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a520047095
freebsd-dev/sys/netgraph/ng_ksocket.c
Robert Watson 2658b3bb8e Integrate accept locking from rwatson_netperf, introducing a new 
global mutex, accept_mtx, which serializes access to the following
fields across all sockets:

          so_qlen          so_incqlen         so_qstate
          so_comp          so_incomp          so_list
          so_head

While providing only coarse granularity, this approach avoids lock
order issues between sockets by avoiding ownership of the fields
by a specific socket and its per-socket mutexes.

While here, rewrite soclose(), sofree(), soaccept(), and
sonewconn() to add assertions, close additional races and  address
lock order concerns.  In particular:

- Reorganize the optimistic concurrency behavior in accept1() to
  always allocate a file descriptor with falloc() so that if we do
  find a socket, we don't have to encounter the "Oh, there wasn't
  a socket" race that can occur if falloc() sleeps in the current
  code, which broke inbound accept() ordering, not to mention
  requiring backing out socket state changes in a way that raced
  with the protocol level.  We may want to add a lockless read of
  the queue state if polling of empty queues proves to be important
  to optimize.

- In accept1(), soref() the socket while holding the accept lock
  so that the socket cannot be free'd in a race with the protocol
  layer.  Likewise in netgraph equivilents of the accept1() code.

- In sonewconn(), loop waiting for the queue to be small enough to
  insert our new socket once we've committed to inserting it, or
  races can occur that cause the incomplete socket queue to
  overfill.  In the previously implementation, it was sufficient
  to simply tested once since calling soabort() didn't release
  synchronization permitting another thread to insert a socket as
  we discard a previous one.

- In soclose()/sofree()/et al, it is the responsibility of the
  caller to remove a socket from the incomplete connection queue
  before calling soabort(), which prevents soabort() from having
  to walk into the accept socket to release the socket from its
  queue, and avoids races when releasing the accept mutex to enter
  soabort(), permitting soabort() to avoid lock ordering issues
  with the caller.

- Generally cluster accept queue related operations together
  throughout these functions in order to facilitate locking.

Annotate new locking in socketvar.h.
2004-06-02 04:15:39 +00:00

1297 lines
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/*
* ng_ksocket.c
*
* Copyright (c) 1996-1999 Whistle Communications, Inc.
* All rights reserved.
*
* Subject to the following obligations and disclaimer of warranty, use and
* redistribution of this software, in source or object code forms, with or
* without modifications are expressly permitted by Whistle Communications;
* provided, however, that:
* 1. Any and all reproductions of the source or object code must include the
* copyright notice above and the following disclaimer of warranties; and
* 2. No rights are granted, in any manner or form, to use Whistle
* Communications, Inc. trademarks, including the mark "WHISTLE
* COMMUNICATIONS" on advertising, endorsements, or otherwise except as
* such appears in the above copyright notice or in the software.
*
* THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
* TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
* REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
* INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
* WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
* REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
* SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
* IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
* RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
* WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER 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 WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* Author: Archie Cobbs <archie@freebsd.org>
*
* $FreeBSD$
* $Whistle: ng_ksocket.c,v 1.1 1999/11/16 20:04:40 archie Exp $
*/
/*
* Kernel socket node type. This node type is basically a kernel-mode
* version of a socket... kindof like the reverse of the socket node type.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/ctype.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_ksocket.h>
#include <netinet/in.h>
#include <netatalk/at.h>
#ifdef NG_SEPARATE_MALLOC
MALLOC_DEFINE(M_NETGRAPH_KSOCKET, "netgraph_ksock", "netgraph ksock node ");
#else
#define M_NETGRAPH_KSOCKET M_NETGRAPH
#endif
