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-rw-r--r--xpcom/io/Base64.cpp645
1 files changed, 645 insertions, 0 deletions
diff --git a/xpcom/io/Base64.cpp b/xpcom/io/Base64.cpp
new file mode 100644
index 000000000..911c0595a
--- /dev/null
+++ b/xpcom/io/Base64.cpp
@@ -0,0 +1,645 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "Base64.h"
+
+#include "mozilla/UniquePtrExtensions.h"
+#include "nsIInputStream.h"
+#include "nsString.h"
+#include "nsTArray.h"
+
+#include "plbase64.h"
+
+namespace {
+
+// BEGIN base64 encode code copied and modified from NSPR
+const unsigned char* base =
+ (unsigned char*)"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/";
+
+template<typename T>
+static void
+Encode3to4(const unsigned char* aSrc, T* aDest)
+{
+ uint32_t b32 = (uint32_t)0;
+ int i, j = 18;
+
+ for (i = 0; i < 3; ++i) {
+ b32 <<= 8;
+ b32 |= (uint32_t)aSrc[i];
+ }
+
+ for (i = 0; i < 4; ++i) {
+ aDest[i] = base[(uint32_t)((b32 >> j) & 0x3F)];
+ j -= 6;
+ }
+}
+
+template<typename T>
+static void
+Encode2to4(const unsigned char* aSrc, T* aDest)
+{
+ aDest[0] = base[(uint32_t)((aSrc[0] >> 2) & 0x3F)];
+ aDest[1] = base[(uint32_t)(((aSrc[0] & 0x03) << 4) | ((aSrc[1] >> 4) & 0x0F))];
+ aDest[2] = base[(uint32_t)((aSrc[1] & 0x0F) << 2)];
+ aDest[3] = (unsigned char)'=';
+}
+
+template<typename T>
+static void
+Encode1to4(const unsigned char* aSrc, T* aDest)
+{
+ aDest[0] = base[(uint32_t)((aSrc[0] >> 2) & 0x3F)];
+ aDest[1] = base[(uint32_t)((aSrc[0] & 0x03) << 4)];
+ aDest[2] = (unsigned char)'=';
+ aDest[3] = (unsigned char)'=';
+}
+
+template<typename T>
+static void
+Encode(const unsigned char* aSrc, uint32_t aSrcLen, T* aDest)
+{
+ while (aSrcLen >= 3) {
+ Encode3to4(aSrc, aDest);
+ aSrc += 3;
+ aDest += 4;
+ aSrcLen -= 3;
+ }
+
+ switch (aSrcLen) {
+ case 2:
+ Encode2to4(aSrc, aDest);
+ break;
+ case 1:
+ Encode1to4(aSrc, aDest);
+ break;
+ case 0:
+ break;
+ default:
+ NS_NOTREACHED("coding error");
+ }
+}
+
+// END base64 encode code copied and modified from NSPR.
+
+template<typename T>
+struct EncodeInputStream_State
+{
+ unsigned char c[3];
+ uint8_t charsOnStack;
+ typename T::char_type* buffer;
+};
+
+template<typename T>
+nsresult
+EncodeInputStream_Encoder(nsIInputStream* aStream,
+ void* aClosure,
+ const char* aFromSegment,
+ uint32_t aToOffset,
+ uint32_t aCount,
+ uint32_t* aWriteCount)
+{
+ NS_ASSERTION(aCount > 0, "Er, what?");
+
+ EncodeInputStream_State<T>* state =
+ static_cast<EncodeInputStream_State<T>*>(aClosure);
+
+ // If we have any data left from last time, encode it now.
+ uint32_t countRemaining = aCount;
+ const unsigned char* src = (const unsigned char*)aFromSegment;
+ if (state->charsOnStack) {
+ unsigned char firstSet[4];
+ if (state->charsOnStack == 1) {
+ firstSet[0] = state->c[0];
+ firstSet[1] = src[0];
+ firstSet[2] = (countRemaining > 1) ? src[1] : '\0';
+ firstSet[3] = '\0';
+ } else /* state->charsOnStack == 2 */ {
+ firstSet[0] = state->c[0];
+ firstSet[1] = state->c[1];
+ firstSet[2] = src[0];
+ firstSet[3] = '\0';
+ }
+ Encode(firstSet, 3, state->buffer);
+ state->buffer += 4;
+ countRemaining -= (3 - state->charsOnStack);
+ src += (3 - state->charsOnStack);
+ state->charsOnStack = 0;
+ }
+
+ // Encode the bulk of the
+ uint32_t encodeLength = countRemaining - countRemaining % 3;
+ MOZ_ASSERT(encodeLength % 3 == 0,
+ "Should have an exact number of triplets!");
+ Encode(src, encodeLength, state->buffer);
+ state->buffer += (encodeLength / 3) * 4;
+ src += encodeLength;
+ countRemaining -= encodeLength;
+
+ // We must consume all data, so if there's some data left stash it
+ *aWriteCount = aCount;
+
+ if (countRemaining) {
+ // We should never have a full triplet left at this point.
