SNMP frontend: Reworked types for GET types translation

YANG enum type, split up enum to int into two functions

apps/snmp/snmp_handler.c

@@ -126,54 +126,69 @@ snmp_scalar_get(clicon_handle               h,
 		yang_stmt                  *ys,
 		netsnmp_variable_list      *requestvb,
 		char                       *defaultval,
-		enum cv_type                cvtype,
 		netsnmp_agent_request_info *reqinfo,
 		netsnmp_request_info       *requests)
 {
-    int    retval = -1;
+    int     retval = -1;
-    cvec  *nsc = NULL;
+    cvec   *nsc = NULL;
-    char  *xpath = NULL;
+    char   *xpath = NULL;
-    cxobj *xt = NULL;
+    cxobj  *xt = NULL;
-    cxobj *xerr;
+    cxobj  *xerr;
-    cxobj *x;
+    cxobj  *x;
-    char  *valstr = NULL;
+    char   *snmpstr = NULL;
     u_char *snmpval = NULL;
-    size_t  snmplen;
+    size_t  snmplen = 0;
-    int    ret;
+    int     ret;
+    int     asn1type;
+    char   *reason = NULL;
 
+    /* Prepare backend call by constructing namespace context */
     if (xml_nsctx_yang(ys, &nsc) < 0)
 	goto done;
+    /* Create xpath from yang (XXX works not for lists) */
     if (yang2xpath(ys, &xpath) < 0)
 	goto done;
+    /* Do the backend call */
     if (clicon_rpc_get(h, xpath, nsc, CONTENT_ALL, -1, &xt) < 0)
 	goto done;
+    /* Detect error XXX Error handling could improve */
     if ((xerr = xpath_first(xt, NULL, "/rpc-error")) != NULL){
 	clixon_netconf_error(xerr, "clicon_rpc_get", NULL);
 	goto done;
     }
-    /* Get value, either from xml, or smiv2 default */
+    /* 
-    if ((x = xpath_first(xt, nsc, "%s", xpath)) != NULL) {
+     * The xml to snmp value conversion is done here. It is done in two steps:
-	valstr = xml_body(x);
+     * 1. From XML to SNMP string, there is a special case for enumeration, and for default value
+     * 2. From SNMP string to SNMP binary value which invloves parsing
+     */
+    if ((x = xpath_first(xt, nsc, "%s", xpath)) != NULL){
+	assert(xml_spec(x) == ys);
+	if (type_xml2snmpstr(xml_body(x), ys, &snmpstr) < 0)
+	    goto done;
+    }
+    else if (defaultval != NULL){
+	if ((snmpstr = strdup(defaultval)) == NULL){
+	    clicon_err(OE_UNIX, errno, "strdup");
+	    goto done;
+	}
     }
-    else if ((valstr = defaultval) != NULL)
-	;
     else{
 	netsnmp_set_request_error(reqinfo, requests, SNMP_NOSUCHINSTANCE);
 	goto ok;
     }
-    if ((ret = type_yang2snmp(valstr, cvtype, reqinfo, requests, &snmpval, &snmplen)) < 0)
+    if (type_yang2asn1(ys, &asn1type) < 0)
 	goto done;
-    if (ret == 0)
-	goto ok;
 
-    /* 1. use cligen object and get rwa buf / size from that, OR
+    if ((ret = type_snmpstr2val(snmpstr, asn1type, &snmpval, &snmplen, &reason)) < 0)
-     *    + have parse function from YANG
+	goto done;
-     *    - does not have 
+    if (ret == 0){
-     * 2. use union netsnmp_vardata and pass that here?
+	clicon_debug(1, "%s %s", __FUNCTION__, reason);
-     * 3. Make cv2asn1 conversion function <--
+	netsnmp_set_request_error(reqinfo, requests, SNMP_ERR_WRONGTYPE);
+	goto ok;
+    }
+    /* see snmplib/snmp_client. somewhat indirect
      */
-	
+    requestvb->type = asn1type; // ASN_NULL on input
-    /* see snmplib/snmp_client.c */
     if (snmp_set_var_value(requestvb,
 			   snmpval,
 			   snmplen) != 0){
@@ -183,6 +198,10 @@ snmp_scalar_get(clicon_handle               h,
  ok:
     retval = 0;
  done:
+    if (reason)
+	free(reason);
+    if (snmpstr)
+	free(snmpstr);
     if (snmpval)
 	free(snmpval);
     if (xt)
@@ -230,7 +249,7 @@ snmp_scalar_set(clicon_handle               h,
     }
     if ((xb = xml_new("body", xbot, CX_BODY)) == NULL)
 	goto done; 
-    if ((ret = type_snmp2yang(requestvb, reqinfo, requests, &valstr)) < 0)
+    if ((ret = type_snmp2xml(requestvb, reqinfo, requests, &valstr)) < 0)
 	goto done;
     if (ret == 0)
 	goto ok;
@@ -273,7 +292,6 @@ snmp_scalar_handler(netsnmp_mib_handler          *handler,
     yang_stmt             *ys;
     int                    asn1_type;
     netsnmp_variable_list *requestvb; /* sub of requests */
-    enum cv_type           cvtype;
     
