xref: /openbsd/usr.bin/ssh/umac.c (revision 5af055cd)
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 /* ---------------------------------------------------------------------- */
52 /* --- User Switches ---------------------------------------------------- */
53 /* ---------------------------------------------------------------------- */
54 
55 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
56 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
57 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
58 /* #define SSE2                0  Is SSE2 is available?                   */
59 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
60 /* #define UMAC_AE_SUPPORT     0  Enable auhthenticated encrytion         */
61 
62 /* ---------------------------------------------------------------------- */
63 /* -- Global Includes --------------------------------------------------- */
64 /* ---------------------------------------------------------------------- */
65 
66 #include <sys/types.h>
67 #include <endian.h>
68 #include <string.h>
69 #include <stdio.h>
70 #include <stdlib.h>
71 #include <stddef.h>
72 
73 #include "xmalloc.h"
74 #include "umac.h"
75 #include "misc.h"
76 
77 /* ---------------------------------------------------------------------- */
78 /* --- Primitive Data Types ---                                           */
79 /* ---------------------------------------------------------------------- */
80 
81 /* The following assumptions may need change on your system */
82 typedef u_int8_t	UINT8;  /* 1 byte   */
83 typedef u_int16_t	UINT16; /* 2 byte   */
84 typedef u_int32_t	UINT32; /* 4 byte   */
85 typedef u_int64_t	UINT64; /* 8 bytes  */
86 typedef unsigned int	UWORD;  /* Register */
87 
88 /* ---------------------------------------------------------------------- */
89 /* --- Constants -------------------------------------------------------- */
90 /* ---------------------------------------------------------------------- */
91 
92 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
93 
94 /* Message "words" are read from memory in an endian-specific manner.     */
95 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
96 /* be set true if the host computer is little-endian.                     */
97 
98 #if BYTE_ORDER == LITTLE_ENDIAN
99 #define __LITTLE_ENDIAN__ 1
100 #else
101 #define __LITTLE_ENDIAN__ 0
102 #endif
103 
104 /* ---------------------------------------------------------------------- */
105 /* ---------------------------------------------------------------------- */
106 /* ----- Architecture Specific ------------------------------------------ */
107 /* ---------------------------------------------------------------------- */
108 /* ---------------------------------------------------------------------- */
109 
110 
111 /* ---------------------------------------------------------------------- */
112 /* ---------------------------------------------------------------------- */
113 /* ----- Primitive Routines --------------------------------------------- */
114 /* ---------------------------------------------------------------------- */
115 /* ---------------------------------------------------------------------- */
116 
117 
118 /* ---------------------------------------------------------------------- */
119 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
120 /* ---------------------------------------------------------------------- */
121 
122 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
123 
124 /* ---------------------------------------------------------------------- */
125 /* --- Endian Conversion --- Forcing assembly on some platforms           */
126 /* ---------------------------------------------------------------------- */
127 
128 /* The following definitions use the above reversal-primitives to do the right
129  * thing on endian specific load and stores.
130  */
131 
132 #if BYTE_ORDER == LITTLE_ENDIAN
133 #define LOAD_UINT32_REVERSED(p)		get_u32(p)
134 #define STORE_UINT32_REVERSED(p,v) 	put_u32(p,v)
135 #else
136 #define LOAD_UINT32_REVERSED(p)		get_u32_le(p)
137 #define STORE_UINT32_REVERSED(p,v) 	put_u32_le(p,v)
138 #endif
139 
140 #define LOAD_UINT32_LITTLE(p)           (get_u32_le(p))
141 #define STORE_UINT32_BIG(p,v)           put_u32(p, v)
142 
143 
144 
145 /* ---------------------------------------------------------------------- */
146 /* ---------------------------------------------------------------------- */
147 /* ----- Begin KDF & PDF Section ---------------------------------------- */
148 /* ---------------------------------------------------------------------- */
149 /* ---------------------------------------------------------------------- */
150 
151 /* UMAC uses AES with 16 byte block and key lengths */
152 #define AES_BLOCK_LEN  16
153 
154 #ifdef WITH_OPENSSL
155 #include <openssl/aes.h>
156 typedef AES_KEY aes_int_key[1];
157 #define aes_encryption(in,out,int_key)                  \
158   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
159 #define aes_key_setup(key,int_key)                      \
160   AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key)
161 #else
162 #include "rijndael.h"
163 #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6)
164 typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4];	/* AES internal */
165 #define aes_encryption(in,out,int_key) \
166   rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out))
167 #define aes_key_setup(key,int_key) \
168   rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \
169   UMAC_KEY_LEN*8)
170 #endif
171 
172 /* The user-supplied UMAC key is stretched using AES in a counter
173  * mode to supply all random bits needed by UMAC. The kdf function takes
174  * an AES internal key representation 'key' and writes a stream of
175  * 'nbytes' bytes to the memory pointed at by 'buffer_ptr'. Each distinct
176  * 'ndx' causes a distinct byte stream.
