| // Copyright 2014 The PDFium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com |
| |
| #include "core/fdrm/fx_crypt.h" |
| |
| #include <utility> |
| |
| #include "core/fxcrt/byteorder.h" |
| #include "core/fxcrt/compiler_specific.h" |
| #include "core/fxcrt/stl_util.h" |
| |
| namespace { |
| |
| const uint8_t md5_padding[64] = { |
| 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; |
| |
| void md5_process(CRYPT_md5_context* ctx, pdfium::span<const uint8_t, 64> data) { |
| uint32_t X[16] = { |
| fxcrt::GetUInt32LSBFirst(data.subspan<0, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<4, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<8, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<12, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<16, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<20, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<24, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<28, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<32, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<36, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<40, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<44, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<48, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<52, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<56, 4>()), |
| fxcrt::GetUInt32LSBFirst(data.subspan<60, 4>()), |
| }; |
| uint32_t A = ctx->state[0]; |
| uint32_t B = ctx->state[1]; |
| uint32_t C = ctx->state[2]; |
| uint32_t D = ctx->state[3]; |
| #define S(x, n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n))) |
| #define P(a, b, c, d, k, s, t) \ |
| { \ |
| a += F(b, c, d) + X[k] + t; \ |
| a = S(a, s) + b; \ |
| } |
| #define F(x, y, z) (z ^ (x & (y ^ z))) |
| P(A, B, C, D, 0, 7, 0xD76AA478); |
| P(D, A, B, C, 1, 12, 0xE8C7B756); |
| P(C, D, A, B, 2, 17, 0x242070DB); |
| P(B, C, D, A, 3, 22, 0xC1BDCEEE); |
| P(A, B, C, D, 4, 7, 0xF57C0FAF); |
| P(D, A, B, C, 5, 12, 0x4787C62A); |
| P(C, D, A, B, 6, 17, 0xA8304613); |
| P(B, C, D, A, 7, 22, 0xFD469501); |
| P(A, B, C, D, 8, 7, 0x698098D8); |
| P(D, A, B, C, 9, 12, 0x8B44F7AF); |
| P(C, D, A, B, 10, 17, 0xFFFF5BB1); |
| P(B, C, D, A, 11, 22, 0x895CD7BE); |
| P(A, B, C, D, 12, 7, 0x6B901122); |
| P(D, A, B, C, 13, 12, 0xFD987193); |
| P(C, D, A, B, 14, 17, 0xA679438E); |
| P(B, C, D, A, 15, 22, 0x49B40821); |
| #undef F |
| #define F(x, y, z) (y ^ (z & (x ^ y))) |
| P(A, B, C, D, 1, 5, 0xF61E2562); |
| P(D, A, B, C, 6, 9, 0xC040B340); |
| P(C, D, A, B, 11, 14, 0x265E5A51); |
| P(B, C, D, A, 0, 20, 0xE9B6C7AA); |
| P(A, B, C, D, 5, 5, 0xD62F105D); |
| P(D, A, B, C, 10, 9, 0x02441453); |
| P(C, D, A, B, 15, 14, 0xD8A1E681); |
| P(B, C, D, A, 4, 20, 0xE7D3FBC8); |
| P(A, B, C, D, 9, 5, 0x21E1CDE6); |
| P(D, A, B, C, 14, 9, 0xC33707D6); |
| P(C, D, A, B, 3, 14, 0xF4D50D87); |
| P(B, C, D, A, 8, 20, 0x455A14ED); |
| P(A, B, C, D, 13, 5, 0xA9E3E905); |
| P(D, A, B, C, 2, 9, 0xFCEFA3F8); |
| P(C, D, A, B, 7, 14, 0x676F02D9); |
| P(B, C, D, A, 12, 20, 0x8D2A4C8A); |
| #undef F |
| #define F(x, y, z) (x ^ y ^ z) |
| P(A, B, C, D, 5, 4, 0xFFFA3942); |
| P(D, A, B, C, 8, 11, 0x8771F681); |
| P(C, D, A, B, 11, 16, 0x6D9D6122); |
| P(B, C, D, A, 14, 23, 0xFDE5380C); |
| P(A, B, C, D, 1, 4, 0xA4BEEA44); |
| P(D, A, B, C, 4, 11, 0x4BDECFA9); |
| P(C, D, A, B, 7, 16, 0xF6BB4B60); |
| P(B, C, D, A, 10, 23, 0xBEBFBC70); |
| P(A, B, C, D, 13, 4, 0x289B7EC6); |
| P(D, A, B, C, 0, 11, 0xEAA127FA); |
| P(C, D, A, B, 3, 16, 0xD4EF3085); |
| P(B, C, D, A, 6, 23, 0x04881D05); |
| P(A, B, C, D, 9, 4, 0xD9D4D039); |
| P(D, A, B, C, 12, 11, 0xE6DB99E5); |
| P(C, D, A, B, 15, 16, 0x1FA27CF8); |
| P(B, C, D, A, 2, 23, 0xC4AC5665); |
| #undef F |
| #define F(x, y, z) (y ^ (x | ~z)) |
| P(A, B, C, D, 0, 6, 0xF4292244); |
| P(D, A, B, C, 7, 10, 0x432AFF97); |
| P(C, D, A, B, 14, 15, 0xAB9423A7); |
| P(B, C, D, A, 5, 21, 0xFC93A039); |
