SNMP frontend, RPC of single variable through clixon

This commit is contained in:
Olof hagsand 2022-05-06 14:48:52 +02:00
parent 4e0d9dd987
commit 182b72a4cc
4 changed files with 258 additions and 58 deletions

View file

@ -30,6 +30,7 @@
the terms of any one of the Apache License version 2 or the GPL.
***** END LICENSE BLOCK *****
* See RFC 6643
* Extensions are grouped in some categories, the one I have seen are, example:
* 1. leaf
* smiv2:max-access "read-write";
@ -71,6 +72,18 @@
#define IETF_YANG_SMIV2_NS "urn:ietf:params:xml:ns:yang:ietf-yang-smiv2"
/*
* Local Types
*/
/* Userdata to pass around in netsmp callbacks
*/
struct clixon_snmp_handle {
clicon_handle sh_h;
yang_stmt *sh_ys;
int sh_type; /* ASN.1 type */
};
typedef struct clixon_snmp_handle clixon_snmp_handle;
/*
* Local variables
*/
@ -81,12 +94,28 @@
* Here is also the place where doc on some types store variables (cv)
* see netsnmp_handler_registration_create()
*/
static const map_str2int acc_map[] = {
static const map_str2int snmp_access_map[] = {
{"read-only", HANDLER_CAN_RONLY}, /* HANDLER_CAN_GETANDGETNEXT */
{"read-write", HANDLER_CAN_RWRITE}, /* HANDLER_CAN_GETANDGETNEXT | HANDLER_CAN_SET */
{"not-accessible", 0}, // XXX
{"accessible-for-notify", 0}, // XXX
{NULL, -1}
{NULL, -1}
};
/* Map between clixon and ASN.1 types.
* @see net-snmp/library/asn1.h
* @see union netsnmp_vardata in net-snmp/types.h
*/
static const map_str2int snmp_type_map[] = {
{"bool", ASN_BOOLEAN},
{"int32", ASN_INTEGER},
{"bits", ASN_BIT_STR},
{"string", ASN_OCTET_STR},
{"empty", ASN_NULL},
//XXX {"", ASN_OBJECT_ID},
// XXX {"", ASN_SEQUENCE},
// XXX {"", ASN_SET},
{NULL, -1}
};
#if 1 /* table example */
@ -223,78 +252,223 @@ init_testtable(void)
}
#endif /* table example */
#if 1 /* scalar example */
#define TESTHANDLER_SET_NAME "my_test"
int
my_test_instance_handler(netsnmp_mib_handler *handler,
netsnmp_handler_registration *reginfo,
netsnmp_agent_request_info *reqinfo,
netsnmp_request_info *requests)
/*! Construct an xpath from yang statement
* Recursively construct it to the top.
* @param[in] ys Yang statement
* @param[out] cb xpath as cbuf
* @retval 0 OK
* @retval -1 Error
* XXX Not lists
*/
static int
yang2xpath(yang_stmt *ys,
cbuf *cb)
{
yang_stmt *yp; /* parent */
int i;
cvec *cvk = NULL; /* vector of index keys */
int retval = -1;
if ((yp = yang_parent_get(ys)) == NULL){
clicon_err(OE_YANG, EINVAL, "yang expected parent %s", yang_argument_get(ys));
goto done;
}
if (yp != NULL && /* XXX rm */
yang_keyword_get(yp) != Y_MODULE &&
yang_keyword_get(yp) != Y_SUBMODULE){
static int accesses = 42;
u_long *accesses_cache = NULL;
// clicon_handle h = (clicon_handle)handler->myvoid;
if (yang2xpath(yp, cb) < 0) /* recursive call */
goto done;
if (yang_keyword_get(yp) != Y_CHOICE && yang_keyword_get(yp) != Y_CASE){
cprintf(cb, "/");
}
}
cprintf(cb, "/%s:", yang_find_myprefix(ys));
if (yang_keyword_get(ys) != Y_CHOICE && yang_keyword_get(ys) != Y_CASE)
cprintf(cb, "%s", yang_argument_get(ys));
switch (yang_keyword_get(ys)){
case Y_LIST: // XXX not xpaths
cvk = yang_cvec_get(ys); /* Use Y_LIST cache, see ys_populate_list() */
if (cvec_len(cvk))
cprintf(cb, "=");
/* Iterate over individual keys */
for (i=0; i<cvec_len(cvk); i++){
if (i)
cprintf(cb, ",");
cprintf(cb, "%%s");
}
break;
case Y_LEAF_LIST:
cprintf(cb, "=%%s");
break;
default:
break;
} /* switch */
retval = 0;
done:
return retval;
}
/*! SNMP Scalar operation handler
* Calls come: READ:160,
* WRITE: 0, 1, 2, 3,
