xref: /openssh-portable/umac.c (revision 001aa554)
1 /* $OpenBSD: umac.c,v 1.17 2018/04/10 00:10:49 djm Exp $ */
2 /* -----------------------------------------------------------------------
3  *
4  * umac.c -- C Implementation UMAC Message Authentication
5  *
6  * Version 0.93b of rfc4418.txt -- 2006 July 18
7  *
8  * For a full description of UMAC message authentication see the UMAC
9  * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac
10  * Please report bugs and suggestions to the UMAC webpage.
11  *
12  * Copyright (c) 1999-2006 Ted Krovetz
13  *
14  * Permission to use, copy, modify, and distribute this software and
15  * its documentation for any purpose and with or without fee, is hereby
16  * granted provided that the above copyright notice appears in all copies
17  * and in supporting documentation, and that the name of the copyright
18  * holder not be used in advertising or publicity pertaining to
19  * distribution of the software without specific, written prior permission.
20  *
21  * Comments should be directed to Ted Krovetz (tdk@acm.org)
22  *
23  * ---------------------------------------------------------------------- */
24 
25  /* ////////////////////// IMPORTANT NOTES /////////////////////////////////
26   *
27   * 1) This version does not work properly on messages larger than 16MB
28   *
29   * 2) If you set the switch to use SSE2, then all data must be 16-byte
30   *    aligned
31   *
32   * 3) When calling the function umac(), it is assumed that msg is in
33   * a writable buffer of length divisible by 32 bytes. The message itself
34   * does not have to fill the entire buffer, but bytes beyond msg may be
35   * zeroed.
36   *
37   * 4) Three free AES implementations are supported by this implementation of
38   * UMAC. Paulo Barreto's version is in the public domain and can be found
39   * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for
40   * "Barreto"). The only two files needed are rijndael-alg-fst.c and
41   * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU
42   * Public lisence at http://fp.gladman.plus.com/AES/index.htm. It
43   * includes a fast IA-32 assembly version. The OpenSSL crypo library is
44   * the third.
45   *
46   * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes
47   * produced under gcc with optimizations set -O3 or higher. Dunno why.
48   *
49   /////////////////////////////////////////////////////////////////////// */
50 
51 /* ---------------------------------------------------------------------- */
52 /* --- User Switches ---------------------------------------------------- */
53 /* ---------------------------------------------------------------------- */
54 
55 #ifndef UMAC_OUTPUT_LEN
56 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
57 #endif
58 
59 #if UMAC_OUTPUT_LEN != 4 && UMAC_OUTPUT_LEN != 8 && \
60     UMAC_OUTPUT_LEN != 12 && UMAC_OUTPUT_LEN != 16
61 # error UMAC_OUTPUT_LEN must be defined to 4, 8, 12 or 16
62 #endif
63 
64 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
65 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
66 /* #define SSE2                0  Is SSE2 is available?                   */
67 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
68 /* #define UMAC_AE_SUPPORT     0  Enable authenticated encryption         */
69 
70 /* ---------------------------------------------------------------------- */
71 /* -- Global Includes --------------------------------------------------- */
72 /* ---------------------------------------------------------------------- */
73 
74 #include "includes.h"
75 #include <sys/types.h>
76 #include <string.h>
77 #include <stdio.h>
78 #include <stdlib.h>
79 #include <stddef.h>
80 
81 #include "xmalloc.h"
82 #include "umac.h"
83 #include "misc.h"
84 
85 /* ---------------------------------------------------------------------- */
86 /* --- Primitive Data Types ---                                           */
87 /* ---------------------------------------------------------------------- */
88 
89 /* The following assumptions may need change on your system */
90 typedef u_int8_t	UINT8;  /* 1 byte   */
91 typedef u_int16_t	UINT16; /* 2 byte   */
92 typedef u_int32_t	UINT32; /* 4 byte   */
93 typedef u_int64_t	UINT64; /* 8 bytes  */
94 typedef unsigned int	UWORD;  /* Register */
95 
96 /* ---------------------------------------------------------------------- */
97 /* --- Constants -------------------------------------------------------- */
98 /* ---------------------------------------------------------------------- */
99 
100 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
101 
102 /* Message "words" are read from memory in an endian-specific manner.     */
103 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
104 /* be set true if the host computer is little-endian.                     */
105 
106 #if BYTE_ORDER == LITTLE_ENDIAN
107 #define __LITTLE_ENDIAN__ 1
108 #else
109 #define __LITTLE_ENDIAN__ 0
110 #endif
111 
112 /* ---------------------------------------------------------------------- */
113 /* ---------------------------------------------------------------------- */
114 /* ----- Architecture Specific ------------------------------------------ */
115 /* ---------------------------------------------------------------------- */
116 /* ---------------------------------------------------------------------- */
117 
118 
119 /* ---------------------------------------------------------------------- */
120 /* ---------------------------------------------------------------------- */
121 /* ----- Primitive Routines --------------------------------------------- */
122 /* ---------------------------------------------------------------------- */
123 /* ---------------------------------------------------------------------- */
124 
125 
126 /* ---------------------------------------------------------------------- */
127 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
128 /* ---------------------------------------------------------------------- */
129 
130 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
131 
132 /* ---------------------------------------------------------------------- */
133 /* --- Endian Conversion --- Forcing assembly on some platforms           */
134 /* ---------------------------------------------------------------------- */
