libsmbfs/smb/rcfile.c

	rcfile.c revision 613a2f6ba31e891e3d947a356daf5e563d43c1ce
/*
 * Copyright (c) 2000, Boris Popov
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by Boris Popov.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: rcfile.c,v 1.1.1.2 2001/07/06 22:38:43 conrad Exp $
 */

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

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <stdlib.h>
#include <synch.h>
#include <unistd.h>
#include <pwd.h>
#include <libintl.h>

#include <cflib.h>
#include "rcfile_priv.h"

#include <assert.h>

#if 0 /* before SMF */
#define SMB_CFG_FILE    "/etc/nsmb.conf"
#define OLD_SMB_CFG_FILE    "/usr/local/etc/nsmb.conf"
#endif
#define SMBFS_SHARECTL_CMD  "/usr/sbin/sharectl get smbfs"

extern int smb_debug;

static struct rcfile *rc_cachelookup(const char *filename);
static struct rcsection *rc_findsect(struct rcfile *rcp, const char *sectname);
static struct rcsection *rc_addsect(struct rcfile *rcp, const char *sectname);
static int      rc_freesect(struct rcfile *rcp, struct rcsection *rsp);
static struct rckey *rc_sect_findkey(struct rcsection *rsp, const char *key);
static struct rckey *rc_sect_addkey(struct rcsection *rsp, const char *name,
    const char *value);
static void rc_key_free(struct rckey *p);
static void rc_parse(struct rcfile *rcp);

/* lock for the variables below */
mutex_t rcfile_mutex = DEFAULTMUTEX;

SLIST_HEAD(rcfile_head, rcfile);
static struct rcfile_head pf_head = {NULL};
struct rcfile *smb_rc;
int home_nsmbrc;
int insecure_nsmbrc;

/*
 * open rcfile and load its content, if already open - return previous handle
 */
static int
rc_open(const char *filename, const char *mode, struct rcfile **rcfile)
{
    struct stat statbuf;
    struct rcfile *rcp;
    FILE *f;

    assert(MUTEX_HELD(&rcfile_mutex));

    rcp = rc_cachelookup(filename);
    if (rcp) {
        *rcfile = rcp;
        return (0);
    }
    f = fopen(filename, mode);
    if (f == NULL)
        return (errno);
    insecure_nsmbrc = 0;
    if (fstat(fileno(f), &statbuf) >= 0 &&
        (statbuf.st_mode & 077) != 0)
        insecure_nsmbrc = 1;
    rcp = malloc(sizeof (struct rcfile));
    if (rcp == NULL) {
        fclose(f);
        return (ENOMEM);
    }
    bzero(rcp, sizeof (struct rcfile));
    rcp->rf_name = strdup(filename);
    rcp->rf_f = f;
    SLIST_INSERT_HEAD(&pf_head, rcp, rf_next);
    rc_parse(rcp);
    *rcfile = rcp;
    return (0);
}

static int
rc_merge(const char *filename, struct rcfile **rcfile)
{
    struct stat statbuf;
    struct rcfile *rcp = *rcfile;
    FILE *f, *t;

    assert(MUTEX_HELD(&rcfile_mutex));

    insecure_nsmbrc = 0;
    if (rcp == NULL) {
        return (rc_open(filename, "r", rcfile));
    }
    f = fopen(filename, "r");
    if (f == NULL)
        return (errno);
    insecure_nsmbrc = 0;
    if (fstat(fileno(f), &statbuf) >= 0 &&
        (statbuf.st_mode & 077) != 0)
        insecure_nsmbrc = 1;
    t = rcp->rf_f;
    rcp->rf_f = f;
    rc_parse(rcp);
    rcp->rf_f = t;
    fclose(f);
    return (0);
}

/*
 * Like rc_open, but does popen of command:
 * sharectl get smbfs
 */
static int
rc_popen_cmd(const char *command, struct rcfile **rcfile)
{
    struct rcfile *rcp;
    FILE *f;

    assert(MUTEX_HELD(&rcfile_mutex));

    f = popen(command, "r");
    if (f == NULL)
        return (errno);
    insecure_nsmbrc = 0;

    rcp = malloc(sizeof (struct rcfile));
    if (rcp == NULL) {
        fclose(f);
        return (ENOMEM);
    }
    bzero(rcp, sizeof (struct rcfile));
    rcp->rf_name = strdup(command);
    rcp->rf_f = f;
    SLIST_INSERT_HEAD(&pf_head, rcp, rf_next);
    rc_parse(rcp);
    *rcfile = rcp;
    /* fclose(f) in rc_close */
    return (0);
}

static int
rc_close(struct rcfile *rcp)
{
    struct rcsection *p, *n;

    mutex_lock(&rcfile_mutex);

    fclose(rcp->rf_f);
    for (p = SLIST_FIRST(&rcp->rf_sect); p; ) {
        n = p;
        p = SLIST_NEXT(p, rs_next);
        rc_freesect(rcp, n);
    }
    free(rcp->rf_name);
    SLIST_REMOVE(&pf_head, rcp, rcfile, rf_next);
    free(rcp);

    mutex_unlock(&rcfile_mutex);
    return (0);
}

static struct rcfile *
rc_cachelookup(const char *filename)
{
    struct rcfile *p;

    assert(MUTEX_HELD(&rcfile_mutex));

