GETEXECATTR(3SECDB) Security Attributes Database Library Functions


NAME


getexecattr, free_execattr, setexecattr, endexecattr, getexecuser,
getexecprof, match_execattr - get execution profile entry

SYNOPSIS


cc [ flag... ] file... -lsecdb -lsocket -lnsl [ library... ]
#include <exec_attr.h>
#include <secdb.h>

execattr_t *getexecattr(void);


void free_execattr(execattr_t *ep);


void setexecattr(void);


void endexecattr(void);


execattr_t *getexecuser(const char *username, const char *type,
const char *id, int search_flag);


execattr_t *getexecprof(const char *profname, const char *type,
const char *id, int search_flag);


execattr_t *match_execattr(execattr_t *ep, char *profname,
char *type, char *id);


DESCRIPTION


The getexecattr() function returns a single exec_attr(4) entry. Entries
can come from any of the sources specified in the nsswitch.conf(4) file.


Successive calls to getexecattr() return either successive exec_attr
entries or NULL. Because getexecattr() always returns a single entry, the
next pointer in the execattr_t data structure points to NULL.


The internal representation of an exec_attr entry is an execattr_t
structure defined in <exec_attr.h> with the following members:

char *name; /* name of the profile */
char *policy; /* policy under which the attributes are */
/* relevant*/
char *type; /* type of profile */
char *res1; /* reserved for future use */
char *res2; /* reserved for future use */
char *id; /* unique identifier */
kva_t *attr; /* attributes */
struct execattr_s *next; /* optional pointer to next profile */


The free_execattr() function releases memory. It follows the next
pointers in the execattr_t structure so that the entire linked list is
released.


The setexecattr() function "rewinds" to the beginning of the enumeration
of exec_attr entries. Calls to getexecuser() can leave the enumeration in
an indeterminate state. Therefore, setexecattr() should be called before
the first call to getexecattr().


The endexecattr() function can be called to indicate that exec_attr
processing is complete; the library can then close any open exec_attr
file, deallocate any internal storage, and so forth.


The getexecuser() function returns a linked list of entries that match
the type and id arguments and have a profile that has been assigned to
the user specified by username, as described in passwd(4). Profiles for
the user are obtained from the list of default profiles in
/etc/security/policy.conf (see policy.conf(4)) and the user_attr(4)
database. Only entries in the name service scope for which the
corresponding profile entry is found in the prof_attr(4) database are
returned.


The getexecprof() function returns a linked list of entries that match
the type and id arguments and have the profile specified by the profname
argument. Only entries in the name service scope for which the
corresponding profile entry is found in the prof_attr database are
returned.


Using getexecuser() and getexecprof(), programmers can search for any
type argument, such as the manifest constant KV_COMMAND. The arguments
are logically AND-ed together so that only entries exactly matching all
of the arguments are returned. Wildcard matching applies if there is no
exact match for an ID. Any argument can be assigned the NULL value to
indicate that it is not used as part of the matching criteria. The
search_flag controls whether the function returns the first match
(GET_ONE), setting the next pointer to NULL or all matching entries
(GET_ALL), using the next pointer to create a linked list of all entries
that meet the search criteria. See EXAMPLES.


Once a list of entries is returned by getexecuser() or getexecprof(), the
convenience function match_execattr() can be used to identify an
individual entry. It returns a pointer to the individual element with the
same profile name (profname), type name (type), and id. Function
parameters set to NULL are not used as part of the matching criteria. In
the event that multiple entries meet the matching criteria, only a
pointer to the first entry is returned. The kva_match(3SECDB) function
can be used to look up a key in a key-value array.

RETURN VALUES


Those functions returning data only return data related to the active
policy. The getexecattr() function returns a pointer to a execattr_t if
it successfully enumerates an entry; otherwise it returns NULL,
indicating the end of the enumeration.

USAGE


The getexecattr(), getexecuser(), and getexecprof() functions all
allocate memory for the pointers they return. This memory should be
deallocated with the free_execattr() call. The match_execattr() function
does not allocate any memory. Therefore, pointers returned by this
function should not be deallocated.


Individual attributes may be referenced in the attr structure by calling
the kva_match(3SECDB) function.

EXAMPLES


Example 1: Find all profiles that have the ping command.



if ((execprof=getexecprof(NULL, KV_COMMAND, "/usr/sbin/ping",
GET_ONE)) == NULL) {
/* do error */
}


Example 2: Find the entry for the ping command in the Network


Administration Profile.

if ((execprof=getexecprof("Network Administration", KV_COMMAND,
"/usr/sbin/ping", GET_ALL))==NULL) {
/* do error */
}


Example 3: Tell everything that can be done in the Filesystem Security


profile.

if ((execprof=getexecprof("Filesystem Security", NULL, NULL,
GET_ALL))==NULL)) {
/* do error */
}


Example 4: Tell if the tar utility is in a profile assigned to user


wetmore. If there is no exact profile entry, the wildcard (*), if
defined, is returned.

if ((execprof=getexecuser("wetmore", KV_COMMAND, "/usr/bin/tar",
GET_ONE))==NULL) {
/* do error */
}


FILES


/etc/nsswitch.conf
configuration file lookup information for
the name service switch


/etc/user_attr
extended user attributes


/etc/security/exec_attr
execution profiles


/etc/security/policy.conf
policy definitions


/etc/security/prof_attr
profile information


ATTRIBUTES


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


+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT-Level | MT-Safe |
+---------------+-----------------+

SEE ALSO


getauthattr(3SECDB), getprofattr(3SECDB), getuserattr(3SECDB),
kva_match(3SECDB), exec_attr(4), passwd(4), policy.conf(4), prof_attr(4),
user_attr(4), attributes(5)


August 13, 2018 GETEXECATTR(3SECDB)