/*
conf.c -- configuration code
- Copyright (C) 1998 Emphyrio,
- Copyright (C) 1998,1999,2000 Ivo Timmermans <zarq@iname.com>
+ Copyright (C) 1998 Robert van der Meulen
+ 1998-2002 Ivo Timmermans <itimmermans@bigfoot.com>
+ 2000-2002 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
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., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-/* Created more dynamic storage for lines read from the config file. --
- Cris van Pelt */
+ $Id: conf.c,v 1.9.4.54 2002/03/24 17:14:01 guus Exp $
+*/
#include "config.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 <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 "netutl.h" /* for str2address */
+
+#include "system.h"
+
+avl_tree_t *config_tree;
-config_t *config;
int debug_lvl = 0;
-int timeout = 0; /* seconds before timeout */
+int pingtimeout = 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;
+int config_compare(config_t *a, config_t *b)
+{
+ int result;
-/*
- 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 },
- { NULL, 0, 0 }
-};
+ result = strcasecmp(a->variable, b->variable);
-/*
- Add given value to the list of configs cfg
-*/
-config_t *
-add_config_val(config_t **cfg, int argtype, char *val)
-{
- config_t *p;
- char *q;
-
- p = (config_t*)xmalloc(sizeof(*p));
- p->data.val = 0;
-
- 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;
- }
+ if(result)
+ return result;
+
+ result = a->line - b->line;
+
+ if(result)
+ return result;
+ else
+ return strcmp(a->file, b->file);
+}
+
+void init_configuration(avl_tree_t **config_tree)
+{
+cp
+ *config_tree = avl_alloc_tree((avl_compare_t)config_compare, (avl_action_t)free_config);
+cp
+}
+
+void exit_configuration(avl_tree_t **config_tree)
+{
+cp
+ avl_delete_tree(*config_tree);
+ *config_tree = NULL;
+cp
+}
+
+config_t *new_config(void)
+{
+ config_t *cfg;
+cp
+ cfg = (config_t *)xmalloc_and_zero(sizeof(*cfg));
+
+ return cfg;
+}
- if(p->data.val)
+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
+}
+
+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(!found)
+ return NULL;
+
+ if(strcasecmp(found->variable, variable))
+ return NULL;
+
+ return found;
+}
+
+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;
- return p;
+ if(node->next)
+ {
+ found = (config_t *)node->next->data;
+ if(!strcasecmp(found->variable, cfg->variable))
+ return found;
+ }
}
- free(p);
return NULL;
}
-/*
- Get variable from a section in a configfile. returns -1 on failure.
-*/
-int
-readconfig(const char *fname, FILE *fp)
+int get_config_bool(config_t *cfg, int *result)
{
- char *line, *temp_buf;
- char *p, *q;
- int i, lineno = 0;
- config_t *cfg;
+cp
+ if(!cfg)
+ return 0;
- line = (char *)xmalloc(80 * sizeof(char));
- temp_buf = (char *)xmalloc(80 * sizeof(char));
-
- for(;;)
+ if(!strcasecmp(cfg->value, "yes"))
{
- if(fgets(line, 80, fp) == NULL)
- return 0;
+ *result = 1;
+ return 1;
+ }
+ else if(!strcasecmp(cfg->value, "no"))
+ {
+ *result = 0;
+ return 1;
+ }
- 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++;
+ syslog(LOG_ERR, _("\"yes\" or \"no\" expected for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
- if((p = strtok(line, "\t\n\r =")) == NULL)
- continue; /* no tokens on this line */
+ return 0;
+}
- if(p[0] == '#')
- continue; /* comment: ignore */
+int get_config_int(config_t *cfg, int *result)
+{
+cp
+ if(!cfg)
+ return 0;
- for(i = 0; hazahaza[i].name != NULL; i++)
- if(!strcasecmp(hazahaza[i].name, p))
- break;
+ if(sscanf(cfg->value, "%d", result) == 1)
+ return 1;
+
+ syslog(LOG_ERR, _("Integer expected for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
+ return 0;
+}
+
+int get_config_string(config_t *cfg, char **result)
+{
+cp
+ if(!cfg)
+ return 0;
+
+ *result = xstrdup(cfg->value);
+ return 1;
+}
+
+int get_config_address(config_t *cfg, struct addrinfo **result)
+{
+ struct addrinfo *ai;
+cp
+ if(!cfg)
+ return 0;
+
+ ai = str2addrinfo(cfg->value, NULL, 0);
+
+ if(ai)
+ {
+ *result = ai;
+ return 1;
+ }
+
+ syslog(LOG_ERR, _("Hostname or IP address expected for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
+ return 0;
+}
+
+int get_config_port(config_t *cfg, port_t *result)
+{
+cp
+ if(!cfg)
+ return 0;
+
+ if(sscanf(cfg->value, "%hu", result) == 1)
+ {
+ *result = htons(*result);
+ return 1;
+ }
+
+ syslog(LOG_ERR, _("Port number expected for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
+ return 0;
+}
+
+int get_config_subnet(config_t *cfg, subnet_t **result)
+{
+ subnet_t *subnet;
+cp
+ if(!cfg)
+ return 0;
+
+ subnet = str2net(cfg->value);
+
+ if(!subnet)
+ {
