STR_TO_LABEL(3TSOL) Trusted Extensions Library Functions STR_TO_LABEL(3TSOL)


NAME


str_to_label - parse human readable strings to label

SYNOPSIS


cc [flag...] file... -ltsol [library...]


#include <tsol/label.h>

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


DESCRIPTION


The str_to_label() function is a simple function to parse human readable
strings into labels of the requested type.


The string argument is the string to parse. If string is the result of a
label_to_str() conversion of type M_INTERNAL, flags are ignored, and any
previously parsed label is replaced.


If *label is NULL, str_to_label() allocates resources for label and
initializes the label to the label_type that was requested before parsing
string.


If *label is not NULL, the label is a pointer to a mandatory label that
is the result of a previously parsed label and label_type is ignored. The
type that is used for parsing is derived from label for any type-
sensitive operations.


If flags is L_MODIFY_EXISTING, the parsed string can be used to modify
this label.


If flags is L_NO_CORRECTION, the previously parsed label is replaced and
the parsing algorithm does not attempt to infer missing elements from
string to compose a valid label.


If flags is L_DEFAULT, the previously parsed label is replaced and the
parsing algorithm makes a best effort to imply a valid label from the
elements of string.


If flags contains L_CHECK_AR logically OR-ed with another value, the
resulting label will be checked to ensure that it is within the
"Accreditation Range" of the DIA encodings schema. This flag is
interpreted only for MAC_LABEL label types.


The caller is responsible for freeing the allocated resources by calling
the m_label_free() function. label_type defines the type for a newly
allocated label. The label type can be:

MAC_LABEL
The string should be translated as a Mandatory Access
Control (MAC) label.


USER_CLEAR
The string should be translated as a label that represents
the least upper bound of the labels that the user is
allowed to access.


If error is NULL, do not return additional error information for EINVAL.
The calling process must have mandatory read access to label and human
readable string. Or the calling process must have the sys_trans_label
privilege.


The manifest constants ADMIN_HIGH and ADMIN_LOW are the human readable
strings that correspond to the Trusted Extensions policy admin_high and
admin_low label values. See labels(7).

RETURN VALUES


Upon successful completion, the str_to_label() function returns 0.
Otherwise, -1 is returned, errno is set to indicate the error, and error
provides additional information for EINVAL. Otherwise, error is a zero-
based index to the string parse failure point.

ERRORS


The str_to_label() function will fail if:

EINVAL
Invalid parameter. M_BAD_STRING indicates that string could
not be parsed. M_BAD_LABEL indicates that the label passed in
was in error. M_OUTSIDE_AR indicates that the resulting label
is not within the "Accreditation Range" specified in the DIA
encodings schema.


ENOTSUP
The system does not support label translations.


ENOMEM
The physical limits of the system are exceeded by size bytes
of memory which cannot be allocated.


ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Committed |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+
|Standard | See below. |
+--------------------+-----------------+


Parsing types that are relative to Defense Intelligence Agency (DIA)
encodings schema are Standard. Standard is specified in
label_encodings(5).

SEE ALSO


libtsol(3LIB), label_to_str(3TSOL), m_label(3TSOL), label_encodings(5),
attributes(7), labels(7)


Validating the Label Request Against the Printer's Label Range in Solaris
Trusted Extensions Developer's Guide

WARNINGS


A number of the parsing rules rely on the DIA label encodings schema. The
rules might not be valid for other label schemata.

NOTES


The functionality described on this manual page is available only if the
system is configured with Trusted Extensions.


June 15, 2009 STR_TO_LABEL(3TSOL)