177  */
178 static void kdf(void *buffer_ptr, aes_int_key key, UINT8 ndx, int nbytes)
179 {
180     UINT8 in_buf[AES_BLOCK_LEN] = {0};
181     UINT8 out_buf[AES_BLOCK_LEN];
182     UINT8 *dst_buf = (UINT8 *)buffer_ptr;
183     int i;
184 
185     /* Setup the initial value */
186     in_buf[AES_BLOCK_LEN-9] = ndx;
187     in_buf[AES_BLOCK_LEN-1] = i = 1;
188 
189     while (nbytes >= AES_BLOCK_LEN) {
190         aes_encryption(in_buf, out_buf, key);
191         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
192         in_buf[AES_BLOCK_LEN-1] = ++i;
193         nbytes -= AES_BLOCK_LEN;
194         dst_buf += AES_BLOCK_LEN;
195     }
196     if (nbytes) {
197         aes_encryption(in_buf, out_buf, key);
198         memcpy(dst_buf,out_buf,nbytes);
199     }
200 }
201 
202 /* The final UHASH result is XOR'd with the output of a pseudorandom
203  * function. Here, we use AES to generate random output and
204  * xor the appropriate bytes depending on the last bits of nonce.
205  * This scheme is optimized for sequential, increasing big-endian nonces.
206  */
207 
208 typedef struct {
209     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
210     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
211     aes_int_key prf_key;         /* Expanded AES key for PDF          */
212 } pdf_ctx;
213 
214 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
215 {
216     UINT8 buf[UMAC_KEY_LEN];
217 
218     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
219     aes_key_setup(buf, pc->prf_key);
220 
221     /* Initialize pdf and cache */
222     memset(pc->nonce, 0, sizeof(pc->nonce));
223     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
224 }
225 
226 static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8])
227 {
228     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
229      * of the AES output. If last time around we returned the ndx-1st
230      * element, then we may have the result in the cache already.
231      */
232 
233 #if (UMAC_OUTPUT_LEN == 4)
234 #define LOW_BIT_MASK 3
235 #elif (UMAC_OUTPUT_LEN == 8)
236 #define LOW_BIT_MASK 1
237 #elif (UMAC_OUTPUT_LEN > 8)
238 #define LOW_BIT_MASK 0
239 #endif
240     union {
241         UINT8 tmp_nonce_lo[4];
242         UINT32 align;
243     } t;
244 #if LOW_BIT_MASK != 0
245     int ndx = nonce[7] & LOW_BIT_MASK;
246 #endif
247     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
248     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
249 
250     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
251          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
252     {
253         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
254         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
255         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
256     }
257 
258 #if (UMAC_OUTPUT_LEN == 4)
259     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
260 #elif (UMAC_OUTPUT_LEN == 8)
261     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
262 #elif (UMAC_OUTPUT_LEN == 12)
263     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
264     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
265 #elif (UMAC_OUTPUT_LEN == 16)
266     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
267     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
268 #endif
269 }
270 
271 /* ---------------------------------------------------------------------- */
272 /* ---------------------------------------------------------------------- */
273 /* ----- Begin NH Hash Section ------------------------------------------ */
274 /* ---------------------------------------------------------------------- */
275 /* ---------------------------------------------------------------------- */
276 
277 /* The NH-based hash functions used in UMAC are described in the UMAC paper
278  * and specification, both of which can be found at the UMAC website.
279  * The interface to this implementation has two
280  * versions, one expects the entire message being hashed to be passed
281  * in a single buffer and returns the hash result immediately. The second
282  * allows the message to be passed in a sequence of buffers. In the
283  * muliple-buffer interface, the client calls the routine nh_update() as
284  * many times as necessary. When there is no more data to be fed to the
285  * hash, the client calls nh_final() which calculates the hash output.
286  * Before beginning another hash calculation the nh_reset() routine
287  * must be called. The single-buffer routine, nh(), is equivalent to
288  * the sequence of calls nh_update() and nh_final(); however it is
289  * optimized and should be prefered whenever the multiple-buffer interface
290  * is not necessary. When using either interface, it is the client's
291  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
292  *
293  * The routine nh_init() initializes the nh_ctx data structure and
294  * must be called once, before any other PDF routine.
295  */
296 
297  /* The "nh_aux" routines do the actual NH hashing work. They
298   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
299   * produce output for all STREAMS NH iterations in one call,
300   * allowing the parallel implementation of the streams.
301   */
302 
303 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
304 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
305 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
306 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
307 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
308 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
309 
310 typedef struct {
311     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
312     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
313     int next_data_empty;    /* Bookeeping variable for data buffer.       */
314     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
315     UINT64 state[STREAMS];               /* on-line state     */
316 } nh_ctx;
317 
318 
319 #if (UMAC_OUTPUT_LEN == 4)
320 
321 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
322 /* NH hashing primitive. Previous (partial) hash result is loaded and
323 * then stored via hp pointer. The length of the data pointed at by "dp",
324 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
325 * is expected to be endian compensated in memory at key setup.
