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Save work on AES and RC4.
This commit is contained in:
Michael R Sweet
parent
bb91fb4b13
commit
7fe093f3bd
3
Makefile
3
Makefile
@ -43,10 +43,13 @@ PUBOBJS = \
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pdfio-array.o \
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pdfio-common.o \
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pdfio-content.o \
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pdfio-crypto.o \
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pdfio-dict.o \
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pdfio-file.o \
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pdfio-md5.o \
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pdfio-object.o \
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pdfio-page.o \
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pdfio-rc4.o \
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pdfio-stream.o \
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pdfio-string.o \
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pdfio-token.o \
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512
pdfio-crypto.c
Normal file
512
pdfio-crypto.c
Normal file
@ -0,0 +1,512 @@
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//
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// Cryptographic functions for PDFio.
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//
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// Copyright © 2021 by Michael R Sweet.
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//
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// Licensed under Apache License v2.0. See the file "LICENSE" for more
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// information.
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//
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// AES code is adapted from the "tiny-AES-c" project
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// (<https://github.com/kokke/tiny-AES-c>)
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//
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//
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// Include necessary headers...
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//
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#include "pdfio-private.h"
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//
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// Local types...
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//
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typedef uint8_t state_t[4][4]; // 4x4 AES state table
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//
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// Local globals...
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//
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static const uint8_t sbox[256] = // S-box lookup table
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{
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//0 1 2 3 4 5 6 7 8 9 A B C D E F
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0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
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0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
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0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
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0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
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0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
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0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
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0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
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0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
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0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
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0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
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0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
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0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
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0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
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0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
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0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
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0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
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};
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static const uint8_t rsbox[256] = // Reverse S-box lookup table
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{
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0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
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0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
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0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
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0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
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0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
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0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
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0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
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0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
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0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
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0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
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0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
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0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
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0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
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0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
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0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
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0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d
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};
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// The round constant word array, Rcon[i], contains the values given by
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// x to the power (i-1) being powers of x (x is denoted as {02}) in the field GF(2^8)
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static const uint8_t Rcon[11] = // Round constants
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{
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0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36
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};
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//
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// Local functions...
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//
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static void AddRoundKey(uint8_t round, state_t *state, const uint8_t *RoundKey);
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static void SubBytes(state_t *state);
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static void ShiftRows(state_t *state);
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static uint8_t xtime(uint8_t x);
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static void MixColumns(state_t *state);
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static uint8_t Multiply(uint8_t x, uint8_t y);
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static void InvMixColumns(state_t *state);
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static void InvSubBytes(state_t *state);
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static void InvShiftRows(state_t *state);
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static void Cipher(state_t *state, const _pdfio_aes_t *ctx);
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static void InvCipher(state_t *state, const _pdfio_aes_t *ctx);
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static void XorWithIv(uint8_t *buf, const uint8_t *Iv);
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//
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// '_pdfioCryptoAESInit()' - Initialize an AES context.
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//
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void
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_pdfioCryptoAESInit(
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_pdfio_aes_t *ctx, // I - AES context
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const uint8_t *key, // I - Key
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size_t keylen, // I - Length of key (must be 16 or 32)
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const uint8_t *iv) // I - 16-byte initialization vector
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{
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size_t i; // Looping var
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uint8_t *rkptr0, // Previous round_key values
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*rkptr, // Current round_key values
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*rkend, // End of round_key values
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tempa[4]; // Used for the column/row operations
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size_t roundlen = keylen + 24; // Length of round_key
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size_t nwords = keylen / 4; // Number of 32-bit words in key
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// Clear context
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memset(ctx, 0, sizeof(_pdfio_aes_t));
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// The first round key is the key itself.
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memcpy(ctx->round_key, key, keylen);
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// All other round keys are found from the previous round keys.
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for (rkptr0 = ctx->round_key, rkptr = rkptr0 + keylen, rkend = rkptr + roundlen, i = nwords; rkptr < rkend; i ++)
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{
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if ((i % nwords) == 0)
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{
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// Shifts word left once - [a0,a1,a2,a3] becomes [a1,a2,a3,a0]
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tempa[0] = rkptr[-3];
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tempa[1] = rkptr[-2];
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tempa[2] = rkptr[-1];
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tempa[3] = rkptr[-4];
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// Apply the S-box to each of the four bytes to produce an output word.
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tempa[0] = sbox[tempa[0]];
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tempa[1] = sbox[tempa[1]];
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tempa[2] = sbox[tempa[2]];
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tempa[3] = sbox[tempa[3]];
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tempa[0] = tempa[0] ^ Rcon[i / nwords];
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}
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else if (keylen == 32 && (i % nwords) == 4)
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{
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// Apply the S-box to each of the four bytes to produce an output word.