#define OFFSETOF(s, e) ((char *)&((s *)0)->e - (char *)((s *)0))
#define SADATA_OFFSET (OFFSETOF(struct sockaddr, sa_data))
/* Node private data */
struct ng_ksocket_private {
node_p node;
hook_p hook;
struct socket *so;
LIST_HEAD(, ng_ksocket_private) embryos;
LIST_ENTRY(ng_ksocket_private) siblings;
u_int32_t flags;
u_int32_t response_token;
ng_ID_t response_addr;
};
typedef struct ng_ksocket_private *priv_p;
/* Flags for priv_p */
#define KSF_CONNECTING 0x00000001 /* Waiting for connection complete */
#define KSF_ACCEPTING 0x00000002 /* Waiting for accept complete */
#define KSF_EOFSEEN 0x00000004 /* Have sent 0-length EOF mbuf */
#define KSF_CLONED 0x00000008 /* Cloned from an accepting socket */
#define KSF_EMBRYONIC 0x00000010 /* Cloned node with no hooks yet */
#define KSF_SENDING 0x00000020 /* Sending on socket */
/* Netgraph node methods */
static ng_constructor_t ng_ksocket_constructor;
static ng_rcvmsg_t ng_ksocket_rcvmsg;
static ng_shutdown_t ng_ksocket_shutdown;
static ng_newhook_t ng_ksocket_newhook;
static ng_rcvdata_t ng_ksocket_rcvdata;
static ng_connect_t ng_ksocket_connect;
static ng_disconnect_t ng_ksocket_disconnect;
/* Alias structure */
struct ng_ksocket_alias {
const char *name;
const int value;
const int family;
};
/* Protocol family aliases */
static const struct ng_ksocket_alias ng_ksocket_families[] = {
{ "local", PF_LOCAL },
{ "inet", PF_INET },
{ "inet6", PF_INET6 },
{ "atalk", PF_APPLETALK },
{ "ipx", PF_IPX },
{ "atm", PF_ATM },
{ NULL, -1 },
};
/* Socket type aliases */
static const struct ng_ksocket_alias ng_ksocket_types[] = {
{ "stream", SOCK_STREAM },
{ "dgram", SOCK_DGRAM },
{ "raw", SOCK_RAW },
{ "rdm", SOCK_RDM },
{ "seqpacket", SOCK_SEQPACKET },
{ NULL, -1 },
};
/* Protocol aliases */
static const struct ng_ksocket_alias ng_ksocket_protos[] = {
{ "ip", IPPROTO_IP, PF_INET },
{ "raw", IPPROTO_RAW, PF_INET },
{ "icmp", IPPROTO_ICMP, PF_INET },
{ "igmp", IPPROTO_IGMP, PF_INET },
{ "tcp", IPPROTO_TCP, PF_INET },
{ "udp", IPPROTO_UDP, PF_INET },
{ "gre", IPPROTO_GRE, PF_INET },
{ "esp", IPPROTO_ESP, PF_INET },
{ "ah", IPPROTO_AH, PF_INET },
{ "swipe", IPPROTO_SWIPE, PF_INET },
{ "encap", IPPROTO_ENCAP, PF_INET },
{ "divert", IPPROTO_DIVERT, PF_INET },
{ "pim", IPPROTO_PIM, PF_INET },
{ "ddp", ATPROTO_DDP, PF_APPLETALK },
{ "aarp", ATPROTO_AARP, PF_APPLETALK },
{ NULL, -1 },
};
/* Helper functions */
static int ng_ksocket_check_accept(priv_p);
static void ng_ksocket_finish_accept(priv_p);
static void ng_ksocket_incoming(struct socket *so, void *arg, int waitflag);
static int ng_ksocket_parse(const struct ng_ksocket_alias *aliases,
const char *s, int family);
static void ng_ksocket_incoming2(node_p node, hook_p hook,
void *arg1, int waitflag);
/************************************************************************
STRUCT SOCKADDR PARSE TYPE
************************************************************************/
/* Get the length of the data portion of a generic struct sockaddr */
static int
ng_parse_generic_sockdata_getLength(const struct ng_parse_type *type,
const u_char *start, const u_char *buf)
{
const struct sockaddr *sa;
sa = (const struct sockaddr *)(buf - SADATA_OFFSET);
return (sa->sa_len < SADATA_OFFSET) ? 0 : sa->sa_len - SADATA_OFFSET;
}
/* Type for the variable length data portion of a generic struct sockaddr */
static const struct ng_parse_type ng_ksocket_generic_sockdata_type = {
&ng_parse_bytearray_type,
&ng_parse_generic_sockdata_getLength
};
/* Type for a generic struct sockaddr */
static const struct ng_parse_struct_field
ng_parse_generic_sockaddr_type_fields[] = {
{ "len", &ng_parse_uint8_type },
{ "family", &ng_parse_uint8_type },
{ "data", &ng_ksocket_generic_sockdata_type },
{ NULL }
};
static const struct ng_parse_type ng_ksocket_generic_sockaddr_type = {
&ng_parse_struct_type,
&ng_parse_generic_sockaddr_type_fields
};
/* Convert a struct sockaddr from ASCII to binary. If its a protocol
family that we specially handle, do that, otherwise defer to the
generic parse type ng_ksocket_generic_sockaddr_type. */
static int
ng_ksocket_sockaddr_parse(const struct ng_parse_type *type,
const char *s, int *off, const u_char *const start,
u_char *const buf, int *buflen)
{
struct sockaddr *const sa = (struct sockaddr *)buf;
enum ng_parse_token tok;
char fambuf[32];
int family, len;
char *t;
/* If next token is a left curly brace, use generic parse type */
if ((tok = ng_parse_get_token(s, off, &len)) == T_LBRACE) {
return (*ng_ksocket_generic_sockaddr_type.supertype->parse)
(&ng_ksocket_generic_sockaddr_type,
s, off, start, buf, buflen);
}
/* Get socket address family followed by a slash */
while (isspace(s[*off]))
(*off)++;
if ((t = index(s + *off, '/')) == NULL)
