conf_mod.c

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/* conf_mod.c */
/* Written by Stephen Henson ([email protected]) for the OpenSSL
 * project 2001.
 */
/* ====================================================================
 * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    [email protected].
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * ([email protected]).  This product includes software written by Tim
 * Hudson ([email protected]).
 *
 */

#include <stdio.h>
#include <ctype.h>
#include <openssl/crypto.h>
#include "cryptlib.h"
#include <openssl/conf.h>
#include <openssl/dso.h>
#include <openssl/x509.h>


#define DSO_mod_init_name "OPENSSL_init"
#define DSO_mod_finish_name "OPENSSL_finish"


/* This structure contains a data about supported modules.
 * entries in this table correspond to either dynamic or
 * static modules.
 */

struct conf_module_st
    {
    /* DSO of this module or NULL if static */
    DSO *dso;
    /* Name of the module */
    char *name;
    /* Init function */
    conf_init_func *init; 
    /* Finish function */
    conf_finish_func *finish;
    /* Number of successfully initialized modules */
    int links;
    void *usr_data;
    };


/* This structure contains information about modules that have been
 * successfully initialized. There may be more than one entry for a
 * given module.
 */

struct conf_imodule_st
    {
    CONF_MODULE *pmod;
    char *name;
    char *value;
    unsigned long flags;
    void *usr_data;
    };

static STACK_OF(CONF_MODULE) *supported_modules = NULL;
static STACK_OF(CONF_IMODULE) *initialized_modules = NULL;

static void module_free(CONF_MODULE *md);
static void module_finish(CONF_IMODULE *imod);
static int module_run(const CONF *cnf, char *name, char *value,
                      unsigned long flags);
static CONF_MODULE *module_add(DSO *dso, const char *name,
            conf_init_func *ifunc, conf_finish_func *ffunc);
static CONF_MODULE *module_find(char *name);
static int module_init(CONF_MODULE *pmod, char *name, char *value,
                       const CONF *cnf);
static CONF_MODULE *module_load_dso(const CONF *cnf, char *name, char *value,
                                    unsigned long flags);

/* Main function: load modules from a CONF structure */

int CONF_modules_load(const CONF *cnf, const char *appname,
              unsigned long flags)
    {
    STACK_OF(CONF_VALUE) *values;
    CONF_VALUE *vl;
    char *vsection = NULL;

    int ret, i;

    if (!cnf)
        return 1;

    if (appname)
        vsection = NCONF_get_string(cnf, NULL, appname);

    if (!appname || (!vsection && (flags & CONF_MFLAGS_DEFAULT_SECTION)))
        vsection = NCONF_get_string(cnf, NULL, "openssl_conf");

    if (!vsection)
        {
        ERR_clear_error();
        return 1;
        }

    values = NCONF_get_section(cnf, vsection);

    if (!values)
        return 0;

    for (i = 0; i < sk_CONF_VALUE_num(values); i++)
        {
        vl = sk_CONF_VALUE_value(values, i);
        ret = module_run(cnf, vl->name, vl->value, flags);
        if (ret <= 0)
            if(!(flags & CONF_MFLAGS_IGNORE_ERRORS))
                return ret;
        }

    return 1;

    }

int CONF_modules_load_file(const char *filename, const char *appname,
               unsigned long flags)
    {
    char *file = NULL;
    CONF *conf = NULL;
    int ret = 0;
    conf = NCONF_new(NULL);
    if (!conf)
        goto err;

    if (filename == NULL)
        {
        file = CONF_get1_default_config_file();
        if (!file)
            goto err;
        }
    else
        file = (char *)filename;

    if (NCONF_load(conf, file, NULL) <= 0)
        {
        if ((flags & CONF_MFLAGS_IGNORE_MISSING_FILE) &&
          (ERR_GET_REASON(ERR_peek_last_error()) == CONF_R_NO_SUCH_FILE))
            {
            ERR_clear_error();
            ret = 1;
            }
        goto err;
        }

    ret = CONF_modules_load(conf, appname, flags);

    err:
    if (filename == NULL)
        OPENSSL_free(file);
    NCONF_free(conf);

    return ret;
    }

static int module_run(const CONF *cnf, char *name, char *value,
              unsigned long flags)
    {
    CONF_MODULE *md;
    int ret;

    md = module_find(name);

