1/* $OpenBSD: umac.c,v 1.23 2023/03/07 01:30:52 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 */
91typedef u_int8_t	UINT8;  /* 1 byte   */
92typedef u_int16_t	UINT16; /* 2 byte   */
93typedef u_int32_t	UINT32; /* 4 byte   */
94typedef u_int64_t	UINT64; /* 8 bytes  */
95typedef 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
163typedef 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)
171typedef 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 */
185static 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
217typedef 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
223static 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
236static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8],
237    UINT8 buf[UMAC_OUTPUT_LEN])
238{
239    /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
240     * of the AES output. If last time around we returned the ndx-1st
241     * element, then we may have the result in the cache already.
242     */
243
244#if (UMAC_OUTPUT_LEN == 4)
245#define LOW_BIT_MASK 3
246#elif (UMAC_OUTPUT_LEN == 8)
247#define LOW_BIT_MASK 1
248#elif (UMAC_OUTPUT_LEN > 8)
249#define LOW_BIT_MASK 0
250#endif
251    union {
252        UINT8 tmp_nonce_lo[4];
253        UINT32 align;
254    } t;
255#if LOW_BIT_MASK != 0
256    int ndx = nonce[7] & LOW_BIT_MASK;
257#endif
258    *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
259    t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
260
261    if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
262         (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
263    {
264        ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
265        ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
266        aes_encryption(pc->nonce, pc->cache, pc->prf_key);
267    }
268
269#if (UMAC_OUTPUT_LEN == 4)
270    *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
271#elif (UMAC_OUTPUT_LEN == 8)
272    *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
273#elif (UMAC_OUTPUT_LEN == 12)
274    ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
275    ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
276#elif (UMAC_OUTPUT_LEN == 16)
277    ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
278    ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
279#endif
280}
281
282/* ---------------------------------------------------------------------- */
283/* ---------------------------------------------------------------------- */
284/* ----- Begin NH Hash Section ------------------------------------------ */
285/* ---------------------------------------------------------------------- */
286/* ---------------------------------------------------------------------- */
287
288/* The NH-based hash functions used in UMAC are described in the UMAC paper
289 * and specification, both of which can be found at the UMAC website.
290 * The interface to this implementation has two
291 * versions, one expects the entire message being hashed to be passed
292 * in a single buffer and returns the hash result immediately. The second
293 * allows the message to be passed in a sequence of buffers. In the
294 * multiple-buffer interface, the client calls the routine nh_update() as
295 * many times as necessary. When there is no more data to be fed to the
296 * hash, the client calls nh_final() which calculates the hash output.
297 * Before beginning another hash calculation the nh_reset() routine
298 * must be called. The single-buffer routine, nh(), is equivalent to
299 * the sequence of calls nh_update() and nh_final(); however it is
300 * optimized and should be preferred whenever the multiple-buffer interface
301 * is not necessary. When using either interface, it is the client's
302 * responsibility to pass no more than L1_KEY_LEN bytes per hash result.
303 *
304 * The routine nh_init() initializes the nh_ctx data structure and
305 * must be called once, before any other PDF routine.
306 */
307
308 /* The "nh_aux" routines do the actual NH hashing work. They
309  * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
310  * produce output for all STREAMS NH iterations in one call,
311  * allowing the parallel implementation of the streams.
312  */
313
314#define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
315#define L1_KEY_LEN         1024     /* Internal key bytes                 */
316#define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
317#define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
318#define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
319#define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
320
321typedef struct {
322    UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
323    UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
324    int next_data_empty;    /* Bookkeeping variable for data buffer.     */
325    int bytes_hashed;       /* Bytes (out of L1_KEY_LEN) incorporated.   */
326    UINT64 state[STREAMS];               /* on-line state     */
327} nh_ctx;
328
329
330#if (UMAC_OUTPUT_LEN == 4)
331
332static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
333/* NH hashing primitive. Previous (partial) hash result is loaded and
334* then stored via hp pointer. The length of the data pointed at by "dp",
335* "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
336* is expected to be endian compensated in memory at key setup.
