crypto/openssh-4/umac.c

   1 /* $OpenBSD: umac.c,v 1.1 2007/06/07 19:37:34 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 "umac.h"
  70 #include <string.h>
  71 #include <stdlib.h>
  72 #include <stddef.h>
  73
  74 /* ---------------------------------------------------------------------- */
  75 /* --- Primitive Data Types ---                                           */
  76 /* ---------------------------------------------------------------------- */
  77
  78 /* The following assumptions may need change on your system */
  79 typedef u_int8_t        UINT8;  /* 1 byte   */
  80 typedef u_int16_t       UINT16; /* 2 byte   */
  81 typedef u_int32_t       UINT32; /* 4 byte   */
  82 typedef u_int64_t       UINT64; /* 8 bytes  */
  83 typedef unsigned int    UWORD;  /* Register */
  84
  85 /* ---------------------------------------------------------------------- */
  86 /* --- Constants -------------------------------------------------------- */
  87 /* ---------------------------------------------------------------------- */
  88
  89 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
  90
  91 /* Message "words" are read from memory in an endian-specific manner.     */
  92 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
  93 /* be set true if the host computer is little-endian.                     */
  94
  95 #if BYTE_ORDER == LITTLE_ENDIAN
  96 #define __LITTLE_ENDIAN__ 1
  97 #else
  98 #define __LITTLE_ENDIAN__ 0
  99 #endif
 100
 101 /* ---------------------------------------------------------------------- */
 102 /* ---------------------------------------------------------------------- */
 103 /* ----- Architecture Specific ------------------------------------------ */
 104 /* ---------------------------------------------------------------------- */
 105 /* ---------------------------------------------------------------------- */
 106
 107
 108 /* ---------------------------------------------------------------------- */
 109 /* ---------------------------------------------------------------------- */
 110 /* ----- Primitive Routines --------------------------------------------- */
 111 /* ---------------------------------------------------------------------- */
 112 /* ---------------------------------------------------------------------- */
 113
 114
 115 /* ---------------------------------------------------------------------- */
 116 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
 117 /* ---------------------------------------------------------------------- */
 118
 119 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
 120
 121 /* ---------------------------------------------------------------------- */
 122 /* --- Endian Conversion --- Forcing assembly on some platforms           */
 123 /* ---------------------------------------------------------------------- */
 124
 125 #if HAVE_SWAP32
 126 #define LOAD_UINT32_REVERSED(p)         (swap32(*(UINT32 *)(p)))
 127 #define STORE_UINT32_REVERSED(p,v)      (*(UINT32 *)(p) = swap32(v))
 128 #else /* HAVE_SWAP32 */
 129
 130 static UINT32 LOAD_UINT32_REVERSED(void *ptr)
 131 {
 132     UINT32 temp = *(UINT32 *)ptr;
 133     temp = (temp >> 24) | ((temp & 0x00FF0000) >> 8 )
 134          | ((temp & 0x0000FF00) << 8 ) | (temp << 24);
 135     return (UINT32)temp;
 136 }
 137
 138 static void STORE_UINT32_REVERSED(void *ptr, UINT32 x)
 139 {
 140     UINT32 i = (UINT32)x;
 141     *(UINT32 *)ptr = (i >> 24) | ((i & 0x00FF0000) >> 8 )
 142                    | ((i & 0x0000FF00) << 8 ) | (i << 24);
 143 }
 144 #endif /* HAVE_SWAP32 */
 145
 146 /* The following definitions use the above reversal-primitives to do the right
 147  * thing on endian specific load and stores.
 148  */
 149
 150 #if (__LITTLE_ENDIAN__)
 151 #define LOAD_UINT32_LITTLE(ptr)     (*(UINT32 *)(ptr))
 152 #define STORE_UINT32_BIG(ptr,x)     STORE_UINT32_REVERSED(ptr,x)
 153 #else
 154 #define LOAD_UINT32_LITTLE(ptr)     LOAD_UINT32_REVERSED(ptr)
 155 #define STORE_UINT32_BIG(ptr,x)     (*(UINT32 *)(ptr) = (UINT32)(x))
 156 #endif
 157
 158 /* ---------------------------------------------------------------------- */
 159 /* ---------------------------------------------------------------------- */
 160 /* ----- Begin KDF & PDF Section ---------------------------------------- */
 161 /* ---------------------------------------------------------------------- */
 162 /* ---------------------------------------------------------------------- */
 163
 164 /* UMAC uses AES with 16 byte block and key lengths */
 165 #define AES_BLOCK_LEN  16
 166
 167 /* OpenSSL's AES */
 168 #include "openbsd-compat/openssl-compat.h"
 169 #ifndef USE_BUILTIN_RIJNDAEL
 170 # include <openssl/aes.h>
 171 #endif
 172 typedef AES_KEY aes_int_key[1];
 173 #define aes_encryption(in,out,int_key)                  \
 174   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
 175 #define aes_key_setup(key,int_key)                      \
 176   AES_set_encrypt_key((u_char *)(key),UMAC_KEY_LEN*8,int_key)
 177
 178 /* The user-supplied UMAC key is stretched using AES in a counter
 179  * mode to supply all random bits needed by UMAC. The kdf function takes
 180  * an AES internal key representation 'key' and writes a stream of
 181  * 'nbytes' bytes to the memory pointed at by 'buffer_ptr'. Each distinct
 182  * 'ndx' causes a distinct byte stream.
