/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 *
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 *
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 *
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 *
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 *
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 *
 * @(#)keyserv.c        1.15    94/04/25 SMI
 * $FreeBSD: src/usr.sbin/keyserv/keyserv.c,v 1.12 2007/11/07 10:53:35 kevlo Exp $
 */

/*
 * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
 */

/*
 * Keyserver
 * Store secret keys per uid. Do public key encryption and decryption
 * operations. Generate "random" keys.
 * Do not talk to anything but a local root
 * process on the local transport only
 */

#include <err.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <rpc/rpc.h>
#include <sys/param.h>
#include <rpc/des_crypt.h>
#include <rpc/des.h>
#include <rpc/key_prot.h>
#include <rpcsvc/crypt.h>
#include "keyserv.h"

#ifndef NGROUPS
#define NGROUPS 16
#endif

#ifndef KEYSERVSOCK
#define KEYSERVSOCK "/var/run/keyservsock"
#endif

static void randomize( des_block * );
static void usage( void );
static int getrootkey( des_block *, int );
static int root_auth( SVCXPRT *, struct svc_req * );

#ifdef DEBUG
static int debugging = 1;
#else
static int debugging = 0;
#endif

static void keyprogram();
static des_block masterkey;
char *getenv();
static char ROOTKEY[] = "/etc/.rootkey";

/*
 * Hack to allow the keyserver to use AUTH_DES (for authenticated
 * NIS+ calls, for example).  The only functions that get called
 * are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
 *
 * The approach is to have the keyserver fill in pointers to local
 * implementations of these functions, and to call those in key_call().
 */

extern cryptkeyres *(*__key_encryptsession_pk_LOCAL)();
extern cryptkeyres *(*__key_decryptsession_pk_LOCAL)();
extern des_block *(*__key_gendes_LOCAL)();
extern int (*__des_crypt_LOCAL)();

cryptkeyres *key_encrypt_pk_2_svc_prog( uid_t, cryptkeyarg2 * );
cryptkeyres *key_decrypt_pk_2_svc_prog( uid_t, cryptkeyarg2 * );
des_block *key_gen_1_svc_prog( void *, struct svc_req * );

int
main(int argc, char **argv)
{
        int nflag = 0;
        int c;
        int warn = 0;
        char *path = NULL;
        void *localhandle;
        SVCXPRT *transp;
        struct netconfig *nconf = NULL;

        __key_encryptsession_pk_LOCAL = &key_encrypt_pk_2_svc_prog;
        __key_decryptsession_pk_LOCAL = &key_decrypt_pk_2_svc_prog;
        __key_gendes_LOCAL = &key_gen_1_svc_prog;

        while ((c = getopt(argc, argv, "ndDvp:")) != -1)
                switch (c) {
                case 'n':
                        nflag++;
                        break;
                case 'd':
                        pk_nodefaultkeys();
                        break;
                case 'D':
                        debugging = 1;
                        break;
                case 'v':
                        warn = 1;
                        break;
                case 'p':
                        path = optarg;
                        break;
                default:
                        usage();
                }

        load_des(warn, path);
        __des_crypt_LOCAL = _my_crypt;
        if (svc_auth_reg(AUTH_DES, _svcauth_des) == -1)
                errx(1, "failed to register AUTH_DES authenticator");

        if (optind != argc) {
                usage();
        }

        /*
         * Initialize
         */
        umask(S_IXUSR|S_IXGRP|S_IXOTH);
        if (geteuid() != 0)
                errx(1, "keyserv must be run as root");
        setmodulus(HEXMODULUS);
        getrootkey(&masterkey, nflag);

        rpcb_unset(KEY_PROG, KEY_VERS, NULL);
        rpcb_unset(KEY_PROG, KEY_VERS2, NULL);

        if (svc_create(keyprogram, KEY_PROG, KEY_VERS,
                "netpath") == 0) {
                fprintf(stderr, "%s: unable to create service\n", argv[0]);
                exit(1);
        }

