dom/crypto/CryptoBuffer.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "CryptoBuffer.h"
   8 #include "secitem.h"
   9 #include "mozilla/Base64.h"
  10 #include "mozilla/dom/UnionTypes.h"
  11
  12 namespace mozilla::dom {
  13
  14 uint8_t* CryptoBuffer::Assign(const CryptoBuffer& aData) {
  15   // Same as in nsTArray_Impl::operator=, but return the value
  16   // returned from ReplaceElementsAt to enable OOM detection
  17   return ReplaceElementsAt(0, Length(), aData.Elements(), aData.Length(),
  18                            fallible);
  19 }
  20
  21 uint8_t* CryptoBuffer::Assign(const uint8_t* aData, uint32_t aLength) {
  22   return ReplaceElementsAt(0, Length(), aData, aLength, fallible);
  23 }
  24
  25 uint8_t* CryptoBuffer::Assign(const nsACString& aString) {
  26   return Assign(reinterpret_cast<uint8_t const*>(aString.BeginReading()),
  27                 aString.Length());
  28 }
  29
  30 uint8_t* CryptoBuffer::Assign(const SECItem* aItem) {
  31   MOZ_ASSERT(aItem);
  32   return Assign(aItem->data, aItem->len);
  33 }
  34
  35 uint8_t* CryptoBuffer::Assign(const nsTArray<uint8_t>& aData) {
  36   return ReplaceElementsAt(0, Length(), aData.Elements(), aData.Length(),
  37                            fallible);
  38 }
  39
  40 uint8_t* CryptoBuffer::Assign(const ArrayBuffer& aData) {
  41   aData.ComputeState();
  42   return Assign(aData.Data(), aData.Length());
  43 }
  44
  45 uint8_t* CryptoBuffer::Assign(const ArrayBufferView& aData) {
  46   aData.ComputeState();
  47   return Assign(aData.Data(), aData.Length());
  48 }
  49
  50 uint8_t* CryptoBuffer::Assign(const ArrayBufferViewOrArrayBuffer& aData) {
  51   if (aData.IsArrayBufferView()) {
  52     return Assign(aData.GetAsArrayBufferView());
  53   }
  54   if (aData.IsArrayBuffer()) {
  55     return Assign(aData.GetAsArrayBuffer());
  56   }
  57
  58   // If your union is uninitialized, something's wrong
  59   MOZ_ASSERT(false);
  60   Clear();
  61   return nullptr;
  62 }
  63
  64 uint8_t* CryptoBuffer::Assign(const OwningArrayBufferViewOrArrayBuffer& aData) {
  65   if (aData.IsArrayBufferView()) {
  66     return Assign(aData.GetAsArrayBufferView());
  67   }
  68   if (aData.IsArrayBuffer()) {
  69     return Assign(aData.GetAsArrayBuffer());
  70   }
  71
  72   // If your union is uninitialized, something's wrong
  73   MOZ_ASSERT(false);
  74   Clear();
  75   return nullptr;
  76 }
  77
  78 uint8_t* CryptoBuffer::Assign(const Uint8Array& aArray) {
  79   aArray.ComputeState();
  80   return Assign(aArray.Data(), aArray.Length());
  81 }
  82
  83 uint8_t* CryptoBuffer::AppendSECItem(const SECItem* aItem) {
  84   MOZ_ASSERT(aItem);
  85   return AppendElements(aItem->data, aItem->len, fallible);
  86 }
  87
  88 uint8_t* CryptoBuffer::AppendSECItem(const SECItem& aItem) {
  89   return AppendElements(aItem.data, aItem.len, fallible);
  90 }
  91
  92 // Helpers to encode/decode JWK's special flavor of Base64
  93 // * No whitespace
  94 // * No padding
  95 // * URL-safe character set
  96 nsresult CryptoBuffer::FromJwkBase64(const nsString& aBase64) {
  97   NS_ConvertUTF16toUTF8 temp(aBase64);
  98   temp.StripWhitespace();
  99
 100   // JWK prohibits padding per RFC 7515, section 2.
 101   nsresult rv =
 102       Base64URLDecode(temp, Base64URLDecodePaddingPolicy::Reject, *this);
 103   NS_ENSURE_SUCCESS(rv, rv);
 104
 105   return NS_OK;
 106 }
 107
 108 nsresult CryptoBuffer::ToJwkBase64(nsString& aBase64) const {
 109   // Shortcut for the empty octet string
 110   if (Length() == 0) {
 111     aBase64.Truncate();
 112     return NS_OK;
 113   }
 114
 115   nsAutoCString base64;
 116   nsresult rv = Base64URLEncode(Length(), Elements(),
 117                                 Base64URLEncodePaddingPolicy::Omit, base64);
 118   NS_ENSURE_SUCCESS(rv, rv);
 119
 120   CopyASCIItoUTF16(base64, aBase64);
 121   return NS_OK;
 122 }
 123
 124 bool CryptoBuffer::ToSECItem(PLArenaPool* aArena, SECItem* aItem) const {
 125   aItem->type = siBuffer;
 126   aItem->data = nullptr;
 127
 128   if (!::SECITEM_AllocItem(aArena, aItem, Length())) {
 129     return false;
 130   }
 131
 132   memcpy(aItem->data, Elements(), Length());
 133   return true;
 134 }
 135
 136 JSObject* CryptoBuffer::ToUint8Array(JSContext* aCx) const {
 137   return Uint8Array::Create(aCx, Length(), Elements());
 138 }
 139
 140 JSObject* CryptoBuffer::ToArrayBuffer(JSContext* aCx) const {
 141   return ArrayBuffer::Create(aCx, Length(), Elements());
 142 }
 143
 144 bool CryptoBuffer::ToNewUnsignedBuffer(uint8_t** aBuf,
 145                                        uint32_t* aBufLen) const {
 146   MOZ_ASSERT(aBuf);
 147   MOZ_ASSERT(aBufLen);
 148
 149   uint32_t dataLen = Length();
 150   uint8_t* tmp = reinterpret_cast<uint8_t*>(moz_xmalloc(dataLen));
 151
 152   memcpy(tmp, Elements(), dataLen);
 153   *aBuf = tmp;
 154   *aBufLen = dataLen;
 155   return true;
 156 }
 157
 158 // "BigInt" comes from the WebCrypto spec
 159 // ("unsigned long" isn't very "big", of course)
 160 // Likewise, the spec calls for big-endian ints
 161 bool CryptoBuffer::GetBigIntValue(unsigned long& aRetVal) {
 162   if (Length() > sizeof(aRetVal)) {
 163     return false;
 164   }
 165
 166   aRetVal = 0;
 167   for (size_t i = 0; i < Length(); ++i) {
 168     aRetVal = (aRetVal << 8) + ElementAt(i);
 169   }
 170   return true;
 171 }
 172
 173 }  // namespace mozilla::dom