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b600a98c28
freebsd-dev/sys/netgraph/ng_base.c
archie b600a98c28 Change the prototype of the strto* routines to make the second 
parameter a char ** instead of a const char **.  This make these
kernel routines consistent with the corresponding libc userland
routines.

Which is actually 'correct' is debatable, but consistency and
following the spec was deemed more important in this case.

Reviewed by (in concept):	phk, bde
1999-11-24 01:03:08 +00:00

1652 lines
38 KiB
C
Raw Blame History

/*
* ng_base.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.
*
* Authors: Julian Elischer <julian@whistle.com>
* Archie Cobbs <archie@whistle.com>
*
* $FreeBSD$
* $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
*/
/*
* This file implements the base netgraph code.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/syslog.h>
#include <sys/linker.h>
#include <sys/queue.h>
#include <sys/mbuf.h>
#include <sys/socketvar.h>
#include <sys/ctype.h>
#include <machine/limits.h>
#include <net/netisr.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
/* List of all nodes */
static LIST_HEAD(, ng_node) nodelist;
/* List of installed types */
static LIST_HEAD(, ng_type) typelist;
/* Hash releted definitions */
#define ID_HASH_SIZE 32 /* most systems wont need even this many */
static LIST_HEAD(, ng_node) ID_hash[ID_HASH_SIZE];
/* Don't nead to initialise them because it's a LIST */
/* Internal functions */
static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
static int ng_connect(hook_p hook1, hook_p hook2);
static void ng_disconnect_hook(hook_p hook);
static int ng_generic_msg(node_p here, struct ng_mesg *msg,
const char *retaddr, struct ng_mesg ** resp);
static ng_ID_t ng_decodeidname(const char *name);
static int ngb_mod_event(module_t mod, int event, void *data);
static void ngintr(void);
/* Our own netgraph malloc type */
MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
/* Set this to Debugger("X") to catch all errors as they occur */
#ifndef TRAP_ERROR
#define TRAP_ERROR
#endif
static ng_ID_t nextID = 1;
#ifdef INVARIANTS
#define CHECK_DATA_MBUF(m) do { \
struct mbuf *n; \
int total; \
\
if (((m)->m_flags & M_PKTHDR) == 0) \
panic("%s: !PKTHDR", __FUNCTION__); \
for (total = 0, n = (m); n != NULL; n = n->m_next) \
total += n->m_len; \
if ((m)->m_pkthdr.len != total) { \
panic("%s: %d != %d", \
__FUNCTION__, (m)->m_pkthdr.len, total); \
} \
} while (0)
#else
#define CHECK_DATA_MBUF(m)
#endif
/************************************************************************
Node routines
************************************************************************/
/*
* Instantiate a node of the requested type
*/
int
ng_make_node(const char *typename, node_p *nodepp)
{
struct ng_type *type;
/* Check that the type makes sense */
if (typename == NULL) {
TRAP_ERROR;
return (EINVAL);
}
/* Locate the node type */
if ((type = ng_findtype(typename)) == NULL) {
char *path, filename[NG_TYPELEN + 4];
linker_file_t lf;
int error;
/* Not found, try to load it as a loadable module */
snprintf(filename, sizeof(filename), "ng_%s.ko", typename);
if ((path = linker_search_path(filename)) == NULL)
return (ENXIO);
error = linker_load_file(path, &lf);
FREE(path, M_LINKER);
if (error != 0)
return (error);
lf->userrefs++; /* pretend loaded by the syscall */
/* Try again, as now the type should have linked itself in */
if ((type = ng_findtype(typename)) == NULL)
return (ENXIO);
}
/* Call the constructor */
if (type->constructor != NULL)
return ((*type->constructor)(nodepp));
else
return (ng_make_node_common(type, nodepp));
}
/*
* Generic node creation. Called by node constructors.
* The returned node has a reference count of 1.
*/
int
ng_make_node_common(struct ng_type *type, node_p *nodepp)
{
node_p node;
/* Require the node type to have been already installed */
if (ng_findtype(type->name) == NULL) {
TRAP_ERROR;
return (EINVAL);
}
/* Make a node and try attach it to the type */
MALLOC(node, node_p, sizeof(*node), M_NETGRAPH, M_WAITOK);
if (node == NULL) {
TRAP_ERROR;
return (ENOMEM);
}
bzero(node, sizeof(*node));
node->type = type;
node->refs++; /* note reference */
type->refs++;
/* Link us into the node linked list */
LIST_INSERT_HEAD(&nodelist, node, nodes);
/* Initialize hook list for new node */
LIST_INIT(&node->hooks);
/* get an ID and put us in the hash chain */
node->ID = nextID++; /* 137 per second for 1 year before wrap */
LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes);
/* Done */
*nodepp = node;
return (0);
}
/*
* Forceably start the shutdown process on a node. Either call
* it's shutdown method, or do the default shutdown if there is
* no type-specific method.
*
* Persistent nodes must have a type-specific method which
* resets the NG_INVALID flag.
