/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 */

#include "defs.h"
#include <string.h>
#include <setjmp.h>
#include <netdb.h>
#include <signal.h>
#include <krb5defs.h>

#ifndef RDIST
#ifdef SYSV
/*
 * Historically, the rdist program has had the following hard-coded
 * pathname.  Some operating systems attempt to "improve" the
 * directory layout, in the process re-locating the rdist binary
 * to some other location.  However, the first original implementation
 * sets a standard of sorts.  In order to interoperate with other
 * systems, our implementation must do two things: It must provide
 * the an rdist binary at the pathname below, and it must use this
 * pathname when executing rdist on remote systems via the rcmd()
 * library.  Thus the hard-coded path name below can never be changed.
 */
#endif /* SYSV */
#define RDIST "/usr/ucb/rdist"
#endif

FILE    *lfp;                   /* log file for recording files updated */
struct  subcmd *subcmds;        /* list of sub-commands for current cmd */
jmp_buf env;

void    cleanup();
void    lostconn();
static int      init_service(int);
static struct servent *sp;

static void notify(char *file, char *rhost, struct namelist *to, time_t lmod);
static void rcmptime(struct stat *st);
static void cmptime(char *name);
static void dodcolon(char **filev, struct namelist *files, char *stamp,
    struct subcmd *cmds);
static void closeconn(void);
static void doarrow(char **filev, struct namelist *files, char *rhost,
    struct subcmd *cmds);
static int makeconn(char *rhost);
static int okname(char *name);

#ifdef SYSV
#include <libgen.h>

static char *recomp;
static char *errstring = "regcmp failed for some unknown reason";

char *
re_comp(char *s)
{
        if ((int)recomp != 0)
                free(recomp);
        recomp = regcmp(s, (char *)0);
        if (recomp == NULL)
                return (errstring);
        else
                return ((char *)0);
}


static int
re_exec(char *s)
{
        if ((int)recomp == 0)
                return (-1);
        if (regex(recomp, s) == NULL)
                return (0);
        else
                return (1);
}
#endif /* SYSV */

/*
 * Do the commands in cmds (initialized by yyparse).
 */
void
docmds(char **dhosts, int argc, char **argv)
{
        struct cmd *c;
        struct namelist *f;
        char **cpp;
        extern struct cmd *cmds;

        /* protect backgrounded rdist */
        if (signal(SIGINT, SIG_IGN) != SIG_IGN)
                (void) signal(SIGINT, cleanup);

        /* ... and running via nohup(1) */
        if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
                (void) signal(SIGHUP, cleanup);
        if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
                (void) signal(SIGQUIT, cleanup);

        (void) signal(SIGTERM, cleanup);

        if (debug) {
                if (!cmds)
                        printf("docmds:  cmds == NULL\n");
                else {
                        printf("docmds:  cmds ");
                        prcmd(cmds);
                }
        }
        for (c = cmds; c != NULL; c = c->c_next) {
                if (dhosts != NULL && *dhosts != NULL) {
                        for (cpp = dhosts; *cpp; cpp++)
                                if (strcmp(c->c_name, *cpp) == 0)
                                        goto fndhost;
                        continue;
                }
        fndhost:
                if (argc) {
                        for (cpp = argv; *cpp; cpp++) {
                                if (c->c_label != NULL &&
                                    strcmp(c->c_label, *cpp) == 0) {
                                        cpp = NULL;
                                        goto found;
                                }
                                for (f = c->c_files; f != NULL; f = f->n_next)
                                        if (strcmp(f->n_name, *cpp) == 0)
                                                goto found;
                        }
                        continue;
                } else
                        cpp = NULL;
        found:
                switch (c->c_type) {
                case ARROW:
                        doarrow(cpp, c->c_files, c->c_name, c->c_cmds);
                        break;
                case DCOLON:
                        dodcolon(cpp, c->c_files, c->c_name, c->c_cmds);
                        break;
                default:
                        fatal("illegal command type %d\n", c->c_type);
                }
        }
        closeconn();
}

