lib/libgss/g_initialize.c

	g_initialize.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * This file contains functions to initialize the gssapi library and
 * load mechanism libraries.
 *
 * It also contain functions requiring direct access to the mechanism's
 * list (gss_inidicate_mechs and gss_release_oid) as well as support
 * functions which translate the mechanism strings to oids and vise versa.
 *
 * The mechanism libraries are loaded on demand.  This is triggered
 * through the get_mechanism function call.
 *
 * Updates to the mechList are performed with the following restrictions:
 *  - once a library is loaded, none of the fields are updated
 *  - existing entiries for non-loaded mechs, will have the
 *      library and kernel module names updated only
 *      (i.e. the mech oid and mech name will not be updated)
 */

#include <mechglueP.h>
#include <stdio.h>
#include <syslog.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <ctype.h>
#include <errno.h>
#include <synch.h>
#include <dlfcn.h>
#include <libintl.h>


#ifndef TEXT_DOMAIN
#error TEXT_DOMAIN not defined
#endif

#define MECH_CONF "/etc/gss/mech"

#define MECH_LIB_PREFIX1    "/usr/lib/"

/*
 * This #ifdef mess figures out if we are to be compiled into
 * a sparcv9/lp64 binary for the purposes of figuring the absolute location
 * of gss-api mechanism modules.
 */
#ifdef  _LP64

#ifdef  __sparc

#define MECH_LIB_PREFIX2    "sparcv9/"

#elif defined(__amd64)

#define MECH_LIB_PREFIX2    "amd64/"

#else   /* __sparc */

you need to define where under /usr the LP64 libraries live for this platform

#endif  /* __sparc */

#else   /* _LP64 */

#define MECH_LIB_PREFIX2    ""

#endif  /* _LP64 */

#define MECH_LIB_DIR        "gss/"

#define MECH_LIB_PREFIX MECH_LIB_PREFIX1 MECH_LIB_PREFIX2 MECH_LIB_DIR


#ifndef MECH_SYM
#define MECH_SYM "gss_mech_initialize"
#endif

#define M_DEFAULT   "default"

/* Local functions */
static gss_mech_info searchMechList(const gss_OID);
static void loadConfigFile(const char *);
static void updateMechList(void);


/*
 * list of mechanism libraries and their entry points.
 * the list also maintains state of the mech libraries (loaded or not).
 */
static gss_mech_info g_mechList = NULL;
static gss_mech_info g_mechListTail = NULL;
static mutex_t g_mechListLock;
static time_t g_confFileModTime = (time_t)0;

/*
 * function used to reclaim the memory used by a gss_OID structure.
 * This routine requires direct access to the mechList.
 */
OM_uint32
gss_release_oid(minor_status, oid)
OM_uint32 *minor_status;
gss_OID *oid;
{
    OM_uint32 major;
    gss_mech_info aMech = g_mechList;

    if (minor_status == NULL)
        return (GSS_S_CALL_INACCESSIBLE_WRITE);

    *minor_status = 0;

    while (aMech != NULL) {

        /*
         * look through the loaded mechanism libraries for
         * gss_internal_release_oid until one returns success.
         * gss_internal_release_oid will only return success when
         * the OID was recognized as an internal mechanism OID. if no
         * mechanisms recognize the OID, then call the generic version.
         */

        /*
         * we can walk the mechanism list without a mutex, because we
         * are only looking at fields which once read will never change.
         * Mechanism entries are always added to the end, and as
         * complete entries.
         */
        if (aMech->mech && aMech->mech->gss_internal_release_oid) {
            major = aMech->mech->gss_internal_release_oid(
                    aMech->mech->context,
                    minor_status, oid);
            if (major == GSS_S_COMPLETE)
                return (GSS_S_COMPLETE);
        }
        aMech = aMech->next;
    } /* while */

    return (generic_gss_release_oid(minor_status, oid));
} /* gss_release_oid */


/*
 * this function will return an oid set indicating available mechanisms.
 * The set returned is based on configuration file entries and
 * NOT on the loaded mechanisms.  This function does not check if any
 * of these can actually be loaded.
 * This routine needs direct access to the mechanism list.
 * To avoid reading the configuration file each call, we will save a
 * a mech oid set, and only update it once the file has changed.
 */
static time_t g_mechSetTime = (time_t)0;
static gss_OID_set_desc g_mechSet = { 0, NULL };
static mutex_t g_mechSetLock;