*/
void
ng_rmnode(node_p node)
{
/* Check if it's already shutting down */
if ((node->flags & NG_INVALID) != 0)
return;
/* Add an extra reference so it doesn't go away during this */
node->refs++;
/* Mark it invalid so any newcomers know not to try use it */
node->flags |= NG_INVALID;
/* Ask the type if it has anything to do in this case */
if (node->type && node->type->shutdown)
(*node->type->shutdown)(node);
else { /* do the default thing */
ng_unname(node);
ng_cutlinks(node);
ng_unref(node);
}
/* Remove extra reference, possibly the last */
ng_unref(node);
}
/*
* Called by the destructor to remove any STANDARD external references
*/
void
ng_cutlinks(node_p node)
{
hook_p hook;
/* Make sure that this is set to stop infinite loops */
node->flags |= NG_INVALID;
/* If we have sleepers, wake them up; they'll see NG_INVALID */
if (node->sleepers)
wakeup(node);
/* Notify all remaining connected nodes to disconnect */
while ((hook = LIST_FIRST(&node->hooks)) != NULL)
ng_destroy_hook(hook);
}
/*
* Remove a reference to the node, possibly the last
*/
void
ng_unref(node_p node)
{
if (--node->refs <= 0) {
node->type->refs--;
LIST_REMOVE(node, nodes);
LIST_REMOVE(node, idnodes);
FREE(node, M_NETGRAPH);
}
}
/*
* Wait for a node to come ready. Returns a node with a reference count;
* don't forget to drop it when we are done with it using ng_release_node().
*/
int
ng_wait_node(node_p node, char *msg)
{
int s, error = 0;
if (msg == NULL)
msg = "netgraph";
s = splnet();
node->sleepers++;
node->refs++; /* the sleeping process counts as a reference */
while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY)
error = tsleep(node, (PZERO + 1) | PCATCH, msg, 0);
node->sleepers--;
if (node->flags & NG_INVALID) {
TRAP_ERROR;
error = ENXIO;
} else {
KASSERT(node->refs > 1,
("%s: refs=%d", __FUNCTION__, node->refs));
node->flags |= NG_BUSY;
}
splx(s);
/* Release the reference we had on it */
if (error != 0)
ng_unref(node);
return error;
}
/*
* Release a node acquired via ng_wait_node()
*/
void
ng_release_node(node_p node)
{
/* Declare that we don't want it */
node->flags &= ~NG_BUSY;
/* If we have sleepers, then wake them up */
if (node->sleepers)
wakeup(node);
/* We also have a reference.. drop it too */
ng_unref(node);
}
/************************************************************************
Node ID handling
************************************************************************/
static node_p
ng_ID2node(ng_ID_t ID)
{
node_p np;
LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) {
if (np->ID == ID)
break;
}
return(np);
}
ng_ID_t
ng_node2ID(node_p node)
{
return (node->ID);
}
/************************************************************************
Node name handling
************************************************************************/
/*
* Assign a node a name. Once assigned, the name cannot be changed.
*/
int
ng_name_node(node_p node, const char *name)
{
int i;
/* Check the name is valid */
for (i = 0; i < NG_NODELEN + 1; i++) {
if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
break;
}
if (i == 0 || name[i] != '\0') {
TRAP_ERROR;
return (EINVAL);
}
if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
TRAP_ERROR;
return (EINVAL);
}
/* Check the node isn't already named */
if (node->name != NULL) {
TRAP_ERROR;
return (EISCONN);
}
/* Check the name isn't already being used */
if (ng_findname(node, name) != NULL) {
TRAP_ERROR;
return (EADDRINUSE);
}
/* Allocate space and copy it */
MALLOC(node->name, char *, strlen(name) + 1, M_NETGRAPH, M_WAITOK);
if (node->name == NULL) {
TRAP_ERROR;
return (ENOMEM);
}
strcpy(node->name, name);
/* The name counts as a reference */
node->refs++;
return (0);
}
/*
* Find a node by absolute name. The name should NOT end with ':'
* The name "." means "this node" and "[xxx]" means "the node
* with ID (ie, at address) xxx".
*
* Returns the node if found, else NULL.
*/
node_p
ng_findname(node_p this, const char *name)
{
node_p node;
ng_ID_t temp;
/* "." means "this node" */
if (strcmp(name, ".") == 0)
return(this);
/* Check for name-by-ID */
if ((temp = ng_decodeidname(name)) != 0) {
return (ng_ID2node(temp));
}
/* Find node by name */
LIST_FOREACH(node, &nodelist, nodes) {
if (node->name != NULL && strcmp(node->name, name) == 0)
break;
}
return (node);
}
/*
* Decode a ID name, eg. "[f03034de]". Returns 0 if the
* string is not valid, otherwise returns the value.