return (EINVAL);
if ((len = t - (s + *off)) > sizeof(fambuf) - 1)
return (EINVAL);
strncpy(fambuf, s + *off, len);
fambuf[len] = '\0';
*off += len + 1;
if ((family = ng_ksocket_parse(ng_ksocket_families, fambuf, 0)) == -1)
return (EINVAL);
/* Set family */
if (*buflen < SADATA_OFFSET)
return (ERANGE);
sa->sa_family = family;
/* Set family-specific data and length */
switch (sa->sa_family) {
case PF_LOCAL: /* Get pathname */
{
const int pathoff = OFFSETOF(struct sockaddr_un, sun_path);
struct sockaddr_un *const sun = (struct sockaddr_un *)sa;
int toklen, pathlen;
char *path;
if ((path = ng_get_string_token(s, off, &toklen, NULL)) == NULL)
return (EINVAL);
pathlen = strlen(path);
if (pathlen > SOCK_MAXADDRLEN) {
FREE(path, M_NETGRAPH_KSOCKET);
return (E2BIG);
}
if (*buflen < pathoff + pathlen) {
FREE(path, M_NETGRAPH_KSOCKET);
return (ERANGE);
}
*off += toklen;
bcopy(path, sun->sun_path, pathlen);
sun->sun_len = pathoff + pathlen;
FREE(path, M_NETGRAPH_KSOCKET);
break;
}
case PF_INET: /* Get an IP address with optional port */
{
struct sockaddr_in *const sin = (struct sockaddr_in *)sa;
int i;
/* Parse this: <ipaddress>[:port] */
for (i = 0; i < 4; i++) {
u_long val;
char *eptr;
val = strtoul(s + *off, &eptr, 10);
if (val > 0xff || eptr == s + *off)
return (EINVAL);
*off += (eptr - (s + *off));
((u_char *)&sin->sin_addr)[i] = (u_char)val;
if (i < 3) {
if (s[*off] != '.')
return (EINVAL);
(*off)++;
} else if (s[*off] == ':') {
(*off)++;
val = strtoul(s + *off, &eptr, 10);
if (val > 0xffff || eptr == s + *off)
return (EINVAL);
*off += (eptr - (s + *off));
sin->sin_port = htons(val);
} else
sin->sin_port = 0;
}
bzero(&sin->sin_zero, sizeof(sin->sin_zero));
sin->sin_len = sizeof(*sin);
break;
}
#if 0
case PF_APPLETALK: /* XXX implement these someday */
case PF_INET6:
case PF_IPX:
#endif
default:
return (EINVAL);
}
/* Done */
*buflen = sa->sa_len;
return (0);
}
/* Convert a struct sockaddr from binary to ASCII */
static int
ng_ksocket_sockaddr_unparse(const struct ng_parse_type *type,
const u_char *data, int *off, char *cbuf, int cbuflen)
{
const struct sockaddr *sa = (const struct sockaddr *)(data + *off);
int slen = 0;
/* Output socket address, either in special or generic format */
switch (sa->sa_family) {
case PF_LOCAL:
{
const int pathoff = OFFSETOF(struct sockaddr_un, sun_path);
const struct sockaddr_un *sun = (const struct sockaddr_un *)sa;
const int pathlen = sun->sun_len - pathoff;
char pathbuf[SOCK_MAXADDRLEN + 1];
char *pathtoken;
bcopy(sun->sun_path, pathbuf, pathlen);
if ((pathtoken = ng_encode_string(pathbuf, pathlen)) == NULL)
return (ENOMEM);
slen += snprintf(cbuf, cbuflen, "local/%s", pathtoken);
FREE(pathtoken, M_NETGRAPH_KSOCKET);
if (slen >= cbuflen)
return (ERANGE);
*off += sun->sun_len;
return (0);
}
case PF_INET:
{
const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
slen += snprintf(cbuf, cbuflen, "inet/%d.%d.%d.%d",
((const u_char *)&sin->sin_addr)[0],
((const u_char *)&sin->sin_addr)[1],
((const u_char *)&sin->sin_addr)[2],
((const u_char *)&sin->sin_addr)[3]);
if (sin->sin_port != 0) {
slen += snprintf(cbuf + strlen(cbuf),
cbuflen - strlen(cbuf), ":%d",
(u_int)ntohs(sin->sin_port));
}
if (slen >= cbuflen)
return (ERANGE);
*off += sizeof(*sin);
return(0);
}
#if 0
case PF_APPLETALK: /* XXX implement these someday */
case PF_INET6:
case PF_IPX:
#endif
default:
return (*ng_ksocket_generic_sockaddr_type.supertype->unparse)
(&ng_ksocket_generic_sockaddr_type,
data, off, cbuf, cbuflen);
}
}
/* Parse type for struct sockaddr */
static const struct ng_parse_type ng_ksocket_sockaddr_type = {
NULL,
NULL,
NULL,
&ng_ksocket_sockaddr_parse,
&ng_ksocket_sockaddr_unparse,
NULL /* no such thing as a default struct sockaddr */
};
/************************************************************************
STRUCT NG_KSOCKET_SOCKOPT PARSE TYPE
************************************************************************/
/* Get length of the struct ng_ksocket_sockopt value field, which is the
just the excess of the message argument portion over the length of
the struct ng_ksocket_sockopt. */
static int
ng_parse_sockoptval_getLength(const struct ng_parse_type *type,
const u_char *start, const u_char *buf)
{
static const int offset = OFFSETOF(struct ng_ksocket_sockopt, value);
const struct ng_ksocket_sockopt *sopt;
const struct ng_mesg *msg;
sopt = (const struct ng_ksocket_sockopt *)(buf - offset);
msg = (const struct ng_mesg *)((const u_char *)sopt - sizeof(*msg));
return msg->header.arglen - sizeof(*sopt);
}
/* Parse type for the option value part of a struct ng_ksocket_sockopt
XXX Eventually, we should handle the different socket options specially.
