/*
 * 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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <pthread.h>
#include <unistd.h>
#include <sip.h>
#ifdef  __linux__
#include <sasl/sasl.h>
#include <sasl/saslplug.h>
#else
#include <sys/md5.h>
#endif

#include "sip_miscdefs.h"
#include "sip_msg.h"

void    sip_md5_hash(char *, int, char *, int, char *, int,  char *, int,
            char *, int, char *, int, uchar_t *);

#define SIP_RANDOM_LEN  20

/*
 * Wrapper around /dev/urandom
 */
static int
sip_get_random(char *buf, int buflen)
{
        static int devrandom = -1;

        if (devrandom == -1 &&
            (devrandom = open("/dev/urandom", O_RDONLY)) == -1) {
                return (-1);
        }

        if (read(devrandom, buf, buflen) == -1)
                return (-1);
        return (0);
}

/*
 * Get MD5 hash of call_id, from_tag, to_tag using key
 */
void
sip_md5_hash(char *str1, int lstr1, char *str2, int lstr2, char *str3,
    int lstr3, char *str4, int lstr4, char *str5, int lstr5,
    char *str6, int lstr6, uchar_t *digest)
{
        MD5_CTX ctx;

#ifdef  __linux__
        _sasl_MD5Init(&ctx);

        _sasl_MD5Update(&ctx, (uchar_t *)&sip_hash_salt, sizeof (uint64_t));

        if (str1 != NULL)
                _sasl_MD5Update(&ctx, (uchar_t *)str1, lstr1);

        if (str2 != NULL)
                _sasl_MD5Update(&ctx, (uchar_t *)str2, lstr2);

        if (str3 != NULL)
                _sasl_MD5Update(&ctx, (uchar_t *)str3, lstr3);

        if (str4 != NULL)
                _sasl_MD5Update(&ctx, (uchar_t *)str4, lstr4);

        if (str5 != NULL)
                _sasl_MD5Update(&ctx, (uchar_t *)str5, lstr5);

        if (str6 != NULL)
                _sasl_MD5Update(&ctx, (uchar_t *)str6, lstr6);

        _sasl_MD5Final(digest, &ctx);
#else   /* solaris */
        MD5Init(&ctx);

        MD5Update(&ctx, (uchar_t *)&sip_hash_salt, sizeof (uint64_t));

        if (str1 != NULL)
                MD5Update(&ctx, (uchar_t *)str1, lstr1);

        if (str2 != NULL)
                MD5Update(&ctx, (uchar_t *)str2, lstr2);

        if (str3 != NULL)
                MD5Update(&ctx, (uchar_t *)str3, lstr3);

        if (str4 != NULL)
                MD5Update(&ctx, (uchar_t *)str4, lstr4);

        if (str5 != NULL)
                MD5Update(&ctx, (uchar_t *)str5, lstr5);

        if (str6 != NULL)
                MD5Update(&ctx, (uchar_t *)str6, lstr6);

        MD5Final(digest, &ctx);
#endif
}

/*
 * generate a guid (globally unique id)
 */
char *
sip_guid()
{
        int             i;
        uint8_t         *r;
        uint32_t        random;
        uint32_t        time;
        char            *guid;
        int             guidlen;
#ifdef  __linux__
        struct timespec tspec;
#endif

        guid = (char *)malloc(SIP_RANDOM_LEN + 1);
        if (guid == NULL)
                return (NULL);
        /*
         * Get a 32-bit random #
         */
        if (sip_get_random((char *)&random, sizeof (random)) != 0)
                return (NULL);
#ifdef  __linux__
        if (clock_gettime(CLOCK_REALTIME, &tspec) != 0)
                return (NULL);
        time = (uint32_t)tspec.tv_nsec;
#else
        /*
         * Get 32-bits from gethrtime()
         */
        time = (uint32_t)gethrtime();
#endif
        (void) snprintf(guid, SIP_RANDOM_LEN + 1, "%u%u", random, time);
        guidlen = strlen(guid);

        /*
         * just throw in some alphabets too
         */
        r = (uint8_t *)malloc(guidlen);
        if (sip_get_random((char *)r, guidlen) != 0) {
                free(guid);
                return (NULL);
        }
        for (i = 0; i < guidlen; i++) {
                if ((r[i] >= 65 && r[i] <= 90) ||
                    (r[i] >= 97 && r[i] <= 122)) {
                        guid[i] = r[i];
                }
        }
        free(r);
        return (guid);
}

