umac.c

   1 /* $OpenBSD: umac.c,v 1.3 2008/05/12 20:52:20 pvalchev Exp $ */
   2 /* -----------------------------------------------------------------------
   3  *
   4  * umac.c -- C Implementation UMAC Message Authentication
   5  *
   6  * Version 0.93b of rfc4418.txt -- 2006 July 18
   7  *
   8  * For a full description of UMAC message authentication see the UMAC
   9  * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac
  10  * Please report bugs and suggestions to the UMAC webpage.
  11  *
  12  * Copyright (c) 1999-2006 Ted Krovetz
  13  *
  14  * Permission to use, copy, modify, and distribute this software and
  15  * its documentation for any purpose and with or without fee, is hereby
  16  * granted provided that the above copyright notice appears in all copies
  17  * and in supporting documentation, and that the name of the copyright
  18  * holder not be used in advertising or publicity pertaining to
  19  * distribution of the software without specific, written prior permission.
  20  *
  21  * Comments should be directed to Ted Krovetz (tdk@acm.org)
  22  *
  23  * ---------------------------------------------------------------------- */
  24
  25  /* ////////////////////// IMPORTANT NOTES /////////////////////////////////
  26   *
  27   * 1) This version does not work properly on messages larger than 16MB
  28   *
  29   * 2) If you set the switch to use SSE2, then all data must be 16-byte
  30   *    aligned
  31   *
  32   * 3) When calling the function umac(), it is assumed that msg is in
  33   * a writable buffer of length divisible by 32 bytes. The message itself
  34   * does not have to fill the entire buffer, but bytes beyond msg may be
  35   * zeroed.
  36   *
  37   * 4) Three free AES implementations are supported by this implementation of
  38   * UMAC. Paulo Barreto's version is in the public domain and can be found
  39   * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for
  40   * "Barreto"). The only two files needed are rijndael-alg-fst.c and
  41   * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU
  42   * Public lisence at http://fp.gladman.plus.com/AES/index.htm. It
  43   * includes a fast IA-32 assembly version. The OpenSSL crypo library is
  44   * the third.
  45   *
  46   * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes
  47   * produced under gcc with optimizations set -O3 or higher. Dunno why.
  48   *
  49   /////////////////////////////////////////////////////////////////////// */
  50
  51 /* ---------------------------------------------------------------------- */
  52 /* --- User Switches ---------------------------------------------------- */
  53 /* ---------------------------------------------------------------------- */
  54
  55 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
  56 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
  57 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
  58 /* #define SSE2                0  Is SSE2 is available?                   */
  59 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
  60 /* #define UMAC_AE_SUPPORT     0  Enable auhthenticated encrytion         */
  61
  62 /* ---------------------------------------------------------------------- */
  63 /* -- Global Includes --------------------------------------------------- */
  64 /* ---------------------------------------------------------------------- */
  65
  66 #include "includes.h"
  67 #include <sys/types.h>
  68
  69 #include "xmalloc.h"
  70 #include "umac.h"
  71 #include <string.h>
  72 #include <stdlib.h>
  73 #include <stddef.h>
  74
  75 /* ---------------------------------------------------------------------- */
  76 /* --- Primitive Data Types ---                                           */
  77 /* ---------------------------------------------------------------------- */
  78
  79 /* The following assumptions may need change on your system */
  80 typedef u_int8_t        UINT8;  /* 1 byte   */
  81 typedef u_int16_t       UINT16; /* 2 byte   */
  82 typedef u_int32_t       UINT32; /* 4 byte   */
  83 typedef u_int64_t       UINT64; /* 8 bytes  */
  84 typedef unsigned int    UWORD;  /* Register */
  85
  86 /* ---------------------------------------------------------------------- */
  87 /* --- Constants -------------------------------------------------------- */
  88 /* ---------------------------------------------------------------------- */
  89
  90 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
  91
  92 /* Message "words" are read from memory in an endian-specific manner.     */
  93 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
  94 /* be set true if the host computer is little-endian.                     */
  95
  96 #if BYTE_ORDER == LITTLE_ENDIAN
  97 #define __LITTLE_ENDIAN__ 1
  98 #else
  99 #define __LITTLE_ENDIAN__ 0
 100 #endif
 101
 102 /* ---------------------------------------------------------------------- */
 103 /* ---------------------------------------------------------------------- */
 104 /* ----- Architecture Specific ------------------------------------------ */
 105 /* ---------------------------------------------------------------------- */
 106 /* ---------------------------------------------------------------------- */
 107
 108
 109 /* ---------------------------------------------------------------------- */
 110 /* ---------------------------------------------------------------------- */
 111 /* ----- Primitive Routines --------------------------------------------- */
 112 /* ---------------------------------------------------------------------- */
 113 /* ---------------------------------------------------------------------- */
 114
 115
 116 /* ---------------------------------------------------------------------- */
 117 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
 118 /* ---------------------------------------------------------------------- */
 119
 120 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
 121
 122 /* ---------------------------------------------------------------------- */
 123 /* --- Endian Conversion --- Forcing assembly on some platforms           */
 124 /* ---------------------------------------------------------------------- */
 125
 126 #if HAVE_SWAP32
 127 #define LOAD_UINT32_REVERSED(p)         (swap32(*(UINT32 *)(p)))
 128 #define STORE_UINT32_REVERSED(p,v)      (*(UINT32 *)(p) = swap32(v))
 129 #else /* HAVE_SWAP32 */
 130
 131 static UINT32 LOAD_UINT32_REVERSED(void *ptr)
 132 {
 133     UINT32 temp = *(UINT32 *)ptr;
 134     temp = (temp >> 24) | ((temp & 0x00FF0000) >> 8 )
 135          | ((temp & 0x0000FF00) << 8 ) | (temp << 24);
 136     return (UINT32)temp;
 137 }
 138
 139 # if (__LITTLE_ENDIAN__)
 140 static void STORE_UINT32_REVERSED(void *ptr, UINT32 x)
 141 {
 142     UINT32 i = (UINT32)x;
 143     *(UINT32 *)ptr = (i >> 24) | ((i & 0x00FF0000) >> 8 )
 144                    | ((i & 0x0000FF00) << 8 ) | (i << 24);
 145 }
 146 # endif /* __LITTLE_ENDIAN */
 147 #endif /* HAVE_SWAP32 */
 148
 149 /* The following definitions use the above reversal-primitives to do the right
 150  * thing on endian specific load and stores.
