11848 Remove STRUIO_IP support from ip_cksum.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25 /* Copyright (c) 1990 Mentat Inc. */



  26 
  27 #include <sys/types.h>
  28 #include <sys/inttypes.h>
  29 #include <sys/systm.h>
  30 #include <sys/stream.h>
  31 #include <sys/strsun.h>

  32 #include <sys/debug.h>
  33 #include <sys/ddi.h>
  34 #include <sys/vtrace.h>
  35 #include <inet/sctp_crc32.h>
  36 #include <inet/ip.h>
  37 
  38 #include <sys/multidata.h>
  39 #include <sys/multidata_impl.h>
  40 
  41 extern unsigned int     ip_ocsum(ushort_t *address, int halfword_count,
  42     unsigned int sum);
  43 
  44 /*
  45  * Checksum routine for Internet Protocol family headers.
  46  * This routine is very heavily used in the network
  47  * code and should be modified for each CPU to be as fast as possible.
  48  */
  49 
  50 #define mp_len(mp) ((mp)->b_wptr - (mp)->b_rptr)
  51 
  52 /*
  53  * Even/Odd checks. Usually it is performed on pointers but may be
  54  * used on integers as well. uintptr_t is long enough to hold both
  55  * integer and pointer.
  56  */
  57 #define is_odd(p) (((uintptr_t)(p) & 0x1) != 0)
  58 #define is_even(p) (!is_odd(p))
  59 
  60 
  61 #ifdef ZC_TEST
  62 /*
  63  * Disable the TCP s/w cksum.
  64  * XXX - This is just a hack for testing purpose. Don't use it for
  65  * anything else!
  66  */
  67 int noswcksum = 0;





  68 #endif

  69 /*







  70  * Note: this does not ones-complement the result since it is used
  71  * when computing partial checksums.
  72  * For nonSTRUIO_IP mblks, assumes mp->b_rptr+offset is 16 bit aligned.
  73  * For STRUIO_IP mblks, assumes mp->b_datap->db_struiobase is 16 bit aligned.
  74  *
  75  * Note: for STRUIO_IP special mblks some data may have been previously
  76  *       checksumed, this routine will handle additional data prefixed within
  77  *       an mblk or b_cont (chained) mblk(s). This routine will also handle
  78  *       suffixed b_cont mblk(s) and data suffixed within an mblk.
  79  */
  80 unsigned int
  81 ip_cksum(mblk_t *mp, int offset, uint_t sum)
  82 {
  83         ushort_t *w;
  84         ssize_t mlen;
  85         int pmlen;
  86         mblk_t *pmp;
  87         dblk_t *dp = mp->b_datap;
  88         ushort_t psum = 0;
  89 
  90 #ifdef ZC_TEST
  91         if (noswcksum)
  92                 return (0xffff);
  93 #endif
  94         ASSERT(dp);
  95 
  96         if (mp->b_cont == NULL) {
  97                 /*
  98                  * May be fast-path, only one mblk.
  99                  */
 100                 w = (ushort_t *)(mp->b_rptr + offset);
 101                 if (dp->db_struioflag & STRUIO_IP) {
 102                         /*
 103                          * Checksum any data not already done by
 104                          * the caller and add in any partial checksum.
 105                          */
 106                         if ((offset > dp->db_cksumstart) ||
 107                             mp->b_wptr != (uchar_t *)(mp->b_rptr +
 108                             dp->db_cksumend)) {
 109                                 /*
 110                                  * Mblk data pointers aren't inclusive
 111                                  * of uio data, so disregard checksum.
 112                                  *
 113                                  * not using all of data in dblk make sure
 114                                  * not use to use the precalculated checksum
 115                                  * in this case.
 116                                  */
 117                                 dp->db_struioflag &= ~STRUIO_IP;
 118                                 goto norm;
 119                         }
 120                         ASSERT(mp->b_wptr == (mp->b_rptr + dp->db_cksumend));
 121                         psum = *(ushort_t *)dp->db_struioun.data;
 122                         if ((mlen = dp->db_cksumstart - offset) < 0)
 123                                 mlen = 0;
 124                         if (is_odd(mlen))
 125                                 goto slow;
 126                         if (mlen && dp->db_cksumstart != dp->db_cksumstuff &&
 127                             dp->db_cksumend != dp->db_cksumstuff) {
 128                                 /*
 129                                  * There is prefix data to do and some uio
 130                                  * data has already been checksumed and there
 131                                  * is more uio data to do, so do the prefix
 132                                  * data first, then do the remainder of the
 133                                  * uio data.
 134                                  */
 135                                 sum = ip_ocsum(w, mlen >> 1, sum);
 136                                 w = (ushort_t *)(mp->b_rptr +
 137                                     dp->db_cksumstuff);
 138                                 if (is_odd(w)) {
 139                                         pmp = mp;
 140                                         goto slow1;