*/
static ng_ID_t
ng_decodeidname(const char *name)
{
const int len = strlen(name);
char *eptr;
u_long val;
/* Check for proper length, brackets, no leading junk */
if (len < 3 || name[0] != '[' || name[len - 1] != ']'
|| !isxdigit(name[1]))
return (0);
/* Decode number */
val = strtoul(name + 1, &eptr, 16);
if (eptr - name != len - 1 || val == ULONG_MAX || val == 0)
return ((ng_ID_t)0);
return (ng_ID_t)val;
}
/*
* Remove a name from a node. This should only be called
* when shutting down and removing the node.
*/
void
ng_unname(node_p node)
{
if (node->name) {
FREE(node->name, M_NETGRAPH);
node->name = NULL;
ng_unref(node);
}
}
/************************************************************************
Hook routines
Names are not optional. Hooks are always connected, except for a
brief moment within these routines.
************************************************************************/
/*
* Remove a hook reference
*/
static void
ng_unref_hook(hook_p hook)
{
if (--hook->refs == 0)
FREE(hook, M_NETGRAPH);
}
/*
* Add an unconnected hook to a node. Only used internally.
*/
static int
ng_add_hook(node_p node, const char *name, hook_p *hookp)
{
hook_p hook;
int error = 0;
/* Check that the given name is good */
if (name == NULL) {
TRAP_ERROR;
return (EINVAL);
}
LIST_FOREACH(hook, &node->hooks, hooks) {
if (strcmp(hook->name, name) == 0) {
TRAP_ERROR;
return (EEXIST);
}
}
/* Allocate the hook and link it up */
MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH, M_WAITOK);
if (hook == NULL) {
TRAP_ERROR;
return (ENOMEM);
}
bzero(hook, sizeof(*hook));
hook->refs = 1;
hook->flags = HK_INVALID;
hook->node = node;
node->refs++; /* each hook counts as a reference */
/* Check if the node type code has something to say about it */
if (node->type->newhook != NULL)
if ((error = (*node->type->newhook)(node, hook, name)) != 0)
goto fail;
/*
* The 'type' agrees so far, so go ahead and link it in.
* We'll ask again later when we actually connect the hooks.
*/
LIST_INSERT_HEAD(&node->hooks, hook, hooks);
node->numhooks++;
/* Set hook name */
MALLOC(hook->name, char *, strlen(name) + 1, M_NETGRAPH, M_WAITOK);
if (hook->name == NULL) {
error = ENOMEM;
LIST_REMOVE(hook, hooks);
node->numhooks--;
fail:
hook->node = NULL;
ng_unref(node);
ng_unref_hook(hook); /* this frees the hook */
return (error);
}
strcpy(hook->name, name);
if (hookp)
*hookp = hook;
return (error);
}
/*
* Connect a pair of hooks. Only used internally.
*/
static int
ng_connect(hook_p hook1, hook_p hook2)
{
int error;
hook1->peer = hook2;
hook2->peer = hook1;
/* Give each node the opportunity to veto the impending connection */
if (hook1->node->type->connect) {
if ((error = (*hook1->node->type->connect) (hook1))) {
ng_destroy_hook(hook1); /* also zaps hook2 */
return (error);
}
}
if (hook2->node->type->connect) {
if ((error = (*hook2->node->type->connect) (hook2))) {
ng_destroy_hook(hook2); /* also zaps hook1 */
return (error);
}
}
hook1->flags &= ~HK_INVALID;
hook2->flags &= ~HK_INVALID;
return (0);
}
/*
* Destroy a hook
*
* As hooks are always attached, this really destroys two hooks.
* The one given, and the one attached to it. Disconnect the hooks
* from each other first.
*/
void
ng_destroy_hook(hook_p hook)
{
hook_p peer = hook->peer;
hook->flags |= HK_INVALID; /* as soon as possible */
if (peer) {
peer->flags |= HK_INVALID; /* as soon as possible */
hook->peer = NULL;
peer->peer = NULL;
ng_disconnect_hook(peer);
}
ng_disconnect_hook(hook);
}
/*
* Notify the node of the hook's demise. This may result in more actions
* (e.g. shutdown) but we don't do that ourselves and don't know what
* happens there. If there is no appropriate handler, then just remove it
* (and decrement the reference count of it's node which in turn might
* make something happen).
*/
static void
ng_disconnect_hook(hook_p hook)
{
node_p node = hook->node;
/*
* Remove the hook from the node's list to avoid possible recursion
* in case the disconnection results in node shutdown.
*/
LIST_REMOVE(hook, hooks);
node->numhooks--;
if (node->type->disconnect) {
/*
* The type handler may elect to destroy the peer so don't
* trust its existance after this point.
*/
(*node->type->disconnect) (hook);
}
ng_unref(node); /* might be the last reference */
if (hook->name)
FREE(hook->name, M_NETGRAPH);
hook->node = NULL; /* may still be referenced elsewhere */
ng_unref_hook(hook);
}
/*
* Take two hooks on a node and merge the connection so that the given node
* is effectively bypassed.
