icuSources/common/uidna.cpp

   1 /*
   2  *******************************************************************************
   3  *
   4  *   Copyright (C) 2003-2014, International Business Machines
   5  *   Corporation and others.  All Rights Reserved.
   6  *
   7  *******************************************************************************
   8  *   file name:  uidna.cpp
   9  *   encoding:   US-ASCII
  10  *   tab size:   8 (not used)
  11  *   indentation:4
  12  *
  13  *   created on: 2003feb1
  14  *   created by: Ram Viswanadha
  15  */
  16
  17 #include "unicode/utypes.h"
  18
  19 #if !UCONFIG_NO_IDNA
  20
  21 #include "unicode/uidna.h"
  22 #include "unicode/ustring.h"
  23 #include "unicode/usprep.h"
  24 #include "punycode.h"
  25 #include "ustr_imp.h"
  26 #include "cmemory.h"
  27 #include "uassert.h"
  28 #include "sprpimpl.h"
  29
  30 /* it is official IDNA ACE Prefix is "xn--" */
  31 static const UChar ACE_PREFIX[] ={ 0x0078,0x006E,0x002d,0x002d } ;
  32 #define ACE_PREFIX_LENGTH 4
  33
  34 #define MAX_LABEL_LENGTH 63
  35 /* The Max length of the labels should not be more than MAX_LABEL_LENGTH */
  36 #define MAX_LABEL_BUFFER_SIZE 100
  37
  38 #define MAX_DOMAIN_NAME_LENGTH 255
  39 /* The Max length of the domain names should not be more than MAX_DOMAIN_NAME_LENGTH */
  40 #define MAX_IDN_BUFFER_SIZE   MAX_DOMAIN_NAME_LENGTH+1
  41
  42 #define LOWER_CASE_DELTA 0x0020
  43 #define HYPHEN           0x002D
  44 #define FULL_STOP        0x002E
  45 #define CAPITAL_A        0x0041
  46 #define CAPITAL_Z        0x005A
  47
  48 inline static UChar
  49 toASCIILower(UChar ch){
  50     if(CAPITAL_A <= ch && ch <= CAPITAL_Z){
  51         return ch + LOWER_CASE_DELTA;
  52     }
  53     return ch;
  54 }
  55
  56 inline static UBool
  57 startsWithPrefix(const UChar* src , int32_t srcLength){
  58     UBool startsWithPrefix = TRUE;
  59
  60     if(srcLength < ACE_PREFIX_LENGTH){
  61         return FALSE;
  62     }
  63
  64     for(int8_t i=0; i< ACE_PREFIX_LENGTH; i++){
  65         if(toASCIILower(src[i]) != ACE_PREFIX[i]){
  66             startsWithPrefix = FALSE;
  67         }
  68     }
  69     return startsWithPrefix;
  70 }
  71
  72
  73 inline static int32_t
  74 compareCaseInsensitiveASCII(const UChar* s1, int32_t s1Len,
  75                             const UChar* s2, int32_t s2Len){
  76
  77     int32_t minLength;
  78     int32_t lengthResult;
  79
  80     // are we comparing different lengths?
  81     if(s1Len != s2Len) {
  82         if(s1Len < s2Len) {
  83             minLength = s1Len;
  84             lengthResult = -1;
  85         } else {
  86             minLength = s2Len;
  87             lengthResult = 1;
  88         }
  89     } else {
  90         // ok the lengths are equal
  91         minLength = s1Len;
  92         lengthResult = 0;
  93     }
  94
  95     UChar c1,c2;
  96     int32_t rc;
  97
  98     for(int32_t i =0;/* no condition */;i++) {
  99
 100         /* If we reach the ends of both strings then they match */
 101         if(i == minLength) {
 102             return lengthResult;
 103         }
 104
 105         c1 = s1[i];
 106         c2 = s2[i];
 107
 108         /* Case-insensitive comparison */
 109         if(c1!=c2) {
 110             rc=(int32_t)toASCIILower(c1)-(int32_t)toASCIILower(c2);
 111             if(rc!=0) {
 112                 lengthResult=rc;
 113                 break;
 114             }
 115         }
 116     }
 117     return lengthResult;
 118 }
 119
 120
 121 /**
 122  * Ascertain if the given code point is a label separator as
 123  * defined by the IDNA RFC
 124  *
 125  * @param ch The code point to be ascertained
 126  * @return true if the char is a label separator
 127  * @stable ICU 2.8
 128  */
 129 static inline UBool isLabelSeparator(UChar ch){
 130     switch(ch){
 131         case 0x002e:
 132         case 0x3002:
 133         case 0xFF0E:
 134         case 0xFF61:
 135             return TRUE;
 136         default:
 137             return FALSE;
 138     }
 139 }
 140
 141 // returns the length of the label excluding the separator
 142 // if *limit == separator then the length returned does not include
 143 // the separtor.