OM_uint32
gss_indicate_mechs(minorStatus, mechSet)
OM_uint32 *minorStatus;
gss_OID_set *mechSet;
{
    gss_mech_info mList;
    char *fileName;
    struct stat fileInfo;
    int count, i, j;
    gss_OID curItem;

    if (!minorStatus)
        return (GSS_S_CALL_INACCESSIBLE_WRITE);

    *minorStatus = 0;


    /* check output parameter */
    if (mechSet == NULL)
        return (GSS_S_CALL_INACCESSIBLE_WRITE);

    fileName = MECH_CONF;

    /*
     * If we have already computed the mechanisms supported and if it
     * is still valid; make a copy and return to caller,
     * otherwise build it first.
     */
    if ((stat(fileName, &fileInfo) == 0 &&
        fileInfo.st_mtime > g_mechSetTime)) {
        /*
         * lock the mutex since we will be updating
         * the mechList structure
         * we need to keep the lock while we build the mechanism list
         * since we are accessing parts of the mechList which could be
         * modified.
         */
        (void) mutex_lock(&g_mechListLock);

        /*
         * this checks for the case when we need to re-construct the
         * g_mechSet structure, but the mechanism list is upto date
         * (because it has been read by someone calling
         * __gss_get_mechanism)
         */
        if (fileInfo.st_mtime > g_confFileModTime)
        {
            g_confFileModTime = fileInfo.st_mtime;
            loadConfigFile(fileName);
        }

        /*
         * we need to lock the mech set so that no one else will
         * try to read it as we are re-creating it
         */
        (void) mutex_lock(&g_mechSetLock);

        /* if the oid list already exists we must free it first */
        if (g_mechSet.count != 0) {
            for (i = 0; i < g_mechSet.count; i++)
                free(g_mechSet.elements[i].elements);
            free(g_mechSet.elements);
            g_mechSet.elements = NULL;
            g_mechSet.count = 0;
        }

        /* determine how many elements to have in the list */
        mList = g_mechList;
        count = 0;
        while (mList != NULL) {
            count++;
            mList = mList->next;
        }

        /* this should always be true, but.... */
        if (count > 0) {
            g_mechSet.elements =
                (gss_OID) calloc(count, sizeof (gss_OID_desc));
            if (g_mechSet.elements == NULL) {
                (void) mutex_unlock(&g_mechSetLock);
                (void) mutex_unlock(&g_mechListLock);
                return (GSS_S_FAILURE);
            }

            (void) memset(g_mechSet.elements, 0,
                count * sizeof (gss_OID_desc));

            /* now copy each oid element */
            g_mechSet.count = count;
            count = 0;
            mList = g_mechList;
            while (mList != NULL) {
                curItem = &(g_mechSet.elements[count]);
                curItem->elements = (void*)
                    malloc(mList->mech_type->length);
                if (curItem->elements == NULL) {
                    /*
                     * this is nasty - we must delete the
                     * part of the array already copied
                     */
                    for (i = 0; i < count; i++) {
                        free(g_mechSet.elements[i].
                            elements);
                    }
                    free(g_mechSet.elements);
                    g_mechSet.count = 0;
                    g_mechSet.elements = NULL;
                    (void) mutex_unlock(&g_mechSetLock);
                    (void) mutex_unlock(&g_mechListLock);
                    return (GSS_S_FAILURE);
                }
                g_OID_copy(curItem, mList->mech_type);
                count++;
                mList = mList->next;
            }
        }

        g_mechSetTime = fileInfo.st_mtime;
        (void) mutex_unlock(&g_mechSetLock);
        (void) mutex_unlock(&g_mechListLock);
    } /* if g_mechSet is out of date or not initialized */

    /*
     * the mech set is created and it is up to date
     * so just copy it to caller
     */
    if ((*mechSet =
        (gss_OID_set) malloc(sizeof (gss_OID_set_desc))) == NULL)
    {
        return (GSS_S_FAILURE);
    }

    /*
     * need to lock the g_mechSet in case someone tries to update it while
     * I'm copying it.
     */
    (void) mutex_lock(&g_mechSetLock);

    /* allocate space for the oid structures */
    if (((*mechSet)->elements =
        (void*) calloc(g_mechSet.count, sizeof (gss_OID_desc)))
        == NULL)
    {
        (void) mutex_unlock(&g_mechSetLock);
        free(*mechSet);
        *mechSet = NULL;
        return (GSS_S_FAILURE);
    }