    SLIST_FOREACH(p, &pf_head, rf_next)
        if (strcmp(filename, p->rf_name) == 0)
            return (p);
    return (0);
}

static struct rcsection *
rc_findsect(struct rcfile *rcp, const char *sectname)
{
    struct rcsection *p;

    assert(MUTEX_HELD(&rcfile_mutex));

    SLIST_FOREACH(p, &rcp->rf_sect, rs_next)
        if (strcasecmp(p->rs_name, sectname) == 0)
            return (p);
    return (NULL);
}

static struct rcsection *
rc_addsect(struct rcfile *rcp, const char *sectname)
{
    struct rcsection *p;

    assert(MUTEX_HELD(&rcfile_mutex));

    p = rc_findsect(rcp, sectname);
    if (p)
        return (p);
    p = malloc(sizeof (*p));
    if (!p)
        return (NULL);
    p->rs_name = strdup(sectname);
    SLIST_INIT(&p->rs_keys);
    SLIST_INSERT_HEAD(&rcp->rf_sect, p, rs_next);
    return (p);
}

static int
rc_freesect(struct rcfile *rcp, struct rcsection *rsp)
{
    struct rckey *p, *n;

    assert(MUTEX_HELD(&rcfile_mutex));

    SLIST_REMOVE(&rcp->rf_sect, rsp, rcsection, rs_next);
    for (p = SLIST_FIRST(&rsp->rs_keys); p; ) {
        n = p;
        p = SLIST_NEXT(p, rk_next);
        rc_key_free(n);
    }
    free(rsp->rs_name);
    free(rsp);
    return (0);
}

static struct rckey *
rc_sect_findkey(struct rcsection *rsp, const char *keyname)
{
    struct rckey *p;

    assert(MUTEX_HELD(&rcfile_mutex));

    SLIST_FOREACH(p, &rsp->rs_keys, rk_next)
        if (strcmp(p->rk_name, keyname) == 0)
            return (p);
    return (NULL);
}

static struct rckey *
rc_sect_addkey(struct rcsection *rsp, const char *name, const char *value)
{
    struct rckey *p;

    assert(MUTEX_HELD(&rcfile_mutex));

    p = rc_sect_findkey(rsp, name);
    if (!p) {
        p = malloc(sizeof (*p));
        if (!p)
            return (NULL);
        SLIST_INSERT_HEAD(&rsp->rs_keys, p, rk_next);
        p->rk_name = strdup(name);
        p->rk_value = value ? strdup(value) : strdup("");
    }
    return (p);
}

#if 0
void
rc_sect_delkey(struct rcsection *rsp, struct rckey *p)
{

    SLIST_REMOVE(&rsp->rs_keys, p, rckey, rk_next);
    rc_key_free(p);
}
#endif

static void
rc_key_free(struct rckey *p)
{
    free(p->rk_value);
    free(p->rk_name);
    free(p);
}


static char *minauth_values[] = {
    "none",
    "lm",
    "ntlm",
    "ntlmv2",
    "kerberos",
    NULL
};

static int
eval_minauth(char *auth)
{
    int i;

    for (i = 0; minauth_values[i]; i++)
        if (strcmp(auth, minauth_values[i]) == 0)
            return (i);
    return (-1);
}

/*
 * Ensure that "minauth" is set to the highest level
 */
/*ARGSUSED*/
static void
set_value(struct rcfile *rcp, struct rcsection *rsp, struct rckey *rkp,
    char *ptr)
{
    int now, new;
#ifdef DEBUG
    char *from;

    if (smb_debug)
        from = (home_nsmbrc) ?
            "user file" : "SMF";
#endif

    if (strcmp(rkp->rk_name, "minauth") == 0) {
        now = eval_minauth(rkp->rk_value);
        new = eval_minauth(ptr);
        if (new <= now) {
#ifdef DEBUG
            if (smb_debug)
                fprintf(stderr,
                    "set_value: rejecting %s=%s"
                    " in %s from %s\n",
                    rkp->rk_name, ptr,
                    rsp->rs_name, from);
#endif
            return;
        }
    }
#ifdef DEBUG
    if (smb_debug)
        fprintf(stderr,
            "set_value: applying %s=%s in %s from %s\n",
            rkp->rk_name, ptr, rsp->rs_name, from);
#endif
    rkp->rk_value = strdup(ptr);
}


