xref: /openssh-portable/umac.c (revision d081f017)
1 /* $OpenBSD: umac.c,v 1.20 2020/03/13 03:17:07 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 license 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 authenticated encryption         */
69 
70 /* ---------------------------------------------------------------------- */
71 /* -- Global Includes --------------------------------------------------- */
72 /* ---------------------------------------------------------------------- */
73 
74 #include "includes.h"
75 #include <sys/types.h>
76 #include <string.h>
77 #include <stdarg.h>
78 #include <stdio.h>
79 #include <stdlib.h>
80 #include <stddef.h>
81 
82 #include "xmalloc.h"
83 #include "umac.h"
84 #include "misc.h"
85 
86 /* ---------------------------------------------------------------------- */
87 /* --- Primitive Data Types ---                                           */
88 /* ---------------------------------------------------------------------- */
89 
90 /* The following assumptions may need change on your system */
91 typedef u_int8_t	UINT8;  /* 1 byte   */
92 typedef u_int16_t	UINT16; /* 2 byte   */
93 typedef u_int32_t	UINT32; /* 4 byte   */
94 typedef u_int64_t	UINT64; /* 8 bytes  */
95 typedef unsigned int	UWORD;  /* Register */
96 
97 /* ---------------------------------------------------------------------- */
98 /* --- Constants -------------------------------------------------------- */
99 /* ---------------------------------------------------------------------- */
100 
101 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
102 
103 /* Message "words" are read from memory in an endian-specific manner.     */
104 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
105 /* be set true if the host computer is little-endian.                     */
106 
107 #if BYTE_ORDER == LITTLE_ENDIAN
108 #define __LITTLE_ENDIAN__ 1
109 #else
110 #define __LITTLE_ENDIAN__ 0
111 #endif
112 
113 /* ---------------------------------------------------------------------- */
114 /* ---------------------------------------------------------------------- */
115 /* ----- Architecture Specific ------------------------------------------ */
116 /* ---------------------------------------------------------------------- */
117 /* ---------------------------------------------------------------------- */
118 
119 
120 /* ---------------------------------------------------------------------- */
121 /* ---------------------------------------------------------------------- */
122 /* ----- Primitive Routines --------------------------------------------- */
123 /* ---------------------------------------------------------------------- */
124 /* ---------------------------------------------------------------------- */
125 
126 
127 /* ---------------------------------------------------------------------- */
128 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
129 /* ---------------------------------------------------------------------- */
130 
131 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
132 
133 /* ---------------------------------------------------------------------- */
134 /* --- Endian Conversion --- Forcing assembly on some platforms           */
135 /* ---------------------------------------------------------------------- */
136 
137 #if (__LITTLE_ENDIAN__)
138 #define LOAD_UINT32_REVERSED(p)		get_u32(p)
139 #define STORE_UINT32_REVERSED(p,v)	put_u32(p,v)
140 #else
141 #define LOAD_UINT32_REVERSED(p)		get_u32_le(p)
142 #define STORE_UINT32_REVERSED(p,v)	put_u32_le(p,v)
143 #endif
144 
145 #define LOAD_UINT32_LITTLE(p)		(get_u32_le(p))
146 #define STORE_UINT32_BIG(p,v)		put_u32(p, v)
147 
148 /* ---------------------------------------------------------------------- */
149 /* ---------------------------------------------------------------------- */
150 /* ----- Begin KDF & PDF Section ---------------------------------------- */
151 /* ---------------------------------------------------------------------- */
152 /* ---------------------------------------------------------------------- */
153 
154 /* UMAC uses AES with 16 byte block and key lengths */
155 #define AES_BLOCK_LEN  16
156 
157 /* OpenSSL's AES */
158 #ifdef WITH_OPENSSL
159 #include "openbsd-compat/openssl-compat.h"
160 #ifndef USE_BUILTIN_RIJNDAEL
161 # include <openssl/aes.h>
162 #endif
163 typedef AES_KEY aes_int_key[1];
164 #define aes_encryption(in,out,int_key)                  \
165   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
166 #define aes_key_setup(key,int_key)                      \
167   AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key)
168 #else
169 #include "rijndael.h"
170 #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6)
171 typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4];	/* AES internal */
172 #define aes_encryption(in,out,int_key) \
173   rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out))
174 #define aes_key_setup(key,int_key) \
175   rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \
176   UMAC_KEY_LEN*8)
177 #endif
178 
179 /* The user-supplied UMAC key is stretched using AES in a counter
180  * mode to supply all random bits needed by UMAC. The kdf function takes
181  * an AES internal key representation 'key' and writes a stream of
182  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
183  * 'ndx' causes a distinct byte stream.
