NetBSD/sbin/mount_portal/puffs_portal.c

784 lines
16 KiB
C

/* $NetBSD: puffs_portal.c,v 1.3 2009/12/19 16:01:25 pooka Exp $ */
/*
* Copyright (c) 2007 Antti Kantee. All Rights Reserved.
* Development was supported by the Finnish Cultural Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: puffs_portal.c,v 1.3 2009/12/19 16:01:25 pooka Exp $");
#endif /* !lint */
#include <sys/types.h>
#include <sys/wait.h>
#include <assert.h>
#include <err.h>
#include <errno.h>
#include <mntopts.h>
#include <paths.h>
#include <poll.h>
#include <puffs.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>
#include "portald.h"
struct portal_node {
char *path;
int fd;
};
static void usage(void);
PUFFSOP_PROTOS(portal);
#define PORTAL_ROOT NULL
#define METADATASIZE (sizeof(int) + sizeof(size_t))
qelem q;
int readcfg, sigchild;
const char *cfg;
static void
usage()
{
errx(1, "usage: %s [-o options] /path/portal.conf mount_point",
getprogname());
}
static void
sighup(int sig)
{
readcfg = 1;
}
static void
sigcry(int sig)
{
sigchild = 1;
}
static void
portal_loopfn(struct puffs_usermount *pu)
{
if (readcfg)
conf_read(&q, cfg);
readcfg = 0;
if (sigchild) {
sigchild = 0;
while (waitpid(-1, NULL, WNOHANG) != -1)
continue;
}
}
#define PUFBUF_FD 1
#define PUFBUF_DATA 2
#define CMSIZE (sizeof(struct cmsghdr) + sizeof(int))
/* receive file descriptor produced by our child process */
static int
readfd(struct puffs_framebuf *pufbuf, int fd, int *done)
{
struct cmsghdr *cmp;
struct msghdr msg;
struct iovec iov;
ssize_t n;
int error, rv;
rv = 0;
cmp = emalloc(CMSG_SPACE(sizeof(int)));
iov.iov_base = &error;
iov.iov_len = sizeof(int);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_control = cmp;
msg.msg_controllen = CMSG_SPACE(sizeof(int));
n = recvmsg(fd, &msg, 0);
if (n == -1) {
rv = errno;
goto out;
}
if (n == 0) {
rv = ECONNRESET;
goto out;
}
/* the data for the server */
puffs_framebuf_putdata_atoff(pufbuf, 0, &error, sizeof(int));
if (error) {
rv = error;
goto out;
}
puffs_framebuf_putdata_atoff(pufbuf, sizeof(int),
CMSG_DATA(cmp), sizeof(int));
*done = 1;
out:
free(cmp);
return rv;
}
/*
* receive data from provider
*
* XXX: should read directly into the buffer and adjust offsets
* instead of doing memcpy
*/
static int
readdata(struct puffs_framebuf *pufbuf, int fd, int *done)
{
char buf[1024];
size_t max;
ssize_t n;
size_t moved;
/* don't override metadata */
if (puffs_framebuf_telloff(pufbuf) == 0)
puffs_framebuf_seekset(pufbuf, METADATASIZE);
puffs_framebuf_getdata_atoff(pufbuf, sizeof(int), &max, sizeof(size_t));
moved = puffs_framebuf_tellsize(pufbuf) - METADATASIZE;
assert(max >= moved);
max -= moved;
do {
n = read(fd, buf, MIN(sizeof(buf), max));
if (n == 0) {
if (moved)
break;
else
return -1; /* caught by read */
}
if (n < 0) {
if (moved)
return 0;
if (errno != EAGAIN)
return errno;
else
return 0;
}
puffs_framebuf_putdata(pufbuf, buf, n);
moved += n;
max -= n;
} while (max > 0);
*done = 1;
return 0;
}
static int
portal_frame_rf(struct puffs_usermount *pu, struct puffs_framebuf *pufbuf,
