]> git.meshlink.io Git - meshlink/blobdiff - src/conf.c
Move assert()s that dereference a pointer to after the pointer NULL check.
[meshlink] / src / conf.c
index 9e93c9a168a511b886fc2edbbddaaeddcfd5e362..9527c1edf5c13cda07db36b6255ec4ee777b078e 100644 (file)
@@ -19,6 +19,8 @@
 
 #include "system.h"
 #include <assert.h>
+#include <sys/types.h>
+#include <utime.h>
 
 #include "conf.h"
 #include "crypto.h"
 #include "packmsg.h"
 
 /// 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);
+static void make_main_path(meshlink_handle_t *mesh, const char *conf_subdir, char *path, size_t len) {
+       assert(conf_subdir);
+       assert(path);
+       assert(len);
+
+       snprintf(path, len, "%s" SLASH "%s" SLASH "meshlink.conf", mesh->confbase, conf_subdir);
 }
 
 /// 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 void make_host_path(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, char *path, size_t len) {
+       assert(conf_subdir);
+       assert(name);
+       assert(path);
+       assert(len);
+
+       snprintf(path, len, "%s" SLASH "%s" SLASH "hosts" SLASH "%s", mesh->confbase, conf_subdir, name);
 }
 
 /// 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);
+static void make_invitation_path(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, char *path, size_t len) {
+       assert(conf_subdir);
+       assert(name);
+       assert(path);
+       assert(len);
+
+       snprintf(path, len, "%s" SLASH "%s" SLASH "invitations" SLASH "%s", mesh->confbase, conf_subdir, name);
 }
 
 /// 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);
+static void make_used_invitation_path(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, char *path, size_t len) {
+       assert(conf_subdir);
+       assert(name);
+       assert(path);
+       assert(len);
+
+       snprintf(path, len, "%s" SLASH "%s" SLASH "invitations" SLASH "%s.used", mesh->confbase, conf_subdir, name);
 }
 
 /// Remove a directory recursively
-static void deltree(const char *dirname) {
+static bool deltree(const char *dirname) {
+       assert(dirname);
+
        DIR *d = opendir(dirname);
 
        if(d) {
@@ -63,43 +86,102 @@ static void deltree(const char *dirname) {
                        snprintf(filename, sizeof(filename), "%s" SLASH "%s", dirname, ent->d_name);
 
                        if(unlink(filename)) {
-                               deltree(filename);
+                               if(!deltree(filename)) {
+                                       return false;
+                               }
                        }
                }
 
                closedir(d);
+       } else {
+               return errno == ENOENT;
        }
 
-       rmdir(dirname);
+       return rmdir(dirname) == 0;
 }
 
-/// 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));
+bool sync_path(const char *pathname) {
+       assert(pathname);
+
+       int fd = open(pathname, O_RDONLY);
+
+       if(fd < 0) {
+               logger(NULL, MESHLINK_ERROR, "Failed to open %s: %s\n", pathname, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
                return false;
        }
 
+       if(fsync(fd)) {
+               logger(NULL, MESHLINK_ERROR, "Failed to sync %s: %s\n", pathname, strerror(errno));
+               close(fd);
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       if(close(fd)) {
+               logger(NULL, MESHLINK_ERROR, "Failed to close %s: %s\n", pathname, strerror(errno));
+               close(fd);
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       return true;
+}
+
+/// Try decrypting the main configuration file from the given sub-directory.
+static bool main_config_decrypt(meshlink_handle_t *mesh, const char *conf_subdir) {
+       assert(mesh->config_key);
+       assert(mesh->confbase);
+       assert(conf_subdir);
+
+       config_t config;
+
+       if(!main_config_read(mesh, conf_subdir, &config, mesh->config_key)) {
+               logger(mesh, MESHLINK_ERROR, "Could not read main configuration file");
+               return false;
+       }
+
+       packmsg_input_t in = {config.buf, config.len};
+
+       uint32_t version = packmsg_get_uint32(&in);
+       config_free(&config);
+
+       return version == MESHLINK_CONFIG_VERSION;
+}
+
+/// Create a fresh configuration directory
+bool config_init(meshlink_handle_t *mesh, const char *conf_subdir) {
+       assert(conf_subdir);
+
+       if(!mesh->confbase) {
+               return true;
+       }
+
        char path[PATH_MAX];
 
