X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fconf.c;h=01c3fcd90873081b16030f2dcd4d979087bdda7c;hp=9bc25a79cecdfc517fbab696f3af33ca2ecedb2e;hb=44e9d6a2872fac55f7eb701ba576ed9f39a22e08;hpb=b1ecbf977722ec473fc8007acd39eb0de581de1a diff --git a/src/conf.c b/src/conf.c index 9bc25a79..01c3fcd9 100644 --- a/src/conf.c +++ b/src/conf.c @@ -1,9 +1,9 @@ /* conf.c -- configuration code - Copyright (C) 1998 Emphyrio, - Copyright (C) 1998,1999,2000 Ivo Timmermans - 2000 Guus Sliepen - 2000 Cris van Pelt + Copyright (C) 1998 Robert van der Meulen + 1998-2001 Ivo Timmermans + 2000,2001 Guus Sliepen + 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 @@ -19,10 +19,9 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: conf.c,v 1.9.4.6 2000/07/02 13:36:18 guus Exp $ + $Id: conf.c,v 1.9.4.42 2001/07/24 20:03:40 guus Exp $ */ - #include "config.h" #include @@ -31,46 +30,61 @@ #include #include #include +#include +#include +#include +#include +#include +#include #include +#include /* for cp */ #include "conf.h" #include "netutl.h" /* for strtoip */ -#include /* for cp */ #include "system.h" -config_t *config; +config_t *config = NULL; int debug_lvl = 0; int timeout = 0; /* seconds before timeout */ -char *configfilename = NULL; +char *confbase = NULL; /* directory in which all config files are */ +char *netname = NULL; /* name of the vpn network */ /* Will be set if HUP signal is received. It will be processed when it is safe. */ int sighup = 0; -typedef struct internal_config_t { - char *name; - enum which_t which; - int argtype; -} internal_config_t; - /* These are all the possible configurable values */ static internal_config_t hazahaza[] = { - { "AllowConnect", allowconnect, TYPE_BOOL }, /* Is not used anywhere. Remove? */ - { "ConnectTo", upstreamip, TYPE_NAME }, - { "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 }, - { "VpnMask", vpnmask, TYPE_IP }, - { "Hostnames", resolve_dns, TYPE_BOOL }, - { "IndirectData", indirectdata, TYPE_BOOL }, +/* Main configuration file keywords */ + { "ConnectTo", config_connectto, TYPE_NAME }, + { "Hostnames", config_hostnames, TYPE_BOOL }, + { "Interface", config_interface, TYPE_NAME }, + { "InterfaceIP", config_interfaceip, TYPE_IP }, + { "KeyExpire", config_keyexpire, TYPE_INT }, + { "MyVirtualIP", config_dummy, TYPE_IP }, + { "MyOwnVPNIP", config_dummy, TYPE_IP }, + { "Name", config_name, TYPE_NAME }, + { "PingTimeout", config_pingtimeout, TYPE_INT }, + { "PrivateKey", config_privatekey, TYPE_NAME }, + { "PrivateKeyFile", config_privatekeyfile, TYPE_NAME }, + { "TapDevice", config_tapdevice, TYPE_NAME }, + { "VpnMask", config_dummy, TYPE_IP }, +/* Host configuration file keywords */ + { "Address", config_address, TYPE_NAME }, + { "IndirectData", config_indirectdata, TYPE_BOOL }, + { "Port", config_port, TYPE_INT }, + { "PublicKey", config_publickey, TYPE_NAME }, + { "PublicKeyFile", config_publickeyfile, TYPE_NAME }, + { "RestrictAddress", config_restrictaddress, TYPE_BOOL }, + { "RestrictHosts", config_restricthosts, TYPE_BOOL }, + { "RestrictPort", config_restrictport, TYPE_BOOL }, + { "RestrictSubnets", config_restrictsubnets, TYPE_BOOL }, + { "Subnet", config_subnet, TYPE_IP }, /* Use IPv4 subnets only for now */ + { "TCPonly", config_tcponly, TYPE_BOOL }, + { "Mode", config_mode, TYPE_NAME }, { NULL, 0, 0 } }; @@ -80,12 +94,12 @@ static internal_config_t hazahaza[] = { config_t * add_config_val(config_t **cfg, int argtype, char *val) { - config_t *p, *r; + config_t *p; char *q; cp p = (config_t*)xmalloc(sizeof(*p)); p->data.val = 0; - + switch(argtype) { case TYPE_INT: @@ -113,156 +127,230 @@ cp if(p->data.val) { - if(*cfg) - { - r = *cfg; - while(r->next) - r = r->next; - r->next = p; - } - else - *cfg = p; - p->next = NULL; + p->next = *cfg; + *cfg = p; +cp return p; } - - free(p); + else + { + free(p); cp - return NULL; + return NULL; + } } /* - Get variable from a section in a configfile. returns -1 on failure. + 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. */ -int -readconfig(const char *fname, FILE *fp) +char *readline(FILE *fp, char **buf, size_t *buflen) { - char *line, *temp_buf; - char *p, *q; - int i, lineno = 0; - config_t *cfg; -cp - line = (char *)xmalloc(80 * sizeof(char)); - temp_buf = (char *)xmalloc(80 * sizeof(char)); - - for(;;) + 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 { - if(fgets(line, 80, fp) == NULL) - return 0; + size = 100; + line = xmalloc(size); + } - while(!index(line, '\n')) - { - fgets(temp_buf, (strlen(line)+1) * 80, fp); - if(!temp_buf) + maxlen = size; + idx = line; + *idx = 0; + for(;;) + { + errno = 0; + p = fgets(idx, maxlen, fp); + if(p == NULL) /* EOF or error */ + { + if(feof(fp)) break; - strcat(line, temp_buf); - line = (char *)xrealloc(line, (strlen(line)+1) * sizeof(char)); - } - lineno++; - - if((p = strtok(line, "\t\n\r =")) == NULL) - continue; /* no tokens on this line */ - - if(p[0] == '#') - continue; /* comment: ignore */ - - for(i = 0; hazahaza[i].name != NULL; i++) - if(!strcasecmp(hazahaza[i].name, p)) - break; - if(!hazahaza[i].name) - { - fprintf(stderr, _("%s: %d: Invalid variable name `%s'.\n"), - fname, lineno, p); - return -1; + /* 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; } -cp - return 0; + 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(config_t **base, const char *fname) { - int err; + int err = -2; /* Parse error */ FILE *fp; + char *buffer, *line; + char *p, *q; + int i, 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: %m"), fname); + return -3; } - err = readconfig(fname, fp); + bufsize = 100; + buffer = xmalloc(bufsize); + + for(;;) + { + + if((line = readline(fp, &buffer, &bufsize)) == NULL) + { + err = -1; + break; + } + + if(feof(fp)) + { + err = 0; + break; + } + + lineno++; + + if((p = strtok(line, "\t =")) == NULL) + continue; /* no tokens on this line */ + + if(p[0] == '#') + continue; /* comment: ignore */ + + if(!strcmp(p, "-----BEGIN")) + ignore = 1; + + if(ignore == 0) + { + for(i = 0; hazahaza[i].name != NULL; i++) + if(!strcasecmp(hazahaza[i].name, p)) + break; + + if(!hazahaza[i].name) + { + syslog(LOG_ERR, _("Invalid variable name `%s' on line %d while reading config file %s"), + p, lineno, fname); + break; + } + + if(((q = strtok(NULL, "\t\n\r =")) == NULL) || q[0] == '#') + { + syslog(LOG_ERR, _("No value for variable `%s' on line %d while reading config file %s"), + hazahaza[i].name, lineno, fname); + break; + } + + cfg = add_config_val(base, hazahaza[i].argtype, q); + if(cfg == NULL) + { + syslog(LOG_ERR, _("Invalid value for variable `%s' on line %d while reading config file %s"), + hazahaza[i].name, lineno, fname); + break; + } + + cfg->which = hazahaza[i].which; + if(!config) + config = cfg; + } + + if(!strcmp(p, "-----END")) + ignore = 0; + } + + free(buffer); fclose (fp); cp return err; } -/* - Look up the value of the config option type -*/ -const config_t * -get_config_val(which_t type) +int read_server_config() { - config_t *p; + char *fname; + int x; cp - for(p = config; p != NULL; p = p->next) - if(p->which == type) - return p; + asprintf(&fname, "%s/tinc.conf", confbase); + x = read_config_file(&config, fname); + if(x == -1) /* System error: complain */ + { + syslog(LOG_ERR, _("Failed to read `%s': %m"), + fname); + } + free(fname); cp - /* Not found */ - return NULL; + return x; } /* - Support for multiple config lines. - Index is used to get a specific value, 0 being the first, 1 the second etc. + Look up the value of the config option type */ -const config_t * -get_next_config_val(which_t type, int index) +const config_t *get_config_val(config_t *p, which_t type) { - config_t *p; -cp - for(p = config; p != NULL; p = p->next) +cp + for(; p != NULL; p = p->next) if(p->which == type) - if(--index < 0) - return p; -cp - /* Not found */ - return NULL; + break; +cp + return p; } /* Remove the complete configuration tree. */ -void clear_config() +void clear_config(config_t **base) { config_t *p, *next; cp - for(p = config; p != NULL; p = next) + for(p = *base; p != NULL; p = next) { next = p->next; if(p->data.ptr && (p->argtype == TYPE_NAME)) @@ -271,6 +359,188 @@ cp } free(p); } - config = NULL; + *base = NULL; cp } + +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': %m"), + f); + 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': %m"), f); + 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': %m"), + f); + 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': %m"), f); + 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; +}