1 /* $OpenBSD: umac.c,v 1.11 2014/07/22 07:13:42 guenther Exp $ */
2 /* -----------------------------------------------------------------------
3  *
4  * umac.c -- C Implementation UMAC Message Authentication
5  *
6  * Version 0.93b of rfc4418.txt -- 2006 July 18
7  *
8  * For a full description of UMAC message authentication see the UMAC
9  * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac
10  * Please report bugs and suggestions to the UMAC webpage.
11  *
12  * Copyright (c) 1999-2006 Ted Krovetz
13  *
14  * Permission to use, copy, modify, and distribute this software and
15  * its documentation for any purpose and with or without fee, is hereby
16  * granted provided that the above copyright notice appears in all copies
17  * and in supporting documentation, and that the name of the copyright
18  * holder not be used in advertising or publicity pertaining to
19  * distribution of the software without specific, written prior permission.
20  *
21  * Comments should be directed to Ted Krovetz (tdk@acm.org)
22  *
23  * ---------------------------------------------------------------------- */
24 
25  /* ////////////////////// IMPORTANT NOTES /////////////////////////////////
26   *
27   * 1) This version does not work properly on messages larger than 16MB
28   *
29   * 2) If you set the switch to use SSE2, then all data must be 16-byte
30   *    aligned
31   *
32   * 3) When calling the function umac(), it is assumed that msg is in
33   * a writable buffer of length divisible by 32 bytes. The message itself
34   * does not have to fill the entire buffer, but bytes beyond msg may be
35   * zeroed.
36   *
37   * 4) Three free AES implementations are supported by this implementation of
38   * UMAC. Paulo Barreto's version is in the public domain and can be found
39   * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for
40   * "Barreto"). The only two files needed are rijndael-alg-fst.c and
41   * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU
42   * Public lisence at http://fp.gladman.plus.com/AES/index.htm. It
43   * includes a fast IA-32 assembly version. The OpenSSL crypo library is
44   * the third.
45   *
46   * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes
47   * produced under gcc with optimizations set -O3 or higher. Dunno why.
48   *
49   /////////////////////////////////////////////////////////////////////// */
50 
51 /* In OpenSSH, this file is compiled twice, with different #defines set on the
52  * command line. Since we don't want to stretch the Android build system, in
53  * Android this file is duplicated as umac.c and umac128.c. The latter contains
54  * the #defines (that were set in OpenSSH's Makefile) at the top of the
55  * file. */
56 
57 /* ---------------------------------------------------------------------- */
58 /* --- User Switches ---------------------------------------------------- */
59 /* ---------------------------------------------------------------------- */
60 
61 #ifndef UMAC_OUTPUT_LEN
62 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
63 #endif
64 
65 #if UMAC_OUTPUT_LEN != 4 && UMAC_OUTPUT_LEN != 8 && \
66     UMAC_OUTPUT_LEN != 12 && UMAC_OUTPUT_LEN != 16
67 # error UMAC_OUTPUT_LEN must be defined to 4, 8, 12 or 16
68 #endif
69 
70 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
71 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
72 /* #define SSE2                0  Is SSE2 is available?                   */
73 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
74 /* #define UMAC_AE_SUPPORT     0  Enable auhthenticated encrytion         */
75 
76 /* ---------------------------------------------------------------------- */
77 /* -- Global Includes --------------------------------------------------- */
78 /* ---------------------------------------------------------------------- */
79 
80 #include "includes.h"
81 #include <sys/types.h>
82 #include <string.h>
83 #include <stdio.h>
84 #include <stdlib.h>
85 #include <stddef.h>
86 
87 #include "xmalloc.h"
88 #include "umac.h"
89 #include "misc.h"
90 
91 /* ---------------------------------------------------------------------- */
92 /* --- Primitive Data Types ---                                           */
93 /* ---------------------------------------------------------------------- */
94 
95 /* The following assumptions may need change on your system */
96 typedef u_int8_t	UINT8;  /* 1 byte   */
97 typedef u_int16_t	UINT16; /* 2 byte   */
98 typedef u_int32_t	UINT32; /* 4 byte   */
99 typedef u_int64_t	UINT64; /* 8 bytes  */
100 typedef unsigned int	UWORD;  /* Register */
101 
102 /* ---------------------------------------------------------------------- */
103 /* --- Constants -------------------------------------------------------- */
104 /* ---------------------------------------------------------------------- */
105 
106 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
107 
108 /* Message "words" are read from memory in an endian-specific manner.     */
109 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
110 /* be set true if the host computer is little-endian.                     */
111 
112 #if BYTE_ORDER == LITTLE_ENDIAN
113 #define __LITTLE_ENDIAN__ 1
114 #else
115 #define __LITTLE_ENDIAN__ 0
116 #endif
117 
118 /* ---------------------------------------------------------------------- */
119 /* ---------------------------------------------------------------------- */
120 /* ----- Architecture Specific ------------------------------------------ */
121 /* ---------------------------------------------------------------------- */
122 /* ---------------------------------------------------------------------- */
123 
124 
125 /* ---------------------------------------------------------------------- */
126 /* ---------------------------------------------------------------------- */
127 /* ----- Primitive Routines --------------------------------------------- */
128 /* ---------------------------------------------------------------------- */
129 /* ---------------------------------------------------------------------- */
130 
131 
132 /* ---------------------------------------------------------------------- */
133 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
134 /* ---------------------------------------------------------------------- */
135 
136 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
137 