     /*
      * can be used to pass information on a per-pdu basis from a
@@ -312,20 +330,19 @@ snmp_scalar_handler(netsnmp_mib_handler          *handler,
 			      SNMP_NOSUCHOBJECT);
     return SNMP_ERR_NOERROR;
 #endif
-    if (yang2snmp_types(ys, &asn1_type, &cvtype) < 0)
-	goto done;
-
     /* see net-snmp/agent/snmp_agent.h / net-snmp/library/snmp.h */
     switch (reqinfo->mode) {
     case MODE_GET:          /* 160 */
-	requestvb->type = asn1_type; // ASN_NULL on input
+	if (snmp_scalar_get(sh->sh_h, ys, requestvb, sh->sh_default, reqinfo, requests) < 0)
-	if (snmp_scalar_get(sh->sh_h, ys, requestvb, sh->sh_default, cvtype, reqinfo, requests) < 0)
 	    goto done;
         break;
     case MODE_GETNEXT:      /* 161 */
 	assert(0); // Not seen?
 	break;
     case MODE_SET_RESERVE1: /* 0 */
+	/* Translate from YANG ys leaf type to SNMP asn1.1 type ids (not value), also cvtype */
+	if (type_yang2asn1(ys, &asn1_type) < 0)
+	    goto done;
         if (requestvb->type != asn1_type)
             netsnmp_set_request_error(reqinfo, requests,
                                       SNMP_ERR_WRONGTYPE);

apps/snmp/snmp_lib.c

@@ -96,17 +96,12 @@ static const map_str2int snmp_access_map[] = {
  * XXX TimeTicks
  */
 static const map_str2int snmp_type_map[] = {
-
+    {"int32",        ASN_INTEGER},   // 2
-    {"int32",        ASN_INTEGER},
+    {"string",       ASN_OCTET_STR}, // 4
-    {"string",       ASN_OCTET_STR},
+    {"enumeration",  ASN_INTEGER},   // 2 special case
-    {"uint32",       ASN_INTEGER},
+    {"uint32",       ASN_GAUGE},     // 0x42 
-    {"uint64",       ASN_INTEGER},
+    {"uint64",       ASN_COUNTER64}, // 0x46 / 70
-    //  {"bool",         ASN_BOOLEAN},
+    {"boolean",      ASN_INTEGER},   // 2 special case -> enumeration
-    //  {"empty",        ASN_NULL},
-    //  {"bits",         ASN_BIT_STR},
-    //  {"", ASN_OBJECT_ID},
-    //  {"", ASN_SEQUENCE},
-    //  {"", ASN_SET},
     {NULL,           -1}
 };
 