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tempa[0] = sbox[rkptr[-4]];
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tempa[1] = sbox[rkptr[-3]];
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tempa[2] = sbox[rkptr[-2]];
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tempa[3] = sbox[rkptr[-1]];
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}
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else
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{
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tempa[0] = rkptr[-4];
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tempa[1] = rkptr[-3];
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tempa[2] = rkptr[-2];
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tempa[3] = rkptr[-1];
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}
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*rkptr++ = *rkptr0++ ^ tempa[0];
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*rkptr++ = *rkptr0++ ^ tempa[1];
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*rkptr++ = *rkptr0++ ^ tempa[2];
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*rkptr++ = *rkptr0++ ^ tempa[3];
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}
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// Copy the initialization vector...
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if (iv)
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memcpy(ctx->iv, iv, sizeof(ctx->iv));
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}
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//
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// '_pdfioCryptoAESDecrypt()' - Decrypt a block of bytes with AES.
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//
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void
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_pdfioCryptoAESDecrypt(
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_pdfio_aes_t *ctx, // I - AES context
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uint8_t *buffer, // I - Buffer
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size_t len) // I - Number of bytes to decrypt
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{
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uint8_t next_iv[16]; // Next IV value
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while (len > 15)
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{
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memcpy(next_iv, buffer, 16);
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InvCipher((state_t *)buffer, ctx);
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XorWithIv(buffer, ctx->iv);
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memcpy(ctx->iv, next_iv, 16);
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buffer += 16;
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len -= 16;
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}
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if (len > 0)
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{
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// Pad the final buffer with (16 - len)...
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uint8_t temp[16]; // Temporary buffer
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memset(temp, 16 - len, sizeof(temp));
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memcpy(temp, buffer, len);
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memcpy(next_iv, temp, 16);
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InvCipher((state_t *)temp, ctx);
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XorWithIv(temp, ctx->iv);
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memcpy(ctx->iv, next_iv, 16);
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memcpy(buffer, temp, len);
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}
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}
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//
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// '_pdfioCryptoAESEncrypt()' - Encrypt a block of bytes with AES.
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//
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void
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_pdfioCryptoAESEncrypt(
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_pdfio_aes_t *ctx, // I - AES context
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uint8_t *buffer, // I - Buffer
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size_t len) // I - Number of bytes to decrypt
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{
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uint8_t *iv = ctx->iv; // Current IV for CBC
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uint8_t temp[16]; // Temporary buffer
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while (len > 15)
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{
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XorWithIv(buffer, iv);
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Cipher((state_t*)buffer, ctx);
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iv = buffer;
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buffer += 16;
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len -= 16;
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}
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if (len > 0)
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{
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// Pad the final buffer with (16 - len)...
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memset(temp, 16 - len, sizeof(temp));
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memcpy(temp, buffer, len);
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XorWithIv(temp, iv);
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Cipher((state_t*)temp, ctx);
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iv = temp;
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memcpy(buffer, temp, len);
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}
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/* store Iv in ctx for next call */
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memcpy(ctx->iv, iv, 16);
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}
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// This function adds the round key to state.
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// The round key is added to the state by an XOR function.
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static void
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AddRoundKey(uint8_t round, state_t *state, const uint8_t *RoundKey)
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{
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unsigned i; // Looping var
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uint8_t *sptr = (*state)[0]; // Pointer into state
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for (RoundKey += round * 16, i = 16; i > 0; i --, sptr ++, RoundKey ++)
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*sptr ^= *RoundKey;
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}
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// The SubBytes Function Substitutes the values in the
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// state matrix with values in an S-box.
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static void
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SubBytes(state_t *state)
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{
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unsigned i; // Looping var
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uint8_t *sptr = (*state)[0]; // Pointer into state
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for (i = 16; i > 0; i --, sptr ++)
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*sptr = sbox[*sptr];
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}
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// The ShiftRows() function shifts the rows in the state to the left.
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// Each row is shifted with different offset.
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// Offset = Row number. So the first row is not shifted.
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static void
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ShiftRows(state_t *state)
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{
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uint8_t *sptr = (*state)[0]; // Pointer into state
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uint8_t temp; // Temporary value
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// Rotate first row 1 columns to left
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temp = sptr[1];
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sptr[1] = sptr[5];
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sptr[5] = sptr[9];
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sptr[9] = sptr[13];
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sptr[13] = temp;
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// Rotate second row 2 columns to left
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temp = sptr[2];
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sptr[2] = sptr[10];
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sptr[10] = temp;
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temp = sptr[6];
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sptr[6] = sptr[14];
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sptr[14] = temp;
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// Rotate third row 3 columns to left
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temp = sptr[3];
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sptr[3] = sptr[15];
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sptr[15] = sptr[11];
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sptr[11] = sptr[7];
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sptr[7] = temp;
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}
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static uint8_t
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xtime(uint8_t x)
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{
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return ((x << 1) ^ ((x >> 7) * 0x1b));
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}
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// MixColumns function mixes the columns of the state matrix
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static void
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MixColumns(state_t *state)
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{
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unsigned i; // Looping var
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uint8_t *sptr = (*state)[0]; // Pointer into state
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uint8_t Tmp, Tm, t; // Temporary values
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for (i = 4; i > 0; i --, sptr += 4)
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{
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t = sptr[0];
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Tmp = sptr[0] ^ sptr[1] ^ sptr[2] ^ sptr[3];
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Tm = sptr[0] ^ sptr[1];
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Tm = xtime(Tm);
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sptr[0] ^= Tm ^ Tmp;
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Tm = sptr[1] ^ sptr[2];
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Tm = xtime(Tm);
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sptr[1] ^= Tm ^ Tmp;
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Tm = sptr[2] ^ sptr[3];
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Tm = xtime(Tm);
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sptr[2] ^= Tm ^ Tmp;
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Tm = sptr[3] ^ t;
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Tm = xtime(Tm);
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sptr[3] ^= Tm ^ Tmp;
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}
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}
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// Multiply is used to multiply numbers in the field GF(2^8)
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// Note: The last call to xtime() is unneeded, but often ends up generating a smaller binary
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// The compiler seems to be able to vectorize the operation better this way.