 141                                 }
 142                                 mlen = dp->db_cksumend - dp->db_cksumstuff;
 143                         } else if (dp->db_cksumend != dp->db_cksumstuff) {
 144                                 /*
 145                                  * There may be uio data to do, if there is
 146                                  * prefix data to do then add in all of the
 147                                  * uio data (if any) to do, else just do any
 148                                  * uio data.
 149                                  */
 150                                 if (mlen)
 151                                         mlen += dp->db_cksumend
 152                                             - dp->db_cksumstuff;
 153                                 else {
 154                                         w = (ushort_t *)(mp->b_rptr +
 155                                             dp->db_cksumstuff);
 156                                         if (is_odd(w))
 157                                                 goto slow;
 158                                         mlen = dp->db_cksumend
 159                                             - dp->db_cksumstuff;
 160                                 }
 161                         } else if (mlen == 0)
 162                                 return (psum);
 163 
 164                         if (is_odd(mlen))
 165                                 goto slow;
 166                         sum += psum;
 167                 } else {
 168                         /*
 169                          * Checksum all data not already done by the caller.















 170                          */
 171                 norm:
 172                         mlen = mp->b_wptr - (uchar_t *)w;
 173                         if (is_odd(mlen))
 174                                 goto slow;






 175                 }
 176                 ASSERT(is_even(w));
 177                 ASSERT(is_even(mlen));
 178                 return (ip_ocsum(w, mlen >> 1, sum));
 179         }
 180         if (dp->db_struioflag & STRUIO_IP)
 181                 psum = *(ushort_t *)dp->db_struioun.data;
 182 slow:
 183         pmp = 0;
 184 slow1:
 185         mlen = 0;
 186         pmlen = 0;
 187         for (; ; ) {
 188                 /*
 189                  * Each trip around loop adds in word(s) from one mbuf segment
 190                  * (except for when pmp == mp, then its two partial trips).

 191                  */
 192                 w = (ushort_t *)(mp->b_rptr + offset);
 193                 if (pmp) {

 194                         /*
 195                          * This is the second trip around for this mblk.










 196                          */
 197                         pmp = 0;
 198                         mlen = 0;
 199                         goto douio;
 200                 } else if (dp->db_struioflag & STRUIO_IP) {
 201                         /*
 202                          * Checksum any data not already done by the
 203                          * caller and add in any partial checksum.
 204                          */
 205                         if ((offset > dp->db_cksumstart) ||
 206                             mp->b_wptr != (uchar_t *)(mp->b_rptr +
 207                             dp->db_cksumend)) {
 208                                 /*
 209                                  * Mblk data pointers aren't inclusive
 210                                  * of uio data, so disregard checksum.





 211                                  *
 212                                  * not using all of data in dblk make sure
 213                                  * not use to use the precalculated checksum
 214                                  * in this case.