XXX This would avoid byte order problems, eg an integer value of 1 is
XXX going to be "[1]" for little endian or "[3=1]" for big endian. */
static const struct ng_parse_type ng_ksocket_sockoptval_type = {
&ng_parse_bytearray_type,
&ng_parse_sockoptval_getLength
};
/* Parse type for struct ng_ksocket_sockopt */
static const struct ng_parse_struct_field ng_ksocket_sockopt_type_fields[]
= NG_KSOCKET_SOCKOPT_INFO(&ng_ksocket_sockoptval_type);
static const struct ng_parse_type ng_ksocket_sockopt_type = {
&ng_parse_struct_type,
&ng_ksocket_sockopt_type_fields
};
/* Parse type for struct ng_ksocket_accept */
static const struct ng_parse_struct_field ng_ksocket_accept_type_fields[]
= NGM_KSOCKET_ACCEPT_INFO;
static const struct ng_parse_type ng_ksocket_accept_type = {
&ng_parse_struct_type,
&ng_ksocket_accept_type_fields
};
/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_ksocket_cmds[] = {
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_BIND,
"bind",
&ng_ksocket_sockaddr_type,
NULL
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_LISTEN,
"listen",
&ng_parse_int32_type,
NULL
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_ACCEPT,
"accept",
NULL,
&ng_ksocket_accept_type
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_CONNECT,
"connect",
&ng_ksocket_sockaddr_type,
&ng_parse_int32_type
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_GETNAME,
"getname",
NULL,
&ng_ksocket_sockaddr_type
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_GETPEERNAME,
"getpeername",
NULL,
&ng_ksocket_sockaddr_type
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_SETOPT,
"setopt",
&ng_ksocket_sockopt_type,
NULL
},
{
NGM_KSOCKET_COOKIE,
NGM_KSOCKET_GETOPT,
"getopt",
&ng_ksocket_sockopt_type,
&ng_ksocket_sockopt_type
},
{ 0 }
};
/* Node type descriptor */
static struct ng_type ng_ksocket_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_KSOCKET_NODE_TYPE,
.constructor = ng_ksocket_constructor,
.rcvmsg = ng_ksocket_rcvmsg,
.shutdown = ng_ksocket_shutdown,
.newhook = ng_ksocket_newhook,
.connect = ng_ksocket_connect,
.rcvdata = ng_ksocket_rcvdata,
.disconnect = ng_ksocket_disconnect,
.cmdlist = ng_ksocket_cmds,
};
NETGRAPH_INIT(ksocket, &ng_ksocket_typestruct);
#define ERROUT(x) do { error = (x); goto done; } while (0)
/************************************************************************
NETGRAPH NODE STUFF
************************************************************************/
/*
* Node type constructor
* The NODE part is assumed to be all set up.
* There is already a reference to the node for us.
*/
static int
ng_ksocket_constructor(node_p node)
{
priv_p priv;
/* Allocate private structure */
MALLOC(priv, priv_p, sizeof(*priv),
M_NETGRAPH_KSOCKET, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
LIST_INIT(&priv->embryos);
/* cross link them */
priv->node = node;
NG_NODE_SET_PRIVATE(node, priv);
/* Done */
return (0);
}
/*
* Give our OK for a hook to be added. The hook name is of the
* form "<family>/<type>/<proto>" where the three components may
* be decimal numbers or else aliases from the above lists.
*
* Connecting a hook amounts to opening the socket. Disconnecting
* the hook closes the socket and destroys the node as well.