        if (svc_create(keyprogram, KEY_PROG, KEY_VERS2,
        "netpath") == 0) {
                fprintf(stderr, "%s: unable to create service\n", argv[0]);
                exit(1);
        }

        localhandle = setnetconfig();
        while ((nconf = getnetconfig(localhandle)) != NULL) {
                if (nconf->nc_protofmly != NULL &&
                    strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0)
                        break;
        }

        if (nconf == NULL)
                errx(1, "getnetconfig: %s", nc_sperror());

        unlink(KEYSERVSOCK);
        rpcb_unset(CRYPT_PROG, CRYPT_VERS, nconf);
        transp = svcunix_create(RPC_ANYSOCK, 0, 0, KEYSERVSOCK);
        if (transp == NULL)
                errx(1, "cannot create AF_LOCAL service");
        if (!svc_reg(transp, KEY_PROG, KEY_VERS, keyprogram, nconf))
                errx(1, "unable to register (KEY_PROG, KEY_VERS, unix)");
        if (!svc_reg(transp, KEY_PROG, KEY_VERS2, keyprogram, nconf))
                errx(1, "unable to register (KEY_PROG, KEY_VERS2, unix)");
        if (!svc_reg(transp, CRYPT_PROG, CRYPT_VERS, crypt_prog_1, nconf))
                errx(1, "unable to register (CRYPT_PROG, CRYPT_VERS, unix)");

        endnetconfig(localhandle);

        umask(066);     /* paranoia */

        if (!debugging) {
                daemon(0,0);
        }

        signal(SIGPIPE, SIG_IGN);

        svc_run();
        abort();
        /* NOTREACHED */
}

/*
 * In the event that we don't get a root password, we try to
 * randomize the master key the best we can
 */
static void
randomize(des_block *master)
{
#ifdef KEYSERV_RANDOM
        master->key.low = arc4random();
        master->key.high = arc4random();
#else
        /* use stupid dangerous bad rand() */
        sranddev();
        master->key.low = rand();
        master->key.high = rand();
#endif
}

/*
 * Try to get root's secret key, by prompting if terminal is a tty, else trying
 * from standard input.
 * Returns 1 on success.
 */
static int
getrootkey(des_block *master, int prompt)
{
        char *passwd;
        char name[MAXNETNAMELEN + 1];
        char secret[HEXKEYBYTES];
        key_netstarg netstore;
        int fd;

        if (!prompt) {
                /*
                 * Read secret key out of ROOTKEY
                 */
                fd = open(ROOTKEY, O_RDONLY, 0);
                if (fd < 0) {
                        randomize(master);
                        return (0);
                }
                if (read(fd, secret, HEXKEYBYTES) < HEXKEYBYTES) {
                        warnx("the key read from %s was too short", ROOTKEY);
                        close(fd);
                        return (0);
                }
                close(fd);
                if (!getnetname(name)) {
                    warnx(
        "failed to generate host's netname when establishing root's key");
                    return (0);
                }
                memcpy(netstore.st_priv_key, secret, HEXKEYBYTES);
                memset(netstore.st_pub_key, 0, HEXKEYBYTES);
                netstore.st_netname = name;
                if (pk_netput(0, &netstore) != KEY_SUCCESS) {
                    warnx("could not set root's key and netname");
                    return (0);
                }
                return (1);
        }
        /*
         * Decrypt yellow pages publickey entry to get secret key
         */
        passwd = getpass("root password:");
        passwd2des(passwd, (char *)master);
        getnetname(name);
        if (!getsecretkey(name, secret, passwd)) {
                warnx("can't find %s's secret key", name);
                return (0);
        }
        if (secret[0] == 0) {
                warnx("password does not decrypt secret key for %s", name);
                return (0);
        }
        pk_setkey(0, secret);
        /*
         * Store it for future use in $ROOTKEY, if possible
         */
        fd = open(ROOTKEY, O_WRONLY|O_TRUNC|O_CREAT, 0);
        if (fd > 0) {
                char newline = '\n';

                write(fd, secret, strlen(secret));
                write(fd, &newline, sizeof (newline));
                close(fd);
        }
        return (1);
}

