NetBSD/libexec/ftpd/conf.c

852 lines
20 KiB
C

/* $NetBSD: conf.c,v 1.32 2000/07/09 02:24:30 sommerfeld Exp $ */
/*-
* Copyright (c) 1997-2000 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Simon Burge and Luke Mewburn.
*
* 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 the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: conf.c,v 1.32 2000/07/09 02:24:30 sommerfeld Exp $");
#endif /* not lint */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <glob.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stringlist.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
#include <util.h>
#ifdef KERBEROS5
#include <krb5/krb5.h>
#endif
#include "extern.h"
#include "pathnames.h"
static char *strend(const char *, char *);
static int filetypematch(char *, int);
/*
* Initialise curclass to an `empty' state
*/
void
init_curclass(void)
{
struct ftpconv *conv, *cnext;
for (conv = curclass.conversions; conv != NULL; conv = cnext) {
REASSIGN(conv->suffix, NULL);
REASSIGN(conv->types, NULL);
REASSIGN(conv->disable, NULL);
REASSIGN(conv->command, NULL);
cnext = conv->next;
free(conv);
}
curclass.checkportcmd = 0;
REASSIGN(curclass.classname, NULL);
curclass.conversions = NULL;
REASSIGN(curclass.display, NULL);
curclass.limit = -1; /* unlimited connections */
REASSIGN(curclass.limitfile, NULL);
curclass.maxrateget = 0;
curclass.maxrateput = 0;
curclass.maxtimeout = 7200; /* 2 hours */
curclass.modify = 1;
REASSIGN(curclass.motd, xstrdup(_PATH_FTPLOGINMESG));
REASSIGN(curclass.notify, NULL);
curclass.passive = 1;
curclass.portmin = 0;
curclass.portmax = 0;
curclass.rateget = 0;
curclass.rateput = 0;
curclass.timeout = 900; /* 15 minutes */
curclass.umask = 027;
curclass.upload = 1;
}
/*
* Parse the configuration file, looking for the named class, and
* define curclass to contain the appropriate settings.
*/
void
parse_conf(const char *findclass)
{
FILE *f;
char *buf, *p;
size_t len;
int none, match, rate;
char *endp;
char *class, *word, *arg, *template;
const char *infile;
size_t line;
unsigned int timeout;
struct ftpconv *conv, *cnext;
init_curclass();
REASSIGN(curclass.classname, xstrdup(findclass));
if (strcasecmp(findclass, "guest") == 0) {
curclass.modify = 0;
curclass.umask = 0707;
}
infile = conffilename(_PATH_FTPDCONF);
if ((f = fopen(infile, "r")) == NULL)
return;
line = 0;
template = NULL;
for (;
(buf = fparseln(f, &len, &line, NULL, FPARSELN_UNESCCOMM |
FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL;
free(buf)) {
none = match = 0;
p = buf;
if (len < 1)
continue;
if (p[len - 1] == '\n')
p[--len] = '\0';
if (EMPTYSTR(p))
continue;
NEXTWORD(p, word);
NEXTWORD(p, class);
NEXTWORD(p, arg);
if (EMPTYSTR(word) || EMPTYSTR(class))
continue;
if (strcasecmp(class, "none") == 0)
none = 1;
if (! (strcasecmp(class, findclass) == 0 ||
(template != NULL && strcasecmp(class, template) == 0) ||
none ||
strcasecmp(class, "all") == 0) )
continue;
if (strcasecmp(word, "checkportcmd") == 0) {
if (none ||
(!EMPTYSTR(arg) && strcasecmp(arg, "off") == 0))
curclass.checkportcmd = 0;
else
curclass.checkportcmd = 1;