337*/
338{
339    UINT64 h;
340    UWORD c = dlen / 32;
341    UINT32 *k = (UINT32 *)kp;
342    const UINT32 *d = (const UINT32 *)dp;
343    UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
344    UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
345
346    h = *((UINT64 *)hp);
347    do {
348        d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
349        d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
350        d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
351        d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
352        k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
353        k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
354        h += MUL64((k0 + d0), (k4 + d4));
355        h += MUL64((k1 + d1), (k5 + d5));
356        h += MUL64((k2 + d2), (k6 + d6));
357        h += MUL64((k3 + d3), (k7 + d7));
358
359        d += 8;
360        k += 8;
361    } while (--c);
362  *((UINT64 *)hp) = h;
363}
364
365#elif (UMAC_OUTPUT_LEN == 8)
366
367static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
368/* Same as previous nh_aux, but two streams are handled in one pass,
369 * reading and writing 16 bytes of hash-state per call.
370 */
371{
372  UINT64 h1,h2;
373  UWORD c = dlen / 32;
374  UINT32 *k = (UINT32 *)kp;
375  const UINT32 *d = (const UINT32 *)dp;
376  UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
377  UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
378        k8,k9,k10,k11;
379
380  h1 = *((UINT64 *)hp);
381  h2 = *((UINT64 *)hp + 1);
382  k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
383  do {
384    d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
385    d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
386    d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
387    d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
388    k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
389    k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
390
391    h1 += MUL64((k0 + d0), (k4 + d4));
392    h2 += MUL64((k4 + d0), (k8 + d4));
393
394    h1 += MUL64((k1 + d1), (k5 + d5));
395    h2 += MUL64((k5 + d1), (k9 + d5));
396
397    h1 += MUL64((k2 + d2), (k6 + d6));
398    h2 += MUL64((k6 + d2), (k10 + d6));
399
400    h1 += MUL64((k3 + d3), (k7 + d7));
401    h2 += MUL64((k7 + d3), (k11 + d7));
402
403    k0 = k8; k1 = k9; k2 = k10; k3 = k11;
404
405    d += 8;
406    k += 8;
407  } while (--c);
408  ((UINT64 *)hp)[0] = h1;
409  ((UINT64 *)hp)[1] = h2;
410}
411
412#elif (UMAC_OUTPUT_LEN == 12)
413
414static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
415/* Same as previous nh_aux, but two streams are handled in one pass,
416 * reading and writing 24 bytes of hash-state per call.
417*/
418{
419    UINT64 h1,h2,h3;
420    UWORD c = dlen / 32;
421    UINT32 *k = (UINT32 *)kp;
422    const UINT32 *d = (const UINT32 *)dp;
423    UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
424    UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
425        k8,k9,k10,k11,k12,k13,k14,k15;
426
427    h1 = *((UINT64 *)hp);
428    h2 = *((UINT64 *)hp + 1);
429    h3 = *((UINT64 *)hp + 2);
430    k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
431    k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
432    do {
433        d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
434        d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
435        d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
436        d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
437        k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
438        k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
439
440        h1 += MUL64((k0 + d0), (k4 + d4));
441        h2 += MUL64((k4 + d0), (k8 + d4));
442        h3 += MUL64((k8 + d0), (k12 + d4));
443
444        h1 += MUL64((k1 + d1), (k5 + d5));
445        h2 += MUL64((k5 + d1), (k9 + d5));
446        h3 += MUL64((k9 + d1), (k13 + d5));
447
448        h1 += MUL64((k2 + d2), (k6 + d6));
449        h2 += MUL64((k6 + d2), (k10 + d6));
450        h3 += MUL64((k10 + d2), (k14 + d6));
451
452        h1 += MUL64((k3 + d3), (k7 + d7));
453        h2 += MUL64((k7 + d3), (k11 + d7));
454        h3 += MUL64((k11 + d3), (k15 + d7));
455
456        k0 = k8; k1 = k9; k2 = k10; k3 = k11;
457        k4 = k12; k5 = k13; k6 = k14; k7 = k15;
458
459        d += 8;
460        k += 8;
461    } while (--c);
462    ((UINT64 *)hp)[0] = h1;
463    ((UINT64 *)hp)[1] = h2;
464    ((UINT64 *)hp)[2] = h3;
465}
466
467#elif (UMAC_OUTPUT_LEN == 16)
468
469static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
470/* Same as previous nh_aux, but two streams are handled in one pass,
471 * reading and writing 24 bytes of hash-state per call.
