X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fconf.c;h=9e93c9a168a511b886fc2edbbddaaeddcfd5e362;hb=fa05f996c5500c056a36c1d43e33a407f876643c;hp=c5c3264e655d5d696d2296314685f06691d87924;hpb=0bdce44687a22c8825695cba185b845f5ea5e060;p=meshlink diff --git a/src/conf.c b/src/conf.c index c5c3264e..9e93c9a1 100644 --- a/src/conf.c +++ b/src/conf.c @@ -1,6 +1,6 @@ /* - conf.c -- configuration code - Copyright (C) 2014 Guus Sliepen + 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 @@ -20,473 +20,472 @@ #include "system.h" #include -#include "splay_tree.h" -#include "connection.h" #include "conf.h" -#include "list.h" +#include "crypto.h" #include "logger.h" #include "meshlink_internal.h" -#include "netutl.h" /* for str2address */ -#include "protocol.h" -#include "utils.h" /* for cp */ #include "xalloc.h" +#include "packmsg.h" -static int config_compare(const config_t *a, const config_t *b) { - int result; - - result = strcasecmp(a->variable, b->variable); - - if(result) - return result; - - result = a->line - b->line; - - if(result) - return result; - else - return a->file ? strcmp(a->file, b->file) : 0; +/// 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); } -void init_configuration(splay_tree_t **config_tree) { - *config_tree = splay_alloc_tree((splay_compare_t) config_compare, (splay_action_t) free_config); +/// 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); } -void exit_configuration(splay_tree_t **config_tree) { - if(*config_tree) - splay_delete_tree(*config_tree); - *config_tree = NULL; +/// 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); } -config_t *new_config(void) { - return xzalloc(sizeof(config_t)); +/// 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); } -void free_config(config_t *cfg) { - if(cfg->variable) - free(cfg->variable); - - if(cfg->value) - free(cfg->value); +/// Remove a directory recursively +static void deltree(const char *dirname) { + DIR *d = opendir(dirname); - if(cfg->file) - free(cfg->file); - - free(cfg); -} - -void config_add(splay_tree_t *config_tree, config_t *cfg) { - splay_insert(config_tree, cfg); -} + if(d) { + struct dirent *ent; -config_t *lookup_config(splay_tree_t *config_tree, char *variable) { - config_t cfg, *found; - - cfg.variable = variable; - cfg.file = NULL; - cfg.line = 0; + while((ent = readdir(d))) { + if(ent->d_name[0] == '.') { + continue; + } - found = splay_search_closest_greater(config_tree, &cfg); + char filename[PATH_MAX]; + snprintf(filename, sizeof(filename), "%s" SLASH "%s", dirname, ent->d_name); - if(!found) - return NULL; + if(unlink(filename)) { + deltree(filename); + } + } - if(strcasecmp(found->variable, variable)) - return NULL; + closedir(d); + } - return found; + rmdir(dirname); } -config_t *lookup_config_next(splay_tree_t *config_tree, const config_t *cfg) { - splay_node_t *node; - config_t *found; +/// Create a fresh configuration directory +bool config_init(meshlink_handle_t *mesh) { + if(mkdir(mesh->confbase, 0700) && errno != EEXIST) { + logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", mesh->confbase, strerror(errno)); + return false; + } - node = splay_search_node(config_tree, cfg); + char path[PATH_MAX]; - if(node) { - if(node->next) { - found = node->next->data; + // Remove meshlink.conf + snprintf(path, sizeof(path), "%s" SLASH "meshlink.conf", mesh->confbase); + unlink(path); - if(!strcasecmp(found->variable, cfg->variable)) - return found; - } + // Remove any host config files + snprintf(path, sizeof(path), "%s" SLASH "hosts", mesh->confbase); + deltree(path); + + if(mkdir(path, 0700) && errno != EEXIST) { + logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno)); + return false; } - return NULL; -} + // Remove any invitation files + snprintf(path, sizeof(path), "%s" SLASH "invitations", mesh->confbase); + deltree(path); -bool get_config_bool(const config_t *cfg, bool *result) { - if(!cfg) + if(mkdir(path, 0700) && errno != EEXIST) { + logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno)); return false; - - if(!strcasecmp(cfg->value, "yes")) { - *result = true; - return true; - } else if(!strcasecmp(cfg->value, "no")) { - *result = false; - return true; } - logger(NULL, MESHLINK_ERROR, "\"yes\" or \"no\" expected for configuration variable %s in %s line %d", - cfg->variable, cfg->file, cfg->line); - - return false; + return true; } -bool get_config_int(const config_t *cfg, int *result) { - if(!cfg) - return