184  */
kdf(void * bufp,aes_int_key key,UINT8 ndx,int nbytes)185 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
186 {
187     UINT8 in_buf[AES_BLOCK_LEN] = {0};
188     UINT8 out_buf[AES_BLOCK_LEN];
189     UINT8 *dst_buf = (UINT8 *)bufp;
190     int i;
191 
192     /* Setup the initial value */
193     in_buf[AES_BLOCK_LEN-9] = ndx;
194     in_buf[AES_BLOCK_LEN-1] = i = 1;
195 
196     while (nbytes >= AES_BLOCK_LEN) {
197         aes_encryption(in_buf, out_buf, key);
198         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
199         in_buf[AES_BLOCK_LEN-1] = ++i;
200         nbytes -= AES_BLOCK_LEN;
201         dst_buf += AES_BLOCK_LEN;
202     }
203     if (nbytes) {
204         aes_encryption(in_buf, out_buf, key);
205         memcpy(dst_buf,out_buf,nbytes);
206     }
207     explicit_bzero(in_buf, sizeof(in_buf));
208     explicit_bzero(out_buf, sizeof(out_buf));
209 }
210 
211 /* The final UHASH result is XOR'd with the output of a pseudorandom
212  * function. Here, we use AES to generate random output and
213  * xor the appropriate bytes depending on the last bits of nonce.
214  * This scheme is optimized for sequential, increasing big-endian nonces.
215  */
216 
217 typedef struct {
218     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
219     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
220     aes_int_key prf_key;         /* Expanded AES key for PDF          */
221 } pdf_ctx;
222 
pdf_init(pdf_ctx * pc,aes_int_key prf_key)223 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
224 {
225     UINT8 buf[UMAC_KEY_LEN];
226 
227     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
228     aes_key_setup(buf, pc->prf_key);
229 
230     /* Initialize pdf and cache */
231     memset(pc->nonce, 0, sizeof(pc->nonce));
232     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
233     explicit_bzero(buf, sizeof(buf));
234 }
235 
pdf_gen_xor(pdf_ctx * pc,const UINT8 nonce[8],UINT8 buf[8])236 static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8])
237 {
238     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
239      * of the AES output. If last time around we returned the ndx-1st
240      * element, then we may have the result in the cache already.
241      */
242 
243 #if (UMAC_OUTPUT_LEN == 4)
244 #define LOW_BIT_MASK 3
245 #elif (UMAC_OUTPUT_LEN == 8)
246 #define LOW_BIT_MASK 1
247 #elif (UMAC_OUTPUT_LEN > 8)
248 #define LOW_BIT_MASK 0
249 #endif
250     union {
251         UINT8 tmp_nonce_lo[4];
252         UINT32 align;
253     } t;
254 #if LOW_BIT_MASK != 0
255     int ndx = nonce[7] & LOW_BIT_MASK;
256 #endif
257     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
258     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
259 
260     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
261          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
262     {
263         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
264         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
265         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
266     }
267 
268 #if (UMAC_OUTPUT_LEN == 4)
269     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
270 #elif (UMAC_OUTPUT_LEN == 8)
271     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
272 #elif (UMAC_OUTPUT_LEN == 12)
273     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
274     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
275 #elif (UMAC_OUTPUT_LEN == 16)
276     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
277     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
278 #endif
279 }
280 
281 /* ---------------------------------------------------------------------- */
282 /* ---------------------------------------------------------------------- */
283 /* ----- Begin NH Hash Section ------------------------------------------ */
284 /* ---------------------------------------------------------------------- */
285 /* ---------------------------------------------------------------------- */
286 
287 /* The NH-based hash functions used in UMAC are described in the UMAC paper
288  * and specification, both of which can be found at the UMAC website.
289  * The interface to this implementation has two
290  * versions, one expects the entire message being hashed to be passed
291  * in a single buffer and returns the hash result immediately. The second
292  * allows the message to be passed in a sequence of buffers. In the
293  * muliple-buffer interface, the client calls the routine nh_update() as
294  * many times as necessary. When there is no more data to be fed to the
295  * hash, the client calls nh_final() which calculates the hash output.
296  * Before beginning another hash calculation the nh_reset() routine
297  * must be called. The single-buffer routine, nh(), is equivalent to
298  * the sequence of calls nh_update() and nh_final(); however it is
299  * optimized and should be preferred whenever the multiple-buffer interface
300  * is not necessary. When using either interface, it is the client's
301  * responsibility to pass no more than L1_KEY_LEN bytes per hash result.
302  *
303  * The routine nh_init() initializes the nh_ctx data structure and
304  * must be called once, before any other PDF routine.
305  */
306 
307  /* The "nh_aux" routines do the actual NH hashing work. They
308   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
309   * produce output for all STREAMS NH iterations in one call,
310   * allowing the parallel implementation of the streams.
311   */
312 
313 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
314 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
315 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
316 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
317 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
318 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
319 
320 typedef struct {
321     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
322     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
323     int next_data_empty;    /* Bookkeeping variable for data buffer.     */
324     int bytes_hashed;       /* Bytes (out of L1_KEY_LEN) incorporated.   */
325     UINT64 state[STREAMS];               /* on-line state     */
326 } nh_ctx;
327 
328 
329 #if (UMAC_OUTPUT_LEN == 4)
330 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)331 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
332 /* NH hashing primitive. Previous (partial) hash result is loaded and
333 * then stored via hp pointer. The length of the data pointed at by "dp",
334 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
335 * is expected to be endian compensated in memory at key setup.
