diff options
author | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
---|---|---|
committer | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
commit | 5f8de423f190bbb79a62f804151bc24824fa32d8 (patch) | |
tree | 10027f336435511475e392454359edea8e25895d /media/gmp-clearkey/0.1/ClearKeyUtils.cpp | |
parent | 49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff) | |
download | UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.lz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.xz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.zip |
Add m-esr52 at 52.6.0
Diffstat (limited to 'media/gmp-clearkey/0.1/ClearKeyUtils.cpp')
-rw-r--r-- | media/gmp-clearkey/0.1/ClearKeyUtils.cpp | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/media/gmp-clearkey/0.1/ClearKeyUtils.cpp b/media/gmp-clearkey/0.1/ClearKeyUtils.cpp new file mode 100644 index 000000000..b99a50a4d --- /dev/null +++ b/media/gmp-clearkey/0.1/ClearKeyUtils.cpp @@ -0,0 +1,541 @@ +/* + * Copyright 2015, Mozilla Foundation and contributors + * + * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <algorithm> +#include <ctype.h> +#include <stdarg.h> +#include <stdint.h> +#include <vector> + +#include "ClearKeyUtils.h" +#include "ClearKeyBase64.h" +#include "ArrayUtils.h" +#include <assert.h> +#include <memory.h> +#include "BigEndian.h" +#include "openaes/oaes_lib.h" + +using namespace std; + +void +CK_Log(const char* aFmt, ...) +{ + va_list ap; + + va_start(ap, aFmt); + vprintf(aFmt, ap); + va_end(ap); + + printf("\n"); + fflush(stdout); +} + +static void +IncrementIV(vector<uint8_t>& aIV) { + using mozilla::BigEndian; + + assert(aIV.size() == 16); + BigEndian::writeUint64(&aIV[8], BigEndian::readUint64(&aIV[8]) + 1); +} + +/* static */ void +ClearKeyUtils::DecryptAES(const vector<uint8_t>& aKey, + vector<uint8_t>& aData, vector<uint8_t>& aIV) +{ + assert(aIV.size() == CENC_KEY_LEN); + assert(aKey.size() == CENC_KEY_LEN); + + OAES_CTX* aes = oaes_alloc(); + oaes_key_import_data(aes, &aKey[0], aKey.size()); + oaes_set_option(aes, OAES_OPTION_ECB, nullptr); + + for (size_t i = 0; i < aData.size(); i += CENC_KEY_LEN) { + size_t encLen; + oaes_encrypt(aes, &aIV[0], CENC_KEY_LEN, nullptr, &encLen); + + vector<uint8_t> enc(encLen); + oaes_encrypt(aes, &aIV[0], CENC_KEY_LEN, &enc[0], &encLen); + + assert(encLen >= 2 * OAES_BLOCK_SIZE + CENC_KEY_LEN); + size_t blockLen = min(aData.size() - i, CENC_KEY_LEN); + for (size_t j = 0; j < blockLen; j++) { + aData[i + j] ^= enc[2 * OAES_BLOCK_SIZE + j]; + } + IncrementIV(aIV); + } + + oaes_free(&aes); +} + +/** + * ClearKey expects all Key IDs to be base64 encoded with non-standard alphabet + * and padding. + */ +static bool +EncodeBase64Web(vector<uint8_t> aBinary, string& aEncoded) +{ + const char sAlphabet[] = + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"; + const uint8_t sMask = 0x3f; + + aEncoded.resize((aBinary.size() * 8 + 5) / 6); + + // Pad binary data in case there's rubbish past the last byte. + aBinary.push_back(0); + + // Number of bytes not consumed in the previous character + uint32_t shift = 0; + + auto out = aEncoded.begin(); + auto data = aBinary.begin(); + for (string::size_type i = 0; i < aEncoded.length(); i++) { + if (shift) { + out[i] = (*data << (6 - shift)) & sMask; + data++; + } else { + out[i] = 0; + } + + out[i] += (*data >> (shift + 2)) & sMask; + shift = (shift + 2) % 8; + + // Cast idx to size_t before using it as an array-index, + // to pacify clang 'Wchar-subscripts' warning: + size_t idx = static_cast<size_t>(out[i]); + assert(idx < MOZ_ARRAY_LENGTH(sAlphabet)); // out of bounds index for 'sAlphabet' + out[i] = sAlphabet[idx]; + } + + return true; +} + +/* static */ void +ClearKeyUtils::MakeKeyRequest(const vector<KeyId>& aKeyIDs, + string& aOutRequest, + GMPSessionType aSessionType) +{ + assert(aKeyIDs.size() && aOutRequest.empty()); + + aOutRequest.append("{\"kids\":["); + for (size_t i = 0; i < aKeyIDs.size(); i++) { + if (i) { + aOutRequest.append(","); + } + aOutRequest.append("\""); + + string