 144 static inline int32_t
 145 getNextSeparator(UChar *src, int32_t srcLength,
 146                  UChar **limit, UBool *done){
 147     if(srcLength == -1){
 148         int32_t i;
 149         for(i=0 ; ;i++){
 150             if(src[i] == 0){
 151                 *limit = src + i; // point to null
 152                 *done = TRUE;
 153                 return i;
 154             }
 155             if(isLabelSeparator(src[i])){
 156                 *limit = src + (i+1); // go past the delimiter
 157                 return i;
 158
 159             }
 160         }
 161     }else{
 162         int32_t i;
 163         for(i=0;i<srcLength;i++){
 164             if(isLabelSeparator(src[i])){
 165                 *limit = src + (i+1); // go past the delimiter
 166                 return i;
 167             }
 168         }
 169         // we have not found the delimiter
 170         // if(i==srcLength)
 171         *limit = src+srcLength;
 172         *done = TRUE;
 173
 174         return i;
 175     }
 176 }
 177 static inline UBool isLDHChar(UChar ch){
 178     // high runner case
 179     if(ch>0x007A){
 180         return FALSE;
 181     }
 182     //[\\u002D \\u0030-\\u0039 \\u0041-\\u005A \\u0061-\\u007A]
 183     if( (ch==0x002D) ||
 184         (0x0030 <= ch && ch <= 0x0039) ||
 185         (0x0041 <= ch && ch <= 0x005A) ||
 186         (0x0061 <= ch && ch <= 0x007A)
 187       ){
 188         return TRUE;
 189     }
 190     return FALSE;
 191 }
 192
 193 static int32_t
 194 _internal_toASCII(const UChar* src, int32_t srcLength,
 195                   UChar* dest, int32_t destCapacity,
 196                   int32_t options,
 197                   UStringPrepProfile* nameprep,
 198                   UParseError* parseError,
 199                   UErrorCode* status)
 200 {
 201
 202     // TODO Revisit buffer handling. The label should not be over 63 ASCII characters. ICU4J may need to be updated too.
 203     UChar b1Stack[MAX_LABEL_BUFFER_SIZE], b2Stack[MAX_LABEL_BUFFER_SIZE];
 204     //initialize pointers to stack buffers
 205     UChar  *b1 = b1Stack, *b2 = b2Stack;
 206     int32_t b1Len=0, b2Len,
 207             b1Capacity = MAX_LABEL_BUFFER_SIZE,
 208             b2Capacity = MAX_LABEL_BUFFER_SIZE ,
 209             reqLength=0;
 210
 211     int32_t namePrepOptions = ((options & UIDNA_ALLOW_UNASSIGNED) != 0) ? USPREP_ALLOW_UNASSIGNED: 0;
 212     UBool* caseFlags = NULL;
 213
 214     // the source contains all ascii codepoints
 215     UBool srcIsASCII  = TRUE;
 216     // assume the source contains all LDH codepoints
 217     UBool srcIsLDH = TRUE;
 218
 219     int32_t j=0;
 220
 221     //get the options
 222     UBool useSTD3ASCIIRules = (UBool)((options & UIDNA_USE_STD3_RULES) != 0);
 223
 224     int32_t failPos = -1;
 225
 226     if(srcLength == -1){
 227         srcLength = u_strlen(src);
 228     }
 229
 230     if(srcLength > b1Capacity){
 231         b1 = (UChar*) uprv_malloc(srcLength * U_SIZEOF_UCHAR);
 232         if(b1==NULL){
 233             *status = U_MEMORY_ALLOCATION_ERROR;
 234             goto CLEANUP;
 235         }
 236         b1Capacity = srcLength;
 237     }
 238
 239     // step 1
 240     for( j=0;j<srcLength;j++){
 241         if(src[j] > 0x7F){
 242             srcIsASCII = FALSE;
 243         }
 244         b1[b1Len++] = src[j];
 245     }
 246
 247     // step 2 is performed only if the source contains non ASCII
