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1 | #include <assert.h> |
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2 | #include <stdio.h> /* FIXME */ |
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3 | #include <stdarg.h> /* FIXME */ |
4 | #include <windows.h> /* FIXME */ |
5 | #include "putty.h" /* FIXME */ |
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6 | #include "ssh.h" |
7 | |
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8 | |
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9 | /* des.c - implementation of DES |
10 | */ |
11 | |
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12 | /* |
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13 | * Description of DES |
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14 | * ------------------ |
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15 | * |
16 | * Unlike the description in FIPS 46, I'm going to use _sensible_ indices: |
17 | * bits in an n-bit word are numbered from 0 at the LSB to n-1 at the MSB. |
18 | * And S-boxes are indexed by six consecutive bits, not by the outer two |
19 | * followed by the middle four. |
20 | * |
21 | * The DES encryption routine requires a 64-bit input, and a key schedule K |
22 | * containing 16 48-bit elements. |
23 | * |
24 | * First the input is permuted by the initial permutation IP. |
25 | * Then the input is split into 32-bit words L and R. (L is the MSW.) |
26 | * Next, 16 rounds. In each round: |
27 | * (L, R) <- (R, L xor f(R, K[i])) |
28 | * Then the pre-output words L and R are swapped. |
29 | * Then L and R are glued back together into a 64-bit word. (L is the MSW, |
30 | * again, but since we just swapped them, the MSW is the R that came out |
31 | * of the last round.) |
32 | * The 64-bit output block is permuted by the inverse of IP and returned. |
33 | * |
34 | * Decryption is identical except that the elements of K are used in the |
35 | * opposite order. (This wouldn't work if that word swap didn't happen.) |
36 | * |
37 | * The function f, used in each round, accepts a 32-bit word R and a |
38 | * 48-bit key block K. It produces a 32-bit output. |
39 | * |
40 | * First R is expanded to 48 bits using the bit-selection function E. |
41 | * The resulting 48-bit block is XORed with the key block K to produce |
42 | * a 48-bit block X. |
43 | * This block X is split into eight groups of 6 bits. Each group of 6 |
44 | * bits is then looked up in one of the eight S-boxes to convert |
45 | * it to 4 bits. These eight groups of 4 bits are glued back |
46 | * together to produce a 32-bit preoutput block. |
47 | * The preoutput block is permuted using the permutation P and returned. |
48 | * |
49 | * Key setup maps a 64-bit key word into a 16x48-bit key schedule. Although |
50 | * the approved input format for the key is a 64-bit word, eight of the |
51 | * bits are discarded, so the actual quantity of key used is 56 bits. |
52 | * |
53 | * First the input key is converted to two 28-bit words C and D using |
54 | * the bit-selection function PC1. |
55 | * Then 16 rounds of key setup occur. In each round, C and D are each |
56 | * rotated left by either 1 or 2 bits (depending on which round), and |
57 | * then converted into a key schedule element using the bit-selection |
58 | * function PC2. |
59 | * |
60 | * That's the actual algorithm. Now for the tedious details: all those |
61 | * painful permutations and lookup tables. |
62 | * |
63 | * IP is a 64-to-64 bit permutation. Its output contains the following |
64 | * bits of its input (listed in order MSB to LSB of output). |
65 | * |
66 | * 6 14 22 30 38 46 54 62 4 12 20 28 36 44 52 60 |
67 | * 2 10 18 26 34 42 50 58 0 8 16 24 32 40 48 56 |
68 | * 7 15 23 31 39 47 55 63 5 13 21 29 37 45 53 61 |
69 | * 3 11 19 27 35 43 51 59 1 9 17 25 33 41 49 57 |
70 | * |
71 | * E is a 32-to-48 bit selection function. Its output contains the following |
72 | * bits of its input (listed in order MSB to LSB of output). |
73 | * |
74 | * 0 31 30 29 28 27 28 27 26 25 24 23 24 23 22 21 20 19 20 19 18 17 16 15 |
75 | * 16 15 14 13 12 11 12 11 10 9 8 7 8 7 6 5 4 3 4 3 2 1 0 31 |
76 | * |
77 | * The S-boxes are arbitrary table-lookups each mapping a 6-bit input to a |
78 | * 4-bit output. In other words, each S-box is an array[64] of 4-bit numbers. |
79 | * The S-boxes are listed below. The first S-box listed is applied to the |
80 | * most significant six bits of the block X; the last one is applied to the |
81 | * least significant. |
82 | * |
83 | * 14 0 4 15 13 7 1 4 2 14 15 2 11 13 8 1 |
84 | * 3 10 10 6 6 12 12 11 5 9 9 5 0 3 7 8 |