 215                                  */
 216                                 dp->db_struioflag &= ~STRUIO_IP;
 217                                 goto snorm;
 218                         }
 219                         ASSERT(mp->b_wptr == (mp->b_rptr + dp->db_cksumend));
 220                         if ((mlen = dp->db_cksumstart - offset) < 0)
 221                                 mlen = 0;
 222                         if (mlen && dp->db_cksumstart != dp->db_cksumstuff) {
 223                                 /*
 224                                  * There is prefix data too do and some
 225                                  * uio data has already been checksumed,
 226                                  * so do the prefix data only this trip.
 227                                  */
 228                                 pmp = mp;
 229                         } else {
 230                                 /*
 231                                  * Add in any partial cksum (if any) and
 232                                  * do the remainder of the uio data.
 233                                  */
 234                                 int odd;
 235                         douio:
 236                                 odd = is_odd(dp->db_cksumstuff -
 237                                     dp->db_cksumstart);
 238                                 if (pmlen == -1) {
 239                                         /*
 240                                          * Previous mlen was odd, so swap
 241                                          * the partial checksum bytes.
 242                                          */
 243                                         sum += ((psum << 8) & 0xffff)
 244                                             | (psum >> 8);
 245                                         if (odd)
 246                                                 pmlen = 0;
 247                                 } else {
 248                                         sum += psum;
 249                                         if (odd)
 250                                                 pmlen = -1;
 251                                 }
 252                                 if (dp->db_cksumend != dp->db_cksumstuff) {
 253                                         /*
 254                                          * If prefix data to do and then all
 255                                          * the uio data nees to be checksumed,
 256                                          * else just do any uio data.
 257                                          */
 258                                         if (mlen)
 259                                                 mlen += dp->db_cksumend
 260                                                     - dp->db_cksumstuff;
 261                                         else {
 262                                                 w = (ushort_t *)(mp->b_rptr +
 263                                                     dp->db_cksumstuff);
 264                                                 mlen = dp->db_cksumend -
 265                                                     dp->db_cksumstuff;
 266                                         }
 267                                 }
 268                         }
 269                 } else {
 270                         /*
 271                          * Checksum all of the mblk data.
 272                          */
 273                 snorm:
 274                         mlen = mp->b_wptr - (uchar_t *)w;
 275                 }
 276 

 277                 mp = mp->b_cont;
 278                 if (mlen > 0 && pmlen == -1) {
 279                         /*
 280                          * There is a byte left from the last
 281                          * segment; add it into the checksum.
 282                          * Don't have to worry about a carry-
 283                          * out here because we make sure that
 284                          * high part of (32 bit) sum is small
 285                          * below.
 286                          */
 287 #ifdef _LITTLE_ENDIAN
 288                         sum += *(uchar_t *)w << 8;
 289 #else
 290                         sum += *(uchar_t *)w;
 291 #endif
 292                         w = (ushort_t *)((char *)w + 1);
 293                         mlen--;
 294                         pmlen = 0;
 295                 }
 296                 if (mlen > 0) {
 297                         if (is_even(w)) {
 298                                 sum = ip_ocsum(w, mlen>>1, sum);
 299                                 w += mlen>>1;
 300                                 /*
 301                                  * If we had an odd number of bytes,
 302                                  * then the last byte goes in the high
 303                                  * part of the sum, and we take the
 304                                  * first byte to the low part of the sum
 305                                  * the next time around the loop.

