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Diffstat (limited to 'tools/plink/sshdes.c')
| -rw-r--r-- | tools/plink/sshdes.c | 1031 |
1 files changed, 1031 insertions, 0 deletions
diff --git a/tools/plink/sshdes.c b/tools/plink/sshdes.c new file mode 100644 index 000000000..0beb273ce --- /dev/null +++ b/tools/plink/sshdes.c @@ -0,0 +1,1031 @@ +#include <assert.h>
+#include "ssh.h"
+
+
+/* des.c - implementation of DES
+ */
+
+/*
+ * 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.
+ */
+
+typedef struct {
+ word32 k0246[16], k1357[16];
+ word32 iv0, iv1;
+} DESContext;
+
+#define rotl(x, c) ( (x << c) | (x >> (32-c)) )
+#define rotl28(x, c) ( ( (x << c) | (x >> (28-c)) ) & 0x0FFFFFFF)
+
+static word32 bitsel(word32 * input, const int *bitnums, int size)
+{
+ word32 ret = 0;
+ while (size--) {
+ int bitpos = *bitnums++;
+ ret <<= 1;
+ if (bitpos >= 0)
+ ret |= 1 & (input[bitpos / 32] >> (bitpos % 32));
+ }
+ return ret;
+}
+
+static void des_key_setup(word32 key_msw, word32 key_lsw, DESContext * sched)
+{
+
+ static const int PC1_Cbits[] = {
+ 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
+ };
+ static const int PC1_Dbits[] = {
+ 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
+ };
+ /*
+ * 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 };
+
+ word32 C, D;
+ word32 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);
+ }
+
+ sched->iv0 = sched->iv1 = 0;
+}
+
+static const word32 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, 0x01010004L},
+
+ {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, 0x00108000L},
+
+ {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, 0x00020200L},
+
+ {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, 0x00802080L},
+
+ {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, 0x40000100L},
+
+ {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, 0x20004010L},
+
+ {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, 0x00200002L},
+
+ {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, 0x10041000L}
+};
+
+#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(word32 * output, word32 L, word32 R,
+ DESContext * sched)
+{
+ word32 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;
+}
+
+static void des_decipher(word32 * output, word32 L, word32 R,
+ DESContext * sched)
+{
+ word32 swap, s0246, s1357;
+
+ IP(L, R);
+
+ L = rotl(L, 1);
+ R = rotl(R, 1);
+
+ L ^= f(R, sched->k0246[15], sched->k1357[15]);
+ R ^= f(L, sched->k0246[14], sched->k1357[14]);
+ L ^= f(R, sched->k0246[13], sched->k1357[13]);
+ R ^= f(L, sched->k0246[12], sched->k1357[12]);
+ L ^= f(R, sched->k0246[11], sched->k1357[11]);
+ R ^= f(L, sched->k0246[10], sched->k1357[10]);
+ L ^= f(R, sched->k0246[9], sched->k1357[9]);
+ R ^= f(L, sched->k0246[8], sched->k1357[8]);
+ L ^= f(R, sched->k0246[7], sched->k1357[7]);
+ R ^= f(L, sched->k0246[6], sched->k1357[6]);
+ L ^= f(R, sched->k0246[5], sched->k1357[5]);
+ R ^= f(L, sched->k0246[4], sched->k1357[4]);
+ L ^= f(R, sched->k0246[3], sched->k1357[3]);
+ R ^= f(L, sched->k0246[2], sched->k1357[2]);
+ L ^= f(R, sched->k0246[1], sched->k1357[1]);
+ R ^= f(L, sched->k0246[0], sched->k1357[0]);
+
+ L = rotl(L, 31);
+ R = rotl(R, 31);
+
+ swap = L;
+ L = R;
+ R = swap;
+
+ FP(L, R);
+
+ output[0] = L;
+ output[1] = R;
+}
+
+static void des_cbc_encrypt(unsigned char *blk,
+ unsigned int len, DESContext * sched)
+{
+ word32 out[2], iv0, iv1;
+ unsigned int i;
+
+ assert((len & 7) == 0);
+
+ iv0 = sched->iv0;
+ iv1 = sched->iv1;