326 */
327 {
328     UINT64 h;
329     UWORD c = dlen / 32;
330     UINT32 *k = (UINT32 *)kp;
331     const UINT32 *d = (const UINT32 *)dp;
332     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
333     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
334 
335     h = *((UINT64 *)hp);
336     do {
337         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
338         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
339         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
340         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
341         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
342         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
343         h += MUL64((k0 + d0), (k4 + d4));
344         h += MUL64((k1 + d1), (k5 + d5));
345         h += MUL64((k2 + d2), (k6 + d6));
346         h += MUL64((k3 + d3), (k7 + d7));
347 
348         d += 8;
349         k += 8;
350     } while (--c);
351   *((UINT64 *)hp) = h;
352 }
353 
354 #elif (UMAC_OUTPUT_LEN == 8)
355 
356 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
357 /* Same as previous nh_aux, but two streams are handled in one pass,
358  * reading and writing 16 bytes of hash-state per call.
359  */
360 {
361   UINT64 h1,h2;
362   UWORD c = dlen / 32;
363   UINT32 *k = (UINT32 *)kp;
364   const UINT32 *d = (const UINT32 *)dp;
365   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
366   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
367         k8,k9,k10,k11;
368 
369   h1 = *((UINT64 *)hp);
370   h2 = *((UINT64 *)hp + 1);
371   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
372   do {
373     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
374     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
375     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
376     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
377     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
378     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
379 
380     h1 += MUL64((k0 + d0), (k4 + d4));
381     h2 += MUL64((k4 + d0), (k8 + d4));
382 
383     h1 += MUL64((k1 + d1), (k5 + d5));
384     h2 += MUL64((k5 + d1), (k9 + d5));
385 
386     h1 += MUL64((k2 + d2), (k6 + d6));
387     h2 += MUL64((k6 + d2), (k10 + d6));
388 
389     h1 += MUL64((k3 + d3), (k7 + d7));
390     h2 += MUL64((k7 + d3), (k11 + d7));
391 
392     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
393 
394     d += 8;
395     k += 8;
396   } while (--c);
397   ((UINT64 *)hp)[0] = h1;
398   ((UINT64 *)hp)[1] = h2;
399 }
400 
401 #elif (UMAC_OUTPUT_LEN == 12)
402 
403 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
404 /* Same as previous nh_aux, but two streams are handled in one pass,
405  * reading and writing 24 bytes of hash-state per call.
406 */
407 {
408     UINT64 h1,h2,h3;
409     UWORD c = dlen / 32;
410     UINT32 *k = (UINT32 *)kp;
411     const UINT32 *d = (const UINT32 *)dp;
412     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
413     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
414         k8,k9,k10,k11,k12,k13,k14,k15;
415 
416     h1 = *((UINT64 *)hp);
417     h2 = *((UINT64 *)hp + 1);
418     h3 = *((UINT64 *)hp + 2);
419     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
420     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
421     do {
422         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
423         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
424         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
425         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
426         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
427         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
428 
429         h1 += MUL64((k0 + d0), (k4 + d4));
430         h2 += MUL64((k4 + d0), (k8 + d4));
431         h3 += MUL64((k8 + d0), (k12 + d4));
432 
433         h1 += MUL64((k1 + d1), (k5 + d5));
434         h2 += MUL64((k5 + d1), (k9 + d5));
435         h3 += MUL64((k9 + d1), (k13 + d5));
436 
437         h1 += MUL64((k2 + d2), (k6 + d6));
438         h2 += MUL64((k6 + d2), (k10 + d6));
439         h3 += MUL64((k10 + d2), (k14 + d6));
440 
441         h1 += MUL64((k3 + d3), (k7 + d7));
442         h2 += MUL64((k7 + d3), (k11 + d7));
443         h3 += MUL64((k11 + d3), (k15 + d7));
444 
445         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
446         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
447 
448         d += 8;
449         k += 8;
450     } while (--c);
451     ((UINT64 *)hp)[0] = h1;
452     ((UINT64 *)hp)[1] = h2;
453     ((UINT64 *)hp)[2] = h3;
454 }
455 
456 #elif (UMAC_OUTPUT_LEN == 16)
457 
458 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
459 /* Same as previous nh_aux, but two streams are handled in one pass,
460  * reading and writing 24 bytes of hash-state per call.