 183  */
 184 static void kdf(void *buffer_ptr, aes_int_key key, UINT8 ndx, int nbytes)
 185 {
 186     UINT8 in_buf[AES_BLOCK_LEN] = {0};
 187     UINT8 out_buf[AES_BLOCK_LEN];
 188     UINT8 *dst_buf = (UINT8 *)buffer_ptr;
 189     int i;
 190
 191     /* Setup the initial value */
 192     in_buf[AES_BLOCK_LEN-9] = ndx;
 193     in_buf[AES_BLOCK_LEN-1] = i = 1;
 194
 195     while (nbytes >= AES_BLOCK_LEN) {
 196         aes_encryption(in_buf, out_buf, key);
 197         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
 198         in_buf[AES_BLOCK_LEN-1] = ++i;
 199         nbytes -= AES_BLOCK_LEN;
 200         dst_buf += AES_BLOCK_LEN;
 201     }
 202     if (nbytes) {
 203         aes_encryption(in_buf, out_buf, key);
 204         memcpy(dst_buf,out_buf,nbytes);
 205     }
 206 }
 207
 208 /* The final UHASH result is XOR'd with the output of a pseudorandom
 209  * function. Here, we use AES to generate random output and
 210  * xor the appropriate bytes depending on the last bits of nonce.
 211  * This scheme is optimized for sequential, increasing big-endian nonces.
 212  */
 213
 214 typedef struct {
 215     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
 216     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
 217     aes_int_key prf_key;         /* Expanded AES key for PDF          */
 218 } pdf_ctx;
 219
 220 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
 221 {
 222     UINT8 buf[UMAC_KEY_LEN];
 223
 224     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
 225     aes_key_setup(buf, pc->prf_key);
 226
 227     /* Initialize pdf and cache */
 228     memset(pc->nonce, 0, sizeof(pc->nonce));
 229     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 230 }
 231
 232 static void pdf_gen_xor(pdf_ctx *pc, UINT8 nonce[8], UINT8 buf[8])
 233 {
 234     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
 235      * of the AES output. If last time around we returned the ndx-1st
 236      * element, then we may have the result in the cache already.
 237      */
 238
 239 #if (UMAC_OUTPUT_LEN == 4)
 240 #define LOW_BIT_MASK 3
 241 #elif (UMAC_OUTPUT_LEN == 8)
 242 #define LOW_BIT_MASK 1
 243 #elif (UMAC_OUTPUT_LEN > 8)
 244 #define LOW_BIT_MASK 0
 245 #endif
 246
 247     UINT8 tmp_nonce_lo[4];
 248 #if LOW_BIT_MASK != 0
 249     int ndx = nonce[7] & LOW_BIT_MASK;
 250 #endif
 251     *(UINT32 *)tmp_nonce_lo = ((UINT32 *)nonce)[1];
 252     tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
 253
 254     if ( (((UINT32 *)tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
 255          (((UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
 256     {
 257         ((UINT32 *)pc->nonce)[0] = ((UINT32 *)nonce)[0];
 258         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)tmp_nonce_lo)[0];
 259         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 260     }
 261
 262 #if (UMAC_OUTPUT_LEN == 4)
 263     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
 264 #elif (UMAC_OUTPUT_LEN == 8)
 265     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
 266 #elif (UMAC_OUTPUT_LEN == 12)
 267     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 268     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
 269 #elif (UMAC_OUTPUT_LEN == 16)
 270     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 271     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
 272 #endif
 273 }
 274
 275 /* ---------------------------------------------------------------------- */
 276 /* ---------------------------------------------------------------------- */
 277 /* ----- Begin NH Hash Section ------------------------------------------ */
 278 /* ---------------------------------------------------------------------- */
 279 /* ---------------------------------------------------------------------- */
 280
 281 /* The NH-based hash functions used in UMAC are described in the UMAC paper
 282  * and specification, both of which can be found at the UMAC website.
 283  * The interface to this implementation has two
 284  * versions, one expects the entire message being hashed to be passed
 285  * in a single buffer and returns the hash result immediately. The second
 286  * allows the message to be passed in a sequence of buffers. In the
 287  * muliple-buffer interface, the client calls the routine nh_update() as
 288  * many times as necessary. When there is no more data to be fed to the
 289  * hash, the client calls nh_final() which calculates the hash output.
 290  * Before beginning another hash calculation the nh_reset() routine
 291  * must be called. The single-buffer routine, nh(), is equivalent to
 292  * the sequence of calls nh_update() and nh_final(); however it is
 293  * optimized and should be prefered whenever the multiple-buffer interface
 294  * is not necessary. When using either interface, it is the client's
 295  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
 296  *
 297  * The routine nh_init() initializes the nh_ctx data structure and
 298  * must be called once, before any other PDF routine.
 299  */
 300
 301  /* The "nh_aux" routines do the actual NH hashing work. They
 302   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
 303   * produce output for all STREAMS NH iterations in one call,
 304   * allowing the parallel implementation of the streams.