 248     if(srcIsASCII == FALSE){
 249
 250         // step 2
 251         b1Len = usprep_prepare(nameprep, src, srcLength, b1, b1Capacity, namePrepOptions, parseError, status);
 252
 253         if(*status == U_BUFFER_OVERFLOW_ERROR){
 254             // redo processing of string
 255             // we do not have enough room so grow the buffer
 256             if(b1 != b1Stack){
 257                 uprv_free(b1);
 258             }
 259             b1 = (UChar*) uprv_malloc(b1Len * U_SIZEOF_UCHAR);
 260             if(b1==NULL){
 261                 *status = U_MEMORY_ALLOCATION_ERROR;
 262                 goto CLEANUP;
 263             }
 264
 265             *status = U_ZERO_ERROR; // reset error
 266
 267             b1Len = usprep_prepare(nameprep, src, srcLength, b1, b1Len, namePrepOptions, parseError, status);
 268         }
 269     }
 270     // error bail out
 271     if(U_FAILURE(*status)){
 272         goto CLEANUP;
 273     }
 274     if(b1Len == 0){
 275         *status = U_IDNA_ZERO_LENGTH_LABEL_ERROR;
 276         goto CLEANUP;
 277     }
 278
 279     // for step 3 & 4
 280     srcIsASCII = TRUE;
 281     for( j=0;j<b1Len;j++){
 282         // check if output of usprep_prepare is all ASCII
 283         if(b1[j] > 0x7F){
 284             srcIsASCII = FALSE;
 285         }else if(isLDHChar(b1[j])==FALSE){  // if the char is in ASCII range verify that it is an LDH character
 286             srcIsLDH = FALSE;
 287             failPos = j;
 288         }
 289     }
 290     if(useSTD3ASCIIRules == TRUE){
 291         // verify 3a and 3b
 292         // 3(a) Verify the absence of non-LDH ASCII code points; that is, the
 293         //  absence of 0..2C, 2E..2F, 3A..40, 5B..60, and 7B..7F.
 294         // 3(b) Verify the absence of leading and trailing hyphen-minus; that
 295         //  is, the absence of U+002D at the beginning and end of the
 296         //  sequence.
 297         if( srcIsLDH == FALSE /* source at this point should not contain anyLDH characters */
 298             || b1[0] ==  HYPHEN || b1[b1Len-1] == HYPHEN){
 299             *status = U_IDNA_STD3_ASCII_RULES_ERROR;
 300
 301             /* populate the parseError struct */
 302             if(srcIsLDH==FALSE){
 303                 // failPos is always set the index of failure
 304                 uprv_syntaxError(b1,failPos, b1Len,parseError);
 305             }else if(b1[0] == HYPHEN){
 306                 // fail position is 0
 307                 uprv_syntaxError(b1,0,b1Len,parseError);
 308             }else{
 309                 // the last index in the source is always length-1
 310                 uprv_syntaxError(b1, (b1Len>0) ? b1Len-1 : b1Len, b1Len,parseError);
 311             }
 312
 313             goto CLEANUP;
 314         }
 315     }
 316     // Step 4: if the source is ASCII then proceed to step 8
 317     if(srcIsASCII){
 318         if(b1Len <= destCapacity){
 319             uprv_memmove(dest, b1, b1Len * U_SIZEOF_UCHAR);
 320             reqLength = b1Len;
 321         }else{
 322             reqLength = b1Len;
 323             goto CLEANUP;
 324         }
 325     }else{
 326         // step 5 : verify the sequence does not begin with ACE prefix
 327         if(!startsWithPrefix(b1,b1Len)){
 328
 329             //step 6: encode the sequence with punycode
 330
 331             // do not preserve the case flags for now!
