crypto/engine/eng_ctrl.c

   1 /* ====================================================================
   2  * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  *
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in
  13  *    the documentation and/or other materials provided with the
  14  *    distribution.
  15  *
  16  * 3. All advertising materials mentioning features or use of this
  17  *    software must display the following acknowledgment:
  18  *    "This product includes software developed by the OpenSSL Project
  19  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  20  *
  21  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  22  *    endorse or promote products derived from this software without
  23  *    prior written permission. For written permission, please contact
  24  *    licensing@OpenSSL.org.
  25  *
  26  * 5. Products derived from this software may not be called "OpenSSL"
  27  *    nor may "OpenSSL" appear in their names without prior written
  28  *    permission of the OpenSSL Project.
  29  *
  30  * 6. Redistributions of any form whatsoever must retain the following
  31  *    acknowledgment:
  32  *    "This product includes software developed by the OpenSSL Project
  33  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  34  *
  35  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  36  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  38  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  41  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  42  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  44  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  45  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  46  * OF THE POSSIBILITY OF SUCH DAMAGE.
  47  * ====================================================================
  48  *
  49  * This product includes cryptographic software written by Eric Young
  50  * (eay@cryptsoft.com).  This product includes software written by Tim
  51  * Hudson (tjh@cryptsoft.com).
  52  *
  53  */
  54
  55 #include "eng_int.h"
  56
  57 /*
  58  * When querying a ENGINE-specific control command's 'description', this
  59  * string is used if the ENGINE_CMD_DEFN has cmd_desc set to NULL.
  60  */
  61 static const char *int_no_description = "";
  62
  63 /*
  64  * These internal functions handle 'CMD'-related control commands when the
  65  * ENGINE in question has asked us to take care of it (ie. the ENGINE did not
  66  * set the ENGINE_FLAGS_MANUAL_CMD_CTRL flag.
  67  */
  68
  69 static int int_ctrl_cmd_is_null(const ENGINE_CMD_DEFN *defn)
  70 {
  71     if ((defn->cmd_num == 0) || (defn->cmd_name == NULL))
  72         return 1;
  73     return 0;
  74 }
  75
  76 static int int_ctrl_cmd_by_name(const ENGINE_CMD_DEFN *defn, const char *s)
  77 {
  78     int idx = 0;
  79     while (!int_ctrl_cmd_is_null(defn) && (strcmp(defn->cmd_name, s) != 0)) {
  80         idx++;
  81         defn++;
  82     }
  83     if (int_ctrl_cmd_is_null(defn))
  84         /* The given name wasn't found */
  85         return -1;
  86     return idx;
  87 }
  88
  89 static int int_ctrl_cmd_by_num(const ENGINE_CMD_DEFN *defn, unsigned int num)
  90 {
  91     int idx = 0;
  92     /*
  93      * NB: It is stipulated that 'cmd_defn' lists are ordered by cmd_num. So
  94      * our searches don't need to take any longer than necessary.
  95      */
  96     while (!int_ctrl_cmd_is_null(defn) && (defn->cmd_num < num)) {
  97         idx++;
  98         defn++;
  99     }
 100     if (defn->cmd_num == num)
 101         return idx;
 102     /* The given cmd_num wasn't found */
 103     return -1;
 104 }
 105
 106 static int int_ctrl_helper(ENGINE *e, int cmd, long i, void *p,
 107                            void (*f) (void))
 108 {
 109     int idx;
 110     char *s = (char *)p;
 111     /* Take care of the easy one first (eg. it requires no searches) */
 112     if (cmd == ENGINE_CTRL_GET_FIRST_CMD_TYPE) {
 113         if ((e->cmd_defns == NULL) || int_ctrl_cmd_is_null(e->cmd_defns))
 114             return 0;
 115         return e->cmd_defns->cmd_num;
 116     }
 117     /* One or two commands require that "p" be a valid string buffer */
 118     if ((cmd == ENGINE_CTRL_GET_CMD_FROM_NAME) ||
 119         (cmd == ENGINE_CTRL_GET_NAME_FROM_CMD) ||
 120         (cmd == ENGINE_CTRL_GET_DESC_FROM_CMD)) {
 121         if (s == NULL) {
 122             ENGINEerr(ENGINE_F_INT_CTRL_HELPER, ERR_R_PASSED_NULL_PARAMETER);
 123             return -1;
 124         }
 125     }
 126     /* Now handle cmd_name -> cmd_num conversion */
 127     if (cmd == ENGINE_CTRL_GET_CMD_FROM_NAME) {
 128         if ((e->cmd_defns == NULL)
 129             || ((idx = int_ctrl_cmd_by_name(e->cmd_defns, s)) < 0)) {
 130             ENGINEerr(ENGINE_F_INT_CTRL_HELPER, ENGINE_R_INVALID_CMD_NAME);
 131             return -1;
 132         }
 133         return e->cmd_defns[idx].cmd_num;
 134     }
 135     /*
 136      * For the rest of the commands, the 'long' argument must specify a valid
 137      * command number - so we need to conduct a search.
