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


/*
 * mkmap - program to convert the mail.aliases map into an
 * inverse map of <user@host> back to <preferred-alias>
 */

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <ndbm.h>
#include <stdio.h>
#include <ctype.h>
#include <netdb.h>
#include <sys/systeminfo.h>

#include "ypdefs.h"
USE_YP_PREFIX
USE_YP_MASTER_NAME
USE_YP_LAST_MODIFIED

#define MKAL_INCLUDE ":include:"

void CopyName(char *dst, char *src, int len);
int HostCheck(char *h, char *a);
void DoName(char *cp);
void UpperCase(char *cp);
void AddYPEntries(void);

int Verbose = 0;        /* to get the gory details */
int UucpOK = 0;         /* pass all UUCP names right through */
int DomainOK = 0;       /* pass all Domain names (with dots) */
int ErrorCheck = 0;     /* check carefully for errors */
int NoOutput = 0;       /* no output, just do the check */
int Simple = 0;         /* Do not do the user name preference step */
int NameMode = 0;       /* Try to capitalize as names */

DBM *Indbm = NULL, *Scandbm = NULL, *Outdbm = NULL;

int
IsMailingList(char *s)
{
        /*
         * returns true if the given string is a mailing list
         */
        char *p;

        if (strchr(s, ','))
                return (1);
        if (strchr(s, '|'))
                return (1);
        p = strchr(s, ':');
        if (p && strncmp(p, MKAL_INCLUDE, sizeof (MKAL_INCLUDE)))
                return (1);
        return (0);
}

int
IsQualified(char *s, char *p, char *h)
{
        /*
         * returns true if the given string is qualified with a host name
         */
        register char *middle;

        middle = strchr(s, '@');
        if (middle) {
                for (middle = s; *middle != '@'; *p++ = *middle++)
                        continue;
                *p = '\0';
                CopyName(h, middle+1, strlen(middle + 1));
                return (1);
        }
        middle = strrchr(s, '!');
        if (middle) {
                strcpy(p, middle+1);
                *middle = '\0';
                CopyName(h, s, strlen(s));
                *middle = '!';
                return (1);
        }
        return (0);
}

int
IsMaint(char *s)
{
        /*
         * returns true if the given string is one of the maintenence
         * strings used in sendmail or NIS.
         */
        if (*s == '@')
                return (1);
        if (strncmp(s, yp_prefix, yp_prefix_sz) == 0)
                return (1);
        return (0);
}

void
CopyName(char *dst, char *src, int len)
{
        /*
         * copy a string, but ignore white space
         */
        while (*src && len--) {
                if (isspace(*src))
                        src++;
                else
                        *dst++ = *src++;
        }
        *dst = '\0';
}

int
Compare(char *s1, char *s2)
{
        /*
         * compare strings, but ignore white space
         */
        while (*s1 != '\0' && isspace(*s1))
                s1++;
        while (*s2 != '\0' && isspace(*s2))
                s2++;
        return (strcmp(s1, s2));
}

void
ProcessMap(void)
{
        datum key, value, part, partvalue;
        char address[PBLKSIZ];  /* qualified version */
        char user[PBLKSIZ];             /* unqualified version */
        char userpart[PBLKSIZ]; /* unqualified part of qualified addr. */
        char hostpart[PBLKSIZ]; /* rest of qualified addr. */

        for (key = dbm_firstkey(Scandbm); key.dptr != NULL;
                                                key = dbm_nextkey(Scandbm)) {
                value = dbm_fetch(Indbm, key);
                CopyName(address, value.dptr, value.dsize);
                CopyName(user, key.dptr, key.dsize);
                if (address == NULL) continue;
                if (IsMailingList(address)) continue;
                if (!IsQualified(address, userpart, hostpart)) continue;
                if (IsMaint(user)) continue;
                if (ErrorCheck && HostCheck(hostpart, address)) {
                        printf("Invalid host %s in %s:%s\n",
                                hostpart, user, address);
                        continue;
                }
                part.dptr = userpart;
                part.dsize = strlen(userpart) + 1;
                if (Simple)
                        partvalue.dptr = NULL;
                else
                        partvalue = dbm_fetch(Indbm, part);
                value.dptr = address;
                value.dsize = strlen(address) + 1;
                if (partvalue.dptr != NULL &&
                        Compare(partvalue.dptr, user) == 0) {