85 | * 4 15 1 12 14 8 8 2 13 4 6 9 2 1 11 7 |
86 | * 15 5 12 11 9 3 7 14 3 10 10 0 5 6 0 13 |
87 | * |
88 | * 15 3 1 13 8 4 14 7 6 15 11 2 3 8 4 14 |
89 | * 9 12 7 0 2 1 13 10 12 6 0 9 5 11 10 5 |
90 | * 0 13 14 8 7 10 11 1 10 3 4 15 13 4 1 2 |
91 | * 5 11 8 6 12 7 6 12 9 0 3 5 2 14 15 9 |
92 | * |
93 | * 10 13 0 7 9 0 14 9 6 3 3 4 15 6 5 10 |
94 | * 1 2 13 8 12 5 7 14 11 12 4 11 2 15 8 1 |
95 | * 13 1 6 10 4 13 9 0 8 6 15 9 3 8 0 7 |
96 | * 11 4 1 15 2 14 12 3 5 11 10 5 14 2 7 12 |
97 | * |
98 | * 7 13 13 8 14 11 3 5 0 6 6 15 9 0 10 3 |
99 | * 1 4 2 7 8 2 5 12 11 1 12 10 4 14 15 9 |
100 | * 10 3 6 15 9 0 0 6 12 10 11 1 7 13 13 8 |
101 | * 15 9 1 4 3 5 14 11 5 12 2 7 8 2 4 14 |
102 | * |
103 | * 2 14 12 11 4 2 1 12 7 4 10 7 11 13 6 1 |
104 | * 8 5 5 0 3 15 15 10 13 3 0 9 14 8 9 6 |
105 | * 4 11 2 8 1 12 11 7 10 1 13 14 7 2 8 13 |
106 | * 15 6 9 15 12 0 5 9 6 10 3 4 0 5 14 3 |
107 | * |
108 | * 12 10 1 15 10 4 15 2 9 7 2 12 6 9 8 5 |
109 | * 0 6 13 1 3 13 4 14 14 0 7 11 5 3 11 8 |
110 | * 9 4 14 3 15 2 5 12 2 9 8 5 12 15 3 10 |
111 | * 7 11 0 14 4 1 10 7 1 6 13 0 11 8 6 13 |
112 | * |
113 | * 4 13 11 0 2 11 14 7 15 4 0 9 8 1 13 10 |
114 | * 3 14 12 3 9 5 7 12 5 2 10 15 6 8 1 6 |
115 | * 1 6 4 11 11 13 13 8 12 1 3 4 7 10 14 7 |
116 | * 10 9 15 5 6 0 8 15 0 14 5 2 9 3 2 12 |
117 | * |
118 | * 13 1 2 15 8 13 4 8 6 10 15 3 11 7 1 4 |
119 | * 10 12 9 5 3 6 14 11 5 0 0 14 12 9 7 2 |
120 | * 7 2 11 1 4 14 1 7 9 4 12 10 14 8 2 13 |
121 | * 0 15 6 12 10 9 13 0 15 3 3 5 5 6 8 11 |
122 | * |
123 | * P is a 32-to-32 bit permutation. Its output contains the following |
124 | * bits of its input (listed in order MSB to LSB of output). |
125 | * |
126 | * 16 25 12 11 3 20 4 15 31 17 9 6 27 14 1 22 |
127 | * 30 24 8 18 0 5 29 23 13 19 2 26 10 21 28 7 |
128 | * |
129 | * PC1 is a 64-to-56 bit selection function. Its output is in two words, |
130 | * C and D. The word C contains the following bits of its input (listed |
131 | * in order MSB to LSB of output). |
132 | * |
133 | * 7 15 23 31 39 47 55 63 6 14 22 30 38 46 |
134 | * 54 62 5 13 21 29 37 45 53 61 4 12 20 28 |
135 | * |
136 | * And the word D contains these bits. |
137 | * |
138 | * 1 9 17 25 33 41 49 57 2 10 18 26 34 42 |
139 | * 50 58 3 11 19 27 35 43 51 59 36 44 52 60 |
140 | * |
141 | * PC2 is a 56-to-48 bit selection function. Its input is in two words, |
142 | * C and D. These are treated as one 56-bit word (with C more significant, |
143 | * so that bits 55 to 28 of the word are bits 27 to 0 of C, and bits 27 to |
144 | * 0 of the word are bits 27 to 0 of D). The output contains the following |
145 | * bits of this 56-bit input word (listed in order MSB to LSB of output). |
146 | * |
147 | * 42 39 45 32 55 51 53 28 41 50 35 46 33 37 44 52 30 48 40 49 29 36 43 54 |
148 | * 15 4 25 19 9 1 26 16 5 11 23 8 12 7 17 0 22 3 10 14 6 20 27 24 |
149 | */ |
150 | |
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151 | /* |
152 | * Implementation details |
153 | * ---------------------- |
154 | * |
155 | * If you look at the code in this module, you'll find it looks |
156 | * nothing _like_ the above algorithm. Here I explain the |
157 | * differences... |
158 | * |
159 | * Key setup has not been heavily optimised here. We are not |
160 | * concerned with key agility: we aren't codebreakers. We don't |
161 | * mind a little delay (and it really is a little one; it may be a |
162 | * factor of five or so slower than it could be but it's still not |
163 | * an appreciable length of time) while setting up. The only tweaks |
164 | * in the key setup are ones which change the format of the key |
165 | * schedule to speed up the actual encryption. I'll describe those |
166 | * below. |
167 | * |
168 | * The first and most obvious optimisation is the S-boxes. Since |
169 | * each S-box always targets the same four bits in the final 32-bit |
170 | * word, so the output from (for example) S-box 0 must always be |
171 | * shifted left 28 bits, we can store the already-shifted outputs |
172 | * in the lookup tables. This reduces lookup-and-shift to lookup, |
173 | * so the S-box step is now just a question of ORing together eight |
174 | * table lookups. |
175 | * |
176 | * The permutation P is just a bit order change; it's invariant |
177 | * with respect to OR, in that P(x)|P(y) = P(x|y). Therefore, we |
178 | * can apply P to every entry of the S-box tables and then we don't |
179 | * have to do it in the code of f(). This yields a set of tables |
180 | * which might be called SP-boxes. |
181 | * |
182 | * The bit-selection function E is our next target. Note that E is |
183 | * immediately followed by the operation of splitting into 6-bit |
