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-rw-r--r--common/snmp-engine.c191
1 files changed, 122 insertions, 69 deletions
diff --git a/common/snmp-engine.c b/common/snmp-engine.c
index 35fae26..0bfb77d 100644
--- a/common/snmp-engine.c
+++ b/common/snmp-engine.c
@@ -305,10 +305,20 @@ host_cleanup (void)
* ASYNC REQUEST PROCESSING
*/
+#define MAKE_REQUEST_ID(snmp, cb) \
+ ((((snmp) & 0xFFFFFF) << 8) | (cb & 0xFF))
+#define REQUEST_ID_SNMP(id) \
+ ((id) >> 8)
+#define REQUEST_ID_CB(id) \
+ ((id) & 0xFF)
+
struct request
{
/* The SNMP request identifier */
- uint id;
+ uint snmp_id;
+
+ /* References, useful since we have callbacks */
+ int refs;
mstime next_send; /* Time of the next packet send */
mstime last_sent; /* Time last sent */
@@ -332,7 +342,7 @@ struct request
static int snmp_retries = 3;
/* The last request id */
-static uint snmp_request_id = 100000;
+static uint snmp_request_id = 1;
/* The SNMP socket we're communicating on */
static int snmp_socket = -1;
@@ -353,8 +363,8 @@ static void
request_release (struct request *req)
{
/* It should no longer be referred to any of these places */
- ASSERT (!hsh_get (snmp_preparing, &req->id, sizeof (req->id)));
- ASSERT (!hsh_get (snmp_processing, &req->id, sizeof (req->id)));
+ ASSERT (!hsh_get (snmp_preparing, &req->snmp_id, sizeof (req->snmp_id)));
+ ASSERT (!hsh_get (snmp_processing, &req->snmp_id, sizeof (req->snmp_id)));
snmp_pdu_clear (&req->pdu);
free (req);
@@ -394,7 +404,7 @@ request_send (struct request* req, mstime when)
if (ret == -1)
log_error ("couldn't send snmp packet to: %s", req->host->hostname);
else
- log_debug ("sent request #%d to: %s", req->id, req->host->hostname);
+ log_debug ("sent request #%d to: %s", req->snmp_id, req->host->hostname);
}
}
@@ -406,18 +416,30 @@ request_failure (struct request *req, int code)
ASSERT (req);
ASSERT (code != 0);
+ ASSERT (hsh_get (snmp_processing, &req->snmp_id, sizeof (req->snmp_id)) == req);
- log_debug ("failed request #%d to '%s' with code %d", req->id, req->host->hostname, code);
+ log_debug ("failed request #%d to '%s' with code %d", req->snmp_id, req->host->hostname, code);
/* For each request SNMP value... */
for (j = 0; j < req->pdu.nbindings; ++j) {
+
+ if (!req->callbacks[j].func)
+ continue;
+
/* ... let callback know */
- if (req->callbacks[j].func)
- (req->callbacks[j].func) (req->id, code, NULL, req->callbacks[j].arg);
+ (req->callbacks[j].func) (MAKE_REQUEST_ID (req->snmp_id, j),
+ code, NULL, req->callbacks[j].arg);
+
+ /*
+ * Request could have been freed by the callback, by calling the cancel
+ * function, check and bail if so.
+ */
+ if (hsh_get (snmp_processing, &req->snmp_id, sizeof (req->snmp_id)) != req)
+ return;
}
/* Remove from the processing list */
- val = hsh_rem (snmp_processing, &req->id, sizeof (req->id));
+ val = hsh_rem (snmp_processing, &req->snmp_id, sizeof (req->snmp_id));
ASSERT (val == req);
/* And free the request */
@@ -429,24 +451,29 @@ request_get_dispatch (struct request* req, struct snmp_pdu* pdu)
{
struct snmp_value* pvalue;
struct snmp_value* rvalue;
- int i, j, last, processed;
+ int i, j, skipped, processed;
void *val;
ASSERT (req);
ASSERT (pdu);
- ASSERT (req->id == pdu->request_id);
+ ASSERT (req->snmp_id == pdu->request_id);
ASSERT (pdu->error_status == SNMP_ERR_NOERROR);
ASSERT (req->pdu.type == SNMP_PDU_GET);
+ ASSERT (hsh_get (snmp_processing, &req->snmp_id, sizeof (req->snmp_id)) == req);
/*
* For SNMP GET requests we check that the values that came back
* were in fact for the same values we requested, and fix any
* ordering issues etc.
