xref: /openbsd/usr.bin/ssh/umac.c (revision 6f40fd34)
1 /* $OpenBSD: umac.c,v 1.12 2017/05/31 08:09:45 markus 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     explicit_bzero(in_buf, sizeof(in_buf));
201     explicit_bzero(out_buf, sizeof(out_buf));
202 }
203 
204 /* The final UHASH result is XOR'd with the output of a pseudorandom
205  * function. Here, we use AES to generate random output and
206  * xor the appropriate bytes depending on the last bits of nonce.
207  * This scheme is optimized for sequential, increasing big-endian nonces.
208  */
209 
210 typedef struct {
211     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
212     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
213     aes_int_key prf_key;         /* Expanded AES key for PDF          */
214 } pdf_ctx;
215 
216 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
217 {
218     UINT8 buf[UMAC_KEY_LEN];
219 
220     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
221     aes_key_setup(buf, pc->prf_key);
222 
223     /* Initialize pdf and cache */
224     memset(pc->nonce, 0, sizeof(pc->nonce));
225     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
226     explicit_bzero(buf, sizeof(buf));
227 }
228 
229 static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8])
230 {
231     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
232      * of the AES output. If last time around we returned the ndx-1st
233      * element, then we may have the result in the cache already.
234      */
235 
236 #if (UMAC_OUTPUT_LEN == 4)
237 #define LOW_BIT_MASK 3
238 #elif (UMAC_OUTPUT_LEN == 8)
239 #define LOW_BIT_MASK 1
240 #elif (UMAC_OUTPUT_LEN > 8)
241 #define LOW_BIT_MASK 0
242 #endif
243     union {
244         UINT8 tmp_nonce_lo[4];
245         UINT32 align;
246     } t;
247 #if LOW_BIT_MASK != 0
248     int ndx = nonce[7] & LOW_BIT_MASK;
249 #endif
250     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
251     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
252 
253     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
254          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
255     {
256         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
257         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
258         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
259     }
260 
261 #if (UMAC_OUTPUT_LEN == 4)
262     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
263 #elif (UMAC_OUTPUT_LEN == 8)
264     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
265 #elif (UMAC_OUTPUT_LEN == 12)
266     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
267     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
268 #elif (UMAC_OUTPUT_LEN == 16)
269     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
270     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
271 #endif
272 }
273 
274 /* ---------------------------------------------------------------------- */
275 /* ---------------------------------------------------------------------- */
276 /* ----- Begin NH Hash Section ------------------------------------------ */
277 /* ---------------------------------------------------------------------- */
278 /* ---------------------------------------------------------------------- */
279 
280 /* The NH-based hash functions used in UMAC are described in the UMAC paper
281  * and specification, both of which can be found at the UMAC website.
282  * The interface to this implementation has two
283  * versions, one expects the entire message being hashed to be passed
284  * in a single buffer and returns the hash result immediately. The second
285  * allows the message to be passed in a sequence of buffers. In the
286  * muliple-buffer interface, the client calls the routine nh_update() as
287  * many times as necessary. When there is no more data to be fed to the
288  * hash, the client calls nh_final() which calculates the hash output.
289  * Before beginning another hash calculation the nh_reset() routine
290  * must be called. The single-buffer routine, nh(), is equivalent to
291  * the sequence of calls nh_update() and nh_final(); however it is
292  * optimized and should be prefered whenever the multiple-buffer interface
293  * is not necessary. When using either interface, it is the client's
294  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
295  *
296  * The routine nh_init() initializes the nh_ctx data structure and
297  * must be called once, before any other PDF routine.
298  */
299 
300  /* The "nh_aux" routines do the actual NH hashing work. They
301   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
302   * produce output for all STREAMS NH iterations in one call,
303   * allowing the parallel implementation of the streams.
304   */
305 
306 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
307 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
308 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
309 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
310 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
311 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
312 
313 typedef struct {
314     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
315     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
316     int next_data_empty;    /* Bookeeping variable for data buffer.       */
317     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
318     UINT64 state[STREAMS];               /* on-line state     */
319 } nh_ctx;
320 
321 
322 #if (UMAC_OUTPUT_LEN == 4)
323 
324 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
325 /* NH hashing primitive. Previous (partial) hash result is loaded and
326 * then stored via hp pointer. The length of the data pointed at by "dp",
327 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
328 * is expected to be endian compensated in memory at key setup.
