libdladm/common/libdladm.c

	libdladm.c revision f595a68a3b8953a12aa778c2abd7642df8da8c3a
/*
 * 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.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <unistd.h>
#include <stropts.h>
#include <errno.h>
#include <fcntl.h>
#include <strings.h>
#include <dirent.h>
#include <sys/stat.h>
#include <libdladm.h>
#include <libdladm_impl.h>
#include <libintl.h>

static char     dladm_rootdir[MAXPATHLEN] = "/";

/*
 * Issue an ioctl to the specified file descriptor attached to the
 * DLD control driver interface.
 */
int
i_dladm_ioctl(int fd, int ic_cmd, void *ic_dp, int ic_len)
{
    struct strioctl iocb;

    iocb.ic_cmd = ic_cmd;
    iocb.ic_timout = 0;
    iocb.ic_len = ic_len;
    iocb.ic_dp = (char *)ic_dp;

    return (ioctl(fd, I_STR, &iocb));
}

const char *
dladm_status2str(dladm_status_t status, char *buf)
{
    const char  *s;

    switch (status) {
    case DLADM_STATUS_OK:
        s = "ok";
        break;
    case DLADM_STATUS_BADARG:
        s = "invalid argument";
        break;
    case DLADM_STATUS_FAILED:
        s = "operation failed";
        break;
    case DLADM_STATUS_TOOSMALL:
        s = "buffer size too small";
        break;
    case DLADM_STATUS_NOTSUP:
        s = "operation not supported";
        break;
    case DLADM_STATUS_NOTFOUND:
        s = "object not found";
        break;
    case DLADM_STATUS_BADVAL:
        s = "invalid value";
        break;
    case DLADM_STATUS_NOMEM:
        s = "insufficient memory";
        break;
    case DLADM_STATUS_EXIST:
        s = "object already exists";
        break;
    case DLADM_STATUS_LINKINVAL:
        s = "invalid link";
        break;
    case DLADM_STATUS_PROPRDONLY:
        s = "read-only property";
        break;
    case DLADM_STATUS_BADVALCNT:
        s = "invalid number of values";
        break;
    case DLADM_STATUS_DBNOTFOUND:
        s = "database not found";
        break;
    case DLADM_STATUS_DENIED:
        s = "permission denied";
        break;
    case DLADM_STATUS_IOERR:
        s = "I/O error";
        break;
    case DLADM_STATUS_TEMPONLY:
        s = "change cannot be persistent, specify -t please";
        break;
    case DLADM_STATUS_TIMEDOUT:
        s = "operation timed out";
        break;
    case DLADM_STATUS_ISCONN:
        s = "already connected";
        break;
    case DLADM_STATUS_NOTCONN:
        s = "not connected";
        break;
    case DLADM_STATUS_REPOSITORYINVAL:
        s = "invalid configuration repository";
        break;
    case DLADM_STATUS_MACADDRINVAL:
        s = "invalid MAC address";
        break;
    case DLADM_STATUS_KEYINVAL:
        s = "invalid key";
        break;
    default:
        s = "<unknown error>";
        break;
    }
    (void) snprintf(buf, DLADM_STRSIZE, "%s", dgettext(TEXT_DOMAIN, s));
    return (buf);
}

/*
 * Convert a unix errno to a dladm_status_t.
 * We only convert errnos that are likely to be encountered. All others
 * are mapped to DLADM_STATUS_FAILED.
 */
dladm_status_t
dladm_errno2status(int err)
{
    switch (err) {
    case EINVAL:
        return (DLADM_STATUS_BADARG);
    case EEXIST:
        return (DLADM_STATUS_EXIST);
    case ENOENT:
        return (DLADM_STATUS_NOTFOUND);
    case ENOSPC:
        return (DLADM_STATUS_TOOSMALL);
    case ENOMEM:
        return (DLADM_STATUS_NOMEM);
    case ENOTSUP:
        return (DLADM_STATUS_NOTSUP);
    case EACCES:
        return (DLADM_STATUS_DENIED);
    case EIO:
        return (DLADM_STATUS_IOERR);
    default:
        return (DLADM_STATUS_FAILED);
    }
}

/*
 * These are the uid and gid of the user 'dladm'.
 * The directory /etc/dladm and all files under it are owned by this user.
 */
#define DLADM_DB_OWNER      15
#define DLADM_DB_GROUP      3
#define LOCK_DB_PERMS       S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH

static int
i_dladm_lock_db(const char *lock_file, short type)
{
    int lock_fd;
    struct  flock lock;

    if ((lock_fd = open(lock_file, O_RDWR | O_CREAT | O_TRUNC,
        LOCK_DB_PERMS)) < 0)
        return (-1);

    lock.l_type = type;
    lock.l_whence = SEEK_SET;
    lock.l_start = 0;
    lock.l_len = 0;

    if (fcntl(lock_fd, F_SETLKW, &lock) < 0) {
        int err = errno;

