crypto/core_namemap.c

   1 /*
   2  * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include "e_os.h"                /* strcasecmp */
  11 #include "internal/namemap.h"
  12 #include <openssl/lhash.h>
  13 #include "crypto/lhash.h"      /* openssl_lh_strcasehash */
  14
  15 /*-
  16  * The namenum entry
  17  * =================
  18  */
  19 typedef struct {
  20     char *name;
  21     int number;
  22 } NAMENUM_ENTRY;
  23
  24 DEFINE_LHASH_OF(NAMENUM_ENTRY);
  25
  26 /*-
  27  * The namemap itself
  28  * ==================
  29  */
  30
  31 struct ossl_namemap_st {
  32     /* Flags */
  33     unsigned int stored:1; /* If 1, it's stored in a library context */
  34
  35     CRYPTO_RWLOCK *lock;
  36     LHASH_OF(NAMENUM_ENTRY) *namenum;  /* Name->number mapping */
  37     int max_number;                    /* Current max number */
  38 };
  39
  40 /* LHASH callbacks */
  41
  42 static unsigned long namenum_hash(const NAMENUM_ENTRY *n)
  43 {
  44     return openssl_lh_strcasehash(n->name);
  45 }
  46
  47 static int namenum_cmp(const NAMENUM_ENTRY *a, const NAMENUM_ENTRY *b)
  48 {
  49     return strcasecmp(a->name, b->name);
  50 }
  51
  52 static void namenum_free(NAMENUM_ENTRY *n)
  53 {
  54     if (n != NULL)
  55         OPENSSL_free(n->name);
  56     OPENSSL_free(n);
  57 }
  58
  59 /* OPENSSL_CTX_METHOD functions for a namemap stored in a library context */
  60
  61 static void *stored_namemap_new(OPENSSL_CTX *libctx)
  62 {
  63     OSSL_NAMEMAP *namemap = ossl_namemap_new();
  64
  65     if (namemap != NULL)
  66         namemap->stored = 1;
  67
  68     return namemap;
  69 }
  70
  71 static void stored_namemap_free(void *vnamemap)
  72 {
  73     OSSL_NAMEMAP *namemap = vnamemap;
  74
  75     if (namemap != NULL) {
  76         /* Pretend it isn't stored, or ossl_namemap_free() will do nothing */
  77         namemap->stored = 0;
  78         ossl_namemap_free(namemap);
  79     }
  80 }
  81
  82 static const OPENSSL_CTX_METHOD stored_namemap_method = {
  83     stored_namemap_new,
  84     stored_namemap_free,
  85 };
  86
  87 /*-
  88  * API functions
  89  * =============
  90  */
  91
  92 OSSL_NAMEMAP *ossl_namemap_stored(OPENSSL_CTX *libctx)
  93 {
  94     return openssl_ctx_get_data(libctx, OPENSSL_CTX_NAMEMAP_INDEX,
  95                                 &stored_namemap_method);
  96 }
  97
  98 OSSL_NAMEMAP *ossl_namemap_new(void)
  99 {
 100     OSSL_NAMEMAP *namemap;
 101
 102     if ((namemap = OPENSSL_zalloc(sizeof(*namemap))) != NULL
 103         && (namemap->lock = CRYPTO_THREAD_lock_new()) != NULL
 104         && (namemap->namenum =
 105             lh_NAMENUM_ENTRY_new(namenum_hash, namenum_cmp)) != NULL)
 106         return namemap;
 107
 108     ossl_namemap_free(namemap);
 109     return NULL;
 110 }
 111
 112 void ossl_namemap_free(OSSL_NAMEMAP *namemap)
 113 {
 114     if (namemap == NULL || namemap->stored)
 115         return;
 116
 117     lh_NAMENUM_ENTRY_doall(namemap->namenum, namenum_free);
 118     lh_NAMENUM_ENTRY_free(namemap->namenum);
 119
 120     CRYPTO_THREAD_lock_free(namemap->lock);
 121     OPENSSL_free(namemap);
 122 }
 123
 124 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
 125 {
 126     int rv = 0;
 127
 128     CRYPTO_THREAD_read_lock(namemap->lock);
 129     if (namemap->max_number == 0)
 130         rv = 1;
 131     CRYPTO_THREAD_unlock(namemap->lock);
 132
 133     return rv;
 134 }
 135
 136 typedef struct doall_names_data_st {
 137     int number;
 138     void (*fn)(const char *name, void *data);
 139     void *data;
 140 } DOALL_NAMES_DATA;
 141
 142 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 143 {
 144     if (namenum->number == data->number)
 145         data->fn(namenum->name, data->data);
 146 }
 147
 148 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 149