*/
static int
ng_ksocket_newhook(node_p node, hook_p hook, const char *name0)
{
struct thread *td = curthread ? curthread : &thread0; /* XXX broken */
const priv_p priv = NG_NODE_PRIVATE(node);
char *s1, *s2, name[NG_HOOKSIZ];
int family, type, protocol, error;
/* Check if we're already connected */
if (priv->hook != NULL)
return (EISCONN);
if (priv->flags & KSF_CLONED) {
if (priv->flags & KSF_EMBRYONIC) {
/* Remove ourselves from our parent's embryo list */
LIST_REMOVE(priv, siblings);
priv->flags &= ~KSF_EMBRYONIC;
}
} else {
/* Extract family, type, and protocol from hook name */
snprintf(name, sizeof(name), "%s", name0);
s1 = name;
if ((s2 = index(s1, '/')) == NULL)
return (EINVAL);
*s2++ = '\0';
family = ng_ksocket_parse(ng_ksocket_families, s1, 0);
if (family == -1)
return (EINVAL);
s1 = s2;
if ((s2 = index(s1, '/')) == NULL)
return (EINVAL);
*s2++ = '\0';
type = ng_ksocket_parse(ng_ksocket_types, s1, 0);
if (type == -1)
return (EINVAL);
s1 = s2;
protocol = ng_ksocket_parse(ng_ksocket_protos, s1, family);
if (protocol == -1)
return (EINVAL);
/* Create the socket */
error = socreate(family, &priv->so, type, protocol,
td->td_ucred, td);
if (error != 0)
return (error);
/* XXX call soreserve() ? */
}
/* OK */
priv->hook = hook;
return(0);
}
static int
ng_ksocket_connect(hook_p hook)
{
node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
struct socket *const so = priv->so;
/* Add our hook for incoming data and other events */
priv->so->so_upcallarg = (caddr_t)node;
priv->so->so_upcall = ng_ksocket_incoming;
priv->so->so_rcv.sb_flags |= SB_UPCALL;
priv->so->so_snd.sb_flags |= SB_UPCALL;
priv->so->so_state |= SS_NBIO;
/*
* --Original comment--
* On a cloned socket we may have already received one or more
* upcalls which we couldn't handle without a hook. Handle
* those now.
* We cannot call the upcall function directly
* from here, because until this function has returned our
* hook isn't connected.
*
* ---meta comment for -current ---
* XXX This is dubius.
* Upcalls between the time that the hook was
* first created and now (on another processesor) will
* be earlier on the queue than the request to finalise the hook.
* By the time the hook is finalised,
* The queued upcalls will have happenned and the code
* will have discarded them because of a lack of a hook.
* (socket not open).
*
* This is a bad byproduct of the complicated way in which hooks
* are now created (3 daisy chained async events).
*
* Since we are a netgraph operation
* We know that we hold a lock on this node. This forces the
* request we make below to be queued rather than implemented
* immediatly which will cause the upcall function to be called a bit
* later.
* However, as we will run any waiting queued operations immediatly
* after doing this one, if we have not finalised the other end
* of the hook, those queued operations will fail.
*/
if (priv->flags & KSF_CLONED) {
ng_send_fn(node, NULL, &ng_ksocket_incoming2, so, M_NOWAIT);
}
return (0);
}
/*
* Receive a control message
*/
static int
ng_ksocket_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
struct thread *td = curthread ? curthread : &thread0; /* XXX broken */
const priv_p priv = NG_NODE_PRIVATE(node);
struct socket *const so = priv->so;
struct ng_mesg *resp = NULL;
int error = 0;
struct ng_mesg *msg;
ng_ID_t raddr;
NGI_GET_MSG(item, msg);
switch (msg->header.typecookie) {
case NGM_KSOCKET_COOKIE:
switch (msg->header.cmd) {
case NGM_KSOCKET_BIND:
{
struct sockaddr *const sa
= (struct sockaddr *)msg->data;
/* Sanity check */
if (msg->header.arglen < SADATA_OFFSET
|| msg->header.arglen < sa->sa_len)
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Bind */
error = sobind(so, sa, td);
break;
}
case NGM_KSOCKET_LISTEN:
{
/* Sanity check */
if (msg->header.arglen != sizeof(int32_t))
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Listen */
error = solisten(so, *((int32_t *)msg->data), td);
break;
}
case NGM_KSOCKET_ACCEPT:
{
/* Sanity check */
if (msg->header.arglen != 0)
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Make sure the socket is capable of accepting */
if (!(so->so_options & SO_ACCEPTCONN))
ERROUT(EINVAL);
if (priv->flags & KSF_ACCEPTING)
ERROUT(EALREADY);
error = ng_ksocket_check_accept(priv);
if (error != 0 && error != EWOULDBLOCK)
ERROUT(error);
/*
* If a connection is already complete, take it.
* Otherwise let the upcall function deal with
* the connection when it comes in.
