зеркало из https://github.com/mozilla/gecko-dev.git
762 строки
20 KiB
C++
762 строки
20 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#include "Base64.h"
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#include "mozilla/ArrayUtils.h"
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#include "mozilla/ScopeExit.h"
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#include "mozilla/UniquePtrExtensions.h"
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#include "nsIInputStream.h"
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#include "nsString.h"
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#include "nsTArray.h"
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#include "plbase64.h"
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namespace {
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// BEGIN base64 encode code copied and modified from NSPR
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const unsigned char* base =
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(unsigned char*)"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
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"abcdefghijklmnopqrstuvwxyz"
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"0123456789+/";
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// The Base64 encoder assumes all characters are less than 256; for 16-bit
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// strings, that means assuming that all characters are within range, and
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// masking off high bits if necessary.
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template<typename T>
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uint8_t
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CharTo8Bit(T aChar)
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{
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return uint8_t(aChar);
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}
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template<typename SrcT, typename DestT>
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static void
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Encode3to4(const SrcT* aSrc, DestT* aDest)
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{
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uint32_t b32 = (uint32_t)0;
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int i, j = 18;
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for (i = 0; i < 3; ++i) {
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b32 <<= 8;
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b32 |= CharTo8Bit(aSrc[i]);
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}
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for (i = 0; i < 4; ++i) {
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aDest[i] = base[(uint32_t)((b32 >> j) & 0x3F)];
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j -= 6;
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}
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}
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template<typename SrcT, typename DestT>
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static void
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Encode2to4(const SrcT* aSrc, DestT* aDest)
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{
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uint8_t src0 = CharTo8Bit(aSrc[0]);
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uint8_t src1 = CharTo8Bit(aSrc[1]);
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aDest[0] = base[(uint32_t)((src0 >> 2) & 0x3F)];
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aDest[1] = base[(uint32_t)(((src0 & 0x03) << 4) | ((src1 >> 4) & 0x0F))];
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aDest[2] = base[(uint32_t)((src1 & 0x0F) << 2)];
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aDest[3] = DestT('=');
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}
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template<typename SrcT, typename DestT>
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static void
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Encode1to4(const SrcT* aSrc, DestT* aDest)
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{
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uint8_t src0 = CharTo8Bit(aSrc[0]);
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aDest[0] = base[(uint32_t)((src0 >> 2) & 0x3F)];
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aDest[1] = base[(uint32_t)((src0 & 0x03) << 4)];
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aDest[2] = DestT('=');
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aDest[3] = DestT('=');
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}
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template<typename SrcT, typename DestT>
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static void
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Encode(const SrcT* aSrc, uint32_t aSrcLen, DestT* aDest)
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{
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while (aSrcLen >= 3) {
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Encode3to4(aSrc, aDest);
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aSrc += 3;
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aDest += 4;
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aSrcLen -= 3;
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}
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switch (aSrcLen) {
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case 2:
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Encode2to4(aSrc, aDest);
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break;
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case 1:
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Encode1to4(aSrc, aDest);
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break;
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case 0:
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break;
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default:
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NS_NOTREACHED("coding error");
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}
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}
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// END base64 encode code copied and modified from NSPR.
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template<typename T>
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struct EncodeInputStream_State
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{
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unsigned char c[3];
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uint8_t charsOnStack;
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typename T::char_type* buffer;
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};
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template<typename T>
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nsresult
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EncodeInputStream_Encoder(nsIInputStream* aStream,
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void* aClosure,
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const char* aFromSegment,
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uint32_t aToOffset,
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uint32_t aCount,
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uint32_t* aWriteCount)
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{
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NS_ASSERTION(aCount > 0, "Er, what?");
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EncodeInputStream_State<T>* state =
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static_cast<EncodeInputStream_State<T>*>(aClosure);
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// If we have any data left from last time, encode it now.