 305   */
 306
 307 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
 308 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
 309 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
 310 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
 311 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
 312 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
 313
 314 typedef struct {
 315     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
 316     UINT8  data   [HASH_BUF_BYTES];    /* Incomming data buffer           */
 317     int next_data_empty;    /* Bookeeping variable for data buffer.       */
 318     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
 319     UINT64 state[STREAMS];               /* on-line state     */
 320 } nh_ctx;
 321
 322
 323 #if (UMAC_OUTPUT_LEN == 4)
 324
 325 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 326 /* NH hashing primitive. Previous (partial) hash result is loaded and
 327 * then stored via hp pointer. The length of the data pointed at by "dp",
 328 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
 329 * is expected to be endian compensated in memory at key setup.
 330 */
 331 {
 332     UINT64 h;
 333     UWORD c = dlen / 32;
 334     UINT32 *k = (UINT32 *)kp;
 335     UINT32 *d = (UINT32 *)dp;
 336     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 337     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
 338
 339     h = *((UINT64 *)hp);
 340     do {
 341         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 342         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 343         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 344         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 345         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 346         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 347         h += MUL64((k0 + d0), (k4 + d4));
 348         h += MUL64((k1 + d1), (k5 + d5));
 349         h += MUL64((k2 + d2), (k6 + d6));
 350         h += MUL64((k3 + d3), (k7 + d7));
 351
 352         d += 8;
 353         k += 8;
 354     } while (--c);
 355   *((UINT64 *)hp) = h;
 356 }
 357
 358 #elif (UMAC_OUTPUT_LEN == 8)
 359
 360 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 361 /* Same as previous nh_aux, but two streams are handled in one pass,
 362  * reading and writing 16 bytes of hash-state per call.
 363  */
 364 {
 365   UINT64 h1,h2;
 366   UWORD c = dlen / 32;
 367   UINT32 *k = (UINT32 *)kp;
 368   UINT32 *d = (UINT32 *)dp;
 369   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 370   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 371         k8,k9,k10,k11;
 372
 373   h1 = *((UINT64 *)hp);
 374   h2 = *((UINT64 *)hp + 1);
 375   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 376   do {
 377     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 378     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 379     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 380     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 381     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 382     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 383
 384     h1 += MUL64((k0 + d0), (k4 + d4));
 385     h2 += MUL64((k4 + d0), (k8 + d4));
 386
 387     h1 += MUL64((k1 + d1), (k5 + d5));
 388     h2 += MUL64((k5 + d1), (k9 + d5));
 389
 390     h1 += MUL64((k2 + d2), (k6 + d6));
 391     h2 += MUL64((k6 + d2), (k10 + d6));
 392
 393     h1 += MUL64((k3 + d3), (k7 + d7));
 394     h2 += MUL64((k7 + d3), (k11 + d7));
 395
 396     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 397
 398     d += 8;
 399     k += 8;
 400   } while (--c);
 401   ((UINT64 *)hp)[0] = h1;
 402   ((UINT64 *)hp)[1] = h2;
 403 }
 404
 405 #elif (UMAC_OUTPUT_LEN == 12)
 406
 407 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 408 /* Same as previous nh_aux, but two streams are handled in one pass,
 409  * reading and writing 24 bytes of hash-state per call.
 410 */
 411 {
 412     UINT64 h1,h2,h3;
 413     UWORD c = dlen / 32;
 414     UINT32 *k = (UINT32 *)kp;
 415     UINT32 *d = (UINT32 *)dp;
 416     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 417     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 418         k8,k9,k10,k11,k12,k13,k14,k15;
 419
 420     h1 = *((UINT64 *)hp);
 421     h2 = *((UINT64 *)hp + 1);
 422     h3 = *((UINT64 *)hp + 2);
 423     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 424     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 425     do {
 426         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 427         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 428         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 429         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 430         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 431         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 432
 433         h1 += MUL64((k0 + d0), (k4 + d4));
 434         h2 += MUL64((k4 + d0), (k8 + d4));
 435         h3 += MUL64((k8 + d0), (k12 + d4));
 436
 437         h1 += MUL64((k1 + d1), (k5 + d5));
 438         h2 += MUL64((k5 + d1), (k9 + d5));
 439         h3 += MUL64((k9 + d1), (k13 + d5));
 440
 441         h1 += MUL64((k2 + d2), (k6 + d6));
 442         h2 += MUL64((k6 + d2), (k10 + d6));
 443         h3 += MUL64((k10 + d2), (k14 + d6));
 444
 445         h1 += MUL64((k3 + d3), (k7 + d7));
 446         h2 += MUL64((k7 + d3), (k11 + d7));
 447         h3 += MUL64((k11 + d3), (k15 + d7));
 448
 449         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 450         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 451
 452         d += 8;
 453         k += 8;
 454     } while (--c);
 455     ((UINT64 *)hp)[0] = h1;
 456     ((UINT64 *)hp)[1] = h2;
 457     ((UINT64 *)hp)[2] = h3;
 458 }
 459
 460 #elif (UMAC_OUTPUT_LEN == 16)
 461
 462 static void nh_aux(void *kp, void *dp, void *hp, UINT32 dlen)
 463 /* Same as previous nh_aux, but two streams are handled in one pass,
 464  * reading and writing 24 bytes of hash-state per call.