 151  */
 152
 153 #if (__LITTLE_ENDIAN__)
 154 #define LOAD_UINT32_LITTLE(ptr)     (*(UINT32 *)(ptr))
 155 #define STORE_UINT32_BIG(ptr,x)     STORE_UINT32_REVERSED(ptr,x)
 156 #else
 157 #define LOAD_UINT32_LITTLE(ptr)     LOAD_UINT32_REVERSED(ptr)
 158 #define STORE_UINT32_BIG(ptr,x)     (*(UINT32 *)(ptr) = (UINT32)(x))
 159 #endif
 160
 161 /* ---------------------------------------------------------------------- */
 162 /* ---------------------------------------------------------------------- */
 163 /* ----- Begin KDF & PDF Section ---------------------------------------- */
 164 /* ---------------------------------------------------------------------- */
 165 /* ---------------------------------------------------------------------- */
 166
 167 /* UMAC uses AES with 16 byte block and key lengths */
 168 #define AES_BLOCK_LEN  16
 169
 170 /* OpenSSL's AES */
 171 #include "openbsd-compat/openssl-compat.h"
 172 #ifndef USE_BUILTIN_RIJNDAEL
 173 # include <openssl/aes.h>
 174 #endif
 175 typedef AES_KEY aes_int_key[1];
 176 #define aes_encryption(in,out,int_key)                  \
 177   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
 178 #define aes_key_setup(key,int_key)                      \
 179   AES_set_encrypt_key((u_char *)(key),UMAC_KEY_LEN*8,int_key)
 180
 181 /* The user-supplied UMAC key is stretched using AES in a counter
 182  * mode to supply all random bits needed by UMAC. The kdf function takes
 183  * an AES internal key representation 'key' and writes a stream of
 184  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
 185  * 'ndx' causes a distinct byte stream.
 186  */
 187 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
 188 {
 189     UINT8 in_buf[AES_BLOCK_LEN] = {0};
 190     UINT8 out_buf[AES_BLOCK_LEN];
 191     UINT8 *dst_buf = (UINT8 *)bufp;
 192     int i;
 193
 194     /* Setup the initial value */
 195     in_buf[AES_BLOCK_LEN-9] = ndx;
 196     in_buf[AES_BLOCK_LEN-1] = i = 1;
 197
 198     while (nbytes >= AES_BLOCK_LEN) {
 199         aes_encryption(in_buf, out_buf, key);
 200         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
 201         in_buf[AES_BLOCK_LEN-1] = ++i;
 202         nbytes -= AES_BLOCK_LEN;
 203         dst_buf += AES_BLOCK_LEN;
 204     }
 205     if (nbytes) {
 206         aes_encryption(in_buf, out_buf, key);
 207         memcpy(dst_buf,out_buf,nbytes);
 208     }
 209 }
 210
 211 /* The final UHASH result is XOR'd with the output of a pseudorandom
 212  * function. Here, we use AES to generate random output and
 213  * xor the appropriate bytes depending on the last bits of nonce.
 214  * This scheme is optimized for sequential, increasing big-endian nonces.
 215  */
 216
 217 typedef struct {
 218     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
 219     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
 220     aes_int_key prf_key;         /* Expanded AES key for PDF          */
 221 } pdf_ctx;
 222
 223 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
 224 {
 225     UINT8 buf[UMAC_KEY_LEN];
 226
 227     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
 228     aes_key_setup(buf, pc->prf_key);
 229
 230     /* Initialize pdf and cache */
 231     memset(pc->nonce, 0, sizeof(pc->nonce));
 232     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 233 }
 234
 235 static void pdf_gen_xor(pdf_ctx *pc, 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
 250     UINT8 tmp_nonce_lo[4];
 251 #if LOW_BIT_MASK != 0
 252     int ndx = nonce[7] & LOW_BIT_MASK;
 253 #endif
 254     *(UINT32 *)tmp_nonce_lo = ((UINT32 *)nonce)[1];
 255     tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
 256
 257     if ( (((UINT32 *)tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
 258          (((UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
 259     {
 260         ((UINT32 *)pc->nonce)[0] = ((UINT32 *)nonce)[0];
 261         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)tmp_nonce_lo)[0];
 262         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 263     }
 264
 265 #if (UMAC_OUTPUT_LEN == 4)
 266     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
 267 #elif (UMAC_OUTPUT_LEN == 8)
 268     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
 269 #elif (UMAC_OUTPUT_LEN == 12)
 270     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 271     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
 272 #elif (UMAC_OUTPUT_LEN == 16)
 273     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 274     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
 275 #endif
 276 }
 277
 278 /* ---------------------------------------------------------------------- */
 279 /* ---------------------------------------------------------------------- */
 280 /* ----- Begin NH Hash Section ------------------------------------------ */
 281 /* ---------------------------------------------------------------------- */
 282 /* ---------------------------------------------------------------------- */
 283
 284 /* The NH-based hash functions used in UMAC are described in the UMAC paper
 285  * and specification, both of which can be found at the UMAC website.
