/*
conf.c -- configuration code
Copyright (C) 1998 Robert van der Meulen
- 1998-2002 Ivo Timmermans <itimmermans@bigfoot.com>
- 2000-2002 Guus Sliepen <guus@sliepen.warande.net>
+ 1998-2002 Ivo Timmermans <ivo@o2w.nl>
+ 2000-2002 Guus Sliepen <guus@sliepen.eu.org>
2000 Cris van Pelt <tribbel@arise.dhs.org>
This program is free software; you can redistribute it and/or modify
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: conf.c,v 1.9.4.53 2002/02/18 16:25:16 guus Exp $
+ $Id: conf.c,v 1.9.4.61 2002/09/15 12:26:24 guus Exp $
*/
#include "config.h"
#include <string.h>
#include <xalloc.h>
-#include <utils.h> /* for cp */
+#include <utils.h> /* for cp */
#include <avl_tree.h>
#include "conf.h"
-#include "netutl.h" /* for str2address */
+#include "netutl.h" /* for str2address */
#include "system.h"
avl_tree_t *config_tree;
int debug_lvl = 0;
-int pingtimeout = 0; /* seconds before timeout */
-char *confbase = NULL; /* directory in which all config files are */
-char *netname = NULL; /* name of the vpn network */
+int pingtimeout = 0; /* seconds before timeout */
+char *confbase = NULL; /* directory in which all config files are */
+char *netname = NULL; /* name of the vpn network */
int config_compare(config_t *a, config_t *b)
{
- int result;
+ int result;
- result = strcasecmp(a->variable, b->variable);
+ result = strcasecmp(a->variable, b->variable);
- if(result)
- return result;
+ if(result)
+ return result;
- result = a->line - b->line;
+ result = a->line - b->line;
- if(result)
- return result;
- else
- return strcmp(a->file, b->file);
+ if(result)
+ return result;
+ else
+ return strcmp(a->file, b->file);
}
-void init_configuration(avl_tree_t **config_tree)
+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
+ cp();
+
+ *config_tree = avl_alloc_tree((avl_compare_t) config_compare, (avl_action_t) free_config);
}
-void exit_configuration(avl_tree_t **config_tree)
+void exit_configuration(avl_tree_t ** config_tree)
{
-cp
- avl_delete_tree(*config_tree);
- *config_tree = NULL;
-cp
+ cp();
+
+ avl_delete_tree(*config_tree);
+ *config_tree = NULL;
}
config_t *new_config(void)
{
- config_t *cfg;
-cp
- cfg = (config_t *)xmalloc_and_zero(sizeof(*cfg));
+ cp();
- return cfg;
+ return (config_t *) xmalloc_and_zero(sizeof(config_t));
}
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
+ cp();
+
+ if(cfg->variable)
+ free(cfg->variable);
+
+ if(cfg->value)
+ free(cfg->value);
+
+ if(cfg->file)
+ free(cfg->file);
+
+ free(cfg);
}
void config_add(avl_tree_t *config_tree, config_t *cfg)
{
-cp
- avl_insert(config_tree, cfg);
-cp
+ cp();
+
+ avl_insert(config_tree, cfg);
}
config_t *lookup_config(avl_tree_t *config_tree, char *variable)
{
- config_t cfg, *found;
-cp
- cfg.variable = variable;
- cfg.file = "";
- cfg.line = 0;
+ config_t cfg, *found;
+
+ cp();
+
+ cfg.variable = variable;
+ cfg.file = "";
+ cfg.line = 0;
- found = avl_search_closest_greater(config_tree, &cfg);
+ found = avl_search_closest_greater(config_tree, &cfg);
- if(!found)
- return NULL;
+ if(!found)
+ return NULL;
- if(strcmp(found->variable, variable))
- return NULL;
+ if(strcasecmp(found->variable, variable))
+ return NULL;
- return found;
+ 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)
- {
- if(node->next)
- {
- found = (config_t *)node->next->data;
- if(!strcmp(found->variable, cfg->variable))
- return found;
- }
- }
-
- return NULL;
+ avl_node_t *node;
+ config_t *found;
+
+ cp();
+
+ node = avl_search_node(config_tree, cfg);
+
+ if(node) {
+ if(node->next) {
+ found = (config_t *) node->next->data;
+
+ if(!strcasecmp(found->variable, cfg->variable))
+ return found;
+ }
+ }
+
+ return NULL;
}
int get_config_bool(config_t *cfg, int *result)
{
-cp
- if(!cfg)
- return 0;
-
- if(!strcasecmp(cfg->value, "yes"))
- {
- *result = 1;
- return 1;
- }
- else if(!strcasecmp(cfg->value, "no"))
- {
- *result = 0;
- return 1;
- }
-
- syslog(LOG_ERR, _("\"yes\" or \"no\" expected for configuration variable %s in %s line %d"),
- cfg->variable, cfg->file, cfg->line);
-
- return 0;
+ cp();
+
+ if(!cfg)
+ return 0;
+
+ if(!strcasecmp(cfg->value, "yes")) {
+ *result = 1;
+ return 1;
+ } else if(!strcasecmp(cfg->value, "no")) {
+ *result = 0;
+ return 1;
+ }
+
+ syslog(LOG_ERR, _("\"yes\" or \"no\" expected for configuration variable %s in %s line %d"),
+ cfg->variable, cfg->file, cfg->line);
+
+ return 0;
}
int get_config_int(config_t *cfg, int *result)
{
-cp
- if(!cfg)
- return 0;
+ cp();
+
+ if(!cfg)
+ return 0;
- if(sscanf(cfg->value, "%d", result) == 1)
- return 1;
+ 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;