    /* Module not found: try to load DSO */
    if (!md && !(flags & CONF_MFLAGS_NO_DSO))
        md = module_load_dso(cnf, name, value, flags);

    if (!md)
        {
        if (!(flags & CONF_MFLAGS_SILENT))
            {
            CONFerr(CONF_F_MODULE_RUN, CONF_R_UNKNOWN_MODULE_NAME);
            ERR_add_error_data(2, "module=", name);
            }
        return -1;
        }

    ret = module_init(md, name, value, cnf);

    if (ret <= 0)
        {
        if (!(flags & CONF_MFLAGS_SILENT))
            {
            char rcode[DECIMAL_SIZE(ret)+1];
            CONFerr(CONF_F_MODULE_RUN, CONF_R_MODULE_INITIALIZATION_ERROR);
            BIO_snprintf(rcode, sizeof rcode, "%-8d", ret);
            ERR_add_error_data(6, "module=", name, ", value=", value, ", retcode=", rcode);
            }
        }

    return ret;
    }

/* Load a module from a DSO */
static CONF_MODULE *module_load_dso(const CONF *cnf, char *name, char *value,
                    unsigned long flags)
    {
    DSO *dso = NULL;
    conf_init_func *ifunc;
    conf_finish_func *ffunc;
    char *path = NULL;
    int errcode = 0;
    CONF_MODULE *md;
    /* Look for alternative path in module section */
    path = NCONF_get_string(cnf, value, "path");
    if (!path)
        {
        ERR_clear_error();
        path = name;
        }
    dso = DSO_load(NULL, path, NULL, 0);
    if (!dso)
        {
        errcode = CONF_R_ERROR_LOADING_DSO;
        goto err;
        }
        ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
    if (!ifunc)
        {
        errcode = CONF_R_MISSING_INIT_FUNCTION;
        goto err;
        }
        ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
    /* All OK, add module */
    md = module_add(dso, name, ifunc, ffunc);

    if (!md)
        goto err;

    return md;

    err:
    if (dso)
        DSO_free(dso);
    CONFerr(CONF_F_MODULE_LOAD_DSO, errcode);
    ERR_add_error_data(4, "module=", name, ", path=", path);
    return NULL;
    }

/* add module to list */
static CONF_MODULE *module_add(DSO *dso, const char *name,
                   conf_init_func *ifunc, conf_finish_func *ffunc)
    {
    CONF_MODULE *tmod = NULL;
    if (supported_modules == NULL)
        supported_modules = sk_CONF_MODULE_new_null();
    if (supported_modules == NULL)
        return NULL;
    tmod = OPENSSL_malloc(sizeof(CONF_MODULE));
    if (tmod == NULL)
        return NULL;

    tmod->dso = dso;
    tmod->name = BUF_strdup(name);
    tmod->init = ifunc;
    tmod->finish = ffunc;
    tmod->links = 0;

    if (!sk_CONF_MODULE_push(supported_modules, tmod))
        {
        OPENSSL_free(tmod);
        return NULL;
        }

    return tmod;
    }

/* Find a module from the list. We allow module names of the
 * form modname.XXXX to just search for modname to allow the
 * same module to be initialized more than once.
 */

static CONF_MODULE *module_find(char *name)
    {
    CONF_MODULE *tmod;
    int i, nchar;
    char *p;
    p = strrchr(name, '.');

    if (p)
        nchar = p - name;
    else 
        nchar = strlen(name);

    for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++)
        {
        tmod = sk_CONF_MODULE_value(supported_modules, i);
        if (!strncmp(tmod->name, name, nchar))
            return tmod;
        }

    return NULL;

    }

/* initialize a module */
static int module_init(CONF_MODULE *pmod, char *name, char *value,
               const CONF *cnf)
    {
    int ret = 1;
    int init_called = 0;
    CONF_IMODULE *imod = NULL;

    /* Otherwise add initialized module to list */
    imod = OPENSSL_malloc(sizeof(CONF_IMODULE));
    if (!imod)
        goto err;

    imod->pmod = pmod;
    imod->name = BUF_strdup(name);
    imod->value = BUF_strdup(value);
    imod->usr_data = NULL;

    if (!imod->name || !imod->value)
        goto memerr;

    /* Try to initialize module */
    if(pmod->init)
        {
        ret = pmod->init(imod, cnf);
        init_called = 1;
        /* Error occurred, exit */
        if (ret <= 0)
            goto err;
        }

    if (initialized_modules == NULL)
        {
        initialized_modules = sk_CONF_IMODULE_new_null();
        if (!initialized_modules)
            {
            CONFerr(CONF_F_MODULE_INIT, ERR_R_MALLOC_FAILURE);
            goto err;
            }
        }

    if (!sk_CONF_IMODULE_push(initialized_modules, imod))
        {
        CONFerr(CONF_F_MODULE_INIT, ERR_R_MALLOC_FAILURE);
        goto err;
        }

    pmod->links++;

    return ret;

    err:

    /* We've started the module so we'd better finish it */
    if (pmod->finish && init_called)
        pmod->finish(imod);

    memerr:
    if (imod)
        {
        if (imod->name)
            OPENSSL_free(imod->name);
        if (imod->value)
            OPENSSL_free(imod->value);
        OPENSSL_free(imod);
        }

    return -1;