    /* now copy the oid structures */
    (void) memcpy((*mechSet)->elements, g_mechSet.elements,
        g_mechSet.count * sizeof (gss_OID_desc));

    (*mechSet)->count = g_mechSet.count;

    /* still need to copy each of the oid elements arrays */
    for (i = 0; i < (*mechSet)->count; i++) {
        curItem = &((*mechSet)->elements[i]);
        curItem->elements =
            (void *) malloc(g_mechSet.elements[i].length);
        if (curItem->elements == NULL) {
            (void) mutex_unlock(&g_mechSetLock);
            /*
             * must still free the allocated elements for
             * each allocated gss_OID_desc
             */
            for (j = 0; j < i; j++) {
                free((*mechSet)->elements[j].elements);
            }
            free((*mechSet)->elements);
            free(mechSet);
            *mechSet = NULL;
            return (GSS_S_FAILURE);
        }
        g_OID_copy(curItem, &g_mechSet.elements[i]);
    }
    (void) mutex_unlock(&g_mechSetLock);
    return (GSS_S_COMPLETE);
} /* gss_indicate_mechs */

/*
 * this function has been added for use by modules that need to
 * know what (if any) optional parameters are supplied in the
 * config file (MECH_CONF).
 * It will return the option string for a specified mechanism.
 * caller is responsible for freeing the memory
 */
char *
__gss_get_modOptions(oid)
const gss_OID oid;
{
    gss_mech_info aMech;
    char *modOptions = NULL;

    /* make sure we have fresh data */
    (void) mutex_lock(&g_mechListLock);
    updateMechList();
    (void) mutex_unlock(&g_mechListLock);

    /* searching the list does not require a lock */
    if ((aMech = searchMechList(oid)) == NULL ||
        aMech->optionStr == NULL) {
        return (NULL);
    }

    /*
     * need to obtain a lock on this structure in case someone else
     * will try to update it during the copy
     */
    (void) mutex_lock(&g_mechListLock);
    if (aMech->optionStr)
        modOptions = strdup(aMech->optionStr);
    (void) mutex_unlock(&g_mechListLock);

    return (modOptions);
} /* __gss_get_modOptions */

/*
 * this function has been added for use by gssd.
 * It will return the kernel module name for a specified mechanism.
 * caller is responsible for freeing the memory
 */
char *
__gss_get_kmodName(oid)
const gss_OID oid;
{
    gss_mech_info aMech;
    char *kmodName = NULL;

    /* make sure we have fresh data */
    (void) mutex_lock(&g_mechListLock);
    updateMechList();
    (void) mutex_unlock(&g_mechListLock);

    /* searching the list does not require a lock */
    if ((aMech = searchMechList(oid)) == NULL || aMech->kmodName == NULL) {
        return (NULL);
    }

    /*
     * need to obtain a lock on this structure in case someone else
     * will try to update it during the copy
     */
    (void) mutex_lock(&g_mechListLock);
    if (aMech->kmodName)
        kmodName = strdup(aMech->kmodName);
    (void) mutex_unlock(&g_mechListLock);

    return (kmodName);
} /* __gss_get_kmodName */


/*
 * given a mechanism string return the mechanism oid
 */
OM_uint32
__gss_mech_to_oid(const char *mechStr, gss_OID* oid)
{
    gss_mech_info aMech;

    if (oid == NULL)
        return (GSS_S_CALL_INACCESSIBLE_WRITE);

    *oid = GSS_C_NULL_OID;

    if ((mechStr == NULL) || (strlen(mechStr) == 0) ||
        (strcasecmp(mechStr, M_DEFAULT) == 0))
        return (GSS_S_COMPLETE);

    /* ensure we have fresh data */
    (void) mutex_lock(&g_mechListLock);
    updateMechList();
    (void) mutex_unlock(&g_mechListLock);

    aMech = g_mechList;

    /* no lock required - only looking at fields that are not updated */
    while (aMech != NULL) {
        if ((aMech->mechNameStr) &&
            strcmp(aMech->mechNameStr, mechStr) == 0) {
            *oid = aMech->mech_type;
            return (GSS_S_COMPLETE);
        }
        aMech = aMech->next;
    }
    return (GSS_S_FAILURE);
} /* __gss_mech_to_oid */