472*/
473{
474    UINT64 h1,h2,h3,h4;
475    UWORD c = dlen / 32;
476    UINT32 *k = (UINT32 *)kp;
477    const UINT32 *d = (const UINT32 *)dp;
478    UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
479    UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
480        k8,k9,k10,k11,k12,k13,k14,k15,
481        k16,k17,k18,k19;
482
483    h1 = *((UINT64 *)hp);
484    h2 = *((UINT64 *)hp + 1);
485    h3 = *((UINT64 *)hp + 2);
486    h4 = *((UINT64 *)hp + 3);
487    k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
488    k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
489    do {
490        d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
491        d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
492        d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
493        d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
494        k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
495        k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
496        k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
497
498        h1 += MUL64((k0 + d0), (k4 + d4));
499        h2 += MUL64((k4 + d0), (k8 + d4));
500        h3 += MUL64((k8 + d0), (k12 + d4));
501        h4 += MUL64((k12 + d0), (k16 + d4));
502
503        h1 += MUL64((k1 + d1), (k5 + d5));
504        h2 += MUL64((k5 + d1), (k9 + d5));
505        h3 += MUL64((k9 + d1), (k13 + d5));
506        h4 += MUL64((k13 + d1), (k17 + d5));
507
508        h1 += MUL64((k2 + d2), (k6 + d6));
509        h2 += MUL64((k6 + d2), (k10 + d6));
510        h3 += MUL64((k10 + d2), (k14 + d6));
511        h4 += MUL64((k14 + d2), (k18 + d6));
512
513        h1 += MUL64((k3 + d3), (k7 + d7));
514        h2 += MUL64((k7 + d3), (k11 + d7));
515        h3 += MUL64((k11 + d3), (k15 + d7));
516        h4 += MUL64((k15 + d3), (k19 + d7));
517
518        k0 = k8; k1 = k9; k2 = k10; k3 = k11;
519        k4 = k12; k5 = k13; k6 = k14; k7 = k15;
520        k8 = k16; k9 = k17; k10 = k18; k11 = k19;
521
522        d += 8;
523        k += 8;
524    } while (--c);
525    ((UINT64 *)hp)[0] = h1;
526    ((UINT64 *)hp)[1] = h2;
527    ((UINT64 *)hp)[2] = h3;
528    ((UINT64 *)hp)[3] = h4;
529}
530
531/* ---------------------------------------------------------------------- */
532#endif  /* UMAC_OUTPUT_LENGTH */
533/* ---------------------------------------------------------------------- */
534
535
536/* ---------------------------------------------------------------------- */
537
538static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
539/* This function is a wrapper for the primitive NH hash functions. It takes
540 * as argument "hc" the current hash context and a buffer which must be a
541 * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
542 * appropriately according to how much message has been hashed already.
543 */
544{
545    UINT8 *key;
546
547    key = hc->nh_key + hc->bytes_hashed;
548    nh_aux(key, buf, hc->state, nbytes);
549}
550
551/* ---------------------------------------------------------------------- */
552
553#if (__LITTLE_ENDIAN__)
554static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
555/* We endian convert the keys on little-endian computers to               */
556/* compensate for the lack of big-endian memory reads during hashing.     */
557{
558    UWORD iters = num_bytes / bpw;
559    if (bpw == 4) {
560        UINT32 *p = (UINT32 *)buf;
561        do {
562            *p = LOAD_UINT32_REVERSED(p);
563            p++;
564        } while (--iters);
565    } else if (bpw == 8) {
566        UINT32 *p = (UINT32 *)buf;
567        UINT32 t;
568        do {
569            t = LOAD_UINT32_REVERSED(p+1);
570            p[1] = LOAD_UINT32_REVERSED(p);
571            p[0] = t;
572            p += 2;
573        } while (--iters);
574    }
575}
576#define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
577#else
578#define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
579#endif
580
581/* ---------------------------------------------------------------------- */
582
583static void nh_reset(nh_ctx *hc)
584/* Reset nh_ctx to ready for hashing of new data */
585{
586    hc->bytes_hashed = 0;
587    hc->next_data_empty = 0;
588    hc->state[0] = 0;
589#if (UMAC_OUTPUT_LEN >= 8)
590    hc->state[1] = 0;
591#endif
592#if (UMAC_OUTPUT_LEN >= 12)
593    hc->state[2] = 0;
594#endif
595#if (UMAC_OUTPUT_LEN == 16)
596    hc->state[3] = 0;
597#endif
598
599}
600
601/* ---------------------------------------------------------------------- */
602
603static void nh_init(nh_ctx *hc, aes_int_key prf_key)
604/* Generate nh_key, endian convert and reset to be ready for hashing.   */
605{
606    kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
607    endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
608    nh_reset(hc);
609}
610