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// See https://github.com/kokke/tiny-AES-c/pull/34
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static uint8_t Multiply(uint8_t x, uint8_t y)
|
||||
{
|
||||
return (((y & 1) * x) ^
|
||||
((y>>1 & 1) * xtime(x)) ^
|
||||
((y>>2 & 1) * xtime(xtime(x))) ^
|
||||
((y>>3 & 1) * xtime(xtime(xtime(x)))) ^
|
||||
((y>>4 & 1) * xtime(xtime(xtime(xtime(x)))))); /* this last call to xtime() can be omitted */
|
||||
}
|
||||
|
||||
|
||||
// MixColumns function mixes the columns of the state matrix.
|
||||
// The method used to multiply may be difficult to understand for the inexperienced.
|
||||
// Please use the references to gain more information.
|
||||
static void
|
||||
InvMixColumns(state_t *state)
|
||||
{
|
||||
unsigned i; // Looping var
|
||||
uint8_t *sptr = (*state)[0]; // Pointer into state
|
||||
uint8_t a, b, c, d; // Temporary values
|
||||
|
||||
|
||||
for (i = 4; i > 0; i --)
|
||||
{
|
||||
a = sptr[0];
|
||||
b = sptr[1];
|
||||
c = sptr[2];
|
||||
d = sptr[3];
|
||||
|
||||
*sptr++ = Multiply(a, 0x0e) ^ Multiply(b, 0x0b) ^ Multiply(c, 0x0d) ^ Multiply(d, 0x09);
|
||||
*sptr++ = Multiply(a, 0x09) ^ Multiply(b, 0x0e) ^ Multiply(c, 0x0b) ^ Multiply(d, 0x0d);
|
||||
*sptr++ = Multiply(a, 0x0d) ^ Multiply(b, 0x09) ^ Multiply(c, 0x0e) ^ Multiply(d, 0x0b);
|
||||
*sptr++ = Multiply(a, 0x0b) ^ Multiply(b, 0x0d) ^ Multiply(c, 0x09) ^ Multiply(d, 0x0e);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
// The SubBytes Function Substitutes the values in the
|
||||
// state matrix with values in an S-box.
|
||||
static void
|
||||
InvSubBytes(state_t *state)
|
||||
{
|
||||
unsigned i; // Looping var
|
||||
uint8_t *sptr = (*state)[0]; // Pointer into state
|
||||
|
||||
|
||||
for (i = 16; i > 0; i --, sptr ++)
|
||||
*sptr = rsbox[*sptr];
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
InvShiftRows(state_t *state)
|
||||
{
|
||||
uint8_t *sptr = (*state)[0]; // Pointer into state
|
||||
uint8_t temp; // Temporary value
|
||||
|
||||
|
||||
// Rotate first row 1 columns to right
|
||||
temp = sptr[13];
|
||||
sptr[13] = sptr[9];
|
||||
sptr[9] = sptr[5];
|
||||
sptr[5] = sptr[1];
|
||||
sptr[1] = temp;
|
||||
|
||||
// Rotate second row 2 columns to right
|
||||
temp = sptr[2];
|
||||
sptr[2] = sptr[10];
|
||||
sptr[10] = temp;
|
||||
|
||||
temp = sptr[6];
|
||||
sptr[6] = sptr[14];
|
||||
sptr[14] = temp;
|
||||
|
||||
// Rotate third row 3 columns to right
|
||||
temp = sptr[3];
|
||||
sptr[3] = sptr[7];
|
||||
sptr[7] = sptr[11];
|
||||
sptr[11] = sptr[15];
|
||||
sptr[15] = temp;
|
||||
}
|
||||
|
||||
|
||||
// Cipher is the main function that encrypts the PlainText.
|
||||
static void
|
||||
Cipher(state_t *state, const _pdfio_aes_t *ctx)
|
||||
{
|
||||
uint8_t round = 0;
|
||||
|
||||
// Add the First round key to the state before starting the rounds.
|
||||
AddRoundKey(0, state, ctx->round_key);
|
||||
|
||||
// There will be Nr rounds.
|
||||
// The first Nr-1 rounds are identical.
|
||||
// These Nr rounds are executed in the loop below.