461 */
462 {
463     UINT64 h1,h2,h3,h4;
464     UWORD c = dlen / 32;
465     UINT32 *k = (UINT32 *)kp;
466     const UINT32 *d = (const UINT32 *)dp;
467     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
468     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
469         k8,k9,k10,k11,k12,k13,k14,k15,
470         k16,k17,k18,k19;
471 
472     h1 = *((UINT64 *)hp);
473     h2 = *((UINT64 *)hp + 1);
474     h3 = *((UINT64 *)hp + 2);
475     h4 = *((UINT64 *)hp + 3);
476     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
477     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
478     do {
479         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
480         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
481         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
482         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
483         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
484         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
485         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
486 
487         h1 += MUL64((k0 + d0), (k4 + d4));
488         h2 += MUL64((k4 + d0), (k8 + d4));
489         h3 += MUL64((k8 + d0), (k12 + d4));
490         h4 += MUL64((k12 + d0), (k16 + d4));
491 
492         h1 += MUL64((k1 + d1), (k5 + d5));
493         h2 += MUL64((k5 + d1), (k9 + d5));
494         h3 += MUL64((k9 + d1), (k13 + d5));
495         h4 += MUL64((k13 + d1), (k17 + d5));
496 
497         h1 += MUL64((k2 + d2), (k6 + d6));
498         h2 += MUL64((k6 + d2), (k10 + d6));
499         h3 += MUL64((k10 + d2), (k14 + d6));
500         h4 += MUL64((k14 + d2), (k18 + d6));
501 
502         h1 += MUL64((k3 + d3), (k7 + d7));
503         h2 += MUL64((k7 + d3), (k11 + d7));
504         h3 += MUL64((k11 + d3), (k15 + d7));
505         h4 += MUL64((k15 + d3), (k19 + d7));
506 
507         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
508         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
509         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
510 
511         d += 8;
512         k += 8;
513     } while (--c);
514     ((UINT64 *)hp)[0] = h1;
515     ((UINT64 *)hp)[1] = h2;
516     ((UINT64 *)hp)[2] = h3;
517     ((UINT64 *)hp)[3] = h4;
518 }
519 
520 /* ---------------------------------------------------------------------- */
521 #endif  /* UMAC_OUTPUT_LENGTH */
522 /* ---------------------------------------------------------------------- */
523 
524 
525 /* ---------------------------------------------------------------------- */
526 
527 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
528 /* This function is a wrapper for the primitive NH hash functions. It takes
529  * as argument "hc" the current hash context and a buffer which must be a
530  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
531  * appropriately according to how much message has been hashed already.
532  */
533 {
534     UINT8 *key;
535 
536     key = hc->nh_key + hc->bytes_hashed;
537     nh_aux(key, buf, hc->state, nbytes);
538 }
539 
540 /* ---------------------------------------------------------------------- */
541 
542 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
543 /* We endian convert the keys on little-endian computers to               */
544 /* compensate for the lack of big-endian memory reads during hashing.     */
545 {
546     UWORD iters = num_bytes / bpw;
547     if (bpw == 4) {
548         UINT32 *p = (UINT32 *)buf;
549         do {
550             *p = LOAD_UINT32_REVERSED(p);
551             p++;
552         } while (--iters);
553     } else if (bpw == 8) {
554         UINT32 *p = (UINT32 *)buf;
555         UINT32 t;
556         do {
557             t = LOAD_UINT32_REVERSED(p+1);
558             p[1] = LOAD_UINT32_REVERSED(p);
559             p[0] = t;
560             p += 2;
561         } while (--iters);
562     }
563 }
564 #if (__LITTLE_ENDIAN__)
565 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
566 #else
567 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
568 #endif
569 
570 /* ---------------------------------------------------------------------- */
571 
572 static void nh_reset(nh_ctx *hc)
573 /* Reset nh_ctx to ready for hashing of new data */
574 {
575     hc->bytes_hashed = 0;
576     hc->next_data_empty = 0;
577     hc->state[0] = 0;
578 #if (UMAC_OUTPUT_LEN >= 8)
579     hc->state[1] = 0;
580 #endif
581 #if (UMAC_OUTPUT_LEN >= 12)
582     hc->state[2] = 0;
583 #endif
584 #if (UMAC_OUTPUT_LEN == 16)
585     hc->state[3] = 0;
586 #endif
587 
588 }
589 
590 /* ---------------------------------------------------------------------- */
591 
592 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
593 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
594 {
595     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
596     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
597     nh_reset(hc);
598 }
599 
600 /* ---------------------------------------------------------------------- */
601 
602 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
603 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
604 /* even multiple of HASH_BUF_BYTES.                                       */
605 {
606     UINT32 i,j;
607 
608     j = hc->next_data_empty;
609     if ((j + nbytes) >= HASH_BUF_BYTES) {
610         if (j) {
611             i = HASH_BUF_BYTES - j;
612             memcpy(hc->data+j, buf, i);
613             nh_transform(hc,hc->data,HASH_BUF_BYTES);
614             nbytes -= i;
615             buf += i;
616             hc->bytes_hashed += HASH_BUF_BYTES;
617         }
618         if (nbytes >= HASH_BUF_BYTES) {
619             i = nbytes & ~(HASH_BUF_BYTES - 1);
620             nh_transform(hc, buf, i);
621             nbytes -= i;
622             buf += i;
623             hc->bytes_hashed += i;
624         }
625         j = 0;
626     }
627     memcpy(hc->data + j, buf, nbytes);
628     hc->next_data_empty = j + nbytes;
629 }
630 
631 /* ---------------------------------------------------------------------- */
632 
633 static void zero_pad(UINT8 *p, int nbytes)
634 {
635 /* Write "nbytes" of zeroes, beginning at "p" */
636     if (nbytes >= (int)sizeof(UWORD)) {
637         while ((ptrdiff_t)p % sizeof(UWORD)) {
638             *p = 0;
639             nbytes--;
640             p++;
641         }
642         while (nbytes >= (int)sizeof(UWORD)) {
643             *(UWORD *)p = 0;
644             nbytes -= sizeof(UWORD);
645             p += sizeof(UWORD);
646         }
647     }
648     while (nbytes) {
649         *p = 0;
650         nbytes--;
651         p++;
652     }
653 }
654 
655 /* ---------------------------------------------------------------------- */
656 
657 static void nh_final(nh_ctx *hc, UINT8 *result)
658 /* After passing some number of data buffers to nh_update() for integration
659  * into an NH context, nh_final is called to produce a hash result. If any
660  * bytes are in the buffer hc->data, incorporate them into the
661  * NH context. Finally, add into the NH accumulation "state" the total number
662  * of bits hashed. The resulting numbers are written to the buffer "result".
