crypto/openssh/umac.c

   1 /* $OpenBSD: umac.c,v 1.11 2014/07/22 07:13:42 guenther Exp $ */
   2 /* -----------------------------------------------------------------------
   3  *
   4  * umac.c -- C Implementation UMAC Message Authentication
   5  *
   6  * Version 0.93b of rfc4418.txt -- 2006 July 18
   7  *
   8  * For a full description of UMAC message authentication see the UMAC
   9  * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac
  10  * Please report bugs and suggestions to the UMAC webpage.
  11  *
  12  * Copyright (c) 1999-2006 Ted Krovetz
  13  *
  14  * Permission to use, copy, modify, and distribute this software and
  15  * its documentation for any purpose and with or without fee, is hereby
  16  * granted provided that the above copyright notice appears in all copies
  17  * and in supporting documentation, and that the name of the copyright
  18  * holder not be used in advertising or publicity pertaining to
  19  * distribution of the software without specific, written prior permission.
  20  *
  21  * Comments should be directed to Ted Krovetz (tdk@acm.org)
  22  *
  23  * ---------------------------------------------------------------------- */
  24
  25  /* ////////////////////// IMPORTANT NOTES /////////////////////////////////
  26   *
  27   * 1) This version does not work properly on messages larger than 16MB
  28   *
  29   * 2) If you set the switch to use SSE2, then all data must be 16-byte
  30   *    aligned
  31   *
  32   * 3) When calling the function umac(), it is assumed that msg is in
  33   * a writable buffer of length divisible by 32 bytes. The message itself
  34   * does not have to fill the entire buffer, but bytes beyond msg may be
  35   * zeroed.
  36   *
  37   * 4) Three free AES implementations are supported by this implementation of
  38   * UMAC. Paulo Barreto's version is in the public domain and can be found
  39   * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for
  40   * "Barreto"). The only two files needed are rijndael-alg-fst.c and
  41   * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU
  42   * Public lisence at http://fp.gladman.plus.com/AES/index.htm. It
  43   * includes a fast IA-32 assembly version. The OpenSSL crypo library is
  44   * the third.
  45   *
  46   * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes
  47   * produced under gcc with optimizations set -O3 or higher. Dunno why.
  48   *
  49   /////////////////////////////////////////////////////////////////////// */
  50
  51 /* ---------------------------------------------------------------------- */
  52 /* --- User Switches ---------------------------------------------------- */
  53 /* ---------------------------------------------------------------------- */
  54
  55 #ifndef UMAC_OUTPUT_LEN
  56 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
  57 #endif
  58
  59 #if UMAC_OUTPUT_LEN != 4 && UMAC_OUTPUT_LEN != 8 && \
  60     UMAC_OUTPUT_LEN != 12 && UMAC_OUTPUT_LEN != 16
  61 # error UMAC_OUTPUT_LEN must be defined to 4, 8, 12 or 16
  62 #endif
  63
  64 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
  65 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
  66 /* #define SSE2                0  Is SSE2 is available?                   */
  67 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
  68 /* #define UMAC_AE_SUPPORT     0  Enable auhthenticated encrytion         */
  69
  70 /* ---------------------------------------------------------------------- */
  71 /* -- Global Includes --------------------------------------------------- */
  72 /* ---------------------------------------------------------------------- */
  73
  74 #include "includes.h"
  75 #include <sys/types.h>
  76 #include <string.h>
  77 #include <stdio.h>
  78 #include <stdlib.h>
  79 #include <stddef.h>
  80
  81 #include "xmalloc.h"
  82 #include "umac.h"
  83 #include "misc.h"
  84
  85 /* ---------------------------------------------------------------------- */
  86 /* --- Primitive Data Types ---                                           */
  87 /* ---------------------------------------------------------------------- */
  88
  89 /* The following assumptions may need change on your system */
  90 typedef u_int8_t        UINT8;  /* 1 byte   */
  91 typedef u_int16_t       UINT16; /* 2 byte   */
  92 typedef u_int32_t       UINT32; /* 4 byte   */
  93 typedef u_int64_t       UINT64; /* 8 bytes  */
  94 typedef unsigned int    UWORD;  /* Register */
  95
  96 /* ---------------------------------------------------------------------- */
  97 /* --- Constants -------------------------------------------------------- */
  98 /* ---------------------------------------------------------------------- */
  99
 100 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
 101
 102 /* Message "words" are read from memory in an endian-specific manner.     */
 103 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
 104 /* be set true if the host computer is little-endian.                     */
 105
 106 #if BYTE_ORDER == LITTLE_ENDIAN
 107 #define __LITTLE_ENDIAN__ 1
 108 #else
 109 #define __LITTLE_ENDIAN__ 0
 110 #endif
 111
 112 /* ---------------------------------------------------------------------- */
 113 /* ---------------------------------------------------------------------- */
 114 /* ----- Architecture Specific ------------------------------------------ */
 115 /* ---------------------------------------------------------------------- */
 116 /* ---------------------------------------------------------------------- */
 117
 118
 119 /* ---------------------------------------------------------------------- */
 120 /* ---------------------------------------------------------------------- */
 121 /* ----- Primitive Routines --------------------------------------------- */
 122 /* ---------------------------------------------------------------------- */
 123 /* ---------------------------------------------------------------------- */
 124
 125
 126 /* ---------------------------------------------------------------------- */
 127 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
