/*
 * 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 2001 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright (c) 2016 by Delphix. All rights reserved.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * mailx -- a modified version of a University of California at Berkeley
 *      mail program
 *
 * Handle name lists.
 */

#include "rcv.h"
#include <locale.h>

static struct name      *nalloc(char str[]);
static int              isfileaddr(char *name);
static int              lengthof(struct name *name);
static struct name      *gexpand(struct name *nlist, struct grouphead *gh,
    int metoo, int arg_ntype);
static char             *norm(register char *user, register char *ubuf,
    int nbangs);
static struct name      *put(struct name *list, struct name *node);

/*
 * Allocate a single element of a name list,
 * initialize its name field to the passed
 * name and return it.
 */

static struct name *
nalloc(char str[])
{
        register struct name *np;

        np = (struct name *)salloc(sizeof (*np));
        np->n_flink = NIL;
        np->n_blink = NIL;
        np->n_type = -1;
        np->n_full = savestr(str);
        np->n_name = skin(np->n_full);
        return (np);
}

/*
 * Find the tail of a list and return it.
 */

struct name *
tailof(struct name *name)
{
        register struct name *np;

        np = name;
        if (np == NIL)
                return (NIL);
        while (np->n_flink != NIL)
                np = np->n_flink;
        return (np);
}

/*
 * Extract a list of names from a line,
 * and make a list of names from it.
 * Return the list or NIL if none found.
 */

struct name *
extract(char line[], int arg_ntype)
{
        short ntype = (short)arg_ntype;
        register char *cp;
        register struct name *top, *np, *t;
        char nbuf[BUFSIZ], abuf[BUFSIZ];
        int comma;

        if (line == NOSTR || strlen(line) == 0)
                return (NIL);
        comma = docomma(line);
        top = NIL;
        np = NIL;
        cp = line;
        while ((cp = yankword(cp, nbuf, sizeof (nbuf), comma)) != NOSTR) {
                if (np != NIL && equal(nbuf, "at")) {
                        nstrcpy(abuf, sizeof (abuf), nbuf);
                        if ((cp = yankword(cp, nbuf, sizeof (nbuf),
                            comma)) == NOSTR) {
                                nstrcpy(nbuf, sizeof (nbuf), abuf);
                                goto normal;
                        }
                        snprintf(abuf, sizeof (abuf), "%s@%s", np->n_name,
                            nbuf);
                        np->n_name = savestr(abuf);
                        continue;
                }
normal:
                t = nalloc(nbuf);
                t->n_type = ntype;
                if (top == NIL)
                        top = t;
                else
                        np->n_flink = t;
                t->n_blink = np;
                np = t;
        }
        return (top);
}

/*
 * Turn a list of names into a string of the same names.
 */

char *
detract(register struct name *np, int ntype)
{
        register int s;
        register char *cp, *top;
        register struct name *p;

        if (np == NIL)
                return (NOSTR);
        s = 0;
        for (p = np; p != NIL; p = p->n_flink) {
                if ((ntype && (p->n_type & GMASK) != ntype) ||
                    (p->n_type & GDEL))
                        continue;
                s += strlen(p->n_full) + 2;
        }
        if (s == 0)
                return (NOSTR);
        top = (char *)salloc((unsigned)(++s));
        cp = top;
        for (p = np; p != NIL; p = p->n_flink) {
                if ((ntype && (p->n_type & GMASK) != ntype) ||
                    (p->n_type & GDEL))
                        continue;
                cp = copy(p->n_full, cp);
                *cp++ = ',';
                *cp++ = ' ';
        }
        *cp = 0;
        return (top);
}

struct name *
outpre(struct name *to)
{
        register struct name *np;

        for (np = to; np; np = np->n_flink)
                if (isfileaddr(np->n_name))
                        np->n_type |= GDEL;
        return (to);
}

