PRIV_STR_TO_SET(3C) Standard C Library Functions PRIV_STR_TO_SET(3C)


NAME


priv_str_to_set, priv_set_to_str, priv_getbyname, priv_getbynum,
priv_getsetbyname, priv_getsetbynum, priv_gettext - privilege name
functions

SYNOPSIS


#include <priv.h>

priv_set_t *priv_str_to_set(const char *buf, const char *sep,
const char **endptr);


char *priv_set_to_str(const priv_set_t *set, char sep, int flag);


int priv_getbyname(const char *privname);


const char *priv_getbynum(int privnum);


int priv_getsetbyname(const char *privsetname);


const char *priv_getsetbynum(int privname);


char *priv_gettext(const char *privname);


DESCRIPTION


The priv_str_to_set() function maps the privilege specification in buf to
a privilege set. It returns a privilege set on success or NULL on
failure. If an error occurs when parsing the string, a pointer to the
remainder of the string is stored in the object pointed to by endptr,
provided that endptr is not a null pointer. If an error occurs when
allocating memory, errno is set and the object pointed to by endptr is
set to the null pointer, provided that endptr is not a null pointer.


The application is responsible for freeing the returned privilege set
using priv_freeset(3C).


A privilege specification should contain one or more privilege names,
separated by characters in sep using the same algorithm as strtok(3C).
Privileges can optionally be preceded by a dash (-) or an exclamation
mark (!), in which case they are excluded from the resulting set. The
special strings "none" for the empty set, "all" for the set of all
privileges, "zone" for the set of all privileges available within the
caller's zone, and "basic" for the set of basic privileges are also
recognized. Set specifications are interpreted from left to right.


The priv_set_to_str() function converts the privilege set to a sequence
of privileges separated by sep, returning the a pointer to the
dynamically allocated result. The application is responsible for freeing
the memory using free(3C).


To maintain future compatibility, the "basic" set of privileges is
included as "basic,!missing_basic_priv1,...". When further currently
unprivileged operations migrate to the basic privilege set, the
conversion back of the result with priv_str_to_set() includes the
additional basic privileges, guaranteeing that the resulting privilege
set carries the same privileges. This behavior is the default and is
equivalent to specifying a flag argument of PRIV_STR_PORT. When
specifying a flag argument of PRIV_STR_LIT, the result does not treat
basic privileges differently and the privileges present are all literally
presented in the output. A flag argument of PRIV_STR_SHORT attempts to
arrive at the shortest output, using the tokens "basic", "zone", "all",
and negated privileges. This output is most useful for trace output.


The priv_getbyname() and priv_getsetbyname() functions map privilege
names and privilege set names to numbers. The numbers returned are valid
for the current kernel instance only and could change at the next boot.
Only the privilege names should be committed to persistent storage. The
numbers should not be committed to persistent storage. Both functions
return -1 on error, setting errno to EINVAL.


The priv_getbynum() and priv_getsetbynum() functions map privileges
numbers to names. The strings returned point to shared storage that
should not be modified and is valid for the lifetime of the process. Both
functions return NULL on error, setting errno to EINVAL.


The priv_gettext() function returns a pointer to a string consisting of
one or more newline-separated lines of text describing the privilege. The
text is localized using {LC_MESSAGES}. The application is responsible for
freeing the memory returned.


These functions pick up privileges allocated during the lifetime of the
process using priv_getbyname(9F) by refreshing the internal data
structures when necessary.

RETURN VALUES


Upon successful completion, priv_str_to_set() and priv_set_to_str()
return a non-null pointer to allocated memory that should be freed by the
application using the appropriate functions when it is no longer
referenced.


The priv_getbynum() and priv_getsetbynum() functions return non-null
pointers to constant memory that should not be modified or freed by the
application. Otherwise, NULL is returned and errno is set to indicate the
error.


Upon successful completion, priv_getbyname() and priv_getsetbyname()
return a non-negative integer. Otherwise, -1 is returned and errno is set
to indicate the error.


Upon successful completion, priv_gettext() returns a non-null value. It
returns NULL if an error occurs or no descriptive text for the specified
privilege can be found.

ERRORS


The priv_str_to_set() and priv_set_to_str() functions will fail if:

ENOMEM
The physical limits of the system are exceeded by the memory
allocation needed to hold a privilege set.


EAGAIN
There is not enough memory available to allocate sufficient
memory to hold a privilege set, but the application could try
again later.


All of these functions will fail if:

EINVAL
One or more of the arguments is invalid.


EXAMPLES


Example 1: List all the sets and privileges defined in the system.




The following example lists all the sets and privileges defined in the
system.


#include <priv.h>
#include <stdio.h>

/* list all the sets and privileges defined in the system */

const char *name;
int i;

printf("Each process has the following privilege sets:\n");
for (i = 0; (name = priv_getsetbynum(i++)) != NULL; )
printf("\t%s\n", name);

printf("Each set can contain the following privileges:\n");
for (i = 0; (name = priv_getbynum(i++)) != NULL; )
printf("\t%s\n", name);


ATTRIBUTES


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


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Evolving |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+

SEE ALSO


free(3C), priv_set(3C), attributes(5), privileges(5), priv_getbyname(9F)


November 26, 2017 PRIV_STR_TO_SET(3C)