#define FUSE_USE_VERSION 26 #include <sys/fsuid.h> #include <sys/types.h> #include <pthread.h> #include <signal.h> #include <limits.h> #include <string.h> #include <stdarg.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <fuse.h> #include <pwd.h> #include <tcl.h> /* * Default cache directory */ #ifndef APPFS_CACHEDIR #define APPFS_CACHEDIR "/var/cache/appfs" #endif /* Debugging macros */ #ifdef DEBUG #define APPFS_DEBUG(x...) { fprintf(stderr, "[debug] %s:%i:%s: ", __FILE__, __LINE__, __func__); fprintf(stderr, x); fprintf(stderr, "\n"); } #else #define APPFS_DEBUG(x...) /**/ #endif /* * SHA1 Tcl Package initializer, from sha1.o */ int Sha1_Init(Tcl_Interp *interp); /* * Thread Specific Data (TSD) for Tcl Interpreter for the current thread */ static pthread_key_t interpKey; /* * Global variables, needed for all threads but only initialized before any * FUSE threads are created */ const char *appfs_cachedir; time_t appfs_boottime; int appfs_fuse_started = 0; /* * Global variables for AppFS caching */ pthread_mutex_t appfs_path_info_cache_mutex = PTHREAD_MUTEX_INITIALIZER; int appfs_path_info_cache_size = 8209; struct appfs_pathinfo *appfs_path_info_cache = NULL; /* * Global variables for AppFS Tcl Interpreter restarting */ int interp_reset_key = 0; /* * AppFS Path Type: Describes the type of path a given file is */ typedef enum { APPFS_PATHTYPE_INVALID, APPFS_PATHTYPE_DOES_NOT_EXIST, APPFS_PATHTYPE_FILE, APPFS_PATHTYPE_DIRECTORY, APPFS_PATHTYPE_SYMLINK, APPFS_PATHTYPE_SOCKET, APPFS_PATHTYPE_FIFO, } appfs_pathtype_t; /* * AppFS Path Information: * Completely describes a specific path, how it should be returned to * to the kernel */ struct appfs_pathinfo { appfs_pathtype_t type; time_t time; char hostname[256]; int packaged; unsigned long long inode; union { struct { int childcount; } dir; struct { int executable; off_t size; } file; struct { off_t size; char source[256]; } symlink; } typeinfo; /* Attributes used only for caching entries */ char *_cache_path; uid_t _cache_uid; }; /* * Create a new Tcl interpreter and completely initialize it */ static Tcl_Interp *appfs_create_TclInterp(char **error_string) { Tcl_Interp *interp; int tcl_ret; APPFS_DEBUG("Creating new Tcl interpreter for TID = 0x%llx", (unsigned long long) pthread_self()); interp = Tcl_CreateInterp(); if (interp == NULL) { fprintf(stderr, "Unable to create Tcl Interpreter. Aborting.\n"); if (error_string) { *error_string = strdup("Unable to create Tcl interpreter."); } return(NULL); } Tcl_Preserve(interp); tcl_ret = Tcl_Init(interp); if (tcl_ret != TCL_OK) { fprintf(stderr, "Unable to initialize Tcl. Aborting.\n"); fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp)); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } tcl_ret = Tcl_Eval(interp, "package ifneeded sha1 1.0 [list load {} sha1]"); if (tcl_ret != TCL_OK) { fprintf(stderr, "Unable to initialize Tcl SHA1. Aborting.\n"); fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp)); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } tcl_ret = Tcl_Eval(interp, "package ifneeded appfsd 1.0 [list load {} appfsd]"); if (tcl_ret != TCL_OK) { fprintf(stderr, "Unable to initialize Tcl AppFS Package. Aborting.\n"); fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp)); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } /* * Load "pki.tcl" in the same way as appfsd.tcl (see below) */ tcl_ret = Tcl_Eval(interp, "" #include "pki.tcl.h" ""); if (tcl_ret != TCL_OK) { fprintf(stderr, "Unable to initialize Tcl PKI. Aborting.\n"); fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp)); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } /* * Load the "appfsd.tcl" script, which is "compiled" into a C header * so that it does not need to exist on the filesystem and can be * directly evaluated. */ tcl_ret = Tcl_Eval(interp, "" #include "appfsd.tcl.h" ""); if (tcl_ret != TCL_OK) { fprintf(stderr, "Unable to initialize Tcl AppFS script. Aborting.\n"); fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp)); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } /* * Set global variables from C to Tcl */ if (Tcl_SetVar(interp, "::appfs::cachedir", appfs_cachedir, TCL_GLOBAL_ONLY) == NULL) { fprintf(stderr, "Unable to set cache directory. This should never fail.\n"); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } /* * Initialize the "appfsd.tcl" environment, which must be done after * global variables are set. */ tcl_ret = Tcl_Eval(interp, "::appfs::init"); if (tcl_ret != TCL_OK) { fprintf(stderr, "Unable to initialize Tcl AppFS script (::appfs::init). Aborting.