int fd, int *done)
{
int type;
if (puffs_framebuf_getdata_atoff(pufbuf, 0, &type, sizeof(int)) == -1)
return EINVAL;
if (type == PUFBUF_FD)
return readfd(pufbuf, fd, done);
else if (type == PUFBUF_DATA)
return readdata(pufbuf, fd, done);
else
abort();
}
static int
portal_frame_wf(struct puffs_usermount *pu, struct puffs_framebuf *pufbuf,
int fd, int *done)
{
void *win;
size_t pbsize, pboff, winlen;
ssize_t n;
int error;
pboff = puffs_framebuf_telloff(pufbuf);
pbsize = puffs_framebuf_tellsize(pufbuf);
error = 0;
do {
assert(pbsize > pboff);
winlen = pbsize - pboff;
if (puffs_framebuf_getwindow(pufbuf, pboff, &win, &winlen)==-1)
return errno;
n = write(fd, win, winlen);
if (n == 0) {
if (pboff != 0)
break;
else
return -1; /* caught by node_write */
}
if (n < 0) {
if (pboff != 0)
break;
if (errno != EAGAIN)
return errno;
return 0;
}
pboff += n;
puffs_framebuf_seekset(pufbuf, pboff);
} while (pboff != pbsize);
*done = 1;
puffs_framebuf_putdata_atoff(pufbuf, 0, &pboff, sizeof(size_t));
return error;
}
/* transfer file descriptor to master file server */
static int
sendfd(int s, int fd, int error)
{
struct cmsghdr *cmp;
struct msghdr msg;
struct iovec iov;
ssize_t n;
int rv;
rv = 0;
cmp = emalloc(CMSG_LEN(sizeof(int)));
iov.iov_base = &error;
iov.iov_len = sizeof(int);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_name = NULL;
msg.msg_namelen = 0;
if (error == 0) {
cmp->cmsg_level = SOL_SOCKET;
cmp->cmsg_type = SCM_RIGHTS;
cmp->cmsg_len = CMSG_LEN(sizeof(int));
msg.msg_control = cmp;
msg.msg_controllen = CMSG_LEN(sizeof(int));
*(int *)CMSG_DATA(cmp) = fd;
} else {
msg.msg_control = NULL;
msg.msg_controllen = 0;
}
n = sendmsg(s, &msg, 0);
if (n == -1)
rv = errno;
else if (n < (ssize_t)sizeof(int))
rv = EPROTO;
free(cmp);
return rv;
}
/*
* Produce I/O file descriptor by forking (like original portald).
*
* child: run provider and transfer produced fd to parent
* parent: yield until child produces fd. receive it and store it.
*/
static int
provide(struct puffs_usermount *pu, struct portal_node *portn,
struct portal_cred *portc, char **v)
{
struct puffs_cc *pcc = puffs_cc_getcc(pu);
struct puffs_framebuf *pufbuf;
int s[2];
int fd, error;
int data;
pufbuf = puffs_framebuf_make();
if (pufbuf == NULL)
return ENOMEM;
data = PUFBUF_FD;
if (puffs_framebuf_putdata(pufbuf, &data, sizeof(int)) == -1)
goto bad;
if (socketpair(AF_LOCAL, SOCK_STREAM, 0, s) == -1)
goto bad;
switch (fork()) {
case -1:
goto bad;
case 0:
error = activate_argv(portc, portn->path, v, &fd);
sendfd(s[1], fd, error);
exit(0);
default:
puffs_framev_addfd(pu, s[0], PUFFS_FBIO_READ);
puffs_framev_enqueue_directreceive(pcc, s[0], pufbuf, 0);
puffs_framev_removefd(pu, s[0], 0);
close(s[0]);
close(s[1]);
if (puffs_framebuf_tellsize(pufbuf) < sizeof(int)) {
errno = EIO;
goto bad;
}
puffs_framebuf_getdata_atoff(pufbuf, 0, &error, sizeof(int));
if (error) {
errno = error;
goto bad;
}
if (puffs_framebuf_tellsize(pufbuf) != 2*sizeof(int)) {
errno = EIO;
goto bad;
}
puffs_framebuf_getdata_atoff(pufbuf, sizeof(int),
&fd, sizeof(int));