 286  * The interface to this implementation has two
 287  * versions, one expects the entire message being hashed to be passed
 288  * in a single buffer and returns the hash result immediately. The second
 289  * allows the message to be passed in a sequence of buffers. In the
 290  * muliple-buffer interface, the client calls the routine nh_update() as
 291  * many times as necessary. When there is no more data to be fed to the
 292  * hash, the client calls nh_final() which calculates the hash output.
 293  * Before beginning another hash calculation the nh_reset() routine
 294  * must be called. The single-buffer routine, nh(), is equivalent to
 295  * the sequence of calls nh_update() and nh_final(); however it is
 296  * optimized and should be prefered whenever the multiple-buffer interface
 297  * is not necessary. When using either interface, it is the client's
 298  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
 299  *
 300  * The routine nh_init() initializes the nh_ctx data structure and
 301  * must be called once, before any other PDF routine.
 302  */
 303
 304  /* The "nh_aux" routines do the actual NH hashing work. They
 305   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
 306   * produce output for all STREAMS NH iterations in one call,
 307   * allowing the parallel implementation of the streams.
 308   */
 309
 310 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
 311 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
 312 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
 313 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
 314 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
 315 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
 316
 317 typedef struct {
 318     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
 319     UINT8  data   [HASH_BUF_BYTES];    /* Incomming data buffer           */
 320     int next_data_empty;    /* Bookeeping variable for data buffer.       */
 321     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
 322     UINT64 state[STREAMS];               /* on-line state     */
 323 } nh_ctx;
 324
 325
 326 #if (UMAC_OUTPUT_LEN == 4)
 327
 328 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 329 /* NH hashing primitive. Previous (partial) hash result is loaded and
 330 * then stored via hp pointer. The length of the data pointed at by "dp",
 331 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
 332 * is expected to be endian compensated in memory at key setup.
 333 */
 334 {
 335     UINT64 h;
 336     UWORD c = dlen / 32;
 337     UINT32 *k = (UINT32 *)kp;
 338     UINT32 *d = (UINT32 *)dp;
 339     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 340     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
 341
 342     h = *((UINT64 *)hp);
 343     do {
 344         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 345         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 346         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 347         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 348         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 349         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 350         h += MUL64((k0 + d0), (k4 + d4));
 351         h += MUL64((k1 + d1), (k5 + d5));
 352         h += MUL64((k2 + d2), (k6 + d6));
 353         h += MUL64((k3 + d3), (k7 + d7));
 354
 355         d += 8;
 356         k += 8;
 357     } while (--c);
 358   *((UINT64 *)hp) = h;
 359 }
 360
 361 #elif (UMAC_OUTPUT_LEN == 8)
 362
 363 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 364 /* Same as previous nh_aux, but two streams are handled in one pass,
 365  * reading and writing 16 bytes of hash-state per call.
 366  */
 367 {
 368   UINT64 h1,h2;
 369   UWORD c = dlen / 32;
 370   UINT32 *k = (UINT32 *)kp;
 371   UINT32 *d = (UINT32 *)dp;
 372   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 373   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 374         k8,k9,k10,k11;
 375
 376   h1 = *((UINT64 *)hp);
 377   h2 = *((UINT64 *)hp + 1);
 378   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 379   do {
 380     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 381     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 382     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 383     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 384     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 385     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 386
 387     h1 += MUL64((k0 + d0), (k4 + d4));
 388     h2 += MUL64((k4 + d0), (k8 + d4));
 389
 390     h1 += MUL64((k1 + d1), (k5 + d5));
 391     h2 += MUL64((k5 + d1), (k9 + d5));
 392
 393     h1 += MUL64((k2 + d2), (k6 + d6));
 394     h2 += MUL64((k6 + d2), (k10 + d6));
 395
 396     h1 += MUL64((k3 + d3), (k7 + d7));
 397     h2 += MUL64((k7 + d3), (k11 + d7));
 398
 399     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 400
 401     d += 8;
 402     k += 8;
 403   } while (--c);
 404   ((UINT64 *)hp)[0] = h1;
 405   ((UINT64 *)hp)[1] = h2;
 406 }
 407
 408 #elif (UMAC_OUTPUT_LEN == 12)
 409
 410 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 411 /* Same as previous nh_aux, but two streams are handled in one pass,
 412  * reading and writing 24 bytes of hash-state per call.
 413 */
 414 {
 415     UINT64 h1,h2,h3;
 416     UWORD c = dlen / 32;
 417     UINT32 *k = (UINT32 *)kp;
 418     UINT32 *d = (UINT32 *)dp;
 419     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 420     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 421         k8,k9,k10,k11,k12,k13,k14,k15;
 422
 423     h1 = *((UINT64 *)hp);
 424     h2 = *((UINT64 *)hp + 1);
 425     h3 = *((UINT64 *)hp + 2);
 426     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 427     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 428     do {
 429         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 430         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 431         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 432         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 433         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 434         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 435
 436         h1 += MUL64((k0 + d0), (k4 + d4));
 437         h2 += MUL64((k4 + d0), (k8 + d4));
 438         h3 += MUL64((k8 + d0), (k12 + d4));
 439
 440         h1 += MUL64((k1 + d1), (k5 + d5));
 441         h2 += MUL64((k5 + d1), (k9 + d5));
 442         h3 += MUL64((k9 + d1), (k13 + d5));
 443
 444         h1 += MUL64((k2 + d2), (k6 + d6));
 445         h2 += MUL64((k6 + d2), (k10 + d6));
 446         h3 += MUL64((k10 + d2), (k14 + d6));
 447
 448         h1 += MUL64((k3 + d3), (k7 + d7));
 449         h2 += MUL64((k7 + d3), (k11 + d7));
 450         h3 += MUL64((k11 + d3), (k15 + d7));
 451
 452         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 453         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 454
 455         d += 8;
 456         k += 8;
 457     } while (--c);
 458     ((UINT64 *)hp)[0] = h1;
 459     ((UINT64 *)hp)[1] = h2;
 460     ((UINT64 *)hp)[2] = h3;
 461 }
 462
 463 #elif (UMAC_OUTPUT_LEN == 16)
 464
 465 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 466 /* Same as previous nh_aux, but two streams are handled in one pass,
 467  * reading and writing 24 bytes of hash-state per call.
