Fix all warnings when compiling with -Wall -W -pedantic.
[oweals/tinc.git] / src / conf.c
index e2b64429d8fd3ee1616c59efb0ebbbaa7c3b9e22..03887991cdc5bc80908ff124523b3dd3234ba895 100644 (file)
@@ -2,9 +2,9 @@
     conf.c -- configuration code
     Copyright (C) 1998 Robert van der Meulen
                   1998-2005 Ivo Timmermans
-                  2000-2012 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2014 Guus Sliepen <guus@tinc-vpn.org>
                   2010-2011 Julien Muchembled <jm@jmuchemb.eu>
-                 2000 Cris van Pelt
+                  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
 #include "conf.h"
 #include "list.h"
 #include "logger.h"
-#include "netutl.h"                            /* for str2address */
+#include "netutl.h"                             /* for str2address */
 #include "protocol.h"
-#include "utils.h"                             /* for cp */
+#include "utils.h"                              /* for cp */
 #include "xalloc.h"
 
 avl_tree_t *config_tree;
 
-int pinginterval = 0;                  /* seconds between pings */
-int pingtimeout = 0;                   /* seconds to wait for response */
-char *confbase = NULL;                 /* directory in which all config files are */
-char *netname = NULL;                  /* name of the vpn network */
-list_t *cmdline_conf = NULL;   /* global/host configuration values given at the command line */
+int pinginterval = 0;                   /* seconds between pings */
+int pingtimeout = 0;                    /* seconds to wait for response */
+char *confbase = NULL;                  /* directory in which all config files are */
+char *netname = NULL;                   /* name of the vpn network */
+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) {
@@ -47,27 +47,31 @@ static int config_compare(const config_t *a, const config_t *b) {
 
        result = strcasecmp(a->variable, b->variable);
 
-       if(result)
+       if(result) {
                return result;
+       }
 
        /* give priority to command line options */
        result = !b->file - !a->file;
-       if (result)
+
+       if(result) {
                return result;
+       }
 
        result = a->line - b->line;
 
-       if(result)
+       if(result) {
                return result;
-       else
+       } else {
                return a->file ? strcmp(a->file, b->file) : 0;
+       }
 }
 
-void init_configuration(avl_tree_t ** config_tree) {
+void init_configuration(avl_tree_t **config_tree) {
        *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) {
        avl_delete_tree(*config_tree);
        *config_tree = NULL;
 }
@@ -77,14 +81,17 @@ config_t *new_config(void) {
 }
 
 void free_config(config_t *cfg) {
-       if(cfg->variable)
+       if(cfg->variable) {
                free(cfg->variable);
+       }
 
-       if(cfg->value)
+       if(cfg->value) {
                free(cfg->value);
+       }
 
-       if(cfg->file)
+       if(cfg->file) {
                free(cfg->file);
+       }
 
        free(cfg);
 }
@@ -102,11 +109,13 @@ config_t *lookup_config(const avl_tree_t *config_tree, char *variable) {
 
        found = avl_search_closest_greater(config_tree, &cfg);
 
-       if(!found)
+       if(!found) {
                return NULL;
+       }
 
-       if(strcasecmp(found->variable, variable))
+       if(strcasecmp(found->variable, variable)) {
                return NULL;
+       }
 
        return found;
 }
@@ -121,8 +130,9 @@ config_t *lookup_config_next(const avl_tree_t *config_tree, const config_t *cfg)
                if(node->next) {
                        found = node->next->data;
 
-                       if(!strcasecmp(found->variable, cfg->variable))
+                       if(!strcasecmp(found->variable, cfg->variable)) {
                                return found;
+                       }
                }
        }
 
@@ -130,8 +140,9 @@ config_t *lookup_config_next(const avl_tree_t *config_tree, const config_t *cfg)
 }
 
 bool get_config_bool(const config_t *cfg, bool *result) {
-       if(!cfg)
+       if(!cfg) {
                return false;
+       }
 
        if(!strcasecmp(cfg->value, "yes")) {
                *result = true;
@@ -142,27 +153,30 @@ bool get_config_bool(const config_t *cfg, bool *result) {
        }
 
        logger(LOG_ERR, "\"yes\" or \"no\" expected for configuration variable %s in %s line %d",
-                  cfg->variable, cfg->file, cfg->line);
+              cfg->variable, cfg->file, cfg->line);
 
        return false;
 }
 
 bool get_config_int(const config_t *cfg, int *result) {
-       if(!cfg)
+       if(!cfg) {
                return false;
+       }
 
