crypto/openssh/umac.c

   1 /* $OpenBSD: umac.c,v 1.22 2022/01/01 05:55:06 jsg Exp $ */
   2 /* -----------------------------------------------------------------------
   3  *
   4  * umac.c -- C Implementation UMAC Message Authentication
   5  *
   6  * Version 0.93b of rfc4418.txt -- 2006 July 18
   7  *
   8  * For a full description of UMAC message authentication see the UMAC
   9  * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac
  10  * Please report bugs and suggestions to the UMAC webpage.
  11  *
  12  * Copyright (c) 1999-2006 Ted Krovetz
  13  *
  14  * Permission to use, copy, modify, and distribute this software and
  15  * its documentation for any purpose and with or without fee, is hereby
  16  * granted provided that the above copyright notice appears in all copies
  17  * and in supporting documentation, and that the name of the copyright
  18  * holder not be used in advertising or publicity pertaining to
  19  * distribution of the software without specific, written prior permission.
  20  *
  21  * Comments should be directed to Ted Krovetz (tdk@acm.org)
  22  *
  23  * ---------------------------------------------------------------------- */
  24
  25  /* ////////////////////// IMPORTANT NOTES /////////////////////////////////
  26   *
  27   * 1) This version does not work properly on messages larger than 16MB
  28   *
  29   * 2) If you set the switch to use SSE2, then all data must be 16-byte
  30   *    aligned
  31   *
  32   * 3) When calling the function umac(), it is assumed that msg is in
  33   * a writable buffer of length divisible by 32 bytes. The message itself
  34   * does not have to fill the entire buffer, but bytes beyond msg may be
  35   * zeroed.
  36   *
  37   * 4) Three free AES implementations are supported by this implementation of
  38   * UMAC. Paulo Barreto's version is in the public domain and can be found
  39   * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for
  40   * "Barreto"). The only two files needed are rijndael-alg-fst.c and
  41   * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU
  42   * Public license at http://fp.gladman.plus.com/AES/index.htm. It
  43   * includes a fast IA-32 assembly version. The OpenSSL crypo library is
  44   * the third.
  45   *
  46   * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes
  47   * produced under gcc with optimizations set -O3 or higher. Dunno why.
  48   *
  49   /////////////////////////////////////////////////////////////////////// */
  50
  51 /* ---------------------------------------------------------------------- */
  52 /* --- User Switches ---------------------------------------------------- */
  53 /* ---------------------------------------------------------------------- */
  54
  55 #ifndef UMAC_OUTPUT_LEN
  56 #define UMAC_OUTPUT_LEN     8  /* Alowable: 4, 8, 12, 16                  */
  57 #endif
  58
  59 #if UMAC_OUTPUT_LEN != 4 && UMAC_OUTPUT_LEN != 8 && \
  60     UMAC_OUTPUT_LEN != 12 && UMAC_OUTPUT_LEN != 16
  61 # error UMAC_OUTPUT_LEN must be defined to 4, 8, 12 or 16
  62 #endif
  63
  64 /* #define FORCE_C_ONLY        1  ANSI C and 64-bit integers req'd        */
  65 /* #define AES_IMPLEMENTAION   1  1 = OpenSSL, 2 = Barreto, 3 = Gladman   */
  66 /* #define SSE2                0  Is SSE2 is available?                   */
  67 /* #define RUN_TESTS           0  Run basic correctness/speed tests       */
  68 /* #define UMAC_AE_SUPPORT     0  Enable authenticated encryption         */
  69
  70 /* ---------------------------------------------------------------------- */
  71 /* -- Global Includes --------------------------------------------------- */
  72 /* ---------------------------------------------------------------------- */
  73
  74 #include "includes.h"
  75 #include <sys/types.h>
  76 #include <string.h>
  77 #include <stdarg.h>
  78 #include <stdio.h>
  79 #include <stdlib.h>
  80 #include <stddef.h>
  81
  82 #include "xmalloc.h"
  83 #include "umac.h"
  84 #include "misc.h"
  85
  86 /* ---------------------------------------------------------------------- */
  87 /* --- Primitive Data Types ---                                           */
  88 /* ---------------------------------------------------------------------- */
  89
  90 /* The following assumptions may need change on your system */
  91 typedef u_int8_t        UINT8;  /* 1 byte   */
  92 typedef u_int16_t       UINT16; /* 2 byte   */
  93 typedef u_int32_t       UINT32; /* 4 byte   */
  94 typedef u_int64_t       UINT64; /* 8 bytes  */
  95 typedef unsigned int    UWORD;  /* Register */
  96
  97 /* ---------------------------------------------------------------------- */
  98 /* --- Constants -------------------------------------------------------- */
  99 /* ---------------------------------------------------------------------- */
 100
 101 #define UMAC_KEY_LEN           16  /* UMAC takes 16 bytes of external key */
 102
 103 /* Message "words" are read from memory in an endian-specific manner.     */
 104 /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must    */
 105 /* be set true if the host computer is little-endian.                     */
 106
 107 #if BYTE_ORDER == LITTLE_ENDIAN
 108 #define __LITTLE_ENDIAN__ 1
 109 #else
 110 #define __LITTLE_ENDIAN__ 0
 111 #endif
 112
 113 /* ---------------------------------------------------------------------- */
 114 /* ---------------------------------------------------------------------- */
 115 /* ----- Architecture Specific ------------------------------------------ */
 116 /* ---------------------------------------------------------------------- */
 117 /* ---------------------------------------------------------------------- */
 118
 119
 120 /* ---------------------------------------------------------------------- */
 121 /* ---------------------------------------------------------------------- */
 122 /* ----- Primitive Routines --------------------------------------------- */
 123 /* ---------------------------------------------------------------------- */
 124 /* ---------------------------------------------------------------------- */
 125
 126
 127 /* ---------------------------------------------------------------------- */
 128 /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */
 129 /* ---------------------------------------------------------------------- */
 130
 131 #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b)))
 132
 133 /* ---------------------------------------------------------------------- */