/*
 * Given the mechanism oid, return the readable mechanism name
 * associated with that oid from the mech config file
 * (/etc/gss/mech).
 */
const char *
__gss_oid_to_mech(const gss_OID oid)
{
    gss_mech_info aMech;

    if (oid == GSS_C_NULL_OID)
        return (M_DEFAULT);

    /* ensure we have fresh data */
    (void) mutex_lock(&g_mechListLock);
    updateMechList();
    (void) mutex_unlock(&g_mechListLock);

    if ((aMech = searchMechList(oid)) == NULL)
        return (NULL);

    return (aMech->mechNameStr);
} /* __gss_oid_to_mech */


/*
 * return a list of mechanism strings supported
 * upon return the array is terminated with a NULL entry
 */
OM_uint32
__gss_get_mechanisms(char *mechArray[], int arrayLen)
{
    gss_mech_info aMech;
    int i;

    if (mechArray == NULL || arrayLen < 1)
        return (GSS_S_CALL_INACCESSIBLE_WRITE);

    /* ensure we have fresh data */
    (void) mutex_lock(&g_mechListLock);
    updateMechList();
    (void) mutex_unlock(&g_mechListLock);

    aMech = g_mechList;

    /* no lock required - only looking at fields that are not updated */
    for (i = 1; i < arrayLen; i++) {
        if (aMech != NULL) {
            *mechArray = aMech->mechNameStr;
            mechArray++;
            aMech = aMech->next;
        } else
            break;
    }
    *mechArray = NULL;
    return (GSS_S_COMPLETE);
} /* gss_get_mechanisms */


/*
 * determines if the mechList needs to be updated from file
 * and performs the update.
 * this functions must be called with a lock of g_mechListLock
 */
static void
updateMechList(void)
{
    char *fileName;
    struct stat fileInfo;

    fileName = MECH_CONF;

    /* check if mechList needs updating */
    if (stat(fileName, &fileInfo) == 0 &&
        (fileInfo.st_mtime > g_confFileModTime)) {
        loadConfigFile(fileName);
        g_confFileModTime = fileInfo.st_mtime;
    }
} /* updateMechList */


/*
 * given the mechanism type, return the mechanism structure
 * containing the mechanism library entry points.
 * will return NULL if mech type is not found
 * This function will also trigger the loading of the mechanism
 * module if it has not been already loaded.
 */
gss_mechanism
__gss_get_mechanism(oid)
const gss_OID oid;
{
    gss_mech_info aMech;
    gss_mechanism (*sym)(const gss_OID);
    void *dl;

    /* check if the mechanism is already loaded */
    if ((aMech = searchMechList(oid)) != NULL && aMech->mech) {
        return (aMech->mech);
    }

    /*
     * might need to re-read the configuration file before loading
     * the mechanism to ensure we have the latest info.
     */
    (void) mutex_lock(&g_mechListLock);
    updateMechList();

    aMech = searchMechList(oid);

    /* is the mechanism present in the list ? */
    if (aMech == NULL) {
        (void) mutex_unlock(&g_mechListLock);
        return ((gss_mechanism)NULL);
    }

    /* has another thread loaded the mech */
    if (aMech->mech) {
        (void) mutex_unlock(&g_mechListLock);
        return (aMech->mech);
    }

    /* we found the mechanism, but it is not loaded */
    if ((dl = dlopen(aMech->uLibName, RTLD_NOW)) == NULL) {
        (void) syslog(LOG_INFO, "libgss dlopen(%s): %s\n",
                aMech->uLibName, dlerror());
        (void) mutex_unlock(&g_mechListLock);
        return ((gss_mechanism)NULL);
    }

    if ((sym = (gss_mechanism (*)(const gss_OID))dlsym(dl, MECH_SYM))
            == NULL) {
        (void) dlclose(dl);
        (void) syslog(LOG_INFO, "unable to initialize mechanism"
                " library [%s]\n", aMech->uLibName);
        (void) mutex_unlock(&g_mechListLock);
        return ((gss_mechanism)NULL);
    }

    /* Call the symbol to get the mechanism table */
    aMech->mech = (*sym)(aMech->mech_type);

    if (aMech->mech == NULL) {
        (void) dlclose(dl);
        (void) syslog(LOG_INFO, "unable to initialize mechanism"
                " library [%s]\n", aMech->uLibName);
        (void) mutex_unlock(&g_mechListLock);
        return ((gss_mechanism)NULL);
    }

    aMech->dl_handle = dl;

