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Diffstat (limited to 'src/3rdparty/des/des.cpp')
| -rw-r--r-- | src/3rdparty/des/des.cpp | 602 |
1 files changed, 602 insertions, 0 deletions
diff --git a/src/3rdparty/des/des.cpp b/src/3rdparty/des/des.cpp new file mode 100644 index 0000000000..c1a260bbac --- /dev/null +++ b/src/3rdparty/des/des.cpp @@ -0,0 +1,602 @@ +/* + * Implementation of DES encryption for NTLM + * + * Copyright 1997-2005 Simon Tatham. + * + * This software is released under the MIT license. + */ + +/* + * Description of DES + * ------------------ + * + * Unlike the description in FIPS 46, I'm going to use _sensible_ indices: + * bits in an n-bit word are numbered from 0 at the LSB to n-1 at the MSB. + * And S-boxes are indexed by six consecutive bits, not by the outer two + * followed by the middle four. + * + * The DES encryption routine requires a 64-bit input, and a key schedule K + * containing 16 48-bit elements. + * + * First the input is permuted by the initial permutation IP. + * Then the input is split into 32-bit words L and R. (L is the MSW.) + * Next, 16 rounds. In each round: + * (L, R) <- (R, L xor f(R, K[i])) + * Then the pre-output words L and R are swapped. + * Then L and R are glued back together into a 64-bit word. (L is the MSW, + * again, but since we just swapped them, the MSW is the R that came out + * of the last round.) + * The 64-bit output block is permuted by the inverse of IP and returned. + * + * Decryption is identical except that the elements of K are used in the + * opposite order. (This wouldn't work if that word swap didn't happen.) + * + * The function f, used in each round, accepts a 32-bit word R and a + * 48-bit key block K. It produces a 32-bit output. + * + * First R is expanded to 48 bits using the bit-selection function E. + * The resulting 48-bit block is XORed with the key block K to produce + * a 48-bit block X. + * This block X is split into eight groups of 6 bits. Each group of 6 + * bits is then looked up in one of the eight S-boxes to convert + * it to 4 bits. These eight groups of 4 bits are glued back + * together to produce a 32-bit preoutput block. + * The preoutput block is permuted using the permutation P and returned. + * + * Key setup maps a 64-bit key word into a 16x48-bit key schedule. Although + * the approved input format for the key is a 64-bit word, eight of the + * bits are discarded, so the actual quantity of key used is 56 bits. + * + * First the input key is converted to two 28-bit words C and D using + * the bit-selection function PC1. + * Then 16 rounds of key setup occur. In each round, C and D are each + * rotated left by either 1 or 2 bits (depending on which round), and + * then converted into a key schedule element using the bit-selection + * function PC2. + * + * That's the actual algorithm. Now for the tedious details: all those + * painful permutations and lookup tables. + * + * IP is a 64-to-64 bit permutation. Its output contains the following + * bits of its input (listed in order MSB to LSB of output). + * + * 6 14 22 30 38 46 54 62 4 12 20 28 36 44 52 60 + * 2 10 18 26 34 42 50 58 0 8 16 24 32 40 48 56 + * 7 15 23 31 39 47 55 63 5 13 21 29 37 45 53 61 + * 3 11 19 27 35 43 51 59 1 9 17 25 33 41 49 57 + * + * E is a 32-to-48 bit selection function. Its output contains the following + * bits of its input (listed in order MSB to LSB of output). + * + * 