 128 /* ---------------------------------------------------------------------- */
 129
 130 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
 131
 132 /* ---------------------------------------------------------------------- */
 133 /* --- Endian Conversion --- Forcing assembly on some platforms           */
 134 /* ---------------------------------------------------------------------- */
 135
 136 #if (__LITTLE_ENDIAN__)
 137 #define LOAD_UINT32_REVERSED(p)         get_u32(p)
 138 #define STORE_UINT32_REVERSED(p,v)      put_u32(p,v)
 139 #else
 140 #define LOAD_UINT32_REVERSED(p)         get_u32_le(p)
 141 #define STORE_UINT32_REVERSED(p,v)      put_u32_le(p,v)
 142 #endif
 143
 144 #define LOAD_UINT32_LITTLE(p)           (get_u32_le(p))
 145 #define STORE_UINT32_BIG(p,v)           put_u32(p, v)
 146
 147 /* ---------------------------------------------------------------------- */
 148 /* ---------------------------------------------------------------------- */
 149 /* ----- Begin KDF & PDF Section ---------------------------------------- */
 150 /* ---------------------------------------------------------------------- */
 151 /* ---------------------------------------------------------------------- */
 152
 153 /* UMAC uses AES with 16 byte block and key lengths */
 154 #define AES_BLOCK_LEN  16
 155
 156 /* OpenSSL's AES */
 157 #ifdef WITH_OPENSSL
 158 #include "openbsd-compat/openssl-compat.h"
 159 #ifndef USE_BUILTIN_RIJNDAEL
 160 # include <openssl/aes.h>
 161 #endif
 162 typedef AES_KEY aes_int_key[1];
 163 #define aes_encryption(in,out,int_key)                  \
 164   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
 165 #define aes_key_setup(key,int_key)                      \
 166   AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key)
 167 #else
 168 #include "rijndael.h"
 169 #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6)
 170 typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4];  /* AES internal */
 171 #define aes_encryption(in,out,int_key) \
 172   rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out))
 173 #define aes_key_setup(key,int_key) \
 174   rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \
 175   UMAC_KEY_LEN*8)
 176 #endif
 177
 178 /* The user-supplied UMAC key is stretched using AES in a counter
 179  * mode to supply all random bits needed by UMAC. The kdf function takes
 180  * an AES internal key representation 'key' and writes a stream of
 181  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
 182  * 'ndx' causes a distinct byte stream.
 183  */
 184 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
 185 {
 186     UINT8 in_buf[AES_BLOCK_LEN] = {0};
 187     UINT8 out_buf[AES_BLOCK_LEN];
 188     UINT8 *dst_buf = (UINT8 *)bufp;
 189     int i;
 190
 191     /* Setup the initial value */
 192     in_buf[AES_BLOCK_LEN-9] = ndx;
 193     in_buf[AES_BLOCK_LEN-1] = i = 1;
 194
 195     while (nbytes >= AES_BLOCK_LEN) {
 196         aes_encryption(in_buf, out_buf, key);
 197         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
 198         in_buf[AES_BLOCK_LEN-1] = ++i;
 199         nbytes -= AES_BLOCK_LEN;
 200         dst_buf += AES_BLOCK_LEN;
 201     }
 202     if (nbytes) {
 203         aes_encryption(in_buf, out_buf, key);
 204         memcpy(dst_buf,out_buf,nbytes);
 205     }
 206 }
 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, const 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     union {
 247         UINT8 tmp_nonce_lo[4];
 248         UINT32 align;
 249     } t;
 250 #if LOW_BIT_MASK != 0
 251     int ndx = nonce[7] & LOW_BIT_MASK;
 252 #endif
 253     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
 254     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
 255
 256     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
 257          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
 258     {
 259         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
 260         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
 261         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 262     }
 263
 264 #if (UMAC_OUTPUT_LEN == 4)
 265     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
 266 #elif (UMAC_OUTPUT_LEN == 8)
 267     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
 268 #elif (UMAC_OUTPUT_LEN == 12)
 269     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 270     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
 271 #elif (UMAC_OUTPUT_LEN == 16)
 272     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 273     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
 274 #endif
 275 }
 276
 277 /* ---------------------------------------------------------------------- */
 278 /* ---------------------------------------------------------------------- */
 279 /* ----- Begin NH Hash Section ------------------------------------------ */
 280 /* ---------------------------------------------------------------------- */
 281 /* ---------------------------------------------------------------------- */
 282
 283 /* The NH-based hash functions used in UMAC are described in the UMAC paper
 284  * and specification, both of which can be found at the UMAC website.
 285  * The interface to this implementation has two
 286  * versions, one expects the entire message being hashed to be passed
 287  * in a single buffer and returns the hash result immediately. The second
 288  * allows the message to be passed in a sequence of buffers. In the
 289  * muliple-buffer interface, the client calls the routine nh_update() as
 290  * many times as necessary. When there is no more data to be fed to the
 291  * hash, the client calls nh_final() which calculates the hash output.
 292  * Before beginning another hash calculation the nh_reset() routine
 293  * must be called. The single-buffer routine, nh(), is equivalent to
 294  * the sequence of calls nh_update() and nh_final(); however it is
 295  * optimized and should be prefered whenever the multiple-buffer interface
 296  * is not necessary. When using either interface, it is the client's
 297  * responsability to pass no more than L1_KEY_LEN bytes per hash result.
