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diff --git a/man/man5/unlang.5 b/man/man5/unlang.5 new file mode 100644 index 0000000..63f5570 --- /dev/null +++ b/man/man5/unlang.5 @@ -0,0 +1,900 @@ +.\" # DS - begin display +.de DS +.RS +.nf +.sp +.. +.\" # DE - end display +.de DE +.fi +.RE +.sp +.. +.TH unlang 5 "16 February 2021" "" "FreeRADIUS Processing un-language" +.SH NAME +unlang \- FreeRADIUS Processing un\-language +.SH DESCRIPTION +FreeRADIUS supports a simple processing language in its configuration +files. We call it an "un-language" because the intention is NOT to +create yet another programming language. If you need something more +complicated than what is described here, we suggest using the Perl or +Python modules rlm_perl, or rlm_python. + +The goal of the language is to allow simple policies to be written +with minimal effort. Those policies are then applied when a request +is being processed. Requests are processed through virtual servers +(including the default one), in the sections titled "authorize", +"authenticate", "post-auth", "preacct", "accounting", "pre-proxy", +"post-proxy", and "session". + +These policies cannot be used in any other part of the configuration +files, such as module or client configuration. +.SH KEYWORDS +The keywords for the language are a combination of pre-defined +keywords, and references to loadable module names. We document only +the pre-defined keywords here. + +Subject to a few limitations described below, any keyword can appear +in any context. The language consists of a series of entries, each +one line. Each entry begins with a keyword. Entries are +organized into lists. Processing of the language is line by line, +from the start of the list to the end. Actions are executed +per-keyword. +.IP module-name[.section-name] +A reference to the named module. When processing reaches this point, +the pre-compiled module is called. The module may succeed or fail, +and will return a status to "unlang" if so. This status can be tested +in a condition. See the "Simple Conditions" text in the CONDITIONS +section, and MODULE RETURN CODES, below. +If a section-name is provided, it will cause the module to execute +as if it were listed in the named section. + +.DS + chap # call the CHAP module +.br + sql # call the SQL module +.br + ... +.DE +.IP if +.br +Checks for a particular condition. If true, the block after the +condition is processed. Otherwise, the block is ignored. See +CONDITIONS, below, for documentation on the format of the conditions. + +.DS + if (condition) { +.br + ... +.br + } +.DE +.IP else +.br +Define a block to be executed only if the previous "if" condition +returned false. + +.DS + else { +.br + ... +.br + } +.DE +.IP elsif +.br +Define a block to be executed only if the previous "if" condition +returned false, and if the specified condition evaluates to true. + +.DS + elsif (condition) { +.br + ... +.br + } +.DE +.IP foreach +.br +Loops over values of an attribute, running the block for each value. +The return value of the block is the return value of the last +statement executed. The loop can be exited early by using the "break" +keyword. Unlike other languages, "break" here means "exit the loop at +the next iteration", not "exit the loop now". The result is that any +statements after the "break" keyword will still be executed. We +recommend using "break" only when it is the last statement in a +"foreach" block. + +Inside of the "foreach" block, the attribute which is being looped +over can be referenced as "Foreach-Variable-#". Where "#" is the +depth of the loop, starting at "0". e.g. "Foreach-Variable-0". The +loops can be nested up to eight (8) deep, though this is not +recommended. + +.DS + foreach &Attribute-Reference { +.br + ... +.br + } +.DE +.IP switch +.br +A "switch" statement takes one argument, and contains a series of +"case" statements. When a "switch" statement is encountered, the +argument from the "switch" is evaluated in turn against the argument +from each "case" statement. The first "case" statement which matches +is executed. All other "case" statements are ignored. A default +"case" statement can be defined, by omitting its argument. + +If the argument is a double quoted string (e.g. "%{exec:1 + 2}", it is +expanded as described in the DATA TYPES section, below. The match is +then performed on the string returned from the expansion. If the +argument is an attribute reference (e.g. &User-Name), then the match +is performed on the value of that attribute. Otherwise, the argument +is taken to be a literal string, and matching