From e1e735c4ff1a139ada263b2a06da74f63c61c78f Mon Sep 17 00:00:00 2001 From: notmasteryet Date: Wed, 20 Jul 2011 23:08:08 -0500 Subject: [PATCH 1/2] AES algorithm implementation, PDF1.5,1.6 crypto functionality --- crypto.js | 331 ++++++++++++++++++++++++++++++++++++++++++++++++++---- pdf.js | 1 - 2 files changed, 312 insertions(+), 20 deletions(-) diff --git a/crypto.js b/crypto.js index c60590777..98f7bb4a1 100644 --- a/crypto.js +++ b/crypto.js @@ -40,6 +40,7 @@ var ARCFourCipher = (function() { return output; } }; + constructor.prototype.decryptBlock = constructor.prototype.encryptBlock; return constructor; })(); @@ -128,6 +129,245 @@ var md5 = (function() { return hash; })(); +var NullCipher = (function() { + function constructor() { + } + + constructor.prototype = { + decryptBlock: function(data) { + return data; + } + }; + + return constructor; +})(); + +var AES128Cipher = (function() { + var rcon = new Uint8Array([ + 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, + 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, + 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, + 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, + 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, + 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, + 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, + 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, + 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, + 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, + 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, + 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, + 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, + 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, + 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, + 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d]); + + var s = new Uint8Array([ + 0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76, + 0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0, + 0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15, + 0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75, + 0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84, + 0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF, + 0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8, + 0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2, + 0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73, + 0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB, + 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, + 0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08, + 0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A, + 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E, + 0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF, + 0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16]); + + var inv_s = new Uint8Array([ + 0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB, + 0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB, + 0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E, + 0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25, + 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92, + 0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84, + 0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06, + 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02, 0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, + 0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73, + 