*/
int
ng_bypass(hook_p hook1, hook_p hook2)
{
if (hook1->node != hook2->node)
return (EINVAL);
hook1->peer->peer = hook2->peer;
hook2->peer->peer = hook1->peer;
/* XXX If we ever cache methods on hooks update them as well */
hook1->peer = NULL;
hook2->peer = NULL;
ng_destroy_hook(hook1);
ng_destroy_hook(hook2);
return (0);
}
/*
* Install a new netgraph type
*/
int
ng_newtype(struct ng_type *tp)
{
const size_t namelen = strlen(tp->name);
/* Check version and type name fields */
if (tp->version != NG_VERSION || namelen == 0 || namelen > NG_TYPELEN) {
TRAP_ERROR;
return (EINVAL);
}
/* Check for name collision */
if (ng_findtype(tp->name) != NULL) {
TRAP_ERROR;
return (EEXIST);
}
/* Link in new type */
LIST_INSERT_HEAD(&typelist, tp, types);
tp->refs = 0;
return (0);
}
/*
* Look for a type of the name given
*/
struct ng_type *
ng_findtype(const char *typename)
{
struct ng_type *type;
LIST_FOREACH(type, &typelist, types) {
if (strcmp(type->name, typename) == 0)
break;
}
return (type);
}
/************************************************************************
Composite routines
************************************************************************/
/*
* Make a peer and connect. The order is arranged to minimise
* the work needed to back out in case of error.
*/
int
ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
{
node_p node2;
hook_p hook;
hook_p hook2;
int error;
if ((error = ng_add_hook(node, name, &hook)))
return (error);
if ((error = ng_make_node(type, &node2))) {
ng_destroy_hook(hook);
return (error);
}
if ((error = ng_add_hook(node2, name2, &hook2))) {
ng_rmnode(node2);
ng_destroy_hook(hook);
return (error);
}
/*
* Actually link the two hooks together.. on failure they are
* destroyed so we don't have to do that here.
*/
if ((error = ng_connect(hook, hook2)))
ng_rmnode(node2);
return (error);
}
/*
* Connect two nodes using the specified hooks
*/
int
ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2)
{
int error;
hook_p hook;
hook_p hook2;
if ((error = ng_add_hook(node, name, &hook)))
return (error);
if ((error = ng_add_hook(node2, name2, &hook2))) {
ng_destroy_hook(hook);
return (error);
}
return (ng_connect(hook, hook2));
}
/*
* Parse and verify a string of the form: <NODE:><PATH>
*
* Such a string can refer to a specific node or a specific hook
* on a specific node, depending on how you look at it. In the
* latter case, the PATH component must not end in a dot.
*
* Both <NODE:> and <PATH> are optional. The <PATH> is a string
* of hook names separated by dots. This breaks out the original
* string, setting *nodep to "NODE" (or NULL if none) and *pathp
* to "PATH" (or NULL if degenerate). Also, *hookp will point to
* the final hook component of <PATH>, if any, otherwise NULL.
*
* This returns -1 if the path is malformed. The char ** are optional.
*/
int
ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
{
char *node, *path, *hook;
int k;
/*
* Extract absolute NODE, if any
*/
for (path = addr; *path && *path != ':'; path++);
if (*path) {
node = addr; /* Here's the NODE */
*path++ = '\0'; /* Here's the PATH */
/* Node name must not be empty */
if (!*node)
return -1;
/* A name of "." is OK; otherwise '.' not allowed */
if (strcmp(node, ".") != 0) {
for (k = 0; node[k]; k++)
if (node[k] == '.')
return -1;
}
} else {
node = NULL; /* No absolute NODE */
path = addr; /* Here's the PATH */
}
/* Snoop for illegal characters in PATH */
for (k = 0; path[k]; k++)
if (path[k] == ':')
return -1;
/* Check for no repeated dots in PATH */
for (k = 0; path[k]; k++)
if (path[k] == '.' && path[k + 1] == '.')
return -1;
/* Remove extra (degenerate) dots from beginning or end of PATH */
if (path[0] == '.')
path++;
if (*path && path[strlen(path) - 1] == '.')
path[strlen(path) - 1] = 0;
/* If PATH has a dot, then we're not talking about a hook */
if (*path) {
for (hook = path, k = 0; path[k]; k++)
if (path[k] == '.') {
hook = NULL;
break;
}
} else
path = hook = NULL;
/* Done */
if (nodep)
*nodep = node;
if (pathp)
*pathp = path;
if (hookp)
*hookp = hook;
return (0);
}
/*
* Given a path, which may be absolute or relative, and a starting node,
* return the destination node. Compute the "return address" if desired.
