import less(1)

[unleashed/tickless.git] / usr / src / lib / libc / port / gen / crypt.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma weak _crypt = crypt
#pragma weak _encrypt = encrypt
#pragma weak _setkey = setkey

#include "lint.h"
#include "mtlib.h"
#include <synch.h>
#include <thread.h>
#include <ctype.h>
#include <dlfcn.h>
#include <errno.h>
#include <stdio.h>
#include <strings.h>
#include <stdlib.h>
#include <sys/time.h>
#include <limits.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <syslog.h>
#include <unistd.h>
#include <atomic.h>

#include <crypt.h>
#include <libc.h>
#include "tsd.h"

#define CRYPT_ALGORITHMS_ALLOW          "CRYPT_ALGORITHMS_ALLOW"
#define CRYPT_ALGORITHMS_DEPRECATE      "CRYPT_ALGORITHMS_DEPRECATE"
#define CRYPT_DEFAULT                   "CRYPT_DEFAULT"
#define CRYPT_UNIX                      "__unix__"

#define CRYPT_CONFFILE          "/etc/security/crypt.conf"
#define POLICY_CONF_FILE        "/etc/security/policy.conf"

#define CRYPT_CONFLINELENGTH    1024

#define CRYPT_MODULE_ISA        "/$ISA/"
#ifdef  _LP64
#define CRYPT_MODULE_DIR        "/usr/lib/security/64/"
#define CRYPT_ISA_DIR           "/64/"
#else   /* !_LP64 */
#define CRYPT_MODULE_DIR        "/usr/lib/security/"
#define CRYPT_ISA_DIR           "/"
#endif  /* _LP64 */

/*
 * MAX_ALGNAME_LEN:
 *
 * In practical terms this is probably never any bigger than about 10, but...
 *
 * It has to fix the encrypted password filed of struct spwd it is
 * theoretically the maximum length of the cipher minus the magic $ sign.
 * Though that would be unexpected.
 * Since it also has to fit in crypt.conf it is CRYPT_CONFLINELENGTH
 * minus the path to the module and the minimum white space.
 *
 * CRYPT_MAXCIPHERTEXTLEN is defined in crypt.h and is smaller than
 * CRYPT_CONFLINELENGTH, and probably always will be.
 */
#define MAX_ALGNAME_LEN (CRYPT_MAXCIPHERTEXTLEN - 1)

struct crypt_alg_s {
        void    *a_libhandle;
        char    *(*a_genhash)(char *, const size_t, const char *,
                    const char *, const char **);
        char    *(*a_gensalt)(char *, const size_t,
                    const char *, const struct passwd *, const char **);
        char    **a_params;
        int     a_nparams;
};

struct crypt_policy_s {
        char    *cp_default;
        char    *cp_allow;
        char    *cp_deny;
};

enum crypt_policy_error_e {
        CPE_BOTH = 1,
        CPE_MULTI
};

static struct crypt_policy_s *getcryptpolicy(void);
static void free_crypt_policy(struct crypt_policy_s *policy);
static struct crypt_alg_s  *getalgbyname(const char *algname, boolean_t *found);
static void free_crypt_alg(struct crypt_alg_s *alg);
static char *getalgfromsalt(const char *salt);
static boolean_t alg_valid(const char *algname,
    const struct crypt_policy_s *policy);
static char *isa_path(const char *path);

static char *_unix_crypt(const char *pw, const char *salt, char *iobuf);
static char *_unix_crypt_gensalt(char *gsbuffer, size_t gsbufflen,
            const char *oldpuresalt, const struct passwd *userinfo,
            const char *params[]);


/*
 * crypt - string encoding function
 *
 * This function encodes strings in a suitable for for secure storage
 * as passwords.  It generates the password hash given the plaintext and salt.
 *
 * If the first character of salt is "$" then we use crypt.conf(4) to
 * determine which plugin to use and run the crypt_genhash_impl(3c) function
 * from it.
 * Otherwise we use the old unix algorithm.
 *
 * RETURN VALUES
 *      On Success we return a pointer to the encoded string.  The
 *      return value points to thread specific static data and should NOT
 *      be passed free(3c).
 *      On failure we return NULL and set errno to one of:
 *              EINVAL, ELIBACC, ENOMEM, ENOSYS.
 */
char *
crypt(const char *plaintext, const char *salt)
{
        struct crypt_alg_s *alg;
        char *ctbuffer;
        char *ciphertext;
        char *algname;
        boolean_t found;

        ctbuffer = tsdalloc(_T_CRYPT, CRYPT_MAXCIPHERTEXTLEN, NULL);
        if (ctbuffer == NULL)
                return (NULL);
        bzero(ctbuffer, CRYPT_MAXCIPHERTEXTLEN);