is done via simple +comparison. + +No statement other than "case" can appear in a "switch" block. + +.DS + switch <argument> { +.br + ... +.br + } +.DE +.IP case +.br +Provides a place-holder which matches the argument of a parent +"switch" statement. + +A "case" statement cannot appear outside of a "switch" block. + +If the argument is a double quoted string (e.g. "%{exec:1 + 2}", it is +expanded as described in the DATA TYPES section, below. The match is +then performed on the string returned from the expansion. If the +argument is an attribute reference (e.g. &User-Name), then the match +is performed on the value of that attribute. Otherwise, the argument +is taken to be a literal string, and matching is done via simple +comparison. + +.DS + case <argument> { +.br + ... +.br + } +.DE +A default entry can be defined by omitting the argument, as given +below. This entry will be used if no other "case" entry matches. +Only one default entry can exist in a "switch" section. + +.DS + case { +.br + ... +.br + } +.DE +.IP update +.br +Update a particular attribute list, based on the attributes given in +the current block. + +.DS + update <list> { +.br + &Attribute-Reference = value +.br + ... +.br + } +.DE +The <list> can be one of "request", "reply", "proxy-request", +"proxy-reply", "coa", "disconnect", "session-state", or "control". As +of Version 3, the <list> can be omitted, in which case "request" is +assumed. + +The "control" list is the list of attributes maintained internally by +the server that controls how the server processes the request. Any +attribute that does not go in a packet on the network will generally +be placed in the "control" list. + +For EAP methods with tunneled authentication sessions (i.e. PEAP and +EAP-TTLS), the inner tunnel session can also reference +"outer.request", "outer.reply", and "outer.control". Those references +allow you to address the relevant list in the outer tunnel session. + +The "coa" and "disconnect" sections can only be used when the server +receives an Access-Request or Accounting-Request. Use "request" and +"reply" instead of "coa" when the server receives a CoA-Request or +Disconnect-Request packet. + +Adding one or more attributes to either of the "coa" or "disconnect" +list causes server to originate a CoA-Request or Disconnect-Request +packet. That packet is sent when the current Access-Request or +Accounting-Request has been finished, and a reply sent to the NAS. +See raddb/sites-available/originate-coa for additional information. + +The "session-state" list is primarily used for EAP. Attributes put +into the "session-state" list are saved for the next packet in the +session. They are automatically retrieved when the next packet is +received. + +The only contents permitted in an "update" section are attributes and +values. The contents of the "update" section are described in the +ATTRIBUTE REFERENCE and ATTRIBUTE ASSIGNMENT sections below. +.IP redundant +This section contains a simple list of modules. The first module is +called when the section is being processed. If the first module +succeeds in its operation, then the server stops processing the +section, and returns to the parent section. + +If, however, the module fails, then the next module in the list is +tried, as described above. The processing continues until one module +succeeds, or until the list has been exhausted. + +Redundant sections can contain only a list of modules, and cannot +contain keywords that perform conditional operations (if, else, etc) +or update an attribute list. + +.DS + redundant { +.br + sql1 # try this +.br + sql2 # try this only if sql1 fails. +.br + ... +.br + } +.DE +.IP load-balance +This section contains a simple list of modules. When the section is +entered, one module is chosen at random to process the request. All +of the modules in the list should be the same type (e.g. ldap or sql). +All of the modules in the list should behave identically, otherwise +the load-balance section will return different results for the same +request. + +Load-balance sections can contain only a list of modules, and cannot +contain keywords that perform conditional operations (if, else, etc) +or update an attribute list. + +.DS + load-balance { +.br + ldap1 # 50% of requests go here +.br + ldap2 # 50% of requests go here +.br + } +.DE +In general, we recommend using "redundant-load-balance" instead of +"load-balance". +.IP redundant-load-balance +This section contains a simple list of modules. When the section is +entered, one module is chosen at random to process the request. If +that