void *vb2_workbuf_realloc(struct vb2_workbuf *wb,
uint32_t oldsize,
uint32_t newsize)
{
/*
* Just free and allocate to update the size. No need to move/copy
* memory, since the new pointer is guaranteed to be the same as the
* old one. The new allocation can fail, if the new size is too big.
*/
vb2_workbuf_free(wb, oldsize);
return vb2_workbuf_alloc(wb, newsize);
}
int vb2_verify_data(const uint8_t *data,
uint32_t size,
struct vb2_signature *sig,
const struct vb2_public_key *key,
const struct vb2_workbuf *wb)
{
struct vb2_workbuf wblocal = *wb;
struct vb2_digest_context *dc;
uint8_t *digest;
uint32_t digest_size;
int rv;
if (sig->data_size > size) {
VB2_DEBUG("Data buffer smaller than length of signed data.\n");
return VB2_ERROR_VDATA_NOT_ENOUGH_DATA;
}
/* Digest goes at start of work buffer */
digest_size = vb2_digest_size(key->hash_alg);
if (!digest_size)
return VB2_ERROR_VDATA_DIGEST_SIZE;
digest = vb2_workbuf_alloc(&wblocal, digest_size);
if (!digest)
return VB2_ERROR_VDATA_WORKBUF_DIGEST;
/* Hashing requires temp space for the context */
dc = vb2_workbuf_alloc(&wblocal, sizeof(*dc));
if (!dc)
return VB2_ERROR_VDATA_WORKBUF_HASHING;
rv = vb2_digest_init(dc, key->hash_alg);
if (rv)
return rv;
rv = vb2_digest_extend(dc, data, sig->data_size);
if (rv)
return rv;
rv = vb2_digest_finalize(dc, digest, digest_size);
if (rv)
return rv;
vb2_workbuf_free(&wblocal, sizeof(*dc));
return vb2_verify_digest(key, sig, digest, &wblocal);
}