        /*
         * '$' is never a possible salt char with the traditional unix
         * algorithm.  If the salt passed in is NULL or the first char
         * of the salt isn't a $ then do the traditional thing.
         * We also do the traditional thing if the salt is only 1 char.
         */
        if (salt == NULL || salt[0] != '$' || strlen(salt) == 1) {
                return (_unix_crypt(plaintext, salt, ctbuffer));
        }

        /*
         * Find the algorithm name from the salt and look it up in
         * crypt.conf(4) to find out what shared object to use.
         * If we can't find it in crypt.conf then getalgbyname would
         * have returned with found = B_FALSE so we use the unix algorithm.
         * If alg is NULL but found = B_TRUE then there is a problem with
         * the plugin so we fail leaving errno set to what getalgbyname()
         * set it to or EINVAL it if wasn't set.
         */
        if ((algname = getalgfromsalt(salt)) == NULL) {
                return (NULL);
        }

        errno = 0;
        alg = getalgbyname(algname, &found);
        if ((alg == NULL) || !found) {
                if (errno == 0)
                        errno = EINVAL;
                ciphertext = NULL;
                goto cleanup;
        } else if (!found) {
                ciphertext = _unix_crypt(plaintext, salt, ctbuffer);
        } else {
                ciphertext = alg->a_genhash(ctbuffer, CRYPT_MAXCIPHERTEXTLEN,
                    plaintext, salt, (const char **)alg->a_params);
        }

cleanup:
        free_crypt_alg(alg);
        free(algname);

        return (ciphertext);
}

/*
 * crypt_gensalt - generate salt string for string encoding
 *
 * This function generates the salt string pased to crypt(3c).
 * If oldsalt is NULL, the use the default algorithm.
 * Other wise check the policy in policy.conf to ensure that it is
 * either still allowed or not deprecated.
 *
 * RETURN VALUES
 *      Return a pointer to the new salt, the caller is responsible
 *      for using free(3c) on the return value.
 *      Returns NULL on error and sets errno to one of:
 *              EINVAL, ELIBACC, ENOMEM
 */
char *
crypt_gensalt(const char *oldsalt, const struct passwd *userinfo)
{
        struct crypt_alg_s *alg = NULL;
        struct crypt_policy_s *policy = NULL;
        char *newsalt = NULL;
        char *gsbuffer;
        char *algname = NULL;
        boolean_t found;

        gsbuffer = calloc(CRYPT_MAXCIPHERTEXTLEN, sizeof (char *));
        if (gsbuffer == NULL) {
                errno = ENOMEM;
                goto cleanup;
        }

        policy = getcryptpolicy();
        if (policy == NULL) {
                errno = EINVAL;
                goto cleanup;
        }

        algname = getalgfromsalt(oldsalt);
        if (!alg_valid(algname, policy)) {
                free(algname);
                algname = strdup(policy->cp_default);
        }

        if (strcmp(algname, CRYPT_UNIX) == 0) {
                newsalt = _unix_crypt_gensalt(gsbuffer, CRYPT_MAXCIPHERTEXTLEN,
                    oldsalt, userinfo, NULL);
        } else {
                errno = 0;
                alg = getalgbyname(algname, &found);
                if (alg == NULL || !found) {
                        if (errno == 0)
                                errno = EINVAL;
                        goto cleanup;
                }
                newsalt = alg->a_gensalt(gsbuffer, CRYPT_MAXCIPHERTEXTLEN,
                    oldsalt, userinfo, (const char **)alg->a_params);
        }

cleanup:
        free_crypt_policy(policy);
        free_crypt_alg(alg);
        if (newsalt == NULL)
                free(gsbuffer);
        free(algname);

        return (newsalt);
}

/*
 * ===========================================================================
 * The remainder of this file contains internal interfaces for
 * the implementation of crypt(3c) and crypt_gensalt(3c)
 * ===========================================================================
 */