 332             // TODO: Preserve the case while implementing the RFE
 333             // caseFlags = (UBool*) uprv_malloc(b1Len * sizeof(UBool));
 334             // uprv_memset(caseFlags,TRUE,b1Len);
 335
 336             b2Len = u_strToPunycode(b1,b1Len,b2,b2Capacity,caseFlags, status);
 337
 338             if(*status == U_BUFFER_OVERFLOW_ERROR){
 339                 // redo processing of string
 340                 /* we do not have enough room so grow the buffer*/
 341                 b2 = (UChar*) uprv_malloc(b2Len * U_SIZEOF_UCHAR);
 342                 if(b2 == NULL){
 343                     *status = U_MEMORY_ALLOCATION_ERROR;
 344                     goto CLEANUP;
 345                 }
 346
 347                 *status = U_ZERO_ERROR; // reset error
 348
 349                 b2Len = u_strToPunycode(b1,b1Len,b2,b2Len,caseFlags, status);
 350             }
 351             //error bail out
 352             if(U_FAILURE(*status)){
 353                 goto CLEANUP;
 354             }
 355             // TODO : Reconsider while implementing the case preserve RFE
 356             // convert all codepoints to lower case ASCII
 357             // toASCIILower(b2,b2Len);
 358             reqLength = b2Len+ACE_PREFIX_LENGTH;
 359
 360             if(reqLength > destCapacity){
 361                 *status = U_BUFFER_OVERFLOW_ERROR;
 362                 goto CLEANUP;
 363             }
 364             //Step 7: prepend the ACE prefix
 365             uprv_memcpy(dest,ACE_PREFIX,ACE_PREFIX_LENGTH * U_SIZEOF_UCHAR);
 366             //Step 6: copy the contents in b2 into dest
 367             uprv_memcpy(dest+ACE_PREFIX_LENGTH, b2, b2Len * U_SIZEOF_UCHAR);
 368
 369         }else{
 370             *status = U_IDNA_ACE_PREFIX_ERROR;
 371             //position of failure is 0
 372             uprv_syntaxError(b1,0,b1Len,parseError);
 373             goto CLEANUP;
 374         }
 375     }
 376     // step 8: verify the length of label
 377     if(reqLength > MAX_LABEL_LENGTH){
 378         *status = U_IDNA_LABEL_TOO_LONG_ERROR;
 379     }
 380
 381 CLEANUP:
 382     if(b1 != b1Stack){
 383         uprv_free(b1);
 384     }
 385     if(b2 != b2Stack){
 386         uprv_free(b2);
 387     }
 388     uprv_free(caseFlags);
 389
 390     return u_terminateUChars(dest, destCapacity, reqLength, status);
 391 }
 392
 393 static int32_t
 394 _internal_toUnicode(const UChar* src, int32_t srcLength,
 395                     UChar* dest, int32_t destCapacity,
 396                     int32_t options,
 397                     UStringPrepProfile* nameprep,
 398                     UParseError* parseError,
 399                     UErrorCode* status)
 400 {
 401
 402     //get the options
 403     //UBool useSTD3ASCIIRules = (UBool)((options & UIDNA_USE_STD3_RULES) != 0);
 404     int32_t namePrepOptions = ((options & UIDNA_ALLOW_UNASSIGNED) != 0) ? USPREP_ALLOW_UNASSIGNED: 0;
 405
 406     // TODO Revisit buffer handling. The label should not be over 63 ASCII characters. ICU4J may need to be updated too.
 407     UChar b1Stack[MAX_LABEL_BUFFER_SIZE], b2Stack[MAX_LABEL_BUFFER_SIZE], b3Stack[MAX_LABEL_BUFFER_SIZE];
 408
 409     //initialize pointers to stack buffers
 410     UChar  *b1 = b1Stack, *b2 = b2Stack, *b1Prime=NULL, *b3=b3Stack;
 411     int32_t b1Len = 0, b2Len, b1PrimeLen, b3Len,
 412             b1Capacity = MAX_LABEL_BUFFER_SIZE,
 413             b2Capacity = MAX_LABEL_BUFFER_SIZE,
 414             b3Capacity = MAX_LABEL_BUFFER_SIZE,
 415             reqLength=0;
 416
 417     UBool* caseFlags = NULL;
 418
 419     UBool srcIsASCII = TRUE;
 420     /*UBool srcIsLDH = TRUE;
 421     int32_t failPos =0;*/
 422
 423     // step 1: find out if all the codepoints in src are ASCII
 424     if(srcLength==-1){
 425         srcLength = 0;
 426         for(;src[srcLength]!=0;){
 427             if(src[srcLength]> 0x7f){
 428                 srcIsASCII = FALSE;
 429             }/*else if(isLDHChar(src[srcLength])==FALSE){
 430                 // here we do not assemble surrogates
 431                 // since we know that LDH code points
 432                 // are in the ASCII range only
 433                 srcIsLDH = FALSE;