0 31 30 29 28 27 28 27 26 25 24 23 24 23 22 21 20 19 20 19 18 17 16 15 + * 16 15 14 13 12 11 12 11 10 9 8 7 8 7 6 5 4 3 4 3 2 1 0 31 + * + * The S-boxes are arbitrary table-lookups each mapping a 6-bit input to a + * 4-bit output. In other words, each S-box is an array[64] of 4-bit numbers. + * The S-boxes are listed below. The first S-box listed is applied to the + * most significant six bits of the block X; the last one is applied to the + * least significant. + * + * 14 0 4 15 13 7 1 4 2 14 15 2 11 13 8 1 + * 3 10 10 6 6 12 12 11 5 9 9 5 0 3 7 8 + * 4 15 1 12 14 8 8 2 13 4 6 9 2 1 11 7 + * 15 5 12 11 9 3 7 14 3 10 10 0 5 6 0 13 + * + * 15 3 1 13 8 4 14 7 6 15 11 2 3 8 4 14 + * 9 12 7 0 2 1 13 10 12 6 0 9 5 11 10 5 + * 0 13 14 8 7 10 11 1 10 3 4 15 13 4 1 2 + * 5 11 8 6 12 7 6 12 9 0 3 5 2 14 15 9 + * + * 10 13 0 7 9 0 14 9 6 3 3 4 15 6 5 10 + * 1 2 13 8 12 5 7 14 11 12 4 11 2 15 8 1 + * 13 1 6 10 4 13 9 0 8 6 15 9 3 8 0 7 + * 11 4 1 15 2 14 12 3 5 11 10 5 14 2 7 12 + * + * 7 13 13 8 14 11 3 5 0 6 6 15 9 0 10 3 + * 1 4 2 7 8 2 5 12 11 1 12 10 4 14 15 9 + * 10 3 6 15 9 0 0 6 12 10 11 1 7 13 13 8 + * 15 9 1 4 3 5 14 11 5 12 2 7 8 2 4 14 + * + * 2 14 12 11 4 2 1 12 7 4 10 7 11 13 6 1 + * 8 5 5 0 3 15 15 10 13 3 0 9 14 8 9 6 + * 4 11 2 8 1 12 11 7 10 1 13 14 7 2 8 13 + * 15 6 9 15 12 0 5 9 6 10 3 4 0 5 14 3 + * + * 12 10 1 15 10 4 15 2 9 7 2 12 6 9 8 5 + * 0 6 13 1 3 13 4 14 14 0 7 11 5 3 11 8 + * 9 4 14 3 15 2 5 12 2 9 8 5 12 15 3 10 + * 7 11 0 14 4 1 10 7 1 6 13 0 11 8 6 13 + * + * 4 13 11 0 2 11 14 7 15 4 0 9 8 1 13 10 + * 3 14 12 3 9 5 7 12 5 2 10 15 6 8 1 6 + * 1 6 4 11 11 13 13 8 12 1 3 4 7 10 14 7 + * 10 9 15 5 6 0 8 15 0 14 5 2 9 3 2 12 + * + * 13 1 2 15 8 13 4 8 6 10 15 3 11 7 1 4 + * 10 12 9 5 3 6 14 11 5 0 0 14 12 9 7 2 + * 7 2 11 1 4 14 1 7 9 4 12 10 14 8 2 13 + * 0 15 6 12 10 9 13 0 15 3 3 5 5 6 8 11 + * + * P is a 32-to-32 bit permutation. Its output contains the following + * bits of its input (listed in order MSB to LSB of output). + * + * 16 25 12 11 3 20 4 15 31 17 9 6 27 14 1 22 + * 30 24 8 18 0 5 29 23 13 19 2 26 10 21 28 7 + * + * PC1 is a 64-to-56 bit selection function. Its output is in two words, + * C and D. The word C contains the following bits of its input (listed + * in order MSB to LSB of output). + * + * 7 15 23 31 39 47 55 63 6 14 22 30 38 46 + * 54 62 5 13 21 29 37 45 53 61 4 12 20 28 + * + * And the word D contains these bits. + * + * 1 9 17 25 33 41 49 57 2 10 18 26 34 42 + * 50 58 3 11 19 27 35 43 51 59 36 44 52 60 + * + * PC2 is a 56-to-48 bit selection function. Its input is in two words, + * C and D. These are treated as one 56-bit word (with C more significant, + * so that bits 55 to 28 of the word are bits 27 to 0 of C, and bits 27 to + * 0 of the word are bits 27 to 0 of D). The output contains the following + * bits of this 56-bit input word (listed in order MSB to LSB of output). + * + * 42 39 45 32 55 51 53 28 41 50 35 46 33 37 44 52 30 48 40 49 29 36 43 54 + * 15 4 25 19 9 1 26 16 5 11 23 8 12 7 17 0 22 3 10 14 6 20 27 24 + */ + +/* + * Implementation details + * ---------------------- + * + * If you look at the code in this module, you'll find it looks + * nothing _like_ the above algorithm. Here I explain the + * differences... + * + * Key setup has not been heavily optimised here. We are not + * concerned with key agility: we aren't codebreakers. We don't + * mind a little delay (and it really is a little