138 /* ---------------------------------------------------------------------- */
139 /* --- Endian Conversion --- Forcing assembly on some platforms           */
140 /* ---------------------------------------------------------------------- */
141 
142 #if (__LITTLE_ENDIAN__)
143 #define LOAD_UINT32_REVERSED(p)		get_u32(p)
144 #define STORE_UINT32_REVERSED(p,v)	put_u32(p,v)
145 #else
146 #define LOAD_UINT32_REVERSED(p)		get_u32_le(p)
147 #define STORE_UINT32_REVERSED(p,v)	put_u32_le(p,v)
148 #endif
149 
150 #define LOAD_UINT32_LITTLE(p)		(get_u32_le(p))
151 #define STORE_UINT32_BIG(p,v)		put_u32(p, v)
152 
153 /* ---------------------------------------------------------------------- */
154 /* ---------------------------------------------------------------------- */
155 /* ----- Begin KDF & PDF Section ---------------------------------------- */
156 /* ---------------------------------------------------------------------- */
157 /* ---------------------------------------------------------------------- */
158 
159 /* UMAC uses AES with 16 byte block and key lengths */
160 #define AES_BLOCK_LEN  16
161 
162 /* OpenSSL's AES */
163 #ifdef WITH_OPENSSL
164 #include "openbsd-compat/openssl-compat.h"
165 #ifndef USE_BUILTIN_RIJNDAEL
166 # include <openssl/aes.h>
167 #endif
168 typedef AES_KEY aes_int_key[1];
169 #define aes_encryption(in,out,int_key)                  \
170   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
171 #define aes_key_setup(key,int_key)                      \
172   AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key)
173 #else
174 #include "rijndael.h"
175 #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6)
176 typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4];	/* AES internal */
177 #define aes_encryption(in,out,int_key) \
178   rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out))
179 #define aes_key_setup(key,int_key) \
180   rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \
181   UMAC_KEY_LEN*8)
182 #endif
183 
184 /* The user-supplied UMAC key is stretched using AES in a counter
185  * mode to supply all random bits needed by UMAC. The kdf function takes
186  * an AES internal key representation 'key' and writes a stream of
187  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
188  * 'ndx' causes a distinct byte stream.
189  */
kdf(void * bufp,aes_int_key key,UINT8 ndx,int nbytes)190 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
191 {
192     UINT8 in_buf[AES_BLOCK_LEN] = {0};
193     UINT8 out_buf[AES_BLOCK_LEN];
194     UINT8 *dst_buf = (UINT8 *)bufp;
195     int i;
196 
197     /* Setup the initial value */
198     in_buf[AES_BLOCK_LEN-9] = ndx;
199     in_buf[AES_BLOCK_LEN-1] = i = 1;
200 
201     while (nbytes >= AES_BLOCK_LEN) {
202         aes_encryption(in_buf, out_buf, key);
203         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
204         in_buf[AES_BLOCK_LEN-1] = ++i;
205         nbytes -= AES_BLOCK_LEN;
206         dst_buf += AES_BLOCK_LEN;
207     }
208     if (nbytes) {
209         aes_encryption(in_buf, out_buf, key);
210         memcpy(dst_buf,out_buf,nbytes);
211     }
212 }
213 
214 /* The final UHASH result is XOR'd with the output of a pseudorandom
215  * function. Here, we use AES to generate random output and
216  * xor the appropriate bytes depending on the last bits of nonce.
217  * This scheme is optimized for sequential, increasing big-endian nonces.
218  */
219 
220 typedef struct {
221     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
222     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
223     aes_int_key prf_key;         /* Expanded AES key for PDF          */
224 } pdf_ctx;
225 
pdf_init(pdf_ctx * pc,aes_int_key prf_key)226 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
227 {
228     UINT8 buf[UMAC_KEY_LEN];
229 
230     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
231     aes_key_setup(buf, pc->prf_key);
232 
233     /* Initialize pdf and cache */
234     memset(pc->nonce, 0, sizeof(pc->nonce));
235     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
236 }
237 
pdf_gen_xor(pdf_ctx * pc,const UINT8 nonce[8],UINT8 buf[8])238 static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8])
239 {
240     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
241      * of the AES output. If last time around we returned the ndx-1st
242      * element, then we may have the result in the cache already.
243      */
244 
245 #if (UMAC_OUTPUT_LEN == 4)
246 #define LOW_BIT_MASK 3
247 #elif (UMAC_OUTPUT_LEN == 8)
248 #define LOW_BIT_MASK 1
249 #elif (UMAC_OUTPUT_LEN > 8)
250 #define LOW_BIT_MASK 0
251 #endif
252     union {
253         UINT8 tmp_nonce_lo[4];
254         UINT32 align;
255     } t;
256 #if LOW_BIT_MASK != 0
257     int ndx = nonce[7] & LOW_BIT_MASK;
258 #endif
259     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
260     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
261 
262     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
263          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
264     {
265         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
266         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
267         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
268     }
269 
270 #if (UMAC_OUTPUT_LEN == 4)
271     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
272 #elif (UMAC_OUTPUT_LEN == 8)
273     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
274 #elif (UMAC_OUTPUT_LEN == 12)
275     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
276     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
277 #elif (UMAC_OUTPUT_LEN == 16)
278     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
279     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
280 #endif
281 }
282 
283 /* ---------------------------------------------------------------------- */
284 /* ---------------------------------------------------------------------- */
285 /* ----- Begin NH Hash Section ------------------------------------------ */
286 /* ---------------------------------------------------------------------- */
287 /* ---------------------------------------------------------------------- */
288 
289 /* The NH-based hash functions used in UMAC are described in the UMAC paper
290  * and specification, both of which can be found at the UMAC website.