/*
 * For each recipient in the passed name list with a /
 * in the name, append the message to the end of the named file
 * and remove them from the recipient list.
 *
 * Recipients whose name begins with | are piped through the given
 * program and removed.
 */

int
outof(struct name *names, FILE *fo)
{
        register int c;
        register struct name *np;
        time_t now;
        char *date, *fname, *shell;
        FILE *fout, *fin;
        int ispipe;
        int nout = 0;
        int fd = 0;
#ifdef preSVr4
        char line[BUFSIZ];
#endif

        if (value("expandaddr") == NOSTR)
                return (nout);

        for (np = names; np != NIL; np = np->n_flink) {
                if (!isfileaddr(np->n_name) && np->n_name[0] != '|')
                        continue;
                nout++;
                ispipe = np->n_name[0] == '|';
                if (ispipe)
                        fname = np->n_name+1;
                else
                        fname = safeexpand(np->n_name);

                /*
                 * See if we have copied the complete message out yet.
                 * If not, do so.
                 */

                if (image < 0) {
                        fd = open(tempEdit, O_CREAT|O_EXCL|O_APPEND|O_WRONLY,
                            0600);
                        if ((fd  < 0) && (errno == EEXIST)) {
                                if ((fd = open(tempEdit, O_APPEND|O_WRONLY,
                                    0600)) < 0) {
                                        perror(tempEdit);
                                        senderr++;
                                        goto cant;
                                }
                        }
                        if ((fout = fdopen(fd, "a")) == NULL) {
                                perror(tempEdit);
                                senderr++;
                                goto cant;
                        }
                        image = open(tempEdit, O_RDWR);
                        unlink(tempEdit);
                        if (image < 0) {
                                perror(tempEdit);
                                senderr++;
                                goto cant;
                        } else {
                                rewind(fo);
                                time(&now);
                                date = ctime(&now);
                                fprintf(fout, "From %s %s", myname, date);
                                while ((c = getc(fo)) != EOF)
                                        putc(c, fout);
                                rewind(fo);
                                fflush(fout);
                                if (fferror(fout))
                                        perror(tempEdit);
                                fclose(fout);
                        }
                }

                /*
                 * Now either copy "image" to the desired file
                 * or give it as the standard input to the desired
                 * program as appropriate.
                 */

                if (ispipe) {
                        wait((int *)NULL);
                        switch (fork()) {
                        case 0:
                                sigchild();
                                sigset(SIGHUP, SIG_IGN);
                                sigset(SIGINT, SIG_IGN);
                                sigset(SIGQUIT, SIG_IGN);
                                close(0);
                                dup(image);
                                close(image);
                                lseek(0, 0L, 0);
                                if ((shell = value("SHELL")) == NOSTR ||
                                    *shell == '\0')
                                        shell = SHELL;
                                (void) execlp(shell, shell, "-c", fname,
                                    (char *)0);
                                perror(shell);
                                exit(1);
                                break;

                        case (pid_t)-1:
                                perror("fork");
                                senderr++;
                                goto cant;
                        }
                } else {
                        if ((fout = fopen(fname, "a")) == NULL) {
                                perror(fname);
                                senderr++;
                                goto cant;
                        }
                        fin = Fdopen(image, "r");
                        if (fin == NULL) {
                                fprintf(stderr,
                                    gettext("Can't reopen image\n"));
                                fclose(fout);
                                senderr++;
                                goto cant;
                        }
                        rewind(fin);
#ifdef preSVr4
                        putc(getc(fin), fout);
                        while (fgets(line, sizeof (line), fin)) {
                                if (strncmp(line, "From ", 5) == 0)
                                        putc('>', fout);
                                fputs(line, fout);
                        }
#else
                        while ((c = getc(fin)) != EOF)
                                putc(c, fout);
#endif
                        putc('\n', fout);
                        fflush(fout);
                        if (fferror(fout))
                                senderr++, perror(fname);
                        fclose(fout);
                        fclose(fin);
                }
cant:
                /*
                 * In days of old we removed the entry from the
                 * the list; now for sake of header expansion
                 * we leave it in and mark it as deleted.
                 */

