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UDS: clean up source code

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- move VFS calls to a separate source file;
- solve a few subtle bugs, mostly in error handling;
- simplify debug reporting code;
- make a few definitions more independent;
- restyle to something closer to KNF.

Change-Id: I7b0537adfccac8b92b5cc3e78dac9f5ce3c79f03
This commit is contained in:
David van Moolenbroek 2013-10-04 16:46:18 +02:00 committed by Lionel Sambuc
parent b003ed0929
commit 1e07186caf
5 changed files with 747 additions and 1186 deletions
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2
drivers/uds/Makefile
View file

@ -1,6 +1,6 @@
# Makefile for the UNIX Domain Sockets driver (UDS)
PROG= uds
SRCS= uds.c ioc_uds.c
SRCS= uds.c ioc_uds.c vfs_uds.c
DPADD+= ${LIBCHARDRIVER} ${LIBSYS}
LDADD+= -lchardriver -lsys

1228
drivers/uds/ioc_uds.c
View file

File diff suppressed because it is too large Load diff

387
drivers/uds/uds.c
View file

@ -50,32 +50,23 @@ uds_open(devminor_t UNUSED(orig_minor), int access,
endpoint_t user_endpt)
{
devminor_t minor;
int i;
char *buf;
int i;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [-] uds_open() call_count=%d\n", ++call_count);
printf("Endpoint: 0x%x\n", user_endpt);
#endif
dprintf(("UDS: uds_open() from %d\n", user_endpt));
/*
* Find a slot in the descriptor table for the new descriptor.
* The index of the descriptor in the table will be returned.
* Subsequent calls to read/write/close/ioctl/etc will use this
* minor number. The minor number must be different from the
* the /dev/uds device's minor number (currently 0).
* the /dev/uds device's minor number (0).
*/
minor = -1; /* to trap error */
for (i = 1; i < NR_FDS; i++) {
if (uds_fd_table[i].state == UDS_FREE) {
minor = i;
for (minor = 1; minor < NR_FDS; minor++)
if (uds_fd_table[minor].state == UDS_FREE)
break;
}
}
if (minor == -1)
if (minor == NR_FDS)
return ENFILE;
/*
@ -84,69 +75,40 @@ uds_open(devminor_t UNUSED(orig_minor), int access,
* in use. We use mmap instead of malloc to allow the memory to be
* actually freed later.
*/
if ((buf = minix_mmap(NULL, PIPE_BUF, PROT_READ | PROT_WRITE,
if ((buf = minix_mmap(NULL, UDS_BUF, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_PRIVATE, -1, 0)) == MAP_FAILED)
return ENOMEM;
/* mark this one as 'in use' so that it doesn't get assigned to
* another socket
/*
* Allocate the socket, and set its initial parameters.
*/
uds_fd_table[minor].state = UDS_INUSE;
/* set the socket owner */
uds_fd_table[minor].owner = user_endpt;
/* setup select(2) framework */
uds_fd_table[minor].sel_endpt = NONE;
uds_fd_table[minor].sel_ops = 0;
uds_fd_table[minor].buf = buf;
uds_fd_table[minor].pos = 0;
/* the PIPE is initially empty */
uds_fd_table[minor].size = 0;
/* the default for a new socket is to allow reading and writing.
* shutdown(2) will remove one or both flags.
*/
uds_fd_table[minor].mode = R_BIT | W_BIT;
/* In libc socket(2) sets this to the actual value later with the
* NWIOSUDSTYPE ioctl().
