From 5065830c9b51989d4e0d5b6a5c941fb6cda837ff Mon Sep 17 00:00:00 2001 From: Peter Palfrader Date: Wed, 30 Jan 2008 13:36:13 +0100 Subject: [PATCH] sha1: remove the result buffer alignment constraint * lib/sha1.c (set_uint32): New function. (sha1_read_ctx): Rewrite to remove the result buffer alignment constraint. (sha1_finish_ctx): Remove comment warning about alignment constraint. * lib/sha1.h: Likewise. --- ChangeLog | 9 +++++++++ lib/sha1.c | 30 +++++++++++++++++------------- lib/sha1.h | 13 ++++--------- 3 files changed, 30 insertions(+), 22 deletions(-) diff --git a/ChangeLog b/ChangeLog index 7929dcd85..e4224d161 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,12 @@ +2008-01-30 Peter Palfrader + + sha1: remove the result buffer alignment constraint + * lib/sha1.c (set_uint32): New function. + (sha1_read_ctx): Rewrite to remove the result buffer alignment + constraint. + (sha1_finish_ctx): Remove comment warning about alignment constraint. + * lib/sha1.h: Likewise. + 2008-01-30 Andreas Schwab Bruno Haible diff --git a/lib/sha1.c b/lib/sha1.c index 035f898c7..d9e99d862 100644 --- a/lib/sha1.c +++ b/lib/sha1.c @@ -67,28 +67,32 @@ sha1_init_ctx (struct sha1_ctx *ctx) ctx->buflen = 0; } -/* Put result from CTX in first 20 bytes following RESBUF. The result - must be in little endian byte order. +/* Copy the 4 byte value from v into the memory location pointed to by *cp, + If your architecture allows unaligned access this is equivalent to + * (uint32_t *) cp = v */ +void +set_uint32 (char *cp, uint32_t v) +{ + memcpy (cp, &v, 4); +} - IMPORTANT: On some systems it is required that RESBUF is correctly - aligned for a 32-bit value. */ +/* Put result from CTX in first 20 bytes following RESBUF. The result + must be in little endian byte order. */ void * sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf) { - ((uint32_t *) resbuf)[0] = SWAP (ctx->A); - ((uint32_t *) resbuf)[1] = SWAP (ctx->B); - ((uint32_t *) resbuf)[2] = SWAP (ctx->C); - ((uint32_t *) resbuf)[3] = SWAP (ctx->D); - ((uint32_t *) resbuf)[4] = SWAP (ctx->E); + char *r = resbuf; + set_uint32 (r + 0*4, SWAP (ctx->A)); + set_uint32 (r + 1*4, SWAP (ctx->B)); + set_uint32 (r + 2*4, SWAP (ctx->C)); + set_uint32 (r + 3*4, SWAP (ctx->D)); + set_uint32 (r + 4*4, SWAP (ctx->E)); return resbuf; } /* Process the remaining bytes in the internal buffer and the usual - prolog according to the standard and write the result to RESBUF. - - IMPORTANT: On some systems it is required that RESBUF is correctly - aligned for a 32-bit value. */ + prolog according to the standard and write the result to RESBUF. */ void * sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf) { diff --git a/lib/sha1.h b/lib/sha1.h index 9545f0b2b..9e55974ce 100644 --- a/lib/sha1.h +++ b/lib/sha1.h @@ -1,6 +1,7 @@ /* Declarations of functions and data types used for SHA1 sum library functions. - Copyright (C) 2000, 2001, 2003, 2005, 2006 Free Software Foundation, Inc. + Copyright (C) 2000, 2001, 2003, 2005, 2006, 2008 + Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the @@ -57,19 +58,13 @@ extern void sha1_process_bytes (const void *buffer, size_t len, /* Process the remaining bytes in the buffer and put result from CTX in first 20 bytes following RESBUF. The result is always in little endian byte order, so that a byte-wise output yields to the wanted - ASCII representation of the message digest. - - IMPORTANT: On some systems it is required that RESBUF be correctly - aligned for a 32 bits value. */ + ASCII representation of the message digest. */ extern void *sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf); /* Put result from CTX in first 20 bytes following RESBUF. The result is always in little endian byte order, so that a byte-wise output yields - to the wanted ASCII representation of the message digest. - - IMPORTANT: On some systems it is required that RESBUF is correctly - aligned for a 32 bits value. */ + to the wanted ASCII representation of the message digest. */ extern void *sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf); -- 2.11.0