135 
136 #if (__LITTLE_ENDIAN__)
137 #define LOAD_UINT32_REVERSED(p)		get_u32(p)
138 #define STORE_UINT32_REVERSED(p,v)	put_u32(p,v)
139 #else
140 #define LOAD_UINT32_REVERSED(p)		get_u32_le(p)
141 #define STORE_UINT32_REVERSED(p,v)	put_u32_le(p,v)
142 #endif
143 
144 #define LOAD_UINT32_LITTLE(p)		(get_u32_le(p))
145 #define STORE_UINT32_BIG(p,v)		put_u32(p, v)
146 
147 /* ---------------------------------------------------------------------- */
148 /* ---------------------------------------------------------------------- */
149 /* ----- Begin KDF & PDF Section ---------------------------------------- */
150 /* ---------------------------------------------------------------------- */
151 /* ---------------------------------------------------------------------- */
152 
153 /* UMAC uses AES with 16 byte block and key lengths */
154 #define AES_BLOCK_LEN  16
155 
156 /* OpenSSL's AES */
157 #ifdef WITH_OPENSSL
158 #include "openbsd-compat/openssl-compat.h"
159 #ifndef USE_BUILTIN_RIJNDAEL
160 # include <openssl/aes.h>
161 #endif
162 typedef AES_KEY aes_int_key[1];
163 #define aes_encryption(in,out,int_key)                  \
164   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
165 #define aes_key_setup(key,int_key)                      \
166   AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key)
167 #else
168 #include "rijndael.h"
169 #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6)
170 typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4];	/* AES internal */
171 #define aes_encryption(in,out,int_key) \
172   rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out))
173 #define aes_key_setup(key,int_key) \
174   rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \
175   UMAC_KEY_LEN*8)
176 #endif
177 
178 /* The user-supplied UMAC key is stretched using AES in a counter
179  * mode to supply all random bits needed by UMAC. The kdf function takes
180  * an AES internal key representation 'key' and writes a stream of
181  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
182  * 'ndx' causes a distinct byte stream.
183  */
kdf(void * bufp,aes_int_key key,UINT8 ndx,int nbytes)184 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
185 {
186     UINT8 in_buf[AES_BLOCK_LEN] = {0};
187     UINT8 out_buf[AES_BLOCK_LEN];
188     UINT8 *dst_buf = (UINT8 *)bufp;
189     int i;
190 
191     /* Setup the initial value */
192     in_buf[AES_BLOCK_LEN-9] = ndx;
193     in_buf[AES_BLOCK_LEN-1] = i = 1;
194 
195     while (nbytes >= AES_BLOCK_LEN) {
196         aes_encryption(in_buf, out_buf, key);
197         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
198         in_buf[AES_BLOCK_LEN-1] = ++i;
199         nbytes -= AES_BLOCK_LEN;
200         dst_buf += AES_BLOCK_LEN;
201     }
202     if (nbytes) {
203         aes_encryption(in_buf, out_buf, key);
204         memcpy(dst_buf,out_buf,nbytes);
205     }
206     explicit_bzero(in_buf, sizeof(in_buf));
207     explicit_bzero(out_buf, sizeof(out_buf));
208 }
209 
210 /* The final UHASH result is XOR'd with the output of a pseudorandom
211  * function. Here, we use AES to generate random output and
212  * xor the appropriate bytes depending on the last bits of nonce.
213  * This scheme is optimized for sequential, increasing big-endian nonces.
214  */
215 
216 typedef struct {
217     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
218     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
219     aes_int_key prf_key;         /* Expanded AES key for PDF          */
220 } pdf_ctx;
221 
pdf_init(pdf_ctx * pc,aes_int_key prf_key)222 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
223 {
224     UINT8 buf[UMAC_KEY_LEN];
225 
226     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
227     aes_key_setup(buf, pc->prf_key);
228 
229     /* Initialize pdf and cache */
230     memset(pc->nonce, 0, sizeof(pc->nonce));
231     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
232     explicit_bzero(buf, sizeof(buf));
233 }
234 
pdf_gen_xor(pdf_ctx * pc,const UINT8 nonce[8],UINT8 buf[8])235 static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8])
236 {
237     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
238      * of the AES output. If last time around we returned the ndx-1st
239      * element, then we may have the result in the cache already.
240      */
241 
242 #if (UMAC_OUTPUT_LEN == 4)
243 #define LOW_BIT_MASK 3
244 #elif (UMAC_OUTPUT_LEN == 8)
245 #define LOW_BIT_MASK 1
246 #elif (UMAC_OUTPUT_LEN > 8)
247 #define LOW_BIT_MASK 0
248 #endif
249     union {
250         UINT8 tmp_nonce_lo[4];
251         UINT32 align;
252     } t;
253 #if LOW_BIT_MASK != 0
254     int ndx = nonce[7] & LOW_BIT_MASK;
255 #endif
256     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
257     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
258 
259     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
260          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
261     {
262         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
263         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
264         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
265     }
266 
267 #if (UMAC_OUTPUT_LEN == 4)
268     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
269 #elif (UMAC_OUTPUT_LEN == 8)
270     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
271 #elif (UMAC_OUTPUT_LEN == 12)
272     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
273     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
274 #elif (UMAC_OUTPUT_LEN == 16)
275     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
276     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
277 #endif
278 }
279 
280 /* ---------------------------------------------------------------------- */
281 /* ---------------------------------------------------------------------- */
282 /* ----- Begin NH Hash Section ------------------------------------------ */
283 /* ---------------------------------------------------------------------- */
284 /* ---------------------------------------------------------------------- */
285 
286 /* The NH-based hash functions used in UMAC are described in the UMAC paper
287  * and specification, both of which can be found at the UMAC website.