*/
uds_fd_table[minor].mode = UDS_R | UDS_W;
uds_fd_table[minor].type = -1;
/* Clear the backlog by setting each entry to -1 */
for (i = 0; i < UDS_SOMAXCONN; i++) {
/* initially no connections are pending */
for (i = 0; i < UDS_SOMAXCONN; i++)
uds_fd_table[minor].backlog[i] = -1;
}
memset(&uds_fd_table[minor].ancillary_data, '\0', sizeof(struct
ancillary));
for (i = 0; i < OPEN_MAX; i++) {
uds_fd_table[minor].ancillary_data.fds[i] = -1;
}
/* default the size to UDS_SOMAXCONN */
uds_fd_table[minor].backlog_size = UDS_SOMAXCONN;
/* the socket isn't listening for incoming connections until
* listen(2) is called
*/
memset(&uds_fd_table[minor].ancillary_data, '\0',
sizeof(struct ancillary));
for (i = 0; i < OPEN_MAX; i++)
uds_fd_table[minor].ancillary_data.fds[i] = -1;
uds_fd_table[minor].listening = 0;
/* initially the socket is not connected to a peer */
uds_fd_table[minor].peer = -1;
/* there isn't a child waiting to be accept(2)'d */
uds_fd_table[minor].child = -1;
/* initially the socket is not bound or listening on an address */
memset(&(uds_fd_table[minor].addr), '\0', sizeof(struct sockaddr_un));
memset(&(uds_fd_table[minor].source), '\0', sizeof(struct sockaddr_un));
memset(&(uds_fd_table[minor].target), '\0', sizeof(struct sockaddr_un));
memset(&uds_fd_table[minor].addr, '\0', sizeof(struct sockaddr_un));
memset(&uds_fd_table[minor].source, '\0', sizeof(struct sockaddr_un));
memset(&uds_fd_table[minor].target, '\0', sizeof(struct sockaddr_un));
/* Initially the socket isn't suspended. */
uds_fd_table[minor].suspended = UDS_NOT_SUSPENDED;
return CDEV_CLONED | minor;
@ -157,41 +119,32 @@ uds_close(devminor_t minor)
{
int peer;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_close() call_count=%d\n", minor, ++call_count);
#endif
dprintf(("UDS: uds_close(%d)\n", minor));
if (minor < 0 || minor >= NR_FDS) return ENXIO;
if (uds_fd_table[minor].state != UDS_INUSE) {
/* attempted to close a socket that hasn't been opened --
* something is very wrong :(
*/
if (uds_fd_table[minor].state != UDS_INUSE)
return EINVAL;
}
/* if the socket is connected, disconnect it */
/* If the socket is connected, disconnect it. */
if (uds_fd_table[minor].peer != -1) {
peer = uds_fd_table[minor].peer;
/* set peer of this peer to -1 */
uds_fd_table[peer].peer = -1;
/* error to pass to peer */
/* The error to pass to the peer. */
uds_fd_table[peer].err = ECONNRESET;
/* if peer was blocked on I/O revive peer */
/* If the peer was blocked on I/O, revive it. */
if (uds_fd_table[peer].suspended != UDS_NOT_SUSPENDED)
uds_unsuspend(peer);
}
if (uds_fd_table[minor].ancillary_data.nfiledes > 0) {
if (uds_fd_table[minor].ancillary_data.nfiledes > 0)
uds_clear_fds(minor, &uds_fd_table[minor].ancillary_data);
}
/* Release the memory for the ring buffer. */
minix_munmap(uds_fd_table[minor].buf, PIPE_BUF);
minix_munmap(uds_fd_table[minor].buf, UDS_BUF);
/* Set the socket back to its original UDS_FREE state. */
memset(&uds_fd_table[minor], '\0', sizeof(uds_fd_t));
@ -211,33 +164,25 @@ uds_select(devminor_t minor, unsigned int ops, endpoint_t endpt)
unsigned int ready_ops;
int i, bytes, watch;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_select() call_count=%d\n", minor, ++call_count);
#endif
dprintf(("UDS: uds_select(%d)\n", minor));
if (minor < 0 || minor >= NR_FDS) return ENXIO;
if (uds_fd_table[minor].state != UDS_INUSE) {
/* attempted to select on a socket that hasn't been opened --
* something is very wrong :(
*/
if (uds_fd_table[minor].state != UDS_INUSE)
return EINVAL;
}
watch = (ops & CDEV_NOTIFY);
ops &= (CDEV_OP_RD | CDEV_OP_WR | CDEV_OP_ERR);
ready_ops = 0;
/* check if there is data available to read */
/* Check if there is data available to read. */
if (ops & CDEV_OP_RD) {
bytes = uds_perform_read(minor, NONE, GRANT_INVALID, 1, 1);
if (bytes > 0) {
/* there is data in the pipe for us to read */
ready_ops |= CDEV_OP_RD;
ready_ops |= CDEV_OP_RD; /* data available */
} else if (uds_fd_table[minor].listening == 1) {
/* check for pending connections */
/* Check for pending connections. */
for (i = 0; i < uds_fd_table[minor].backlog_size; i++)
{
if (uds_fd_table[minor].backlog[i] != -1) {
@ -246,22 +191,19 @@ uds_select(devminor_t minor, unsigned int ops, endpoint_t endpt)
}
}
} else if (bytes != SUSPEND) {
ready_ops |= CDEV_OP_RD;
ready_ops |= CDEV_OP_RD; /* error */
}
}
/* check if we can write without blocking */
/* Check if we can write without blocking. */
if (ops & CDEV_OP_WR) {
bytes = uds_perform_write(minor, NONE, GRANT_INVALID, 1, 1);
if (bytes != 0 && bytes != SUSPEND) {
/* There is room to write or there is an error
* condition.
