/*
conf.c -- configuration code
- Copyright (C) 1998 Emphyrio,
+ Copyright (C) 1998 Robert van der Meulen
Copyright (C) 1998,1999,2000 Ivo Timmermans <itimmermans@bigfoot.com>
2000 Guus Sliepen <guus@sliepen.warande.net>
2000 Cris van Pelt <tribbel@arise.dhs.org>
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: conf.c,v 1.9.4.1 2000/06/17 20:55:54 zarq Exp $
+ $Id: conf.c,v 1.9.4.34 2000/12/06 13:33:48 zarq Exp $
*/
-
#include "config.h"
+#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <syslog.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
#include <xalloc.h>
+#include <utils.h> /* for cp */
#include "conf.h"
#include "netutl.h" /* for strtoip */
#include "system.h"
-config_t *config;
+config_t *config = NULL;
int debug_lvl = 0;
int timeout = 0; /* seconds before timeout */
+char *confbase = NULL; /* directory in which all config files are */
+char *netname = NULL; /* name of the vpn network */
-typedef struct internal_config_t {
- char *name;
- enum which_t which;
- int argtype;
-} internal_config_t;
+/* Will be set if HUP signal is received. It will be processed when it is safe. */
+int sighup = 0;
/*
These are all the possible configurable values
*/
static internal_config_t hazahaza[] = {
- { "AllowConnect", allowconnect, TYPE_BOOL }, /* Is not used anywhere. Remove? */
- { "ConnectTo", upstreamip, TYPE_IP },
- { "ConnectPort", upstreamport, TYPE_INT },
- { "ListenPort", listenport, TYPE_INT },
- { "MyOwnVPNIP", myvpnip, TYPE_IP },
- { "MyVirtualIP", myvpnip, TYPE_IP }, /* an alias */
- { "Passphrases", passphrasesdir, TYPE_NAME },
- { "PingTimeout", pingtimeout, TYPE_INT },
- { "TapDevice", tapdevice, TYPE_NAME },
- { "KeyExpire", keyexpire, TYPE_INT },
- { "VpnMask", vpnmask, TYPE_IP },
- { "Hostnames", resolve_dns, TYPE_BOOL },
- { "IndirectData", indirectdata, TYPE_BOOL },
+/* Main configuration file keywords */
+ { "ConnectTo", config_connectto, TYPE_NAME },
+ { "Hostnames", config_hostnames, TYPE_BOOL },
+ { "Interface", config_interface, TYPE_NAME },
+ { "InterfaceIP", config_interfaceip, TYPE_IP },
+ { "KeyExpire", config_keyexpire, TYPE_INT },
+ { "MyVirtualIP", config_dummy, TYPE_IP },
+ { "MyOwnVPNIP", config_dummy, TYPE_IP },
+ { "Name", config_name, TYPE_NAME },
+ { "PingTimeout", config_pingtimeout, TYPE_INT },
+ { "PrivateKey", config_privatekey, TYPE_NAME },
+ { "TapDevice", config_tapdevice, TYPE_NAME },
+ { "VpnMask", config_dummy, TYPE_IP },
+/* Host configuration file keywords */
+ { "Address", config_address, TYPE_NAME },
+ { "IndirectData", config_indirectdata, TYPE_BOOL },
+ { "Port", config_port, TYPE_INT },
+ { "PublicKey", config_publickey, TYPE_NAME },
+ { "RestrictAddress", config_restrictaddress, TYPE_BOOL },
+ { "RestrictHosts", config_restricthosts, TYPE_BOOL },
+ { "RestrictPort", config_restrictport, TYPE_BOOL },
+ { "RestrictSubnets", config_restrictsubnets, TYPE_BOOL },
+ { "Subnet", config_subnet, TYPE_IP }, /* Use IPv4 subnets only for now */
+ { "TCPonly", config_tcponly, TYPE_BOOL },
{ NULL, 0, 0 }
};
{
config_t *p;
char *q;
-
+cp
p = (config_t*)xmalloc(sizeof(*p));
p->data.val = 0;
-
+
switch(argtype)
{
case TYPE_INT:
p->data.val = 0;
}
+ p->argtype = argtype;
+
if(p->data.val)
{
p->next = *cfg;
*cfg = p;
+cp
return p;
}
+ else
+ {
+ free(p);
+cp
+ return NULL;
+ }
+}
+
+/*
+ Read exactly one line and strip the trailing newline if any. If the
+ file was on EOF, return NULL. Otherwise, return all the data in a
+ dynamically allocated buffer.