one; it may be a + * factor of five or so slower than it could be but it's still not + * an appreciable length of time) while setting up. The only tweaks + * in the key setup are ones which change the format of the key + * schedule to speed up the actual encryption. I'll describe those + * below. + * + * The first and most obvious optimisation is the S-boxes. Since + * each S-box always targets the same four bits in the final 32-bit + * word, so the output from (for example) S-box 0 must always be + * shifted left 28 bits, we can store the already-shifted outputs + * in the lookup tables. This reduces lookup-and-shift to lookup, + * so the S-box step is now just a question of ORing together eight + * table lookups. + * + * The permutation P is just a bit order change; it's invariant + * with respect to OR, in that P(x)|P(y) = P(x|y). Therefore, we + * can apply P to every entry of the S-box tables and then we don't + * have to do it in the code of f(). This yields a set of tables + * which might be called SP-boxes. + * + * The bit-selection function E is our next target. Note that E is + * immediately followed by the operation of splitting into 6-bit + * chunks. Examining the 6-bit chunks coming out of E we notice + * they're all contiguous within the word (speaking cyclically - + * the end two wrap round); so we can extract those bit strings + * individually rather than explicitly running E. This would yield + * code such as + * + * y |= SPboxes[0][ (rotl(R, 5) ^ top6bitsofK) & 0x3F ]; + * t |= SPboxes[1][ (rotl(R,11) ^ next6bitsofK) & 0x3F ]; + * + * and so on; and the key schedule preparation would have to + * provide each 6-bit chunk separately. + * + * Really we'd like to XOR in the key schedule element before + * looking up bit strings in R. This we can't do, naively, because + * the 6-bit strings we want overlap. But look at the strings: + * + * 3322222222221111111111 + * bit 10987654321098765432109876543210 + * + * box0 XXXXX X + * box1 XXXXXX + * box2 XXXXXX + * box3 XXXXXX + * box4 XXXXXX + * box5 XXXXXX + * box6 XXXXXX + * box7 X XXXXX + * + * The bit strings we need to XOR in for boxes 0, 2, 4 and 6 don't + * overlap with each other. Neither do the ones for boxes 1, 3, 5 + * and 7. So we could provide the key schedule in the form of two + * words that we can separately XOR into R, and then every S-box + * index is available as a (cyclically) contiguous 6-bit substring + * of one or the other of the results. + * + * The comments in Eric Young's libdes implementation point out + * that two of these bit strings require a rotation (rather than a + * simple shift) to extract. It's unavoidable that at least _one_ + * must do; but we can actually run the whole inner algorithm (all + * 16 rounds) rotated one bit to the left, so that what the `real' + * DES description sees as L=0x80000001 we see as L=0x00000003. + * This requires rotating all our SP-box entries one bit to the + * left, and rotating each word of the key schedule elements one to + * the left, and rotating L and R one bit left just after IP and + * one bit right again just before FP. And in each round we convert + * a rotate into a shift, so we've saved a few per cent. + * + * That's about it for the inner loop; the SP-box tables as listed + * below are what I've described here (the original S value, + * shifted to its final place in the input to P, run through P, and + * then rotated one