*/
if (bytes != 0 && bytes != SUSPEND)
ready_ops |= CDEV_OP_WR;
}
}
/* If not all requested ops were ready, and the caller requests to be
/*
* If not all requested ops were ready, and the caller requests to be
* notified about changes, we add the remaining ops to the saved set.
*/
ops &= ~ready_ops;
@ -280,64 +222,50 @@ uds_perform_read(devminor_t minor, endpoint_t endpt, cp_grant_id_t grant,
size_t pos, subsize;
int r, peer;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_perform_read() call_count=%d\n", minor,
++call_count);
#endif
dprintf(("UDS: uds_perform_read(%d)\n", minor));
peer = uds_fd_table[minor].peer;
/* skip reads and writes of 0 (or less!) bytes */
if (size <= 0) {
/* Skip reads of zero bytes. */
if (size == 0)
return 0;
}
/* check if we are allowed to read */
if (!(uds_fd_table[minor].mode & R_BIT)) {
/* socket is shutdown for reading */
/* Check if the socket isn't shut down for reads. */
if (!(uds_fd_table[minor].mode & UDS_R))
return EPIPE;
}
if (uds_fd_table[minor].size == 0) {
if (peer == -1) {
/* We're not connected. That's only a problem when this
* socket is connection oriented. */
/*
* We're not connected. That's only a problem when this
* socket is connection oriented.
*/
if (uds_fd_table[minor].type == SOCK_STREAM ||
uds_fd_table[minor].type == SOCK_SEQPACKET) {
if (uds_fd_table[minor].err == ECONNRESET) {
if (!pretend)
uds_fd_table[minor].err = 0;
return ECONNRESET;
} else {
} else
return ENOTCONN;
}
}
}
/* Check if process is reading from a closed pipe */
if (peer != -1 && !(uds_fd_table[peer].mode & W_BIT) &&
uds_fd_table[minor].size == 0) {
/* Check if process is reading from a closed pipe. */
if (peer != -1 && !(uds_fd_table[peer].mode & UDS_W) &&
uds_fd_table[minor].size == 0)
return 0;
}
if (pretend) {
if (pretend)
return SUSPEND;
}
/* maybe a process is blocked waiting to write? if
* needed revive the writer
*/
if (peer != -1 &&
uds_fd_table[peer].suspended == UDS_SUSPENDED_WRITE)
uds_unsuspend(peer);
panic("writer blocked on empty socket");
#if DEBUG == 1
printf("(uds) [%d] suspending read request\n", minor);
#endif
/* Process is reading from an empty pipe,
* suspend it so some bytes can be written
*/
dprintf(("UDS: suspending read request on %d\n", minor));
/* Process is reading from an empty pipe. Suspend it. */
return EDONTREPLY;
}
@ -351,7 +279,7 @@ uds_perform_read(devminor_t minor, endpoint_t endpt, cp_grant_id_t grant,
/* Get the data from the tail of the ring buffer. */
pos = uds_fd_table[minor].pos;
subsize = PIPE_BUF - pos;
subsize = UDS_BUF - pos;
if (subsize > size)
subsize = size;
@ -367,35 +295,27 @@ uds_perform_read(devminor_t minor, endpoint_t endpt, cp_grant_id_t grant,
}
/* Advance the buffer tail. */
uds_fd_table[minor].pos = (pos + size) % PIPE_BUF;
uds_fd_table[minor].pos = (pos + size) % UDS_BUF;
uds_fd_table[minor].size -= size;
/* if we have 0 unread bytes, move the data pointer back to the
* start of the buffer
*/
if (uds_fd_table[minor].size == 0) {
/* Reset position if the buffer is empty (it may save a copy call). */
if (uds_fd_table[minor].size == 0)
uds_fd_table[minor].pos = 0;
}
/* maybe a big write was waiting for us to read some data, if
* needed revive the writer
*/
/* See if we can wake up a blocked writer. */
if (peer != -1 && uds_fd_table[peer].suspended == UDS_SUSPENDED_WRITE)
uds_unsuspend(peer);
/* see if peer is blocked on select() and a write is possible (from
* peer to minor); if the peer wants to know about write being possible
* and it doesn't know about it already, then let the peer know.