 134 /* --- Endian Conversion --- Forcing assembly on some platforms           */
 135 /* ---------------------------------------------------------------------- */
 136
 137 #if (__LITTLE_ENDIAN__)
 138 #define LOAD_UINT32_REVERSED(p)         get_u32(p)
 139 #define STORE_UINT32_REVERSED(p,v)      put_u32(p,v)
 140 #else
 141 #define LOAD_UINT32_REVERSED(p)         get_u32_le(p)
 142 #define STORE_UINT32_REVERSED(p,v)      put_u32_le(p,v)
 143 #endif
 144
 145 #define LOAD_UINT32_LITTLE(p)           (get_u32_le(p))
 146 #define STORE_UINT32_BIG(p,v)           put_u32(p, v)
 147
 148 /* ---------------------------------------------------------------------- */
 149 /* ---------------------------------------------------------------------- */
 150 /* ----- Begin KDF & PDF Section ---------------------------------------- */
 151 /* ---------------------------------------------------------------------- */
 152 /* ---------------------------------------------------------------------- */
 153
 154 /* UMAC uses AES with 16 byte block and key lengths */
 155 #define AES_BLOCK_LEN  16
 156
 157 /* OpenSSL's AES */
 158 #ifdef WITH_OPENSSL
 159 #include "openbsd-compat/openssl-compat.h"
 160 #ifndef USE_BUILTIN_RIJNDAEL
 161 # include <openssl/aes.h>
 162 #endif
 163 typedef AES_KEY aes_int_key[1];
 164 #define aes_encryption(in,out,int_key)                  \
 165   AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key)
 166 #define aes_key_setup(key,int_key)                      \
 167   AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key)
 168 #else
 169 #include "rijndael.h"
 170 #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6)
 171 typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4];  /* AES internal */
 172 #define aes_encryption(in,out,int_key) \
 173   rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out))
 174 #define aes_key_setup(key,int_key) \
 175   rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \
 176   UMAC_KEY_LEN*8)
 177 #endif
 178
 179 /* The user-supplied UMAC key is stretched using AES in a counter
 180  * mode to supply all random bits needed by UMAC. The kdf function takes
 181  * an AES internal key representation 'key' and writes a stream of
 182  * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct
 183  * 'ndx' causes a distinct byte stream.
 184  */
 185 static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes)
 186 {
 187     UINT8 in_buf[AES_BLOCK_LEN] = {0};
 188     UINT8 out_buf[AES_BLOCK_LEN];
 189     UINT8 *dst_buf = (UINT8 *)bufp;
 190     int i;
 191
 192     /* Setup the initial value */
 193     in_buf[AES_BLOCK_LEN-9] = ndx;
 194     in_buf[AES_BLOCK_LEN-1] = i = 1;
 195
 196     while (nbytes >= AES_BLOCK_LEN) {
 197         aes_encryption(in_buf, out_buf, key);
 198         memcpy(dst_buf,out_buf,AES_BLOCK_LEN);
 199         in_buf[AES_BLOCK_LEN-1] = ++i;
 200         nbytes -= AES_BLOCK_LEN;
 201         dst_buf += AES_BLOCK_LEN;
 202     }
 203     if (nbytes) {
 204         aes_encryption(in_buf, out_buf, key);
 205         memcpy(dst_buf,out_buf,nbytes);
 206     }
 207     explicit_bzero(in_buf, sizeof(in_buf));
 208     explicit_bzero(out_buf, sizeof(out_buf));
 209 }
 210
 211 /* The final UHASH result is XOR'd with the output of a pseudorandom
 212  * function. Here, we use AES to generate random output and
 213  * xor the appropriate bytes depending on the last bits of nonce.
 214  * This scheme is optimized for sequential, increasing big-endian nonces.
 215  */
 216
 217 typedef struct {
 218     UINT8 cache[AES_BLOCK_LEN];  /* Previous AES output is saved      */
 219     UINT8 nonce[AES_BLOCK_LEN];  /* The AES input making above cache  */
 220     aes_int_key prf_key;         /* Expanded AES key for PDF          */
 221 } pdf_ctx;
 222
 223 static void pdf_init(pdf_ctx *pc, aes_int_key prf_key)
 224 {
 225     UINT8 buf[UMAC_KEY_LEN];
 226
 227     kdf(buf, prf_key, 0, UMAC_KEY_LEN);
 228     aes_key_setup(buf, pc->prf_key);
 229
 230     /* Initialize pdf and cache */
 231     memset(pc->nonce, 0, sizeof(pc->nonce));
 232     aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 233     explicit_bzero(buf, sizeof(buf));
 234 }
 235
 236 static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8])
 237 {
 238     /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes
 239      * of the AES output. If last time around we returned the ndx-1st
 240      * element, then we may have the result in the cache already.
 241      */
 242
 243 #if (UMAC_OUTPUT_LEN == 4)
 244 #define LOW_BIT_MASK 3
 245 #elif (UMAC_OUTPUT_LEN == 8)
 246 #define LOW_BIT_MASK 1
 247 #elif (UMAC_OUTPUT_LEN > 8)
 248 #define LOW_BIT_MASK 0
 249 #endif
 250     union {
 251         UINT8 tmp_nonce_lo[4];
 252         UINT32 align;
 253     } t;
 254 #if LOW_BIT_MASK != 0
 255     int ndx = nonce[7] & LOW_BIT_MASK;
 256 #endif
 257     *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1];
 258     t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */
 259
 260     if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) ||
 261          (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) )
 262     {
 263         ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0];
 264         ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0];
 265         aes_encryption(pc->nonce, pc->cache, pc->prf_key);
 266     }
 267
 268 #if (UMAC_OUTPUT_LEN == 4)
 269     *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx];
 270 #elif (UMAC_OUTPUT_LEN == 8)
 271     *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx];
 272 #elif (UMAC_OUTPUT_LEN == 12)
 273     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 274     ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2];
 275 #elif (UMAC_OUTPUT_LEN == 16)
 276     ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0];
 277     ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1];
 278 #endif
 279 }
 280
 281 /* ---------------------------------------------------------------------- */
 282 /* ---------------------------------------------------------------------- */
 283 /* ----- Begin NH Hash Section ------------------------------------------ */
 284 /* ---------------------------------------------------------------------- */
 285 /* ---------------------------------------------------------------------- */
 286
 287 /* The NH-based hash functions used in UMAC are described in the UMAC paper
 288  * and specification, both of which can be found at the UMAC website.