*/
int
ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp)
{
const node_p start = here;
char fullpath[NG_PATHLEN + 1];
char *nodename, *path, pbuf[2];
node_p node;
char *cp;
/* Initialize */
if (rtnp)
*rtnp = NULL;
if (destp == NULL)
return EINVAL;
*destp = NULL;
/* Make a writable copy of address for ng_path_parse() */
strncpy(fullpath, address, sizeof(fullpath) - 1);
fullpath[sizeof(fullpath) - 1] = '\0';
/* Parse out node and sequence of hooks */
if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
TRAP_ERROR;
return EINVAL;
}
if (path == NULL) {
pbuf[0] = '.'; /* Needs to be writable */
pbuf[1] = '\0';
path = pbuf;
}
/* For an absolute address, jump to the starting node */
if (nodename) {
node = ng_findname(here, nodename);
if (node == NULL) {
TRAP_ERROR;
return (ENOENT);
}
} else
node = here;
/* Now follow the sequence of hooks */
for (cp = path; node != NULL && *cp != '\0'; ) {
hook_p hook;
char *segment;
/*
* Break out the next path segment. Replace the dot we just
* found with a NUL; "cp" points to the next segment (or the
* NUL at the end).
*/
for (segment = cp; *cp != '\0'; cp++) {
if (*cp == '.') {
*cp++ = '\0';
break;
}
}
/* Empty segment */
if (*segment == '\0')
continue;
/* We have a segment, so look for a hook by that name */
LIST_FOREACH(hook, &node->hooks, hooks) {
if (hook->name && strcmp(hook->name, segment) == 0)
break;
}
/* Can't get there from here... */
if (hook == NULL
|| hook->peer == NULL
|| (hook->flags & HK_INVALID) != 0) {
TRAP_ERROR;
return (ENOENT);
}
/* Hop on over to the next node */
node = hook->peer->node;
}
/* If node somehow missing, fail here (probably this is not needed) */
if (node == NULL) {
TRAP_ERROR;
return (ENXIO);
}
/* Now compute return address, i.e., the path to the sender */
if (rtnp != NULL) {
MALLOC(*rtnp, char *, NG_NODELEN + 2, M_NETGRAPH, M_WAITOK);
if (*rtnp == NULL) {
TRAP_ERROR;
return (ENOMEM);
}
if (start->name != NULL)
sprintf(*rtnp, "%s:", start->name);
else
sprintf(*rtnp, "[%x]:", ng_node2ID(start));
}
/* Done */
*destp = node;
return (0);
}
/*
* Call the appropriate message handler for the object.
* It is up to the message handler to free the message.
* If it's a generic message, handle it generically, otherwise
* call the type's message handler (if it exists)
*/
#define CALL_MSG_HANDLER(error, node, msg, retaddr, resp) \
do { \
if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \
(error) = ng_generic_msg((node), (msg), \
(retaddr), (resp)); \
} else { \
if ((node)->type->rcvmsg != NULL) { \
(error) = (*(node)->type->rcvmsg)((node), \
(msg), (retaddr), (resp)); \
} else { \
TRAP_ERROR; \
FREE((msg), M_NETGRAPH); \
(error) = EINVAL; \
} \
} \
} while (0)
/*
* Send a control message to a node
*/
int
ng_send_msg(node_p here, struct ng_mesg *msg, const char *address,
struct ng_mesg **rptr)
{
node_p dest = NULL;
char *retaddr = NULL;
int error;
/* Find the target node */
error = ng_path2node(here, address, &dest, &retaddr);
if (error) {
FREE(msg, M_NETGRAPH);
return error;
}
/* Make sure the resp field is null before we start */
if (rptr != NULL)
*rptr = NULL;
CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr);
/* Make sure that if there is a response, it has the RESP bit set */
if ((error == 0) && rptr && *rptr)
(*rptr)->header.flags |= NGF_RESP;
/*
* If we had a return address it is up to us to free it. They should
* have taken a copy if they needed to make a delayed response.