611/* ---------------------------------------------------------------------- */
612
613static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
614/* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
615/* even multiple of HASH_BUF_BYTES.                                       */
616{
617    UINT32 i,j;
618
619    j = hc->next_data_empty;
620    if ((j + nbytes) >= HASH_BUF_BYTES) {
621        if (j) {
622            i = HASH_BUF_BYTES - j;
623            memcpy(hc->data+j, buf, i);
624            nh_transform(hc,hc->data,HASH_BUF_BYTES);
625            nbytes -= i;
626            buf += i;
627            hc->bytes_hashed += HASH_BUF_BYTES;
628        }
629        if (nbytes >= HASH_BUF_BYTES) {
630            i = nbytes & ~(HASH_BUF_BYTES - 1);
631            nh_transform(hc, buf, i);
632            nbytes -= i;
633            buf += i;
634            hc->bytes_hashed += i;
635        }
636        j = 0;
637    }
638    memcpy(hc->data + j, buf, nbytes);
639    hc->next_data_empty = j + nbytes;
640}
641
642/* ---------------------------------------------------------------------- */
643
644static void zero_pad(UINT8 *p, int nbytes)
645{
646/* Write "nbytes" of zeroes, beginning at "p" */
647    if (nbytes >= (int)sizeof(UWORD)) {
648        while ((ptrdiff_t)p % sizeof(UWORD)) {
649            *p = 0;
650            nbytes--;
651            p++;
652        }
653        while (nbytes >= (int)sizeof(UWORD)) {
654            *(UWORD *)p = 0;
655            nbytes -= sizeof(UWORD);
656            p += sizeof(UWORD);
657        }
658    }
659    while (nbytes) {
660        *p = 0;
661        nbytes--;
662        p++;
663    }
664}
665
666/* ---------------------------------------------------------------------- */
667
668static void nh_final(nh_ctx *hc, UINT8 *result)
669/* After passing some number of data buffers to nh_update() for integration
670 * into an NH context, nh_final is called to produce a hash result. If any
671 * bytes are in the buffer hc->data, incorporate them into the
672 * NH context. Finally, add into the NH accumulation "state" the total number
673 * of bits hashed. The resulting numbers are written to the buffer "result".
674 * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
675 */
676{
677    int nh_len, nbits;
678
679    if (hc->next_data_empty != 0) {
680        nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
681                                                ~(L1_PAD_BOUNDARY - 1));
682        zero_pad(hc->data + hc->next_data_empty,
683                                          nh_len - hc->next_data_empty);
684        nh_transform(hc, hc->data, nh_len);
685        hc->bytes_hashed += hc->next_data_empty;
686    } else if (hc->bytes_hashed == 0) {
687	nh_len = L1_PAD_BOUNDARY;
688        zero_pad(hc->data, L1_PAD_BOUNDARY);
689        nh_transform(hc, hc->data, nh_len);
690    }
691
692    nbits = (hc->bytes_hashed << 3);
693    ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
694#if (UMAC_OUTPUT_LEN >= 8)
695    ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
696#endif
697#if (UMAC_OUTPUT_LEN >= 12)
698    ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
699#endif
700#if (UMAC_OUTPUT_LEN == 16)
701    ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
702#endif
703    nh_reset(hc);
704}
705
706/* ---------------------------------------------------------------------- */
707
708static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
709               UINT32 unpadded_len, UINT8 *result)
710/* All-in-one nh_update() and nh_final() equivalent.
711 * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
712 * well aligned
713 */
714{
715    UINT32 nbits;
716
717    /* Initialize the hash state */
718    nbits = (unpadded_len << 3);
719
720    ((UINT64 *)result)[0] = nbits;
721#if (UMAC_OUTPUT_LEN >= 8)
722    ((UINT64 *)result)[1] = nbits;
723#endif
724#if (UMAC_OUTPUT_LEN >= 12)
725    ((UINT64 *)result)[2] = nbits;
726#endif
727#if (UMAC_OUTPUT_LEN == 16)
728    ((UINT64 *)result)[3] = nbits;
729#endif
730
731    nh_aux(hc->nh_key, buf, result, padded_len);
732}
733
734/* ---------------------------------------------------------------------- */
735/* ---------------------------------------------------------------------- */
736/* ----- Begin UHASH Section -------------------------------------------- */
737/* ---------------------------------------------------------------------- */
738/* ---------------------------------------------------------------------- */
739
740/* UHASH is a multi-layered algorithm. Data presented to UHASH is first
741 * hashed by NH. The NH output is then hashed by a polynomial-hash layer
742 * unless the initial data to be hashed is short. After the polynomial-
743 * layer, an inner-product hash is used to produce the final UHASH output.