 289  * The interface to this implementation has two
 290  * versions, one expects the entire message being hashed to be passed
 291  * in a single buffer and returns the hash result immediately. The second
 292  * allows the message to be passed in a sequence of buffers. In the
 293  * multiple-buffer interface, the client calls the routine nh_update() as
 294  * many times as necessary. When there is no more data to be fed to the
 295  * hash, the client calls nh_final() which calculates the hash output.
 296  * Before beginning another hash calculation the nh_reset() routine
 297  * must be called. The single-buffer routine, nh(), is equivalent to
 298  * the sequence of calls nh_update() and nh_final(); however it is
 299  * optimized and should be preferred whenever the multiple-buffer interface
 300  * is not necessary. When using either interface, it is the client's
 301  * responsibility to pass no more than L1_KEY_LEN bytes per hash result.
 302  *
 303  * The routine nh_init() initializes the nh_ctx data structure and
 304  * must be called once, before any other PDF routine.
 305  */
 306
 307  /* The "nh_aux" routines do the actual NH hashing work. They
 308   * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines
 309   * produce output for all STREAMS NH iterations in one call,
 310   * allowing the parallel implementation of the streams.
 311   */
 312
 313 #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied  */
 314 #define L1_KEY_LEN         1024     /* Internal key bytes                 */
 315 #define L1_KEY_SHIFT         16     /* Toeplitz key shift between streams */
 316 #define L1_PAD_BOUNDARY      32     /* pad message to boundary multiple   */
 317 #define ALLOC_BOUNDARY       16     /* Keep buffers aligned to this       */
 318 #define HASH_BUF_BYTES       64     /* nh_aux_hb buffer multiple          */
 319
 320 typedef struct {
 321     UINT8  nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */
 322     UINT8  data   [HASH_BUF_BYTES];    /* Incoming data buffer           */
 323     int next_data_empty;    /* Bookkeeping variable for data buffer.     */
 324     int bytes_hashed;       /* Bytes (out of L1_KEY_LEN) incorporated.   */
 325     UINT64 state[STREAMS];               /* on-line state     */
 326 } nh_ctx;
 327
 328
 329 #if (UMAC_OUTPUT_LEN == 4)
 330
 331 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 332 /* NH hashing primitive. Previous (partial) hash result is loaded and
 333 * then stored via hp pointer. The length of the data pointed at by "dp",
 334 * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32).  Key
 335 * is expected to be endian compensated in memory at key setup.
 336 */
 337 {
 338     UINT64 h;
 339     UWORD c = dlen / 32;
 340     UINT32 *k = (UINT32 *)kp;
 341     const UINT32 *d = (const UINT32 *)dp;
 342     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 343     UINT32 k0,k1,k2,k3,k4,k5,k6,k7;
 344
 345     h = *((UINT64 *)hp);
 346     do {
 347         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 348         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 349         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 350         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 351         k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 352         k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 353         h += MUL64((k0 + d0), (k4 + d4));
 354         h += MUL64((k1 + d1), (k5 + d5));
 355         h += MUL64((k2 + d2), (k6 + d6));
 356         h += MUL64((k3 + d3), (k7 + d7));
 357
 358         d += 8;
 359         k += 8;
 360     } while (--c);
 361   *((UINT64 *)hp) = h;
 362 }
 363
 364 #elif (UMAC_OUTPUT_LEN == 8)
 365
 366 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 367 /* Same as previous nh_aux, but two streams are handled in one pass,
 368  * reading and writing 16 bytes of hash-state per call.
 369  */
 370 {
 371   UINT64 h1,h2;
 372   UWORD c = dlen / 32;
 373   UINT32 *k = (UINT32 *)kp;
 374   const UINT32 *d = (const UINT32 *)dp;
 375   UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 376   UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 377         k8,k9,k10,k11;
 378
 379   h1 = *((UINT64 *)hp);
 380   h2 = *((UINT64 *)hp + 1);
 381   k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 382   do {
 383     d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 384     d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 385     d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 386     d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 387     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 388     k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 389
 390     h1 += MUL64((k0 + d0), (k4 + d4));
 391     h2 += MUL64((k4 + d0), (k8 + d4));
 392
 393     h1 += MUL64((k1 + d1), (k5 + d5));
 394     h2 += MUL64((k5 + d1), (k9 + d5));
 395
 396     h1 += MUL64((k2 + d2), (k6 + d6));
 397     h2 += MUL64((k6 + d2), (k10 + d6));
 398
 399     h1 += MUL64((k3 + d3), (k7 + d7));
 400     h2 += MUL64((k7 + d3), (k11 + d7));
 401
 402     k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 403
 404     d += 8;
 405     k += 8;
 406   } while (--c);
 407   ((UINT64 *)hp)[0] = h1;
 408   ((UINT64 *)hp)[1] = h2;
 409 }
 410
 411 #elif (UMAC_OUTPUT_LEN == 12)
 412
 413 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 414 /* Same as previous nh_aux, but two streams are handled in one pass,
 415  * reading and writing 24 bytes of hash-state per call.
 416 */
 417 {
 418     UINT64 h1,h2,h3;
 419     UWORD c = dlen / 32;
 420     UINT32 *k = (UINT32 *)kp;
 421     const UINT32 *d = (const UINT32 *)dp;
 422     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 423     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 424         k8,k9,k10,k11,k12,k13,k14,k15;
 425
 426     h1 = *((UINT64 *)hp);
 427     h2 = *((UINT64 *)hp + 1);
 428     h3 = *((UINT64 *)hp + 2);
 429     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 430     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 431     do {
 432         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 433         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 434         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 435         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 436         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 437         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 438
 439         h1 += MUL64((k0 + d0), (k4 + d4));
 440         h2 += MUL64((k4 + d0), (k8 + d4));
 441         h3 += MUL64((k8 + d0), (k12 + d4));
 442
 443         h1 += MUL64((k1 + d1), (k5 + d5));
 444         h2 += MUL64((k5 + d1), (k9 + d5));
 445         h3 += MUL64((k9 + d1), (k13 + d5));
 446
 447         h1 += MUL64((k2 + d2), (k6 + d6));
 448         h2 += MUL64((k6 + d2), (k10 + d6));
 449         h3 += MUL64((k10 + d2), (k14 + d6));
 450
 451         h1 += MUL64((k3 + d3), (k7 + d7));
 452         h2 += MUL64((k7 + d3), (k11 + d7));
 453         h3 += MUL64((k11 + d3), (k15 + d7));
 454
 455         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 456         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 457
 458         d += 8;
 459         k += 8;
 460     } while (--c);
 461     ((UINT64 *)hp)[0] = h1;
 462     ((UINT64 *)hp)[1] = h2;
 463     ((UINT64 *)hp)[2] = h3;
 464 }
 465
 466 #elif (UMAC_OUTPUT_LEN == 16)
 467
 468 static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen)
 469 /* Same as previous nh_aux, but two streams are handled in one pass,
 470  * reading and writing 24 bytes of hash-state per call.
