hackedteam/core-android-native

#include <stdlib.h>

#include "private.h"
#include "debug.h"
#include "log.h"

#include <sepol/policydb/policydb.h>

/* Construct a policydb from the supplied (data, len) pair */

int policydb_from_image(sepol_handle_t * handle,
            void *data, size_t len, policydb_t * policydb)
{

    policy_file_t pf;

    policy_file_init(&pf);
    pf.type = PF_USE_MEMORY;
    pf.data = data;
    pf.len = len;
    pf.handle = handle;

    if (policydb_read(policydb, &pf, 0)) {
        policydb_destroy(policydb);
        LOGD( "policy image is invalid");
        errno = EINVAL;
        return STATUS_ERR;
    }

    return STATUS_SUCCESS;
}

/* Write a policydb to a memory region, and return the (data, len) pair. */

int policydb_to_image(sepol_handle_t * handle,
              policydb_t * policydb, void **newdata, size_t * newlen)
{

    void *tmp_data = NULL;
    size_t tmp_len;
    policy_file_t pf;
    struct policydb tmp_policydb;

    /* Compute the length for the new policy image. */
    policy_file_init(&pf);
    pf.type = PF_LEN;
    pf.handle = handle;
    if (policydb_write(policydb, &pf)) {
        LOGD( "could not compute policy length");
        errno = EINVAL;
        goto err;
    }

    /* Allocate the new policy image. */
    pf.type = PF_USE_MEMORY;
    pf.data = malloc(pf.len);
    if (!pf.data) {
        LOGD( "out of memory");
        goto err;
    }

    /* Need to save len and data prior to modification by policydb_write. */
    tmp_len = pf.len;
    tmp_data = pf.data;

    /* Write out the new policy image. */
    if (policydb_write(policydb, &pf)) {
        LOGD( "could not write policy");
        errno = EINVAL;
        goto err;
    }

    /* Verify the new policy image. */
    pf.type = PF_USE_MEMORY;
    pf.data = tmp_data;
    pf.len = tmp_len;
    if (policydb_init(&tmp_policydb)) {
        LOGD( "Out of memory");
        errno = ENOMEM;
        goto err;
    }
    if (policydb_read(&tmp_policydb, &pf, 0)) {
        LOGD( "new policy image is invalid");
        errno = EINVAL;
        goto err;
    }
    policydb_destroy(&tmp_policydb);

    /* Update (newdata, newlen) */
    *newdata = tmp_data;
    *newlen = tmp_len;

    /* Recover */
    return STATUS_SUCCESS;

      err:
    LOGD( "could not create policy image");

    /* Recover */
    free(tmp_data);
    return STATUS_ERR;
}