} else if (strcasecmp(word, "classtype") == 0) {
if (!none && !EMPTYSTR(arg)) {
if (strcasecmp(arg, "GUEST") == 0)
curclass.type = CLASS_GUEST;
else if (strcasecmp(arg, "CHROOT") == 0)
curclass.type = CLASS_CHROOT;
else if (strcasecmp(arg, "REAL") == 0)
curclass.type = CLASS_REAL;
else {
syslog(LOG_WARNING,
"%s line %d: unknown class type `%s'",
infile, (int)line, arg);
continue;
}
}
} else if (strcasecmp(word, "conversion") == 0) {
char *suffix, *types, *disable, *convcmd;
if (EMPTYSTR(arg)) {
syslog(LOG_WARNING,
"%s line %d: %s requires a suffix",
infile, (int)line, word);
continue; /* need a suffix */
}
NEXTWORD(p, types);
NEXTWORD(p, disable);
convcmd = p;
if (convcmd)
convcmd += strspn(convcmd, " \t");
suffix = xstrdup(arg);
if (none || EMPTYSTR(types) ||
EMPTYSTR(disable) || EMPTYSTR(convcmd)) {
types = NULL;
disable = NULL;
convcmd = NULL;
} else {
types = xstrdup(types);
disable = xstrdup(disable);
convcmd = xstrdup(convcmd);
}
for (conv = curclass.conversions; conv != NULL;
conv = conv->next) {
if (strcmp(conv->suffix, suffix) == 0)
break;
}
if (conv == NULL) {
conv = (struct ftpconv *)
calloc(1, sizeof(struct ftpconv));
if (conv == NULL) {
syslog(LOG_WARNING, "can't malloc");
continue;
}
conv->next = NULL;
for (cnext = curclass.conversions;
cnext != NULL; cnext = cnext->next)
if (cnext->next == NULL)
break;
if (cnext != NULL)
cnext->next = conv;
else
curclass.conversions = conv;
}
REASSIGN(conv->suffix, suffix);
REASSIGN(conv->types, types);
REASSIGN(conv->disable, disable);
REASSIGN(conv->command, convcmd);
} else if (strcasecmp(word, "display") == 0) {
if (none || EMPTYSTR(arg))
arg = NULL;
else
arg = xstrdup(arg);
REASSIGN(curclass.display, arg);
} else if (strcasecmp(word, "limit") == 0) {
int limit;
if (none || EMPTYSTR(arg))
continue;
limit = (int)strtol(arg, &endp, 10);
if (*endp != 0) {
syslog(LOG_WARNING,
"%s line %d: invalid limit %s",
infile, (int)line, arg);
continue;
}
curclass.limit = limit;
REASSIGN(curclass.limitfile,
EMPTYSTR(p) ? NULL : xstrdup(p));
} else if (strcasecmp(word, "maxtimeout") == 0) {
if (none || EMPTYSTR(arg))
continue;
timeout = (unsigned int)strtoul(arg, &endp, 10);
if (*endp != 0) {
syslog(LOG_WARNING,
"%s line %d: invalid maxtimeout %s",
infile, (int)line, arg);
continue;
}
if (timeout < 30) {
syslog(LOG_WARNING,
"%s line %d: maxtimeout %d < 30 seconds",
infile, (int)line, timeout);
continue;
}
if (timeout < curclass.timeout) {
syslog(LOG_WARNING,
"%s line %d: maxtimeout %d < timeout (%d)",
infile, (int)line, timeout,
curclass.timeout);
continue;
}
curclass.maxtimeout = timeout;
} else if (strcasecmp(word, "modify") == 0) {
if (none ||
(!EMPTYSTR(arg) && strcasecmp(arg, "off") == 0))
curclass.modify = 0;
else
curclass.modify = 1;
} else if (strcasecmp(word, "motd") == 0) {
if (none || EMPTYSTR(arg))
arg = NULL;
else
arg = xstrdup(arg);
REASSIGN(curclass.motd, arg);
} else if (strcasecmp(word, "notify") == 0) {
if (none || EMPTYSTR(arg))
arg = NULL;
else
arg = xstrdup(arg);
REASSIGN(curclass.notify, arg);
} else if (strcasecmp(word, "passive") == 0) {