/* states in rc_parse */
enum { stNewLine, stHeader, stSkipToEOL, stGetKey, stGetValue};

static void
rc_parse(struct rcfile *rcp)
{
    FILE *f = rcp->rf_f;
    int state = stNewLine, c;
    struct rcsection *rsp = NULL;
    struct rckey *rkp = NULL;
    char buf[2048];
    char *next = buf, *last = &buf[sizeof (buf)-1];

    assert(MUTEX_HELD(&rcfile_mutex));

    while ((c = getc(f)) != EOF) {
        if (c == '\r')
            continue;
        if (state == stNewLine) {
            next = buf;
            if (isspace(c))
                continue;   /* skip leading junk */
            if (c == '[') {
                state = stHeader;
                rsp = NULL;
                continue;
            }
            if (c == '#' || c == ';') {
                state = stSkipToEOL;
            } else {        /* something meaningfull */
                state = stGetKey;
            }
        }
        /* ignore long lines */
        if (state == stSkipToEOL || next == last) {
            if (c == '\n') {
                state = stNewLine;
                next = buf;
            }
            continue;
        }
        if (state == stHeader) {
            if (c == ']') {
                *next = 0;
                next = buf;
                rsp = rc_addsect(rcp, buf);
                state = stSkipToEOL;
            } else
                *next++ = c;
            continue;
        }
        if (state == stGetKey) {
            /* side effect: 'key name=' */
            if (c == ' ' || c == '\t')
                continue;   /* become 'keyname=' */
            if (c == '\n') {    /* silently ignore ... */
                state = stNewLine;
                continue;
            }
            if (c != '=') {
                *next++ = c;
                continue;
            }
            *next = 0;
            if (rsp == NULL) {
                fprintf(stderr, dgettext(TEXT_DOMAIN,
                    "Key '%s' defined before section\n"), buf);
                state = stSkipToEOL;
                continue;
            }
            if (home_nsmbrc != 0 && (
                strcmp(buf, "nbns") == 0 ||
                strcmp(buf, "nbns_enable") == 0 ||
                strcmp(buf, "nbns_broadcast") == 0 ||
                strcmp(buf, "signing") == 0)) {
                fprintf(stderr, dgettext(TEXT_DOMAIN,
                    "option %s may not be set "
                    "in user .nsmbrc file\n"), buf);
                next = buf;
                state = stNewLine;
                continue;
            }
            if (insecure_nsmbrc != 0 &&
                strcmp(buf, "password") == 0) {
                fprintf(stderr, dgettext(TEXT_DOMAIN,
                    "Warning: .nsmbrc file not secure, "
                    "ignoring passwords\n"));
                next = buf;
                state = stNewLine;
                continue;
            }
            rkp = rc_sect_addkey(rsp, buf, NULL);
            next = buf;
            state = stGetValue;
            continue;
        }
        /* only stGetValue left */
        if (state != stGetValue) {
            fprintf(stderr, dgettext(TEXT_DOMAIN,
                "Well, I can't parse file '%s'\n"), rcp->rf_name);
            state = stSkipToEOL;
        }
        if (c != '\n') {
            *next++ = c;
            continue;
        }
        *next = 0;
        set_value(rcp, rsp, rkp, buf);
        state = stNewLine;
        rkp = NULL;
    }   /* while */
    if (c == EOF && state == stGetValue) {
        *next = 0;
        set_value(rcp, rsp, rkp, buf);
    }
}

int
rc_getstringptr(struct rcfile *rcp, const char *section, const char *key,
    char **dest)
{
    struct rcsection *rsp;
    struct rckey *rkp;
    int err;

    mutex_lock(&rcfile_mutex);

    *dest = NULL;
    rsp = rc_findsect(rcp, section);
    if (!rsp) {
        err = ENOENT;
        goto out;
    }
    rkp = rc_sect_findkey(rsp, key);
    if (!rkp) {
        err = ENOENT;
        goto out;
    }
    *dest = rkp->rk_value;
    err = 0;

out:
    mutex_unlock(&rcfile_mutex);
    return (err);
}

int
rc_getstring(struct rcfile *rcp, const char *section, const char *key,
    size_t maxlen, char *dest)
{
    char *value;
    int error;

    error = rc_getstringptr(rcp, section, key, &value);
    if (error)
        return (error);
    if (strlen(value) >= maxlen) {
        fprintf(stderr, dgettext(TEXT_DOMAIN,
            "line too long for key '%s' in section '%s', max = %d\n"),
            key, section, maxlen);
        return (EINVAL);
    }
    strcpy(dest, value);
    return (0);
}