329 */
330 {
331     UINT64 h;
332     UWORD c = dlen / 32;
333     UINT32 *k = (UINT32 *)kp;
334     const UINT32 *d = (const UINT32 *)dp;
335     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
336     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
337 
338     h = *((UINT64 *)hp);
339     do {
340         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
341         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
342         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
343         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
344         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
345         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
346         h += MUL64((k0 + d0), (k4 + d4));
347         h += MUL64((k1 + d1), (k5 + d5));
348         h += MUL64((k2 + d2), (k6 + d6));
349         h += MUL64((k3 + d3), (k7 + d7));
350 
351         d += 8;
352         k += 8;
353     } while (--c);
354   *((UINT64 *)hp) = h;
355 }
356 
357 #elif (UMAC_OUTPUT_LEN == 8)
358 
359 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
360 /* Same as previous nh_aux, but two streams are handled in one pass,
361  * reading and writing 16 bytes of hash-state per call.
362  */
363 {
364   UINT64 h1,h2;
365   UWORD c = dlen / 32;
366   UINT32 *k = (UINT32 *)kp;
367   const UINT32 *d = (const UINT32 *)dp;
368   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
369   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
370         k8,k9,k10,k11;
371 
372   h1 = *((UINT64 *)hp);
373   h2 = *((UINT64 *)hp + 1);
374   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
375   do {
376     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
377     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
378     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
379     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
380     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
381     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
382 
383     h1 += MUL64((k0 + d0), (k4 + d4));
384     h2 += MUL64((k4 + d0), (k8 + d4));
385 
386     h1 += MUL64((k1 + d1), (k5 + d5));
387     h2 += MUL64((k5 + d1), (k9 + d5));
388 
389     h1 += MUL64((k2 + d2), (k6 + d6));
390     h2 += MUL64((k6 + d2), (k10 + d6));
391 
392     h1 += MUL64((k3 + d3), (k7 + d7));
393     h2 += MUL64((k7 + d3), (k11 + d7));
394 
395     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
396 
397     d += 8;
398     k += 8;
399   } while (--c);
400   ((UINT64 *)hp)[0] = h1;
401   ((UINT64 *)hp)[1] = h2;
402 }
403 
404 #elif (UMAC_OUTPUT_LEN == 12)
405 
406 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
407 /* Same as previous nh_aux, but two streams are handled in one pass,
408  * reading and writing 24 bytes of hash-state per call.
409 */
410 {
411     UINT64 h1,h2,h3;
412     UWORD c = dlen / 32;
413     UINT32 *k = (UINT32 *)kp;
414     const UINT32 *d = (const UINT32 *)dp;
415     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
416     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
417         k8,k9,k10,k11,k12,k13,k14,k15;
418 
419     h1 = *((UINT64 *)hp);
420     h2 = *((UINT64 *)hp + 1);
421     h3 = *((UINT64 *)hp + 2);
422     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
423     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
424     do {
425         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
426         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
427         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
428         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
429         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
430         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
431 
432         h1 += MUL64((k0 + d0), (k4 + d4));
433         h2 += MUL64((k4 + d0), (k8 + d4));
434         h3 += MUL64((k8 + d0), (k12 + d4));
435 
436         h1 += MUL64((k1 + d1), (k5 + d5));
437         h2 += MUL64((k5 + d1), (k9 + d5));
438         h3 += MUL64((k9 + d1), (k13 + d5));
439 
440         h1 += MUL64((k2 + d2), (k6 + d6));
441         h2 += MUL64((k6 + d2), (k10 + d6));
442         h3 += MUL64((k10 + d2), (k14 + d6));
443 
444         h1 += MUL64((k3 + d3), (k7 + d7));
445         h2 += MUL64((k7 + d3), (k11 + d7));
446         h3 += MUL64((k11 + d3), (k15 + d7));
447 
448         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
449         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
450 
451         d += 8;
452         k += 8;
453     } while (--c);
454     ((UINT64 *)hp)[0] = h1;
455     ((UINT64 *)hp)[1] = h2;
456     ((UINT64 *)hp)[2] = h3;
457 }
458 
459 #elif (UMAC_OUTPUT_LEN == 16)
460 
461 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
462 /* Same as previous nh_aux, but two streams are handled in one pass,
463  * reading and writing 24 bytes of hash-state per call.
