/*
 * Copyright (c) 2006 Chad Mynhier.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "config.h"
#include "includes.h"

#include <sys/types.h>
#include <sys/stat.h>

#include <errno.h>
#ifdef HAVE_FCNTL_H
# include <fcntl.h>
#endif
#include <stdarg.h>
#include <string.h>
#include <unistd.h>

#include "log.h"

#ifdef USE_SOLARIS_PROCESS_CONTRACTS

#include <libcontract.h>
#include <sys/contract/process.h>
#include <sys/ctfs.h>

#define CT_TEMPLATE     CTFS_ROOT "/process/template"
#define CT_LATEST       CTFS_ROOT "/process/latest"

static int tmpl_fd = -1;

/* Lookup the latest process contract */
static ctid_t
get_active_process_contract_id(void)
{
        int stat_fd;
        ctid_t ctid = -1;
        ct_stathdl_t stathdl;

        if ((stat_fd = open64(CT_LATEST, O_RDONLY)) == -1) {
                error("%s: Error opening 'latest' process "
                    "contract: %s", __func__, strerror(errno));
                return -1;
        }
        if (ct_status_read(stat_fd, CTD_COMMON, &stathdl) != 0) {
                error("%s: Error reading process contract "
                    "status: %s", __func__, strerror(errno));
                goto out;
        }
        if ((ctid = ct_status_get_id(stathdl)) < 0) {
                error("%s: Error getting process contract id: %s",
                    __func__, strerror(errno));
                goto out;
        }

        ct_status_free(stathdl);
 out:
        close(stat_fd);
        return ctid;
}

void
solaris_contract_pre_fork(void)
{
        if ((tmpl_fd = open64(CT_TEMPLATE, O_RDWR)) == -1) {
                error("%s: open %s: %s", __func__,
                    CT_TEMPLATE, strerror(errno));
                return;
        }

        debug2("%s: setting up process contract template on fd %d",
            __func__, tmpl_fd);

        /* First we set the template parameters and event sets. */
        if (ct_pr_tmpl_set_param(tmpl_fd, CT_PR_PGRPONLY) != 0) {
                error("%s: Error setting process contract parameter set "
                    "(pgrponly): %s", __func__, strerror(errno));
                goto fail;
        }
        if (ct_pr_tmpl_set_fatal(tmpl_fd, CT_PR_EV_HWERR) != 0) {
                error("%s: Error setting process contract template "
                    "fatal events: %s", __func__, strerror(errno));
                goto fail;
        }
        if (ct_tmpl_set_critical(tmpl_fd, 0) != 0) {
                error("%s: Error setting process contract template "
                    "critical events: %s", __func__, strerror(errno));
                goto fail;
        }
        if (ct_tmpl_set_informative(tmpl_fd, CT_PR_EV_HWERR) != 0) {
                error("%s: Error setting process contract template "
                    "informative events: %s", __func__, strerror(errno));
                goto fail;
        }

        /* Now make this the active template for this process. */
        if (ct_tmpl_activate(tmpl_fd) != 0) {
                error("%s: Error activating process contract "
                    "template: %s", __func__, strerror(errno));
                goto fail;
        }
        return;

 fail:
        if (tmpl_fd != -1) {
                close(tmpl_fd);
                tmpl_fd = -1;
        }
}

void
solaris_contract_post_fork_child()
{
        debug2("%s: clearing process contract template on fd %d",
            __func__, tmpl_fd);

        /* Clear the active template. */
        if (ct_tmpl_clear(tmpl_fd) != 0)
                error("%s: Error clearing active process contract "
                    "template: %s", __func__, strerror(errno));

        close(tmpl_fd);
        tmpl_fd = -1;
}

void
solaris_contract_post_fork_parent(pid_t pid)
{
        ctid_t ctid;
        char ctl_path[256];
        int r, ctl_fd = -1, stat_fd = -1;

        debug2("%s: clearing template (fd %d)", __func__, tmpl_fd);

        if (tmpl_fd == -1)
                return;

        /* First clear the active template. */
        if ((r = ct_tmpl_clear(tmpl_fd)) != 0)
                error("%s: Error clearing active process contract "
                    "template: %s", __func__, strerror(errno));

        close(tmpl_fd);
        tmpl_fd = -1;