288  * The interface to this implementation has two
289  * versions, one expects the entire message being hashed to be passed
290  * in a single buffer and returns the hash result immediately. The second
291  * allows the message to be passed in a sequence of buffers. In the
292  * muliple-buffer interface, the client calls the routine nh_update() as
293  * many times as necessary. When there is no more data to be fed to the
294  * hash, the client calls nh_final() which calculates the hash output.
295  * Before beginning another hash calculation the nh_reset() routine
296  * must be called. The single-buffer routine, nh(), is equivalent to
297  * the sequence of calls nh_update() and nh_final(); however it is
298  * optimized and should be preferred whenever the multiple-buffer interface
299  * is not necessary. When using either interface, it is the client's
300  * responsibility to pass no more than L1_KEY_LEN bytes per hash result.
301  *
302  * The routine nh_init() initializes the nh_ctx data structure and
303  * must be called once, before any other PDF routine.
304  */
305 
306  /* The "nh_aux" routines do the actual NH hashing work. They
307   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
308   * produce output for all STREAMS NH iterations in one call,
309   * allowing the parallel implementation of the streams.
310   */
311 
312 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
313 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
314 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
315 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
316 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
317 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
318 
319 typedef struct {
320     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
321     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
322     int next_data_empty;    /* Bookkeeping variable for data buffer.     */
323     int bytes_hashed;       /* Bytes (out of L1_KEY_LEN) incorporated.   */
324     UINT64 state[STREAMS];               /* on-line state     */
325 } nh_ctx;
326 
327 
328 #if (UMAC_OUTPUT_LEN == 4)
329 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)330 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
331 /* NH hashing primitive. Previous (partial) hash result is loaded and
332 * then stored via hp pointer. The length of the data pointed at by "dp",
333 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
334 * is expected to be endian compensated in memory at key setup.
335 */
336 {
337     UINT64 h;
338     UWORD c = dlen / 32;
339     UINT32 *k = (UINT32 *)kp;
340     const UINT32 *d = (const UINT32 *)dp;
341     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
342     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
343 
344     h = *((UINT64 *)hp);
345     do {
346         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
347         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
348         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
349         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
350         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
351         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
352         h += MUL64((k0 + d0), (k4 + d4));
353         h += MUL64((k1 + d1), (k5 + d5));
354         h += MUL64((k2 + d2), (k6 + d6));
355         h += MUL64((k3 + d3), (k7 + d7));
356 
357         d += 8;
358         k += 8;
359     } while (--c);
360   *((UINT64 *)hp) = h;
361 }
362 
363 #elif (UMAC_OUTPUT_LEN == 8)
364 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)365 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
366 /* Same as previous nh_aux, but two streams are handled in one pass,
367  * reading and writing 16 bytes of hash-state per call.
368  */
369 {
370   UINT64 h1,h2;
371   UWORD c = dlen / 32;
372   UINT32 *k = (UINT32 *)kp;
373   const UINT32 *d = (const UINT32 *)dp;
374   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
375   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
376         k8,k9,k10,k11;
377 
378   h1 = *((UINT64 *)hp);
379   h2 = *((UINT64 *)hp + 1);
380   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
381   do {
382     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
383     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
384     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
385     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
386     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
387     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
388 
389     h1 += MUL64((k0 + d0), (k4 + d4));
390     h2 += MUL64((k4 + d0), (k8 + d4));
391 
392     h1 += MUL64((k1 + d1), (k5 + d5));
393     h2 += MUL64((k5 + d1), (k9 + d5));
394 
395     h1 += MUL64((k2 + d2), (k6 + d6));
396     h2 += MUL64((k6 + d2), (k10 + d6));
397 
398     h1 += MUL64((k3 + d3), (k7 + d7));
399     h2 += MUL64((k7 + d3), (k11 + d7));
400 
401     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
402 
403     d += 8;
404     k += 8;
405   } while (--c);
406   ((UINT64 *)hp)[0] = h1;
407   ((UINT64 *)hp)[1] = h2;
408 }
409 
410 #elif (UMAC_OUTPUT_LEN == 12)
411 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)412 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
413 /* Same as previous nh_aux, but two streams are handled in one pass,
414  * reading and writing 24 bytes of hash-state per call.
