File : g-sehamd.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT LIBRARY COMPONENTS --
4 -- --
5 -- G N A T . S E C U R E _ H A S H E S . M D 5 --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 2002-2009, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
17 -- --
18 -- --
19 -- --
20 -- --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
31
32 with GNAT.Byte_Swapping; use GNAT.Byte_Swapping;
33
34 package body GNAT.Secure_Hashes.MD5 is
35
36 use Interfaces;
37
38 -- The sixteen values used to rotate the context words. Four for each
39 -- rounds. Used in procedure Transform.
40
41 -- Round 1
42
43 S11 : constant := 7;
44 S12 : constant := 12;
45 S13 : constant := 17;
46 S14 : constant := 22;
47
48 -- Round 2
49
50 S21 : constant := 5;
51 S22 : constant := 9;
52 S23 : constant := 14;
53 S24 : constant := 20;
54
55 -- Round 3
56
57 S31 : constant := 4;
58 S32 : constant := 11;
59 S33 : constant := 16;
60 S34 : constant := 23;
61
62 -- Round 4
63
64 S41 : constant := 6;
65 S42 : constant := 10;
66 S43 : constant := 15;
67 S44 : constant := 21;
68
69 -- The following functions (F, FF, G, GG, H, HH, I and II) are the
70 -- equivalent of the macros of the same name in the example C
71 -- implementation in the annex of RFC 1321.
72
73 function F (X, Y, Z : Unsigned_32) return Unsigned_32;
74 pragma Inline (F);
75
76 procedure FF
77 (A : in out Unsigned_32;
78 B, C, D : Unsigned_32;
79 X : Unsigned_32;
80 AC : Unsigned_32;
81 S : Positive);
82 pragma Inline (FF);
83
84 function G (X, Y, Z : Unsigned_32) return Unsigned_32;
85 pragma Inline (G);
86
87 procedure GG
88 (A : in out Unsigned_32;
89 B, C, D : Unsigned_32;
90 X : Unsigned_32;
91 AC : Unsigned_32;
92 S : Positive);
93 pragma Inline (GG);
94
95 function H (X, Y, Z : Unsigned_32) return Unsigned_32;
96 pragma Inline (H);
97
98 procedure HH
99 (A : in out Unsigned_32;
100 B, C, D : Unsigned_32;
101 X : Unsigned_32;
102 AC : Unsigned_32;
103 S : Positive);
104 pragma Inline (HH);
105
106 function I (X, Y, Z : Unsigned_32) return Unsigned_32;
107 pragma Inline (I);
108
109 procedure II
110 (A : in out Unsigned_32;
111 B, C, D : Unsigned_32;
112 X : Unsigned_32;
113 AC : Unsigned_32;
114 S : Positive);
115 pragma Inline (II);
116
117 -------
118 -- F --
119 -------
120
121 function F (X, Y, Z : Unsigned_32) return Unsigned_32 is
122 begin
123 return (X and Y) or ((not X) and Z);
124 end F;
125
126 --------
127 -- FF --
128 --------
129
130 procedure FF
131 (A : in out Unsigned_32;
132 B, C, D : Unsigned_32;
133 X : Unsigned_32;
134 AC : Unsigned_32;
135 S : Positive)
136 is
137 begin
138 A := A + F (B, C, D) + X + AC;
139 A := Rotate_Left (A, S);
140 A := A + B;
141 end FF;
142
143 -------
144 -- G --
145 -------
146
147 function G (X, Y, Z : Unsigned_32) return Unsigned_32 is
148 begin
149 return (X and Z) or (Y and (not Z));
150 end G;
151
152 --------