 138      */
 139     if ((e->cmd_defns == NULL) || ((idx = int_ctrl_cmd_by_num(e->cmd_defns,
 140                                                               (unsigned int)
 141                                                               i)) < 0)) {
 142         ENGINEerr(ENGINE_F_INT_CTRL_HELPER, ENGINE_R_INVALID_CMD_NUMBER);
 143         return -1;
 144     }
 145     /* Now the logic splits depending on command type */
 146     switch (cmd) {
 147     case ENGINE_CTRL_GET_NEXT_CMD_TYPE:
 148         idx++;
 149         if (int_ctrl_cmd_is_null(e->cmd_defns + idx))
 150             /* end-of-list */
 151             return 0;
 152         else
 153             return e->cmd_defns[idx].cmd_num;
 154     case ENGINE_CTRL_GET_NAME_LEN_FROM_CMD:
 155         return strlen(e->cmd_defns[idx].cmd_name);
 156     case ENGINE_CTRL_GET_NAME_FROM_CMD:
 157         return BIO_snprintf(s, strlen(e->cmd_defns[idx].cmd_name) + 1,
 158                             "%s", e->cmd_defns[idx].cmd_name);
 159     case ENGINE_CTRL_GET_DESC_LEN_FROM_CMD:
 160         if (e->cmd_defns[idx].cmd_desc)
 161             return strlen(e->cmd_defns[idx].cmd_desc);
 162         return strlen(int_no_description);
 163     case ENGINE_CTRL_GET_DESC_FROM_CMD:
 164         if (e->cmd_defns[idx].cmd_desc)
 165             return BIO_snprintf(s,
 166                                 strlen(e->cmd_defns[idx].cmd_desc) + 1,
 167                                 "%s", e->cmd_defns[idx].cmd_desc);
 168         return BIO_snprintf(s, strlen(int_no_description) + 1, "%s",
 169                             int_no_description);
 170     case ENGINE_CTRL_GET_CMD_FLAGS:
 171         return e->cmd_defns[idx].cmd_flags;
 172     }
 173     /* Shouldn't really be here ... */
 174     ENGINEerr(ENGINE_F_INT_CTRL_HELPER, ENGINE_R_INTERNAL_LIST_ERROR);
 175     return -1;
 176 }
 177
 178 int ENGINE_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f) (void))
 179 {
 180     int ctrl_exists, ref_exists;
 181     if (e == NULL) {
 182         ENGINEerr(ENGINE_F_ENGINE_CTRL, ERR_R_PASSED_NULL_PARAMETER);
 183         return 0;
 184     }
 185     CRYPTO_THREAD_write_lock(global_engine_lock);
 186     ref_exists = ((e->struct_ref > 0) ? 1 : 0);
 187     CRYPTO_THREAD_unlock(global_engine_lock);
 188     ctrl_exists = ((e->ctrl == NULL) ? 0 : 1);
 189     if (!ref_exists) {
 190         ENGINEerr(ENGINE_F_ENGINE_CTRL, ENGINE_R_NO_REFERENCE);
 191         return 0;
 192     }
 193     /*
 194      * Intercept any "root-level" commands before trying to hand them on to
 195      * ctrl() handlers.