336 */
337 {
338     UINT64 h;
339     UWORD c = dlen / 32;
340     UINT32 *k = (UINT32 *)kp;
341     const UINT32 *d = (const UINT32 *)dp;
342     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
343     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
344 
345     h = *((UINT64 *)hp);
346     do {
347         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
348         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
349         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
350         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
351         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
352         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
353         h += MUL64((k0 + d0), (k4 + d4));
354         h += MUL64((k1 + d1), (k5 + d5));
355         h += MUL64((k2 + d2), (k6 + d6));
356         h += MUL64((k3 + d3), (k7 + d7));
357 
358         d += 8;
359         k += 8;
360     } while (--c);
361   *((UINT64 *)hp) = h;
362 }
363 
364 #elif (UMAC_OUTPUT_LEN == 8)
365 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)366 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
367 /* Same as previous nh_aux, but two streams are handled in one pass,
368  * reading and writing 16 bytes of hash-state per call.
369  */
370 {
371   UINT64 h1,h2;
372   UWORD c = dlen / 32;
373   UINT32 *k = (UINT32 *)kp;
374   const UINT32 *d = (const UINT32 *)dp;
375   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
376   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
377         k8,k9,k10,k11;
378 
379   h1 = *((UINT64 *)hp);
380   h2 = *((UINT64 *)hp + 1);
381   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
382   do {
383     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
384     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
385     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
386     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
387     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
388     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
389 
390     h1 += MUL64((k0 + d0), (k4 + d4));
391     h2 += MUL64((k4 + d0), (k8 + d4));
392 
393     h1 += MUL64((k1 + d1), (k5 + d5));
394     h2 += MUL64((k5 + d1), (k9 + d5));
395 
396     h1 += MUL64((k2 + d2), (k6 + d6));
397     h2 += MUL64((k6 + d2), (k10 + d6));
398 
399     h1 += MUL64((k3 + d3), (k7 + d7));
400     h2 += MUL64((k7 + d3), (k11 + d7));
401 
402     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
403 
404     d += 8;
405     k += 8;
406   } while (--c);
407   ((UINT64 *)hp)[0] = h1;
408   ((UINT64 *)hp)[1] = h2;
409 }
410 
411 #elif (UMAC_OUTPUT_LEN == 12)
412 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)413 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
414 /* Same as previous nh_aux, but two streams are handled in one pass,
415  * reading and writing 24 bytes of hash-state per call.
416 */
417 {
418     UINT64 h1,h2,h3;
419     UWORD c = dlen / 32;
420     UINT32 *k = (UINT32 *)kp;
421     const UINT32 *d = (const UINT32 *)dp;
422     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
423     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
424         k8,k9,k10,k11,k12,k13,k14,k15;
425 
426     h1 = *((UINT64 *)hp);
427     h2 = *((UINT64 *)hp + 1);
428     h3 = *((UINT64 *)hp + 2);
429     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
430     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
431     do {
432         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
433         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
434         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
435         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
436         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
437         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
438 
439         h1 += MUL64((k0 + d0), (k4 + d4));
440         h2 += MUL64((k4 + d0), (k8 + d4));
441         h3 += MUL64((k8 + d0), (k12 + d4));
442 
443         h1 += MUL64((k1 + d1), (k5 + d5));
444         h2 += MUL64((k5 + d1), (k9 + d5));
445         h3 += MUL64((k9 + d1), (k13 + d5));
446 
447         h1 += MUL64((k2 + d2), (k6 + d6));
448         h2 += MUL64((k6 + d2), (k10 + d6));
449         h3 += MUL64((k10 + d2), (k14 + d6));
450 
451         h1 += MUL64((k3 + d3), (k7 + d7));
452         h2 += MUL64((k7 + d3), (k11 + d7));
453         h3 += MUL64((k11 + d3), (k15 + d7));
454 
455         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
456         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
457 
458         d += 8;
459         k += 8;
460     } while (--c);
461     ((UINT64 *)hp)[0] = h1;
462     ((UINT64 *)hp)[1] = h2;
463     ((UINT64 *)hp)[2] = h3;
464 }
465 
466 #elif (UMAC_OUTPUT_LEN == 16)
467 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)468 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
469 /* Same as previous nh_aux, but two streams are handled in one pass,
470  * reading and writing 24 bytes of hash-state per call.