|
||||
// Last one without MixColumns()
|
||||
for (round = 1; ; ++round)
|
||||
{
|
||||
SubBytes(state);
|
||||
ShiftRows(state);
|
||||
if (round == ctx->round_size)
|
||||
break;
|
||||
|
||||
MixColumns(state);
|
||||
AddRoundKey(round, state, ctx->round_key);
|
||||
}
|
||||
// Add round key to last round
|
||||
AddRoundKey(ctx->round_size, state, ctx->round_key);
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
InvCipher(state_t *state, const _pdfio_aes_t *ctx)
|
||||
{
|
||||
uint8_t round = 0;
|
||||
|
||||
// Add the First round key to the state before starting the rounds.
|
||||
AddRoundKey(ctx->round_size, state, ctx->round_key);
|
||||
|
||||
// There will be Nr rounds.
|
||||
// The first Nr-1 rounds are identical.
|
||||
// These Nr rounds are executed in the loop below.
|
||||
// Last one without InvMixColumn()
|
||||
for (round = ctx->round_size - 1; ; round --)
|
||||
{
|
||||
InvShiftRows(state);
|
||||
InvSubBytes(state);
|
||||
AddRoundKey(round, state, ctx->round_key);
|
||||
|
||||
if (round == 0)
|
||||
break;
|
||||
|
||||
InvMixColumns(state);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
XorWithIv(uint8_t *buf, const uint8_t *Iv)
|
||||
{
|
||||
// 16-byte block...
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
*buf++ ^= *Iv++;
|
||||
}
|
||||
338
pdfio-md5.c
Normal file
338
pdfio-md5.c
Normal file
@ -0,0 +1,338 @@
|
||||
//
|
||||
// MD5 functions for PDFio.
|
||||
//
|
||||
// Copyright © 2021 by Michael R Sweet.
|
||||
// Copyright © 1999 Aladdin Enterprises. All rights reserved.
|
||||
//
|
||||
// This software is provided 'as-is', without any express or implied
|
||||
// warranty. In no event will the authors be held liable for any damages
|
||||
// arising from the use of this software.
|
||||
//
|
||||
// Permission is granted to anyone to use this software for any purpose,
|
||||
// including commercial applications, and to alter it and redistribute it
|
||||
// freely, subject to the following restrictions:
|
||||
//
|
||||
// 1. The origin of this software must not be misrepresented; you must not
|
||||
// claim that you wrote the original software. If you use this software
|
||||
// in a product, an acknowledgment in the product documentation would be
|
||||
// appreciated but is not required.
|
||||
// 2. Altered source versions must be plainly marked as such, and must not be
|
||||
// misrepresented as being the original software.
|
||||
// 3. This notice may not be removed or altered from any source distribution.
|
||||
//
|
||||
// L. Peter Deutsch
|
||||
// ghost@aladdin.com
|
||||
//
|
||||
|
||||
#include "pdfio-private.h"
|
||||
|
||||
|
||||
/*
|
||||
Independent implementation of MD5 (RFC 1321).
|
||||
|
||||
This code implements the MD5 Algorithm defined in RFC 1321.
|
||||
It is derived directly from the text of the RFC and not from the
|
||||
reference implementation.
|
||||
|
||||
The original and principal author of md5.c is L. Peter Deutsch
|
||||
<ghost@aladdin.com>. Other authors are noted in the change history
|
||||
that follows (in reverse chronological order):
|
||||
|
||||
1999-11-04 lpd Edited comments slightly for automatic TOC extraction.
|
||||
1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5).
|
||||
1999-05-03 lpd Original version.