module succeeds, then the server stops processing the section. +If, however, the module fails, then one of the remaining modules is +chosen at random to process the request. This process repeats until +one module succeeds, or until the list has been exhausted. + +All of the modules in the list should be the same type (e.g. ldap or +sql). All of the modules in the list should behave identically, +otherwise the load-balance section will return different results for +the same request. + +Load-balance sections can contain only a list of modules, and cannot +contain keywords that perform conditional operations (if, else, etc) +or update an attribute list. Please see raddb/radiusd.conf +"instantiate" section for more configuration examples. + +.DS + redundant-load-balance { +.br + ldap1 # 50%, unless ldap2 is down, then 100% +.br + ldap2 # 50%, unless ldap1 is down, then 100% +.br + } +.DE +.IP return +.br +Returns from the current top-level section, e.g. "authorize" or +"authenticate". This keyword is mainly used to avoid layers of nested +"if" and "else" statements. + +.DS + authorize { +.br + if (...) { +.br + ... +.br + return +.br + } +.br + ... # this is never reached when the "if" +.br + ... # statement is executed +.br + } +.DE +.SH ATTRIBUTE REFERENCES + +Attributes may be referenced via the following syntax: +.DS + &Attribute-Name + &Attribute-Name:TAG + &Attribute-Name[NUM] + &<list>:Attribute-Name + &<list>:Attribute-Name:TAG[NUM] +.DE +Where <list> is one of "request", "reply", "control", "proxy-request", +"proxy-reply", or "outer.request", "outer.reply", "outer.control", +"outer.proxy-request", or "outer.proxy-reply". just as with the +"update" section, above. The "<list>:" prefix is optional, and if +omitted, is assumed to refer to the "request" list. + +The TAG portion is a decimal integer between 1 and 31. Please see RFC +2868 for more information about tags. Tags can only be used for +attributes which are marked in the dictionary as "has_tag". + +The NUM portion is used when there are multiple attributes of the same +name in a list. The "Attribute-Name" reference will return the first +attribute. Using an array offset allows the policy to refer to the +second and subsequent attributes. + +If '*' is used in the NUM portion, it evaluates to all instances of +the attribute in the request. + +If 'n' is used in the NUM portion, it evaluates to the last instance +of the attribute in the request. + +When an attribute name is encountered, the given list is examined for +an attribute of the given name. Some examples are: +.DS + User-Name +.br + request:User-Name # same as above +.br + reply:User-Name +.br + Tunnel-Password:1 +.br + Cisco-AVPAir[2] +.br + outer.request:User-Name # from inside of a TTLS/PEAP tunnel +.DE +Note that unlike C, there is no way to define new attributes at +run-time. They MUST be declared in a dictionary file, and loaded when +the server starts. + +All attributes are defined in the dictionaries that accompany the +server. These definitions define only the name and type, and do not +define the value of the attribute. When the server receives a packet, +it uses the packet contents to look up entries in the dictionary, and +instantiates attributes with a name taken from the dictionaries, and a +value taken from the packet contents. This process means that if an +attribute does not exist, it is usually because it was not contained +in a packet that the server received. + +Once the attribute is instantiated, it is added to a list. It can +then be referenced, updated, replaced, etc. + +.SH CONDITIONS +The conditions are similar to C conditions in syntax, though +quoted strings are supported, as with the Unix shell. +.IP Simple +conditions +.br +.DS + (foo) +.DE +Evaluates to true if 'foo' is a non-empty string (single quotes, double +quotes, or back-quoted). Also evaluates to true if 'foo' is a +non-zero number. Note that the language is poorly typed, so the +string "0000" can be interpreted as a numerical zero. This issue can +be avoided by comparing strings to an empty string, rather than by +evaluating the string by itself. + +If the word 'foo' is not a quoted string, then it can be taken as a +reference to a named attribute. See "Referencing attribute lists", +below, for examples of attribute references. The condition evaluates +to true if the named attribute exists. + +Otherwise, if the word 'foo' is not a quoted string, and is not an +attribute reference, then it is interpreted as a reference to a module +return code. The condition evaluates to true if the most recent +module return code