| P(A, B, C, D, 12, 6, 0x655B59C3); |
| P(D, A, B, C, 3, 10, 0x8F0CCC92); |
| P(C, D, A, B, 10, 15, 0xFFEFF47D); |
| P(B, C, D, A, 1, 21, 0x85845DD1); |
| P(A, B, C, D, 8, 6, 0x6FA87E4F); |
| P(D, A, B, C, 15, 10, 0xFE2CE6E0); |
| P(C, D, A, B, 6, 15, 0xA3014314); |
| P(B, C, D, A, 13, 21, 0x4E0811A1); |
| P(A, B, C, D, 4, 6, 0xF7537E82); |
| P(D, A, B, C, 11, 10, 0xBD3AF235); |
| P(C, D, A, B, 2, 15, 0x2AD7D2BB); |
| P(B, C, D, A, 9, 21, 0xEB86D391); |
| #undef F |
| ctx->state[0] += A; |
| ctx->state[1] += B; |
| ctx->state[2] += C; |
| ctx->state[3] += D; |
| } |
| |
| } // namespace |
| |
| void CRYPT_ArcFourSetup(CRYPT_rc4_context* context, |
| pdfium::span<const uint8_t> key) { |
| context->x = 0; |
| context->y = 0; |
| for (int i = 0; i < CRYPT_rc4_context::kPermutationLength; ++i) |
| context->m[i] = i; |
| |
| int j = 0; |
| for (int i = 0; i < CRYPT_rc4_context::kPermutationLength; ++i) { |
| size_t size = key.size(); |
| j = (j + context->m[i] + (size ? key[i % size] : 0)) & 0xFF; |
| std::swap(context->m[i], context->m[j]); |
| } |
| } |
| |
| void CRYPT_ArcFourCrypt(CRYPT_rc4_context* context, |
| pdfium::span<uint8_t> data) { |
| for (auto& datum : data) { |
| context->x = (context->x + 1) & 0xFF; |
| context->y = (context->y + context->m[context->x]) & 0xFF; |
| std::swap(context->m[context->x], context->m[context->y]); |
| datum ^= |
| context->m[(context->m[context->x] + context->m[context->y]) & 0xFF]; |
| } |
| } |
| |
| void CRYPT_ArcFourCryptBlock(pdfium::span<uint8_t> data, |
| pdfium::span<const uint8_t> key) { |
| CRYPT_rc4_context s; |
| CRYPT_ArcFourSetup(&s, key); |
| CRYPT_ArcFourCrypt(&s, data); |
| } |
| |
| CRYPT_md5_context CRYPT_MD5Start() { |
| CRYPT_md5_context context; |
| context.total[0] = 0; |
| context.total[1] = 0; |
| context.state[0] = 0x67452301; |
| context.state[1] = 0xEFCDAB89; |
| context.state[2] = 0x98BADCFE; |
| context.state[3] = 0x10325476; |
| return context; |
| } |
| |
| void CRYPT_MD5Update(CRYPT_md5_context* context, |
| pdfium::span<const uint8_t> data) { |
| if (data.empty()) |
| return; |
| |
| uint32_t left = (context->total[0] >> 3) & 0x3F; |
| uint32_t fill = 64 - left; |
| context->total[0] += data.size() << 3; |
| context->total[1] += data.size() >> 29; |
| context->total[0] &= 0xFFFFFFFF; |
| context->total[1] += context->total[0] < data.size() << 3; |
| |
| const pdfium::span<uint8_t> buffer_span = pdfium::make_span(context->buffer); |
| if (left && data.size() >= fill) { |
| fxcrt::Copy(data.first(fill), buffer_span.subspan(left)); |
| md5_process(context, context->buffer); |
| data = data.subspan(fill); |
| left = 0; |
| } |
| while (data.size() >= 64) { |
| md5_process(context, data.first(64)); |
| data = data.subspan(64); |
| } |
| if (!data.empty()) { |
| fxcrt::Copy(data, buffer_span.subspan(left)); |
| } |
| } |
| |
| void CRYPT_MD5Finish(CRYPT_md5_context* context, |
| pdfium::span<uint8_t, 16> digest) { |
| uint8_t msglen[8]; |
| auto msglen_span = pdfium::make_span(msglen); |
| fxcrt::PutUInt32LSBFirst(context->total[0], msglen_span.subspan<0, 4>()); |
| fxcrt::PutUInt32LSBFirst(context->total[1], msglen_span.subspan<4, 4>()); |
| uint32_t last = (context->total[0] >> 3) & 0x3F; |
| uint32_t padn = (last < 56) ? (56 - last) : (120 - last); |
| CRYPT_MD5Update(context, pdfium::make_span(md5_padding).first(padn)); |
| CRYPT_MD5Update(context, msglen); |
| fxcrt::PutUInt32LSBFirst(context->state[0], digest.subspan<0, 4>()); |
| fxcrt::PutUInt32LSBFirst(context->state[1], digest.subspan<4, 4>()); |
| fxcrt::PutUInt32LSBFirst(context->state[2], digest.subspan<8, 4>()); |
| fxcrt::PutUInt32LSBFirst(context->state[3], digest.subspan<12, 4>()); |
| } |
| |
| void CRYPT_MD5Generate(pdfium::span<const uint8_t> data, |
| pdfium::span<uint8_t, 16> digest) { |
| CRYPT_md5_context ctx = CRYPT_MD5Start(); |
| CRYPT_MD5Update(&ctx, data); |
| CRYPT_MD5Finish(&ctx, digest); |
| } |