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uint32_t countRemaining = aCount;
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const unsigned char* src = (const unsigned char*)aFromSegment;
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if (state->charsOnStack) {
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unsigned char firstSet[4];
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if (state->charsOnStack == 1) {
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firstSet[0] = state->c[0];
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firstSet[1] = src[0];
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firstSet[2] = (countRemaining > 1) ? src[1] : '\0';
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firstSet[3] = '\0';
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} else /* state->charsOnStack == 2 */ {
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firstSet[0] = state->c[0];
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firstSet[1] = state->c[1];
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firstSet[2] = src[0];
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firstSet[3] = '\0';
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}
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Encode(firstSet, 3, state->buffer);
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state->buffer += 4;
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countRemaining -= (3 - state->charsOnStack);
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src += (3 - state->charsOnStack);
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state->charsOnStack = 0;
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}
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// Encode the bulk of the
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uint32_t encodeLength = countRemaining - countRemaining % 3;
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MOZ_ASSERT(encodeLength % 3 == 0,
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"Should have an exact number of triplets!");
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Encode(src, encodeLength, state->buffer);
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state->buffer += (encodeLength / 3) * 4;
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src += encodeLength;
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countRemaining -= encodeLength;
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// We must consume all data, so if there's some data left stash it
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*aWriteCount = aCount;
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if (countRemaining) {
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// We should never have a full triplet left at this point.
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MOZ_ASSERT(countRemaining < 3, "We should have encoded more!");
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state->c[0] = src[0];
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state->c[1] = (countRemaining == 2) ? src[1] : '\0';
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state->charsOnStack = countRemaining;
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}
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return NS_OK;
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}
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template<typename T>
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nsresult
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EncodeInputStream(nsIInputStream* aInputStream,
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T& aDest,
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uint32_t aCount,
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uint32_t aOffset)
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{
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nsresult rv;
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uint64_t count64 = aCount;
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if (!aCount) {
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rv = aInputStream->Available(&count64);
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if (NS_WARN_IF(NS_FAILED(rv))) {
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return rv;
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}
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// if count64 is over 4GB, it will be failed at the below condition,
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// then will return NS_ERROR_OUT_OF_MEMORY
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aCount = (uint32_t)count64;
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}
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uint64_t countlong =
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(count64 + 2) / 3 * 4; // +2 due to integer math.
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if (countlong + aOffset > UINT32_MAX) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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uint32_t count = uint32_t(countlong);
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if (!aDest.SetLength(count + aOffset, mozilla::fallible)) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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EncodeInputStream_State<T> state;
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state.charsOnStack = 0;
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state.c[2] = '\0';
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state.buffer = aOffset + aDest.BeginWriting();
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while (1) {
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uint32_t read = 0;
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rv = aInputStream->ReadSegments(&EncodeInputStream_Encoder<T>,
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(void*)&state,
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aCount,
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&read);
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if (NS_FAILED(rv)) {
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if (rv == NS_BASE_STREAM_WOULD_BLOCK) {
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MOZ_CRASH("Not implemented for async streams!");
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}
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if (rv == NS_ERROR_NOT_IMPLEMENTED) {
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MOZ_CRASH("Requires a stream that implements ReadSegments!");
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}
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return rv;
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}
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if (!read) {
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break;
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}
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}
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// Finish encoding if anything is left
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if (state.charsOnStack) {
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Encode(state.c, state.charsOnStack, state.buffer);
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}
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if (aDest.Length()) {
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// May belong to an nsCString with an unallocated buffer, so only null
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// terminate if there is a need to.
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*aDest.EndWriting() = '\0';
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}
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return NS_OK;
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}
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// Maps an encoded character to a value in the Base64 alphabet, per
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// RFC 4648, Table 1. Invalid input characters map to UINT8_MAX.
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static const uint8_t kBase64DecodeTable[] = {
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// clang-format off
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/* 0 */ 255, 255, 255, 255, 255, 255, 255, 255,
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/* 8 */ 255, 255, 255, 255, 255, 255, 255, 255,
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/* 16 */ 255, 255, 255, 255, 255, 255, 255, 255,
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/* 24 */ 255, 255, 255, 255, 255, 255, 255, 255,
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/* 32 */ 255, 255, 255, 255, 255, 255, 255, 255,
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/* 40 */ 255, 255, 255,
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62 /* + */,
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255, 255, 255,
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63 /* / */,
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/* 48 */ /* 0 - 9 */ 52, 53, 54, 55, 56, 57, 58, 59,
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/* 56 */ 60, 61, 255, 255, 255, 255, 255, 255,
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/* 64 */ 255, /* A - Z */ 0, 1, 2, 3, 4, 5, 6,
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/* 72 */ 7, 8, 9, 10, 11, 12, 13, 14,
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/* 80 */ 15, 16, 17, 18, 19, 20, 21, 22,
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/* 88 */ 23, 24, 25, 255, 255, 255, 255, 255,
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/* 96 */ 255, /* a - z */ 26, 27, 28, 29, 30, 31, 32,
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/* 104 */ 33, 34, 35, 36, 37, 38, 39, 40,
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/* 112 */ 41, 42, 43, 44, 45, 46, 47, 48,
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/* 120 */ 49, 50, 51, 255, 255, 255, 255, 255,
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};
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// clang-format on
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template<typename T>
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MOZ_MUST_USE bool
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Base64CharToValue(T aChar, uint8_t* aValue)
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{
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static const size_t mask = 0x7f;
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static_assert((mask + 1) == sizeof(kBase64DecodeTable)/sizeof(kBase64DecodeTable[0]),
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"wrong mask");
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size_t index = static_cast<uint8_t>(aChar);
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if (index & ~mask) {
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return false;
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}
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*aValue = kBase64DecodeTable[index & mask];
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return *aValue != 255;
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}
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static const char kBase64URLAlphabet[] =
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"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
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// Maps an encoded character to a value in the Base64 URL alphabet, per
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// RFC 4648, Table 2. Invalid input characters map to UINT8_MAX.
