tinc/src/conf.c
2013-01-20 21:03:22 +01:00

415 lines
9.1 KiB
C

/*
conf.c -- configuration code
Copyright (C) 1998 Robert van der Meulen
1998-2005 Ivo Timmermans
2000-2013 Guus Sliepen <guus@tinc-vpn.org>
2010-2011 Julien Muchembled <jm@jmuchemb.eu>
2000 Cris van Pelt
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
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "system.h"
#include "splay_tree.h"
#include "connection.h"
#include "conf.h"
#include "list.h"
#include "logger.h"
#include "names.h"
#include "netutl.h" /* for str2address */
#include "protocol.h"
#include "utils.h" /* for cp */
#include "xalloc.h"
splay_tree_t *config_tree;
int pinginterval = 0; /* seconds between pings */
int pingtimeout = 0; /* seconds to wait for response */
list_t *cmdline_conf = NULL; /* global/host configuration values given at the command line */
static int config_compare(const config_t *a, const config_t *b) {
int result;
result = strcasecmp(a->variable, b->variable);
if(result)
return result;
/* give priority to command line options */
result = !b->file - !a->file;
if (result)
return result;
result = a->line - b->line;
if(result)
return result;
else
return a->file ? strcmp(a->file, b->file) : 0;
}
void init_configuration(splay_tree_t ** config_tree) {
*config_tree = splay_alloc_tree((splay_compare_t) config_compare, (splay_action_t) free_config);
}
void exit_configuration(splay_tree_t ** config_tree) {
splay_delete_tree(*config_tree);
*config_tree = NULL;
}
config_t *new_config(void) {
return xmalloc_and_zero(sizeof(config_t));
}
void free_config(config_t *cfg) {
if(cfg->variable)
free(cfg->variable);
if(cfg->value)
free(cfg->value);
if(cfg->file)
free(cfg->file);
free(cfg);
}
void config_add(splay_tree_t *config_tree, config_t *cfg) {
splay_insert(config_tree, cfg);
}
config_t *lookup_config(splay_tree_t *config_tree, char *variable) {
config_t cfg, *found;
cfg.variable = variable;
cfg.file = NULL;
cfg.line = 0;
found = splay_search_closest_greater(config_tree, &cfg);
if(!found)
return NULL;
if(strcasecmp(found->variable, variable))
return NULL;
return found;
}
config_t *lookup_config_next(splay_tree_t *config_tree, const config_t *cfg) {
splay_node_t *node;
config_t *found;
node = splay_search_node(config_tree, cfg);
if(node) {
if(node->next) {
found = node->next->data;
if(!strcasecmp(found->variable, cfg->variable))
return found;
}
}
return NULL;
}
bool get_config_bool(const config_t *cfg, bool *result) {
if(!cfg)
return false;
if(!strcasecmp(cfg->value, "yes")) {
*result = true;
return true;
} else if(!strcasecmp(cfg->value, "no")) {
*result = false;
return true;
}
logger(DEBUG_ALWAYS, LOG_ERR, "\"yes\" or \"no\" expected for configuration variable %s in %s line %d",
cfg->variable, cfg->file, cfg->line);
return false;
}
bool get_config_int(const config_t *cfg, int *result) {
if(!cfg)
return false;
if(sscanf(cfg->value, "%d", result) == 1)
return true;
logger(DEBUG_ALWAYS, LOG_ERR, "Integer expected for configuration variable %s in %s line %d",
cfg->variable, cfg->file, cfg->line);
return false;
}
bool get_config_string(const config_t *cfg, char **result) {
if(!cfg)
return false;
*result = xstrdup(cfg->value);
return true;
}
bool get_config_address(const config_t *cfg, struct addrinfo **result) {
struct addrinfo *ai;
if(!cfg)
return false;
ai = str2addrinfo(cfg->value, NULL, 0);
if(ai) {
*result = ai;
return true;
}
logger(DEBUG_ALWAYS, LOG_ERR, "Hostname or IP address expected for configuration variable %s in %s line %d",
cfg->variable, cfg->file, cfg->line);
return false;
}
bool get_config_subnet(const config_t *cfg, subnet_t ** result) {
subnet_t subnet = {NULL};
if(!cfg)
return false;
if(!str2net(&subnet, cfg->value)) {
logger(DEBUG_ALWAYS, LOG_ERR, "Subnet expected for configuration variable %s in %s line %d",
cfg->variable, cfg->file, cfg->line);
return false;
}
/* Teach newbies what subnets are... */
if(((subnet.type == SUBNET_IPV4)
&& !maskcheck(&subnet.net.ipv4.address, subnet.net.ipv4.prefixlength, sizeof subnet.net.ipv4.address))
|| ((subnet.type == SUBNET_IPV6)
&& !maskcheck(&subnet.net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof subnet.net.ipv6.address))) {
logger(DEBUG_ALWAYS, LOG_ERR, "Network address and prefix length do not match for configuration variable %s in %s line %d",
cfg->variable, cfg->file, cfg->line);
return false;
}
*(*result = new_subnet()) = subnet;
return true;
}
/*
Read exactly one line and strip the trailing newline if any.