 471 */
 472 {
 473     UINT64 h1,h2,h3,h4;
 474     UWORD c = dlen / 32;
 475     UINT32 *k = (UINT32 *)kp;
 476     const UINT32 *d = (const UINT32 *)dp;
 477     UINT32 d0,d1,d2,d3,d4,d5,d6,d7;
 478     UINT32 k0,k1,k2,k3,k4,k5,k6,k7,
 479         k8,k9,k10,k11,k12,k13,k14,k15,
 480         k16,k17,k18,k19;
 481
 482     h1 = *((UINT64 *)hp);
 483     h2 = *((UINT64 *)hp + 1);
 484     h3 = *((UINT64 *)hp + 2);
 485     h4 = *((UINT64 *)hp + 3);
 486     k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3);
 487     k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7);
 488     do {
 489         d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1);
 490         d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3);
 491         d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5);
 492         d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7);
 493         k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11);
 494         k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15);
 495         k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19);
 496
 497         h1 += MUL64((k0 + d0), (k4 + d4));
 498         h2 += MUL64((k4 + d0), (k8 + d4));
 499         h3 += MUL64((k8 + d0), (k12 + d4));
 500         h4 += MUL64((k12 + d0), (k16 + d4));
 501
 502         h1 += MUL64((k1 + d1), (k5 + d5));
 503         h2 += MUL64((k5 + d1), (k9 + d5));
 504         h3 += MUL64((k9 + d1), (k13 + d5));
 505         h4 += MUL64((k13 + d1), (k17 + d5));
 506
 507         h1 += MUL64((k2 + d2), (k6 + d6));
 508         h2 += MUL64((k6 + d2), (k10 + d6));
 509         h3 += MUL64((k10 + d2), (k14 + d6));
 510         h4 += MUL64((k14 + d2), (k18 + d6));
 511
 512         h1 += MUL64((k3 + d3), (k7 + d7));
 513         h2 += MUL64((k7 + d3), (k11 + d7));
 514         h3 += MUL64((k11 + d3), (k15 + d7));
 515         h4 += MUL64((k15 + d3), (k19 + d7));
 516
 517         k0 = k8; k1 = k9; k2 = k10; k3 = k11;
 518         k4 = k12; k5 = k13; k6 = k14; k7 = k15;
 519         k8 = k16; k9 = k17; k10 = k18; k11 = k19;
 520
 521         d += 8;
 522         k += 8;
 523     } while (--c);
 524     ((UINT64 *)hp)[0] = h1;
 525     ((UINT64 *)hp)[1] = h2;
 526     ((UINT64 *)hp)[2] = h3;
 527     ((UINT64 *)hp)[3] = h4;
 528 }
 529
 530 /* ---------------------------------------------------------------------- */
 531 #endif  /* UMAC_OUTPUT_LENGTH */
 532 /* ---------------------------------------------------------------------- */
 533
 534
 535 /* ---------------------------------------------------------------------- */
 536
 537 static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
 538 /* This function is a wrapper for the primitive NH hash functions. It takes
 539  * as argument "hc" the current hash context and a buffer which must be a
 540  * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset
 541  * appropriately according to how much message has been hashed already.
 542  */
 543 {
 544     UINT8 *key;
 545
 546     key = hc->nh_key + hc->bytes_hashed;
 547     nh_aux(key, buf, hc->state, nbytes);
 548 }
 549
 550 /* ---------------------------------------------------------------------- */
 551
 552 #if (__LITTLE_ENDIAN__)
 553 static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes)
 554 /* We endian convert the keys on little-endian computers to               */
 555 /* compensate for the lack of big-endian memory reads during hashing.     */
 556 {
 557     UWORD iters = num_bytes / bpw;
 558     if (bpw == 4) {
 559         UINT32 *p = (UINT32 *)buf;
 560         do {
 561             *p = LOAD_UINT32_REVERSED(p);
 562             p++;
 563         } while (--iters);
 564     } else if (bpw == 8) {
 565         UINT32 *p = (UINT32 *)buf;
 566         UINT32 t;
 567         do {
 568             t = LOAD_UINT32_REVERSED(p+1);
 569             p[1] = LOAD_UINT32_REVERSED(p);
 570             p[0] = t;
 571             p += 2;
 572         } while (--iters);
 573     }
 574 }
 575 #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z))
 576 #else
 577 #define endian_convert_if_le(x,y,z) do{}while(0)  /* Do nothing */
 578 #endif
 579
 580 /* ---------------------------------------------------------------------- */
 581
 582 static void nh_reset(nh_ctx *hc)
 583 /* Reset nh_ctx to ready for hashing of new data */
 584 {
 585     hc->bytes_hashed = 0;
 586     hc->next_data_empty = 0;
 587     hc->state[0] = 0;
 588 #if (UMAC_OUTPUT_LEN >= 8)
 589     hc->state[1] = 0;
 590 #endif
 591 #if (UMAC_OUTPUT_LEN >= 12)
 592     hc->state[2] = 0;
 593 #endif
 594 #if (UMAC_OUTPUT_LEN == 16)
 595     hc->state[3] = 0;
 596 #endif
 597
 598 }
 599
 600 /* ---------------------------------------------------------------------- */
 601
 602 static void nh_init(nh_ctx *hc, aes_int_key prf_key)
 603 /* Generate nh_key, endian convert and reset to be ready for hashing.   */
 604 {
 605     kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key));
 606     endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key));
 607     nh_reset(hc);
 608 }
 609
 610 /* ---------------------------------------------------------------------- */
 611
 612 static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes)
 613 /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an    */
 614 /* even multiple of HASH_BUF_BYTES.                                       */
 615 {
 616     UINT32 i,j;
 617
 618     j = hc->next_data_empty;
 619     if ((j + nbytes) >= HASH_BUF_BYTES) {
 620         if (j) {