bit left). All that remains is to optimise the + * initial permutation IP. + * + * IP is not an arbitrary permutation. It has the nice property + * that if you take any bit number, write it in binary (6 bits), + * permute those 6 bits and invert some of them, you get the final + * position of that bit. Specifically, the bit whose initial + * position is given (in binary) as fedcba ends up in position + * AcbFED (where a capital letter denotes the inverse of a bit). + * + * We have the 64-bit data in two 32-bit words L and R, where bits + * in L are those with f=1 and bits in R are those with f=0. We + * note that we can do a simple transformation: suppose we exchange + * the bits with f=1,c=0 and the bits with f=0,c=1. This will cause + * the bit fedcba to be in position cedfba - we've `swapped' bits c + * and f in the position of each bit! + * + * Better still, this transformation is easy. In the example above, + * bits in L with c=0 are bits 0x0F0F0F0F, and those in R with c=1 + * are 0xF0F0F0F0. So we can do + * + * difference = ((R >> 4) ^ L) & 0x0F0F0F0F + * R ^= (difference << 4) + * L ^= difference + * + * to perform the swap. Let's denote this by bitswap(4,0x0F0F0F0F). + * Also, we can invert the bit at the top just by exchanging L and + * R. So in a few swaps and a few of these bit operations we can + * do: + * + * Initially the position of bit fedcba is fedcba + * Swap L with R to make it Fedcba + * Perform bitswap( 4,0x0F0F0F0F) to make it cedFba + * Perform bitswap(16,0x0000FFFF) to make it ecdFba + * Swap L with R to make it EcdFba + * Perform bitswap( 2,0x33333333) to make it bcdFEa + * Perform bitswap( 8,0x00FF00FF) to make it dcbFEa + * Swap L with R to make it DcbFEa + * Perform bitswap( 1,0x55555555) to make it acbFED + * Swap L with R to make it AcbFED + * + * (In the actual code the four swaps are implicit: R and L are + * simply used the other way round in the first, second and last + * bitswap operations.) + * + * The final permutation is just the inverse of IP, so it can be + * performed by a similar set of operations. + */ + +struct des_context { + quint32 k0246[16], k1357[16]; +}; + +#define rotl(x, c) ( (x << c) | (x >> (32-c)) ) +#define rotl28(x, c) ( ( (x << c) | (x >> (28-c)) ) & 0x0FFFFFFF) + +static quint32 bitsel(quint32 * input, const int *bitnums, int size) +{ + quint32 ret = 0; + while (size--) { + int bitpos = *bitnums++; + ret <<= 1; + if (bitpos >= 0) + ret |= 1 & (input[bitpos / 32] >> (bitpos % 32)); + } + return ret; +} + +static inline void des_key_setup(quint32 key_msw, quint32 key_lsw, + struct des_context *sched) +{ + /* Tables are modified to work with 56-bit key */ + static const int PC1_Cbits[] = { + 6, 13, 20, 27, 34, 41, 48, 55, 5, 12, 19, 26, 33, 40, + 47, 54, 4, 11, 18, 25, 32, 39, 46, 53, 3, 10, 17, 24 + }; + static const int PC1_Dbits[] = { + 0, 7, 14, 21, 28, 35, 42, 49, 1, 8, 15, 22, 29, 36, + 43, 50, 2, 9, 16, 23, 30, 37, 44, 51, 31, 38, 45, 52 + }; + /* + * The bit numbers in the two lists below don't correspond to + * the ones in the above description of PC2, because in the + * above description C and D are concatenated so `bit 28' means + * bit 0 of C. In this implementation we're using the standard + * `bitsel' function above and C is in the second word, so bit + * 0 of C is addressed by writing `32' here. + */ + static const int PC2_0246[] = { + 49, 36, 59, 55, -1, -1, 37, 41, 48, 56, 34, 