*/
if (retaddr)
FREE(retaddr, M_NETGRAPH);
return (error);
}
/*
* Implement the 'generic' control messages
*/
static int
ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr,
struct ng_mesg **resp)
{
int error = 0;
if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
TRAP_ERROR;
FREE(msg, M_NETGRAPH);
return (EINVAL);
}
switch (msg->header.cmd) {
case NGM_SHUTDOWN:
ng_rmnode(here);
break;
case NGM_MKPEER:
{
struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
if (msg->header.arglen != sizeof(*mkp)) {
TRAP_ERROR;
return (EINVAL);
}
mkp->type[sizeof(mkp->type) - 1] = '\0';
mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
break;
}
case NGM_CONNECT:
{
struct ngm_connect *const con =
(struct ngm_connect *) msg->data;
node_p node2;
if (msg->header.arglen != sizeof(*con)) {
TRAP_ERROR;
return (EINVAL);
}
con->path[sizeof(con->path) - 1] = '\0';
con->ourhook[sizeof(con->ourhook) - 1] = '\0';
con->peerhook[sizeof(con->peerhook) - 1] = '\0';
error = ng_path2node(here, con->path, &node2, NULL);
if (error)
break;
error = ng_con_nodes(here, con->ourhook, node2, con->peerhook);
break;
}
case NGM_NAME:
{
struct ngm_name *const nam = (struct ngm_name *) msg->data;
if (msg->header.arglen != sizeof(*nam)) {
TRAP_ERROR;
return (EINVAL);
}
nam->name[sizeof(nam->name) - 1] = '\0';
error = ng_name_node(here, nam->name);
break;
}
case NGM_RMHOOK:
{
struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
hook_p hook;
if (msg->header.arglen != sizeof(*rmh)) {
TRAP_ERROR;
return (EINVAL);
}
rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
LIST_FOREACH(hook, &here->hooks, hooks) {
if (hook->name && strcmp(hook->name, rmh->ourhook) == 0)
break;
}
if (hook)
ng_destroy_hook(hook);
break;
}
case NGM_NODEINFO:
{
struct nodeinfo *ni;
struct ng_mesg *rp;
/* Get response struct */
if (resp == NULL) {
error = EINVAL;
break;
}
NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT);
if (rp == NULL) {
error = ENOMEM;
break;
}
/* Fill in node info */
ni = (struct nodeinfo *) rp->data;
if (here->name != NULL)
strncpy(ni->name, here->name, NG_NODELEN);
strncpy(ni->type, here->type->name, NG_TYPELEN);
ni->id = ng_node2ID(here);
ni->hooks = here->numhooks;
*resp = rp;
break;
}
case NGM_LISTHOOKS:
{
const int nhooks = here->numhooks;
struct hooklist *hl;
struct nodeinfo *ni;
struct ng_mesg *rp;
hook_p hook;
/* Get response struct */
if (resp == NULL) {
error = EINVAL;
break;
}
NG_MKRESPONSE(rp, msg, sizeof(*hl)
+ (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
if (rp == NULL) {
error = ENOMEM;
break;
}
hl = (struct hooklist *) rp->data;
ni = &hl->nodeinfo;
/* Fill in node info */
if (here->name)
strncpy(ni->name, here->name, NG_NODELEN);
strncpy(ni->type, here->type->name, NG_TYPELEN);
ni->id = ng_node2ID(here);
/* Cycle through the linked list of hooks */
ni->hooks = 0;
LIST_FOREACH(hook, &here->hooks, hooks) {
struct linkinfo *const link = &hl->link[ni->hooks];
if (ni->hooks >= nhooks) {
log(LOG_ERR, "%s: number of %s changed\n",
__FUNCTION__, "hooks");
break;
}
if ((hook->flags & HK_INVALID) != 0)
continue;
strncpy(link->ourhook, hook->name, NG_HOOKLEN);
strncpy(link->peerhook, hook->peer->name, NG_HOOKLEN);
if (hook->peer->node->name != NULL)
strncpy(link->nodeinfo.name,
hook->peer->node->name, NG_NODELEN);
strncpy(link->nodeinfo.type,
hook->peer->node->type->name, NG_TYPELEN);
link->nodeinfo.id = ng_node2ID(hook->peer->node);
link->nodeinfo.hooks = hook->peer->node->numhooks;
ni->hooks++;
}
*resp = rp;
break;
}
case NGM_LISTNAMES:
case NGM_LISTNODES:
{
const int unnamed = (msg->header.cmd == NGM_LISTNODES);
struct namelist *nl;
struct ng_mesg *rp;
node_p node;
int num = 0;
if (resp == NULL) {
error = EINVAL;
break;
}
/* Count number of nodes */
LIST_FOREACH(node, &nodelist, nodes) {
if (unnamed || node->name != NULL)
num++;
}
/* Get response struct */
if (resp == NULL) {
error = EINVAL;
break;
}
NG_MKRESPONSE(rp, msg, sizeof(*nl)
+ (num * sizeof(struct nodeinfo)), M_NOWAIT);
if (rp == NULL) {
error = ENOMEM;
break;
}
nl = (struct namelist *) rp->data;
/* Cycle through the linked list of nodes */
nl->numnames = 0;
LIST_FOREACH(node, &nodelist, nodes) {
struct nodeinfo *const np = &nl->nodeinfo[nl->numnames];
if (nl->numnames >= num) {
log(LOG_ERR, "%s: number of %s changed\n",
__FUNCTION__, "nodes");
break;
}
if ((node->flags & NG_INVALID) != 0)
continue;
if (!unnamed && node->name == NULL)
continue;
if (node->name != NULL)
strncpy(np->name, node->name, NG_NODELEN);
strncpy(np->type, node->type->name, NG_TYPELEN);
np->id = ng_node2ID(node);
np->hooks = node->numhooks;
nl->numnames++;
}
*resp = rp;
break;
}
case NGM_LISTTYPES:
{
struct typelist *tl;
struct ng_mesg *rp;
struct ng_type *type;
int num = 0;
if (resp == NULL) {
error = EINVAL;
break;
}
/* Count number of types */
LIST_FOREACH(type, &typelist, types)
num++;
/* Get response struct */
if (resp == NULL) {
error = EINVAL;
break;
}
NG_MKRESPONSE(rp, msg, sizeof(*tl)
+ (num * sizeof(struct typeinfo)), M_NOWAIT);
if (rp == NULL) {
error = ENOMEM;
break;
}
tl = (struct typelist *) rp->data;
/* Cycle through the linked list of types */
tl->numtypes = 0;
LIST_FOREACH(type, &typelist, types) {
struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
if (tl->numtypes >= num) {
log(LOG_ERR, "%s: number of %s changed\n",
__FUNCTION__, "types");
break;
}
strncpy(tp->typename, type->name, NG_TYPELEN);
tp->numnodes = type->refs;
tl->numtypes++;
}
*resp = rp;
break;
}
case NGM_TEXT_STATUS:
/*
* This one is tricky as it passes the command down to the
* actual node, even though it is a generic type command.