471 */
472 {
473     UINT64 h1,h2,h3,h4;
474     UWORD c = dlen / 32;
475     UINT32 *k = (UINT32 *)kp;
476     const UINT32 *d = (const UINT32 *)dp;
477     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
478     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
479         k8,k9,k10,k11,k12,k13,k14,k15,
480         k16,k17,k18,k19;
481 
482     h1 = *((UINT64 *)hp);
483     h2 = *((UINT64 *)hp + 1);
484     h3 = *((UINT64 *)hp + 2);
485     h4 = *((UINT64 *)hp + 3);
486     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
487     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
488     do {
489         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
490         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
491         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
492         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
493         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
494         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
495         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
496 
497         h1 += MUL64((k0 + d0), (k4 + d4));
498         h2 += MUL64((k4 + d0), (k8 + d4));
499         h3 += MUL64((k8 + d0), (k12 + d4));
500         h4 += MUL64((k12 + d0), (k16 + d4));
501 
502         h1 += MUL64((k1 + d1), (k5 + d5));
503         h2 += MUL64((k5 + d1), (k9 + d5));
504         h3 += MUL64((k9 + d1), (k13 + d5));
505         h4 += MUL64((k13 + d1), (k17 + d5));
506 
507         h1 += MUL64((k2 + d2), (k6 + d6));
508         h2 += MUL64((k6 + d2), (k10 + d6));
509         h3 += MUL64((k10 + d2), (k14 + d6));
510         h4 += MUL64((k14 + d2), (k18 + d6));
511 
512         h1 += MUL64((k3 + d3), (k7 + d7));
513         h2 += MUL64((k7 + d3), (k11 + d7));
514         h3 += MUL64((k11 + d3), (k15 + d7));
515         h4 += MUL64((k15 + d3), (k19 + d7));
516 
517         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
518         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
519         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
520 
521         d += 8;
522         k += 8;
523     } while (--c);
524     ((UINT64 *)hp)[0] = h1;
525     ((UINT64 *)hp)[1] = h2;
526     ((UINT64 *)hp)[2] = h3;
527     ((UINT64 *)hp)[3] = h4;
528 }
529 
530 /* ---------------------------------------------------------------------- */
531 #endif  /* UMAC_OUTPUT_LENGTH */
532 /* ---------------------------------------------------------------------- */
533 
534 
535 /* ---------------------------------------------------------------------- */
536 
nh_transform(nh_ctx * hc,const UINT8 * buf,UINT32 nbytes)537 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
538 /* This function is a wrapper for the primitive NH hash functions. It takes
539  * as argument "hc" the current hash context and a buffer which must be a
540  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
541  * appropriately according to how much message has been hashed already.
542  */
543 {
544     UINT8 *key;
545 
546     key = hc->nh_key + hc->bytes_hashed;
547     nh_aux(key, buf, hc->state, nbytes);
548 }
549 
550 /* ---------------------------------------------------------------------- */
551 
552 #if (__LITTLE_ENDIAN__)
endian_convert(void * buf,UWORD bpw,UINT32 num_bytes)553 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
554 /* We endian convert the keys on little-endian computers to               */
555 /* compensate for the lack of big-endian memory reads during hashing.     */
556 {
557     UWORD iters = num_bytes / bpw;
558     if (bpw == 4) {
559         UINT32 *p = (UINT32 *)buf;
560         do {
561             *p = LOAD_UINT32_REVERSED(p);
562             p++;
563         } while (--iters);
564     } else if (bpw == 8) {
565         UINT32 *p = (UINT32 *)buf;
566         UINT32 t;
567         do {
568             t = LOAD_UINT32_REVERSED(p+1);
569             p[1] = LOAD_UINT32_REVERSED(p);
570             p[0] = t;
571             p += 2;
572         } while (--iters);
573     }
574 }
575 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
576 #else
577 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
578 #endif
579 
580 /* ---------------------------------------------------------------------- */
581 
nh_reset(nh_ctx * hc)582 static void nh_reset(nh_ctx *hc)
583 /* Reset nh_ctx to ready for hashing of new data */
584 {
585     hc->bytes_hashed = 0;
586     hc->next_data_empty = 0;
587     hc->state[0] = 0;
588 #if (UMAC_OUTPUT_LEN >= 8)
589     hc->state[1] = 0;
590 #endif
591 #if (UMAC_OUTPUT_LEN >= 12)
592     hc->state[2] = 0;
593 #endif
594 #if (UMAC_OUTPUT_LEN == 16)
595     hc->state[3] = 0;
596 #endif
597 
598 }
599 
600 /* ---------------------------------------------------------------------- */
601 
nh_init(nh_ctx * hc,aes_int_key prf_key)602 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
603 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
604 {
605     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
606     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
607     nh_reset(hc);
608 }
609 
610 /* ---------------------------------------------------------------------- */
611 
nh_update(nh_ctx * hc,const UINT8 * buf,UINT32 nbytes)612 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
613 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
614 /* even multiple of HASH_BUF_BYTES.                                       */
615 {
616     UINT32 i,j;
617 
618     j = hc->next_data_empty;
619     if ((j + nbytes) >= HASH_BUF_BYTES) {
620         if (j) {
621             i = HASH_BUF_BYTES - j;
622             memcpy(hc->data+j, buf, i);
623             nh_transform(hc,hc->data,HASH_BUF_BYTES);
624             nbytes -= i;
625             buf += i;
626             hc->bytes_hashed += HASH_BUF_BYTES;
627         }
628         if (nbytes >= HASH_BUF_BYTES) {
629             i = nbytes & ~(HASH_BUF_BYTES - 1);
630             nh_transform(hc, buf, i);
631             nbytes -= i;
632             buf += i;
633             hc->bytes_hashed += i;
634         }
635         j = 0;
636     }
637     memcpy(hc->data + j, buf, nbytes);
638     hc->next_data_empty = j + nbytes;
639 }
640 
641 /* ---------------------------------------------------------------------- */
642 
zero_pad(UINT8 * p,int nbytes)643 static void zero_pad(UINT8 *p, int nbytes)
644 {
645 /* Write "nbytes" of zeroes, beginning at "p" */
646     if (nbytes >= (int)sizeof(UWORD)) {
647         while ((ptrdiff_t)p % sizeof(UWORD)) {
648             *p = 0;
649             nbytes--;
650             p++;
651         }
652         while (nbytes >= (int)sizeof(UWORD)) {
653             *(UWORD *)p = 0;
654             nbytes -= sizeof(UWORD);
655             p += sizeof(UWORD);
656         }
657     }
658     while (nbytes) {
659         *p = 0;
660         nbytes--;
661         p++;
662     }
663 }
664 
665 /* ---------------------------------------------------------------------- */
666 
nh_final(nh_ctx * hc,UINT8 * result)667 static void nh_final(nh_ctx *hc, UINT8 *result)
668 /* After passing some number of data buffers to nh_update() for integration
669  * into an NH context, nh_final is called to produce a hash result. If any
670  * bytes are in the buffer hc->data, incorporate them into the
671  * NH context. Finally, add into the NH accumulation "state" the total number
672  * of bits hashed. The resulting numbers are written to the buffer "result".