 434                 failPos = srcLength;
 435             }*/
 436             srcLength++;
 437         }
 438     }else if(srcLength > 0){
 439         for(int32_t j=0; j<srcLength; j++){
 440             if(src[j]> 0x7f){
 441                 srcIsASCII = FALSE;
 442             }/*else if(isLDHChar(src[j])==FALSE){
 443                 // here we do not assemble surrogates
 444                 // since we know that LDH code points
 445                 // are in the ASCII range only
 446                 srcIsLDH = FALSE;
 447                 failPos = j;
 448             }*/
 449         }
 450     }else{
 451         return 0;
 452     }
 453
 454     if(srcIsASCII == FALSE){
 455         // step 2: process the string
 456         b1Len = usprep_prepare(nameprep, src, srcLength, b1, b1Capacity, namePrepOptions, parseError, status);
 457         if(*status == U_BUFFER_OVERFLOW_ERROR){
 458             // redo processing of string
 459             /* we do not have enough room so grow the buffer*/
 460             b1 = (UChar*) uprv_malloc(b1Len * U_SIZEOF_UCHAR);
 461             if(b1==NULL){
 462                 *status = U_MEMORY_ALLOCATION_ERROR;
 463                 goto CLEANUP;
 464             }
 465
 466             *status = U_ZERO_ERROR; // reset error
 467
 468             b1Len = usprep_prepare(nameprep, src, srcLength, b1, b1Len, namePrepOptions, parseError, status);
 469         }
 470         //bail out on error
 471         if(U_FAILURE(*status)){
 472             goto CLEANUP;
 473         }
 474     }else{
 475
 476         //just point src to b1
 477         b1 = (UChar*) src;
 478         b1Len = srcLength;
 479     }
 480
 481     // The RFC states that
 482     // <quote>
 483     // ToUnicode never fails. If any step fails, then the original input
 484     // is returned immediately in that step.
 485     // </quote>
 486
 487     //step 3: verify ACE Prefix
 488     if(startsWithPrefix(b1,b1Len)){
 489
 490         //step 4: Remove the ACE Prefix
 491         b1Prime = b1 + ACE_PREFIX_LENGTH;
 492         b1PrimeLen  = b1Len - ACE_PREFIX_LENGTH;
 493
 494         //step 5: Decode using punycode
 495         b2Len = u_strFromPunycode(b1Prime, b1PrimeLen, b2, b2Capacity, caseFlags,status);
 496
 497         if(*status == U_BUFFER_OVERFLOW_ERROR){
 498             // redo processing of string
 499             /* we do not have enough room so grow the buffer*/
 500             b2 = (UChar*) uprv_malloc(b2Len * U_SIZEOF_UCHAR);
 501             if(b2==NULL){
 502                 *status = U_MEMORY_ALLOCATION_ERROR;
 503                 goto CLEANUP;
 504             }
 505
 506             *status = U_ZERO_ERROR; // reset error
 507
 508             b2Len =  u_strFromPunycode(b1Prime, b1PrimeLen, b2, b2Len, caseFlags, status);
 509         }
 510
 511
 512         //step 6:Apply toASCII
 513         b3Len = uidna_toASCII(b2, b2Len, b3, b3Capacity, options, parseError, status);
 514
 515         if(*status == U_BUFFER_OVERFLOW_ERROR){
 516             // redo processing of string
 517             /* we do not have enough room so grow the buffer*/
 518             b3 = (UChar*) uprv_malloc(b3Len * U_SIZEOF_UCHAR);
 519             if(b3==NULL){
 520                 *status = U_MEMORY_ALLOCATION_ERROR;
 521                 goto CLEANUP;
 522             }
 523
 524             *status = U_ZERO_ERROR; // reset error
 525
 526             b3Len =  uidna_toASCII(b2,b2Len,b3,b3Len,options,parseError, status);
 527
 528         }
 529         //bail out on error
 530         if(U_FAILURE(*status)){
 531             goto CLEANUP;
 532         }
 533
 534         //step 7: verify
 535         if(compareCaseInsensitiveASCII(b1, b1Len, b3, b3Len) !=0){
 536             // Cause the original to be returned.
 537             *status = U_IDNA_VERIFICATION_ERROR;
 538             goto CLEANUP;
 539         }
 540
 541         //step 8: return output of step 5
 542         reqLength = b2Len;
 543         if(b2Len <= destCapacity) {
 544             uprv_memmove(dest, b2, b2Len * U_SIZEOF_UCHAR);
 545         }
 546     }
 547     else{
 548         // See the start of this if statement for why this is commented out.
