Issue 5146 - Implement DownloadableSubscription parsing in C++

compiled/Md5.cpp

+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-present eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* Original notice */
+/*
+ * This is an OpenSSL-compatible implementation of the RSA Data Security, Inc.
+ * MD5 Message-Digest Algorithm (RFC 1321).
+ *
+ * Homepage:
+ * http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5
+ *
+ * Author:
+ * Alexander Peslyak, better known as Solar Designer <solar at openwall.com>
+ *
+ * This software was written by Alexander Peslyak in 2001.  No copyright is
+ * claimed, and the software is hereby placed in the public domain.
+ * In case this attempt to disclaim copyright and place the software in the
+ * public domain is deemed null and void, then the software is
+ * Copyright (c) 2001 Alexander Peslyak and it is hereby released to the
+ * general public under the following terms:
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted.
+ *
+ * There's ABSOLUTELY NO WARRANTY, express or implied.
+ *
+ * (This is a heavily cut-down "BSD license".)
+ *
+ * This differs from Colin Plumb's older public domain implementation in that
+ * no exactly 32-bit integer data type is required (any 32-bit or wider
+ * unsigned integer data type will do), there's no compile-time endianness
+ * configuration, and the function prototypes match OpenSSL's.  No code from
+ * Colin Plumb's implementation has been reused; this comment merely compares
+ * the properties of the two independent implementations.
+ *
+ * The primary goals of this implementation are portability and ease of use.
+ * It is meant to be fast, but not as fast as possible.  Some known
+ * optimizations are not included to reduce source code size and avoid
+ * compile-time configuration.
+ */
+
+#include <string.h>
+
+#include "String.h"
+
+#include "Md5.h"
+
+/*
+ * The basic MD5 functions.
+ *
+ * F and G are optimized compared to their RFC 1321 definitions for
+ * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
+ * implementation.
+ */
+#define F(x, y, z)                      ((z) ^ ((x) & ((y) ^ (z))))
+#define G(x, y, z)                      ((y) ^ ((z) & ((x) ^ (y))))
+#define H(x, y, z)                      (((x) ^ (y)) ^ (z))
+#define H2(x, y, z)                     ((x) ^ ((y) ^ (z)))
+#define I(x, y, z)                      ((y) ^ ((x) | ~(z)))
+
+/*
+ * The MD5 transformation for all four rounds.
+ */
+#define STEP(f, a, b, c, d, x, t, s)                            \
+  (a) += f((b), (c), (d)) + (x) + (t);                          \
+  (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s))));    \
+  (a) += (b)
+
+/*
+ * SET reads 4 input bytes in little-endian byte order and stores them in a
+ * properly aligned word in host byte order.
+ *
+ * The check for little-endian architectures that tolerate unaligned memory
+ * accesses is just an optimization.  Nothing will break if it fails to detect
+ * a suitable architecture.
+ *
+ * Unfortunately, this optimization may be a C strict aliasing rules violation
+ * if the caller's data buffer has effective type that cannot be aliased by
+ * uint32_t.  In practice, this problem may occur if these MD5 routines are
+ * inlined into a calling function, or with future and dangerously advanced
+ * link-time optimizations.  For the time being, keeping these MD5 routines in
+ * their own translation unit avoids the problem.
+ */
+#if defined(__i386__) || defined(__x86_64__) || defined(__vax__)
+#define SET(n)                                  \
+  (*(uint32_t *)&ptr[(n) * 4])
+#define GET(n)                                  \
+  SET(n)
+#else
+#define SET(n)                                  \
+  (this->block[(n)] =                            \
+     (uint32_t)ptr[(n) * 4] |                \
+   ((uint32_t)ptr[(n) * 4 + 1] << 8) |       \
+   ((uint32_t)ptr[(n) * 4 + 2] << 16) |      \
+   ((uint32_t)ptr[(n) * 4 + 3] << 24))
+#define GET(n)                                  \
+  (this->block[(n)])
+#endif
+
+/*
+ * This processes one or more 64-byte data blocks, but does NOT update the bit
+ * counters.  There are no alignment requirements.