52, -1, -1, 15, 4, + 25, 19, 9, 1, -1, -1, 12, 7, 17, 0, 22, 3, -1, -1, 46, 43 + }; + static const int PC2_1357[] = { + -1, -1, 57, 32, 45, 54, 39, 50, -1, -1, 44, 53, 33, 40, 47, 58, + -1, -1, 26, 16, 5, 11, 23, 8, -1, -1, 10, 14, 6, 20, 27, 24 + }; + static const int leftshifts[] = { + 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 + }; + + quint32 C, D; + quint32 buf[2]; + int i; + + buf[0] = key_lsw; + buf[1] = key_msw; + + C = bitsel(buf, PC1_Cbits, 28); + D = bitsel(buf, PC1_Dbits, 28); + + for (i = 0; i < 16; i++) { + C = rotl28(C, leftshifts[i]); + D = rotl28(D, leftshifts[i]); + buf[0] = D; + buf[1] = C; + sched->k0246[i] = bitsel(buf, PC2_0246, 32); + sched->k1357[i] = bitsel(buf, PC2_1357, 32); + } +} + +static const quint32 SPboxes[8][64] = { + {0x01010400, 0x00000000, 0x00010000, 0x01010404, + 0x01010004, 0x00010404, 0x00000004, 0x00010000, + 0x00000400, 0x01010400, 0x01010404, 0x00000400, + 0x01000404, 0x01010004, 0x01000000, 0x00000004, + 0x00000404, 0x01000400, 0x01000400, 0x00010400, + 0x00010400, 0x01010000, 0x01010000, 0x01000404, + 0x00010004, 0x01000004, 0x01000004, 0x00010004, + 0x00000000, 0x00000404, 0x00010404, 0x01000000, + 0x00010000, 0x01010404, 0x00000004, 0x01010000, + 0x01010400, 0x01000000, 0x01000000, 0x00000400, + 0x01010004, 0x00010000, 0x00010400, 0x01000004, + 0x00000400, 0x00000004, 0x01000404, 0x00010404, + 0x01010404, 0x00010004, 0x01010000, 0x01000404, + 0x01000004, 0x00000404, 0x00010404, 0x01010400, + 0x00000404, 0x01000400, 0x01000400, 0x00000000, + 0x00010004, 0x00010400, 0x00000000, 0x01010004}, + + {0x80108020, 0x80008000, 0x00008000, 0x00108020, + 0x00100000, 0x00000020, 0x80100020, 0x80008020, + 0x80000020, 0x80108020, 0x80108000, 0x80000000, + 0x80008000, 0x00100000, 0x00000020, 0x80100020, + 0x00108000, 0x00100020, 0x80008020, 0x00000000, + 0x80000000, 0x00008000, 0x00108020, 0x80100000, + 0x00100020, 0x80000020, 0x00000000, 0x00108000, + 0x00008020, 0x80108000, 0x80100000, 0x00008020, + 0x00000000, 0x00108020, 0x80100020, 0x00100000, + 0x80008020, 0x80100000, 0x80108000, 0x00008000, + 0x80100000, 0x80008000, 0x00000020, 0x80108020, + 0x00108020, 0x00000020, 0x00008000, 0x80000000, + 0x00008020, 0x80108000, 0x00100000, 0x80000020, + 0x00100020, 0x80008020, 0x80000020, 0x00100020, + 0x00108000, 0x00000000, 0x80008000, 0x00008020, + 0x80000000, 0x80100020, 0x80108020, 0x00108000}, + + {0x00000208, 0x08020200, 0x00000000, 0x08020008, + 0x08000200, 0x00000000, 0x00020208, 0x08000200, + 0x00020008, 0x08000008, 0x08000008, 0x00020000, + 0x08020208, 0x00020008, 0x08020000, 0x00000208, + 0x08000000, 0x00000008, 0x08020200, 0x00000200, + 0x00020200, 0x08020000, 0x08020008, 0x00020208, + 0x08000208, 0x00020200, 0x00020000, 0x08000208, + 0x00000008, 0x08020208, 0x00000200, 0x08000000, + 0x08020200, 0x08000000, 0x00020008, 0x00000208, + 0x00020000, 0x08020200, 0x08000200, 0x00000000, + 0x00000200, 0x00020008, 0x08020208, 0x08000200, + 0x08000008, 0x00000200, 0x00000000, 0x08020008, + 0x08000208, 0x00020000, 0x08000000, 0x08020208, + 0x00000008, 0x00020208, 0x00020200, 0x08000008, + 0x08020000, 0x08000208, 0x00000208, 0x08020000, + 0x00020208, 0x00000008, 0x08020008, 0x00020200}, + + {0x00802001, 0x00002081, 0x00002081, 0x00000080, + 0x00802080, 0x00800081, 0x00800001, 0x00002001, + 0x00000000, 0x00802000, 0x00802000, 0x00802081, + 0x00000081, 0x00000000, 0x00800080, 0x00800001, + 0x00000001, 0x00002000, 0x00800000, 