/*
 * Generate  branchid for a transaction
 */
char *
sip_branchid(sip_msg_t sip_msg)
{
        char            *guid;
        char            *branchid;
        _sip_header_t   *via;
        unsigned char   md5_hash[16];
        _sip_header_t   *to;
        _sip_header_t   *from;
        _sip_header_t   *callid;
        _sip_msg_t      *_sip_msg;
        int             cseq;
        MD5_CTX         ctx;
        size_t          len;
        int             hdrlen;
        int             i;

        if (sip_msg == NULL) {
generate_bid:
                if ((branchid = (char *)malloc(SIP_BRANCHID_LEN + 1)) == NULL)
                        return (NULL);
                guid = sip_guid();
                if (guid == NULL) {
                        free(branchid);
                        return (NULL);
                }
                (void) snprintf(branchid, SIP_BRANCHID_LEN + 1, "z9hG4bK%s",
                    guid);
                free(guid);
                return (branchid);
        }
        _sip_msg = (_sip_msg_t *)sip_msg;
        (void) pthread_mutex_lock(&_sip_msg->sip_msg_mutex);
        via = sip_search_for_header(_sip_msg, SIP_VIA, NULL);
        if (via == NULL) {
                (void) pthread_mutex_unlock(&_sip_msg->sip_msg_mutex);
                goto generate_bid;
        }
        to = sip_search_for_header(_sip_msg, SIP_TO, NULL);
        from = sip_search_for_header(_sip_msg, SIP_FROM, NULL);
        callid = sip_search_for_header(_sip_msg, SIP_CALL_ID, NULL);
        (void) pthread_mutex_unlock(&_sip_msg->sip_msg_mutex);
        cseq = sip_get_callseq_num(_sip_msg, NULL);
        if (to == NULL || from == NULL || callid == NULL || cseq == -1)
                return (NULL);
        if (_sip_msg->sip_msg_req_res == NULL ||
            _sip_msg->sip_msg_req_res->U.sip_request.sip_request_uri.
            sip_str_ptr == NULL) {
                return (NULL);
        }
        len = 2 * sizeof (md5_hash) + 1;
        if ((branchid = malloc(len)) == NULL)
                return (NULL);
#ifdef  __linux__
        _sasl_MD5Init(&ctx);
        hdrlen = via->sip_hdr_end - via->sip_hdr_start;
        _sasl_MD5Update(&ctx, (uchar_t *)via->sip_hdr_start, hdrlen);
        hdrlen = to->sip_hdr_end - to->sip_hdr_start;
        _sasl_MD5Update(&ctx, (uchar_t *)to->sip_hdr_start, hdrlen);
        hdrlen = from->sip_hdr_end - from->sip_hdr_start;
        _sasl_MD5Update(&ctx, (uchar_t *)from->sip_hdr_start, hdrlen);
        hdrlen = callid->sip_hdr_end - callid->sip_hdr_start;
        _sasl_MD5Update(&ctx, (uchar_t *)callid->sip_hdr_start, hdrlen);
        _sasl_MD5Update(&ctx, (uchar_t *)_sip_msg->sip_msg_req_res->
            U.sip_request.sip_request_uri.sip_str_ptr,
            _sip_msg->sip_msg_req_res->U.sip_request.
            sip_request_uri.sip_str_len);
        _sasl_MD5Update(&ctx, (uchar_t *)&cseq, sizeof (int));
        _sasl_MD5Final(md5_hash, &ctx);
#else   /* solaris */
        MD5Init(&ctx);
        hdrlen = via->sip_hdr_end - via->sip_hdr_start;
        MD5Update(&ctx, (uchar_t *)via->sip_hdr_start, hdrlen);
        hdrlen = to->sip_hdr_end - to->sip_hdr_start;
        MD5Update(&ctx, (uchar_t *)to->sip_hdr_start, hdrlen);
        hdrlen = from->sip_hdr_end - from->sip_hdr_start;
        MD5Update(&ctx, (uchar_t *)from->sip_hdr_start, hdrlen);
        hdrlen = callid->sip_hdr_end - callid->sip_hdr_start;
        MD5Update(&ctx, (uchar_t *)callid->sip_hdr_start, hdrlen);
        MD5Update(&ctx, (uchar_t *)_sip_msg->sip_msg_req_res->
            U.sip_request.sip_request_uri.sip_str_ptr,
            _sip_msg->sip_msg_req_res->U.sip_request.
            sip_request_uri.sip_str_len);
        MD5Update(&ctx, (uchar_t *)&cseq, sizeof (int));
        MD5Final(md5_hash, &ctx);
#endif
        for (i = 0; i < sizeof (md5_hash); i++) {
                (void) snprintf(&branchid[2 * i], len - (2 * i), "%02x",
                    md5_hash[i]);
        }
        return (branchid);
}

uint32_t
sip_get_cseq()
{
        time_t  tval;

        tval = time(NULL);

        return ((uint32_t)tval);
}

uint32_t
sip_get_rseq()
{
        time_t  tval;

        tval = time(NULL);

        return ((uint32_t)tval);
}