 298  *
 299  * The routine nh_init() initializes the nh_ctx data structure and
 300  * must be called once, before any other PDF routine.
 301  */
 302
 303  /* The "nh_aux" routines do the actual NH hashing work. They
 304   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
 305   * produce output for all STREAMS NH iterations in one call,
 306   * allowing the parallel implementation of the streams.
 307   */
 308
 309 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
 310 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
 311 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
 312 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
 313 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
 314 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
 315
 316 typedef struct {
 317     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
 318     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
 319     int next_data_empty;    /* Bookeeping variable for data buffer.       */
 320     int bytes_hashed;        /* Bytes (out of L1_KEY_LEN) incorperated.   */
 321     UINT64 state[STREAMS];               /* on-line state     */
 322 } nh_ctx;
 323
 324
 325 #if (UMAC_OUTPUT_LEN == 4)
 326
 327 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 328 /* NH hashing primitive. Previous (partial) hash result is loaded and
 329 * then stored via hp pointer. The length of the data pointed at by "dp",
 330 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
 331 * is expected to be endian compensated in memory at key setup.
 332 */
 333 {
 334     UINT64 h;
 335     UWORD c = dlen / 32;
 336     UINT32 *k = (UINT32 *)kp;
 337     const UINT32 *d = (const UINT32 *)dp;
 338     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 339     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
 340
 341     h = *((UINT64 *)hp);
 342     do {
 343         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 344         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 345         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 346         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 347         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 348         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 349         h += MUL64((k0 + d0), (k4 + d4));
 350         h += MUL64((k1 + d1), (k5 + d5));
 351         h += MUL64((k2 + d2), (k6 + d6));
 352         h += MUL64((k3 + d3), (k7 + d7));
 353
 354         d += 8;
 355         k += 8;
 356     } while (--c);
 357   *((UINT64 *)hp) = h;
 358 }
 359
 360 #elif (UMAC_OUTPUT_LEN == 8)
 361
 362 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 363 /* Same as previous nh_aux, but two streams are handled in one pass,
 364  * reading and writing 16 bytes of hash-state per call.
 365  */
 366 {
 367   UINT64 h1,h2;
 368   UWORD c = dlen / 32;
 369   UINT32 *k = (UINT32 *)kp;
 370   const UINT32 *d = (const UINT32 *)dp;
 371   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 372   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 373         k8,k9,k10,k11;
 374
 375   h1 = *((UINT64 *)hp);
 376   h2 = *((UINT64 *)hp + 1);
 377   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 378   do {
 379     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 380     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 381     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 382     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 383     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 384     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 385
 386     h1 += MUL64((k0 + d0), (k4 + d4));
 387     h2 += MUL64((k4 + d0), (k8 + d4));
 388
 389     h1 += MUL64((k1 + d1), (k5 + d5));
 390     h2 += MUL64((k5 + d1), (k9 + d5));
 391
 392     h1 += MUL64((k2 + d2), (k6 + d6));
 393     h2 += MUL64((k6 + d2), (k10 + d6));
 394
 395     h1 += MUL64((k3 + d3), (k7 + d7));
 396     h2 += MUL64((k7 + d3), (k11 + d7));
 397
 398     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 399
 400     d += 8;
 401     k += 8;
 402   } while (--c);
 403   ((UINT64 *)hp)[0] = h1;
 404   ((UINT64 *)hp)[1] = h2;
 405 }
 406
 407 #elif (UMAC_OUTPUT_LEN == 12)
 408
 409 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 410 /* Same as previous nh_aux, but two streams are handled in one pass,
 411  * reading and writing 24 bytes of hash-state per call.
 412 */
 413 {
 414     UINT64 h1,h2,h3;
 415     UWORD c = dlen / 32;
 416     UINT32 *k = (UINT32 *)kp;
 417     const UINT32 *d = (const UINT32 *)dp;
 418     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 419     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 420         k8,k9,k10,k11,k12,k13,k14,k15;
 421
 422     h1 = *((UINT64 *)hp);
 423     h2 = *((UINT64 *)hp + 1);
 424     h3 = *((UINT64 *)hp + 2);
 425     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 426     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 427     do {
 428         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 429         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 430         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 431         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 432         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 433         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 434
 435         h1 += MUL64((k0 + d0), (k4 + d4));
 436         h2 += MUL64((k4 + d0), (k8 + d4));
 437         h3 += MUL64((k8 + d0), (k12 + d4));
 438
 439         h1 += MUL64((k1 + d1), (k5 + d5));
 440         h2 += MUL64((k5 + d1), (k9 + d5));
 441         h3 += MUL64((k9 + d1), (k13 + d5));
 442
 443         h1 += MUL64((k2 + d2), (k6 + d6));
 444         h2 += MUL64((k6 + d2), (k10 + d6));
 445         h3 += MUL64((k10 + d2), (k14 + d6));
 446
 447         h1 += MUL64((k3 + d3), (k7 + d7));
 448         h2 += MUL64((k7 + d3), (k11 + d7));
 449         h3 += MUL64((k11 + d3), (k15 + d7));
 450
 451         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 452         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 453
 454         d += 8;
 455         k += 8;
 456     } while (--c);
 457     ((UINT64 *)hp)[0] = h1;
 458     ((UINT64 *)hp)[1] = h2;
 459     ((UINT64 *)hp)[2] = h3;
 460 }
 461
 462 #elif (UMAC_OUTPUT_LEN == 16)
 463
 464 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 465 /* Same as previous nh_aux, but two streams are handled in one pass,
 466  * reading and writing 24 bytes of hash-state per call.