184 | * chunks. Examining the 6-bit chunks coming out of E we notice |
185 | * they're all contiguous within the word (speaking cyclically - |
186 | * the end two wrap round); so we can extract those bit strings |
187 | * individually rather than explicitly running E. This would yield |
188 | * code such as |
189 | * |
190 | * y |= SPboxes[0][ (rotl(R, 5) ^ top6bitsofK) & 0x3F ]; |
191 | * t |= SPboxes[1][ (rotl(R,11) ^ next6bitsofK) & 0x3F ]; |
192 | * |
193 | * and so on; and the key schedule preparation would have to |
194 | * provide each 6-bit chunk separately. |
195 | * |
196 | * Really we'd like to XOR in the key schedule element before |
197 | * looking up bit strings in R. This we can't do, naively, because |
198 | * the 6-bit strings we want overlap. But look at the strings: |
199 | * |
200 | * 3322222222221111111111 |
201 | * bit 10987654321098765432109876543210 |
202 | * |
203 | * box0 XXXXX X |
204 | * box1 XXXXXX |
205 | * box2 XXXXXX |
206 | * box3 XXXXXX |
207 | * box4 XXXXXX |
208 | * box5 XXXXXX |
209 | * box6 XXXXXX |
210 | * box7 X XXXXX |
211 | * |
212 | * The bit strings we need to XOR in for boxes 0, 2, 4 and 6 don't |
213 | * overlap with each other. Neither do the ones for boxes 1, 3, 5 |
214 | * and 7. So we could provide the key schedule in the form of two |
215 | * words that we can separately XOR into R, and then every S-box |
216 | * index is available as a (cyclically) contiguous 6-bit substring |
217 | * of one or the other of the results. |
218 | * |
219 | * The comments in Eric Young's libdes implementation point out |
220 | * that two of these bit strings require a rotation (rather than a |
221 | * simple shift) to extract. It's unavoidable that at least _one_ |
222 | * must do; but we can actually run the whole inner algorithm (all |
223 | * 16 rounds) rotated one bit to the left, so that what the `real' |
224 | * DES description sees as L=0x80000001 we see as L=0x00000003. |
225 | * This requires rotating all our SP-box entries one bit to the |
226 | * left, and rotating each word of the key schedule elements one to |
227 | * the left, and rotating L and R one bit left just after IP and |
228 | * one bit right again just before FP. And in each round we convert |
229 | * a rotate into a shift, so we've saved a few per cent. |
230 | * |
231 | * That's about it for the inner loop; the SP-box tables as listed |
232 | * below are what I've described here (the original S value, |
233 | * shifted to its final place in the input to P, run through P, and |
234 | * then rotated one bit left). All that remains is to optimise the |
235 | * initial permutation IP. |
236 | * |
237 | * IP is not an arbitrary permutation. It has the nice property |
238 | * that if you take any bit number, write it in binary (6 bits), |
239 | * permute those 6 bits and invert some of them, you get the final |
240 | * position of that bit. Specifically, the bit whose initial |
241 | * position is given (in binary) as fedcba ends up in position |
242 | * AcbFED (where a capital letter denotes the inverse of a bit). |
243 | * |
244 | * We have the 64-bit data in two 32-bit words L and R, where bits |
245 | * in L are those with f=1 and bits in R are those with f=0. We |
246 | * note that we can do a simple transformation: suppose we exchange |
247 | * the bits with f=1,c=0 and the bits with f=0,c=1. This will cause |
248 | * the bit fedcba to be in position cedfba - we've `swapped' bits c |
249 | * and f in the position of each bit! |
250 | * |
251 | * Better still, this transformation is easy. In the example above, |
252 | * bits in L with c=0 are bits 0x0F0F0F0F, and those in R with c=1 |
253 | * are 0xF0F0F0F0. So we can do |
254 | * |
255 | * difference = ((R >> 4) ^ L) & 0x0F0F0F0F |
256 | * R ^= (difference << 4) |
257 | * L ^= difference |
258 | * |
259 | * to perform the swap. Let's denote this by bitswap(4,0x0F0F0F0F). |
260 | * Also, we can invert the bit at the top just by exchanging L and |
261 | * R. So in a few swaps and a few of these bit operations we can |
262 | * do: |
263 | * |
264 | * Initially the position of bit fedcba is fedcba |
265 | * Swap L with R to make it Fedcba |
266 | * Perform bitswap( 4,0x0F0F0F0F) to make it cedFba |
267 | * Perform bitswap(16,0x0000FFFF) to make it ecdFba |
268 | * Swap L with R to make it EcdFba |
269 | * Perform bitswap( 2,0x33333333) to make it bcdFEa |
270 | * Perform bitswap( 8,0x00FF00FF) to make it dcbFEa |
271 | * Swap L with R to make it DcbFEa |
272 | * Perform bitswap( 1,0x55555555) to make it acbFED |
273 | * Swap L with R to make it AcbFED |
274 | * |
