Mercurial > hg > octave-lojdl > gnulib-hg
changeset 16861:660cb8105779
crypto: fix bug in large buffer handling
* lib/sha512.c (sha512_process_block):
Don't assume the buffer length is less than 2**32.
Here, the bug is present only in the rare case where the host does
not support uint64_t; use u64size to work around the problem.
* lib/u64.h (u64size): New macro.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Fri, 18 May 2012 14:33:54 -0700 |
parents | a3feab896112 |
children | e07426642eaa |
files | ChangeLog lib/sha512.c lib/u64.h |
diffstat | 3 files changed, 18 insertions(+), 2 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -9,6 +9,10 @@ * lib/sha1.c (sha1_process_block): * lib/sha256.c (sha256_process_block): Don't assume the buffer length is less than 2**32. + * lib/sha512.c (sha512_process_block): Likewise. + Here, the bug is present only in the rare case where the host does + not support uint64_t; use u64size to work around the problem. + * lib/u64.h (u64size): New macro. 2012-05-15 Pádraig Brady <P@draigBrady.com>
--- a/lib/sha512.c +++ b/lib/sha512.c @@ -485,12 +485,13 @@ u64 f = ctx->state[5]; u64 g = ctx->state[6]; u64 h = ctx->state[7]; + u64 len64 = u64size (len); /* First increment the byte count. FIPS PUB 180-2 specifies the possible length of the file up to 2^128 bits. Here we only compute the number of bytes. Do a double word increment. */ - ctx->total[0] = u64plus (ctx->total[0], u64lo (len)); - if (u64lt (ctx->total[0], u64lo (len))) + ctx->total[0] = u64plus (ctx->total[0], len64); + if (u64lt (ctx->total[0], len64)) ctx->total[1] = u64plus (ctx->total[1], u64lo (1)); #define S0(x) u64xor (u64rol(x, 63), u64xor (u64rol (x, 56), u64shr (x, 7)))
--- a/lib/u64.h +++ b/lib/u64.h @@ -30,6 +30,7 @@ # define u64hilo(hi, lo) ((u64) (((u64) (hi) << 32) + (lo))) # define u64init(hi, lo) u64hilo (hi, lo) # define u64lo(x) ((u64) (x)) +# define u64size(x) u64lo (x) # define u64lt(x, y) ((x) < (y)) # define u64and(x, y) ((x) & (y)) # define u64or(x, y) ((x) | (y)) @@ -72,6 +73,16 @@ return r; } +/* Return a u64 value representing SIZE. */ +static inline u64 +u64size (size_t size) +{ + u64 r; + r.hi = size >> 31 >> 1; + r.lo = size; + return r; +} + /* Return X < Y. */ static inline int u64lt (u64 x, u64 y)