663  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
664  */
665 {
666     int nh_len, nbits;
667 
668     if (hc->next_data_empty != 0) {
669         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
670                                                 ~(L1_PAD_BOUNDARY - 1));
671         zero_pad(hc->data + hc->next_data_empty,
672                                           nh_len - hc->next_data_empty);
673         nh_transform(hc, hc->data, nh_len);
674         hc->bytes_hashed += hc->next_data_empty;
675     } else if (hc->bytes_hashed == 0) {
676     	nh_len = L1_PAD_BOUNDARY;
677         zero_pad(hc->data, L1_PAD_BOUNDARY);
678         nh_transform(hc, hc->data, nh_len);
679     }
680 
681     nbits = (hc->bytes_hashed << 3);
682     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
683 #if (UMAC_OUTPUT_LEN >= 8)
684     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
685 #endif
686 #if (UMAC_OUTPUT_LEN >= 12)
687     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
688 #endif
689 #if (UMAC_OUTPUT_LEN == 16)
690     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
691 #endif
692     nh_reset(hc);
693 }
694 
695 /* ---------------------------------------------------------------------- */
696 
697 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
698                UINT32 unpadded_len, UINT8 *result)
699 /* All-in-one nh_update() and nh_final() equivalent.
700  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
701  * well aligned
702  */
703 {
704     UINT32 nbits;
705 
706     /* Initialize the hash state */
707     nbits = (unpadded_len << 3);
708 
709     ((UINT64 *)result)[0] = nbits;
710 #if (UMAC_OUTPUT_LEN >= 8)
711     ((UINT64 *)result)[1] = nbits;
712 #endif
713 #if (UMAC_OUTPUT_LEN >= 12)
714     ((UINT64 *)result)[2] = nbits;
715 #endif
716 #if (UMAC_OUTPUT_LEN == 16)
717     ((UINT64 *)result)[3] = nbits;
718 #endif
719 
720     nh_aux(hc->nh_key, buf, result, padded_len);
721 }
722 
723 /* ---------------------------------------------------------------------- */
724 /* ---------------------------------------------------------------------- */
725 /* ----- Begin UHASH Section -------------------------------------------- */
726 /* ---------------------------------------------------------------------- */
727 /* ---------------------------------------------------------------------- */
728 
729 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
730  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
731  * unless the initial data to be hashed is short. After the polynomial-
732  * layer, an inner-product hash is used to produce the final UHASH output.
733  *
734  * UHASH provides two interfaces, one all-at-once and another where data
735  * buffers are presented sequentially. In the sequential interface, the
736  * UHASH client calls the routine uhash_update() as many times as necessary.
737  * When there is no more data to be fed to UHASH, the client calls
738  * uhash_final() which
739  * calculates the UHASH output. Before beginning another UHASH calculation
740  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
741  * uhash(), is equivalent to the sequence of calls uhash_update() and
742  * uhash_final(); however it is optimized and should be
743  * used whenever the sequential interface is not necessary.
744  *
745  * The routine uhash_init() initializes the uhash_ctx data structure and
746  * must be called once, before any other UHASH routine.
747  */
748 
749 /* ---------------------------------------------------------------------- */
750 /* ----- Constants and uhash_ctx ---------------------------------------- */
751 /* ---------------------------------------------------------------------- */
752 
753 /* ---------------------------------------------------------------------- */
754 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
755 /* ---------------------------------------------------------------------- */
756 
757 /* Primes and masks */
758 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
759 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
760 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
761 
762 
763 /* ---------------------------------------------------------------------- */
764 
765 typedef struct uhash_ctx {
766     nh_ctx hash;                          /* Hash context for L1 NH hash  */
767     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
768     UINT64 poly_accum[STREAMS];           /* poly hash result             */
769     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
770     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
771     UINT32 msg_len;                       /* Total length of data passed  */
772                                           /* to uhash */
773 } uhash_ctx;
774 typedef struct uhash_ctx *uhash_ctx_t;
775 
776 /* ---------------------------------------------------------------------- */
777 
778 
779 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
780  * word at a time. As described in the specification, poly32 and poly64
781  * require keys from special domains. The following implementations exploit
782  * the special domains to avoid overflow. The results are not guaranteed to
783  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
784  * patches any errant values.