153 -- GG --
154 --------
155
156 procedure GG
157 (A : in out Unsigned_32;
158 B, C, D : Unsigned_32;
159 X : Unsigned_32;
160 AC : Unsigned_32;
161 S : Positive)
162 is
163 begin
164 A := A + G (B, C, D) + X + AC;
165 A := Rotate_Left (A, S);
166 A := A + B;
167 end GG;
168
169 -------
170 -- H --
171 -------
172
173 function H (X, Y, Z : Unsigned_32) return Unsigned_32 is
174 begin
175 return X xor Y xor Z;
176 end H;
177
178 --------
179 -- HH --
180 --------
181
182 procedure HH
183 (A : in out Unsigned_32;
184 B, C, D : Unsigned_32;
185 X : Unsigned_32;
186 AC : Unsigned_32;
187 S : Positive)
188 is
189 begin
190 A := A + H (B, C, D) + X + AC;
191 A := Rotate_Left (A, S);
192 A := A + B;
193 end HH;
194
195 -------
196 -- I --
197 -------
198
199 function I (X, Y, Z : Unsigned_32) return Unsigned_32 is
200 begin
201 return Y xor (X or (not Z));
202 end I;
203
204 --------
205 -- II --
206 --------
207
208 procedure II
209 (A : in out Unsigned_32;
210 B, C, D : Unsigned_32;
211 X : Unsigned_32;
212 AC : Unsigned_32;
213 S : Positive)
214 is
215 begin
216 A := A + I (B, C, D) + X + AC;
217 A := Rotate_Left (A, S);
218 A := A + B;
219 end II;
220
221 ---------------
222 -- Transform --
223 ---------------
224
225 procedure Transform
226 (H : in out Hash_State.State;
227 M : in out Message_State)
228 is
229 use System;
230
231 X : array (0 .. 15) of Interfaces.Unsigned_32;
232 for X'Address use M.Buffer'Address;
233 pragma Import (Ada, X);
234
235 AA : Unsigned_32 := H (0);
236 BB : Unsigned_32 := H (1);
237 CC : Unsigned_32 := H (2);
238 DD : Unsigned_32 := H (3);
239
240 begin
241 if Default_Bit_Order /= Low_Order_First then
242 for J in X'Range loop
243 Swap4 (X (J)'Address);
244 end loop;
245 end if;
246
247 -- Round 1
248
249 FF (AA, BB, CC, DD, X (00), 16#D76aa478#, S11); -- 1
250 FF (DD, AA, BB, CC, X (01), 16#E8c7b756#, S12); -- 2
251 FF (CC, DD, AA, BB, X (02), 16#242070db#, S13); -- 3
252 FF (BB, CC, DD, AA, X (03), 16#C1bdceee#, S14); -- 4
253
254 FF (AA, BB, CC, DD, X (04), 16#f57c0faf#, S11); -- 5
255 FF (DD, AA, BB, CC, X (05), 16#4787c62a#, S12); -- 6
256 FF (CC, DD, AA, BB, X (06), 16#a8304613#, S13); -- 7
257 FF (BB, CC, DD, AA, X (07), 16#fd469501#, S14); -- 8
258
259 FF (AA, BB, CC, DD, X (08), 16#698098d8#, S11); -- 9
260 FF (DD, AA, BB, CC, X (09), 16#8b44f7af#, S12); -- 10
261 FF (CC, DD, AA, BB, X (10), 16#ffff5bb1#, S13); -- 11
262 FF (BB, CC, DD, AA, X (11), 16#895cd7be#, S14); -- 12
263
264 FF (AA, BB, CC, DD, X (12), 16#6b901122#, S11); -- 13
265 FF (DD, AA, BB, CC, X (13), 16#fd987193#, S12); -- 14
266 FF (CC, DD, AA, BB, X (14), 16#a679438e#, S13); -- 15
267 FF (BB, CC, DD, AA, X (15), 16#49b40821#, S14); -- 16
268
269 -- Round 2
270
271 GG (AA, BB, CC, DD, X (01), 16#f61e2562#, S21); -- 17
272 GG (DD, AA, BB, CC, X (06), 16#c040b340#, S22); -- 18
273 GG (CC, DD, AA, BB, X (11), 16#265e5a51#, S23); -- 19
