[Downloads] Rework how hashes are calculated for download files.

crypto/third_party/nss/sha512.cc

 /*
  * sha512.c - implementation of SHA256, SHA384 and SHA512
  *
  * ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
  * 1.1 (the "License"); you may not use this file except in compliance with
  * the License. You may obtain a copy of the License at
  * http://www.mozilla.org/MPL/
@@ skipping 453 matching lines @@
     BYTESWAP4(H[5]);
     BYTESWAP4(H[6]);
     BYTESWAP4(H[7]);
 #endif
     padLen = PR_MIN(SHA256_LENGTH, maxDigestLen);
     memcpy(digest, H, padLen);
     if (digestLen)
         *digestLen = padLen;
 }
 
+void SHA256_Clone(SHA256Context* dest, SHA256Context* src) {
+  memcpy(dest, src, sizeof *dest);
+}

[davidben, 2016/03/08 22:12:03]

Nit: Probably this should be mirroring the original style? *shrug* Hopefully the
file also isn't long for this world.

[asanka, 2016/03/10 16:48:09]

Done. I blame 'git cl format' for this one, since I'm pretty sure I just copied
the function out of the #if 0 block below.

+
 /* Comment out unused code, mostly the SHA384 and SHA512 implementations. */
 #if 0
 SECStatus
 SHA256_HashBuf(unsigned char *dest, const unsigned char *src,
                unsigned int src_length)
 {
     SHA256Context ctx;
     unsigned int outLen;
 
     SHA256_Begin(&ctx);
@@ skipping 28 matching lines @@
 
 SHA256Context *
 SHA256_Resurrect(unsigned char *space, void *arg)
 {
     SHA256Context *ctx = SHA256_NewContext();
     if (ctx)
         PORT_Memcpy(ctx, space, sizeof *ctx);
     return ctx;
 }
 
-void SHA256_Clone(SHA256Context *dest, SHA256Context *src)
-{
-    memcpy(dest, src, sizeof *dest);
-}
-
-
 /* ======= SHA512 and SHA384 common constants and defines ================= */
 
 /* common #defines for SHA512 and SHA384 */
 #if defined(HAVE_LONG_LONG)
 #define ROTR64(x,n) ((x >> n) | (x << (64 - n)))
 #define ROTL64(x,n) ((x << n) | (x >> (64 - n)))
 
 #define S0(x) (ROTR64(x,28) ^ ROTR64(x,34) ^ ROTR64(x,39))
 #define S1(x) (ROTR64(x,14) ^ ROTR64(x,18) ^ ROTR64(x,41))
 #define s0(x) (t1 = x, ROTR64(t1, 1) ^ ROTR64(t1, 8) ^ SHR(t1,7))
@@ skipping 844 matching lines @@
     } else {
         while (i-- > 0) {
             time512();
         }
         printf("done\n");
     }
     return 0;
 }
 
 #endif