    (void) mutex_unlock(&g_mechListLock);
    return (aMech->mech);
} /* __gss_get_mechanism */

gss_mechanism_ext
__gss_get_mechanism_ext(oid)
const gss_OID oid;
{
    gss_mech_info aMech;
    gss_mechanism_ext mech_ext;

    /* check if the mechanism is already loaded */
    if ((aMech = searchMechList(oid)) != NULL && aMech->mech_ext != NULL)
        return (aMech->mech_ext);

    if (__gss_get_mechanism(oid) == NULL)
        return (NULL);

    if (aMech->dl_handle == NULL)
        return (NULL);

    /* Load the gss_config_ext struct for this mech */

    mech_ext = (gss_mechanism_ext)malloc(sizeof (struct gss_config_ext));

    if (mech_ext == NULL)
        return (NULL);

    /*
     * dlsym() the mech's 'method' functions for the extended APIs
     *
     * NOTE:  Until the void *context argument is removed from the
     * SPI method functions' signatures it will be necessary to have
     * different function pointer typedefs and function names for
     * the SPI methods than for the API.  When this argument is
     * removed it will be possible to rename gss_*_sfct to gss_*_fct
     * and and gssspi_* to gss_*.
     */
    mech_ext->gss_acquire_cred_with_password =
        (gss_acquire_cred_with_password_sfct)dlsym(aMech->dl_handle,
            "gssspi_acquire_cred_with_password");

    /* Set aMech->mech_ext */
    (void) mutex_lock(&g_mechListLock);

    if (aMech->mech_ext == NULL)
        aMech->mech_ext = mech_ext;
    else
        free(mech_ext); /* we raced and lost; don't leak */

    (void) mutex_unlock(&g_mechListLock);

    return (aMech->mech_ext);

} /* __gss_get_mechanism_ext */


/*
 * this routine is used for searching the list of mechanism data.
 * it needs not be mutex protected because we only add new structures
 * from the end and they are fully initialized before being added.
 */
static gss_mech_info searchMechList(oid)
const gss_OID oid;
{
    gss_mech_info aMech = g_mechList;

    /* if oid is null -> then get default which is the first in the list */
    if (oid == GSS_C_NULL_OID)
        return (aMech);

    while (aMech != NULL) {
        if (g_OID_equal(aMech->mech_type, oid))
            return (aMech);
        aMech = aMech->next;
    }

    /* none found */
    return ((gss_mech_info) NULL);
} /* searchMechList */


/*
 * loads the configuration file
 * this is called while having a mutex lock on the mechanism list
 * entries for libraries that have been loaded can't be modified
 * mechNameStr and mech_type fields are not updated during updates
 */
static void loadConfigFile(fileName)
const char *fileName;
{
    char buffer[BUFSIZ], *oidStr, *oid, *sharedLib, *kernMod, *endp;
    char *modOptions;
    char sharedPath[sizeof (MECH_LIB_PREFIX) + BUFSIZ];
    char *tmpStr;
    FILE *confFile;
    gss_OID mechOid;
    gss_mech_info aMech, tmp;
    OM_uint32 minor;
    gss_buffer_desc oidBuf;

    if ((confFile = fopen(fileName, "r")) == NULL) {
        return;
    }

    (void) memset(buffer, 0, sizeof (buffer));
    while (fgets(buffer, BUFSIZ, confFile) != NULL) {

        /* ignore lines beginning with # */
        if (*buffer == '#')
            continue;

        /*
         * find the first white-space character after
         * the mechanism name
         */
        oidStr = buffer;
        for (oid = buffer; *oid && !isspace(*oid); oid++);

        /* Now find the first non-white-space character */
        if (*oid) {
            *oid = '\0';
            oid++;
            while (*oid && isspace(*oid))
                oid++;
        }

        /*
         * If that's all, then this is a corrupt entry. Skip it.
         */
        if (! *oid)
            continue;

        /* Find the end of the oid and make sure it is NULL-ended */
        for (endp = oid; *endp && !isspace(*endp); endp++)
            ;

        if (*endp) {
            *endp = '\0';
        }

        /*
         * check if an entry for this oid already exists
         * if it does, and the library is already loaded then
         * we can't modify it, so skip it
         */
        oidBuf.value = (void *)oid;
        oidBuf.length = strlen(oid);
        if (generic_gss_str_to_oid(&minor, &oidBuf, &mechOid)
            != GSS_S_COMPLETE) {
            (void) syslog(LOG_INFO, "invalid mechanism oid"
                    " [%s] in configuration file", oid);
            continue;
        }

        aMech = searchMechList(mechOid);
        if (aMech && aMech->mech) {
            free(mechOid->elements);
            free(mechOid);
            continue;
        }