+
+ If line is non-NULL, it will be used as an initial buffer, to avoid
+ unnecessary mallocing each time this function is called. If buf is
+ given, and buf needs to be expanded, the var pointed to by buflen
+ will be increased.
+*/
+char *readline(FILE *fp, char **buf, size_t *buflen)
+{
+ char *newline = NULL;
+ char *p;
+ char *line; /* The array that contains everything that has been read
+ so far */
+ char *idx; /* Read into this pointer, which points to an offset
+ within line */
+ size_t size, newsize; /* The size of the current array pointed to by
+ line */
+ size_t maxlen; /* Maximum number of characters that may be read with
+ fgets. This is newsize - oldsize. */
+
+ if(feof(fp))
+ return NULL;
+
+ if((buf != NULL) && (buflen != NULL))
+ {
+ size = *buflen;
+ line = *buf;
+ }
+ else
+ {
+ size = 100;
+ line = xmalloc(size);
+ }
+
+ maxlen = size;
+ idx = line;
+ *idx = 0;
+ for(;;)
+ {
+ errno = 0;
+ p = fgets(idx, maxlen, fp);
+ if(p == NULL) /* EOF or error */
+ {
+ if(feof(fp))
+ break;
+
+ /* otherwise: error; let the calling function print an error
+ message if applicable */
+ free(line);
+ return NULL;
+ }
+
+ newline = strchr(p, '\n');
+ if(newline == NULL)
+ /* We haven't yet read everything to the end of the line */
+ {
+ newsize = size << 1;
+ line = xrealloc(line, newsize);
+ idx = &line[size - 1];
+ maxlen = newsize - size + 1;
+ size = newsize;
+ }
+ else
+ {
+ *newline = '\0'; /* kill newline */
+ break; /* yay */
+ }
+ }
- free(p);
- return NULL;
+ if((buf != NULL) && (buflen != NULL))
+ {
+ *buflen = size;
+ *buf = line;
+ }
+ return line;
}
/*
- Get variable from a section in a configfile. returns -1 on failure.
+ Parse a configuration file and put the results in the configuration tree
+ starting at *base.
*/
-int
-readconfig(const char *fname, FILE *fp)
+int read_config_file(config_t **base, const char *fname)
{
- char *line, *temp_buf;
+ int err = -2; /* Parse error */
+ FILE *fp;
+ char *buffer, *line;
char *p, *q;
int i, lineno = 0;
config_t *cfg;
+ size_t bufsize;
+
+cp
+ if((fp = fopen (fname, "r")) == NULL)
+ return -1;
- line = (char *)xmalloc(80 * sizeof(char));
- temp_buf = (char *)xmalloc(80 * sizeof(char));
-
+ bufsize = 100;
+ buffer = xmalloc(bufsize);
+
for(;;)
{
- if(fgets(line, 80, fp) == NULL)
- return 0;
+
+ if((line = readline(fp, &buffer, &bufsize)) == NULL)
+ {
+ err = -1;
+ break;
+ }
+
+ if(feof(fp))
+ {
+ err = 0;
+ break;
+ }
- while(!index(line, '\n'))
- {
- fgets(temp_buf, (strlen(line)+1) * 80, fp);
- if(!temp_buf)
- break;
- strcat(line, temp_buf);
- line = (char *)xrealloc(line, (strlen(line)+1) * sizeof(char));
- }
lineno++;
- if((p = strtok(line, "\t\n\r =")) == NULL)
+ if((p = strtok(line, "\t =")) == NULL)
continue; /* no tokens on this line */
if(p[0] == '#')
if(!hazahaza[i].name)
{
