xref: /freebsd/crypto/openssh/umac.c (revision cc16dea626cf2fc80cde667ac4798065108e596c)
1 /* $OpenBSD: umac.c,v 1.4 2011/10/19 10:39:48 djm 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 #ifndef UMAC_OUTPUT_LEN
56 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
57 #endif
58 
59 #if UMAC_OUTPUT_LEN != 4 && UMAC_OUTPUT_LEN != 8 && \
60     UMAC_OUTPUT_LEN != 12 && UMAC_OUTPUT_LEN != 16
61 # error UMAC_OUTPUT_LEN must be defined to 4, 8, 12 or 16
62 #endif
63 
64 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
65 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
66 /* #define SSE2                0  Is SSE2 is available?                   */
67 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
68 /* #define UMAC_AE_SUPPORT     0  Enable auhthenticated encrytion         */
69 
70 /* ---------------------------------------------------------------------- */
71 /* -- Global Includes --------------------------------------------------- */
72 /* ---------------------------------------------------------------------- */
73 
74 #include "includes.h"
75 #include <sys/types.h>
76 
77 #include "xmalloc.h"
78 #include "umac.h"
79 #include <string.h>
80 #include <stdlib.h>
81 #include <stddef.h>
82 
83 /* ---------------------------------------------------------------------- */
84 /* --- Primitive Data Types ---                                           */
85 /* ---------------------------------------------------------------------- */
86 
87 /* The following assumptions may need change on your system */
88 typedef u_int8_t	UINT8;  /* 1 byte   */
89 typedef u_int16_t	UINT16; /* 2 byte   */
90 typedef u_int32_t	UINT32; /* 4 byte   */
91 typedef u_int64_t	UINT64; /* 8 bytes  */
92 typedef unsigned int	UWORD;  /* Register */
93 
94 /* ---------------------------------------------------------------------- */
95 /* --- Constants -------------------------------------------------------- */
96 /* ---------------------------------------------------------------------- */
97 
98 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
99 
100 /* Message "words" are read from memory in an endian-specific manner.     */
101 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
102 /* be set true if the host computer is little-endian.                     */
103 
104 #if BYTE_ORDER == LITTLE_ENDIAN
105 #define __LITTLE_ENDIAN__ 1
106 #else
107 #define __LITTLE_ENDIAN__ 0
108 #endif
109 
110 /* ---------------------------------------------------------------------- */
111 /* ---------------------------------------------------------------------- */
112 /* ----- Architecture Specific ------------------------------------------ */
113 /* ---------------------------------------------------------------------- */
114 /* ---------------------------------------------------------------------- */
115 
116 
117 /* ---------------------------------------------------------------------- */
118 /* ---------------------------------------------------------------------- */
119 /* ----- Primitive Routines --------------------------------------------- */
120 /* ---------------------------------------------------------------------- */
121 /* ---------------------------------------------------------------------- */
122 
123 
124 /* ---------------------------------------------------------------------- */
125 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
126 /* ---------------------------------------------------------------------- */
127 
128 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
129 
130 /* ---------------------------------------------------------------------- */
131 /* --- Endian Conversion --- Forcing assembly on some platforms           */
132 /* ---------------------------------------------------------------------- */
133 
134 #if HAVE_SWAP32
135 #define LOAD_UINT32_REVERSED(p)		(swap32(*(UINT32 *)(p)))
136 #define STORE_UINT32_REVERSED(p,v) 	(*(UINT32 *)(p) = swap32(v))
137 #else /* HAVE_SWAP32 */
138 
139 static UINT32 LOAD_UINT32_REVERSED(void *ptr)
140 {
141     UINT32 temp = *(UINT32 *)ptr;
142     temp = (temp >> 24) | ((temp & 0x00FF0000) >> 8 )
143          | ((temp & 0x0000FF00) << 8 ) | (temp << 24);
144     return (UINT32)temp;
145 }
146 
147 # if (__LITTLE_ENDIAN__)
148 static void STORE_UINT32_REVERSED(void *ptr, UINT32 x)
149 {
150     UINT32 i = (UINT32)x;
151     *(UINT32 *)ptr = (i >> 24) | ((i & 0x00FF0000) >> 8 )
152                    | ((i & 0x0000FF00) << 8 ) | (i << 24);
153 }
154 # endif /* __LITTLE_ENDIAN */
155 #endif /* HAVE_SWAP32 */
156 
157 /* The following definitions use the above reversal-primitives to do the right
158  * thing on endian specific load and stores.