-       // Remove meshlink.conf
-       snprintf(path, sizeof(path), "%s" SLASH "meshlink.conf", mesh->confbase);
-       unlink(path);
+       // Create "current" sub-directory in the confbase
+       snprintf(path, sizeof(path), "%s" SLASH "%s", mesh->confbase, conf_subdir);
+
+       if(!deltree(path)) {
+               logger(mesh, MESHLINK_DEBUG, "Could not delete directory %s: %s\n", path, strerror(errno));
+               return false;
+       }
+
+       if(mkdir(path, 0700)) {
+               logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno));
+               return false;
+       }
 
-       // Remove any host config files
-       snprintf(path, sizeof(path), "%s" SLASH "hosts", mesh->confbase);
-       deltree(path);
+       make_host_path(mesh, conf_subdir, "", path, sizeof(path));
 
-       if(mkdir(path, 0700) && errno != EEXIST) {
+       if(mkdir(path, 0700)) {
                logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno));
                return false;
        }
 
-       // Remove any invitation files
-       snprintf(path, sizeof(path), "%s" SLASH "invitations", mesh->confbase);
-       deltree(path);
+       make_invitation_path(mesh, conf_subdir, "", path, sizeof(path));
 
-       if(mkdir(path, 0700) && errno != EEXIST) {
+       if(mkdir(path, 0700)) {
                logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", path, strerror(errno));
                return false;
        }
@@ -108,60 +190,333 @@ bool config_init(meshlink_handle_t *mesh) {
 }
 
 /// Wipe an existing configuration directory
-bool config_destroy(const char *confbase) {
+bool config_destroy(const char *confbase, const char *conf_subdir) {
+       assert(conf_subdir);
+
+       if(!confbase) {
+               return true;
+       }
+
+       struct stat st;
+
        char path[PATH_MAX];
 
-       // Remove meshlink.conf
-       snprintf(path, sizeof(path), "%s" SLASH "meshlink.conf", confbase);
+       // Check the presence of configuration base sub directory.
+       snprintf(path, sizeof(path), "%s" SLASH "%s", confbase, conf_subdir);
 
-       if(unlink(path)) {
+       if(stat(path, &st)) {
                if(errno == ENOENT) {
-                       meshlink_errno = MESHLINK_ENOENT;
-                       return false;
+                       return true;
                } else {
+                       logger(NULL, MESHLINK_ERROR, "Cannot stat %s: %s\n", path, strerror(errno));
+                       meshlink_errno = MESHLINK_ESTORAGE;
+                       return false;
+               }
+       }
+
+       // Remove meshlink.conf
+       snprintf(path, sizeof(path), "%s" SLASH "%s" SLASH "meshlink.conf", confbase, conf_subdir);
+
+       if(unlink(path)) {
+               if(errno != ENOENT) {
                        logger(NULL, MESHLINK_ERROR, "Cannot delete %s: %s\n", path, strerror(errno));
                        meshlink_errno = MESHLINK_ESTORAGE;
                        return false;
                }
        }
 