* This means we must assume that the msg is already freed
* when control passes back to us.
*/
if (resp == NULL) {
error = EINVAL;
break;
}
if (here->type->rcvmsg != NULL)
return((*here->type->rcvmsg)(here, msg, retaddr, resp));
/* Fall through if rcvmsg not supported */
default:
TRAP_ERROR;
error = EINVAL;
}
FREE(msg, M_NETGRAPH);
return (error);
}
/*
* Send a data packet to a node. If the recipient has no
* 'receive data' method, then silently discard the packet.
*/
int
ng_send_data(hook_p hook, struct mbuf *m, meta_p meta)
{
int (*rcvdata)(hook_p, struct mbuf *, meta_p);
int error;
CHECK_DATA_MBUF(m);
if (hook && (hook->flags & HK_INVALID) == 0) {
rcvdata = hook->peer->node->type->rcvdata;
if (rcvdata != NULL)
error = (*rcvdata)(hook->peer, m, meta);
else {
error = 0;
NG_FREE_DATA(m, meta);
}
} else {
TRAP_ERROR;
error = ENOTCONN;
NG_FREE_DATA(m, meta);
}
return (error);
}
/*
* Send a queued data packet to a node. If the recipient has no
* 'receive queued data' method, then try the 'receive data' method above.
*/
int
ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta)
{
int (*rcvdataq)(hook_p, struct mbuf *, meta_p);
int error;
CHECK_DATA_MBUF(m);
if (hook && (hook->flags & HK_INVALID) == 0) {
rcvdataq = hook->peer->node->type->rcvdataq;
if (rcvdataq != NULL)
error = (*rcvdataq)(hook->peer, m, meta);
else {
error = ng_send_data(hook, m, meta);
}
} else {
TRAP_ERROR;
error = ENOTCONN;
NG_FREE_DATA(m, meta);
}
return (error);
}
/************************************************************************
Module routines
************************************************************************/
/*
* Handle the loading/unloading of a netgraph node type module
*/
int
ng_mod_event(module_t mod, int event, void *data)
{
struct ng_type *const type = data;
int s, error = 0;
switch (event) {
case MOD_LOAD:
/* Register new netgraph node type */
s = splnet();
if ((error = ng_newtype(type)) != 0) {
splx(s);
break;
}
/* Call type specific code */
if (type->mod_event != NULL)
if ((error = (*type->mod_event)(mod, event, data)) != 0)
LIST_REMOVE(type, types);
splx(s);
break;
case MOD_UNLOAD:
s = splnet();
if (type->refs != 0) /* make sure no nodes exist! */
error = EBUSY;
else {
if (type->mod_event != NULL) { /* check with type */
error = (*type->mod_event)(mod, event, data);
if (error != 0) { /* type refuses.. */
splx(s);
break;
}
}
LIST_REMOVE(type, types);
}
splx(s);
break;
default:
if (type->mod_event != NULL)
error = (*type->mod_event)(mod, event, data);
else
error = 0; /* XXX ? */
break;
}
return (error);
}
/*
* Handle loading and unloading for this code.
* The only thing we need to link into is the NETISR strucure.