/*
 * getalgfromsalt - extract the algorithm name from the salt string
 */
static char *
getalgfromsalt(const char *salt)
{
        char algname[CRYPT_MAXCIPHERTEXTLEN];
        int i;
        int j;

        if (salt == NULL || strlen(salt) > CRYPT_MAXCIPHERTEXTLEN)
                return (NULL);
        /*
         * Salts are in this format:
         * $<algname>[,var=val,[var=val ...][$puresalt]$<ciphertext>
         *
         * The only bit we need to worry about here is extracting the
         * name which is the string between the first "$" and the first
         * of "," or second "$".
         */
        if (salt[0] != '$') {
                return (strdup(CRYPT_UNIX));
        }

        i = 1;
        j = 0;
        while (salt[i] != '\0' && salt[i] != '$' && salt[i] != ',') {
                algname[j] = salt[i];
                i++;
                j++;
        }
        if (j == 0)
                return (NULL);

        algname[j] = '\0';

        return (strdup(algname));
}


/*
 * log_invalid_policy - syslog helper
 */
static void
log_invalid_policy(enum crypt_policy_error_e error, char *value)
{
        switch (error) {
        case CPE_BOTH:
                syslog(LOG_AUTH | LOG_ERR,
                    "crypt(3c): %s contains both %s and %s; only one may be "
                    "specified, using first entry in file.", POLICY_CONF_FILE,
                    CRYPT_ALGORITHMS_ALLOW, CRYPT_ALGORITHMS_DEPRECATE);
                break;
        case CPE_MULTI:
                syslog(LOG_AUTH | LOG_ERR,
                    "crypt(3c): %s contains multiple %s entries;"
                    "using first entry file.", POLICY_CONF_FILE, value);
                break;
        }
}

static char *
getval(const char *ival)
{
        char *tmp;
        char *oval;
        int off;

        if (ival == NULL)
                return (NULL);

        if ((tmp = strchr(ival, '=')) == NULL)
                return (NULL);

        oval = strdup(tmp + 1); /* everything after the "=" */
        if (oval == NULL)
                return (NULL);
        off = strlen(oval) - 1;
        if (off < 0) {
                free(oval);
                return (NULL);
        }
        if (oval[off] == '\n')
                oval[off] = '\0';

        return (oval);
}

/*
 * getcryptpolicy - read /etc/security/policy.conf into a crypt_policy_s
 */
static struct crypt_policy_s *
getcryptpolicy(void)
{
        FILE    *pconf;
        char    line[BUFSIZ];
        struct crypt_policy_s *policy;

        if ((pconf = fopen(POLICY_CONF_FILE, "rF")) == NULL) {
                return (NULL);
        }

        policy = malloc(sizeof (struct crypt_policy_s));
        if (policy == NULL) {
                return (NULL);
        }
        policy->cp_default = NULL;
        policy->cp_allow = NULL;
        policy->cp_deny = NULL;

        while (!feof(pconf) &&
            (fgets(line, sizeof (line), pconf) != NULL)) {
                if (strncasecmp(CRYPT_DEFAULT, line,
                    strlen(CRYPT_DEFAULT)) == 0) {
                        if (policy->cp_default != NULL) {
                                log_invalid_policy(CPE_MULTI, CRYPT_DEFAULT);
                        } else {
                                policy->cp_default = getval(line);
                        }
                }
                if (strncasecmp(CRYPT_ALGORITHMS_ALLOW, line,
                    strlen(CRYPT_ALGORITHMS_ALLOW)) == 0) {
                        if (policy->cp_deny != NULL) {
                                log_invalid_policy(CPE_BOTH, NULL);
                        } else if (policy->cp_allow != NULL) {
                                log_invalid_policy(CPE_MULTI,
                                    CRYPT_ALGORITHMS_ALLOW);
                        } else {
                                policy->cp_allow = getval(line);
                        }
                }
                if (strncasecmp(CRYPT_ALGORITHMS_DEPRECATE, line,
                    strlen(CRYPT_ALGORITHMS_DEPRECATE)) == 0) {
                        if (policy->cp_allow != NULL) {
                                log_invalid_policy(CPE_BOTH, NULL);
                        } else if (policy->cp_deny != NULL) {
                                log_invalid_policy(CPE_MULTI,
                                    CRYPT_ALGORITHMS_DEPRECATE);
                        } else {
                                policy->cp_deny = getval(line);
                        }
                }
        }
        (void) fclose(pconf);