@@ -136,18 +131,18 @@ snmp_msg_int2str(int msg)
 {
     return clicon_int2str(snmp_msg_map, msg);
 }
+
 /*! Translate from YANG to SNMP asn1.1 type ids (not value)
  *
  * @param[in]    ys         YANG leaf node
  * @param[out]   asn1_type  ASN.1 type id
- * @param[out]   cvtype     Clixon cv type
  * @retval   0   OK
  * @retval   -1  Error
+ * @see type_yang2snmp, yang only
  */
 int
-yang2snmp_types(yang_stmt    *ys,
+type_yang2asn1(yang_stmt    *ys,
-		int          *asn1_type,
+	       int          *asn1_type)
-		enum cv_type *cvtype)
 {
     int        retval = -1;
     yang_stmt *yrestype;  /* resolved type */
@@ -163,18 +158,17 @@ yang2snmp_types(yang_stmt    *ys,
     if ((at = clicon_str2int(snmp_type_map, restype)) < 0){
 	clicon_err(OE_YANG, 0, "No snmp translation for YANG %s type:%s",
 		   yang_argument_get(ys), restype);
-	//	goto done;
+	goto done;
     }
     if (asn1_type)
 	*asn1_type = at;
-    if (cvtype && clicon_type2cv(origtype, restype, ys, cvtype) < 0)
-	goto done;
     clicon_debug(1, "%s type:%s", __FUNCTION__, restype);
     retval = 0;
  done:
     return retval;
 }
 
+#if 0
 /*! Translate from yang/xml/clixon to SNMP/ASN.1
  *
  * @param[in]   valstr   Clixon/yang/xml string value
@@ -263,6 +257,8 @@ type_yang2snmp(char                       *valstr,
     retval = 0;
     goto done;
 }
+#endif
+
 /*! Translate from yang/xml/clixon to SNMP/ASN.1
  *
  * @param[in]   snmpval  Malloc:ed snmp type
@@ -275,10 +271,10 @@ type_yang2snmp(char                       *valstr,
  * @retval      -1       Error
  */
 int
-type_snmp2yang(netsnmp_variable_list      *requestvb,
+type_snmp2xml(netsnmp_variable_list      *requestvb,
-	       netsnmp_agent_request_info *reqinfo,
+	      netsnmp_agent_request_info *reqinfo,
-	       netsnmp_request_info       *requests,
+	      netsnmp_request_info       *requests,
-	       char                      **valstr)
+	      char                      **valstr)
 {
     int          retval = -1;
     char        *cvtypestr;
@@ -324,6 +320,146 @@ type_snmp2yang(netsnmp_variable_list      *requestvb,
     goto done;
 }
 