673  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
674  */
675 {
676     int nh_len, nbits;
677 
678     if (hc->next_data_empty != 0) {
679         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
680                                                 ~(L1_PAD_BOUNDARY - 1));
681         zero_pad(hc->data + hc->next_data_empty,
682                                           nh_len - hc->next_data_empty);
683         nh_transform(hc, hc->data, nh_len);
684         hc->bytes_hashed += hc->next_data_empty;
685     } else if (hc->bytes_hashed == 0) {
686 	nh_len = L1_PAD_BOUNDARY;
687         zero_pad(hc->data, L1_PAD_BOUNDARY);
688         nh_transform(hc, hc->data, nh_len);
689     }
690 
691     nbits = (hc->bytes_hashed << 3);
692     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
693 #if (UMAC_OUTPUT_LEN >= 8)
694     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
695 #endif
696 #if (UMAC_OUTPUT_LEN >= 12)
697     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
698 #endif
699 #if (UMAC_OUTPUT_LEN == 16)
700     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
701 #endif
702     nh_reset(hc);
703 }
704 
705 /* ---------------------------------------------------------------------- */
706 
nh(nh_ctx * hc,const UINT8 * buf,UINT32 padded_len,UINT32 unpadded_len,UINT8 * result)707 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
708                UINT32 unpadded_len, UINT8 *result)
709 /* All-in-one nh_update() and nh_final() equivalent.
710  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
711  * well aligned
712  */
713 {
714     UINT32 nbits;
715 
716     /* Initialize the hash state */
717     nbits = (unpadded_len << 3);
718 
719     ((UINT64 *)result)[0] = nbits;
720 #if (UMAC_OUTPUT_LEN >= 8)
721     ((UINT64 *)result)[1] = nbits;
722 #endif
723 #if (UMAC_OUTPUT_LEN >= 12)
724     ((UINT64 *)result)[2] = nbits;
725 #endif
726 #if (UMAC_OUTPUT_LEN == 16)
727     ((UINT64 *)result)[3] = nbits;
728 #endif
729 
730     nh_aux(hc->nh_key, buf, result, padded_len);
731 }
732 
733 /* ---------------------------------------------------------------------- */
734 /* ---------------------------------------------------------------------- */
735 /* ----- Begin UHASH Section -------------------------------------------- */
736 /* ---------------------------------------------------------------------- */
737 /* ---------------------------------------------------------------------- */
738 
739 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
740  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
741  * unless the initial data to be hashed is short. After the polynomial-
742  * layer, an inner-product hash is used to produce the final UHASH output.
743  *
744  * UHASH provides two interfaces, one all-at-once and another where data
745  * buffers are presented sequentially. In the sequential interface, the
746  * UHASH client calls the routine uhash_update() as many times as necessary.
747  * When there is no more data to be fed to UHASH, the client calls
748  * uhash_final() which
749  * calculates the UHASH output. Before beginning another UHASH calculation
750  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
751  * uhash(), is equivalent to the sequence of calls uhash_update() and
752  * uhash_final(); however it is optimized and should be
753  * used whenever the sequential interface is not necessary.
754  *
755  * The routine uhash_init() initializes the uhash_ctx data structure and
756  * must be called once, before any other UHASH routine.
757  */
758 
759 /* ---------------------------------------------------------------------- */
760 /* ----- Constants and uhash_ctx ---------------------------------------- */
761 /* ---------------------------------------------------------------------- */
762 
763 /* ---------------------------------------------------------------------- */
764 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
765 /* ---------------------------------------------------------------------- */
766 
767 /* Primes and masks */
768 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
769 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
770 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
771 
772 
773 /* ---------------------------------------------------------------------- */
774 
775 typedef struct uhash_ctx {
776     nh_ctx hash;                          /* Hash context for L1 NH hash  */
777     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
778     UINT64 poly_accum[STREAMS];           /* poly hash result             */
779     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
780     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
781     UINT32 msg_len;                       /* Total length of data passed  */
782                                           /* to uhash */
783 } uhash_ctx;
784 typedef struct uhash_ctx *uhash_ctx_t;
785 
786 /* ---------------------------------------------------------------------- */
787 
788 
789 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
790  * word at a time. As described in the specification, poly32 and poly64
791  * require keys from special domains. The following implementations exploit
792  * the special domains to avoid overflow. The results are not guaranteed to
793  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
794  * patches any errant values.