-       deltree(confbase);
+       snprintf(path, sizeof(path), "%s" SLASH "%s", confbase, conf_subdir);
+
+       if(!deltree(path)) {
+               logger(NULL, MESHLINK_ERROR, "Cannot delete %s: %s\n", path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       return sync_path(confbase);
+}
+
+static bool copytree(const char *src_dir_name, const void *src_key, const char *dst_dir_name, const void *dst_key) {
+       assert(src_dir_name);
+       assert(dst_dir_name);
+
+       char src_filename[PATH_MAX];
+       char dst_filename[PATH_MAX];
+       struct dirent *ent;
+
+       DIR *src_dir = opendir(src_dir_name);
+
+       if(!src_dir) {
+               logger(NULL, MESHLINK_ERROR, "Could not open directory file %s\n", src_dir_name);
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       // Delete if already exists and create a new destination directory
+       if(!deltree(dst_dir_name)) {
+               logger(NULL, MESHLINK_ERROR, "Cannot delete %s: %s\n", dst_dir_name, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       if(mkdir(dst_dir_name, 0700)) {
+               logger(NULL, MESHLINK_ERROR, "Could not create directory %s\n", dst_filename);
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       while((ent = readdir(src_dir))) {
+               if(ent->d_name[0] == '.') {
+                       continue;
+               }
+
+               snprintf(dst_filename, sizeof(dst_filename), "%s" SLASH "%s", dst_dir_name, ent->d_name);
+               snprintf(src_filename, sizeof(src_filename), "%s" SLASH "%s", src_dir_name, ent->d_name);
+
+               if(ent->d_type == DT_DIR) {
+                       if(!copytree(src_filename, src_key, dst_filename, dst_key)) {
+                               logger(NULL, MESHLINK_ERROR, "Copying %s to %s failed\n", src_filename, dst_filename);
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       if(!sync_path(dst_filename)) {
+                               return false;
+                       }
+               } else if(ent->d_type == DT_REG) {
+                       struct stat st;
+                       config_t config;
+
+                       if(stat(src_filename, &st)) {
+                               logger(NULL, MESHLINK_ERROR, "Could not stat file `%s': %s\n", src_filename, strerror(errno));
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       FILE *f = fopen(src_filename, "r");
+
+                       if(!f) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to open `%s': %s\n", src_filename, strerror(errno));
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       if(!config_read_file(NULL, f, &config, src_key)) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to read `%s': %s\n", src_filename, strerror(errno));
+                               fclose(f);
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       if(fclose(f)) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to close `%s': %s\n", src_filename, strerror(errno));
+                               config_free(&config);
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       f = fopen(dst_filename, "w");
+
+                       if(!f) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to open `%s': %s", dst_filename, strerror(errno));
+                               config_free(&config);
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       if(!config_write_file(NULL, f, &config, dst_key)) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to write `%s': %s", dst_filename, strerror(errno));
+                               config_free(&config);
+                               fclose(f);
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       if(fclose(f)) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to close `%s': %s", dst_filename, strerror(errno));
+                               config_free(&config);
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+
+                       config_free(&config);
+
+                       struct utimbuf times;
+                       times.modtime = st.st_mtime;
+                       times.actime = st.st_atime;
+
+                       if(utime(dst_filename, &times)) {
+                               logger(NULL, MESHLINK_ERROR, "Failed to utime `%s': %s", dst_filename, strerror(errno));
+                               meshlink_errno = MESHLINK_ESTORAGE;
+                               return false;
+                       }
+               }
+       }
+
+       closedir(src_dir);
        return true;
 }
 
+bool config_copy(meshlink_handle_t *mesh, const char *src_dir_name, const void *src_key, const char *dst_dir_name, const void *dst_key) {
+       assert(src_dir_name);
+       assert(dst_dir_name);
+
+       char src_filename[PATH_MAX];
+       char dst_filename[PATH_MAX];
+
+       snprintf(dst_filename, sizeof(dst_filename), "%s" SLASH "%s", mesh->confbase, dst_dir_name);
+       snprintf(src_filename, sizeof(src_filename), "%s" SLASH "%s", mesh->confbase, src_dir_name);
+
+       return copytree(src_filename, src_key, dst_filename, dst_key);
+}
+
 /// 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));
+bool main_config_exists(meshlink_handle_t *mesh, const char *conf_subdir) {
+       assert(conf_subdir);
 
+       if(!mesh->confbase) {
+               return false;
+       }
+
+       char path[PATH_MAX];
+       make_main_path(mesh, conf_subdir, path, sizeof(path));
        return access(path, F_OK) == 0;
 }
 
