent to the person who submits the form, if the $send_confirmation_mail flag is set. We use a Perl 'here document' to allow us to configure it as a single block of text in the script. In the example below, everything between the lines
$confirmation_text = <<'END_OF_CONFIRMATION';
is treated as part of the email. Everything before the first blank line is taken as part of
the email header, and everything after the first
blank line is the body of the email.
$confirmation_text = <<'END_OF_CONFIRMATION';
Subject: form submission
Thankyou for your form submission.
Please contact email@example.com to request formmail.pl provisioned for your domain.
To make use of it, you need to write an HTML form that refers to the FormMail script. Here's an example which will send mail to the address firstname.lastname@example.org when someone submits the form:
See how the hidden 'recipient' input in the example above told formmail who to send the mail to ? This is how almost all of formmail's configuration works. Here's the full list of things you can set with hidden form inputs:
- The email address to which the form submission should be sent. If you would like it copied to more than one recipient then you can separate multiple email addresses with commas, for example:
<input type="hidden" name="recipient" value="email@example.com,firstname.lastname@example.org" />
If you leave the 'recipient' field out of the form, formmail will send to the first address
listed in the @allow_mail_to configuration variable (see above). This allows you to avoid putting your email address in the form, which might be desirable if you're concerned about address harvesters collecting it and sending you SPAM. This feature is disabled if the $emulate_matts_code configuration variable is set to 0.
- The subject line for the email. For example:
<input type="hidden" name="subject" value="From the feedback form" />
- If this value is present it should be a URL, and the user will be redirected there after a
successful form submission. For example:
<input type="hidden" name="redirect" value="http://www.your.domain/foo.html" />
If you don't specify a redirect URL then instead of redirecting formmail will generate a success page telling the user that their submission was successful.
- The background color for the success page.
- The URL of the background image for the success page.
- The text color for the success page.
- The link color for the success page.
- The vlink color for the success page.
- The alink color for the success page.
- The title for the success page.
- The target URL for a link at the end of the success page. This is normally used to provide a link from the success page back to your main page or back to the page with the form on. For example:
<input type="hidden" name="return_link_url" value="/home.html" />
- The label for the return link. For example:
<input type="hidden" name="return_link_title" value="Back to my home page" />
- This sets the order in which the submitted form inputs will appear in the email and on the success page. It can be the string 'alphabetic' for alphabetic order, or the string "order:" names, for example:
<input type="hidden" name="sort" value="order:name,email,age,comments">
If "order:" is used you must supply the names of all of the fields that you want to be in the body of the mail message.
- This is mainly used for debugging, and if set it causes formmail to include a dump of the specified configuration settings in the email.
<input type="hidden" name="print_config" value="title,sort">
... will include whatever values you set for 'title' and 'sort' (if any) in the email.
- This is a list of fields that the user must fill in before they submit the form. If they leave
any of these fields blank then they will be sent back to the form to try again. For example:
<input type="hidden" name="required" value="name,comments">
- If this is set, it must be a URL, and the user ill be redirected there if any of the fields listed in 'required' are left blank. Use this if you want finer control over the the error that the user see's if they miss out a field.
- This is a list of the CGI environment variables that should be included in the email. This is useful for recording things like the IP address of the user in the email. Any environment variables that you want to use in 'env_report' in any of your forms will need to be in the @valid_ENV configuration variable described above.
- If this is set then fields that the user left blank will be included in the email. Normally, blank fields are suppressed to save space.
As well as all these hidden inputs, there are a couple of non-hidden inputs which get special treatment:
- If one of the things you're asking the user to fill in is their email address and you call that input 'email', formmail will use it as the address part of the sender's email address in the email.
- If one of the things you're asking the user to fill in is their full name and you call that input 'realname', formmail will use it as the name part of the sender's email address in the email.
For support of this script please email: email@example.com