crypto/pqueue/pqueue.c

   1 /* crypto/pqueue/pqueue.c */
   2 /*
   3  * DTLS implementation written by Nagendra Modadugu
   4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    openssl-core@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 #include "internal/cryptlib.h"
  61 #include <openssl/bn.h>
  62 #include <openssl/pqueue.h>
  63
  64 typedef struct _pqueue {
  65     pitem *items;
  66     int count;
  67 } pqueue_s;
  68
  69 pitem *pitem_new(unsigned char *prio64be, void *data)
  70 {
  71     pitem *item = OPENSSL_malloc(sizeof(*item));
  72     if (item == NULL)
  73         return NULL;
  74
  75     memcpy(item->priority, prio64be, sizeof(item->priority));
  76
  77     item->data = data;
  78     item->next = NULL;
  79
  80     return item;
  81 }
  82
  83 void pitem_free(pitem *item)
  84 {
  85     OPENSSL_free(item);
  86 }
  87
  88 pqueue_s *pqueue_new()
  89 {
  90     pqueue_s *pq = OPENSSL_malloc(sizeof(*pq));
  91     if (pq == NULL)
  92         return NULL;
  93
  94     memset(pq, 0, sizeof(*pq));
  95     return pq;
  96 }
  97
  98 void pqueue_free(pqueue_s *pq)
  99 {
 100     OPENSSL_free(pq);
 101 }
 102
 103 pitem *pqueue_insert(pqueue_s *pq, pitem *item)
 104 {
 105     pitem *curr, *next;
 106
 107     if (pq->items == NULL) {
 108         pq->items = item;
 109         return item;
 110     }
 111
 112     for (curr = NULL, next = pq->items;
 113          next != NULL; curr = next, next = next->next) {
 114         /*
 115          * we can compare 64-bit value in big-endian encoding with memcmp:-)
 116          */
 117         int cmp = memcmp(next->priority, item->priority, 8);
 118         if (cmp > 0) {          /* next > item */
 119             item->next = next;
 120
 121             if (curr == NULL)
 122                 pq->items = item;
 123             else
 124                 curr->next = item;
 125
 126             return item;
 127         }
 128
 129         else if (cmp == 0)      /* duplicates not allowed */
 130             return NULL;
 131     }
 132
 133     item->next = NULL;
 134     curr->next = item;
 135
 136     return item;
 137 }
 138
 139 pitem *pqueue_peek(pqueue_s *pq)
 140 {
 141     return pq->items;
 142 }
 143
 144 pitem *pqueue_pop(pqueue_s *pq)
 145 {
 146     pitem *item = pq->items;
 147
 148     if (pq->items != NULL)
 149         pq->items = pq->items->next;
 150
 151     return item;
 152 }
 153
 154 pitem *pqueue_find(pqueue_s *pq, unsigned char *prio64be)
 155 {
 156     pitem *next;
 157     pitem *found = NULL;
 158
 159     if (pq->items == NULL)
 160         return NULL;
 161
 162     for (next = pq->items; next->next != NULL; next = next->next) {
 163         if (memcmp(next->priority, prio64be, 8) == 0) {
 164             found = next;
 165             break;
 166         }
 167     }
 168
 169     /* check the one last node */
 170     if (memcmp(next->priority, prio64be, 8) == 0)
 171         found = next;
 172
 173     if (!found)
 174         return NULL;
 175
 176     return found;
 177 }
 178
 179 void pqueue_print(pqueue_s *pq)
 180 {
 181     pitem *item = pq->items;
 182
 183     while (item != NULL) {
 184         printf("item\t%02x%02x%02x%02x%02x%02x%02x%02x\n",
 185                item->priority[0], item->priority[1],
 186                item->priority[2], item->priority[3],
 187                item->priority[4], item->priority[5],
 188                item->priority[6], item->priority[7]);
 189         item = item->next;
 190     }
 191 }
 192
 193 pitem *pqueue_iterator(pqueue_s *pq)
 194 {
 195     return pqueue_peek(pq);
 196 }
 197
 198 pitem *pqueue_next(pitem **item)
 199 {
 200     pitem *ret;
 201
 202     if (item == NULL || *item == NULL)
 203         return NULL;
 204
 205     /* *item != NULL */
 206     ret = *item;
 207     *item = (*item)->next;
 208
 209     return ret;
 210 }
 211
 212 int pqueue_size(pqueue_s *pq)
 213 {
 214     pitem *item = pq->items;
 215     int count = 0;
 216
 217     while (item != NULL) {
 218         count++;
 219         item = item->next;
 220     }
 221     return count;
 222 }