/*
conf.c -- configuration code
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>
+ 1998-2001 Ivo Timmermans <itimmermans@bigfoot.com>
+ 2000,2001 Guus Sliepen <guus@sliepen.warande.net>
+ 2000 Cris van Pelt <tribbel@arise.dhs.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: conf.c,v 1.9.4.26 2000/11/29 14:30:07 zarq Exp $
+ $Id: conf.c,v 1.9.4.44 2001/10/10 20:34:27 guus Exp $
*/
#include "config.h"
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <string.h>
#include <xalloc.h>
#include <utils.h> /* for cp */
+#include <avl_tree.h>
#include "conf.h"
#include "netutl.h" /* for strtoip */
#include "system.h"
-config_t *config = NULL;
+avl_tree_t *config_tree;
+
int debug_lvl = 0;
int timeout = 0; /* seconds before timeout */
char *confbase = NULL; /* directory in which all config files are */
/* 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[] = {
-/* Main configuration file keywords */
- { "Name", config_name, TYPE_NAME },
- { "ConnectTo", config_connectto, TYPE_NAME },
- { "PingTimeout", config_pingtimeout, TYPE_INT },
- { "TapDevice", config_tapdevice, TYPE_NAME },
- { "PrivateKey", config_privatekey, TYPE_NAME },
- { "KeyExpire", config_keyexpire, TYPE_INT },
- { "Hostnames", config_hostnames, TYPE_BOOL },
- { "Interface", config_interface, TYPE_NAME },
- { "InterfaceIP", config_interfaceip, TYPE_IP },
-/* Host configuration file keywords */
- { "Address", config_address, TYPE_NAME },
- { "Port", config_port, TYPE_INT },
- { "PublicKey", config_publickey, TYPE_NAME },
- { "Subnet", config_subnet, TYPE_IP }, /* Use IPv4 subnets only for now */
- { "RestrictHosts", config_restricthosts, TYPE_BOOL },
- { "RestrictSubnets", config_restrictsubnets, TYPE_BOOL },
- { "RestrictAddress", config_restrictaddress, TYPE_BOOL },
- { "RestrictPort", config_restrictport, TYPE_BOOL },
- { "IndirectData", config_indirectdata, TYPE_BOOL },
- { "TCPonly", config_tcponly, TYPE_BOOL },
- { NULL, 0, 0 }
-};
+int config_compare(config_t *a, config_t *b)
+{
+ int result;
+
+ result = strcmp(a->variable, b->variable);
+
+ if(result)
+ return result;
-/*
- Add given value to the list of configs cfg
-*/
-config_t *
-add_config_val(config_t **cfg, int argtype, char *val)
+ result = a->line - b->line;
+
+ if(result)
+ return result;
+ else
+ return strcmp(a->file, b->file);
+}
+
+void init_configuration(avl_tree_t **config_tree)
{
- config_t *p;
- char *q;
cp
- p = (config_t*)xmalloc(sizeof(*p));
- p->data.val = 0;
+ *config_tree = avl_alloc_tree((avl_compare_t)config_compare, (avl_action_t)free_config);
+cp
+}
- switch(argtype)
- {
- case TYPE_INT:
- p->data.val = strtol(val, &q, 0);
- if(q && *q)
- p->data.val = 0;
- break;
- case TYPE_NAME:
- p->data.ptr = xmalloc(strlen(val) + 1);
- strcpy(p->data.ptr, val);
- break;
- case TYPE_IP:
- p->data.ip = strtoip(val);
- break;
- case TYPE_BOOL:
- if(!strcasecmp("yes", val))
- p->data.val = stupid_true;
- else if(!strcasecmp("no", val))
- p->data.val = stupid_false;
- else
