X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fconf.c;h=1a3c82ae2e8c45e5cf07cceaf2945bcc9eaac6bf;hb=53522b1c11222273c7b41f72b374e759d13b2165;hp=827da68181bfc2bbc8eb5d8083878b6a4dcbaf36;hpb=075e6828a7533e7daa790225f17aa6bb39703278;p=meshlink diff --git a/src/conf.c b/src/conf.c index 827da681..1a3c82ae 100644 --- a/src/conf.c +++ b/src/conf.c @@ -1,9 +1,6 @@ /* - conf.c -- configuration code - Copyright (C) 1998 Robert van der Meulen - 1998-2005 Ivo Timmermans - 2000-2009 Guus Sliepen - 2000 Cris van Pelt + econf.c -- configuration code + Copyright (C) 2018 Guus Sliepen 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 @@ -15,400 +12,559 @@ 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. - - $Id$ + 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., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "system.h" +#include -#include "splay_tree.h" #include "conf.h" +#include "crypto.h" #include "logger.h" -#include "netutl.h" /* for str2address */ -#include "utils.h" /* for cp */ +#include "meshlink_internal.h" #include "xalloc.h" +#include "packmsg.h" -splay_tree_t *config_tree; +/// Generate a path to the main configuration file. +static void make_main_path(meshlink_handle_t *mesh, char *path, size_t len) { + snprintf(path, len, "%s" SLASH "meshlink.conf", mesh->confbase); +} -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 */ +/// Generate a path to a host configuration file. +static void make_host_path(meshlink_handle_t *mesh, const char *name, char *path, size_t len) { + snprintf(path, len, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name); +} -static int config_compare(const config_t *a, const config_t *b) { - int result; +/// Generate a path to an unused invitation file. +static void make_invitation_path(meshlink_handle_t *mesh, const char *name, char *path, size_t len) { + snprintf(path, len, "%s" SLASH "invitations" SLASH "%s", mesh->confbase, name); +} - result = strcasecmp(a->variable, b->variable); +/// Generate a path to a used invitation file. +static void make_used_invitation_path(meshlink_handle_t *mesh, const char *name, char *path, size_t len) { + snprintf(path, len, "%s" SLASH "invitations" SLASH "%s.used", mesh->confbase, name); +} - if(result) - return result; +/// Remove a directory recursively +static void deltree(const char *dirname) { + DIR *d = opendir(dirname); - result = a->line - b->line; + if(d) { + struct dirent *ent; - if(result) - return result; - else - return strcmp(a->file, b->file); -} + while((ent = readdir(d))) { + if(ent->d_name[0] == '.') { + continue; + } -void init_configuration(splay_tree_t ** config_tree) { - cp(); + char filename[PATH_MAX]; + snprintf(filename, sizeof(filename), "%s" SLASH "%s", dirname, ent->d_name); - *config_tree = splay_alloc_tree((splay_compare_t) config_compare, (splay_action_t) free_config); -} + if(unlink(filename)) { + deltree(filename); + } + } -void exit_configuration(splay_tree_t ** config_tree) { - cp(); + closedir(d); + } - splay_delete_tree(*config_tree); - *config_tree = NULL; + rmdir(dirname); } -config_t *new_config(void) { - cp(); +/// Create a fresh configuration directory +bool config_init(meshlink_handle_t *mesh) { + if(!mesh->confbase) { + return true; + } - return xmalloc_and_zero(sizeof(config_t)); -} + if(mkdir(mesh->confbase, 0700) && errno != EEXIST) { + logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", mesh->confbase, strerror(errno)); + return false; + } -void free_config(config_t *cfg) { - cp(); + char path[PATH_MAX]; - if(cfg->variable) - free(cfg->variable); + // Remove meshlink.conf + snprintf(path, sizeof(path), "%s" SLASH "meshlink.conf", mesh->confbase); + unlink(path); - if(cfg->value) - free(cfg->value); + // Remove any host config files + snprintf(path, sizeof(path), "%s" SLASH "hosts", mesh->confbase); + deltree(path); - if(cfg->file) - free(cfg->file); + if(mkdir(path, 0700) && errno != EEXIST) { + logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno)); + return false; + } - free(cfg); -} + // Remove any invitation files + snprintf(path, sizeof(path), "%s" SLASH "invitations", mesh->confbase); + deltree(path); -void config_add(splay_tree_t *config_tree, config_t *cfg) { - cp(); + if(mkdir(path, 0700) && errno != EEXIST) { + logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno)); + return false; + } - splay_insert(config_tree, cfg); + return true; } -config_t *lookup_config(splay_tree_t *config_tree, char *variable) { - config_t cfg, *found; +/// Wipe an existing configuration directory +bool config_destroy(const char *confbase) { + char path[PATH_MAX]; - cp(); + // Remove meshlink.conf + snprintf(path, sizeof(path), "%s" SLASH "meshlink.conf", confbase); - cfg.variable = variable; - cfg.file = ""; - cfg.line = 0; + if(unlink(path)) { + if(errno == ENOENT) { + meshlink_errno = MESHLINK_ENOENT; + return false; + } else { + logger(NULL, MESHLINK_ERROR, "Cannot delete %s: %s\n", path, strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + return false; + } + } - found = splay_search_closest_greater(config_tree, &cfg); + deltree(confbase); + return true; +} - if(!found) - return NULL; +/// Check the presence of the main configuration file. +bool main_config_exists(meshlink_handle_t *mesh) { + if(!mesh->confbase) { + return false; + } - if(strcasecmp(found->variable, variable)) - return NULL; + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - return found; + return access(path, F_OK) == 0; } -config_t *lookup_config_next(splay_tree_t *config_tree, const config_t *cfg) { - splay_node_t *node; - config_t *found; +/// Lock the main configuration file. +bool main_config_lock(meshlink_handle_t *mesh) { + if(!mesh->confbase) { + return true; + } - cp(); + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - node = splay_search_node(config_tree, cfg); + mesh->conffile = fopen(path, "r"); - if(node) { - if(node->next) { - found = node->next->data; + if(!mesh->conffile) { + logger(NULL, MESHLINK_ERROR, "Cannot not open %s: %s\n", path, strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + return false; + } - if(!strcasecmp(found->variable, cfg->variable)) - return found; - } +#ifdef FD_CLOEXEC + fcntl(fileno(mesh->conffile), F_SETFD, FD_CLOEXEC); +#endif + +#ifdef HAVE_MINGW + // TODO: use _locking()? +#else + + if(flock(fileno(mesh->conffile), LOCK_EX | LOCK_NB) != 0) { + logger(NULL, MESHLINK_ERROR, "Cannot lock %s: %s\n", path, strerror(errno)); + fclose(mesh->conffile); + mesh->conffile = NULL; + meshlink_errno = MESHLINK_EBUSY; + return false; } - return NULL; +#endif + + return true; } -bool get_config_bool(const config_t *cfg, bool *result) { - cp(); +/// Unlock the main configuration file. +void main_config_unlock(meshlink_handle_t *mesh) { + if(mesh->conffile) { + fclose(mesh->conffile); + mesh->conffile = NULL; + } +} - if(!cfg) +/// Read a configuration file from a FILE handle. +bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config) { + if(!mesh->confbase) { return false; + } - if(!strcasecmp(cfg->value, "yes")) { - *result = true; - return true; - } else if(!strcasecmp(cfg->value, "no")) { - *result = false; - return true; + (void)mesh; + long len; + + if(fseek(f, 0, SEEK_END) || !