 549         // verify that STD3 ASCII rules are satisfied
 550         /*if(useSTD3ASCIIRules == TRUE){
 551             if( srcIsLDH == FALSE // source contains some non-LDH characters
 552                 || src[0] ==  HYPHEN || src[srcLength-1] == HYPHEN){
 553                 *status = U_IDNA_STD3_ASCII_RULES_ERROR;
 554
 555                 // populate the parseError struct
 556                 if(srcIsLDH==FALSE){
 557                     // failPos is always set the index of failure
 558                     uprv_syntaxError(src,failPos, srcLength,parseError);
 559                 }else if(src[0] == HYPHEN){
 560                     // fail position is 0
 561                     uprv_syntaxError(src,0,srcLength,parseError);
 562                 }else{
 563                     // the last index in the source is always length-1
 564                     uprv_syntaxError(src, (srcLength>0) ? srcLength-1 : srcLength, srcLength,parseError);
 565                 }
 566
 567                 goto CLEANUP;
 568             }
 569         }*/
 570         // just return the source
 571         //copy the source to destination
 572         if(srcLength <= destCapacity){
 573             uprv_memmove(dest,src,srcLength * U_SIZEOF_UCHAR);
 574         }
 575         reqLength = srcLength;
 576     }
 577
 578
 579 CLEANUP:
 580
 581     if(b1 != b1Stack && b1!=src){
 582         uprv_free(b1);
 583     }
 584     if(b2 != b2Stack){
 585         uprv_free(b2);
 586     }
 587     uprv_free(caseFlags);
 588
 589     // The RFC states that
 590     // <quote>
 591     // ToUnicode never fails. If any step fails, then the original input
 592     // is returned immediately in that step.
 593     // </quote>
 594     // So if any step fails lets copy source to destination
 595     if(U_FAILURE(*status)){
 596         //copy the source to destination
 597         if(dest && srcLength <= destCapacity){
 598             // srcLength should have already been set earlier.
 599             U_ASSERT(srcLength >= 0);
 600             uprv_memmove(dest,src,srcLength * U_SIZEOF_UCHAR);
 601         }
 602         reqLength = srcLength;
 603         *status = U_ZERO_ERROR;
 604     }
 605
 606     return u_terminateUChars(dest, destCapacity, reqLength, status);
 607 }
 608
 609 U_CAPI int32_t U_EXPORT2
 610 uidna_toASCII(const UChar* src, int32_t srcLength,
 611               UChar* dest, int32_t destCapacity,
 612               int32_t options,
 613               UParseError* parseError,
 614               UErrorCode* status){
 615
 616     if(status == NULL || U_FAILURE(*status)){
 617         return 0;
 618     }
 619     if((src==NULL) || (srcLength < -1) || (destCapacity<0) || (!dest && destCapacity > 0)){
 620         *status = U_ILLEGAL_ARGUMENT_ERROR;
 621         return 0;
 622     }
 623
 624     UStringPrepProfile* nameprep = usprep_openByType(USPREP_RFC3491_NAMEPREP, status);
 625
 626     if(U_FAILURE(*status)){
 627         return -1;
 628     }
 629
 630     int32_t retLen = _internal_toASCII(src, srcLength, dest, destCapacity, options, nameprep, parseError, status);
 631
 632     /* close the profile*/
 633     usprep_close(nameprep);
 634
 635     return retLen;
 636 }
 637
 638 U_CAPI int32_t U_EXPORT2
 639 uidna_toUnicode(const UChar* src, int32_t srcLength,
 640                 UChar* dest, int32_t destCapacity,
 641                 int32_t options,
 642                 UParseError* parseError,
 643                 UErrorCode* status){
 644
 645     if(status == NULL || U_FAILURE(*status)){
 646         return 0;
 647     }
 648     if( (src==NULL) || (srcLength < -1) || (destCapacity<0) || (!dest && destCapacity > 0)){
 649         *status = U_ILLEGAL_ARGUMENT_ERROR;
 650         return 0;
 651     }
 652
 653     UStringPrepProfile* nameprep = usprep_openByType(USPREP_RFC3491_NAMEPREP, status);
 654
 655     if(U_FAILURE(*status)){
 656         return -1;
 657     }
 658
 659     int32_t retLen = _internal_toUnicode(src, srcLength, dest, destCapacity, options, nameprep, parseError, status);
 660
 661     usprep_close(nameprep);
 662
 663     return retLen;
 664 }
 665
 666
 667 U_CAPI int32_t U_EXPORT2
 668 uidna_IDNToASCII(  const UChar *src, int32_t srcLength,
 669                    UChar* dest, int32_t destCapacity,
 670                    int32_t options,
 671                    UParseError *parseError,
 672                    UErrorCode *status){
 673
 674     if(status == NULL || U_FAILURE(*status)){
 675         return 0;
 676     }
 677     if((src==NULL) || (srcLength < -1) || (destCapacity<0) || (!dest && destCapacity > 0)){
 678         *status = U_ILLEGAL_ARGUMENT_ERROR;
 679         return 0;
 680     }
 681
 682     int32_t reqLength = 0;
 683
 684     UStringPrepProfile* nameprep = usprep_openByType(USPREP_RFC3491_NAMEPREP, status);
 685
 686     if(U_FAILURE(*status)){
 687         return 0;
 688     }
 689
 690     //initialize pointers
 691     UChar *delimiter = (UChar*)src;
 692     UChar *labelStart = (UChar*)src;
 693     UChar *currentDest = (UChar*) dest;
 694     int32_t remainingLen = srcLength;
 695     int32_t remainingDestCapacity = destCapacity;
 696     int32_t labelLen = 0, labelReqLength = 0;
 697     UBool done = FALSE;
 698
 699
 700     for(;;){
 701
 702         labelLen = getNextSeparator(labelStart,remainingLen, &delimiter,&done);
 703         labelReqLength = 0;
 704         if(!(labelLen==0 && done)){// make sure this is not a root label separator.