275 | * (In the actual code the four swaps are implicit: R and L are |
276 | * simply used the other way round in the first, second and last |
277 | * bitswap operations.) |
278 | * |
279 | * The final permutation is just the inverse of IP, so it can be |
280 | * performed by a similar set of operations. |
281 | */ |
282 | |
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283 | typedef struct { |
284 | word32 k0246[16], k1357[16]; |
285 | word32 eiv0, eiv1; |
286 | word32 div0, div1; |
287 | } DESContext; |
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288 | |
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289 | #define rotl(x, c) ( (x << c) | (x >> (32-c)) ) |
290 | #define rotl28(x, c) ( ( (x << c) | (x >> (28-c)) ) & 0x0FFFFFFF) |
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291 | |
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292 | static word32 bitsel(word32 *input, const int *bitnums, int size) { |
293 | word32 ret = 0; |
294 | while (size--) { |
295 | int bitpos = *bitnums++; |
296 | ret <<= 1; |
297 | if (bitpos >= 0) |
298 | ret |= 1 & (input[bitpos / 32] >> (bitpos % 32)); |
299 | } |
300 | return ret; |
301 | } |
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302 | |
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303 | void des_key_setup(word32 key_msw, word32 key_lsw, DESContext *sched) { |
304 | |
305 | static const int PC1_Cbits[] = { |
306 | 7, 15, 23, 31, 39, 47, 55, 63, 6, 14, 22, 30, 38, 46, |
307 | 54, 62, 5, 13, 21, 29, 37, 45, 53, 61, 4, 12, 20, 28 |
308 | }; |
309 | static const int PC1_Dbits[] = { |
310 | 1, 9, 17, 25, 33, 41, 49, 57, 2, 10, 18, 26, 34, 42, |
311 | 50, 58, 3, 11, 19, 27, 35, 43, 51, 59, 36, 44, 52, 60 |
312 | }; |
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313 | /* |
314 | * The bit numbers in the two lists below don't correspond to |
315 | * the ones in the above description of PC2, because in the |
316 | * above description C and D are concatenated so `bit 28' means |
317 | * bit 0 of C. In this implementation we're using the standard |
318 | * `bitsel' function above and C is in the second word, so bit |
319 | * 0 of C is addressed by writing `32' here. |
320 | */ |
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321 | static const int PC2_0246[] = { |
322 | 49, 36, 59, 55, -1, -1, 37, 41, 48, 56, 34, 52, -1, -1, 15, 4, |
323 | 25, 19, 9, 1, -1, -1, 12, 7, 17, 0, 22, 3, -1, -1, 46, 43 |
324 | }; |
325 | static const int PC2_1357[] = { |
326 | -1, -1, 57, 32, 45, 54, 39, 50, -1, -1, 44, 53, 33, 40, 47, 58, |
327 | -1, -1, 26, 16, 5, 11, 23, 8, -1, -1, 10, 14, 6, 20, 27, 24 |
328 | }; |
329 | static const int leftshifts[] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1}; |
330 | |
331 | word32 C, D; |
332 | word32 buf[2]; |
333 | int i; |
334 | |
335 | buf[0] = key_lsw; |
336 | buf[1] = key_msw; |
337 | |
338 | C = bitsel(buf, PC1_Cbits, 28); |
339 | D = bitsel(buf, PC1_Dbits, 28); |
340 | |
341 | for (i = 0; i < 16; i++) { |
342 | C = rotl28(C, leftshifts[i]); |
343 | D = rotl28(D, leftshifts[i]); |
344 | buf[0] = D; |
345 | buf[1] = C; |
346 | sched->k0246[i] = bitsel(buf, PC2_0246, 32); |
347 | sched->k1357[i] = bitsel(buf, PC2_1357, 32); |
348 | } |
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349 | |
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350 | sched->eiv0 = sched->eiv1 = 0; |
351 | sched->div0 = sched->div1 = 0; /* for good measure */ |
352 | } |
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353 | |
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354 | static const word32 SPboxes[8][64] = { |
355 | {0x01010400, 0x00000000, 0x00010000, 0x01010404, |
356 | 0x01010004, 0x00010404, 0x00000004, 0x00010000, |
357 | 0x00000400, 0x01010400, 0x01010404, 0x00000400, |
358 | 0x01000404, 0x01010004, 0x01000000, 0x00000004, |
359 | 0x00000404, 0x01000400, 0x01000400, 0x00010400, |
360 | 0x00010400, 0x01010000, 0x01010000, 0x01000404, |
361 | 0x00010004, 0x01000004, 0x01000004, 0x00010004, |
362 | 0x00000000, 0x00000404, 0x00010404, 0x01000000, |
363 | 0x00010000, 0x01010404, 0x00000004, 0x01010000, |
364 | 0x01010400, 0x01000000, 0x01000000, 0x00000400, |
365 | 0x01010004, 0x00010000, 0x00010400, 0x01000004, |
366 | 0x00000400, 0x00000004, 0x01000404, 0x00010404, |
367 | 0x01010404, 0x00010004, 0x01010000, 0x01000404, |
368 | 0x01000004, 0x00000404, 0x00010404, 0x01010400, |
369 | 0x00000404, 0x01000400, 0x01000400, 0x00000000, |
370 | 0x00010004, 0x00010400, 0x00000000, 0x01010004L}, |
371 | |
372 | {0x80108020, 0x80008000, 0x00008000, 0x00108020, |
373 | 0x00100000, 0x00000020, 0x80100020, 0x80008020, |
