bdes.ps

早期freebsd实现

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0.31 (Block Chaining, ) 72 712 P
3 F
0.31 (k) 154.25 712 P
0 F
0.31 (-bit Cipher Feed Back, and ) 159.58 712 P
3 F
0.31 (k) 293.71 712 P
0 F
0.31 (-bit Output Feed Back\051 as well as the Alternate ) 299.04 712 P
3 F
0.31 (k) 530.68 712 P
0 F
0.31 (-) 536.01 712 P
-0.04 (bit Cipher Feed Back mode. Further) 72 692 P
-0.04 (, ) 244.52 692 P
3 F
-0.04 (bdes) 250.48 692 P
0 F
-0.04 ( supports message authentication code generation based) 272.46 692 P
(on both the Cipher Block Chaining mode and the ) 72 672 T
3 F
(k) 310.86 672 T
0 F
(-bit Cipher Feed Back mode.) 316.19 672 T
0.07 (By default, ) 108 648 P
3 F
0.07 (bdes) 164.43 648 P
0 F
0.07 ( encrypts an input \336le using Cipher Block Chaining mode, and is invoked) 186.41 648 P
-0.4 (as a \336lter) 72 628 P
-0.4 (. The key may be speci\336ed either on the command line or may be typed to the prompt. So,) 114.51 628 P
(if the input \336le ) 72 608 T
7 F
(inputf) 145.96 608 T
(ile) 189.14 608 T
0 F
( contains the message) 210.73 608 T
6 F
(a) 253.9 584 T
8 F
(z) 261.1 584 T
6 F
(test) 266.07 584 T
8 F
(z) 294.86 584 T
6 F
(message) 299.83 584 T
9 F
(\277) 350.21 584 T
0 F
(then the following command encrypts it using the key ) 72 560 T
6 F
(abcdefgh) 333.5 560 T
0 F
(:) 391.07 560 T
6 F
(bdes -k abcdefgh < ) 158.48 536 T
7 F
(inputf) 295.21 536 T
(ile) 338.38 536 T
6 F
( > ) 359.97 536 T
7 F
(outputf) 381.56 536 T
(ile) 431.93 536 T
0 F
(The option ) 72 512 T
4 F
(-k) 127.3 512 T
0 F
( indicates the next ar) 137.96 512 T
(gument is the key) 237.01 512 T
(. Now ) 321.17 512 T
7 F
(outputf) 353.48 512 T
(ile) 403.86 512 T
0 F
( contains) 425.45 512 T
10 F
(16 0e eb af 68 a0 d0 19 f1 a2 9b 31 0d 8a 01 c3) 136.89 488 T
0 F
0.06 (Other modes are speci\336ed using command-line options, as is control of the way the key is) 108 464 P
(interpreted. The next sections contain several examples, and the Appendix has the manual page.) 72 444 T
4 F
(3. Keys and Parity) 72 412 T
0 F
0.58 (The key consists of 64 bits, and may be presented in any of hex, binary) 108 388 P
0.58 (, or as a string of) 456.48 388 P
5 F
0.12 (ASCII) 72 368 P
0 F
0.14 ( characters. If the key is given in hex or binary) 98.1 368 P
0.14 (, it is used as is with no changes. However) 322.21 368 P
0.14 (, if) 526.53 368 P
-0.27 (the key is given in ) 72 348 P
5 F
-0.23 (ASCII) 161.59 348 P
0 F
-0.27 (, a delicate problem arises: by convention, the parity bit is usually set to 0.) 187.69 348 P
-0.47 (This high-order bit is generally ignored by applications; but the DES
does not do so. Instead, it dis-) 72 328 P
-0.14 (cards the low-order bit, ef) 72 308 P
-0.14 (fectively reducing the size of the space of possible keys from 2) 195.44 308 P
5 F
-0.12 (56) 495.97 312.8 P
0 F
-0.14 ( to 2) 505.97 308 P
5 F
-0.12 (48) 527.01 312.8 P
0 F
-0.14 (.) 537 308 P
-0.46 ( T) 108 284 P
-0.46 (o preserve the size of the key space, the value of the parity bit must be related to the value) 117.03 284 P