 306                                  */
 307                                 if (is_odd(mlen)) {
 308 #ifdef _LITTLE_ENDIAN
 309                                         sum += *(uchar_t *)w;
 310 #else
 311                                         sum += *(uchar_t *)w << 8;
 312 #endif
 313                                         pmlen = -1;
 314                                 }
 315                         } else {
 316                                 ushort_t swsum;
 317 #ifdef _LITTLE_ENDIAN
 318                                 sum += *(uchar_t *)w;
 319 #else
 320                                 sum += *(uchar_t *)w << 8;
 321 #endif
 322                                 mlen--;
 323                                 w = (ushort_t *)(1 + (uintptr_t)w);
 324 
 325                                 /* Do a separate checksum and copy operation */
 326                                 swsum = ip_ocsum(w, mlen>>1, 0);
 327                                 sum += ((swsum << 8) & 0xffff) | (swsum >> 8);
 328                                 w += mlen>>1;
 329                                 /*
 330                                  * If we had an even number of bytes,
 331                                  * then the last byte goes in the low
 332                                  * part of the sum.  Otherwise we had an
 333                                  * odd number of bytes and we take the first
 334                                  * byte to the low part of the sum the
 335                                  * next time around the loop.
 336                                  */
 337                                 if (is_odd(mlen)) {
 338 #ifdef _LITTLE_ENDIAN
 339                                         sum += *(uchar_t *)w << 8;
 340 #else
 341                                         sum += *(uchar_t *)w;
 342 #endif
 343                                 }
 344                                 else
 345                                         pmlen = -1;
 346                         }
 347                 }
 348                 /*
 349                  * Locate the next block with some data.
 350                  * If there is a word split across a boundary we
 351                  * will wrap to the top with mlen == -1 and
 352                  * then add it in shifted appropriately.
 353                  */
 354                 offset = 0;
 355                 if (! pmp) {
 356                         for (; ; ) {
 357                                 if (mp == 0) {
 358                                         goto done;
 359                                 }
 360                                 if (mp_len(mp))
 361                                         break;
 362                                 mp = mp->b_cont;
 363                         }
 364                         dp = mp->b_datap;
 365                         if (dp->db_struioflag & STRUIO_IP)
 366                                 psum = *(ushort_t *)dp->db_struioun.data;
 367                 } else
 368                         mp = pmp;
 369         }
 370 done:
 371         /*
 372          * Add together high and low parts of sum
 373          * and carry to get cksum.
 374          * Have to be careful to not drop the last
 375          * carry here.
 376          */
 377         sum = (sum & 0xFFFF) + (sum >> 16);
 378         sum = (sum & 0xFFFF) + (sum >> 16);
 379         TRACE_3(TR_FAC_IP, TR_IP_CKSUM_END,
 380             "ip_cksum_end:(%S) type %d (%X)", "ip_cksum", 1, sum);
 381         return (sum);
 382 }
 383 
 384 uint32_t
 385 sctp_cksum(mblk_t *mp, int offset)
 386 {
 387         uint32_t crc32;
 388         uchar_t *p = NULL;
 389 
 390         crc32 = 0xFFFFFFFF;
 391         p = mp->b_rptr + offset;
 392         crc32 = sctp_crc32(crc32, p, mp->b_wptr - p);
 393         for (mp = mp->b_cont; mp != NULL; mp = mp->b_cont) {
 394                 crc32 = sctp_crc32(crc32, mp->b_rptr, MBLKL(mp));
 395         }
 396 
 397         /* Complement the result */
 398         crc32 = ~crc32;
 399 
 400         return (crc32);
 401 }
 402 
 403 /*
 404  * Routine to compute Internet checksum (16-bit 1's complement) of a given
 405  * Multidata packet descriptor.  As in the non-Multidata routine, this doesn't
 406  * 1's complement the result, such that it may be used to compute partial
 407  * checksums.  Since it works on buffer spans rather than mblks, this routine
 408  * does not handle existing partial checksum value as in the STRUIO_IP special
 409  * mblk case (supporting this is rather trivial, but is perhaps of no use at
 410  * the moment unless synchronous streams and delayed checksum calculation are
 411  * revived.)
 412  *
 413  * Note also here that the given Multidata packet descriptor must refer to
 414  * a header buffer, i.e. it must have a header fragment.  In addition, the
 415  * offset must lie within the boundary of the header fragment.  For the
 416  * outbound tcp (MDT) case, this will not be an issue because the stack
 417  * ensures that such conditions are met, and that there is no need whatsoever
 418  * to compute partial checksums on an arbitrary offset that is not part of
 419  * the header fragment.  We may need to revisit this routine to handle all
 420  * cases of the inbound (MDR) case, especially when we need to perform partial
 421  * checksum calculation due to padded bytes (non-zeroes) in the frame.
 422  */
 423 uint_t
 424 ip_md_cksum(pdesc_t *pd, int offset, uint_t sum)
