--- /dev/null
+/*
+ read_conf.c -- read the configuration files
+ Copyright (C) 1998 Robert van der Meulen
+ 1998-2002 Ivo Timmermans <ivo@o2w.nl>
+ 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
+ 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ $Id: read_conf.c,v 1.1 2002/04/28 12:46:26 zarq Exp $
+*/
+
+#include "config.h"
+
+#include <ctype.h>
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <xalloc.h>
+#include <utils.h> /* for cp */
+#include <avl_tree.h>
+
+#include "conf.h"
+#include "netutl.h" /* for str2address */
+#include "logging.h"
+
+#include "system.h"
+
+/*
+ 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 */
+ }
+ }
+
+ 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(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)
+ {
+ syslog(LOG_ERR, _("Cannot open config file %s: %s"), fname, strerror(errno));
+ return -3;
+ }
+
+ 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;
+}
+
+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;
+}
+
+int isadir(const char* f)
+{
+ struct stat s;
+
+ if(stat(f, &s) < 0)
+ return 0;
+ else
+ return S_ISDIR(s.st_mode);
+}
+
+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;
+}
+
+int read_connection_config(connection_t *c)
+{
+ char *fname;
+ int x;
+cp
+ asprintf(&fname, "%s/hosts/%s", confbase, c->name);
+ x = read_config_file(c->config_tree, fname);
+ free(fname);
+cp
+ return x;
+}
projects / tinc / blobdiff