-0.09 (in the low-order bit, so the program sets the high-order bit to make each character in the key be of) 72 264 P
-0.7 (odd parity) 72 244 P
-0.7 (. \050Note that the initial value of the parity bit is ) 119.49 244 P
3 F
-0.7 (not) 334.99 244 P
0 F
-0.7 ( used in this computation.\051 For example,) 350.31 244 P
(if the key is ) 72 224 T
6 F
(abcdefgh) 131.29 224 T
0 F
(, the actual key bits used are determined as follows:) 188.86 224 T
5 F
(ASCII) 99 200 T
0 F
( key) 125.1 200 T
6 F
(a) 243 200 T
(b) 279 200 T
(c) 315 200 T
(d) 351 200 T
(e) 387 200 T
(f) 423 200 T
(g) 459 200 T
(h) 495 200 T
5 F
(ASCII) 99 180 T
0 F
( key bits \050hex\051) 125.1 180 T
10 F
(61) 243 180 T
(62) 279 180 T
(63) 315 180 T
(64) 351 180 T
(65) 387 180 T
(66) 423 180 T
(67) 459 180 T
(68) 495 180 T
0 F
(parity) 99 160 T
(odd) 243 160 T
(odd) 279 160 T
(even) 315 160 T
(odd) 351 160 T
(even) 387 160 T
(even) 423 160 T
(odd) 459 160 T
(odd) 495 160 T
(key bits used \050hex\051) 99 140 T
10 F
(61) 243 140 T
(62) 279 140 T
(e3) 315 140 T
(64) 351 140 T
(e5) 387 140 T
(e6) 423 140 T
(67) 459 140 T
(68) 495 140 T
0 F
0.18 (This convention \050as opposed to requiring even parity) 108 120 P
0.18 (, or simply copying the low-order bit) 362 120 P
-0.41 (to the high-order bit\051 was chosen to provide compatibility with the encryption program ) 72 100 P
3 F
-0.41 (des) 486.77 100 P
0 F
-0.41 ( distrib-) 502.76 100 P
-0.52 (uted by Sun Microsystems, Inc. [4]. Whether the key is entered on the command line or on the key-) 72 80 P
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1.89 (board, by default it is processed into the same key schedule generated by Sun\325) 72 712 P
1.89 (s ) 471.02 712 P
3 F
1.89 (des) 480.58 712 P
0 F
1.89 (, so \336les) 496.56 712 P
(encrypted on a Sun can be decrypted using ) 72 692 T
3 F
(bdes) 280.51 692 T
0 F
( \050and vice versa\051.) 302.49 692 T
-0.3 (If the user does not wish to use the Sun convention, the option \320) 108 668 P
4 F
-0.3 (p) 411.9 668 P
0 F
-0.3 ( will disable the parity bit) 418.57 668 P
-0.62 (changing; with it, the parity bit is that of the character typed. This
is useful when the key is a known) 72 648 P
5 F
(ASCII) 72 628 T
0 F
( string and the \336le was encrypted on a system which does not alter parity bits.) 98.1 628 T
-0.24 (A key may be represented as a bit vector) 108 604 P
-0.24 (, rather than an ) 300.74 604 P
5 F
-0.2 (ASCII) 374.7 604 P
0 F
-0.24 ( string, in one of two ways. It) 400.8 604 P
0.19 (may be represented as a string of up to 16 hexadecimal digits; if fewer than 16 are given, the key) 72 584 P
0.16 (is right \336lled with 0 bits. Or) 72 564 P
0.16 (, it may be represented as a string of up to 64 binary digits, and again) 206.11 564 P
0.15 (if fewer than 64 are given, the key is right-\336lled with 0 bits. Bit
vector keys must be given on the) 72 544 P
0.51 (command line, and must begin with the characters ) 72 524 P
6 F
1.24 (0x) 320.28 524 P
0 F
0.51 ( or ) 334.67 524 P
