label_encodings(4) (Solaris Trusted Extensions Reference Manual)

Solaris Trusted Extensions Reference Manual

label_encodings(4)

NAME

label_encodings – label encodings file

Synopsis

/etc/security/tsol/label_encodings

Interface Level

This file is part of the Defense Intelligence Agency (DIA) Mandatory Access Control (MAC) policy. This file might not be applicable to other Mandatory policies that might be developed for future releases of Solaris Trusted Extensions software.

Parts of the label_encodings file are considered standard and are controlled by Defense Intelligence Agency document DDS-2600-6216-93, Compartmented Mode Workstation Labeling: Encodings Format, September 1993. Of that standard, the parts that refer to the INFORMATION LABELS: and NAME INFORMATION LABELS: sections are Obsolete. However, the INFORMATION LABELS: section must be present and syntactically correct. It is ignored. The NAME INFORMATION LABELS: section is optional. If present, it is ignored but must be syntactically correct.

The following values in the optional LOCAL DEFINITIONS: section are obsolete. These values might only affect the obsolete bltos(3TSOL) functions, and might be ignored by the label_to_str(3TSOL) replacement function:

ADMIN LOW NAME=

ADMIN HIGH NAME=

DEFAULT LABEL VIEW IS EXTERNAL

DEFAULT LABEL VIEW IS INTERNAL

DEFAULT FLAGS=

FORCED FLAGS=

CLASSIFICATION NAME=

COMPARTMENTS NAME=

Description

The label_encodings file is a standard encodings file of security labels that are used to control the conversion of human-readable labels into an internal format, the conversion from the internal format to a human-readable canonical form, and the construction of banner pages for printed output. On a Solaris Trusted Extensions system, the label_encodings file is protected at the label admin_high. The file should be edited and checked by the security administrator using the Check Label Encodings action in the System_Admin folder in the Application Manager.

Extended Description

In addition to the required sections of the label encodings file that are described in Compartmented Mode Workstation Labeling: Encodings Format, a Solaris Trusted Extensions system accepts optional local extensions. These extensions provide various translation options and an association between character-coded color names and sensitivity labels.

The optional local extensions section starts with the LOCAL DEFINITIONS: keyword and is followed by zero or more of the following unordered statements:

DEFAULT USER SENSITIVITY LABEL= sensitivity label: This option specifies the sensitivity label to use as the user's minimum sensitivity label if none is defined for the user in the administrative databases. The default value is the MINIMUM SENSITIVITY LABEL= value from the ACCREDITATION RANGE: section of the label encodings file.
DEFAULT USER CLEARANCE= clearance: This option specifies the clearance to use as the user's clearance if none is defined for the user in the administrative databases. The default value is the MINIMUM CLEARANCE= value from the ACCREDITATION RANGE: section of the label encodings file.

The final part of the LOCAL DEFINITIONS: section defines the character-coded color names to be associated with various words, sensitivity labels, or classifications. This section supports the str_to_label(3TSOL) function. It consists of the COLOR NAMES: keyword and is followed by zero or more color-to-label assignments. Each statement has one of the following two syntaxes:

word= word value; color= color value;

label= label value; color= color value;

where color value is a character-coded color name to be associated with the word word value, or with the sensitivity label label value, or with the classification label value.

The character-coded color name color value for a label is determined by the order of entries in the COLOR NAMES: section that make up the label. If a label contains a word word value that is specified in this section, the color value of the label is the one associated with the first word value specified. If no specified word word value is contained in the label, the color value is the one associated with an exact match of a label value. If there is no exact match, the color value is the one associated with the first specified label value whose classification matches the classification of the label.

Examples

Example 1 A Sample LOCAL DEFINITIONS: Section

LOCAL DEFINITIONS:
     
DEFAULT USER SENSITIVITY LABEL= C A;
DEFAULT USER CLEARANCE LABEL= S ABLE;

COLOR NAMES:

label= Admin_Low;    color= Pale Blue;
label= unclassified; color= light grey;
word= Project A;     color= bright blue;
label= c;            color= sea foam green;
label= secret;       color= #ff0000;       * Hexadecimal RGB value
word= Hotel;         color= Lavender;
word= KeLO;          color= red;
label= TS;           color= khaki;
label= TS Elephant;  color= yellow;
label= Admin_High;   color= shocking pink;

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Availability	SUNWtsr
Stability Level	Mixed. See `INTERFACE LEVEL`, above.

Files

/etc/security/tsol/label_encodings: The label encodings file contains the classification names, words, constraints, and values for the defined labels of this system. It is protected at the label admin_high.