-       if(sscanf(cfg->value, "%d", result) == 1)
+       if(sscanf(cfg->value, "%d", result) == 1) {
                return true;
+       }
 
        logger(LOG_ERR, "Integer expected for configuration variable %s in %s line %d",
-                  cfg->variable, cfg->file, cfg->line);
+              cfg->variable, cfg->file, cfg->line);
 
        return false;
 }
 
 bool get_config_string(const config_t *cfg, char **result) {
-       if(!cfg)
+       if(!cfg) {
                return false;
+       }
 
        *result = xstrdup(cfg->value);
 
@@ -172,8 +186,9 @@ bool get_config_string(const config_t *cfg, char **result) {
 bool get_config_address(const config_t *cfg, struct addrinfo **result) {
        struct addrinfo *ai;
 
-       if(!cfg)
+       if(!cfg) {
                return false;
+       }
 
        ai = str2addrinfo(cfg->value, NULL, 0);
 
@@ -183,31 +198,32 @@ bool get_config_address(const config_t *cfg, struct addrinfo **result) {
        }
 
        logger(LOG_ERR, "Hostname or IP address expected for configuration variable %s in %s line %d",
-                  cfg->variable, cfg->file, cfg->line);
+              cfg->variable, cfg->file, cfg->line);
 
        return false;
 }
 
-bool get_config_subnet(const config_t *cfg, subnet_t ** result) {
-       subnet_t subnet = {NULL};
+bool get_config_subnet(const config_t *cfg, subnet_t **result) {
+       subnet_t subnet = {0};
 
-       if(!cfg)
+       if(!cfg) {
                return false;
+       }
 
        if(!str2net(&subnet, cfg->value)) {
                logger(LOG_ERR, "Subnet expected for configuration variable %s in %s line %d",
-                          cfg->variable, cfg->file, cfg->line);
+                      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(ipv4_t)))
-               || ((subnet.type == SUBNET_IPV6)
-               && !maskcheck(&subnet.net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof(ipv6_t)))) {
+                       && !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)))) {
                logger(LOG_ERR, "Network address and prefix length do not match for configuration variable %s in %s line %d",
-                          cfg->variable, cfg->file, cfg->line);
+                      cfg->variable, cfg->file, cfg->line);
                return false;
        }
 
@@ -219,26 +235,31 @@ bool get_config_subnet(const config_t *cfg, subnet_t ** result) {
 /*
   Read exactly one line and strip the trailing newline if any.
 */
-static char *readline(FILE * fp, char *buf, size_t buflen) {
+static char *readline(FILE *fp, char *buf, size_t buflen) {
        char *newline = NULL;
        char *p;
 
-       if(feof(fp))
+       if(feof(fp)) {
                return NULL;
+       }
 
        p = fgets(buf, buflen, fp);
 
-       if(!p)
+       if(!p) {
                return NULL;
+       }
 
        newline = strchr(p, '\n');
 
-       if(!newline)
+       if(!newline) {
                return buf;
+       }
 
-       *newline = '\0';        /* kill newline */
-       if(newline > p && newline[-1] == '\r')  /* and carriage return if necessary */
+       *newline = '\0';        /* kill newline */
+
+       if(newline > p && newline[-1] == '\r') { /* and carriage return if necessary */
                newline[-1] = '\0';
+       }
 
        return buf;
 }
@@ -250,26 +271,32 @@ config_t *parse_config_line(char *line, const char *fname, int lineno) {
        variable = value = line;
 
        eol = line + strlen(line);
-       while(strchr("\t ", *--eol))
+
+       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)
+
+               if(fname)
                        logger(LOG_ERR, "%s `%s' on line %d while reading config file %s",
-                               err, variable, lineno, fname);
+                              err, variable, lineno, fname);
                else
                        logger(LOG_ERR, "%s `%s' in command line option %d",
-                               err, variable, lineno);
+                              err, variable, lineno);
+
                return NULL;
        }
 
@@ -303,33 +330,41 @@ bool read_config_file(avl_tree_t *config_tree, const char *fname) {
        }
 
        for(;;) {
-               line = readline(fp, buffer, sizeof buffer);
+               line = readline(fp, buffer, sizeof(buffer));
 
                if(!line) {
-                       if(feof(fp))
+                       if(feof(fp)) {
                                result = true;
+                       }
+
                        break;
                }
 
                lineno++;
 