415 */
416 {
417     UINT64 h1,h2,h3;
418     UWORD c = dlen / 32;
419     UINT32 *k = (UINT32 *)kp;
420     const UINT32 *d = (const UINT32 *)dp;
421     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
422     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
423         k8,k9,k10,k11,k12,k13,k14,k15;
424 
425     h1 = *((UINT64 *)hp);
426     h2 = *((UINT64 *)hp + 1);
427     h3 = *((UINT64 *)hp + 2);
428     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
429     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
430     do {
431         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
432         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
433         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
434         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
435         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
436         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
437 
438         h1 += MUL64((k0 + d0), (k4 + d4));
439         h2 += MUL64((k4 + d0), (k8 + d4));
440         h3 += MUL64((k8 + d0), (k12 + d4));
441 
442         h1 += MUL64((k1 + d1), (k5 + d5));
443         h2 += MUL64((k5 + d1), (k9 + d5));
444         h3 += MUL64((k9 + d1), (k13 + d5));
445 
446         h1 += MUL64((k2 + d2), (k6 + d6));
447         h2 += MUL64((k6 + d2), (k10 + d6));
448         h3 += MUL64((k10 + d2), (k14 + d6));
449 
450         h1 += MUL64((k3 + d3), (k7 + d7));
451         h2 += MUL64((k7 + d3), (k11 + d7));
452         h3 += MUL64((k11 + d3), (k15 + d7));
453 
454         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
455         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
456 
457         d += 8;
458         k += 8;
459     } while (--c);
460     ((UINT64 *)hp)[0] = h1;
461     ((UINT64 *)hp)[1] = h2;
462     ((UINT64 *)hp)[2] = h3;
463 }
464 
465 #elif (UMAC_OUTPUT_LEN == 16)
466 
nh_aux(void * kp,const void * dp,void * hp,UINT32 dlen)467 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
468 /* Same as previous nh_aux, but two streams are handled in one pass,
469  * reading and writing 24 bytes of hash-state per call.
470 */
471 {
472     UINT64 h1,h2,h3,h4;
473     UWORD c = dlen / 32;
474     UINT32 *k = (UINT32 *)kp;
475     const UINT32 *d = (const UINT32 *)dp;
476     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
477     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
478         k8,k9,k10,k11,k12,k13,k14,k15,
479         k16,k17,k18,k19;
480 
481     h1 = *((UINT64 *)hp);
482     h2 = *((UINT64 *)hp + 1);
483     h3 = *((UINT64 *)hp + 2);
484     h4 = *((UINT64 *)hp + 3);
485     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
486     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
487     do {
488         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
489         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
490         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
491         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
492         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
493         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
494         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
495 
496         h1 += MUL64((k0 + d0), (k4 + d4));
497         h2 += MUL64((k4 + d0), (k8 + d4));
498         h3 += MUL64((k8 + d0), (k12 + d4));
499         h4 += MUL64((k12 + d0), (k16 + d4));
500 
501         h1 += MUL64((k1 + d1), (k5 + d5));
502         h2 += MUL64((k5 + d1), (k9 + d5));
503         h3 += MUL64((k9 + d1), (k13 + d5));
504         h4 += MUL64((k13 + d1), (k17 + d5));
505 
506         h1 += MUL64((k2 + d2), (k6 + d6));
507         h2 += MUL64((k6 + d2), (k10 + d6));
508         h3 += MUL64((k10 + d2), (k14 + d6));
509         h4 += MUL64((k14 + d2), (k18 + d6));
510 
511         h1 += MUL64((k3 + d3), (k7 + d7));
512         h2 += MUL64((k7 + d3), (k11 + d7));
513         h3 += MUL64((k11 + d3), (k15 + d7));
514         h4 += MUL64((k15 + d3), (k19 + d7));
515 
516         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
517         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
518         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
519 
520         d += 8;
521         k += 8;
522     } while (--c);
523     ((UINT64 *)hp)[0] = h1;
524     ((UINT64 *)hp)[1] = h2;
525     ((UINT64 *)hp)[2] = h3;
526     ((UINT64 *)hp)[3] = h4;
527 }
528 
529 /* ---------------------------------------------------------------------- */
530 #endif  /* UMAC_OUTPUT_LENGTH */
531 /* ---------------------------------------------------------------------- */
532 
533 
534 /* ---------------------------------------------------------------------- */
535 
nh_transform(nh_ctx * hc,const UINT8 * buf,UINT32 nbytes)536 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
537 /* This function is a wrapper for the primitive NH hash functions. It takes
538  * as argument "hc" the current hash context and a buffer which must be a
539  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
540  * appropriately according to how much message has been hashed already.