*/
priv->response_token = msg->header.token;
raddr = priv->response_addr = NGI_RETADDR(item);
if (error == 0) {
ng_ksocket_finish_accept(priv);
} else
priv->flags |= KSF_ACCEPTING;
break;
}
case NGM_KSOCKET_CONNECT:
{
struct sockaddr *const sa
= (struct sockaddr *)msg->data;
/* Sanity check */
if (msg->header.arglen < SADATA_OFFSET
|| msg->header.arglen < sa->sa_len)
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Do connect */
if ((so->so_state & SS_ISCONNECTING) != 0)
ERROUT(EALREADY);
if ((error = soconnect(so, sa, td)) != 0) {
so->so_state &= ~SS_ISCONNECTING;
ERROUT(error);
}
if ((so->so_state & SS_ISCONNECTING) != 0) {
/* We will notify the sender when we connect */
priv->response_token = msg->header.token;
raddr = priv->response_addr = NGI_RETADDR(item);
priv->flags |= KSF_CONNECTING;
ERROUT(EINPROGRESS);
}
break;
}
case NGM_KSOCKET_GETNAME:
case NGM_KSOCKET_GETPEERNAME:
{
int (*func)(struct socket *so, struct sockaddr **nam);
struct sockaddr *sa = NULL;
int len;
/* Sanity check */
if (msg->header.arglen != 0)
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Get function */
if (msg->header.cmd == NGM_KSOCKET_GETPEERNAME) {
if ((so->so_state
& (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0)
ERROUT(ENOTCONN);
func = so->so_proto->pr_usrreqs->pru_peeraddr;
} else
func = so->so_proto->pr_usrreqs->pru_sockaddr;
/* Get local or peer address */
if ((error = (*func)(so, &sa)) != 0)
goto bail;
len = (sa == NULL) ? 0 : sa->sa_len;
/* Send it back in a response */
NG_MKRESPONSE(resp, msg, len, M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
goto bail;
}
bcopy(sa, resp->data, len);
bail:
/* Cleanup */
if (sa != NULL)
FREE(sa, M_SONAME);
break;
}
case NGM_KSOCKET_GETOPT:
{
struct ng_ksocket_sockopt *ksopt =
(struct ng_ksocket_sockopt *)msg->data;
struct sockopt sopt;
/* Sanity check */
if (msg->header.arglen != sizeof(*ksopt))
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Get response with room for option value */
NG_MKRESPONSE(resp, msg, sizeof(*ksopt)
+ NG_KSOCKET_MAX_OPTLEN, M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
/* Get socket option, and put value in the response */
sopt.sopt_dir = SOPT_GET;
sopt.sopt_level = ksopt->level;
sopt.sopt_name = ksopt->name;
sopt.sopt_td = NULL;
sopt.sopt_valsize = NG_KSOCKET_MAX_OPTLEN;
ksopt = (struct ng_ksocket_sockopt *)resp->data;
sopt.sopt_val = ksopt->value;
if ((error = sogetopt(so, &sopt)) != 0) {
NG_FREE_MSG(resp);
break;
}
/* Set actual value length */
resp->header.arglen = sizeof(*ksopt)
+ sopt.sopt_valsize;
break;
}
case NGM_KSOCKET_SETOPT:
{
struct ng_ksocket_sockopt *const ksopt =
(struct ng_ksocket_sockopt *)msg->data;
const int valsize = msg->header.arglen - sizeof(*ksopt);
struct sockopt sopt;
/* Sanity check */
if (valsize < 0)
ERROUT(EINVAL);
if (so == NULL)
ERROUT(ENXIO);
/* Set socket option */
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = ksopt->level;
sopt.sopt_name = ksopt->name;
sopt.sopt_val = ksopt->value;
sopt.sopt_valsize = valsize;
sopt.sopt_td = NULL;
error = sosetopt(so, &sopt);
break;
}
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive incoming data on our hook. Send it out the socket.
*/
static int
ng_ksocket_rcvdata(hook_p hook, item_p item)
{
struct thread *td = curthread ? curthread : &thread0; /* XXX broken */
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
struct socket *const so = priv->so;
struct sockaddr *sa = NULL;
meta_p meta;
int error;
struct mbuf *m;
/* Avoid reentrantly sending on the socket */
if ((priv->flags & KSF_SENDING) != 0) {
NG_FREE_ITEM(item);
return (EDEADLK);
}
/* Extract data and meta information */
NGI_GET_M(item, m);
NGI_GET_META(item, meta);
NG_FREE_ITEM(item);
/* If any meta info, look for peer socket address */
if (meta != NULL) {
struct meta_field_header *field;
/* Look for peer socket address */
for (field = &meta->options[0];
(caddr_t)field < (caddr_t)meta + meta->used_len;
field = (struct meta_field_header *)
((caddr_t)field + field->len)) {
if (field->cookie != NGM_KSOCKET_COOKIE
|| field->type != NG_KSOCKET_META_SOCKADDR)
continue;
sa = (struct sockaddr *)field->data;
break;
}
}
/* Send packet */
priv->flags |= KSF_SENDING;
error = (*so->so_proto->pr_usrreqs->pru_sosend)(so, sa, 0, m, 0, 0, td);
priv->flags &= ~KSF_SENDING;
/* Clean up and exit */
NG_FREE_META(meta);
return (error);
}
/*
* Destroy node
*/
static int
ng_ksocket_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
priv_p embryo;
/* Close our socket (if any) */
if (priv->so != NULL) {
priv->so->so_upcall = NULL;
priv->so->so_rcv.sb_flags &= ~SB_UPCALL;
priv->so->so_snd.sb_flags &= ~SB_UPCALL;
soclose(priv->so);
priv->so = NULL;
}
/* If we are an embryo, take ourselves out of the parent's list */
if (priv->flags & KSF_EMBRYONIC) {
LIST_REMOVE(priv, siblings);
priv->flags &= ~KSF_EMBRYONIC;
}
/* Remove any embryonic children we have */
while (!LIST_EMPTY(&priv->embryos)) {
embryo = LIST_FIRST(&priv->embryos);
ng_rmnode_self(embryo->node);
}
/* Take down netgraph node */
bzero(priv, sizeof(*priv));
FREE(priv, M_NETGRAPH_KSOCKET);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node); /* let the node escape */
return (0);
}
/*
* Hook disconnection
*/
static int
ng_ksocket_disconnect(hook_p hook)
{
KASSERT(NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0,
("%s: numhooks=%d?", __func__,
NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook))));
if (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
ng_rmnode_self(NG_HOOK_NODE(hook));
return (0);
}
/************************************************************************
HELPER STUFF
************************************************************************/
/*
* You should no-longer "just call" a netgraph node function
* from an external asynchronous event.