 468 */
 469 {
 470     UINT64 h1,h2,h3,h4;
 471     UWORD c = dlen / 32;
 472     UINT32 *k = (UINT32 *)kp;
 473     UINT32 *d = (UINT32 *)dp;
 474     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 475     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 476         k8,k9,k10,k11,k12,k13,k14,k15,
 477         k16,k17,k18,k19;
 478
 479     h1 = *((UINT64 *)hp);
 480     h2 = *((UINT64 *)hp + 1);
 481     h3 = *((UINT64 *)hp + 2);
 482     h4 = *((UINT64 *)hp + 3);
 483     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 484     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 485     do {
 486         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 487         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 488         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 489         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 490         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 491         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 492         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
 493
 494         h1 += MUL64((k0 + d0), (k4 + d4));
 495         h2 += MUL64((k4 + d0), (k8 + d4));
 496         h3 += MUL64((k8 + d0), (k12 + d4));
 497         h4 += MUL64((k12 + d0), (k16 + d4));
 498
 499         h1 += MUL64((k1 + d1), (k5 + d5));
 500         h2 += MUL64((k5 + d1), (k9 + d5));
 501         h3 += MUL64((k9 + d1), (k13 + d5));
 502         h4 += MUL64((k13 + d1), (k17 + d5));
 503
 504         h1 += MUL64((k2 + d2), (k6 + d6));
 505         h2 += MUL64((k6 + d2), (k10 + d6));
 506         h3 += MUL64((k10 + d2), (k14 + d6));
 507         h4 += MUL64((k14 + d2), (k18 + d6));
 508
 509         h1 += MUL64((k3 + d3), (k7 + d7));
 510         h2 += MUL64((k7 + d3), (k11 + d7));
 511         h3 += MUL64((k11 + d3), (k15 + d7));
 512         h4 += MUL64((k15 + d3), (k19 + d7));
 513
 514         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 515         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 516         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
 517
 518         d += 8;
 519         k += 8;
 520     } while (--c);
 521     ((UINT64 *)hp)[0] = h1;
 522     ((UINT64 *)hp)[1] = h2;
 523     ((UINT64 *)hp)[2] = h3;
 524     ((UINT64 *)hp)[3] = h4;
 525 }
 526
 527 /* ---------------------------------------------------------------------- */
 528 #endif  /* UMAC_OUTPUT_LENGTH */
 529 /* ---------------------------------------------------------------------- */
 530
 531
 532 /* ---------------------------------------------------------------------- */
 533
 534 static void nh_transform(nh_ctx *hc, UINT8 *buf, UINT32 nbytes)
 535 /* This function is a wrapper for the primitive NH hash functions. It takes
 536  * as argument "hc" the current hash context and a buffer which must be a
 537  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
 538  * appropriately according to how much message has been hashed already.
 539  */
 540 {
 541     UINT8 *key;
 542
 543     key = hc->nh_key + hc->bytes_hashed;
 544     nh_aux(key, buf, hc->state, nbytes);
 545 }
 546
 547 /* ---------------------------------------------------------------------- */
 548
 549 #if (__LITTLE_ENDIAN__)
 550 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
 551 /* We endian convert the keys on little-endian computers to               */
 552 /* compensate for the lack of big-endian memory reads during hashing.     */
 553 {
 554     UWORD iters = num_bytes / bpw;
 555     if (bpw == 4) {
 556         UINT32 *p = (UINT32 *)buf;
 557         do {
 558             *p = LOAD_UINT32_REVERSED(p);
 559             p++;
 560         } while (--iters);
 561     } else if (bpw == 8) {
 562         UINT32 *p = (UINT32 *)buf;
 563         UINT32 t;
 564         do {
 565             t = LOAD_UINT32_REVERSED(p+1);
 566             p[1] = LOAD_UINT32_REVERSED(p);
 567             p[0] = t;
 568             p += 2;
 569         } while (--iters);
 570     }
 571 }
 572 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
 573 #else
 574 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
 575 #endif
 576
 577 /* ---------------------------------------------------------------------- */
 578
 579 static void nh_reset(nh_ctx *hc)
 580 /* Reset nh_ctx to ready for hashing of new data */
 581 {
 582     hc->bytes_hashed = 0;
 583     hc->next_data_empty = 0;
 584     hc->state[0] = 0;
 585 #if (UMAC_OUTPUT_LEN >= 8)
 586     hc->state[1] = 0;
 587 #endif
 588 #if (UMAC_OUTPUT_LEN >= 12)
 589     hc->state[2] = 0;
 590 #endif
 591 #if (UMAC_OUTPUT_LEN == 16)
 592     hc->state[3] = 0;
 593 #endif
 594
 595 }
 596
 597 /* ---------------------------------------------------------------------- */
 598
 599 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
 600 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
 601 {
 602     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
 603     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
 604     nh_reset(hc);
 605 }
 606
 607 /* ---------------------------------------------------------------------- */
 608
 609 static void nh_update(nh_ctx *hc, UINT8 *buf, UINT32 nbytes)
 610 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
 611 /* even multiple of HASH_BUF_BYTES.                                       */
 612 {
 613     UINT32 i,j;
 614