 467 */
 468 {
 469     UINT64 h1,h2,h3,h4;
 470     UWORD c = dlen / 32;
 471     UINT32 *k = (UINT32 *)kp;
 472     const UINT32 *d = (const UINT32 *)dp;
 473     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 474     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 475         k8,k9,k10,k11,k12,k13,k14,k15,
 476         k16,k17,k18,k19;
 477
 478     h1 = *((UINT64 *)hp);
 479     h2 = *((UINT64 *)hp + 1);
 480     h3 = *((UINT64 *)hp + 2);
 481     h4 = *((UINT64 *)hp + 3);
 482     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 483     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 484     do {
 485         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 486         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 487         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 488         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 489         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 490         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 491         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
 492
 493         h1 += MUL64((k0 + d0), (k4 + d4));
 494         h2 += MUL64((k4 + d0), (k8 + d4));
 495         h3 += MUL64((k8 + d0), (k12 + d4));
 496         h4 += MUL64((k12 + d0), (k16 + d4));
 497
 498         h1 += MUL64((k1 + d1), (k5 + d5));
 499         h2 += MUL64((k5 + d1), (k9 + d5));
 500         h3 += MUL64((k9 + d1), (k13 + d5));
 501         h4 += MUL64((k13 + d1), (k17 + d5));
 502
 503         h1 += MUL64((k2 + d2), (k6 + d6));
 504         h2 += MUL64((k6 + d2), (k10 + d6));
 505         h3 += MUL64((k10 + d2), (k14 + d6));
 506         h4 += MUL64((k14 + d2), (k18 + d6));
 507
 508         h1 += MUL64((k3 + d3), (k7 + d7));
 509         h2 += MUL64((k7 + d3), (k11 + d7));
 510         h3 += MUL64((k11 + d3), (k15 + d7));
 511         h4 += MUL64((k15 + d3), (k19 + d7));
 512
 513         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 514         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 515         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
 516
 517         d += 8;
 518         k += 8;
 519     } while (--c);
 520     ((UINT64 *)hp)[0] = h1;
 521     ((UINT64 *)hp)[1] = h2;
 522     ((UINT64 *)hp)[2] = h3;
 523     ((UINT64 *)hp)[3] = h4;
 524 }
 525
 526 /* ---------------------------------------------------------------------- */
 527 #endif  /* UMAC_OUTPUT_LENGTH */
 528 /* ---------------------------------------------------------------------- */
 529
 530
 531 /* ---------------------------------------------------------------------- */
 532
 533 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
 534 /* This function is a wrapper for the primitive NH hash functions. It takes
 535  * as argument "hc" the current hash context and a buffer which must be a
 536  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
 537  * appropriately according to how much message has been hashed already.
 538  */
 539 {
 540     UINT8 *key;
 541
 542     key = hc->nh_key + hc->bytes_hashed;
 543     nh_aux(key, buf, hc->state, nbytes);
 544 }
 545
 546 /* ---------------------------------------------------------------------- */
 547
 548 #if (__LITTLE_ENDIAN__)
 549 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
 550 /* We endian convert the keys on little-endian computers to               */
 551 /* compensate for the lack of big-endian memory reads during hashing.     */
 552 {
 553     UWORD iters = num_bytes / bpw;
 554     if (bpw == 4) {
 555         UINT32 *p = (UINT32 *)buf;
 556         do {
 557             *p = LOAD_UINT32_REVERSED(p);
 558             p++;
 559         } while (--iters);
 560     } else if (bpw == 8) {
 561         UINT32 *p = (UINT32 *)buf;
 562         UINT32 t;
 563         do {
 564             t = LOAD_UINT32_REVERSED(p+1);
 565             p[1] = LOAD_UINT32_REVERSED(p);
 566             p[0] = t;
 567             p += 2;
 568         } while (--iters);
 569     }
 570 }
 571 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
 572 #else
 573 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
 574 #endif
 575
 576 /* ---------------------------------------------------------------------- */
 577
 578 static void nh_reset(nh_ctx *hc)
 579 /* Reset nh_ctx to ready for hashing of new data */
 580 {
 581     hc->bytes_hashed = 0;
 582     hc->next_data_empty = 0;
 583     hc->state[0] = 0;
 584 #if (UMAC_OUTPUT_LEN >= 8)
 585     hc->state[1] = 0;
 586 #endif
 587 #if (UMAC_OUTPUT_LEN >= 12)
 588     hc->state[2] = 0;
 589 #endif
 590 #if (UMAC_OUTPUT_LEN == 16)
 591     hc->state[3] = 0;
 592 #endif
 593
 594 }
 595
 596 /* ---------------------------------------------------------------------- */
 597
 598 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
 599 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
 600 {
 601     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
 602     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
 603     nh_reset(hc);
 604 }
 605
 606 /* ---------------------------------------------------------------------- */
 607
 608 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
 609 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
 610 /* even multiple of HASH_BUF_BYTES.                                       */
 611 {
 612     UINT32 i,j;
 613
 614     j = hc->next_data_empty;
 615     if ((j + nbytes) >= HASH_BUF_BYTES) {
