XML Export / Import Progress:

* Exporter finished
* Imported started. Currently reading in nodes and printing them.
* Add XSD file for automatic validation. Working.

TODO:
* Correcly handle main logic of import export
* Finish importer

CMakeLists.txt

@@ -40,8 +40,18 @@ add_custom_target(
 		mkdir -p ${GEN_HEADER_PATH} && bash "${CMAKE_CURRENT_SOURCE_DIR}/gen_version_header.sh" "${GEN_HEADER_PATH}/version.h"
 	WORKING_DIRECTORY
 		${CMAKE_CURRENT_SOURCE_DIR}
+	COMMENT "Generating version header"
 	)
 
+add_custom_target(schema-header DEPENDS "${GEN_HEADER_PATH}/schema-blob.h")
+add_custom_command(
+	OUTPUT "${GEN_HEADER_PATH}/schema-blob.h"
+	COMMAND mkdir -p ${GEN_HEADER_PATH} && bash -c "xxd -i schema.xsd>${GEN_HEADER_PATH}/schema-blob.h"
+	DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/resources/schema.xsd"
+	WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/resources"
+	COMMENT "Generating XML schema"
+)
+
 add_compile_options(-Wall -Wextra -Wold-style-declaration -Wuninitialized -Wmaybe-uninitialized -Wunused-parameter)
 
 set(FORT_ENABLE_TESTING OFF CACHE INTERNAL "")
@@ -56,7 +66,7 @@ target_link_directories(${PROJECT_NAME} PRIVATE ${ELF_LIBRARY_DIRS} ${LIBXML2_LI
 target_include_directories(${PROJECT_NAME} PRIVATE ${ELF_INCLUDE_DIRS})
 target_include_directories(${PROJECT_NAME} PRIVATE "${CMAKE_CURRENT_BINARY_DIR}/include")
 target_include_directories(${PROJECT_NAME} PRIVATE "include")
-add_dependencies(${PROJECT_NAME} version-header)
+add_dependencies(${PROJECT_NAME} version-header schema-header)
 
 if (DOXYGEN_FOUND)
 	set(DOXYFILE_SRC "${CMAKE_CURRENT_SOURCE_DIR}/doxygen/Doxyfile.in")

include/patchelfcrc/elfpatch.h

@@ -50,6 +50,14 @@ elfpatch_handle_t *elf_patch_open(const char *path, bool readonly);
  */
 int elf_patch_check_for_section(elfpatch_handle_t *ep, const char *section);
 
+/**
+ * @brief Get bit size of opened elf file
+ * @param ep Elfpath handle
+ * @return positive: Bits of ELF file. Either 32 or 64
+ * @return negative, if error
+ */
+int elf_patch_get_bits(elfpatch_handle_t *ep);
+
 /**
  * @brief Get VMA, LMA and size of section
  * @param ep Elfpatch handle

include/patchelfcrc/xml.h

@@ -6,9 +6,35 @@
 #include <patchelfcrc/crc.h>
 #include <patchelfcrc/elfpatch.h>
 
+struct xml_crc_entry {
+    uint64_t vma;
+    uint64_t size;
+    uint32_t crc;
+};
+
+struct xml_crc_import {
+    int elf_bits;
+    struct crc_settings crc_config;
+    SlList *xml_crc_entries; /**< @brief linked list of @ref xml_crc_entry structs */
+};
+
 void xml_init(void);
 
 int xml_write_crcs_to_file(const char *path, const uint32_t *crcs, SlList *section_names,
                const struct crc_settings *crc_params, elfpatch_handle_t *ep);
 
+/**
+ * @brief xml_import_from_file Import from file
+ * @param path Path to import from
+ * @return Returns a newly allocated struct. Must be freed with @ref xml_crc_import_free
+ * @return NULL in case of error
+ */
+struct xml_crc_import *xml_import_from_file(const char *path);
+
+/**
+ * @brief Fully free supplied import data
+ * @param data Data to free
+ */
+void xml_crc_import_free(struct xml_crc_import *data);
+
 #endif /* _ELFPATCHCRC_XML_H_ */

resources/schema.xsd

@@ -0,0 +1,38 @@
+<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
+  <xs:element name="patchelfcrc">
+    <xs:complexType>
+      <xs:sequence>
+        <xs:element name="settings">
+          <xs:complexType>
+            <xs:sequence>
+              <xs:element type="xs:string" name="poly"/>
+              <xs:element type="xs:string" name="start"/>
+              <xs:element type="xs:string" name="rev"/>
+              <xs:element type="xs:string" name="xor"/>
+              <xs:element type="xs:integer" name="elfclass"/>
+            </xs:sequence>
+          </xs:complexType>
+        </xs:element>
+        <xs:element name="sections">
+          <xs:complexType>
+            <xs:sequence>
+              <xs:element name="crc">
+                <xs:complexType>
+                  <xs:simpleContent>
+                    <xs:extension base="xs:string">
+                      <xs:attribute type="xs:string" name="name"/>
+                      <xs:attribute type="xs:integer" name="index"/>
+                      <xs:attribute type="xs:string" name="vma"/>
+                      <xs:attribute type="xs:string" name="size"/>
+                    </xs:extension>
+                  </xs:simpleContent>
+                </xs:complexType>
+              </xs:element>
+            </xs:sequence>
+          </xs:complexType>
+        </xs:element>
+      </xs:sequence>
+      <xs:attribute type="xs:string" name="version"/>
+    </xs:complexType>
+  </xs:element>
+</xs:schema>

