linux-sunxi/u-boot-sunxi
1
0
Fork 0
mirror of https://github.com/linux-sunxi/u-boot-sunxi.git synced 2024-02-12 11:16:03 +08:00
Code Issues Projects Releases Wiki Activity

rsa: Verify RSA padding programatically

Browse Source 
Padding verification was done against static SHA/RSA pair arrays which
take up a lot of static memory, are mostly 0xff, and cannot be reused
for additional SHA/RSA pairings. The padding can be easily computed
according to PKCS#1v2.1 as:

  EM = 0x00 || 0x01 || PS || 0x00 || T

where PS is (emLen - tLen - 3) octets of 0xff and T is DER encoding
of the hash.

Store DER prefix in checksum_algo and create rsa_verify_padding
function to handle verification of a message for any SHA/RSA pairing.

Signed-off-by: Andrew Duda <aduda@meraki.com>
Signed-off-by: aduda <aduda@meraki.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Andrew Duda
2016-11-08 18:53:40 +00:00
committed by Tom Rini
parent 5300a4f933
commit da29f2991d
9 changed files with 61 additions and 131 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
include/u-boot/sha256.h
View File

@ -2,6 +2,9 @@
#define _SHA256_H
#define SHA256_SUM_LEN 32
#define SHA256_DER_LEN 19
extern const uint8_t sha256_der_prefix[];
/* Reset watchdog each time we process this many bytes */
#define CHUNKSZ_SHA256 (64 * 1024)