 196      */
 197     switch (cmd) {
 198     case ENGINE_CTRL_HAS_CTRL_FUNCTION:
 199         return ctrl_exists;
 200     case ENGINE_CTRL_GET_FIRST_CMD_TYPE:
 201     case ENGINE_CTRL_GET_NEXT_CMD_TYPE:
 202     case ENGINE_CTRL_GET_CMD_FROM_NAME:
 203     case ENGINE_CTRL_GET_NAME_LEN_FROM_CMD:
 204     case ENGINE_CTRL_GET_NAME_FROM_CMD:
 205     case ENGINE_CTRL_GET_DESC_LEN_FROM_CMD:
 206     case ENGINE_CTRL_GET_DESC_FROM_CMD:
 207     case ENGINE_CTRL_GET_CMD_FLAGS:
 208         if (ctrl_exists && !(e->flags & ENGINE_FLAGS_MANUAL_CMD_CTRL))
 209             return int_ctrl_helper(e, cmd, i, p, f);
 210         if (!ctrl_exists) {
 211             ENGINEerr(ENGINE_F_ENGINE_CTRL, ENGINE_R_NO_CONTROL_FUNCTION);
 212             /*
 213              * For these cmd-related functions, failure is indicated by a -1
 214              * return value (because 0 is used as a valid return in some
 215              * places).
 216              */
 217             return -1;
 218         }
 219     default:
 220         break;
 221     }
 222     /* Anything else requires a ctrl() handler to exist. */
 223     if (!ctrl_exists) {
 224         ENGINEerr(ENGINE_F_ENGINE_CTRL, ENGINE_R_NO_CONTROL_FUNCTION);
 225         return 0;
 226     }
 227     return e->ctrl(e, cmd, i, p, f);
 228 }
 229
 230 int ENGINE_cmd_is_executable(ENGINE *e, int cmd)
 231 {
 232     int flags;
 233     if ((flags =
 234          ENGINE_ctrl(e, ENGINE_CTRL_GET_CMD_FLAGS, cmd, NULL, NULL)) < 0) {
 235         ENGINEerr(ENGINE_F_ENGINE_CMD_IS_EXECUTABLE,
 236                   ENGINE_R_INVALID_CMD_NUMBER);
 237         return 0;
 238     }
 239     if (!(flags & ENGINE_CMD_FLAG_NO_INPUT) &&
 240         !(flags & ENGINE_CMD_FLAG_NUMERIC) &&
 241         !(flags & ENGINE_CMD_FLAG_STRING))
 242         return 0;
 243     return 1;
 244 }
 245
 246 int ENGINE_ctrl_cmd(ENGINE *e, const char *cmd_name,
 247                     long i, void *p, void (*f) (void), int cmd_optional)
 248 {
 249     int num;
 250
 251     if ((e == NULL) || (cmd_name == NULL)) {
 252         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD, ERR_R_PASSED_NULL_PARAMETER);
 253         return 0;
 254     }
 255     if ((e->ctrl == NULL) || ((num = ENGINE_ctrl(e,
 256                                                  ENGINE_CTRL_GET_CMD_FROM_NAME,
 257                                                  0, (void *)cmd_name,
 258                                                  NULL)) <= 0)) {
 259         /*
 260          * If the command didn't *have* to be supported, we fake success.
 261          * This allows certain settings to be specified for multiple ENGINEs
 262          * and only require a change of ENGINE id (without having to
 263          * selectively apply settings). Eg. changing from a hardware device
 264          * back to the regular software ENGINE without editing the config
 265          * file, etc.
 266          */
 267         if (cmd_optional) {
 268             ERR_clear_error();
 269             return 1;
 270         }
 271         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD, ENGINE_R_INVALID_CMD_NAME);
 272         return 0;
 273     }
 274     /*
 275      * Force the result of the control command to 0 or 1, for the reasons
 276      * mentioned before.