744 *
745 * UHASH provides two interfaces, one all-at-once and another where data
746 * buffers are presented sequentially. In the sequential interface, the
747 * UHASH client calls the routine uhash_update() as many times as necessary.
748 * When there is no more data to be fed to UHASH, the client calls
749 * uhash_final() which
750 * calculates the UHASH output. Before beginning another UHASH calculation
751 * the uhash_reset() routine must be called. The all-at-once UHASH routine,
752 * uhash(), is equivalent to the sequence of calls uhash_update() and
753 * uhash_final(); however it is optimized and should be
754 * used whenever the sequential interface is not necessary.
755 *
756 * The routine uhash_init() initializes the uhash_ctx data structure and
757 * must be called once, before any other UHASH routine.
758 */
759
760/* ---------------------------------------------------------------------- */
761/* ----- Constants and uhash_ctx ---------------------------------------- */
762/* ---------------------------------------------------------------------- */
763
764/* ---------------------------------------------------------------------- */
765/* ----- Poly hash and Inner-Product hash Constants --------------------- */
766/* ---------------------------------------------------------------------- */
767
768/* Primes and masks */
769#define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
770#define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
771#define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
772
773
774/* ---------------------------------------------------------------------- */
775
776typedef struct uhash_ctx {
777    nh_ctx hash;                          /* Hash context for L1 NH hash  */
778    UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
779    UINT64 poly_accum[STREAMS];           /* poly hash result             */
780    UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
781    UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
782    UINT32 msg_len;                       /* Total length of data passed  */
783                                          /* to uhash */
784} uhash_ctx;
785typedef struct uhash_ctx *uhash_ctx_t;
786
787/* ---------------------------------------------------------------------- */
788
789
790/* The polynomial hashes use Horner's rule to evaluate a polynomial one
791 * word at a time. As described in the specification, poly32 and poly64
792 * require keys from special domains. The following implementations exploit
793 * the special domains to avoid overflow. The results are not guaranteed to
794 * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
795 * patches any errant values.
796 */
797
798static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
799{
800    UINT32 key_hi = (UINT32)(key >> 32),
801           key_lo = (UINT32)key,
802           cur_hi = (UINT32)(cur >> 32),
803           cur_lo = (UINT32)cur,
804           x_lo,
805           x_hi;
806    UINT64 X,T,res;
807
808    X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
809    x_lo = (UINT32)X;
810    x_hi = (UINT32)(X >> 32);
811
812    res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
813
814    T = ((UINT64)x_lo << 32);
815    res += T;
816    if (res < T)
817        res += 59;
818
819    res += data;
820    if (res < data)
821        res += 59;
822
823    return res;
824}
825
826
827/* Although UMAC is specified to use a ramped polynomial hash scheme, this
828 * implementation does not handle all ramp levels. Because we don't handle
829 * the ramp up to p128 modulus in this implementation, we are limited to
830 * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
831 * bytes input to UMAC per tag, ie. 16MB).
832 */
833static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
834{
835    int i;
836    UINT64 *data=(UINT64*)data_in;
837
838    for (i = 0; i < STREAMS; i++) {
839        if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
840            hc->poly_accum[i] = poly64(hc->poly_accum[i],
841                                       hc->poly_key_8[i], p64 - 1);
842            hc->poly_accum[i] = poly64(hc->poly_accum[i],
843                                       hc->poly_key_8[i], (data[i] - 59));
844        } else {
845            hc->poly_accum[i] = poly64(hc->poly_accum[i],
846                                       hc->poly_key_8[i], data[i]);
847        }
848    }
849}
850
851
852/* ---------------------------------------------------------------------- */
853
854
855/* The final step in UHASH is an inner-product hash. The poly hash
856 * produces a result not necessarily WORD_LEN bytes long. The inner-
857 * product hash breaks the polyhash output into 16-bit chunks and
858 * multiplies each with a 36 bit key.