/*
 * Process commands for sending files to other machines.
 */
static void
doarrow(char **filev, struct namelist *files, char *rhost, struct subcmd *cmds)
{
        struct namelist *f;
        struct subcmd *sc;
        char **cpp;
        int n, ddir, opts = options;

        if (debug)
                printf("doarrow(%x, %s, %x)\n", files, rhost, cmds);

        if (files == NULL) {
                error("no files to be updated\n");
                return;
        }

        subcmds = cmds;
        ddir = files->n_next != NULL;   /* destination is a directory */
        if (nflag)
                printf("updating host %s\n", rhost);
        else {
                if (setjmp(env))
                        goto done;
                (void) signal(SIGPIPE, lostconn);
                if (!makeconn(rhost))
                        return;
                if (!nflag)
                        if ((lfp = fopen(Tmpfile, "w")) == NULL) {
                                fatal("cannot open %s\n", Tmpfile);
                                exit(1);
                        }
        }
        for (f = files; f != NULL; f = f->n_next) {
                if (filev) {
                        for (cpp = filev; *cpp; cpp++)
                                if (strcmp(f->n_name, *cpp) == 0)
                                        goto found;
                        continue;
                }
        found:
                n = 0;
                for (sc = cmds; sc != NULL; sc = sc->sc_next) {
                        if (sc->sc_type != INSTALL)
                                continue;
                        n++;
                        install(f->n_name, sc->sc_name,
                            sc->sc_name == NULL ? 0 : ddir, sc->sc_options);
                        opts = sc->sc_options;
                }
                if (n == 0)
                        install(f->n_name, NULL, 0, options);
        }
done:
        if (!nflag) {
                (void) signal(SIGPIPE, cleanup);
                (void) fclose(lfp);
                lfp = NULL;
        }
        for (sc = cmds; sc != NULL; sc = sc->sc_next)
                if (sc->sc_type == NOTIFY)
                        notify(Tmpfile, rhost, sc->sc_args, 0);
        if (!nflag) {
                (void) unlink(Tmpfile);
                for (; ihead != NULL; ihead = ihead->nextp) {
                        free(ihead);
                        if ((opts & IGNLNKS) || ihead->count == 0)
                                continue;
                        log(lfp, "%s: Warning: missing links\n",
                            ihead->pathname);
                }
        }
}

static int
init_service(int krb5flag)
{
        boolean_t success = B_FALSE;

        if (krb5flag > 0) {
                if ((sp = getservbyname("kshell", "tcp")) == NULL) {
                        fatal("kshell/tcp: unknown service");
                        (void) fprintf(stderr,
                            gettext("trying shell/tcp service...\n"));
                } else {
                        success = B_TRUE;
                }
        } else {
                if ((sp = getservbyname("shell", "tcp")) == NULL) {
                        fatal("shell/tcp: unknown service");
                        exit(1);
                } else {
                        success = B_TRUE;
                }
        }
        return (success);
}
/*
 * Create a connection to the rdist server on the machine rhost.
 */
static int
makeconn(char *rhost)
{
        char *ruser, *cp;
        static char *cur_host = NULL;
        static int port = -1;
        char tuser[20];
        int n;
        extern char user[];

        if (debug)
                printf("makeconn(%s)\n", rhost);

        if (cur_host != NULL && rem >= 0) {
                if (strcmp(cur_host, rhost) == 0)
                        return (1);
                closeconn();
        }
        cur_host = rhost;
        cp = index(rhost, '@');
        if (cp != NULL) {
                char c = *cp;

                *cp = '\0';
                strncpy(tuser, rhost, sizeof (tuser)-1);
                *cp = c;
                rhost = cp + 1;
                ruser = tuser;
                if (*ruser == '\0')
                        ruser = user;
                else if (!okname(ruser))
                        return (0);
        } else
                ruser = user;
        if (!qflag)
                printf("updating host %s\n", rhost);
        (void) snprintf(buf, RDIST_BUFSIZ, "%s%s -Server%s",
            encrypt_flag ? "-x " : "", RDIST, qflag ? " -q" : "");
        if (port < 0) {
                if (debug_port == 0) {
                        if ((retval = (int)init_service(krb5auth_flag)) == 0) {
                                krb5auth_flag = encrypt_flag = 0;
                                (void) init_service(krb5auth_flag);
                        }
                        port = sp->s_port;