 465 */
 466 {
 467     UINT64 h1,h2,h3,h4;
 468     UWORD c = dlen / 32;
 469     UINT32 *k = (UINT32 *)kp;
 470     UINT32 *d = (UINT32 *)dp;
 471     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 472     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 473         k8,k9,k10,k11,k12,k13,k14,k15,
 474         k16,k17,k18,k19;
 475
 476     h1 = *((UINT64 *)hp);
 477     h2 = *((UINT64 *)hp + 1);
 478     h3 = *((UINT64 *)hp + 2);
 479     h4 = *((UINT64 *)hp + 3);
 480     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 481     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 482     do {
 483         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 484         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 485         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 486         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 487         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 488         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 489         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
 490
 491         h1 += MUL64((k0 + d0), (k4 + d4));
 492         h2 += MUL64((k4 + d0), (k8 + d4));
 493         h3 += MUL64((k8 + d0), (k12 + d4));
 494         h4 += MUL64((k12 + d0), (k16 + d4));
 495
 496         h1 += MUL64((k1 + d1), (k5 + d5));
 497         h2 += MUL64((k5 + d1), (k9 + d5));
 498         h3 += MUL64((k9 + d1), (k13 + d5));
 499         h4 += MUL64((k13 + d1), (k17 + d5));
 500
 501         h1 += MUL64((k2 + d2), (k6 + d6));
 502         h2 += MUL64((k6 + d2), (k10 + d6));
 503         h3 += MUL64((k10 + d2), (k14 + d6));
 504         h4 += MUL64((k14 + d2), (k18 + d6));
 505
 506         h1 += MUL64((k3 + d3), (k7 + d7));
 507         h2 += MUL64((k7 + d3), (k11 + d7));
 508         h3 += MUL64((k11 + d3), (k15 + d7));
 509         h4 += MUL64((k15 + d3), (k19 + d7));
 510
 511         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 512         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 513         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
 514
 515         d += 8;
 516         k += 8;
 517     } while (--c);
 518     ((UINT64 *)hp)[0] = h1;
 519     ((UINT64 *)hp)[1] = h2;
 520     ((UINT64 *)hp)[2] = h3;
 521     ((UINT64 *)hp)[3] = h4;
 522 }
 523
 524 /* ---------------------------------------------------------------------- */
 525 #endif  /* UMAC_OUTPUT_LENGTH */
 526 /* ---------------------------------------------------------------------- */
 527
 528
 529 /* ---------------------------------------------------------------------- */
 530
 531 static void nh_transform(nh_ctx *hc, UINT8 *buf, UINT32 nbytes)
 532 /* This function is a wrapper for the primitive NH hash functions. It takes
 533  * as argument "hc" the current hash context and a buffer which must be a
 534  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
 535  * appropriately according to how much message has been hashed already.
 536  */
 537 {
 538     UINT8 *key;
 539
 540     key = hc->nh_key + hc->bytes_hashed;
 541     nh_aux(key, buf, hc->state, nbytes);
 542 }
 543
 544 /* ---------------------------------------------------------------------- */
 545
 546 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
 547 /* We endian convert the keys on little-endian computers to               */
 548 /* compensate for the lack of big-endian memory reads during hashing.     */
 549 {
 550     UWORD iters = num_bytes / bpw;
 551     if (bpw == 4) {
 552         UINT32 *p = (UINT32 *)buf;
 553         do {
 554             *p = LOAD_UINT32_REVERSED(p);
 555             p++;
 556         } while (--iters);
 557     } else if (bpw == 8) {
 558         UINT32 *p = (UINT32 *)buf;
 559         UINT32 t;
 560         do {
 561             t = LOAD_UINT32_REVERSED(p+1);
 562             p[1] = LOAD_UINT32_REVERSED(p);
 563             p[0] = t;
 564             p += 2;
 565         } while (--iters);
 566     }
 567 }
 568 #if (__LITTLE_ENDIAN__)
 569 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
 570 #else
 571 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
 572 #endif
 573
 574 /* ---------------------------------------------------------------------- */
 575
 576 static void nh_reset(nh_ctx *hc)
 577 /* Reset nh_ctx to ready for hashing of new data */
 578 {
 579     hc->bytes_hashed = 0;
 580     hc->next_data_empty = 0;
 581     hc->state[0] = 0;
 582 #if (UMAC_OUTPUT_LEN >= 8)
 583     hc->state[1] = 0;
 584 #endif
 585 #if (UMAC_OUTPUT_LEN >= 12)
 586     hc->state[2] = 0;
 587 #endif
 588 #if (UMAC_OUTPUT_LEN == 16)
 589     hc->state[3] = 0;
 590 #endif
 591
 592 }
 593
 594 /* ---------------------------------------------------------------------- */
 595
 596 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
 597 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
 598 {
 599     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
 600     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
 601     nh_reset(hc);
 602 }
 603
 604 /* ---------------------------------------------------------------------- */
 605
 606 static void nh_update(nh_ctx *hc, UINT8 *buf, UINT32 nbytes)
 607 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
 608 /* even multiple of HASH_BUF_BYTES.                                       */
 609 {
 610     UINT32 i,j;
 611
 612     j = hc->next_data_empty;
 613     if ((j + nbytes) >= HASH_BUF_BYTES) {