464 */
465 {
466     UINT64 h1,h2,h3,h4;
467     UWORD c = dlen / 32;
468     UINT32 *k = (UINT32 *)kp;
469     const UINT32 *d = (const UINT32 *)dp;
470     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
471     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
472         k8,k9,k10,k11,k12,k13,k14,k15,
473         k16,k17,k18,k19;
474 
475     h1 = *((UINT64 *)hp);
476     h2 = *((UINT64 *)hp + 1);
477     h3 = *((UINT64 *)hp + 2);
478     h4 = *((UINT64 *)hp + 3);
479     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
480     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
481     do {
482         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
483         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
484         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
485         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
486         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
487         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
488         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
489 
490         h1 += MUL64((k0 + d0), (k4 + d4));
491         h2 += MUL64((k4 + d0), (k8 + d4));
492         h3 += MUL64((k8 + d0), (k12 + d4));
493         h4 += MUL64((k12 + d0), (k16 + d4));
494 
495         h1 += MUL64((k1 + d1), (k5 + d5));
496         h2 += MUL64((k5 + d1), (k9 + d5));
497         h3 += MUL64((k9 + d1), (k13 + d5));
498         h4 += MUL64((k13 + d1), (k17 + d5));
499 
500         h1 += MUL64((k2 + d2), (k6 + d6));
501         h2 += MUL64((k6 + d2), (k10 + d6));
502         h3 += MUL64((k10 + d2), (k14 + d6));
503         h4 += MUL64((k14 + d2), (k18 + d6));
504 
505         h1 += MUL64((k3 + d3), (k7 + d7));
506         h2 += MUL64((k7 + d3), (k11 + d7));
507         h3 += MUL64((k11 + d3), (k15 + d7));
508         h4 += MUL64((k15 + d3), (k19 + d7));
509 
510         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
511         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
512         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
513 
514         d += 8;
515         k += 8;
516     } while (--c);
517     ((UINT64 *)hp)[0] = h1;
518     ((UINT64 *)hp)[1] = h2;
519     ((UINT64 *)hp)[2] = h3;
520     ((UINT64 *)hp)[3] = h4;
521 }
522 
523 /* ---------------------------------------------------------------------- */
524 #endif  /* UMAC_OUTPUT_LENGTH */
525 /* ---------------------------------------------------------------------- */
526 
527 
528 /* ---------------------------------------------------------------------- */
529 
530 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
531 /* This function is a wrapper for the primitive NH hash functions. It takes
532  * as argument "hc" the current hash context and a buffer which must be a
533  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
534  * appropriately according to how much message has been hashed already.
535  */
536 {
537     UINT8 *key;
538 
539     key = hc->nh_key + hc->bytes_hashed;
540     nh_aux(key, buf, hc->state, nbytes);
541 }
542 
543 /* ---------------------------------------------------------------------- */
544 
545 #if (__LITTLE_ENDIAN__)
546 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
547 /* We endian convert the keys on little-endian computers to               */
548 /* compensate for the lack of big-endian memory reads during hashing.     */
549 {
550     UWORD iters = num_bytes / bpw;
551     if (bpw == 4) {
552         UINT32 *p = (UINT32 *)buf;
553         do {
554             *p = LOAD_UINT32_REVERSED(p);
555             p++;
556         } while (--iters);
557     } else if (bpw == 8) {
558         UINT32 *p = (UINT32 *)buf;
559         UINT32 t;
560         do {
561             t = LOAD_UINT32_REVERSED(p+1);
562             p[1] = LOAD_UINT32_REVERSED(p);
563             p[0] = t;
564             p += 2;
565         } while (--iters);
566     }
567 }
568 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
569 #else
570 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
571 #endif
572 
573 /* ---------------------------------------------------------------------- */
574 
575 static void nh_reset(nh_ctx *hc)
576 /* Reset nh_ctx to ready for hashing of new data */
577 {
578     hc->bytes_hashed = 0;
579     hc->next_data_empty = 0;
580     hc->state[0] = 0;
581 #if (UMAC_OUTPUT_LEN >= 8)
582     hc->state[1] = 0;
583 #endif
584 #if (UMAC_OUTPUT_LEN >= 12)
585     hc->state[2] = 0;
586 #endif
587 #if (UMAC_OUTPUT_LEN == 16)
588     hc->state[3] = 0;
589 #endif
590 
591 }
592 
593 /* ---------------------------------------------------------------------- */
594 
595 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
596 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
597 {
598     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
599     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
600     nh_reset(hc);