        /*
         * If either the fork didn't succeed (pid < 0), or clearing
         * th active contract failed (r != 0), then we have nothing
         * more do.
         */
        if (r != 0 || pid <= 0)
                return;

        /* Now lookup and abandon the contract we've created. */
        ctid = get_active_process_contract_id();

        debug2("%s: abandoning contract id %ld", __func__, ctid);

        snprintf(ctl_path, sizeof(ctl_path),
            CTFS_ROOT "/process/%ld/ctl", ctid);
        if ((ctl_fd = open64(ctl_path, O_WRONLY)) < 0) {
                error("%s: Error opening process contract "
                    "ctl file: %s", __func__, strerror(errno));
                goto fail;
        }
        if (ct_ctl_abandon(ctl_fd) < 0) {
                error("%s: Error abandoning process contract: %s",
                    __func__, strerror(errno));
                goto fail;
        }
        close(ctl_fd);
        return;

 fail:
        if (tmpl_fd != -1) {
                close(tmpl_fd);
                tmpl_fd = -1;
        }
        if (stat_fd != -1)
                close(stat_fd);
        if (ctl_fd != -1)
                close(ctl_fd);
}
#endif

#ifdef USE_SOLARIS_PROJECTS
#include <sys/task.h>
#include <project.h>

/*
 * Get/set solaris default project.
 * If we fail, just run along gracefully.
 */
void
solaris_set_default_project(struct passwd *pw)
{
        struct project  *defaultproject;
        struct project   tempproject;
        char buf[1024];

        /* get default project, if we fail just return gracefully  */
        if ((defaultproject = getdefaultproj(pw->pw_name, &tempproject, &buf,
            sizeof(buf))) != NULL) {
                /* set default project */
                if (setproject(defaultproject->pj_name, pw->pw_name,
                    TASK_NORMAL) != 0)
                        debug("setproject(%s): %s", defaultproject->pj_name,
                            strerror(errno));
        } else {
                /* debug on getdefaultproj() error */
                debug("getdefaultproj(%s): %s", pw->pw_name, strerror(errno));
        }
}
#endif /* USE_SOLARIS_PROJECTS */

#ifdef USE_SOLARIS_PRIVS
# ifdef HAVE_PRIV_H
#  include <priv.h>
# endif

priv_set_t *
solaris_basic_privset(void)
{
        priv_set_t *pset;

#ifdef HAVE_PRIV_BASICSET
        if ((pset = priv_allocset()) == NULL) {
                error("priv_allocset: %s", strerror(errno));
                return NULL;
        }
        priv_basicset(pset);
#else
        if ((pset = priv_str_to_set("basic", ",", NULL)) == NULL) {
                error("priv_str_to_set: %s", strerror(errno));
                return NULL;
        }
#endif
        return pset;
}

void
solaris_drop_privs_pinfo_net_fork_exec(void)
{
        priv_set_t *pset = NULL, *npset = NULL;

        /*
         * Note: this variant avoids dropping DAC filesystem rights, in case
         * the process calling it is running as root and should have the
         * ability to read/write/chown any file on the system.
         *
         * We start with the basic set, then *add* the DAC rights to it while
         * taking away other parts of BASIC we don't need. Then we intersect
         * this with our existing PERMITTED set. In this way we keep any
         * DAC rights we had before, while otherwise reducing ourselves to
         * the minimum set of privileges we need to proceed.
         *
         * This also means we drop any other parts of "root" that we don't
         * need (e.g. the ability to kill any process, create new device nodes
         * etc etc).
         */

        if ((pset = priv_allocset()) == NULL)
                fatal("priv_allocset: %s", strerror(errno));
        if ((npset = solaris_basic_privset()) == NULL)
                fatal("solaris_basic_privset: %s", strerror(errno));

        if (priv_addset(npset, PRIV_FILE_CHOWN) != 0 ||
            priv_addset(npset, PRIV_FILE_DAC_READ) != 0 ||
            priv_addset(npset, PRIV_FILE_DAC_SEARCH) != 0 ||
            priv_addset(npset, PRIV_FILE_DAC_WRITE) != 0 ||
            priv_addset(npset, PRIV_FILE_OWNER) != 0)
                fatal("priv_addset: %s", strerror(errno));

        if (priv_delset(npset, PRIV_PROC_EXEC) != 0 ||
#ifdef PRIV_NET_ACCESS
            priv_delset(npset, PRIV_NET_ACCESS) != 0 ||
#endif
            priv_delset(npset, PRIV_PROC_FORK) != 0 ||
            priv_delset(npset, PRIV_PROC_INFO) != 0 ||
            priv_delset(npset, PRIV_PROC_SESSION) != 0)
                fatal("priv_delset: %s", strerror(errno));