        if (policy->cp_default == NULL) {
                policy->cp_default = strdup(CRYPT_UNIX);
                if (policy->cp_default == NULL)
                        free_crypt_policy(policy);
        }

        return (policy);
}


/*
 * alg_valid - is this algorithm valid given the policy ?
 */
static boolean_t
alg_valid(const char *algname, const struct crypt_policy_s *policy)
{
        char *lasts;
        char *list;
        char *entry;
        boolean_t allowed = B_FALSE;

        if ((algname == NULL) || (policy == NULL)) {
                return (B_FALSE);
        }

        if (strcmp(algname, policy->cp_default) == 0) {
                return (B_TRUE);
        }

        if (policy->cp_deny != NULL) {
                list = policy->cp_deny;
                allowed = B_FALSE;
        } else if (policy->cp_allow != NULL) {
                list = policy->cp_allow;
                allowed = B_TRUE;
        } else {
                /*
                 * Neither of allow or deny policies are set so anything goes.
                 */
                return (B_TRUE);
        }
        lasts = list;
        while ((entry = strtok_r(NULL, ",", &lasts)) != NULL) {
                if (strcmp(entry, algname) == 0) {
                        return (allowed);
                }
        }

        return (!allowed);
}

/*
 * getalgbyname - read crypt.conf(4) looking for algname
 *
 * RETURN VALUES
 *      On error NULL and errno is set
 *      On success the alg details including an open handle to the lib
 *      If crypt.conf(4) is okay but algname doesn't exist in it then
 *      return NULL the caller should then use the default algorithm
 *      as per the policy.
 */
static struct crypt_alg_s *
getalgbyname(const char *algname, boolean_t *found)
{
        struct stat     stb;
        int             configfd;
        FILE            *fconf = NULL;
        struct crypt_alg_s *alg = NULL;
        char            line[CRYPT_CONFLINELENGTH];
        int             linelen = 0;
        int             lineno = 0;
        char            *pathname = NULL;
        char            *lasts = NULL;
        char            *token = NULL;

        *found = B_FALSE;
        if ((algname == NULL) || (strcmp(algname, CRYPT_UNIX) == 0)) {
                return (NULL);
        }

        if ((configfd = open(CRYPT_CONFFILE, O_RDONLY)) == -1) {
                syslog(LOG_ALERT, "crypt: open(%s) failed: %s",
                    CRYPT_CONFFILE, strerror(errno));
                return (NULL);
        }

        /*
         * Stat the file so we can check modes and ownerships
         */
        if (fstat(configfd, &stb) < 0) {
                syslog(LOG_ALERT, "crypt: stat(%s) failed: %s",
                    CRYPT_CONFFILE, strerror(errno));
                goto cleanup;
        }

        /*
         * Check the ownership of the file
         */
        if (stb.st_uid != (uid_t)0) {
                syslog(LOG_ALERT,
                    "crypt: Owner of %s is not root", CRYPT_CONFFILE);
                goto cleanup;
        }

        /*
         * Check the modes on the file
         */
        if (stb.st_mode & S_IWGRP) {
                syslog(LOG_ALERT,
                    "crypt: %s writable by group", CRYPT_CONFFILE);
                goto cleanup;
        }
        if (stb.st_mode & S_IWOTH) {
                syslog(LOG_ALERT,
                    "crypt: %s writable by world", CRYPT_CONFFILE);
                goto cleanup;
        }

        if ((fconf = fdopen(configfd, "rF")) == NULL) {
                syslog(LOG_ALERT, "crypt: fdopen(%d) failed: %s",
                    configfd, strerror(errno));
                goto cleanup;
        }