159  */
160 
161 #if (__LITTLE_ENDIAN__)
162 #define LOAD_UINT32_LITTLE(ptr)     (*(UINT32 *)(ptr))
163 #define STORE_UINT32_BIG(ptr,x)     STORE_UINT32_REVERSED(ptr,x)
164 #else
165 #define LOAD_UINT32_LITTLE(ptr)     LOAD_UINT32_REVERSED(ptr)
166 #define STORE_UINT32_BIG(ptr,x)     (*(UINT32 *)(ptr) = (UINT32)(x))
167 #endif
168 
169 /* ---------------------------------------------------------------------- */
170 /* ---------------------------------------------------------------------- */
171 /* ----- Begin KDF & PDF Section ---------------------------------------- */
172 /* ---------------------------------------------------------------------- */
173 /* ---------------------------------------------------------------------- */
174 
175 /* UMAC uses AES with 16 byte block and key lengths */
176 #define AES_BLOCK_LEN  16
177 
178 /* OpenSSL's AES */
179 #include "openbsd-compat/openssl-compat.h"
180 #ifndef USE_BUILTIN_RIJNDAEL
181 # include <openssl/aes.h>
182 #endif
183 typedef AES_KEY aes_int_key[1];
184 #define aes_encryption(in,out,int_key)                  \
185   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
186 #define aes_key_setup(key,int_key)                      \
187   AES_set_encrypt_key((u_char *)(key),UMAC_KEY_LEN*8,int_key)
188 
189 /* The user-supplied UMAC key is stretched using AES in a counter
190  * mode to supply all random bits needed by UMAC. The kdf function takes
191  * an AES internal key representation 'key' and writes a stream of
192  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
193  * 'ndx' causes a distinct byte stream.
194  */
195 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
196 {
197     UINT8 in_buf[AES_BLOCK_LEN] = {0};
198     UINT8 out_buf[AES_BLOCK_LEN];
199     UINT8 *dst_buf = (UINT8 *)bufp;
200     int i;
201 
202     /* Setup the initial value */
203     in_buf[AES_BLOCK_LEN-9] = ndx;
204     in_buf[AES_BLOCK_LEN-1] = i = 1;
205 
206     while (nbytes >= AES_BLOCK_LEN) {
207         aes_encryption(in_buf, out_buf, key);
208         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
209         in_buf[AES_BLOCK_LEN-1] = ++i;
210         nbytes -= AES_BLOCK_LEN;
211         dst_buf += AES_BLOCK_LEN;
212     }
213     if (nbytes) {
214         aes_encryption(in_buf, out_buf, key);
215         memcpy(dst_buf,out_buf,nbytes);
216     }
217 }
218 
219 /* The final UHASH result is XOR'd with the output of a pseudorandom
220  * function. Here, we use AES to generate random output and
221  * xor the appropriate bytes depending on the last bits of nonce.
222  * This scheme is optimized for sequential, increasing big-endian nonces.
223  */
224 
225 typedef struct {
226     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
227     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
228     aes_int_key prf_key;         /* Expanded AES key for PDF          */
229 } pdf_ctx;
230 
231 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
232 {
233     UINT8 buf[UMAC_KEY_LEN];
234 
235     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
236     aes_key_setup(buf, pc->prf_key);
237 
238     /* Initialize pdf and cache */
239     memset(pc->nonce, 0, sizeof(pc->nonce));
240     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
241 }
242 
243 static void pdf_gen_xor(pdf_ctx *pc, UINT8 nonce[8], UINT8 buf[8])
244 {
245     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
246      * of the AES output. If last time around we returned the ndx-1st
247      * element, then we may have the result in the cache already.
248      */
249 
250 #if (UMAC_OUTPUT_LEN == 4)
251 #define LOW_BIT_MASK 3
252 #elif (UMAC_OUTPUT_LEN == 8)
253 #define LOW_BIT_MASK 1
254 #elif (UMAC_OUTPUT_LEN > 8)
255 #define LOW_BIT_MASK 0
256 #endif
257 
258     UINT8 tmp_nonce_lo[4];
259 #if LOW_BIT_MASK != 0
260     int ndx = nonce[7] & LOW_BIT_MASK;
261 #endif
262     *(UINT32 *)tmp_nonce_lo = ((UINT32 *)nonce)[1];
263     tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
264 
265     if ( (((UINT32 *)tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
266          (((UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
267     {
268         ((UINT32 *)pc->nonce)[0] = ((UINT32 *)nonce)[0];
269         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)tmp_nonce_lo)[0];
270         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
271     }
272 
273 #if (UMAC_OUTPUT_LEN == 4)
274     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
275 #elif (UMAC_OUTPUT_LEN == 8)
276     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
277 #elif (UMAC_OUTPUT_LEN == 12)
278     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
279     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
280 #elif (UMAC_OUTPUT_LEN == 16)
281     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
282     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
283 #endif
284 }
285 
286 /* ---------------------------------------------------------------------- */
287 /* ---------------------------------------------------------------------- */
288 /* ----- Begin NH Hash Section ------------------------------------------ */
289 /* ---------------------------------------------------------------------- */
290 /* ---------------------------------------------------------------------- */
291 
292 /* The NH-based hash functions used in UMAC are described in the UMAC paper
293  * and specification, both of which can be found at the UMAC website.
294  * The interface to this implementation has two
295  * versions, one expects the entire message being hashed to be passed
296  * in a single buffer and returns the hash result immediately. The second
297  * allows the message to be passed in a sequence of buffers. In the
298  * muliple-buffer interface, the client calls the routine nh_update() as
299  * many times as necessary. When there is no more data to be fed to the
300  * hash, the client calls nh_final() which calculates the hash output.
301  * Before beginning another hash calculation the nh_reset() routine
302  * must be called. The single-buffer routine, nh(), is equivalent to
303  * the sequence of calls nh_update() and nh_final(); however it is
304  * optimized and should be prefered whenever the multiple-buffer interface
305  * is not necessary. When using either interface, it is the client's
306  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
307  *
308  * The routine nh_init() initializes the nh_ctx data structure and
309  * must be called once, before any other PDF routine.
