Added intermediate pluggin extender (#1)

src/plugins/intermediate/CMakeLists.txt

@@ -1,3 +1,4 @@
 # List of output plugin to build and install
 add_subdirectory(anonymization)
-add_subdirectory(filter)
+add_subdirectory(filter)
+add_subdirectory(extender)

src/plugins/intermediate/extender/CMakeLists.txt

@@ -0,0 +1,28 @@
+add_library(extender-intermediate MODULE
+    msg_builder.h
+    extender.c
+    config.c
+    config.h
+)
+
+install(
+    TARGETS extender-intermediate
+    LIBRARY DESTINATION "${INSTALL_DIR_LIB}/ipfixcol2/"
+)
+
+if (ENABLE_DOC_MANPAGE)
+    # Build a manual page
+    set(SRC_FILE "${CMAKE_CURRENT_SOURCE_DIR}/doc/ipfixcol2-extender-inter.7.rst")
+    set(DST_FILE "${CMAKE_CURRENT_BINARY_DIR}/ipfixcol2-extender-inter.7")
+
+    add_custom_command(TARGET extender-intermediate PRE_BUILD
+        COMMAND ${RST2MAN_EXECUTABLE} --syntax-highlight=none ${SRC_FILE} ${DST_FILE}
+        DEPENDS ${SRC_FILE}
+        VERBATIM
+        )
+
+    install(
+        FILES "${DST_FILE}"
+        DESTINATION "${INSTALL_DIR_MAN}/man7"
+    )
+endif()

src/plugins/intermediate/extender/README.rst

@@ -0,0 +1,65 @@
+============================
+ Extender (intermediate plugin)
+============================
+
+This intermediate plugin extends IPFIX records by adding new items to the existing record set using user-defined expressions.
+
+
+Example configuration
+---------------------
+
+.. code-block:: xml
+
+    <intermediate>
+      <name>Extenders</name>
+      <plugin>extender</plugin>
+      <params>
+        <ids>          
+          <id>iana:VRFname</id>
+          <values>
+            <expr>iana:dot1qCustomerVlanId == 0</expr>
+            <value>vrf-0</value>
+          </values>
+          <values>
+            <expr>iana:dot1qCustomerVlanId == 1</expr>
+            <value>vrf-1</value>
+          </values>
+        </ids>
+      </params>
+    </intermediate>
+
+The above sample adds a new string field ``VRFname=vrf-0`` or ``VRFname=vrf-1`` to each IPFIX record depending on the value of ``dot1qCustomerVlanId``.
+
+Parameters
+----------
+
+``expr``
+    The filter expression to evaluate.
+
+``id``
+    The identifier string to be added to the record when the expression evaluates to true.
+
+
+Supported operations
+--------------------
+
+Comparisons
+    - Operators: ``==``, ``<``, ``>``, ``<=``, ``>=``, ``!=``
+    - Default: ``==`` (if the operator is omitted)
+
+Substring Matching
+    - Operator: ``contains``
+    - Example: ``DNSName contains "example"``
+
+Arithmetic
+    - Operators: ``+``, ``-``, ``*``, ``/``, ``%``
+
+Bitwise Logic
+    - Operators: ``~`` (not), ``|`` (or), ``&`` (and), ``^`` (xor)
+
+List Membership
+    - Operator: ``in``
+    - Example: ``port in [80, 443]``
+
+Logical Operators
+    - Operators: ``and``, ``or``, ``not``