0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E, + 0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, + 0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4, + 0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F, + 0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF, + 0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61, + 0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D]); + + var mix = new Uint32Array([ + 0x0, 0xe090d0b, 0x1c121a16, 0x121b171d, 0x3824342c, 0x362d3927, 0x24362e3a, + 0x2a3f2331, 0x70486858, 0x7e416553, 0x6c5a724e, 0x62537f45, 0x486c5c74, + 0x4665517f, 0x547e4662, 0x5a774b69, 0xe090d0b0, 0xee99ddbb, 0xfc82caa6, + 0xf28bc7ad, 0xd8b4e49c, 0xd6bde997, 0xc4a6fe8a, 0xcaaff381, 0x90d8b8e8, + 0x9ed1b5e3, 0x8ccaa2fe, 0x82c3aff5, 0xa8fc8cc4, 0xa6f581cf, 0xb4ee96d2, + 0xbae79bd9, 0xdb3bbb7b, 0xd532b670, 0xc729a16d, 0xc920ac66, 0xe31f8f57, + 0xed16825c, 0xff0d9541, 0xf104984a, 0xab73d323, 0xa57ade28, 0xb761c935, + 0xb968c43e, 0x9357e70f, 0x9d5eea04, 0x8f45fd19, 0x814cf012, 0x3bab6bcb, + 0x35a266c0, 0x27b971dd, 0x29b07cd6, 0x38f5fe7, 0xd8652ec, 0x1f9d45f1, + 0x119448fa, 0x4be30393, 0x45ea0e98, 0x57f11985, 0x59f8148e, 0x73c737bf, + 0x7dce3ab4, 0x6fd52da9, 0x61dc20a2, 0xad766df6, 0xa37f60fd, 0xb16477e0, + 0xbf6d7aeb, 0x955259da, 0x9b5b54d1, 0x894043cc, 0x87494ec7, 0xdd3e05ae, + 0xd33708a5, 0xc12c1fb8, 0xcf2512b3, 0xe51a3182, 0xeb133c89, 0xf9082b94, + 0xf701269f, 0x4de6bd46, 0x43efb04d, 0x51f4a750, 0x5ffdaa5b, 0x75c2896a, + 0x7bcb8461, 0x69d0937c, 0x67d99e77, 0x3daed51e, 0x33a7d815, 0x21bccf08, + 0x2fb5c203, 0x58ae132, 0xb83ec39, 0x1998fb24, 0x1791f62f, 0x764dd68d, + 0x7844db86, 0x6a5fcc9b, 0x6456c190, 0x4e69e2a1, 0x4060efaa, 0x527bf8b7, + 0x5c72f5bc, 0x605bed5, 0x80cb3de, 0x1a17a4c3, 0x141ea9c8, 0x3e218af9, + 0x302887f2, 0x223390ef, 0x2c3a9de4, 0x96dd063d, 0x98d40b36, 0x8acf1c2b, + 0x84c61120, 0xaef93211, 0xa0f03f1a, 0xb2eb2807, 0xbce2250c, 0xe6956e65, + 0xe89c636e, 0xfa877473, 0xf48e7978, 0xdeb15a49, 0xd0b85742, 0xc2a3405f, + 0xccaa4d54, 0x41ecdaf7, 0x4fe5d7fc, 0x5dfec0e1, 0x53f7cdea, 0x79c8eedb, + 0x77c1e3d0, 0x65daf4cd, 0x6bd3f9c6, 0x31a4b2af, 0x3fadbfa4, 0x2db6a8b9, + 0x23bfa5b2, 0x9808683, 0x7898b88, 0x15929c95, 0x1b9b919e, 0xa17c0a47, + 0xaf75074c, 0xbd6e1051, 0xb3671d5a, 0x99583e6b, 0x97513360, 0x854a247d, + 0x8b432976, 0xd134621f, 0xdf3d6f14, 0xcd267809, 0xc32f7502, 0xe9105633, + 0xe7195b38, 0xf5024c25, 0xfb0b412e, 0x9ad7618c, 0x94de6c87, 0x86c57b9a, + 0x88cc7691, 0xa2f355a0, 0xacfa58ab, 0xbee14fb6, 0xb0e842bd, 0xea9f09d4, + 0xe49604df, 0xf68d13c2, 0xf8841ec9, 0xd2bb3df8, 0xdcb230f3, 0xcea927ee, + 0xc0a02ae5, 0x7a47b13c, 0x744ebc37, 0x6655ab2a, 0x685ca621, 0x42638510, + 0x4c6a881b, 0x5e719f06, 0x5078920d, 0xa0fd964, 0x406d46f, 0x161dc372, + 0x1814ce79, 0x322bed48, 0x3c22e043, 0x2e39f75e, 0x2030fa55, 0xec9ab701, + 0xe293ba0a, 0xf088ad17, 0xfe81a01c, 0xd4be832d, 0xdab78e26, 0xc8ac993b, + 0xc6a59430, 0x9cd2df59, 0x92dbd252, 0x80c0c54f, 0x8ec9c844, 0xa4f6eb75, + 0xaaffe67e, 0xb8e4f163, 0xb6edfc68, 0xc0a67b1, 0x2036aba, 0x10187da7, + 0x1e1170ac, 0x342e539d, 0x3a275e96, 0x283c498b, 0x26354480, 0x7c420fe9, + 0x724b02e2, 0x605015ff, 0x6e5918f4, 0x44663bc5, 0x4a6f36ce, 0x587421d3, + 0x567d2cd8, 0x37a10c7a, 0x39a80171, 0x2bb3166c, 0x25ba1b67, 0xf853856, + 0x18c355d, 0x13972240, 0x1d9e2f4b, 0x47e96422, 0x49e06929, 0x5bfb7e34, + 0x55f2733f, 0x7fcd500e, 0x71c45d05, 0x63df4a18, 0x6dd64713, 0xd731dcca, + 0xd938d1c1, 0xcb23c6dc, 0xc52acbd7, 0xef15e8e6, 0xe11ce5ed, 