 621             i = HASH_BUF_BYTES - j;
 622             memcpy(hc->data+j, buf, i);
 623             nh_transform(hc,hc->data,HASH_BUF_BYTES);
 624             nbytes -= i;
 625             buf += i;
 626             hc->bytes_hashed += HASH_BUF_BYTES;
 627         }
 628         if (nbytes >= HASH_BUF_BYTES) {
 629             i = nbytes & ~(HASH_BUF_BYTES - 1);
 630             nh_transform(hc, buf, i);
 631             nbytes -= i;
 632             buf += i;
 633             hc->bytes_hashed += i;
 634         }
 635         j = 0;
 636     }
 637     memcpy(hc->data + j, buf, nbytes);
 638     hc->next_data_empty = j + nbytes;
 639 }
 640
 641 /* ---------------------------------------------------------------------- */
 642
 643 static void zero_pad(UINT8 *p, int nbytes)
 644 {
 645 /* Write "nbytes" of zeroes, beginning at "p" */
 646     if (nbytes >= (int)sizeof(UWORD)) {
 647         while ((ptrdiff_t)p % sizeof(UWORD)) {
 648             *p = 0;
 649             nbytes--;
 650             p++;
 651         }
 652         while (nbytes >= (int)sizeof(UWORD)) {
 653             *(UWORD *)p = 0;
 654             nbytes -= sizeof(UWORD);
 655             p += sizeof(UWORD);
 656         }
 657     }
 658     while (nbytes) {
 659         *p = 0;
 660         nbytes--;
 661         p++;
 662     }
 663 }
 664
 665 /* ---------------------------------------------------------------------- */
 666
 667 static void nh_final(nh_ctx *hc, UINT8 *result)
 668 /* After passing some number of data buffers to nh_update() for integration
 669  * into an NH context, nh_final is called to produce a hash result. If any
 670  * bytes are in the buffer hc->data, incorporate them into the
 671  * NH context. Finally, add into the NH accumulation "state" the total number
 672  * of bits hashed. The resulting numbers are written to the buffer "result".
 673  * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated.
 674  */
 675 {
 676     int nh_len, nbits;
 677
 678     if (hc->next_data_empty != 0) {
 679         nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) &
 680                                                 ~(L1_PAD_BOUNDARY - 1));
 681         zero_pad(hc->data + hc->next_data_empty,
 682                                           nh_len - hc->next_data_empty);
 683         nh_transform(hc, hc->data, nh_len);
 684         hc->bytes_hashed += hc->next_data_empty;
 685     } else if (hc->bytes_hashed == 0) {
 686         nh_len = L1_PAD_BOUNDARY;
 687         zero_pad(hc->data, L1_PAD_BOUNDARY);
 688         nh_transform(hc, hc->data, nh_len);
 689     }
 690
 691     nbits = (hc->bytes_hashed << 3);
 692     ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits;
 693 #if (UMAC_OUTPUT_LEN >= 8)
 694     ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits;
 695 #endif
 696 #if (UMAC_OUTPUT_LEN >= 12)
 697     ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits;
 698 #endif
 699 #if (UMAC_OUTPUT_LEN == 16)
 700     ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits;
 701 #endif
 702     nh_reset(hc);
 703 }
 704
 705 /* ---------------------------------------------------------------------- */
 706
 707 static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len,
 708                UINT32 unpadded_len, UINT8 *result)
 709 /* All-in-one nh_update() and nh_final() equivalent.
 710  * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is
 711  * well aligned
 712  */
 713 {
 714     UINT32 nbits;
 715
 716     /* Initialize the hash state */
 717     nbits = (unpadded_len << 3);
 718
 719     ((UINT64 *)result)[0] = nbits;
 720 #if (UMAC_OUTPUT_LEN >= 8)
 721     ((UINT64 *)result)[1] = nbits;
 722 #endif
 723 #if (UMAC_OUTPUT_LEN >= 12)
 724     ((UINT64 *)result)[2] = nbits;
 725 #endif
 726 #if (UMAC_OUTPUT_LEN == 16)
 727     ((UINT64 *)result)[3] = nbits;
 728 #endif
 729
 730     nh_aux(hc->nh_key, buf, result, padded_len);
 731 }
 732
 733 /* ---------------------------------------------------------------------- */
 734 /* ---------------------------------------------------------------------- */
 735 /* ----- Begin UHASH Section -------------------------------------------- */
 736 /* ---------------------------------------------------------------------- */
 737 /* ---------------------------------------------------------------------- */
 738
 739 /* UHASH is a multi-layered algorithm. Data presented to UHASH is first
 740  * hashed by NH. The NH output is then hashed by a polynomial-hash layer
 741  * unless the initial data to be hashed is short. After the polynomial-
 742  * layer, an inner-product hash is used to produce the final UHASH output.
 743  *
 744  * UHASH provides two interfaces, one all-at-once and another where data
 745  * buffers are presented sequentially. In the sequential interface, the
 746  * UHASH client calls the routine uhash_update() as many times as necessary.
 747  * When there is no more data to be fed to UHASH, the client calls
 748  * uhash_final() which
 749  * calculates the UHASH output. Before beginning another UHASH calculation
 750  * the uhash_reset() routine must be called. The all-at-once UHASH routine,
 751  * uhash(), is equivalent to the sequence of calls uhash_update() and
 752  * uhash_final(); however it is optimized and should be
 753  * used whenever the sequential interface is not necessary.
 754  *
 755  * The routine uhash_init() initializes the uhash_ctx data structure and
 756  * must be called once, before any other UHASH routine.