785  */
786 
787 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
788 {
789     UINT32 key_hi = (UINT32)(key >> 32),
790            key_lo = (UINT32)key,
791            cur_hi = (UINT32)(cur >> 32),
792            cur_lo = (UINT32)cur,
793            x_lo,
794            x_hi;
795     UINT64 X,T,res;
796 
797     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
798     x_lo = (UINT32)X;
799     x_hi = (UINT32)(X >> 32);
800 
801     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
802 
803     T = ((UINT64)x_lo << 32);
804     res += T;
805     if (res < T)
806         res += 59;
807 
808     res += data;
809     if (res < data)
810         res += 59;
811 
812     return res;
813 }
814 
815 
816 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
817  * implementation does not handle all ramp levels. Because we don't handle
818  * the ramp up to p128 modulus in this implementation, we are limited to
819  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
820  * bytes input to UMAC per tag, ie. 16MB).
821  */
822 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
823 {
824     int i;
825     UINT64 *data=(UINT64*)data_in;
826 
827     for (i = 0; i < STREAMS; i++) {
828         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
829             hc->poly_accum[i] = poly64(hc->poly_accum[i],
830                                        hc->poly_key_8[i], p64 - 1);
831             hc->poly_accum[i] = poly64(hc->poly_accum[i],
832                                        hc->poly_key_8[i], (data[i] - 59));
833         } else {
834             hc->poly_accum[i] = poly64(hc->poly_accum[i],
835                                        hc->poly_key_8[i], data[i]);
836         }
837     }
838 }
839 
840 
841 /* ---------------------------------------------------------------------- */
842 
843 
844 /* The final step in UHASH is an inner-product hash. The poly hash
845  * produces a result not neccesarily WORD_LEN bytes long. The inner-
846  * product hash breaks the polyhash output into 16-bit chunks and
847  * multiplies each with a 36 bit key.
848  */
849 
850 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
851 {
852     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
853     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
854     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
855     t = t + ipkp[3] * (UINT64)(UINT16)(data);
856 
857     return t;
858 }
859 
860 static UINT32 ip_reduce_p36(UINT64 t)
861 {
862 /* Divisionless modular reduction */
863     UINT64 ret;
864 
865     ret = (t & m36) + 5 * (t >> 36);
866     if (ret >= p36)
867         ret -= p36;
868 
869     /* return least significant 32 bits */
870     return (UINT32)(ret);
871 }
872 
873 
874 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
875  * the polyhash stage is skipped and ip_short is applied directly to the
876  * NH output.
877  */
878 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
879 {
880     UINT64 t;
881     UINT64 *nhp = (UINT64 *)nh_res;
882 
883     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
884     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
885 #if (UMAC_OUTPUT_LEN >= 8)
886     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
887     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
888 #endif
889 #if (UMAC_OUTPUT_LEN >= 12)
890     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
891     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
892 #endif
893 #if (UMAC_OUTPUT_LEN == 16)
894     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
895     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
896 #endif
897 }
898 
899 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
900  * the polyhash stage is not skipped and ip_long is applied to the
901  * polyhash output.
902  */
903 static void ip_long(uhash_ctx_t ahc, u_char *res)
904 {
905     int i;
906     UINT64 t;
907 
908     for (i = 0; i < STREAMS; i++) {
909         /* fix polyhash output not in Z_p64 */
910         if (ahc->poly_accum[i] >= p64)
911             ahc->poly_accum[i] -= p64;
912         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
913         STORE_UINT32_BIG((UINT32 *)res+i,
914                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
915     }
916 }
917 
918 
919 /* ---------------------------------------------------------------------- */
920 
921 /* ---------------------------------------------------------------------- */
922 
923 /* Reset uhash context for next hash session */
924 static int uhash_reset(uhash_ctx_t pc)
925 {
926     nh_reset(&pc->hash);
927     pc->msg_len = 0;
928     pc->poly_accum[0] = 1;
929 #if (UMAC_OUTPUT_LEN >= 8)
930     pc->poly_accum[1] = 1;
931 #endif
932 #if (UMAC_OUTPUT_LEN >= 12)
933     pc->poly_accum[2] = 1;
934 #endif
935 #if (UMAC_OUTPUT_LEN == 16)
936     pc->poly_accum[3] = 1;
937 #endif
938     return 1;
939 }
940 
941 /* ---------------------------------------------------------------------- */
942 
943 /* Given a pointer to the internal key needed by kdf() and a uhash context,
944  * initialize the NH context and generate keys needed for poly and inner-
945  * product hashing. All keys are endian adjusted in memory so that native
946  * loads cause correct keys to be in registers during calculation.