 616         if (j) {
 617             i = HASH_BUF_BYTES - j;
 618             memcpy(hc->data+j, buf, i);
 619             nh_transform(hc,hc->data,HASH_BUF_BYTES);
 620             nbytes -= i;
 621             buf += i;
 622             hc->bytes_hashed += HASH_BUF_BYTES;
 623         }
 624         if (nbytes >= HASH_BUF_BYTES) {
 625             i = nbytes & ~(HASH_BUF_BYTES - 1);
 626             nh_transform(hc, buf, i);
 627             nbytes -= i;
 628             buf += i;
 629             hc->bytes_hashed += i;
 630         }
 631         j = 0;
 632     }
 633     memcpy(hc->data + j, buf, nbytes);
 634     hc->next_data_empty = j + nbytes;
 635 }
 636
 637 /* ---------------------------------------------------------------------- */
 638
 639 static void zero_pad(UINT8 *p, int nbytes)
 640 {
 641 /* Write "nbytes" of zeroes, beginning at "p" */
 642     if (nbytes >= (int)sizeof(UWORD)) {
 643         while ((ptrdiff_t)p % sizeof(UWORD)) {
 644             *p = 0;
 645             nbytes--;
 646             p++;
 647         }
 648         while (nbytes >= (int)sizeof(UWORD)) {
 649             *(UWORD *)p = 0;
 650             nbytes -= sizeof(UWORD);
 651             p += sizeof(UWORD);
 652         }
 653     }
 654     while (nbytes) {
 655         *p = 0;
 656         nbytes--;
 657         p++;
 658     }
 659 }
 660
 661 /* ---------------------------------------------------------------------- */
 662
 663 static void nh_final(nh_ctx *hc, UINT8 *result)
 664 /* After passing some number of data buffers to nh_update() for integration
 665  * into an NH context, nh_final is called to produce a hash result. If any
 666  * bytes are in the buffer hc->data, incorporate them into the
 667  * NH context. Finally, add into the NH accumulation "state" the total number
 668  * of bits hashed. The resulting numbers are written to the buffer "result".
 669  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
 670  */
 671 {
 672     int nh_len, nbits;
 673
 674     if (hc->next_data_empty != 0) {
 675         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
 676                                                 ~(L1_PAD_BOUNDARY - 1));
 677         zero_pad(hc->data + hc->next_data_empty,
 678                                           nh_len - hc->next_data_empty);
 679         nh_transform(hc, hc->data, nh_len);
 680         hc->bytes_hashed += hc->next_data_empty;
 681     } else if (hc->bytes_hashed == 0) {
 682         nh_len = L1_PAD_BOUNDARY;
 683         zero_pad(hc->data, L1_PAD_BOUNDARY);
 684         nh_transform(hc, hc->data, nh_len);
 685     }
 686
 687     nbits = (hc->bytes_hashed << 3);
 688     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
 689 #if (UMAC_OUTPUT_LEN >= 8)
 690     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
 691 #endif
 692 #if (UMAC_OUTPUT_LEN >= 12)
 693     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
 694 #endif
 695 #if (UMAC_OUTPUT_LEN == 16)
 696     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
 697 #endif
 698     nh_reset(hc);
 699 }
 700
 701 /* ---------------------------------------------------------------------- */
 702
 703 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
 704                UINT32 unpadded_len, UINT8 *result)
 705 /* All-in-one nh_update() and nh_final() equivalent.
 706  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
 707  * well aligned
 708  */
 709 {
 710     UINT32 nbits;
 711
 712     /* Initialize the hash state */
 713     nbits = (unpadded_len << 3);
 714
 715     ((UINT64 *)result)[0] = nbits;
 716 #if (UMAC_OUTPUT_LEN >= 8)
 717     ((UINT64 *)result)[1] = nbits;
 718 #endif
 719 #if (UMAC_OUTPUT_LEN >= 12)
 720     ((UINT64 *)result)[2] = nbits;
 721 #endif
 722 #if (UMAC_OUTPUT_LEN == 16)
 723     ((UINT64 *)result)[3] = nbits;
 724 #endif
 725
 726     nh_aux(hc->nh_key, buf, result, padded_len);
 727 }
 728
 729 /* ---------------------------------------------------------------------- */
 730 /* ---------------------------------------------------------------------- */
 731 /* ----- Begin UHASH Section -------------------------------------------- */
 732 /* ---------------------------------------------------------------------- */
 733 /* ---------------------------------------------------------------------- */
 734
 735 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
 736  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
 737  * unless the initial data to be hashed is short. After the polynomial-
 738  * layer, an inner-product hash is used to produce the final UHASH output.
 739  *
 740  * UHASH provides two interfaces, one all-at-once and another where data
 741  * buffers are presented sequentially. In the sequential interface, the
 742  * UHASH client calls the routine uhash_update() as many times as necessary.
 743  * When there is no more data to be fed to UHASH, the client calls
 744  * uhash_final() which
 745  * calculates the UHASH output. Before beginning another UHASH calculation
 746  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
 747  * uhash(), is equivalent to the sequence of calls uhash_update() and
 748  * uhash_final(); however it is optimized and should be
 749  * used whenever the sequential interface is not necessary.
 750  *
 751  * The routine uhash_init() initializes the uhash_ctx data structure and
 752  * must be called once, before any other UHASH routine.