matches the name given here. Valid module return +codes are given in MODULE RETURN CODES, below. +.IP Negation +.DS + (!foo) +.DE +Evaluates to true if 'foo' evaluates to false, and vice-versa. +.PP +Short-circuit operators +.RS +.br +.DS + (foo || bar) +.br + (foo && bar) +.DE +"&&" and "||" are short-circuit operators. "&&" evaluates the first +condition, and evaluates the second condition if and only if the +result of the first condition is true. "||" is similar, but executes +the second command if and only if the result of the first condition is +false. +.RE +.IP Comparisons +.DS + (foo == bar) +.DE +Compares 'foo' to 'bar', and evaluates to true if the comparison holds +true. Valid comparison operators are "==", "!=", "<", "<=", ">", +">=", "=~", and "!~", all with their usual meanings. The operators +":=", "^=" and "=" are assignment operators, and are not allowed for +comparisons. + +The operators "<", "<=", ">", and ">=" are also allowed for checking +that an IP address is contained within a network. For example: +.DS + if (<ipaddr>192.0.2.1 < 192.0.2.0/24) { +.DE +This comparison succeeds, because the address 192.0.2.1 is contained +within the network 192.0.2.0/24. +.RE +.IP "Attribute Comparisons" +When doing attribute comparisons, the data type of the attribute is +used to determine the data type of the right-hand side argument. +.DS + (&User-Name == "foo") +.DE +Compares the value of the User-Name attribute to the string 'foo', and +evaluates to true if the comparison holds true. + +Similarly, +.DS + (&Framed-IP-Address == 192.0.2.1) +.DE +Compares the value of the Framed-IP-Address attribute to the IP +address 192.0.2.1. This IP address does not need to be quoted. +.RE +.IP "Inter-Attribute Comparisons" +.DS + (&User-Name == &Filter-Id) +.DE +Compares the value of the User-Name attribute to the contents of the +Filter-Id attribute, and evaluates to true if the comparison holds +true. Unlike the previous example, this comparison is done in a +type-safe way. For example, comparing the IP addresses 1.2.3.4 and +127.0.0.1 as strings will return different results than comparing them +as IP addresses. + +The "&" character in the condition means that the comparison "refers" +to the Filter-Id attribute. If left off, it means that the User-Name +attribute is compared to the literal string "Filter-Id". + +Where the left-hand side is an attribute, the "&" can be omitted. +However, it is allowed for backwards compatibility. e.g. The comparison +"(&User-Name == &Filter-Id)" is equivalent to the example above. + +We recommend using attribute references instead of printing +attributes to a string, e.g. (User-Name == "%{Filter-Id}"). +Attribute references will be faster and more efficient. + +The conditions will check only the first occurrence of an attribute. +If there is more than one instance of an attribute, the following +syntax should be used: + +.DS + (&Attribute-Name[*] == "foo") +.DE +Using the "[*]" syntax means that it checks all of the instances of +the named attribute. If one attribute matches, the condition +succeeds. If none match, the condition fails. + +.RE +.IP Casts +.DS + (<type>foo == bar) +.DE +The left-hand-side of a condition can be "cast" to a specific data +type. The data type must be one which is valid for the dictionaries. +e.g. "integer", "ipaddr", etc. + +The comparison is performed in a type-safe way, as with +"Inter-Attribute Comparisons", above. Both sides of the condition are +parsed into temporary attributes, and the attributes compared via +type-specific methods. The temporary attributes have no other effect, +and are not saved anywhere. + +Casting allows conditions to perform type-specific comparisons. In +previous versions of the server, the data would have to be manually +placed into an intermediate attribute (or attributes), and then the +attribute (or attributes) compared. The use of a cast allows for +simpler policies. + +Casts are allowed only on the left-hand side argument of a condition. +.PP +Conditions may be nested to any depth, subject only to line length +limitations (8192 bytes). +.SH DATA TYPES +There are only a few data types supported in the language. Reference +to attributes, numbers, and strings. Any data type can appear in +stand-alone condition, in which case they are evaluated as described +in "Simple conditions", above. They can also appear (with some +exceptions noted below) on the left-hand or on the right-hand side of +a comparison. +.IP numbers +Numbers are composed of decimal digits. Floating point, hex, and +octal numbers are not supported. The maximum