false; +/// Wipe an existing configuration directory +bool config_destroy(const char *confbase) { + char path[PATH_MAX]; + + // Remove meshlink.conf + snprintf(path, sizeof(path), "%s" SLASH "meshlink.conf", confbase); + + 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; + } + } - if(sscanf(cfg->value, "%d", result) == 1) - return true; + deltree(confbase); + return true; +} - logger(NULL, MESHLINK_ERROR, "Integer expected for configuration variable %s in %s line %d", - cfg->variable, cfg->file, cfg->line); +/// Check the presence of the main configuration file. +bool main_config_exists(meshlink_handle_t *mesh) { + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - return false; + return access(path, F_OK) == 0; } -bool set_config_int(config_t *cfg, int val) { - if(!cfg) - return false; +/// Lock the main configuration file. +bool main_config_lock(meshlink_handle_t *mesh) { + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - char val_str[1024]; - snprintf(val_str, sizeof(val_str), "%d", val); + mesh->conffile = fopen(path, "r"); - if(cfg->value) - free(cfg->value); + if(!mesh->conffile) { + logger(NULL, MESHLINK_ERROR, "Cannot not open %s: %s\n", path, strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + return false; + } - cfg->value = xstrdup(val_str); +#ifdef FD_CLOEXEC + fcntl(fileno(mesh->conffile), F_SETFD, FD_CLOEXEC); +#endif - return true; -} +#ifdef HAVE_MINGW + // TODO: use _locking()? +#else -bool get_config_string(const config_t *cfg, char **result) { - if(!cfg) + 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; + } - *result = xstrdup(cfg->value); +#endif return true; } -bool set_config_string(config_t *cfg, const char *val) { - if(!cfg) - return false; - - if(cfg->value) - free(cfg->value); - - cfg->value = xstrdup(val); - - return true; +/// Unlock the main configuration file. +void main_config_unlock(meshlink_handle_t *mesh) { + if(mesh->conffile) { + fclose(mesh->conffile); + mesh->conffile = NULL; + } } -bool get_config_address(const config_t *cfg, struct addrinfo **result) { - struct addrinfo *ai; +/// Read a configuration file from a FILE handle. +bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config) { + (void)mesh; + long len; - if(!cfg) + 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; + } - ai = str2addrinfo(cfg->value, NULL, 0); + uint8_t *buf = xmalloc(len); - if(ai) { - *result = ai; - return true; + 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; } - logger(NULL, MESHLINK_ERROR, "Hostname or IP address expected for configuration variable %s in %s line %d", - cfg->variable, cfg->file, cfg->line); + 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)) { + 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; + free(decrypted); + free(buf); + return false; + } + } - return false; -} + config->buf = buf; + config->len = len; -/* - Read exactly one line and strip the trailing newline if any. -*/ -static char *readline(FILE *fp, char *buf, size_t buflen) { - char *newline = NULL; - char *p; + return true; +} - if(feof(fp)) - return NULL; +/// Write a configuration file to a FILE handle. +bool config_write_file(meshlink_handle_t *mesh, FILE *f, const config_t *config) { + 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; + } - p = fgets(buf, buflen, fp); + chacha_poly1305_exit(ctx); + return success; + } - if(!p) - return NULL; + 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; + } - newline = strchr(p, '\n'); + return true; +} - if(!newline) - return buf; +/// Free resources of a loaded configuration file. +void config_free(config_t *config) { + free((uint8_t *)config->buf); + config->buf = NULL; + config->len = 0; +} - /* kill newline and carriage return if necessary */ - *newline = '\0'; - if(newline > p && newline[-1] == '\r') - newline[-1] = '\0'; +/// Check the presence of a host configuration file. +bool config_exists(meshlink_handle_t *mesh, const char *name) { + char path[PATH_MAX]; + make_host_path(mesh, name, path, sizeof(path)); - return buf; + return access(path, F_OK) == 0; } -config_t *parse_config_line(char *line, const char *fname, int lineno) { - config_t *cfg; - int len; - char *variable, *value, *eol; - variable = value = line; - - eol = line + strlen(line); - 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'; +/// Read a host configuration file. +bool config_read(meshlink_handle_t *mesh, const char *name, config_t *config) { + char path[PATH_MAX]; + make_host_path(mesh, name, path, sizeof(path)); + + FILE *f = fopen(path, "r"); - if(!