diff options
Diffstat (limited to 'trans/magic.c')
-rw-r--r-- | trans/magic.c | 396 |
1 files changed, 304 insertions, 92 deletions
diff --git a/trans/magic.c b/trans/magic.c index 045033e8..680e88e1 100644 --- a/trans/magic.c +++ b/trans/magic.c @@ -1,7 +1,6 @@ /* A translator for returning FS_RETRY_MAGIC strings. - Copyright (C) 1995, 1997, 1998 Free Software Foundation, Inc. - Written by Miles Bader <miles@gnu.ai.mit.edu> + Copyright (C) 1999 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as @@ -18,138 +17,351 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <hurd.h> -#include <stdio.h> -#include <error.h> -#include <argp.h> +#include <hurd/ports.h> +#include <hurd/trivfs.h> #include <hurd/fsys.h> -#include "fsys_S.h" #include <version.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#include <error.h> +#include <string.h> +#include <dirent.h> +#include <fcntl.h> +#include <limits.h> +#include <argp.h> +#include <argz.h> +#include <assert.h> + const char *argp_program_version = STANDARD_HURD_VERSION (magic); static char args_doc[] = "MAGIC"; static char doc[] = "A translator that returns the magic retry result MAGIC"; - -extern int fsys_server (mach_msg_header_t *, mach_msg_header_t *); +static const struct argp_option options[] = +{ + {"directory", 'd', 0, 0, "Provide virtual (empty) directory node"}, + {0} +}; /* The magic string we return for lookups. */ -static char *magic = NULL; +static char *magic; -int -main (int argc, char **argv) -{ - error_t err; - size_t arg_index; - mach_port_t bootstrap, control, realnode; - struct argp argp = { 0, 0, args_doc, doc }; +static int directory; /* --directory flag */ - argp_parse (&argp, argc, argv, 0, &arg_index, 0); - magic = argv[arg_index]; +/* Pre-fab contents of dummy directory for dir_readdir. + Set up only under --directory. */ +static void *dirbuf; +static size_t dirbufsize; + +/* Trivfs hooks */ - task_get_bootstrap_port (mach_task_self (), &bootstrap); - if (bootstrap == MACH_PORT_NULL) - error (3, 0, "Must be started as a translator"); +int trivfs_fstype = FSTYPE_DEV; +int trivfs_fsid = 0; - /* Reply to our parent */ - mach_port_allocate (mach_task_self (), MACH_PORT_RIGHT_RECEIVE, &control); - err = - fsys_startup (bootstrap, 0, control, MACH_MSG_TYPE_MAKE_SEND, &realnode); - mach_port_deallocate (mach_task_self (), bootstrap); - if (err) - error (1, err, "starting translator"); +int trivfs_support_read = 0; +int trivfs_support_write = 0; +int trivfs_support_exec = 0; - /* Launch */ - while (1) - { - /* The timeout here is 10 minutes */ - err = mach_msg_server_timeout (fsys_server, 0, control, - MACH_RCV_TIMEOUT, 1000 * 60 * 10); - if (err == MACH_RCV_TIMED_OUT) - return 0; - } -} - -error_t -S_fsys_getroot (mach_port_t fsys_t, - mach_port_t dotdotnode, - uid_t *uids, u_int nuids, uid_t *gids, u_int ngids, - int flags, - retry_type *do_retry, char *retry_name, - mach_port_t *ret, mach_msg_type_name_t *rettype) -{ - strcpy(retry_name, magic); - *do_retry = FS_RETRY_MAGICAL; - *ret = MACH_PORT_NULL; - *rettype = MACH_MSG_TYPE_COPY_SEND; - return 0; -} +int trivfs_allow_open = O_READ; -error_t -S_fsys_startup (mach_port_t bootstrap, - int flags, mach_port_t control, - mach_port_t *real, mach_msg_type_name_t *real_type) +void +trivfs_modify_stat (struct trivfs_protid *cred, struct stat *st) { - return EOPNOTSUPP; + st->st_size = dirbufsize; + st->st_blocks = getpagesize () / S_BLKSIZE; + + st->st_mode = ((st->st_mode & ~S_IFMT & ~ALLPERMS) + | S_IFDIR | S_IXUSR|S_IXGRP|S_IXOTH + | (st->st_mode & (S_IRUSR|S_IRGRP|S_IROTH))); } error_t -S_fsys_goaway (mach_port_t control, - int flags) +trivfs_goaway (struct trivfs_control *fsys, int flags) { exit (0); } -error_t -S_fsys_syncfs (mach_port_t control, - int wait, - int recurse) + +/* This hook is used when running without --directory; + it circumvents basically all the trivfs machinery. */ + +static error_t +magic_getroot (struct trivfs_control *cntl, + mach_port_t reply_port, + mach_msg_type_name_t reply_port_type, + mach_port_t dotdot, + uid_t *uids, u_int nuids, uid_t *gids, u_int ngids, + int flags, + retry_type *do_retry, char *retry_name, + mach_port_t *node, mach_msg_type_name_t *node_type) { + strcpy (retry_name, magic); + *do_retry = FS_RETRY_MAGICAL; + *node = MACH_PORT_NULL; + *node_type = MACH_MSG_TYPE_COPY_SEND; return 0; } -error_t -S_fsys_set_options (mach_port_t control, - char *data, mach_msg_type_number_t len, - int do_children) +/* This hook is used when running with --directory, when + we do use all the normal trivfs machinery. We just use + the normal trivfs open, but then stash the DOTDOT port + in the trivfs_peropen. */ + +static error_t +magic_open (struct trivfs_control *cntl, + struct iouser *user, + mach_port_t dotdot, + int flags, + mach_port_t realnode, + struct trivfs_protid **cred) { - return EOPNOTSUPP; + error_t err = trivfs_open (cntl, user, flags, realnode, cred); + if (!err) + { + (*cred)->po->hook = (void *) dotdot; + err = mach_port_mod_refs (mach_task_self (), dotdot, + MACH_PORT_RIGHT_SEND, +1); + assert_perror (err); + err = mach_port_deallocate (mach_task_self (), dotdot); + assert_perror (err); + } + return err; } + +/* Do a directory lookup. */ + error_t -S_fsys_get_options (mach_port_t control, - char **data, mach_msg_type_number_t *len) +trivfs_S_dir_lookup (struct trivfs_protid *cred, + mach_port_t reply, mach_msg_type_name_t reply_type, + char *name, + int flags, + mode_t mode, + retry_type *retry_type, + char *retry_name, + mach_port_t *retrypt, + mach_msg_type_name_t *retrypt_type) { - return EOPNOTSUPP; + int perms; + error_t err; + struct trivfs_protid *newcred; + mach_port_t dotdot; + struct iouser *user; + + if (!cred) + return EOPNOTSUPP; + + if (name[0] != '\0') + { + if (!directory) + return ENOTDIR; + else + { + /* We have a real lookup in the dummy directory. + Handle `.' and `..' specially, and anything else + gets redirected to the magical retry. */ + + while (*name == '/') + ++name; + while (!strncmp (name, "./", 2)) + { + name += 2; + while (*name == '/') + ++name; + } + + if (!strcmp (name, "..") || !strncmp (name, "../", 3)) + { + name += 2; + while (*name == '/') + ++name; + strcpy (retry_name, name); + *retry_type = FS_RETRY_REAUTH; + *retrypt = (mach_port_t) cred->po->hook; + *retrypt_type = MACH_MSG_TYPE_COPY_SEND; + return 0; + } + else if (name[0] != '\0' && strcmp (name, ".")) + { + char *p = stpcpy (retry_name, magic); + *p++ = '/'; + strcpy (p, name); + *retry_type = FS_RETRY_MAGICAL; + *retrypt = MACH_PORT_NULL; + *retrypt_type = MACH_MSG_TYPE_COPY_SEND; + return 0; + } + } + } + + /* This is a null-pathname "reopen" call; do the right thing. */ + + /* Burn off flags we don't actually implement */ + flags &= O_HURD; + flags &= ~(O_CREAT|O_EXCL|O_NOLINK|O_NOTRANS); + + /* Validate permissions */ + if (! trivfs_check_access_hook) + file_check_access (cred->realnode, &perms); + else + (*trivfs_check_access_hook) (cred->po->cntl, cred->user, + cred->realnode, &perms); + if ((flags & (O_READ|O_WRITE|O_EXEC) & perms) + != (flags & (O_READ|O_WRITE|O_EXEC))) + return EACCES; + + /* Execute the open */ + + dotdot = (mach_port_t) cred->po->hook; + user = iohelp_dup_iouser (cred->user); + err = magic_open (cred->po->cntl, user, dotdot, flags, + cred->realnode, &newcred); + if (err) + { + iohelp_free_iouser (user); + return err; + } + err = mach_port_mod_refs (mach_task_self (), dotdot, + MACH_PORT_RIGHT_SEND, +1); + assert_perror (err); + err = mach_port_mod_refs (mach_task_self (), cred->realnode, + MACH_PORT_RIGHT_SEND, +1); + assert_perror (err); + + *retry_type = FS_RETRY_NORMAL; + *retry_name = '\0'; + *retrypt = ports_get_right (newcred); + *retrypt_type = MACH_MSG_TYPE_MAKE_SEND; + ports_port_deref (newcred); + return 0; } error_t -S_fsys_getfile (mach_port_t control, - uid_t *uids, u_int nuids, uid_t *gids, u_int ngids, - char *handle, u_int handllen, - mach_port_t *pt, mach_msg_type_name_t *pttype) +trivfs_S_dir_readdir (struct trivfs_protid *cred, + mach_port_t reply, mach_msg_type_name_t reply_type, + char **data, + u_int *datalen, + boolean_t *data_dealloc, + int entry, + int nentries, + vm_size_t bufsiz, + int *amount) { - return EOPNOTSUPP; + if (!cred) + return EOPNOTSUPP; + + if (entry > 0) + { + void *p; + int i; + i = 0; + for (p = dirbuf; p < dirbuf + dirbufsize; + p += ((struct dirent *) p)->d_reclen) + if (++i == entry) + break; + *data = p; + *datalen = dirbuf + dirbufsize - p; + *amount = 2 - entry; + } + else + { + *data = dirbuf; + *datalen = dirbufsize; + *amount = 2; + } + + *data_dealloc = 0; + return 0; } -error_t -S_fsys_getpriv (mach_port_t control, - mach_port_t *host_priv, mach_msg_type_name_t *host_priv_type, - mach_port_t *dev_master, mach_msg_type_name_t *dev_master_type, - task_t *fs_task, mach_msg_type_name_t *fs_task_type) + + +static error_t +parse_opt (int opt, char *arg, struct argp_state *state) { - return EOPNOTSUPP; + switch (opt) + { + case 'd': + directory = 1; + return 0; + + case ARGP_KEY_NO_ARGS: + argp_usage (state); + return EINVAL; + + case ARGP_KEY_ARGS: + if (state->next != state->argc - 1) + { + argp_usage (state); + return EINVAL; + } + else + { + magic = state->argv[state->next]; + return 0; + } + break; + } + + return ARGP_ERR_UNKNOWN; } error_t -S_fsys_init (mach_port_t control, - mach_port_t reply, mach_msg_type_name_t replytype, - mach_port_t proc, auth_t auth) +trivfs_append_args (struct trivfs_control *fsys, + char **argz, size_t *argz_len) { - return EOPNOTSUPP; + return ((directory ? argz_add (argz, argz_len, "--directory") : 0) + ?: argz_add (argz, argz_len, magic)); } - -error_t -S_fsys_forward (mach_port_t server, mach_port_t requestor, - char *argz, size_t argz_len) + +int +main (int argc, char **argv) { - return EOPNOTSUPP; + error_t err; + mach_port_t bootstrap; + struct trivfs_control *fsys; + struct argp argp = { options, parse_opt, args_doc, doc }; + + argp_parse (&argp, argc, argv, 0, 0, 0); + + task_get_bootstrap_port (mach_task_self (), &bootstrap); + if (bootstrap == MACH_PORT_NULL) + error (1, 0, "Must be started as a translator"); + + /* Reply to our parent */ + err = trivfs_startup (bootstrap, 0, 0, 0, 0, 0, &fsys); + mach_port_deallocate (mach_task_self (), bootstrap); + if (err) + error (3, err, "Contacting parent"); + + if (directory) + { + inline struct dirent *add (struct dirent *d, const char *name) + { + d->d_fileno = 2; /* random */ + d->d_type = DT_DIR; + d->d_namlen = strlen (name); + strcpy (d->d_name, name); + d->d_name[d->d_namlen] = '\0'; + d->d_reclen = &d->d_name[d->d_namlen + 1] - (char *) d; + d->d_reclen = ((d->d_reclen + __alignof (struct dirent) - 1) + & ~(__alignof (struct dirent) - 1)); + return (struct dirent *) ((char *) d + d->d_reclen); + } + struct dirent *d; + dirbuf = mmap (0, getpagesize (), PROT_READ|PROT_WRITE, MAP_ANON, 0, 0); + d = add (dirbuf, "."); + d = add (d, ".."); + dirbufsize = (char *) d - (char *) dirbuf; + + trivfs_open_hook = &magic_open; + } + else + trivfs_getroot_hook = &magic_getroot; + + /* Launch. */ + ports_manage_port_operations_one_thread (fsys->pi.bucket, trivfs_demuxer, + 2 * 60 * 1000); + + return 0; } |