+ */
+const void *MD5::Body(const void *data, unsigned long size)
+{
+  const unsigned char *ptr;
+  uint32_t a, b, c, d;
+  uint32_t saved_a, saved_b, saved_c, saved_d;
+
+  ptr = (const unsigned char *)data;
+
+  a = this->a;
+  b = this->b;
+  c = this->c;
+  d = this->d;
+
+  do {
+    saved_a = a;
+    saved_b = b;
+    saved_c = c;
+    saved_d = d;
+
+/* Round 1 */
+    STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7);
+    STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12);
+    STEP(F, c, d, a, b, SET(2), 0x242070db, 17);
+    STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22);
+    STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7);
+    STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12);
+    STEP(F, c, d, a, b, SET(6), 0xa8304613, 17);
+    STEP(F, b, c, d, a, SET(7), 0xfd469501, 22);
+    STEP(F, a, b, c, d, SET(8), 0x698098d8, 7);
+    STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12);
+    STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17);
+    STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22);
+    STEP(F, a, b, c, d, SET(12), 0x6b901122, 7);
+    STEP(F, d, a, b, c, SET(13), 0xfd987193, 12);
+    STEP(F, c, d, a, b, SET(14), 0xa679438e, 17);
+    STEP(F, b, c, d, a, SET(15), 0x49b40821, 22);
+
+/* Round 2 */
+    STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5);
+    STEP(G, d, a, b, c, GET(6), 0xc040b340, 9);
+    STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14);
+    STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20);
+    STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5);
+    STEP(G, d, a, b, c, GET(10), 0x02441453, 9);
+    STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14);
+    STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20);
+    STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5);
+    STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9);
+    STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14);
+    STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20);
+    STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5);
+    STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9);
+    STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14);
+    STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20);
+
+/* Round 3 */
+    STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4);
+    STEP(H2, d, a, b, c, GET(8), 0x8771f681, 11);
+    STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16);
+    STEP(H2, b, c, d, a, GET(14), 0xfde5380c, 23);
+    STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4);
+    STEP(H2, d, a, b, c, GET(4), 0x4bdecfa9, 11);
+    STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16);
+    STEP(H2, b, c, d, a, GET(10), 0xbebfbc70, 23);
+    STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4);
+    STEP(H2, d, a, b, c, GET(0), 0xeaa127fa, 11);
+    STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16);
+    STEP(H2, b, c, d, a, GET(6), 0x04881d05, 23);
+    STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4);
+    STEP(H2, d, a, b, c, GET(12), 0xe6db99e5, 11);
+    STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16);
+    STEP(H2, b, c, d, a, GET(2), 0xc4ac5665, 23);
+
+/* Round 4 */
+    STEP(I, a, b, c, d, GET(0), 0xf4292244, 6);
+    STEP(I, d, a, b, c, GET(7), 0x432aff97, 10);
+    STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15);
+    STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21);
+    STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6);
+    STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10);
+    STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15);
+    STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21);
+    STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6);
+    STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10);
+    STEP(I, c, d, a, b, GET(6), 0xa3014314, 15);
+    STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21);
+    STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6);
+    STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10);
+    STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15);
+    STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21);
+
+    a += saved_a;
+    b += saved_b;
+    c += saved_c;
+    d += saved_d;
+
+    ptr += 64;
+  } while (size -= 64);
+
+  this->a = a;
+  this->b = b;
+  this->c = c;
+  this->d = d;
+
+  return ptr;
+}
+
+void MD5::InitState()
+{
+  a = 0x67452301;
+  b = 0xefcdab89;
+  c = 0x98badcfe;
+  d = 0x10325476;
+}
+
+MD5::MD5()
+  : lo(0), hi(0)
+{
+  InitState();
+}
+
+void MD5::Update(const void *data, size_t size)
+{
+  uint32_t saved_lo;
+  unsigned long used, available;
+
+  saved_lo = this->lo;
+  if ((this->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
+    this->hi++;
+  this->hi += size >> 29;
+
+  used = saved_lo & 0x3f;
+
+  if (used) {
+    available = 64 - used;
+
+    if (size < available) {
+      memcpy(&this->buffer[used], data, size);
+      return;
+    }
+
+    memcpy(&this->buffer[used], data, available);
+    data = (const unsigned char *)data + available;
+    size -= available;
+    Body(this->buffer, 64);
+  }
+
+  if (size >= 64) {
+    data = Body(data, size & ~(unsigned long)0x3f);
+    size &= 0x3f;
+  }
+
+  memcpy(this->buffer, data, size);
+}
+
+#define OUT(dst, src)                           \
+  (dst)[0] = (unsigned char)(src);              \
+  (dst)[1] = (unsigned char)((src) >> 8);       \
+  (dst)[2] = (unsigned char)((src) >> 16);      \
+  (dst)[3] = (unsigned char)((src) >> 24)
+
+void MD5::Final(uint8_t *result)
+{
+  unsigned long used, available;
+
+  used = this->lo & 0x3f;
+
+  this->buffer[used++] = 0x80;
+
+  available = 64 - used;
+
+  if (available < 8) {
+    memset(&this->buffer[used], 0, available);
+    Body(this->buffer, 64);
+    used = 0;
+    available = 64;
+  }
+
+  memset(&this->buffer[used], 0, available - 8);
+
+  this->lo <<= 3;
+  OUT(&this->buffer[56], this->lo);
+  OUT(&this->buffer[60], this->hi);
+
+  Body(this->buffer, 64);
+
+  OUT(&result[0], this->a);
+  OUT(&result[4], this->b);
+  OUT(&result[8], this->c);
+  OUT(&result[12], this->d);
+
+  // Clear the data.
+  lo = hi = 0;
+  InitState();
+  memset(&buffer, 0, sizeof(*buffer));
+  memset(&block, 0, sizeof(*block));
+}
+
+void MD5::Update(const String& input)
+{
+  uint8_t utf8[] = { 0, 0, 0 };
+  size_t len = 0;
+
+  for (String::size_type i = 0; i < input.length(); i++)
+  {
+    // convert the string it utf-8
+    // String::value_type is only 16-bits for now.
+    // Update this code if we change it.
+    auto ch = input[i];
+    if (ch <= 0x7f)
+    {
+      utf8[0] = ch;
+      len = 1;
+    }
+    else if (ch <= 0x7ff)
+    {
+      utf8[0] = ((ch >> 6) & 0x1f) | 0xc0;
+      utf8[1] = (ch & 0x3f) | 0x80;
+      len = 2;
+    }
+    else
+    {
+      utf8[0] = ((ch >> 12) & 0x0f) | 0xe0;
+      utf8[1] = ((ch >> 6) & 0x3f) | 0x80;
+      utf8[2] = (ch & 0x3f) | 0x80;
+      len = 3;
+    }
+    Update(utf8, len);
+  }
+}