summaryrefslogtreecommitdiffstats
path: root/netwerk/cache2/CacheHashUtils.cpp
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--netwerk/cache2/CacheHashUtils.cpp226
1 files changed, 226 insertions, 0 deletions
diff --git a/netwerk/cache2/CacheHashUtils.cpp b/netwerk/cache2/CacheHashUtils.cpp
new file mode 100644
index 0000000000..6ac8205931
--- /dev/null
+++ b/netwerk/cache2/CacheHashUtils.cpp
@@ -0,0 +1,226 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "CacheHashUtils.h"
+
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/EndianUtils.h"
+#include "mozilla/SHA1.h"
+
+namespace mozilla::net {
+
+/**
+ * CacheHash::Hash(const char * key, uint32_t initval)
+ *
+ * See http://burtleburtle.net/bob/hash/evahash.html for more information
+ * about this hash function.
+ *
+ * This algorithm is used to check the data integrity.
+ */
+
+static inline void hashmix(uint32_t& a, uint32_t& b, uint32_t& c) {
+ a -= b;
+ a -= c;
+ a ^= (c >> 13);
+ b -= c;
+ b -= a;
+ b ^= (a << 8);
+ c -= a;
+ c -= b;
+ c ^= (b >> 13);
+ a -= b;
+ a -= c;
+ a ^= (c >> 12);
+ b -= c;
+ b -= a;
+ b ^= (a << 16);
+ c -= a;
+ c -= b;
+ c ^= (b >> 5);
+ a -= b;
+ a -= c;
+ a ^= (c >> 3);
+ b -= c;
+ b -= a;
+ b ^= (a << 10);
+ c -= a;
+ c -= b;
+ c ^= (b >> 15);
+}
+
+CacheHash::Hash32_t CacheHash::Hash(const char* aData, uint32_t aSize,
+ uint32_t aInitval) {
+ const uint8_t* k = reinterpret_cast<const uint8_t*>(aData);
+ uint32_t a, b, c, len;
+
+ /* Set up the internal state */
+ len = aSize;
+ a = b = 0x9e3779b9; /* the golden ratio; an arbitrary value */
+ c = aInitval; /* variable initialization of internal state */
+
+ /*---------------------------------------- handle most of the key */
+ while (len >= 12) {
+ a += k[0] + (uint32_t(k[1]) << 8) + (uint32_t(k[2]) << 16) +
+ (uint32_t(k[3]) << 24);
+ b += k[4] + (uint32_t(k[5]) << 8) + (uint32_t(k[6]) << 16) +
+ (uint32_t(k[7]) << 24);
+ c += k[8] + (uint32_t(k[9]) << 8) + (uint32_t(k[10]) << 16) +
+ (uint32_t(k[11]) << 24);
+ hashmix(a, b, c);
+ k += 12;
+ len -= 12;
+ }
+
+ /*------------------------------------- handle the last 11 bytes */
+ c += aSize;
+ switch (len) { /* all the case statements fall through */
+ case 11:
+ c += (uint32_t(k[10]) << 24);
+ [[fallthrough]];
+ case 10:
+ c += (uint32_t(k[9]) << 16);
+ [[fallthrough]];
+ case 9:
+ c += (uint32_t(k[8]) << 8);
+ [[fallthrough]];
+ /* the low-order byte of c is reserved for the length */
+ case 8:
+ b += (uint32_t(k[7]) << 24);
+ [[fallthrough]];
+ case 7:
+ b += (uint32_t(k[6]) << 16);
+ [[fallthrough]];
+ case 6:
+ b += (uint32_t(k[5]) << 8);
+ [[fallthrough]];
+ case 5:
+ b += k[4];
+ [[fallthrough]];
+ case 4:
+ a += (uint32_t(k[3]) << 24);
+ [[fallthrough]];
+ case 3:
+ a += (uint32_t(k[2]) << 16);
+ [[fallthrough]];
+ case 2:
+ a += (uint32_t(k[1]) << 8);
+ [[fallthrough]];
+ case 1:
+ a += k[0];
+ /* case 0: nothing left to add */
+ }
+ hashmix(a, b, c);
+
+ return c;
+}
+
+CacheHash::Hash16_t CacheHash::Hash16(const char* aData, uint32_t aSize,
+ uint32_t aInitval) {
+ Hash32_t hash = Hash(aData, aSize, aInitval);
+ return (hash & 0xFFFF);
+}
+
+NS_IMPL_ISUPPORTS0(CacheHash)
+
+CacheHash::CacheHash(uint32_t aInitval) : mC(aInitval) {}
+
+void CacheHash::Feed(uint32_t aVal, uint8_t aLen) {
+ switch (mPos) {
+ case 0:
+ mA += aVal;
+ mPos++;
+ break;
+
+ case 1:
+ mB += aVal;
+ mPos++;
+ break;
+
+ case 2:
+ mPos = 0;
+ if (aLen == 4) {
+ mC += aVal;
+ hashmix(mA, mB, mC);
+ } else {
+ mC += aVal << 8;
+ }
+ }
+
+ mLength += aLen;
+}
+
+void CacheHash::Update(const char* aData, uint32_t aLen) {
+ const uint8_t* data = reinterpret_cast<const uint8_t*>(aData);
+
+ MOZ_ASSERT(!mFinalized);
+
+ if (mBufPos) {
+ while (mBufPos != 4 && aLen) {
+ mBuf += uint32_t(*data) << 8 * mBufPos;
+ data++;
+ mBufPos++;
+ aLen--;
+ }
+
+ if (mBufPos == 4) {
+ mBufPos = 0;
+ Feed(mBuf);
+ mBuf = 0;
+ }
+ }
+
+ if (!aLen) return;
+
+ while (aLen >= 4) {
+ Feed(data[0] + (uint32_t(data[1]) << 8) + (uint32_t(data[2]) << 16) +
+ (uint32_t(data[3]) << 24));
+ data += 4;
+ aLen -= 4;
+ }
+
+ switch (aLen) {
+ case 3:
+ mBuf += data[2] << 16;
+ [[fallthrough]];
+ case 2:
+ mBuf += data[1] << 8;
+ [[fallthrough]];
+ case 1:
+ mBuf += data[0];
+ }
+
+ mBufPos = aLen;
+}
+
+CacheHash::Hash32_t CacheHash::GetHash() {
+ if (!mFinalized) {
+ if (mBufPos) {
+ Feed(mBuf, mBufPos);
+ }
+ mC += mLength;
+ hashmix(mA, mB, mC);
+ mFinalized = true;
+ }
+
+ return mC;
+}
+
+CacheHash::Hash16_t CacheHash::GetHash16() {
+ Hash32_t hash = GetHash();
+ return (hash & 0xFFFF);
+}
+
+OriginAttrsHash GetOriginAttrsHash(const mozilla::OriginAttributes& aOA) {
+ nsAutoCString suffix;
+ aOA.CreateSuffix(suffix);
+
+ SHA1Sum sum;
+ SHA1Sum::Hash hash;
+ sum.update(suffix.BeginReading(), suffix.Length());
+ sum.finish(hash);
+
+ return BigEndian::readUint64(&hash);
+}
+
+} // namespace mozilla::net