Translating Between Labels and Strings

The label_to_str() and str_to_label() routines are used to translate between labels and strings. The following routine descriptions include the prototype declaration for each routine:

int label_to_str(const m_label_t *label, char **string, const m_label_str_t conversion_type, uint_t flags);

The label_to_str() routine translates a label, m_label_t, to a string. You can use this routine to translate a label into a string that hides the classification name. This format is suitable for storing in public objects. The calling process must dominate the label to be translated, or the process must have the sys_trans_label privilege.

See the label_to_str(3TSOL) man page.

The label_to_str() routine allocates memory for the translated string. The caller must free this memory by calling the free() routine.

See the free(3C) man page.

int str_to_label(const char *string, m_label_t **label, const m_label_type_t label_type, uint_t flags, int *error);

The str_to_label() routine translates a label string to a label, m_label_t. When you allocate an m_label_t structure, you must free the allocated memory by using the m_label_free() routine.

When you create a label by using the str_to_label() routine, you can set the label type to be a sensitivity label or a clearance label.

See the str_to_label(3TSOL) and m_label(3TSOL) man pages.

Readable Versions of Labels

The label_to_str() routine provides readable versions of labels. The M_LABEL conversion type returns a string that is classified at that label. The M_INTERNAL conversion type returns a string that is unclassified. The classified string version is typically used for displays, as in windows. The classified string might not be suitable for storage. Several conversion types are offered for printing purposes. All printing types show a readable string that is classified at the label that the string shows.

The conversion_type parameter controls the type of label conversion. The following are valid values for conversion_type, although not all types of conversion are valid for both level types:

• M_LABEL is a string of the label that is based on the type of label: sensitivity or clearance. This label string is classified at the level of the label and is therefore not safe for storing in a public object. For example, an M_LABEL string such as CONFIDENTIAL is not safe for storing in a public directory because the words in the label are often classified.

• M_INTERNAL is a string of an unclassified representation of the label. This string is safe for storing in a public object. For example, an M_INTERNAL string such as 0x0002-04-48 is safe for storing in an LDAP database.

• M_COLOR is a string that represents the color that the security administrator has associated with the label. The association between the label and the color is stored in the LOCAL DEFINITIONS section of the label_encodings file.

• PRINTER_TOP_BOTTOM is a string used as the top and the bottom label of banner and trailer pages.

• PRINTER_LABEL is a string used as the downgrade warning on the banner page.

• PRINTER_CAVEATS is a string used in the caveats section on the banner page.

• PRINTER_CHANNEL is a string used as the handling channels on the banner page.

Label Encodings File

The label_to_str() routine uses the label definitions in the label_encodings file. The encodings file is a text file that is maintained by the security administrator. The file contains site-specific label definitions and constraints. This file is kept in /etc/security/tsol/label_encodings. For information about the label_encodings file, see Solaris Trusted Extensions Label Administration, Compartmented Mode Workstation Labeling: Encodings Format, and the label_encodings(4) man page.