541  */
542 {
543     UINT8 *key;
544 
545     key = hc->nh_key + hc->bytes_hashed;
546     nh_aux(key, buf, hc->state, nbytes);
547 }
548 
549 /* ---------------------------------------------------------------------- */
550 
551 #if (__LITTLE_ENDIAN__)
endian_convert(void * buf,UWORD bpw,UINT32 num_bytes)552 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
553 /* We endian convert the keys on little-endian computers to               */
554 /* compensate for the lack of big-endian memory reads during hashing.     */
555 {
556     UWORD iters = num_bytes / bpw;
557     if (bpw == 4) {
558         UINT32 *p = (UINT32 *)buf;
559         do {
560             *p = LOAD_UINT32_REVERSED(p);
561             p++;
562         } while (--iters);
563     } else if (bpw == 8) {
564         UINT32 *p = (UINT32 *)buf;
565         UINT32 t;
566         do {
567             t = LOAD_UINT32_REVERSED(p+1);
568             p[1] = LOAD_UINT32_REVERSED(p);
569             p[0] = t;
570             p += 2;
571         } while (--iters);
572     }
573 }
574 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
575 #else
576 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
577 #endif
578 
579 /* ---------------------------------------------------------------------- */
580 
nh_reset(nh_ctx * hc)581 static void nh_reset(nh_ctx *hc)
582 /* Reset nh_ctx to ready for hashing of new data */
583 {
584     hc->bytes_hashed = 0;
585     hc->next_data_empty = 0;
586     hc->state[0] = 0;
587 #if (UMAC_OUTPUT_LEN >= 8)
588     hc->state[1] = 0;
589 #endif
590 #if (UMAC_OUTPUT_LEN >= 12)
591     hc->state[2] = 0;
592 #endif
593 #if (UMAC_OUTPUT_LEN == 16)
594     hc->state[3] = 0;
595 #endif
596 
597 }
598 
599 /* ---------------------------------------------------------------------- */
600 
nh_init(nh_ctx * hc,aes_int_key prf_key)601 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
602 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
603 {
604     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
605     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
606     nh_reset(hc);
607 }
608 
609 /* ---------------------------------------------------------------------- */
610 
nh_update(nh_ctx * hc,const UINT8 * buf,UINT32 nbytes)611 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
612 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
613 /* even multiple of HASH_BUF_BYTES.                                       */
614 {
615     UINT32 i,j;
616 
617     j = hc->next_data_empty;
618     if ((j + nbytes) >= HASH_BUF_BYTES) {
619         if (j) {
620             i = HASH_BUF_BYTES - j;
621             memcpy(hc->data+j, buf, i);
622             nh_transform(hc,hc->data,HASH_BUF_BYTES);
623             nbytes -= i;
624             buf += i;
625             hc->bytes_hashed += HASH_BUF_BYTES;
626         }
627         if (nbytes >= HASH_BUF_BYTES) {
628             i = nbytes & ~(HASH_BUF_BYTES - 1);
629             nh_transform(hc, buf, i);
630             nbytes -= i;
631             buf += i;
632             hc->bytes_hashed += i;
633         }
634         j = 0;
635     }
636     memcpy(hc->data + j, buf, nbytes);
637     hc->next_data_empty = j + nbytes;
638 }
639 
640 /* ---------------------------------------------------------------------- */
641 
zero_pad(UINT8 * p,int nbytes)642 static void zero_pad(UINT8 *p, int nbytes)
643 {
644 /* Write "nbytes" of zeroes, beginning at "p" */
645     if (nbytes >= (int)sizeof(UWORD)) {
646         while ((ptrdiff_t)p % sizeof(UWORD)) {
647             *p = 0;
648             nbytes--;
649             p++;
650         }
651         while (nbytes >= (int)sizeof(UWORD)) {
652             *(UWORD *)p = 0;
653             nbytes -= sizeof(UWORD);
654             p += sizeof(UWORD);
655         }
656     }
657     while (nbytes) {
658         *p = 0;
659         nbytes--;
660         p++;
661     }
662 }
663 
664 /* ---------------------------------------------------------------------- */
665 
nh_final(nh_ctx * hc,UINT8 * result)666 static void nh_final(nh_ctx *hc, UINT8 *result)
667 /* After passing some number of data buffers to nh_update() for integration
668  * into an NH context, nh_final is called to produce a hash result. If any
669  * bytes are in the buffer hc->data, incorporate them into the
670  * NH context. Finally, add into the NH accumulation "state" the total number
671  * of bits hashed. The resulting numbers are written to the buffer "result".
672  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
673  */
674 {
675     int nh_len, nbits;
676 
677     if (hc->next_data_empty != 0) {
678         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
679                                                 ~(L1_PAD_BOUNDARY - 1));
680         zero_pad(hc->data + hc->next_data_empty,
681                                           nh_len - hc->next_data_empty);
682         nh_transform(hc, hc->data, nh_len);
683         hc->bytes_hashed += hc->next_data_empty;
684     } else if (hc->bytes_hashed == 0) {
685 	nh_len = L1_PAD_BOUNDARY;
686         zero_pad(hc->data, L1_PAD_BOUNDARY);
687         nh_transform(hc, hc->data, nh_len);
688     }
689 
690     nbits = (hc->bytes_hashed << 3);
691     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
692 #if (UMAC_OUTPUT_LEN >= 8)
693     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
694 #endif
695 #if (UMAC_OUTPUT_LEN >= 12)
696     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
697 #endif
698 #if (UMAC_OUTPUT_LEN == 16)
699     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
700 #endif
701     nh_reset(hc);
702 }
703 
704 /* ---------------------------------------------------------------------- */
705 
nh(nh_ctx * hc,const UINT8 * buf,UINT32 padded_len,UINT32 unpadded_len,UINT8 * result)706 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
707                UINT32 unpadded_len, UINT8 *result)
708 /* All-in-one nh_update() and nh_final() equivalent.