310  */
311 
312  /* The "nh_aux" routines do the actual NH hashing work. They
313   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
314   * produce output for all STREAMS NH iterations in one call,
315   * allowing the parallel implementation of the streams.
316   */
317 
318 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
319 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
320 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
321 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
322 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
323 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
324 
325 typedef struct {
326     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
327     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
328     int next_data_empty;    /* Bookeeping variable for data buffer.       */
329     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
330     UINT64 state[STREAMS];               /* on-line state     */
331 } nh_ctx;
332 
333 
334 #if (UMAC_OUTPUT_LEN == 4)
335 
336 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
337 /* NH hashing primitive. Previous (partial) hash result is loaded and
338 * then stored via hp pointer. The length of the data pointed at by "dp",
339 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
340 * is expected to be endian compensated in memory at key setup.
341 */
342 {
343     UINT64 h;
344     UWORD c = dlen / 32;
345     UINT32 *k = (UINT32 *)kp;
346     UINT32 *d = (UINT32 *)dp;
347     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
348     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
349 
350     h = *((UINT64 *)hp);
351     do {
352         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
353         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
354         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
355         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
356         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
357         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
358         h += MUL64((k0 + d0), (k4 + d4));
359         h += MUL64((k1 + d1), (k5 + d5));
360         h += MUL64((k2 + d2), (k6 + d6));
361         h += MUL64((k3 + d3), (k7 + d7));
362 
363         d += 8;
364         k += 8;
365     } while (--c);
366   *((UINT64 *)hp) = h;
367 }
368 
369 #elif (UMAC_OUTPUT_LEN == 8)
370 
371 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
372 /* Same as previous nh_aux, but two streams are handled in one pass,
373  * reading and writing 16 bytes of hash-state per call.
374  */
375 {
376   UINT64 h1,h2;
377   UWORD c = dlen / 32;
378   UINT32 *k = (UINT32 *)kp;
379   UINT32 *d = (UINT32 *)dp;
380   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
381   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
382         k8,k9,k10,k11;
383 
384   h1 = *((UINT64 *)hp);
385   h2 = *((UINT64 *)hp + 1);
386   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
387   do {
388     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
389     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
390     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
391     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
392     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
393     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
394 
395     h1 += MUL64((k0 + d0), (k4 + d4));
396     h2 += MUL64((k4 + d0), (k8 + d4));
397 
398     h1 += MUL64((k1 + d1), (k5 + d5));
399     h2 += MUL64((k5 + d1), (k9 + d5));
400 
401     h1 += MUL64((k2 + d2), (k6 + d6));
402     h2 += MUL64((k6 + d2), (k10 + d6));
403 
404     h1 += MUL64((k3 + d3), (k7 + d7));
405     h2 += MUL64((k7 + d3), (k11 + d7));
406 
407     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
408 
409     d += 8;
410     k += 8;
411   } while (--c);
412   ((UINT64 *)hp)[0] = h1;
413   ((UINT64 *)hp)[1] = h2;
414 }
415 
416 #elif (UMAC_OUTPUT_LEN == 12)
417 
418 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
419 /* Same as previous nh_aux, but two streams are handled in one pass,
420  * reading and writing 24 bytes of hash-state per call.
421 */
422 {
423     UINT64 h1,h2,h3;
424     UWORD c = dlen / 32;
425     UINT32 *k = (UINT32 *)kp;
426     UINT32 *d = (UINT32 *)dp;
427     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
428     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
429         k8,k9,k10,k11,k12,k13,k14,k15;
430 
431     h1 = *((UINT64 *)hp);
432     h2 = *((UINT64 *)hp + 1);
433     h3 = *((UINT64 *)hp + 2);
434     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
435     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
436     do {
437         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
438         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
439         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
440         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
441         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
442         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
443 
444         h1 += MUL64((k0 + d0), (k4 + d4));
445         h2 += MUL64((k4 + d0), (k8 + d4));
446         h3 += MUL64((k8 + d0), (k12 + d4));
447 
448         h1 += MUL64((k1 + d1), (k5 + d5));
449         h2 += MUL64((k5 + d1), (k9 + d5));
450         h3 += MUL64((k9 + d1), (k13 + d5));
451 
452         h1 += MUL64((k2 + d2), (k6 + d6));
453         h2 += MUL64((k6 + d2), (k10 + d6));
454         h3 += MUL64((k10 + d2), (k14 + d6));
455 
456         h1 += MUL64((k3 + d3), (k7 + d7));
457         h2 += MUL64((k7 + d3), (k11 + d7));
458         h3 += MUL64((k11 + d3), (k15 + d7));
459 
460         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
461         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
462 
463         d += 8;
464         k += 8;
465     } while (--c);
466     ((UINT64 *)hp)[0] = h1;
467     ((UINT64 *)hp)[1] = h2;
468     ((UINT64 *)hp)[2] = h3;
469 }
470 
471 #elif (UMAC_OUTPUT_LEN == 16)
472 
473 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
474 /* Same as previous nh_aux, but two streams are handled in one pass,
475  * reading and writing 24 bytes of hash-state per call.