947  */
948 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
949 {
950     int i;
951     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
952 
953     /* Zero the entire uhash context */
954     memset(ahc, 0, sizeof(uhash_ctx));
955 
956     /* Initialize the L1 hash */
957     nh_init(&ahc->hash, prf_key);
958 
959     /* Setup L2 hash variables */
960     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
961     for (i = 0; i < STREAMS; i++) {
962         /* Fill keys from the buffer, skipping bytes in the buffer not
963          * used by this implementation. Endian reverse the keys if on a
964          * little-endian computer.
965          */
966         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
967         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
968         /* Mask the 64-bit keys to their special domain */
969         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
970         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
971     }
972 
973     /* Setup L3-1 hash variables */
974     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
975     for (i = 0; i < STREAMS; i++)
976           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
977                                                  4*sizeof(UINT64));
978     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
979                                                   sizeof(ahc->ip_keys));
980     for (i = 0; i < STREAMS*4; i++)
981         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
982 
983     /* Setup L3-2 hash variables    */
984     /* Fill buffer with index 4 key */
985     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
986     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
987                          STREAMS * sizeof(UINT32));
988 }
989 
990 /* ---------------------------------------------------------------------- */
991 
992 #if 0
993 static uhash_ctx_t uhash_alloc(u_char key[])
994 {
995 /* Allocate memory and force to a 16-byte boundary. */
996     uhash_ctx_t ctx;
997     u_char bytes_to_add;
998     aes_int_key prf_key;
999 
1000     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1001     if (ctx) {
1002         if (ALLOC_BOUNDARY) {
1003             bytes_to_add = ALLOC_BOUNDARY -
1004                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1005             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1006             *((u_char *)ctx - 1) = bytes_to_add;
1007         }
1008         aes_key_setup(key,prf_key);
1009         uhash_init(ctx, prf_key);
1010     }
1011     return (ctx);
1012 }
1013 #endif
1014 
1015 /* ---------------------------------------------------------------------- */
1016 
1017 #if 0
1018 static int uhash_free(uhash_ctx_t ctx)
1019 {
1020 /* Free memory allocated by uhash_alloc */
1021     u_char bytes_to_sub;
1022 
1023     if (ctx) {
1024         if (ALLOC_BOUNDARY) {
1025             bytes_to_sub = *((u_char *)ctx - 1);
1026             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1027         }
1028         free(ctx);
1029     }
1030     return (1);
1031 }
1032 #endif
1033 /* ---------------------------------------------------------------------- */
1034 
1035 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1036 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1037  * hash each one with NH, calling the polyhash on each NH output.
1038  */
1039 {
1040     UWORD bytes_hashed, bytes_remaining;
1041     UINT64 result_buf[STREAMS];
1042     UINT8 *nh_result = (UINT8 *)&result_buf;
1043 
1044     if (ctx->msg_len + len <= L1_KEY_LEN) {
1045         nh_update(&ctx->hash, (const UINT8 *)input, len);
1046         ctx->msg_len += len;
1047     } else {
1048 
1049          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1050          if (ctx->msg_len == L1_KEY_LEN)
1051              bytes_hashed = L1_KEY_LEN;
1052 
1053          if (bytes_hashed + len >= L1_KEY_LEN) {
1054 
1055              /* If some bytes have been passed to the hash function      */
1056              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1057              /* bytes to complete the current nh_block.                  */
1058              if (bytes_hashed) {
1059                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1060                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1061                  nh_final(&ctx->hash, nh_result);
1062                  ctx->msg_len += bytes_remaining;
1063                  poly_hash(ctx,(UINT32 *)nh_result);
1064                  len -= bytes_remaining;
1065                  input += bytes_remaining;
1066              }
1067 
1068              /* Hash directly from input stream if enough bytes */
1069              while (len >= L1_KEY_LEN) {
1070                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1071                                    L1_KEY_LEN, nh_result);
1072                  ctx->msg_len += L1_KEY_LEN;
1073                  len -= L1_KEY_LEN;
1074                  input += L1_KEY_LEN;
1075                  poly_hash(ctx,(UINT32 *)nh_result);
1076              }
1077          }
1078 
1079          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1080          if (len) {
1081              nh_update(&ctx->hash, (const UINT8 *)input, len);
1082              ctx->msg_len += len;
1083          }
1084      }
1085 
1086     return (1);
1087 }
1088 
1089 /* ---------------------------------------------------------------------- */
1090 
1091 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1092 /* Incorporate any pending data, pad, and generate tag */
1093 {
1094     UINT64 result_buf[STREAMS];
1095     UINT8 *nh_result = (UINT8 *)&result_buf;
1096 
1097     if (ctx->msg_len > L1_KEY_LEN) {
1098         if (ctx->msg_len % L1_KEY_LEN) {
1099             nh_final(&ctx->hash, nh_result);
1100             poly_hash(ctx,(UINT32 *)nh_result);
1101         }
1102         ip_long(ctx, res);
1103     } else {
1104         nh_final(&ctx->hash, nh_result);
1105         ip_short(ctx,nh_result, res);
1106     }
1107     uhash_reset(ctx);
1108     return (1);
1109 }
1110 
1111 /* ---------------------------------------------------------------------- */
1112 
1113 #if 0
1114 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1115 /* assumes that msg is in a writable buffer of length divisible by */
1116 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1117 {
1118     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1119     UINT32 nh_len;
1120     int extra_zeroes_needed;
1121 
1122     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1123      * the polyhash.