 150 void ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 151                               void (*fn)(const char *name, void *data),
 152                               void *data)
 153 {
 154     DOALL_NAMES_DATA cbdata;
 155
 156     cbdata.number = number;
 157     cbdata.fn = fn;
 158     cbdata.data = data;
 159     CRYPTO_THREAD_read_lock(namemap->lock);
 160     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 161                                             &cbdata);
 162     CRYPTO_THREAD_unlock(namemap->lock);
 163 }
 164
 165 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 166                             const char *name, size_t name_len)
 167 {
 168     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 169     int number = 0;
 170
 171 #ifndef FIPS_MODE
 172     if (namemap == NULL)
 173         namemap = ossl_namemap_stored(NULL);
 174 #endif
 175
 176     if (namemap == NULL)
 177         return 0;
 178
 179     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 180         return 0;
 181     namenum_tmpl.number = 0;
 182     CRYPTO_THREAD_read_lock(namemap->lock);
 183     namenum_entry =
 184         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 185     if (namenum_entry != NULL)
 186         number = namenum_entry->number;
 187     CRYPTO_THREAD_unlock(namemap->lock);
 188     OPENSSL_free(namenum_tmpl.name);
 189
 190     return number;
 191 }
 192
 193 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 194 {
 195     if (name == NULL)
 196         return 0;
 197
 198     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 199 }
 200
 201 struct num2name_data_st {
 202     size_t idx;                  /* Countdown */
 203     const char *name;            /* Result */
 204 };
 205
 206 static void do_num2name(const char *name, void *vdata)
 207 {
 208     struct num2name_data_st *data = vdata;
 209
 210     if (data->idx > 0)
 211         data->idx--;
 212     else if (data->name == NULL)
 213         data->name = name;
 214 }
 215
 216 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 217                                   size_t idx)
 218 {
 219     struct num2name_data_st data;
 220
 221     data.idx = idx;
 222     data.name = NULL;
 223     ossl_namemap_doall_names(namemap, number, do_num2name, &data);
 224     return data.name;
 225 }
 226
 227 int ossl_namemap_add_n(OSSL_NAMEMAP *namemap, int number,
 228                        const char *name, size_t name_len)
 229 {
 230     NAMENUM_ENTRY *namenum = NULL;
 231     int tmp_number;
 232
 233 #ifndef FIPS_MODE
 234     if (namemap == NULL)
 235         namemap = ossl_namemap_stored(NULL);
 236 #endif
 237
 238     if (name == NULL || name_len == 0 || namemap == NULL)
 239         return 0;
 240
 241     if ((tmp_number = ossl_namemap_name2num_n(namemap, name, name_len)) != 0)
 242         return tmp_number;       /* Pretend success */
 243
 244     CRYPTO_THREAD_write_lock(namemap->lock);
 245
 246     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 247         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 248         goto err;
 249
 250     namenum->number = tmp_number =
 251         number != 0 ? number : ++namemap->max_number;
 252     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 253
 254     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 255         goto err;
 256
 257     CRYPTO_THREAD_unlock(namemap->lock);
 258
 259     return tmp_number;
 260
 261  err:
 262     namenum_free(namenum);
 263
 264     CRYPTO_THREAD_unlock(namemap->lock);
 265     return 0;
 266 }
 267
 268 int ossl_namemap_add(OSSL_NAMEMAP *namemap, int number, const char *name)
 269 {
 270     if (name == NULL)
 271         return 0;
 272
 273     return ossl_namemap_add_n(namemap, number, name, strlen(name));
 274 }