*/
static char *readline(FILE * fp, char *buf, size_t buflen) {
char *newline = NULL;
char *p;
if(feof(fp))
return NULL;
p = fgets(buf, buflen, fp);
if(!p)
return NULL;
newline = strchr(p, '\n');
if(!newline)
return buf;
/* kill newline and carriage return if necessary */
*newline = '\0';
if(newline > p && newline[-1] == '\r')
newline[-1] = '\0';
return buf;
}
config_t *parse_config_line(char *line, const char *fname, int lineno) {
config_t *cfg;
int len;
char *variable, *value, *eol;
variable = value = line;
eol = line + strlen(line);
while(strchr("\t ", *--eol))
*eol = '\0';
len = strcspn(value, "\t =");
value += len;
value += strspn(value, "\t ");
if(*value == '=') {
value++;
value += strspn(value, "\t ");
}
variable[len] = '\0';
if(!*value) {
const char err[] = "No value for variable";
if (fname)
logger(DEBUG_ALWAYS, LOG_ERR, "%s `%s' on line %d while reading config file %s",
err, variable, lineno, fname);
else
logger(DEBUG_ALWAYS, LOG_ERR, "%s `%s' in command line option %d",
err, variable, lineno);
return NULL;
}
cfg = new_config();
cfg->variable = xstrdup(variable);
cfg->value = xstrdup(value);
cfg->file = fname ? xstrdup(fname) : NULL;
cfg->line = lineno;
return cfg;
}
/*
Parse a configuration file and put the results in the configuration tree
starting at *base.
*/
bool read_config_file(splay_tree_t *config_tree, const char *fname) {
FILE *fp;
char buffer[MAX_STRING_SIZE];
char *line;
int lineno = 0;
bool ignore = false;
config_t *cfg;
bool result = false;
fp = fopen(fname, "r");
if(!fp) {
logger(DEBUG_ALWAYS, LOG_ERR, "Cannot open config file %s: %s", fname, strerror(errno));
return false;
}
for(;;) {
line = readline(fp, buffer, sizeof buffer);
if(!line) {
if(feof(fp))
result = true;
break;
}
lineno++;
if(!*line || *line == '#')
continue;
if(ignore) {
if(!strncmp(line, "-----END", 8))
ignore = false;
continue;
}
if(!strncmp(line, "-----BEGIN", 10)) {
ignore = true;
continue;
}
cfg = parse_config_line(line, fname, lineno);
if (!cfg)
break;
config_add(config_tree, cfg);
}
fclose(fp);
return result;
}
void read_config_options(splay_tree_t *config_tree, const char *prefix) {
size_t prefix_len = prefix ? strlen(prefix) : 0;
for(const list_node_t *node = cmdline_conf->tail; node; node = node->prev) {
const config_t *cfg = node->data;
config_t *new;
if(!prefix) {
if(strchr(cfg->variable, '.'))
continue;
} else {
if(strncmp(prefix, cfg->variable, prefix_len) ||
cfg->variable[prefix_len] != '.')
continue;
}
new = new_config();
if(prefix)
new->variable = xstrdup(cfg->variable + prefix_len + 1);
else
new->variable = xstrdup(cfg->variable);
new->value = xstrdup(cfg->value);
new->file = NULL;
new->line = cfg->line;
config_add(config_tree, new);
}
}
bool read_server_config(void) {
char *fname;
bool x;
read_config_options(config_tree, NULL);
xasprintf(&fname, "%s" SLASH "tinc.conf", confbase);
x = read_config_file(config_tree, fname);
if(!x)
logger(DEBUG_ALWAYS, LOG_ERR, "Failed to read `%s': %s", fname, strerror(errno));
free(fname);
return x;
}
bool read_host_config(splay_tree_t *config_tree, const char *name) {
char *fname;
bool x;
read_config_options(config_tree, name);
xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, name);
x = read_config_file(config_tree, fname);
free(fname);
return x;
}
bool append_config_file(const char *name, const char *key, const char *value) {
char *fname;
xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, name);
FILE *fp = fopen(fname, "a");
if(!fp) {
logger(DEBUG_ALWAYS, LOG_ERR, "Cannot open config file %s: %s", fname, strerror(errno));
} else {
fprintf(fp, "\n# The following line was automatically added by tinc\n%s = %s\n", key, value);
fclose(fp);
}
free(fname);
return fp != NULL;
}