 614         if (j) {
 615             i = HASH_BUF_BYTES - j;
 616             memcpy(hc->data+j, buf, i);
 617             nh_transform(hc,hc->data,HASH_BUF_BYTES);
 618             nbytes -= i;
 619             buf += i;
 620             hc->bytes_hashed += HASH_BUF_BYTES;
 621         }
 622         if (nbytes >= HASH_BUF_BYTES) {
 623             i = nbytes & ~(HASH_BUF_BYTES - 1);
 624             nh_transform(hc, buf, i);
 625             nbytes -= i;
 626             buf += i;
 627             hc->bytes_hashed += i;
 628         }
 629         j = 0;
 630     }
 631     memcpy(hc->data + j, buf, nbytes);
 632     hc->next_data_empty = j + nbytes;
 633 }
 634
 635 /* ---------------------------------------------------------------------- */
 636
 637 static void zero_pad(UINT8 *p, int nbytes)
 638 {
 639 /* Write "nbytes" of zeroes, beginning at "p" */
 640     if (nbytes >= (int)sizeof(UWORD)) {
 641         while ((ptrdiff_t)p % sizeof(UWORD)) {
 642             *p = 0;
 643             nbytes--;
 644             p++;
 645         }
 646         while (nbytes >= (int)sizeof(UWORD)) {
 647             *(UWORD *)p = 0;
 648             nbytes -= sizeof(UWORD);
 649             p += sizeof(UWORD);
 650         }
 651     }
 652     while (nbytes) {
 653         *p = 0;
 654         nbytes--;
 655         p++;
 656     }
 657 }
 658
 659 /* ---------------------------------------------------------------------- */
 660
 661 static void nh_final(nh_ctx *hc, UINT8 *result)
 662 /* After passing some number of data buffers to nh_update() for integration
 663  * into an NH context, nh_final is called to produce a hash result. If any
 664  * bytes are in the buffer hc->data, incorporate them into the
 665  * NH context. Finally, add into the NH accumulation "state" the total number
 666  * of bits hashed. The resulting numbers are written to the buffer "result".
 667  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
 668  */
 669 {
 670     int nh_len, nbits;
 671
 672     if (hc->next_data_empty != 0) {
 673         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
 674                                                 ~(L1_PAD_BOUNDARY - 1));
 675         zero_pad(hc->data + hc->next_data_empty,
 676                                           nh_len - hc->next_data_empty);
 677         nh_transform(hc, hc->data, nh_len);
 678         hc->bytes_hashed += hc->next_data_empty;
 679     } else if (hc->bytes_hashed == 0) {
 680         nh_len = L1_PAD_BOUNDARY;
 681         zero_pad(hc->data, L1_PAD_BOUNDARY);
 682         nh_transform(hc, hc->data, nh_len);
 683     }
 684
 685     nbits = (hc->bytes_hashed << 3);
 686     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
 687 #if (UMAC_OUTPUT_LEN >= 8)
 688     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
 689 #endif
 690 #if (UMAC_OUTPUT_LEN >= 12)
 691     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
 692 #endif
 693 #if (UMAC_OUTPUT_LEN == 16)
 694     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
 695 #endif
 696     nh_reset(hc);
 697 }
 698
 699 /* ---------------------------------------------------------------------- */
 700
 701 static void nh(nh_ctx *hc, UINT8 *buf, UINT32 padded_len,
 702                UINT32 unpadded_len, UINT8 *result)
 703 /* All-in-one nh_update() and nh_final() equivalent.
 704  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
 705  * well aligned
 706  */
 707 {
 708     UINT32 nbits;
 709
 710     /* Initialize the hash state */
 711     nbits = (unpadded_len << 3);
 712
 713     ((UINT64 *)result)[0] = nbits;
 714 #if (UMAC_OUTPUT_LEN >= 8)
 715     ((UINT64 *)result)[1] = nbits;
 716 #endif
 717 #if (UMAC_OUTPUT_LEN >= 12)
 718     ((UINT64 *)result)[2] = nbits;
 719 #endif
 720 #if (UMAC_OUTPUT_LEN == 16)
 721     ((UINT64 *)result)[3] = nbits;
 722 #endif
 723
 724     nh_aux(hc->nh_key, buf, result, padded_len);
 725 }
 726
 727 /* ---------------------------------------------------------------------- */
 728 /* ---------------------------------------------------------------------- */
 729 /* ----- Begin UHASH Section -------------------------------------------- */
 730 /* ---------------------------------------------------------------------- */
 731 /* ---------------------------------------------------------------------- */
 732
 733 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
 734  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
 735  * unless the initial data to be hashed is short. After the polynomial-
 736  * layer, an inner-product hash is used to produce the final UHASH output.
 737  *
 738  * UHASH provides two interfaces, one all-at-once and another where data
 739  * buffers are presented sequentially. In the sequential interface, the
 740  * UHASH client calls the routine uhash_update() as many times as necessary.
 741  * When there is no more data to be fed to UHASH, the client calls
 742  * uhash_final() which
 743  * calculates the UHASH output. Before beginning another UHASH calculation
 744  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
 745  * uhash(), is equivalent to the sequence of calls uhash_update() and
 746  * uhash_final(); however it is optimized and should be
 747  * used whenever the sequential interface is not necessary.
 748  *
 749  * The routine uhash_init() initializes the uhash_ctx data structure and
 750  * must be called once, before any other UHASH routine.