*/
/* See if we can satisfy an ongoing select. */
if (peer != -1 && (uds_fd_table[peer].sel_ops & CDEV_OP_WR) &&
size > 0) {
/* a write on peer is possible now */
uds_fd_table[minor].size < UDS_BUF) {
/* A write on the peer is possible now. */
chardriver_reply_select(uds_fd_table[peer].sel_endpt, peer,
CDEV_OP_WR);
uds_fd_table[peer].sel_ops &= ~CDEV_OP_WR;
}
return size; /* return number of bytes read */
return size; /* number of bytes read */
}
static ssize_t
@ -405,62 +325,53 @@ uds_perform_write(devminor_t minor, endpoint_t endpt, cp_grant_id_t grant,
size_t subsize, pos;
int i, r, peer;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_perform_write() call_count=%d\n", minor,
++call_count);
#endif
dprintf(("UDS: uds_perform_write(%d)\n", minor));
/* Skip writes of zero bytes. */
if (size == 0)
return 0;
/* check if we are allowed to write */
if (!(uds_fd_table[minor].mode & W_BIT)) {
/* socket is shutdown for writing */
/* Check if the socket isn't shut down for writes. */
if (!(uds_fd_table[minor].mode & UDS_W))
return EPIPE;
}
if (size > PIPE_BUF) {
/* message is too big to ever write to the PIPE */
/* We cannot handle input beyond the buffer size. */
if (size > UDS_BUF)
return EMSGSIZE;
}
if (uds_fd_table[minor].type == SOCK_STREAM ||
uds_fd_table[minor].type == SOCK_SEQPACKET) {
/* if we're writing with a connection oriented socket,
* then it needs a peer to write to
/*
* If we're writing to a connection-oriented socket,
* then it needs a peer to write to.
*/
if (uds_fd_table[minor].peer == -1) {
if (uds_fd_table[minor].err == ECONNRESET) {
peer = uds_fd_table[minor].peer;
if (peer == -1) {
if (uds_fd_table[minor].err == ECONNRESET) {
if (!pretend)
uds_fd_table[minor].err = 0;
return ECONNRESET;
} else {
} else
return ENOTCONN;
}
} else {
peer = uds_fd_table[minor].peer;
}
} else /* uds_fd_table[minor].type == SOCK_DGRAM */ {
peer = -1;
/* locate the "peer" we want to write to */
/* Locate the "peer" we want to write to. */
for (i = 0; i < NR_FDS; i++) {
/* look for a SOCK_DGRAM socket that is bound on
* the target address
/*
* Look for a SOCK_DGRAM socket that is bound on
* the target address.