* This is because in doing so you are ignoring the locking on the netgraph
* nodes. Instead call your function via
* "int ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn,
* void *arg1, int arg2);"
* this will call the function you chose, but will first do all the
* locking rigmarole. Your function MAY only be called at some distant future
* time (several millisecs away) so don't give it any arguments
* that may be revoked soon (e.g. on your stack).
* In this case even the 'so' argument is doubtful.
* While the function request is being processed the node
* has an extra reference and as such will not disappear until
* the request has at least been done, but the 'so' may not be so lucky.
* handle this by checking the validity of the node in the target function
* before dereferencing the socket pointer.
*/
static void
ng_ksocket_incoming(struct socket *so, void *arg, int waitflag)
{
const node_p node = arg;
ng_send_fn(node, NULL, &ng_ksocket_incoming2, so, waitflag);
}
/*
* When incoming data is appended to the socket, we get notified here.
* This is also called whenever a significant event occurs for the socket.
* We know that HOOK is NULL. Because of how we were called we know we have a
* lock on this node an are participating inthe netgraph locking.
* Our original caller may have queued this even some time ago and
* we cannot trust that he even still exists. The node however is being
* held with a reference by the queueing code, at least until we finish,
* even if it has been zapped, so first check it's validiy
* before we trust the socket (which was derived from it).
*/
static void
ng_ksocket_incoming2(node_p node, hook_p hook, void *arg1, int waitflag)
{
struct socket *so = arg1;
const priv_p priv = NG_NODE_PRIVATE(node);
struct mbuf *m;
struct ng_mesg *response;
struct uio auio;
int s, flags, error;
s = splnet();
/* Sanity check */
if (NG_NODE_NOT_VALID(node)) {
splx(s);
return;
}
/* so = priv->so; *//* XXX could have derived this like so */
KASSERT(so == priv->so, ("%s: wrong socket", __func__));
/* Check whether a pending connect operation has completed */
if (priv->flags & KSF_CONNECTING) {
if ((error = so->so_error) != 0) {
so->so_error = 0;
so->so_state &= ~SS_ISCONNECTING;
}
if (!(so->so_state & SS_ISCONNECTING)) {
NG_MKMESSAGE(response, NGM_KSOCKET_COOKIE,
NGM_KSOCKET_CONNECT, sizeof(int32_t), waitflag);
if (response != NULL) {
response->header.flags |= NGF_RESP;
response->header.token = priv->response_token;
*(int32_t *)response->data = error;
/*
* send an async "response" message
* to the node that set us up
* (if it still exists)
*/
NG_SEND_MSG_ID(error, node,
response, priv->response_addr, 0);
}
priv->flags &= ~KSF_CONNECTING;
}
}
/* Check whether a pending accept operation has completed */
if (priv->flags & KSF_ACCEPTING) {
error = ng_ksocket_check_accept(priv);
if (error != EWOULDBLOCK)
priv->flags &= ~KSF_ACCEPTING;
if (error == 0)
ng_ksocket_finish_accept(priv);
}
/*
* If we don't have a hook, we must handle data events later. When
* the hook gets created and is connected, this upcall function
* will be called again.
*/
if (priv->hook == NULL) {
splx(s);
return;
}
/* Read and forward available mbuf's */
auio.uio_td = NULL;
auio.uio_resid = 1000000000;
flags = MSG_DONTWAIT;
while (1) {
struct sockaddr *sa = NULL;
meta_p meta = NULL;
struct mbuf *n;
/* Try to get next packet from socket */
if ((error = (*so->so_proto->pr_usrreqs->pru_soreceive)
(so, (so->so_state & SS_ISCONNECTED) ? NULL : &sa,
&auio, &m, (struct mbuf **)0, &flags)) != 0)
break;
/* See if we got anything */
if (m == NULL) {
if (sa != NULL)
FREE(sa, M_SONAME);
break;
}
/* Don't trust the various socket layers to get the
packet header and length correct (eg. kern/15175) */
for (n = m, m->m_pkthdr.len = 0; n != NULL; n = n->m_next)
m->m_pkthdr.len += n->m_len;
/* Put peer's socket address (if any) into a meta info blob */
if (sa != NULL) {
struct meta_field_header *mhead;
u_int len;
len = sizeof(*meta) + sizeof(*mhead) + sa->sa_len;
MALLOC(meta, meta_p, len, M_NETGRAPH_META,
M_NOWAIT | M_ZERO);
if (meta == NULL) {
FREE(sa, M_SONAME);
goto sendit;
}
mhead = &meta->options[0];
meta->allocated_len = len;
meta->used_len = len;
mhead->cookie = NGM_KSOCKET_COOKIE;
mhead->type = NG_KSOCKET_META_SOCKADDR;
mhead->len = sizeof(*mhead) + sa->sa_len;
bcopy(sa, mhead->data, sa->sa_len);
FREE(sa, M_SONAME);
}
sendit: /* Forward data with optional peer sockaddr as meta info */
NG_SEND_DATA(error, priv->hook, m, meta);
}
/*
* If the peer has closed the connection, forward a 0-length mbuf
* to indicate end-of-file.
