libsecurity_smime/lib/secitem.c

   1 /*
   2  * The contents of this file are subject to the Mozilla Public
   3  * License Version 1.1 (the "License"); you may not use this file
   4  * except in compliance with the License. You may obtain a copy of
   5  * the License at http://www.mozilla.org/MPL/
   6  *
   7  * Software distributed under the License is distributed on an "AS
   8  * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
   9  * implied. See the License for the specific language governing
  10  * rights and limitations under the License.
  11  *
  12  * The Original Code is the Netscape security libraries.
  13  *
  14  * The Initial Developer of the Original Code is Netscape
  15  * Communications Corporation.  Portions created by Netscape are
  16  * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
  17  * Rights Reserved.
  18  *
  19  * Contributor(s):
  20  *
  21  * Alternatively, the contents of this file may be used under the
  22  * terms of the GNU General Public License Version 2 or later (the
  23  * "GPL"), in which case the provisions of the GPL are applicable
  24  * instead of those above.  If you wish to allow use of your
  25  * version of this file only under the terms of the GPL and not to
  26  * allow others to use your version of this file under the MPL,
  27  * indicate your decision by deleting the provisions above and
  28  * replace them with the notice and other provisions required by
  29  * the GPL.  If you do not delete the provisions above, a recipient
  30  * may use your version of this file under either the MPL or the
  31  * GPL.
  32  */
  33
  34 /*
  35  * Support routines for SECItem data structure.
  36  */
  37
  38 #include "secitem.h"
  39 #include <security_asn1/seccomon.h>
  40 #include <security_asn1/secerr.h>
  41
  42 SECItem *
  43 SECITEM_AllocItem(PRArenaPool *arena, SECItem *item, unsigned int len)
  44 {
  45     SECItem *result = NULL;
  46     void *mark = NULL;
  47
  48     if (arena != NULL) {
  49         mark = PORT_ArenaMark(arena);
  50     }
  51
  52     if (item == NULL) {
  53         if (arena != NULL) {
  54             result = PORT_ArenaZAlloc(arena, sizeof(SECItem));
  55         } else {
  56             result = PORT_ZAlloc(sizeof(SECItem));
  57         }
  58         if (result == NULL) {
  59             goto loser;
  60         }
  61     } else {
  62         PORT_Assert(item->Data == NULL);
  63         result = item;
  64     }
  65
  66     result->Length = len;
  67     if (len) {
  68         if (arena != NULL) {
  69             result->Data = PORT_ArenaAlloc(arena, len);
  70         } else {
  71             result->Data = PORT_Alloc(len);
  72         }
  73     }
  74
  75     if (mark) {
  76         PORT_ArenaUnmark(arena, mark);
  77     }
  78     return(result);
  79
  80 loser:
  81     if ( arena != NULL ) {
  82         if (mark) {
  83             PORT_ArenaRelease(arena, mark);
  84         }
  85         if (item != NULL) {
  86             item->Data = NULL;
  87             item->Length = 0;
  88         }
  89     } else {
  90         if (result != NULL) {
  91             SECITEM_FreeItem(result, (item == NULL) ? PR_TRUE : PR_FALSE);
  92         }
  93     }
  94     return(NULL);
  95 }
  96
  97 SECStatus
  98 SECITEM_ReallocItem(PRArenaPool *arena, SECItem *item, unsigned int oldlen,
  99                     unsigned int newlen)
 100 {
 101     PORT_Assert(item != NULL);
 102     if (item == NULL) {
 103         /* XXX Set error.  But to what? */
 104         return SECFailure;
 105     }
 106
 107     /*
 108      * If no old length, degenerate to just plain alloc.