*/
- for (j = 0; j < req->pdu.nbindings; ++j) {
+ skipped = 0;
+ for (j = 0; j < SNMP_MAX_BINDINGS; ++j) {
+
+ if (!req->callbacks[j].func)
+ continue;
- processed = 0;
rvalue = &(req->pdu.bindings[j]);
+ processed = 0;
/* ... dig out matching value from response */
for (i = 0; i < pdu->nbindings; ++i) {
@@ -455,37 +482,32 @@ request_get_dispatch (struct request* req, struct snmp_pdu* pdu)
if (asn_compare_oid (&(rvalue->var), &(pvalue->var)) != 0)
continue;
- if (req->callbacks[j].func)
- (req->callbacks[j].func) (req->id, SNMP_ERR_NOERROR,
- pvalue, req->callbacks[j].arg);
+ (req->callbacks[j].func) (MAKE_REQUEST_ID (req->snmp_id, j),
+ SNMP_ERR_NOERROR, pvalue, req->callbacks[j].arg);
+ /*
+ * Request could have been freed by the callback, by calling the cancel
+ * function, check and bail if so.
+ */
+ if (hsh_get (snmp_processing, &req->snmp_id, sizeof (req->snmp_id)) != req)
+ return;
+
+ req->callbacks[j].func = NULL;
processed = 1;
break;
}
- /* If this one was processed, remove from request */
- if (processed) {
- last = --req->pdu.nbindings;
-
- ASSERT (last >= 0);
- if (last) {
- memcpy (&req->callbacks[j], &req->callbacks[last], sizeof (req->callbacks[j]));
- memcpy (&req->pdu.bindings[j], &req->pdu.bindings[last], sizeof (req->pdu.bindings[j]));
- }
- memset (&req->callbacks[last], 0, sizeof (req->callbacks[last]));
- memset (&req->pdu.bindings[last], 0, sizeof (req->pdu.bindings[last]));
-
- /* Process this index again, since we have a new request here */
- --j;
- }
+ /* Make note that we didn't find a match for at least one binding */
+ if (!processed && !skipped)
+ skipped = 1;
}
/* All done? then remove request */
- if (req->pdu.nbindings == 0) {
+ if (!skipped) {
- log_debug ("request #%d is complete", req->id);
+ log_debug ("request #%d is complete", req->snmp_id);
- val = hsh_rem (snmp_processing, &req->id, sizeof (req->id));
+ val = hsh_rem (snmp_processing, &req->snmp_id, sizeof (req->snmp_id));
ASSERT (val == req);
request_release (req);
}
@@ -498,7 +520,7 @@ request_other_dispatch (struct request* req, struct snmp_pdu* pdu)
ASSERT (req);
ASSERT (pdu);
- ASSERT (req->id == pdu->request_id);
+ ASSERT (req->snmp_id == pdu->request_id);
ASSERT (pdu->error_status == SNMP_ERR_NOERROR);
ASSERT (req->pdu.type != SNMP_PDU_GET);
@@ -520,12 +542,12 @@ request_other_dispatch (struct request* req, struct snmp_pdu* pdu)
ASSERT (req->pdu.nbindings == 1);
if (req->callbacks[0].func)
- (req->callbacks[0].func) (req->id, SNMP_ERR_NOERROR,
+ (req->callbacks[0].func) (MAKE_REQUEST_ID (req->snmp_id, 0), SNMP_ERR_NOERROR,
&(pdu->bindings[0]), req->callbacks[0].arg);
- log_debug ("request #%d is complete", req->id);
+ log_debug ("request #%d is complete", req->snmp_id);
- val = hsh_rem (snmp_processing, &req->id, sizeof (req->id));
+ val = hsh_rem (snmp_processing, &req->snmp_id, sizeof (req->snmp_id));
ASSERT (val == req);
request_release (req);
}
@@ -573,7 +595,7 @@ request_response (int fd, int type, void* arg)
id = pdu.request_id;
req = hsh_get (snmp_processing, &id, sizeof (id));
if(!req) {
- log_debug ("received extra or delayed packet from: %s", hostname);