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static const uint8_t kBase64URLDecodeTable[] = {
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// clang-format off
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255, 255, 255, 255, 255, 255, 255, 255,
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255, 255, 255, 255, 255, 255, 255, 255,
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255, 255, 255, 255, 255, 255, 255, 255,
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255, 255, 255, 255, 255, 255, 255, 255,
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255, 255, 255, 255, 255, 255, 255, 255,
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255, 255, 255, 255, 255,
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62 /* - */,
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255, 255,
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52, 53, 54, 55, 56, 57, 58, 59, 60, 61, /* 0 - 9 */
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255, 255, 255, 255, 255, 255, 255,
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
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16, 17, 18, 19, 20, 21, 22, 23, 24, 25, /* A - Z */
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255, 255, 255, 255,
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63 /* _ */,
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255,
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26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
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42, 43, 44, 45, 46, 47, 48, 49, 50, 51, /* a - z */
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255, 255, 255, 255,
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};
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// clang-format on
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bool
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Base64URLCharToValue(char aChar, uint8_t* aValue) {
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uint8_t index = static_cast<uint8_t>(aChar);
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*aValue = kBase64URLDecodeTable[index & 0x7f];
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return (*aValue != 255) && !(index & ~0x7f);
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}
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} // namespace
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namespace mozilla {
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nsresult
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Base64EncodeInputStream(nsIInputStream* aInputStream,
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nsACString& aDest,
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uint32_t aCount,
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uint32_t aOffset)
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{
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return EncodeInputStream<nsACString>(aInputStream, aDest, aCount, aOffset);
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}
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nsresult
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Base64EncodeInputStream(nsIInputStream* aInputStream,
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nsAString& aDest,
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uint32_t aCount,
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uint32_t aOffset)
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{
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return EncodeInputStream<nsAString>(aInputStream, aDest, aCount, aOffset);
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}
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nsresult
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Base64Encode(const char* aBinary, uint32_t aBinaryLen, char** aBase64)
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{
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// Check for overflow.
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if (aBinaryLen > (UINT32_MAX / 4) * 3) {
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return NS_ERROR_FAILURE;
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}
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if (aBinaryLen == 0) {
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*aBase64 = (char*)moz_xmalloc(1);
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(*aBase64)[0] = '\0';
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return NS_OK;
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}
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*aBase64 = nullptr;
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uint32_t base64Len = ((aBinaryLen + 2) / 3) * 4;
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// Add one byte for null termination.
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UniqueFreePtr<char[]> base64((char*)malloc(base64Len + 1));
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if (!base64) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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Encode(aBinary, aBinaryLen, base64.get());
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base64[base64Len] = '\0';
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*aBase64 = base64.release();
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return NS_OK;
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}
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template<typename T>
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static nsresult
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Base64EncodeHelper(const T& aBinary, T& aBase64)
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{
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// Check for overflow.
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if (aBinary.Length() > (UINT32_MAX / 4) * 3) {
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return NS_ERROR_FAILURE;
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}
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if (aBinary.IsEmpty()) {
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aBase64.Truncate();
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return NS_OK;
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}
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uint32_t base64Len = ((aBinary.Length() + 2) / 3) * 4;
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// Add one byte for null termination.