- fprintf(stderr, _("%s: %d: Invalid variable name `%s'.\n"),
- fname, lineno, p);
- return -1;
+ syslog(LOG_ERR, _("Invalid variable name `%s' on line %d while reading config file %s"),
+ p, lineno, fname);
+ break;
}
if(((q = strtok(NULL, "\t\n\r =")) == NULL) || q[0] == '#')
{
- fprintf(stderr, _("%s: %d: No value given for `%s'.\n"),
- fname, lineno, hazahaza[i].name);
- return -1;
+ fprintf(stderr, _("No value for variable `%s' on line %d while reading config file %s"),
+ hazahaza[i].name, lineno, fname);
+ break;
}
- cfg = add_config_val(&config, hazahaza[i].argtype, q);
+ cfg = add_config_val(base, hazahaza[i].argtype, q);
if(cfg == NULL)
{
- fprintf(stderr, _("%s: %d: Invalid value `%s' for variable `%s'.\n"),
- fname, lineno, q, hazahaza[i].name);
- return -1;
+ fprintf(stderr, _("Invalid value for variable `%s' on line %d while reading config file %s"),
+ hazahaza[i].name, lineno, fname);
+ break;
}
cfg->which = hazahaza[i].which;
if(!config)
config = cfg;
}
+
+ free(buffer);
+ fclose (fp);
+cp
+ return err;
+}
+
+int read_server_config()
+{
+ char *fname;
+ int x;
+cp
+ asprintf(&fname, "%s/tinc.conf", confbase);
+ x = read_config_file(&config, fname);
+ if(x == -1) /* System error */
+ {
+ fprintf(stderr, _("Failed to read `%s': %m\n"),
+ fname);
+ }
+ free(fname);
+cp
+ return x;
}
/*
- wrapper function for readconfig
+ Look up the value of the config option type
*/
-int
-read_config_file(const char *fname)
+const config_t *get_config_val(config_t *p, which_t type)
{
- FILE *fp;
+cp
+ for(; p != NULL; p = p->next)
+ if(p->which == type)
+ break;
+cp
+ return p;
+}
- if((fp = fopen (fname, "r")) == NULL)
+/*
+ Remove the complete configuration tree.
+*/
+void clear_config(config_t **base)
+{
+ config_t *p, *next;
+cp
+ for(p = *base; p != NULL; p = next)
{
- fprintf(stderr, _("Could not open %s: %s\n"), fname, sys_errlist[errno]);
- return 1;
+ next = p->next;
+ if(p->data.ptr && (p->argtype == TYPE_NAME))
+ {
+ free(p->data.ptr);
+ }
+ free(p);
}
+ *base = NULL;
+cp
+}
- if(readconfig(fname, fp))
- return -1;
+int isadir(const char* f)
+{
+ struct stat s;
- fclose (fp);
+ if(stat(f, &s) < 0)
+ {
+ fprintf(stderr, _("Couldn't stat `%s': %m\n"),
+ f);
+ return -1;
+ }
- return 0;
+ return S_ISDIR(s.st_mode);
}
-/*
- Look up the value of the config option type
-*/
-const config_t *
-get_config_val(which_t type)
+int is_safe_path(const char *file)
{
- config_t *p;
+ char *p;
+ struct stat s;
- for(p = config; p != NULL; p = p->next)
- if(p->which == type)
- return p;
+ p = strrchr(file, '/');
+ assert(p); /* p has to contain a / */
+ *p = '\0';
+ if(stat(file, &s) < 0)
+ {
+ fprintf(stderr, _("Couldn't stat `%s': %m\n"),
+ file);
+ return 0;
+ }
+ if(s.st_uid != geteuid())
+ {
+ fprintf(stderr, _("`%s' is owned by UID %d instead of %d.\n"),