0xf307f2f0, + 0xfd0efffb, 0xa779b492, 0xa970b999, 0xbb6bae84, 0xb562a38f, 0x9f5d80be, + 0x91548db5, 0x834f9aa8, 0x8d4697a3]); + + function expandKey128(cipherKey) { + var b = 176, result = new Uint8Array(b); + result.set(cipherKey); + for (var j = 16, i = 1; j < b; ++i) { + // RotWord + var t1 = result[j - 3], t2 = result[j - 2], t3 = result[j - 1], t4 = result[j - 4]; + // SubWord + t1 = s[t1]; t2 = s[t2]; t3 = s[t3]; t4 = s[t4]; + // Rcon + t1 = t1 ^ rcon[i]; + for (var n = 0; n < 4; ++n) { + result[j] = (t1 ^= result[j - 16]); j++; + result[j] = (t2 ^= result[j - 16]); j++; + result[j] = (t3 ^= result[j - 16]); j++; + result[j] = (t4 ^= result[j - 16]); j++; + } + } + return result; + } + + function decrypt128(input, key) { + var state = new Uint8Array(16); + state.set(input); + var i, j, k; + var t, u, v; + // AddRoundKey + for (j = 0, k = 160; j < 16; ++j, ++k) + state[j] ^= key[k]; + for (i = 9; i >= 1; --i) { + // InvShiftRows + t = state[13]; state[13] = state[9]; state[9] = state[5]; state[5] = state[1]; state[1] = t; + t = state[14]; u = state[10]; state[14] = state[6]; state[10] = state[2]; state[6] = t; state[2] = u; + t = state[15]; u = state[11]; v = state[7]; state[15] = state[3]; state[11] = t; state[7] = u; state[3] = v; + // InvSubBytes + for (j = 0; j < 16; ++j) + state[j] = inv_s[state[j]]; + // AddRoundKey + for (j = 0, k = i * 16; j < 16; ++j, ++k) + state[j] ^= key[k]; + // InvMixColumns + for (j = 0; j < 16; j += 4) { + var s0 = mix[state[j]], s1 = mix[state[j + 1]], s2 = mix[state[j + 2]], s3 = mix[state[j + 3]]; + t = s0 ^ (s1 >>> 8) ^ (s1 << 24) ^ (s2 >>> 16) ^ (s2 << 16) ^ (s3 >>> 24) ^ (s3 << 8); + state[j] = (t >>> 24) & 0xFF; + state[j + 1] = (t >> 16) & 0xFF; + state[j + 2] = (t >> 8) & 0xFF; + state[j + 3] = t & 0xFF; + } + } + // InvShiftRows + t = state[13]; state[13] = state[9]; state[9] = state[5]; state[5] = state[1]; state[1] = t; + t = state[14]; u = state[10]; state[14] = state[6]; state[10] = state[2]; state[6] = t; state[2] = u; + t = state[15]; u = state[11]; v = state[7]; state[15] = state[3]; state[11] = t; state[7] = u; state[3] = v; + // InvSubBytes + for (j = 0; j < 16; ++j) + state[j] = inv_s[state[j]]; + // AddRoundKey + for (j = 0; j < 16; ++j) + state[j] ^= key[j]; + return state; + } + + function constructor(key) { + this.key = expandKey128(key); + this.buffer = new Uint8Array(16); + this.bufferPosition = 0; + } + + function decryptBlock2(data) { + var i, j, sourceLength = data.length; + var buffer = this.buffer, bufferLength = this.bufferPosition, iv = this.iv; + var result = []; + for (i = 0; i < sourceLength; ++i) { + buffer[bufferLength] = data[i]; + ++bufferLength; + if (bufferLength < 16) + continue; + // buffer is full, decrypting + var plain = decrypt128(buffer, this.key); + // xor-ing the IV vector to get plain text + for (j = 0; j < 16; ++j) + plain[j] ^= iv[j]; + iv = buffer; + result.push(plain); + buffer = new Uint8Array(16); + bufferLength = 0; + } + // saving incomplete buffer + this.buffer = buffer; + this.bufferLength = bufferLength; + this.iv = iv; + if (result.length == 0) + return new Uint8Array([]); + if (result.length == 1) + return result[0]; + // combining plain text blocks into one + var output = new Uint8Array(16 * result.length); + for (i = 0, j = 0; i < result.length; ++i, j += 16) + output.set(result[i], j); + return output; + } + + constructor.prototype = { + decryptBlock: function(data) { + var i, sourceLength = data.length; + var buffer = this.buffer, bufferLength = this.bufferPosition; + // waiting for IV values -- they are at the start of the stream + for (i = 0; bufferLength < 16 && i < sourceLength; ++i, ++bufferLength) + buffer[bufferLength] = data[i]; + if (bufferLength < 16) { + // need more data + this.bufferLength = bufferLength; + return new Uint8Array([]); + } + this.iv = buffer; + this.buffer = new Uint8Array(16); + this.bufferLength = 0; + // starting decryption + this.decryptBlock = decryptBlock2; + return this.decryptBlock(data.subarray(16)); + } + }; + + return constructor; +})(); + var CipherTransform = (function() { function constructor(stringCipherConstructor, streamCipherConstructor) { this.stringCipherConstructor = stringCipherConstructor; @@ -137,13 +377,13 @@ var CipherTransform = (function() { createStream: function(stream) { var cipher = new this.streamCipherConstructor(); return new DecryptStream(stream, function(data) { - return cipher.encryptBlock(data); + return cipher.decryptBlock(data); }); }, decryptString: function(s) { var cipher = new this.stringCipherConstructor(); var data = stringToBytes(s); - data = cipher.encryptBlock(data); + data = cipher.decryptBlock(data); return bytesToString(data); } }; @@ -152,13 +392,13 @@ var CipherTransform = (function() { var CipherTransformFactory = (function() { function prepareKeyData(fileId, password, ownerPassword, userPassword, - flags, revision, keyLength) { + flags, revision, keyLength, encryptMetadata) { var defaultPasswordBytes = new Uint8Array([ 0x28, 0xBF, 0x4E, 0x5E, 0x4E, 0x75, 0x8A, 0x41, 0x64, 0x00, 0x4E, 0x56, 0xFF, 0xFA, 0x01, 0x08, 0x2E, 0x2E, 0x00, 0xB6, 0xD0, 0x68, 0x3E, 0x80, 0x2F, 0x0C, 0xA9, 0xFE, 0x64, 0x53, 0x69, 0x7A]); - var hashData = new Uint8Array(88), i = 0, j, n; + var hashData = new Uint8Array(100), i = 0, j, n; if (password) { n = Math.min(32, password.length); for (; i < n; ++i) @@ -177,7 +417,12 @@ var CipherTransformFactory = (function() { hashData[i++] = (flags >>> 24) & 0xFF; for (j = 0, n = fileId.length; j < n; ++j) hashData[i++] = fileId[j]; - // TODO rev 4, if metadata is not encrypted pass 0xFFFFFF also + if (revision >= 4 && !encryptMetadata) { + hashData[i++] = 0xFF; + hashData[i++] = 0xFF; + hashData[i++] = 0xFF; + hashData[i++] = 0xFF; + } var hash = md5(hashData, 0, i); var keyLengthInBytes = keyLength >> 3; if (revision >= 3) { @@ -215,6 +460,8 @@ var CipherTransformFactory = (function() { return encryptionKey; } + var identityName = new Name('Identity'); + function constructor(dict, fileId, password) { var filter = dict.get('Filter'); if (!IsName(filter) || filter.name != 'Standard') @@ -222,9 +469,9 @@ var CipherTransformFactory = (function() { this.dict = dict; var algorithm = dict.get('V'); if (!IsInt(algorithm) || - (algorithm != 1 && algorithm != 2)) + (algorithm != 1 && algorithm != 2 && algorithm != 4)) error('unsupported encryption algorithm'); - // TODO support algorithm 4 + this.algorithm = algorithm; var keyLength = dict.get('Length') || 40; if (!IsInt(keyLength) || keyLength < 40 || (keyLength % 8) != 0) @@ -234,6 +481,7 @@ var CipherTransformFactory = (function() { var userPassword = stringToBytes(dict.get('U')); var flags = dict.get('P'); var revision = dict.get('R'); + var encryptMetadata = dict.get('EncryptMetadata') !