src/elfpatch.c

@@ -702,3 +702,24 @@ int elf_patch_get_section_address(elfpatch_handle_t *ep, const char *section,
 
 	return 0;
 }
+
+int elf_patch_get_bits(elfpatch_handle_t *ep)
+{
+	int bitsize;
+
+	ret_val_if_ep_err(ep, -1001);
+
+	switch (ep->class) {
+	case ELFCLASS32:
+		bitsize = 32;
+		break;
+	case ELFCLASS64:
+		bitsize = 64;
+		break;
+	default:
+		bitsize = -1;
+		break;
+	}
+
+	return bitsize;
+}

src/main.c

@@ -459,9 +459,14 @@ int main(int argc, char **argv)
 	}
 
 	if (cmd_opts.export_xml) {
-		xml_write_crcs_to_file(cmd_opts.export_xml, crcs, cmd_opts.section_list, &cmd_opts.crc, ep);
+		if (xml_write_crcs_to_file(cmd_opts.export_xml, crcs, cmd_opts.section_list, &cmd_opts.crc, ep)) {
+			print_err("Error during XML generation\n");
+			ret = -3;
 		}
+		/* Fix this: */
+		(void)xml_import_from_file(cmd_opts.export_xml);
 
+	}
 	elf_patch_close_and_free(ep);
 
 	/* Free the CRCs. This is not strictly necessary... */

src/xml.c

@@ -4,11 +4,14 @@
 #include <libxml/tree.h>
 #include <libxml/encoding.h>
 #include <libxml/xmlwriter.h>
+#include <libxml/xmlreader.h>
 
 #include <stdint.h>
 #include <inttypes.h>
 #include <patchelfcrc/reporting.h>
 #include <patchelfcrc/xml.h>
+#include <patchelfcrc/version.h>
+#include <generated/schema-blob.h>
 
 void xml_init(void)
 {
@@ -19,6 +22,7 @@ int xml_write_crcs_to_file(const char *path, const uint32_t *crcs, SlList *secti
 			   const struct crc_settings *crc_params, elfpatch_handle_t *ep)
 {
 	int ret = 0;
+	int bitsize;
 	xmlTextWriter *writer;
 	SlList *name_iter;
 	const char *section_name;
@@ -36,16 +40,25 @@ int xml_write_crcs_to_file(const char *path, const uint32_t *crcs, SlList *secti
 		goto ret_none;
 	}
 
-	xmlTextWriterSetIndentString(writer, BAD_CAST "\t");
+	//xmlTextWriterSetIndentString(writer, BAD_CAST "\t");
-	xmlTextWriterSetIndent(writer, 1);
+	//xmlTextWriterSetIndent(writer, 1);
 
 	xmlTextWriterStartDocument(writer, NULL, "UTF-8", NULL);
+	/* Generate the root node */
+	xmlTextWriterStartElement(writer, BAD_CAST "patchelfcrc");
+	xmlTextWriterWriteFormatAttribute(writer, BAD_CAST "version", "%s", version_string);
 
 	xmlTextWriterStartElement(writer, BAD_CAST "settings");
 	xmlTextWriterWriteFormatElement(writer, BAD_CAST "poly", "0x%" PRIx64, crc_params->polynomial);
 	xmlTextWriterWriteFormatElement(writer, BAD_CAST "start", "0x%" PRIx32, crc_params->start_value);
 	xmlTextWriterWriteFormatElement(writer, BAD_CAST "rev", "%s", crc_params->rev ? "true" : "false");
 	xmlTextWriterWriteFormatElement(writer, BAD_CAST "xor", "0x%" PRIx32, crc_params->xor);
+	bitsize = elf_patch_get_bits(ep);
+	if (bitsize < 0) {
+		print_err("Cannot determine ELF class. Generated XML will be faulty.\n");
+		ret |= -1;
+	}
+	xmlTextWriterWriteFormatElement(writer, BAD_CAST "elfclass", "%d", bitsize);
 	xmlTextWriterEndElement(writer); /* End settings */
 