*/
if (so->so_state & SS_CANTRCVMORE && !(priv->flags & KSF_EOFSEEN)) {
MGETHDR(m, waitflag, MT_DATA);
if (m != NULL) {
m->m_len = m->m_pkthdr.len = 0;
NG_SEND_DATA_ONLY(error, priv->hook, m);
}
priv->flags |= KSF_EOFSEEN;
}
splx(s);
}
/*
* Check for a completed incoming connection and return 0 if one is found.
* Otherwise return the appropriate error code.
*/
static int
ng_ksocket_check_accept(priv_p priv)
{
struct socket *const head = priv->so;
int error;
if ((error = head->so_error) != 0) {
head->so_error = 0;
return error;
}
/* Unlocked read. */
if (TAILQ_EMPTY(&head->so_comp)) {
if (head->so_state & SS_CANTRCVMORE)
return ECONNABORTED;
return EWOULDBLOCK;
}
return 0;
}
/*
* Handle the first completed incoming connection, assumed to be already
* on the socket's so_comp queue.
*/
static void
ng_ksocket_finish_accept(priv_p priv)
{
struct socket *const head = priv->so;
struct socket *so;
struct sockaddr *sa = NULL;
struct ng_mesg *resp;
struct ng_ksocket_accept *resp_data;
node_p node;
priv_p priv2;
int len;
int error;
ACCEPT_LOCK();
so = TAILQ_FIRST(&head->so_comp);
if (so == NULL) { /* Should never happen */
ACCEPT_UNLOCK();
return;
}
TAILQ_REMOVE(&head->so_comp, so, so_list);
head->so_qlen--;
so->so_qstate &= ~SQ_COMP;
so->so_head = NULL;
soref(so);
so->so_state |= SS_NBIO;
ACCEPT_UNLOCK();
/* XXX KNOTE(&head->so_rcv.sb_sel.si_note, 0); */
soaccept(so, &sa);
len = OFFSETOF(struct ng_ksocket_accept, addr);
if (sa != NULL)
len += sa->sa_len;
NG_MKMESSAGE(resp, NGM_KSOCKET_COOKIE, NGM_KSOCKET_ACCEPT, len,
M_NOWAIT);
if (resp == NULL) {
soclose(so);
goto out;
}
resp->header.flags |= NGF_RESP;
resp->header.token = priv->response_token;
/* Clone a ksocket node to wrap the new socket */
error = ng_make_node_common(&ng_ksocket_typestruct, &node);
if (error) {
FREE(resp, M_NETGRAPH);
soclose(so);
goto out;
}
if (ng_ksocket_constructor(node) != 0) {
NG_NODE_UNREF(node);
FREE(resp, M_NETGRAPH);
soclose(so);
goto out;
}
priv2 = NG_NODE_PRIVATE(node);
priv2->so = so;
priv2->flags |= KSF_CLONED | KSF_EMBRYONIC;
/*
* Insert the cloned node into a list of embryonic children
* on the parent node. When a hook is created on the cloned
* node it will be removed from this list. When the parent
* is destroyed it will destroy any embryonic children it has.
*/
LIST_INSERT_HEAD(&priv->embryos, priv2, siblings);
so->so_upcallarg = (caddr_t)node;
so->so_upcall = ng_ksocket_incoming;
so->so_rcv.sb_flags |= SB_UPCALL;
so->so_snd.sb_flags |= SB_UPCALL;
/* Fill in the response data and send it or return it to the caller */
resp_data = (struct ng_ksocket_accept *)resp->data;
resp_data->nodeid = NG_NODE_ID(node);
if (sa != NULL)
bcopy(sa, &resp_data->addr, sa->sa_len);
NG_SEND_MSG_ID(error, node, resp, priv->response_addr, 0);
out:
if (sa != NULL)
FREE(sa, M_SONAME);
}
/*
* Parse out either an integer value or an alias.
*/
static int
ng_ksocket_parse(const struct ng_ksocket_alias *aliases,
const char *s, int family)
{
int k, val;
char *eptr;
/* Try aliases */
for (k = 0; aliases[k].name != NULL; k++) {
if (strcmp(s, aliases[k].name) == 0
&& aliases[k].family == family)
return aliases[k].value;
}
/* Try parsing as a number */
val = (int)strtoul(s, &eptr, 10);
if (val < 0 || *eptr != '\0')
return (-1);
return (val);
}
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