#ifdef CRAZYWOW
                {
                register struct name *t, *x;

                if (np == top) {
                        top = np->n_flink;
                        if (top != NIL)
                                top->n_blink = NIL;
                        np = top;
                        continue;
                }
                x = np->n_blink;
                t = np->n_flink;
                x->n_flink = t;
                if (t != NIL)
                        t->n_blink = x;
                np = t;
                }
#endif

                np->n_type |= GDEL;
        }
        if (image >= 0) {
                close(image);
                image = -1;
        }
        return (nout);
}

/*
 * Determine if the passed address is a local "send to file" address.
 * If any of the network metacharacters precedes any slashes, it can't
 * be a filename.  We cheat with .'s to allow path names like ./...
 * If "fcc" has been unset, then short-circuit those tests, but not
 * the +... test.
 */
static int
isfileaddr(char *name)
{
        register char *cp;
        char *fcc = value("fcc");

        if (any('@', name))
                return (0);
        if (*name == '+')
                return (1);
        if (fcc == NOSTR)
                return (0);
        for (cp = name; *cp; cp++) {
                if (*cp == '.')
                        continue;
                if (any(*cp, metanet))
                        return (0);
                if (*cp == '/')
                        return (1);
        }
        return (0);
}

/*
 * Map all of the aliased users in the invoker's mailrc
 * file and insert them into the list.
 * Changed after all these months of service to recursively
 * expand names (2/14/80).
 */

struct name *
usermap(struct name *names)
{
        register struct name *newnames, *np, *cp;
        struct grouphead *gh;
        register int metoo;

        newnames = NIL;
        np = names;
        metoo = (value("metoo") != NOSTR);
        while (np != NIL) {
                if (np->n_name[0] == '\\') {
                        cp = np->n_flink;
                        newnames = put(newnames, np);
                        np = cp;
                        continue;
                }
                gh = findgroup(np->n_name);
                cp = np->n_flink;
                if (gh != NOGRP)
                        newnames = gexpand(newnames, gh, metoo, np->n_type);
                else
                        newnames = put(newnames, np);
                np = cp;
        }
        return (newnames);
}

/*
 * Recursively expand a group name.  We limit the expansion to some
 * fixed level to keep things from going haywire.
 * Direct recursion is not expanded for convenience.
 */

static struct name *
gexpand(struct name *nlist, struct grouphead *gh, int metoo, int arg_ntype)
{
        short ntype = (short)arg_ntype;
        struct mgroup *gp;
        struct grouphead *ngh;
        struct name *np;
        static int depth;
        register char *cp;

        if (depth > MAXEXP) {
                printf(gettext("Expanding alias to depth larger than %d\n"),
                    MAXEXP);
                return (nlist);
        }
        depth++;
        for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link) {
                cp = gp->ge_name;
                if (*cp == '\\')
                        goto quote;
                if (strcmp(cp, gh->g_name) == 0)
                        goto quote;
                if ((ngh = findgroup(cp)) != NOGRP) {
                        nlist = gexpand(nlist, ngh, metoo, ntype);
                        continue;
                }
quote:
                np = nalloc(cp);
                np->n_type = ntype;
                /*
                 * At this point should allow to expand
                 * to self if only person in group
                 */
                if (gp == gh->g_list && gp->ge_link == NOGE)
                        goto skip;
                if (!metoo && samebody(myname, gp->ge_name, FALSE))
                        np->n_type |= GDEL;
skip:
                nlist = put(nlist, np);
        }
        depth--;
        return (nlist);
}

/*
 * Normalize a network name for comparison purposes.
 */
static char *
norm(register char *user, register char *ubuf, int nbangs)
{
        register char *cp;
        int inubuf = 0;

        while (*user++ == '!')
                ;
        user--;
        if (!strchr(user, '!')) {
                snprintf(ubuf, BUFSIZ, "%s!%s", host, user);
                user = ubuf;
                inubuf++;
        }
        if (nbangs) {
                cp = user + strlen(user);
                while (nbangs--)
                        while (cp > user && *--cp != '!')
                                ;
                user = (cp > user) ? ++cp : cp;
                /*
                 * Now strip off all Internet-type
                 * hosts.
                 */
                if ((cp = strchr(user, '%')) == NOSTR)
                        cp = strchr(user, '@');
                if (cp != NOSTR) {
                        if (!inubuf) {
                                strncpy(ubuf, user, cp - user);
                                ubuf[cp - user] = '\0';
                                user = ubuf;
                        } else
                                *cp = '\0';
                }
        }
        return (user);
}