+ for (i = 0; i < len; i += 8) {
+ iv0 ^= GET_32BIT_MSB_FIRST(blk);
+ iv1 ^= GET_32BIT_MSB_FIRST(blk + 4);
+ des_encipher(out, iv0, iv1, sched);
+ iv0 = out[0];
+ iv1 = out[1];
+ PUT_32BIT_MSB_FIRST(blk, iv0);
+ PUT_32BIT_MSB_FIRST(blk + 4, iv1);
+ blk += 8;
+ }
+ sched->iv0 = iv0;
+ sched->iv1 = iv1;
+}
+
+static void des_cbc_decrypt(unsigned char *blk,
+ unsigned int len, DESContext * sched)
+{
+ word32 out[2], iv0, iv1, xL, xR;
+ unsigned int i;
+
+ assert((len & 7) == 0);
+
+ iv0 = sched->iv0;
+ iv1 = sched->iv1;
+ for (i = 0; i < len; i += 8) {
+ xL = GET_32BIT_MSB_FIRST(blk);
+ xR = GET_32BIT_MSB_FIRST(blk + 4);
+ des_decipher(out, xL, xR, sched);
+ iv0 ^= out[0];
+ iv1 ^= out[1];
+ PUT_32BIT_MSB_FIRST(blk, iv0);
+ PUT_32BIT_MSB_FIRST(blk + 4, iv1);
+ blk += 8;
+ iv0 = xL;
+ iv1 = xR;
+ }
+ sched->iv0 = iv0;
+ sched->iv1 = iv1;
+}
+
+static void des_3cbc_encrypt(unsigned char *blk,
+ unsigned int len, DESContext * scheds)
+{
+ des_cbc_encrypt(blk, len, &scheds[0]);
+ des_cbc_decrypt(blk, len, &scheds[1]);
+ des_cbc_encrypt(blk, len, &scheds[2]);
+}
+
+static void des_cbc3_encrypt(unsigned char *blk,
+ unsigned int len, DESContext * scheds)
+{
+ word32 out[2], iv0, iv1;
+ unsigned int i;
+
+ assert((len & 7) == 0);
+
+ iv0 = scheds->iv0;
+ iv1 = scheds->iv1;
+ for (i = 0; i < len; i += 8) {
+ iv0 ^= GET_32BIT_MSB_FIRST(blk);
+ iv1 ^= GET_32BIT_MSB_FIRST(blk + 4);
+ des_encipher(out, iv0, iv1, &scheds[0]);
+ des_decipher(out, out[0], out[1], &scheds[1]);
+ des_encipher(out, out[0], out[1], &scheds[2]);
+ iv0 = out[0];
+ iv1 = out[1];
+ PUT_32BIT_MSB_FIRST(blk, iv0);
+ PUT_32BIT_MSB_FIRST(blk + 4, iv1);
+ blk += 8;
+ }
+ scheds->iv0 = iv0;
+ scheds->iv1 = iv1;
+}
+
+static void des_3cbc_decrypt(unsigned char *blk,
+ unsigned int len, DESContext * scheds)
+{
+ des_cbc_decrypt(blk, len, &scheds[2]);
+ des_cbc_encrypt(blk, len, &scheds[1]);
+ des_cbc_decrypt(blk, len, &scheds[0]);
+}
+
+static void des_cbc3_decrypt(unsigned char *blk,
+ unsigned int len, DESContext * scheds)
+{
+ word32 out[2], iv0, iv1, xL, xR;
+ unsigned int i;
+
+ assert((len & 7) == 0);
+
+ iv0 = scheds->iv0;
+ iv1 = scheds->iv1;
+ for (i = 0; i < len; i += 8) {
+ xL = GET_32BIT_MSB_FIRST(blk);
+ xR = GET_32BIT_MSB_FIRST(blk + 4);
+ des_decipher(out, xL, xR, &scheds[2]);
+ des_encipher(out, out[0], out[1], &scheds[1]);
+ des_decipher(out, out[0], out[1], &scheds[0]);
+ iv0 ^= out[0];
+ iv1 ^= out[1];
+ PUT_32BIT_MSB_FIRST(blk, iv0);
+ PUT_32BIT_MSB_FIRST(blk + 4, iv1);
+ blk += 8;
+ iv0 = xL;
+ iv1 = xR;
+ }
+ scheds->iv0 = iv0;
+ scheds->iv1 = iv1;
+}
+
+static void des_sdctr3(unsigned char *blk,
+ unsigned int len, DESContext * scheds)
+{
+ word32 b[2], iv0, iv1, tmp;
+ unsigned int i;
+
+ assert((len & 7) == 0);
+
+ iv0 = scheds->iv0;
+ iv1 = scheds->iv1;
+ for (i = 0; i < len; i += 8) {
+ des_encipher(b, iv0, iv1, &scheds[0]);
+ des_decipher(b, b[0], b[1], &scheds[1]);
+ des_encipher(b, b[0], b[1], &scheds[2]);
+ tmp = GET_32BIT_MSB_FIRST(blk);
+ PUT_32BIT_MSB_FIRST(blk, tmp ^ b[0]);
+ blk += 4;
+ tmp = GET_32BIT_MSB_FIRST(blk);
+ PUT_32BIT_MSB_FIRST(blk, tmp ^ b[1]);
+ blk += 4;
+ if ((iv1 = (iv1 + 1) & 0xffffffff) == 0)
+ iv0 = (iv0 + 1) & 0xffffffff;
+ }
+ scheds->iv0 = iv0;
+ scheds->iv1 = iv1;
+}
+
+static void *des3_make_context(void)
+{
+ return snewn(3, DESContext);
+}
+
+static void *des3_ssh1_make_context(void)
+{
+ /* Need 3 keys for each direction, in SSH-1 */
+ return snewn(6, DESContext);
+}
+
+static void *des_make_context(void)
+{
+ return snew(DESContext);
+}
+