-/// Lock the main configuration file.
+bool config_rename(meshlink_handle_t *mesh, const char *old_conf_subdir, const char *new_conf_subdir) {
+       assert(old_conf_subdir);
+       assert(new_conf_subdir);
+
+       if(!mesh->confbase) {
+               return false;
+       }
+
+       char old_path[PATH_MAX];
+       char new_path[PATH_MAX];
+
+       snprintf(old_path, sizeof(old_path), "%s" SLASH "%s", mesh->confbase, old_conf_subdir);
+       snprintf(new_path, sizeof(new_path), "%s" SLASH "%s", mesh->confbase, new_conf_subdir);
+
+       return rename(old_path, new_path) == 0 && sync_path(mesh->confbase);
+}
+
+bool config_sync(meshlink_handle_t *mesh, const char *conf_subdir) {
+       assert(conf_subdir);
+
+       if(!mesh->confbase) {
+               return true;
+       }
+
+       char path[PATH_MAX];
+       snprintf(path, sizeof(path), "%s" SLASH "%s" SLASH "hosts", mesh->confbase, conf_subdir);
+
+       if(!sync_path(path)) {
+               return false;
+       }
+
+       snprintf(path, sizeof(path), "%s" SLASH "%s", mesh->confbase, conf_subdir);
+
+       if(!sync_path(path)) {
+               return false;
+       }
+
+       return true;
+}
+
+bool meshlink_confbase_exists(meshlink_handle_t *mesh) {
+       if(!mesh->confbase) {
+               return false;
+       }
+
+       bool confbase_exists = false;
+       bool confbase_decryptable = false;
+
+       if(main_config_exists(mesh, "current")) {
+               confbase_exists = true;
+
+               if(mesh->config_key && main_config_decrypt(mesh, "current")) {
+                       confbase_decryptable = true;
+               }
+       }
+
+       if(mesh->config_key && !confbase_decryptable && main_config_exists(mesh, "new")) {
+               confbase_exists = true;
+
+               if(main_config_decrypt(mesh, "new")) {
+                       if(!config_destroy(mesh->confbase, "current")) {
+                               return false;
+                       }
+
+                       if(!config_rename(mesh, "new", "current")) {
+                               return false;
+                       }
+
+                       confbase_decryptable = true;
+               }
+       }
+
+       if(mesh->config_key && !confbase_decryptable && main_config_exists(mesh, "old")) {
+               confbase_exists = true;
+
+               if(main_config_decrypt(mesh, "old")) {
+                       if(!config_destroy(mesh->confbase, "current")) {
+                               return false;
+                       }
+
+                       if(!config_rename(mesh, "old", "current")) {
+                               return false;
+                       }
+
+                       confbase_decryptable = true;
+               }
+       }
+
+       // Cleanup if current is existing with old and new
+       if(confbase_exists && confbase_decryptable) {
+               if(!config_destroy(mesh->confbase, "old") || !config_destroy(mesh->confbase, "new")) {
+                       return false;
+               }
+       }
+
+       return confbase_exists;
+}
+
+/// Lock the main configuration file. Creates confbase if necessary.
 bool main_config_lock(meshlink_handle_t *mesh) {
+       if(!mesh->confbase) {
+               return true;
+       }
+
+       if(mkdir(mesh->confbase, 0700) && errno != EEXIST) {
+               logger(NULL, MESHLINK_ERROR, "Cannot create configuration directory %s: %s", mesh->confbase, strerror(errno));
+               meshlink_close(mesh);
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return NULL;
+       }
+
        char path[PATH_MAX];
-       make_main_path(mesh, path, sizeof(path));
+       snprintf(path, sizeof(path), "%s" SLASH "meshlink.lock", mesh->confbase);
 
-       mesh->conffile = fopen(path, "r");
+       mesh->lockfile = fopen(path, "w+");
 
-       if(!mesh->conffile) {
+       if(!mesh->lockfile) {
                logger(NULL, MESHLINK_ERROR, "Cannot not open %s: %s\n", path, strerror(errno));
                meshlink_errno = MESHLINK_ESTORAGE;
                return false;
        }
 
 #ifdef FD_CLOEXEC
-       fcntl(fileno(mesh->conffile), F_SETFD, FD_CLOEXEC);
+       fcntl(fileno(mesh->lockfile), F_SETFD, FD_CLOEXEC);
 #endif
 
 #ifdef HAVE_MINGW
        // TODO: use _locking()?
 #else
 
-       if(flock(fileno(mesh->conffile), LOCK_EX | LOCK_NB) != 0) {
+       if(flock(fileno(mesh->lockfile), LOCK_EX | LOCK_NB) != 0) {
                logger(NULL, MESHLINK_ERROR, "Cannot lock %s: %s\n", path, strerror(errno));
-               fclose(mesh->conffile);
-               mesh->conffile = NULL;
+               fclose(mesh->lockfile);
+               mesh->lockfile = NULL;
                meshlink_errno = MESHLINK_EBUSY;
                return false;
        }
@@ -173,21 +528,21 @@ bool main_config_lock(meshlink_handle_t *mesh) {
 