        /*
         * /etc/security/crypt.conf has 3 fields:
         * <algname>    <pathname>      [<name[=val]>[<name[=val]>]]
         */
        errno = 0;
        while (!(*found) &&
            ((fgets(line, sizeof (line), fconf) != NULL) && !feof(fconf))) {
                lineno++;
                /*
                 * Skip over comments
                 */
                if ((line[0] == '#') || (line[0] == '\n')) {
                        continue;
                }

                linelen = strlen(line);
                line[--linelen] = '\0'; /* chop the trailing \n */

                token = strtok_r(line, " \t", &lasts);
                if (token == NULL) {
                        continue;
                }
                if (strcmp(token, algname) == 0) {
                        *found = B_TRUE;
                }
        }
        if (!found) {
                errno = EINVAL;
                goto cleanup;
        }

        token = strtok_r(NULL, " \t", &lasts);
        if (token == NULL) {
                /*
                 * Broken config file
                 */
                syslog(LOG_ALERT, "crypt(3c): %s may be corrupt at line %d",
                    CRYPT_CONFFILE, lineno);
                *found = B_FALSE;
                errno = EINVAL;
                goto cleanup;
        }

        if ((pathname = isa_path(token)) == NULL) {
                if (errno != ENOMEM)
                        errno = EINVAL;
                *found = B_FALSE;
                goto cleanup;
        }

        if ((alg = malloc(sizeof (struct crypt_alg_s))) == NULL) {
                *found = B_FALSE;
                goto cleanup;
        }
        alg->a_libhandle = NULL;
        alg->a_genhash = NULL;
        alg->a_gensalt = NULL;
        alg->a_params = NULL;
        alg->a_nparams = 0;

        /*
         * The rest of the line is module specific params, space
         * seprated. We wait until after we have checked the module is
         * valid before parsing them into a_params, this saves us
         * having to free them later if there is a problem.
         */
        if ((alg->a_libhandle = dlopen(pathname, RTLD_NOW)) == NULL) {
                syslog(LOG_ERR, "crypt(3c) unable to dlopen %s: %s",
                    pathname, dlerror());
                errno = ELIBACC;
                *found = B_FALSE;
                goto cleanup;
        }

        alg->a_genhash =
            (char *(*)())dlsym(alg->a_libhandle, "crypt_genhash_impl");
        if (alg->a_genhash == NULL) {
                syslog(LOG_ERR, "crypt(3c) unable to find cryp_genhash_impl"
                    "symbol in %s: %s", pathname, dlerror());
                errno = ELIBACC;
                *found = B_FALSE;
                goto cleanup;
        }
        alg->a_gensalt =
            (char *(*)())dlsym(alg->a_libhandle, "crypt_gensalt_impl");
        if (alg->a_gensalt == NULL) {
                syslog(LOG_ERR, "crypt(3c) unable to find crypt_gensalt_impl"
                    "symbol in %s: %s", pathname, dlerror());
                errno = ELIBACC;
                *found = B_FALSE;
                goto cleanup;
        }

        /*
         * We have a good module so build the a_params if we have any.
         * Count how much space we need first and then allocate an array
         * to hold that many module params.
         */
        if (lasts != NULL) {
                int nparams = 0;
                char *tparams;
                char *tplasts;

                if ((tparams = strdup(lasts)) == NULL) {
                        *found = B_FALSE;
                        goto cleanup;
                }

                (void) strtok_r(tparams, " \t", &tplasts);
                do {
                        nparams++;
                } while (strtok_r(NULL, " \t", &tplasts) != NULL);
                free(tparams);

                alg->a_params = calloc(nparams + 1, sizeof (char *));
                if (alg->a_params == NULL) {
                        *found = B_FALSE;
                        goto cleanup;
                }

                while ((token = strtok_r(NULL, " \t", &lasts)) != NULL) {
                        alg->a_params[alg->a_nparams++] = token;
                }
        }

cleanup:
        if (*found == B_FALSE) {
                free_crypt_alg(alg);
                alg = NULL;
        }

        if (pathname != NULL) {
                free(pathname);
        }

        if (fconf != NULL) {
                (void) fclose(fconf);
        } else {
                (void) close(configfd);
        }