|
||||
*/
|
||||
|
||||
#define T1 0xd76aa478
|
||||
#define T2 0xe8c7b756
|
||||
#define T3 0x242070db
|
||||
#define T4 0xc1bdceee
|
||||
#define T5 0xf57c0faf
|
||||
#define T6 0x4787c62a
|
||||
#define T7 0xa8304613
|
||||
#define T8 0xfd469501
|
||||
#define T9 0x698098d8
|
||||
#define T10 0x8b44f7af
|
||||
#define T11 0xffff5bb1
|
||||
#define T12 0x895cd7be
|
||||
#define T13 0x6b901122
|
||||
#define T14 0xfd987193
|
||||
#define T15 0xa679438e
|
||||
#define T16 0x49b40821
|
||||
#define T17 0xf61e2562
|
||||
#define T18 0xc040b340
|
||||
#define T19 0x265e5a51
|
||||
#define T20 0xe9b6c7aa
|
||||
#define T21 0xd62f105d
|
||||
#define T22 0x02441453
|
||||
#define T23 0xd8a1e681
|
||||
#define T24 0xe7d3fbc8
|
||||
#define T25 0x21e1cde6
|
||||
#define T26 0xc33707d6
|
||||
#define T27 0xf4d50d87
|
||||
#define T28 0x455a14ed
|
||||
#define T29 0xa9e3e905
|
||||
#define T30 0xfcefa3f8
|
||||
#define T31 0x676f02d9
|
||||
#define T32 0x8d2a4c8a
|
||||
#define T33 0xfffa3942
|
||||
#define T34 0x8771f681
|
||||
#define T35 0x6d9d6122
|
||||
#define T36 0xfde5380c
|
||||
#define T37 0xa4beea44
|
||||
#define T38 0x4bdecfa9
|
||||
#define T39 0xf6bb4b60
|
||||
#define T40 0xbebfbc70
|
||||
#define T41 0x289b7ec6
|
||||
#define T42 0xeaa127fa
|
||||
#define T43 0xd4ef3085
|
||||
#define T44 0x04881d05
|
||||
#define T45 0xd9d4d039
|
||||
#define T46 0xe6db99e5
|
||||
#define T47 0x1fa27cf8
|
||||
#define T48 0xc4ac5665
|
||||
#define T49 0xf4292244
|
||||
#define T50 0x432aff97
|
||||
#define T51 0xab9423a7
|
||||
#define T52 0xfc93a039
|
||||
#define T53 0x655b59c3
|
||||
#define T54 0x8f0ccc92
|
||||
#define T55 0xffeff47d
|
||||
#define T56 0x85845dd1
|
||||
#define T57 0x6fa87e4f
|
||||
#define T58 0xfe2ce6e0
|
||||
#define T59 0xa3014314
|
||||
#define T60 0x4e0811a1
|
||||
#define T61 0xf7537e82
|
||||
#define T62 0xbd3af235
|
||||
#define T63 0x2ad7d2bb
|
||||
#define T64 0xeb86d391
|
||||
|
||||
static void
|
||||
md5_process(_pdfio_md5_t *pms, const uint8_t *data /*[64]*/)
|
||||
{
|
||||
uint32_t
|
||||
a = pms->abcd[0], b = pms->abcd[1],
|
||||
c = pms->abcd[2], d = pms->abcd[3];
|
||||
uint32_t t;
|
||||
|
||||
#ifndef ARCH_IS_BIG_ENDIAN
|
||||
# define ARCH_IS_BIG_ENDIAN 1 /* slower, default implementation */
|
||||
#endif
|
||||
#if ARCH_IS_BIG_ENDIAN
|
||||
|
||||
/*
|
||||
* On big-endian machines, we must arrange the bytes in the right
|
||||
* order. (This also works on machines of unknown byte order.)
|
||||
*/
|
||||
uint32_t X[16];
|
||||
const uint8_t *xp = data;
|
||||
int i;
|
||||
|
||||
for (i = 0; i < 16; ++i, xp += 4)
|
||||
X[i] = xp[0] + (unsigned)(xp[1] << 8) + (unsigned)(xp[2] << 16) + (unsigned)(xp[3] << 24);
|
||||
|
||||
#else /* !ARCH_IS_BIG_ENDIAN */
|
||||
|
||||
/*
|
||||
* On little-endian machines, we can process properly aligned data
|
||||
* without copying it.
|
||||
*/
|
||||
uint32_t xbuf[16];
|
||||
const uint32_t *X;
|
||||
|
||||
if (!((data - (const uint8_t *)0) & 3)) {
|
||||
/* data are properly aligned */
|
||||
X = (const uint32_t *)data;
|
||||
} else {
|
||||
/* not aligned */
|
||||
memcpy(xbuf, data, 64);
|
||||
X = xbuf;
|
||||
}
|
||||
#endif
|
||||
|
||||
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
|
||||
|
||||
/* Round 1. */
|
||||
/* Let [abcd k s i] denote the operation
|
||||
a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */
|
||||
#define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
|
||||
#define SET(a, b, c, d, k, s, Ti)\
|
||||
t = a + F(b,c,d) + X[k] + Ti;\
|
||||
a = ROTATE_LEFT(t, s) + b
|
||||
/* Do the following 16 operations. */
|
||||
SET(a, b, c, d, 0, 7, T1);
|
||||
SET(d, a, b, c, 1, 12, T2);
|
||||
SET(c, d, a, b, 2, 17, T3);
|
||||
SET(b, c, d, a, 3, 22, T4);
|
||||
SET(a, b, c, d, 4, 7, T5);
|
||||
SET(d, a, b, c, 5, 12, T6);
|
||||
SET(c, d, a, b, 6, 17, T7);
|
||||
SET(b, c, d, a, 7, 22, T8);
|
||||
SET(a, b, c, d, 8, 7, T9);
|
||||
SET(d, a, b, c, 9, 12, T10);
|
||||
SET(c, d, a, b, 10, 17, T11);
|
||||