795  */
796 
poly64(UINT64 cur,UINT64 key,UINT64 data)797 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
798 {
799     UINT32 key_hi = (UINT32)(key >> 32),
800            key_lo = (UINT32)key,
801            cur_hi = (UINT32)(cur >> 32),
802            cur_lo = (UINT32)cur,
803            x_lo,
804            x_hi;
805     UINT64 X,T,res;
806 
807     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
808     x_lo = (UINT32)X;
809     x_hi = (UINT32)(X >> 32);
810 
811     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
812 
813     T = ((UINT64)x_lo << 32);
814     res += T;
815     if (res < T)
816         res += 59;
817 
818     res += data;
819     if (res < data)
820         res += 59;
821 
822     return res;
823 }
824 
825 
826 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
827  * implementation does not handle all ramp levels. Because we don't handle
828  * the ramp up to p128 modulus in this implementation, we are limited to
829  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
830  * bytes input to UMAC per tag, ie. 16MB).
831  */
poly_hash(uhash_ctx_t hc,UINT32 data_in[])832 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
833 {
834     int i;
835     UINT64 *data=(UINT64*)data_in;
836 
837     for (i = 0; i < STREAMS; i++) {
838         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
839             hc->poly_accum[i] = poly64(hc->poly_accum[i],
840                                        hc->poly_key_8[i], p64 - 1);
841             hc->poly_accum[i] = poly64(hc->poly_accum[i],
842                                        hc->poly_key_8[i], (data[i] - 59));
843         } else {
844             hc->poly_accum[i] = poly64(hc->poly_accum[i],
845                                        hc->poly_key_8[i], data[i]);
846         }
847     }
848 }
849 
850 
851 /* ---------------------------------------------------------------------- */
852 
853 
854 /* The final step in UHASH is an inner-product hash. The poly hash
855  * produces a result not necessarily WORD_LEN bytes long. The inner-
856  * product hash breaks the polyhash output into 16-bit chunks and
857  * multiplies each with a 36 bit key.
858  */
859 
ip_aux(UINT64 t,UINT64 * ipkp,UINT64 data)860 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
861 {
862     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
863     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
864     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
865     t = t + ipkp[3] * (UINT64)(UINT16)(data);
866 
867     return t;
868 }
869 
ip_reduce_p36(UINT64 t)870 static UINT32 ip_reduce_p36(UINT64 t)
871 {
872 /* Divisionless modular reduction */
873     UINT64 ret;
874 
875     ret = (t & m36) + 5 * (t >> 36);
876     if (ret >= p36)
877         ret -= p36;
878 
879     /* return least significant 32 bits */
880     return (UINT32)(ret);
881 }
882 
883 
884 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
885  * the polyhash stage is skipped and ip_short is applied directly to the
886  * NH output.
887  */
ip_short(uhash_ctx_t ahc,UINT8 * nh_res,u_char * res)888 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
889 {
890     UINT64 t;
891     UINT64 *nhp = (UINT64 *)nh_res;
892 
893     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
894     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
895 #if (UMAC_OUTPUT_LEN >= 8)
896     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
897     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
898 #endif
899 #if (UMAC_OUTPUT_LEN >= 12)
900     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
901     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
902 #endif
903 #if (UMAC_OUTPUT_LEN == 16)
904     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
905     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
906 #endif
907 }
908 
909 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
910  * the polyhash stage is not skipped and ip_long is applied to the
911  * polyhash output.
912  */
ip_long(uhash_ctx_t ahc,u_char * res)913 static void ip_long(uhash_ctx_t ahc, u_char *res)
914 {
915     int i;
916     UINT64 t;
917 
918     for (i = 0; i < STREAMS; i++) {
919         /* fix polyhash output not in Z_p64 */
920         if (ahc->poly_accum[i] >= p64)
921             ahc->poly_accum[i] -= p64;
922         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
923         STORE_UINT32_BIG((UINT32 *)res+i,
924                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
925     }
926 }
927 
928 
929 /* ---------------------------------------------------------------------- */
930 
931 /* ---------------------------------------------------------------------- */
932 
933 /* Reset uhash context for next hash session */
uhash_reset(uhash_ctx_t pc)934 static int uhash_reset(uhash_ctx_t pc)
935 {
936     nh_reset(&pc->hash);
937     pc->msg_len = 0;
938     pc->poly_accum[0] = 1;
939 #if (UMAC_OUTPUT_LEN >= 8)
940     pc->poly_accum[1] = 1;
941 #endif
942 #if (UMAC_OUTPUT_LEN >= 12)
943     pc->poly_accum[2] = 1;
944 #endif
945 #if (UMAC_OUTPUT_LEN == 16)
946     pc->poly_accum[3] = 1;
947 #endif
948     return 1;
949 }
950 
951 /* ---------------------------------------------------------------------- */
952 
953 /* Given a pointer to the internal key needed by kdf() and a uhash context,
954  * initialize the NH context and generate keys needed for poly and inner-
955  * product hashing. All keys are endian adjusted in memory so that native
956  * loads cause correct keys to be in registers during calculation.
957  */
uhash_init(uhash_ctx_t ahc,aes_int_key prf_key)958 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
959 {
960     int i;
961     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
962 
963     /* Zero the entire uhash context */
964     memset(ahc, 0, sizeof(uhash_ctx));
965 
966     /* Initialize the L1 hash */
967     nh_init(&ahc->hash, prf_key);
968 
969     /* Setup L2 hash variables */
970     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
971     for (i = 0; i < STREAMS; i++) {
972         /* Fill keys from the buffer, skipping bytes in the buffer not
973          * used by this implementation. Endian reverse the keys if on a
974          * little-endian computer.