+/*! Given xml value and YANG,m return corresponding malloced snmp string
+ * There is a special case for enumeration which is integer in snmp, string in YANG
+ * @param[in]  xmlstr
+ */
+int
+type_xml2snmpstr(char      *xmlstr,
+		 yang_stmt *ys,
+		 char      **snmpstr)
+
+{
+    int        retval = -1;
+    yang_stmt *yrestype;  /* resolved type */
+    char      *restype;  /* resolved type */
+    char      *origtype=NULL;   /* original type */
+    char      *str = NULL;
+
+    if (snmpstr == NULL){
+	clicon_err(OE_UNIX, EINVAL, "snmpstr");
+	goto done;
+    }
+    /* 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;
+    if (strcmp(restype, "enumeration") == 0){ 	/* special case for enum */
+	if (yang_enum2intstr(yrestype, xmlstr, &str) < 0)
+	    goto done;
+    }
+    /* special case for bool: although smidump translates TruthValue to boolean
+     * and there is an ASN_BOOLEAN constant:
+     * 1) there is no code for ASN_BOOLEAN and
+     * 2) Truthvalue actually translates to enum true(1)/false(0)
+     */
+    else if (strcmp(restype, "boolean") == 0){ 	
+	if (strcmp(xmlstr, "false")==0)
+	    str = "0";
+	else
+	    str = "1";
+    }
+    else{
+	str = xmlstr;
+    }
+    if ((*snmpstr = strdup(str)) == NULL){
+	clicon_err(OE_UNIX, errno, "strdup");
+	goto done;
+    }
+    retval = 0;
+ done:
+    clicon_debug(1, "%s %d", __FUNCTION__, retval);
+    return retval;
+}
+
+/*! Given snmp string value (as translated frm XML) parse into snmp value
+ *
+ * @param[in]  snmpstr  SNMP type string
+ * @param[in]  asn1type ASN.1 type id
+ * @param[out] snmpval  Malloc:ed snmp type
+ * @param[out] snmplen  Length of snmp type
+ * @param[out] reason   Error reason if retval is 0
+ * @retval     1        OK
+ * @retval     0        Invalid
+ * @retval     -1       Error
+ */
+int
+type_snmpstr2val(char       *snmpstr,
+		 int         asn1type,
+		 u_char    **snmpval,
+		 size_t     *snmplen,
+		 char      **reason)
+{
+    int   retval = -1;
+    int   ret;
+
+    if (snmpval == NULL || snmplen == NULL){
+	clicon_err(OE_UNIX, EINVAL, "snmpval or snmplen is NULL");
+	goto done;
+    }
+    switch (asn1type){
+    case ASN_BOOLEAN:   // 1
+	break;
+    case ASN_INTEGER:   // 2
+	*snmplen = 4;
+	if ((*snmpval = malloc(*snmplen)) == NULL){
+	    clicon_err(OE_UNIX, errno, "malloc");
+	    goto done;
+	}
+	if ((ret = parse_int32(snmpstr, (int32_t*)*snmpval, reason)) < 0)
+	    goto done;
+	if (ret == 0)
+	    goto fail;
+	break;
+    case ASN_GAUGE:   // 0x42
+	*snmplen = 4;
+	if ((*snmpval = malloc(*snmplen)) == NULL){
+	    clicon_err(OE_UNIX, errno, "malloc");
+	    goto done;
+	}
+	if ((ret = parse_uint32(snmpstr, (uint32_t*)*snmpval, reason)) < 0)
+	    goto done;
+	if (ret == 0)
+	    goto fail;
+
+	break;
+    case ASN_OCTET_STR: // 4
+	*snmplen = strlen(snmpstr)+1;
+	if ((*snmpval = (u_char*)strdup((snmpstr))) == NULL){
+	    clicon_err(OE_UNIX, errno, "strdup");
+	    goto done;
+	}
+	break;
+    case ASN_COUNTER64:{ // 0x46 / 70
+	uint64_t u64;
+	struct counter64 *c64;
+	*snmplen = sizeof(struct counter64); // 16!
+	if ((*snmpval = malloc(*snmplen)) == NULL){
+	    clicon_err(OE_UNIX, errno, "malloc");
+	    goto done;
+	}
+	memset(*snmpval, 0, *snmplen);
+	if ((ret = parse_uint64(snmpstr, &u64, reason)) < 0)
+	    goto done;
+	c64 = (struct counter64 *)*snmpval;
+	c64->low = u64&0xffffffff;
+	c64->high = u64/0x100000000;
+	if (ret == 0)
+	    goto fail;
+    }
+	break;
+    default:
+	assert(0);
+    }
+    retval = 1;
+ done:
+    clicon_debug(1, "%s %d", __FUNCTION__, retval);
+    return retval;
+ fail:
+    retval = 0;
+    goto done;
+}
+
 /*! Construct an xpath from yang statement, internal fn using cb
  * Recursively construct it to the top.
  * @param[in]  ys    Yang statement

apps/snmp/snmp_lib.h

@@ -60,14 +60,14 @@ typedef struct clixon_snmp_handle clixon_snmp_handle;
  */
 int   snmp_access_str2int(char *modes_str);
 const char *snmp_msg_int2str(int msg);
-int   yang2snmp_types(yang_stmt *ys, int *asn1_type, enum cv_type *cvtype);
+int   type_yang2asn1(yang_stmt *ys, int *asn1_type);
-int   type_yang2snmp(char *valstr, enum cv_type cvtype,
+int   type_snmp2xml(netsnmp_variable_list      *requestvb,
-		     netsnmp_agent_request_info *reqinfo, netsnmp_request_info *requests,
+		    netsnmp_agent_request_info *reqinfo,
-		     u_char **snmpval, size_t *snmplen);
+		    netsnmp_request_info       *requests,
-int   type_snmp2yang(netsnmp_variable_list      *requestvb,
+		    char                      **valstr);
-		     netsnmp_agent_request_info *reqinfo,
+int   type_xml2snmpstr(char *xmlstr, yang_stmt *ys, char **snmpstr);
-		     netsnmp_request_info       *requests,
+
-		     char                      **valstr);
+int   type_snmpstr2val(char *snmpstr, int asn1type, u_char **snmpval, size_t *snmplen, char **reason);
 int   yang2xpath(yang_stmt *ys, char **xpath);
 int   clixon_table_create(netsnmp_table_data_set *table, yang_stmt *ys, clicon_handle h);
 