/*
 * Procedures to implement RPC service
 */
char *
strstatus(keystatus status)
{
        switch (status) {
        case KEY_SUCCESS:
                return ("KEY_SUCCESS");
        case KEY_NOSECRET:
                return ("KEY_NOSECRET");
        case KEY_UNKNOWN:
                return ("KEY_UNKNOWN");
        case KEY_SYSTEMERR:
                return ("KEY_SYSTEMERR");
        default:
                return ("(bad result code)");
        }
}

keystatus *
key_set_1_svc_prog(uid_t uid, keybuf key)
{
        static keystatus status;

        if (debugging) {
                fprintf(stderr, "set(%d, %.*s) = ", uid,
                                (int) sizeof (keybuf), key);
        }
        status = pk_setkey(uid, key);
        if (debugging) {
                fprintf(stderr, "%s\n", strstatus(status));
                fflush(stderr);
        }
        return (&status);
}

cryptkeyres *
key_encrypt_pk_2_svc_prog(uid_t uid, cryptkeyarg2 *arg)
{
        static cryptkeyres res;

        if (debugging) {
                fprintf(stderr, "encrypt(%d, %s, %08x%08x) = ", uid,
                                arg->remotename, arg->deskey.key.high,
                                arg->deskey.key.low);
        }
        res.cryptkeyres_u.deskey = arg->deskey;
        res.status = pk_encrypt(uid, arg->remotename, &(arg->remotekey),
                                &res.cryptkeyres_u.deskey);
        if (debugging) {
                if (res.status == KEY_SUCCESS) {
                        fprintf(stderr, "%08x%08x\n",
                                        res.cryptkeyres_u.deskey.key.high,
                                        res.cryptkeyres_u.deskey.key.low);
                } else {
                        fprintf(stderr, "%s\n", strstatus(res.status));
                }
                fflush(stderr);
        }
        return (&res);
}

cryptkeyres *
key_decrypt_pk_2_svc_prog(uid_t uid, cryptkeyarg2 *arg)
{
        static cryptkeyres res;

        if (debugging) {
                fprintf(stderr, "decrypt(%d, %s, %08x%08x) = ", uid,
                                arg->remotename, arg->deskey.key.high,
                                arg->deskey.key.low);
        }
        res.cryptkeyres_u.deskey = arg->deskey;
        res.status = pk_decrypt(uid, arg->remotename, &(arg->remotekey),
                                &res.cryptkeyres_u.deskey);
        if (debugging) {
                if (res.status == KEY_SUCCESS) {
                        fprintf(stderr, "%08x%08x\n",
                                        res.cryptkeyres_u.deskey.key.high,
                                        res.cryptkeyres_u.deskey.key.low);
                } else {
                        fprintf(stderr, "%s\n", strstatus(res.status));
                }
                fflush(stderr);
        }
        return (&res);
}

keystatus *
key_net_put_2_svc_prog(uid_t uid, key_netstarg *arg)
{
        static keystatus status;

        if (debugging) {
                fprintf(stderr, "net_put(%s, %.*s, %.*s) = ",
                        arg->st_netname, (int)sizeof (arg->st_pub_key),
                        arg->st_pub_key, (int)sizeof (arg->st_priv_key),
                        arg->st_priv_key);
        }

        status = pk_netput(uid, arg);

        if (debugging) {
                fprintf(stderr, "%s\n", strstatus(status));
                fflush(stderr);
        }

        return (&status);
}

key_netstres *
key_net_get_2_svc_prog(uid_t uid, void *arg)
{
        static key_netstres keynetname;