*/
if (uds_fd_table[i].type == SOCK_DGRAM &&
uds_fd_table[i].addr.sun_family == AF_UNIX &&
!strncmp(uds_fd_table[minor].target.sun_path,
uds_fd_table[i].addr.sun_path, UNIX_PATH_MAX)) {
peer = i;
break;
}
}
}
if (peer == -1) {
if (pretend)
@ -468,57 +379,50 @@ uds_perform_write(devminor_t minor, endpoint_t endpt, cp_grant_id_t grant,
return ENOENT;
}
}
/* check if we write to a closed pipe */
if (!(uds_fd_table[peer].mode & R_BIT)) {
/* Check if we write to a closed pipe. */
if (!(uds_fd_table[peer].mode & UDS_R))
return EPIPE;
}
/* we have to preserve the boundary for DGRAM. if there's
* already a packet waiting, discard it silently and pretend
* it was written.
/*
* We have to preserve the boundary for DGRAM. If there's already a
* packet waiting, discard it silently and pretend it was written.
*/
if(uds_fd_table[minor].type == SOCK_DGRAM &&
uds_fd_table[peer].size > 0) {
if (uds_fd_table[minor].type == SOCK_DGRAM &&
uds_fd_table[peer].size > 0)
return size;
}
/*
* Check if the ring buffer is already full, and if the SEQPACKET
* message wouldn't write to an empty buffer.
*/
if (uds_fd_table[peer].size == PIPE_BUF ||
if (uds_fd_table[peer].size == UDS_BUF ||
(uds_fd_table[minor].type == SOCK_SEQPACKET &&
uds_fd_table[peer].size > 0)) {
if (pretend) {
if (pretend)
return SUSPEND;
}
/* if needed revive the reader */
if (uds_fd_table[peer].suspended == UDS_SUSPENDED_READ)
uds_unsuspend(peer);
panic("reader blocked on full socket");
#if DEBUG == 1
printf("(uds) [%d] suspending write request\n", minor);
#endif
dprintf(("UDS: suspending write request on %d\n", minor));
/* Process is reading from an empty pipe,
* suspend it so some bytes can be written
*/
/* Process is reading from an empty pipe. Suspend it. */
return EDONTREPLY;
}
/* How much can we add to the ring buffer? */
if (size > PIPE_BUF - uds_fd_table[peer].size)
size = PIPE_BUF - uds_fd_table[peer].size;
if (size > UDS_BUF - uds_fd_table[peer].size)
size = UDS_BUF - uds_fd_table[peer].size;
if (pretend)
return size;
/* Put the data at the head of the ring buffer. */
pos = (uds_fd_table[peer].pos + uds_fd_table[peer].size) % PIPE_BUF;
pos = (uds_fd_table[peer].pos + uds_fd_table[peer].size) % UDS_BUF;
subsize = PIPE_BUF - pos;
subsize = UDS_BUF - pos;
if (subsize > size)
subsize = size;
@ -535,28 +439,25 @@ uds_perform_write(devminor_t minor, endpoint_t endpt, cp_grant_id_t grant,
/* Advance the buffer head. */
uds_fd_table[peer].size += size;
/* fill in the source address to be returned by recvfrom & recvmsg */
if (uds_fd_table[minor].type == SOCK_DGRAM) {
/* Fill in the source address to be returned by recvfrom, recvmsg. */
if (uds_fd_table[minor].type == SOCK_DGRAM)
memcpy(&uds_fd_table[peer].source, &uds_fd_table[minor].addr,
sizeof(struct sockaddr_un));
}
/* revive peer that was waiting for us to write */
/* See if we can wake up a blocked reader. */
if (uds_fd_table[peer].suspended == UDS_SUSPENDED_READ)
uds_unsuspend(peer);
/* see if peer is blocked on select(); if the peer wants to know about
* data ready to read and it doesn't know about it already, then let
* the peer know we have data for it.
