/*
 * 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 <unistd.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 <pwd.h>
#include <netinet/in.h>
#include <tsol/label.h>
#include <locale.h>
#include "generic.h"

#ifdef C2_DEBUG
#define dprintf(x) { (void) printf x; }
#else
#define dprintf(x)
#endif

#define UNKNOWN_CMD     "???"

static au_event_t       event;
static int              audit_rexd_status = 0;

static char *
build_cmd(char **cmd)
{
        int i, l;
        char *r;

        if (cmd == NULL)
                return (NULL);
        /* count the total length of command line */
        for (i = 0, l = 0; cmd[i] != NULL; i++)
                l += strlen(cmd[i]) + 1;

        if (l == 0)
                return (NULL);
        r = malloc(l);
        if (r != NULL) {
                for (i = 0; cmd[i] != NULL; i++) {
                        (void) strcat(r, cmd[i]);
                        if (cmd[i + 1] != NULL)
                                (void) strcat(r, " ");
                }
        }
        return (r);
}

static int
selected(uid, user, event, sf)
uid_t uid;
char    *user;
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(user, &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));
}

void
audit_rexd_setup()
{
        dprintf(("audit_rexd_setup()\n"));

        event = AUE_rexd;
}

/* ARGSUSED */
static void
audit_rexd_session_setup(char *name, char *mach, uid_t uid)
{
        int                     rc;
        au_mask_t               mask;
        struct auditinfo_addr   info;

        if (getaudit_addr(&info, sizeof (info)) < 0) {
                perror("getaudit_addr");
                exit(1);
        }

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

        mask.am_success = 0;
        mask.am_failure = 0;

        (void) au_user_mask(name, &mask);

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

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

void
audit_rexd_fail(msg, hostname, user, uid, gid, shell, cmd)
        char    *msg;           /* message containing failure information */
        char    *hostname;      /* hostname of machine requesting service */
        char    *user;          /* username of user requesting service */
        uid_t   uid;            /* user id of user requesting service */
        gid_t   gid;            /* group of user requesting service */
        char    *shell;         /* login shell of user requesting service */
        char    **cmd;          /* argv to be executed locally */
{
        int     rd;             /* audit record descriptor */
        char    buf[256];       /* temporary buffer */
        char    *tbuf;          /* temporary buffer */
        int     tlen;
        const char *gtxt;       /* gettext return value */
        pid_t   pid;
        char    *cmdbuf;
        char    *audit_cmd[2] = {NULL, NULL};
        int     dont_free = 0;
        struct auditinfo_addr info;

        dprintf(("audit_rexd_fail()\n"));

        /*
         * check if audit_rexd_fail() or audit_rexd_success()
         * have been called already.
         */
        if (audit_rexd_status == 1) {
                return;
        }

        if (cannot_audit(0)) {
                return;
        }

        /*
         * set status to prevent multiple calls
         * to audit_rexd_fail() and audit_rexd_success()
         */
        audit_rexd_status = 1;

        /* determine if we're preselected */
        if (!selected(uid, user, event, -1))
                return;

        pid = getpid();

        if (getaudit_addr(&info, sizeof (info)) < 0) {
                perror("getaudit_addr");
                exit(1);
        }

        rd = au_open();

        /* add subject token */
        (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());

        /* add reason for failure */
        (void) au_write(rd, au_to_text(msg));

        /* add hostname of machine requesting service */
        (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
                "Remote execution requested by: %s"), hostname);
        (void) au_write(rd, au_to_text(buf));

        /* add username of user requesting service */
        if (user == NULL)
                user = "???";
        (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
            "Username: %s"), user);
        (void) au_write(rd, au_to_text(buf));