src/plugins/intermediate/extender/config.c

@@ -0,0 +1,233 @@
+/**
+ * \file src/plugins/intermediate/filter/config.c
+ * \author Michal Sedlak <xsedla0v@stud.fit.vutbr.cz>
+ * \brief The filter plugin config
+ * \date 2020
+ */
+
+/* Copyright (C) 2020 CESNET, z.s.p.o.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name of the Company nor the names of its contributors
+ *    may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * ALTERNATIVELY, provided that this notice is retained in full, this
+ * product may be distributed under the terms of the GNU General Public
+ * License (GPL) version 2 or later, in which case the provisions
+ * of the GPL apply INSTEAD OF those given above.
+ *
+ * This software is provided ``as is'', and any express or implied
+ * warranties, including, but not limited to, the implied warranties of
+ * merchantability and fitness for a particular purpose are disclaimed.
+ * In no event shall the company or contributors be liable for any
+ * direct, indirect, incidental, special, exemplary, or consequential
+ * damages (including, but not limited to, procurement of substitute
+ * goods or services; loss of use, data, or profits; or business
+ * interruption) however caused and on 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 advised of the possibility of such damage.
+ *
+ */
+
+#include "config.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+/*
+ * <params>
+ *   <expr>...</expr>
+ * </params>
+ */
+
+enum params_xml_nodes {
+    EXTENSION_EXPR = 1,
+    EXTENSION_ID = 2,
+    EXTENSION_VALUES = 3,
+    EXTENSION_VALUE = 4,
+    EXTENSION_IDS = 5
+};
+
+static const struct fds_xml_args values_params[] = {
+    FDS_OPTS_ELEM(EXTENSION_EXPR, "expr", FDS_OPTS_T_STRING, 0),
+    FDS_OPTS_ELEM(EXTENSION_VALUE, "value", FDS_OPTS_T_STRING, 0),
+    FDS_OPTS_END
+};
+
+static const struct fds_xml_args ids_params[] = {
+    FDS_OPTS_ELEM(EXTENSION_ID, "id", FDS_OPTS_T_STRING, 0),    
+    FDS_OPTS_NESTED(EXTENSION_VALUES, "values", values_params, FDS_OPTS_P_OPT | FDS_OPTS_P_MULTI),
+    FDS_OPTS_END
+};
+
+static const struct fds_xml_args args_params[] = {
+    FDS_OPTS_ROOT("params"),
+    FDS_OPTS_NESTED(EXTENSION_IDS, "ids", ids_params, FDS_OPTS_P_OPT | FDS_OPTS_P_MULTI),
+    FDS_OPTS_END
+};
+
+int config_parse_values(ipx_ctx_t *ctx, const struct fds_xml_cont *content, config_ids_t* id) {
+    const struct fds_xml_cont *value_content;
+    while (fds_xml_next(content->ptr_ctx, &value_content) == FDS_OK) {
+        switch (value_content->id) {
+            case EXTENSION_VALUE:
+                assert(value_content->type == FDS_OPTS_T_STRING);
+                if (strlen(value_content->ptr_string) == 0) {
+                    IPX_CTX_ERROR(ctx, "Extension value is empty!");
+                    return -1;
+                }
+                id->values[id->values_count].value = strdup(value_content->ptr_string);
+                if (!id->values[id->values_count].value) {
+                    IPX_CTX_ERROR(ctx, "Memory allocation error (%s:%d)", __FILE__, __LINE__);
+                    return -1;
+                }
+                break;
+            case EXTENSION_EXPR:
+                assert(value_content->type == FDS_OPTS_T_STRING);
+                if (strlen(value_content->ptr_string) == 0) {
+                    IPX_CTX_ERROR(ctx, "Filter expression is empty!");
+                    return -1;
+                }
+                id->values[id->values_count].expr = strdup(value_content->ptr_string);
+                if (!id->values[id->values_count].expr) {
+                    IPX_CTX_ERROR(ctx, "Memory allocation error (%s:%d)", __FILE__, __LINE__);
+                    return -1;
+                }
+                break;
+            default:
+                break;
+        }
+    }
+    return 0;
+}
+
+int config_parse_ids(ipx_ctx_t *ctx, const struct fds_xml_cont *content, config_ids_t* id) {