+ MOZ_ASSERT(countRemaining < 3, "We should have encoded more!");
+ state->c[0] = src[0];
+ state->c[1] = (countRemaining == 2) ? src[1] : '\0';
+ state->charsOnStack = countRemaining;
+ }
+
+ return NS_OK;
+}
+
+template<typename T>
+nsresult
+EncodeInputStream(nsIInputStream* aInputStream,
+ T& aDest,
+ uint32_t aCount,
+ uint32_t aOffset)
+{
+ nsresult rv;
+ uint64_t count64 = aCount;
+
+ if (!aCount) {
+ rv = aInputStream->Available(&count64);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ // if count64 is over 4GB, it will be failed at the below condition,
+ // then will return NS_ERROR_OUT_OF_MEMORY
+ aCount = (uint32_t)count64;
+ }
+
+ uint64_t countlong =
+ (count64 + 2) / 3 * 4; // +2 due to integer math.
+ if (countlong + aOffset > UINT32_MAX) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ uint32_t count = uint32_t(countlong);
+
+ if (!aDest.SetLength(count + aOffset, mozilla::fallible)) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ EncodeInputStream_State<T> state;
+ state.charsOnStack = 0;
+ state.c[2] = '\0';
+ state.buffer = aOffset + aDest.BeginWriting();
+
+ while (1) {
+ uint32_t read = 0;
+
+ rv = aInputStream->ReadSegments(&EncodeInputStream_Encoder<T>,
+ (void*)&state,
+ aCount,
+ &read);
+ if (NS_FAILED(rv)) {
+ if (rv == NS_BASE_STREAM_WOULD_BLOCK) {
+ NS_RUNTIMEABORT("Not implemented for async streams!");
+ }
+ if (rv == NS_ERROR_NOT_IMPLEMENTED) {
+ NS_RUNTIMEABORT("Requires a stream that implements ReadSegments!");
+ }
+ return rv;
+ }
+
+ if (!read) {
+ break;
+ }
+ }
+
+ // Finish encoding if anything is left
+ if (state.charsOnStack) {
+ Encode(state.c, state.charsOnStack, state.buffer);
+ }
+
+ if (aDest.Length()) {
+ // May belong to an nsCString with an unallocated buffer, so only null
+ // terminate if there is a need to.
+ *aDest.EndWriting() = '\0';
+ }
+
+ return NS_OK;
+}
+
+static const char kBase64URLAlphabet[] =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
+
+// Maps an encoded character to a value in the Base64 URL alphabet, per
+// RFC 4648, Table 2. Invalid input characters map to UINT8_MAX.
+static const uint8_t kBase64URLDecodeTable[] = {
+ 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255, 255, 255, 255,
+ 255, 255, 255, 255, 255,
+ 62 /* - */,
+ 255, 255,
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, /* 0 - 9 */
+ 255, 255, 255, 255, 255, 255, 255,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, /* A - Z */
+ 255, 255, 255, 255,
+ 63 /* _ */,
+ 255,
+ 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
+ 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, /* a - z */
+ 255, 255, 255, 255,
+};
+
+bool
+Base64URLCharToValue(char aChar, uint8_t* aValue) {
+ uint8_t index = static_cast<uint8_t>(aChar);
+ *aValue = kBase64URLDecodeTable[index & 0x7f];
+ return (*aValue != 255) && !(index & ~0x7f);
+}
+
+} // namespace
+
+namespace mozilla {
+
+nsresult
+Base64EncodeInputStream(nsIInputStream* aInputStream,
+ nsACString& aDest,
+ uint32_t aCount,
+ uint32_t aOffset)
+{
+ return EncodeInputStream<nsACString>(aInputStream, aDest, aCount, aOffset);
+}
+
+nsresult
+Base64EncodeInputStream(nsIInputStream* aInputStream,
+ nsAString& aDest,
+ uint32_t aCount,
+ uint32_t aOffset)
+{
+ return EncodeInputStream<nsAString>(aInputStream, aDest, aCount, aOffset);
+}
+
+nsresult
+Base64Encode(const char* aBinary, uint32_t aBinaryLen, char** aBase64)
+{
+ // Check for overflow.
+ if (aBinaryLen > (UINT32_MAX / 4) * 3) {
+ return NS_ERROR_FAILURE;
+ }
+
+ // Don't ask PR_Base64Encode to encode empty strings.
+ if (aBinaryLen == 0) {
+ *aBase64 = (char*)moz_xmalloc(1);
+ (*aBase64)[0] = '\0';
+ return NS_OK;
+ }
+
+ *aBase64 = nullptr;
+ uint32_t base64Len = ((aBinaryLen + 2) / 3) * 4;
+
+ // Add one byte for null termination.