+static void *des_ssh1_make_context(void)
+{
+ /* Need one key for each direction, in SSH-1 */
+ return snewn(2, DESContext);
+}
+
+static void des3_free_context(void *handle) /* used for both 3DES and DES */
+{
+ sfree(handle);
+}
+
+static void des3_key(void *handle, unsigned char *key)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &keys[0]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 8),
+ GET_32BIT_MSB_FIRST(key + 12), &keys[1]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 16),
+ GET_32BIT_MSB_FIRST(key + 20), &keys[2]);
+}
+
+static void des3_iv(void *handle, unsigned char *key)
+{
+ DESContext *keys = (DESContext *) handle;
+ keys[0].iv0 = GET_32BIT_MSB_FIRST(key);
+ keys[0].iv1 = GET_32BIT_MSB_FIRST(key + 4);
+}
+
+static void des_key(void *handle, unsigned char *key)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &keys[0]);
+}
+
+static void des3_sesskey(void *handle, unsigned char *key)
+{
+ DESContext *keys = (DESContext *) handle;
+ des3_key(keys, key);
+ des3_key(keys+3, key);
+}
+
+static void des3_encrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_3cbc_encrypt(blk, len, keys);
+}
+
+static void des3_decrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_3cbc_decrypt(blk, len, keys+3);
+}
+
+static void des3_ssh2_encrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_cbc3_encrypt(blk, len, keys);
+}
+
+static void des3_ssh2_decrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_cbc3_decrypt(blk, len, keys);
+}
+
+static void des3_ssh2_sdctr(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_sdctr3(blk, len, keys);
+}
+
+static void des_ssh2_encrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_cbc_encrypt(blk, len, keys);
+}
+
+static void des_ssh2_decrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_cbc_decrypt(blk, len, keys);
+}
+
+void des3_decrypt_pubkey(unsigned char *key, unsigned char *blk, int len)
+{
+ DESContext ourkeys[3];
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &ourkeys[0]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 8),
+ GET_32BIT_MSB_FIRST(key + 12), &ourkeys[1]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &ourkeys[2]);
+ des_3cbc_decrypt(blk, len, ourkeys);
+ memset(ourkeys, 0, sizeof(ourkeys));
+}
+
+void des3_encrypt_pubkey(unsigned char *key, unsigned char *blk, int len)
+{
+ DESContext ourkeys[3];
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &ourkeys[0]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 8),
+ GET_32BIT_MSB_FIRST(key + 12), &ourkeys[1]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &ourkeys[2]);
+ des_3cbc_encrypt(blk, len, ourkeys);
+ memset(ourkeys, 0, sizeof(ourkeys));
+}
+
+void des3_decrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
+ unsigned char *blk, int len)
+{
+ DESContext ourkeys[3];
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &ourkeys[0]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 8),
+ GET_32BIT_MSB_FIRST(key + 12), &ourkeys[1]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 16),
+ GET_32BIT_MSB_FIRST(key + 20), &ourkeys[2]);
+ ourkeys[0].iv0 = GET_32BIT_MSB_FIRST(iv);
+ ourkeys[0].iv1 = GET_32BIT_MSB_FIRST(iv+4);
+ des_cbc3_decrypt(blk, len, ourkeys);
+ memset(ourkeys, 0, sizeof(ourkeys));
+}
+
+void des3_encrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
+ unsigned char *blk, int len)
+{
+ DESContext ourkeys[3];
+ des_key_setup(GET_32BIT_MSB_FIRST(key),
+ GET_32BIT_MSB_FIRST(key + 4), &ourkeys[0]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 8),
