crypto/property/property_string.c

   1 /*
   2  * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright (c) 2019, Oracle and/or its affiliates.  All rights reserved.
   4  *
   5  * Licensed under the Apache License 2.0 (the "License").  You may not use
   6  * this file except in compliance with the License.  You can obtain a copy
   7  * in the file LICENSE in the source distribution or at
   8  * https://www.openssl.org/source/license.html
   9  */
  10
  11 #include <string.h>
  12 #include <openssl/crypto.h>
  13 #include <openssl/lhash.h>
  14 #include "crypto/lhash.h"
  15 #include "property_local.h"
  16
  17 /*
  18  * Property strings are a consolidation of all strings seen by the property
  19  * subsystem.  There are two name spaces to keep property names separate from
  20  * property values (numeric values are not expected to be cached however).
  21  * They allow a rapid conversion from a string to a unique index and any
  22  * subsequent string comparison can be done via an integer compare.
  23  *
  24  * This implementation uses OpenSSL's standard hash table.  There are more
  25  * space and time efficient algorithms if this becomes a bottleneck.
  26  */
  27
  28 typedef struct {
  29     const char *s;
  30     OSSL_PROPERTY_IDX idx;
  31     char body[1];
  32 } PROPERTY_STRING;
  33
  34 DEFINE_LHASH_OF(PROPERTY_STRING);
  35 typedef LHASH_OF(PROPERTY_STRING) PROP_TABLE;
  36
  37 typedef struct {
  38     PROP_TABLE *prop_names;
  39     PROP_TABLE *prop_values;
  40     OSSL_PROPERTY_IDX prop_name_idx;
  41     OSSL_PROPERTY_IDX prop_value_idx;
  42 } PROPERTY_STRING_DATA;
  43
  44 static unsigned long property_hash(const PROPERTY_STRING *a)
  45 {
  46     return OPENSSL_LH_strhash(a->s);
  47 }
  48
  49 static int property_cmp(const PROPERTY_STRING *a, const PROPERTY_STRING *b)
  50 {
  51     return strcmp(a->s, b->s);
  52 }
  53
  54 static void property_free(PROPERTY_STRING *ps)
  55 {
  56     OPENSSL_free(ps);
  57 }
  58
  59 static void property_table_free(PROP_TABLE **pt)
  60 {
  61     PROP_TABLE *t = *pt;
  62
  63     if (t != NULL) {
  64         lh_PROPERTY_STRING_doall(t, &property_free);
  65         lh_PROPERTY_STRING_free(t);
  66         *pt = NULL;
  67     }
  68 }
  69
  70 static void property_string_data_free(void *vpropdata)
  71 {
  72     PROPERTY_STRING_DATA *propdata = vpropdata;
  73
  74     if (propdata == NULL)
  75         return;
  76
  77     property_table_free(&propdata->prop_names);
  78     property_table_free(&propdata->prop_values);
  79     propdata->prop_name_idx = propdata->prop_value_idx = 0;
  80
  81     OPENSSL_free(propdata);
  82 }
  83
  84 static void *property_string_data_new(OSSL_LIB_CTX *ctx) {
  85     PROPERTY_STRING_DATA *propdata = OPENSSL_zalloc(sizeof(*propdata));
  86
  87     if (propdata == NULL)
  88         return NULL;
  89
  90     propdata->prop_names = lh_PROPERTY_STRING_new(&property_hash,
  91                                                   &property_cmp);
  92     if (propdata->prop_names == NULL)
  93         goto err;
  94
  95     propdata->prop_values = lh_PROPERTY_STRING_new(&property_hash,
  96                                                    &property_cmp);
  97     if (propdata->prop_values == NULL)
  98         goto err;
  99
 100     return propdata;
 101
 102 err:
 103     property_string_data_free(propdata);
 104     return NULL;
 105 }
 106
 107 static const OSSL_LIB_CTX_METHOD property_string_data_method = {
 108     property_string_data_new,
 109     property_string_data_free,
 110 };
 111
 112 static PROPERTY_STRING *new_property_string(const char *s,
 113                                             OSSL_PROPERTY_IDX *pidx)
 114 {
 115     const size_t l = strlen(s);
 116     PROPERTY_STRING *ps = OPENSSL_malloc(sizeof(*ps) + l);
 117
 118     if (ps != NULL) {
 119         memcpy(ps->body, s, l + 1);
 120         ps->s = ps->body;
 121         ps->idx = ++*pidx;
 122         if (ps->idx == 0) {
 123             OPENSSL_free(ps);
 124             return NULL;
 125         }
 126     }
 127     return ps;
 128 }
 129
 130 static OSSL_PROPERTY_IDX ossl_property_string(PROP_TABLE *t,
 131                                               OSSL_PROPERTY_IDX *pidx,
 132                                               const char *s)
 133 {
 134     PROPERTY_STRING p, *ps, *ps_new;
 135
 136     p.s = s;
 137     ps = lh_PROPERTY_STRING_retrieve(t, &p);
 138     if (ps == NULL && pidx != NULL)
 139         if ((ps_new = new_property_string(s, pidx)) != NULL) {
 140             lh_PROPERTY_STRING_insert(t, ps_new);
 141             if (lh_PROPERTY_STRING_error(t)) {
 142                 property_free(ps_new);
 143                 return 0;
 144             }
 145             ps = ps_new;
 146         }
 147     return ps != NULL ? ps->idx : 0;
 148 }
 149
 150 OSSL_PROPERTY_IDX ossl_property_name(OSSL_LIB_CTX *ctx, const char *s,
 151                                      int create)
 152 {
 153     PROPERTY_STRING_DATA *propdata
 154         = ossl_lib_ctx_get_data(ctx, OSSL_LIB_CTX_PROPERTY_STRING_INDEX,
 155                                 &property_string_data_method);
 156
 157     if (propdata == NULL)
 158         return 0;
 159     return ossl_property_string(propdata->prop_names,
 160                                 create ? &propdata->prop_name_idx : NULL,
 161                                 s);
 162 }
 163
 164 OSSL_PROPERTY_IDX ossl_property_value(OSSL_LIB_CTX *ctx, const char *s,
 165                                       int create)
 166 {
 167     PROPERTY_STRING_DATA *propdata
 168         = ossl_lib_ctx_get_data(ctx, OSSL_LIB_CTX_PROPERTY_STRING_INDEX,
 169                                 &property_string_data_method);
 170
 171     if (propdata == NULL)
 172         return 0;
 173     return ossl_property_string(propdata->prop_values,
 174                                 create ? &propdata->prop_value_idx : NULL,
 175                                 s);
 176 }