 615     j = hc->next_data_empty;
 616     if ((j + nbytes) >= HASH_BUF_BYTES) {
 617         if (j) {
 618             i = HASH_BUF_BYTES - j;
 619             memcpy(hc->data+j, buf, i);
 620             nh_transform(hc,hc->data,HASH_BUF_BYTES);
 621             nbytes -= i;
 622             buf += i;
 623             hc->bytes_hashed += HASH_BUF_BYTES;
 624         }
 625         if (nbytes >= HASH_BUF_BYTES) {
 626             i = nbytes & ~(HASH_BUF_BYTES - 1);
 627             nh_transform(hc, buf, i);
 628             nbytes -= i;
 629             buf += i;
 630             hc->bytes_hashed += i;
 631         }
 632         j = 0;
 633     }
 634     memcpy(hc->data + j, buf, nbytes);
 635     hc->next_data_empty = j + nbytes;
 636 }
 637
 638 /* ---------------------------------------------------------------------- */
 639
 640 static void zero_pad(UINT8 *p, int nbytes)
 641 {
 642 /* Write "nbytes" of zeroes, beginning at "p" */
 643     if (nbytes >= (int)sizeof(UWORD)) {
 644         while ((ptrdiff_t)p % sizeof(UWORD)) {
 645             *p = 0;
 646             nbytes--;
 647             p++;
 648         }
 649         while (nbytes >= (int)sizeof(UWORD)) {
 650             *(UWORD *)p = 0;
 651             nbytes -= sizeof(UWORD);
 652             p += sizeof(UWORD);
 653         }
 654     }
 655     while (nbytes) {
 656         *p = 0;
 657         nbytes--;
 658         p++;
 659     }
 660 }
 661
 662 /* ---------------------------------------------------------------------- */
 663
 664 static void nh_final(nh_ctx *hc, UINT8 *result)
 665 /* After passing some number of data buffers to nh_update() for integration
 666  * into an NH context, nh_final is called to produce a hash result. If any
 667  * bytes are in the buffer hc->data, incorporate them into the
 668  * NH context. Finally, add into the NH accumulation "state" the total number
 669  * of bits hashed. The resulting numbers are written to the buffer "result".
 670  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
 671  */
 672 {
 673     int nh_len, nbits;
 674
 675     if (hc->next_data_empty != 0) {
 676         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
 677                                                 ~(L1_PAD_BOUNDARY - 1));
 678         zero_pad(hc->data + hc->next_data_empty,
 679                                           nh_len - hc->next_data_empty);
 680         nh_transform(hc, hc->data, nh_len);
 681         hc->bytes_hashed += hc->next_data_empty;
 682     } else if (hc->bytes_hashed == 0) {
 683         nh_len = L1_PAD_BOUNDARY;
 684         zero_pad(hc->data, L1_PAD_BOUNDARY);
 685         nh_transform(hc, hc->data, nh_len);
 686     }
 687
 688     nbits = (hc->bytes_hashed << 3);
 689     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
 690 #if (UMAC_OUTPUT_LEN >= 8)
 691     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
 692 #endif
 693 #if (UMAC_OUTPUT_LEN >= 12)
 694     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
 695 #endif
 696 #if (UMAC_OUTPUT_LEN == 16)
 697     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
 698 #endif
 699     nh_reset(hc);
 700 }
 701
 702 /* ---------------------------------------------------------------------- */
 703
 704 static void nh(nh_ctx *hc, UINT8 *buf, UINT32 padded_len,
 705                UINT32 unpadded_len, UINT8 *result)
 706 /* All-in-one nh_update() and nh_final() equivalent.
 707  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
 708  * well aligned
 709  */
 710 {
 711     UINT32 nbits;
 712
 713     /* Initialize the hash state */
 714     nbits = (unpadded_len << 3);
 715
 716     ((UINT64 *)result)[0] = nbits;
 717 #if (UMAC_OUTPUT_LEN >= 8)
 718     ((UINT64 *)result)[1] = nbits;
 719 #endif
 720 #if (UMAC_OUTPUT_LEN >= 12)
 721     ((UINT64 *)result)[2] = nbits;
 722 #endif
 723 #if (UMAC_OUTPUT_LEN == 16)
 724     ((UINT64 *)result)[3] = nbits;
 725 #endif
 726
 727     nh_aux(hc->nh_key, buf, result, padded_len);
 728 }
 729
 730 /* ---------------------------------------------------------------------- */
 731 /* ---------------------------------------------------------------------- */
 732 /* ----- Begin UHASH Section -------------------------------------------- */
 733 /* ---------------------------------------------------------------------- */
 734 /* ---------------------------------------------------------------------- */
 735
 736 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
 737  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
 738  * unless the initial data to be hashed is short. After the polynomial-
 739  * layer, an inner-product hash is used to produce the final UHASH output.
 740  *
 741  * UHASH provides two interfaces, one all-at-once and another where data
 742  * buffers are presented sequentially. In the sequential interface, the
 743  * UHASH client calls the routine uhash_update() as many times as necessary.
 744  * When there is no more data to be fed to UHASH, the client calls
 745  * uhash_final() which
 746  * calculates the UHASH output. Before beginning another UHASH calculation
 747  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
 748  * uhash(), is equivalent to the sequence of calls uhash_update() and
 749  * uhash_final(); however it is optimized and should be
 750  * used whenever the sequential interface is not necessary.
