/*
 * 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 (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <stdio.h>
#include <sys/fcntl.h>
#include <bsm/audit.h>
#include <bsm/audit_record.h>
#include <bsm/audit_uevents.h>
#include <bsm/libbsm.h>
#include <bsm/audit_private.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <netinet/in.h>
#include <tsol/label.h>
#include <locale.h>
#include <unistd.h>
#include <generic.h>

static au_event_t       rshd_event;     /* audit event number */
static uint32_t         rshd_addr[4];   /* peer address */

static void generate_record(char *, char *, char *, int, char *);
static void setup_session(char *);
static int selected(uid_t, char *, au_event_t, int);

int
audit_rshd_setup()
{
        rshd_event = AUE_rshd;
        return (0);
}

/* ARGSUSED */
int
audit_rshd_fail(msg, hostname, remuser, locuser, cmdbuf)
char    *msg;           /* message containing failure information */
char    *hostname;              /* hostname of machine requesting service */
char    *remuser;               /* username at machine requesting service */
char    *locuser;               /* username of local machine */
char    *cmdbuf;                /* command line to be executed locally */
{
        if (cannot_audit(0)) {
                return (0);
        }
        generate_record(remuser, locuser, cmdbuf, -1, msg);
        return (0);
}

/* ARGSUSED */
int
audit_rshd_success(hostname, remuser, locuser, cmdbuf)
char    *hostname;              /* hostname of machine requesting service */
char    *remuser;               /* username at machine requesting service */
char    *locuser;               /* username at local machine */
char    *cmdbuf;                /* command line to be executed locally */
{
        if (cannot_audit(0)) {
                return (0);
        }
        generate_record(remuser, locuser, cmdbuf, 0, "");
        setup_session(locuser);
        return (0);
}


#include <pwd.h>

static void
generate_record(char *remuser,  /* username at machine requesting service */
                char *locuser,  /* username of local machine */
                char *cmdbuf,   /* command line to be executed locally */
                int sf_flag,    /* success (0) or failure (-1) flag */
                char *msg)      /* message containing failure information */
{
        int     rd;             /* audit record descriptor */
        char    buf[256];       /* temporary buffer */
        char    *tbuf;          /* temporary buffer */
        int     tlen;
        const char *gtxt;
        uid_t   uid;
        gid_t   gid;
        pid_t   pid;
        struct passwd *pwd;
        struct auditinfo_addr info;

        if (cannot_audit(0)) {
                return;
        }

        pwd = getpwnam(locuser);
        if (pwd == NULL) {
                uid = (uid_t)-1;
                gid = (gid_t)-1;
        } else {
                uid = pwd->pw_uid;
                gid = pwd->pw_gid;
        }

        if (!selected(uid, locuser, rshd_event, sf_flag))
                return;

        pid = getpid();

        /* see if terminal id already set */
        if (getaudit_addr(&info, sizeof (info)) < 0) {
                perror("getaudit");
        }
        rd = au_open();

        (void) au_write(rd, au_to_subject_ex(uid, uid, gid, uid, gid, pid, pid,
            &info.ai_termid));
        if (is_system_labeled())
                (void) au_write(rd, au_to_mylabel());

        gtxt = dgettext(bsm_dom, "cmd %s");
        tlen = strlen(gtxt) + strlen(cmdbuf) + 1;
        if ((tbuf = malloc(tlen)) == NULL) {
                (void) au_close(rd, 0, 0);
                return;
        }
        (void) snprintf(tbuf, tlen, gtxt, cmdbuf);
        (void) au_write(rd, au_to_text(tbuf));
        (void) free(tbuf);

        if (strcmp(remuser, locuser) != 0) {
                (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
                    "remote user %s"), remuser);
                (void) au_write(rd, au_to_text(buf));
        }

        if (sf_flag == -1) {
                (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
                    "local user %s"), locuser);
                (void) au_write(rd, au_to_text(buf));
                (void) au_write(rd, au_to_text(msg));
        }

#ifdef _LP64
        (void) au_write(rd, au_to_return64(sf_flag, (int64_t)0));
#else
        (void) au_write(rd, au_to_return32(sf_flag, (int32_t)0));
#endif

        if (au_close(rd, 1, rshd_event) < 0) {
                (void) au_close(rd, 0, 0);
        }
}

static int
selected(uid_t uid, char *locuser, au_event_t event, int sf)
{
        int             sorf;
        struct au_mask  mask;

        mask.am_success = mask.am_failure = 0;
        if (uid > MAXEPHUID) {
                /* get non-attrib flags */
                (void) auditon(A_GETKMASK, (caddr_t)&mask, sizeof (mask));
        } else {
                (void) au_user_mask(locuser, &mask);
        }

        if (sf == 0) {
                sorf = AU_PRS_SUCCESS;
        } else if (sf == -1) {
                sorf = AU_PRS_FAILURE;
        } else {
                sorf = AU_PRS_BOTH;
        }

        return (au_preselect(event, &mask, sorf, AU_PRS_REREAD));
}

static void
setup_session(char *locuser)
{
        int     rc;
        struct auditinfo_addr info;
        au_mask_t               mask;
        uid_t                   uid;
        struct passwd *pwd;

        pwd = getpwnam(locuser);
        if (pwd == NULL)
                uid = (uid_t)-1;
        else
                uid = pwd->pw_uid;

        /* see if terminal id already set */
        if (getaudit_addr(&info, sizeof (info)) < 0) {
                perror("getaudit");
        }

        info.ai_auid = uid;
        info.ai_asid = getpid();

        mask.am_success = 0;
        mask.am_failure = 0;
        (void) au_user_mask(locuser, &mask);

        info.ai_mask.am_success = mask.am_success;
        info.ai_mask.am_failure = mask.am_failure;

        rshd_addr[0] = info.ai_termid.at_addr[0];
        rshd_addr[1] = info.ai_termid.at_addr[1];
        rshd_addr[2] = info.ai_termid.at_addr[2];
        rshd_addr[3] = info.ai_termid.at_addr[3];

        rc = setaudit_addr(&info, sizeof (info));
        if (rc < 0) {
                perror("setaudit");
        }
}