1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/io/Base64.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,350 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "Base64.h"
1.10 +
1.11 +#include "nsIInputStream.h"
1.12 +#include "nsString.h"
1.13 +
1.14 +#include "plbase64.h"
1.15 +
1.16 +namespace {
1.17 +
1.18 +// BEGIN base64 encode code copied and modified from NSPR
1.19 +const unsigned char *base = (unsigned char *)"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
1.20 +
1.21 +template <typename T>
1.22 +static void
1.23 +Encode3to4(const unsigned char *src, T *dest)
1.24 +{
1.25 + uint32_t b32 = (uint32_t)0;
1.26 + int i, j = 18;
1.27 +
1.28 + for( i = 0; i < 3; i++ )
1.29 + {
1.30 + b32 <<= 8;
1.31 + b32 |= (uint32_t)src[i];
1.32 + }
1.33 +
1.34 + for( i = 0; i < 4; i++ )
1.35 + {
1.36 + dest[i] = base[ (uint32_t)((b32>>j) & 0x3F) ];
1.37 + j -= 6;
1.38 + }
1.39 +}
1.40 +
1.41 +template <typename T>
1.42 +static void
1.43 +Encode2to4(const unsigned char *src, T *dest)
1.44 +{
1.45 + dest[0] = base[ (uint32_t)((src[0]>>2) & 0x3F) ];
1.46 + dest[1] = base[ (uint32_t)(((src[0] & 0x03) << 4) | ((src[1] >> 4) & 0x0F)) ];
1.47 + dest[2] = base[ (uint32_t)((src[1] & 0x0F) << 2) ];
1.48 + dest[3] = (unsigned char)'=';
1.49 +}
1.50 +
1.51 +template <typename T>
1.52 +static void
1.53 +Encode1to4(const unsigned char *src, T *dest)
1.54 +{
1.55 + dest[0] = base[ (uint32_t)((src[0]>>2) & 0x3F) ];
1.56 + dest[1] = base[ (uint32_t)((src[0] & 0x03) << 4) ];
1.57 + dest[2] = (unsigned char)'=';
1.58 + dest[3] = (unsigned char)'=';
1.59 +}
1.60 +
1.61 +template <typename T>
1.62 +static void
1.63 +Encode(const unsigned char *src, uint32_t srclen, T *dest)
1.64 +{
1.65 + while( srclen >= 3 )
1.66 + {
1.67 + Encode3to4(src, dest);
1.68 + src += 3;
1.69 + dest += 4;
1.70 + srclen -= 3;
1.71 + }
1.72 +
1.73 + switch( srclen )
1.74 + {
1.75 + case 2:
1.76 + Encode2to4(src, dest);
1.77 + break;
1.78 + case 1:
1.79 + Encode1to4(src, dest);
1.80 + break;
1.81 + case 0:
1.82 + break;
1.83 + default:
1.84 + NS_NOTREACHED("coding error");
1.85 + }
1.86 +}
1.87 +
1.88 +// END base64 encode code copied and modified from NSPR.
1.89 +
1.90 +template <typename T>
1.91 +struct EncodeInputStream_State {
1.92 + unsigned char c[3];
1.93 + uint8_t charsOnStack;
1.94 + typename T::char_type* buffer;
1.95 +};
1.96 +
1.97 +template <typename T>
1.98 +NS_METHOD
1.99 +EncodeInputStream_Encoder(nsIInputStream *aStream,
1.100 + void *aClosure,
1.101 + const char *aFromSegment,
1.102 + uint32_t aToOffset,
1.103 + uint32_t aCount,
1.104 + uint32_t *aWriteCount)
1.105 +{
1.106 + NS_ASSERTION(aCount > 0, "Er, what?");
1.107 +
1.108 + EncodeInputStream_State<T>* state =
1.109 + static_cast<EncodeInputStream_State<T>*>(aClosure);
1.110 +
1.111 + // If we have any data left from last time, encode it now.