puffs_framebuf_destroy(pufbuf);
data = 1;
if (ioctl(fd, FIONBIO, &data) == -1)
return errno;
if (puffs_framev_addfd(pu, fd, PUFFS_FBIO_WRITE) == -1)
return errno;
portn->fd = fd;
return 0;
}
bad:
puffs_framebuf_destroy(pufbuf);
return errno;
}
int
main(int argc, char *argv[])
{
extern char *optarg;
extern int optind;
struct puffs_usermount *pu;
struct puffs_ops *pops;
mntoptparse_t mp;
int pflags, mntflags;
int detach;
int ch;
setprogname(argv[0]);
mntflags = pflags = 0;
detach = 1;
while ((ch = getopt(argc, argv, "o:s")) != -1) {
switch (ch) {
case 'o':
mp = getmntopts(optarg, puffsmopts, &mntflags, &pflags);
if (mp == NULL)
err(1, "getmntopts");
freemntopts(mp);
break;
case 's': /* stay on top */
detach = 0;
break;
default:
usage();
/*NOTREACHED*/
}
}
pflags |= PUFFS_KFLAG_NOCACHE | PUFFS_KFLAG_LOOKUP_FULLPNBUF;
if (pflags & PUFFS_FLAG_OPDUMP)
detach = 0;
argc -= optind;
argv += optind;
if (argc != 2)
usage();
PUFFSOP_INIT(pops);
PUFFSOP_SETFSNOP(pops, unmount);
PUFFSOP_SETFSNOP(pops, sync);
PUFFSOP_SETFSNOP(pops, statvfs);
PUFFSOP_SET(pops, portal, node, lookup);
PUFFSOP_SET(pops, portal, node, getattr);
PUFFSOP_SET(pops, portal, node, setattr);
PUFFSOP_SET(pops, portal, node, open);
PUFFSOP_SET(pops, portal, node, read);
PUFFSOP_SET(pops, portal, node, write);
PUFFSOP_SET(pops, portal, node, seek);
PUFFSOP_SET(pops, portal, node, poll);
PUFFSOP_SET(pops, portal, node, inactive);
PUFFSOP_SET(pops, portal, node, reclaim);
pu = puffs_init(pops, _PATH_PUFFS, "portal", NULL, pflags);
if (pu == NULL)
err(1, "init");
if (signal(SIGHUP, sighup) == SIG_ERR)
warn("cannot set sighup handler");
if (signal(SIGCHLD, sigcry) == SIG_ERR)
err(1, "cannot set sigchild handler");
if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
err(1, "cannot ignore sigpipe");
readcfg = 0;
cfg = argv[0];
if (*cfg != '/')
errx(1, "need absolute path for config");
q.q_forw = q.q_back = &q;
if (conf_read(&q, cfg) == -1)
err(1, "cannot read cfg \"%s\"", cfg);
puffs_ml_setloopfn(pu, portal_loopfn);
puffs_framev_init(pu, portal_frame_rf, portal_frame_wf, NULL,NULL,NULL);
if (detach)
if (puffs_daemon(pu, 1, 1) == -1)
err(1, "puffs_daemon");
if (puffs_mount(pu, argv[1], mntflags, PORTAL_ROOT) == -1)
err(1, "mount");
if (puffs_mainloop(pu) == -1)
err(1, "mainloop");
return 0;
}
static struct portal_node *
makenode(const char *path)
{
struct portal_node *portn;
portn = emalloc(sizeof(struct portal_node));
portn->path = estrdup(path);
portn->fd = -1;
return portn;
}
static void
credtr(struct portal_cred *portc, const struct puffs_cred *puffc, int mode)
{
memset(portc, 0, sizeof(struct portal_cred));
portc->pcr_flag = mode;
puffs_cred_getuid(puffc, &portc->pcr_uid);
puffs_cred_getgid(puffc, &portc->pcr_gid);
puffs_cred_getgroups(puffc, portc->pcr_groups,
(short *)&portc->pcr_ngroups);
}
/*
* XXX: we could also simply already resolve the name at this stage
* instead of deferring it to open. But doing it in open is how the
* original portald does it, and I don't want to introduce any funny
* incompatibilities.