\n"); fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp)); if (error_string) { *error_string = strdup(Tcl_GetStringResult(interp)); } Tcl_Release(interp); APPFS_DEBUG("Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } /* * Hide some Tcl commands that we do not care to use and which may * slow down run-time operations. */ Tcl_HideCommand(interp, "auto_load_index", "auto_load_index"); Tcl_HideCommand(interp, "unknown", "unknown"); Tcl_HideCommand(interp, "exit", "exit"); /* * Release the hold we have on the interpreter so that it may be * deleted if needed */ Tcl_Release(interp); /* * Return the completely initialized interpreter */ return(interp); } /* * Return the thread-specific Tcl interpreter, creating it if needed */ static Tcl_Interp *appfs_TclInterp(void) { Tcl_Interp *interp; int pthread_ret; static __thread int thread_interp_reset_key = 0; int global_interp_reset_key; global_interp_reset_key = __sync_fetch_and_add(&interp_reset_key, 0); interp = pthread_getspecific(interpKey); if (interp != NULL && thread_interp_reset_key != global_interp_reset_key) { APPFS_DEBUG("Terminating old interpreter and restarting due to reset request."); Tcl_DeleteInterp(interp); interp = NULL; pthread_ret = pthread_setspecific(interpKey, interp); } thread_interp_reset_key = global_interp_reset_key; if (interp == NULL) { interp = appfs_create_TclInterp(NULL); if (interp == NULL) { return(NULL); } pthread_ret = pthread_setspecific(interpKey, interp); if (pthread_ret != 0) { APPFS_DEBUG("pthread_setspecific() failed. Terminating Tcl interpreter."); Tcl_DeleteInterp(interp); return(NULL); } } return(interp); } /* * Evaluate a Tcl script constructed by concatenating a bunch of C strings * together. */ static int appfs_Tcl_Eval(Tcl_Interp *interp, int objc, const char *cmd, ...) { Tcl_Obj **objv; const char *arg; va_list argp; int retval; int i; if (interp == NULL) { return(TCL_ERROR); } objv = (void *) ckalloc(sizeof(*objv) * objc); objv[0] = Tcl_NewStringObj(cmd, -1); Tcl_IncrRefCount(objv[0]); va_start(argp, cmd); for (i = 1; i < objc; i++) { arg = va_arg(argp, const char *); objv[i] = Tcl_NewStringObj(arg, -1); Tcl_IncrRefCount(objv[i]); } va_end(argp); retval = Tcl_EvalObjv(interp, objc, objv, 0); for (i = 0; i < objc; i++) { Tcl_DecrRefCount(objv[i]); } ckfree((void *) objv); if (retval != TCL_OK) { APPFS_DEBUG("Tcl command failed, ::errorInfo contains: %s\n", Tcl_GetVar(interp, "::errorInfo", 0)); } return(retval); } /* * Request all Tcl interpreters restart */ static void appfs_tcl_ResetInterps(void) { APPFS_DEBUG("Requesting reset of all interpreters."); __sync_add_and_fetch(&interp_reset_key, 1); return; } /* * Determine the UID for the user making the current FUSE filesystem request. * This will be used to lookup the user's home directory so we can search for * locally modified files. */ static uid_t appfs_get_fsuid(void) { struct fuse_context *ctx; if (!appfs_fuse_started) { return(getuid()); } ctx = fuse_get_context(); if (ctx == NULL) { /* Unable to lookup user for some reason */ /* Return an unprivileged user ID */ return(1); } return(ctx->uid); } /* * Determine the GID for the user making the current FUSE filesystem request. * This will be used to lookup the user's home directory so we can search for * locally modified files. */ static gid_t appfs_get_fsgid(void) { struct fuse_context *ctx; if (!appfs_fuse_started) { return(getgid()); } ctx = fuse_get_context(); if (ctx == NULL) { /* Unable to lookup user for some reason */ /* Return an unprivileged user ID */ return(1); } return(ctx->gid); } static void appfs_simulate_user_fs_enter(void) { setfsuid(appfs_get_fsuid()); setfsgid(appfs_get_fsgid()); } static void appfs_simulate_user_fs_leave(void) { setfsuid(0); setfsgid(0); } /* * Look up the home directory for a given UID * Returns a C string containing the user's home directory or NULL if * the user's home directory does not exist or is not correctly * configured */ static char *appfs_get_homedir(uid_t fsuid) { struct passwd entry, *result; struct stat stbuf; char buf[1024], *retval; int gpu_ret, stat_ret; gpu_ret = getpwuid_r(fsuid, &entry, buf, sizeof(buf), &result); if (gpu_ret != 0) { APPFS_DEBUG("getpwuid_r(%llu, ...) returned in failure", (unsigned long long) fsuid); return(NULL); } if (result == NULL) { APPFS_DEBUG("getpwuid_r(%llu, ...) returned NULL result", (unsigned long long) fsuid); return(NULL); } if (result->pw_dir == NULL) { APPFS_DEBUG("getpwuid_r(%llu, ...) returned NULL home directory", (unsigned long