== false; // makes true as default value var fileIdBytes = stringToBytes(fileId); var passwordBytes; if (password) @@ -241,22 +489,67 @@ var CipherTransformFactory = (function() { this.encryptionKey = prepareKeyData(fileIdBytes, passwordBytes, ownerPassword, userPassword, - flags, revision, keyLength); + flags, revision, keyLength, encryptMetadata); + if (algorithm == 4) { + this.cf = dict.get('CF'); + this.stmf = dict.get('StmF') || identityName; + this.strf = dict.get('StrF') || identityName; + this.eff = dict.get('EFF') || this.strf; + } + } + + function buildObjectKey(num, gen, encryptionKey, isAes) { + var key = new Uint8Array(encryptionKey.length + 9), i, n; + for (i = 0, n = encryptionKey.length; i < n; ++i) + key[i] = encryptionKey[i]; + key[i++] = num & 0xFF; + key[i++] = (num >> 8) & 0xFF; + key[i++] = (num >> 16) & 0xFF; + key[i++] = gen & 0xFF; + key[i++] = (gen >> 8) & 0xFF; + if (isAes) { + key[i++] = 0x73; + key[i++] = 0x41; + key[i++] = 0x6C; + key[i++] = 0x54; + } + var hash = md5(key, 0, i); + return hash.subarray(0, Math.min(key.length, 16)); + } + + function buildCipherConstructor(cf, name, num, gen, key) { + var cryptFilter = cf.get(name.name); + var cfm; + if (cryptFilter != null) + cfm = cryptFilter.get('CFM'); + if (!cfm || cfm.name == 'None') { + return function() { + return new NullCipher(); + }; + } + if ('V2' == cfm.name) { + return function() { + return new ARCFourCipher( + buildObjectKey(num, gen, key, false)); + }; + } + if ('AESV2' == cfm.name) { + return function() { + return new AES128Cipher( + buildObjectKey(num, gen, key, true)); + }; + } } constructor.prototype = { createCipherTransform: function(num, gen) { - var encryptionKey = this.encryptionKey; - var key = new Uint8Array(encryptionKey.length + 5), i, n; - for (i = 0, n = encryptionKey.length; i < n; ++i) - key[i] = encryptionKey[i]; - key[i++] = num & 0xFF; - key[i++] = (num >> 8) & 0xFF; - key[i++] = (num >> 16) & 0xFF; - key[i++] = gen & 0xFF; - key[i++] = (gen >> 8) & 0xFF; - var hash = md5(key, 0, i); - key = hash.subarray(0, Math.min(key.length, 16)); + if (this.algorithm == 4) { + return new CipherTransform( + buildCipherConstructor(this.cf, this.stmf, num, gen, this.encryptionKey), + buildCipherConstructor(this.cf, this.strf, num, gen, this.encryptionKey)); + } + // algorithms 1 and 2 + var key = buildObjectKey(num, gen, this.encryptionKey, false); var cipherConstructor = function() { return new ARCFourCipher(key); }; diff --git a/pdf.js b/pdf.js index a3179406c..df8e3f3cc 100644 --- a/pdf.js +++ b/pdf.js @@ -829,7 +829,6 @@ var DecryptStream = (function() { for (i = 0; i < n; i++) buffer[bufferLength++] = chunk[i]; this.bufferLength = bufferLength; - this.eof = n < chunkSize; }; return constructor; From e9df0bb8caa7484eb4eff81051f3e0294dc068e2 Mon Sep 17 00:00:00 2001 From: notmasteryet Date: Wed, 20 Jul 2011 23:17:31 -0500 Subject: [PATCH 2/2] link to AESV2 encrypted file --- test/pdfs/i9.pdf.link | 1 + test/test_manifest.json | 6 ++++++ 2 files changed, 7 insertions(+) create mode 100644 test/pdfs/i9.pdf.link diff --git a/test/pdfs/i9.pdf.link b/test/pdfs/i9.pdf.link new file mode 100644 index 000000000..a4a75e771 --- /dev/null +++ b/test/pdfs/i9.pdf.link @@ -0,0 +1 @@ +http://www.uscis.gov/files/form/i-9.pdf diff --git a/test/test_manifest.json b/test/test_manifest.json index 6c1ff71cd..c5c196397 100644 --- a/test/test_manifest.json +++ b/test/test_manifest.json @@ -63,5 +63,11 @@ "file": "pdfs/ArabicCIDTrueType.pdf", "rounds": 1, "type": "load" + }, + { "id": "i9-pdf", + "file": "pdfs/i9.pdf", + "link": true, + "rounds": 1, + "type": "eq" } ]