 109      */
 110     if (oldlen == 0) {
 111         PORT_Assert(item->Data == NULL || item->Length == 0);
 112         if (newlen == 0) {
 113             /* Nothing to do.  Weird, but not a failure.  */
 114             return SECSuccess;
 115         }
 116         item->Length = newlen;
 117         if (arena != NULL) {
 118             item->Data = PORT_ArenaAlloc(arena, newlen);
 119         } else {
 120             item->Data = PORT_Alloc(newlen);
 121         }
 122     } else {
 123         if (arena != NULL) {
 124             item->Data = PORT_ArenaGrow(arena, item->Data, oldlen, newlen);
 125         } else {
 126             item->Data = PORT_Realloc(item->Data, newlen);
 127         }
 128     }
 129
 130     if (item->Data == NULL) {
 131         return SECFailure;
 132     }
 133
 134     return SECSuccess;
 135 }
 136
 137 SECComparison
 138 SECITEM_CompareItem(const SECItem *a, const SECItem *b)
 139 {
 140     unsigned m;
 141     SECComparison rv;
 142
 143     m = ( ( a->Length < b->Length ) ? a->Length : b->Length );
 144
 145     rv = (SECComparison) PORT_Memcmp(a->Data, b->Data, m);
 146     if (rv) {
 147         return rv;
 148     }
 149     if (a->Length < b->Length) {
 150         return SECLessThan;
 151     }
 152     if (a->Length == b->Length) {
 153         return SECEqual;
 154     }
 155     return SECGreaterThan;
 156 }
 157
 158 Boolean
 159 SECITEM_ItemsAreEqual(const SECItem *a, const SECItem *b)
 160 {
 161     if (a->Length != b->Length)
 162         return PR_FALSE;
 163     if (!a->Length)
 164         return PR_TRUE;
 165     if (!a->Data || !b->Data) {
 166         /* avoid null pointer crash. */
 167                 return (Boolean)(a->Data == b->Data);
 168     }
 169     return (Boolean)!PORT_Memcmp(a->Data, b->Data, a->Length);
 170 }
 171
 172 SECItem *
 173 SECITEM_DupItem(const SECItem *from)
 174 {
 175     return SECITEM_ArenaDupItem(NULL, from);
 176 }
 177
 178 SECItem *
 179 SECITEM_ArenaDupItem(PRArenaPool *arena, const SECItem *from)
 180 {
 181     SECItem *to;
 182
 183     if ( from == NULL ) {
 184                 return(NULL);
 185     }
 186
 187     if ( arena != NULL ) {
 188                 to = (SECItem *)PORT_ArenaAlloc(arena, sizeof(SECItem));
 189     } else {
 190                 to = (SECItem *)PORT_Alloc(sizeof(SECItem));
 191     }
 192     if ( to == NULL ) {
 193                 return(NULL);
 194     }
 195
 196     if ( arena != NULL ) {
 197                 to->Data = (unsigned char *)PORT_ArenaAlloc(arena, from->Length);
 198     } else {
 199                 to->Data = (unsigned char *)PORT_Alloc(from->Length);
 200     }
 201     if ( to->Data == NULL ) {
 202                 PORT_Free(to);
 203                 return(NULL);
 204     }
 205
 206     to->Length = from->Length;
 207     // to->type = from->type;
 208     if ( to->Length ) {
 209                 PORT_Memcpy(to->Data, from->Data, to->Length);
 210     }
 211
 212     return(to);
 213 }
 214
 215 SECStatus
 216 SECITEM_CopyItem(PRArenaPool *arena, SECItem *to, const SECItem *from)
 217 {
 218     // to->type = from->type;
 219     if (from->Data && from->Length) {
 220         if ( arena ) {
 221             to->Data = (unsigned char*) PORT_ArenaAlloc(arena, from->Length);
 222         } else {
 223             to->Data = (unsigned char*) PORT_Alloc(from->Length);
 224         }
 225
 226         if (!to->Data) {
 227             return SECFailure;
 228         }
 229         PORT_Memcpy(to->Data, from->Data, from->Length);
 230         to->Length = from->Length;
 231     } else {
 232         to->Data = 0;
 233         to->Length = 0;
 234     }
 235     return SECSuccess;
 236 }
 237
 238 void
 239 SECITEM_FreeItem(SECItem *zap, Boolean freeit)
 240 {
 241     if (zap) {
 242         PORT_Free(zap->Data);
 243         zap->Data = 0;
 244         zap->Length = 0;
 245         if (freeit) {
 246             PORT_Free(zap);
 247         }
 248     }
 249 }
 250
 251 void
 252 SECITEM_ZfreeItem(SECItem *zap, Boolean freeit)
 253 {
 254     if (zap) {
 255         PORT_ZFree(zap->Data, zap->Length);
 256         zap->Data = 0;
 257         zap->Length = 0;
 258         if (freeit) {
 259             PORT_ZFree(zap, sizeof(SECItem));
 260         }
 261     }
 262 }
 263
 264
 265 /* these reroutines were taken from pkix oid.c, which is supposed to
 266  * replace this file some day */
 267 /*
 268  * This is the hash function.  We simply XOR the encoded form with
 269  * itself in sizeof(PLHashNumber)-byte chunks.  Improving this
 270  * routine is left as an excercise for the more mathematically
 271  * inclined student.
 272  */
 273 PLHashNumber PR_CALLBACK
 274 SECITEM_Hash ( const void *key)
 275 {
 276     const SECItem *item = (const SECItem *)key;
 277     PLHashNumber rv = 0;
 278
 279     PRUint8 *data = (PRUint8 *)item->Data;
 280     PRUint32 i;
 281     PRUint8 *rvc = (PRUint8 *)&rv;
 282
 283     for( i = 0; i < item->Length; i++ ) {
 284         rvc[ i % sizeof(rv) ] ^= *data;
 285         data++;
 286     }
 287
 288     return rv;
 289 }
 290
 291 /*
 292  * This is the key-compare function.  It simply does a lexical
 293  * comparison on the item data.  This does not result in
 294  * quite the same ordering as the "sequence of numbers" order,
 295  * but heck it's only used internally by the hash table anyway.
 296  */
 297 PRIntn PR_CALLBACK
 298 SECITEM_HashCompare ( const void *k1, const void *k2)
 299 {
 300     const SECItem *i1 = (const SECItem *)k1;
 301     const SECItem *i2 = (const SECItem *)k2;
 302
 303     return SECITEM_ItemsAreEqual(i1,i2);
 304 }