 425 {
 426         pdescinfo_t     *pdi = &pd->pd_pdi;
 427         uchar_t         *reg_start, *reg_end;
 428         ssize_t         mlen, i;
 429         ushort_t        *w;
 430         boolean_t       byteleft = B_FALSE;
 431 
 432         ASSERT((pdi->flags & PDESC_HAS_REF) != 0);
 433         ASSERT(pdi->hdr_rptr != NULL && pdi->hdr_wptr != NULL);
 434         ASSERT(offset <= PDESC_HDRL(pdi));
 435 
 436         for (i = 0; i < pdi->pld_cnt + 1; i++) {
 437                 if (i == 0) {
 438                         reg_start = pdi->hdr_rptr;
 439                         reg_end = pdi->hdr_wptr;
 440                 } else {
 441                         reg_start = pdi->pld_ary[i - 1].pld_rptr;
 442                         reg_end = pdi->pld_ary[i - 1].pld_wptr;
 443                         offset = 0;
 444                 }
 445 
 446                 w = (ushort_t *)(reg_start + offset);
 447                 mlen = reg_end - (uchar_t *)w;
 448 
 449                 if (mlen > 0 && byteleft) {
 450                         /*
 451                          * There is a byte left from the last
 452                          * segment; add it into the checksum.
 453                          * Don't have to worry about a carry-
 454                          * out here because we make sure that
 455                          * high part of (32 bit) sum is small
 456                          * below.
 457                          */
 458 #ifdef _LITTLE_ENDIAN
 459                         sum += *(uchar_t *)w << 8;
 460 #else
 461                         sum += *(uchar_t *)w;
 462 #endif
 463                         w = (ushort_t *)((char *)w + 1);
 464                         mlen--;
 465                         byteleft = B_FALSE;
 466                 }
 467 
 468                 if (mlen == 0)
 469                         continue;
 470 
 471                 if (is_even(w)) {
 472                         sum = ip_ocsum(w, mlen >> 1, sum);
 473                         w += mlen >> 1;
 474                         /*
 475                          * If we had an odd number of bytes,
 476                          * then the last byte goes in the high
 477                          * part of the sum, and we take the
 478                          * first byte to the low part of the sum
 479                          * the next time around the loop.
 480                          */
 481                         if (is_odd(mlen)) {
 482 #ifdef _LITTLE_ENDIAN
 483                                 sum += *(uchar_t *)w;
 484 #else
 485                                 sum += *(uchar_t *)w << 8;
 486 #endif
 487                                 byteleft = B_TRUE;
 488                         }
 489                 } else {
 490                         ushort_t swsum;
 491 #ifdef _LITTLE_ENDIAN
 492                         sum += *(uchar_t *)w;
 493 #else
 494                         sum += *(uchar_t *)w << 8;
 495 #endif
 496                         mlen--;
 497                         w = (ushort_t *)(1 + (uintptr_t)w);
 498 
 499                         /* Do a separate checksum and copy operation */
 500                         swsum = ip_ocsum(w, mlen >> 1, 0);
 501                         sum += ((swsum << 8) & 0xffff) | (swsum >> 8);
 502                         w += mlen >> 1;
 503                         /*
 504                          * If we had an even number of bytes,
 505                          * then the last byte goes in the low
 506                          * part of the sum.  Otherwise we had an
 507                          * odd number of bytes and we take the first
 508                          * byte to the low part of the sum the
 509                          * next time around the loop.
 510                          */
 511                         if (is_odd(mlen)) {
 512 #ifdef _LITTLE_ENDIAN
 513                                 sum += *(uchar_t *)w << 8;
 514 #else
 515                                 sum += *(uchar_t *)w;
 516 #endif
 517                         } else {
 518                                 byteleft = B_TRUE;
 519                         }
 520                 }
 521         }
 522 
 523         /*
 524          * Add together high and low parts of sum and carry to get cksum.
 525          * Have to be careful to not drop the last carry here.
 526          */
 527         sum = (sum & 0xffff) + (sum >> 16);
 528         sum = (sum & 0xffff) + (sum >> 16);
 529 
 530         return (sum);
 531 }
 532 
 533 /* Return the IP checksum for the IP header at "iph". */
 534 uint16_t
 535 ip_csum_hdr(ipha_t *ipha)
 536 {
 537         uint16_t        *uph;
 538         uint32_t        sum;
 539         int             opt_len;
 540 
 541         opt_len = (ipha->ipha_version_and_hdr_length & 0xF) -
 542             IP_SIMPLE_HDR_LENGTH_IN_WORDS;
 543         uph = (uint16_t *)ipha;
 544         sum = uph[0] + uph[1] + uph[2] + uph[3] + uph[4] +
 545             uph[5] + uph[6] + uph[7] + uph[8] + uph[9];
 546         if (opt_len > 0) {
 547                 do {
 548                         sum += uph[10];
 549                         sum += uph[11];
 550                         uph += 2;
 551                 } while (--opt_len);
 552         }
 553         sum = (sum & 0xFFFF) + (sum >> 16);
 554         sum = ~(sum + (sum >> 16)) & 0xFFFF;
 555         if (sum == 0xffff)
 556                 sum = 0;
 557         return ((uint16_t)sum);
 558 }
--- EOF ---