 /// Unlock the main configuration file.
 void main_config_unlock(meshlink_handle_t *mesh) {
-       if(mesh->conffile) {
-               fclose(mesh->conffile);
-               mesh->conffile = NULL;
+       if(mesh->lockfile) {
+               fclose(mesh->lockfile);
+               mesh->lockfile = NULL;
        }
 }
 
 /// Read a configuration file from a FILE handle.
-bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config) {
-       (void)mesh;
+bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config, const void *key) {
+       assert(f);
+
        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;
        }
 
@@ -196,17 +551,17 @@ bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config) {
        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) {
+       if(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);
+               chacha_poly1305_set_key(ctx, 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;
@@ -214,6 +569,7 @@ bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config) {
                } else {
                        logger(mesh, MESHLINK_ERROR, "Cannot decrypt config file\n");
                        meshlink_errno = MESHLINK_ESTORAGE;
+                       chacha_poly1305_exit(ctx);
                        free(decrypted);
                        free(buf);
                        return false;
@@ -227,18 +583,26 @@ bool config_read_file(meshlink_handle_t *mesh, FILE *f, config_t *config) {
 }
 
 /// 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) {
+bool config_write_file(meshlink_handle_t *mesh, FILE *f, const config_t *config, const void *key) {
+       assert(f);
+
+       if(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);
+               chacha_poly1305_set_key(ctx, 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;
+
+                       if(!success) {
+                               logger(mesh, MESHLINK_ERROR, "Cannot write config file: %s", strerror(errno));
+                       }
+
+                       meshlink_errno = MESHLINK_ESTORAGE;
                } else {
                        logger(mesh, MESHLINK_ERROR, "Cannot encrypt config file\n");
                        meshlink_errno = MESHLINK_ESTORAGE;
@@ -254,28 +618,54 @@ bool config_write_file(meshlink_handle_t *mesh, FILE *f, const config_t *config)
                return false;
        }
 
+       if(fflush(f)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to flush file: %s", strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       if(fsync(fileno(f))) {
+               logger(mesh, MESHLINK_ERROR, "Failed to sync file: %s\n", strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
        return true;
 }
 
 /// Free resources of a loaded configuration file.
 void config_free(config_t *config) {
+       assert(!config->len || config->buf);
+
        free((uint8_t *)config->buf);
        config->buf = NULL;
        config->len = 0;
 }
 
 /// Check the presence of a host configuration file.
-bool config_exists(meshlink_handle_t *mesh, const char *name) {
+bool config_exists(meshlink_handle_t *mesh, const char *conf_subdir, const char *name) {
+       assert(conf_subdir);
+
+       if(!mesh->confbase) {
+               return false;
+       }
+
        char path[PATH_MAX];
-       make_host_path(mesh, name, path, sizeof(path));
+       make_host_path(mesh, conf_subdir, name, path, sizeof(path));
 
        return access(path, F_OK) == 0;
 }
 
 /// Read a host configuration file.
-bool config_read(meshlink_handle_t *mesh, const char *name, config_t *config) {
+bool config_read(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, config_t *config, void *key) {
+       assert(conf_subdir);
+
+       if(!mesh->confbase) {
+               return false;
+       }
+
        char path[PATH_MAX];
-       make_host_path(mesh, name, path, sizeof(path));
+       make_host_path(mesh, conf_subdir, name, path, sizeof(path));
 
        FILE *f = fopen(path, "r");
 
@@ -284,42 +674,129 @@ bool config_read(meshlink_handle_t *mesh, const char *name, config_t *config) {
                return false;
        }
 