(len = ftell(f)) || fseek(f, 0, SEEK_SET)) { + logger(mesh, MESHLINK_ERROR, "Cannot get config file size: %s\n", strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + fclose(f); + return false; } - logger(LOG_ERR, _("\"yes\" or \"no\" expected for configuration variable %s in %s line %d"), - cfg->variable, cfg->file, cfg->line); + uint8_t *buf = xmalloc(len); - return false; + if(fread(buf, len, 1, f) != 1) { + logger(mesh, MESHLINK_ERROR, "Cannot read config file: %s\n", strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + fclose(f); + return false; + } + + if(mesh->config_key) { + uint8_t *decrypted = xmalloc(len); + size_t decrypted_len = len; + chacha_poly1305_ctx_t *ctx = chacha_poly1305_init(); + chacha_poly1305_set_key(ctx, mesh->config_key); + + if(len > 12 && chacha_poly1305_decrypt_iv96(ctx, buf, buf + 12, len - 12, decrypted, &decrypted_len)) { + chacha_poly1305_exit(ctx); + free(buf); + config->buf = decrypted; + config->len = decrypted_len; + return true; + } else { + logger(mesh, MESHLINK_ERROR, "Cannot decrypt config file\n"); + meshlink_errno = MESHLINK_ESTORAGE; + chacha_poly1305_exit(ctx); + free(decrypted); + free(buf); + return false; + } + } + + config->buf = buf; + config->len = len; + + return true; } -bool get_config_int(const config_t *cfg, int *result) { - cp(); +/// Write a configuration file to a FILE handle. +bool config_write_file(meshlink_handle_t *mesh, FILE *f, const config_t *config) { + if(!mesh->confbase) { + return true; + } + + if(mesh->config_key) { + uint8_t buf[config->len + 16]; + size_t len = sizeof(buf); + uint8_t seqbuf[12]; + randomize(&seqbuf, sizeof(seqbuf)); + chacha_poly1305_ctx_t *ctx = chacha_poly1305_init(); + chacha_poly1305_set_key(ctx, mesh->config_key); + bool success = false; + + if(chacha_poly1305_encrypt_iv96(ctx, seqbuf, config->buf, config->len, buf, &len)) { + success = fwrite(seqbuf, sizeof(seqbuf), 1, f) == 1 && fwrite(buf, len, 1, f) == 1; + } else { + logger(mesh, MESHLINK_ERROR, "Cannot encrypt config file\n"); + meshlink_errno = MESHLINK_ESTORAGE; + } + + chacha_poly1305_exit(ctx); + return success; + } - if(!cfg) + if(fwrite(config->buf, config->len, 1, f) != 1) { + logger(mesh, MESHLINK_ERROR, "Cannot write config file: %s", strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; return false; + } - if(sscanf(cfg->value, "%d", result) == 1) - return true; + return true; +} + +/// Free resources of a loaded configuration file. +void config_free(config_t *config) { + free((uint8_t *)config->buf); + config->buf = NULL; + config->len = 0; +} - logger(LOG_ERR, _("Integer expected for configuration variable %s in %s line %d"), - cfg->variable, cfg->file, cfg->line); +/// Check the presence of a host configuration file. +bool config_exists(meshlink_handle_t *mesh, const char *name) { + if(!mesh->confbase) { + return false; + } - return false; + char path[PATH_MAX]; + make_host_path(mesh, name, path, sizeof(path)); + + return access(path, F_OK) == 0; } -bool get_config_string(const config_t *cfg, char **result) { - cp(); +/// Read a host configuration file. +bool config_read(meshlink_handle_t *mesh, const char *name, config_t *config) { + if(!mesh->confbase) { + return false; + } + + char path[PATH_MAX]; + make_host_path(mesh, name, path, sizeof(path)); + + FILE *f = fopen(path, "r"); - if(!cfg) + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); return false; + } - *result = xstrdup(cfg->value); + if(!config_read_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } + fclose(f); return true; } -bool get_config_address(const config_t *cfg, struct addrinfo **result) { - struct addrinfo *ai; +void config_scan_all(meshlink_handle_t *mesh, config_scan_action_t action) { + if(!mesh->confbase) { + return; + } - cp(); + DIR *dir; + struct dirent *ent; + char dname[PATH_MAX]; + make_host_path(mesh, "", dname, sizeof(dname)); - if(!cfg) - return false; + dir = opendir(dname); + + if(!dir) { + logger(mesh, MESHLINK_ERROR, "Could not open %s: %s", dname, strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + return; + } + + while((ent = readdir(dir))) { + action(mesh, ent->d_name); + } - ai = str2addrinfo(cfg->value, NULL, 0); + closedir(dir); +} - if(ai) { - *result = ai; +/// Write