601 }
602 
603 /* ---------------------------------------------------------------------- */
604 
605 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
606 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
607 /* even multiple of HASH_BUF_BYTES.                                       */
608 {
609     UINT32 i,j;
610 
611     j = hc->next_data_empty;
612     if ((j + nbytes) >= HASH_BUF_BYTES) {
613         if (j) {
614             i = HASH_BUF_BYTES - j;
615             memcpy(hc->data+j, buf, i);
616             nh_transform(hc,hc->data,HASH_BUF_BYTES);
617             nbytes -= i;
618             buf += i;
619             hc->bytes_hashed += HASH_BUF_BYTES;
620         }
621         if (nbytes >= HASH_BUF_BYTES) {
622             i = nbytes & ~(HASH_BUF_BYTES - 1);
623             nh_transform(hc, buf, i);
624             nbytes -= i;
625             buf += i;
626             hc->bytes_hashed += i;
627         }
628         j = 0;
629     }
630     memcpy(hc->data + j, buf, nbytes);
631     hc->next_data_empty = j + nbytes;
632 }
633 
634 /* ---------------------------------------------------------------------- */
635 
636 static void zero_pad(UINT8 *p, int nbytes)
637 {
638 /* Write "nbytes" of zeroes, beginning at "p" */
639     if (nbytes >= (int)sizeof(UWORD)) {
640         while ((ptrdiff_t)p % sizeof(UWORD)) {
641             *p = 0;
642             nbytes--;
643             p++;
644         }
645         while (nbytes >= (int)sizeof(UWORD)) {
646             *(UWORD *)p = 0;
647             nbytes -= sizeof(UWORD);
648             p += sizeof(UWORD);
649         }
650     }
651     while (nbytes) {
652         *p = 0;
653         nbytes--;
654         p++;
655     }
656 }
657 
658 /* ---------------------------------------------------------------------- */
659 
660 static void nh_final(nh_ctx *hc, UINT8 *result)
661 /* After passing some number of data buffers to nh_update() for integration
662  * into an NH context, nh_final is called to produce a hash result. If any
663  * bytes are in the buffer hc->data, incorporate them into the
664  * NH context. Finally, add into the NH accumulation "state" the total number
665  * of bits hashed. The resulting numbers are written to the buffer "result".
666  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
667  */
668 {
669     int nh_len, nbits;
670 
671     if (hc->next_data_empty != 0) {
672         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
673                                                 ~(L1_PAD_BOUNDARY - 1));
674         zero_pad(hc->data + hc->next_data_empty,
675                                           nh_len - hc->next_data_empty);
676         nh_transform(hc, hc->data, nh_len);
677         hc->bytes_hashed += hc->next_data_empty;
678     } else if (hc->bytes_hashed == 0) {
679     	nh_len = L1_PAD_BOUNDARY;
680         zero_pad(hc->data, L1_PAD_BOUNDARY);
681         nh_transform(hc, hc->data, nh_len);
682     }
683 
684     nbits = (hc->bytes_hashed << 3);
685     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
686 #if (UMAC_OUTPUT_LEN >= 8)
687     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
688 #endif
689 #if (UMAC_OUTPUT_LEN >= 12)
690     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
691 #endif
692 #if (UMAC_OUTPUT_LEN == 16)
693     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
694 #endif
695     nh_reset(hc);
696 }
697 
698 /* ---------------------------------------------------------------------- */
699 
700 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
701                UINT32 unpadded_len, UINT8 *result)
702 /* All-in-one nh_update() and nh_final() equivalent.
703  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
704  * well aligned
705  */
706 {
707     UINT32 nbits;
708 
709     /* Initialize the hash state */
710     nbits = (unpadded_len << 3);
711 
712     ((UINT64 *)result)[0] = nbits;
713 #if (UMAC_OUTPUT_LEN >= 8)
714     ((UINT64 *)result)[1] = nbits;
715 #endif
716 #if (UMAC_OUTPUT_LEN >= 12)
717     ((UINT64 *)result)[2] = nbits;
718 #endif
719 #if (UMAC_OUTPUT_LEN == 16)
720     ((UINT64 *)result)[3] = nbits;
721 #endif
722 
723     nh_aux(hc->nh_key, buf, result, padded_len);
724 }
725 
726 /* ---------------------------------------------------------------------- */
727 /* ---------------------------------------------------------------------- */
728 /* ----- Begin UHASH Section -------------------------------------------- */
729 /* ---------------------------------------------------------------------- */
730 /* ---------------------------------------------------------------------- */
731 
732 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
733  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
734  * unless the initial data to be hashed is short. After the polynomial-
735  * layer, an inner-product hash is used to produce the final UHASH output.