        if (debugging)
                fprintf(stderr, "net_get(%d) = ", uid);

        keynetname.status = pk_netget(uid, &keynetname.key_netstres_u.knet);
        if (debugging) {
                if (keynetname.status == KEY_SUCCESS) {
                        fprintf(stderr, "<%s, %.*s, %.*s>\n",
                        keynetname.key_netstres_u.knet.st_netname,
                        (int)sizeof (keynetname.key_netstres_u.knet.st_pub_key),
                        keynetname.key_netstres_u.knet.st_pub_key,
                        (int)sizeof (keynetname.key_netstres_u.knet.st_priv_key),
                        keynetname.key_netstres_u.knet.st_priv_key);
                } else {
                        fprintf(stderr, "NOT FOUND\n");
                }
                fflush(stderr);
        }

        return (&keynetname);

}

cryptkeyres *
key_get_conv_2_svc_prog(uid_t uid, keybuf arg)
{
        static cryptkeyres  res;

        if (debugging)
                fprintf(stderr, "get_conv(%d, %.*s) = ", uid,
                        (int)sizeof (keybuf), arg);


        res.status = pk_get_conv_key(uid, arg, &res);

        if (debugging) {
                if (res.status == KEY_SUCCESS) {
                        fprintf(stderr, "%08x%08x\n",
                                res.cryptkeyres_u.deskey.key.high,
                                res.cryptkeyres_u.deskey.key.low);
                } else {
                        fprintf(stderr, "%s\n", strstatus(res.status));
                }
                fflush(stderr);
        }
        return (&res);
}


cryptkeyres *
key_encrypt_1_svc_prog(uid_t uid, cryptkeyarg *arg)
{
        static cryptkeyres res;

        if (debugging) {
                fprintf(stderr, "encrypt(%d, %s, %08x%08x) = ", uid,
                                arg->remotename, arg->deskey.key.high,
                                arg->deskey.key.low);
        }
        res.cryptkeyres_u.deskey = arg->deskey;
        res.status = pk_encrypt(uid, arg->remotename, NULL,
                                &res.cryptkeyres_u.deskey);
        if (debugging) {
                if (res.status == KEY_SUCCESS) {
                        fprintf(stderr, "%08x%08x\n",
                                        res.cryptkeyres_u.deskey.key.high,
                                        res.cryptkeyres_u.deskey.key.low);
                } else {
                        fprintf(stderr, "%s\n", strstatus(res.status));
                }
                fflush(stderr);
        }
        return (&res);
}

cryptkeyres *
key_decrypt_1_svc_prog(uid_t uid, cryptkeyarg *arg)
{
        static cryptkeyres res;

        if (debugging) {
                fprintf(stderr, "decrypt(%d, %s, %08x%08x) = ", uid,
                                arg->remotename, arg->deskey.key.high,
                                arg->deskey.key.low);
        }
        res.cryptkeyres_u.deskey = arg->deskey;
        res.status = pk_decrypt(uid, arg->remotename, NULL,
                                &res.cryptkeyres_u.deskey);
        if (debugging) {
                if (res.status == KEY_SUCCESS) {
                        fprintf(stderr, "%08x%08x\n",
                                        res.cryptkeyres_u.deskey.key.high,
                                        res.cryptkeyres_u.deskey.key.low);
                } else {
                        fprintf(stderr, "%s\n", strstatus(res.status));
                }
                fflush(stderr);
        }
        return (&res);
}