 753  */
 754
 755 /* ---------------------------------------------------------------------- */
 756 /* ----- Constants and uhash_ctx ---------------------------------------- */
 757 /* ---------------------------------------------------------------------- */
 758
 759 /* ---------------------------------------------------------------------- */
 760 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
 761 /* ---------------------------------------------------------------------- */
 762
 763 /* Primes and masks */
 764 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
 765 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
 766 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
 767
 768
 769 /* ---------------------------------------------------------------------- */
 770
 771 typedef struct uhash_ctx {
 772     nh_ctx hash;                          /* Hash context for L1 NH hash  */
 773     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
 774     UINT64 poly_accum[STREAMS];           /* poly hash result             */
 775     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
 776     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
 777     UINT32 msg_len;                       /* Total length of data passed  */
 778                                           /* to uhash */
 779 } uhash_ctx;
 780 typedef struct uhash_ctx *uhash_ctx_t;
 781
 782 /* ---------------------------------------------------------------------- */
 783
 784
 785 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
 786  * word at a time. As described in the specification, poly32 and poly64
 787  * require keys from special domains. The following implementations exploit
 788  * the special domains to avoid overflow. The results are not guaranteed to
 789  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
 790  * patches any errant values.
 791  */
 792
 793 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
 794 {
 795     UINT32 key_hi = (UINT32)(key >> 32),
 796            key_lo = (UINT32)key,
 797            cur_hi = (UINT32)(cur >> 32),
 798            cur_lo = (UINT32)cur,
 799            x_lo,
 800            x_hi;
 801     UINT64 X,T,res;
 802
 803     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
 804     x_lo = (UINT32)X;
 805     x_hi = (UINT32)(X >> 32);
 806
 807     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
 808
 809     T = ((UINT64)x_lo << 32);
 810     res += T;
 811     if (res < T)
 812         res += 59;
 813
 814     res += data;
 815     if (res < data)
 816         res += 59;
 817
 818     return res;
 819 }
 820
 821
 822 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
 823  * implementation does not handle all ramp levels. Because we don't handle
 824  * the ramp up to p128 modulus in this implementation, we are limited to
 825  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
 826  * bytes input to UMAC per tag, ie. 16MB).
 827  */
 828 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
 829 {
 830     int i;
 831     UINT64 *data=(UINT64*)data_in;
 832
 833     for (i = 0; i < STREAMS; i++) {
 834         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
 835             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 836                                        hc->poly_key_8[i], p64 - 1);
 837             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 838                                        hc->poly_key_8[i], (data[i] - 59));
 839         } else {
 840             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 841                                        hc->poly_key_8[i], data[i]);
 842         }
 843     }
 844 }
 845
 846
 847 /* ---------------------------------------------------------------------- */
 848
 849
 850 /* The final step in UHASH is an inner-product hash. The poly hash
 851  * produces a result not neccesarily WORD_LEN bytes long. The inner-
 852  * product hash breaks the polyhash output into 16-bit chunks and
 853  * multiplies each with a 36 bit key.
 854  */
 855
 856 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
 857 {
 858     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
 859     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
 860     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
 861     t = t + ipkp[3] * (UINT64)(UINT16)(data);
 862
 863     return t;
 864 }
 865
 866 static UINT32 ip_reduce_p36(UINT64 t)
 867 {
 868 /* Divisionless modular reduction */
 869     UINT64 ret;
 870
 871     ret = (t & m36) + 5 * (t >> 36);
 872     if (ret >= p36)
 873         ret -= p36;
 874
 875     /* return least significant 32 bits */
 876     return (UINT32)(ret);
 877 }
 878
 879
 880 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
 881  * the polyhash stage is skipped and ip_short is applied directly to the
 882  * NH output.
 883  */
 884 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
 885 {
 886     UINT64 t;
 887     UINT64 *nhp = (UINT64 *)nh_res;
 888
 889     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
 890     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
 891 #if (UMAC_OUTPUT_LEN >= 8)
 892     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
 893     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
 894 #endif
 895 #if (UMAC_OUTPUT_LEN >= 12)
 896     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
 897     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
 898 #endif
 899 #if (UMAC_OUTPUT_LEN == 16)
 900     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
 901     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
 902 #endif
 903 }
 904
 905 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
 906  * the polyhash stage is not skipped and ip_long is applied to the
 907  * polyhash output.
 908  */
 909 static void ip_long(uhash_ctx_t ahc, u_char *res)
 910 {
 911     int i;
 912     UINT64 t;
 913
 914     for (i = 0; i < STREAMS; i++) {
 915         /* fix polyhash output not in Z_p64 */
 916         if (ahc->poly_accum[i] >= p64)
 917             ahc->poly_accum[i] -= p64;
 918         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
 919         STORE_UINT32_BIG((UINT32 *)res+i,
 920                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
 921     }
 922 }
 923
 924
 925 /* ---------------------------------------------------------------------- */
 926
 927 /* ---------------------------------------------------------------------- */
 928
 929 /* Reset uhash context for next hash session */
 930 static int uhash_reset(uhash_ctx_t pc)
 931 {
 932     nh_reset(&pc->hash);
 933     pc->msg_len = 0;
 934     pc->poly_accum[0] = 1;
 935 #if (UMAC_OUTPUT_LEN >= 8)
 936     pc->poly_accum[1] = 1;
 937 #endif
 938 #if (UMAC_OUTPUT_LEN >= 12)
 939     pc->poly_accum[2] = 1;
 940 #endif
 941 #if (UMAC_OUTPUT_LEN == 16)
 942     pc->poly_accum[3] = 1;
 943 #endif
 944     return 1;
 945 }
 946
 947 /* ---------------------------------------------------------------------- */
 948
 949 /* Given a pointer to the internal key needed by kdf() and a uhash context,
 950  * initialize the NH context and generate keys needed for poly and inner-
 951  * product hashing. All keys are endian adjusted in memory so that native
 952  * loads cause correct keys to be in registers during calculation.