                } else {
                        port = debug_port;
                }
        }

        if (debug) {
                printf("port = %d, luser = %s, ruser = %s\n", ntohs(port),
                    user, ruser);
                printf("buf = %s\n", buf);
        }

        fflush(stdout);

        if (krb5auth_flag > 0) {
                if ((encrypt_flag > 0) && (!krb5_privacy_allowed())) {
                        (void) fprintf(stderr, gettext("rdist: Encryption "
                            " not supported.\n"));
                        exit(1);
                }

                authopts = AP_OPTS_MUTUAL_REQUIRED;

                status = kcmd(&rem, &rhost, port, user, ruser,
                    buf, 0, "host", krb_realm, bsd_context, &auth_context,
                    &cred,
                    0,  /* No need for sequence number */
                    0,  /* No need for server seq # */
                    authopts,
                    1,  /* Always set anyport */
                    &kcmd_proto);
                if (status) {
                        /*
                         * If new protocol requested, we dont
                         * fallback to less secure ones.
                         */
                        if (kcmd_proto == KCMD_NEW_PROTOCOL) {
                                (void) fprintf(stderr, gettext("rdist: kcmdv2 "
                                    "to host %s failed - %s\n"
                                    "Fallback to normal rdist denied."),
                                    host, error_message(status));
                                exit(1);
                        }
                        /* check NO_TKT_FILE or equivalent... */
                        if (status != -1) {
                                (void) fprintf(stderr, gettext("rdist: "
                                    "kcmd to host %s failed - %s\n"
                                    "trying normal rdist...\n\n"),
                                    host, error_message(status));
                        } else {
                                (void) fprintf(stderr,
                                    gettext("trying normal rdist...\n"));
                        }
                        /*
                         * kcmd() failed, so we now fallback to normal rdist
                         */
                        krb5auth_flag = encrypt_flag = 0;
                        (void) init_service(krb5auth_flag);
                        port = sp->s_port;
                        goto do_rcmd;
                }
#ifdef DEBUG
                else {
                        (void) fprintf(stderr, gettext("Kerberized rdist "
                            "session, port %d in use "), port);
                        if (kcmd_proto == KCMD_OLD_PROTOCOL)
                                (void) fprintf(stderr,
                                    gettext("[kcmd ver.1].\n"));
                        else
                                (void) fprintf(stderr,
                                    gettext("[kcmd ver.2].\n"));
                }
#endif /* DEBUG */
                session_key = &cred->keyblock;

                if (kcmd_proto == KCMD_NEW_PROTOCOL) {
                        status = krb5_auth_con_getlocalsubkey(bsd_context,
                            auth_context, &session_key);
                        if (status) {
                                com_err("rdist", status,
                                    "determining subkey for session");
                                exit(1);
                        }
                        if (!session_key) {
                                com_err("rdist", 0,
                                    "no subkey negotiated for connection");
                                exit(1);
                        }
                }

                eblock.crypto_entry = session_key->enctype;
                eblock.key = (krb5_keyblock *)session_key;

                init_encrypt(encrypt_flag, bsd_context, kcmd_proto, &desinbuf,
                    &desoutbuf, CLIENT, &eblock);


                if (encrypt_flag > 0) {
                        char *s = gettext("This rdist session is using "
                            "encryption for all data transmissions.\r\n");
                        (void) write(2, s, strlen(s));
                }

        }
        else
do_rcmd:
        {
                rem = rcmd_af(&rhost, port, user, ruser, buf, 0, AF_INET6);
        }

        if (rem < 0)
                return (0);

        cp = buf;
        if (desread(rem, cp, 1, 0) != 1)
                lostconn();
        if (*cp == 'V') {
                do {
                        if (desread(rem, cp, 1, 0) != 1)
                                lostconn();
                } while (*cp++ != '\n' && cp < &buf[RDIST_BUFSIZ]);
                *--cp = '\0';
                cp = buf;
                n = 0;
                while (*cp >= '0' && *cp <= '9')
                        n = (n * 10) + (*cp++ - '0');
                if (*cp == '\0' && n == VERSION)
                        return (1);
                error("connection failed: version numbers don't match"
                    " (local %d, remote %d)\n", VERSION, n);
        } else {
                error("connection failed: version numbers don't match\n");
        }
        closeconn();
        return (0);
}