Diagnostics

The following diagnostics are in addition to those found in Appendix A of Compartmented Mode Workstation Labeling: Encodings Format:

Can't allocate NNN bytes for color names table.: The system cannot dynamically allocate the memory it needs to process the COLOR NAMES: section.
Can't allocate NNN bytes for color table entry.: The system cannot dynamically allocate the memory it needs to process a Color Table entry.
Can't allocate NNN bytes for color word entry.: The system cannot dynamically allocate the memory it needs to process a Color Word entry.
Can't allocate NNN bytes for DEFAULT USER CLEARANCE.: The system cannot dynamically allocate the memory it needs to process the DEFAULT USER CLEARANCE.
Can't allocate NNN bytes for DEFAULT USER SENSITIVITY LABEL.: The system cannot dynamically allocate the memory it needs to process the DEFAULT USER SENSITIVITY LABEL.
DEFAULT USER CLEARANCE= XXX is not in canonical form. Is YYY what is intended?: This error occurs if the clearance specified, while understood, is not in canonical form. This additional canonicalization check ensures that no errors are made in specifying the clearance.
DEFAULT USER SENSITIVITY LABEL= XXX is not in canonical form. Is YYY what is intended?: This error occurs if a sensitivity label specified, while understood, is not in canonical form. This additional canonicalization check ensures that no errors are made in specifying the sensitivity label.
Duplicate DEFAULT USER CLEARANCE= ignored.: More than one DEFAULT USER CLEARANCE= option was encountered. All but the first are ignored.
Duplicate DEFAULT USER SENSITIVITY LABEL= ignored.: More than one DEFAULT USER SENSITIVITY LABEL= option was encountered. All but the first are ignored.
End of File not found where expected. Found instead: XXX.: The noted extraneous text was found when the end of label encodings file was expected.
End of File or LOCAL DEFINITIONS: not found. Found instead: XXX.: The noted extraneous text was found when the LOCAL DEFINITIONS: section or end of label encodings file was expected.
Found color XXX without associated label.: The color XXX was found, however it had no label or word associated with it.
Invalid color label XXX.: The label XXX cannot be parsed.
Invalid DEFAULT USER CLEARANCE XXX.: The DEFAULT USER CLEARANCE XXX cannot be parsed.
Invalid DEFAULT USER SENSITIVITY LABEL XXX.: The DEFAULT USER SENSITIVITY LABEL XXX cannot be parsed.
Label preceding XXX did not have a color specification.: A label or word was found without a matching color name.
Word XXX not found as a valid Sensitivity Label word.: The word XXX was not found as a valid word for a sensitivity label.

Warnings

Creation of and modification to the label encodings file should only be undertaken with a thorough understanding not only of the concepts in Compartmented Mode Workstation Labeling: Encodings Format, but also of the details of the local labeling requirements.

The following warnings are paraphrased from Compartmented Mode Workstation Labeling: Encodings Format.

Take extreme care when modifying a label encodings file that is already loaded and running on a Solaris Trusted Extensions system. Once the system runs with the label encodings file, many objects are labeled with sensitivity labels that are well formed with respect to the loaded label encodings file. If the label encodings file is subsequently changed, it is possible that the existing labels will no longer be well-formed. Changing the bit patterns associated with words causes existing objects whose labels contain the words to have possibly invalid labels. Raising the minimum classification or lowering the maximum classification that is associated with words will likely cause existing objects whose labels contain the words to no longer be well-formed.

Changes to a current encodings file that has already been used should be limited only to adding new classifications or words, changing the names of existing words, or modifying the local extensions. As described in Compartmented Mode Workstation Labeling: Encodings Format, it is important to reserve extra inverse bits when the label encodings file is first created to allow for later expansion of the label encodings file to incorporate new inverse words. If an inverse word is added that does not use reserved inverse bits, all existing objects on the system will erroneously have labels that include the new inverse word.

Notes

This file is only meaningful for the DIA MAC policy. Parts of it are obsolete and retained for ease of porting. The obsolete parts might be removed in a future Solaris Trusted Extensions release.

Defining the label encodings file is a three-step process. First, the set of human-readable labels to be represented must be identified and understood. The definition of this set includes the list of classifications and other words that are used in the human-readable labels, relations between and among the words, classification restrictions that are associated with use of each word, and intended use of the words in mandatory access control and labeling system output. Next, this definition is associated with an internal format of integers, bit patterns, and logical relationship statements. Finally, a label encodings file is created. The Compartmented Mode Workstation Labeling: Encodings Format document describes the second and third steps, and assumes that the first has already been performed.

SunOS 5.10 Last Revised 31 May 2006