374 | 0x80000020, 0x80108020, 0x80108000, 0x80000000, |
375 | 0x80008000, 0x00100000, 0x00000020, 0x80100020, |
376 | 0x00108000, 0x00100020, 0x80008020, 0x00000000, |
377 | 0x80000000, 0x00008000, 0x00108020, 0x80100000, |
378 | 0x00100020, 0x80000020, 0x00000000, 0x00108000, |
379 | 0x00008020, 0x80108000, 0x80100000, 0x00008020, |
380 | 0x00000000, 0x00108020, 0x80100020, 0x00100000, |
381 | 0x80008020, 0x80100000, 0x80108000, 0x00008000, |
382 | 0x80100000, 0x80008000, 0x00000020, 0x80108020, |
383 | 0x00108020, 0x00000020, 0x00008000, 0x80000000, |
384 | 0x00008020, 0x80108000, 0x00100000, 0x80000020, |
385 | 0x00100020, 0x80008020, 0x80000020, 0x00100020, |
386 | 0x00108000, 0x00000000, 0x80008000, 0x00008020, |
387 | 0x80000000, 0x80100020, 0x80108020, 0x00108000L}, |
388 | |
389 | {0x00000208, 0x08020200, 0x00000000, 0x08020008, |
390 | 0x08000200, 0x00000000, 0x00020208, 0x08000200, |
391 | 0x00020008, 0x08000008, 0x08000008, 0x00020000, |
392 | 0x08020208, 0x00020008, 0x08020000, 0x00000208, |
393 | 0x08000000, 0x00000008, 0x08020200, 0x00000200, |
394 | 0x00020200, 0x08020000, 0x08020008, 0x00020208, |
395 | 0x08000208, 0x00020200, 0x00020000, 0x08000208, |
396 | 0x00000008, 0x08020208, 0x00000200, 0x08000000, |
397 | 0x08020200, 0x08000000, 0x00020008, 0x00000208, |
398 | 0x00020000, 0x08020200, 0x08000200, 0x00000000, |
399 | 0x00000200, 0x00020008, 0x08020208, 0x08000200, |
400 | 0x08000008, 0x00000200, 0x00000000, 0x08020008, |
401 | 0x08000208, 0x00020000, 0x08000000, 0x08020208, |
402 | 0x00000008, 0x00020208, 0x00020200, 0x08000008, |
403 | 0x08020000, 0x08000208, 0x00000208, 0x08020000, |
404 | 0x00020208, 0x00000008, 0x08020008, 0x00020200L}, |
405 | |
406 | {0x00802001, 0x00002081, 0x00002081, 0x00000080, |
407 | 0x00802080, 0x00800081, 0x00800001, 0x00002001, |
408 | 0x00000000, 0x00802000, 0x00802000, 0x00802081, |
409 | 0x00000081, 0x00000000, 0x00800080, 0x00800001, |
410 | 0x00000001, 0x00002000, 0x00800000, 0x00802001, |
411 | 0x00000080, 0x00800000, 0x00002001, 0x00002080, |
412 | 0x00800081, 0x00000001, 0x00002080, 0x00800080, |
413 | 0x00002000, 0x00802080, 0x00802081, 0x00000081, |
414 | 0x00800080, 0x00800001, 0x00802000, 0x00802081, |
415 | 0x00000081, 0x00000000, 0x00000000, 0x00802000, |
416 | 0x00002080, 0x00800080, 0x00800081, 0x00000001, |
417 | 0x00802001, 0x00002081, 0x00002081, 0x00000080, |
418 | 0x00802081, 0x00000081, 0x00000001, 0x00002000, |
419 | 0x00800001, 0x00002001, 0x00802080, 0x00800081, |
420 | 0x00002001, 0x00002080, 0x00800000, 0x00802001, |
421 | 0x00000080, 0x00800000, 0x00002000, 0x00802080L}, |
422 | |
423 | {0x00000100, 0x02080100, 0x02080000, 0x42000100, |
424 | 0x00080000, 0x00000100, 0x40000000, 0x02080000, |
425 | 0x40080100, 0x00080000, 0x02000100, 0x40080100, |
426 | 0x42000100, 0x42080000, 0x00080100, 0x40000000, |
427 | 0x02000000, 0x40080000, 0x40080000, 0x00000000, |
428 | 0x40000100, 0x42080100, 0x42080100, 0x02000100, |
429 | 0x42080000, 0x40000100, 0x00000000, 0x42000000, |
430 | 0x02080100, 0x02000000, 0x42000000, 0x00080100, |
431 | 0x00080000, 0x42000100, 0x00000100, 0x02000000, |
432 | 0x40000000, 0x02080000, 0x42000100, 0x40080100, |
433 | 0x02000100, 0x40000000, 0x42080000, 0x02080100, |
434 | 0x40080100, 0x00000100, 0x02000000, 0x42080000, |
435 | 0x42080100, 0x00080100, 0x42000000, 0x42080100, |
436 | 0x02080000, 0x00000000, 0x40080000, 0x42000000, |
437 | 0x00080100, 0x02000100, 0x40000100, 0x00080000, |
438 | 0x00000000, 0x40080000, 0x02080100, 0x40000100L}, |
439 | |
440 | {0x20000010, 0x20400000, 0x00004000, 0x20404010, |
441 | 0x20400000, 0x00000010, 0x20404010, 0x00400000, |
442 | 0x20004000, 0x00404010, 0x00400000, 0x20000010, |
443 | 0x00400010, 0x20004000, 0x20000000, 0x00004010, |
444 | 0x00000000, 0x00400010, 0x20004010, 0x00004000, |
445 | 0x00404000, 0x20004010, 0x00000010, 0x20400010, |
446 | 0x20400010, 0x00000000, 0x00404010, 0x20404000, |
447 | 0x00004010, 0x00404000, 0x20404000, 0x20000000, |
448 | 0x20004000, 0x00000010, 0x20400010, 0x00404000, |
449 | 0x20404010, 0x00400000, 0x00004010, 0x20000010, |
450 | 0x00400000, 0x20004000, 0x20000000, 0x00004010, |
451 | 0x20000010, 0x20404010, 0x00404000, 0x20400000, |
452 | 0x00404010, 0x20404000, 0x00000000, 0x20400010, |
453 | 0x00000010, 0x00004000, 0x20400000, 0x00404010, |
454 | 0x00004000, 0x00400010, 0x20004010, 0x00000000, |
455 | 0x20404000, 0x20000000, 0x00400010, 0x20004010L}, |
456 | |
457 | {0x00200000, 0x04200002, 0x04000802, 0x00000000, |
458 | 0x00000800, 0x04000802, 0x00200802, 0x04200800, |
459 | 0x04200802, 0x00200000, 0x00000000, 0x04000002, |
460 | 0x00000002, 0x04000000, 0x04200002, 0x00000802, |