 751  *
 752  * The routine uhash_init() initializes the uhash_ctx data structure and
 753  * must be called once, before any other UHASH routine.
 754  */
 755
 756 /* ---------------------------------------------------------------------- */
 757 /* ----- Constants and uhash_ctx ---------------------------------------- */
 758 /* ---------------------------------------------------------------------- */
 759
 760 /* ---------------------------------------------------------------------- */
 761 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
 762 /* ---------------------------------------------------------------------- */
 763
 764 /* Primes and masks */
 765 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
 766 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
 767 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
 768
 769
 770 /* ---------------------------------------------------------------------- */
 771
 772 typedef struct uhash_ctx {
 773     nh_ctx hash;                          /* Hash context for L1 NH hash  */
 774     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
 775     UINT64 poly_accum[STREAMS];           /* poly hash result             */
 776     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
 777     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
 778     UINT32 msg_len;                       /* Total length of data passed  */
 779                                           /* to uhash */
 780 } uhash_ctx;
 781 typedef struct uhash_ctx *uhash_ctx_t;
 782
 783 /* ---------------------------------------------------------------------- */
 784
 785
 786 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
 787  * word at a time. As described in the specification, poly32 and poly64
 788  * require keys from special domains. The following implementations exploit
 789  * the special domains to avoid overflow. The results are not guaranteed to
 790  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
 791  * patches any errant values.
 792  */
 793
 794 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
 795 {
 796     UINT32 key_hi = (UINT32)(key >> 32),
 797            key_lo = (UINT32)key,
 798            cur_hi = (UINT32)(cur >> 32),
 799            cur_lo = (UINT32)cur,
 800            x_lo,
 801            x_hi;
 802     UINT64 X,T,res;
 803
 804     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
 805     x_lo = (UINT32)X;
 806     x_hi = (UINT32)(X >> 32);
 807
 808     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
 809
 810     T = ((UINT64)x_lo << 32);
 811     res += T;
 812     if (res < T)
 813         res += 59;
 814
 815     res += data;
 816     if (res < data)
 817         res += 59;
 818
 819     return res;
 820 }
 821
 822
 823 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
 824  * implementation does not handle all ramp levels. Because we don't handle
 825  * the ramp up to p128 modulus in this implementation, we are limited to
 826  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
 827  * bytes input to UMAC per tag, ie. 16MB).
 828  */
 829 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
 830 {
 831     int i;
 832     UINT64 *data=(UINT64*)data_in;
 833
 834     for (i = 0; i < STREAMS; i++) {
 835         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
 836             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 837                                        hc->poly_key_8[i], p64 - 1);
 838             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 839                                        hc->poly_key_8[i], (data[i] - 59));
 840         } else {
 841             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 842                                        hc->poly_key_8[i], data[i]);
 843         }
 844     }
 845 }
 846
 847
 848 /* ---------------------------------------------------------------------- */
 849
 850
 851 /* The final step in UHASH is an inner-product hash. The poly hash
 852  * produces a result not neccesarily WORD_LEN bytes long. The inner-
 853  * product hash breaks the polyhash output into 16-bit chunks and
 854  * multiplies each with a 36 bit key.
 855  */
 856
 857 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
 858 {
 859     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
 860     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
 861     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
 862     t = t + ipkp[3] * (UINT64)(UINT16)(data);
 863
 864     return t;
 865 }
 866
 867 static UINT32 ip_reduce_p36(UINT64 t)
 868 {
 869 /* Divisionless modular reduction */
 870     UINT64 ret;
 871
 872     ret = (t & m36) + 5 * (t >> 36);
 873     if (ret >= p36)
 874         ret -= p36;
 875
 876     /* return least significant 32 bits */
 877     return (UINT32)(ret);
 878 }
 879
 880
 881 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
 882  * the polyhash stage is skipped and ip_short is applied directly to the
 883  * NH output.
 884  */
 885 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
 886 {
 887     UINT64 t;
 888     UINT64 *nhp = (UINT64 *)nh_res;
 889
 890     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
 891     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
 892 #if (UMAC_OUTPUT_LEN >= 8)
 893     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
 894     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
 895 #endif
 896 #if (UMAC_OUTPUT_LEN >= 12)
 897     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
 898     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
 899 #endif
 900 #if (UMAC_OUTPUT_LEN == 16)
 901     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
 902     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
 903 #endif
 904 }
 905
 906 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
 907  * the polyhash stage is not skipped and ip_long is applied to the
 908  * polyhash output.
 909  */
 910 static void ip_long(uhash_ctx_t ahc, u_char *res)
 911 {
 912     int i;
 913     UINT64 t;
 914
 915     for (i = 0; i < STREAMS; i++) {
 916         /* fix polyhash output not in Z_p64 */
 917         if (ahc->poly_accum[i] >= p64)
 918             ahc->poly_accum[i] -= p64;
 919         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
 920         STORE_UINT32_BIG((UINT32 *)res+i,
 921                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
 922     }
 923 }
 924
 925
 926 /* ---------------------------------------------------------------------- */
 927
 928 /* ---------------------------------------------------------------------- */
 929
 930 /* Reset uhash context for next hash session */
 931 static int uhash_reset(uhash_ctx_t pc)
 932 {
 933     nh_reset(&pc->hash);
 934     pc->msg_len = 0;
 935     pc->poly_accum[0] = 1;
 936 #if (UMAC_OUTPUT_LEN >= 8)
 937     pc->poly_accum[1] = 1;
 938 #endif
 939 #if (UMAC_OUTPUT_LEN >= 12)
 940     pc->poly_accum[2] = 1;
 941 #endif
 942 #if (UMAC_OUTPUT_LEN == 16)
 943     pc->poly_accum[3] = 1;
 944 #endif
 945     return 1;
 946 }
 947
 948 /* ---------------------------------------------------------------------- */
 949
 950 /* Given a pointer to the internal key needed by kdf() and a uhash context,
 951  * initialize the NH context and generate keys needed for poly and inner-
 952  * product hashing. All keys are endian adjusted in memory so that native
 953  * loads cause correct keys to be in registers during calculation.