* MODE_SET_RESEVE1, MODE_SET_RESERVE2, MODE_SET_ACTION, MODE_SET_COMMIT
*
*/
int
snmp_scalar_handler(netsnmp_mib_handler *handler,
netsnmp_handler_registration *reginfo,
netsnmp_agent_request_info *reqinfo,
netsnmp_request_info *requests)
{
int retval = -1;
clixon_snmp_handle *sh;
int accesses;
// u_long *accesses_cache = NULL;
yang_stmt *ys;
clicon_handle h;
cbuf *cb = NULL;
int ret;
/*
* can be used to pass information on a per-pdu basis from a
* helper to the later handlers
netsnmp_agent_request_info *reqinfo,
netsnmp_data_list *agent_data;
netsnmp_free_agent_data_set()
*/
clicon_debug(1, "%s", __FUNCTION__);
clicon_debug(1, "%s %p", __FUNCTION__, reginfo);
sh = (clixon_snmp_handle*)handler->myvoid;
ys = sh->sh_ys;
h = sh->sh_h;
clicon_debug(1, "%s mode:%d", __FUNCTION__, reqinfo->mode);
/* see net-snmp/agent/snmp_agent.h / net-snmp/library/snmp.h */
switch (reqinfo->mode) {
case MODE_GET:
snmp_set_var_typed_value(requests->requestvb, ASN_INTEGER,
(u_char *) & accesses, sizeof(accesses));
case MODE_GET: // 160
requests->requestvb->type = sh->sh_type; // ASN_NULL on input
/* get xpath: see yang2api_path_fmt / api_path2xpath
New fn: yang2xpath?
clicon_rpc_get()
<rpc $DEFAULTNS><get><filter type=\"xpath\" select=\"/if:interfaces\" xmlns:if=\"urn:ietf:params:xml:ns:yang:ietf-interfaces\" /></get></rpc>"
*/
cxobj *xt = NULL;
cxobj *xerr;
cvec *nsc = NULL;
cxobj *x;
char *xpath;
cg_var *cv = NULL;
char *reason = NULL;
if (xml_nsctx_yang(ys, &nsc) < 0)
goto done;
if ((cb = cbuf_new()) == NULL){
clicon_err(OE_UNIX, errno, "cbuf_new");
goto done;
}
if (yang2xpath(ys, cb) < 0)
goto done;
xpath = cbuf_get(cb);
if (clicon_rpc_get(h, xpath, nsc, CONTENT_ALL, -1, &xt) < 0)
goto done;
if ((xerr = xpath_first(xt, NULL, "/rpc-error")) != NULL){
clixon_netconf_error(xerr, "clicon_rpc_get", NULL);
goto done;
}
if ((x = xpath_first(xt, nsc, "%s", xpath)) < 0)
goto done;
xml_body(x);
if ((cv = cv_new(CGV_INT32)) == NULL){
clicon_err(OE_UNIX, errno, "cv_new");
goto done;
}
if ((ret = cv_parse1(xml_body(x), cv, &reason)) < 0){
cv_free(cv);
goto done;
}
if (ret == 0){
clicon_debug(1, "%s %s", __FUNCTION__, reason);
netsnmp_set_request_error(reqinfo, requests,
SNMP_ERR_WRONGTYPE);
}
accesses = cv_int32_get(cv); // XXX Use cv type space
if (reason)
free(reason);
if (xt)
xml_free(xt);
if (nsc)
xml_nsctx_free(nsc);
/* 1. use cligen object and get rwa buf / size from that, OR
* + have parse function from YANG
* - does not have
* 2. use union netsnmp_vardata and pass that here?
* 3. Make cv2asn1 conversion function <--
*/
/* see snmplib/snmp_client.c */
if (snmp_set_var_value(requests->requestvb,
(u_char *) & accesses,
sizeof(accesses)) != 0){
clicon_err(OE_SNMP, 0, "snmp_set_var_value");
goto done;
}
break;
case MODE_SET_RESERVE1:
if (requests->requestvb->type != ASN_INTEGER)
case MODE_SET_RESERVE1: // 0
if (requests->requestvb->type != sh->sh_type)
netsnmp_set_request_error(reqinfo, requests,
SNMP_ERR_WRONGTYPE);
break;
case MODE_SET_RESERVE2:
/*
* store old info for undo later
*/
accesses_cache = netsnmp_memdup(&accesses, sizeof(accesses));
if (accesses_cache == NULL) {
netsnmp_set_request_error(reqinfo, requests,
SNMP_ERR_RESOURCEUNAVAILABLE);
return SNMP_ERR_NOERROR;
}
netsnmp_request_add_list_data(requests,
netsnmp_create_data_list
(TESTHANDLER_SET_NAME,
accesses_cache, free));
case MODE_SET_RESERVE2: // 1
break;
case MODE_SET_ACTION:
case MODE_SET_ACTION: // 2
/*
* update current
*/
accesses = *(requests->requestvb->val.integer);