 705
 706             labelReqLength = _internal_toASCII( labelStart, labelLen,
 707                                                 currentDest, remainingDestCapacity,
 708                                                 options, nameprep,
 709                                                 parseError, status);
 710
 711             if(*status == U_BUFFER_OVERFLOW_ERROR){
 712
 713                 *status = U_ZERO_ERROR; // reset error
 714                 remainingDestCapacity = 0;
 715             }
 716         }
 717
 718
 719         if(U_FAILURE(*status)){
 720             break;
 721         }
 722
 723         reqLength +=labelReqLength;
 724         // adjust the destination pointer
 725         if(labelReqLength < remainingDestCapacity){
 726             currentDest = currentDest + labelReqLength;
 727             remainingDestCapacity -= labelReqLength;
 728         }else{
 729             // should never occur
 730             remainingDestCapacity = 0;
 731         }
 732
 733         if(done == TRUE){
 734             break;
 735         }
 736
 737         // add the label separator
 738         if(remainingDestCapacity > 0){
 739             *currentDest++ = FULL_STOP;
 740             remainingDestCapacity--;
 741         }
 742         reqLength++;
 743
 744         labelStart = delimiter;
 745         if(remainingLen >0 ){
 746             remainingLen = (int32_t)(srcLength - (delimiter - src));
 747         }
 748
 749     }
 750
 751     if(reqLength > MAX_DOMAIN_NAME_LENGTH){
 752         *status = U_IDNA_DOMAIN_NAME_TOO_LONG_ERROR;
 753     }
 754
 755     usprep_close(nameprep);
 756
 757     return u_terminateUChars(dest, destCapacity, reqLength, status);
 758 }
 759
 760 U_CAPI int32_t U_EXPORT2
 761 uidna_IDNToUnicode(  const UChar* src, int32_t srcLength,
 762                      UChar* dest, int32_t destCapacity,
 763                      int32_t options,
 764                      UParseError* parseError,
 765                      UErrorCode* status){
 766
 767     if(status == NULL || U_FAILURE(*status)){
 768         return 0;
 769     }
 770     if((src==NULL) || (srcLength < -1) || (destCapacity<0) || (!dest && destCapacity > 0)){
 771         *status = U_ILLEGAL_ARGUMENT_ERROR;
 772         return 0;
 773     }
 774
 775     int32_t reqLength = 0;
 776
 777     UStringPrepProfile* nameprep = usprep_openByType(USPREP_RFC3491_NAMEPREP, status);
 778
 779     if(U_FAILURE(*status)){
 780         return 0;
 781     }
 782
 783     //initialize pointers
 784     UChar *delimiter = (UChar*)src;
 785     UChar *labelStart = (UChar*)src;
 786     UChar *currentDest = (UChar*) dest;
 787     int32_t remainingLen = srcLength;
 788     int32_t remainingDestCapacity = destCapacity;
 789     int32_t labelLen = 0, labelReqLength = 0;
 790     UBool done = FALSE;
 791
 792     for(;;){
 793
 794         labelLen = getNextSeparator(labelStart,remainingLen, &delimiter,&done);
 795
 796         // The RFC states that
 797         // <quote>
 798         // ToUnicode never fails. If any step fails, then the original input
 799         // is returned immediately in that step.
 800         // </quote>
 801         // _internal_toUnicode will copy the label.