 751  */
 752
 753 /* ---------------------------------------------------------------------- */
 754 /* ----- Constants and uhash_ctx ---------------------------------------- */
 755 /* ---------------------------------------------------------------------- */
 756
 757 /* ---------------------------------------------------------------------- */
 758 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
 759 /* ---------------------------------------------------------------------- */
 760
 761 /* Primes and masks */
 762 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
 763 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
 764 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
 765
 766
 767 /* ---------------------------------------------------------------------- */
 768
 769 typedef struct uhash_ctx {
 770     nh_ctx hash;                          /* Hash context for L1 NH hash  */
 771     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
 772     UINT64 poly_accum[STREAMS];           /* poly hash result             */
 773     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
 774     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
 775     UINT32 msg_len;                       /* Total length of data passed  */
 776                                           /* to uhash */
 777 } uhash_ctx;
 778 typedef struct uhash_ctx *uhash_ctx_t;
 779
 780 /* ---------------------------------------------------------------------- */
 781
 782
 783 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
 784  * word at a time. As described in the specification, poly32 and poly64
 785  * require keys from special domains. The following implementations exploit
 786  * the special domains to avoid overflow. The results are not guaranteed to
 787  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
 788  * patches any errant values.
 789  */
 790
 791 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
 792 {
 793     UINT32 key_hi = (UINT32)(key >> 32),
 794            key_lo = (UINT32)key,
 795            cur_hi = (UINT32)(cur >> 32),
 796            cur_lo = (UINT32)cur,
 797            x_lo,
 798            x_hi;
 799     UINT64 X,T,res;
 800
 801     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
 802     x_lo = (UINT32)X;
 803     x_hi = (UINT32)(X >> 32);
 804
 805     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
 806
 807     T = ((UINT64)x_lo << 32);
 808     res += T;
 809     if (res < T)
 810         res += 59;
 811
 812     res += data;
 813     if (res < data)
 814         res += 59;
 815
 816     return res;
 817 }
 818
 819
 820 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
 821  * implementation does not handle all ramp levels. Because we don't handle
 822  * the ramp up to p128 modulus in this implementation, we are limited to
 823  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
 824  * bytes input to UMAC per tag, ie. 16MB).
 825  */
 826 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
 827 {
 828     int i;
 829     UINT64 *data=(UINT64*)data_in;
 830
 831     for (i = 0; i < STREAMS; i++) {
 832         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
 833             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 834                                        hc->poly_key_8[i], p64 - 1);
 835             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 836                                        hc->poly_key_8[i], (data[i] - 59));
 837         } else {
 838             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 839                                        hc->poly_key_8[i], data[i]);
 840         }
 841     }
 842 }
 843
 844
 845 /* ---------------------------------------------------------------------- */
 846
 847
 848 /* The final step in UHASH is an inner-product hash. The poly hash
 849  * produces a result not neccesarily WORD_LEN bytes long. The inner-
 850  * product hash breaks the polyhash output into 16-bit chunks and
 851  * multiplies each with a 36 bit key.
 852  */
 853
 854 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
 855 {
 856     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
 857     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
 858     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
 859     t = t + ipkp[3] * (UINT64)(UINT16)(data);
 860
 861     return t;
 862 }
 863
 864 static UINT32 ip_reduce_p36(UINT64 t)
 865 {
 866 /* Divisionless modular reduction */
 867     UINT64 ret;
 868
 869     ret = (t & m36) + 5 * (t >> 36);
 870     if (ret >= p36)
 871         ret -= p36;
 872
 873     /* return least significant 32 bits */
 874     return (UINT32)(ret);
 875 }
 876
 877
 878 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
 879  * the polyhash stage is skipped and ip_short is applied directly to the
 880  * NH output.
 881  */
 882 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
 883 {
 884     UINT64 t;
 885     UINT64 *nhp = (UINT64 *)nh_res;
 886
 887     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
 888     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
 889 #if (UMAC_OUTPUT_LEN >= 8)
 890     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
 891     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
 892 #endif
 893 #if (UMAC_OUTPUT_LEN >= 12)
 894     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
 895     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
 896 #endif
 897 #if (UMAC_OUTPUT_LEN == 16)
 898     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
 899     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
 900 #endif
 901 }
 902
 903 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
 904  * the polyhash stage is not skipped and ip_long is applied to the
 905  * polyhash output.
 906  */
 907 static void ip_long(uhash_ctx_t ahc, u_char *res)
 908 {
 909     int i;
 910     UINT64 t;
 911
 912     for (i = 0; i < STREAMS; i++) {
 913         /* fix polyhash output not in Z_p64 */
 914         if (ahc->poly_accum[i] >= p64)
 915             ahc->poly_accum[i] -= p64;
 916         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
 917         STORE_UINT32_BIG((UINT32 *)res+i,
 918                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
 919     }
 920 }
 921
 922
 923 /* ---------------------------------------------------------------------- */
 924
 925 /* ---------------------------------------------------------------------- */
 926
 927 /* Reset uhash context for next hash session */
 928 static int uhash_reset(uhash_ctx_t pc)
 929 {
 930     nh_reset(&pc->hash);
 931     pc->msg_len = 0;
 932     pc->poly_accum[0] = 1;
 933 #if (UMAC_OUTPUT_LEN >= 8)
 934     pc->poly_accum[1] = 1;
 935 #endif
 936 #if (UMAC_OUTPUT_LEN >= 12)
 937     pc->poly_accum[2] = 1;
 938 #endif
 939 #if (UMAC_OUTPUT_LEN == 16)
 940     pc->poly_accum[3] = 1;
 941 #endif
 942     return 1;
 943 }
 944
 945 /* ---------------------------------------------------------------------- */
 946
 947 /* Given a pointer to the internal key needed by kdf() and a uhash context,
 948  * initialize the NH context and generate keys needed for poly and inner-
 949  * product hashing. All keys are endian adjusted in memory so that native
 950  * loads cause correct keys to be in registers during calculation.