+ file, s.st_uid, geteuid());
+ return 0;
+ }
+ if(S_ISLNK(s.st_mode))
+ {
+ fprintf(stderr, _("Warning: `%s' is a symlink\n"),
+ file);
+ /* fixme: read the symlink and start again */
+ }
- /* Not found */
- return NULL;
+ *p = '/';
+ if(stat(file, &s) < 0 && errno != ENOENT)
+ {
+ fprintf(stderr, _("Couldn't stat `%s': %m\n"),
+ file);
+ return 0;
+ }
+ if(errno == ENOENT)
+ return 1;
+ if(s.st_uid != geteuid())
+ {
+ fprintf(stderr, _("`%s' is owned by UID %d instead of %d.\n"),
+ file, s.st_uid, geteuid());
+ return 0;
+ }
+ if(S_ISLNK(s.st_mode))
+ {
+ fprintf(stderr, _("Warning: `%s' is a symlink\n"),
+ file);
+ /* fixme: read the symlink and start again */
+ }
+ if(s.st_mode & 0007)
+ {
+ /* Accessible by others */
+ fprintf(stderr, _("`%s' has unsecure permissions.\n"),
+ file);
+ return 0;
+ }
+
+ return 1;
+}
+
+FILE *ask_and_safe_open(const char* filename, const char* what)
+{
+ FILE *r;
+ char *directory;
+ char *fn;
+ int len;
+
+ /* Check stdin and stdout */
+ if(!isatty(0) || !isatty(1))
+ {
+ /* Argh, they are running us from a script or something. Write
+ the files to the current directory and let them burn in hell
+ for ever. */
+ fn = xstrdup(filename);
+ }
+ else
+ {
+ /* Ask for a file and/or directory name. */
+ fprintf(stdout, _("Please enter a file to save %s to [%s]: "),
+ what, filename);
+ fflush(stdout); /* Don't wait for a newline */
+ if((fn = readline(stdin, NULL, NULL)) == NULL)
+ {
+ fprintf(stderr, _("Error while reading stdin: %m\n"));
+ return NULL;
+ }
+ if(strlen(fn) == 0)
+ /* User just pressed enter. */
+ fn = xstrdup(filename);
+ }
+
+ if((strchr(fn, '/') == NULL) || (fn[0] != '/'))
+ {
+ /* The directory is a relative path or a filename. */
+ char *p;
+
+ directory = get_current_dir_name();
+ len = strlen(fn) + strlen(directory) + 2; /* 1 for the / */
+ p = xmalloc(len);
+ snprintf(p, len, "%s/%s", directory, fn);
+ free(fn);
+ free(directory);
+ fn = p;
+ }
+
+ if(isadir(fn) > 0) /* -1 is error */
+ {
+ char *p;
+
+ len = strlen(fn) + strlen(filename) + 2; /* 1 for the / */
+ p = xmalloc(len);
+ snprintf(p, len, "%s/%s", fn, filename);
+ free(fn);
+ fn = p;
+ }
+
+ umask(0077); /* Disallow everything for group and other */
+
+ /* Open it first to keep the inode busy */
+ if((r = fopen(fn, "w")) == NULL)
+ {
+ fprintf(stderr, _("Error opening file `%s': %m\n"),
+ fn);
+ free(fn);
+ return NULL;
+ }
+
+ /* Then check the file for nasty attacks */
+ if(!is_safe_path(fn)) /* Do not permit any directories that are
+ readable or writeable by other users. */
+ {
+ fprintf(stderr, _("The file `%s' (or any of the leading directories) has unsafe permissions.\n"
+ "I will not create or overwrite this file.\n"),
+ fn);
+ fclose(r);
+ free(fn);
+ return NULL;
+ }
+
+ free(fn);
+
+ return r;
}
projects / tinc / blobdiff