709  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
710  * well aligned
711  */
712 {
713     UINT32 nbits;
714 
715     /* Initialize the hash state */
716     nbits = (unpadded_len << 3);
717 
718     ((UINT64 *)result)[0] = nbits;
719 #if (UMAC_OUTPUT_LEN >= 8)
720     ((UINT64 *)result)[1] = nbits;
721 #endif
722 #if (UMAC_OUTPUT_LEN >= 12)
723     ((UINT64 *)result)[2] = nbits;
724 #endif
725 #if (UMAC_OUTPUT_LEN == 16)
726     ((UINT64 *)result)[3] = nbits;
727 #endif
728 
729     nh_aux(hc->nh_key, buf, result, padded_len);
730 }
731 
732 /* ---------------------------------------------------------------------- */
733 /* ---------------------------------------------------------------------- */
734 /* ----- Begin UHASH Section -------------------------------------------- */
735 /* ---------------------------------------------------------------------- */
736 /* ---------------------------------------------------------------------- */
737 
738 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
739  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
740  * unless the initial data to be hashed is short. After the polynomial-
741  * layer, an inner-product hash is used to produce the final UHASH output.
742  *
743  * UHASH provides two interfaces, one all-at-once and another where data
744  * buffers are presented sequentially. In the sequential interface, the
745  * UHASH client calls the routine uhash_update() as many times as necessary.
746  * When there is no more data to be fed to UHASH, the client calls
747  * uhash_final() which
748  * calculates the UHASH output. Before beginning another UHASH calculation
749  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
750  * uhash(), is equivalent to the sequence of calls uhash_update() and
751  * uhash_final(); however it is optimized and should be
752  * used whenever the sequential interface is not necessary.
753  *
754  * The routine uhash_init() initializes the uhash_ctx data structure and
755  * must be called once, before any other UHASH routine.
756  */
757 
758 /* ---------------------------------------------------------------------- */
759 /* ----- Constants and uhash_ctx ---------------------------------------- */
760 /* ---------------------------------------------------------------------- */
761 
762 /* ---------------------------------------------------------------------- */
763 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
764 /* ---------------------------------------------------------------------- */
765 
766 /* Primes and masks */
767 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
768 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
769 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
770 
771 
772 /* ---------------------------------------------------------------------- */
773 
774 typedef struct uhash_ctx {
775     nh_ctx hash;                          /* Hash context for L1 NH hash  */
776     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
777     UINT64 poly_accum[STREAMS];           /* poly hash result             */
778     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
779     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
780     UINT32 msg_len;                       /* Total length of data passed  */
781                                           /* to uhash */
782 } uhash_ctx;
783 typedef struct uhash_ctx *uhash_ctx_t;
784 
785 /* ---------------------------------------------------------------------- */
786 
787 
788 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
789  * word at a time. As described in the specification, poly32 and poly64
790  * require keys from special domains. The following implementations exploit
791  * the special domains to avoid overflow. The results are not guaranteed to
792  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
793  * patches any errant values.
794  */
795 
poly64(UINT64 cur,UINT64 key,UINT64 data)796 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
797 {
798     UINT32 key_hi = (UINT32)(key >> 32),
799            key_lo = (UINT32)key,
800            cur_hi = (UINT32)(cur >> 32),
801            cur_lo = (UINT32)cur,
802            x_lo,
803            x_hi;
804     UINT64 X,T,res;
805 
806     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
807     x_lo = (UINT32)X;
808     x_hi = (UINT32)(X >> 32);
809 
810     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
811 
812     T = ((UINT64)x_lo << 32);
813     res += T;
814     if (res < T)
815         res += 59;
816 
817     res += data;
818     if (res < data)
819         res += 59;
820 
821     return res;
822 }
823 
824 
825 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
826  * implementation does not handle all ramp levels. Because we don't handle
827  * the ramp up to p128 modulus in this implementation, we are limited to
828  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
829  * bytes input to UMAC per tag, ie. 16MB).
830  */
poly_hash(uhash_ctx_t hc,UINT32 data_in[])831 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
832 {
833     int i;
834     UINT64 *data=(UINT64*)data_in;
835 
836     for (i = 0; i < STREAMS; i++) {
837         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
838             hc->poly_accum[i] = poly64(hc->poly_accum[i],
839                                        hc->poly_key_8[i], p64 - 1);
840             hc->poly_accum[i] = poly64(hc->poly_accum[i],
841                                        hc->poly_key_8[i], (data[i] - 59));
842         } else {
843             hc->poly_accum[i] = poly64(hc->poly_accum[i],
844                                        hc->poly_key_8[i], data[i]);
845         }
846     }
847 }
848 
849 
850 /* ---------------------------------------------------------------------- */
851 
852 
853 /* The final step in UHASH is an inner-product hash. The poly hash
854  * produces a result not necessarily WORD_LEN bytes long. The inner-
855  * product hash breaks the polyhash output into 16-bit chunks and
856  * multiplies each with a 36 bit key.
857  */
858 
ip_aux(UINT64 t,UINT64 * ipkp,UINT64 data)859 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
860 {
861     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
862     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
863     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
864     t = t + ipkp[3] * (UINT64)(UINT16)(data);
865 
866     return t;
867 }
868 
ip_reduce_p36(UINT64 t)869 static UINT32 ip_reduce_p36(UINT64 t)
870 {
871 /* Divisionless modular reduction */
872     UINT64 ret;
873 
874     ret = (t & m36) + 5 * (t >> 36);
875     if (ret >= p36)
876         ret -= p36;
877 
878     /* return least significant 32 bits */
879     return (UINT32)(ret);
880 }
881 
882 
883 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
884  * the polyhash stage is skipped and ip_short is applied directly to the
885  * NH output.