long) fsuid); return(NULL); } stat_ret = stat(result->pw_dir, &stbuf); if (stat_ret != 0) { APPFS_DEBUG("stat(%s) returned in failure", result->pw_dir); return(NULL); } if (stbuf.st_uid != fsuid) { APPFS_DEBUG("UID mis-match on user %llu's home directory (%s). It's owned by %llu.", (unsigned long long) fsuid, result->pw_dir, (unsigned long long) stbuf.st_uid ); return(NULL); } retval = strdup(result->pw_dir); return(retval); } /* * Generate an inode for a given path. The inode should be computed in such * a way that it is unlikely to be duplicated and remains the same for a given * file */ #if UINT_MAX < 4294967295 #error Integer size is too small #endif static unsigned long long appfs_get_path_inode(const char *path) { int retval; const char *p; retval = 10; for (p = path; *p; p++) { retval += *p; retval <<= 6; } retval += 10; retval %= 4294967286ULL; retval += 10; return(retval); } /* * Cache Get Path Info lookups for speed */ static int appfs_get_path_info_cache_get(const char *path, uid_t uid, struct appfs_pathinfo *pathinfo) { unsigned int hash_idx; int pthread_ret; int retval; retval = 1; pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to lock path_info cache mutex !"); return(-1); } if (appfs_path_info_cache != NULL) { hash_idx = (appfs_get_path_inode(path) + uid) % appfs_path_info_cache_size; if (appfs_path_info_cache[hash_idx]._cache_path != NULL) { if (strcmp(appfs_path_info_cache[hash_idx]._cache_path, path) == 0 && appfs_path_info_cache[hash_idx]._cache_uid == uid) { retval = 0; memcpy(pathinfo, &appfs_path_info_cache[hash_idx], sizeof(*pathinfo)); pathinfo->_cache_path = NULL; } } } pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to unlock path_info cache mutex !"); return(-1); } if (retval == 0) { APPFS_DEBUG("Cache hit on %s", path); } else { APPFS_DEBUG("Cache miss on %s", path); } return(retval); } static void appfs_get_path_info_cache_add(const char *path, uid_t uid, struct appfs_pathinfo *pathinfo) { unsigned int hash_idx; int pthread_ret; pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to lock path_info cache mutex !"); return; } if (appfs_path_info_cache == NULL) { appfs_path_info_cache = calloc(appfs_path_info_cache_size, sizeof(*appfs_path_info_cache)); } hash_idx = (appfs_get_path_inode(path) + uid) % appfs_path_info_cache_size; if (appfs_path_info_cache[hash_idx]._cache_path != NULL) { free(appfs_path_info_cache[hash_idx]._cache_path); } memcpy(&appfs_path_info_cache[hash_idx], pathinfo, sizeof(*pathinfo)); appfs_path_info_cache[hash_idx]._cache_path = strdup(path); appfs_path_info_cache[hash_idx]._cache_uid = uid; pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to unlock path_info cache mutex !"); return; } return; } static void appfs_get_path_info_cache_rm(const char *path, uid_t uid) { unsigned int hash_idx; int pthread_ret; pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to lock path_info cache mutex !"); return; } if (appfs_path_info_cache != NULL) { hash_idx = (appfs_get_path_inode(path) + uid) % appfs_path_info_cache_size; if (appfs_path_info_cache[hash_idx]._cache_path != NULL) { free(appfs_path_info_cache[hash_idx]._cache_path); appfs_path_info_cache[hash_idx]._cache_path = NULL; } } pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to unlock path_info cache mutex !"); return; } return; } static void appfs_get_path_info_cache_flush(uid_t uid, int new_size) { unsigned int idx; int pthread_ret; APPFS_DEBUG("Flushing AppFS cache (uid = %lli, new_size = %i)", (long long) uid, new_size); pthread_ret = pthread_mutex_lock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to lock path_info cache mutex !"); return; } if (appfs_path_info_cache != NULL) { for (idx = 0; idx < appfs_path_info_cache_size; idx++) { if (appfs_path_info_cache[idx]._cache_path != NULL) { if (uid != ((uid_t) -1)) { if (appfs_path_info_cache[idx]._cache_uid != uid) { continue; } } free(appfs_path_info_cache[idx]._cache_path); appfs_path_info_cache[idx]._cache_path = NULL; } } } if (uid == ((uid_t) -1)) { free(appfs_path_info_cache); appfs_path_info_cache = NULL; if (new_size != -1) { appfs_path_info_cache_size = new_size; } } pthread_ret = pthread_mutex_unlock(&appfs_path_info_cache_mutex); if (pthread_ret != 0) { APPFS_DEBUG("Unable to unlock path_info cache mutex !"); return; } return; } /* Get information about a path, and optionally list children */ static int appfs_get_path_info(const char *path, struct appfs_pathinfo *pathinfo) { Tcl_Interp *interp; Tcl_Obj *attrs_dict, *attr_value; const char *attr_value_str; Tcl_WideInt attr_value_wide; int