        (void) close(lock_fd);
        (void) unlink(lock_file);
        errno = err;
        return (-1);
    }
    return (lock_fd);
}

static void
i_dladm_unlock_db(const char *lock_file, int fd)
{
    struct flock lock;

    if (fd < 0)
        return;

    lock.l_type = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = 0;
    lock.l_len = 0;

    (void) fcntl(fd, F_SETLKW, &lock);
    (void) close(fd);
    (void) unlink(lock_file);
}

dladm_status_t
i_dladm_rw_db(const char *db_file, mode_t db_perms,
    dladm_status_t (*process_db)(void *, FILE *, FILE *),
    void *arg, boolean_t writeop)
{
    dladm_status_t  status = DLADM_STATUS_OK;
    FILE        *fp, *nfp = NULL;
    char        lock[MAXPATHLEN];
    char        file[MAXPATHLEN];
    char        newfile[MAXPATHLEN];
    char        *db_basename;
    int     nfd, lock_fd;

    /*
     * If we are called from a boot script such as net-physical,
     * it's quite likely that the root fs is still not writable.
     * For this case, it's ok for the lock creation to fail since
     * no one else could be accessing our configuration file.
     */
    db_basename = strrchr(db_file, '/');
    if (db_basename == NULL || db_basename[1] == '\0')
        return (dladm_errno2status(EINVAL));
    db_basename++;
    (void) snprintf(lock, MAXPATHLEN, "/tmp/%s.lock", db_basename);
    if ((lock_fd = i_dladm_lock_db
        (lock, (writeop ? F_WRLCK : F_RDLCK))) < 0 && errno != EROFS)
        return (dladm_errno2status(errno));

    (void) snprintf(file, MAXPATHLEN, "%s/%s", dladm_rootdir, db_file);
    if ((fp = fopen(file, (writeop ? "r+" : "r"))) == NULL) {
        int err = errno;

        i_dladm_unlock_db(lock, lock_fd);
        if (err == ENOENT)
            return (DLADM_STATUS_DBNOTFOUND);

        return (dladm_errno2status(err));
    }

    if (writeop) {
        (void) snprintf(newfile, MAXPATHLEN, "%s/%s.new",
            dladm_rootdir, db_file);
        if ((nfd = open(newfile, O_WRONLY | O_CREAT | O_TRUNC,
            db_perms)) < 0) {
            (void) fclose(fp);
            i_dladm_unlock_db(lock, lock_fd);
            return (dladm_errno2status(errno));
        }

        if ((nfp = fdopen(nfd, "w")) == NULL) {
            (void) close(nfd);
            (void) fclose(fp);
            (void) unlink(newfile);
            i_dladm_unlock_db(lock, lock_fd);
            return (dladm_errno2status(errno));
        }
    }
    status = (*process_db)(arg, fp, nfp);
    if (!writeop || status != DLADM_STATUS_OK)
        goto done;

    /*
     * Configuration files need to be owned by the 'dladm' user.
     * If we are invoked by root, the file ownership needs to be fixed.
     */
    if (getuid() == 0 || geteuid() == 0) {
        if (fchown(nfd, DLADM_DB_OWNER, DLADM_DB_GROUP) < 0) {
            status = dladm_errno2status(errno);
            goto done;
        }
    }

    if (fflush(nfp) == EOF) {
        status = dladm_errno2status(errno);
        goto done;
    }
    (void) fclose(fp);
    (void) fclose(nfp);

    if (rename(newfile, file) < 0) {
        (void) unlink(newfile);
        i_dladm_unlock_db(lock, lock_fd);
        return (dladm_errno2status(errno));
    }

    i_dladm_unlock_db(lock, lock_fd);
    return (DLADM_STATUS_OK);

done:
    if (nfp != NULL) {
        (void) fclose(nfp);
        if (status != DLADM_STATUS_OK)
            (void) unlink(newfile);
    }
    (void) fclose(fp);
    i_dladm_unlock_db(lock, lock_fd);
    return (status);
}

dladm_status_t
dladm_set_rootdir(const char *rootdir)
{
    DIR *dp;

    if (rootdir == NULL || *rootdir != '/' ||
        (dp = opendir(rootdir)) == NULL)
        return (DLADM_STATUS_BADARG);

    (void) strncpy(dladm_rootdir, rootdir, MAXPATHLEN);
    (void) closedir(dp);
    return (DLADM_STATUS_OK);
}