+ UniqueFreePtr<char[]> base64((char*)malloc(base64Len + 1));
+ if (!base64) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ if (!PL_Base64Encode(aBinary, aBinaryLen, base64.get())) {
+ return NS_ERROR_INVALID_ARG;
+ }
+
+ // PL_Base64Encode doesn't null terminate the buffer for us when we pass
+ // the buffer in. Do that manually.
+ base64[base64Len] = '\0';
+
+ *aBase64 = base64.release();
+ return NS_OK;
+}
+
+nsresult
+Base64Encode(const nsACString& aBinary, nsACString& aBase64)
+{
+ // Check for overflow.
+ if (aBinary.Length() > (UINT32_MAX / 4) * 3) {
+ return NS_ERROR_FAILURE;
+ }
+
+ // Don't ask PR_Base64Encode to encode empty strings.
+ if (aBinary.IsEmpty()) {
+ aBase64.Truncate();
+ return NS_OK;
+ }
+
+ uint32_t base64Len = ((aBinary.Length() + 2) / 3) * 4;
+
+ // Add one byte for null termination.
+ if (!aBase64.SetCapacity(base64Len + 1, fallible)) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ char* base64 = aBase64.BeginWriting();
+ if (!PL_Base64Encode(aBinary.BeginReading(), aBinary.Length(), base64)) {
+ aBase64.Truncate();
+ return NS_ERROR_INVALID_ARG;
+ }
+
+ // PL_Base64Encode doesn't null terminate the buffer for us when we pass
+ // the buffer in. Do that manually.
+ base64[base64Len] = '\0';
+
+ aBase64.SetLength(base64Len);
+ return NS_OK;
+}
+
+nsresult
+Base64Encode(const nsAString& aBinary, nsAString& aBase64)
+{
+ NS_LossyConvertUTF16toASCII binary(aBinary);
+ nsAutoCString base64;
+
+ nsresult rv = Base64Encode(binary, base64);
+ if (NS_SUCCEEDED(rv)) {
+ CopyASCIItoUTF16(base64, aBase64);
+ } else {
+ aBase64.Truncate();
+ }
+
+ return rv;
+}
+
+static nsresult
+Base64DecodeHelper(const char* aBase64, uint32_t aBase64Len, char* aBinary,
+ uint32_t* aBinaryLen)
+{
+ MOZ_ASSERT(aBinary);
+ if (!PL_Base64Decode(aBase64, aBase64Len, aBinary)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+
+ // PL_Base64Decode doesn't null terminate the buffer for us when we pass
+ // the buffer in. Do that manually, taking into account the number of '='
+ // characters we were passed.
+ if (aBase64Len != 0 && aBase64[aBase64Len - 1] == '=') {
+ if (aBase64Len > 1 && aBase64[aBase64Len - 2] == '=') {
+ *aBinaryLen -= 2;
+ } else {
+ *aBinaryLen -= 1;
+ }
+ }
+ aBinary[*aBinaryLen] = '\0';
+ 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;
+}
+
+nsresult
+Base64Decode(const nsACString& aBase64, nsACString& aBinary)
+{
+ // Check for overflow.
+ if (aBase64.Length() > UINT32_MAX / 3) {
+ return NS_ERROR_FAILURE;
+ }
+
+ // Don't ask PR_Base64Decode to 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;
+ }
+
+ char* 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 nsAString& aBase64, nsAString& aBinary)
+{
+ NS_LossyConvertUTF16toASCII base64(aBase64);
+ nsAutoCString binary;
+
+ nsresult rv = Base64Decode(base64, binary);
+ if (NS_SUCCEEDED(rv)) {
+ CopyASCIItoUTF16(binary, aBinary);
+ } else {
+ aBinary.Truncate();
+ }
+
+ return rv;
+}
+
+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) {
+ uint8_t w, x, y, z;
+ if (!Base64URLCharToValue(*base64++, &w) ||
+ !Base64URLCharToValue(*base64++, &x) ||
+ !Base64URLCharToValue(*base64++, &y) ||
+ !Base64URLCharToValue(*base64++, &z)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+ *binary++ = w << 2 | x >> 4;
+ *binary++ = x << 4 | y >> 2;
+ *binary++ = y << 6 | z;
+ }
+
+ if (base64Len == 3) {
+ uint8_t w, x, y;
+ if (!Base64URLCharToValue(*base64++, &w) ||
+ !Base64URLCharToValue(*base64++, &x) ||
+ !Base64URLCharToValue(*base64++, &y)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+ *binary++ = w << 2 | x >> 4;
+ *binary++ = x << 4 | y >> 2;
+ } else if (base64Len == 2) {
+ uint8_t w, x;
+ if (!Base64URLCharToValue(*base64++, &w) ||
+ !Base64URLCharToValue(*base64++, &x)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+ *binary++ = w << 2 | x >> 4;
+ } 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