attr_value_int; static __thread Tcl_Obj *attr_key_type = NULL, *attr_key_perms = NULL, *attr_key_size = NULL, *attr_key_time = NULL, *attr_key_source = NULL, *attr_key_childcount = NULL, *attr_key_packaged = NULL; int cache_ret; int tcl_ret; uid_t fsuid; fsuid = appfs_get_fsuid(); cache_ret = appfs_get_path_info_cache_get(path, fsuid, pathinfo); if (cache_ret == 0) { if (pathinfo->type == APPFS_PATHTYPE_DOES_NOT_EXIST) { return(-ENOENT); } if (pathinfo->type == APPFS_PATHTYPE_INVALID) { return(-EIO); } return(0); } interp = appfs_TclInterp(); if (interp == NULL) { return(-EIO); } Tcl_Preserve(interp); tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::getattr", path); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::getattr(%s) failed.", path); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); pathinfo->type = APPFS_PATHTYPE_DOES_NOT_EXIST; appfs_get_path_info_cache_add(path, fsuid, pathinfo); Tcl_Release(interp); return(-ENOENT); } if (attr_key_type == NULL) { attr_key_type = Tcl_NewStringObj("type", -1); attr_key_perms = Tcl_NewStringObj("perms", -1); attr_key_size = Tcl_NewStringObj("size", -1); attr_key_time = Tcl_NewStringObj("time", -1); attr_key_source = Tcl_NewStringObj("source", -1); attr_key_childcount = Tcl_NewStringObj("childcount", -1); attr_key_packaged = Tcl_NewStringObj("packaged", -1); } attrs_dict = Tcl_GetObjResult(interp); tcl_ret = Tcl_DictObjGet(interp, attrs_dict, attr_key_type, &attr_value); if (tcl_ret != TCL_OK) { APPFS_DEBUG("[dict get \"type\"] failed"); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(-EIO); } if (attr_value == NULL) { Tcl_Release(interp); return(-EIO); } pathinfo->packaged = 0; pathinfo->inode = appfs_get_path_inode(path); attr_value_str = Tcl_GetString(attr_value); switch (attr_value_str[0]) { case 'd': /* directory */ pathinfo->type = APPFS_PATHTYPE_DIRECTORY; pathinfo->typeinfo.dir.childcount = 0; Tcl_DictObjGet(interp, attrs_dict, attr_key_childcount, &attr_value); if (attr_value != NULL) { tcl_ret = Tcl_GetWideIntFromObj(NULL, attr_value, &attr_value_wide); if (tcl_ret == TCL_OK) { pathinfo->typeinfo.dir.childcount = attr_value_wide; } } break; case 'f': /* file */ pathinfo->type = APPFS_PATHTYPE_FILE; pathinfo->typeinfo.file.size = 0; pathinfo->typeinfo.file.executable = 0; Tcl_DictObjGet(interp, attrs_dict, attr_key_size, &attr_value); if (attr_value != NULL) { tcl_ret = Tcl_GetWideIntFromObj(NULL, attr_value, &attr_value_wide); if (tcl_ret == TCL_OK) { pathinfo->typeinfo.file.size = attr_value_wide; } } Tcl_DictObjGet(interp, attrs_dict, attr_key_perms, &attr_value); if (attr_value != NULL) { attr_value_str = Tcl_GetString(attr_value); if (attr_value_str[0] == 'x') { pathinfo->typeinfo.file.executable = 1; } } break; case 's': /* symlink */ pathinfo->type = APPFS_PATHTYPE_SYMLINK; pathinfo->typeinfo.symlink.size = 0; pathinfo->typeinfo.symlink.source[0] = '\0'; Tcl_DictObjGet(interp, attrs_dict, attr_key_source, &attr_value); if (attr_value != NULL) { attr_value_str = Tcl_GetStringFromObj(attr_value, &attr_value_int); if ((attr_value_int + 1) <= sizeof(pathinfo->typeinfo.symlink.source)) { pathinfo->typeinfo.symlink.size = attr_value_int; pathinfo->typeinfo.symlink.source[attr_value_int] = '\0'; memcpy(pathinfo->typeinfo.symlink.source, attr_value_str, attr_value_int); } } break; case 'F': /* pipe/fifo */ pathinfo->type = APPFS_PATHTYPE_FIFO; break; case 'S': /* UNIX domain socket */ pathinfo->type = APPFS_PATHTYPE_SOCKET; break; default: Tcl_Release(interp); return(-EIO); } Tcl_DictObjGet(interp, attrs_dict, attr_key_packaged, &attr_value); if (attr_value != NULL) { pathinfo->packaged = 1; } Tcl_DictObjGet(interp, attrs_dict, attr_key_time, &attr_value); if (attr_value != NULL) { tcl_ret = Tcl_GetWideIntFromObj(NULL, attr_value, &attr_value_wide); if (tcl_ret == TCL_OK) { pathinfo->time = attr_value_wide; } } else { pathinfo->time = 0; } Tcl_Release(interp); appfs_get_path_info_cache_add(path, fsuid, pathinfo); return(0); } static char *appfs_prepare_to_create(const char *path) { Tcl_Interp *interp; const char *real_path; int tcl_ret; appfs_get_path_info_cache_flush(appfs_get_fsuid(), -1); interp = appfs_TclInterp(); if (interp == NULL) { return(NULL); } Tcl_Preserve(interp); tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::prepare_to_create", path); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::prepare_to_create(%s) failed.", path); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(NULL); } real_path = Tcl_GetStringResult(interp); Tcl_Release(interp); if (real_path == NULL) { return(NULL); } return(strdup(real_path)); } static char *appfs_localpath(const char *path) { Tcl_Interp *interp; const char *real_path; int tcl_ret; interp = appfs_TclInterp(); if (interp == NULL) { return(NULL); } Tcl_Preserve(interp); tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::localpath", path); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::localpath(%s) failed.", path); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); return(NULL); } real_path = Tcl_GetStringResult(interp); Tcl_Release(interp); if (real_path == NULL) { return(NULL); } return(strdup(real_path)); } static int appfs_fuse_readlink(const char *path, char *buf, size_t size) { struct appfs_pathinfo pathinfo; int retval = 0; APPFS_DEBUG("Enter (path = %s, ...)", path); pathinfo.type = APPFS_PATHTYPE_INVALID; retval = appfs_get_path_info(path, &pathinfo); if (retval != 0) { return(retval); } if (pathinfo.type != APPFS_PATHTYPE_SYMLINK) { return(-EINVAL); } if ((strlen(pathinfo.typeinfo.symlink.source) + 1) > size) { return(-ENAMETOOLONG); } memcpy(buf, pathinfo.typeinfo.symlink.source, strlen(pathinfo.typeinfo.symlink.source) + 1); return(0); } static int appfs_fuse_getattr(const char *path, struct stat *stbuf) { struct appfs_pathinfo pathinfo; int retval; retval = 0; APPFS_DEBUG("Enter (path = %s, ...)", path); pathinfo.type = APPFS_PATHTYPE_INVALID; retval = appfs_get_path_info(path, &pathinfo); if (retval != 0) { return(retval); } memset(stbuf, 0, sizeof(struct stat)); stbuf->st_mtime = pathinfo.time; stbuf->st_ctime = pathinfo.time; stbuf->st_atime = pathinfo.time; stbuf->st_ino = pathinfo.inode; stbuf->st_mode = 0; switch (pathinfo.type) { case APPFS_PATHTYPE_DIRECTORY: stbuf->st_mode = S_IFDIR | 0555; stbuf->st_nlink = 2 + pathinfo.typeinfo.dir.childcount; break; case APPFS_PATHTYPE_FILE: if (pathinfo.typeinfo.file.executable) { stbuf->st_mode = S_IFREG | 0555; } else { stbuf->st_mode = S_IFREG | 0444; } stbuf->st_nlink = 1; stbuf->st_size = pathinfo.typeinfo.file.size; break; case APPFS_PATHTYPE_SYMLINK: stbuf->st_mode = S_IFLNK | 0555; stbuf->st_nlink = 1; stbuf->st_size = pathinfo.typeinfo.symlink.size; break; case APPFS_PATHTYPE_SOCKET: stbuf->st_mode = S_IFSOCK | 0555; stbuf->st_nlink = 1; stbuf->st_size = 0; break; case APPFS_PATHTYPE_FIFO: stbuf->st_mode = S_IFIFO | 0555; stbuf->st_nlink = 1; stbuf->st_size = 0; break; case APPFS_PATHTYPE_DOES_NOT_EXIST: retval = -ENOENT; break; case APPFS_PATHTYPE_INVALID: retval = -EIO; break; } if (pathinfo.packaged) { stbuf->st_uid = appfs_get_fsuid(); stbuf->st_gid = appfs_get_fsgid(); stbuf->st_mode |= 0200; } return(retval); } static int appfs_fuse_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, struct fuse_file_info *fi) { Tcl_Interp *interp; Tcl_Obj **children; int children_count, idx; int tcl_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); interp = appfs_TclInterp(); if (interp == NULL) { return(0); } Tcl_Preserve(interp); filler(buf, ".", NULL, 0); filler(buf, "..", NULL, 0); tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::getchildren", path); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::getchildren(%s) failed.", path); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(0); } tcl_ret = Tcl_ListObjGetElements(interp, Tcl_GetObjResult(interp), &children_count, &children); if (tcl_ret != TCL_OK) { APPFS_DEBUG("Parsing list of children on path %s failed.", path); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(0); } for (idx = 0; idx < children_count; idx++) { filler(buf, Tcl_GetString(children[idx]), NULL, 0); } Tcl_Release(interp); return(0); } static int appfs_fuse_open(const char *path, struct fuse_file_info *fi) { Tcl_Interp *interp; struct appfs_pathinfo pathinfo; const char *real_path, *mode; int gpi_ret, tcl_ret; int fh; APPFS_DEBUG("Enter (path = %s, ...)", path); gpi_ret = appfs_get_path_info(path, &pathinfo); if ((fi->flags & (O_WRONLY|O_CREAT)) == (O_CREAT|O_WRONLY)) { /* The file will be created if it does not exist */ if (gpi_ret != 0 && gpi_ret != -ENOENT) { return(gpi_ret); } mode = "create"; /* * We have to clear the cache here so that the number of * links gets maintained on the parent directory */ appfs_get_path_info_cache_flush(appfs_get_fsuid(), -1); } else { /* The file must already exist */ if (gpi_ret != 0) { return(gpi_ret); } mode = ""; if ((fi->flags & O_WRONLY) == O_WRONLY) { mode = "write"; } } if (pathinfo.type == APPFS_PATHTYPE_DIRECTORY) { return(-EISDIR); } interp = appfs_TclInterp(); if (interp == NULL) { return(-EIO); } Tcl_Preserve(interp); tcl_ret = appfs_Tcl_Eval(interp, 3, "::appfs::openpath", path, mode); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::openpath(%s, %s) failed.", path, mode); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(-EIO); } real_path = Tcl_GetStringResult(interp); Tcl_Release(interp); if (real_path == NULL) { return(-EIO); } APPFS_DEBUG("Translated request to open %s to opening %s (mode = \"%s\")", path, real_path, mode); fh = open(real_path, fi->flags, 0600); if (fh < 0) { return(-EIO); } fi->fh = fh; return(0); } static int appfs_fuse_close(const char *path, struct fuse_file_info *fi) { int close_ret; appfs_get_path_info_cache_rm(path, appfs_get_fsuid()); close_ret = close(fi->fh); if (close_ret != 0) { return(-EIO); } return(0); } static int appfs_fuse_read(const char *path, char *buf, size_t size, off_t offset, struct fuse_file_info *fi) { off_t lseek_ret; ssize_t read_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); lseek_ret = lseek(fi->fh, offset, SEEK_SET); if (lseek_ret != offset) { return(-EIO); } read_ret = read(fi->fh, buf, size); return(read_ret); } static int appfs_fuse_write(const char *path, const char *buf, size_t size, off_t offset, struct fuse_file_info *fi) { off_t lseek_ret; ssize_t write_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); appfs_get_path_info_cache_rm(path, appfs_get_fsuid()); lseek_ret = lseek(fi->fh, offset, SEEK_SET); if (lseek_ret != offset) { return(-EIO); } write_ret = write(fi->fh, buf, size); return(write_ret); } static int appfs_fuse_mknod(const char *path, mode_t mode, dev_t device) { char *real_path; int mknod_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); if ((mode & S_IFCHR) == S_IFCHR) { return(-EPERM); } if ((mode & S_IFBLK) == S_IFBLK) { return(-EPERM); } real_path = appfs_prepare_to_create(path); if (real_path == NULL) { return(-EIO); } appfs_simulate_user_fs_enter(); mknod_ret = mknod(real_path, mode, device); appfs_simulate_user_fs_leave(); free(real_path); if (mknod_ret != 0) { return(errno * -1); } return(0); } static int appfs_fuse_create(const char *path, mode_t mode, struct fuse_file_info *fi) { char *real_path; int fd; APPFS_DEBUG("Enter (path = %s, ...)", path); if ((mode & S_IFCHR) == S_IFCHR) { return(-EPERM); } if ((mode & S_IFBLK) == S_IFBLK) { return(-EPERM); } real_path = appfs_prepare_to_create(path); if (real_path == NULL) { return(-EIO); } appfs_simulate_user_fs_enter(); fd = creat(real_path, mode); appfs_simulate_user_fs_leave(); free(real_path); if (fd < 0) { return(errno * -1); } fi->fh = fd; return(0); } static int appfs_fuse_truncate(const char *path, off_t size) { char *real_path; int truncate_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); real_path = appfs_localpath(path); if (real_path == NULL) { return(-EIO); } appfs_get_path_info_cache_rm(path, appfs_get_fsuid()); appfs_simulate_user_fs_enter(); truncate_ret = truncate(real_path, size); appfs_simulate_user_fs_leave(); free(real_path); if (truncate_ret != 0) { return(errno * -1); } return(0); } static int appfs_fuse_unlink_rmdir(const char *path) { Tcl_Interp *interp; int tcl_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); appfs_get_path_info_cache_flush(appfs_get_fsuid(), -1); interp = appfs_TclInterp(); if (interp == NULL) { return(-EIO); } tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::unlinkpath", path); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::unlinkpath(%s) failed.", path); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(-EIO); } Tcl_Release(interp); return(0); } static int appfs_fuse_mkdir(const char *path, mode_t mode) { char *real_path; int mkdir_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); real_path = appfs_prepare_to_create(path); if (real_path == NULL) { return(-EIO); } appfs_simulate_user_fs_enter(); mkdir_ret = mkdir(real_path, mode); appfs_simulate_user_fs_leave(); free(real_path); if (mkdir_ret != 0) { if (errno != EEXIST) { return(errno * -1); } } return(0); } static int appfs_fuse_chmod(const char *path, mode_t mode) { Tcl_Interp *interp; const char *real_path; int tcl_ret, chmod_ret; APPFS_DEBUG("Enter (path = %s, ...)", path); appfs_get_path_info_cache_rm(path, appfs_get_fsuid()); interp = appfs_TclInterp(); if (interp == NULL) { return(-EIO); } Tcl_Preserve(interp); tcl_ret = appfs_Tcl_Eval(interp, 3, "::appfs::openpath", path, "write"); if (tcl_ret != TCL_OK) { APPFS_DEBUG("::appfs::openpath(%s, %s) failed.", path, "write"); APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp)); Tcl_Release(interp); return(-EIO); } real_path = Tcl_GetStringResult(interp); Tcl_Release(interp); if (real_path == NULL) { return(-EIO); } appfs_simulate_user_fs_enter(); chmod_ret = chmod(real_path, mode); appfs_simulate_user_fs_leave(); return(chmod_ret); } /* * SQLite3 mode: Execute raw SQL and return success or failure */ static int appfs_sqlite3(const char *sql) { Tcl_Interp *interp; const char *sql_ret; int tcl_ret; interp = appfs_create_TclInterp(NULL); if (interp == NULL) { fprintf(stderr, "Unable to create a Tcl interpreter. Aborting.