*/
int
portal_node_lookup(struct puffs_usermount *pu, puffs_cookie_t opc,
struct puffs_newinfo *pni, const struct puffs_cn *pcn)
{
struct portal_node *portn;
assert(opc == PORTAL_ROOT);
if (pcn->pcn_nameiop != NAMEI_LOOKUP
&& pcn->pcn_nameiop != NAMEI_CREATE)
return EOPNOTSUPP;
portn = makenode(pcn->pcn_name);
puffs_newinfo_setcookie(pni, portn);
puffs_newinfo_setvtype(pni, VREG);
pcn->pcn_flags &= ~NAMEI_REQUIREDIR;
pcn->pcn_consume = strlen(pcn->pcn_name) - pcn->pcn_namelen;
return 0;
}
int fakeid = 3;
/* XXX: libpuffs'ize */
int
portal_node_getattr(struct puffs_usermount *pu, puffs_cookie_t opc,
struct vattr *va, const struct puffs_cred *pcr)
{
struct timeval tv;
struct timespec ts;
puffs_vattr_null(va);
if (opc == PORTAL_ROOT) {
va->va_type = VDIR;
va->va_mode = 0777;
va->va_nlink = 2;
} else {
va->va_type = VREG;
va->va_mode = 0666;
va->va_nlink = 1;
}
va->va_uid = va->va_gid = 0;
va->va_fileid = fakeid++;
va->va_size = va->va_bytes = 0;
va->va_gen = 0;
va->va_rdev = PUFFS_VNOVAL;
va->va_blocksize = DEV_BSIZE;
gettimeofday(&tv, NULL);
TIMEVAL_TO_TIMESPEC(&tv, &ts);
va->va_atime = va->va_ctime = va->va_mtime = va->va_birthtime = ts;
return 0;
}
/* for writing, just pretend we care */
int
portal_node_setattr(struct puffs_usermount *pu, puffs_cookie_t opc,
const struct vattr *va, const struct puffs_cred *pcr)
{
return 0;
}
int
portal_node_open(struct puffs_usermount *pu, puffs_cookie_t opc, int mode,
const struct puffs_cred *pcr)
{
struct portal_node *portn = opc;
struct portal_cred portc;
char **v;
if (opc == PORTAL_ROOT)
return 0;
if (mode & O_NONBLOCK)
return EOPNOTSUPP;
v = conf_match(&q, portn->path);
if (v == NULL)
return ENOENT;
credtr(&portc, pcr, mode);
return provide(pu, portn, &portc, v);
}
int
portal_node_read(struct puffs_usermount *pu, puffs_cookie_t opc,
uint8_t *buf, off_t offset, size_t *resid,
const struct puffs_cred *pcr, int ioflag)
{
struct puffs_cc *pcc = puffs_cc_getcc(pu);
struct portal_node *portn = opc;
struct puffs_framebuf *pufbuf;
size_t xfersize, winsize, boff;
void *win;
int rv, error;
int data, dummy;
assert(opc != PORTAL_ROOT);
error = 0;
/* if we can't (re-)enable it, treat it as EOF */
rv = puffs_framev_enablefd(pu, portn->fd, PUFFS_FBIO_READ);
if (rv == -1)
return 0;
pufbuf = puffs_framebuf_make();
data = PUFBUF_DATA;
puffs_framebuf_putdata(pufbuf, &data, sizeof(int));
puffs_framebuf_putdata(pufbuf, resid, sizeof(size_t));
/* if we are doing nodelay, do read directly */
if (ioflag & PUFFS_IO_NDELAY) {
rv = readdata(pufbuf, portn->fd, &dummy);
if (rv != 0) {
error = rv;
goto out;
}
} else {
rv = puffs_framev_enqueue_directreceive(pcc,
portn->fd, pufbuf, 0);
if (rv == -1) {
error = errno;
goto out;
}
}
xfersize = puffs_framebuf_tellsize(pufbuf) - METADATASIZE;