291  * The interface to this implementation has two
292  * versions, one expects the entire message being hashed to be passed
293  * in a single buffer and returns the hash result immediately. The second
294  * allows the message to be passed in a sequence of buffers. In the
295  * muliple-buffer interface, the client calls the routine nh_update() as
296  * many times as necessary. When there is no more data to be fed to the
297  * hash, the client calls nh_final() which calculates the hash output.
298  * Before beginning another hash calculation the nh_reset() routine
299  * must be called. The single-buffer routine, nh(), is equivalent to
300  * the sequence of calls nh_update() and nh_final(); however it is
301  * optimized and should be prefered whenever the multiple-buffer interface
302  * is not necessary. When using either interface, it is the client's
303  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
304  *
305  * The routine nh_init() initializes the nh_ctx data structure and
306  * must be called once, before any other PDF routine.
307  */
308 
309  /* The "nh_aux" routines do the actual NH hashing work. They
310   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
311   * produce output for all STREAMS NH iterations in one call,
312   * allowing the parallel implementation of the streams.
313   */
314 
315 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
316 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
317 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
318 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
319 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
320 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
321 
322 typedef struct {
323     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
324     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
325     int next_data_empty;    /* Bookeeping variable for data buffer.       */
326     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
327     UINT64 state[STREAMS];               /* on-line state     */
328 } nh_ctx;
329 
330 
331 #if (UMAC_OUTPUT_LEN == 4)
332 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)333 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
334 /* NH hashing primitive. Previous (partial) hash result is loaded and
335 * then stored via hp pointer. The length of the data pointed at by "dp",
336 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
337 * is expected to be endian compensated in memory at key setup.
338 */
339 {
340     UINT64 h;
341     UWORD c = dlen / 32;
342     UINT32 *k = (UINT32 *)kp;
343     const UINT32 *d = (const UINT32 *)dp;
344     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
345     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
346 
347     h = *((UINT64 *)hp);
348     do {
349         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
350         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
351         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
352         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
353         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
354         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
355         h += MUL64((k0 + d0), (k4 + d4));
356         h += MUL64((k1 + d1), (k5 + d5));
357         h += MUL64((k2 + d2), (k6 + d6));
358         h += MUL64((k3 + d3), (k7 + d7));
359 
360         d += 8;
361         k += 8;
362     } while (--c);
363   *((UINT64 *)hp) = h;
364 }
365 
366 #elif (UMAC_OUTPUT_LEN == 8)
367 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)368 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
369 /* Same as previous nh_aux, but two streams are handled in one pass,
370  * reading and writing 16 bytes of hash-state per call.
371  */
372 {
373   UINT64 h1,h2;
374   UWORD c = dlen / 32;
375   UINT32 *k = (UINT32 *)kp;
376   const UINT32 *d = (const UINT32 *)dp;
377   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
378   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
379         k8,k9,k10,k11;
380 
381   h1 = *((UINT64 *)hp);
382   h2 = *((UINT64 *)hp + 1);
383   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
384   do {
385     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
386     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
387     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
388     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
389     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
390     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
391 
392     h1 += MUL64((k0 + d0), (k4 + d4));
393     h2 += MUL64((k4 + d0), (k8 + d4));
394 
395     h1 += MUL64((k1 + d1), (k5 + d5));
396     h2 += MUL64((k5 + d1), (k9 + d5));
397 
398     h1 += MUL64((k2 + d2), (k6 + d6));
399     h2 += MUL64((k6 + d2), (k10 + d6));
400 
401     h1 += MUL64((k3 + d3), (k7 + d7));
402     h2 += MUL64((k7 + d3), (k11 + d7));
403 
404     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
405 
406     d += 8;
407     k += 8;
408   } while (--c);
409   ((UINT64 *)hp)[0] = h1;
410   ((UINT64 *)hp)[1] = h2;
411 }
412 
413 #elif (UMAC_OUTPUT_LEN == 12)
414 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)415 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
416 /* Same as previous nh_aux, but two streams are handled in one pass,
417  * reading and writing 24 bytes of hash-state per call.
418 */
419 {
420     UINT64 h1,h2,h3;
421     UWORD c = dlen / 32;
422     UINT32 *k = (UINT32 *)kp;
423     const UINT32 *d = (const UINT32 *)dp;
424     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
425     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
426         k8,k9,k10,k11,k12,k13,k14,k15;
427 
428     h1 = *((UINT64 *)hp);
429     h2 = *((UINT64 *)hp + 1);
430     h3 = *((UINT64 *)hp + 2);
431     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
432     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
433     do {
434         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
435         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
436         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
437         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
438         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
439         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
440 
441         h1 += MUL64((k0 + d0), (k4 + d4));
442         h2 += MUL64((k4 + d0), (k8 + d4));
443         h3 += MUL64((k8 + d0), (k12 + d4));
444 
445         h1 += MUL64((k1 + d1), (k5 + d5));
446         h2 += MUL64((k5 + d1), (k9 + d5));
447         h3 += MUL64((k9 + d1), (k13 + d5));
448 
449         h1 += MUL64((k2 + d2), (k6 + d6));
450         h2 += MUL64((k6 + d2), (k10 + d6));
451         h3 += MUL64((k10 + d2), (k14 + d6));
452 
453         h1 += MUL64((k3 + d3), (k7 + d7));
454         h2 += MUL64((k7 + d3), (k11 + d7));
455         h3 += MUL64((k11 + d3), (k15 + d7));
456 
457         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
458         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
459 
460         d += 8;
461         k += 8;
462     } while (--c);
463     ((UINT64 *)hp)[0] = h1;
464     ((UINT64 *)hp)[1] = h2;
465     ((UINT64 *)hp)[2] = h3;
466 }
467 
468 #elif (UMAC_OUTPUT_LEN == 16)
469 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)470 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
471 /* Same as previous nh_aux, but two streams are handled in one pass,
472  * reading and writing 24 bytes of hash-state per call.