\n"); return(1); } tcl_ret = appfs_Tcl_Eval(interp, 5, "::appfs::db", "eval", sql, "row", "unset -nocomplain row(*); parray row; puts \"----\""); sql_ret = Tcl_GetStringResult(interp); if (tcl_ret != TCL_OK) { fprintf(stderr, "[error] %s\n", sql_ret); return(1); } if (sql_ret && sql_ret[0] != '\0') { printf("%s\n", sql_ret); } return(0); } /* * Tcl mode: Execute raw Tcl and return success or failure */ static int appfs_tcl(const char *tcl) { Tcl_Interp *interp; const char *tcl_result; int tcl_ret; interp = appfs_create_TclInterp(NULL); if (interp == NULL) { fprintf(stderr, "Unable to create a Tcl interpreter. Aborting.\n"); return(1); } tcl_ret = Tcl_Eval(interp, tcl); tcl_result = Tcl_GetStringResult(interp); if (tcl_ret != TCL_OK) { fprintf(stderr, "[error] %s\n", tcl_result); return(1); } if (tcl_result && tcl_result[0] != '\0') { printf("%s\n", tcl_result); } return(0); } /* * AppFSd Package for Tcl: * Bridge for I/O operations to request information about the current * transaction */ /* * Tcl interface to get the home directory for the user making the "current" * FUSE I/O request */ static int tcl_appfs_get_homedir(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) { char *homedir; Tcl_Obj *homedir_obj; uid_t fsuid; static __thread Tcl_Obj *last_homedir_obj = NULL; static __thread uid_t last_fsuid = -1; if (objc != 1) { Tcl_WrongNumArgs(interp, 1, objv, NULL); return(TCL_ERROR); } fsuid = appfs_get_fsuid(); if (fsuid == last_fsuid && last_homedir_obj != NULL) { homedir_obj = last_homedir_obj; } else { homedir = appfs_get_homedir(appfs_get_fsuid()); if (homedir == NULL) { return(TCL_ERROR); } homedir_obj = Tcl_NewStringObj(homedir, -1); free(homedir); if (last_homedir_obj != NULL) { Tcl_DecrRefCount(last_homedir_obj); } last_homedir_obj = homedir_obj; last_fsuid = fsuid; Tcl_IncrRefCount(last_homedir_obj); } Tcl_SetObjResult(interp, homedir_obj); return(TCL_OK); } static int tcl_appfs_simulate_user_fs_enter(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) { appfs_simulate_user_fs_enter(); return(TCL_OK); } static int tcl_appfs_simulate_user_fs_leave(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) { appfs_simulate_user_fs_leave(); return(TCL_OK); } static int tcl_appfs_get_fsuid(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) { uid_t fsuid; fsuid = appfs_get_fsuid(); Tcl_SetObjResult(interp, Tcl_NewWideIntObj(fsuid)); return(TCL_OK); } static int tcl_appfs_get_fsgid(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) { gid_t fsgid; fsgid = appfs_get_fsgid(); Tcl_SetObjResult(interp, Tcl_NewWideIntObj(fsgid)); return(TCL_OK); } static int tcl_appfs_get_path_info_cache_flush(ClientData cd, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) { int tcl_ret; int new_size; new_size = -1; if (objc == 2) { tcl_ret = Tcl_GetIntFromObj(interp, objv[1], &new_size); if (tcl_ret != TCL_OK) { return(tcl_ret); } } else if (objc > 2 || objc < 1) { Tcl_WrongNumArgs(interp, 1, objv, "?new_cache_size?"); return(TCL_ERROR); } appfs_get_path_info_cache_flush(-1, new_size); return(TCL_OK); } static int Appfsd_Init(Tcl_Interp *interp) { #ifdef USE_TCL_STUBS if (Tcl_InitStubs(interp, TCL_VERSION, 0) == 0L) { return(TCL_ERROR); } #endif Tcl_CreateObjCommand(interp, "appfsd::get_homedir", tcl_appfs_get_homedir, NULL, NULL); Tcl_CreateObjCommand(interp, "appfsd::get_fsuid", tcl_appfs_get_fsuid, NULL, NULL); Tcl_CreateObjCommand(interp, "appfsd::get_fsgid", tcl_appfs_get_fsgid, NULL, NULL); Tcl_CreateObjCommand(interp, "appfsd::simulate_user_fs_enter", tcl_appfs_simulate_user_fs_enter, NULL, NULL); Tcl_CreateObjCommand(interp, "appfsd::simulate_user_fs_leave", tcl_appfs_simulate_user_fs_leave, NULL, NULL); Tcl_CreateObjCommand(interp, "appfsd::get_path_info_cache_flush", tcl_appfs_get_path_info_cache_flush, NULL, NULL); Tcl_PkgProvide(interp, "appfsd", "1.0"); return(TCL_OK); } /* * Hot-restart support */ /* Initiate a hot-restart */ static void appfs_hot_restart(void) { APPFS_DEBUG("Asked to initiate hot restart"); appfs_tcl_ResetInterps(); appfs_get_path_info_cache_flush(-1, -1); return; } /* * Signal