        return (alg);
}

static void
free_crypt_alg(struct crypt_alg_s *alg)
{
        if (alg == NULL)
                return;

        if (alg->a_libhandle != NULL) {
                (void) dlclose(alg->a_libhandle);
        }
        if (alg->a_nparams != 0) {
                free(alg->a_params);
        }
        free(alg);
}

static void
free_crypt_policy(struct crypt_policy_s *policy)
{
        if (policy == NULL)
                return;

        if (policy->cp_default != NULL) {
                bzero(policy->cp_default, strlen(policy->cp_default));
                free(policy->cp_default);
                policy->cp_default = NULL;
        }

        if (policy->cp_allow != NULL) {
                bzero(policy->cp_allow, strlen(policy->cp_allow));
                free(policy->cp_allow);
                policy->cp_allow = NULL;
        }

        if (policy->cp_deny != NULL) {
                bzero(policy->cp_deny, strlen(policy->cp_deny));
                free(policy->cp_deny);
                policy->cp_deny = NULL;
        }

        free(policy);
}


/*
 * isa_path - prepend the default dir or patch up the $ISA in path
 *      Caller is responsible for calling free(3c) on the result.
 */
static char *
isa_path(const char *path)
{
        char *ret = NULL;

        if ((path == NULL) || (strlen(path) > PATH_MAX)) {
                return (NULL);
        }

        ret = calloc(PATH_MAX, sizeof (char));

        /*
         * Module path doesn't start with "/" then prepend
         * the default search path CRYPT_MODULE_DIR (/usr/lib/security/$ISA)
         */
        if (path[0] != '/') {
                if (snprintf(ret, PATH_MAX, "%s%s", CRYPT_MODULE_DIR,
                    path) > PATH_MAX) {
                        free(ret);
                        return (NULL);
                }
        } else { /* patch up $ISA */
                char *isa;

                if ((isa = strstr(path, CRYPT_MODULE_ISA)) != NULL) {
                        *isa = '\0';
                        isa += strlen(CRYPT_MODULE_ISA);
                        if (snprintf(ret, PATH_MAX, "%s%s%s", path,
                            CRYPT_ISA_DIR, isa) > PATH_MAX) {
                                free(ret);
                                return (NULL);
                        }
                } else {
                        free(ret);
                        ret = strdup(path);
                }
        }

        return (ret);
}


/*ARGSUSED*/
static char *
_unix_crypt_gensalt(char *gsbuffer,
            size_t gsbufflen,
            const char *oldpuresalt,
            const struct passwd *userinfo,
            const char *argv[])
{
        static const char saltchars[] =
            "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
        struct timeval tv;

        (void) gettimeofday(&tv, NULL);
        srand48(tv.tv_sec ^ tv.tv_usec);
        gsbuffer[0] = saltchars[lrand48() % 64]; /* lrand48() is MT-SAFE */
        gsbuffer[1] = saltchars[lrand48() % 64]; /* lrand48() is MT-SAFE */
        gsbuffer[2] = '\0';

        return (gsbuffer);
}

/*
 * The rest of the code below comes from the old crypt.c and is the
 * implementation of the hardwired/fallback traditional algorithm
 * It has been otimized to take better advantage of MT features.
 *
 * It is included here to reduce the overhead of dlopen()
 * for the common case.
 */


/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */



/*
 * This program implements a data encryption algorithm to encrypt passwords.
 */

static mutex_t crypt_lock = DEFAULTMUTEX;
#define TSDBUFSZ        (66 + 16)

static const char IP[] = {
        58, 50, 42, 34, 26, 18, 10, 2,
        60, 52, 44, 36, 28, 20, 12, 4,
        62, 54, 46, 38, 30, 22, 14, 6,
        64, 56, 48, 40, 32, 24, 16, 8,
        57, 49, 41, 33, 25, 17, 9, 1,
        59, 51, 43, 35, 27, 19, 11, 3,
        61, 53, 45, 37, 29, 21, 13, 5,
        63, 55, 47, 39, 31, 23, 15, 7,
};

