-static uint8_t asn[15] = /* Object ID is 1.3.14.3.2.26 */
-{ 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03,
- 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14
-};
-
-MPI do_encode_md(const void *sha_buffer, unsigned nbits)
-{
- int nframe = (nbits + 7) / 8;
- uint8_t *frame, *fr_pt;
- int i = 0, n;
- size_t asnlen = DIM(asn);
- MPI a = NULL;
-
- if (SHA1_DIGEST_LENGTH + asnlen + 4 > nframe)
- pr_info("MPI: can't encode a %d bit MD into a %d bits frame\n",
- (int)(SHA1_DIGEST_LENGTH * 8), (int)nbits);
-
- /* We encode the MD in this way:
- *
- * 0 A PAD(n bytes) 0 ASN(asnlen bytes) MD(len bytes)
- *
- * PAD consists of FF bytes.
- */
- frame = kmalloc(nframe, GFP_KERNEL);
- if (!frame)
- return NULL;
- n = 0;
- frame[n++] = 0;
- frame[n++] = 1; /* block type */
- i = nframe - SHA1_DIGEST_LENGTH - asnlen - 3;
-
- if (i <= 1) {
- pr_info("MPI: message digest encoding failed\n");
- kfree(frame);
- return a;
- }
-
- memset(frame + n, 0xff, i);
- n += i;
- frame[n++] = 0;
- memcpy(frame + n, &asn, asnlen);
- n += asnlen;
- memcpy(frame + n, sha_buffer, SHA1_DIGEST_LENGTH);
- n += SHA1_DIGEST_LENGTH;
-
- i = nframe;
- fr_pt = frame;
-
- if (n != nframe) {
- printk
- ("MPI: message digest encoding failed, frame length is wrong\n");
- kfree(frame);
- return a;
- }
-
- a = mpi_alloc((nframe + BYTES_PER_MPI_LIMB - 1) / BYTES_PER_MPI_LIMB);
- if (a)
- mpi_set_buffer(a, frame, nframe, 0);
- kfree(frame);
-
- return a;
-}
-