6 F
1.24 (0X) 351.69 524 P
0 F
0.51 ( \050for hexadecimal\051 or ) 366.08 524 P
6 F
1.24 (0b) 472.71 524 P
0 F
0.51 ( or ) 487.1 524 P
6 F
1.24 (0B) 504.12 524 P
0 F
0.51 ( \050for) 518.51 524 P
(binary\051. For example, all of the following strings generate the same key schedule:) 72 504 T
5 F
(ASCII) 72 480 T
0 F
( key) 98.1 480 T
6 F
(abcdefgh) 180 480 T
0 F
(hexadecimal key) 72 460 T
6 F
(0x6162e364e5e66768) 180 460 T
0 F
(binary key) 72 440 T
6 F
(0b0110000101100010111000110110100011100101111000-) 180 440 T
(1100110011101101000) 180 420 T
0 F
-0.14 ( Note that giving the key on the command line as ) 108 396 P
6 F
-0.34 (0x6162636465666768) 345.27 396 P
0 F
-0.14 ( will ) 474.8 396 P
3 F
-0.14 (not) 499.17 396 P
0 F
-0.14 ( reset) 514.5 396 P
0.25 (the parity bits, because it is interpreted as a sequence of hex digits, not ) 72 376 P
5 F
0.21 (ASCII) 416.58 376 P
0 F
0.25 ( characters. The dif-) 442.68 376 P
0.69 (ference in interpretation is that here the user can specify all bits of the key exactly) 72 356 P
0.69 (, whereas \050on) 474.34 356 P
0.25 (most terminals\051 it is not possible to control how the parity bit of ) 72 336 P
5 F
0.21 (ASCII) 384.76 336 P
0 F
0.25 ( characters is set. On some) 410.85 336 P
0.36 (systems, it is possible to use a \322Meta\323 key to set the parity bit for an ) 72 316 P
5 F
0.3 (ASCII) 407.23 316 P
0 F
0.36 ( character; should this) 433.33 316 P
-0.3 (be the case and the user desire ) 72 296 P
3 F
-0.3 (bdes) 218.09 296 P
0 F
-0.3 ( not to reset the parity bit, the option ) 240.07 296 P
4 F
-0.3 (\320p) 415.25 296 P
0 F
-0.3 ( will force the parity bit) 427.92 296 P
(to be used as typed.) 72 276 T
4 F
(4. Encryption Output Repr) 72 244 T
(esentation) 211.05 244 T
0 F
0.01 (All modes of the DES output ciphertext in blocks; the size of the block is 64 bits \0508 bytes\051) 108 220 P
-0.25 (for ECB and CBC modes, and ) 72 200 P
3 F
-0.25 (k) 218.74 200 P
0 F
-0.25 ( bits for the ) 224.07 200 P
3 F
-0.25 (k) 281.02 200 P
0 F
-0.25 (-bit CFB and OFB modes, and there are as many out-) 286.35 200 P
-0.5 (put blocks as input blocks. However) 72 180 P
-0.5 (, as the length of the input is usually not a multiple of the block) 243.55 180 P
-0.35 (size, some padding is necessary; but as padding must be done by appending characters, these char-) 72 160 P
0.29 (acters must be distinguished from the input characters somehow) 72 140 P
0.29 (. The mechanism used is that the) 381.35 140 P
0.31 (last character of the \050decrypted\051 last block is the
\050integer\051 number of characters from the input in) 72 120 P
(the last block.) 72 100 T
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-0.59 (For example, suppose ) 108 712 P
7 F
-1.41 (inputf) 214.16 712 P
-1.41 (ile) 257.34 712 P
0 F
-0.59 ( contains \322) 278.93 712 P
6 F
-1.41 (This) 329.04 712 P
8 F
-0.65 (z) 357.83 712 P
6 F
-1.41 (is) 362.8 712 P
8 F
-0.65 (z) 377.2 712 P
6 F
-1.41 (a) 382.17 712 P
8 F
-0.65 (z) 389.37 712 P
6 F
-1.41 (test) 394.35 712 P
