blob: fb8c266775c1ed83ba40bbc31da0695392d201b8 [file] [log] [blame]
/*
* Generalized labeling frontend for userspace object managers.
*
* Author : Eamon Walsh <ewalsh@epoch.ncsc.mil>
*/
#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <selinux/selinux.h>
#include "callbacks.h"
#include "label_internal.h"
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
typedef int (*selabel_initfunc)(struct selabel_handle *rec,
const struct selinux_opt *opts,
unsigned nopts);
static selabel_initfunc initfuncs[] = {
&selabel_file_init,
NULL,
NULL,
NULL,
&selabel_property_init,
};
/*
* Validation functions
*/
static inline int selabel_is_validate_set(const struct selinux_opt *opts,
unsigned n)
{
while (n--)
if (opts[n].type == SELABEL_OPT_VALIDATE)
return !!opts[n].value;
return 0;
}
int selabel_validate(struct selabel_handle *rec,
struct selabel_lookup_rec *contexts)
{
int rc = 0;
if (!rec->validating || contexts->validated)
goto out;
rc = selinux_validate(&contexts->ctx_raw);
if (rc < 0)
goto out;
contexts->validated = 1;
out:
return rc;
}
/*
* Public API
*/
struct selabel_handle *selabel_open(unsigned int backend,
const struct selinux_opt *opts,
unsigned nopts)
{
struct selabel_handle *rec = NULL;
if (backend >= ARRAY_SIZE(initfuncs)) {
errno = EINVAL;
goto out;
}
if (initfuncs[backend] == NULL)
goto out;
rec = (struct selabel_handle *)malloc(sizeof(*rec));
if (!rec)
goto out;
memset(rec, 0, sizeof(*rec));
rec->backend = backend;
rec->validating = selabel_is_validate_set(opts, nopts);
if ((*initfuncs[backend])(rec, opts, nopts)) {
free(rec->spec_file);
free(rec);
rec = NULL;
}
out:
return rec;
}
static struct selabel_lookup_rec *
selabel_lookup_common(struct selabel_handle *rec,
const char *key, int type)
{
struct selabel_lookup_rec *lr;
lr = rec->func_lookup(rec, key, type);
if (!lr)
return NULL;
return lr;
}
int selabel_lookup(struct selabel_handle *rec, char **con,
const char *key, int type)
{
struct selabel_lookup_rec *lr;
lr = selabel_lookup_common(rec, key, type);
if (!lr)
return -1;
*con = strdup(lr->ctx_raw);
return *con ? 0 : -1;
}
bool selabel_partial_match(struct selabel_handle *rec, const char *key)
{
if (!rec->func_partial_match) {
/*
* If the label backend does not support partial matching,
* then assume a match is possible.
*/
return true;
}
return rec->func_partial_match(rec, key);
}
int selabel_lookup_best_match(struct selabel_handle *rec, char **con,
const char *key, const char **aliases, int type)
{
struct selabel_lookup_rec *lr;
if (!rec->func_lookup_best_match) {
errno = ENOTSUP;
return -1;
}
lr = rec->func_lookup_best_match(rec, key, aliases, type);
if (!lr)
return -1;
*con = strdup(lr->ctx_raw);
return *con ? 0 : -1;
}
enum selabel_cmp_result selabel_cmp(struct selabel_handle *h1,
struct selabel_handle *h2)
{
if (!h1->func_cmp || h1->func_cmp != h2->func_cmp)
return SELABEL_INCOMPARABLE;
return h1->func_cmp(h1, h2);
}
void selabel_close(struct selabel_handle *rec)
{
rec->func_close(rec);
free(rec->spec_file);
free(rec);
}
void selabel_stats(struct selabel_handle *rec)
{
rec->func_stats(rec);
}