SET(b, c, d, a, 11, 22, T12);
|
||||
SET(a, b, c, d, 12, 7, T13);
|
||||
SET(d, a, b, c, 13, 12, T14);
|
||||
SET(c, d, a, b, 14, 17, T15);
|
||||
SET(b, c, d, a, 15, 22, T16);
|
||||
#undef SET
|
||||
|
||||
/* Round 2. */
|
||||
/* Let [abcd k s i] denote the operation
|
||||
a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s). */
|
||||
#define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
|
||||
#define SET(a, b, c, d, k, s, Ti)\
|
||||
t = a + G(b,c,d) + X[k] + Ti;\
|
||||
a = ROTATE_LEFT(t, s) + b
|
||||
/* Do the following 16 operations. */
|
||||
SET(a, b, c, d, 1, 5, T17);
|
||||
SET(d, a, b, c, 6, 9, T18);
|
||||
SET(c, d, a, b, 11, 14, T19);
|
||||
SET(b, c, d, a, 0, 20, T20);
|
||||
SET(a, b, c, d, 5, 5, T21);
|
||||
SET(d, a, b, c, 10, 9, T22);
|
||||
SET(c, d, a, b, 15, 14, T23);
|
||||
SET(b, c, d, a, 4, 20, T24);
|
||||
SET(a, b, c, d, 9, 5, T25);
|
||||
SET(d, a, b, c, 14, 9, T26);
|
||||
SET(c, d, a, b, 3, 14, T27);
|
||||
SET(b, c, d, a, 8, 20, T28);
|
||||
SET(a, b, c, d, 13, 5, T29);
|
||||
SET(d, a, b, c, 2, 9, T30);
|
||||
SET(c, d, a, b, 7, 14, T31);
|
||||
SET(b, c, d, a, 12, 20, T32);
|
||||
#undef SET
|
||||
|
||||
/* Round 3. */
|
||||
/* Let [abcd k s t] denote the operation
|
||||
a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s). */
|
||||
#define H(x, y, z) ((x) ^ (y) ^ (z))
|
||||
#define SET(a, b, c, d, k, s, Ti)\
|
||||
t = a + H(b,c,d) + X[k] + Ti;\
|
||||
a = ROTATE_LEFT(t, s) + b
|
||||
/* Do the following 16 operations. */
|
||||
SET(a, b, c, d, 5, 4, T33);
|
||||
SET(d, a, b, c, 8, 11, T34);
|
||||
SET(c, d, a, b, 11, 16, T35);
|
||||
SET(b, c, d, a, 14, 23, T36);
|
||||
SET(a, b, c, d, 1, 4, T37);
|
||||
SET(d, a, b, c, 4, 11, T38);
|
||||
SET(c, d, a, b, 7, 16, T39);
|
||||
SET(b, c, d, a, 10, 23, T40);
|
||||
SET(a, b, c, d, 13, 4, T41);
|
||||
SET(d, a, b, c, 0, 11, T42);
|
||||
SET(c, d, a, b, 3, 16, T43);
|
||||
SET(b, c, d, a, 6, 23, T44);
|
||||
SET(a, b, c, d, 9, 4, T45);
|
||||
SET(d, a, b, c, 12, 11, T46);
|
||||
SET(c, d, a, b, 15, 16, T47);
|
||||
SET(b, c, d, a, 2, 23, T48);
|
||||
#undef SET
|
||||
|
||||
/* Round 4. */
|
||||
/* Let [abcd k s t] denote the operation
|
||||
a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s). */
|
||||
#define I(x, y, z) ((y) ^ ((x) | ~(z)))
|
||||
#define SET(a, b, c, d, k, s, Ti)\
|
||||
t = a + I(b,c,d) + X[k] + Ti;\
|
||||
a = ROTATE_LEFT(t, s) + b
|
||||
/* Do the following 16 operations. */
|
||||
SET(a, b, c, d, 0, 6, T49);
|
||||
SET(d, a, b, c, 7, 10, T50);
|
||||
SET(c, d, a, b, 14, 15, T51);
|
||||
SET(b, c, d, a, 5, 21, T52);
|
||||
SET(a, b, c, d, 12, 6, T53);
|
||||
SET(d, a, b, c, 3, 10, T54);
|
||||
SET(c, d, a, b, 10, 15, T55);
|
||||
SET(b, c, d, a, 1, 21, T56);
|
||||
SET(a, b, c, d, 8, 6, T57);
|
||||
SET(d, a, b, c, 15, 10, T58);
|
||||
SET(c, d, a, b, 6, 15, T59);
|
||||
SET(b, c, d, a, 13, 21, T60);
|
||||
SET(a, b, c, d, 4, 6, T61);
|
||||
SET(d, a, b, c, 11, 10, T62);
|
||||
SET(c, d, a, b, 2, 15, T63);
|
||||
SET(b, c, d, a, 9, 21, T64);
|
||||
#undef SET
|
||||
|
||||
/* Then perform the following additions. (That is increment each
|
||||
of the four registers by the value it had before this block
|
||||
was started.) */
|
||||
pms->abcd[0] += a;
|
||||
pms->abcd[1] += b;
|
||||
pms->abcd[2] += c;
|
||||
pms->abcd[3] += d;
|
||||
}
|
||||
|
||||
void
|
||||
_pdfioCryptoMD5Init(_pdfio_md5_t *pms)
|
||||
{
|
||||
pms->count[0] = pms->count[1] = 0;
|
||||
pms->abcd[0] = 0x67452301;
|
||||
pms->abcd[1] = 0xefcdab89;
|
||||
pms->abcd[2] = 0x98badcfe;
|
||||
pms->abcd[3] = 0x10325476;
|
||||
}
|
||||
|
||||
void
|
||||
_pdfioCryptoMD5Append(_pdfio_md5_t *pms, const uint8_t *data, size_t nbytes)
|
||||
{
|
||||
const uint8_t *p = data;
|
||||
size_t left = nbytes;
|
||||
int offset = (pms->count[0] >> 3) & 63;
|
||||
uint32_t nbits = (uint32_t)(nbytes << 3);
|
||||
|
||||
if (nbytes == 0)
|
||||
return;
|
||||
|
||||
/* Update the message length. */
|
||||
pms->count[1] += (unsigned)(nbytes >> 29);