*/
if ((uds_fd_table[peer].sel_ops & CDEV_OP_RD) && size > 0) {
/* a read on peer is possible now */
/* See if we can satisfy an ongoing select. */
if ((uds_fd_table[peer].sel_ops & CDEV_OP_RD) &&
uds_fd_table[peer].size > 0) {
/* A read on the peer is possible now. */
chardriver_reply_select(uds_fd_table[peer].sel_endpt, peer,
CDEV_OP_RD);
uds_fd_table[peer].sel_ops &= ~CDEV_OP_RD;
}
return size; /* return number of bytes written */
return size; /* number of bytes written */
}
static ssize_t
@ -565,19 +466,12 @@ uds_read(devminor_t minor, u64_t position, endpoint_t endpt,
{
ssize_t rc;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_read() call_count=%d\n", minor, ++call_count);
#endif
dprintf(("UDS: uds_read(%d)\n", minor));
if (minor < 0 || minor >= NR_FDS) return ENXIO;
if (uds_fd_table[minor].state != UDS_INUSE) {
/* attempted to read from a socket that hasn't been opened --
* something is very wrong :(
*/
if (uds_fd_table[minor].state != UDS_INUSE)
return EINVAL;
}
rc = uds_perform_read(minor, endpt, grant, size, 0);
@ -606,19 +500,12 @@ uds_write(devminor_t minor, u64_t position, endpoint_t endpt,
{
ssize_t rc;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_write() call_count=%d\n", minor, ++call_count);
#endif
dprintf(("UDS: uds_write(%d)\n", minor));
if (minor < 0 || minor >= NR_FDS) return ENXIO;
if (uds_fd_table[minor].state != UDS_INUSE) {
/* attempted to write to a socket that hasn't been opened --
* something is very wrong :(
*/
if (uds_fd_table[minor].state != UDS_INUSE)
return EINVAL;
}
rc = uds_perform_write(minor, endpt, grant, size, 0);
@ -647,24 +534,17 @@ uds_ioctl(devminor_t minor, unsigned long request, endpoint_t endpt,
{
int rc;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_ioctl() call_count=%d\n", minor, ++call_count);
#endif
dprintf(("UDS: uds_ioctl(%d, %lu)\n", minor, request));
if (minor < 0 || minor >= NR_FDS) return ENXIO;
if (uds_fd_table[minor].state != UDS_INUSE) {
/* attempted to perform I/O control on a socket that hasn't
* been opened -- something is very wrong :(
*/
if (uds_fd_table[minor].state != UDS_INUSE)
return EINVAL;
}
/* update the owner endpoint */
/* Update the owner endpoint. */
uds_fd_table[minor].owner = user_endpt;
/* let the UDS subsystem handle the actual request */
/* Let the UDS ioctl subsystem handle the actual request. */
rc = uds_do_ioctl(minor, request, endpt, grant);
/* If the call couldn't complete, suspend the caller. */
@ -717,7 +597,8 @@ uds_unsuspend(devminor_t minor)
case UDS_SUSPENDED_CONNECT:
case UDS_SUSPENDED_ACCEPT:
/* In both cases, the caller already set up the connection.
/*
* In both cases, the caller already set up the connection.
* The only thing to do here is unblock.
*/
r = OK;
@ -739,10 +620,7 @@ uds_cancel(devminor_t minor, endpoint_t endpt, cdev_id_t id)
uds_fd_t *fdp;
int i, j;
#if DEBUG == 1
static int call_count = 0;
printf("(uds) [%d] uds_cancel() call_count=%d\n", minor, ++call_count);
#endif
dprintf(("UDS: uds_cancel(%d)\n", minor));
if (minor < 0 || minor >= NR_FDS) return EDONTREPLY;
@ -755,47 +633,40 @@ uds_cancel(devminor_t minor, endpoint_t endpt, cdev_id_t id)
/* Make sure the cancel request is for a request we're hanging on. */
if (fdp->suspended == UDS_NOT_SUSPENDED || fdp->susp_endpt != endpt ||
fdp->susp_id != id) {
fdp->susp_id != id)
return EDONTREPLY; /* this happens. */
}
/* The system call was cancelled, so the socket is not suspended
/*
* The system call was cancelled, so the socket is not suspended
* anymore.
*/
switch (fdp->suspended) {
case UDS_SUSPENDED_ACCEPT: /* accept() */
/* partial accept() only changes
* uds_fd_table[minorparent].child
*/
for (i = 0; i < NR_FDS; i++) {
if (uds_fd_table[i].child == minor) {
/* A partial accept() only sets the server's child. */
for (i = 0; i < NR_FDS; i++)
if (uds_fd_table[i].child == minor)
uds_fd_table[i].child = -1;
}
}
break;
case UDS_SUSPENDED_CONNECT: /* connect() */
/* partial connect() sets addr and adds minor to server backlog
/*
* A partial connect() sets the address and adds the minor to
* the server backlog.