+ syslog(LOG_ERR, _("Subnet expected for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
+ return 0;
+ }
+
+ /* Teach newbies what subnets are... */
- if(!hazahaza[i].name)
+ if(((subnet->type == SUBNET_IPV4) && maskcheck((char *)&subnet->net.ipv4.address, subnet->net.ipv4.masklength, sizeof(ipv4_t)))
+ || ((subnet->type == SUBNET_IPV6) && maskcheck((char *)&subnet->net.ipv6.address, subnet->net.ipv6.masklength, sizeof(ipv6_t))))
+ {
+ syslog(LOG_ERR, _("Network address and mask length do not match for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
+ free(subnet);
+ return 0;
+ }
+
+ *result = subnet;
+
+ return 1;
+}
+
+/*
+ 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 */
{
- fprintf(stderr, "%s: %d: Invalid variable name `%s'.\n",
- fname, lineno, p);
- return -1;
+ if(feof(fp))
+ break;
+
+ /* otherwise: error; let the calling function print an error
+ message if applicable */
+ free(line);
+ return NULL;
}
- if(((q = strtok(NULL, "\t\n\r =")) == NULL) || q[0] == '#')
+ newline = strchr(p, '\n');
+ if(newline == NULL)
+ /* We haven't yet read everything to the end of the line */
{
- fprintf(stderr, "%s: %d: No value given for `%s'.\n",
- fname, lineno, hazahaza[i].name);
- return -1;
+ newsize = size << 1;
+ line = xrealloc(line, newsize);
+ idx = &line[size - 1];
+ maxlen = newsize - size + 1;
+ size = newsize;
}
-
- cfg = add_config_val(&config, hazahaza[i].argtype, q);
- if(cfg == NULL)
+ else
{
- fprintf(stderr, "%s: %d: Invalid value `%s' for variable `%s'.\n",
- fname, lineno, q, hazahaza[i].name);
- return -1;
+ *newline = '\0'; /* kill newline */
+ break; /* yay */
}
+ }
- cfg->which = hazahaza[i].which;
- if(!config)
- config = cfg;
+ if((buf != NULL) && (buflen != NULL))
+ {
+ *buflen = size;
+ *buf = line;
}
+ return line;
}
/*
- wrapper function for readconfig
+ Parse a configuration file and put the results in the configuration tree
+ starting at *base.
*/
-int
-read_config_file(const char *fname)
+int read_config_file(avl_tree_t *config_tree, const char *fname)
{
+ int err = -2; /* Parse error */
FILE *fp;
+ char *buffer, *line;
+ char *variable, *value;
+ int lineno = 0, ignore = 0;
+ config_t *cfg;
+ size_t bufsize;
+cp
if((fp = fopen (fname, "r")) == NULL)
{
- fprintf(stderr, "Could not open %s: %s\n", fname, sys_errlist[errno]);
- return 1;
+ syslog(LOG_ERR, _("Cannot open config file %s: %s"), fname, strerror(errno));
+ return -3;
}
- if(readconfig(fname, fp))
- return -1;
+ bufsize = 100;
+ buffer = xmalloc(bufsize);
+
+ for(;;)
+ {
+ if((line = readline(fp, &buffer, &bufsize)) == NULL)
+ {
+ err = -1;
+ break;
+ }
+
+ if(feof(fp))
+ {
+ err = 0;
+ break;
+ }
+
+ lineno++;
+
+ if((variable = strtok(line, "\t =")) == NULL)
+ continue; /* no tokens on this 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(buffer);
fclose (fp);
+cp
+ return err;
+}
- return 0;
+int read_server_config()
+{
+ char *fname;
+ int x;
+cp
+ asprintf(&fname, "%s/tinc.conf", confbase);
+ x = read_config_file(config_tree, fname);
+ if(x == -1) /* System error: complain */
+ {
+ syslog(LOG_ERR, _("Failed to read `%s': %s"), fname, strerror(errno));
+ }
+ free(fname);
+cp
+ return x;
}
-/*
- Look up the value of the config option type
-*/
-const config_t *
-get_config_val(which_t type)
+int isadir(const char* f)
{
- config_t *p;
+ struct stat s;
- for(p = config; p != NULL; p = p->next)
- if(p->which == type)
- return p;
+ if(stat(f, &s) < 0)
+ return 0;
+ else
+ return S_ISDIR(s.st_mode);
+}
- /* Not found */
- return NULL;
+int is_safe_path(const char *file)
+{
+ 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': %s"), f, strerror(errno));
+ return 0;
+ }
+
+ 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': %s"), f, strerror(errno));
+ return 0;
+ }
+
+ f = l;
+ goto check1;
+ }
+
+ *p = x;
+ f = file;
+
+check2:
+ if(lstat(f, &s) < 0 && errno != ENOENT)
+ {
+ syslog(LOG_ERR, _("Couldn't stat `%s': %s"), f, strerror(errno));
+ 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': %s"), f, strerror(errno));
+ return 0;
+ }
+
+ f = l;
+ goto check2;
+ }
+
+ 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, const char* mode)
+{
+ FILE *r;
+ char *directory;
+ char *fn;
+
+ /* 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);
+
+ if((fn = readline(stdin, NULL, NULL)) == NULL)
+ {
+ fprintf(stderr, _("Error while reading stdin: %s\n"), strerror(errno));
+ 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();
+ asprintf(&p, "%s/%s", directory, fn);
+ free(fn);
+ free(directory);
+ fn = p;
+ }
+
+ 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;
+ }
+
+ free(fn);
+
+ return r;
}