handler * SIGHUP initiates a hot restart */ static void appfs_signal_handler(int sig) { /* Do not handle signals until FUSE has been started */ if (!appfs_fuse_started) { return; } /* Request to perform a "hot" restart */ if (sig == SIGHUP) { appfs_hot_restart(); } return; } /* * Terminate a thread */ static void appfs_terminate_interp(void *_interp) { Tcl_Interp *interp; APPFS_DEBUG("Called: _interp = %p", _interp); if (_interp == NULL) { APPFS_DEBUG("Terminating thread with no interpreter"); return; } interp = _interp; APPFS_DEBUG("Terminating interpreter due to thread termination"); Tcl_DeleteInterp(interp); return; } /* * FUSE operations structure */ static struct fuse_operations appfs_operations = { .getattr = appfs_fuse_getattr, .readdir = appfs_fuse_readdir, .readlink = appfs_fuse_readlink, .open = appfs_fuse_open, .release = appfs_fuse_close, .read = appfs_fuse_read, .write = appfs_fuse_write, .mknod = appfs_fuse_mknod, .create = appfs_fuse_create, .truncate = appfs_fuse_truncate, .unlink = appfs_fuse_unlink_rmdir, .rmdir = appfs_fuse_unlink_rmdir, .mkdir = appfs_fuse_mkdir, .chmod = appfs_fuse_chmod, }; /* * FUSE option parsing callback */ static int appfs_fuse_opt_cb(void *data, const char *arg, int key, struct fuse_args *outargs) { static int seen_cachedir = 0; if (key == FUSE_OPT_KEY_NONOPT && seen_cachedir == 0) { seen_cachedir = 1; appfs_cachedir = strdup(arg); return(0); } return(1); } /* * Entry point into this program. */ int main(int argc, char **argv) { Tcl_Interp *test_interp; char *test_interp_error; struct fuse_args args = FUSE_ARGS_INIT(argc, argv); int pthread_ret; void *signal_ret; /* * Skip passed program name */ if (argc == 0 || argv == NULL) { return(1); } argc--; argv++; /* * Set global variables, these should be configuration options. */ appfs_cachedir = APPFS_CACHEDIR; /* * Set global variable for "boot time" to set a time on directories * that we fake. */ appfs_boottime = time(NULL); /* * Register "sha1" and "appfsd" package with libtcl so that any new * interpreters created (which are done dynamically by FUSE) can have * the appropriate configuration done automatically. */ Tcl_StaticPackage(NULL, "sha1", Sha1_Init, NULL); Tcl_StaticPackage(NULL, "appfsd", Appfsd_Init, NULL); /* * Create a thread-specific-data (TSD) key for each thread to refer * to its own Tcl interpreter. Tcl interpreters must be unique per * thread and new threads are dynamically created by FUSE. */ pthread_ret = pthread_key_create(&interpKey, appfs_terminate_interp); if (pthread_ret != 0) { fprintf(stderr, "Unable to create TSD key for Tcl. Aborting.\n"); return(1); } /* * Manually specify cache directory, without FUSE callback * This option only works when not using FUSE, since we * do not process it with FUSEs option processing. */ if (argc >= 2) { if (strcmp(argv[0], "--cachedir") == 0) { appfs_cachedir = strdup(argv[1]); argc -= 2; argv += 2; } } /* * SQLite3 mode, for running raw SQL against the cache database */ if (argc == 2 && strcmp(argv[0], "--sqlite3") == 0) { return(appfs_sqlite3(argv[1])); } /* * Tcl mode, for running raw Tcl in the same environment AppFSd would * run code. */ if (argc == 2 && strcmp(argv[0], "--tcl") == 0) { return(appfs_tcl(argv[1])); } /* * Create a Tcl interpreter just to verify that things are in working * order before we become a daemon. */ test_interp = appfs_create_TclInterp(&test_interp_error); if (test_interp == NULL) { if (test_interp_error == NULL) { test_interp_error = "Unknown error"; } fprintf(stderr, "Unable to initialize Tcl interpreter for AppFSd:\n"); fprintf(stderr, "%s\n", test_interp_error); return(1); } Tcl_DeleteInterp(test_interp); Tcl_FinalizeNotifier(NULL); /* * Register a signal handler for hot-restart requests */ signal_ret = signal(SIGHUP, appfs_signal_handler); if (signal_ret == SIG_ERR) { fprintf(stderr, "Unable to install signal handler for hot-restart\n"); fprintf(stderr, "Hot-restart will not be available.\n"); } /* * Add FUSE arguments which we always supply */ fuse_opt_parse(&args, NULL, NULL, appfs_fuse_opt_cb); fuse_opt_add_arg(&args, "-odefault_permissions,fsname=appfs,subtype=appfsd,use_ino,kernel_cache,entry_timeout=0,attr_timeout=0,big_writes,intr,hard_remove"); if (getuid() == 0) { fuse_opt_parse(&args, NULL, NULL, NULL); fuse_opt_add_arg(&args, "-oallow_other"); } /* * Enter the FUSE main loop -- this will process any arguments * and start servicing requests. */ appfs_fuse_started = 1; return(fuse_main(args.argc, args.argv, &appfs_operations, NULL)); }