a host configuration file. +bool config_write(meshlink_handle_t *mesh, const char *name, const config_t *config) { + if(!mesh->confbase) { return true; } - logger(LOG_ERR, _("Hostname or IP address expected for configuration variable %s in %s line %d"), - cfg->variable, cfg->file, cfg->line); + char path[PATH_MAX]; + make_host_path(mesh, name, path, sizeof(path)); + + FILE *f = fopen(path, "w"); + + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; + } - return false; + if(!config_write_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } + + fclose(f); + return true; } -bool get_config_subnet(const config_t *cfg, subnet_t ** result) { - subnet_t subnet = {0}; +/// Read the main configuration file. +bool main_config_read(meshlink_handle_t *mesh, config_t *config) { + if(!mesh->confbase) { + return false; + } + + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - cp(); + FILE *f = fopen(path, "r"); - if(!cfg) + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); 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); + if(!config_read_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno)); + fclose(f); return false; } - /* Teach newbies what subnets are... */ + fclose(f); + return true; +} + +/// Write the main configuration file. +bool main_config_write(meshlink_handle_t *mesh, const config_t *config) { + if(!mesh->confbase) { + return true; + } + + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - if(((subnet.type == SUBNET_IPV4) - && !maskcheck(&subnet.net.ipv4.address, subnet.net.ipv4.prefixlength, sizeof subnet.net.ipv4.address)) - || ((subnet.type == SUBNET_IPV6) - && !maskcheck(&subnet.net.ipv6.address, subnet.net.ipv6.prefixlength, sizeof subnet.net.ipv6.address))) { - 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); + FILE *f = fopen(path, "w"); + + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); return false; } - *(*result = new_subnet()) = subnet; + if(!config_write_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } + fclose(f); return true; } -/* - 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. -*/ -static 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 && buflen) { - 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) { /* EOF or error */ - if(feof(fp)) - break; - - /* otherwise: error; let the calling function print an error message if applicable */ - free(line); - return NULL; - } +/// Read an invitation file, and immediately delete it. +bool invitation_read(meshlink_handle_t *mesh, const char *name, config_t *config) { + if(!mesh->confbase) { + return false; + } - newline = strchr(p, '\n'); + char path[PATH_MAX]; + char used_path[PATH_MAX]; + make_invitation_path(mesh, name, path, sizeof(path)); + make_used_invitation_path(mesh, name, used_path, sizeof(used_path)); - 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; + // Atomically rename the invitation file + if(rename(path, used_path)) { + if(errno == ENOENT) { + logger(mesh, MESHLINK_ERROR, "Peer tried to use non-existing invitation %s\n", name); } else { - *newline = '\0'; /* kill newline */ - if(newline > p && newline[-1] == '\r') /* and carriage return if necessary */ - newline[-1] = '\0'; - break; /* yay */ + logger(mesh, MESHLINK_ERROR, "Error trying to rename invitation %s\n", name); } + + return false; } - if(buf && buflen) { - *buflen = size; - *buf = line; + FILE *f = fopen(used_path, "r"); + + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; } - return line; -} + // Check the timestamp + struct stat st; -/* - Parse a configuration file and put the results in the configuration tree - starting at *base. -*/ -int read_config_file(splay_tree_t *config_tree, const char *fname) { - int err = -2; /* Parse error */ - FILE *fp; - char *buffer, *line; - char *variable, *value, *eol; - int lineno = 