|
||||
pms->count[0] += nbits;
|
||||
if (pms->count[0] < nbits)
|
||||
pms->count[1]++;
|
||||
|
||||
/* Process an initial partial block. */
|
||||
if (offset) {
|
||||
int copy = (offset + nbytes > 64 ? 64 - offset : nbytes);
|
||||
|
||||
memcpy(pms->buf + offset, p, copy);
|
||||
if (offset + copy < 64)
|
||||
return;
|
||||
p += copy;
|
||||
left -= copy;
|
||||
md5_process(pms, pms->buf);
|
||||
}
|
||||
|
||||
/* Process full blocks. */
|
||||
for (; left >= 64; p += 64, left -= 64)
|
||||
md5_process(pms, p);
|
||||
|
||||
/* Process a final partial block. */
|
||||
if (left)
|
||||
memcpy(pms->buf, p, left);
|
||||
}
|
||||
|
||||
void
|
||||
_pdfioCryptoMD5Finish(_pdfio_md5_t *pms, uint8_t digest[16])
|
||||
{
|
||||
static const uint8_t pad[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
|
||||
};
|
||||
uint8_t data[8];
|
||||
int i;
|
||||
|
||||
/* Save the length before padding. */
|
||||
for (i = 0; i < 8; ++i)
|
||||
data[i] = (uint8_t)(pms->count[i >> 2] >> ((i & 3) << 3));
|
||||
/* Pad to 56 bytes mod 64. */
|
||||
_pdfioCryptoMD5Append(pms, pad, ((55 - (pms->count[0] >> 3)) & 63) + 1);
|
||||
/* Append the length. */
|
||||
_pdfioCryptoMD5Append(pms, data, 8);
|
||||
for (i = 0; i < 16; ++i)
|
||||
digest[i] = (uint8_t)(pms->abcd[i >> 2] >> ((i & 3) << 3));
|
||||
}
|
||||
@ -24,6 +24,7 @@
|
||||
|
||||
# include "pdfio.h"
|
||||
# include <stdarg.h>
|
||||
# include <stdint.h>
|
||||
# include <string.h>
|
||||
# include <errno.h>
|
||||
# include <inttypes.h>
|
||||
@ -174,6 +175,28 @@ typedef struct _pdfio_value_s // Value structure
|
||||
} value; // Value union
|
||||
} _pdfio_value_t;
|
||||
|
||||
|
||||
typedef struct _pdfio_aes_s // AES encryption state
|
||||
{
|
||||
size_t round_size; // Size of round key
|
||||
uint8_t round_key[240], // Round key
|
||||
iv[16]; // Initialization vector
|
||||
} _pdfio_aes_t;
|
||||
|
||||
typedef struct _pdfio_md5_s // MD5 hash state
|
||||
{
|
||||
uint32_t count[2]; // Message length in bits, lsw first
|
||||
uint32_t abcd[4]; // Digest buffer
|
||||
uint8_t buf[64]; // Accumulate block
|
||||
} _pdfio_md5_t;
|
||||
|
||||
typedef struct _pdfio_rc4_s // RC4 encryption state
|
||||
{
|
||||
uint8_t sbox[256]; // S boxes for encryption
|
||||
uint8_t i, j; // Current indices into S boxes
|
||||
} _pdfio_rc4_t;
|
||||
|
||||
|
||||
struct _pdfio_array_s
|
||||
{
|
||||
pdfio_file_t *pdf; // PDF file
|
||||
@ -294,6 +317,15 @@ extern _pdfio_value_t *_pdfioArrayGetValue(pdfio_array_t *a, size_t n) _PDFIO_IN
|
||||
extern pdfio_array_t *_pdfioArrayRead(pdfio_file_t *pdf, _pdfio_token_t *ts) _PDFIO_INTERNAL;
|
||||
extern bool _pdfioArrayWrite(pdfio_array_t *a) _PDFIO_INTERNAL;
|
||||
|
||||
extern void _pdfioCryptoAESInit(_pdfio_aes_t *ctx, const uint8_t *key, size_t keylen, const uint8_t *iv) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoAESDecrypt(_pdfio_aes_t *ctx, uint8_t *buffer, size_t len) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoAESEncrypt(_pdfio_aes_t *ctx, uint8_t *buffer, size_t len) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoMD5Append(_pdfio_md5_t *pms, const uint8_t *data, size_t nbytes) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoMD5Finish(_pdfio_md5_t *pms, uint8_t digest[16]) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoMD5Init(_pdfio_md5_t *pms) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoRC4Init(_pdfio_rc4_t *ctx, const uint8_t *key, size_t keylen) _PDFIO_INTERNAL;
|
||||
extern void _pdfioCryptoRC4Crypt(_pdfio_rc4_t *ctx, uint8_t *buffer, size_t len) _PDFIO_INTERNAL;
|
||||
|
||||
extern void _pdfioDictDebug(pdfio_dict_t *dict, FILE *fp) _PDFIO_INTERNAL;
|
||||
extern void _pdfioDictDelete(pdfio_dict_t *dict) _PDFIO_INTERNAL;
|
||||
extern _pdfio_value_t *_pdfioDictGetValue(pdfio_dict_t *dict, const char *key) _PDFIO_INTERNAL;
|
||||
|
||||
107
pdfio-rc4.c
Normal file
107
pdfio-rc4.c
Normal file
@ -0,0 +1,107 @@
|
||||
//
|
||||
// RC4 functions for PDFio.