1.112 + uint32_t countRemaining = aCount;
1.113 + const unsigned char *src = (const unsigned char*)aFromSegment;
1.114 + if (state->charsOnStack) {
1.115 + unsigned char firstSet[4];
1.116 + if (state->charsOnStack == 1) {
1.117 + firstSet[0] = state->c[0];
1.118 + firstSet[1] = src[0];
1.119 + firstSet[2] = (countRemaining > 1) ? src[1] : '\0';
1.120 + firstSet[3] = '\0';
1.121 + } else /* state->charsOnStack == 2 */ {
1.122 + firstSet[0] = state->c[0];
1.123 + firstSet[1] = state->c[1];
1.124 + firstSet[2] = src[0];
1.125 + firstSet[3] = '\0';
1.126 + }
1.127 + Encode(firstSet, 3, state->buffer);
1.128 + state->buffer += 4;
1.129 + countRemaining -= (3 - state->charsOnStack);
1.130 + src += (3 - state->charsOnStack);
1.131 + state->charsOnStack = 0;
1.132 + }
1.133 +
1.134 + // Encode the bulk of the
1.135 + uint32_t encodeLength = countRemaining - countRemaining % 3;
1.136 + NS_ABORT_IF_FALSE(encodeLength % 3 == 0,
1.137 + "Should have an exact number of triplets!");
1.138 + Encode(src, encodeLength, state->buffer);
1.139 + state->buffer += (encodeLength / 3) * 4;
1.140 + src += encodeLength;
1.141 + countRemaining -= encodeLength;
1.142 +
1.143 + // We must consume all data, so if there's some data left stash it
1.144 + *aWriteCount = aCount;
1.145 +
1.146 + if (countRemaining) {
1.147 + // We should never have a full triplet left at this point.
1.148 + NS_ABORT_IF_FALSE(countRemaining < 3, "We should have encoded more!");
1.149 + state->c[0] = src[0];
1.150 + state->c[1] = (countRemaining == 2) ? src[1] : '\0';
1.151 + state->charsOnStack = countRemaining;
1.152 + }
1.153 +
1.154 + return NS_OK;
1.155 +}
1.156 +
1.157 +template <typename T>
1.158 +nsresult
1.159 +EncodeInputStream(nsIInputStream *aInputStream,
1.160 + T &aDest,
1.161 + uint32_t aCount,
1.162 + uint32_t aOffset)
1.163 +{
1.164 + nsresult rv;
1.165 + uint64_t count64 = aCount;
1.166 +
1.167 + if (!aCount) {
1.168 + rv = aInputStream->Available(&count64);
1.169 + if (NS_WARN_IF(NS_FAILED(rv)))
1.170 + return rv;
1.171 + // if count64 is over 4GB, it will be failed at the below condition,
1.172 + // then will return NS_ERROR_OUT_OF_MEMORY
1.173 + aCount = (uint32_t)count64;
1.174 + }
1.175 +
1.176 + uint64_t countlong =
1.177 + (count64 + 2) / 3 * 4; // +2 due to integer math.
1.178 + if (countlong + aOffset > UINT32_MAX)
1.179 + return NS_ERROR_OUT_OF_MEMORY;
1.180 +
1.181 + uint32_t count = uint32_t(countlong);
1.182 +
1.183 + aDest.SetLength(count + aOffset);
1.184 + if (aDest.Length() != count + aOffset)
1.185 + return NS_ERROR_OUT_OF_MEMORY;
1.186 +
1.187 + EncodeInputStream_State<T> state;
1.188 + state.charsOnStack = 0;
1.189 + state.c[2] = '\0';
1.190 + state.buffer = aOffset + aDest.BeginWriting();
1.191 +
1.192 + while (1) {
1.193 + uint32_t read = 0;
1.194 +
1.195 + rv = aInputStream->ReadSegments(&EncodeInputStream_Encoder<T>,
1.196 + (void*)&state,
1.197 + aCount,
1.198 + &read);
1.199 + if (NS_FAILED(rv)) {
1.200 + if (rv == NS_BASE_STREAM_WOULD_BLOCK)
1.201 + NS_RUNTIMEABORT("Not implemented for async streams!");
1.202 + if (rv == NS_ERROR_NOT_IMPLEMENTED)
1.203 + NS_RUNTIMEABORT("Requires a stream that implements ReadSegments!");
1.204 + return rv;
1.205 + }
1.206 +
1.207 + if (!read)
1.208 + break;
1.209 + }
1.210 +
1.211 + // Finish encoding if anything is left
1.212 + if (state.charsOnStack)
1.213 + Encode(state.c, state.charsOnStack, state.buffer);
1.214 +
1.215 + if (aDest.Length())
1.216 + // May belong to an nsCString with an unallocated buffer, so only null
1.217 + // terminate if there is a need to.
1.218 + *aDest.EndWriting() = '\0';
1.219 +
1.220 + return NS_OK;
1.221 +}
1.222 +
1.223 +} // namespace (anonymous)
1.224 +
1.225 +namespace mozilla {
1.226 +
1.227 +nsresult
1.228 +Base64EncodeInputStream(nsIInputStream *aInputStream,
1.229 + nsACString &aDest,
1.230 + uint32_t aCount,
1.231 + uint32_t aOffset)
1.232 +{
1.233 + return EncodeInputStream<nsACString>(aInputStream, aDest, aCount, aOffset);
1.234 +}
1.235 +
1.236 +nsresult
1.237 +Base64EncodeInputStream(nsIInputStream *aInputStream,
1.238 + nsAString &aDest,
1.239 + uint32_t aCount,
1.240 + uint32_t aOffset)
1.241 +{
1.242 + return EncodeInputStream<nsAString>(aInputStream, aDest, aCount, aOffset);
1.243 +}
1.244 +
1.245 +nsresult
1.246 +Base64Encode(const nsACString &aBinaryData, nsACString &aString)
1.247 +{
1.248 + // Check for overflow.