736  *
737  * UHASH provides two interfaces, one all-at-once and another where data
738  * buffers are presented sequentially. In the sequential interface, the
739  * UHASH client calls the routine uhash_update() as many times as necessary.
740  * When there is no more data to be fed to UHASH, the client calls
741  * uhash_final() which
742  * calculates the UHASH output. Before beginning another UHASH calculation
743  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
744  * uhash(), is equivalent to the sequence of calls uhash_update() and
745  * uhash_final(); however it is optimized and should be
746  * used whenever the sequential interface is not necessary.
747  *
748  * The routine uhash_init() initializes the uhash_ctx data structure and
749  * must be called once, before any other UHASH routine.
750  */
751 
752 /* ---------------------------------------------------------------------- */
753 /* ----- Constants and uhash_ctx ---------------------------------------- */
754 /* ---------------------------------------------------------------------- */
755 
756 /* ---------------------------------------------------------------------- */
757 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
758 /* ---------------------------------------------------------------------- */
759 
760 /* Primes and masks */
761 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
762 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
763 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
764 
765 
766 /* ---------------------------------------------------------------------- */
767 
768 typedef struct uhash_ctx {
769     nh_ctx hash;                          /* Hash context for L1 NH hash  */
770     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
771     UINT64 poly_accum[STREAMS];           /* poly hash result             */
772     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
773     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
774     UINT32 msg_len;                       /* Total length of data passed  */
775                                           /* to uhash */
776 } uhash_ctx;
777 typedef struct uhash_ctx *uhash_ctx_t;
778 
779 /* ---------------------------------------------------------------------- */
780 
781 
782 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
783  * word at a time. As described in the specification, poly32 and poly64
784  * require keys from special domains. The following implementations exploit
785  * the special domains to avoid overflow. The results are not guaranteed to
786  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
787  * patches any errant values.
788  */
789 
790 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
791 {
792     UINT32 key_hi = (UINT32)(key >> 32),
793            key_lo = (UINT32)key,
794            cur_hi = (UINT32)(cur >> 32),
795            cur_lo = (UINT32)cur,
796            x_lo,
797            x_hi;
798     UINT64 X,T,res;
799 
800     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
801     x_lo = (UINT32)X;
802     x_hi = (UINT32)(X >> 32);
803 
804     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
805 
806     T = ((UINT64)x_lo << 32);
807     res += T;
808     if (res < T)
809         res += 59;
810 
811     res += data;
812     if (res < data)
813         res += 59;
814 
815     return res;
816 }
817 
818 
819 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
820  * implementation does not handle all ramp levels. Because we don't handle
821  * the ramp up to p128 modulus in this implementation, we are limited to
822  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
823  * bytes input to UMAC per tag, ie. 16MB).
824  */
825 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
826 {
827     int i;
828     UINT64 *data=(UINT64*)data_in;
829 
830     for (i = 0; i < STREAMS; i++) {
831         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
832             hc->poly_accum[i] = poly64(hc->poly_accum[i],
833                                        hc->poly_key_8[i], p64 - 1);
834             hc->poly_accum[i] = poly64(hc->poly_accum[i],
835                                        hc->poly_key_8[i], (data[i] - 59));
836         } else {
837             hc->poly_accum[i] = poly64(hc->poly_accum[i],
838                                        hc->poly_key_8[i], data[i]);
839         }
840     }
841 }
842 
843 
844 /* ---------------------------------------------------------------------- */
845 
846 
847 /* The final step in UHASH is an inner-product hash. The poly hash
848  * produces a result not neccesarily WORD_LEN bytes long. The inner-
849  * product hash breaks the polyhash output into 16-bit chunks and
850  * multiplies each with a 36 bit key.