/*
 * Implement allnet options.
 */
int
samebody(register char *user, register char *addr, int fuzzy)
{
        char ubuf[BUFSIZ], abuf[BUFSIZ];
        char *allnet = value("allnet");
        int nbangs = allnet ? (strcmp(allnet, "uucp") == 0) ? 2 : 1 : 0;

        if (fuzzy && value("fuzzymatch")) {
                int i;

                (void) strlcpy(ubuf, user, BUFSIZ);
                for (i = 0; ubuf[i]; i++)
                        ubuf[i] = tolower(ubuf[i]);
                (void) strlcpy(abuf, addr, BUFSIZ);
                for (i = 0; abuf[i]; i++)
                        abuf[i] = tolower(abuf[i]);
                return (strstr(abuf, ubuf) != NOSTR);
        }
        user = norm(user, ubuf, nbangs);
        addr = norm(addr, abuf, nbangs);
        return (strcmp(user, addr) == 0);
}

/*
 * Compute the length of the passed name list and
 * return it.
 */
static int
lengthof(struct name *name)
{
        register struct name *np;
        register int c;

        for (c = 0, np = name; np != NIL; c++, np = np->n_flink)
                ;
        return (c);
}

/*
 * Concatenate the two passed name lists, return the result.
 */

struct name *
cat(struct name *n1, struct name *n2)
{
        register struct name *tail;

        if (n1 == NIL)
                return (n2);
        if (n2 == NIL)
                return (n1);
        tail = tailof(n1);
        tail->n_flink = n2;
        n2->n_blink = tail;
        return (n1);
}

/*
 * Unpack the name list onto a vector of strings.
 * Return an error if the name list won't fit.
 */

char **
unpack(struct name *np)
{
        register char **ap, **top;
        register struct name *n;
        char hbuf[10];
        int t, extra, metoo, verbose;

        n = np;
        if ((t = lengthof(n)) == 0)
                panic("No names to unpack");

        /*
         * Compute the number of extra arguments we will need.  We need at least
         * 3 extra -- one for "mail", one for a terminating -- to stop sendmail
         * option processing, and one for the terminating 0 pointer.
         *
         * Additional spots may be needed to pass along -r and -f to the host
         * mailer.
         */

        extra = 3;

        if (rflag != NOSTR)
                extra += 2;
        extra++;
        metoo = value("metoo") != NOSTR;
        if (metoo)
                extra++;
        verbose = value("verbose") != NOSTR;
        if (verbose)
                extra++;
        if (hflag)
                extra += 2;
        top = (char **)salloc((t + extra) * sizeof (char *));
        ap = top;
        *ap++ = "sendmail";
        if (rflag != NOSTR) {
                *ap++ = "-r";
                *ap++ = rflag;
        }
        *ap++ = "-i";
        if (metoo)
                *ap++ = "-m";
        if (verbose)
                *ap++ = "-v";
        if (hflag) {
                *ap++ = "-h";
                snprintf(hbuf, sizeof (hbuf), "%d", hflag);
                *ap++ = savestr(hbuf);
        }
        *ap++ = "--";
        while (n != NIL) {
                if (n->n_type & GDEL) {
                        n = n->n_flink;
                        continue;
                }
                *ap++ = n->n_name;
                n = n->n_flink;
        }
        *ap = NOSTR;
        return (top);
}

/*
 * See if the user named themself as a destination
 * for outgoing mail. If so, set the global flag
 * selfsent so that we avoid removing their mailbox.
 */

void
mechk(struct name *names)
{
        register struct name *np;

        for (np = names; np != NIL; np = np->n_flink)
                if ((np->n_type & GDEL) == 0 &&
                    samebody(np->n_name, myname, FALSE)) {
                        selfsent++;
                        return;
                }
}