 951  */
 952 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
 953 {
 954     int i;
 955     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
 956
 957     /* Zero the entire uhash context */
 958     memset(ahc, 0, sizeof(uhash_ctx));
 959
 960     /* Initialize the L1 hash */
 961     nh_init(&ahc->hash, prf_key);
 962
 963     /* Setup L2 hash variables */
 964     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
 965     for (i = 0; i < STREAMS; i++) {
 966         /* Fill keys from the buffer, skipping bytes in the buffer not
 967          * used by this implementation. Endian reverse the keys if on a
 968          * little-endian computer.
 969          */
 970         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
 971         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
 972         /* Mask the 64-bit keys to their special domain */
 973         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
 974         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
 975     }
 976
 977     /* Setup L3-1 hash variables */
 978     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
 979     for (i = 0; i < STREAMS; i++)
 980           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
 981                                                  4*sizeof(UINT64));
 982     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
 983                                                   sizeof(ahc->ip_keys));
 984     for (i = 0; i < STREAMS*4; i++)
 985         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
 986
 987     /* Setup L3-2 hash variables    */
 988     /* Fill buffer with index 4 key */
 989     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
 990     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
 991                          STREAMS * sizeof(UINT32));
 992 }
 993
 994 /* ---------------------------------------------------------------------- */
 995
 996 #if 0
 997 static uhash_ctx_t uhash_alloc(u_char key[])
 998 {
 999 /* Allocate memory and force to a 16-byte boundary. */
1000     uhash_ctx_t ctx;
1001     u_char bytes_to_add;
1002     aes_int_key prf_key;
1003
1004     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1005     if (ctx) {
1006         if (ALLOC_BOUNDARY) {
1007             bytes_to_add = ALLOC_BOUNDARY -
1008                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1009             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1010             *((u_char *)ctx - 1) = bytes_to_add;
1011         }
1012         aes_key_setup(key,prf_key);
1013         uhash_init(ctx, prf_key);
1014     }
1015     return (ctx);
1016 }
1017 #endif
1018
1019 /* ---------------------------------------------------------------------- */
1020
1021 #if 0
1022 static int uhash_free(uhash_ctx_t ctx)
1023 {
1024 /* Free memory allocated by uhash_alloc */
1025     u_char bytes_to_sub;
1026
1027     if (ctx) {
1028         if (ALLOC_BOUNDARY) {
1029             bytes_to_sub = *((u_char *)ctx - 1);
1030             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1031         }
1032         free(ctx);
1033     }
1034     return (1);
1035 }
1036 #endif
1037 /* ---------------------------------------------------------------------- */
1038
1039 static int uhash_update(uhash_ctx_t ctx, u_char *input, long len)
1040 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1041  * hash each one with NH, calling the polyhash on each NH output.
1042  */
1043 {
1044     UWORD bytes_hashed, bytes_remaining;
1045     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1046
1047     if (ctx->msg_len + len <= L1_KEY_LEN) {
1048         nh_update(&ctx->hash, (UINT8 *)input, len);
1049         ctx->msg_len += len;
1050     } else {
1051
1052          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1053          if (ctx->msg_len == L1_KEY_LEN)
1054              bytes_hashed = L1_KEY_LEN;
1055
1056          if (bytes_hashed + len >= L1_KEY_LEN) {
1057
1058              /* If some bytes have been passed to the hash function      */
1059              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1060              /* bytes to complete the current nh_block.                  */
1061              if (bytes_hashed) {
1062                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1063                  nh_update(&ctx->hash, (UINT8 *)input, bytes_remaining);
1064                  nh_final(&ctx->hash, nh_result);
1065                  ctx->msg_len += bytes_remaining;
1066                  poly_hash(ctx,(UINT32 *)nh_result);
1067                  len -= bytes_remaining;
1068                  input += bytes_remaining;
1069              }
1070
1071              /* Hash directly from input stream if enough bytes */
1072              while (len >= L1_KEY_LEN) {
1073                  nh(&ctx->hash, (UINT8 *)input, L1_KEY_LEN,
1074                                    L1_KEY_LEN, nh_result);
1075                  ctx->msg_len += L1_KEY_LEN;
1076                  len -= L1_KEY_LEN;
1077                  input += L1_KEY_LEN;
1078                  poly_hash(ctx,(UINT32 *)nh_result);
1079              }
1080          }
1081
1082          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1083          if (len) {
1084              nh_update(&ctx->hash, (UINT8 *)input, len);
1085              ctx->msg_len += len;
1086          }
1087      }
1088
1089     return (1);
1090 }
1091
1092 /* ---------------------------------------------------------------------- */
1093
1094 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1095 /* Incorporate any pending data, pad, and generate tag */
1096 {
1097     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1098
1099     if (ctx->msg_len > L1_KEY_LEN) {
1100         if (ctx->msg_len % L1_KEY_LEN) {
1101             nh_final(&ctx->hash, nh_result);
1102             poly_hash(ctx,(UINT32 *)nh_result);
1103         }
1104         ip_long(ctx, res);
1105     } else {
1106         nh_final(&ctx->hash, nh_result);
1107         ip_short(ctx,nh_result, res);
1108     }
1109     uhash_reset(ctx);
1110     return (1);
1111 }
1112
1113 /* ---------------------------------------------------------------------- */
1114
1115 #if 0
1116 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1117 /* assumes that msg is in a writable buffer of length divisible by */
1118 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1119 {
1120     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1121     UINT32 nh_len;
1122     int extra_zeroes_needed;
1123
1124     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1125      * the polyhash.