473 */
474 {
475     UINT64 h1,h2,h3,h4;
476     UWORD c = dlen / 32;
477     UINT32 *k = (UINT32 *)kp;
478     const UINT32 *d = (const UINT32 *)dp;
479     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
480     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
481         k8,k9,k10,k11,k12,k13,k14,k15,
482         k16,k17,k18,k19;
483 
484     h1 = *((UINT64 *)hp);
485     h2 = *((UINT64 *)hp + 1);
486     h3 = *((UINT64 *)hp + 2);
487     h4 = *((UINT64 *)hp + 3);
488     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
489     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
490     do {
491         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
492         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
493         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
494         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
495         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
496         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
497         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
498 
499         h1 += MUL64((k0 + d0), (k4 + d4));
500         h2 += MUL64((k4 + d0), (k8 + d4));
501         h3 += MUL64((k8 + d0), (k12 + d4));
502         h4 += MUL64((k12 + d0), (k16 + d4));
503 
504         h1 += MUL64((k1 + d1), (k5 + d5));
505         h2 += MUL64((k5 + d1), (k9 + d5));
506         h3 += MUL64((k9 + d1), (k13 + d5));
507         h4 += MUL64((k13 + d1), (k17 + d5));
508 
509         h1 += MUL64((k2 + d2), (k6 + d6));
510         h2 += MUL64((k6 + d2), (k10 + d6));
511         h3 += MUL64((k10 + d2), (k14 + d6));
512         h4 += MUL64((k14 + d2), (k18 + d6));
513 
514         h1 += MUL64((k3 + d3), (k7 + d7));
515         h2 += MUL64((k7 + d3), (k11 + d7));
516         h3 += MUL64((k11 + d3), (k15 + d7));
517         h4 += MUL64((k15 + d3), (k19 + d7));
518 
519         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
520         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
521         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
522 
523         d += 8;
524         k += 8;
525     } while (--c);
526     ((UINT64 *)hp)[0] = h1;
527     ((UINT64 *)hp)[1] = h2;
528     ((UINT64 *)hp)[2] = h3;
529     ((UINT64 *)hp)[3] = h4;
530 }
531 
532 /* ---------------------------------------------------------------------- */
533 #endif  /* UMAC_OUTPUT_LENGTH */
534 /* ---------------------------------------------------------------------- */
535 
536 
537 /* ---------------------------------------------------------------------- */
538 
nh_transform(nh_ctx * hc,const UINT8 * buf,UINT32 nbytes)539 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
540 /* This function is a wrapper for the primitive NH hash functions. It takes
541  * as argument "hc" the current hash context and a buffer which must be a
542  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
543  * appropriately according to how much message has been hashed already.
544  */
545 {
546     UINT8 *key;
547 
548     key = hc->nh_key + hc->bytes_hashed;
549     nh_aux(key, buf, hc->state, nbytes);
550 }
551 
552 /* ---------------------------------------------------------------------- */
553 
554 #if (__LITTLE_ENDIAN__)
endian_convert(void * buf,UWORD bpw,UINT32 num_bytes)555 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
556 /* We endian convert the keys on little-endian computers to               */
557 /* compensate for the lack of big-endian memory reads during hashing.     */
558 {
559     UWORD iters = num_bytes / bpw;
560     if (bpw == 4) {
561         UINT32 *p = (UINT32 *)buf;
562         do {
563             *p = LOAD_UINT32_REVERSED(p);
564             p++;
565         } while (--iters);
566     } else if (bpw == 8) {
567         UINT32 *p = (UINT32 *)buf;
568         UINT32 t;
569         do {
570             t = LOAD_UINT32_REVERSED(p+1);
571             p[1] = LOAD_UINT32_REVERSED(p);
572             p[0] = t;
573             p += 2;
574         } while (--iters);
575     }
576 }
577 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
578 #else
579 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
580 #endif
581 
582 /* ---------------------------------------------------------------------- */
583 
nh_reset(nh_ctx * hc)584 static void nh_reset(nh_ctx *hc)
585 /* Reset nh_ctx to ready for hashing of new data */
586 {
587     hc->bytes_hashed = 0;
588     hc->next_data_empty = 0;
589     hc->state[0] = 0;
590 #if (UMAC_OUTPUT_LEN >= 8)
591     hc->state[1] = 0;
592 #endif
593 #if (UMAC_OUTPUT_LEN >= 12)
594     hc->state[2] = 0;
595 #endif
596 #if (UMAC_OUTPUT_LEN == 16)
597     hc->state[3] = 0;
598 #endif
599 
600 }
601 
602 /* ---------------------------------------------------------------------- */
603 
nh_init(nh_ctx * hc,aes_int_key prf_key)604 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
605 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
606 {
607     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
608     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
609     nh_reset(hc);
610 }
611 
612 /* ---------------------------------------------------------------------- */
613 
nh_update(nh_ctx * hc,const UINT8 * buf,UINT32 nbytes)614 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
615 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
616 /* even multiple of HASH_BUF_BYTES.                                       */
617 {
618     UINT32 i,j;
619 
620     j = hc->next_data_empty;