*value) { - const char err[] = "No value for variable"; - logger(NULL, MESHLINK_ERROR, "%s `%s' on line %d while reading config file %s", - err, variable, lineno, fname); - return NULL; + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; } - cfg = new_config(); - cfg->variable = xstrdup(variable); - cfg->value = xstrdup(value); - cfg->file = xstrdup(fname); - cfg->line = lineno; + if(!config_read_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } - return cfg; + fclose(f); + return true; } -/* - Parse a configuration file and put the results in the configuration tree - starting at *base. -*/ -bool read_config_file(splay_tree_t *config_tree, const char *fname) { - FILE *fp; - char buffer[MAX_STRING_SIZE]; - char *line; - int lineno = 0; - bool ignore = false; - config_t *cfg; - bool result = false; - - fp = fopen(fname, "r"); - - if(!fp) { - logger(NULL, MESHLINK_ERROR, "Cannot open config file %s: %s", fname, strerror(errno)); - return false; - } +/// Write a host configuration file. +bool config_write(meshlink_handle_t *mesh, const char *name, const config_t *config) { + char path[PATH_MAX]; + make_host_path(mesh, name, path, sizeof(path)); - for(;;) { - line = readline(fp, buffer, sizeof(buffer)); + FILE *f = fopen(path, "w"); - if(!line) { - if(feof(fp)) - result = true; - break; - } + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; + } - lineno++; + if(!config_write_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } - if(!*line || *line == '#') - continue; + fclose(f); + return true; +} - if(ignore) { - if(!strncmp(line, "-----END", 8)) - ignore = false; - continue; - } +/// Read the main configuration file. +bool main_config_read(meshlink_handle_t *mesh, config_t *config) { + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - if(!strncmp(line, "-----BEGIN", 10)) { - ignore = true; - continue; - } + FILE *f = fopen(path, "r"); - cfg = parse_config_line(line, fname, lineno); - if(!cfg) - break; - config_add(config_tree, cfg); + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; } - fclose(fp); + if(!config_read_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno)); + fclose(f); + return false; + } - return result; + fclose(f); + return true; } -bool write_config_file(const struct splay_tree_t *config_tree, const char *fname) { - FILE *fp; +/// Write the main configuration file. +bool main_config_write(meshlink_handle_t *mesh, const config_t *config) { + char path[PATH_MAX]; + make_main_path(mesh, path, sizeof(path)); - fp = fopen(fname, "w+"); + FILE *f = fopen(path, "w"); - if(!fp) { - logger(NULL, MESHLINK_ERROR, "Cannot open config file %s: %s", fname, strerror(errno)); + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); return false; } - for splay_each(config_t, cnf, config_tree) { - if(fwrite(cnf->variable, sizeof(char), strlen(cnf->variable), fp) < strlen(cnf->variable)) - goto error; - - if(fwrite(" = ", sizeof(char), 3, fp) < 3) - goto error; - - if(fwrite(cnf->value, sizeof(char), strlen(cnf->value), fp) < strlen(cnf->value)) - goto error; - - if(fwrite("\n", sizeof(char), 1, fp) < 1) - goto error; + if(!config_write_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno)); + fclose(f); + return false; } - fclose(fp); + fclose(f); return true; - -error: - logger(NULL, MESHLINK_ERROR, "Cannot write to config file %s: %s", fname, strerror(errno)); - fclose(fp); - return false; } -bool read_server_config(meshlink_handle_t *mesh) { - char filename[PATH_MAX]; - bool x; +/// Read an invitation file, and immediately delete it. +bool invitation_read(meshlink_handle_t *mesh, const char *name, config_t *config) { + 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)); + + // 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 { + logger(mesh, MESHLINK_ERROR, "Error trying to rename invitation %s\n", name); + } - snprintf(filename, PATH_MAX, "%s" SLASH "meshlink.conf", mesh->confbase); - errno = 0; - x = read_config_file(mesh->config, filename); + return false; + } - if(!x && errno) - logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", filename, strerror(errno)); + FILE *f = fopen(used_path, "r"); - return x; -} + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); + return false; + } -bool read_host_config(meshlink_handle_t *mesh, splay_tree_t *config_tree, const char *name) { - char