From 215b01bba8bc662d35f72b084700b192d367dfb4 Mon Sep 17 00:00:00 2001 From: Bartlomiej Sieka Date: Tue, 22 Apr 2008 12:27:56 +0200 Subject: Add support for calculating hashes with watchdog triggering Implement watchodg-aware variants of hash calculation functions: - crc32_wd() - md5_wd() - sha1_csum_wd() The above functions calculate the hash of the input buffer in chunks, triggering the watchdog after processing each chunk. The chunk size is given as a function call parameter. Signed-off-by: Bartlomiej Sieka --- lib_generic/md5.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) (limited to 'lib_generic/md5.c') diff --git a/lib_generic/md5.c b/lib_generic/md5.c index 3cee431..20178b8 100644 --- a/lib_generic/md5.c +++ b/lib_generic/md5.c @@ -272,3 +272,39 @@ md5 (unsigned char *input, int len, unsigned char output[16]) MD5Update(&context, input, len); MD5Final(output, &context); } + + +/* + * Calculate and store in 'output' the MD5 digest of 'len' bytes at 'input'. + * 'output' must have enough space to hold 16 bytes. If 'chunk' Trigger the + * watchdog every 'chunk_sz' bytes of input processed. + */ +void +md5_wd (unsigned char *input, int len, unsigned char output[16], + unsigned int chunk_sz) +{ + struct MD5Context context; +#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG) + unsigned char *end, *curr; + int chunk; +#endif + + MD5Init(&context); + +#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG) + curr = input; + end = input + len; + while (curr < end) { + chunk = end - curr; + if (chunk > chunk_sz) + chunk = chunk_sz; + MD5Update(&context, curr, chunk); + curr += chunk; + WATCHDOG_RESET (); + } +#else + MD5Update(&context, input, len); +#endif + + MD5Final(output, &context); +} -- cgit v1.1