859 */
860
861static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
862{
863    t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
864    t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
865    t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
866    t = t + ipkp[3] * (UINT64)(UINT16)(data);
867
868    return t;
869}
870
871static UINT32 ip_reduce_p36(UINT64 t)
872{
873/* Divisionless modular reduction */
874    UINT64 ret;
875
876    ret = (t & m36) + 5 * (t >> 36);
877    if (ret >= p36)
878        ret -= p36;
879
880    /* return least significant 32 bits */
881    return (UINT32)(ret);
882}
883
884
885/* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
886 * the polyhash stage is skipped and ip_short is applied directly to the
887 * NH output.
888 */
889static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
890{
891    UINT64 t;
892    UINT64 *nhp = (UINT64 *)nh_res;
893
894    t  = ip_aux(0,ahc->ip_keys, nhp[0]);
895    STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
896#if (UMAC_OUTPUT_LEN >= 8)
897    t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
898    STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
899#endif
900#if (UMAC_OUTPUT_LEN >= 12)
901    t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
902    STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
903#endif
904#if (UMAC_OUTPUT_LEN == 16)
905    t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
906    STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
907#endif
908}
909
910/* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
911 * the polyhash stage is not skipped and ip_long is applied to the
912 * polyhash output.
913 */
914static void ip_long(uhash_ctx_t ahc, u_char *res)
915{
916    int i;
917    UINT64 t;
918
919    for (i = 0; i < STREAMS; i++) {
920        /* fix polyhash output not in Z_p64 */
921        if (ahc->poly_accum[i] >= p64)
922            ahc->poly_accum[i] -= p64;
923        t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
924        STORE_UINT32_BIG((UINT32 *)res+i,
925                         ip_reduce_p36(t) ^ ahc->ip_trans[i]);
926    }
927}
928
929
930/* ---------------------------------------------------------------------- */
931
932/* ---------------------------------------------------------------------- */
933
934/* Reset uhash context for next hash session */
935static int uhash_reset(uhash_ctx_t pc)
936{
937    nh_reset(&pc->hash);
938    pc->msg_len = 0;
939    pc->poly_accum[0] = 1;
940#if (UMAC_OUTPUT_LEN >= 8)
941    pc->poly_accum[1] = 1;
942#endif
943#if (UMAC_OUTPUT_LEN >= 12)
944    pc->poly_accum[2] = 1;
945#endif
946#if (UMAC_OUTPUT_LEN == 16)
947    pc->poly_accum[3] = 1;
948#endif
949    return 1;
950}
951
952/* ---------------------------------------------------------------------- */
953
954/* Given a pointer to the internal key needed by kdf() and a uhash context,
955 * initialize the NH context and generate keys needed for poly and inner-
956 * product hashing. All keys are endian adjusted in memory so that native
957 * loads cause correct keys to be in registers during calculation.
958 */
959static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
960{
961    int i;
962    UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
963
964    /* Zero the entire uhash context */
965    memset(ahc, 0, sizeof(uhash_ctx));
966
967    /* Initialize the L1 hash */
968    nh_init(&ahc->hash, prf_key);
969
970    /* Setup L2 hash variables */
971    kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
972    for (i = 0; i < STREAMS; i++) {
973        /* Fill keys from the buffer, skipping bytes in the buffer not
974         * used by this implementation. Endian reverse the keys if on a
975         * little-endian computer.
976         */
977        memcpy(ahc->poly_key_8+i, buf+24*i, 8);
978        endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
979        /* Mask the 64-bit keys to their special domain */
980        ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
981        ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
982    }
983
984    /* Setup L3-1 hash variables */
985    kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
986    for (i = 0; i < STREAMS; i++)
987          memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
988                                                 4*sizeof(UINT64));
989    endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
990                                                  sizeof(ahc->ip_keys));
991    for (i = 0; i < STREAMS*4; i++)
992        ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
993
994    /* Setup L3-2 hash variables    */
995    /* Fill buffer with index 4 key */
996    kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
997    endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
998                         STREAMS * sizeof(UINT32));
999    explicit_bzero(buf, sizeof(buf));
1000}
1001
1002/* ---------------------------------------------------------------------- */
1003
1004#if 0
1005static uhash_ctx_t uhash_alloc(u_char key[])
1006{
1007/* Allocate memory and force to a 16-byte boundary. */
1008    uhash_ctx_t ctx;
1009    u_char bytes_to_add;
1010    aes_int_key prf_key;
1011
1012    ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1013    if (ctx) {
1014        if (ALLOC_BOUNDARY) {
1015            bytes_to_add = ALLOC_BOUNDARY -
1016                              ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1017            ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1018            *((u_char *)ctx - 1) = bytes_to_add;
1019        }
1020        aes_key_setup(key,prf_key);
1021        uhash_init(ctx, prf_key);
1022    }
1023    return (ctx);
1024}
1025#endif
1026
1027/* ---------------------------------------------------------------------- */
1028
1029#if 0
1030static int uhash_free(uhash_ctx_t ctx)
1031{
1032/* Free memory allocated by uhash_alloc */
1033    u_char bytes_to_sub;
1034
1035    if (ctx) {
1036        if (ALLOC_BOUNDARY) {
1037            bytes_to_sub = *((u_char *)ctx - 1);
1038            ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1039        }
1040        free(ctx);
1041    }
1042    return (1);
1043}
1044#endif
1045/* ---------------------------------------------------------------------- */
1046
1047static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1048/* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1049 * hash each one with NH, calling the polyhash on each NH output.