886  */
ip_short(uhash_ctx_t ahc,UINT8 * nh_res,u_char * res)887 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
888 {
889     UINT64 t;
890     UINT64 *nhp = (UINT64 *)nh_res;
891 
892     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
893     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
894 #if (UMAC_OUTPUT_LEN >= 8)
895     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
896     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
897 #endif
898 #if (UMAC_OUTPUT_LEN >= 12)
899     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
900     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
901 #endif
902 #if (UMAC_OUTPUT_LEN == 16)
903     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
904     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
905 #endif
906 }
907 
908 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
909  * the polyhash stage is not skipped and ip_long is applied to the
910  * polyhash output.
911  */
ip_long(uhash_ctx_t ahc,u_char * res)912 static void ip_long(uhash_ctx_t ahc, u_char *res)
913 {
914     int i;
915     UINT64 t;
916 
917     for (i = 0; i < STREAMS; i++) {
918         /* fix polyhash output not in Z_p64 */
919         if (ahc->poly_accum[i] >= p64)
920             ahc->poly_accum[i] -= p64;
921         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
922         STORE_UINT32_BIG((UINT32 *)res+i,
923                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
924     }
925 }
926 
927 
928 /* ---------------------------------------------------------------------- */
929 
930 /* ---------------------------------------------------------------------- */
931 
932 /* Reset uhash context for next hash session */
uhash_reset(uhash_ctx_t pc)933 static int uhash_reset(uhash_ctx_t pc)
934 {
935     nh_reset(&pc->hash);
936     pc->msg_len = 0;
937     pc->poly_accum[0] = 1;
938 #if (UMAC_OUTPUT_LEN >= 8)
939     pc->poly_accum[1] = 1;
940 #endif
941 #if (UMAC_OUTPUT_LEN >= 12)
942     pc->poly_accum[2] = 1;
943 #endif
944 #if (UMAC_OUTPUT_LEN == 16)
945     pc->poly_accum[3] = 1;
946 #endif
947     return 1;
948 }
949 
950 /* ---------------------------------------------------------------------- */
951 
952 /* Given a pointer to the internal key needed by kdf() and a uhash context,
953  * initialize the NH context and generate keys needed for poly and inner-
954  * product hashing. All keys are endian adjusted in memory so that native
955  * loads cause correct keys to be in registers during calculation.
956  */
uhash_init(uhash_ctx_t ahc,aes_int_key prf_key)957 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
958 {
959     int i;
960     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
961 
962     /* Zero the entire uhash context */
963     memset(ahc, 0, sizeof(uhash_ctx));
964 
965     /* Initialize the L1 hash */
966     nh_init(&ahc->hash, prf_key);
967 
968     /* Setup L2 hash variables */
969     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
970     for (i = 0; i < STREAMS; i++) {
971         /* Fill keys from the buffer, skipping bytes in the buffer not
972          * used by this implementation. Endian reverse the keys if on a
973          * little-endian computer.
974          */
975         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
976         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
977         /* Mask the 64-bit keys to their special domain */
978         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
979         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
980     }
981 
982     /* Setup L3-1 hash variables */
983     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
984     for (i = 0; i < STREAMS; i++)
985           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
986                                                  4*sizeof(UINT64));
987     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
988                                                   sizeof(ahc->ip_keys));
989     for (i = 0; i < STREAMS*4; i++)
990         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
991 
992     /* Setup L3-2 hash variables    */
993     /* Fill buffer with index 4 key */
994     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
995     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
996                          STREAMS * sizeof(UINT32));
997     explicit_bzero(buf, sizeof(buf));
998 }
999 
1000 /* ---------------------------------------------------------------------- */
1001 
1002 #if 0
1003 static uhash_ctx_t uhash_alloc(u_char key[])
1004 {
1005 /* Allocate memory and force to a 16-byte boundary. */
1006     uhash_ctx_t ctx;
1007     u_char bytes_to_add;
1008     aes_int_key prf_key;
1009 
1010     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1011     if (ctx) {
1012         if (ALLOC_BOUNDARY) {
1013             bytes_to_add = ALLOC_BOUNDARY -
1014                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1015             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1016             *((u_char *)ctx - 1) = bytes_to_add;
1017         }
1018         aes_key_setup(key,prf_key);
1019         uhash_init(ctx, prf_key);
1020     }
1021     return (ctx);
1022 }
1023 #endif
1024 
1025 /* ---------------------------------------------------------------------- */
1026 
1027 #if 0
1028 static int uhash_free(uhash_ctx_t ctx)
1029 {
1030 /* Free memory allocated by uhash_alloc */
1031     u_char bytes_to_sub;
1032 
1033     if (ctx) {
1034         if (ALLOC_BOUNDARY) {
1035             bytes_to_sub = *((u_char *)ctx - 1);
1036             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1037         }
1038         free(ctx);
1039     }
1040     return (1);
1041 }
1042 #endif
1043 /* ---------------------------------------------------------------------- */
1044 
uhash_update(uhash_ctx_t ctx,const u_char * input,long len)1045 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1046 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1047  * hash each one with NH, calling the polyhash on each NH output.