*/
static int
ngb_mod_event(module_t mod, int event, void *data)
{
int s, error = 0;
switch (event) {
case MOD_LOAD:
/* Register line discipline */
s = splimp();
error = register_netisr(NETISR_NETGRAPH, ngintr);
splx(s);
break;
case MOD_UNLOAD:
/* You cant unload it because an interface may be using it. */
error = EBUSY;
break;
default:
error = EOPNOTSUPP;
break;
}
return (error);
}
static moduledata_t netgraph_mod = {
"netgraph",
ngb_mod_event,
(NULL)
};
DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
/************************************************************************
Queueing routines
************************************************************************/
/* The structure for queueing across ISR switches */
struct ng_queue_entry {
u_long flags;
struct ng_queue_entry *next;
union {
struct {
hook_p da_hook; /* target hook */
struct mbuf *da_m;
meta_p da_meta;
} data;
struct {
struct ng_mesg *msg_msg;
node_p msg_node;
void *msg_retaddr;
} msg;
} body;
};
#define NGQF_DATA 0x01 /* the queue element is data */
#define NGQF_MESG 0x02 /* the queue element is a message */
static struct ng_queue_entry *ngqbase; /* items to be unqueued */
static struct ng_queue_entry *ngqlast; /* last item queued */
static const int ngqroom = 64; /* max items to queue */
static int ngqsize; /* number of items in queue */
static struct ng_queue_entry *ngqfree; /* free ones */
static const int ngqfreemax = 16;/* cache at most this many */
static int ngqfreesize; /* number of cached entries */
/*
* Get a queue entry
*/
static struct ng_queue_entry *
ng_getqblk(void)
{
register struct ng_queue_entry *q;
int s;
/* Could be guarding against tty ints or whatever */
s = splhigh();
/* Try get a cached queue block, or else allocate a new one */
if ((q = ngqfree) == NULL) {
splx(s);
if (ngqsize < ngqroom) { /* don't worry about races */
MALLOC(q, struct ng_queue_entry *,
sizeof(*q), M_NETGRAPH, M_NOWAIT);
}
} else {
ngqfree = q->next;
ngqfreesize--;
splx(s);
}
return (q);
}
/*
* Release a queue entry
*/
#define RETURN_QBLK(q) \
do { \
int s; \
if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \
s = splhigh(); \
(q)->next = ngqfree; \
ngqfree = (q); \
ngqfreesize++; \
splx(s); \
} else { \
FREE((q), M_NETGRAPH); \
} \
} while (0)
/*
* Running at a raised (but we don't know which) processor priority level,
* put the data onto a queue to be picked up by another PPL (probably splnet)
*/
int
ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta)
{
struct ng_queue_entry *q;
int s;
if (hook == NULL) {
NG_FREE_DATA(m, meta);
return (0);
}
if ((q = ng_getqblk()) == NULL) {
NG_FREE_DATA(m, meta);
return (ENOBUFS);
}
/* Fill out the contents */
q->flags = NGQF_DATA;
q->next = NULL;
q->body.data.da_hook = hook;
q->body.data.da_m = m;
q->body.data.da_meta = meta;
hook->refs++; /* don't let it go away while on the queue */
/* Put it on the queue */
s = splhigh();
if (ngqbase) {
ngqlast->next = q;
} else {
ngqbase = q;
}
ngqlast = q;
ngqsize++;
splx(s);
/* Schedule software interrupt to handle it later */
schednetisr(NETISR_NETGRAPH);
return (0);
}
/*
* Running at a raised (but we don't know which) processor priority level,
* put the msg onto a queue to be picked up by another PPL (probably splnet)
*/
int
ng_queue_msg(node_p here, struct ng_mesg * msg, int len, const char *address)
{
register struct ng_queue_entry *q;
int s;
node_p dest = NULL;
char *retaddr = NULL;
int error;
/* Find the target node. */
error = ng_path2node(here, address, &dest, &retaddr);
if (error) {
FREE(msg, M_NETGRAPH);
return (error);
}
if ((q = ng_getqblk()) == NULL) {
FREE(msg, M_NETGRAPH);
if (retaddr)
FREE(retaddr, M_NETGRAPH);
return (ENOBUFS);
}
/* Fill out the contents */
q->flags = NGQF_MESG;
q->next = NULL;
q->body.msg.msg_node = dest;
q->body.msg.msg_msg = msg;
q->body.msg.msg_retaddr = retaddr;
dest->refs++; /* don't let it go away while on the queue */
/* Put it on the queue */
s = splhigh();
if (ngqbase) {
ngqlast->next = q;
} else {
ngqbase = q;
}
ngqlast = q;
ngqsize++;
splx(s);
/* Schedule software interrupt to handle it later */
schednetisr(NETISR_NETGRAPH);
return (0);
}
/*
* Pick an item off the queue, process it, and dispose of the queue entry.
* Should be running at splnet.
*/
static void
ngintr(void)
{
hook_p hook;
struct ng_queue_entry *ngq;
struct mbuf *m;
meta_p meta;
void *retaddr;
struct ng_mesg *msg;
node_p node;
int error = 0;
int s;
while (1) {
s = splhigh();
if ((ngq = ngqbase)) {
ngqbase = ngq->next;
ngqsize--;
}
splx(s);
if (ngq == NULL)
return;
switch (ngq->flags) {
case NGQF_DATA:
hook = ngq->body.data.da_hook;
m = ngq->body.data.da_m;
meta = ngq->body.data.da_meta;
RETURN_QBLK(ngq);
NG_SEND_DATAQ(error, hook, m, meta);
ng_unref_hook(hook);
break;
case NGQF_MESG:
node = ngq->body.msg.msg_node;
msg = ngq->body.msg.msg_msg;
retaddr = ngq->body.msg.msg_retaddr;
RETURN_QBLK(ngq);
if (node->flags & NG_INVALID) {
FREE(msg, M_NETGRAPH);
} else {
CALL_MSG_HANDLER(error, node, msg,
retaddr, NULL);
}
ng_unref(node);
if (retaddr)
FREE(retaddr, M_NETGRAPH);
break;
default:
RETURN_QBLK(ngq);
}
}
}
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