1050 */
1051{
1052    UWORD bytes_hashed, bytes_remaining;
1053    UINT64 result_buf[STREAMS];
1054    UINT8 *nh_result = (UINT8 *)&result_buf;
1055
1056    if (ctx->msg_len + len <= L1_KEY_LEN) {
1057        nh_update(&ctx->hash, (const UINT8 *)input, len);
1058        ctx->msg_len += len;
1059    } else {
1060
1061         bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1062         if (ctx->msg_len == L1_KEY_LEN)
1063             bytes_hashed = L1_KEY_LEN;
1064
1065         if (bytes_hashed + len >= L1_KEY_LEN) {
1066
1067             /* If some bytes have been passed to the hash function      */
1068             /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1069             /* bytes to complete the current nh_block.                  */
1070             if (bytes_hashed) {
1071                 bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1072                 nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1073                 nh_final(&ctx->hash, nh_result);
1074                 ctx->msg_len += bytes_remaining;
1075                 poly_hash(ctx,(UINT32 *)nh_result);
1076                 len -= bytes_remaining;
1077                 input += bytes_remaining;
1078             }
1079
1080             /* Hash directly from input stream if enough bytes */
1081             while (len >= L1_KEY_LEN) {
1082                 nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1083                                   L1_KEY_LEN, nh_result);
1084                 ctx->msg_len += L1_KEY_LEN;
1085                 len -= L1_KEY_LEN;
1086                 input += L1_KEY_LEN;
1087                 poly_hash(ctx,(UINT32 *)nh_result);
1088             }
1089         }
1090
1091         /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1092         if (len) {
1093             nh_update(&ctx->hash, (const UINT8 *)input, len);
1094             ctx->msg_len += len;
1095         }
1096     }
1097
1098    return (1);
1099}
1100
1101/* ---------------------------------------------------------------------- */
1102
1103static int uhash_final(uhash_ctx_t ctx, u_char *res)
1104/* Incorporate any pending data, pad, and generate tag */
1105{
1106    UINT64 result_buf[STREAMS];
1107    UINT8 *nh_result = (UINT8 *)&result_buf;
1108
1109    if (ctx->msg_len > L1_KEY_LEN) {
1110        if (ctx->msg_len % L1_KEY_LEN) {
1111            nh_final(&ctx->hash, nh_result);
1112            poly_hash(ctx,(UINT32 *)nh_result);
1113        }
1114        ip_long(ctx, res);
1115    } else {
1116        nh_final(&ctx->hash, nh_result);
1117        ip_short(ctx,nh_result, res);
1118    }
1119    uhash_reset(ctx);
1120    return (1);
1121}
1122
1123/* ---------------------------------------------------------------------- */
1124
1125#if 0
1126static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1127/* assumes that msg is in a writable buffer of length divisible by */
1128/* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1129{
1130    UINT8 nh_result[STREAMS*sizeof(UINT64)];
1131    UINT32 nh_len;
1132    int extra_zeroes_needed;
1133
1134    /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1135     * the polyhash.
1136     */
1137    if (len <= L1_KEY_LEN) {
1138	if (len == 0)                  /* If zero length messages will not */
1139		nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1140	else
1141		nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1142        extra_zeroes_needed = nh_len - len;
1143        zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1144        nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1145        ip_short(ahc,nh_result, res);
1146    } else {
1147        /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1148         * output to poly_hash().