+    const struct fds_xml_cont *id_content;
+    while (fds_xml_next(content->ptr_ctx, &id_content) == FDS_OK) {
+        switch (id_content->id) {
+            case EXTENSION_ID:
+                // Ignored in this plugin
+                assert(id_content->type == FDS_OPTS_T_STRING);
+                if (strlen(id_content->ptr_string) == 0) {
+                    IPX_CTX_ERROR(ctx, "Extension ID is empty!");
+                    return -1;
+                }
+                id->name = strdup(id_content->ptr_string);
+                if (!id->name) {
+                    IPX_CTX_ERROR(ctx, "Memory allocation error (%s:%d)", __FILE__, __LINE__);
+                    return -1;
+                }
+                break;
+            case EXTENSION_VALUES:
+                if( id->values_count >= CONFIG_VALUSE_MAX ) {
+                    IPX_CTX_ERROR(ctx, "Maximum number of extension values per id exceeded (%d)!", CONFIG_VALUSE_MAX);
+                    return -1;
+                }
+                config_parse_values(ctx, id_content, id);
+                id->values_count++;
+                break;
+            default:
+                break;
+        }
+    }
+    return 0;
+}
+
+struct config *
+config_parse(ipx_ctx_t *ctx, const char *params)
+{
+    struct config *cfg = NULL;
+    fds_xml_t *parser = NULL;
+
+    cfg = calloc(1, sizeof(struct config));
+    if (!cfg) {
+        IPX_CTX_ERROR(ctx, "Memory allocation error (%s:%d)", __FILE__, __LINE__);
+        goto error;
+    }
+
+    parser = fds_xml_create();
+    if (!parser) {
+        IPX_CTX_ERROR(ctx, "Memory allocation error (%s:%d)", __FILE__, __LINE__);
+        goto error;
+    }
+
+    if (fds_xml_set_args(parser, args_params) != FDS_OK) {
+        IPX_CTX_ERROR(ctx, "Failed to parse the description of an XML document!");
+        goto error;
+    }
+
+    fds_xml_ctx_t *params_ctx = fds_xml_parse_mem(parser, params, true);
+    if (params_ctx == NULL) {
+        IPX_CTX_ERROR(ctx, "Failed to parse the configuration: %s", fds_xml_last_err(parser));
+        goto error;
+    }
+
+    const struct fds_xml_cont *content;
+    while (fds_xml_next(params_ctx, &content) == FDS_OK) {
+        switch (content->id) {
+            case EXTENSION_IDS:
+            {
+                if( cfg->ids_count >= CONFIG_IDS_MAX ) {
+                    IPX_CTX_ERROR(ctx, "Maximum number of extension uniq ids exceeded (%d)!", CONFIG_IDS_MAX);
+                    goto error;
+                }
+                config_ids_t* id = &cfg->ids[cfg->ids_count];
+                id->name = NULL;                
+                if( config_parse_ids(ctx, content, id) != 0 ) {
+                    goto error;
+                }
+                cfg->ids_count++;
+                break;
+            }
+            default:
+                break;
+        }
+    }
+    fds_xml_destroy(parser);
+    return cfg;
+
+error:
+    fds_xml_destroy(parser);
+    config_destroy(cfg);
+    return NULL;
+}
+
+void
+config_destroy(struct config *cfg)
+{
+    if (cfg == NULL) {
+        return;
+    }
+    for( int i = 0; i < cfg->ids_count; i++) {
+        printf("Free filter %s\n", cfg->ids[i].name);
+        for( int v =0; v < cfg->ids[i].values_count; v++) {
+            if( cfg->ids[i].values[v].expr ) {
+                free(cfg->ids[i].values[v].expr);
+                cfg->ids[i].values[v].expr = NULL;
+            }
+            if( cfg->ids[i].values[v].value ) {
+                free(cfg->ids[i].values[v].value);
+                cfg->ids[i].values[v].value = NULL;
+            }
+            if( cfg->ids[i].values[v].filter ) {
+                fds_ipfix_filter_destroy(cfg->ids[i].values[v].filter);
+                cfg->ids[i].values[v].filter = NULL;
+            }
+        }
+        if( cfg->ids[i].name ) {
+            free(cfg->ids[i].name);
+            cfg->ids[i].name = NULL;
+        }
+    }
+    free(cfg);
+}