                        if (NameMode)
                                DoName(userpart);
                        if (!NoOutput)
                                dbm_store(Outdbm, value, part, DBM_REPLACE);
                        if (Verbose) printf("%s --> %s --> %s\n",
                                                userpart, user, address);
                } else {
                        if (NameMode)
                                DoName(user);
                        key.dptr = user;
                        key.dsize = strlen(user) + 1;
                        if (!NoOutput)
                                dbm_store(Outdbm, value, key, DBM_REPLACE);
                        if (Verbose)
                                printf("%s --> %s\n", user, address);
                }
        }
}


/*
 * Returns true if this is an invalid host
 */
int
HostCheck(char *h, char *a)
{
        struct hostent *hp;

        if (DomainOK && strchr(a, '.'))
                return (0);

        if (UucpOK && strchr(a, '!'))
                return (0);

        hp = gethostbyname(h);
        return (hp == NULL);
}

/*
 * Apply some Heurisitcs to upper case-ify the name
 * If it has a dot in it.
 */
void
DoName(char *cp)
{
        if (strchr(cp, '.') == NULL)
                return;

        while (*cp) {
                UpperCase(cp);
                while (*cp && *cp != '-' && *cp != '.')
                        cp++;
                if (*cp)
                        cp++;   /* skip past punctuation */
        }
}

/*
 * upper cases one name - stops at a .
 */
void
UpperCase(char *cp)
{
        int ch = cp[0];

        if (isupper(ch))
                ch = tolower(ch);

        if (ch == 'f' && cp[1] == 'f')
                return; /* handle ff */

        if (ch == 'm' && cp[1] == 'c' && islower(cp[2]))
                cp[2] = toupper(cp[2]);
        if (islower(ch))
                cp[0] = toupper(ch);
}

void
AddYPEntries(void)
{
        datum key, value;
        char last_modified[PBLKSIZ];
        char host_name[PBLKSIZ];
        time_t now;

        /*
         * Add the special NIS entries.
         */
        key.dptr = yp_last_modified;
        key.dsize = yp_last_modified_sz;
        time(&now);
        sprintf(last_modified, "%10.10d", now);
        value.dptr = last_modified;
        value.dsize = strlen(value.dptr);
        dbm_store(Outdbm, key, value, DBM_REPLACE);

        key.dptr = yp_master_name;
        key.dsize = yp_master_name_sz;
        sysinfo(SI_HOSTNAME, host_name, sizeof (host_name));
        value.dptr = host_name;
        value.dsize = strlen(value.dptr);
        dbm_store(Outdbm, key, value, DBM_REPLACE);
}

int
main(int argc, char *argv[])
{
        while (argc > 1 && argv[1][0] == '-') {
        switch (argv[1][1]) {
                case 'v':
                        Verbose = 1;
                        break;

                case 'u':
                        UucpOK = 1;
                        break;

                case 'd':
                        DomainOK = 1;
                        break;

                case 'e':
                        ErrorCheck = 1;
                        break;

                case 's':
                        Simple = 1;
                        break;

                case 'n':
                        NameMode = 1;
                        break;

                default:
                        printf("Unknown option %c\n", argv[1][1]);
                        break;
                }
                argc--; argv++;
        }
        if (argc < 2) {
printf("Usage: mkalias [-e] [-v] [-u] [-d] [-s] [-n] <input> <output>\n");
                exit(1);
        }
        Indbm = dbm_open(argv[1], O_RDONLY, 0);
        if (Indbm == NULL) {
                printf("Unable to open input database %s\n", argv[1]);
                exit(1);
        }
        Scandbm = dbm_open(argv[1], O_RDONLY, 0);
        if (Scandbm == NULL) {
                printf("Unable to open input database %s\n", argv[1]);
                exit(1);
        }
        if (argv[2] == NULL)
                NoOutput = 1;
        else {
                Outdbm = dbm_open(argv[2], O_RDWR|O_CREAT|O_TRUNC, 0644);
                if (Outdbm == NULL) {
                        printf("Unable to open output database %s\n", argv[2]);
                        exit(1);
                }
        }
        ProcessMap();
        dbm_close(Indbm);
        dbm_close(Scandbm);
        if (!NoOutput) {
                AddYPEntries();
                dbm_close(Outdbm);
        }
        return (0);
}