[PATCH] sha256: do not artificially restrict buffer length to be < 2^32

[Jim Meyering]

Tom's patch helped me spot a bug in sha256.h.
The buflen member there has type uint32_t,
yet we store in it values of type size_t.
Obviously that makes a difference for values larger than UINTMAX.

Here's the patch:


>From ef5f9af1559b043755d0af03c31676cd66fa40e7 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Mon, 26 May 2008 19:29:50 +0200
Subject: [PATCH] sha256: do not artificially restrict buffer length to be < 2^32

* lib/sha256.h (struct sha256_ctx) [buflen]: Change type from
uint32_t to size_t.
* lib/sha256.c (sha256_conclude_ctx): Change type of a local
to match.

---
 ChangeLog    |    6 ++++++
 lib/sha256.c |    2 +-
 lib/sha256.h |    2 +-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 9aea4e6..a72b682 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2008-05-26  Jim Meyering  <address@hidden>

+       sha256: do not artificially restrict buffer length to be < 2^32
+       * lib/sha256.h (struct sha256_ctx) [buflen]: Change type from
+       uint32_t to size_t.
+       * lib/sha256.c (sha256_conclude_ctx): Change type of a local
+       to match.
+
        avoid unaligned access errors, e.g., on sparc
        * lib/sha512.c (sha512_conclude_ctx): Use set_uint64 rather than
        direct access through a possibly-unaligned uint64* pointer.
diff --git a/lib/sha256.c b/lib/sha256.c
index a1362ca..0ad9444 100644
--- a/lib/sha256.c
+++ b/lib/sha256.c
@@ -126,7 +126,7 @@ static void
 sha256_conclude_ctx (struct sha256_ctx *ctx)
 {
   /* Take yet unprocessed bytes into account.  */
-  uint32_t bytes = ctx->buflen;
+  size_t bytes = ctx->buflen;
   size_t size = (bytes < 56) ? 64 / 4 : 64 * 2 / 4;

   /* Now count remaining bytes.  */
diff --git a/lib/sha256.h b/lib/sha256.h
index c35d6c1..3aa1ce9 100644
--- a/lib/sha256.h
+++ b/lib/sha256.h
@@ -27,7 +27,7 @@ struct sha256_ctx
   uint32_t state[8];

   uint32_t total[2];
-  uint32_t buflen;
+  size_t buflen;
   uint32_t buffer[32];
 };

--
1.5.5.1.383.g8078b