base64key; + EncodeBase64Web(aKeyIDs[i], base64key); + aOutRequest.append(base64key); + + aOutRequest.append("\""); + } + aOutRequest.append("],\"type\":"); + + aOutRequest.append("\""); + aOutRequest.append(SessionTypeToString(aSessionType)); + aOutRequest.append("\"}"); +} + +#define EXPECT_SYMBOL(CTX, X) do { \ + if (GetNextSymbol(CTX) != (X)) { \ + CK_LOGE("Unexpected symbol in JWK parser"); \ + return false; \ + } \ +} while (false) + +struct ParserContext { + const uint8_t* mIter; + const uint8_t* mEnd; +}; + +static uint8_t +PeekSymbol(ParserContext& aCtx) +{ + for (; aCtx.mIter < aCtx.mEnd; (aCtx.mIter)++) { + if (!isspace(*aCtx.mIter)) { + return *aCtx.mIter; + } + } + + return 0; +} + +static uint8_t +GetNextSymbol(ParserContext& aCtx) +{ + uint8_t sym = PeekSymbol(aCtx); + aCtx.mIter++; + return sym; +} + +static bool SkipToken(ParserContext& aCtx); + +static bool +SkipString(ParserContext& aCtx) +{ + EXPECT_SYMBOL(aCtx, '"'); + for (uint8_t sym = GetNextSymbol(aCtx); sym; sym = GetNextSymbol(aCtx)) { + if (sym == '\\') { + sym = GetNextSymbol(aCtx); + } else if (sym == '"') { + return true; + } + } + + return false; +} + +/** + * Skip whole object and values it contains. + */ +static bool +SkipObject(ParserContext& aCtx) +{ + EXPECT_SYMBOL(aCtx, '{'); + + if (PeekSymbol(aCtx) == '}') { + GetNextSymbol(aCtx); + return true; + } + + while (true) { + if (!SkipString(aCtx)) return false; + EXPECT_SYMBOL(aCtx, ':'); + if (!SkipToken(aCtx)) return false; + + if (PeekSymbol(aCtx) == '}') { + GetNextSymbol(aCtx); + return true; + } + EXPECT_SYMBOL(aCtx, ','); + } + + return false; +} + +/** + * Skip array value and the values it contains. + */ +static bool +SkipArray(ParserContext& aCtx) +{ + EXPECT_SYMBOL(aCtx, '['); + + if (PeekSymbol(aCtx) == ']') { + GetNextSymbol(aCtx); + return true; + } + + while (SkipToken(aCtx)) { + if (PeekSymbol(aCtx) == ']') { + GetNextSymbol(aCtx); + return true; + } + EXPECT_SYMBOL(aCtx, ','); + } + + return false; +} + +/** + * Skip unquoted literals like numbers, |true|, and |null|. + * (XXX and anything else that matches /([:alnum:]|[+-.])+/) + */ +static bool +SkipLiteral(ParserContext& aCtx) +{ + for (; aCtx.mIter < aCtx.mEnd; aCtx.mIter++) { + if (!isalnum(*aCtx.mIter) && + *aCtx.mIter != '.' && *aCtx.mIter != '-' && *aCtx.mIter != '+') { + return true; + } + } + + return false; +} + +static bool +SkipToken(ParserContext& aCtx) +{ + uint8_t startSym = PeekSymbol(aCtx); + if (startSym == '"') { + CK_LOGD("JWK parser skipping string"); + return SkipString(aCtx); + } else if (startSym == '{') { + CK_LOGD("JWK parser skipping object"); + return SkipObject(aCtx); + } else if (startSym == '[') { + CK_LOGD("JWK parser skipping array"); + return SkipArray(aCtx); + } else { + CK_LOGD("JWK parser skipping literal"); + return SkipLiteral(aCtx); + } + + return false; +} + +static bool +GetNextLabel(ParserContext& aCtx, string& aOutLabel) +{ + EXPECT_SYMBOL(aCtx, '"'); + + const uint8_t* start = aCtx.mIter; + for (uint8_t sym = GetNextSymbol(aCtx); sym; sym = GetNextSymbol(aCtx)) { + if (sym == '\\') { + GetNextSymbol(aCtx); + continue; + } + + if (sym == '"') { + aOutLabel.assign(start, aCtx.mIter - 1); + return true; + } + } + + return false; +} + +static bool +ParseKeyObject(ParserContext& aCtx, KeyIdPair& aOutKey) +{ + EXPECT_SYMBOL(aCtx, '{'); + + // Reject empty objects as invalid licenses. + if (PeekSymbol(aCtx) == '}') { + GetNextSymbol(aCtx); + return false; + } + + string keyId; + string key; + + while (true) { + string label; + string value; + + if (!GetNextLabel(aCtx, label)) { + return false; + } + + EXPECT_SYMBOL(aCtx, ':'); + if (label == "kty") { + if (!GetNextLabel(aCtx, value)) return false; + // By spec, type must be "oct". + if (value != "oct") return false; + } else if (label == "k" && PeekSymbol(aCtx) == '"') { + // if this isn't a string we will fall through to the SkipToken() path. + if (!GetNextLabel(aCtx, key)) return false; + } else if (label == "kid" && PeekSymbol(aCtx) == '"') { + if (!GetNextLabel(aCtx, keyId)) return false; + } else { + if (!SkipToken(aCtx)) return false; + } + + uint8_t sym = PeekSymbol(aCtx); + if (!sym || sym == '}') { + break; + } + EXPECT_SYMBOL(aCtx, ','); + } + + return !key.empty() && + !keyId.empty() && + DecodeBase64(keyId, aOutKey.mKeyId) && + DecodeBase64(key, aOutKey.mKey) && + GetNextSymbol(aCtx) == '}'; +} + +static bool +ParseKeys(ParserContext& aCtx, vector<KeyIdPair>& aOutKeys) +{ + // Consume start of array. + EXPECT_SYMBOL(aCtx, '['); + + while (true) { + KeyIdPair key; + if (!ParseKeyObject(aCtx, key)) { + CK_LOGE("Failed to parse key object"); + return false; + } + + assert(!key.mKey.empty() && !key.mKeyId.empty()); + aOutKeys.push_back(key); + + uint8_t sym = PeekSymbol(aCtx); + if (!sym || sym == ']') { + break; + } + + EXPECT_SYMBOL(aCtx, ','); + } + + return GetNextSymbol(aCtx) == ']'; +} + +/* static */ bool +ClearKeyUtils::ParseJWK(const uint8_t* aKeyData, uint32_t aKeyDataSize, + vector<KeyIdPair>& aOutKeys, + GMPSessionType aSessionType) +{ + ParserContext ctx; + ctx.mIter = aKeyData; + ctx.mEnd = aKeyData + aKeyDataSize; + + // Consume '{' from start of object. + EXPECT_SYMBOL(ctx, '{'); + + while (true) { + string label; + // Consume member key. + if (!GetNextLabel(ctx, label)) return false; + EXPECT_SYMBOL(ctx, ':'); + + if (label == "keys") { + // Parse "keys" array. + if (!ParseKeys(ctx, aOutKeys)) return false; + } else if (label == "type") { + // Consume type string. + string type; + if (!GetNextLabel(ctx, type)) return false; + if (type != SessionTypeToString(aSessionType)) { + return false; + } + } else { + SkipToken(ctx); + } + + // Check for end of object. + if (PeekSymbol(ctx) == '}') { + break; + } + + // Consume ',' between object members. + EXPECT_SYMBOL(ctx, ','); + } + + // Consume '}' from end of object. + EXPECT_SYMBOL(ctx, '}'); + + return true; +} + +static bool +ParseKeyIds(ParserContext& aCtx, vector<KeyId>& aOutKeyIds) +{ + // Consume start of array. + EXPECT_SYMBOL(aCtx, '['); + + while (true) { + string label; + vector<uint8_t> keyId; + if (!GetNextLabel(aCtx, label) || !DecodeBase64(label, keyId)) { + return false; + } + if (!keyId.empty() && keyId.size() <= kMaxKeyIdsLength) { + aOutKeyIds.push_back(keyId); + } + + uint8_t sym = PeekSymbol(aCtx); + if (!sym || sym == ']') { + break; + } + + EXPECT_SYMBOL(aCtx, ','); + } + + return GetNextSymbol(aCtx) == ']'; +} + + +/* static */ bool +ClearKeyUtils::ParseKeyIdsInitData(const uint8_t* aInitData, + uint32_t aInitDataSize, + vector<KeyId>& aOutKeyIds) +{ + ParserContext ctx; + ctx.mIter = aInitData; + ctx.mEnd = aInitData + aInitDataSize; + + // Consume '{' from start of object. + EXPECT_SYMBOL(ctx, '{'); + + while (true) { + string label; + // Consume member kids. + if (!GetNextLabel(ctx, label)) return false; + EXPECT_SYMBOL(ctx, ':'); + + if (label == "kids") { + // Parse "kids" array. + if (!ParseKeyIds(ctx, aOutKeyIds) || + aOutKeyIds.empty()) { + return false; + } + } else { + SkipToken(ctx); + } + + // Check for end of object. + if (PeekSymbol(ctx) == '}') { + break; + } + + // Consume ',' between object members. + EXPECT_SYMBOL(ctx, ','); + } + + // Consume '}' from end of object. + EXPECT_SYMBOL(ctx, '}'); + + return true; +} + +/* static */ const char* +ClearKeyUtils::SessionTypeToString(GMPSessionType aSessionType) +{ + switch (aSessionType) { + case kGMPTemporySession: return "temporary"; + case kGMPPersistentSession: return "persistent-license"; + default: { + assert(false); // Should not reach here. + return "invalid"; + } + } +} + +/* static */ bool +ClearKeyUtils::IsValidSessionId(const char* aBuff, uint32_t aLength) +{ + if (aLength > 10) { + // 10 is the max number of characters in UINT32_MAX when + // represented as a string; ClearKey session ids are integers. + return false; + } + for (uint32_t i = 0; i < aLength; i++) { + if (!isdigit(aBuff[i])) { + return false; + } + } + return true; +} + +GMPMutex* GMPCreateMutex() { + GMPMutex* mutex; + auto err = GetPlatform()->createmutex(&mutex); + assert(mutex); + return GMP_FAILED(err) ? nullptr : mutex; +} |