if (none ||
(!EMPTYSTR(arg) && strcasecmp(arg, "off") == 0))
curclass.passive = 0;
else
curclass.passive = 1;
} else if (strcasecmp(word, "portrange") == 0) {
int minport, maxport;
char *min, *max;
if (none) {
curclass.portmin = 0;
curclass.portmax = 0;
continue;
}
if (EMPTYSTR(arg))
continue;
min = arg;
NEXTWORD(p, max);
if (EMPTYSTR(max)) {
syslog(LOG_WARNING,
"%s line %d: missing maxport argument",
infile, (int)line);
continue;
}
minport = (int)strtol(min, &endp, 10);
if (*endp != 0 || minport < IPPORT_RESERVED ||
minport > IPPORT_ANONMAX) {
syslog(LOG_WARNING,
"%s line %d: invalid minport %s",
infile, (int)line, min);
continue;
}
maxport = (int)strtol(max, &endp, 10);
if (*endp != 0 || maxport < IPPORT_RESERVED ||
maxport > IPPORT_ANONMAX) {
syslog(LOG_WARNING,
"%s line %d: invalid maxport %s",
infile, (int)line, max);
continue;
}
if (minport >= maxport) {
syslog(LOG_WARNING,
"%s line %d: minport %d >= maxport %d",
infile, (int)line, minport, maxport);
continue;
}
curclass.portmin = minport;
curclass.portmax = maxport;
} else if (strcasecmp(word, "rateget") == 0) {
if (none || EMPTYSTR(arg))
continue;
rate = strsuftoi(arg);
if (rate == -1) {
syslog(LOG_WARNING,
"%s line %d: invalid rateget %s",
infile, (int)line, arg);
continue;
}
curclass.maxrateget = rate;
curclass.rateget = rate;
} else if (strcasecmp(word, "rateput") == 0) {
if (none || EMPTYSTR(arg))
continue;
rate = strsuftoi(arg);
if (rate == -1) {
syslog(LOG_WARNING,
"%s line %d: invalid rateput %s",
infile, (int)line, arg);
continue;
}
curclass.maxrateput = rate;
curclass.rateput = rate;
} else if (strcasecmp(word, "timeout") == 0) {
if (none || EMPTYSTR(arg))
continue;
timeout = (unsigned int)strtoul(arg, &endp, 10);
if (*endp != 0) {
syslog(LOG_WARNING,
"%s line %d: invalid timeout %s",
infile, (int)line, arg);
continue;
}
if (timeout < 30) {
syslog(LOG_WARNING,
"%s line %d: timeout %d < 30 seconds",
infile, (int)line, timeout);
continue;
}
if (timeout > curclass.maxtimeout) {
syslog(LOG_WARNING,
"%s line %d: timeout %d > maxtimeout (%d)",
infile, (int)line, timeout,
curclass.maxtimeout);
continue;
}
curclass.timeout = timeout;
} else if (strcasecmp(word, "template") == 0) {
if (none)
continue;
REASSIGN(template, EMPTYSTR(arg) ? NULL : xstrdup(arg));
} else if (strcasecmp(word, "umask") == 0) {
mode_t umask;
if (none || EMPTYSTR(arg))
continue;
umask = (mode_t)strtoul(arg, &endp, 8);
if (*endp != 0 || umask > 0777) {
syslog(LOG_WARNING,
"%s line %d: invalid umask %s",
infile, (int)line, arg);
continue;
}
curclass.umask = umask;
} else if (strcasecmp(word, "upload") == 0) {
if (none ||
(!EMPTYSTR(arg) && strcasecmp(arg, "off") == 0)) {
curclass.modify = 0;
curclass.upload = 0;
} else
curclass.upload = 1;
} else {
syslog(LOG_WARNING,
"%s line %d: unknown directive '%s'",
infile, (int)line, word);
continue;
}
}
REASSIGN(template, NULL);
fclose(f);
}
/*
* Show file listed in curclass.display first time in, and list all the
* files named in curclass.notify in the current directory. Send back
* responses with the prefix `code' + "-".