476 */
477 {
478     UINT64 h1,h2,h3,h4;
479     UWORD c = dlen / 32;
480     UINT32 *k = (UINT32 *)kp;
481     UINT32 *d = (UINT32 *)dp;
482     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
483     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
484         k8,k9,k10,k11,k12,k13,k14,k15,
485         k16,k17,k18,k19;
486 
487     h1 = *((UINT64 *)hp);
488     h2 = *((UINT64 *)hp + 1);
489     h3 = *((UINT64 *)hp + 2);
490     h4 = *((UINT64 *)hp + 3);
491     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
492     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
493     do {
494         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
495         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
496         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
497         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
498         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
499         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
500         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
501 
502         h1 += MUL64((k0 + d0), (k4 + d4));
503         h2 += MUL64((k4 + d0), (k8 + d4));
504         h3 += MUL64((k8 + d0), (k12 + d4));
505         h4 += MUL64((k12 + d0), (k16 + d4));
506 
507         h1 += MUL64((k1 + d1), (k5 + d5));
508         h2 += MUL64((k5 + d1), (k9 + d5));
509         h3 += MUL64((k9 + d1), (k13 + d5));
510         h4 += MUL64((k13 + d1), (k17 + d5));
511 
512         h1 += MUL64((k2 + d2), (k6 + d6));
513         h2 += MUL64((k6 + d2), (k10 + d6));
514         h3 += MUL64((k10 + d2), (k14 + d6));
515         h4 += MUL64((k14 + d2), (k18 + d6));
516 
517         h1 += MUL64((k3 + d3), (k7 + d7));
518         h2 += MUL64((k7 + d3), (k11 + d7));
519         h3 += MUL64((k11 + d3), (k15 + d7));
520         h4 += MUL64((k15 + d3), (k19 + d7));
521 
522         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
523         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
524         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
525 
526         d += 8;
527         k += 8;
528     } while (--c);
529     ((UINT64 *)hp)[0] = h1;
530     ((UINT64 *)hp)[1] = h2;
531     ((UINT64 *)hp)[2] = h3;
532     ((UINT64 *)hp)[3] = h4;
533 }
534 
535 /* ---------------------------------------------------------------------- */
536 #endif  /* UMAC_OUTPUT_LENGTH */
537 /* ---------------------------------------------------------------------- */
538 
539 
540 /* ---------------------------------------------------------------------- */
541 
542 static void nh_transform(nh_ctx *hc, UINT8 *buf, UINT32 nbytes)
543 /* This function is a wrapper for the primitive NH hash functions. It takes
544  * as argument "hc" the current hash context and a buffer which must be a
545  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
546  * appropriately according to how much message has been hashed already.
547  */
548 {
549     UINT8 *key;
550 
551     key = hc->nh_key + hc->bytes_hashed;
552     nh_aux(key, buf, hc->state, nbytes);
553 }
554 
555 /* ---------------------------------------------------------------------- */
556 
557 #if (__LITTLE_ENDIAN__)
558 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
559 /* We endian convert the keys on little-endian computers to               */
560 /* compensate for the lack of big-endian memory reads during hashing.     */
561 {
562     UWORD iters = num_bytes / bpw;
563     if (bpw == 4) {
564         UINT32 *p = (UINT32 *)buf;
565         do {
566             *p = LOAD_UINT32_REVERSED(p);
567             p++;
568         } while (--iters);
569     } else if (bpw == 8) {
570         UINT32 *p = (UINT32 *)buf;
571         UINT32 t;
572         do {
573             t = LOAD_UINT32_REVERSED(p+1);
574             p[1] = LOAD_UINT32_REVERSED(p);
575             p[0] = t;
576             p += 2;
577         } while (--iters);
578     }
579 }
580 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
581 #else
582 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
583 #endif
584 
585 /* ---------------------------------------------------------------------- */
586 
587 static void nh_reset(nh_ctx *hc)
588 /* Reset nh_ctx to ready for hashing of new data */
589 {
590     hc->bytes_hashed = 0;
591     hc->next_data_empty = 0;
592     hc->state[0] = 0;
593 #if (UMAC_OUTPUT_LEN >= 8)
594     hc->state[1] = 0;
595 #endif
596 #if (UMAC_OUTPUT_LEN >= 12)
597     hc->state[2] = 0;
598 #endif
599 #if (UMAC_OUTPUT_LEN == 16)
600     hc->state[3] = 0;
601 #endif
602 
603 }
604 
605 /* ---------------------------------------------------------------------- */
606 
607 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
608 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
609 {
610     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
611     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
612     nh_reset(hc);
613 }
614 
615 /* ---------------------------------------------------------------------- */
616 
617 static void nh_update(nh_ctx *hc, UINT8 *buf, UINT32 nbytes)
618 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
619 /* even multiple of HASH_BUF_BYTES.                                       */
620 {
621     UINT32 i,j;
622 
623     j = hc->next_data_empty;
624     if ((j + nbytes) >= HASH_BUF_BYTES) {
625         if (j) {
626             i = HASH_BUF_BYTES - j;
627             memcpy(hc->data+j, buf, i);
628             nh_transform(hc,hc->data,HASH_BUF_BYTES);
629             nbytes -= i;
630             buf += i;
631             hc->bytes_hashed += HASH_BUF_BYTES;
632         }
633         if (nbytes >= HASH_BUF_BYTES) {
634             i = nbytes & ~(HASH_BUF_BYTES - 1);
635             nh_transform(hc, buf, i);
636             nbytes -= i;
637             buf += i;
638             hc->bytes_hashed += i;
639         }
640         j = 0;
641     }
642     memcpy(hc->data + j, buf, nbytes);
643     hc->next_data_empty = j + nbytes;
644 }
645 
646 /* ---------------------------------------------------------------------- */
647 
648 static void zero_pad(UINT8 *p, int nbytes)
649 {
650 /* Write "nbytes" of zeroes, beginning at "p" */
651     if (nbytes >= (int)sizeof(UWORD)) {
652         while ((ptrdiff_t)p % sizeof(UWORD)) {
653             *p = 0;
654             nbytes--;
655             p++;
656         }
657         while (nbytes >= (int)sizeof(UWORD)) {
658             *(UWORD *)p = 0;
659             nbytes -= sizeof(UWORD);
660             p += sizeof(UWORD);
661         }
662     }
663     while (nbytes) {
664         *p = 0;
665         nbytes--;
666         p++;
667     }
668 }
669 
670 /* ---------------------------------------------------------------------- */
671 
672 static void nh_final(nh_ctx *hc, UINT8 *result)
673 /* After passing some number of data buffers to nh_update() for integration
674  * into an NH context, nh_final is called to produce a hash result. If any
675  * bytes are in the buffer hc->data, incorporate them into the
676  * NH context. Finally, add into the NH accumulation "state" the total number
677  * of bits hashed. The resulting numbers are written to the buffer "result".