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if (!aBase64.SetCapacity(base64Len + 1, fallible)) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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typename T::char_type* base64 = aBase64.BeginWriting();
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Encode(aBinary.BeginReading(), aBinary.Length(), base64);
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base64[base64Len] = '\0';
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aBase64.SetLength(base64Len);
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return NS_OK;
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}
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nsresult
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Base64Encode(const nsACString& aBinary, nsACString& aBase64)
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{
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return Base64EncodeHelper(aBinary, aBase64);
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}
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nsresult
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Base64Encode(const nsAString& aBinary, nsAString& aBase64)
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{
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return Base64EncodeHelper(aBinary, aBase64);
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}
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template<typename T, typename U, typename Decoder>
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static bool
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Decode4to3(const T* aSrc, U* aDest, Decoder aToVal)
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{
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uint8_t w, x, y, z;
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if (!aToVal(aSrc[0], &w) ||
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!aToVal(aSrc[1], &x) ||
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!aToVal(aSrc[2], &y) ||
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!aToVal(aSrc[3], &z)) {
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return false;
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}
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aDest[0] = U(uint8_t(w << 2 | x >> 4));
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aDest[1] = U(uint8_t(x << 4 | y >> 2));
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aDest[2] = U(uint8_t(y << 6 | z));
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return true;
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}
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template<typename T, typename U, typename Decoder>
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static bool
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Decode3to2(const T* aSrc, U* aDest, Decoder aToVal)
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{
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uint8_t w, x, y;
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if (!aToVal(aSrc[0], &w) ||
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!aToVal(aSrc[1], &x) ||
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!aToVal(aSrc[2], &y)) {
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return false;
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}
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aDest[0] = U(uint8_t(w << 2 | x >> 4));
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aDest[1] = U(uint8_t(x << 4 | y >> 2));
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return true;
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}
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template<typename T, typename U, typename Decoder>
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static bool
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Decode2to1(const T* aSrc, U* aDest, Decoder aToVal)
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{
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uint8_t w, x;
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if (!aToVal(aSrc[0], &w) ||
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!aToVal(aSrc[1], &x)) {
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return false;
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}
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aDest[0] = U(uint8_t(w << 2 | x >> 4));
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return true;
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}
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template<typename SrcT, typename DestT>
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static nsresult
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Base64DecodeHelper(const SrcT* aBase64, uint32_t aBase64Len, DestT* aBinary,
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uint32_t* aBinaryLen)
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{
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MOZ_ASSERT(aBinary);
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const SrcT* input = aBase64;
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uint32_t inputLength = aBase64Len;
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DestT* binary = aBinary;
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uint32_t binaryLength = 0;
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// Handle trailing '=' characters.
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if (inputLength && (inputLength % 4 == 0)) {
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if (aBase64[inputLength - 1] == SrcT('=')) {
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if (aBase64[inputLength - 2] == SrcT('=')) {
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inputLength -= 2;
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} else {
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inputLength -= 1;
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}
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}
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}
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while (inputLength >= 4) {
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if (!Decode4to3(input, binary, Base64CharToValue<SrcT>)) {
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return NS_ERROR_INVALID_ARG;
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}
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input += 4;
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inputLength -= 4;
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binary += 3;
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binaryLength += 3;
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}
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switch (inputLength) {
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case 3:
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if (!Decode3to2(input, binary, Base64CharToValue<SrcT>)) {
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return NS_ERROR_INVALID_ARG;
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}
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binaryLength += 2;
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break;
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case 2:
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if (!Decode2to1(input, binary, Base64CharToValue<SrcT>)) {
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
binaryLength += 1;
|
|
break;
|
|
case 1:
|
|
return NS_ERROR_INVALID_ARG;
|
|
case 0:
|
|
break;
|
|
default:
|
|
MOZ_CRASH("Too many characters leftover");
|
|
}
|
|
|
|
aBinary[binaryLength] = DestT('\0');
|
|
*aBinaryLen = binaryLength;
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
nsresult
|
|
Base64Decode(const char* aBase64, uint32_t aBase64Len, char** aBinary,
|
|
uint32_t* aBinaryLen)
|
|
{
|
|
// Check for overflow.
|
|
if (aBase64Len > UINT32_MAX / 3) {
|
|
return NS_ERROR_FAILURE;
|
|
}
|
|
|
|
// Don't ask PR_Base64Decode to decode the empty string.
|
|
if (aBase64Len == 0) {
|
|
*aBinary = (char*)moz_xmalloc(1);
|
|
(*aBinary)[0] = '\0';
|
|
*aBinaryLen = 0;
|
|
return NS_OK;
|
|
}
|
|
|
|
*aBinary = nullptr;
|
|
*aBinaryLen = (aBase64Len * 3) / 4;
|
|
|
|
// Add one byte for null termination.