value for a number is +machine-dependent, but is usually 32-bits, including one bit for a +sign value. +.PP +word +.RS +Text that is not enclosed in quotes is interpreted differently +depending on where it occurs in a condition. On the left hand side of +a condition, it is interpreted as a reference to an attribute. On the +right hand side, it is interpreted as a simple string, in the same +manner as a single-quoted string. + +Using attribute references permits limited type-specific comparisons, +as seen in the examples below. + +.DS + if (&User-Name == "bob") { +.br + ... +.br + if (&Framed-IP-Address > 127.0.0.1) { +.br + ... +.br + if (&Service-Type == Login-User) { +.DE +.RE +.IP """strings""" +.RS +Double-quoted strings are expanded by inserting the value of any +attributes (see ATTRIBUTE REFERENCES, below) before being evaluated. If +the result is a number it is evaluated in a numerical context. + +String length is limited by line-length, usually about 8000 +characters. A double quote character can be used in a string via +the normal back-slash escaping method. ("like \\"this\\" !") +.RE +.IP 'strings' +Single-quoted strings are evaluated as-is. Their values are not +expanded as with double-quoted strings above, and they are not +interpreted as attribute references. +.IP `strings` +Back-quoted strings are evaluated by expanding the contents of the +string, as described above for double-quoted strings. The resulting +command given inside of the string in a sub-shell, and taking the +output as a string. This behavior is much the same as that of Unix +shells. + +Note that for security reasons, the input string is split into command +and arguments before string expansion is done. + +For performance reasons, we suggest that the use of back-quoted +strings be kept to a minimum. Executing external programs is +relatively expensive, and executing a large number of programs for +every request can quickly use all of the CPU time in a server. If you +believe that you need to execute many programs, we suggest finding +alternative ways to achieve the same result. In some cases, using a +real language may be sufficient. + +.IP /regex/im +These strings are valid only on the right-hand side of a comparison, +and then only when the comparison operator is "=~" or "!~". They are +regular expressions, as implemented by the local regular expression +library on the system. This is usually Posix regular expressions. + +The trailing 'i' is optional, and indicates that the regular +expression match should be done in a case-insensitive fashion. + +The trailing 'm' is also optional, and indicates that carrot '^' +and dollar '$' anchors should match on new lines as well as at the +start and end of the subject string. + +If the comparison operator is "=~", then parentheses in the regular +expression will define variables containing the matching text, as +described below in the ATTRIBUTE REFERENCES section. +.SH EXPANSIONS +Attributes are expanded using the ATTRIBUTE REFERENCE syntax +described above, and surrounding the reference with "%{...}" + +.DS + %{Attribute-Reference} +.DE + +The result will be a string which contains the value of the attribute +which was referenced, as a printable string. If the attribute does +not exist, the result will be an empty string. +.PP +Results of regular expression matches +.RS +If a regular expression match has previously been performed, then the +special variable %{0} will contain a copy of the matched portion of +the input string. The variables %{1} through %{32} will contain the +substring matches, starting from the left-most capture group, onwards. +If there are more than 32 capture groups, the additional results will +not be accessible. +If the server is built with libpcre, the results of named capture groups +are available using the "%{regex:capture group}" expansion. They will +also be accessible using the variables described above. +Every time a regular expression is evaluated, whether it matches or not, +the capture group values will be cleared. +.RE +.PP +Obtaining results from databases +.RS +It is useful to query a database for some information, and to use the +result in a condition. The following syntax will call a module, pass +it the given string, and replace the string expansion with the +resulting string returned from the module. + +.DS + %{module: string ...