/*
 * Remove all of the duplicates from the passed name list by
 * insertion sorting them, then checking for dups.
 * Return the head of the new list.
 */

struct name *
elide(struct name *names)
{
        register struct name *np, *t, *newnames;
        struct name *x;

        if (names == NIL)
                return (NIL);
        newnames = names;
        np = names;
        np = np->n_flink;
        if (np != NIL)
                np->n_blink = NIL;
        newnames->n_flink = NIL;
        while (np != NIL) {
                t = newnames;
                while (strcmp(t->n_name, np->n_name) < 0) {
                        if (t->n_flink == NIL)
                                break;
                        t = t->n_flink;
                }

                /*
                 * If we ran out of t's, put the new entry after
                 * the current value of t.
                 */

                if (strcmp(t->n_name, np->n_name) < 0) {
                        t->n_flink = np;
                        np->n_blink = t;
                        t = np;
                        np = np->n_flink;
                        t->n_flink = NIL;
                        continue;
                }

                /*
                 * Otherwise, put the new entry in front of the
                 * current t.  If at the front of the list,
                 * the new guy becomes the new head of the list.
                 */

                if (t == newnames) {
                        t = np;
                        np = np->n_flink;
                        t->n_flink = newnames;
                        newnames->n_blink = t;
                        t->n_blink = NIL;
                        newnames = t;
                        continue;
                }

                /*
                 * The normal case -- we are inserting into the
                 * middle of the list.
                 */

                x = np;
                np = np->n_flink;
                x->n_flink = t;
                x->n_blink = t->n_blink;
                t->n_blink->n_flink = x;
                t->n_blink = x;
        }

        /*
         * Now the list headed up by new is sorted.
         * Go through it and remove duplicates.
         * Remember the best "type" among all the
         * duplicates of a name.
         */

        np = newnames;
        while (np != NIL) {
                int type;

                t = np;
                type = np->n_type;
                while (t->n_flink != NIL &&
                    strcmp(np->n_name, t->n_flink->n_name) == 0) {
                        t = t->n_flink;
                        /* "To" before "Cc" before "Bcc" */
                        if (t->n_type < type)
                                type = t->n_type;
                }
                if (t == np || t == NIL) {
                        np = np->n_flink;
                        continue;
                }

                /*
                 * Now t points to the last entry with the same name
                 * as np.  Make np point beyond t.
                 */

                np->n_flink = t->n_flink;
                if (t->n_flink != NIL)
                        t->n_flink->n_blink = np;
                np->n_type = type;
                np = np->n_flink;
        }
        return (newnames);
}

/*
 * Put another node onto a list of names and return
 * the list.
 */

static struct name *
put(struct name *list, struct name *node)
{
        node->n_flink = list;
        node->n_blink = NIL;
        if (list != NIL)
                list->n_blink = node;
        return (node);
}


/*
 * Delete the given name from a namelist.
 */
struct name *
delname(register struct name *np, char name[])
{
        register struct name *p;

        for (p = np; p != NIL; p = p->n_flink)
                if (samebody(name, p->n_name, FALSE)) {
                        if (p->n_blink == NIL) {
                                if (p->n_flink != NIL)
                                        p->n_flink->n_blink = NIL;
                                np = p->n_flink;
                                continue;
                        }
                        if (p->n_flink == NIL) {
                                if (p->n_blink != NIL)
                                        p->n_blink->n_flink = NIL;
                                continue;
                        }
                        p->n_blink->n_flink = p->n_flink;
                        p->n_flink->n_blink = p->n_blink;
                }
        return (np);
}

/*
 * Call the given routine on each element of the name
 * list, replacing said value if need be.
 */

void
mapf(register struct name *np, char *from)
{
        register struct name *p;

        if (debug) fprintf(stderr, "mapf %lx, %s\n", (long)np, from);
        for (p = np; p != NIL; p = p->n_flink)
                if ((p->n_type & GDEL) == 0) {
                        p->n_name = netmap(p->n_name, from);
                        p->n_full = splice(p->n_name, p->n_full);
                }
        if (debug) fprintf(stderr, "mapf %s done\n", from);
}