*/
for (i = 0; i < NR_FDS; i++) {
/* find a socket that is in use. */
if (uds_fd_table[i].state != UDS_INUSE)
continue;
/* see if minor is in the backlog */
/* Remove the minor from the backlog of any server. */
for (j = 0; j < uds_fd_table[i].backlog_size; j++) {
if (uds_fd_table[i].backlog[j] == minor) {
/* remove from backlog */
if (uds_fd_table[i].backlog[j] == minor)
uds_fd_table[i].backlog[j] = -1;
}
}
}
/* clear the address */
memset(&(uds_fd_table[minor].addr), '\0',
/* Clear the address. */
memset(&uds_fd_table[minor].addr, '\0',
sizeof(struct sockaddr_un));
break;

32
drivers/uds/uds.h
View file

@ -16,9 +16,18 @@
/* Connection backlog size for incoming connections. */
#define UDS_SOMAXCONN 64
/* Maximum UDS socket buffer size. */
#define UDS_BUF PIPE_BUF
/* Output debugging information? */
#define DEBUG 0
#if DEBUG
#define dprintf(x) printf x
#else
#define dprintf(x)
#endif
typedef void* filp_id_t;
/* ancillary data to be sent */
@ -29,6 +38,9 @@ struct ancillary {
struct uucred cred;
};
#define UDS_R 0x1
#define UDS_W 0x2
/*
* Internal State Information for a socket descriptor.
*/
@ -61,9 +73,9 @@ struct uds_fd {
size_t size; /* size of used part of ring buffer */
/* control read/write, set by uds_open() and shutdown(2).
* Can be set to R_BIT|W_BIT, R_BIT, W_BIT, or 0
* Can be set to UDS_R|UDS_W, UDS_R, UDS_W, or 0
* for read and write, read only, write only, or neither.
* default is R_BIT|W_BIT.
* default is UDS_R|UDS_W.
*/
int mode;
@ -179,12 +191,20 @@ EXTERN uds_fd_t uds_fd_table[NR_FDS];
/* Function prototypes. */
/* dev_uds.c */
void uds_unsuspend(devminor_t minor);
/* uds.c */
/* ioc_uds.c */
int uds_clear_fds(devminor_t minor, struct ancillary *data);
int uds_do_ioctl(devminor_t minor, unsigned long request, endpoint_t endpt,
cp_grant_id_t grant);
/* uds.c */
void uds_unsuspend(devminor_t minor);
/* vfs_uds.c */
int vfs_check_perms(endpoint_t ep, struct sockaddr_un *addr);
int vfs_verify_fd(endpoint_t ep, int fd, filp_id_t *filp);
int vfs_set_filp(filp_id_t sfilp);
int vfs_copy_filp(endpoint_t to_ep, filp_id_t cfilp);
int vfs_put_filp(filp_id_t pfilp);
int vfs_cancel_fd(endpoint_t ep, int fd);
#endif /* !__UDS_UDS_H */

168
drivers/uds/vfs_uds.c Normal file
View file

@ -0,0 +1,168 @@
/*
* Unix Domain Sockets Implementation (PF_UNIX, PF_LOCAL)
* This code provides communication stubs for backcalls to VFS.
*/
#include "uds.h"
/*
* Check the permissions of a socket file.