0; - int len; - bool ignore = false; - config_t *cfg; - size_t bufsize; - - cp(); - - fp = fopen(fname, "r"); - - if(!fp) { - logger(LOG_ERR, _("Cannot open config file %s: %s"), fname, - strerror(errno)); - return -3; - } - - bufsize = 100; - buffer = xmalloc(bufsize); - - for(;;) { - if(feof(fp)) { - err = 0; - break; - } + if(fstat(fileno(f), &st)) { + logger(mesh, MESHLINK_ERROR, "Could not stat invitation file %s\n", name); + fclose(f); + unlink(used_path); + return false; + } - line = readline(fp, &buffer, &bufsize); + if(time(NULL) > st.st_mtime + mesh->invitation_timeout) { + logger(mesh, MESHLINK_ERROR, "Peer tried to use an outdated invitation file %s\n", name); + fclose(f); + unlink(used_path); + return false; + } - if(!line) { - err = -1; - break; - } + if(!config_read_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno)); + fclose(f); + unlink(used_path); + return false; + } - lineno++; + fclose(f); + unlink(used_path); + return true; +} - if(!*line || *line == '#') - continue; +/// Write an invitation file. +bool invitation_write(meshlink_handle_t *mesh, const char *name, const config_t *config) { + if(!mesh->confbase) { + return true; + } - if(ignore) { - if(!strncmp(line, "-----END", 8)) - ignore = false; - continue; - } - - if(!strncmp(line, "-----BEGIN", 10)) { - ignore = true; - continue; - } + char path[PATH_MAX]; + make_invitation_path(mesh, name, path, sizeof(path)); + + FILE *f = fopen(path, "w"); - variable = value = line; + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; + } - eol = line + strlen(line); - while(strchr("\t ", *--eol)) - *eol = '\0'; + if(!config_write_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } - len = strcspn(value, "\t ="); - value += len; - value += strspn(value, "\t "); - if(*value == '=') { - value++; - value += strspn(value, "\t "); - } - variable[len] = '\0'; + fclose(f); + return true; +} - - if(!*value) { - logger(LOG_ERR, _("No value for variable `%s' on line %d while reading config file %s"), - variable, lineno, fname); - break; - } +/// Purge old invitation files +size_t invitation_purge_old(meshlink_handle_t *mesh, time_t deadline) { + if(!mesh->confbase) { + return true; + } - cfg = new_config(); - cfg->variable = xstrdup(variable); - cfg->value = xstrdup(value); - cfg->file = xstrdup(fname); - cfg->line = lineno; + char path[PATH_MAX]; + make_invitation_path(mesh, "", path, sizeof(path)); - config_add(config_tree, cfg); + DIR *dir = opendir(path); + + if(!dir) { + logger(mesh, MESHLINK_DEBUG, "Could not read directory %s: %s\n", path, strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + return 0; } - free(buffer); - fclose(fp); + errno = 0; + size_t count = 0; + struct dirent *ent; - return err; -} + while((ent = readdir(dir))) { + if(strlen(ent->d_name) != 24) { + continue; + } -bool read_server_config() { - char *fname; - int x; + char invname[PATH_MAX]; + struct stat st; - cp(); + if(snprintf(invname, sizeof(invname), "%s" SLASH "%s", path, ent->d_name) >= PATH_MAX) { + logger(mesh, MESHLINK_DEBUG, "Filename too long: %s" SLASH "%s", path, ent->d_name); + continue; + } - xasprintf(&fname, "%s/tinc.conf", confbase); - x = read_config_file(config_tree, fname); + if(!stat(invname, &st)) { + if(mesh->invitation_key && deadline < st.st_mtime) { + count++; + } else { + unlink(invname); + } + } else { + logger(mesh, MESHLINK_DEBUG, "Could not stat %s: %s\n", invname, strerror(errno)); + errno = 0; + } + } - if(x == -1) { /* System error: complain */ - logger(LOG_ERR, _("Failed to read `%s': %s"), fname, strerror(errno)); + if(errno) { + logger(mesh, MESHLINK_DEBUG, "Error while reading directory %s: %s\n", path, strerror(errno)); + closedir(dir); + meshlink_errno = MESHLINK_ESTORAGE; + return 0; } - free(fname); + closedir(dir); - return x == 0; + return count; }