*/
void
show_chdir_messages(int code)
{
static StringList *slist = NULL;
struct stat st;
struct tm *t;
glob_t gl;
time_t now, then;
int age;
char cwd[MAXPATHLEN];
char *cp, **rlist;
if (quietmessages)
return;
/* Setup list for directory cache */
if (slist == NULL)
slist = sl_init();
if (slist == NULL) {
syslog(LOG_WARNING, "can't allocate memory for stringlist");
return;
}
/* Check if this directory has already been visited */
if (getcwd(cwd, sizeof(cwd) - 1) == NULL) {
syslog(LOG_WARNING, "can't getcwd: %s", strerror(errno));
return;
}
if (sl_find(slist, cwd) != NULL)
return;
cp = xstrdup(cwd);
if (sl_add(slist, cp) == -1)
syslog(LOG_WARNING, "can't add `%s' to stringlist", cp);
/* First check for a display file */
(void)format_file(curclass.display, code);
/* Now see if there are any notify files */
if (EMPTYSTR(curclass.notify))
return;
if (glob(curclass.notify, 0, NULL, &gl) != 0 || gl.gl_matchc == 0)
return;
time(&now);
for (rlist = gl.gl_pathv; *rlist != NULL; rlist++) {
if (stat(*rlist, &st) != 0)
continue;
if (!S_ISREG(st.st_mode))
continue;
then = st.st_mtime;
if (code != 0) {
reply(-code, "%s", "");
code = 0;
}
reply(-code, "Please read the file %s", *rlist);
t = localtime(&now);
age = 365 * t->tm_year + t->tm_yday;
t = localtime(&then);
age -= 365 * t->tm_year + t->tm_yday;
reply(-code, " it was last modified on %.24s - %d day%s ago",
ctime(&then), age, PLURAL(age));
}
globfree(&gl);
}
int
format_file(const char *file, int code)
{
FILE *f;
char *buf, *p, *cwd;
size_t len;
time_t now;
if (quietmessages)
return (0);
if (EMPTYSTR(file))
return(0);
if ((f = fopen(file, "r")) == NULL)
return (0);
reply(-code, "%s", "");
for (;
(buf = fparseln(f, &len, NULL, "\0\0\0", 0)) != NULL; free(buf)) {
if (len > 0)
if (buf[len - 1] == '\n')
buf[--len] = '\0';
cprintf(stdout, " ");
for (p = buf; *p; p++) {
if (*p == '%') {
p++;
switch (*p) {
case 'c':
cprintf(stdout, "%s",
curclass.classname ?
curclass.classname : "<unknown>");
break;
case 'C':
if (getcwd(cwd, sizeof(cwd)-1) == NULL){
syslog(LOG_WARNING,
"can't getcwd: %s",
strerror(errno));
continue;
}
cprintf(stdout, "%s", cwd);
break;
case 'E':
/* XXXX email address */
break;
case 'L':
cprintf(stdout, "%s", hostname);
break;
case 'M':
if (curclass.limit == -1)
cprintf(stdout, "unlimited");
else
cprintf(stdout, "%d",
curclass.limit);
break;
case 'N':
if (connections > 0)
cprintf(stdout, "%d",
connections);
break;
case 'R':
cprintf(stdout, "%s", remotehost);
break;
case 'T':
now = time(NULL);
cprintf(stdout, "%.24s", ctime(&now));
break;
case 'U':
cprintf(stdout, "%s",
pw ? pw->pw_name : "<unknown>");
break;
case '%':
CPUTC('%', stdout);
break;
}
} else
CPUTC(*p, stdout);
}
cprintf(stdout, "\r\n");
}
(void)fflush(stdout);
(void)fclose(f);
return (1);
}
/*
* Find s2 at the end of s1. If found, return a string up to (but
* not including) s2, otherwise returns NULL.
*/
static char *
strend(const char *s1, char *s2)
{
static char buf[MAXPATHLEN];
char *start;
size_t l1, l2;
l1 = strlen(s1);
l2 = strlen(s2);
if (l2 >= l1)
return(NULL);
strlcpy(buf, s1, sizeof(buf));
start = buf + (l1 - l2);
if (strcmp(start, s2) == 0) {
*start = '\0';
return(buf);
} else
return(NULL);
}
static int
filetypematch(char *types, int mode)
{
for ( ; types[0] != '\0'; types++)
switch (*types) {
case 'd':
if (S_ISDIR(mode))
return(1);
break;
case 'f':
if (S_ISREG(mode))
return(1);
break;
}
return(0);
}
/*
* Look for a conversion. If we succeed, return a pointer to the
* command to execute for the conversion.
*
* The command is stored in a static array so there's no memory
* leak problems, and not too much to change in ftpd.c. This
* routine doesn't need to be re-entrant unless we start using a
* multi-threaded ftpd, and that's not likely for a while...