851  */
852 
853 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
854 {
855     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
856     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
857     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
858     t = t + ipkp[3] * (UINT64)(UINT16)(data);
859 
860     return t;
861 }
862 
863 static UINT32 ip_reduce_p36(UINT64 t)
864 {
865 /* Divisionless modular reduction */
866     UINT64 ret;
867 
868     ret = (t & m36) + 5 * (t >> 36);
869     if (ret >= p36)
870         ret -= p36;
871 
872     /* return least significant 32 bits */
873     return (UINT32)(ret);
874 }
875 
876 
877 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
878  * the polyhash stage is skipped and ip_short is applied directly to the
879  * NH output.
880  */
881 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
882 {
883     UINT64 t;
884     UINT64 *nhp = (UINT64 *)nh_res;
885 
886     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
887     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
888 #if (UMAC_OUTPUT_LEN >= 8)
889     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
890     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
891 #endif
892 #if (UMAC_OUTPUT_LEN >= 12)
893     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
894     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
895 #endif
896 #if (UMAC_OUTPUT_LEN == 16)
897     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
898     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
899 #endif
900 }
901 
902 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
903  * the polyhash stage is not skipped and ip_long is applied to the
904  * polyhash output.
905  */
906 static void ip_long(uhash_ctx_t ahc, u_char *res)
907 {
908     int i;
909     UINT64 t;
910 
911     for (i = 0; i < STREAMS; i++) {
912         /* fix polyhash output not in Z_p64 */
913         if (ahc->poly_accum[i] >= p64)
914             ahc->poly_accum[i] -= p64;
915         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
916         STORE_UINT32_BIG((UINT32 *)res+i,
917                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
918     }
919 }
920 
921 
922 /* ---------------------------------------------------------------------- */
923 
924 /* ---------------------------------------------------------------------- */
925 
926 /* Reset uhash context for next hash session */
927 static int uhash_reset(uhash_ctx_t pc)
928 {
929     nh_reset(&pc->hash);
930     pc->msg_len = 0;
931     pc->poly_accum[0] = 1;
932 #if (UMAC_OUTPUT_LEN >= 8)
933     pc->poly_accum[1] = 1;
934 #endif
935 #if (UMAC_OUTPUT_LEN >= 12)
936     pc->poly_accum[2] = 1;
937 #endif
938 #if (UMAC_OUTPUT_LEN == 16)
939     pc->poly_accum[3] = 1;
940 #endif
941     return 1;
942 }
943 
944 /* ---------------------------------------------------------------------- */
945 
946 /* Given a pointer to the internal key needed by kdf() and a uhash context,
947  * initialize the NH context and generate keys needed for poly and inner-
948  * product hashing. All keys are endian adjusted in memory so that native
949  * loads cause correct keys to be in registers during calculation.
950  */
951 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
952 {
953     int i;
954     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
955 
956     /* Zero the entire uhash context */
957     memset(ahc, 0, sizeof(uhash_ctx));
958 
959     /* Initialize the L1 hash */
960     nh_init(&ahc->hash, prf_key);
961 
962     /* Setup L2 hash variables */
963     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
964     for (i = 0; i < STREAMS; i++) {
965         /* Fill keys from the buffer, skipping bytes in the buffer not
966          * used by this implementation. Endian reverse the keys if on a
967          * little-endian computer.
968          */
969         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
970         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
971         /* Mask the 64-bit keys to their special domain */
972         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
973         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
974     }
975 
976     /* Setup L3-1 hash variables */
977     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
978     for (i = 0; i < STREAMS; i++)
979           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
980                                                  4*sizeof(UINT64));
981     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
982                                                   sizeof(ahc->ip_keys));
983     for (i = 0; i < STREAMS*4; i++)
984         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
985 
986     /* Setup L3-2 hash variables    */
987     /* Fill buffer with index 4 key */
988     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
989     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
990                          STREAMS * sizeof(UINT32));
991     explicit_bzero(buf, sizeof(buf));
992 }
993 
994 /* ---------------------------------------------------------------------- */
995 
996 #if 0
997 static uhash_ctx_t uhash_alloc(u_char key[])
998 {
999 /* Allocate memory and force to a 16-byte boundary. */
1000     uhash_ctx_t ctx;
1001     u_char bytes_to_add;
1002     aes_int_key prf_key;
1003 
1004     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1005     if (ctx) {
1006         if (ALLOC_BOUNDARY) {
1007             bytes_to_add = ALLOC_BOUNDARY -
1008                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1009             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1010             *((u_char *)ctx - 1) = bytes_to_add;
1011         }
1012         aes_key_setup(key,prf_key);
1013         uhash_init(ctx, prf_key);
1014     }
1015     return (ctx);
1016 }
1017 #endif
1018 
1019 /* ---------------------------------------------------------------------- */
1020 
1021 #if 0
1022 static int uhash_free(uhash_ctx_t ctx)
1023 {
1024 /* Free memory allocated by uhash_alloc */
1025     u_char bytes_to_sub;
1026 
1027     if (ctx) {
1028         if (ALLOC_BOUNDARY) {
1029             bytes_to_sub = *((u_char *)ctx - 1);
1030             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1031         }
1032         free(ctx);
1033     }
1034     return (1);
1035 }
1036 #endif
1037 /* ---------------------------------------------------------------------- */
1038 
1039 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1040 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1041  * hash each one with NH, calling the polyhash on each NH output.