-               if(!*line || *line == '#')
+               if(!*line || *line == '#') {
                        continue;
+               }
 
                if(ignore) {
-                       if(!strncmp(line, "-----END", 8))
+                       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)
+
+               if(!cfg) {
                        break;
+               }
+
                config_add(config_tree, cfg);
        }
 
@@ -339,87 +374,92 @@ bool read_config_file(avl_tree_t *config_tree, const char *fname) {
 }
 
 void read_config_options(avl_tree_t *config_tree, const char *prefix) {
-       list_node_t *node, *next;
        size_t prefix_len = prefix ? strlen(prefix) : 0;
 
-       for(node = cmdline_conf->tail; node; node = next) {
-               config_t *orig_cfg, *cfg = (config_t *)node->data;
-               next = node->prev;
+       for(const list_node_t *node = cmdline_conf->tail; node; node = node->prev) {
+               const config_t *cfg = node->data;
 
                if(!prefix) {
-                       if(strchr(cfg->variable, '.'))
+                       if(strchr(cfg->variable, '.')) {
                                continue;
-                       node->data = NULL;
-                       list_unlink_node(cmdline_conf, node);
+                       }
                } else {
                        if(strncmp(prefix, cfg->variable, prefix_len) ||
-                          cfg->variable[prefix_len] != '.')
+                                       cfg->variable[prefix_len] != '.') {
                                continue;
-                       /* Because host configuration is parsed again when
-                          reconnecting, nodes must not be freed when a prefix
-                          is given. */
-                       orig_cfg = cfg;
-                       cfg = new_config();
-                       cfg->variable = xstrdup(orig_cfg->variable + prefix_len + 1);
-                       cfg->value = xstrdup(orig_cfg->value);
-                       cfg->file = NULL;
-                       cfg->line = orig_cfg->line;
+                       }
                }
-               config_add(config_tree, cfg);
+
+               config_t *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;
+       char fname[PATH_MAX];
        bool x;
 
        read_config_options(config_tree, NULL);
 
-       xasprintf(&fname, "%s/tinc.conf", confbase);
+       snprintf(fname, sizeof(fname), "%s/tinc.conf", confbase);
+       errno = 0;
        x = read_config_file(config_tree, fname);
 
        // We will try to read the conf files in the "conf.d" dir
-       if (x) {
-               char * dname;
-               xasprintf(&dname, "%s/conf.d", confbase);
-               DIR *dir = opendir (dname);
+       if(x) {
+               char dname[PATH_MAX];
+               snprintf(dname, sizeof(dname), "%s/conf.d", confbase);
+               DIR *dir = opendir(dname);
+
                // If we can find this dir
-               if (dir) { 
+               if(dir) {
                        struct dirent *ep;
+
                        // We list all the files in it
-                       while (x && (ep = readdir (dir))) {
+                       while(x && (ep = readdir(dir))) {
                                size_t l = strlen(ep->d_name);
+
                                // And we try to read the ones that end with ".conf"
-                               if (l > 5 && !strcmp(".conf", & ep->d_name[ l - 5 ])) {
-                                       free(fname);
-                                       xasprintf(&fname, "%s/%s", dname, ep->d_name);
-                                       logger(LOG_DEBUG, "Reading conf file \"%s\"", fname);
+                               if(l > 5 && !strcmp(".conf", & ep->d_name[ l - 5 ])) {
+                                       if((size_t)snprintf(fname, sizeof(fname), "%s/%s", dname, ep->d_name) >= sizeof(fname)) {
+                                               logger(LOG_ERR, "Pathname too long: %s/%s", dname, ep->d_name);
+                                               return false;
+                                       }
+
                                        x = read_config_file(config_tree, fname);
                                }
                        }
-                       closedir (dir);
+
+                       closedir(dir);
                }
-               free(dname);
        }
 
-       if(!x) {                                /* System error: complain */
+       if(!x && errno) {
                logger(LOG_ERR, "Failed to read `%s': %s", fname, strerror(errno));
        }
 
-       free(fname);
-
        return x;
 }
 
 bool read_connection_config(connection_t *c) {
-       char *fname;
+       char fname[PATH_MAX];
        bool x;
 
        read_config_options(c->config_tree, c->name);
 