+ 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;
+ cp();
+
+ if(!cfg)
+ return 0;
- *result = xstrdup(cfg->value);
- return 1;
+ *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;
-}
+ struct addrinfo *ai;
-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;
+ 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_subnet(config_t *cfg, subnet_t **result)
+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(((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;
+ 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(((subnet->type == SUBNET_IPV4)
+ && maskcheck(&subnet->net.ipv4.address, subnet->net.ipv4.prefixlength, sizeof(ipv4_t)))
+ || ((subnet->type == SUBNET_IPV6)
+ && maskcheck(&subnet->net.ipv6.address, subnet->net.ipv6.prefixlength, sizeof(ipv6_t)))) {
+ syslog(LOG_ERR, _ ("Network address and prefix 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;
}
/*
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 *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;
+ 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 && buflen) {
+ size = *buflen;
+ line = *buf;
+ } else {
+ size = 100;
+ line = xmalloc(size);
}
- 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;
+ maxlen = size;
+ idx = line;
+ *idx = 0;
+
+ for(;;) {
+ errno = 0;
+ p = fgets(idx, maxlen, fp);
+
+ if(!p) { /* 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) { /* 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 */
+ }
}
- else
- {
- *newline = '\0'; /* kill newline */
- break; /* yay */
+
+ if(buf && buflen) {
+ *buflen = size;
+ *buf = line;
}
- }
-
- if((buf != NULL) && (buflen != NULL))
- {
- *buflen = size;
- *buf = line;
- }
- return line;
+
+ return line;
}
/*
*/
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;
+ 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();
+
+ fp = fopen(fname, "r");
+
+ if(!fp) {
+ syslog(LOG_ERR, _("Cannot open config file %s: %s"), fname,
+ strerror(errno));
+ return -3;
}
- if(feof(fp))
- {
- err = 0;
- break;
- }
+ bufsize = 100;
+ buffer = xmalloc(bufsize);
- lineno++;
+ for(;;) {
+ line = readline(fp, &buffer, &bufsize);
- if((variable = strtok(line, "\t =")) == NULL)
- continue; /* no tokens on this line */
+ if(!line) {
+ err = -1;
+ break;
+ }
- if(variable[0] == '#')
- continue; /* comment: ignore */
+ if(feof(fp)) {
+ err = 0;
+ break;
+ }
- if(!strcmp(variable, "-----BEGIN"))
- ignore = 1;
+ lineno++;
- 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;
- }
+ variable = strtok(line, "\t =");
- cfg = new_config();
- cfg->variable = xstrdup(variable);
- cfg->value = xstrdup(value);
- cfg->file = xstrdup(fname);
- cfg->line = lineno;
+ if(!variable)
+ continue; /* no tokens on this line */
- config_add(config_tree, cfg);
- }
+ if(variable[0] == '#')
+ continue; /* comment: ignore */
- if(!strcmp(variable, "-----END"))
- ignore = 0;
- }
+ if(!strcmp(variable, "-----BEGIN"))
+ ignore = 1;
- free(buffer);
- fclose (fp);
-cp
- return err;
+ if(!ignore) {
+ value = strtok(NULL, "\t\n\r =");
+
+ if(!value || 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);
+
+ 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;
+ 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);
+
+ return x;
}
-int isadir(const char* f)
+int isadir(const char *f)
{
- struct stat s;
+ struct stat s;
- if(stat(f, &s) < 0)
- return 0;
- else
- return S_ISDIR(s.st_mode);
+ 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];
+ 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;
+ }
- if(*file != '/')
- {
- syslog(LOG_ERR, _("`%s' is not an absolute path"), file);
- return 0;
- }
+ p = strrchr(file, '/');
- p = strrchr(file, '/');
+ if(p == file) /* It's in the root */
+ p++;
- if(p == file) /* It's in the root */
- p++;
+ x = *p;
+ *p = '\0';
- x = *p;
- *p = '\0';
+ f = file;
- 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;
+ 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;
+ 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 *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;
+ 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);
+
+ fn = readline(stdin, NULL, NULL);
+
+ if(!fn) {
+ fprintf(stderr, _("Error while reading stdin: %s\n"),
+ strerror(errno));
+ return NULL;
+ }
+
+ if(!strlen(fn))
+ /* User just pressed enter. */
+ fn = xstrdup(filename);
}
- 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;
+ if(!strchr(fn, '/') || 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 */
+
+ r = fopen(fn, mode);
+
+ if(!r) {
+ 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;
}