apps/snmp/snmp_register.c

@@ -205,8 +205,8 @@ mib_yang_leaf(clicon_handle h,
     }
     if (yang_extension_value(ys, "max-access", IETF_YANG_SMIV2_NS, NULL, &modes_str) < 0)
 	goto done;
-#if 0 /* Sanity check of types */
+#if 1 /* Sanity check of types */
-    if (yang2snmp_types(ys, NULL, NULL) < 0)
+    if (type_yang2asn1(ys, NULL) < 0)
 	goto done;
 #endif
     /* Get modes (access) read-only, read-write, not-accessible, oaccessible-for-notify

lib/clixon/clixon_xml_map.h

@@ -72,6 +72,7 @@ int xml2xpath(cxobj *x, cvec *nsc, char **xpath);
 int assign_namespace_element(cxobj *x0, cxobj *x1, cxobj *x1p);
 int assign_namespace_body(cxobj *x0, cxobj *x1);
 int xml_merge(cxobj *x0, cxobj *x1, yang_stmt *yspec, char **reason);
+int yang_enum2intstr(yang_stmt *ytype, char *value, char **intstr);
 int yang_enum_int_value(cxobj *node, int32_t *val);
 int xml_copy_marked(cxobj *x0, cxobj *x1);
 int yang_check_when_xpath(cxobj *xn, cxobj *xp, yang_stmt *yn, int *hit, int *nrp, char **xpathp);

lib/src/clixon_xml_map.c

@@ -1922,6 +1922,37 @@ xml_merge(cxobj     *x0,
     goto done;
 }
 
+
+/*! Given a YANG (enum) type node and a value, return the string containing corresponding int str
+ *
+ * @param[in]  ytype   YANG type noden
+ * @param[in]  valstr  Value of enum
+ * @param[out] intstr  Corresponding string containing an int (direct pointer, dont free)
+ */
+int
+yang_enum2intstr(yang_stmt *ytype,
+		 char      *valstr,
+		 char     **intstr)
+{
+    int        retval = -1;
+    yang_stmt *yenum; 
+    yang_stmt *yval; 
+
+    if (intstr == NULL){
+	clicon_err(OE_UNIX, EINVAL, "intstr is NULL");
+	goto done;
+    }
+    if ((yenum = yang_find(ytype, Y_ENUM, valstr)) == NULL)
+	goto done;
+    /* Should assign value if yval not found */
+    if ((yval = yang_find(yenum, Y_VALUE, NULL)) == NULL)
+	goto done;
+    *intstr = yang_argument_get(yval);
+    retval = 0;
+ done:
+    return retval;
+}
+
 /*! Get integer value from xml node from yang enumeration 
  * @param[in]  node XML node in a tree
  * @param[out] val  Integer value returned
@@ -1944,9 +1975,8 @@ yang_enum_int_value(cxobj   *node,
     yang_stmt *ys;
     yang_stmt *ytype;
     yang_stmt *yrestype;  /* resolved type */
-    yang_stmt *yenum; 
-    yang_stmt *yval; 
     char      *reason = NULL;
+    char      *intstr = NULL;
 
     if (node == NULL)
 	goto done;
@@ -1965,20 +1995,16 @@ yang_enum_int_value(cxobj   *node,
     }
     if (yrestype==NULL || strcmp(yang_argument_get(yrestype), "enumeration"))
 	goto done;
-    if ((yenum = yang_find(yrestype, Y_ENUM, xml_body(node))) == NULL)
+    if (yang_enum2intstr(yrestype, xml_body(node), &intstr) < 0)
-	goto done;
-    /* Should assign value if yval not found */
-    if ((yval = yang_find(yenum, Y_VALUE, NULL)) == NULL)
 	goto done;
     /* reason is string containing why int could not be parsed */
-    if (parse_int32(yang_argument_get(yval), val, &reason) < 0)
+    if (parse_int32(intstr, val, &reason) < 0)
 	goto done;
     retval = 0;
 done:
     return retval;
 }
 
-
 /*! Given XML tree x0 with marked nodes, copy marked nodes to new tree x1
  * Two marks are used: XML_FLAG_MARK and XML_FLAG_CHANGE
  *