static const char FP[] = {
        40, 8, 48, 16, 56, 24, 64, 32,
        39, 7, 47, 15,  55, 23, 63, 31,
        38, 6, 46, 14, 54, 22, 62, 30,
        37, 5, 45, 13, 53, 21, 61, 29,
        36, 4, 44, 12, 52, 20, 60, 28,
        35, 3, 43, 11, 51, 19, 59, 27,
        34, 2, 42, 10, 50, 18, 58, 26,
        33, 1, 41, 9, 49, 17, 57, 25,
};

static const char PC1_C[] = {
        57, 49, 41, 33, 25, 17, 9,
        1, 58, 50, 42, 34, 26, 18,
        10, 2, 59, 51, 43, 35, 27,
        19, 11, 3, 60, 52, 44, 36,
};

static const char PC1_D[] = {
        63, 55, 47, 39, 31, 23, 15,
        7, 62, 54, 46, 38, 30, 22,
        14, 6, 61, 53, 45, 37, 29,
        21, 13, 5, 28, 20, 12, 4,
};

static const char shifts[] = {
        1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1,
};

static const char PC2_C[] = {
        14, 17, 11, 24, 1, 5,
        3, 28, 15, 6, 21, 10,
        23, 19, 12, 4, 26, 8,
        16, 7, 27, 20, 13, 2,
};

static const char PC2_D[] = {
        41, 52, 31, 37, 47, 55,
        30, 40, 51, 45, 33, 48,
        44, 49, 39, 56, 34, 53,
        46, 42, 50, 36, 29, 32,
};

static char C[28];
static char D[28];
static char *KS;

static char E[48];
static const char e2[] = {
        32, 1, 2, 3, 4, 5,
        4, 5, 6, 7, 8, 9,
        8, 9, 10, 11, 12, 13,
        12, 13, 14, 15, 16, 17,
        16, 17, 18, 19, 20, 21,
        20, 21, 22, 23, 24, 25,
        24, 25, 26, 27, 28, 29,
        28, 29, 30, 31, 32, 1,
};

/*
 * The KS array (768 bytes) is allocated once, and only if
 * one of _unix_crypt(), encrypt() or setkey() is called.
 * The complexity below is due to the fact that calloc()
 * must not be called while holding any locks.
 */
static int
allocate_KS(void)
{
        char *ks;
        int failed;
        int assigned;

        if (KS != NULL) {               /* already allocated */
                membar_consumer();
                return (0);
        }

        ks = calloc(16, 48 * sizeof (char));
        failed = 0;
        lmutex_lock(&crypt_lock);
        if (KS != NULL) {       /* someone else got here first */
                assigned = 0;
        } else {
                assigned = 1;
                membar_producer();
                if ((KS = ks) == NULL)  /* calloc() failed */
                        failed = 1;
        }
        lmutex_unlock(&crypt_lock);
        if (!assigned)
                free(ks);
        return (failed);
}

static void
unlocked_setkey(const char *key)
{
        int i, j, k;
        char t;

        for (i = 0; i < 28; i++) {
                C[i] = key[PC1_C[i]-1];
                D[i] = key[PC1_D[i]-1];
        }
        for (i = 0; i < 16; i++) {
                for (k = 0; k < shifts[i]; k++) {
                        t = C[0];
                        for (j = 0; j < 28-1; j++)
                                C[j] = C[j+1];
                        C[27] = t;
                        t = D[0];
                        for (j = 0; j < 28-1; j++)
                                D[j] = D[j+1];
                        D[27] = t;
                }
                for (j = 0; j < 24; j++) {
                        int index = i * 48;

                        *(KS+index+j) = C[PC2_C[j]-1];
                        *(KS+index+j+24) = D[PC2_D[j]-28-1];
                }
        }
        for (i = 0; i < 48; i++)
                E[i] = e2[i];
}

static const char S[8][64] = {
        14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
        0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
        4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
        15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13,

        15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
        3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
        0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
        13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9,

        10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
        13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
        13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
        1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12,

        7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
        13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
        10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
        3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14,

        2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
        14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
        4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
        11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3,

        12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
        10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
        9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
        4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13,

        4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
        13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
        1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
        6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12,