0x00802001, + 0x00000080, 0x00800000, 0x00002001, 0x00002080, + 0x00800081, 0x00000001, 0x00002080, 0x00800080, + 0x00002000, 0x00802080, 0x00802081, 0x00000081, + 0x00800080, 0x00800001, 0x00802000, 0x00802081, + 0x00000081, 0x00000000, 0x00000000, 0x00802000, + 0x00002080, 0x00800080, 0x00800081, 0x00000001, + 0x00802001, 0x00002081, 0x00002081, 0x00000080, + 0x00802081, 0x00000081, 0x00000001, 0x00002000, + 0x00800001, 0x00002001, 0x00802080, 0x00800081, + 0x00002001, 0x00002080, 0x00800000, 0x00802001, + 0x00000080, 0x00800000, 0x00002000, 0x00802080}, + + {0x00000100, 0x02080100, 0x02080000, 0x42000100, + 0x00080000, 0x00000100, 0x40000000, 0x02080000, + 0x40080100, 0x00080000, 0x02000100, 0x40080100, + 0x42000100, 0x42080000, 0x00080100, 0x40000000, + 0x02000000, 0x40080000, 0x40080000, 0x00000000, + 0x40000100, 0x42080100, 0x42080100, 0x02000100, + 0x42080000, 0x40000100, 0x00000000, 0x42000000, + 0x02080100, 0x02000000, 0x42000000, 0x00080100, + 0x00080000, 0x42000100, 0x00000100, 0x02000000, + 0x40000000, 0x02080000, 0x42000100, 0x40080100, + 0x02000100, 0x40000000, 0x42080000, 0x02080100, + 0x40080100, 0x00000100, 0x02000000, 0x42080000, + 0x42080100, 0x00080100, 0x42000000, 0x42080100, + 0x02080000, 0x00000000, 0x40080000, 0x42000000, + 0x00080100, 0x02000100, 0x40000100, 0x00080000, + 0x00000000, 0x40080000, 0x02080100, 0x40000100}, + + {0x20000010, 0x20400000, 0x00004000, 0x20404010, + 0x20400000, 0x00000010, 0x20404010, 0x00400000, + 0x20004000, 0x00404010, 0x00400000, 0x20000010, + 0x00400010, 0x20004000, 0x20000000, 0x00004010, + 0x00000000, 0x00400010, 0x20004010, 0x00004000, + 0x00404000, 0x20004010, 0x00000010, 0x20400010, + 0x20400010, 0x00000000, 0x00404010, 0x20404000, + 0x00004010, 0x00404000, 0x20404000, 0x20000000, + 0x20004000, 0x00000010, 0x20400010, 0x00404000, + 0x20404010, 0x00400000, 0x00004010, 0x20000010, + 0x00400000, 0x20004000, 0x20000000, 0x00004010, + 0x20000010, 0x20404010, 0x00404000, 0x20400000, + 0x00404010, 0x20404000, 0x00000000, 0x20400010, + 0x00000010, 0x00004000, 0x20400000, 0x00404010, + 0x00004000, 0x00400010, 0x20004010, 0x00000000, + 0x20404000, 0x20000000, 0x00400010, 0x20004010}, + + {0x00200000, 0x04200002, 0x04000802, 0x00000000, + 0x00000800, 0x04000802, 0x00200802, 0x04200800, + 0x04200802, 0x00200000, 0x00000000, 0x04000002, + 0x00000002, 0x04000000, 0x04200002, 0x00000802, + 0x04000800, 0x00200802, 0x00200002, 0x04000800, + 0x04000002, 0x04200000, 0x04200800, 0x00200002, + 0x04200000, 0x00000800, 0x00000802, 0x04200802, + 0x00200800, 0x00000002, 0x04000000, 0x00200800, + 0x04000000, 0x00200800, 0x00200000, 0x04000802, + 0x04000802, 0x04200002, 0x04200002, 0x00000002, + 0x00200002, 0x04000000, 0x04000800, 0x00200000, + 0x04200800, 0x00000802, 0x00200802, 0x04200800, + 0x00000802, 0x04000002, 0x04200802, 0x04200000, + 0x00200800, 0x00000000, 0x00000002, 0x04200802, + 0x00000000, 0x00200802, 0x04200000, 0x00000800, + 0x04000002, 0x04000800, 0x00000800, 0x00200002}, + + {0x10001040, 0x00001000, 0x00040000, 0x10041040, + 0x10000000, 0x10001040, 0x00000040, 0x10000000, + 0x00040040, 0x10040000, 0x10041040, 0x00041000, + 0x10041000, 0x00041040, 0x00001000, 0x00000040, + 0x10040000, 0x10000040, 0x10001000, 0x00001040, + 0x00041000, 0x00040040, 0x10040040, 0x10041000, + 0x00001040, 0x00000000, 0x00000000, 0x10040040, + 0x10000040, 0x10001000, 0x00041040, 0x00040000, + 0x00041040, 0x00040000, 0x10041000, 