621     if ((j + nbytes) >= HASH_BUF_BYTES) {
622         if (j) {
623             i = HASH_BUF_BYTES - j;
624             memcpy(hc->data+j, buf, i);
625             nh_transform(hc,hc->data,HASH_BUF_BYTES);
626             nbytes -= i;
627             buf += i;
628             hc->bytes_hashed += HASH_BUF_BYTES;
629         }
630         if (nbytes >= HASH_BUF_BYTES) {
631             i = nbytes & ~(HASH_BUF_BYTES - 1);
632             nh_transform(hc, buf, i);
633             nbytes -= i;
634             buf += i;
635             hc->bytes_hashed += i;
636         }
637         j = 0;
638     }
639     memcpy(hc->data + j, buf, nbytes);
640     hc->next_data_empty = j + nbytes;
641 }
642 
643 /* ---------------------------------------------------------------------- */
644 
zero_pad(UINT8 * p,int nbytes)645 static void zero_pad(UINT8 *p, int nbytes)
646 {
647 /* Write "nbytes" of zeroes, beginning at "p" */
648     if (nbytes >= (int)sizeof(UWORD)) {
649         while ((ptrdiff_t)p % sizeof(UWORD)) {
650             *p = 0;
651             nbytes--;
652             p++;
653         }
654         while (nbytes >= (int)sizeof(UWORD)) {
655             *(UWORD *)p = 0;
656             nbytes -= sizeof(UWORD);
657             p += sizeof(UWORD);
658         }
659     }
660     while (nbytes) {
661         *p = 0;
662         nbytes--;
663         p++;
664     }
665 }
666 
667 /* ---------------------------------------------------------------------- */
668 
nh_final(nh_ctx * hc,UINT8 * result)669 static void nh_final(nh_ctx *hc, UINT8 *result)
670 /* After passing some number of data buffers to nh_update() for integration
671  * into an NH context, nh_final is called to produce a hash result. If any
672  * bytes are in the buffer hc->data, incorporate them into the
673  * NH context. Finally, add into the NH accumulation "state" the total number
674  * of bits hashed. The resulting numbers are written to the buffer "result".
675  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
676  */
677 {
678     int nh_len, nbits;
679 
680     if (hc->next_data_empty != 0) {
681         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
682                                                 ~(L1_PAD_BOUNDARY - 1));
683         zero_pad(hc->data + hc->next_data_empty,
684                                           nh_len - hc->next_data_empty);
685         nh_transform(hc, hc->data, nh_len);
686         hc->bytes_hashed += hc->next_data_empty;
687     } else if (hc->bytes_hashed == 0) {
688     	nh_len = L1_PAD_BOUNDARY;
689         zero_pad(hc->data, L1_PAD_BOUNDARY);
690         nh_transform(hc, hc->data, nh_len);
691     }
692 
693     nbits = (hc->bytes_hashed << 3);
694     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
695 #if (UMAC_OUTPUT_LEN >= 8)
696     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
697 #endif
698 #if (UMAC_OUTPUT_LEN >= 12)
699     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
700 #endif
701 #if (UMAC_OUTPUT_LEN == 16)
702     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
703 #endif
704     nh_reset(hc);
705 }
706 
707 /* ---------------------------------------------------------------------- */
708 
nh(nh_ctx * hc,const UINT8 * buf,UINT32 padded_len,UINT32 unpadded_len,UINT8 * result)709 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
710                UINT32 unpadded_len, UINT8 *result)
711 /* All-in-one nh_update() and nh_final() equivalent.
712  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
713  * well aligned
714  */
715 {
716     UINT32 nbits;
717 
718     /* Initialize the hash state */
719     nbits = (unpadded_len << 3);
720 
721     ((UINT64 *)result)[0] = nbits;
722 #if (UMAC_OUTPUT_LEN >= 8)
723     ((UINT64 *)result)[1] = nbits;
724 #endif
725 #if (UMAC_OUTPUT_LEN >= 12)
726     ((UINT64 *)result)[2] = nbits;
727 #endif
728 #if (UMAC_OUTPUT_LEN == 16)
729     ((UINT64 *)result)[3] = nbits;
730 #endif
731 
732     nh_aux(hc->nh_key, buf, result, padded_len);
733 }
734 
735 /* ---------------------------------------------------------------------- */
736 /* ---------------------------------------------------------------------- */
737 /* ----- Begin UHASH Section -------------------------------------------- */
738 /* ---------------------------------------------------------------------- */
739 /* ---------------------------------------------------------------------- */
740 
741 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
742  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
743  * unless the initial data to be hashed is short. After the polynomial-
744  * layer, an inner-product hash is used to produce the final UHASH output.
745  *
746  * UHASH provides two interfaces, one all-at-once and another where data
747  * buffers are presented sequentially. In the sequential interface, the
748  * UHASH client calls the routine uhash_update() as many times as necessary.
749  * When there is no more data to be fed to UHASH, the client calls
750  * uhash_final() which
751  * calculates the UHASH output. Before beginning another UHASH calculation
752  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
753  * uhash(), is equivalent to the sequence of calls uhash_update() and
754  * uhash_final(); however it is optimized and should be
755  * used whenever the sequential interface is not necessary.
756  *
757  * The routine uhash_init() initializes the uhash_ctx data structure and
758  * must be called once, before any other UHASH routine.