        13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
        1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
        7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
        2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11,
};

static const char P[] = {
        16, 7, 20, 21,
        29, 12, 28, 17,
        1, 15, 23, 26,
        5, 18, 31, 10,
        2, 8, 24, 14,
        32, 27, 3, 9,
        19, 13, 30, 6,
        22, 11, 4, 25,
};

static char L[64];
static char tempL[32];
static char f[32];

static char preS[48];

/*ARGSUSED*/
static void
unlocked_encrypt(char *block, int fake)
{
        int     i;
        int t, j, k;
        char *R = &L[32];

        for (j = 0; j < 64; j++)
                L[j] = block[IP[j]-1];
        for (i = 0; i < 16; i++) {
                int index = i * 48;

                for (j = 0; j < 32; j++)
                        tempL[j] = R[j];
                for (j = 0; j < 48; j++)
                        preS[j] = R[E[j]-1] ^ *(KS+index+j);
                for (j = 0; j < 8; j++) {
                        t = 6 * j;
                        k = S[j][(preS[t+0]<<5) +
                            (preS[t+1]<<3) +
                            (preS[t+2]<<2) +
                            (preS[t+3]<<1) +
                            (preS[t+4]<<0) +
                            (preS[t+5]<<4)];
                        t = 4*j;
                        f[t+0] = (k>>3)&01;
                        f[t+1] = (k>>2)&01;
                        f[t+2] = (k>>1)&01;
                        f[t+3] = (k>>0)&01;
                }
                for (j = 0; j < 32; j++)
                        R[j] = L[j] ^ f[P[j]-1];
                for (j = 0; j < 32; j++)
                        L[j] = tempL[j];
        }
        for (j = 0; j < 32; j++) {
                t = L[j];
                L[j] = R[j];
                R[j] = (char)t;
        }
        for (j = 0; j < 64; j++)
                block[j] = L[FP[j]-1];
}

char *
_unix_crypt(const char *pw, const char *salt, char *iobuf)
{
        int c, i, j;
        char temp;
        char *block;

        block = iobuf + 16;

        if (iobuf == 0) {
                errno = ENOMEM;
                return (NULL);
        }
        if (allocate_KS() != 0)
                return (NULL);
        lmutex_lock(&crypt_lock);
        for (i = 0; i < 66; i++)
                block[i] = 0;
        for (i = 0; (c = *pw) != '\0' && i < 64; pw++) {
                for (j = 0; j < 7; j++, i++)
                        block[i] = (c>>(6-j)) & 01;
                i++;
        }

        unlocked_setkey(block);

        for (i = 0; i < 66; i++)
                block[i] = 0;

        for (i = 0; i < 2; i++) {
                c = *salt++;
                iobuf[i] = (char)c;
                if (c > 'Z')
                        c -= 6;
                if (c > '9')
                        c -= 7;
                c -= '.';
                for (j = 0; j < 6; j++) {
                        if ((c>>j) & 01) {
                                temp = E[6*i+j];
                                E[6*i+j] = E[6*i+j+24];
                                E[6*i+j+24] = temp;
                        }
                }
        }

        for (i = 0; i < 25; i++)
                unlocked_encrypt(block, 0);

        lmutex_unlock(&crypt_lock);
        for (i = 0; i < 11; i++) {
                c = 0;
                for (j = 0; j < 6; j++) {
                        c <<= 1;
                        c |= block[6*i+j];
                }
                c += '.';
                if (c > '9')
                        c += 7;
                if (c > 'Z')
                        c += 6;
                iobuf[i+2] = (char)c;
        }
        iobuf[i+2] = 0;
        if (iobuf[1] == 0)
                iobuf[1] = iobuf[0];
        return (iobuf);
}


/*ARGSUSED*/
void
encrypt(char *block, int fake)
{
        if (fake != 0) {
                errno = ENOSYS;
                return;
        }
        if (allocate_KS() != 0)
                return;
        lmutex_lock(&crypt_lock);
        unlocked_encrypt(block, fake);
        lmutex_unlock(&crypt_lock);
}


void
setkey(const char *key)
{
        if (allocate_KS() != 0)
                return;
        lmutex_lock(&crypt_lock);
        unlocked_setkey(key);
        lmutex_unlock(&crypt_lock);
}