 757  */
 758
 759 /* ---------------------------------------------------------------------- */
 760 /* ----- Constants and uhash_ctx ---------------------------------------- */
 761 /* ---------------------------------------------------------------------- */
 762
 763 /* ---------------------------------------------------------------------- */
 764 /* ----- Poly hash and Inner-Product hash Constants --------------------- */
 765 /* ---------------------------------------------------------------------- */
 766
 767 /* Primes and masks */
 768 #define p36    ((UINT64)0x0000000FFFFFFFFBull)              /* 2^36 -  5 */
 769 #define p64    ((UINT64)0xFFFFFFFFFFFFFFC5ull)              /* 2^64 - 59 */
 770 #define m36    ((UINT64)0x0000000FFFFFFFFFull)  /* The low 36 of 64 bits */
 771
 772
 773 /* ---------------------------------------------------------------------- */
 774
 775 typedef struct uhash_ctx {
 776     nh_ctx hash;                          /* Hash context for L1 NH hash  */
 777     UINT64 poly_key_8[STREAMS];           /* p64 poly keys                */
 778     UINT64 poly_accum[STREAMS];           /* poly hash result             */
 779     UINT64 ip_keys[STREAMS*4];            /* Inner-product keys           */
 780     UINT32 ip_trans[STREAMS];             /* Inner-product translation    */
 781     UINT32 msg_len;                       /* Total length of data passed  */
 782                                           /* to uhash */
 783 } uhash_ctx;
 784 typedef struct uhash_ctx *uhash_ctx_t;
 785
 786 /* ---------------------------------------------------------------------- */
 787
 788
 789 /* The polynomial hashes use Horner's rule to evaluate a polynomial one
 790  * word at a time. As described in the specification, poly32 and poly64
 791  * require keys from special domains. The following implementations exploit
 792  * the special domains to avoid overflow. The results are not guaranteed to
 793  * be within Z_p32 and Z_p64, but the Inner-Product hash implementation
 794  * patches any errant values.
 795  */
 796
 797 static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data)
 798 {
 799     UINT32 key_hi = (UINT32)(key >> 32),
 800            key_lo = (UINT32)key,
 801            cur_hi = (UINT32)(cur >> 32),
 802            cur_lo = (UINT32)cur,
 803            x_lo,
 804            x_hi;
 805     UINT64 X,T,res;
 806
 807     X =  MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo);
 808     x_lo = (UINT32)X;
 809     x_hi = (UINT32)(X >> 32);
 810
 811     res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo);
 812
 813     T = ((UINT64)x_lo << 32);
 814     res += T;
 815     if (res < T)
 816         res += 59;
 817
 818     res += data;
 819     if (res < data)
 820         res += 59;
 821
 822     return res;
 823 }
 824
 825
 826 /* Although UMAC is specified to use a ramped polynomial hash scheme, this
 827  * implementation does not handle all ramp levels. Because we don't handle
 828  * the ramp up to p128 modulus in this implementation, we are limited to
 829  * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24
 830  * bytes input to UMAC per tag, ie. 16MB).
 831  */
 832 static void poly_hash(uhash_ctx_t hc, UINT32 data_in[])
 833 {
 834     int i;
 835     UINT64 *data=(UINT64*)data_in;
 836
 837     for (i = 0; i < STREAMS; i++) {
 838         if ((UINT32)(data[i] >> 32) == 0xfffffffful) {
 839             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 840                                        hc->poly_key_8[i], p64 - 1);
 841             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 842                                        hc->poly_key_8[i], (data[i] - 59));
 843         } else {
 844             hc->poly_accum[i] = poly64(hc->poly_accum[i],
 845                                        hc->poly_key_8[i], data[i]);
 846         }
 847     }
 848 }
 849
 850
 851 /* ---------------------------------------------------------------------- */
 852
 853
 854 /* The final step in UHASH is an inner-product hash. The poly hash
 855  * produces a result not necessarily WORD_LEN bytes long. The inner-
 856  * product hash breaks the polyhash output into 16-bit chunks and
 857  * multiplies each with a 36 bit key.
 858  */
 859
 860 static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data)
 861 {
 862     t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48);
 863     t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32);
 864     t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16);
 865     t = t + ipkp[3] * (UINT64)(UINT16)(data);
 866
 867     return t;
 868 }
 869
 870 static UINT32 ip_reduce_p36(UINT64 t)
 871 {
 872 /* Divisionless modular reduction */
 873     UINT64 ret;
 874
 875     ret = (t & m36) + 5 * (t >> 36);
 876     if (ret >= p36)
 877         ret -= p36;
 878
 879     /* return least significant 32 bits */
 880     return (UINT32)(ret);
 881 }
 882
 883
 884 /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then
 885  * the polyhash stage is skipped and ip_short is applied directly to the
 886  * NH output.
 887  */
 888 static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res)
 889 {
 890     UINT64 t;
 891     UINT64 *nhp = (UINT64 *)nh_res;
 892
 893     t  = ip_aux(0,ahc->ip_keys, nhp[0]);
 894     STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]);
 895 #if (UMAC_OUTPUT_LEN >= 8)
 896     t  = ip_aux(0,ahc->ip_keys+4, nhp[1]);
 897     STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]);
 898 #endif
 899 #if (UMAC_OUTPUT_LEN >= 12)
 900     t  = ip_aux(0,ahc->ip_keys+8, nhp[2]);
 901     STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]);
 902 #endif
 903 #if (UMAC_OUTPUT_LEN == 16)
 904     t  = ip_aux(0,ahc->ip_keys+12, nhp[3]);
 905     STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]);
 906 #endif
 907 }
 908
 909 /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then
 910  * the polyhash stage is not skipped and ip_long is applied to the
 911  * polyhash output.
 912  */
 913 static void ip_long(uhash_ctx_t ahc, u_char *res)
 914 {
 915     int i;
 916     UINT64 t;
 917
 918     for (i = 0; i < STREAMS; i++) {
 919         /* fix polyhash output not in Z_p64 */
 920         if (ahc->poly_accum[i] >= p64)
 921             ahc->poly_accum[i] -= p64;
 922         t  = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]);
 923         STORE_UINT32_BIG((UINT32 *)res+i,
 924                          ip_reduce_p36(t) ^ ahc->ip_trans[i]);
 925     }
 926 }
 927
 928
 929 /* ---------------------------------------------------------------------- */
 930
 931 /* ---------------------------------------------------------------------- */
 932
 933 /* Reset uhash context for next hash session */
 934 static int uhash_reset(uhash_ctx_t pc)
 935 {
 936     nh_reset(&pc->hash);
 937     pc->msg_len = 0;
 938     pc->poly_accum[0] = 1;
 939 #if (UMAC_OUTPUT_LEN >= 8)
 940     pc->poly_accum[1] = 1;
 941 #endif
 942 #if (UMAC_OUTPUT_LEN >= 12)
 943     pc->poly_accum[2] = 1;
 944 #endif
 945 #if (UMAC_OUTPUT_LEN == 16)
 946     pc->poly_accum[3] = 1;
 947 #endif
 948     return 1;
 949 }
 950
 951 /* ---------------------------------------------------------------------- */
 952
 953 /* Given a pointer to the internal key needed by kdf() and a uhash context,
 954  * initialize the NH context and generate keys needed for poly and inner-
 955  * product hashing. All keys are endian adjusted in memory so that native
 956  * loads cause correct keys to be in registers during calculation.