/* ARGSUSED */
des_block *
key_gen_1_svc_prog(void *v, struct svc_req *s)
{
        struct timeval time;
        static des_block keygen;
        static des_block key;

        gettimeofday(&time, NULL);
        keygen.key.high += (time.tv_sec ^ time.tv_usec);
        keygen.key.low += (time.tv_sec ^ time.tv_usec);
        ecb_crypt((char *)&masterkey, (char *)&keygen, sizeof (keygen),
                DES_ENCRYPT | DES_HW);
        key = keygen;
        des_setparity((char *)&key);
        if (debugging) {
                fprintf(stderr, "gen() = %08x%08x\n", key.key.high,
                                        key.key.low);
                fflush(stderr);
        }
        return (&key);
}

getcredres *
key_getcred_1_svc_prog(uid_t uid, netnamestr *name)
{
        static getcredres res;
        static u_int gids[NGROUPS];
        struct unixcred *cred;

        cred = &res.getcredres_u.cred;
        cred->gids.gids_val = gids;
        if (!netname2user(*name, (uid_t *) &cred->uid, (gid_t *) &cred->gid,
                        (int *)&cred->gids.gids_len, (gid_t *)gids)) {
                res.status = KEY_UNKNOWN;
        } else {
                res.status = KEY_SUCCESS;
        }
        if (debugging) {
                fprintf(stderr, "getcred(%s) = ", *name);
                if (res.status == KEY_SUCCESS) {
                        fprintf(stderr, "uid=%d, gid=%d, grouplen=%d\n",
                                cred->uid, cred->gid, cred->gids.gids_len);
                } else {
                        fprintf(stderr, "%s\n", strstatus(res.status));
                }
                fflush(stderr);
        }
        return (&res);
}

/*
 * RPC boilerplate
 */
static void
keyprogram(struct svc_req *rqstp, SVCXPRT *transp)
{
        union {
                keybuf key_set_1_arg;
                cryptkeyarg key_encrypt_1_arg;
                cryptkeyarg key_decrypt_1_arg;
                netnamestr key_getcred_1_arg;
                cryptkeyarg key_encrypt_2_arg;
                cryptkeyarg key_decrypt_2_arg;
                netnamestr key_getcred_2_arg;
                cryptkeyarg2 key_encrypt_pk_2_arg;
                cryptkeyarg2 key_decrypt_pk_2_arg;
                key_netstarg key_net_put_2_arg;
                netobj  key_get_conv_2_arg;
        } argument;
        char *result;
        xdrproc_t xdr_argument, xdr_result;
        char *(*local) ();
        uid_t uid = -1;
        int check_auth;

        switch (rqstp->rq_proc) {
        case NULLPROC:
                svc_sendreply(transp, (xdrproc_t)xdr_void, NULL);
                return;

        case KEY_SET:
                xdr_argument = (xdrproc_t)xdr_keybuf;
                xdr_result = (xdrproc_t)xdr_int;
                local = (char *(*)()) key_set_1_svc_prog;
                check_auth = 1;
                break;

        case KEY_ENCRYPT:
                xdr_argument = (xdrproc_t)xdr_cryptkeyarg;
                xdr_result = (xdrproc_t)xdr_cryptkeyres;
                local = (char *(*)()) key_encrypt_1_svc_prog;
                check_auth = 1;
                break;

        case KEY_DECRYPT:
                xdr_argument = (xdrproc_t)xdr_cryptkeyarg;
                xdr_result = (xdrproc_t)xdr_cryptkeyres;
                local = (char *(*)()) key_decrypt_1_svc_prog;
                check_auth = 1;
                break;

        case KEY_GEN:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_des_block;
                local = (char *(*)()) key_gen_1_svc_prog;
                check_auth = 0;
                break;

        case KEY_GETCRED:
                xdr_argument = (xdrproc_t)xdr_netnamestr;
                xdr_result = (xdrproc_t)xdr_getcredres;
                local = (char *(*)()) key_getcred_1_svc_prog;
                check_auth = 0;
                break;

        case KEY_ENCRYPT_PK:
                xdr_argument = (xdrproc_t)xdr_cryptkeyarg2;
                xdr_result = (xdrproc_t)xdr_cryptkeyres;
                local = (char *(*)()) key_encrypt_pk_2_svc_prog;
                check_auth = 1;
                break;