274 GG (BB, CC, DD, AA, X (00), 16#e9b6c7aa#, S24); -- 20
275
276 GG (AA, BB, CC, DD, X (05), 16#d62f105d#, S21); -- 21
277 GG (DD, AA, BB, CC, X (10), 16#02441453#, S22); -- 22
278 GG (CC, DD, AA, BB, X (15), 16#d8a1e681#, S23); -- 23
279 GG (BB, CC, DD, AA, X (04), 16#e7d3fbc8#, S24); -- 24
280
281 GG (AA, BB, CC, DD, X (09), 16#21e1cde6#, S21); -- 25
282 GG (DD, AA, BB, CC, X (14), 16#c33707d6#, S22); -- 26
283 GG (CC, DD, AA, BB, X (03), 16#f4d50d87#, S23); -- 27
284 GG (BB, CC, DD, AA, X (08), 16#455a14ed#, S24); -- 28
285
286 GG (AA, BB, CC, DD, X (13), 16#a9e3e905#, S21); -- 29
287 GG (DD, AA, BB, CC, X (02), 16#fcefa3f8#, S22); -- 30
288 GG (CC, DD, AA, BB, X (07), 16#676f02d9#, S23); -- 31
289 GG (BB, CC, DD, AA, X (12), 16#8d2a4c8a#, S24); -- 32
290
291 -- Round 3
292
293 HH (AA, BB, CC, DD, X (05), 16#fffa3942#, S31); -- 33
294 HH (DD, AA, BB, CC, X (08), 16#8771f681#, S32); -- 34
295 HH (CC, DD, AA, BB, X (11), 16#6d9d6122#, S33); -- 35
296 HH (BB, CC, DD, AA, X (14), 16#fde5380c#, S34); -- 36
297
298 HH (AA, BB, CC, DD, X (01), 16#a4beea44#, S31); -- 37
299 HH (DD, AA, BB, CC, X (04), 16#4bdecfa9#, S32); -- 38
300 HH (CC, DD, AA, BB, X (07), 16#f6bb4b60#, S33); -- 39
301 HH (BB, CC, DD, AA, X (10), 16#bebfbc70#, S34); -- 40
302
303 HH (AA, BB, CC, DD, X (13), 16#289b7ec6#, S31); -- 41
304 HH (DD, AA, BB, CC, X (00), 16#eaa127fa#, S32); -- 42
305 HH (CC, DD, AA, BB, X (03), 16#d4ef3085#, S33); -- 43
306 HH (BB, CC, DD, AA, X (06), 16#04881d05#, S34); -- 44
307
308 HH (AA, BB, CC, DD, X (09), 16#d9d4d039#, S31); -- 45
309 HH (DD, AA, BB, CC, X (12), 16#e6db99e5#, S32); -- 46
310 HH (CC, DD, AA, BB, X (15), 16#1fa27cf8#, S33); -- 47
311 HH (BB, CC, DD, AA, X (02), 16#c4ac5665#, S34); -- 48
312
313 -- Round 4
314
315 II (AA, BB, CC, DD, X (00), 16#f4292244#, S41); -- 49
316 II (DD, AA, BB, CC, X (07), 16#432aff97#, S42); -- 50
317 II (CC, DD, AA, BB, X (14), 16#ab9423a7#, S43); -- 51
318 II (BB, CC, DD, AA, X (05), 16#fc93a039#, S44); -- 52
319
320 II (AA, BB, CC, DD, X (12), 16#655b59c3#, S41); -- 53
321 II (DD, AA, BB, CC, X (03), 16#8f0ccc92#, S42); -- 54
322 II (CC, DD, AA, BB, X (10), 16#ffeff47d#, S43); -- 55
323 II (BB, CC, DD, AA, X (01), 16#85845dd1#, S44); -- 56
324
325 II (AA, BB, CC, DD, X (08), 16#6fa87e4f#, S41); -- 57
326 II (DD, AA, BB, CC, X (15), 16#fe2ce6e0#, S42); -- 58
327 II (CC, DD, AA, BB, X (06), 16#a3014314#, S43); -- 59
328 II (BB, CC, DD, AA, X (13), 16#4e0811a1#, S44); -- 60
329
330 II (AA, BB, CC, DD, X (04), 16#f7537e82#, S41); -- 61
331 II (DD, AA, BB, CC, X (11), 16#bd3af235#, S42); -- 62
332 II (CC, DD, AA, BB, X (02), 16#2ad7d2bb#, S43); -- 63
333 II (BB, CC, DD, AA, X (09), 16#eb86d391#, S44); -- 64
334
335 H (0) := H (0) + AA;
336 H (1) := H (1) + BB;
337 H (2) := H (2) + CC;
338 H (3) := H (3) + DD;
339
340 end Transform;
341
342 end GNAT.Secure_Hashes.MD5;