759  */
760 
761 /* ---------------------------------------------------------------------- */
762 /* ----- Constants and uhash_ctx ---------------------------------------- */
763 /* ---------------------------------------------------------------------- */
764 
765 /* ---------------------------------------------------------------------- */
766 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
767 /* ---------------------------------------------------------------------- */
768 
769 /* Primes and masks */
770 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
771 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
772 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
773 
774 
775 /* ---------------------------------------------------------------------- */
776 
777 typedef struct uhash_ctx {
778     nh_ctx hash;                          /* Hash context for L1 NH hash  */
779     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
780     UINT64 poly_accum[STREAMS];           /* poly hash result             */
781     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
782     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
783     UINT32 msg_len;                       /* Total length of data passed  */
784                                           /* to uhash */
785 } uhash_ctx;
786 typedef struct uhash_ctx *uhash_ctx_t;
787 
788 /* ---------------------------------------------------------------------- */
789 
790 
791 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
792  * word at a time. As described in the specification, poly32 and poly64
793  * require keys from special domains. The following implementations exploit
794  * the special domains to avoid overflow. The results are not guaranteed to
795  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
796  * patches any errant values.
797  */
798 
poly64(UINT64 cur,UINT64 key,UINT64 data)799 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
800 {
801     UINT32 key_hi = (UINT32)(key >> 32),
802            key_lo = (UINT32)key,
803            cur_hi = (UINT32)(cur >> 32),
804            cur_lo = (UINT32)cur,
805            x_lo,
806            x_hi;
807     UINT64 X,T,res;
808 
809     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
810     x_lo = (UINT32)X;
811     x_hi = (UINT32)(X >> 32);
812 
813     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
814 
815     T = ((UINT64)x_lo << 32);
816     res += T;
817     if (res < T)
818         res += 59;
819 
820     res += data;
821     if (res < data)
822         res += 59;
823 
824     return res;
825 }
826 
827 
828 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
829  * implementation does not handle all ramp levels. Because we don't handle
830  * the ramp up to p128 modulus in this implementation, we are limited to
831  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
832  * bytes input to UMAC per tag, ie. 16MB).
833  */
poly_hash(uhash_ctx_t hc,UINT32 data_in[])834 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
835 {
836     int i;
837     UINT64 *data=(UINT64*)data_in;
838 
839     for (i = 0; i < STREAMS; i++) {
840         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
841             hc->poly_accum[i] = poly64(hc->poly_accum[i],
842                                        hc->poly_key_8[i], p64 - 1);
843             hc->poly_accum[i] = poly64(hc->poly_accum[i],
844                                        hc->poly_key_8[i], (data[i] - 59));
845         } else {
846             hc->poly_accum[i] = poly64(hc->poly_accum[i],
847                                        hc->poly_key_8[i], data[i]);
848         }
849     }
850 }
851 
852 
853 /* ---------------------------------------------------------------------- */
854 
855 
856 /* The final step in UHASH is an inner-product hash. The poly hash
857  * produces a result not neccesarily WORD_LEN bytes long. The inner-
858  * product hash breaks the polyhash output into 16-bit chunks and
859  * multiplies each with a 36 bit key.
860  */
861 
ip_aux(UINT64 t,UINT64 * ipkp,UINT64 data)862 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
863 {
864     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
865     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
866     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
867     t = t + ipkp[3] * (UINT64)(UINT16)(data);
868 
869     return t;
870 }
871 
ip_reduce_p36(UINT64 t)872 static UINT32 ip_reduce_p36(UINT64 t)
873 {
874 /* Divisionless modular reduction */
875     UINT64 ret;
876 
877     ret = (t & m36) + 5 * (t >> 36);
878     if (ret >= p36)
879         ret -= p36;
880 
881     /* return least significant 32 bits */
882     return (UINT32)(ret);
883 }
884 
885 
886 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
887  * the polyhash stage is skipped and ip_short is applied directly to the
888  * NH output.
889  */
ip_short(uhash_ctx_t ahc,UINT8 * nh_res,u_char * res)890 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
891 {
892     UINT64 t;
893     UINT64 *nhp = (UINT64 *)nh_res;
894 
895     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
896     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
897 #if (UMAC_OUTPUT_LEN >= 8)
898     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
899     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
900 #endif
901 #if (UMAC_OUTPUT_LEN >= 12)
902     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
903     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
904 #endif
905 #if (UMAC_OUTPUT_LEN == 16)
906     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
907     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
908 #endif
909 }
910 
911 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
912  * the polyhash stage is not skipped and ip_long is applied to the
913  * polyhash output.
914  */
ip_long(uhash_ctx_t ahc,u_char * res)915 static void ip_long(uhash_ctx_t ahc, u_char *res)
916 {
917     int i;
918     UINT64 t;
919 
920     for (i = 0; i < STREAMS; i++) {
921         /* fix polyhash output not in Z_p64 */
922         if (ahc->poly_accum[i] >= p64)
923             ahc->poly_accum[i] -= p64;
924         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
925         STORE_UINT32_BIG((UINT32 *)res+i,
926                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
927     }
928 }
929 
930 
931 /* ---------------------------------------------------------------------- */
932 
933 /* ---------------------------------------------------------------------- */
934 
935 /* Reset uhash context for next hash session */
uhash_reset(uhash_ctx_t pc)936 static int uhash_reset(uhash_ctx_t pc)
937 {
938     nh_reset(&pc->hash);
939     pc->msg_len = 0;
940     pc->poly_accum[0] = 1;
941 #if (UMAC_OUTPUT_LEN >= 8)
942     pc->poly_accum[1] = 1;
943 #endif
944 #if (UMAC_OUTPUT_LEN >= 12)
945     pc->poly_accum[2] = 1;
946 #endif
947 #if (UMAC_OUTPUT_LEN == 16)
948     pc->poly_accum[3] = 1;
949 #endif
950     return 1;
951 }
952 
953 /* ---------------------------------------------------------------------- */
954 
955 /* Given a pointer to the internal key needed by kdf() and a uhash context,
956  * initialize the NH context and generate keys needed for poly and inner-
957  * product hashing. All keys are endian adjusted in memory so that native
958  * loads cause correct keys to be in registers during calculation.