DEBUGMSGTL(("testhandler", "updated accesses -> %d\n", accesses));
/* yang2xpath -> xpath2xml
* accesses = *(requests->requestvb->val.integer);
* rpc edit-config
<data></data>
*/
if ((cb = cbuf_new()) == NULL){
clicon_err(OE_UNIX, errno, "cbuf_new");
goto done;
}
cprintf(cb, "<config><NET-SNMP-EXAMPLES-MIB xmlns=\"urn:ietf:params:xml:ns:yang:smiv2:NET-SNMP-EXAMPLES-MIB\"><netSnmpExampleScalars><netSnmpExampleInteger>%ld</netSnmpExampleInteger></netSnmpExampleScalars></NET-SNMP-EXAMPLES-MIB></config>", *requests->requestvb->val.integer);
if (clicon_rpc_edit_config(h, "candidate", OP_MERGE, cbuf_get(cb)) < 0)
goto done;
break;
case MODE_SET_UNDO:
accesses =
*((u_long *) netsnmp_request_get_list_data(requests,
TESTHANDLER_SET_NAME));
case MODE_SET_UNDO: // 5
if (clicon_rpc_discard_changes(h) < 0)
goto done;
break;
case MODE_SET_COMMIT:
case MODE_SET_FREE:
case MODE_SET_COMMIT: // 3
if (clicon_rpc_commit(h) < 0)
goto done;
break;
case MODE_SET_FREE: // 4
/*
* nothing to do
*/
break;
}
return SNMP_ERR_NOERROR;
retval = SNMP_ERR_NOERROR;
done:
if (cb)
cbuf_free(cb);
return retval;
}
#endif
/*! Parse smiv2 extensions for YANG leaf
* Typical leaf:
* smiv2:oid "1.3.6.1.4.1.8072.2.1.1";
@ -315,9 +489,12 @@ mib_yang_leaf(clicon_handle h,
size_t sz1 = MAX_OID_LEN;
int modes;
yang_stmt *yrestype; /* resolved type */
// char *restype; /* resolved type */
char *restype; /* resolved type */
char *origtype=NULL; /* original type */
int asn1_type;
char *name;
clixon_snmp_handle *sh;
if (yang_extension_value(ys, "oid", IETF_YANG_SMIV2_NS, NULL, &oidstr) < 0)
goto done;
@ -330,30 +507,42 @@ mib_yang_leaf(clicon_handle h,
if (yang_extension_value(ys, "max-access", IETF_YANG_SMIV2_NS, NULL, &modes_str) < 0)
goto done;
/* read-only, read-write, not-accessible, oaccessible-for-notify
/* Get modes (access) read-only, read-write, not-accessible, oaccessible-for-notify
*/
if (modes_str == NULL)
goto ok;
modes = clicon_str2int(acc_map, modes_str);
modes = clicon_str2int(snmp_access_map, modes_str);
/* Default value, XXX How is this different from yang defaults?
*/
// if (yang_extension_value(ys, "defval", IETF_YANG_SMIV2_NS, NULL, &modes_str) < 0)
// goto done;
/* get yang type of leaf */
/* Get yang type of leaf and trasnslate to ASN.1 */
if (yang_type_get(ys, &origtype, &yrestype, NULL, NULL, NULL, NULL, NULL) < 0)
goto done;
// restype = yrestype?yang_argument_get(yrestype):NULL;
restype = yrestype?yang_argument_get(yrestype):NULL;
/* translate to asn.1 */
asn1_type = clicon_str2int(snmp_type_map, restype);
name = yang_argument_get(ys);
if ((handler = netsnmp_create_handler(name, my_test_instance_handler)) == NULL){
if ((handler = netsnmp_create_handler(name, snmp_scalar_handler)) == NULL){
clicon_err(OE_SNMP, errno, "netsnmp_create_handler");
goto done;
}
// handler->myvoid = h;
handler->myvoid =(void*)99;
/* Userdata to pass around in netsmp callbacks
* XXX: not deallocated
*/
if ((sh = malloc(sizeof(*sh))) == NULL){
clicon_err(OE_UNIX, errno, "malloc");
goto done;
}
sh->sh_h = h;
sh->sh_ys = ys;
sh->sh_type = asn1_type;
handler->myvoid =(void*)sh;
if ((nh = netsnmp_handler_registration_create(name,
handler,
oid1,
@ -363,6 +552,9 @@ mib_yang_leaf(clicon_handle h,
netsnmp_handler_free(handler);
goto done;
}
/*
* XXX: nh->agent_data
*/
if ((ret = netsnmp_register_instance(nh)) < 0){
/* XXX Failures are MIB_REGISTRATION_FAILED and MIB_DUPLICATE_REGISTRATION. */
clicon_err(OE_SNMP, ret, "netsnmp_register_instance");