filename[PATH_MAX]; - bool x; + // Check the timestamp + struct stat st; - snprintf(filename, PATH_MAX, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name); - x = read_config_file(config_tree, filename); + if(fstat(fileno(f), &st)) { + logger(mesh, MESHLINK_ERROR, "Could not stat invitation file %s\n", name); + fclose(f); + unlink(used_path); + return false; + } - return x; -} + 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; + } -bool write_host_config(struct meshlink_handle *mesh, const struct splay_tree_t *config_tree, const char *name) { - char filename[PATH_MAX]; + 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; + } - snprintf(filename, PATH_MAX, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name); - return write_config_file(config_tree, filename); + fclose(f); + unlink(used_path); + return true; } -bool modify_config_file(struct meshlink_handle *mesh, const char *name, const char *key, const char *value, bool replace) { - assert(mesh && name && key && (replace || value)); +/// Write an invitation file. +bool invitation_write(meshlink_handle_t *mesh, const char *name, const config_t *config) { + char path[PATH_MAX]; + make_invitation_path(mesh, name, path, sizeof(path)); - char filename[PATH_MAX]; - char tmpname[PATH_MAX]; - bool error = false; + FILE *f = fopen(path, "w"); - snprintf(filename, sizeof(filename), "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name); - snprintf(tmpname, sizeof(tmpname), "%s.tmp", filename); - - FILE *fr = fopen(filename, "r"); - - if(!fr) { - logger(mesh, MESHLINK_ERROR, "Cannot open config file %s: %s", filename, strerror(errno)); + if(!f) { + logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno)); return false; } - FILE *fw = fopen(tmpname, "w"); - - if(!fw) { - logger(mesh, MESHLINK_ERROR, "Cannot open temporary file %s: %s", tmpname, strerror(errno)); - fclose(fr); + if(!config_write_file(mesh, f, config)) { + logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno)); + fclose(f); return false; } - char buf[4096]; - char *sep; - bool found = false; + fclose(f); + return true; +} - while(readline(fr, buf, sizeof(buf))) { - if(!*buf || *buf == '#') - goto copy; +/// Purge old invitation files +size_t invitation_purge_old(meshlink_handle_t *mesh, time_t deadline) { + char path[PATH_MAX]; + make_invitation_path(mesh, "", path, sizeof(path)); - sep = strchr(buf, ' '); - if(!sep) - goto copy; + DIR *dir = opendir(path); - *sep = 0; - if(strcmp(buf, key)) { - *sep = ' '; - goto copy; - } + if(!dir) { + logger(mesh, MESHLINK_DEBUG, "Could not read directory %s: %s\n", path, strerror(errno)); + meshlink_errno = MESHLINK_ESTORAGE; + return 0; + } + + errno = 0; + size_t count = 0; + struct dirent *ent; - if(!value) { - found = true; + while((ent = readdir(dir))) { + if(strlen(ent->d_name) != 24) { continue; } - // We found the key and the value. Keep one copy around. - if(sep[1] == '=' && sep[2] == ' ' && !strcmp(sep + 3, value)) { - if(found) - continue; - found = true; - } + char invname[PATH_MAX]; + struct stat st; - // We found the key but with a different value, delete it if wanted. - if(!found && replace) + 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; + } - *sep = ' '; - -copy: - fprintf(fw, "%s\n", buf); + 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(ferror(fr)) - error = true; - - fclose(fr); - - // Add new key/value pair if necessary - if(!found && value) - fprintf(fw, "%s = %s\n", key, value); - - if(ferror(fw)) - error = true; - - if(fclose(fw)) - error = true; - - // If any error occured during reading or writing, exit. - if(error) { - unlink(tmpname); - return false; + if(errno) { + logger(mesh, MESHLINK_DEBUG, "Error while reading directory %s: %s\n", path, strerror(errno)); + closedir(dir); + meshlink_errno = MESHLINK_ESTORAGE; + return 0; } - // Try to atomically replace the old config file with the new one. -#ifdef HAVE_MINGW - char bakname[PATH_MAX]; - snprintf(bakname, sizeof(bakname), "%s.bak", filename); - if(rename(filename, bakname) || rename(tmpname, filename)) { - rename(bakname, filename); -#else - if(rename(tmpname, filename)) { -#endif - return false; - } else { -#ifdef HAVE_MINGW - unlink(bakname); -#endif - return true; - } -} + closedir(dir); -bool append_config_file(meshlink_handle_t *mesh, const char *name, const char *key, const char *value) { - return modify_config_file(mesh, name, key, value, false); + return count; }