1048  */
1049 {
1050     UWORD bytes_hashed, bytes_remaining;
1051     UINT64 result_buf[STREAMS];
1052     UINT8 *nh_result = (UINT8 *)&result_buf;
1053 
1054     if (ctx->msg_len + len <= L1_KEY_LEN) {
1055         nh_update(&ctx->hash, (const UINT8 *)input, len);
1056         ctx->msg_len += len;
1057     } else {
1058 
1059          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1060          if (ctx->msg_len == L1_KEY_LEN)
1061              bytes_hashed = L1_KEY_LEN;
1062 
1063          if (bytes_hashed + len >= L1_KEY_LEN) {
1064 
1065              /* If some bytes have been passed to the hash function      */
1066              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1067              /* bytes to complete the current nh_block.                  */
1068              if (bytes_hashed) {
1069                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1070                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1071                  nh_final(&ctx->hash, nh_result);
1072                  ctx->msg_len += bytes_remaining;
1073                  poly_hash(ctx,(UINT32 *)nh_result);
1074                  len -= bytes_remaining;
1075                  input += bytes_remaining;
1076              }
1077 
1078              /* Hash directly from input stream if enough bytes */
1079              while (len >= L1_KEY_LEN) {
1080                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1081                                    L1_KEY_LEN, nh_result);
1082                  ctx->msg_len += L1_KEY_LEN;
1083                  len -= L1_KEY_LEN;
1084                  input += L1_KEY_LEN;
1085                  poly_hash(ctx,(UINT32 *)nh_result);
1086              }
1087          }
1088 
1089          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1090          if (len) {
1091              nh_update(&ctx->hash, (const UINT8 *)input, len);
1092              ctx->msg_len += len;
1093          }
1094      }
1095 
1096     return (1);
1097 }
1098 
1099 /* ---------------------------------------------------------------------- */
1100 
uhash_final(uhash_ctx_t ctx,u_char * res)1101 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1102 /* Incorporate any pending data, pad, and generate tag */
1103 {
1104     UINT64 result_buf[STREAMS];
1105     UINT8 *nh_result = (UINT8 *)&result_buf;
1106 
1107     if (ctx->msg_len > L1_KEY_LEN) {
1108         if (ctx->msg_len % L1_KEY_LEN) {
1109             nh_final(&ctx->hash, nh_result);
1110             poly_hash(ctx,(UINT32 *)nh_result);
1111         }
1112         ip_long(ctx, res);
1113     } else {
1114         nh_final(&ctx->hash, nh_result);
1115         ip_short(ctx,nh_result, res);
1116     }
1117     uhash_reset(ctx);
1118     return (1);
1119 }
1120 
1121 /* ---------------------------------------------------------------------- */
1122 
1123 #if 0
1124 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1125 /* assumes that msg is in a writable buffer of length divisible by */
1126 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1127 {
1128     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1129     UINT32 nh_len;
1130     int extra_zeroes_needed;
1131 
1132     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1133      * the polyhash.
1134      */
1135     if (len <= L1_KEY_LEN) {
1136 	if (len == 0)                  /* If zero length messages will not */
1137 		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1138 	else
1139 		nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1140         extra_zeroes_needed = nh_len - len;
1141         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1142         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1143         ip_short(ahc,nh_result, res);
1144     } else {
1145         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1146          * output to poly_hash().
1147          */
1148         do {
1149             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1150             poly_hash(ahc,(UINT32 *)nh_result);
1151             len -= L1_KEY_LEN;
1152             msg += L1_KEY_LEN;
1153         } while (len >= L1_KEY_LEN);
1154         if (len) {
1155             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1156             extra_zeroes_needed = nh_len - len;
1157             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1158             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1159             poly_hash(ahc,(UINT32 *)nh_result);
1160         }
1161 
1162         ip_long(ahc, res);
1163     }
1164 
1165     uhash_reset(ahc);
1166     return 1;
1167 }
1168 #endif
1169 
1170 /* ---------------------------------------------------------------------- */
1171 /* ---------------------------------------------------------------------- */
1172 /* ----- Begin UMAC Section --------------------------------------------- */
1173 /* ---------------------------------------------------------------------- */
1174 /* ---------------------------------------------------------------------- */
1175 
1176 /* The UMAC interface has two interfaces, an all-at-once interface where
1177  * the entire message to be authenticated is passed to UMAC in one buffer,
1178  * and a sequential interface where the message is presented a little at a
1179  * time. The all-at-once is more optimaized than the sequential version and
1180  * should be preferred when the sequential interface is not required.
1181  */
1182 struct umac_ctx {
1183     uhash_ctx hash;          /* Hash function for message compression    */
1184     pdf_ctx pdf;             /* PDF for hashed output                    */
1185     void *free_ptr;          /* Address to free this struct via          */
1186 } umac_ctx;
1187 
1188 /* ---------------------------------------------------------------------- */
1189 
1190 #if 0
1191 int umac_reset(struct umac_ctx *ctx)
1192 /* Reset the hash function to begin a new authentication.        */
1193 {
1194     uhash_reset(&ctx->hash);
1195     return (1);
1196 }
1197 #endif
1198 
1199 /* ---------------------------------------------------------------------- */
1200 
umac_delete(struct umac_ctx * ctx)1201 int umac_delete(struct umac_ctx *ctx)
1202 /* Deallocate the ctx structure */
1203 {
1204     if (ctx) {
1205         if (ALLOC_BOUNDARY)
1206             ctx = (struct umac_ctx *)ctx->free_ptr;
1207         explicit_bzero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY);
1208         free(ctx);
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