 953  */
 954 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
 955 {
 956     int i;
 957     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
 958
 959     /* Zero the entire uhash context */
 960     memset(ahc, 0, sizeof(uhash_ctx));
 961
 962     /* Initialize the L1 hash */
 963     nh_init(&ahc->hash, prf_key);
 964
 965     /* Setup L2 hash variables */
 966     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
 967     for (i = 0; i < STREAMS; i++) {
 968         /* Fill keys from the buffer, skipping bytes in the buffer not
 969          * used by this implementation. Endian reverse the keys if on a
 970          * little-endian computer.
 971          */
 972         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
 973         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
 974         /* Mask the 64-bit keys to their special domain */
 975         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
 976         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
 977     }
 978
 979     /* Setup L3-1 hash variables */
 980     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
 981     for (i = 0; i < STREAMS; i++)
 982           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
 983                                                  4*sizeof(UINT64));
 984     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
 985                                                   sizeof(ahc->ip_keys));
 986     for (i = 0; i < STREAMS*4; i++)
 987         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
 988
 989     /* Setup L3-2 hash variables    */
 990     /* Fill buffer with index 4 key */
 991     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
 992     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
 993                          STREAMS * sizeof(UINT32));
 994 }
 995
 996 /* ---------------------------------------------------------------------- */
 997
 998 #if 0
 999 static uhash_ctx_t uhash_alloc(u_char key[])
1000 {
1001 /* Allocate memory and force to a 16-byte boundary. */
1002     uhash_ctx_t ctx;
1003     u_char bytes_to_add;
1004     aes_int_key prf_key;
1005
1006     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1007     if (ctx) {
1008         if (ALLOC_BOUNDARY) {
1009             bytes_to_add = ALLOC_BOUNDARY -
1010                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1011             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1012             *((u_char *)ctx - 1) = bytes_to_add;
1013         }
1014         aes_key_setup(key,prf_key);
1015         uhash_init(ctx, prf_key);
1016     }
1017     return (ctx);
1018 }
1019 #endif
1020
1021 /* ---------------------------------------------------------------------- */
1022
1023 #if 0
1024 static int uhash_free(uhash_ctx_t ctx)
1025 {
1026 /* Free memory allocated by uhash_alloc */
1027     u_char bytes_to_sub;
1028
1029     if (ctx) {
1030         if (ALLOC_BOUNDARY) {
1031             bytes_to_sub = *((u_char *)ctx - 1);
1032             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1033         }
1034         free(ctx);
1035     }
1036     return (1);
1037 }
1038 #endif
1039 /* ---------------------------------------------------------------------- */
1040
1041 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1042 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1043  * hash each one with NH, calling the polyhash on each NH output.
1044  */
1045 {
1046     UWORD bytes_hashed, bytes_remaining;
1047     UINT64 result_buf[STREAMS];
1048     UINT8 *nh_result = (UINT8 *)&result_buf;
1049
1050     if (ctx->msg_len + len <= L1_KEY_LEN) {
1051         nh_update(&ctx->hash, (const UINT8 *)input, len);
1052         ctx->msg_len += len;
1053     } else {
1054
1055          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1056          if (ctx->msg_len == L1_KEY_LEN)
1057              bytes_hashed = L1_KEY_LEN;
1058
1059          if (bytes_hashed + len >= L1_KEY_LEN) {
1060
1061              /* If some bytes have been passed to the hash function      */
1062              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1063              /* bytes to complete the current nh_block.                  */
1064              if (bytes_hashed) {
1065                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1066                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1067                  nh_final(&ctx->hash, nh_result);
1068                  ctx->msg_len += bytes_remaining;
1069                  poly_hash(ctx,(UINT32 *)nh_result);
1070                  len -= bytes_remaining;
1071                  input += bytes_remaining;
1072              }
1073
1074              /* Hash directly from input stream if enough bytes */
1075              while (len >= L1_KEY_LEN) {
1076                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1077                                    L1_KEY_LEN, nh_result);
1078                  ctx->msg_len += L1_KEY_LEN;
1079                  len -= L1_KEY_LEN;
1080                  input += L1_KEY_LEN;
1081                  poly_hash(ctx,(UINT32 *)nh_result);
1082              }
1083          }
1084
1085          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1086          if (len) {
1087              nh_update(&ctx->hash, (const UINT8 *)input, len);
1088              ctx->msg_len += len;
1089          }
1090      }
1091
1092     return (1);
1093 }
1094
1095 /* ---------------------------------------------------------------------- */
1096
1097 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1098 /* Incorporate any pending data, pad, and generate tag */
1099 {
1100     UINT64 result_buf[STREAMS];
1101     UINT8 *nh_result = (UINT8 *)&result_buf;
1102
1103     if (ctx->msg_len > L1_KEY_LEN) {
1104         if (ctx->msg_len % L1_KEY_LEN) {
1105             nh_final(&ctx->hash, nh_result);
1106             poly_hash(ctx,(UINT32 *)nh_result);
1107         }
1108         ip_long(ctx, res);
1109     } else {
1110         nh_final(&ctx->hash, nh_result);
1111         ip_short(ctx,nh_result, res);
1112     }
1113     uhash_reset(ctx);
1114     return (1);
1115 }
1116
1117 /* ---------------------------------------------------------------------- */
1118
1119 #if 0
1120 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1121 /* assumes that msg is in a writable buffer of length divisible by */
1122 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1123 {
1124     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1125     UINT32 nh_len;
1126     int extra_zeroes_needed;
1127
1128     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1129      * the polyhash.