    }

/* Unload any dynamic modules that have a link count of zero:
 * i.e. have no active initialized modules. If 'all' is set
 * then all modules are unloaded including static ones.
 */

void CONF_modules_unload(int all)
    {
    int i;
    CONF_MODULE *md;
    CONF_modules_finish();
    /* unload modules in reverse order */
    for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--)
        {
        md = sk_CONF_MODULE_value(supported_modules, i);
        /* If static or in use and 'all' not set ignore it */
        if (((md->links > 0) || !md->dso) && !all)
            continue;
        /* Since we're working in reverse this is OK */
        (void)sk_CONF_MODULE_delete(supported_modules, i);
        module_free(md);
        }
    if (sk_CONF_MODULE_num(supported_modules) == 0)
        {
        sk_CONF_MODULE_free(supported_modules);
        supported_modules = NULL;
        }
    }

/* unload a single module */
static void module_free(CONF_MODULE *md)
    {
    if (md->dso)
        DSO_free(md->dso);
    OPENSSL_free(md->name);
    OPENSSL_free(md);
    }

/* finish and free up all modules instances */

void CONF_modules_finish(void)
    {
    CONF_IMODULE *imod;
    while (sk_CONF_IMODULE_num(initialized_modules) > 0)
        {
        imod = sk_CONF_IMODULE_pop(initialized_modules);
        module_finish(imod);
        }
    sk_CONF_IMODULE_free(initialized_modules);
    initialized_modules = NULL;
    }

/* finish a module instance */

static void module_finish(CONF_IMODULE *imod)
    {
    if (imod->pmod->finish)
        imod->pmod->finish(imod);
    imod->pmod->links--;
    OPENSSL_free(imod->name);
    OPENSSL_free(imod->value);
    OPENSSL_free(imod);
    }

/* Add a static module to OpenSSL */

int CONF_module_add(const char *name, conf_init_func *ifunc, 
            conf_finish_func *ffunc)
    {
    if (module_add(NULL, name, ifunc, ffunc))
        return 1;
    else
        return 0;
    }

void CONF_modules_free(void)
    {
    CONF_modules_finish();
    CONF_modules_unload(1);
    }

/* Utility functions */

const char *CONF_imodule_get_name(const CONF_IMODULE *md)
    {
    return md->name;
    }

const char *CONF_imodule_get_value(const CONF_IMODULE *md)
    {
    return md->value;
    }

void *CONF_imodule_get_usr_data(const CONF_IMODULE *md)
    {
    return md->usr_data;
    }

void CONF_imodule_set_usr_data(CONF_IMODULE *md, void *usr_data)
    {
    md->usr_data = usr_data;
    }

CONF_MODULE *CONF_imodule_get_module(const CONF_IMODULE *md)
    {
    return md->pmod;
    }

unsigned long CONF_imodule_get_flags(const CONF_IMODULE *md)
    {
    return md->flags;
    }

void CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
    {
    md->flags = flags;
    }

void *CONF_module_get_usr_data(CONF_MODULE *pmod)
    {
    return pmod->usr_data;
    }

void CONF_module_set_usr_data(CONF_MODULE *pmod, void *usr_data)
    {
    pmod->usr_data = usr_data;
    }

/* Return default config file name */

char *CONF_get1_default_config_file(void)
    {
    char *file;
    int len;

    file = getenv("OPENSSL_CONF");
    if (file) 
        return BUF_strdup(file);

    len = strlen(X509_get_default_cert_area());
#ifndef OPENSSL_SYS_VMS
    len++;
#endif
    len += strlen(OPENSSL_CONF);

    file = OPENSSL_malloc(len + 1);

    if (!file)
        return NULL;
    BUF_strlcpy(file,X509_get_default_cert_area(),len + 1);
#ifndef OPENSSL_SYS_VMS
    BUF_strlcat(file,"/",len + 1);
#endif
    BUF_strlcat(file,OPENSSL_CONF,len + 1);

    return file;
    }

/* This function takes a list separated by 'sep' and calls the
 * callback function giving the start and length of each member
 * optionally stripping leading and trailing whitespace. This can
 * be used to parse comma separated lists for example.
 */

int CONF_parse_list(const char *list_, int sep, int nospc,
    int (*list_cb)(const char *elem, int len, void *usr), void *arg)
    {
    int ret;
    const char *lstart, *tmpend, *p;

    if(list_ == NULL)
        {
        CONFerr(CONF_F_CONF_PARSE_LIST, CONF_R_LIST_CANNOT_BE_NULL);
        return 0;
        }

    lstart = list_;
    for(;;)
        {
        if (nospc)
            {
            while(*lstart && isspace((unsigned char)*lstart))
                lstart++;
            }
        p = strchr(lstart, sep);
        if (p == lstart || !*lstart)
            ret = list_cb(NULL, 0, arg);
        else
            {
            if (p)
                tmpend = p - 1;
            else 
                tmpend = lstart + strlen(lstart) - 1;
            if (nospc)
                {
                while(isspace((unsigned char)*tmpend))
                    tmpend--;
                }
            ret = list_cb(lstart, tmpend - lstart + 1, arg);
            }
        if (ret <= 0)
            return ret;
        if (p == NULL)
            return 1;
        lstart = p + 1;
        }
    }