-       if(!config_read_file(mesh, f, config)) {
+       if(!config_read_file(mesh, f, config, key)) {
                logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno));
                fclose(f);
                return false;
        }
 
        fclose(f);
+
+       return true;
+}
+
+bool config_scan_all(meshlink_handle_t *mesh, const char *conf_subdir, const char *conf_type, config_scan_action_t action, void *arg) {
+       assert(conf_subdir);
+       assert(conf_type);
+
+       if(!mesh->confbase) {
+               return true;
+       }
+
+       DIR *dir;
+       struct dirent *ent;
+       char dname[PATH_MAX];
+       snprintf(dname, sizeof(dname), "%s" SLASH "%s" SLASH "%s", mesh->confbase, conf_subdir, conf_type);
+
+       dir = opendir(dname);
+
+       if(!dir) {
+               logger(mesh, MESHLINK_ERROR, "Could not open %s: %s", dname, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       while((ent = readdir(dir))) {
+               if(ent->d_name[0] == '.') {
+                       continue;
+               }
+
+               if(!action(mesh, ent->d_name, arg)) {
+                       closedir(dir);
+                       return false;
+               }
+       }
+
+       closedir(dir);
        return true;
 }
 
 /// Write a host configuration file.
-bool config_write(meshlink_handle_t *mesh, const char *name, const config_t *config) {
+bool config_write(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, const config_t *config, void *key) {
+       assert(conf_subdir);
+       assert(name);
+       assert(config);
+
+       if(!mesh->confbase) {
+               return true;
+       }
+
        char path[PATH_MAX];
-       make_host_path(mesh, name, path, sizeof(path));
+       char tmp_path[PATH_MAX + 4];
+       make_host_path(mesh, conf_subdir, name, path, sizeof(path));
+       snprintf(tmp_path, sizeof(tmp_path), "%s.tmp", path);
 
-       FILE *f = fopen(path, "w");
+       FILE *f = fopen(tmp_path, "w");
 
        if(!f) {
-               logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno));
+               logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", tmp_path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
                return false;
        }
 
-       if(!config_write_file(mesh, f, config)) {
-               logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno));
+       if(!config_write_file(mesh, f, config, key)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", tmp_path, strerror(errno));
                fclose(f);
                return false;
        }
 
-       fclose(f);
+       if(fclose(f)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to close `%s': %s", tmp_path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       if(rename(tmp_path, path)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to rename `%s' to `%s': %s", tmp_path, path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       return true;
+}
+
+/// Delete a host configuration file.
+bool config_delete(meshlink_handle_t *mesh, const char *conf_subdir, const char *name) {
+       assert(conf_subdir);
+       assert(name);
+
+       if(!mesh->confbase) {
+               return true;
+       }
+
+       char path[PATH_MAX];
+       make_host_path(mesh, conf_subdir, name, path, sizeof(path));
+
+       if(unlink(path) && errno != ENOENT) {
+               logger(mesh, MESHLINK_ERROR, "Failed to unlink `%s': %s", path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
        return true;
 }
 
 /// Read the main configuration file.
-bool main_config_read(meshlink_handle_t *mesh, config_t *config) {
+bool main_config_read(meshlink_handle_t *mesh, const char *conf_subdir, config_t *config, void *key) {
+       assert(conf_subdir);
+       assert(config);
+
+       if(!mesh->confbase) {
+               return false;
+       }
+
        char path[PATH_MAX];
-       make_main_path(mesh, path, sizeof(path));
+       make_main_path(mesh, conf_subdir, path, sizeof(path));
 
        FILE *f = fopen(path, "r");
 
@@ -328,44 +805,75 @@ bool main_config_read(meshlink_handle_t *mesh, config_t *config) {
                return false;
        }
 
-       if(!config_read_file(mesh, f, config)) {
+       if(!config_read_file(mesh, f, config, key)) {
                logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno));
                fclose(f);
                return false;
        }
 
        fclose(f);
+
        return true;
 }
 
 /// Write the main configuration file.
-bool main_config_write(meshlink_handle_t *mesh, const config_t *config) {
+bool main_config_write(meshlink_handle_t *mesh, const char *conf_subdir, const config_t *config, void *key) {
+       assert(conf_subdir);
+       assert(config);
+
+       if(!mesh->confbase) {
+               return true;
+       }
+
        char path[PATH_MAX];
-       make_main_path(mesh, path, sizeof(path));
+       char tmp_path[PATH_MAX + 4];
+       make_main_path(mesh, conf_subdir, path, sizeof(path));
+       snprintf(tmp_path, sizeof(tmp_path), "%s.tmp", path);
 
-       FILE *f = fopen(path, "w");
+       FILE *f = fopen(tmp_path, "w");
 
        if(!f) {
-               logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno));
+               logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", tmp_path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
                return false;
        }
 