        case KEY_DECRYPT_PK:
                xdr_argument = (xdrproc_t)xdr_cryptkeyarg2;
                xdr_result = (xdrproc_t)xdr_cryptkeyres;
                local = (char *(*)()) key_decrypt_pk_2_svc_prog;
                check_auth = 1;
                break;


        case KEY_NET_PUT:
                xdr_argument = (xdrproc_t)xdr_key_netstarg;
                xdr_result = (xdrproc_t)xdr_keystatus;
                local = (char *(*)()) key_net_put_2_svc_prog;
                check_auth = 1;
                break;

        case KEY_NET_GET:
                xdr_argument = (xdrproc_t) xdr_void;
                xdr_result = (xdrproc_t)xdr_key_netstres;
                local = (char *(*)()) key_net_get_2_svc_prog;
                check_auth = 1;
                break;

        case KEY_GET_CONV:
                xdr_argument = (xdrproc_t) xdr_keybuf;
                xdr_result = (xdrproc_t)xdr_cryptkeyres;
                local = (char *(*)()) key_get_conv_2_svc_prog;
                check_auth = 1;
                break;

        default:
                svcerr_noproc(transp);
                return;
        }
        if (check_auth) {
                if (root_auth(transp, rqstp) == 0) {
                        if (debugging) {
                                fprintf(stderr,
                                        "not local privileged process\n");
                        }
                        svcerr_weakauth(transp);
                        return;
                }
                if (rqstp->rq_cred.oa_flavor != AUTH_SYS) {
                        if (debugging) {
                                fprintf(stderr, "not unix authentication\n");
                        }
                        svcerr_weakauth(transp);
                        return;
                }
                uid = ((struct authsys_parms *)rqstp->rq_clntcred)->aup_uid;
        }

        memset(&argument, 0, sizeof (argument));
        if (!svc_getargs(transp, xdr_argument, &argument)) {
                svcerr_decode(transp);
                return;
        }
        result = (*local) (uid, &argument);
        if (!svc_sendreply(transp, xdr_result, result)) {
                if (debugging)
                        fprintf(stderr, "unable to reply\n");
                svcerr_systemerr(transp);
        }
        if (!svc_freeargs(transp, xdr_argument, &argument)) {
                if (debugging)
                        fprintf(stderr, "unable to free arguments\n");
                exit(1);
        }
        return;
}

static int
root_auth(SVCXPRT *trans, struct svc_req *rqstp)
{
        uid_t uid;
        struct sockaddr *remote;

        remote = svc_getrpccaller(trans)->buf;
        if (remote->sa_family != AF_UNIX) {
                if (debugging)
                        fprintf(stderr, "client didn't use AF_UNIX\n");
                return (0);
        }

        if (__rpc_get_local_uid(trans, &uid) < 0) {
                if (debugging)
                        fprintf(stderr, "__rpc_get_local_uid failed\n");
                return (0);
        }

        if (debugging)
                fprintf(stderr, "local_uid  %d\n", uid);
        if (uid == 0)
                return (1);
        if (rqstp->rq_cred.oa_flavor == AUTH_SYS) {
                if (((uid_t) ((struct authunix_parms *)
                        rqstp->rq_clntcred)->aup_uid)
                        == uid) {
                        return (1);
                } else {
                        if (debugging)
                                fprintf(stderr,
                        "local_uid  %d mismatches auth %u\n", uid,
((uid_t) ((struct authunix_parms *)rqstp->rq_clntcred)->aup_uid));
                        return (0);
                }
        } else {
                if (debugging)
                        fprintf(stderr, "Not auth sys\n");
                return (0);
        }
}

static void
usage(void)
{
        fprintf(stderr, "usage: keyserv [-n] [-D] [-d] [-v] [-p path]\n");
        fprintf(stderr, "-d disables the use of default keys\n");
        exit(1);
}