        (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
            "User id: %d"), uid);
        (void) au_write(rd, au_to_text(buf));

        if (cmd == NULL) {
                audit_cmd[0] = shell;
                cmd = audit_cmd;
        }

        cmdbuf = build_cmd(cmd);
        if (cmdbuf == NULL) {
                cmdbuf = UNKNOWN_CMD;
                dont_free = 1;
        }

        gtxt = dgettext(bsm_dom, "Command line: %s");
        /* over estimate of size of buffer needed (%s is replaced) */
        tlen = strlen(cmdbuf) + strlen(gtxt) + 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 (!dont_free)
                (void) free(cmdbuf);

        /* add return token */
#ifdef _LP64
        (void) au_write(rd, au_to_return64(-1, (int64_t)0));
#else
        (void) au_write(rd, au_to_return32(-1, (int32_t)0));
#endif

        /* write audit record */
        if (au_close(rd, 1, event) < 0) {
                (void) au_close(rd, 0, 0);
                return;
        }
}

void
audit_rexd_success(hostname, user, uid, gid, shell, cmd)
char    *hostname;      /* hostname of machine requesting service */
char    *user;          /* username of user requesting service, may be NULL */
uid_t   uid;            /* user id of user requesting service */
gid_t   gid;            /* group of user requesting service */
char    *shell;         /* login shell of user requesting service */
char    **cmd;          /* argv to be executed locally, may be NULL */
{
        int     rd;                     /* audit record descriptor */
        char    buf[256];       /* temporary buffer */
        char    *tbuf;          /* temporary buffer */
        int     tlen;
        const char *gtxt;
        pid_t   pid;
        char    *cmdbuf;
        char    *audit_cmd[2] = {NULL, NULL};
        int     dont_free = 0;
        struct auditinfo_addr info;
        char    *empty = "";

        dprintf(("audit_rexd_success()\n"));

        /*
         * check if audit_rexd_fail() or audit_rexd_success()
         * have been called already.
         */
        if (audit_rexd_status == 1) {
                return;
        }

        if (cannot_audit(0)) {
                return;
        }

        /* a little bullet proofing... */

        if (hostname == NULL)
                hostname = empty;
        if (shell == NULL)
                shell = empty;

        /*
         * set status to prevent multiple calls
         * to audit_rexd_fail() and audit_rexd_success()
         */
        audit_rexd_status = 1;

        /* determine if we're preselected */
        if (!selected(uid, user, event, 0))
                goto rexd_audit_session;

        pid = getpid();

        if (getaudit_addr(&info, sizeof (info)) < 0) {
                perror("getaudit_addr");
                exit(1);
        }

        rd = au_open();

        /* add subject token */
        (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());

        /* add hostname of machine requesting service */

        (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
                "Remote execution requested by: %s"), hostname);
        (void) au_write(rd, au_to_text(buf));

        /* add username at machine requesting service */
        (void) snprintf(buf, sizeof (buf), dgettext(bsm_dom,
            "Username: %s"), user);
        (void) au_write(rd, au_to_text(buf));

        if (cmd == NULL) {
                audit_cmd[0] = shell;
                cmd = audit_cmd;
        }

        cmdbuf = build_cmd(cmd);
        if (cmdbuf == NULL) {
                cmdbuf = UNKNOWN_CMD;
                dont_free = 1;
        }

        gtxt = dgettext(bsm_dom, "Command line: %s");
        tlen = strlen(cmdbuf) + strlen(gtxt) + 1;

        if ((tbuf = malloc(tlen)) == NULL) {
                (void) au_close(rd, 0, 0);
                goto rexd_audit_session;
        }

        (void) snprintf(tbuf, tlen, gtxt, cmdbuf);
        (void) au_write(rd, au_to_text(tbuf));
        (void) free(tbuf);
        if (!dont_free)
                (void) free(cmdbuf);

        /* add return token */
#ifdef _LP64
        (void) au_write(rd, au_to_return64(0, (int64_t)0));
#else
        (void) au_write(rd, au_to_return32(0, (int32_t)0));
#endif

        /* write audit record */
        if (au_close(rd, 1, event) < 0) {
                (void) au_close(rd, 0, 0);
        }

rexd_audit_session:
        audit_rexd_session_setup(user, hostname, uid);
}