0x00001000, + 0x00000040, 0x10040040, 0x00001000, 0x00041040, + 0x10001000, 0x00000040, 0x10000040, 0x10040000, + 0x10040040, 0x10000000, 0x00040000, 0x10001040, + 0x00000000, 0x10041040, 0x00040040, 0x10000040, + 0x10040000, 0x10001000, 0x10001040, 0x00000000, + 0x10041040, 0x00041000, 0x00041000, 0x00001040, + 0x00001040, 0x00040040, 0x10000000, 0x10041000} +}; + +#define f(R, K0246, K1357) (\ + s0246 = R ^ K0246, \ + s1357 = R ^ K1357, \ + s0246 = rotl(s0246, 28), \ + SPboxes[0] [(s0246 >> 24) & 0x3F] | \ + SPboxes[1] [(s1357 >> 24) & 0x3F] | \ + SPboxes[2] [(s0246 >> 16) & 0x3F] | \ + SPboxes[3] [(s1357 >> 16) & 0x3F] | \ + SPboxes[4] [(s0246 >> 8) & 0x3F] | \ + SPboxes[5] [(s1357 >> 8) & 0x3F] | \ + SPboxes[6] [(s0246 ) & 0x3F] | \ + SPboxes[7] [(s1357 ) & 0x3F]) + +#define bitswap(L, R, n, mask) (\ + swap = mask & ( (R >> n) ^ L ), \ + R ^= swap << n, \ + L ^= swap) + +/* Initial permutation */ +#define IP(L, R) (\ + bitswap(R, L, 4, 0x0F0F0F0F), \ + bitswap(R, L, 16, 0x0000FFFF), \ + bitswap(L, R, 2, 0x33333333), \ + bitswap(L, R, 8, 0x00FF00FF), \ + bitswap(R, L, 1, 0x55555555)) + +/* Final permutation */ +#define FP(L, R) (\ + bitswap(R, L, 1, 0x55555555), \ + bitswap(L, R, 8, 0x00FF00FF), \ + bitswap(L, R, 2, 0x33333333), \ + bitswap(R, L, 16, 0x0000FFFF), \ + bitswap(R, L, 4, 0x0F0F0F0F)) + +static void +des_encipher(quint32 *output, quint32 L, quint32 R, + struct des_context *sched) +{ + quint32 swap, s0246, s1357; + + IP(L, R); + + L = rotl(L, 1); + R = rotl(R, 1); + + L ^= f(R, sched->k0246[0], sched->k1357[0]); + R ^= f(L, sched->k0246[1], sched->k1357[1]); + L ^= f(R, sched->k0246[2], sched->k1357[2]); + R ^= f(L, sched->k0246[3], sched->k1357[3]); + L ^= f(R, sched->k0246[4], sched->k1357[4]); + R ^= f(L, sched->k0246[5], sched->k1357[5]); + L ^= f(R, sched->k0246[6], sched->k1357[6]); + R ^= f(L, sched->k0246[7], sched->k1357[7]); + L ^= f(R, sched->k0246[8], sched->k1357[8]); + R ^= f(L, sched->k0246[9], sched->k1357[9]); + L ^= f(R, sched->k0246[10], sched->k1357[10]); + R ^= f(L, sched->k0246[11], sched->k1357[11]); + L ^= f(R, sched->k0246[12], sched->k1357[12]); + R ^= f(L, sched->k0246[13], sched->k1357[13]); + L ^= f(R, sched->k0246[14], sched->k1357[14]); + R ^= f(L, sched->k0246[15], sched->k1357[15]); + + L = rotl(L, 31); + R = rotl(R, 31); + + swap = L; + L = R; + R = swap; + + FP(L, R); + + output[0] = L; + output[1] = R; +} + +#define GET_32BIT_MSB_FIRST(cp) \ + (((unsigned long)(unsigned char)(cp)[3]) | \ + ((unsigned long)(unsigned char)(cp)[2] << 8) | \ + ((unsigned long)(unsigned char)(cp)[1] << 16) | \ + ((unsigned long)(unsigned char)(cp)[0] << 24)) + +#define PUT_32BIT_MSB_FIRST(cp, value) do { \ + (cp)[3] = (value); \ + (cp)[2] = (value) >> 8; \ + (cp)[1] = (value) >> 16; \ + (cp)[0] = (value) >> 24; } while (0) + +static inline void +des_cbc_encrypt(unsigned char *dest, const unsigned char *src, + struct des_context *sched) +{ + quint32 out[2], L, R; + + L = GET_32BIT_MSB_FIRST(src); + R = GET_32BIT_MSB_FIRST(src + 4); + des_encipher(out, L, R, sched); + PUT_32BIT_MSB_FIRST(dest, out[0]); + PUT_32BIT_MSB_FIRST(dest + 4, out[1]); +} + + +static unsigned char * +deshash(unsigned char *dst, const unsigned char *key, + const unsigned char *src) +{ + struct des_context ctx; + + des_key_setup(GET_32BIT_MSB_FIRST(key) >> 8, + GET_32BIT_MSB_FIRST(key + 3), &ctx); + + des_cbc_encrypt(dst, src, &ctx); + + return dst; +} |