959  */
uhash_init(uhash_ctx_t ahc,aes_int_key prf_key)960 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
961 {
962     int i;
963     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
964 
965     /* Zero the entire uhash context */
966     memset(ahc, 0, sizeof(uhash_ctx));
967 
968     /* Initialize the L1 hash */
969     nh_init(&ahc->hash, prf_key);
970 
971     /* Setup L2 hash variables */
972     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
973     for (i = 0; i < STREAMS; i++) {
974         /* Fill keys from the buffer, skipping bytes in the buffer not
975          * used by this implementation. Endian reverse the keys if on a
976          * little-endian computer.
977          */
978         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
979         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
980         /* Mask the 64-bit keys to their special domain */
981         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
982         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
983     }
984 
985     /* Setup L3-1 hash variables */
986     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
987     for (i = 0; i < STREAMS; i++)
988           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
989                                                  4*sizeof(UINT64));
990     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
991                                                   sizeof(ahc->ip_keys));
992     for (i = 0; i < STREAMS*4; i++)
993         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
994 
995     /* Setup L3-2 hash variables    */
996     /* Fill buffer with index 4 key */
997     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
998     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
999                          STREAMS * sizeof(UINT32));
1000 }
1001 
1002 /* ---------------------------------------------------------------------- */
1003 
1004 #if 0
1005 static uhash_ctx_t uhash_alloc(u_char key[])
1006 {
1007 /* Allocate memory and force to a 16-byte boundary. */
1008     uhash_ctx_t ctx;
1009     u_char bytes_to_add;
1010     aes_int_key prf_key;
1011 
1012     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1013     if (ctx) {
1014         if (ALLOC_BOUNDARY) {
1015             bytes_to_add = ALLOC_BOUNDARY -
1016                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1017             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1018             *((u_char *)ctx - 1) = bytes_to_add;
1019         }
1020         aes_key_setup(key,prf_key);
1021         uhash_init(ctx, prf_key);
1022     }
1023     return (ctx);
1024 }
1025 #endif
1026 
1027 /* ---------------------------------------------------------------------- */
1028 
1029 #if 0
1030 static int uhash_free(uhash_ctx_t ctx)
1031 {
1032 /* Free memory allocated by uhash_alloc */
1033     u_char bytes_to_sub;
1034 
1035     if (ctx) {
1036         if (ALLOC_BOUNDARY) {
1037             bytes_to_sub = *((u_char *)ctx - 1);
1038             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1039         }
1040         free(ctx);
1041     }
1042     return (1);
1043 }
1044 #endif
1045 /* ---------------------------------------------------------------------- */
1046 
uhash_update(uhash_ctx_t ctx,const u_char * input,long len)1047 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1048 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1049  * hash each one with NH, calling the polyhash on each NH output.
1050  */
1051 {
1052     UWORD bytes_hashed, bytes_remaining;
1053     UINT64 result_buf[STREAMS];
1054     UINT8 *nh_result = (UINT8 *)&result_buf;
1055 
1056     if (ctx->msg_len + len <= L1_KEY_LEN) {
1057         nh_update(&ctx->hash, (const UINT8 *)input, len);
1058         ctx->msg_len += len;
1059     } else {
1060 
1061          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1062          if (ctx->msg_len == L1_KEY_LEN)
1063              bytes_hashed = L1_KEY_LEN;
1064 
1065          if (bytes_hashed + len >= L1_KEY_LEN) {
1066 
1067              /* If some bytes have been passed to the hash function      */
1068              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1069              /* bytes to complete the current nh_block.                  */
1070              if (bytes_hashed) {
1071                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1072                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1073                  nh_final(&ctx->hash, nh_result);
1074                  ctx->msg_len += bytes_remaining;
1075                  poly_hash(ctx,(UINT32 *)nh_result);
1076                  len -= bytes_remaining;
1077                  input += bytes_remaining;
1078              }
1079 
1080              /* Hash directly from input stream if enough bytes */
1081              while (len >= L1_KEY_LEN) {
1082                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1083                                    L1_KEY_LEN, nh_result);
1084                  ctx->msg_len += L1_KEY_LEN;
1085                  len -= L1_KEY_LEN;
1086                  input += L1_KEY_LEN;
1087                  poly_hash(ctx,(UINT32 *)nh_result);
1088              }
1089          }
1090 
1091          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1092          if (len) {
1093              nh_update(&ctx->hash, (const UINT8 *)input, len);
1094              ctx->msg_len += len;
1095          }
1096      }
1097 
1098     return (1);
1099 }
1100 
1101 /* ---------------------------------------------------------------------- */
1102 
uhash_final(uhash_ctx_t ctx,u_char * res)1103 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1104 /* Incorporate any pending data, pad, and generate tag */
1105 {
1106     UINT64 result_buf[STREAMS];
1107     UINT8 *nh_result = (UINT8 *)&result_buf;
1108 
1109     if (ctx->msg_len > L1_KEY_LEN) {
1110         if (ctx->msg_len % L1_KEY_LEN) {
1111             nh_final(&ctx->hash, nh_result);
1112             poly_hash(ctx,(UINT32 *)nh_result);
1113         }
1114         ip_long(ctx, res);
1115     } else {
1116         nh_final(&ctx->hash, nh_result);
1117         ip_short(ctx,nh_result, res);
1118     }
1119     uhash_reset(ctx);
1120     return (1);
1121 }
1122 
1123 /* ---------------------------------------------------------------------- */
1124 
1125 #if 0
1126 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1127 /* assumes that msg is in a writable buffer of length divisible by */
1128 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1129 {
1130     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1131     UINT32 nh_len;
1132     int extra_zeroes_needed;
1133 
1134     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1135      * the polyhash.