*/
int
vfs_check_perms(endpoint_t ep, struct sockaddr_un *addr)
{
int rc;
message m;
cp_grant_id_t grant_id;
dprintf(("UDS: vfs_check_perms(%d)\n", ep));
grant_id = cpf_grant_direct(VFS_PROC_NR, (vir_bytes) addr->sun_path,
UNIX_PATH_MAX, CPF_READ | CPF_WRITE);
/* Ask VFS to verify the permissions. */
memset(&m, '\0', sizeof(message));
m.m_type = VFS_UDS_CHECK_PERMS;
m.VFS_UDS_ENDPT = ep;
m.VFS_UDS_GRANT = grant_id;
m.VFS_UDS_COUNT = UNIX_PATH_MAX;
if ((rc = sendrec(VFS_PROC_NR, &m)) != OK)
panic("error sending to VFS: %d\n", rc);
cpf_revoke(grant_id);
dprintf(("UDS: VFS reply => %d, \"%s\"\n", m.m_type,
addr->sun_path));
return m.m_type; /* reply code: OK, ELOOP, etc. */
}
/*
* Verify whether the given file descriptor is valid for the given process, and
* obtain a filp object identifier upon success.
*/
int
vfs_verify_fd(endpoint_t ep, int fd, filp_id_t *filp)
{
int rc;
message m;
dprintf(("UDS: vfs_verify_fd(%d, %d)\n", ep, fd));
memset(&m, '\0', sizeof(message));
m.m_type = VFS_UDS_VERIFY_FD;
m.VFS_UDS_ENDPT = ep;
m.VFS_UDS_FD = fd;
if ((rc = sendrec(VFS_PROC_NR, &m)) != OK)
panic("error sending to VFS: %d\n", rc);
dprintf(("UDS: VFS reply => %d, %p\n", m.m_type, m.VFS_UDS_FILP));
if (m.m_type != OK)
return m.m_type;
*filp = m.VFS_UDS_FILP;
return OK;
}
/*
* Mark a filp object as in flight, that is, in use by UDS.
*/
int
vfs_set_filp(filp_id_t sfilp)
{
int rc;
message m;
dprintf(("UDS: set_filp(%p)\n", sfilp));
memset(&m, '\0', sizeof(message));
m.m_type = VFS_UDS_SET_FILP;
m.VFS_UDS_FILP = sfilp;
if ((rc = sendrec(VFS_PROC_NR, &m)) != OK)
panic("error sending to VFS: %d\n", rc);
dprintf(("UDS: VFS reply => %d\n", m.m_type));
return m.m_type; /* reply code: OK, ELOOP, etc. */
}
/*
* Copy a filp object into a process, yielding a file descriptor.
*/
int
vfs_copy_filp(endpoint_t to_ep, filp_id_t cfilp)
{
int rc;
message m;
dprintf(("UDS: vfs_copy_filp(%d, %p)\n", to_ep, cfilp));
memset(&m, '\0', sizeof(message));
m.m_type = VFS_UDS_COPY_FILP;
m.VFS_UDS_ENDPT = to_ep;
m.VFS_UDS_FILP = cfilp;
if ((rc = sendrec(VFS_PROC_NR, &m)) != OK)
panic("error sending to VFS: %d\n", rc);
dprintf(("UDS: VFS reply => %d\n", m.m_type));
return m.m_type;
}
/*
* Mark a filp object as no longer in flight.
*/
int
vfs_put_filp(filp_id_t pfilp)
{
int rc;
message m;
dprintf(("UDS: vfs_put_filp(%p)\n", pfilp));
memset(&m, '\0', sizeof(message));
m.m_type = VFS_UDS_PUT_FILP;
m.VFS_UDS_FILP = pfilp;
if ((rc = sendrec(VFS_PROC_NR, &m)) != OK)
panic("error sending to VFS: %d\n", rc);
dprintf(("UDS: VFS reply => %d\n", m.m_type));
return m.m_type; /* reply code: OK, ELOOP, etc. */
}
/*
* Undo creation of a file descriptor in a process.
*/
int
vfs_cancel_fd(endpoint_t ep, int fd)
{
int rc;
message m;
dprintf(("UDS: vfs_cancel_fd(%d,%d)\n", ep, fd));
memset(&m, '\0', sizeof(message));
m.m_type = VFS_UDS_CANCEL_FD;
m.VFS_UDS_ENDPT = ep;
m.VFS_UDS_FD = fd;
if ((rc = sendrec(VFS_PROC_NR, &m)) != OK)
panic("error sending to VFS: %d\n", rc);
dprintf(("UDS: VFS reply => %d\n", m.m_type));
return m.m_type; /* reply code: OK, ELOOP, etc. */
}