- p->data.val = 0;
- }
+void exit_configuration(avl_tree_t **config_tree)
+{
+cp
+ avl_delete_tree(*config_tree);
+ *config_tree = NULL;
+cp
+}
- p->argtype = argtype;
+config_t *new_config(void)
+{
+ config_t *cfg;
+cp
+ cfg = (config_t *)xmalloc_and_zero(sizeof(*cfg));
+
+ return cfg;
+}
+
+void free_config(config_t *cfg)
+{
+cp
+ if(cfg->variable)
+ free(cfg->variable);
+ if(cfg->value)
+ free(cfg->value);
+ if(cfg->file)
+ free(cfg->file);
+ free(cfg);
+cp
+}
- if(p->data.val)
+void config_add(avl_tree_t *config_tree, config_t *cfg)
+{
+cp
+ avl_insert(config_tree, cfg);
+cp
+}
+
+config_t *lookup_config(avl_tree_t *config_tree, char *variable)
+{
+ config_t cfg, *found;
+cp
+ cfg.variable = variable;
+ cfg.file = "";
+ cfg.line = 0;
+
+ found = avl_search_closest_greater(config_tree, &cfg);
+
+ if(!strcmp(found->variable, variable))
+ return found;
+ else
+ return NULL;
+}
+
+config_t *lookup_config_next(avl_tree_t *config_tree, config_t *cfg)
+{
+ avl_node_t *node;
+ config_t *found;
+cp
+ node = avl_search_node(config_tree, cfg);
+
+ if(node)
{
- p->next = *cfg;
- *cfg = p;
+ if(node->next)
+ {
+ found = (config_t *)node->next->data;
+ if(!strcmp(found->variable, cfg->variable))
+ return found;
+ }
+ }
+
+ return NULL;
+}
+
+int get_config_bool(config_t *cfg, int *result)
+{
cp
- return p;
+ if(!cfg)
+ return 0;
+
+ if(!strcasecmp(cfg->value, "yes"))
+ {
+ *result = 1;
+ return 1;
}
- else
+ else if(!strcasecmp(cfg->value, "np"))
{
- free(p);
+ *result = 0;
+ return 1;
+ }
+
+ syslog(LOG_ERR, _("\"yes\" or \"no\" expected for configuration variable %s in %s line %d"),
+ cfg->value, cfg->file, cfg->line);
+
+ return 0;
+}
+
+int get_config_int(config_t *cfg, int *result)
+{
cp
- return NULL;
+ if(!cfg)
+ return 0;
+
+ if(sscanf(cfg->value, "%d", result) == 1)
+ return 1;
+
+ syslog(LOG_ERR, _("Integer expected for configuration variable %s in %s line %d"),
+ cfg->value, cfg->file, cfg->line);
+ return 0;
+}
+
+int get_config_string(config_t *cfg, char **result)
+{
+cp
+ if(!cfg)
+ return 0;
+
+ *result = cfg->value;
+ return 1;
+}
+
+int get_config_ip(config_t *cfg, ip_mask_t **result)
+{
+ ip_mask_t *ip;
+cp
+ if(!cfg)
+ return 0;
+
+ ip = strtoip(cfg->value);
+
+ if(ip)
+ {
+ *result = ip;
+ return 1;
}
+
+ syslog(LOG_ERR, _("IP address expected for configuration variable %s in %s line %d"),
+ cfg->value, cfg->file, cfg->line);
+ return 0;
}
/*
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 *readline(FILE *fp, char **buf, size_t *buflen)
{
char *newline = NULL;
char *p;
if(feof(fp))
return NULL;
-
- size = 100;
+
+ if((buf != NULL) && (buflen != NULL))
+ {
+ size = *buflen;
+ line = *buf;
+ }
+ else
+ {
+ size = 100;
+ line = xmalloc(size);
+ }
+
maxlen = size;
- line = xmalloc(size);
idx = line;
+ *idx = 0;
for(;;)
{
errno = 0;
}
}
+ if((buf != NULL) && (buflen != NULL))
+ {
+ *buflen = size;
+ *buf = line;
+ }
return line;
}
Parse a configuration file and put the results in the configuration tree
starting at *base.