|
|
UniqueFreePtr<char[]> binary((char*)malloc(*aBinaryLen + 1));
|
|
if (!binary) {
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
|
|
nsresult rv =
|
|
Base64DecodeHelper(aBase64, aBase64Len, binary.get(), aBinaryLen);
|
|
if (NS_FAILED(rv)) {
|
|
return rv;
|
|
}
|
|
|
|
*aBinary = binary.release();
|
|
return NS_OK;
|
|
}
|
|
|
|
template<typename T>
|
|
static nsresult
|
|
Base64DecodeString(const T& aBase64, T& aBinary)
|
|
{
|
|
// Check for overflow.
|
|
if (aBase64.Length() > UINT32_MAX / 3) {
|
|
return NS_ERROR_FAILURE;
|
|
}
|
|
|
|
// Don't decode the empty string
|
|
if (aBase64.IsEmpty()) {
|
|
aBinary.Truncate();
|
|
return NS_OK;
|
|
}
|
|
|
|
uint32_t binaryLen = ((aBase64.Length() * 3) / 4);
|
|
|
|
// Add one byte for null termination.
|
|
if (!aBinary.SetCapacity(binaryLen + 1, fallible)) {
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
|
|
typename T::char_type* binary = aBinary.BeginWriting();
|
|
nsresult rv = Base64DecodeHelper(aBase64.BeginReading(), aBase64.Length(),
|
|
binary, &binaryLen);
|
|
if (NS_FAILED(rv)) {
|
|
aBinary.Truncate();
|
|
return rv;
|
|
}
|
|
|
|
aBinary.SetLength(binaryLen);
|
|
return NS_OK;
|
|
}
|
|
|
|
nsresult
|
|
Base64Decode(const nsACString& aBase64, nsACString& aBinary)
|
|
{
|
|
return Base64DecodeString(aBase64, aBinary);
|
|
}
|
|
|
|
nsresult
|
|
Base64Decode(const nsAString& aBase64, nsAString& aBinary)
|
|
{
|
|
return Base64DecodeString(aBase64, aBinary);
|
|
}
|
|
|
|
nsresult
|
|
Base64URLDecode(const nsACString& aBase64,
|
|
Base64URLDecodePaddingPolicy aPaddingPolicy,
|
|
FallibleTArray<uint8_t>& aBinary)
|
|
{
|
|
// Don't decode empty strings.
|
|
if (aBase64.IsEmpty()) {
|
|
aBinary.Clear();
|
|
return NS_OK;
|
|
}
|
|
|
|
// Check for overflow.
|
|
uint32_t base64Len = aBase64.Length();
|
|
if (base64Len > UINT32_MAX / 3) {
|
|
return NS_ERROR_FAILURE;
|
|
}
|
|
const char* base64 = aBase64.BeginReading();
|
|
|
|
// The decoded length may be 1-2 bytes over, depending on the final quantum.
|
|
uint32_t binaryLen = (base64Len * 3) / 4;
|
|
|
|
// Determine whether to check for and ignore trailing padding.
|
|
bool maybePadded = false;
|
|
switch (aPaddingPolicy) {
|
|
case Base64URLDecodePaddingPolicy::Require:
|
|
if (base64Len % 4) {
|
|
// Padded input length must be a multiple of 4.
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
maybePadded = true;
|
|
break;
|
|
|
|
case Base64URLDecodePaddingPolicy::Ignore:
|
|
// Check for padding only if the length is a multiple of 4.
|
|
maybePadded = !(base64Len % 4);
|
|
break;
|
|
|
|
// If we're expecting unpadded input, no need for additional checks.
|
|
// `=` isn't in the decode table, so padded strings will fail to decode.