 957  */
 958 static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key)
 959 {
 960     int i;
 961     UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)];
 962
 963     /* Zero the entire uhash context */
 964     memset(ahc, 0, sizeof(uhash_ctx));
 965
 966     /* Initialize the L1 hash */
 967     nh_init(&ahc->hash, prf_key);
 968
 969     /* Setup L2 hash variables */
 970     kdf(buf, prf_key, 2, sizeof(buf));    /* Fill buffer with index 1 key */
 971     for (i = 0; i < STREAMS; i++) {
 972         /* Fill keys from the buffer, skipping bytes in the buffer not
 973          * used by this implementation. Endian reverse the keys if on a
 974          * little-endian computer.
 975          */
 976         memcpy(ahc->poly_key_8+i, buf+24*i, 8);
 977         endian_convert_if_le(ahc->poly_key_8+i, 8, 8);
 978         /* Mask the 64-bit keys to their special domain */
 979         ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu;
 980         ahc->poly_accum[i] = 1;  /* Our polyhash prepends a non-zero word */
 981     }
 982
 983     /* Setup L3-1 hash variables */
 984     kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */
 985     for (i = 0; i < STREAMS; i++)
 986           memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64),
 987                                                  4*sizeof(UINT64));
 988     endian_convert_if_le(ahc->ip_keys, sizeof(UINT64),
 989                                                   sizeof(ahc->ip_keys));
 990     for (i = 0; i < STREAMS*4; i++)
 991         ahc->ip_keys[i] %= p36;  /* Bring into Z_p36 */
 992
 993     /* Setup L3-2 hash variables    */
 994     /* Fill buffer with index 4 key */
 995     kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32));
 996     endian_convert_if_le(ahc->ip_trans, sizeof(UINT32),
 997                          STREAMS * sizeof(UINT32));
 998     explicit_bzero(buf, sizeof(buf));
 999 }
1000
1001 /* ---------------------------------------------------------------------- */
1002
1003 #if 0
1004 static uhash_ctx_t uhash_alloc(u_char key[])
1005 {
1006 /* Allocate memory and force to a 16-byte boundary. */
1007     uhash_ctx_t ctx;
1008     u_char bytes_to_add;
1009     aes_int_key prf_key;
1010
1011     ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY);
1012     if (ctx) {
1013         if (ALLOC_BOUNDARY) {
1014             bytes_to_add = ALLOC_BOUNDARY -
1015                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1));
1016             ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add);
1017             *((u_char *)ctx - 1) = bytes_to_add;
1018         }
1019         aes_key_setup(key,prf_key);
1020         uhash_init(ctx, prf_key);
1021     }
1022     return (ctx);
1023 }
1024 #endif
1025
1026 /* ---------------------------------------------------------------------- */
1027
1028 #if 0
1029 static int uhash_free(uhash_ctx_t ctx)
1030 {
1031 /* Free memory allocated by uhash_alloc */
1032     u_char bytes_to_sub;
1033
1034     if (ctx) {
1035         if (ALLOC_BOUNDARY) {
1036             bytes_to_sub = *((u_char *)ctx - 1);
1037             ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub);
1038         }
1039         free(ctx);
1040     }
1041     return (1);
1042 }
1043 #endif
1044 /* ---------------------------------------------------------------------- */
1045
1046 static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len)
1047 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and
1048  * hash each one with NH, calling the polyhash on each NH output.
1049  */
1050 {
1051     UWORD bytes_hashed, bytes_remaining;
1052     UINT64 result_buf[STREAMS];
1053     UINT8 *nh_result = (UINT8 *)&result_buf;
1054
1055     if (ctx->msg_len + len <= L1_KEY_LEN) {
1056         nh_update(&ctx->hash, (const UINT8 *)input, len);
1057         ctx->msg_len += len;
1058     } else {
1059
1060          bytes_hashed = ctx->msg_len % L1_KEY_LEN;
1061          if (ctx->msg_len == L1_KEY_LEN)
1062              bytes_hashed = L1_KEY_LEN;
1063
1064          if (bytes_hashed + len >= L1_KEY_LEN) {
1065
1066              /* If some bytes have been passed to the hash function      */
1067              /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */
1068              /* bytes to complete the current nh_block.                  */
1069              if (bytes_hashed) {
1070                  bytes_remaining = (L1_KEY_LEN - bytes_hashed);
1071                  nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining);
1072                  nh_final(&ctx->hash, nh_result);
1073                  ctx->msg_len += bytes_remaining;
1074                  poly_hash(ctx,(UINT32 *)nh_result);
1075                  len -= bytes_remaining;
1076                  input += bytes_remaining;
1077              }
1078
1079              /* Hash directly from input stream if enough bytes */
1080              while (len >= L1_KEY_LEN) {
1081                  nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN,
1082                                    L1_KEY_LEN, nh_result);
1083                  ctx->msg_len += L1_KEY_LEN;
1084                  len -= L1_KEY_LEN;
1085                  input += L1_KEY_LEN;
1086                  poly_hash(ctx,(UINT32 *)nh_result);
1087              }
1088          }
1089
1090          /* pass remaining < L1_KEY_LEN bytes of input data to NH */
1091          if (len) {
1092              nh_update(&ctx->hash, (const UINT8 *)input, len);
1093              ctx->msg_len += len;
1094          }
1095      }
1096
1097     return (1);
1098 }
1099
1100 /* ---------------------------------------------------------------------- */
1101
1102 static int uhash_final(uhash_ctx_t ctx, u_char *res)
1103 /* Incorporate any pending data, pad, and generate tag */
1104 {
1105     UINT64 result_buf[STREAMS];
1106     UINT8 *nh_result = (UINT8 *)&result_buf;
1107
1108     if (ctx->msg_len > L1_KEY_LEN) {
1109         if (ctx->msg_len % L1_KEY_LEN) {
1110             nh_final(&ctx->hash, nh_result);
1111             poly_hash(ctx,(UINT32 *)nh_result);
1112         }
1113         ip_long(ctx, res);
1114     } else {
1115         nh_final(&ctx->hash, nh_result);
1116         ip_short(ctx,nh_result, res);
1117     }
1118     uhash_reset(ctx);
1119     return (1);
1120 }
1121
1122 /* ---------------------------------------------------------------------- */
1123
1124 #if 0
1125 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res)
1126 /* assumes that msg is in a writable buffer of length divisible by */
1127 /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed.           */
1128 {
1129     UINT8 nh_result[STREAMS*sizeof(UINT64)];
1130     UINT32 nh_len;
1131     int extra_zeroes_needed;
1132
1133     /* If the message to be hashed is no longer than L1_HASH_LEN, we skip
1134      * the polyhash.