*/
-int read_config_file(config_t **base, const char *fname)
+int read_config_file(avl_tree_t *config_tree, const char *fname)
{
- int err = -1;
+ int err = -2; /* Parse error */
FILE *fp;
- char *line;
- char *p, *q;
- int i, lineno = 0;
+ char *buffer, *line;
+ char *variable, *value;
+ int lineno = 0, ignore = 0;
config_t *cfg;
+ size_t bufsize;
+
cp
if((fp = fopen (fname, "r")) == NULL)
{
- return -1;
+ syslog(LOG_ERR, _("Cannot open config file %s: %m"), fname);
+ return -3;
}
+ bufsize = 100;
+ buffer = xmalloc(bufsize);
+
for(;;)
{
- if((line = readline(fp)) == NULL)
+ if((line = readline(fp, &buffer, &bufsize)) == NULL)
{
err = -1;
break;
}
-
- lineno++;
-
- if((p = strtok(line, "\t =")) == NULL)
- continue; /* no tokens on this line */
- if(p[0] == '#')
- continue; /* comment: ignore */
-
- for(i = 0; hazahaza[i].name != NULL; i++)
- if(!strcasecmp(hazahaza[i].name, p))
- break;
-
- if(!hazahaza[i].name)
- {
- syslog(LOG_ERR, _("Invalid variable name on line %d while reading config file %s"),
- lineno, fname);
- break;
- }
-
- if(((q = strtok(NULL, "\t\n\r =")) == NULL) || q[0] == '#')
+ if(feof(fp))
{
- fprintf(stderr, _("No value for variable on line %d while reading config file %s"),
- lineno, fname);
+ err = 0;
break;
}
- cfg = add_config_val(base, hazahaza[i].argtype, q);
- if(cfg == NULL)
- {
- fprintf(stderr, _("Invalid value for variable on line %d while reading config file %s"),
- lineno, fname);
- break;
- }
+ lineno++;
+
+ if((variable = strtok(line, "\t =")) == NULL)
+ continue; /* no tokens on this line */
- cfg->which = hazahaza[i].which;
- if(!config)
- config = cfg;
- free(line);
+ if(variable[0] == '#')
+ continue; /* comment: ignore */
+
+ if(!strcmp(variable, "-----BEGIN"))
+ ignore = 1;
+
+ if(!ignore)
+ {
+ if(((value = strtok(NULL, "\t\n\r =")) == NULL) || value[0] == '#')
+ {
+ syslog(LOG_ERR, _("No value for variable `%s' on line %d while reading config file %s"),
+ variable, lineno, fname);
+ break;
+ }
+
+ cfg = new_config();
+ cfg->variable = xstrdup(variable);
+ cfg->value = xstrdup(value);
+ cfg->file = xstrdup(fname);
+ cfg->line = lineno;
+
+ config_add(config_tree, cfg);
+ }
+
+ if(!strcmp(variable, "-----END"))
+ ignore = 0;
}
- free(line);
+ free(buffer);
fclose (fp);
cp
return err;
int x;
cp
asprintf(&fname, "%s/tinc.conf", confbase);
- x = read_config_file(&config, fname);
- if(x != 0)
+ x = read_config_file(config_tree, fname);
+ if(x == -1) /* System error: complain */
{
- fprintf(stderr, _("Failed to read `%s': %m\n"),
+ syslog(LOG_ERR, _("Failed to read `%s': %m"),
fname);
}
free(fname);
return x;
}
-/*
- Look up the value of the config option type
-*/
-const config_t *get_config_val(config_t *p, which_t type)
+int isadir(const char* f)
{
-cp
- for(; p != NULL; p = p->next)
- if(p->which == type)
- break;
-cp
- return p;
+ struct stat s;
+
+ if(stat(f, &s) < 0)
+ return 0;
+ else
+ return S_ISDIR(s.st_mode);
}
-/*
- Remove the complete configuration tree.