678  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
679  */
680 {
681     int nh_len, nbits;
682 
683     if (hc->next_data_empty != 0) {
684         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
685                                                 ~(L1_PAD_BOUNDARY - 1));
686         zero_pad(hc->data + hc->next_data_empty,
687                                           nh_len - hc->next_data_empty);
688         nh_transform(hc, hc->data, nh_len);
689         hc->bytes_hashed += hc->next_data_empty;
690     } else if (hc->bytes_hashed == 0) {
691     	nh_len = L1_PAD_BOUNDARY;
692         zero_pad(hc->data, L1_PAD_BOUNDARY);
693         nh_transform(hc, hc->data, nh_len);
694     }
695 
696     nbits = (hc->bytes_hashed << 3);
697     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
698 #if (UMAC_OUTPUT_LEN >= 8)
699     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
700 #endif
701 #if (UMAC_OUTPUT_LEN >= 12)
702     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
703 #endif
704 #if (UMAC_OUTPUT_LEN == 16)
705     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
706 #endif
707     nh_reset(hc);
708 }
709 
710 /* ---------------------------------------------------------------------- */
711 
712 static void nh(nh_ctx *hc, UINT8 *buf, UINT32 padded_len,
713                UINT32 unpadded_len, UINT8 *result)
714 /* All-in-one nh_update() and nh_final() equivalent.
715  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
716  * well aligned
717  */
718 {
719     UINT32 nbits;
720 
721     /* Initialize the hash state */
722     nbits = (unpadded_len << 3);
723 
724     ((UINT64 *)result)[0] = nbits;
725 #if (UMAC_OUTPUT_LEN >= 8)
726     ((UINT64 *)result)[1] = nbits;
727 #endif
728 #if (UMAC_OUTPUT_LEN >= 12)
729     ((UINT64 *)result)[2] = nbits;
730 #endif
731 #if (UMAC_OUTPUT_LEN == 16)
732     ((UINT64 *)result)[3] = nbits;
733 #endif
734 
735     nh_aux(hc->nh_key, buf, result, padded_len);
736 }
737 
738 /* ---------------------------------------------------------------------- */
739 /* ---------------------------------------------------------------------- */
740 /* ----- Begin UHASH Section -------------------------------------------- */
741 /* ---------------------------------------------------------------------- */
742 /* ---------------------------------------------------------------------- */
743 
744 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
745  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
746  * unless the initial data to be hashed is short. After the polynomial-
747  * layer, an inner-product hash is used to produce the final UHASH output.
748  *
749  * UHASH provides two interfaces, one all-at-once and another where data
750  * buffers are presented sequentially. In the sequential interface, the
751  * UHASH client calls the routine uhash_update() as many times as necessary.
752  * When there is no more data to be fed to UHASH, the client calls
753  * uhash_final() which
754  * calculates the UHASH output. Before beginning another UHASH calculation
755  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
756  * uhash(), is equivalent to the sequence of calls uhash_update() and
757  * uhash_final(); however it is optimized and should be
758  * used whenever the sequential interface is not necessary.
759  *
760  * The routine uhash_init() initializes the uhash_ctx data structure and
761  * must be called once, before any other UHASH routine.
762  */
763 
764 /* ---------------------------------------------------------------------- */
765 /* ----- Constants and uhash_ctx ---------------------------------------- */
766 /* ---------------------------------------------------------------------- */
767 
768 /* ---------------------------------------------------------------------- */
769 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
770 /* ---------------------------------------------------------------------- */
771 
772 /* Primes and masks */
773 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
774 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
775 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
776 
777 
778 /* ---------------------------------------------------------------------- */
779 
780 typedef struct uhash_ctx {
781     nh_ctx hash;                          /* Hash context for L1 NH hash  */
782     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
783     UINT64 poly_accum[STREAMS];           /* poly hash result             */
784     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
785     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
786     UINT32 msg_len;                       /* Total length of data passed  */
787                                           /* to uhash */
788 } uhash_ctx;
789 typedef struct uhash_ctx *uhash_ctx_t;
790 
791 /* ---------------------------------------------------------------------- */
792 
793 
794 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
795  * word at a time. As described in the specification, poly32 and poly64
796  * require keys from special domains. The following implementations exploit
797  * the special domains to avoid overflow. The results are not guaranteed to
798  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
799  * patches any errant values.