 954  */
 955 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
 956 {
 957     int i;
 958     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
 959
 960     /* Zero the entire uhash context */
 961     memset(ahc, 0, sizeof(uhash_ctx));
 962
 963     /* Initialize the L1 hash */
 964     nh_init(&ahc->hash, prf_key);
 965
 966     /* Setup L2 hash variables */
 967     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
 968     for (i = 0; i < STREAMS; i++) {
 969         /* Fill keys from the buffer, skipping bytes in the buffer not
 970          * used by this implementation. Endian reverse the keys if on a
 971          * little-endian computer.
 972          */
 973         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
 974         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
 975         /* Mask the 64-bit keys to their special domain */
 976         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
 977         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
 978     }
 979
 980     /* Setup L3-1 hash variables */
 981     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
 982     for (i = 0; i < STREAMS; i++)
 983           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
 984                                                  4*sizeof(UINT64));
 985     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
 986                                                   sizeof(ahc->ip_keys));
 987     for (i = 0; i < STREAMS*4; i++)
 988         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
 989
 990     /* Setup L3-2 hash variables    */
 991     /* Fill buffer with index 4 key */
 992     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
 993     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
 994                          STREAMS * sizeof(UINT32));
 995 }
 996
 997 /* ---------------------------------------------------------------------- */
 998
 999 #if 0
1000 static uhash_ctx_t uhash_alloc(u_char key[])
1001 {
1002 /* Allocate memory and force to a 16-byte boundary. */
1003     uhash_ctx_t ctx;
1004     u_char bytes_to_add;
1005     aes_int_key prf_key;
1006
1007     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1008     if (ctx) {
1009         if (ALLOC_BOUNDARY) {
1010             bytes_to_add = ALLOC_BOUNDARY -
1011                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1012             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1013             *((u_char *)ctx - 1) = bytes_to_add;
1014         }
1015         aes_key_setup(key,prf_key);
1016         uhash_init(ctx, prf_key);
1017     }
1018     return (ctx);
1019 }
1020 #endif
1021
1022 /* ---------------------------------------------------------------------- */
1023
1024 #if 0
1025 static int uhash_free(uhash_ctx_t ctx)
1026 {
1027 /* Free memory allocated by uhash_alloc */
1028     u_char bytes_to_sub;
1029
1030     if (ctx) {
1031         if (ALLOC_BOUNDARY) {
1032             bytes_to_sub = *((u_char *)ctx - 1);
1033             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1034         }
1035         free(ctx);
1036     }
1037     return (1);
1038 }
1039 #endif
1040 /* ---------------------------------------------------------------------- */
1041
1042 static int uhash_update(uhash_ctx_t ctx, u_char *input, long len)
1043 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1044  * hash each one with NH, calling the polyhash on each NH output.
1045  */
1046 {
1047     UWORD bytes_hashed, bytes_remaining;
1048     UINT64 result_buf[STREAMS];
1049     UINT8 *nh_result = (UINT8 *)&result_buf;
1050
1051     if (ctx->msg_len + len <= L1_KEY_LEN) {
1052         nh_update(&ctx->hash, (UINT8 *)input, len);
1053         ctx->msg_len += len;
1054     } else {
1055
1056          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1057          if (ctx->msg_len == L1_KEY_LEN)
1058              bytes_hashed = L1_KEY_LEN;
1059
1060          if (bytes_hashed + len >= L1_KEY_LEN) {
1061
1062              /* If some bytes have been passed to the hash function      */
1063              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1064              /* bytes to complete the current nh_block.                  */
1065              if (bytes_hashed) {
1066                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1067                  nh_update(&ctx->hash, (UINT8 *)input, bytes_remaining);
1068                  nh_final(&ctx->hash, nh_result);
1069                  ctx->msg_len += bytes_remaining;
1070                  poly_hash(ctx,(UINT32 *)nh_result);
1071                  len -= bytes_remaining;
1072                  input += bytes_remaining;
1073              }
1074
1075              /* Hash directly from input stream if enough bytes */
1076              while (len >= L1_KEY_LEN) {
1077                  nh(&ctx->hash, (UINT8 *)input, L1_KEY_LEN,
1078                                    L1_KEY_LEN, nh_result);
1079                  ctx->msg_len += L1_KEY_LEN;
1080                  len -= L1_KEY_LEN;
1081                  input += L1_KEY_LEN;
1082                  poly_hash(ctx,(UINT32 *)nh_result);
1083              }
1084          }
1085
1086          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1087          if (len) {
1088              nh_update(&ctx->hash, (UINT8 *)input, len);
1089              ctx->msg_len += len;
1090          }
1091      }
1092
1093     return (1);
1094 }
1095
1096 /* ---------------------------------------------------------------------- */
1097
1098 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1099 /* Incorporate any pending data, pad, and generate tag */
1100 {
1101     UINT64 result_buf[STREAMS];
1102     UINT8 *nh_result = (UINT8 *)&result_buf;
1103
1104     if (ctx->msg_len > L1_KEY_LEN) {
1105         if (ctx->msg_len % L1_KEY_LEN) {
1106             nh_final(&ctx->hash, nh_result);
1107             poly_hash(ctx,(UINT32 *)nh_result);
1108         }
1109         ip_long(ctx, res);
1110     } else {
1111         nh_final(&ctx->hash, nh_result);
1112         ip_short(ctx,nh_result, res);
1113     }
1114     uhash_reset(ctx);
1115     return (1);
1116 }
1117
1118 /* ---------------------------------------------------------------------- */
1119
1120 #if 0
1121 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1122 /* assumes that msg is in a writable buffer of length divisible by */
1123 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1124 {
1125     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1126     UINT32 nh_len;
1127     int extra_zeroes_needed;
1128
1129     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1130      * the polyhash.