1042  */
1043 {
1044     UWORD bytes_hashed, bytes_remaining;
1045     UINT64 result_buf[STREAMS];
1046     UINT8 *nh_result = (UINT8 *)&result_buf;
1047 
1048     if (ctx->msg_len + len <= L1_KEY_LEN) {
1049         nh_update(&ctx->hash, (const UINT8 *)input, len);
1050         ctx->msg_len += len;
1051     } else {
1052 
1053          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1054          if (ctx->msg_len == L1_KEY_LEN)
1055              bytes_hashed = L1_KEY_LEN;
1056 
1057          if (bytes_hashed + len >= L1_KEY_LEN) {
1058 
1059              /* If some bytes have been passed to the hash function      */
1060              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1061              /* bytes to complete the current nh_block.                  */
1062              if (bytes_hashed) {
1063                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1064                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1065                  nh_final(&ctx->hash, nh_result);
1066                  ctx->msg_len += bytes_remaining;
1067                  poly_hash(ctx,(UINT32 *)nh_result);
1068                  len -= bytes_remaining;
1069                  input += bytes_remaining;
1070              }
1071 
1072              /* Hash directly from input stream if enough bytes */
1073              while (len >= L1_KEY_LEN) {
1074                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1075                                    L1_KEY_LEN, nh_result);
1076                  ctx->msg_len += L1_KEY_LEN;
1077                  len -= L1_KEY_LEN;
1078                  input += L1_KEY_LEN;
1079                  poly_hash(ctx,(UINT32 *)nh_result);
1080              }
1081          }
1082 
1083          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1084          if (len) {
1085              nh_update(&ctx->hash, (const UINT8 *)input, len);
1086              ctx->msg_len += len;
1087          }
1088      }
1089 
1090     return (1);
1091 }
1092 
1093 /* ---------------------------------------------------------------------- */
1094 
1095 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1096 /* Incorporate any pending data, pad, and generate tag */
1097 {
1098     UINT64 result_buf[STREAMS];
1099     UINT8 *nh_result = (UINT8 *)&result_buf;
1100 
1101     if (ctx->msg_len > L1_KEY_LEN) {
1102         if (ctx->msg_len % L1_KEY_LEN) {
1103             nh_final(&ctx->hash, nh_result);
1104             poly_hash(ctx,(UINT32 *)nh_result);
1105         }
1106         ip_long(ctx, res);
1107     } else {
1108         nh_final(&ctx->hash, nh_result);
1109         ip_short(ctx,nh_result, res);
1110     }
1111     uhash_reset(ctx);
1112     return (1);
1113 }
1114 
1115 /* ---------------------------------------------------------------------- */
1116 
1117 #if 0
1118 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1119 /* assumes that msg is in a writable buffer of length divisible by */
1120 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1121 {
1122     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1123     UINT32 nh_len;
1124     int extra_zeroes_needed;
1125 
1126     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1127      * the polyhash.
1128      */
1129     if (len <= L1_KEY_LEN) {
1130     	if (len == 0)                  /* If zero length messages will not */
1131     		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1132     	else
1133         	nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1134         extra_zeroes_needed = nh_len - len;
1135         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1136         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1137         ip_short(ahc,nh_result, res);
1138     } else {
1139         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1140          * output to poly_hash().