1126      */
1127     if (len <= L1_KEY_LEN) {
1128         if (len == 0)                  /* If zero length messages will not */
1129                 nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1130         else
1131                 nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1132         extra_zeroes_needed = nh_len - len;
1133         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1134         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1135         ip_short(ahc,nh_result, res);
1136     } else {
1137         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1138          * output to poly_hash().
1139          */
1140         do {
1141             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1142             poly_hash(ahc,(UINT32 *)nh_result);
1143             len -= L1_KEY_LEN;
1144             msg += L1_KEY_LEN;
1145         } while (len >= L1_KEY_LEN);
1146         if (len) {
1147             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1148             extra_zeroes_needed = nh_len - len;
1149             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1150             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1151             poly_hash(ahc,(UINT32 *)nh_result);
1152         }
1153
1154         ip_long(ahc, res);
1155     }
1156
1157     uhash_reset(ahc);
1158     return 1;
1159 }
1160 #endif
1161
1162 /* ---------------------------------------------------------------------- */
1163 /* ---------------------------------------------------------------------- */
1164 /* ----- Begin UMAC Section --------------------------------------------- */
1165 /* ---------------------------------------------------------------------- */
1166 /* ---------------------------------------------------------------------- */
1167
1168 /* The UMAC interface has two interfaces, an all-at-once interface where
1169  * the entire message to be authenticated is passed to UMAC in one buffer,
1170  * and a sequential interface where the message is presented a little at a
1171  * time. The all-at-once is more optimaized than the sequential version and
1172  * should be preferred when the sequential interface is not required.
1173  */
1174 struct umac_ctx {
1175     uhash_ctx hash;          /* Hash function for message compression    */
1176     pdf_ctx pdf;             /* PDF for hashed output                    */
1177     void *free_ptr;          /* Address to free this struct via          */
1178 } umac_ctx;
1179
1180 /* ---------------------------------------------------------------------- */
1181
1182 #if 0
1183 int umac_reset(struct umac_ctx *ctx)
1184 /* Reset the hash function to begin a new authentication.        */
1185 {
1186     uhash_reset(&ctx->hash);
1187     return (1);
1188 }
1189 #endif
1190
1191 /* ---------------------------------------------------------------------- */
1192
1193 int umac_delete(struct umac_ctx *ctx)
1194 /* Deallocate the ctx structure */
1195 {
1196     if (ctx) {
1197         if (ALLOC_BOUNDARY)
1198             ctx = (struct umac_ctx *)ctx->free_ptr;
1199         free(ctx);
1200     }
1201     return (1);
1202 }
1203
1204 /* ---------------------------------------------------------------------- */
1205
1206 struct umac_ctx *umac_new(u_char key[])
1207 /* Dynamically allocate a umac_ctx struct, initialize variables,
1208  * generate subkeys from key. Align to 16-byte boundary.
1209  */
1210 {
1211     struct umac_ctx *ctx, *octx;
1212     size_t bytes_to_add;
1213     aes_int_key prf_key;
1214
1215     octx = ctx = malloc(sizeof(*ctx) + ALLOC_BOUNDARY);
1216     if (ctx) {
1217         if (ALLOC_BOUNDARY) {
1218             bytes_to_add = ALLOC_BOUNDARY -
1219                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1220             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1221         }
1222         ctx->free_ptr = octx;
1223         aes_key_setup(key,prf_key);
1224         pdf_init(&ctx->pdf, prf_key);
1225         uhash_init(&ctx->hash, prf_key);
1226     }
1227
1228     return (ctx);
1229 }
1230
1231 /* ---------------------------------------------------------------------- */
1232
1233 int umac_final(struct umac_ctx *ctx, u_char tag[], u_char nonce[8])
1234 /* Incorporate any pending data, pad, and generate tag */
1235 {
1236     uhash_final(&ctx->hash, (u_char *)tag);
1237     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1238
1239     return (1);
1240 }
1241
1242 /* ---------------------------------------------------------------------- */
1243
1244 int umac_update(struct umac_ctx *ctx, u_char *input, long len)
1245 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1246 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1247 /* output buffer is full.                                                 */
1248 {
1249     uhash_update(&ctx->hash, input, len);
1250     return (1);
1251 }
1252
1253 /* ---------------------------------------------------------------------- */
1254
1255 #if 0
1256 int umac(struct umac_ctx *ctx, u_char *input,
1257          long len, u_char tag[],
1258          u_char nonce[8])
1259 /* All-in-one version simply calls umac_update() and umac_final().        */
1260 {
1261     uhash(&ctx->hash, input, len, (u_char *)tag);
1262     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1263
1264     return (1);
1265 }
1266 #endif
1267
1268 /* ---------------------------------------------------------------------- */
1269 /* ---------------------------------------------------------------------- */
1270 /* ----- End UMAC Section ----------------------------------------------- */
1271 /* ---------------------------------------------------------------------- */
1272 /* ---------------------------------------------------------------------- */