} +.DE + +The syntax of the string is module-specific. Please read the module +documentation for additional details. +.RE +.PP +Conditional Syntax +.RS +Conditional syntax similar to that used in Unix shells may also be +used. +.IP %{%{Foo}:-bar} +If %{Foo} has a value, returns that value. +.br +Otherwise, returns literal string "bar". +.IP %{%{Foo}:-%{Bar}} +If %{Foo} has a value, returns that value. +.br +Otherwise, returns the expansion of %{Bar}. + +These conditional expansions can be nested to almost any depth, such +as with %{%{One}:-%{%{Two}:-%{Three}}} +.RE +.PP +String lengths and arrays +.RS +Similar to a Unix shell, there are ways to reference string lengths, +and the second or more instance of an attribute in a list. If you +need more than this functionality, we suggest using a real language. +.IP %{strlen:string} +The number of characters in "string". If "string" does not exist, +then the length also does not exist, instead of being zero. + +The "string" is expanded before the length is taken. + +.IP %{integer:Attribute-Name} +The integer value of the Attribute-Name, instead of the enumerated +name. + +e.g. If a request contains "Service-Type = Login-User", the expansion +of %{integer:Service-Type} will yield "1". + +.IP %{hex:Attribute-Name} +The hex value of the Attribute-Name, as a series of hex digits. + +e.g. If a request contains "Framed-IP-Address = 127.0.0.1", the expansion +of %{hex:Framed-IP-Address} will yield "0x7f000001". + +.IP %{Attribute-Name[#]} +The number of instances of Attribute-Name. + +e.g. If a request contains "User-Name = bob", the expansion +of %{User-Name[#]} will yield "1". + +.IP %{Attribute-Name[*]} +All values of Attribute-Name, concatenated together with ',' as the +separator. + +.IP %{List-Name:[#]} +The number of attributes in the named list. + +.IP %{List-Name:[*]} +All values of attributes in the named-list, concatenated together with ',' +as the separator. Use the %{pairs:} xlat to get a list of attributes and +values. + +e.g. If a response contains "Reply-Message = 'Hello', Reply-Message = 'bob' +the expansion of "%{reply:Reply-Message[*]} will yield "Hello\\nbob" + +.SH ATTRIBUTE ASSIGNMENTS +The attribute lists described above may be edited by listing one or +more attributes in an "update" section. Once the attributes have been +defined, they may be referenced as described above in the ATTRIBUTE +REFERENCES section. + +The following syntax defines attributes in an "update" section. Each +attribute and value has to be all on one line in the configuration +file. There is no need for commas or semi-colons after the value. + +.DS + Attribute-Reference = value +.DE +.PP +Attribute Reference +.RS +The Attribute-Reference must be a reference (see above), using a name +previously defined in a dictionary. If an undefined name is used, the +server will return an error, and will not start. + +.RE +.IP Operators +The operator used to assign the value of the attribute may be one of +the following, with the given meaning. +.RS +.IP = +Add the attribute to the list, if and only if an attribute of the same +name is not already present in that list. +.IP := +Add the attribute to the list. If any attribute of the same name is +already present in that list, its value is replaced with the value of +the current attribute. +.IP += +Add the attribute to the tail of the list, even if attributes of the +same name are already present in the list. When the right hand side +of the expression resolves to multiple values, it means add all values +to the tail of the list. +.IP ^= +Add the attribute to the head of the list, even if attributes of the +same name are already present in the list. When the right hand side +of the expression resolves to multiple values, it means prepend all +values to the head of the list. +.RE +.PP +Enforcement and Filtering Operators +.RS +The following operators may also be used in addition to the ones +listed above. Their function is to perform enforcement or filtering +on attributes in a list. +.IP -= +Remove all matching attributes from the list. Both the attribute name +and value have to match in order for the attribute to be removed from +the list. +.IP == +Keep all matching attributes. Both the attribute name and value have +to match in order for the attribute to remain in the list. + +Note that this operator is very different than the '=' operator listed +above! +.IP != +Keep all attributes with matching name, and value not equal to the +given one. +.IP < +Keep all attributes having values less than the value +given here. Any larger value is replaced by the value given here. If +no attribute exists, it is added with the value given here, as with +"+=". +.IP <= +Keep all attributes having values less than, or equal to, the value +given here. Any larger value is replaced by the value given here. If +no attribute exists, it is added with the value given here, as with +"+=". +.IP > +Keep all attributes having values greater than the value +given here. Any smaller value is replaced by the value given here. If +no attribute exists, it is added with the value given here, as with +"+=". +.IP >= +Keep all attributes having values greater than, or equal to, the value +given here. Any smaller value is replaced by the value given here. If +no attribute exists, it is added with the value given here, as with +"+=". +.IP !