1.249 + if (aBinaryData.Length() > (UINT32_MAX / 4) * 3) {
1.250 + return NS_ERROR_FAILURE;
1.251 + }
1.252 +
1.253 + // Don't ask PR_Base64Encode to encode empty strings
1.254 + if (aBinaryData.IsEmpty()) {
1.255 + aString.Truncate();
1.256 + return NS_OK;
1.257 + }
1.258 +
1.259 + uint32_t stringLen = ((aBinaryData.Length() + 2) / 3) * 4;
1.260 +
1.261 + char *buffer;
1.262 +
1.263 + // Add one byte for null termination.
1.264 + if (aString.SetCapacity(stringLen + 1, fallible_t()) &&
1.265 + (buffer = aString.BeginWriting()) &&
1.266 + PL_Base64Encode(aBinaryData.BeginReading(), aBinaryData.Length(), buffer)) {
1.267 + // PL_Base64Encode doesn't null terminate the buffer for us when we pass
1.268 + // the buffer in. Do that manually.
1.269 + buffer[stringLen] = '\0';
1.270 +
1.271 + aString.SetLength(stringLen);
1.272 + return NS_OK;
1.273 + }
1.274 +
1.275 + aString.Truncate();
1.276 + return NS_ERROR_INVALID_ARG;
1.277 +}
1.278 +
1.279 +nsresult
1.280 +Base64Encode(const nsAString &aString, nsAString &aBinaryData)
1.281 +{
1.282 + NS_LossyConvertUTF16toASCII string(aString);
1.283 + nsAutoCString binaryData;
1.284 +
1.285 + nsresult rv = Base64Encode(string, binaryData);
1.286 + if (NS_SUCCEEDED(rv)) {
1.287 + CopyASCIItoUTF16(binaryData, aBinaryData);
1.288 + } else {
1.289 + aBinaryData.Truncate();
1.290 + }
1.291 +
1.292 + return rv;
1.293 +}
1.294 +
1.295 +nsresult
1.296 +Base64Decode(const nsACString &aString, nsACString &aBinaryData)
1.297 +{
1.298 + // Check for overflow.
1.299 + if (aString.Length() > UINT32_MAX / 3) {
1.300 + return NS_ERROR_FAILURE;
1.301 + }
1.302 +
1.303 + // Don't ask PR_Base64Decode to decode the empty string
1.304 + if (aString.IsEmpty()) {
1.305 + aBinaryData.Truncate();
1.306 + return NS_OK;
1.307 + }
1.308 +
1.309 + uint32_t binaryDataLen = ((aString.Length() * 3) / 4);
1.310 +
1.311 + char *buffer;
1.312 +
1.313 + // Add one byte for null termination.
1.314 + if (aBinaryData.SetCapacity(binaryDataLen + 1, fallible_t()) &&
1.315 + (buffer = aBinaryData.BeginWriting()) &&
1.316 + PL_Base64Decode(aString.BeginReading(), aString.Length(), buffer)) {
1.317 + // PL_Base64Decode doesn't null terminate the buffer for us when we pass
1.318 + // the buffer in. Do that manually, taking into account the number of '='
1.319 + // characters we were passed.
1.320 + if (!aString.IsEmpty() && aString[aString.Length() - 1] == '=') {
1.321 + if (aString.Length() > 1 && aString[aString.Length() - 2] == '=') {
1.322 + binaryDataLen -= 2;
1.323 + } else {
1.324 + binaryDataLen -= 1;
1.325 + }
1.326 + }
1.327 + buffer[binaryDataLen] = '\0';
1.328 +
1.329 + aBinaryData.SetLength(binaryDataLen);
1.330 + return NS_OK;
1.331 + }
1.332 +
1.333 + aBinaryData.Truncate();
1.334 + return NS_ERROR_INVALID_ARG;
1.335 +}
1.336 +
1.337 +nsresult
1.338 +Base64Decode(const nsAString &aBinaryData, nsAString &aString)
1.339 +{
1.340 + NS_LossyConvertUTF16toASCII binaryData(aBinaryData);
1.341 + nsAutoCString string;
1.342 +
1.343 + nsresult rv = Base64Decode(binaryData, string);
1.344 + if (NS_SUCCEEDED(rv)) {
1.345 + CopyASCIItoUTF16(string, aString);
1.346 + } else {
1.347 + aString.Truncate();
1.348 + }
1.349 +
1.350 + return rv;
1.351 +}
1.352 +
1.353 +} // namespace mozilla