|
|
default:
|
|
MOZ_FALLTHROUGH_ASSERT("Invalid decode padding policy");
|
|
case Base64URLDecodePaddingPolicy::Reject:
|
|
break;
|
|
}
|
|
if (maybePadded && base64[base64Len - 1] == '=') {
|
|
if (base64[base64Len - 2] == '=') {
|
|
base64Len -= 2;
|
|
} else {
|
|
base64Len -= 1;
|
|
}
|
|
}
|
|
|
|
if (NS_WARN_IF(!aBinary.SetCapacity(binaryLen, mozilla::fallible))) {
|
|
return NS_ERROR_OUT_OF_MEMORY;
|
|
}
|
|
aBinary.SetLengthAndRetainStorage(binaryLen);
|
|
uint8_t* binary = aBinary.Elements();
|
|
|
|
for (; base64Len >= 4; base64Len -= 4) {
|
|
if (!Decode4to3(base64, binary, Base64URLCharToValue)) {
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
base64 += 4;
|
|
binary += 3;
|
|
}
|
|
|
|
if (base64Len == 3) {
|
|
if (!Decode3to2(base64, binary, Base64URLCharToValue)) {
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
binary += 2;
|
|
} else if (base64Len == 2) {
|
|
if (!Decode2to1(base64, binary, Base64URLCharToValue)) {
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
binary += 1;
|
|
} else if (base64Len) {
|
|
return NS_ERROR_INVALID_ARG;
|
|
}
|
|
|
|
// Set the length to the actual number of decoded bytes.
|
|
aBinary.TruncateLength(binary - aBinary.Elements());
|
|
return NS_OK;
|
|
}
|
|
|
|
nsresult
|
|
Base64URLEncode(uint32_t aBinaryLen, const uint8_t* aBinary,
|
|
Base64URLEncodePaddingPolicy aPaddingPolicy,
|
|
nsACString& aBase64)
|
|
{
|
|
// Don't encode empty strings.
|
|
if (aBinaryLen == 0) {
|
|
aBase64.Truncate();
|
|
return NS_OK;
|
|
}
|
|
|
|
// Check for overflow.
|
|
if (aBinaryLen > (UINT32_MAX / 4) * 3) {
|
|
return NS_ERROR_FAILURE;
|
|
}
|
|
|
|
// Allocate a buffer large enough to hold the encoded string with padding.
|
|
// Add one byte for null termination.
|
|
uint32_t base64Len = ((aBinaryLen + 2) / 3) * 4;
|
|
if (NS_WARN_IF(!aBase64.SetCapacity(base64Len + 1, fallible))) {
|
|
aBase64.Truncate();
|
|
return NS_ERROR_FAILURE;
|
|
}
|
|
|
|
char* base64 = aBase64.BeginWriting();
|
|
|
|
uint32_t index = 0;
|
|
for (; index + 3 <= aBinaryLen; index += 3) {
|
|
*base64++ = kBase64URLAlphabet[aBinary[index] >> 2];
|
|
*base64++ = kBase64URLAlphabet[((aBinary[index] & 0x3) << 4) |
|
|
(aBinary[index + 1] >> 4)];
|
|
*base64++ = kBase64URLAlphabet[((aBinary[index + 1] & 0xf) << 2) |
|
|
(aBinary[index + 2] >> 6)];
|
|
*base64++ = kBase64URLAlphabet[aBinary[index + 2] & 0x3f];
|
|
}
|
|
|
|
uint32_t remaining = aBinaryLen - index;
|
|
if (remaining == 1) {
|
|
*base64++ = kBase64URLAlphabet[aBinary[index] >> 2];
|
|
*base64++ = kBase64URLAlphabet[((aBinary[index] & 0x3) << 4)];
|
|
} else if (remaining == 2) {
|
|
*base64++ = kBase64URLAlphabet[aBinary[index] >> 2];
|
|
*base64++ = kBase64URLAlphabet[((aBinary[index] & 0x3) << 4) |
|
|
(aBinary[index + 1] >> 4)];
|
|
*base64++ = kBase64URLAlphabet[((aBinary[index + 1] & 0xf) << 2)];
|
|
}
|
|
|
|
uint32_t length = base64 - aBase64.BeginWriting();
|
|
if (aPaddingPolicy == Base64URLEncodePaddingPolicy::Include) {
|
|
if (length % 4 == 2) {
|
|
*base64++ = '=';
|
|
*base64++ = '=';
|
|
length += 2;
|
|
} else if (length % 4 == 3) {
|
|
*base64++ = '=';
|
|
length += 1;
|
|
}
|
|
} else {
|
|
MOZ_ASSERT(aPaddingPolicy == Base64URLEncodePaddingPolicy::Omit,
|
|
"Invalid encode padding policy");
|
|
}
|
|
|
|
// Null terminate and truncate to the actual number of characters.
|
|
*base64 = '\0';
|
|
aBase64.SetLength(length);
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
} // namespace mozilla
|