975          */
976         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
977         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
978         /* Mask the 64-bit keys to their special domain */
979         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
980         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
981     }
982 
983     /* Setup L3-1 hash variables */
984     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
985     for (i = 0; i < STREAMS; i++)
986           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
987                                                  4*sizeof(UINT64));
988     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
989                                                   sizeof(ahc->ip_keys));
990     for (i = 0; i < STREAMS*4; i++)
991         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
992 
993     /* Setup L3-2 hash variables    */
994     /* Fill buffer with index 4 key */
995     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
996     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
997                          STREAMS * sizeof(UINT32));
998     explicit_bzero(buf, sizeof(buf));
999 }
1000 
1001 /* ---------------------------------------------------------------------- */
1002 
1003 #if 0
1004 static uhash_ctx_t uhash_alloc(u_char key[])
1005 {
1006 /* Allocate memory and force to a 16-byte boundary. */
1007     uhash_ctx_t ctx;
1008     u_char bytes_to_add;
1009     aes_int_key prf_key;
1010 
1011     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1012     if (ctx) {
1013         if (ALLOC_BOUNDARY) {
1014             bytes_to_add = ALLOC_BOUNDARY -
1015                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1016             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1017             *((u_char *)ctx - 1) = bytes_to_add;
1018         }
1019         aes_key_setup(key,prf_key);
1020         uhash_init(ctx, prf_key);
1021     }
1022     return (ctx);
1023 }
1024 #endif
1025 
1026 /* ---------------------------------------------------------------------- */
1027 
1028 #if 0
1029 static int uhash_free(uhash_ctx_t ctx)
1030 {
1031 /* Free memory allocated by uhash_alloc */
1032     u_char bytes_to_sub;
1033 
1034     if (ctx) {
1035         if (ALLOC_BOUNDARY) {
1036             bytes_to_sub = *((u_char *)ctx - 1);
1037             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1038         }
1039         free(ctx);
1040     }
1041     return (1);
1042 }
1043 #endif
1044 /* ---------------------------------------------------------------------- */
1045 
uhash_update(uhash_ctx_t ctx,const u_char * input,long len)1046 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1047 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1048  * hash each one with NH, calling the polyhash on each NH output.
1049  */
1050 {
1051     UWORD bytes_hashed, bytes_remaining;
1052     UINT64 result_buf[STREAMS];
1053     UINT8 *nh_result = (UINT8 *)&result_buf;
1054 
1055     if (ctx->msg_len + len <= L1_KEY_LEN) {
1056         nh_update(&ctx->hash, (const UINT8 *)input, len);
1057         ctx->msg_len += len;
1058     } else {
1059 
1060          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1061          if (ctx->msg_len == L1_KEY_LEN)
1062              bytes_hashed = L1_KEY_LEN;
1063 
1064          if (bytes_hashed + len >= L1_KEY_LEN) {
1065 
1066              /* If some bytes have been passed to the hash function      */
1067              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1068              /* bytes to complete the current nh_block.                  */
1069              if (bytes_hashed) {
1070                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1071                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1072                  nh_final(&ctx->hash, nh_result);
1073                  ctx->msg_len += bytes_remaining;
1074                  poly_hash(ctx,(UINT32 *)nh_result);
1075                  len -= bytes_remaining;
1076                  input += bytes_remaining;
1077              }
1078 
1079              /* Hash directly from input stream if enough bytes */
1080              while (len >= L1_KEY_LEN) {
1081                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1082                                    L1_KEY_LEN, nh_result);
1083                  ctx->msg_len += L1_KEY_LEN;
1084                  len -= L1_KEY_LEN;
1085                  input += L1_KEY_LEN;
1086                  poly_hash(ctx,(UINT32 *)nh_result);
1087              }
1088          }
1089 
1090          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1091          if (len) {
1092              nh_update(&ctx->hash, (const UINT8 *)input, len);
1093              ctx->msg_len += len;
1094          }
1095      }
1096 
1097     return (1);
1098 }
1099 
1100 /* ---------------------------------------------------------------------- */
1101 
uhash_final(uhash_ctx_t ctx,u_char * res)1102 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1103 /* Incorporate any pending data, pad, and generate tag */
1104 {
1105     UINT64 result_buf[STREAMS];
1106     UINT8 *nh_result = (UINT8 *)&result_buf;
1107 
1108     if (ctx->msg_len > L1_KEY_LEN) {
1109         if (ctx->msg_len % L1_KEY_LEN) {
1110             nh_final(&ctx->hash, nh_result);
1111             poly_hash(ctx,(UINT32 *)nh_result);
1112         }
1113         ip_long(ctx, res);
1114     } else {
1115         nh_final(&ctx->hash, nh_result);
1116         ip_short(ctx,nh_result, res);
1117     }
1118     uhash_reset(ctx);
1119     return (1);
1120 }
1121 
1122 /* ---------------------------------------------------------------------- */
1123 
1124 #if 0
1125 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1126 /* assumes that msg is in a writable buffer of length divisible by */
1127 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1128 {
1129     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1130     UINT32 nh_len;
1131     int extra_zeroes_needed;
1132 
1133     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1134      * the polyhash.