/*
 * Signal end of previous connection.
 */
static void
closeconn(void)
{
        if (debug)
                printf("closeconn()\n");

        if (rem >= 0) {
                (void) deswrite(rem, "\2\n", 2, 0);
                (void) close(rem);
                rem = -1;
        }
}

void
lostconn(void)
{
        if (iamremote)
                cleanup();
        log(lfp, "rdist: lost connection\n");
        longjmp(env, 1);
}

static int
okname(char *name)
{
        char *cp = name;
        int c;

        do {
                c = *cp;
                if (c & 0200)
                        goto bad;
                if (!isalpha(c) && !isdigit(c) && c != '_' && c != '-')
                        goto bad;
                cp++;
        } while (*cp);
        return (1);
bad:
        error("invalid user name %s\n", name);
        return (0);
}

time_t  lastmod;
FILE    *tfp;
extern  char target[], *tp;

/*
 * Process commands for comparing files to time stamp files.
 */
static void
dodcolon(char **filev, struct namelist *files, char *stamp, struct subcmd *cmds)
{
        struct subcmd *sc;
        struct namelist *f;
        char **cpp;
        struct timeval tv[2];
        struct stat stb;

        if (debug)
                printf("dodcolon()\n");

        if (files == NULL) {
                error("no files to be updated\n");
                return;
        }
        if (stat(stamp, &stb) < 0) {
                error("%s: %s\n", stamp, strerror(errno));
                return;
        }
        if (debug)
                printf("%s: %d\n", stamp, stb.st_mtime);

        subcmds = cmds;
        lastmod = stb.st_mtime;
        if (nflag || (options & VERIFY))
                tfp = NULL;
        else {
                if ((tfp = fopen(Tmpfile, "w")) == NULL) {
                        error("%s: %s\n", stamp, strerror(errno));
                        return;
                }
                (void) gettimeofday(&tv[0], (struct timezone *)NULL);
                tv[1] = tv[0];
                (void) utimes(stamp, tv);
        }

        for (f = files; f != NULL; f = f->n_next) {
                if (filev) {
                        for (cpp = filev; *cpp; cpp++)
                                if (strcmp(f->n_name, *cpp) == 0)
                                        goto found;
                        continue;
                }
        found:
                tp = NULL;
                cmptime(f->n_name);
        }

        if (tfp != NULL)
                (void) fclose(tfp);
        for (sc = cmds; sc != NULL; sc = sc->sc_next)
                if (sc->sc_type == NOTIFY)
                        notify(Tmpfile, NULL, sc->sc_args, lastmod);
        if (!nflag && !(options & VERIFY))
                (void) unlink(Tmpfile);
}

/*
 * Compare the mtime of file to the list of time stamps.
 */
static void
cmptime(char *name)
{
        struct stat stb;

        if (debug)
                printf("cmptime(%s)\n", name);

        if (except(name))
                return;

        if (nflag) {
                printf("comparing dates: %s\n", name);
                return;
        }

        /*
         * first time cmptime() is called?
         */
        if (tp == NULL) {
                if (exptilde(target, RDIST_BUFSIZ, name) == NULL)
                        return;
                tp = name = target;
                while (*tp)
                        tp++;
        }
        if (access(name, 4) < 0 || stat(name, &stb) < 0) {
                error("%s: %s\n", name, strerror(errno));
                return;
        }

        switch (stb.st_mode & S_IFMT) {
        case S_IFREG:
                break;

        case S_IFDIR:
                rcmptime(&stb);
                return;

        default:
                error("%s: not a plain file\n", name);
                return;
        }

        if (stb.st_mtime > lastmod)
                log(tfp, "new: %s\n", name);
}

static void
rcmptime(struct stat *st)
{
        DIR *d;
        struct dirent *dp;
        char *cp;
        char *otp;
        int len;

        if (debug)
                printf("rcmptime(%x)\n", st);