1124      */
1125     if (len <= L1_KEY_LEN) {
1126     	if (len == 0)                  /* If zero length messages will not */
1127     		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1128     	else
1129         	nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1130         extra_zeroes_needed = nh_len - len;
1131         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1132         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1133         ip_short(ahc,nh_result, res);
1134     } else {
1135         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1136          * output to poly_hash().
1137          */
1138         do {
1139             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1140             poly_hash(ahc,(UINT32 *)nh_result);
1141             len -= L1_KEY_LEN;
1142             msg += L1_KEY_LEN;
1143         } while (len >= L1_KEY_LEN);
1144         if (len) {
1145             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1146             extra_zeroes_needed = nh_len - len;
1147             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1148             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1149             poly_hash(ahc,(UINT32 *)nh_result);
1150         }
1151 
1152         ip_long(ahc, res);
1153     }
1154 
1155     uhash_reset(ahc);
1156     return 1;
1157 }
1158 #endif
1159 
1160 /* ---------------------------------------------------------------------- */
1161 /* ---------------------------------------------------------------------- */
1162 /* ----- Begin UMAC Section --------------------------------------------- */
1163 /* ---------------------------------------------------------------------- */
1164 /* ---------------------------------------------------------------------- */
1165 
1166 /* The UMAC interface has two interfaces, an all-at-once interface where
1167  * the entire message to be authenticated is passed to UMAC in one buffer,
1168  * and a sequential interface where the message is presented a little at a
1169  * time. The all-at-once is more optimaized than the sequential version and
1170  * should be preferred when the sequential interface is not required.
1171  */
1172 struct umac_ctx {
1173     uhash_ctx hash;          /* Hash function for message compression    */
1174     pdf_ctx pdf;             /* PDF for hashed output                    */
1175     void *free_ptr;          /* Address to free this struct via          */
1176 } umac_ctx;
1177 
1178 /* ---------------------------------------------------------------------- */
1179 
1180 #if 0
1181 int umac_reset(struct umac_ctx *ctx)
1182 /* Reset the hash function to begin a new authentication.        */
1183 {
1184     uhash_reset(&ctx->hash);
1185     return (1);
1186 }
1187 #endif
1188 
1189 /* ---------------------------------------------------------------------- */
1190 
1191 int umac_delete(struct umac_ctx *ctx)
1192 /* Deallocate the ctx structure */
1193 {
1194     if (ctx) {
1195         if (ALLOC_BOUNDARY)
1196             ctx = (struct umac_ctx *)ctx->free_ptr;
1197         free(ctx);
1198     }
1199     return (1);
1200 }
1201 
1202 /* ---------------------------------------------------------------------- */
1203 
1204 struct umac_ctx *umac_new(const u_char key[])
1205 /* Dynamically allocate a umac_ctx struct, initialize variables,
1206  * generate subkeys from key. Align to 16-byte boundary.
1207  */
1208 {
1209     struct umac_ctx *ctx, *octx;
1210     size_t bytes_to_add;
1211     aes_int_key prf_key;
1212 
1213     octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1214     if (ctx) {
1215         if (ALLOC_BOUNDARY) {
1216             bytes_to_add = ALLOC_BOUNDARY -
1217                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1218             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1219         }
1220         ctx->free_ptr = octx;
1221         aes_key_setup(key, prf_key);
1222         pdf_init(&ctx->pdf, prf_key);
1223         uhash_init(&ctx->hash, prf_key);
1224     }
1225 
1226     return (ctx);
1227 }
1228 
1229 /* ---------------------------------------------------------------------- */
1230 
1231 int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1232 /* Incorporate any pending data, pad, and generate tag */
1233 {
1234     uhash_final(&ctx->hash, (u_char *)tag);
1235     pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1236 
1237     return (1);
1238 }
1239 
1240 /* ---------------------------------------------------------------------- */
1241 
1242 int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1243 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1244 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1245 /* output buffer is full.                                                 */
1246 {
1247     uhash_update(&ctx->hash, input, len);
1248     return (1);
1249 }
1250 
1251 /* ---------------------------------------------------------------------- */
1252 
1253 #if 0
1254 int umac(struct umac_ctx *ctx, u_char *input,
1255          long len, u_char tag[],
1256          u_char nonce[8])
1257 /* All-in-one version simply calls umac_update() and umac_final().        */
1258 {
1259     uhash(&ctx->hash, input, len, (u_char *)tag);
1260     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1261 
1262     return (1);
1263 }
1264 #endif
1265 
1266 /* ---------------------------------------------------------------------- */
1267 /* ---------------------------------------------------------------------- */
1268 /* ----- End UMAC Section ----------------------------------------------- */
1269 /* ---------------------------------------------------------------------- */
1270 /* ---------------------------------------------------------------------- */
1271