-       if(!config_write_file(mesh, f, config)) {
-               logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno));
+       if(!config_write_file(mesh, f, config, key)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", tmp_path, strerror(errno));
                fclose(f);
                return false;
        }
 
-       fclose(f);
+       if(rename(tmp_path, path)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to rename `%s' to `%s': %s", tmp_path, path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               fclose(f);
+               return false;
+       }
+
+       if(fclose(f)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to close `%s': %s", tmp_path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
        return true;
 }
 
-/// Read an invitation file, and immediately delete it.
-bool invitation_read(meshlink_handle_t *mesh, const char *name, config_t *config) {
+/// Read an invitation file from the confbase sub-directory, and immediately delete it.
+bool invitation_read(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, config_t *config, void *key) {
+       assert(conf_subdir);
+       assert(name);
+       assert(config);
+
+       if(!mesh->confbase) {
+               return false;
+       }
+
        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));
+       make_invitation_path(mesh, conf_subdir, name, path, sizeof(path));
+       make_used_invitation_path(mesh, conf_subdir, name, used_path, sizeof(used_path));
 
        // Atomically rename the invitation file
        if(rename(path, used_path)) {
@@ -395,14 +903,14 @@ bool invitation_read(meshlink_handle_t *mesh, const char *name, config_t *config
                return false;
        }
 
-       if(time(NULL) > st.st_mtime + mesh->invitation_timeout) {
+       if(mesh->loop.now.tv_sec >= 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(!config_read_file(mesh, f, config)) {
+       if(!config_read_file(mesh, f, config, key)) {
                logger(mesh, MESHLINK_ERROR, "Failed to read `%s': %s", path, strerror(errno));
                fclose(f);
                unlink(used_path);
@@ -410,36 +918,75 @@ bool invitation_read(meshlink_handle_t *mesh, const char *name, config_t *config
        }
 
        fclose(f);
-       unlink(used_path);
+
+       if(unlink(used_path)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to unlink `%s': %s", path, strerror(errno));
+               return false;
+       }
+
+       snprintf(path, sizeof(path), "%s" SLASH "%s" SLASH "invitations", mesh->confbase, conf_subdir);
+
+       if(!sync_path(path)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to sync `%s': %s", path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
        return true;
 }
 
 /// Write an invitation file.
-bool invitation_write(meshlink_handle_t *mesh, const char *name, const config_t *config) {
+bool invitation_write(meshlink_handle_t *mesh, const char *conf_subdir, const char *name, const config_t *config, void *key) {
+       assert(conf_subdir);
+       assert(name);
+       assert(config);
+
+       if(!mesh->confbase) {
+               return false;
+       }
+
        char path[PATH_MAX];
-       make_invitation_path(mesh, name, path, sizeof(path));
+       make_invitation_path(mesh, conf_subdir, name, path, sizeof(path));
 
        FILE *f = fopen(path, "w");
 
        if(!f) {
                logger(mesh, MESHLINK_ERROR, "Failed to open `%s': %s", path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
                return false;
        }
 
-       if(!config_write_file(mesh, f, config)) {
+       if(!config_write_file(mesh, f, config, key)) {
                logger(mesh, MESHLINK_ERROR, "Failed to write `%s': %s", path, strerror(errno));
                fclose(f);
                return false;
        }
 
-       fclose(f);
+       if(fclose(f)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to close `%s': %s", path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
+       snprintf(path, sizeof(path), "%s" SLASH "%s" SLASH "invitations", mesh->confbase, conf_subdir);
+
+       if(!sync_path(path)) {
+               logger(mesh, MESHLINK_ERROR, "Failed to sync `%s': %s", path, strerror(errno));
+               meshlink_errno = MESHLINK_ESTORAGE;
+               return false;
+       }
+
        return true;
 }
 
 /// Purge old invitation files
 size_t invitation_purge_old(meshlink_handle_t *mesh, time_t deadline) {
+       if(!mesh->confbase) {
+               return true;
+       }
+
        char path[PATH_MAX];
-       make_invitation_path(mesh, "", path, sizeof(path));
+       make_invitation_path(mesh, "current", "", path, sizeof(path));
 
        DIR *dir = opendir(path);