1136      */
1137     if (len <= L1_KEY_LEN) {
1138     	if (len == 0)                  /* If zero length messages will not */
1139     		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1140     	else
1141         	nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1142         extra_zeroes_needed = nh_len - len;
1143         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1144         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1145         ip_short(ahc,nh_result, res);
1146     } else {
1147         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1148          * output to poly_hash().
1149          */
1150         do {
1151             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1152             poly_hash(ahc,(UINT32 *)nh_result);
1153             len -= L1_KEY_LEN;
1154             msg += L1_KEY_LEN;
1155         } while (len >= L1_KEY_LEN);
1156         if (len) {
1157             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1158             extra_zeroes_needed = nh_len - len;
1159             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1160             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1161             poly_hash(ahc,(UINT32 *)nh_result);
1162         }
1163 
1164         ip_long(ahc, res);
1165     }
1166 
1167     uhash_reset(ahc);
1168     return 1;
1169 }
1170 #endif
1171 
1172 /* ---------------------------------------------------------------------- */
1173 /* ---------------------------------------------------------------------- */
1174 /* ----- Begin UMAC Section --------------------------------------------- */
1175 /* ---------------------------------------------------------------------- */
1176 /* ---------------------------------------------------------------------- */
1177 
1178 /* The UMAC interface has two interfaces, an all-at-once interface where
1179  * the entire message to be authenticated is passed to UMAC in one buffer,
1180  * and a sequential interface where the message is presented a little at a
1181  * time. The all-at-once is more optimaized than the sequential version and
1182  * should be preferred when the sequential interface is not required.
1183  */
1184 struct umac_ctx {
1185     uhash_ctx hash;          /* Hash function for message compression    */
1186     pdf_ctx pdf;             /* PDF for hashed output                    */
1187     void *free_ptr;          /* Address to free this struct via          */
1188 } umac_ctx;
1189 
1190 /* ---------------------------------------------------------------------- */
1191 
1192 #if 0
1193 int umac_reset(struct umac_ctx *ctx)
1194 /* Reset the hash function to begin a new authentication.        */
1195 {
1196     uhash_reset(&ctx->hash);
1197     return (1);
1198 }
1199 #endif
1200 
1201 /* ---------------------------------------------------------------------- */
1202 
umac_delete(struct umac_ctx * ctx)1203 int umac_delete(struct umac_ctx *ctx)
1204 /* Deallocate the ctx structure */
1205 {
1206     if (ctx) {
1207         if (ALLOC_BOUNDARY)
1208             ctx = (struct umac_ctx *)ctx->free_ptr;
1209         free(ctx);
1210     }
1211     return (1);
1212 }
1213 
1214 /* ---------------------------------------------------------------------- */
1215 
umac_new(const u_char key[])1216 struct umac_ctx *umac_new(const u_char key[])
1217 /* Dynamically allocate a umac_ctx struct, initialize variables,
1218  * generate subkeys from key. Align to 16-byte boundary.
1219  */
1220 {
1221     struct umac_ctx *ctx, *octx;
1222     size_t bytes_to_add;
1223     aes_int_key prf_key;
1224 
1225     octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1226     if (ctx) {
1227         if (ALLOC_BOUNDARY) {
1228             bytes_to_add = ALLOC_BOUNDARY -
1229                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1230             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1231         }
1232         ctx->free_ptr = octx;
1233         aes_key_setup(key, prf_key);
1234         pdf_init(&ctx->pdf, prf_key);
1235         uhash_init(&ctx->hash, prf_key);
1236     }
1237 
1238     return (ctx);
1239 }
1240 
1241 /* ---------------------------------------------------------------------- */
1242 
umac_final(struct umac_ctx * ctx,u_char tag[],const u_char nonce[8])1243 int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1244 /* Incorporate any pending data, pad, and generate tag */
1245 {
1246     uhash_final(&ctx->hash, (u_char *)tag);
1247     pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1248 
1249     return (1);
1250 }
1251 
1252 /* ---------------------------------------------------------------------- */
1253 
umac_update(struct umac_ctx * ctx,const u_char * input,long len)1254 int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1255 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1256 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1257 /* output buffer is full.                                                 */
1258 {
1259     uhash_update(&ctx->hash, input, len);
1260     return (1);
1261 }
1262 
1263 /* ---------------------------------------------------------------------- */
1264 
1265 #if 0
1266 int umac(struct umac_ctx *ctx, u_char *input,
1267          long len, u_char tag[],
1268          u_char nonce[8])
1269 /* All-in-one version simply calls umac_update() and umac_final().        */
1270 {
1271     uhash(&ctx->hash, input, len, (u_char *)tag);
1272     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1273 
1274     return (1);
1275 }
1276 #endif
1277 
1278 /* ---------------------------------------------------------------------- */
1279 /* ---------------------------------------------------------------------- */
1280 /* ----- End UMAC Section ----------------------------------------------- */
1281 /* ---------------------------------------------------------------------- */
1282 /* ---------------------------------------------------------------------- */
1283