        /* Find the start of the shared lib name */
        for (sharedLib = endp+1; *sharedLib && isspace(*sharedLib);
            sharedLib++)
            ;

        /*
         * If that's all, then this is a corrupt entry. Skip it.
         */
        if (! *sharedLib) {
            free(mechOid->elements);
            free(mechOid);
            continue;
        }

        /*
         * Find the end of the shared lib name and make sure it is
         *  NULL-terminated.
         */
        for (endp = sharedLib; *endp && !isspace(*endp); endp++)
            ;

        if (*endp) {
            *endp = '\0';
        }

        /* Find the start of the optional kernel module lib name */
        for (kernMod = endp+1; *kernMod && isspace(*kernMod);
            kernMod++)
            ;

        /*
         * If this item starts with a bracket "[", then
         * it is not a kernel module, but is a list of
         * options for the user module to parse later.
         */
        if (*kernMod && *kernMod != '[') {
            /*
             * Find the end of the shared lib name and make sure
             * it is NULL-terminated.
             */
            for (endp = kernMod; *endp && !isspace(*endp); endp++)
                ;

            if (*endp) {
                *endp = '\0';
            }
        } else
            kernMod = NULL;

        /* Find the start of the optional module options list */
        for (modOptions = endp+1; *modOptions && isspace(*modOptions);
            modOptions++);

        if (*modOptions == '[')  {
            /* move past the opening bracket */
            for (modOptions = modOptions+1;
                *modOptions && isspace(*modOptions);
                modOptions++);

            /* Find the closing bracket */
            for (endp = modOptions;
                *endp && *endp != ']'; endp++);

            if (endp)
                *endp = '\0';

        } else {
            modOptions = NULL;
        }

        (void) strcpy(sharedPath, MECH_LIB_PREFIX);
        (void) strcat(sharedPath, sharedLib);

        /*
         * are we creating a new mechanism entry or
         * just modifying existing (non loaded) mechanism entry
         */
        if (aMech) {
            /*
             * delete any old values and set new
             * mechNameStr and mech_type are not modified
             */
            if (aMech->kmodName) {
                free(aMech->kmodName);
                aMech->kmodName = NULL;
            }

            if (aMech->optionStr) {
                free(aMech->optionStr);
                aMech->optionStr = NULL;
            }

            if ((tmpStr = strdup(sharedPath)) != NULL) {
                if (aMech->uLibName)
                    free(aMech->uLibName);
                aMech->uLibName = tmpStr;
            }

            if (kernMod) /* this is an optional parameter */
                aMech->kmodName = strdup(kernMod);

            if (modOptions) /* optional module options */
                aMech->optionStr = strdup(modOptions);

            /* the oid is already set */
            free(mechOid->elements);
            free(mechOid);
            continue;
        }

        /* adding a new entry */
        aMech = malloc(sizeof (struct gss_mech_config));
        if (aMech == NULL) {
            free(mechOid->elements);
            free(mechOid);
            continue;
        }
        (void) memset(aMech, 0, sizeof (struct gss_mech_config));
        aMech->mech_type = mechOid;
        aMech->uLibName = strdup(sharedPath);
        aMech->mechNameStr = strdup(oidStr);

        /* check if any memory allocations failed - bad news */
        if (aMech->uLibName == NULL || aMech->mechNameStr == NULL) {
            if (aMech->uLibName)
                free(aMech->uLibName);
            if (aMech->mechNameStr)
                free(aMech->mechNameStr);
            free(mechOid->elements);
            free(mechOid);
            free(aMech);
            continue;
        }
        if (kernMod)    /* this is an optional parameter */
            aMech->kmodName = strdup(kernMod);

        if (modOptions)
            aMech->optionStr = strdup(modOptions);
        /*
         * add the new entry to the end of the list - make sure
         * that only complete entries are added because other
         * threads might currently be searching the list.
         */
        tmp = g_mechListTail;
        g_mechListTail = aMech;

        if (tmp != NULL)
            tmp->next = aMech;

        if (g_mechList == NULL)
            g_mechList = aMech;
    } /* while */
    (void) fclose(confFile);
} /* loadConfigFile */