if (xfersize == 0) {
assert(ioflag & PUFFS_IO_NDELAY);
error = EAGAIN;
goto out;
}
*resid -= xfersize;
boff = 0;
while (xfersize > 0) {
winsize = xfersize;
rv = puffs_framebuf_getwindow(pufbuf, METADATASIZE,
&win, &winsize);
assert(rv == 0);
assert(winsize > 0);
memcpy(buf + boff, win, winsize);
xfersize -= winsize;
boff += winsize;
}
out:
puffs_framev_disablefd(pu, portn->fd, PUFFS_FBIO_READ);
puffs_framebuf_destroy(pufbuf);
/* a trickery, from readdata() */
if (error == -1)
return 0;
return error;
}
int
portal_node_write(struct puffs_usermount *pu, puffs_cookie_t opc,
uint8_t *buf, off_t offset, size_t *resid,
const struct puffs_cred *pcr, int ioflag)
{
struct puffs_cc *pcc = puffs_cc_getcc(pu);
struct portal_node *portn = opc;
struct puffs_framebuf *pufbuf;
size_t written;
int error, rv, dummy;
assert(opc != PORTAL_ROOT);
pufbuf = puffs_framebuf_make();
puffs_framebuf_putdata(pufbuf, buf, *resid);
error = 0;
if (ioflag & PUFFS_IO_NDELAY) {
rv = portal_frame_wf(pu, pufbuf, portn->fd, &dummy);
if (rv) {
error = rv;
goto out;
}
} else {
rv = puffs_framev_enqueue_directsend(pcc, portn->fd, pufbuf, 0);
if (rv == -1) {
error = errno;
goto out;
}
}
rv = puffs_framebuf_getdata_atoff(pufbuf, 0, &written, sizeof(size_t));
assert(rv == 0);
assert(written <= *resid);
*resid -= written;
out:
puffs_framebuf_destroy(pufbuf);
if (error == -1)
error = 0;
return 0;
}
int
portal_node_seek(struct puffs_usermount *pu, puffs_cookie_t opc,
off_t oldoff, off_t newoff, const struct puffs_cred *pcr)
{
struct portal_node *portn = opc;
if (opc == PORTAL_ROOT || portn->fd == -1)
return EOPNOTSUPP;
if (lseek(portn->fd, newoff, SEEK_SET) == -1)
return errno;
return 0;
}
int
portal_node_poll(struct puffs_usermount *pu, puffs_cookie_t opc, int *events)
{
struct puffs_cc *pcc = puffs_cc_getcc(pu);
struct portal_node *portn = opc;
int what;
int rv;
what = 0;
if (*events & POLLIN)
what |= PUFFS_FBIO_READ;
if (*events & POLLOUT)
what |= PUFFS_FBIO_WRITE;
if (*events & POLLERR)
what |= PUFFS_FBIO_ERROR;
rv = puffs_framev_enqueue_waitevent(pcc, portn->fd, &what);
if (rv) {
*events = POLLERR;
return rv;
}
*events = 0;
if (what & PUFFS_FBIO_READ)
*events |= POLLIN;
if (what & PUFFS_FBIO_WRITE)
*events |= POLLOUT;
if (what & PUFFS_FBIO_ERROR)
*events |= POLLERR;
return 0;
}
int
portal_node_inactive(struct puffs_usermount *pu, puffs_cookie_t opc)
{
if (opc == PORTAL_ROOT)
return 0;
puffs_setback(puffs_cc_getcc(pu), PUFFS_SETBACK_NOREF_N1);
return 0;
}
int
portal_node_reclaim(struct puffs_usermount *pu, puffs_cookie_t opc)
{
struct portal_node *portn = opc;
if (portn->fd != -1) {
puffs_framev_removefd(pu, portn->fd, 0);
close(portn->fd);
}
free(portn->path);
free(portn);
return 0;
}