View file

@ -581,7 +581,7 @@ clicon_rpc_get_config(clicon_handle h,
* @note xml arg need to have <config> as top element
* @code
* if (clicon_rpc_edit_config(h, "running", OP_MERGE,
* "<config><a>4</a></config>") < 0)
* "<config><a xmlns="urn:example:clixon">4</a></config>") < 0)
* err;
* @endcode
*/

View file

@ -16,6 +16,7 @@ snmpset="$(type -p snmpset) -On -c public -v2c localhost "
cfg=$dir/conf_startup.xml
fyang=$dir/clixon-example.yang
fstate=$dir/state.xml
# AgentX unix socket
SOCK=/var/run/snmp.sock
@ -46,8 +47,15 @@ module clixon-example{
}
EOF
# This is state data written to file that backend reads from (on request)
cat <<EOF > $fstate
<sender-state xmlns="urn:example:example">
<ref>x</ref>
</sender-state>
EOF
function testinit(){
new "test params: -f $cfg"
new "test params: -f $cfg -- -sS $fstate"
if [ $BE -ne 0 ]; then
# Kill old backend and start a new one
@ -60,7 +68,7 @@ function testinit(){
sudo pkill -f clixon_backend
new "Starting backend"
start_backend -s init -f $cfg
start_backend -s init -f $cfg -- -sS $fstate
fi
new "wait backend"

View file

@ -41,7 +41,7 @@ cat <<EOF > $cfg
<CLICON_BACKEND_PIDFILE>/var/tmp/$APPNAME.pidfile</CLICON_BACKEND_PIDFILE>
<CLICON_XMLDB_DIR>$dir</CLICON_XMLDB_DIR>
<CLICON_SNMP_AGENT_SOCK>unix:$SOCK</CLICON_SNMP_AGENT_SOCK>
<CLICON_SNMP_MIB>NET-SNMP-EXAMPLES-MIB</CLICON_SNMP_MIB>
<!--CLICON_SNMP_MIB>NET-SNMP-EXAMPLES-MIB</CLICON_SNMP_MIB-->
</clixon-config>
EOF