 	xmlTextWriterStartElement(writer, BAD_CAST "sections");
@@ -59,6 +72,7 @@ int xml_write_crcs_to_file(const char *path, const uint32_t *crcs, SlList *secti
 		if (elf_patch_get_section_address(ep, section_name, &vma, &len)) {
 			print_err("Could not retrieve section address / length of section '%s'. XML output will be faulty.\n",
 				  section_name);
+			ret |= -1;
 		}
 		xmlTextWriterWriteFormatAttribute(writer, BAD_CAST "vma", "0x%" PRIx64, vma);
 		xmlTextWriterWriteFormatAttribute(writer, BAD_CAST "size", "0x%" PRIx64, len);
@@ -66,9 +80,150 @@ int xml_write_crcs_to_file(const char *path, const uint32_t *crcs, SlList *secti
 		xmlTextWriterEndElement(writer); /* End crc */
 	}
 	xmlTextWriterEndElement(writer); /* End sections */
+
+	xmlTextWriterEndElement(writer); /* End root node */
+
 	xmlTextWriterEndDocument(writer);
 
 	xmlFreeTextWriter(writer);
 ret_none:
 	return ret;
 }
+
+static struct xml_crc_import *xml_crc_import_alloc(void)
+{
+	struct xml_crc_import *ret = NULL;
+
+	ret = (struct xml_crc_import *)malloc(sizeof(struct xml_crc_import));
+	if (ret)
+		ret->xml_crc_entries = NULL;
+	else
+		print_err("Error. Out of memory. This should never happen\n");
+
+	return ret;
+}
+
+static void recusive_node_iter(xmlNodePtr node, int level)
+{
+	int i;
+	xmlNodePtr iter;
+	xmlAttrPtr attr;
+	xmlChar *t;
+
+	for (i = level; i > 0; i--)
+		printf("    ");
+
+	if (node->content)
+		printf("Node <%s> (%d) >%s<", node->name, node->type, node->content);
+	else
+		printf("Node <%s> (%d)", node->name, node->type);
+	if (node->properties) {
+		for (attr = node->properties; attr; attr = attr->next) {
+			t = xmlNodeListGetString(node->doc, attr->children, 1);
+			printf(" %s=\"%s\"", attr->name, t);
+			xmlFree(t);
+		}
+	}
+	printf("\n");
+	for (iter = node->children; iter; iter = iter->next) {
+		recusive_node_iter(iter, level + 1);
+	}
+}
+
+static bool validate_xml_doc(xmlDocPtr doc)
+{
+	bool ret = false;
+	xmlSchemaParserCtxtPtr parser_ctx = NULL;
+	xmlSchemaPtr schema = NULL;
+	xmlSchemaValidCtxtPtr validation_ctx = NULL;
+	int res;
+
+	parser_ctx = xmlSchemaNewMemParserCtxt((const char *)schema_xsd, schema_xsd_len);
+	if (!parser_ctx) {
+		print_err("Cannot create parse context for built-in XSD. This is a bug. Report this.\n");
+		goto ret_none;
+	}
+
+	schema = xmlSchemaParse(parser_ctx);
+	if (!schema) {
+		print_err("Cannot parse built-in XSD. This is a bug. Report this.\n");
+		goto ret_none;
+	}
+
+	validation_ctx = xmlSchemaNewValidCtxt(schema);
+	if (!validation_ctx) {
+		print_err("Cannot create validation context. This is a bug. Report this.\n");
+		goto ret_none;
+	}
+
+	res = xmlSchemaValidateDoc(validation_ctx, doc);
+	ret = (res == 0 ? true : false);
+
+ret_none:
+	/* Clean up */
+	if (validation_ctx)
+		xmlSchemaFreeValidCtxt(validation_ctx);
+	if (schema)
+		xmlSchemaFree(schema);
+	if (parser_ctx)
+		xmlSchemaFreeParserCtxt(parser_ctx);
+	return ret;
+}
+
+struct xml_crc_import *xml_import_from_file(const char *path)
+{
+	struct xml_crc_import *ret = NULL;
+	xmlDocPtr doc;
+	xmlNodePtr root_node, settings_node, crc_node, iter;
+
+	if (!path)
+		return NULL;
+
+	doc = xmlReadFile(path, NULL, 0);
+	if (!doc) {
+		print_err("Error reading XML file: %s\n", path);
+		goto ret_none;
+	}
+	root_node = xmlDocGetRootElement(doc);
+	if (!root_node) {
+		goto ret_close_doc;
+	}
+
+	/* Validate the document */
+	if (!validate_xml_doc(doc)) {
+		print_err("XML does not match expected format. Cannot import.\n");
+		goto ret_close_doc;
+	}
+
+	/* Allocate xml import structure */
+	ret = xml_crc_import_alloc();
+	if (!ret)
+		goto ret_close_doc;
+
+	recusive_node_iter(root_node, 0);
+
+
+ret_close_doc:
+	/* Free document and all of its children */
+	xmlFreeDoc(doc);
+
+	/* Cleanup global garbage */
+	xmlCleanupParser();
+ret_none:
+	return ret;
+}
+
+static void free_xml_crc_entry(void *entry) {
+	if (entry)
+		free(entry);
+}
+
+void xml_crc_import_free(struct xml_crc_import *data)
+{
+	if (!data)
+		return;
+
+	sl_list_free_full(data->xml_crc_entries, free_xml_crc_entry);
+	data->xml_crc_entries = NULL;
+	free(data);
+}