9 F
-0.59 (\277) 423.13 712 P
0 F
-0.59 (\323, and it is encrypted in) 431.02 712 P
(CBC mode using the key \322) 72 692 T
6 F
(abcdef#@) 200.93 692 T
0 F
(\323 and the initialization vector ) 258.5 692 T
6 F
(0x0) 401.4 692 T
0 F
(; the command is) 422.99 692 T
6 F
(bdes -k abcdef#@ < ) 158.48 668 T
7 F
(inputf) 295.21 668 T
(ile) 338.38 668 T
6 F
( > ) 359.97 668 T
7 F
(outputf) 381.56 668 T
(ile) 431.93 668 T
0 F
(as CBC is the default encryption mode and ) 72 644 T
6 F
(0x0) 281.2 644 T
0 F
( the default initialization vector:) 302.79 644 T
(text) 72 620 T
6 F
(T) 117 620 T
(h) 144 620 T
(i) 171 620 T
(s) 198 620 T
8 F
(z) 225 620 T
6 F
(i) 252 620 T
(s) 279 620 T
8 F
(z) 306 620 T
6 F
(a) 333 620 T
8 F
(z) 360 620 T
6 F
(t) 387 620 T
(e) 414 620 T
(s) 441 620 T
(t) 468 620 T
9 F
(\277) 495 620 T
0 F
(hex) 72 600 T
10 F
(54) 117 600 T
(68) 144 600 T
(69) 171 600 T
(73) 198 600 T
(20) 225 600 T
(69) 252 600 T
(73) 279 600 T
(20) 306 600 T
(61) 333 600 T
(20) 360 600 T
(74) 387 600 T
(65) 414 600 T
(73) 441 600 T
(74) 468 600 T
(0a) 495 600 T
0 F
(input) 72 580 T
10 F
(54) 117 580 T
(68) 144 580 T
(69) 171 580 T
(73) 198 580 T
(20) 225 580 T
(69) 252 580 T
(73) 279 580 T
(20) 306 580 T
(61) 333 580 T
(20) 360 580 T
(74) 387 580 T
(65) 414 580 T
(73) 441 580 T
(74) 468 580 T
(0a) 495 580 T
[phone] T
0 F
(output) 72 560 T
10 F
(a5) 117 560 T
(5f) 144 560 T
(81) 171 560 T
(53) 198 560 T
(51) 225 560 T
(98) 252 560 T
(47) 279 560 T
[phone] T
(db) 333 560 T
(5a) 360 560 T
(c5) 387 560 T
(fe) 414 560 T
(50) 441 560 T
(3d) 468 560 T
(40) 495 560 T
(ce) 522 560 T
0 F
0.04 (Notice that the text is 15 characters long, so there are 7 bytes following the last full block.) 108 540 P
3 F
0.22 (Bdes) 72 520 P
0 F
0.22 ( pads this to a full block by appending one byte containing the ) 95.32 520 P
5 F
0.19 (ASCII) 399.67 520 P
0 F
0.22 ( character with numeric) 425.77 520 P
(value 7 \050the ) 72 500 T
5 F
(ASCII) 131.62 500 T
0 F
( character <) 157.71 500 T
5 F
(BEL) 214.42 500 T
0 F
(>\051. The result is then encrypted.) 233.3 500 T
0.44 (As another example, suppose ) 108 476 P
7 F
1.07 (inputf) 253.34 476 P
1.07 (ile) 296.52 476 P
0 F
0.44 ( contains \322) 318.11 476 P
6 F
1.07 (test) 370.29 476 P
0 F
0.44 (\323, and it is encrypted in ECB) 399.08 476 P
(mode using the key \322) 72 456 T
6 F
(abcdef#@) 173.93 456 T
0 F
(\323; the command is) 231.5 456 T
6 F
(bdes -b \320k abcdef#@ < ) 147.69 432 T
7 F
(inputf) 306 432 T
(ile) 349.18 432 T
6 F
( > ) 370.76 432 T
7 F
(outputf) 392.35 432 T
(ile) 442.73 432 T
0 F
(because the option ) 72 408 T
4 F
(\320b) 164.26 408 T
0 F
( signi\336es ECB mode:) 176.93 408 T
(text) 72 384 T
6 F
(t) 144 384 T
(e) 171 384 T
(s) 198 384 T
(t) 225 384 T
0 F
(hex) 72 364 T
10 F
(74) 144 364 T
(65) 171 364 T
(73) 198 364 T
(74) 225 364 T
0 F
(input) 72 344 T
10 F
(74) 144 344 T
(65) 171 344 T
(73) 198 344 T
(74) 225 344 T
[phone] T
[phone] T
[phone] T
[phone] T
0 F
(output) 72 324 T
10 F
(0d) 144 324 T
(8a) 171 324 T