+ GET_32BIT_MSB_FIRST(key + 12), &ourkeys[1]);
+ des_key_setup(GET_32BIT_MSB_FIRST(key + 16),
+ GET_32BIT_MSB_FIRST(key + 20), &ourkeys[2]);
+ ourkeys[0].iv0 = GET_32BIT_MSB_FIRST(iv);
+ ourkeys[0].iv1 = GET_32BIT_MSB_FIRST(iv+4);
+ des_cbc3_encrypt(blk, len, ourkeys);
+ memset(ourkeys, 0, sizeof(ourkeys));
+}
+
+static void des_keysetup_xdmauth(unsigned char *keydata, DESContext *dc)
+{
+ unsigned char key[8];
+ int i, nbits, j;
+ unsigned int bits;
+
+ bits = 0;
+ nbits = 0;
+ j = 0;
+ for (i = 0; i < 8; i++) {
+ if (nbits < 7) {
+ bits = (bits << 8) | keydata[j];
+ nbits += 8;
+ j++;
+ }
+ key[i] = (bits >> (nbits - 7)) << 1;
+ bits &= ~(0x7F << (nbits - 7));
+ nbits -= 7;
+ }
+
+ des_key_setup(GET_32BIT_MSB_FIRST(key), GET_32BIT_MSB_FIRST(key + 4), dc);
+}
+
+void des_encrypt_xdmauth(unsigned char *keydata, unsigned char *blk, int len)
+{
+ DESContext dc;
+ des_keysetup_xdmauth(keydata, &dc);
+ des_cbc_encrypt(blk, 24, &dc);
+}
+
+void des_decrypt_xdmauth(unsigned char *keydata, unsigned char *blk, int len)
+{
+ DESContext dc;
+ des_keysetup_xdmauth(keydata, &dc);
+ des_cbc_decrypt(blk, 24, &dc);
+}
+
+static const struct ssh2_cipher ssh_3des_ssh2 = {
+ des3_make_context, des3_free_context, des3_iv, des3_key,
+ des3_ssh2_encrypt_blk, des3_ssh2_decrypt_blk,
+ "3des-cbc",
+ 8, 168, SSH_CIPHER_IS_CBC, "triple-DES CBC"
+};
+
+static const struct ssh2_cipher ssh_3des_ssh2_ctr = {
+ des3_make_context, des3_free_context, des3_iv, des3_key,
+ des3_ssh2_sdctr, des3_ssh2_sdctr,
+ "3des-ctr",
+ 8, 168, 0, "triple-DES SDCTR"
+};
+
+/*
+ * Single DES in SSH-2. "des-cbc" is marked as HISTORIC in
+ * RFC 4250, referring to
+ * FIPS-46-3. ("Single DES (i.e., DES) will be permitted
+ * for legacy systems only.") , but ssh.com support it and
+ * apparently aren't the only people to do so, so we sigh
+ * and implement it anyway.
+ */
+static const struct ssh2_cipher ssh_des_ssh2 = {
+ des_make_context, des3_free_context, des3_iv, des_key,
+ des_ssh2_encrypt_blk, des_ssh2_decrypt_blk,
+ "des-cbc",
+ 8, 56, SSH_CIPHER_IS_CBC, "single-DES CBC"
+};
+
+static const struct ssh2_cipher ssh_des_sshcom_ssh2 = {
+ des_make_context, des3_free_context, des3_iv, des_key,
+ des_ssh2_encrypt_blk, des_ssh2_decrypt_blk,
+ "des-cbc@ssh.com",
+ 8, 56, SSH_CIPHER_IS_CBC, "single-DES CBC"
+};
+
+static const struct ssh2_cipher *const des3_list[] = {
+ &ssh_3des_ssh2_ctr,
+ &ssh_3des_ssh2
+};
+
+const struct ssh2_ciphers ssh2_3des = {
+ sizeof(des3_list) / sizeof(*des3_list),
+ des3_list
+};
+
+static const struct ssh2_cipher *const des_list[] = {
+ &ssh_des_ssh2,
+ &ssh_des_sshcom_ssh2
+};
+
+const struct ssh2_ciphers ssh2_des = {
+ sizeof(des_list) / sizeof(*des_list),
+ des_list
+};
+
+const struct ssh_cipher ssh_3des = {
+ des3_ssh1_make_context, des3_free_context, des3_sesskey,
+ des3_encrypt_blk, des3_decrypt_blk,
+ 8, "triple-DES inner-CBC"
+};
+
+static void des_sesskey(void *handle, unsigned char *key)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_key(keys, key);
+ des_key(keys+1, key);
+}
+
+static void des_encrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_cbc_encrypt(blk, len, keys);
+}
+
+static void des_decrypt_blk(void *handle, unsigned char *blk, int len)
+{
+ DESContext *keys = (DESContext *) handle;
+ des_cbc_decrypt(blk, len, keys+1);
+}
+
+const struct ssh_cipher ssh_des = {
+ des_ssh1_make_context, des3_free_context, des_sesskey,
+ des_encrypt_blk, des_decrypt_blk,
+ 8, "single-DES CBC"
+};
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