800  */
801 
802 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
803 {
804     UINT32 key_hi = (UINT32)(key >> 32),
805            key_lo = (UINT32)key,
806            cur_hi = (UINT32)(cur >> 32),
807            cur_lo = (UINT32)cur,
808            x_lo,
809            x_hi;
810     UINT64 X,T,res;
811 
812     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
813     x_lo = (UINT32)X;
814     x_hi = (UINT32)(X >> 32);
815 
816     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
817 
818     T = ((UINT64)x_lo << 32);
819     res += T;
820     if (res < T)
821         res += 59;
822 
823     res += data;
824     if (res < data)
825         res += 59;
826 
827     return res;
828 }
829 
830 
831 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
832  * implementation does not handle all ramp levels. Because we don't handle
833  * the ramp up to p128 modulus in this implementation, we are limited to
834  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
835  * bytes input to UMAC per tag, ie. 16MB).
836  */
837 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
838 {
839     int i;
840     UINT64 *data=(UINT64*)data_in;
841 
842     for (i = 0; i < STREAMS; i++) {
843         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
844             hc->poly_accum[i] = poly64(hc->poly_accum[i],
845                                        hc->poly_key_8[i], p64 - 1);
846             hc->poly_accum[i] = poly64(hc->poly_accum[i],
847                                        hc->poly_key_8[i], (data[i] - 59));
848         } else {
849             hc->poly_accum[i] = poly64(hc->poly_accum[i],
850                                        hc->poly_key_8[i], data[i]);
851         }
852     }
853 }
854 
855 
856 /* ---------------------------------------------------------------------- */
857 
858 
859 /* The final step in UHASH is an inner-product hash. The poly hash
860  * produces a result not neccesarily WORD_LEN bytes long. The inner-
861  * product hash breaks the polyhash output into 16-bit chunks and
862  * multiplies each with a 36 bit key.
863  */
864 
865 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
866 {
867     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
868     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
869     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
870     t = t + ipkp[3] * (UINT64)(UINT16)(data);
871 
872     return t;
873 }
874 
875 static UINT32 ip_reduce_p36(UINT64 t)
876 {
877 /* Divisionless modular reduction */
878     UINT64 ret;
879 
880     ret = (t & m36) + 5 * (t >> 36);
881     if (ret >= p36)
882         ret -= p36;
883 
884     /* return least significant 32 bits */
885     return (UINT32)(ret);
886 }
887 
888 
889 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
890  * the polyhash stage is skipped and ip_short is applied directly to the
891  * NH output.
892  */
893 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
894 {
895     UINT64 t;
896     UINT64 *nhp = (UINT64 *)nh_res;
897 
898     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
899     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
900 #if (UMAC_OUTPUT_LEN >= 8)
901     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
902     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
903 #endif
904 #if (UMAC_OUTPUT_LEN >= 12)
905     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
906     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
907 #endif
908 #if (UMAC_OUTPUT_LEN == 16)
909     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
910     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
911 #endif
912 }
913 
914 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
915  * the polyhash stage is not skipped and ip_long is applied to the
916  * polyhash output.
917  */
918 static void ip_long(uhash_ctx_t ahc, u_char *res)
919 {
920     int i;
921     UINT64 t;
922 
923     for (i = 0; i < STREAMS; i++) {
924         /* fix polyhash output not in Z_p64 */
925         if (ahc->poly_accum[i] >= p64)
926             ahc->poly_accum[i] -= p64;
927         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
928         STORE_UINT32_BIG((UINT32 *)res+i,
929                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
930     }
931 }
932 
933 
934 /* ---------------------------------------------------------------------- */
935 
936 /* ---------------------------------------------------------------------- */
937 
938 /* Reset uhash context for next hash session */
939 static int uhash_reset(uhash_ctx_t pc)
940 {
941     nh_reset(&pc->hash);
942     pc->msg_len = 0;
943     pc->poly_accum[0] = 1;
944 #if (UMAC_OUTPUT_LEN >= 8)
945     pc->poly_accum[1] = 1;
946 #endif
947 #if (UMAC_OUTPUT_LEN >= 12)
948     pc->poly_accum[2] = 1;
949 #endif
950 #if (UMAC_OUTPUT_LEN == 16)
951     pc->poly_accum[3] = 1;
952 #endif
953     return 1;
954 }
955 
956 /* ---------------------------------------------------------------------- */
957 
958 /* Given a pointer to the internal key needed by kdf() and a uhash context,
959  * initialize the NH context and generate keys needed for poly and inner-
960  * product hashing. All keys are endian adjusted in memory so that native
961  * loads cause correct keys to be in registers during calculation.