1141          */
1142         do {
1143             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1144             poly_hash(ahc,(UINT32 *)nh_result);
1145             len -= L1_KEY_LEN;
1146             msg += L1_KEY_LEN;
1147         } while (len >= L1_KEY_LEN);
1148         if (len) {
1149             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1150             extra_zeroes_needed = nh_len - len;
1151             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1152             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1153             poly_hash(ahc,(UINT32 *)nh_result);
1154         }
1155 
1156         ip_long(ahc, res);
1157     }
1158 
1159     uhash_reset(ahc);
1160     return 1;
1161 }
1162 #endif
1163 
1164 /* ---------------------------------------------------------------------- */
1165 /* ---------------------------------------------------------------------- */
1166 /* ----- Begin UMAC Section --------------------------------------------- */
1167 /* ---------------------------------------------------------------------- */
1168 /* ---------------------------------------------------------------------- */
1169 
1170 /* The UMAC interface has two interfaces, an all-at-once interface where
1171  * the entire message to be authenticated is passed to UMAC in one buffer,
1172  * and a sequential interface where the message is presented a little at a
1173  * time. The all-at-once is more optimaized than the sequential version and
1174  * should be preferred when the sequential interface is not required.
1175  */
1176 struct umac_ctx {
1177     uhash_ctx hash;          /* Hash function for message compression    */
1178     pdf_ctx pdf;             /* PDF for hashed output                    */
1179     void *free_ptr;          /* Address to free this struct via          */
1180 } umac_ctx;
1181 
1182 /* ---------------------------------------------------------------------- */
1183 
1184 #if 0
1185 int umac_reset(struct umac_ctx *ctx)
1186 /* Reset the hash function to begin a new authentication.        */
1187 {
1188     uhash_reset(&ctx->hash);
1189     return (1);
1190 }
1191 #endif
1192 
1193 /* ---------------------------------------------------------------------- */
1194 
1195 int umac_delete(struct umac_ctx *ctx)
1196 /* Deallocate the ctx structure */
1197 {
1198     if (ctx) {
1199         if (ALLOC_BOUNDARY)
1200             ctx = (struct umac_ctx *)ctx->free_ptr;
1201         explicit_bzero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY);
1202         free(ctx);
1203     }
1204     return (1);
1205 }
1206 
1207 /* ---------------------------------------------------------------------- */
1208 
1209 struct umac_ctx *umac_new(const u_char key[])
1210 /* Dynamically allocate a umac_ctx struct, initialize variables,
1211  * generate subkeys from key. Align to 16-byte boundary.
1212  */
1213 {
1214     struct umac_ctx *ctx, *octx;
1215     size_t bytes_to_add;
1216     aes_int_key prf_key;
1217 
1218     octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1219     if (ctx) {
1220         if (ALLOC_BOUNDARY) {
1221             bytes_to_add = ALLOC_BOUNDARY -
1222                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1223             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1224         }
1225         ctx->free_ptr = octx;
1226         aes_key_setup(key, prf_key);
1227         pdf_init(&ctx->pdf, prf_key);
1228         uhash_init(&ctx->hash, prf_key);
1229         explicit_bzero(prf_key, sizeof(prf_key));
1230     }
1231 
1232     return (ctx);
1233 }
1234 
1235 /* ---------------------------------------------------------------------- */
1236 
1237 int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1238 /* Incorporate any pending data, pad, and generate tag */
1239 {
1240     uhash_final(&ctx->hash, (u_char *)tag);
1241     pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1242 
1243     return (1);
1244 }
1245 
1246 /* ---------------------------------------------------------------------- */
1247 
1248 int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1249 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1250 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1251 /* output buffer is full.                                                 */
1252 {
1253     uhash_update(&ctx->hash, input, len);
1254     return (1);
1255 }
1256 
1257 /* ---------------------------------------------------------------------- */
1258 
1259 #if 0
1260 int umac(struct umac_ctx *ctx, u_char *input,
1261          long len, u_char tag[],
1262          u_char nonce[8])
1263 /* All-in-one version simply calls umac_update() and umac_final().        */
1264 {
1265     uhash(&ctx->hash, input, len, (u_char *)tag);
1266     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1267 
1268     return (1);
1269 }
1270 #endif
1271 
1272 /* ---------------------------------------------------------------------- */
1273 /* ---------------------------------------------------------------------- */
1274 /* ----- End UMAC Section ----------------------------------------------- */
1275 /* ---------------------------------------------------------------------- */
1276 /* ---------------------------------------------------------------------- */
1277