-       xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
+       snprintf(fname, sizeof(fname), "%s/hosts/%s", confbase, c->name);
        x = read_config_file(c->config_tree, fname);
-       free(fname);
 
        return x;
 }
@@ -431,34 +471,38 @@ static void disable_old_keys(const char *filename) {
        FILE *r, *w;
 
        r = fopen(filename, "r");
-       if(!r)
+
+       if(!r) {
                return;
+       }
 
-       snprintf(tmpfile, sizeof tmpfile, "%s.tmp", filename);
+       snprintf(tmpfile, sizeof(tmpfile), "%s.tmp", filename);
 
        w = fopen(tmpfile, "w");
 
-       while(fgets(buf, sizeof buf, r)) {
-               if(!strncmp(buf, "-----BEGIN RSA", 14)) {       
+       while(fgets(buf, sizeof(buf), r)) {
+               if(!strncmp(buf, "-----BEGIN RSA", 14)) {
                        buf[11] = 'O';
                        buf[12] = 'L';
                        buf[13] = 'D';
                        disabled = true;
-               }
-               else if(!strncmp(buf, "-----END RSA", 12)) {    
+               } else if(!strncmp(buf, "-----END RSA", 12)) {
                        buf[ 9] = 'O';
                        buf[10] = 'L';
                        buf[11] = 'D';
                        disabled = true;
                }
+
                if(w && fputs(buf, w) < 0) {
                        disabled = false;
                        break;
                }
        }
 
-       if(w)
+       if(w) {
                fclose(w);
+       }
+
        fclose(r);
 
        if(!w && disabled) {
@@ -470,10 +514,12 @@ static void disable_old_keys(const char *filename) {
 #ifdef HAVE_MINGW
                // We cannot atomically replace files on Windows.
                char bakfile[PATH_MAX] = "";
-               snprintf(bakfile, sizeof bakfile, "%s.bak", filename);
+               snprintf(bakfile, sizeof(bakfile), "%s.bak", filename);
+
                if(rename(filename, bakfile) || rename(tmpfile, filename)) {
                        rename(bakfile, filename);
 #else
+
                if(rename(tmpfile, filename)) {
 #endif
                        fprintf(stderr, "Warning: old key(s) found, remove them by hand!\n");
@@ -490,8 +536,9 @@ static void disable_old_keys(const char *filename) {
 
 FILE *ask_and_open(const char *filename, const char *what) {
        FILE *r;
-       char *directory;
+       char directory[PATH_MAX];
        char line[PATH_MAX];
+       char abspath[PATH_MAX];
        const char *fn;
 
        /* Check stdin and stdout */
@@ -503,37 +550,43 @@ FILE *ask_and_open(const char *filename, const char *what) {
        } else {
                /* Ask for a file and/or directory name. */
                fprintf(stdout, "Please enter a file to save %s to [%s]: ",
-                               what, filename);
+                       what, filename);
                fflush(stdout);
 
-               fn = readline(stdin, line, sizeof line);
+               fn = readline(stdin, line, sizeof(line));
 
                if(!fn) {
                        fprintf(stderr, "Error while reading stdin: %s\n",
-                                       strerror(errno));
+                               strerror(errno));
                        return NULL;
                }
 
                if(!strlen(fn))
                        /* User just pressed enter. */
+               {
                        fn = filename;
+               }
        }
 
 #ifdef HAVE_MINGW
+
        if(fn[0] != '\\' && fn[0] != '/' && !strchr(fn, ':')) {
 #else
+
        if(fn[0] != '/') {
 #endif
                /* The directory is a relative path or a filename. */
-               char *p;
+               getcwd(directory, sizeof(directory));
+
+               if((size_t)snprintf(abspath, sizeof(abspath), "%s/%s", directory, fn) >= sizeof(abspath)) {
+                       fprintf(stderr, "Pathname too long: %s/%s\n", directory, fn);
+                       return NULL;
+               }
 
-               directory = get_current_dir_name();
-               xasprintf(&p, "%s/%s", directory, fn);
-               free(directory);
-               fn = p;
+               fn = abspath;
        }
 
-       umask(0077);                            /* Disallow everything for group and other */
+       umask(0077);                            /* Disallow everything for group and other */
 
        disable_old_keys(fn);
 
@@ -543,7 +596,7 @@ FILE *ask_and_open(const char *filename, const char *what) {
 
        if(!r) {
                fprintf(stderr, "Error opening file `%s': %s\n",
-                               fn, strerror(errno));
+                       fn, strerror(errno));
                return NULL;
        }