962  */
963 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
964 {
965     int i;
966     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
967 
968     /* Zero the entire uhash context */
969     memset(ahc, 0, sizeof(uhash_ctx));
970 
971     /* Initialize the L1 hash */
972     nh_init(&ahc->hash, prf_key);
973 
974     /* Setup L2 hash variables */
975     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
976     for (i = 0; i < STREAMS; i++) {
977         /* Fill keys from the buffer, skipping bytes in the buffer not
978          * used by this implementation. Endian reverse the keys if on a
979          * little-endian computer.
980          */
981         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
982         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
983         /* Mask the 64-bit keys to their special domain */
984         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
985         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
986     }
987 
988     /* Setup L3-1 hash variables */
989     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
990     for (i = 0; i < STREAMS; i++)
991           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
992                                                  4*sizeof(UINT64));
993     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
994                                                   sizeof(ahc->ip_keys));
995     for (i = 0; i < STREAMS*4; i++)
996         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
997 
998     /* Setup L3-2 hash variables    */
999     /* Fill buffer with index 4 key */
1000     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
1001     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
1002                          STREAMS * sizeof(UINT32));
1003 }
1004 
1005 /* ---------------------------------------------------------------------- */
1006 
1007 #if 0
1008 static uhash_ctx_t uhash_alloc(u_char key[])
1009 {
1010 /* Allocate memory and force to a 16-byte boundary. */
1011     uhash_ctx_t ctx;
1012     u_char bytes_to_add;
1013     aes_int_key prf_key;
1014 
1015     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1016     if (ctx) {
1017         if (ALLOC_BOUNDARY) {
1018             bytes_to_add = ALLOC_BOUNDARY -
1019                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1020             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1021             *((u_char *)ctx - 1) = bytes_to_add;
1022         }
1023         aes_key_setup(key,prf_key);
1024         uhash_init(ctx, prf_key);
1025     }
1026     return (ctx);
1027 }
1028 #endif
1029 
1030 /* ---------------------------------------------------------------------- */
1031 
1032 #if 0
1033 static int uhash_free(uhash_ctx_t ctx)
1034 {
1035 /* Free memory allocated by uhash_alloc */
1036     u_char bytes_to_sub;
1037 
1038     if (ctx) {
1039         if (ALLOC_BOUNDARY) {
1040             bytes_to_sub = *((u_char *)ctx - 1);
1041             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1042         }
1043         free(ctx);
1044     }
1045     return (1);
1046 }
1047 #endif
1048 /* ---------------------------------------------------------------------- */
1049 
1050 static int uhash_update(uhash_ctx_t ctx, u_char *input, long len)
1051 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1052  * hash each one with NH, calling the polyhash on each NH output.
1053  */
1054 {
1055     UWORD bytes_hashed, bytes_remaining;
1056     UINT64 result_buf[STREAMS];
1057     UINT8 *nh_result = (UINT8 *)&result_buf;
1058 
1059     if (ctx->msg_len + len <= L1_KEY_LEN) {
1060         nh_update(&ctx->hash, (UINT8 *)input, len);
1061         ctx->msg_len += len;
1062     } else {
1063 
1064          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1065          if (ctx->msg_len == L1_KEY_LEN)
1066              bytes_hashed = L1_KEY_LEN;
1067 
1068          if (bytes_hashed + len >= L1_KEY_LEN) {
1069 
1070              /* If some bytes have been passed to the hash function      */
1071              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1072              /* bytes to complete the current nh_block.                  */
1073              if (bytes_hashed) {
1074                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1075                  nh_update(&ctx->hash, (UINT8 *)input, bytes_remaining);
1076                  nh_final(&ctx->hash, nh_result);
1077                  ctx->msg_len += bytes_remaining;
1078                  poly_hash(ctx,(UINT32 *)nh_result);
1079                  len -= bytes_remaining;
1080                  input += bytes_remaining;
1081              }
1082 
1083              /* Hash directly from input stream if enough bytes */
1084              while (len >= L1_KEY_LEN) {
1085                  nh(&ctx->hash, (UINT8 *)input, L1_KEY_LEN,
1086                                    L1_KEY_LEN, nh_result);
1087                  ctx->msg_len += L1_KEY_LEN;
1088                  len -= L1_KEY_LEN;
1089                  input += L1_KEY_LEN;
1090                  poly_hash(ctx,(UINT32 *)nh_result);
1091              }
1092          }
1093 
1094          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1095          if (len) {
1096              nh_update(&ctx->hash, (UINT8 *)input, len);
1097              ctx->msg_len += len;
1098          }
1099      }
1100 
1101     return (1);
1102 }
1103 
1104 /* ---------------------------------------------------------------------- */
1105 
1106 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1107 /* Incorporate any pending data, pad, and generate tag */
1108 {
1109     UINT64 result_buf[STREAMS];
1110     UINT8 *nh_result = (UINT8 *)&result_buf;
1111 
1112     if (ctx->msg_len > L1_KEY_LEN) {
1113         if (ctx->msg_len % L1_KEY_LEN) {
1114             nh_final(&ctx->hash, nh_result);
1115             poly_hash(ctx,(UINT32 *)nh_result);
1116         }
1117         ip_long(ctx, res);
1118     } else {
1119         nh_final(&ctx->hash, nh_result);
1120         ip_short(ctx,nh_result, res);
1121     }
1122     uhash_reset(ctx);
1123     return (1);
1124 }
1125 
1126 /* ---------------------------------------------------------------------- */
1127 
1128 #if 0
1129 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1130 /* assumes that msg is in a writable buffer of length divisible by */
1131 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1132 {
1133     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1134     UINT32 nh_len;
1135     int extra_zeroes_needed;
1136 
1137     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1138      * the polyhash.