+ log_debug ("received extra, cancelled or delayed packet from: %s", hostname);
return;
}
@@ -583,7 +605,7 @@ request_response (int fd, int type, void* arg)
/* Log any errors */
if(pdu.error_status == SNMP_ERR_NOERROR) {
- log_debug ("response to request #%d from: %s", req->id, hostname);
+ log_debug ("response to request #%d from: %s", req->snmp_id, hostname);
if (req->pdu.type == SNMP_PDU_GET)
request_get_dispatch (req, &pdu);
@@ -593,9 +615,9 @@ request_response (int fd, int type, void* arg)
} else {
msg = snmp_get_errmsg (pdu.error_status);
if(msg)
- log_debug ("failure for request #%d from: %s: %s", req->id, hostname, msg);
+ log_debug ("failure for request #%d from: %s: %s", req->snmp_id, hostname, msg);
else
- log_debug ("failure for request #%d from: %s: %d", req->id, hostname,
+ log_debug ("failure for request #%d from: %s: %d", req->snmp_id, hostname,
pdu.error_status);
request_failure (req, pdu.error_status);
}
@@ -641,7 +663,7 @@ request_flush (struct request *req, mstime when)
ASSERT (req->host->prepared == req);
- val = hsh_rem (snmp_preparing, &req->id, sizeof (req->id));
+ val = hsh_rem (snmp_preparing, &req->snmp_id, sizeof (req->snmp_id));
ASSERT (val == req);
/* Don't let us add more onto this request via the host */
@@ -651,7 +673,7 @@ request_flush (struct request *req, mstime when)
/* Mark this packet to be sent now */
req->next_send = when;
- if (!hsh_set (snmp_processing, &req->id, sizeof (req->id), req)) {
+ if (!hsh_set (snmp_processing, &req->snmp_id, sizeof (req->snmp_id), req)) {
log_errorx ("out of memory, discarding packets");
request_release (req);
}
@@ -698,7 +720,7 @@ request_prep_instance (struct host *host, mstime interval, mstime timeout, int r
/* See if we have one we can piggy back onto */
req = host->prepared;
if (req) {
- ASSERT (hsh_get (snmp_preparing, &req->id, sizeof (req->id)));
+ ASSERT (hsh_get (snmp_preparing, &req->snmp_id, sizeof (req->snmp_id)));
/* We have one we can piggy back another request onto */
if (req->pdu.nbindings < SNMP_MAX_BINDINGS && req->pdu.type == reqtype)
@@ -719,10 +741,14 @@ request_prep_instance (struct host *host, mstime interval, mstime timeout, int r
}
/* Assign the unique id */
- req->id = snmp_request_id++;
+ req->snmp_id = snmp_request_id++;
+
+ /* Roll around after a decent amount of ids */
+ if (snmp_request_id >= 0xFFFFFF)
+ snmp_request_id = 1;
/* Mark it down as something we want to prepare */
- if (!hsh_set (snmp_preparing, &req->id, sizeof (req->id), req)) {
+ if (!hsh_set (snmp_preparing, &req->snmp_id, sizeof (req->snmp_id), req)) {
log_error ("out of memory");
free (req);
return NULL;
@@ -730,7 +756,7 @@ request_prep_instance (struct host *host, mstime interval, mstime timeout, int r
/* Setup the packet */
strlcpy (req->pdu.community, host->community, sizeof (req->pdu.community));
- req->pdu.request_id = req->id;
+ req->pdu.request_id = req->snmp_id;
req->pdu.version = host->version;
req->pdu.type = reqtype;
req->pdu.error_status = 0;
@@ -749,7 +775,7 @@ request_prep_instance (struct host *host, mstime interval, mstime timeout, int r
ASSERT (host->prepared == NULL);
host->prepared = req;
- log_debug ("preparing request #%d for: %s@%s", req->id,