|
||||
//
|
||||
// Copyright © 2021 by Michael R Sweet.
|
||||
//
|
||||
// Original code by Tim Martin
|
||||
// Copyright © 1999 by Carnegie Mellon University, All Rights Reserved
|
||||
//
|
||||
// Permission to use, copy, modify, and distribute this software and its
|
||||
// documentation for any purpose and without fee is hereby granted,
|
||||
// provided that the above copyright notice appear in all copies and that
|
||||
// both that copyright notice and this permission notice appear in
|
||||
// supporting documentation, and that the name of Carnegie Mellon
|
||||
// University not be used in advertising or publicity pertaining to
|
||||
// distribution of the software without specific, written prior
|
||||
// permission.
|
||||
//
|
||||
// CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
|
||||
// THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
||||
// FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE FOR
|
||||
// ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
||||
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
||||
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
|
||||
// OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
||||
//
|
||||
|
||||
#include "pdfio-private.h"
|
||||
|
||||
|
||||
//
|
||||
// '_pdfioCryptoRC4Init()' - Initialize an RC4 context with the specified key.
|
||||
//
|
||||
|
||||
void
|
||||
_pdfioCryptoRC4Init(
|
||||
_pdfio_rc4_t *ctx, // IO - Context
|
||||
const uint8_t *key, // I - Key
|
||||
size_t keylen) // I - Length of key
|
||||
{
|
||||
size_t i; // Looping var
|
||||
uint8_t j, // S box counter
|
||||
tmp; // Temporary variable
|
||||
|
||||
|
||||
// Fill in linearly s0=0, s1=1, ...
|
||||
for (i = 0; i < 256; i ++)
|
||||
ctx->sbox[i] = (uint8_t)i;
|
||||
|
||||
for (i = 0, j = 0; i < 256; i ++)
|
||||
{
|
||||
// j = (j + Si + Ki) mod 256
|
||||
j += ctx->sbox[i] + key[i % keylen];
|
||||
|
||||
// Swap Si and Sj...
|
||||
tmp = ctx->sbox[i];
|
||||
ctx->sbox[i] = ctx->sbox[j];
|
||||
ctx->sbox[j] = tmp;
|
||||
}
|
||||
|
||||
// Initialize counters to 0 and return...
|
||||
ctx->i = 0;
|
||||
ctx->j = 0;
|
||||
}
|
||||
|
||||
|
||||
//
|
||||
// '_pdfioCryptoRC4Crypt()' - De/encrypt the given buffer.
|
||||
//
|
||||
|
||||
void
|
||||
_pdfioCryptoRC4Crypt(
|
||||
_pdfio_rc4_t *ctx, // I - Context
|
||||
uint8_t *buffer, // I - Buffer
|
||||
size_t len) // I - Size of buffers
|
||||
{
|
||||
uint8_t tmp, // Swap variable
|
||||
i, j, // Looping vars
|
||||
t; // Current S box
|
||||
|
||||
|
||||
// Loop through the entire buffer...
|
||||
i = ctx->i;
|
||||
j = ctx->j;
|
||||
|
||||
while (len > 0)
|
||||
{
|
||||
// Get the next S box indices...
|
||||
i ++;
|
||||
j += ctx->sbox[i];
|
||||
|
||||
// Swap Si and Sj...
|
||||
tmp = ctx->sbox[i];
|
||||
ctx->sbox[i] = ctx->sbox[j];
|
||||
ctx->sbox[j] = tmp;
|
||||
|
||||
// Get the S box index for this byte...
|
||||
t = ctx->sbox[i] + ctx->sbox[j];
|
||||
|
||||
// Encrypt using the S box...
|
||||
*buffer++ ^= ctx->sbox[t];
|
||||
len --;
|
||||
}
|
||||
|
||||
// Copy current S box indices back to context...
|
||||
ctx->i = i;
|
||||
ctx->j = j;
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user