*/
char **
do_conversion(const char *fname)
{
struct ftpconv *cp;
struct stat st;
int o_errno;
char *base = NULL;
char *cmd, *p, *lp, **argv;
StringList *sl;
o_errno = errno;
sl = NULL;
cmd = NULL;
for (cp = curclass.conversions; cp != NULL; cp = cp->next) {
if (cp->suffix == NULL) {
syslog(LOG_WARNING,
"cp->suffix==NULL in conv list; SHOULDN'T HAPPEN!");
continue;
}
if ((base = strend(fname, cp->suffix)) == NULL)
continue;
if (cp->types == NULL || cp->disable == NULL ||
cp->command == NULL)
continue;
/* Is it enabled? */
if (strcmp(cp->disable, ".") != 0 &&
stat(cp->disable, &st) == 0)
continue;
/* Does the base exist? */
if (stat(base, &st) < 0)
continue;
/* Is the file type ok */
if (!filetypematch(cp->types, st.st_mode))
continue;
break; /* "We have a winner!" */
}
/* If we got through the list, no conversion */
if (cp == NULL)
goto cleanup_do_conv;
/* Split up command into an argv */
if ((sl = sl_init()) == NULL)
goto cleanup_do_conv;
cmd = xstrdup(cp->command);
p = cmd;
while (p) {
NEXTWORD(p, lp);
if (strcmp(lp, "%s") == 0)
lp = base;
if (sl_add(sl, xstrdup(lp)) == -1)
goto cleanup_do_conv;
}
if (sl_add(sl, NULL) == -1)
goto cleanup_do_conv;
argv = sl->sl_str;
free(cmd);
free(sl);
return(argv);
cleanup_do_conv:
if (sl)
sl_free(sl, 1);
free(cmd);
errno = o_errno;
return(NULL);
}
/*
* Convert the string `arg' to an int, which may have an optional SI suffix
* (`b', `k', `m', `g'). Returns the number for success, -1 otherwise.
*/
int
strsuftoi(const char *arg)
{
char *cp;
long val;
if (!isdigit((unsigned char)arg[0]))
return (-1);
val = strtol(arg, &cp, 10);
if (cp != NULL) {
if (cp[0] != '\0' && cp[1] != '\0')
return (-1);
switch (tolower((unsigned char)cp[0])) {
case '\0':
case 'b':
break;
case 'k':
val <<= 10;
break;
case 'm':
val <<= 20;
break;
case 'g':
val <<= 30;
break;
default:
return (-1);
}
}
if (val < 0 || val > INT_MAX)
return (-1);
return (val);
}
/*
* Count the number of current connections, reading from
* /var/run/ftpd.pids-<class>
* Does a kill -0 on each pid in that file, and only counts
* processes that exist (or frees the slot if it doesn't).
* Adds getpid() to the first free slot. Truncates the file
* if possible.
*/
void
count_users(void)
{
char fn[MAXPATHLEN];
int fd, i, last;
size_t count;
pid_t *pids, mypid;
struct stat sb;
(void)strlcpy(fn, _PATH_CLASSPIDS, sizeof(fn));
(void)strlcat(fn, curclass.classname, sizeof(fn));
pids = NULL;
connections = 1;
if ((fd = open(fn, O_RDWR | O_CREAT | O_EXLOCK, 0600)) == -1)
return;
if (fstat(fd, &sb) == -1)
goto cleanup_count;
if ((pids = malloc(sb.st_size + sizeof(pid_t))) == NULL)
goto cleanup_count;
count = read(fd, pids, sb.st_size);
if (count < 0 || count != sb.st_size)
goto cleanup_count;
count /= sizeof(pid_t);
mypid = getpid();
last = 0;
for (i = 0; i < count; i++) {
if (pids[i] == 0)
continue;
if (kill(pids[i], 0) == -1 && errno != EPERM) {
if (mypid != 0) {
pids[i] = mypid;
mypid = 0;
last = i;
}
} else {
connections++;
last = i;
}
}
if (mypid != 0) {
if (pids[last] != 0)
last++;
pids[last] = mypid;
}
count = (last + 1) * sizeof(pid_t);
if (lseek(fd, 0, SEEK_SET) == -1)
goto cleanup_count;
if (write(fd, pids, count) == -1)
goto cleanup_count;
(void)ftruncate(fd, count);
cleanup_count:
(void)flock(fd, LOCK_UN);
close(fd);
REASSIGN(pids, NULL);
}