 802         /*if(labelLen==0 && done==FALSE){
 803             *status = U_IDNA_ZERO_LENGTH_LABEL_ERROR;
 804             break;
 805         }*/
 806
 807         labelReqLength = _internal_toUnicode(labelStart, labelLen,
 808                                              currentDest, remainingDestCapacity,
 809                                              options, nameprep,
 810                                              parseError, status);
 811
 812         if(*status == U_BUFFER_OVERFLOW_ERROR){
 813             *status = U_ZERO_ERROR; // reset error
 814             remainingDestCapacity = 0;
 815         }
 816
 817         if(U_FAILURE(*status)){
 818             break;
 819         }
 820
 821         reqLength +=labelReqLength;
 822         // adjust the destination pointer
 823         if(labelReqLength < remainingDestCapacity){
 824             currentDest = currentDest + labelReqLength;
 825             remainingDestCapacity -= labelReqLength;
 826         }else{
 827             // should never occur
 828             remainingDestCapacity = 0;
 829         }
 830
 831         if(done == TRUE){
 832             break;
 833         }
 834
 835         // add the label separator
 836         // Unlike the ToASCII operation we don't normalize the label separators
 837         if(remainingDestCapacity > 0){
 838             *currentDest++ = *(labelStart + labelLen);
 839             remainingDestCapacity--;
 840         }
 841         reqLength++;
 842
 843         labelStart = delimiter;
 844         if(remainingLen >0 ){
 845             remainingLen = (int32_t)(srcLength - (delimiter - src));
 846         }
 847
 848     }
 849
 850     if(reqLength > MAX_DOMAIN_NAME_LENGTH){
 851         *status = U_IDNA_DOMAIN_NAME_TOO_LONG_ERROR;
 852     }
 853
 854     usprep_close(nameprep);
 855
 856     return u_terminateUChars(dest, destCapacity, reqLength, status);
 857 }
 858
 859 U_CAPI int32_t U_EXPORT2
 860 uidna_compare(  const UChar *s1, int32_t length1,
 861                 const UChar *s2, int32_t length2,
 862                 int32_t options,
 863                 UErrorCode* status){
 864
 865     if(status == NULL || U_FAILURE(*status)){
 866         return -1;
 867     }
 868
 869     UChar b1Stack[MAX_IDN_BUFFER_SIZE], b2Stack[MAX_IDN_BUFFER_SIZE];
 870     UChar *b1 = b1Stack, *b2 = b2Stack;
 871     int32_t b1Len, b2Len, b1Capacity = MAX_IDN_BUFFER_SIZE, b2Capacity = MAX_IDN_BUFFER_SIZE;
 872     int32_t result=-1;
 873
 874     UParseError parseError;
 875
 876     b1Len = uidna_IDNToASCII(s1, length1, b1, b1Capacity, options, &parseError, status);
 877     if(*status == U_BUFFER_OVERFLOW_ERROR){
 878         // redo processing of string
 879         b1 = (UChar*) uprv_malloc(b1Len * U_SIZEOF_UCHAR);
 880         if(b1==NULL){
 881             *status = U_MEMORY_ALLOCATION_ERROR;
 882             goto CLEANUP;
 883         }
 884
 885         *status = U_ZERO_ERROR; // reset error
 886
 887         b1Len = uidna_IDNToASCII(s1,length1,b1,b1Len, options, &parseError, status);
 888
 889     }
 890
 891     b2Len = uidna_IDNToASCII(s2,length2, b2,b2Capacity, options, &parseError, status);
 892     if(*status == U_BUFFER_OVERFLOW_ERROR){
 893         // redo processing of string
 894         b2 = (UChar*) uprv_malloc(b2Len * U_SIZEOF_UCHAR);
 895         if(b2==NULL){
 896             *status = U_MEMORY_ALLOCATION_ERROR;
 897             goto CLEANUP;
 898         }
 899
 900         *status = U_ZERO_ERROR; // reset error
 901
 902         b2Len = uidna_IDNToASCII(s2, length2, b2, b2Len, options, &parseError, status);
 903
 904     }
 905     // when toASCII is applied all label separators are replaced with FULL_STOP
 906     result = compareCaseInsensitiveASCII(b1,b1Len,b2,b2Len);
 907
 908 CLEANUP:
 909     if(b1 != b1Stack){
 910         uprv_free(b1);
 911     }
 912
 913     if(b2 != b2Stack){
 914         uprv_free(b2);
 915     }
 916
 917     return result;
 918 }
 919
 920 #endif /* #if !UCONFIG_NO_IDNA */