1135      */
1136     if (len <= L1_KEY_LEN) {
1137         if (len == 0)                  /* If zero length messages will not */
1138                 nh_len = L1_PAD_BOUNDARY;  /* be seen, comment out this case   */
1139         else
1140                 nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1141         extra_zeroes_needed = nh_len - len;
1142         zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1143         nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1144         ip_short(ahc,nh_result, res);
1145     } else {
1146         /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH
1147          * output to poly_hash().
1148          */
1149         do {
1150             nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result);
1151             poly_hash(ahc,(UINT32 *)nh_result);
1152             len -= L1_KEY_LEN;
1153             msg += L1_KEY_LEN;
1154         } while (len >= L1_KEY_LEN);
1155         if (len) {
1156             nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1));
1157             extra_zeroes_needed = nh_len - len;
1158             zero_pad((UINT8 *)msg + len, extra_zeroes_needed);
1159             nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result);
1160             poly_hash(ahc,(UINT32 *)nh_result);
1161         }
1162
1163         ip_long(ahc, res);
1164     }
1165
1166     uhash_reset(ahc);
1167     return 1;
1168 }
1169 #endif
1170
1171 /* ---------------------------------------------------------------------- */
1172 /* ---------------------------------------------------------------------- */
1173 /* ----- Begin UMAC Section --------------------------------------------- */
1174 /* ---------------------------------------------------------------------- */
1175 /* ---------------------------------------------------------------------- */
1176
1177 /* The UMAC interface has two interfaces, an all-at-once interface where
1178  * the entire message to be authenticated is passed to UMAC in one buffer,
1179  * and a sequential interface where the message is presented a little at a
1180  * time. The all-at-once is more optimized than the sequential version and
1181  * should be preferred when the sequential interface is not required.
1182  */
1183 struct umac_ctx {
1184     uhash_ctx hash;          /* Hash function for message compression    */
1185     pdf_ctx pdf;             /* PDF for hashed output                    */
1186     void *free_ptr;          /* Address to free this struct via          */
1187 } umac_ctx;
1188
1189 /* ---------------------------------------------------------------------- */
1190
1191 #if 0
1192 int umac_reset(struct umac_ctx *ctx)
1193 /* Reset the hash function to begin a new authentication.        */
1194 {
1195     uhash_reset(&ctx->hash);
1196     return (1);
1197 }
1198 #endif
1199
1200 /* ---------------------------------------------------------------------- */
1201
1202 int umac_delete(struct umac_ctx *ctx)
1203 /* Deallocate the ctx structure */
1204 {
1205     if (ctx) {
1206         if (ALLOC_BOUNDARY)
1207             ctx = (struct umac_ctx *)ctx->free_ptr;
1208         freezero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY);
1209     }
1210     return (1);
1211 }
1212
1213 /* ---------------------------------------------------------------------- */
1214
1215 struct umac_ctx *umac_new(const u_char key[])
1216 /* Dynamically allocate a umac_ctx struct, initialize variables,
1217  * generate subkeys from key. Align to 16-byte boundary.
1218  */
1219 {
1220     struct umac_ctx *ctx, *octx;
1221     size_t bytes_to_add;
1222     aes_int_key prf_key;
1223
1224     octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY);
1225     if (ctx) {
1226         if (ALLOC_BOUNDARY) {
1227             bytes_to_add = ALLOC_BOUNDARY -
1228                               ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1));
1229             ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add);
1230         }
1231         ctx->free_ptr = octx;
1232         aes_key_setup(key, prf_key);
1233         pdf_init(&ctx->pdf, prf_key);
1234         uhash_init(&ctx->hash, prf_key);
1235         explicit_bzero(prf_key, sizeof(prf_key));
1236     }
1237
1238     return (ctx);
1239 }
1240
1241 /* ---------------------------------------------------------------------- */
1242
1243 int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8])
1244 /* Incorporate any pending data, pad, and generate tag */
1245 {
1246     uhash_final(&ctx->hash, (u_char *)tag);
1247     pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag);
1248
1249     return (1);
1250 }
1251
1252 /* ---------------------------------------------------------------------- */
1253
1254 int umac_update(struct umac_ctx *ctx, const u_char *input, long len)
1255 /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and   */
1256 /* hash each one, calling the PDF on the hashed output whenever the hash- */
1257 /* output buffer is full.                                                 */
1258 {
1259     uhash_update(&ctx->hash, input, len);
1260     return (1);
1261 }
1262
1263 /* ---------------------------------------------------------------------- */
1264
1265 #if 0
1266 int umac(struct umac_ctx *ctx, u_char *input,
1267          long len, u_char tag[],
1268          u_char nonce[8])
1269 /* All-in-one version simply calls umac_update() and umac_final().        */
1270 {
1271     uhash(&ctx->hash, input, len, (u_char *)tag);
1272     pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag);
1273
1274     return (1);
1275 }
1276 #endif
1277
1278 /* ---------------------------------------------------------------------- */
1279 /* ---------------------------------------------------------------------- */
1280 /* ----- End UMAC Section ----------------------------------------------- */
1281 /* ---------------------------------------------------------------------- */
1282 /* ---------------------------------------------------------------------- */