461 | 0x04000800, 0x00200802, 0x00200002, 0x04000800, |
462 | 0x04000002, 0x04200000, 0x04200800, 0x00200002, |
463 | 0x04200000, 0x00000800, 0x00000802, 0x04200802, |
464 | 0x00200800, 0x00000002, 0x04000000, 0x00200800, |
465 | 0x04000000, 0x00200800, 0x00200000, 0x04000802, |
466 | 0x04000802, 0x04200002, 0x04200002, 0x00000002, |
467 | 0x00200002, 0x04000000, 0x04000800, 0x00200000, |
468 | 0x04200800, 0x00000802, 0x00200802, 0x04200800, |
469 | 0x00000802, 0x04000002, 0x04200802, 0x04200000, |
470 | 0x00200800, 0x00000000, 0x00000002, 0x04200802, |
471 | 0x00000000, 0x00200802, 0x04200000, 0x00000800, |
472 | 0x04000002, 0x04000800, 0x00000800, 0x00200002L}, |
473 | |
474 | {0x10001040, 0x00001000, 0x00040000, 0x10041040, |
475 | 0x10000000, 0x10001040, 0x00000040, 0x10000000, |
476 | 0x00040040, 0x10040000, 0x10041040, 0x00041000, |
477 | 0x10041000, 0x00041040, 0x00001000, 0x00000040, |
478 | 0x10040000, 0x10000040, 0x10001000, 0x00001040, |
479 | 0x00041000, 0x00040040, 0x10040040, 0x10041000, |
480 | 0x00001040, 0x00000000, 0x00000000, 0x10040040, |
481 | 0x10000040, 0x10001000, 0x00041040, 0x00040000, |
482 | 0x00041040, 0x00040000, 0x10041000, 0x00001000, |
483 | 0x00000040, 0x10040040, 0x00001000, 0x00041040, |
484 | 0x10001000, 0x00000040, 0x10000040, 0x10040000, |
485 | 0x10040040, 0x10000000, 0x00040000, 0x10001040, |
486 | 0x00000000, 0x10041040, 0x00040040, 0x10000040, |
487 | 0x10040000, 0x10001000, 0x10001040, 0x00000000, |
488 | 0x10041040, 0x00041000, 0x00041000, 0x00001040, |
489 | 0x00001040, 0x00040040, 0x10000000, 0x10041000L} |
490 | }; |
374330e2 |
491 | |
d1e726bc |
492 | #define f(R, K0246, K1357) (\ |
493 | s0246 = R ^ K0246, \ |
494 | s1357 = R ^ K1357, \ |
495 | s0246 = rotl(s0246, 28), \ |
496 | SPboxes[0] [(s0246 >> 24) & 0x3F] | \ |
497 | SPboxes[1] [(s1357 >> 24) & 0x3F] | \ |
498 | SPboxes[2] [(s0246 >> 16) & 0x3F] | \ |
499 | SPboxes[3] [(s1357 >> 16) & 0x3F] | \ |
500 | SPboxes[4] [(s0246 >> 8) & 0x3F] | \ |
501 | SPboxes[5] [(s1357 >> 8) & 0x3F] | \ |
502 | SPboxes[6] [(s0246 ) & 0x3F] | \ |
503 | SPboxes[7] [(s1357 ) & 0x3F]) |
504 | |
505 | #define bitswap(L, R, n, mask) (\ |
506 | swap = mask & ( (R >> n) ^ L ), \ |
507 | R ^= swap << n, \ |
508 | L ^= swap) |
509 | |
510 | /* Initial permutation */ |
511 | #define IP(L, R) (\ |
512 | bitswap(R, L, 4, 0x0F0F0F0F), \ |
513 | bitswap(R, L, 16, 0x0000FFFF), \ |
514 | bitswap(L, R, 2, 0x33333333), \ |
515 | bitswap(L, R, 8, 0x00FF00FF), \ |
516 | bitswap(R, L, 1, 0x55555555)) |
517 | |
518 | /* Final permutation */ |
519 | #define FP(L, R) (\ |
520 | bitswap(R, L, 1, 0x55555555), \ |
521 | bitswap(L, R, 8, 0x00FF00FF), \ |
522 | bitswap(L, R, 2, 0x33333333), \ |
523 | bitswap(R, L, 16, 0x0000FFFF), \ |
524 | bitswap(R, L, 4, 0x0F0F0F0F)) |
525 | |
526 | void des_encipher(word32 *output, word32 L, word32 R, DESContext *sched) { |
527 | word32 swap, s0246, s1357; |
528 | |
529 | IP(L, R); |
530 | |
531 | L = rotl(L, 1); |
532 | R = rotl(R, 1); |
533 | |
534 | L ^= f(R, sched->k0246[ 0], sched->k1357[ 0]); |
535 | R ^= f(L, sched->k0246[ 1], sched->k1357[ 1]); |
536 | L ^= f(R, sched->k0246[ 2], sched->k1357[ 2]); |
537 | R ^= f(L, sched->k0246[ 3], sched->k1357[ 3]); |
538 | L ^= f(R, sched->k0246[ 4], sched->k1357[ 4]); |
539 | R ^= f(L, sched->k0246[ 5], sched->k1357[ 5]); |
540 | L ^= f(R, sched->k0246[ 6], sched->k1357[ 6]); |
541 | R ^= f(L, sched->k0246[ 7], sched->k1357[ 7]); |
542 | L ^= f(R, sched->k0246[ 8], sched->k1357[ 8]); |
543 | R ^= f(L, sched->k0246[ 9], sched->k1357[ 9]); |
544 | L ^= f(R, sched->k0246[10], sched->k1357[10]); |
545 | R ^= f(L, sched->k0246[11], sched->k1357[11]); |
546 | L ^= f(R, sched->k0246[12], sched->k1357[12]); |
547 | R ^= f(L, sched->k0246[13], sched->k1357[13]); |
548 | L ^= f(R, sched->k0246[14], sched->k1357[14]); |
549 | R ^= f(L, sched->k0246[15], sched->k1357[15]); |
550 | |
551 | L = rotl(L, 31); |
552 | R = rotl(R, 31); |
553 | |
554 | swap = L; L = R; R = swap; |
555 | |
556 | FP(L, R); |
557 | |
558 | output[0] = L; |
559 | output[1] = R; |
560 | } |
374330e2 |
561 | |
d1e726bc |
562 | void des_decipher(word32 *output, word32 L, word32 R, DESContext *sched) { |
563 | word32 swap, s0246, s1357; |
374330e2 |
564 | |
d1e726bc |
565 | IP(L, R); |
374330e2 |
566 | |
d1e726bc |
567 | L = rotl(L, 1); |
568 | R = rotl(R, 1); |
374330e2 |
569 | |
d1e726bc |
570 | L ^= f(R, sched->k0246[15], sched->k1357[15]); |
571 | R ^= f(L, sched->k0246[14], sched->k1357[14]); |
572 | L ^= f(R, sched->k0246[13], sched->k1357[13]); |
573 | R ^= f(L, sched->k0246[12], sched->k1357[12]); |