1149         */
1150        do {
1151            nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1152            poly_hash(ahc,(UINT32 *)nh_result);
1153            len -= L1_KEY_LEN;
1154            msg += L1_KEY_LEN;
1155        } while (len >= L1_KEY_LEN);
1156        if (len) {
1157            nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1158            extra_zeroes_needed = nh_len - len;
1159            zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1160            nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1161            poly_hash(ahc,(UINT32 *)nh_result);
1162        }
1163
1164        ip_long(ahc, res);
1165    }
1166
1167    uhash_reset(ahc);
1168    return 1;
1169}
1170#endif
1171
1172/* ---------------------------------------------------------------------- */
1173/* ---------------------------------------------------------------------- */
1174/* ----- Begin UMAC Section --------------------------------------------- */
1175/* ---------------------------------------------------------------------- */
1176/* ---------------------------------------------------------------------- */
1177
1178/* The UMAC interface has two interfaces, an all-at-once interface where
1179 * the entire message to be authenticated is passed to UMAC in one buffer,
1180 * and a sequential interface where the message is presented a little at a
1181 * time. The all-at-once is more optimized than the sequential version and
1182 * should be preferred when the sequential interface is not required.
1183 */
1184struct umac_ctx {
1185    uhash_ctx hash;          /* Hash function for message compression    */
1186    pdf_ctx pdf;             /* PDF for hashed output                    */
1187    void *free_ptr;          /* Address to free this struct via          */
1188} umac_ctx;
1189
1190/* ---------------------------------------------------------------------- */
1191
1192#if 0
1193int umac_reset(struct umac_ctx *ctx)
1194/* Reset the hash function to begin a new authentication.        */
1195{
1196    uhash_reset(&ctx->hash);
1197    return (1);
1198}
1199#endif
1200
1201/* ---------------------------------------------------------------------- */
1202
1203int umac_delete(struct umac_ctx *ctx)
1204/* Deallocate the ctx structure */
1205{
1206    if (ctx) {
1207        if (ALLOC_BOUNDARY)
1208            ctx = (struct umac_ctx *)ctx->free_ptr;
1209        freezero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY);
1210    }
1211    return (1);
1212}
1213
1214/* ---------------------------------------------------------------------- */
1215
1216struct umac_ctx *umac_new(const u_char key[])
1217/* Dynamically allocate a umac_ctx struct, initialize variables,
1218 * generate subkeys from key. Align to 16-byte boundary.
1219 */
1220{
1221    struct umac_ctx *ctx, *octx;
1222    size_t bytes_to_add;
1223    aes_int_key prf_key;
1224
1225    octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1226    if (ctx) {
1227        if (ALLOC_BOUNDARY) {
1228            bytes_to_add = ALLOC_BOUNDARY -
1229                              ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1230            ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1231        }
1232        ctx->free_ptr = octx;
1233        aes_key_setup(key, prf_key);
1234        pdf_init(&ctx->pdf, prf_key);
1235        uhash_init(&ctx->hash, prf_key);
1236        explicit_bzero(prf_key, sizeof(prf_key));
1237    }
1238
1239    return (ctx);
1240}
1241
1242/* ---------------------------------------------------------------------- */
1243
1244int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1245/* Incorporate any pending data, pad, and generate tag */
1246{
1247    uhash_final(&ctx->hash, (u_char *)tag);
1248    pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1249
1250    return (1);
1251}
1252
1253/* ---------------------------------------------------------------------- */
1254
1255int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1256/* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1257/* hash each one, calling the PDF on the hashed output whenever the hash- */
1258/* output buffer is full.                                                 */
1259{
1260    uhash_update(&ctx->hash, input, len);
1261    return (1);
1262}
1263
1264/* ---------------------------------------------------------------------- */
1265
1266#if 0
1267int umac(struct umac_ctx *ctx, u_char *input,
1268         long len, u_char tag[],
1269         u_char nonce[8])
1270/* All-in-one version simply calls umac_update() and umac_final().        */
1271{
1272    uhash(&ctx->hash, input, len, (u_char *)tag);
1273    pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1274
1275    return (1);
1276}
1277#endif
1278
1279/* ---------------------------------------------------------------------- */
1280/* ---------------------------------------------------------------------- */
1281/* ----- End UMAC Section ----------------------------------------------- */
1282/* ---------------------------------------------------------------------- */
1283/* ---------------------------------------------------------------------- */
1284