1131      */
1132     if (len <= L1_KEY_LEN) {
1133         if (len == 0)                  /* If zero length messages will not */
1134                 nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1135         else
1136                 nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1137         extra_zeroes_needed = nh_len - len;
1138         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1139         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1140         ip_short(ahc,nh_result, res);
1141     } else {
1142         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1143          * output to poly_hash().
1144          */
1145         do {
1146             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1147             poly_hash(ahc,(UINT32 *)nh_result);
1148             len -= L1_KEY_LEN;
1149             msg += L1_KEY_LEN;
1150         } while (len >= L1_KEY_LEN);
1151         if (len) {
1152             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1153             extra_zeroes_needed = nh_len - len;
1154             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1155             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1156             poly_hash(ahc,(UINT32 *)nh_result);
1157         }
1158
1159         ip_long(ahc, res);
1160     }
1161
1162     uhash_reset(ahc);
1163     return 1;
1164 }
1165 #endif
1166
1167 /* ---------------------------------------------------------------------- */
1168 /* ---------------------------------------------------------------------- */
1169 /* ----- Begin UMAC Section --------------------------------------------- */
1170 /* ---------------------------------------------------------------------- */
1171 /* ---------------------------------------------------------------------- */
1172
1173 /* The UMAC interface has two interfaces, an all-at-once interface where
1174  * the entire message to be authenticated is passed to UMAC in one buffer,
1175  * and a sequential interface where the message is presented a little at a
1176  * time. The all-at-once is more optimaized than the sequential version and
1177  * should be preferred when the sequential interface is not required.
1178  */
1179 struct umac_ctx {
1180     uhash_ctx hash;          /* Hash function for message compression    */
1181     pdf_ctx pdf;             /* PDF for hashed output                    */
1182     void *free_ptr;          /* Address to free this struct via          */
1183 } umac_ctx;
1184
1185 /* ---------------------------------------------------------------------- */
1186
1187 #if 0
1188 int umac_reset(struct umac_ctx *ctx)
1189 /* Reset the hash function to begin a new authentication.        */
1190 {
1191     uhash_reset(&ctx->hash);
1192     return (1);
1193 }
1194 #endif
1195
1196 /* ---------------------------------------------------------------------- */
1197
1198 int umac_delete(struct umac_ctx *ctx)
1199 /* Deallocate the ctx structure */
1200 {
1201     if (ctx) {
1202         if (ALLOC_BOUNDARY)
1203             ctx = (struct umac_ctx *)ctx->free_ptr;
1204         xfree(ctx);
1205     }
1206     return (1);
1207 }
1208
1209 /* ---------------------------------------------------------------------- */
1210
1211 struct umac_ctx *umac_new(u_char key[])
1212 /* Dynamically allocate a umac_ctx struct, initialize variables,
1213  * generate subkeys from key. Align to 16-byte boundary.
1214  */
1215 {
1216     struct umac_ctx *ctx, *octx;
1217     size_t bytes_to_add;
1218     aes_int_key prf_key;
1219
1220     octx = ctx = xmalloc(sizeof(*ctx) + ALLOC_BOUNDARY);
1221     if (ctx) {
1222         if (ALLOC_BOUNDARY) {
1223             bytes_to_add = ALLOC_BOUNDARY -
1224                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1225             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1226         }
1227         ctx->free_ptr = octx;
1228         aes_key_setup(key,prf_key);
1229         pdf_init(&ctx->pdf, prf_key);
1230         uhash_init(&ctx->hash, prf_key);
1231     }
1232
1233     return (ctx);
1234 }
1235
1236 /* ---------------------------------------------------------------------- */
1237
1238 int umac_final(struct umac_ctx *ctx, u_char tag[], u_char nonce[8])
1239 /* Incorporate any pending data, pad, and generate tag */
1240 {
1241     uhash_final(&ctx->hash, (u_char *)tag);
1242     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1243
1244     return (1);
1245 }
1246
1247 /* ---------------------------------------------------------------------- */
1248
1249 int umac_update(struct umac_ctx *ctx, u_char *input, long len)
1250 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1251 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1252 /* output buffer is full.                                                 */
1253 {
1254     uhash_update(&ctx->hash, input, len);
1255     return (1);
1256 }
1257
1258 /* ---------------------------------------------------------------------- */
1259
1260 #if 0
1261 int umac(struct umac_ctx *ctx, u_char *input,
1262          long len, u_char tag[],
1263          u_char nonce[8])
1264 /* All-in-one version simply calls umac_update() and umac_final().        */
1265 {
1266     uhash(&ctx->hash, input, len, (u_char *)tag);
1267     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1268
1269     return (1);
1270 }
1271 #endif
1272
1273 /* ---------------------------------------------------------------------- */
1274 /* ---------------------------------------------------------------------- */
1275 /* ----- End UMAC Section ----------------------------------------------- */
1276 /* ---------------------------------------------------------------------- */
1277 /* ---------------------------------------------------------------------- */