1139      */
1140     if (len <= L1_KEY_LEN) {
1141     	if (len == 0)                  /* If zero length messages will not */
1142     		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1143     	else
1144         	nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1145         extra_zeroes_needed = nh_len - len;
1146         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1147         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1148         ip_short(ahc,nh_result, res);
1149     } else {
1150         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1151          * output to poly_hash().
1152          */
1153         do {
1154             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1155             poly_hash(ahc,(UINT32 *)nh_result);
1156             len -= L1_KEY_LEN;
1157             msg += L1_KEY_LEN;
1158         } while (len >= L1_KEY_LEN);
1159         if (len) {
1160             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1161             extra_zeroes_needed = nh_len - len;
1162             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1163             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1164             poly_hash(ahc,(UINT32 *)nh_result);
1165         }
1166 
1167         ip_long(ahc, res);
1168     }
1169 
1170     uhash_reset(ahc);
1171     return 1;
1172 }
1173 #endif
1174 
1175 /* ---------------------------------------------------------------------- */
1176 /* ---------------------------------------------------------------------- */
1177 /* ----- Begin UMAC Section --------------------------------------------- */
1178 /* ---------------------------------------------------------------------- */
1179 /* ---------------------------------------------------------------------- */
1180 
1181 /* The UMAC interface has two interfaces, an all-at-once interface where
1182  * the entire message to be authenticated is passed to UMAC in one buffer,
1183  * and a sequential interface where the message is presented a little at a
1184  * time. The all-at-once is more optimaized than the sequential version and
1185  * should be preferred when the sequential interface is not required.
1186  */
1187 struct umac_ctx {
1188     uhash_ctx hash;          /* Hash function for message compression    */
1189     pdf_ctx pdf;             /* PDF for hashed output                    */
1190     void *free_ptr;          /* Address to free this struct via          */
1191 } umac_ctx;
1192 
1193 /* ---------------------------------------------------------------------- */
1194 
1195 #if 0
1196 int umac_reset(struct umac_ctx *ctx)
1197 /* Reset the hash function to begin a new authentication.        */
1198 {
1199     uhash_reset(&ctx->hash);
1200     return (1);
1201 }
1202 #endif
1203 
1204 /* ---------------------------------------------------------------------- */
1205 
1206 int umac_delete(struct umac_ctx *ctx)
1207 /* Deallocate the ctx structure */
1208 {
1209     if (ctx) {
1210         if (ALLOC_BOUNDARY)
1211             ctx = (struct umac_ctx *)ctx->free_ptr;
1212         xfree(ctx);
1213     }
1214     return (1);
1215 }
1216 
1217 /* ---------------------------------------------------------------------- */
1218 
1219 struct umac_ctx *umac_new(u_char key[])
1220 /* Dynamically allocate a umac_ctx struct, initialize variables,
1221  * generate subkeys from key. Align to 16-byte boundary.
1222  */
1223 {
1224     struct umac_ctx *ctx, *octx;
1225     size_t bytes_to_add;
1226     aes_int_key prf_key;
1227 
1228     octx = ctx = xmalloc(sizeof(*ctx) + ALLOC_BOUNDARY);
1229     if (ctx) {
1230         if (ALLOC_BOUNDARY) {
1231             bytes_to_add = ALLOC_BOUNDARY -
1232                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1233             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1234         }
1235         ctx->free_ptr = octx;
1236         aes_key_setup(key,prf_key);
1237         pdf_init(&ctx->pdf, prf_key);
1238         uhash_init(&ctx->hash, prf_key);
1239     }
1240 
1241     return (ctx);
1242 }
1243 
1244 /* ---------------------------------------------------------------------- */
1245 
1246 int umac_final(struct umac_ctx *ctx, u_char tag[], u_char nonce[8])
1247 /* Incorporate any pending data, pad, and generate tag */
1248 {
1249     uhash_final(&ctx->hash, (u_char *)tag);
1250     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1251 
1252     return (1);
1253 }
1254 
1255 /* ---------------------------------------------------------------------- */
1256 
1257 int umac_update(struct umac_ctx *ctx, u_char *input, long len)
1258 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1259 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1260 /* output buffer is full.                                                 */
1261 {
1262     uhash_update(&ctx->hash, input, len);
1263     return (1);
1264 }
1265 
1266 /* ---------------------------------------------------------------------- */
1267 
1268 #if 0
1269 int umac(struct umac_ctx *ctx, u_char *input,
1270          long len, u_char tag[],
1271          u_char nonce[8])
1272 /* All-in-one version simply calls umac_update() and umac_final().        */
1273 {
1274     uhash(&ctx->hash, input, len, (u_char *)tag);
1275     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1276 
1277     return (1);
1278 }
1279 #endif
1280 
1281 /* ---------------------------------------------------------------------- */
1282 /* ---------------------------------------------------------------------- */
1283 /* ----- End UMAC Section ----------------------------------------------- */
1284 /* ---------------------------------------------------------------------- */
1285 /* ---------------------------------------------------------------------- */
1286