        if ((d = opendir(target)) == NULL) {
                error("%s: %s\n", target, strerror(errno));
                return;
        }
        otp = tp;
        len = tp - target;
        while (dp = readdir(d)) {
                if ((strcmp(dp->d_name, ".") == 0) ||
                    (strcmp(dp->d_name, "..") == 0))
                        continue;
                if (len + 1 + strlen(dp->d_name) >= RDIST_BUFSIZ - 1) {
                        error("%s/%s: Name too long\n", target, dp->d_name);
                        continue;
                }
                tp = otp;
                *tp++ = '/';
                cp = dp->d_name;
                while (*tp++ = *cp++)
                        ;
                tp--;
                cmptime(target);
        }
        closedir(d);
        tp = otp;
        *tp = '\0';
}

/*
 * Notify the list of people the changes that were made.
 * rhost == NULL if we are mailing a list of changes compared to at time
 * stamp file.
 */
static void
notify(char *file, char *rhost, struct namelist *to, time_t lmod)
{
        int fd, len;
        FILE *pf, *popen();
        struct stat stb;

        if ((options & VERIFY) || to == NULL)
                return;
        if (!qflag) {
                printf("notify ");
                if (rhost)
                        printf("@%s ", rhost);
                prnames(to);
        }
        if (nflag)
                return;

        if ((fd = open(file, 0)) < 0) {
                error("%s: %s\n", file, strerror(errno));
                return;
        }
        if (fstat(fd, &stb) < 0) {
                error("%s: %s\n", file, strerror(errno));
                (void) close(fd);
                return;
        }
        if (stb.st_size == 0) {
                (void) close(fd);
                return;
        }
        /*
         * Create a pipe to mailling program.
         */
        pf = popen(MAILCMD, "w");
        if (pf == NULL) {
                error("notify: \"%s\" failed\n", MAILCMD);
                (void) close(fd);
                return;
        }
        /*
         * Output the proper header information.
         */
        fprintf(pf, "From: rdist (Remote distribution program)\n");
        fprintf(pf, "To:");
        if (!any('@', to->n_name) && rhost != NULL)
                fprintf(pf, " %s@%s", to->n_name, rhost);
        else
                fprintf(pf, " %s", to->n_name);
        to = to->n_next;
        while (to != NULL) {
                if (!any('@', to->n_name) && rhost != NULL)
                        fprintf(pf, ", %s@%s", to->n_name, rhost);
                else
                        fprintf(pf, ", %s", to->n_name);
                to = to->n_next;
        }
        putc('\n', pf);
        if (rhost != NULL)
                fprintf(pf, "Subject: files updated by rdist from %s to %s\n",
                    host, rhost);
        else
                fprintf(pf, "Subject: files updated after %s\n", ctime(&lmod));
        putc('\n', pf);

        while ((len = read(fd, buf, RDIST_BUFSIZ)) > 0)
                (void) fwrite(buf, 1, len, pf);
        (void) close(fd);
        (void) pclose(pf);
}

/*
 * Return true if name is in the list.
 */
int
inlist(struct namelist *list, char *file)
{
        struct namelist *nl;

        for (nl = list; nl != NULL; nl = nl->n_next)
                if (strcmp(file, nl->n_name) == 0)
                        return (1);
        return (0);
}

/*
 * Return TRUE if file is in the exception list.
 */
int
except(char *file)
{
        struct  subcmd *sc;
        struct  namelist *nl;

        if (debug)
                printf("except(%s)\n", file);

        for (sc = subcmds; sc != NULL; sc = sc->sc_next) {
                if (sc->sc_type != EXCEPT && sc->sc_type != PATTERN)
                        continue;
                for (nl = sc->sc_args; nl != NULL; nl = nl->n_next) {
                        if (sc->sc_type == EXCEPT) {
                                if (strcmp(file, nl->n_name) == 0)
                                        return (1);
                                continue;
                        }
                        re_comp(nl->n_name);
                        if (re_exec(file) > 0)
                                return (1);
                }
        }
        return (0);
}

char *
colon(char *cp)
{
        while (*cp) {
                if (*cp == ':')
                        return (cp);
                if (*cp == '/')
                        return (0);
                cp++;
        }
        return (0);
}