574 | L ^= f(R, sched->k0246[11], sched->k1357[11]); |
575 | R ^= f(L, sched->k0246[10], sched->k1357[10]); |
576 | L ^= f(R, sched->k0246[ 9], sched->k1357[ 9]); |
577 | R ^= f(L, sched->k0246[ 8], sched->k1357[ 8]); |
578 | L ^= f(R, sched->k0246[ 7], sched->k1357[ 7]); |
579 | R ^= f(L, sched->k0246[ 6], sched->k1357[ 6]); |
580 | L ^= f(R, sched->k0246[ 5], sched->k1357[ 5]); |
581 | R ^= f(L, sched->k0246[ 4], sched->k1357[ 4]); |
582 | L ^= f(R, sched->k0246[ 3], sched->k1357[ 3]); |
583 | R ^= f(L, sched->k0246[ 2], sched->k1357[ 2]); |
584 | L ^= f(R, sched->k0246[ 1], sched->k1357[ 1]); |
585 | R ^= f(L, sched->k0246[ 0], sched->k1357[ 0]); |
586 | |
587 | L = rotl(L, 31); |
588 | R = rotl(R, 31); |
589 | |
590 | swap = L; L = R; R = swap; |
591 | |
592 | FP(L, R); |
593 | |
594 | output[0] = L; |
595 | output[1] = R; |
374330e2 |
596 | } |
597 | |
d1e726bc |
598 | #define GET_32BIT_MSB_FIRST(cp) \ |
599 | (((unsigned long)(unsigned char)(cp)[3]) | \ |
600 | ((unsigned long)(unsigned char)(cp)[2] << 8) | \ |
601 | ((unsigned long)(unsigned char)(cp)[1] << 16) | \ |
602 | ((unsigned long)(unsigned char)(cp)[0] << 24)) |
603 | |
604 | #define PUT_32BIT_MSB_FIRST(cp, value) do { \ |
605 | (cp)[3] = (value); \ |
606 | (cp)[2] = (value) >> 8; \ |
607 | (cp)[1] = (value) >> 16; \ |
608 | (cp)[0] = (value) >> 24; } while (0) |
609 | |
610 | static void des_cbc_encrypt(unsigned char *dest, const unsigned char *src, |
611 | unsigned int len, DESContext *sched) { |
612 | word32 out[2], iv0, iv1; |
613 | unsigned int i; |
614 | |
615 | assert((len & 7) == 0); |
616 | |
617 | iv0 = sched->eiv0; |
618 | iv1 = sched->eiv1; |
619 | for (i = 0; i < len; i += 8) { |
620 | iv0 ^= GET_32BIT_MSB_FIRST(src); src += 4; |
621 | iv1 ^= GET_32BIT_MSB_FIRST(src); src += 4; |
622 | des_encipher(out, iv0, iv1, sched); |
623 | iv0 = out[0]; |
624 | iv1 = out[1]; |
625 | PUT_32BIT_MSB_FIRST(dest, iv0); dest += 4; |
626 | PUT_32BIT_MSB_FIRST(dest, iv1); dest += 4; |
374330e2 |
627 | } |
d1e726bc |
628 | sched->eiv0 = iv0; |
629 | sched->eiv1 = iv1; |
374330e2 |
630 | } |
631 | |
d1e726bc |
632 | static void des_cbc_decrypt(unsigned char *dest, const unsigned char *src, |
633 | unsigned int len, DESContext *sched) { |
634 | word32 out[2], iv0, iv1, xL, xR; |
635 | unsigned int i; |
636 | |
637 | assert((len & 7) == 0); |
638 | |
639 | iv0 = sched->div0; |
640 | iv1 = sched->div1; |
641 | for (i = 0; i < len; i += 8) { |
642 | xL = GET_32BIT_MSB_FIRST(src); src += 4; |
643 | xR = GET_32BIT_MSB_FIRST(src); src += 4; |
644 | des_decipher(out, xL, xR, sched); |
645 | iv0 ^= out[0]; |
646 | iv1 ^= out[1]; |
647 | PUT_32BIT_MSB_FIRST(dest, iv0); dest += 4; |
648 | PUT_32BIT_MSB_FIRST(dest, iv1); dest += 4; |
649 | iv0 = xL; |
650 | iv1 = xR; |
374330e2 |
651 | } |
d1e726bc |
652 | sched->div0 = iv0; |
653 | sched->div1 = iv1; |
374330e2 |
654 | } |
655 | |
d1e726bc |
656 | static void des_3cbc_encrypt(unsigned char *dest, const unsigned char *src, |
657 | unsigned int len, DESContext *scheds) { |
658 | des_cbc_encrypt(dest, src, len, &scheds[0]); |
659 | des_cbc_decrypt(dest, src, len, &scheds[1]); |
660 | des_cbc_encrypt(dest, src, len, &scheds[2]); |
374330e2 |
661 | } |
662 | |
033b4cef |
663 | static void des_cbc3_encrypt(unsigned char *dest, const unsigned char *src, |
664 | unsigned int len, DESContext *scheds) { |
665 | word32 out[2], iv0, iv1; |
666 | unsigned int i; |
667 | |
668 | assert((len & 7) == 0); |
669 | |
670 | iv0 = scheds->eiv0; |
671 | iv1 = scheds->eiv1; |
672 | for (i = 0; i < len; i += 8) { |
673 | iv0 ^= GET_32BIT_MSB_FIRST(src); src += 4; |
674 | iv1 ^= GET_32BIT_MSB_FIRST(src); src += 4; |
675 | des_encipher(out, iv0, iv1, &scheds[0]); |
676 | des_decipher(out, out[0], out[1], &scheds[1]); |
677 | des_encipher(out, out[0], out[1], &scheds[2]); |
678 | iv0 = out[0]; |
679 | iv1 = out[1]; |
680 | PUT_32BIT_MSB_FIRST(dest, iv0); dest += 4; |
681 | PUT_32BIT_MSB_FIRST(dest, iv1); dest += 4; |
682 | } |
683 | scheds->eiv0 = iv0; |
684 | scheds->eiv1 = iv1; |
685 | } |
686 | |
d1e726bc |
687 | static void des_3cbc_decrypt(unsigned char *dest, const unsigned char *src, |
688 | unsigned int len, DESContext *scheds) { |
689 | des_cbc_decrypt(dest, src, len, &scheds[2]); |
690 | des_cbc_encrypt(dest, src, len, &scheds[1]); |
691 | des_cbc_decrypt(dest, src, len, &scheds[0]); |
374330e2 |
692 | } |
693 | |
033b4cef |
694 | static void des_cbc3_decrypt(unsigned char *dest, const unsigned char *src, |
695 | unsigned int len, DESContext *scheds) { |
696 | word32 out[2], iv0, iv1, xL, xR; |
697 | unsigned int i; |
698 | |
699 | assert((len & 7) == 0); |
700 | |
