general language fixup for the chapter 'rule-based mail filter' Signed-off-by: Dylan Whyte --- pmg-mail-filter.adoc | 95 ++++++++++++++++++++++++-------------------- 1 file changed, 51 insertions(+), 44 deletions(-) diff --git a/pmg-mail-filter.adoc b/pmg-mail-filter.adoc index fa9d3a0..3aafe4c 100644 --- a/pmg-mail-filter.adoc +++ b/pmg-mail-filter.adoc @@ -2,13 +2,13 @@ Rule-Based Mail Filter ====================== -{pmg} ships with a highly configurable mail filter. It’s an easy but -powerful way to define filter rules by user, domains, time frame, -content type and resulting action. +{pmg} ships with a highly configurable mail filter. This provides an +easy but powerful way to define filter rules by user, domain, time +frame, content type, and resulting action. [thumbnail="pmg-gui-mail-filter-rules.png", big=1] -Every rule has 5 categories ('FROM', 'TO', 'WHEN', 'WHAT' and +Every rule has 5 categories ('FROM', 'TO', 'WHEN', 'WHAT', and 'ACTION'), and each category may contain several objects to match certain criteria: @@ -48,14 +48,14 @@ Example: Mark email with “SPAM:” in the subject. Rules are ordered by priority, so rules with higher priority are executed first. It is also possible to set a processing direction: -'In':: Rule applies for all incoming emails +'In':: Rule applies to all incoming emails -'Out':: Rule applies for all outgoing emails +'Out':: Rule applies to all outgoing emails -'In & Out':: Rule applies for both directions +'In & Out':: Rule applies to both directions -And you can also disable a rule completely, which is mostly useful for -testing and debugging. The 'Factory Defaults' button alows you to +You can also disable a rule completely, which is mostly useful for +testing and debugging. The 'Factory Defaults' button allows you to reset the filter rules. @@ -83,7 +83,7 @@ Block mail. This is a 'final' action. Quarantine ~~~~~~~~~~ -Move to quarantine (virus mails are moved to the “virus quarantine”, +Move to quarantine (virus mails are moved to the “virus quarantine”; other mails are moved to “spam quarantine”). This is also a 'final' action. @@ -118,14 +118,18 @@ Blind Carbon Copy (BCC) The BCC object simply sends a copy to another target. It is possible to send the original unmodified mail, or the processed result. Please -note that this can be quite different, i.e. when a previous rule +note that this can be quite different, for instance, when a previous rule removed attachments. Header Attributes ~~~~~~~~~~~~~~~~~ -This object is able to add or modify mail header attributes. As with notifications above, you can use xref:rule_system_macros[macros], making this a very powerful object. For example, the 'Modify Spam Level' actions adds detailed information about detected Spam characteristics to the `X-SPAM-LEVEL` header. +This object is able to add or modify mail header attributes. As with +Notifications above, you can use xref:rule_system_macros[macros], +making this a very powerful object. For example, the 'Modify Spam +Level' actions add detailed information about detected Spam +characteristics to the `X-SPAM-LEVEL` header. .'Modify Spam Level' Header Attribute ---- @@ -147,14 +151,14 @@ Remove attachments ~~~~~~~~~~~~~~~~~~ Remove attachments can either remove all attachments, or only those -matched by the rules 'What' - object. You can also specify the -replacement text if you want. +matched by the rule's 'What' - object. You can also specify the +replacement text, if you want. -You can optionally move those mails into the attachment quarantine, where +You can optionally move these mails into the attachment quarantine, where the original mail with all attachments will be stored. The mail with the -attachments removed will continue in the rule system. +attachments removed will continue through the rule system. -NOTE: The Attachment Quarantine Lifetime is the same as for the Spam Quarantine. +NOTE: The Attachment Quarantine lifetime is the same as for the Spam Quarantine. Disclaimer @@ -168,12 +172,12 @@ its text can be encoded in the mail's character encoding. [[pmg_mailfilter_who]] -'Who' - objects ---------------- +'Who' objects +------------- [thumbnail="pmg-gui-mail-filter-who-objects.png", big=1] -This type of objects can be used for the 'TO' and/or 'FROM' category, +These types of objects can be used for the 'TO' and/or 'FROM' category, and match the sender or recipient of the email. A single object can combine multiple items, and the following item types are available: @@ -197,24 +201,25 @@ LDAP User or Group:: Test if the mail address belongs to a specific LDAP user or group. -We have two important 'Who' - objects called 'Blacklist' and +We have two important 'Who' objects called 'Blacklist' and 'Whitelist'. These are used in the default ruleset to globally block or allow specific senders. [[pmg_mailfilter_what]] -'What' - objects ----------------- +'What' objects +-------------- [thumbnail="pmg-gui-mail-filter-what-objects.png", big=1] -'What' - objects are used to classify the mail content. A single +'What' objects are used to classify the mail's content. A single object can combine multiple items, and the following item types are available: Spam Filter:: -Matches if detected spam level is equal or greater than the configured value. +Matches if the detected spam level is greater than or equal to the +configured value. Virus Filter:: @@ -222,7 +227,7 @@ Matches on infected mails. Match Field:: -Match specified mail header fields (eg. `Subject:`, `From:`, ...) +Match specified mail header fields (for example, `Subject:`, `From:`, ...) Content Type Filter:: @@ -244,13 +249,13 @@ This also matches the filenames for all regular (non-archived) attachments. [[pmg_mailfilter_when]] -'When' - objects ----------------- +'When' objects +-------------- [thumbnail="pmg-gui-mail-filter-when-objects.png", big=1] -'When' - objects are use to activate rules at specific daytimes. You -can compose them of one or more time frame items. +'When' objects are used to activate rules at specific times of the +day. You can compose them from one or more time frame items. The default ruleset defines 'Office Hours', but this is not used by the default rules. @@ -260,10 +265,11 @@ the default rules. Using regular expressions ------------------------- -A regular expression is a string of characters which tells us which -string you are looking for. The following is a short introduction in -the syntax of regular expressions used by some objects. If you are -familiar with Perl, you already know the syntax. +A regular expression is a string of characters which represents a list +of text patterns which you would like to match. The following is a +short introduction to the syntax of regular expressions used by some +objects. If you are familiar with Perl, you will already know the +syntax. Simple regular expressions ~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -285,19 +291,20 @@ The question mark (`?`) indicates that the character immediately preceding it shows up either zero or one time. `e?mail` would match either "email" or "mail" but not "e-mail". -Another metacharacter is the star (`*`). This indicates that the +Another metacharacter is the asterisk (`*`). This indicates that the character immediately preceding it may be repeated any number of times, -including zero. `e*mail` would match either "email" or "mail" or +including zero. `e*mail` would match "email", "mail", and "eeemail". -The plus (`+`) metacharacter does the same as the star (*) excluding -zero. So `e+mail` does not match "mail". +The plus (`+`) metacharacter indicates that the character immediately +preceding it appears one or more times. So `e+mail` does not match +"mail". -Metacharacters may be combined. A common combination includes the -period and star metacharacters (`.*`), with the star immediately following -the period. This is used to match an arbitrary string of any length, -including the null string. For example: `.*company.*` matches -"company@domain.com" or "company@domain.co.uk" or -"department.company@domain.com". +Metacharacters can also be combined. A common combination includes the +period and asterisk metacharacters (`.*`), with the asterisk +immediately following the period. This is used to match an arbitrary +string of any length, including the null string. For example: +`.*company.*` matches "company@domain.com" or "company@domain.co.uk" +or "department.company@domain.com". The book xref:Friedl97[] provides a more comprehensive introduction. -- 2.20.1