#ifdef PRIV_XPOLICY
        /*
         * It is possible that the user has an extended policy
         * in place; the LIMIT set restricts the extended policy
         * and so should not be restricted.
         * PRIV_XPOLICY is newly defined in Solaris 11 though the extended
         * policy was not implemented until Solaris 11.1.
         */
        if (getpflags(PRIV_XPOLICY) == 1) {
                if (getppriv(PRIV_LIMIT, pset) != 0)
                        fatal("getppriv: %s", strerror(errno));
                priv_intersect(pset, npset);
                if (setppriv(PRIV_SET, PRIV_LIMIT, npset) != 0)
                        fatal("setppriv: %s", strerror(errno));
        } else
#endif
        {
                /* Cannot exec, so we can kill the limit set. */
                priv_emptyset(pset);
                if (setppriv(PRIV_SET, PRIV_LIMIT, pset) != 0)
                        fatal("setppriv: %s", strerror(errno));
        }

        if (getppriv(PRIV_PERMITTED, pset) != 0)
                fatal("getppriv: %s", strerror(errno));

        priv_intersect(pset, npset);

        if (setppriv(PRIV_SET, PRIV_PERMITTED, npset) != 0 ||
            setppriv(PRIV_SET, PRIV_INHERITABLE, npset) != 0)
                fatal("setppriv: %s", strerror(errno));

        priv_freeset(pset);
        priv_freeset(npset);
}

void
solaris_drop_privs_root_pinfo_net(void)
{
        priv_set_t *pset = NULL;

        /* Start with "basic" and drop everything we don't need. */
        if ((pset = solaris_basic_privset()) == NULL)
                fatal("solaris_basic_privset: %s", strerror(errno));

        if (priv_delset(pset, PRIV_FILE_LINK_ANY) != 0 ||
#ifdef PRIV_NET_ACCESS
            priv_delset(pset, PRIV_NET_ACCESS) != 0 ||
#endif
            priv_delset(pset, PRIV_PROC_INFO) != 0 ||
            priv_delset(pset, PRIV_PROC_SESSION) != 0)
                fatal("priv_delset: %s", strerror(errno));

        if (setppriv(PRIV_SET, PRIV_PERMITTED, pset) != 0 ||
            setppriv(PRIV_SET, PRIV_LIMIT, pset) != 0 ||
            setppriv(PRIV_SET, PRIV_INHERITABLE, pset) != 0)
                fatal("setppriv: %s", strerror(errno));

        priv_freeset(pset);
}

void
solaris_drop_privs_root_pinfo_net_exec(void)
{
        priv_set_t *pset = NULL;


        /* Start with "basic" and drop everything we don't need. */
        if ((pset = solaris_basic_privset()) == NULL)
                fatal("solaris_basic_privset: %s", strerror(errno));

        if (priv_delset(pset, PRIV_FILE_LINK_ANY) != 0 ||
#ifdef PRIV_NET_ACCESS
            priv_delset(pset, PRIV_NET_ACCESS) != 0 ||
#endif
            priv_delset(pset, PRIV_PROC_EXEC) != 0 ||
            priv_delset(pset, PRIV_PROC_INFO) != 0)
                fatal("priv_delset: %s", strerror(errno));

        if (setppriv(PRIV_SET, PRIV_PERMITTED, pset) != 0 ||
            setppriv(PRIV_SET, PRIV_LIMIT, pset) != 0 ||
            setppriv(PRIV_SET, PRIV_INHERITABLE, pset) != 0)
                fatal("setppriv: %s", strerror(errno));

        priv_freeset(pset);
}

#endif