701 | iv0 = scheds->div0; |
702 | iv1 = scheds->div1; |
703 | for (i = 0; i < len; i += 8) { |
704 | xL = GET_32BIT_MSB_FIRST(src); src += 4; |
705 | xR = GET_32BIT_MSB_FIRST(src); src += 4; |
706 | des_decipher(out, xL, xR, &scheds[2]); |
707 | des_encipher(out, out[0], out[1], &scheds[1]); |
708 | des_decipher(out, out[0], out[1], &scheds[0]); |
709 | iv0 ^= out[0]; |
710 | iv1 ^= out[1]; |
711 | PUT_32BIT_MSB_FIRST(dest, iv0); dest += 4; |
712 | PUT_32BIT_MSB_FIRST(dest, iv1); dest += 4; |
713 | iv0 = xL; |
714 | iv1 = xR; |
715 | } |
716 | scheds->div0 = iv0; |
717 | scheds->div1 = iv1; |
718 | } |
719 | |
d39f364a |
720 | static DESContext cskeys[3], sckeys[3]; |
374330e2 |
721 | |
d39f364a |
722 | static void des3_cskey(unsigned char *key) { |
d1e726bc |
723 | des_key_setup(GET_32BIT_MSB_FIRST(key), |
d39f364a |
724 | GET_32BIT_MSB_FIRST(key+4), &cskeys[0]); |
d1e726bc |
725 | des_key_setup(GET_32BIT_MSB_FIRST(key+8), |
d39f364a |
726 | GET_32BIT_MSB_FIRST(key+12), &cskeys[1]); |
d1e726bc |
727 | des_key_setup(GET_32BIT_MSB_FIRST(key+16), |
d39f364a |
728 | GET_32BIT_MSB_FIRST(key+20), &cskeys[2]); |
729 | logevent("Initialised triple-DES client->server encryption"); |
730 | } |
731 | |
732 | static void des3_csiv(unsigned char *key) { |
733 | cskeys[0].eiv0 = GET_32BIT_MSB_FIRST(key); |
734 | cskeys[0].eiv1 = GET_32BIT_MSB_FIRST(key+4); |
735 | } |
736 | |
737 | static void des3_sciv(unsigned char *key) { |
738 | sckeys[0].div0 = GET_32BIT_MSB_FIRST(key); |
739 | sckeys[0].div1 = GET_32BIT_MSB_FIRST(key+4); |
740 | } |
741 | |
742 | static void des3_sckey(unsigned char *key) { |
743 | des_key_setup(GET_32BIT_MSB_FIRST(key), |
744 | GET_32BIT_MSB_FIRST(key+4), &sckeys[0]); |
745 | des_key_setup(GET_32BIT_MSB_FIRST(key+8), |
746 | GET_32BIT_MSB_FIRST(key+12), &sckeys[1]); |
747 | des_key_setup(GET_32BIT_MSB_FIRST(key+16), |
748 | GET_32BIT_MSB_FIRST(key+20), &sckeys[2]); |
749 | logevent("Initialised triple-DES server->client encryption"); |
750 | } |
751 | |
752 | static void des3_sesskey(unsigned char *key) { |
753 | des3_cskey(key); |
754 | des3_sckey(key); |
374330e2 |
755 | } |
756 | |
757 | static void des3_encrypt_blk(unsigned char *blk, int len) { |
d39f364a |
758 | des_3cbc_encrypt(blk, blk, len, cskeys); |
374330e2 |
759 | } |
760 | |
761 | static void des3_decrypt_blk(unsigned char *blk, int len) { |
d39f364a |
762 | des_3cbc_decrypt(blk, blk, len, sckeys); |
374330e2 |
763 | } |
764 | |
033b4cef |
765 | static void des3_ssh2_encrypt_blk(unsigned char *blk, int len) { |
766 | des_cbc3_encrypt(blk, blk, len, cskeys); |
767 | } |
768 | |
769 | static void des3_ssh2_decrypt_blk(unsigned char *blk, int len) { |
770 | des_cbc3_decrypt(blk, blk, len, sckeys); |
771 | } |
772 | |
7cca0d81 |
773 | void des3_decrypt_pubkey(unsigned char *key, |
774 | unsigned char *blk, int len) { |
775 | DESContext ourkeys[3]; |
776 | des_key_setup(GET_32BIT_MSB_FIRST(key), |
777 | GET_32BIT_MSB_FIRST(key+4), &ourkeys[0]); |
778 | des_key_setup(GET_32BIT_MSB_FIRST(key+8), |
779 | GET_32BIT_MSB_FIRST(key+12), &ourkeys[1]); |
780 | des_key_setup(GET_32BIT_MSB_FIRST(key), |
781 | GET_32BIT_MSB_FIRST(key+4), &ourkeys[2]); |
782 | des_3cbc_decrypt(blk, blk, len, ourkeys); |
783 | } |
784 | |
033b4cef |
785 | struct ssh_cipher ssh_3des_ssh2 = { |
786 | NULL, |
d39f364a |
787 | des3_csiv, des3_cskey, |
788 | des3_sciv, des3_sckey, |
033b4cef |
789 | des3_ssh2_encrypt_blk, |
790 | des3_ssh2_decrypt_blk, |
791 | "3des-cbc", |
792 | 8 |
793 | }; |
794 | |
795 | struct ssh_cipher ssh_3des = { |
796 | des3_sesskey, |
797 | NULL, NULL, NULL, NULL, |
374330e2 |
798 | des3_encrypt_blk, |
e5574168 |
799 | des3_decrypt_blk, |
800 | "3des-cbc", |
801 | 8 |
374330e2 |
802 | }; |
803 | |
9697bfd2 |
804 | static void des_sesskey(unsigned char *key) { |
d1e726bc |
805 | des_key_setup(GET_32BIT_MSB_FIRST(key), |
d39f364a |
806 | GET_32BIT_MSB_FIRST(key+4), &cskeys[0]); |
c5e9c988 |
807 | logevent("Initialised single-DES encryption"); |
9697bfd2 |
808 | } |
809 | |
810 | static void des_encrypt_blk(unsigned char *blk, int len) { |
d39f364a |
811 | des_cbc_encrypt(blk, blk, len, cskeys); |
9697bfd2 |
812 | } |
813 | |
814 | static void des_decrypt_blk(unsigned char *blk, int len) { |
d39f364a |
815 | des_cbc_decrypt(blk, blk, len, cskeys); |
9697bfd2 |
816 | } |
817 | |
818 | struct ssh_cipher ssh_des = { |
819 | des_sesskey, |
d39f364a |
820 | NULL, NULL, NULL, NULL, /* SSH 2 bits - unused */ |
9697bfd2 |
821 | des_encrypt_blk, |
e5574168 |
822 | des_decrypt_blk, |
823 | "des-cbc", /* should never be used - not a valid cipher in ssh2 */ |
824 | 8 |
9697bfd2 |
825 | }; |