1130      */
1131     if (len <= L1_KEY_LEN) {
1132         if (len == 0)                  /* If zero length messages will not */
1133                 nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1134         else
1135                 nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1136         extra_zeroes_needed = nh_len - len;
1137         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1138         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1139         ip_short(ahc,nh_result, res);
1140     } else {
1141         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1142          * output to poly_hash().
1143          */
1144         do {
1145             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1146             poly_hash(ahc,(UINT32 *)nh_result);
1147             len -= L1_KEY_LEN;
1148             msg += L1_KEY_LEN;
1149         } while (len >= L1_KEY_LEN);
1150         if (len) {
1151             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1152             extra_zeroes_needed = nh_len - len;
1153             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1154             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1155             poly_hash(ahc,(UINT32 *)nh_result);
1156         }
1157
1158         ip_long(ahc, res);
1159     }
1160
1161     uhash_reset(ahc);
1162     return 1;
1163 }
1164 #endif
1165
1166 /* ---------------------------------------------------------------------- */
1167 /* ---------------------------------------------------------------------- */
1168 /* ----- Begin UMAC Section --------------------------------------------- */
1169 /* ---------------------------------------------------------------------- */
1170 /* ---------------------------------------------------------------------- */
1171
1172 /* The UMAC interface has two interfaces, an all-at-once interface where
1173  * the entire message to be authenticated is passed to UMAC in one buffer,
1174  * and a sequential interface where the message is presented a little at a
1175  * time. The all-at-once is more optimaized than the sequential version and
1176  * should be preferred when the sequential interface is not required.
1177  */
1178 struct umac_ctx {
1179     uhash_ctx hash;          /* Hash function for message compression    */
1180     pdf_ctx pdf;             /* PDF for hashed output                    */
1181     void *free_ptr;          /* Address to free this struct via          */
1182 } umac_ctx;
1183
1184 /* ---------------------------------------------------------------------- */
1185
1186 #if 0
1187 int umac_reset(struct umac_ctx *ctx)
1188 /* Reset the hash function to begin a new authentication.        */
1189 {
1190     uhash_reset(&ctx->hash);
1191     return (1);
1192 }
1193 #endif
1194
1195 /* ---------------------------------------------------------------------- */
1196
1197 int umac_delete(struct umac_ctx *ctx)
1198 /* Deallocate the ctx structure */
1199 {
1200     if (ctx) {
1201         if (ALLOC_BOUNDARY)
1202             ctx = (struct umac_ctx *)ctx->free_ptr;
1203         free(ctx);
1204     }
1205     return (1);
1206 }
1207
1208 /* ---------------------------------------------------------------------- */
1209
1210 struct umac_ctx *umac_new(const u_char key[])
1211 /* Dynamically allocate a umac_ctx struct, initialize variables,
1212  * generate subkeys from key. Align to 16-byte boundary.
1213  */
1214 {
1215     struct umac_ctx *ctx, *octx;
1216     size_t bytes_to_add;
1217     aes_int_key prf_key;
1218
1219     octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1220     if (ctx) {
1221         if (ALLOC_BOUNDARY) {
1222             bytes_to_add = ALLOC_BOUNDARY -
1223                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1224             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1225         }
1226         ctx->free_ptr = octx;
1227         aes_key_setup(key, prf_key);
1228         pdf_init(&ctx->pdf, prf_key);
1229         uhash_init(&ctx->hash, prf_key);
1230     }
1231
1232     return (ctx);
1233 }
1234
1235 /* ---------------------------------------------------------------------- */
1236
1237 int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1238 /* Incorporate any pending data, pad, and generate tag */
1239 {
1240     uhash_final(&ctx->hash, (u_char *)tag);
1241     pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1242
1243     return (1);
1244 }
1245
1246 /* ---------------------------------------------------------------------- */
1247
1248 int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1249 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1250 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1251 /* output buffer is full.                                                 */
1252 {
1253     uhash_update(&ctx->hash, input, len);
1254     return (1);
1255 }
1256
1257 /* ---------------------------------------------------------------------- */
1258
1259 #if 0
1260 int umac(struct umac_ctx *ctx, u_char *input,
1261          long len, u_char tag[],
1262          u_char nonce[8])
1263 /* All-in-one version simply calls umac_update() and umac_final().        */
1264 {
1265     uhash(&ctx->hash, input, len, (u_char *)tag);
1266     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1267
1268     return (1);
1269 }
1270 #endif
1271
1272 /* ---------------------------------------------------------------------- */
1273 /* ---------------------------------------------------------------------- */
1274 /* ----- End UMAC Section ----------------------------------------------- */
1275 /* ---------------------------------------------------------------------- */
1276 /* ---------------------------------------------------------------------- */