-*/
-void clear_config(config_t **base)
+int is_safe_path(const char *file)
{
- config_t *p, *next;
-cp
- for(p = *base; p != NULL; p = next)
+ char *p;
+ const char *f;
+ char x;
+ struct stat s;
+ char l[MAXBUFSIZE];
+
+ if(*file != '/')
+ {
+ syslog(LOG_ERR, _("`%s' is not an absolute path"), file);
+ return 0;
+ }
+
+ p = strrchr(file, '/');
+
+ if(p == file) /* It's in the root */
+ p++;
+
+ x = *p;
+ *p = '\0';
+
+ f = file;
+check1:
+ if(lstat(f, &s) < 0)
+ {
+ syslog(LOG_ERR, _("Couldn't stat `%s': %m"),
+ f);
+ return 0;
+ }
+
+ if(s.st_uid != geteuid())
{
- next = p->next;
- if(p->data.ptr && (p->argtype == TYPE_NAME))
+ syslog(LOG_ERR, _("`%s' is owned by UID %d instead of %d"),
+ f, s.st_uid, geteuid());
+ return 0;
+ }
+
+ if(S_ISLNK(s.st_mode))
+ {
+ syslog(LOG_WARNING, _("Warning: `%s' is a symlink"),
+ f);
+
+ if(readlink(f, l, MAXBUFSIZE) < 0)
{
- free(p->data.ptr);
+ syslog(LOG_ERR, _("Unable to read symbolic link `%s': %m"), f);
+ return 0;
}
- free(p);
+
+ f = l;
+ goto check1;
+ }
+
+ *p = x;
+ f = file;
+
+check2:
+ if(lstat(f, &s) < 0 && errno != ENOENT)
+ {
+ syslog(LOG_ERR, _("Couldn't stat `%s': %m"),
+ f);
+ return 0;
+ }
+
+ if(errno == ENOENT)
+ return 1;
+
+ if(s.st_uid != geteuid())
+ {
+ syslog(LOG_ERR, _("`%s' is owned by UID %d instead of %d"),
+ f, s.st_uid, geteuid());
+ return 0;
+ }
+
+ if(S_ISLNK(s.st_mode))
+ {
+ syslog(LOG_WARNING, _("Warning: `%s' is a symlink"),
+ f);
+
+ if(readlink(f, l, MAXBUFSIZE) < 0)
+ {
+ syslog(LOG_ERR, _("Unable to read symbolic link `%s': %m"), f);
+ return 0;
+ }
+
+ f = l;
+ goto check2;
}
- *base = NULL;
-cp
-}
-#define is_safe_file(p) 1
+ if(s.st_mode & 0007)
+ {
+ /* Accessible by others */
+ syslog(LOG_ERR, _("`%s' has unsecure permissions"),
+ f);
+ return 0;
+ }
+
+ return 1;
+}
-FILE *ask_and_safe_open(const char* filename, const char* what)
+FILE *ask_and_safe_open(const char* filename, const char* what, const char* mode)
{
FILE *r;
char *directory;
char *fn;
- int len;
/* Check stdin and stdout */
if(!isatty(0) || !isatty(1))
/* 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)
+ fflush(stdout);
+
+ if((fn = readline(stdin, NULL, NULL)) == NULL)
{
- fprintf(stderr, _("Error while reading stdin: %m\n"));
+ fprintf(stderr, _("Error while reading stdin: %s\n"), strerror(errno));
return NULL;
}
+
if(strlen(fn) == 0)
/* User just pressed enter. */
fn = xstrdup(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);
+ asprintf(&p, "%s/%s", directory, fn);
free(fn);
+ free(directory);
fn = p;
}
- if(!is_safe_file(fn))
+ umask(0077); /* Disallow everything for group and other */
+
+ /* Open it first to keep the inode busy */
+ if((r = fopen(fn, mode)) == NULL)
+ {
+ fprintf(stderr, _("Error opening file `%s': %s\n"),
+ fn, strerror(errno));
+ 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;
}
- if((r = fopen(fn, "w")) == NULL)
- {
- fprintf(stderr, _("Error opening file `%s': %m\n"),
- fn);
- }
-
free(fn);
- free(directory);
-
+
return r;
}
projects / tinc / blobdiff