+ log_debug ("preparing request #%d for: %s@%s", req->snmp_id,
req->host->community, req->host->hostname);
return req;
@@ -762,6 +788,9 @@ snmp_engine_request (const char *hostname, const char *community, int version,
{
struct host *host;
struct request *req;
+ int callback_id;
+
+ ASSERT (func);
/* Lookup host for request */
host = host_instance (hostname, community, version, interval);
@@ -776,10 +805,11 @@ snmp_engine_request (const char *hostname, const char *community, int version,
ASSERT (req->pdu.nbindings < SNMP_MAX_BINDINGS);
/* Add the oid to that request */
- req->pdu.bindings[req->pdu.nbindings].var = *oid;
- req->pdu.bindings[req->pdu.nbindings].syntax = SNMP_SYNTAX_NULL;
- req->callbacks[req->pdu.nbindings].func = func;
- req->callbacks[req->pdu.nbindings].arg = arg;
+ callback_id = req->pdu.nbindings;
+ req->pdu.bindings[callback_id].var = *oid;
+ req->pdu.bindings[callback_id].syntax = SNMP_SYNTAX_NULL;
+ req->callbacks[callback_id].func = func;
+ req->callbacks[callback_id].arg = arg;
req->pdu.nbindings++;
/* All other than GET, only get one binding */
@@ -788,39 +818,62 @@ snmp_engine_request (const char *hostname, const char *community, int version,
request_flush (req, server_get_time ());
}
- if (!snmp_flush_pending) {
+ /* Otherwise flush on the idle callback */
+ else if (!snmp_flush_pending) {
server_oneshot (0, request_flush_cb, NULL);
snmp_flush_pending = 1;
}
- return req->id;
+ return MAKE_REQUEST_ID (req->snmp_id, callback_id);
}
void
-snmp_engine_cancel (int reqid)
+snmp_engine_cancel (int id)
{
struct request *req;
+ int snmp_id, callback_id, i;
+ const char *during;
+
+ ASSERT (id);
+
+ snmp_id = REQUEST_ID_SNMP (id);
+ callback_id = REQUEST_ID_CB (id);
+
+ ASSERT (snmp_id > 0 && snmp_id < 0xFFFFFF);
+ ASSERT (callback_id >= 0 && callback_id < SNMP_MAX_BINDINGS);
/* Is it being processed? */
- req = hsh_rem (snmp_processing, &reqid, sizeof (reqid));
+ req = hsh_rem (snmp_processing, &snmp_id, sizeof (snmp_id));
if (req) {
- log_debug ("cancelling request #%d during processing", reqid);
- request_release (req);
- return;
- }
+ during = "processing";
/* Is it being prepared? */
- req = hsh_rem (snmp_preparing, &reqid, sizeof (reqid));
- if (req) {
-
- /* Remove it from the host in question */
- ASSERT (req->host->prepared == req);
- req->host->prepared = NULL;
+ } else {
+ req = hsh_rem (snmp_preparing, &snmp_id, sizeof (snmp_id));
+ if (req) {
+ during = "prep";
+ ASSERT (req->host->prepared == req);
+ }
+ }
- log_debug ("cancelling request #%d during prep", reqid);
- request_release (req);
+ if (!req)
return;
+
+ /* Remove this callback from the request */
+ req->callbacks[callback_id].func = NULL;
+ req->callbacks[callback_id].arg = NULL;
+
+ /* See if any callbacks exist in the request */
+ for (i = 0; i < SNMP_MAX_BINDINGS; ++i) {
+ if (req->callbacks[i].func)
+ return;
}
+
+ /* If not, free the request */
+ log_debug ("cancelling request #%d during %s", snmp_id, during);
+ if (req->host->prepared == req)
+ req->host->prepared = NULL;
+ request_release (req);
}
void
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-18 18:14:19 +0000