1135      */
1136     if (len <= L1_KEY_LEN) {
1137 	if (len == 0)                  /* If zero length messages will not */
1138 		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1139 	else
1140 		nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1141         extra_zeroes_needed = nh_len - len;
1142         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1143         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1144         ip_short(ahc,nh_result, res);
1145     } else {
1146         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1147          * output to poly_hash().
1148          */
1149         do {
1150             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1151             poly_hash(ahc,(UINT32 *)nh_result);
1152             len -= L1_KEY_LEN;
1153             msg += L1_KEY_LEN;
1154         } while (len >= L1_KEY_LEN);
1155         if (len) {
1156             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1157             extra_zeroes_needed = nh_len - len;
1158             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1159             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1160             poly_hash(ahc,(UINT32 *)nh_result);
1161         }
1162 
1163         ip_long(ahc, res);
1164     }
1165 
1166     uhash_reset(ahc);
1167     return 1;
1168 }
1169 #endif
1170 
1171 /* ---------------------------------------------------------------------- */
1172 /* ---------------------------------------------------------------------- */
1173 /* ----- Begin UMAC Section --------------------------------------------- */
1174 /* ---------------------------------------------------------------------- */
1175 /* ---------------------------------------------------------------------- */
1176 
1177 /* The UMAC interface has two interfaces, an all-at-once interface where
1178  * the entire message to be authenticated is passed to UMAC in one buffer,
1179  * and a sequential interface where the message is presented a little at a
1180  * time. The all-at-once is more optimaized than the sequential version and
1181  * should be preferred when the sequential interface is not required.
1182  */
1183 struct umac_ctx {
1184     uhash_ctx hash;          /* Hash function for message compression    */
1185     pdf_ctx pdf;             /* PDF for hashed output                    */
1186     void *free_ptr;          /* Address to free this struct via          */
1187 } umac_ctx;
1188 
1189 /* ---------------------------------------------------------------------- */
1190 
1191 #if 0
1192 int umac_reset(struct umac_ctx *ctx)
1193 /* Reset the hash function to begin a new authentication.        */
1194 {
1195     uhash_reset(&ctx->hash);
1196     return (1);
1197 }
1198 #endif
1199 
1200 /* ---------------------------------------------------------------------- */
1201 
umac_delete(struct umac_ctx * ctx)1202 int umac_delete(struct umac_ctx *ctx)
1203 /* Deallocate the ctx structure */
1204 {
1205     if (ctx) {
1206         if (ALLOC_BOUNDARY)
1207             ctx = (struct umac_ctx *)ctx->free_ptr;
1208         freezero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY);
1209     }
1210     return (1);
1211 }
1212 
1213 /* ---------------------------------------------------------------------- */
1214 
umac_new(const u_char key[])1215 struct umac_ctx *umac_new(const u_char key[])
1216 /* Dynamically allocate a umac_ctx struct, initialize variables,
1217  * generate subkeys from key. Align to 16-byte boundary.
1218  */
1219 {
1220     struct umac_ctx *ctx, *octx;
1221     size_t bytes_to_add;
1222     aes_int_key prf_key;
1223 
1224     octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1225     if (ctx) {
1226         if (ALLOC_BOUNDARY) {
1227             bytes_to_add = ALLOC_BOUNDARY -
1228                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1229             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1230         }
1231         ctx->free_ptr = octx;
1232         aes_key_setup(key, prf_key);
1233         pdf_init(&ctx->pdf, prf_key);
1234         uhash_init(&ctx->hash, prf_key);
1235         explicit_bzero(prf_key, sizeof(prf_key));
1236     }
1237 
1238     return (ctx);
1239 }
1240 
1241 /* ---------------------------------------------------------------------- */
1242 
umac_final(struct umac_ctx * ctx,u_char tag[],const u_char nonce[8])1243 int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1244 /* Incorporate any pending data, pad, and generate tag */
1245 {
1246     uhash_final(&ctx->hash, (u_char *)tag);
1247     pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1248 
1249     return (1);
1250 }
1251 
1252 /* ---------------------------------------------------------------------- */
1253 
umac_update(struct umac_ctx * ctx,const u_char * input,long len)1254 int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1255 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1256 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1257 /* output buffer is full.                                                 */
1258 {
1259     uhash_update(&ctx->hash, input, len);
1260     return (1);
1261 }
1262 
1263 /* ---------------------------------------------------------------------- */
1264 
1265 #if 0
1266 int umac(struct umac_ctx *ctx, u_char *input,
1267          long len, u_char tag[],
1268          u_char nonce[8])
1269 /* All-in-one version simply calls umac_update() and umac_final().        */
1270 {
1271     uhash(&ctx->hash, input, len, (u_char *)tag);
1272     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1273 
1274     return (1);
1275 }
1276 #endif
1277 
1278 /* ---------------------------------------------------------------------- */
1279 /* ---------------------------------------------------------------------- */
1280 /* ----- End UMAC Section ----------------------------------------------- */
1281 /* ---------------------------------------------------------------------- */
1282 /* ---------------------------------------------------------------------- */
1283