int
rc_getint(struct rcfile *rcp, const char *section, const char *key, int *value)
{
    struct rcsection *rsp;
    struct rckey *rkp;
    int err;

    mutex_lock(&rcfile_mutex);

    rsp = rc_findsect(rcp, section);
    if (!rsp) {
        err = ENOENT;
        goto out;
    }
    rkp = rc_sect_findkey(rsp, key);
    if (!rkp) {
        err = ENOENT;
        goto out;
    }
    errno = 0;
    *value = strtol(rkp->rk_value, NULL, 0);
    if ((err = errno) != 0) {
        fprintf(stderr, dgettext(TEXT_DOMAIN,
            "invalid int value '%s' for key '%s' in section '%s'\n"),
            rkp->rk_value, key, section);
    }

out:
    mutex_unlock(&rcfile_mutex);
    return (err);
}

/*
 * 1,yes,true
 * 0,no,false
 */
int
rc_getbool(struct rcfile *rcp, const char *section, const char *key, int *value)
{
    struct rcsection *rsp;
    struct rckey *rkp;
    char *p;
    int err;

    mutex_lock(&rcfile_mutex);

    rsp = rc_findsect(rcp, section);
    if (!rsp) {
        err = ENOENT;
        goto out;
    }
    rkp = rc_sect_findkey(rsp, key);
    if (!rkp) {
        err = ENOENT;
        goto out;
    }
    p = rkp->rk_value;
    while (*p && isspace(*p)) p++;
    if (*p == '0' ||
        strcasecmp(p, "no") == 0 ||
        strcasecmp(p, "false") == 0) {
        *value = 0;
        err = 0;
        goto out;
    }
    if (*p == '1' ||
        strcasecmp(p, "yes") == 0 ||
        strcasecmp(p, "true") == 0) {
        *value = 1;
        err = 0;
        goto out;
    }
    fprintf(stderr, dgettext(TEXT_DOMAIN,
        "invalid boolean value '%s' for key '%s' in section '%s' \n"),
        p, key, section);
    err = EINVAL;

out:
    mutex_unlock(&rcfile_mutex);
    return (err);
}

#ifdef DEBUG
void
dump_props(char *where)
{
    struct rcsection *rsp = NULL;
    struct rckey *rkp = NULL;

    fprintf(stderr, "Settings %s\n", where);
    SLIST_FOREACH(rsp, &smb_rc->rf_sect, rs_next) {
        fprintf(stderr, "section=%s\n", rsp->rs_name);
        fflush(stderr);

        SLIST_FOREACH(rkp, &rsp->rs_keys, rk_next) {
            fprintf(stderr, "  key=%s, value=%s\n",
                rkp->rk_name, rkp->rk_value);
            fflush(stderr);
        }
    }
}
#endif

/*
 * first parse "sharectl get smbfs, then $HOME/.nsmbrc
 * This is called by library consumers (commands)
 */
int
smb_open_rcfile(char *home)
{
    char *fn;
    int len, error = 0;

    mutex_lock(&rcfile_mutex);

    smb_rc = NULL;
#if 0   /* before SMF */
    fn = SMB_CFG_FILE;
    error = rc_open(fn, &smb_rc);
#else
    fn = SMBFS_SHARECTL_CMD;
    error = rc_popen_cmd(fn, &smb_rc);
#endif
    if (error != 0 && error != ENOENT) {
        /* Error from fopen. strerror is OK. */
        fprintf(stderr, dgettext(TEXT_DOMAIN,
            "Can't open %s: %s\n"), fn, strerror(errno));
    }
#ifdef DEBUG
    if (smb_debug)
        dump_props(fn);
#endif

    if (home) {
        len = strlen(home) + 20;
        fn = malloc(len);
        snprintf(fn, len, "%s/.nsmbrc", home);
        home_nsmbrc = 1;
        error = rc_merge(fn, &smb_rc);
        if (error != 0 && error != ENOENT) {
            fprintf(stderr, dgettext(TEXT_DOMAIN,
                "Can't open %s: %s\n"), fn, strerror(errno));
        }
        home_nsmbrc = 0;
#ifdef DEBUG
        if (smb_debug)
            dump_props(fn);
#endif
        free(fn);
    }

    /* Mostly ignore error returns above. */
    if (smb_rc == NULL)
        error = ENOENT;
    else
        error = 0;

    mutex_unlock(&rcfile_mutex);

    return (error);
}

/*
 * This is called by library consumers (commands)
 */
void
smb_close_rcfile(void)
{
    struct rcfile *rcp;

    if ((rcp = smb_rc) != NULL) {
        smb_rc = NULL;
        rc_close(rcp);
    }
}