 277      */
 278     if (ENGINE_ctrl(e, num, i, p, f) > 0)
 279         return 1;
 280     return 0;
 281 }
 282
 283 int ENGINE_ctrl_cmd_string(ENGINE *e, const char *cmd_name, const char *arg,
 284                            int cmd_optional)
 285 {
 286     int num, flags;
 287     long l;
 288     char *ptr;
 289     if ((e == NULL) || (cmd_name == NULL)) {
 290         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 291                   ERR_R_PASSED_NULL_PARAMETER);
 292         return 0;
 293     }
 294     if ((e->ctrl == NULL) || ((num = ENGINE_ctrl(e,
 295                                                  ENGINE_CTRL_GET_CMD_FROM_NAME,
 296                                                  0, (void *)cmd_name,
 297                                                  NULL)) <= 0)) {
 298         /*
 299          * If the command didn't *have* to be supported, we fake success.
 300          * This allows certain settings to be specified for multiple ENGINEs
 301          * and only require a change of ENGINE id (without having to
 302          * selectively apply settings). Eg. changing from a hardware device
 303          * back to the regular software ENGINE without editing the config
 304          * file, etc.
 305          */
 306         if (cmd_optional) {
 307             ERR_clear_error();
 308             return 1;
 309         }
 310         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING, ENGINE_R_INVALID_CMD_NAME);
 311         return 0;
 312     }
 313     if (!ENGINE_cmd_is_executable(e, num)) {
 314         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 315                   ENGINE_R_CMD_NOT_EXECUTABLE);
 316         return 0;
 317     }
 318     if ((flags =
 319          ENGINE_ctrl(e, ENGINE_CTRL_GET_CMD_FLAGS, num, NULL, NULL)) < 0) {
 320         /*
 321          * Shouldn't happen, given that ENGINE_cmd_is_executable() returned
 322          * success.
 323          */
 324         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 325                   ENGINE_R_INTERNAL_LIST_ERROR);
 326         return 0;
 327     }
 328     /*
 329      * If the command takes no input, there must be no input. And vice versa.
 330      */
 331     if (flags & ENGINE_CMD_FLAG_NO_INPUT) {
 332         if (arg != NULL) {
 333             ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 334                       ENGINE_R_COMMAND_TAKES_NO_INPUT);
 335             return 0;
 336         }
 337         /*
 338          * We deliberately force the result of ENGINE_ctrl() to 0 or 1 rather
 339          * than returning it as "return data". This is to ensure usage of
 340          * these commands is consistent across applications and that certain
 341          * applications don't understand it one way, and others another.
 342          */
 343         if (ENGINE_ctrl(e, num, 0, (void *)arg, NULL) > 0)
 344             return 1;
 345         return 0;
 346     }
 347     /* So, we require input */
 348     if (arg == NULL) {
 349         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 350                   ENGINE_R_COMMAND_TAKES_INPUT);
 351         return 0;
 352     }
 353     /* If it takes string input, that's easy */
 354     if (flags & ENGINE_CMD_FLAG_STRING) {
 355         /* Same explanation as above */
 356         if (ENGINE_ctrl(e, num, 0, (void *)arg, NULL) > 0)
 357             return 1;
 358         return 0;
 359     }
 360     /*
 361      * If it doesn't take numeric either, then it is unsupported for use in a
 362      * config-setting situation, which is what this function is for. This
 363      * should never happen though, because ENGINE_cmd_is_executable() was
 364      * used.
 365      */
 366     if (!(flags & ENGINE_CMD_FLAG_NUMERIC)) {
 367         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 368                   ENGINE_R_INTERNAL_LIST_ERROR);
 369         return 0;
 370     }
 371     l = strtol(arg, &ptr, 10);
 372     if ((arg == ptr) || (*ptr != '\0')) {
 373         ENGINEerr(ENGINE_F_ENGINE_CTRL_CMD_STRING,
 374                   ENGINE_R_ARGUMENT_IS_NOT_A_NUMBER);
 375         return 0;
 376     }
 377     /*
 378      * Force the result of the control command to 0 or 1, for the reasons
 379      * mentioned before.
 380      */
 381     if (ENGINE_ctrl(e, num, l, NULL, NULL) > 0)
 382         return 1;
 383     return 0;
 384 }