* +Delete all occurrences of the named attribute, no matter what the +value. +.IP =~ +Keep all attributes having values which match the given regular +expression. If no attribute matches, nothing else is done. +.IP !~ +Keep all attributes having values which fail to match the given +regular expression. If no attribute matches, nothing else is done. +.RE +.IP Values +.br +The value can be an attribute reference, or an attribute-specific +string. + +When the value is an attribute reference, it must take the form of +"&Attribute-Name". The leading "&" signifies that the value is a +reference. The "Attribute-Name" is an attribute name, such as +"User-Name" or "request:User-Name". When an attribute reference is +used, both attributes must have the same data type. For example, +"User-Name := &NAS-Port" is invalid, because "User-Name" is a string, +and "NAS-Port" is an integer. + +We recommend using the form "Attribute-1 = &Attribute-2" for updates, +instead of "Attribute-1 = "%{Attribute-2}". The first version will +copy the attribute data, no matter what its form. The second +version will print the Attribute-2 to a string, and then parse it to +create the value for Attribute-1. This second version is slower +and more fragile than the first one. + +When the value is an attribute-specific string, it can be a string, +integer, IP address, etc. The value may be expanded as described +above in the DATA TYPES section, above. For example, specifying +"Framed-IP-Address = 127.0.0.1" will cause the "Framed-IP-Address" +attribute to be set to the IP address "127.0.0.1". However, using +"Framed-IP-Address := \"%{echo: 127.0.0.1}\"" will cause the "echo" +module to be run with a string "127.0.0.1". The output of the "echo" +module will then be parsed as an IP address, and placed into the +Framed-IP-Address attribute. + +This flexibility means that you can assign an IP address by specifying +it directly, or by having the address returned from a database query, +or by having the address returned as the output of a program that is +executed. + +When string values are finally assigned to an attribute, they can have a +maximum length of 253 characters. This limit is due in part to both +protocol and internal server requirements. That is, the strings in +the language can be nearly 8k in length, say for a long SQL query. +However, the output of that SQL query should be no more than 253 +characters in length. +.SH OTHER KEYWORDS +Other keywords in the language are taken from the names of modules +loaded by the server. These keywords are dependent on both the +modules, and the local configuration. + +Some use keywords that are defined in the default configuration file +are: +.IP fail +Cause the request to be treated as if a database failure had occurred. +.IP noop +Do nothing. This also serves as an instruction to the configurable +failover tracking that nothing was done in the current section. +.IP ok +Instructs the server that the request was processed properly. This +keyword can be used to over-ride earlier failures, if the local +administrator determines that the failures are not catastrophic. +.IP reject +Causes the request to be immediately rejected +.SH MODULE RETURN CODES +When a module is called, it returns one of the following codes to +"unlang", with the following meaning. + +.DS + notfound information was not found +.br + noop the module did nothing +.br + ok the module succeeded +.br + updated the module updated the request +.br + fail the module failed +.br + reject the module rejected the request +.br + userlock the user was locked out +.br + invalid the configuration was invalid +.br + handled the module has handled the request itself +.DE + +These return codes can be tested for in a condition, as described +above in the CONDITIONS section. + +See also the file doc/configurable_failover for additional methods of +trapping and modifying module return codes. +.SH FILES +/etc/raddb/radiusd.conf +.SH "SEE ALSO" +.BR radiusd.conf (5), +.BR dictionary (5) +.SH AUTHOR +Alan DeKok <aland@deployingradius.com> |