1 files changed, 401 insertions, 0 deletions
diff --git a/support/junction/xml.c b/support/junction/xml.c
new file mode 100644
index 0000000..813110b
--- /dev/null
+++ b/support/junction/xml.c
@@ -0,0 +1,401 @@
+/**
+ * @file support/junction/xml.c
+ * @brief Common utilities for managing junction XML
+ */
+
+/*
+ * Copyright 2011, 2018 Oracle.  All rights reserved.
+ *
+ * This file is part of nfs-utils.
+ *
+ * nfs-utils is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2.0 as
+ * published by the Free Software Foundation.
+ *
+ * nfs-utils is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License version 2.0 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2.0 along with nfs-utils.  If not, see:
+ *
+ *	http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "junction.h"
+#include "junction-internal.h"
+#include "xlog.h"
+
+/**
+ * Predicate: is element content empty?
+ *
+ * @param content element content to test
+ * @return true if content is empty
+ */
+_Bool
+junction_xml_is_empty(const xmlChar *content)
+{
+	return content == NULL || *content == '\0';
+}
+
+/**
+ * Match an XML parse tree node by its name
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param name NUL-terminated C string containing name to match
+ * @return true if "node" is named "name"
+ */
+_Bool
+junction_xml_match_node_name(xmlNodePtr node, const xmlChar *name)
+{
+	return (node->type == XML_ELEMENT_NODE) &&
+		(xmlStrcmp(node->name, name) == 0);
+}
+
+/**
+ * Find a first-level child of "parent" named "name"
+ *
+ * @param parent pointer to node whose children are to be searched
+ * @param name NUL-terminated C string containing name to match
+ * @return pointer to child of "parent" whose name is "name"
+ */
+xmlNodePtr
+junction_xml_find_child_by_name(xmlNodePtr parent, const xmlChar *name)
+{
+	xmlNodePtr node;
+
+	for (node = parent->children; node != NULL; node = node->next)
+		if (junction_xml_match_node_name(node, name))
+			return node;
+	return NULL;
+}
+
+/**
+ * Read attribute into a boolean
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param attrname NUL-terminated C string containing attribute name
+ * @param value OUT: attribute's value converted to an integer
+ * @return true if attribute "attrname" has a valid boolean value
+ */
+_Bool
+junction_xml_get_bool_attribute(xmlNodePtr node, const xmlChar *attrname,
+		_Bool *value)
+{
+	xmlChar *prop;
+	_Bool retval;
+
+	retval = false;
+	prop = xmlGetProp(node, attrname);
+	if (prop == NULL)
+		goto out;
+
+	if (xmlStrcmp(prop, (const xmlChar *)"true") == 0) {
+		*value = true;
+		retval = true;
+		goto out;
+	}
+
+	if (xmlStrcmp(prop, (const xmlChar *)"false") == 0) {
+		*value = false;
+		retval = true;
+		goto out;
+	}
+
+out:
+	xmlFree(prop);
+	return retval;
+}
+
+/**
+ * Set attribute to a boolean
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param attrname NUL-terminated C string containing attribute name
+ * @param value boolean value to set
+ */
+void
+junction_xml_set_bool_attribute(xmlNodePtr node, const xmlChar *attrname,
+					_Bool value)
+{
+	xmlSetProp(node, attrname, (const xmlChar *)(value ? "true" : "false"));
+}
+
+/**
+ * Read attribute into an uint8_t
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param attrname NUL-terminated C string containing attribute name
+ * @param value OUT: attribute's value converted to an uint8_t
+ * @return true if attribute "attrname" has a valid uint8_t value
+ */
+_Bool
+junction_xml_get_u8_attribute(xmlNodePtr node, const xmlChar *attrname,
+		uint8_t *value)
+{
+	char *endptr;
+	_Bool retval;
+	char *prop;
+	long tmp;
+
+	retval = false;
+	prop = (char *)xmlGetProp(node, attrname);
+	if (prop == NULL)
+		goto out;
+
+	errno = 0;
+	tmp = strtol(prop, &endptr, 10);
+	if (errno != 0 || *endptr != '\0' || tmp > 255 || tmp < 0)
+		goto out;
+
+	*value = (uint8_t)tmp;
+	retval = true;
+
+out:
+	xmlFree(prop);
+	return retval;
+}
+
+/**
+ * Read attribute into an integer
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param attrname NUL-terminated C string containing attribute name
+ * @param value OUT: attribute's value converted to an integer
+ * @return true if attribute "attrname" has a valid integer value
+ */
+_Bool
+junction_xml_get_int_attribute(xmlNodePtr node, const xmlChar *attrname,
+		int *value)
+{
+	char *endptr;
+	_Bool retval;
+	char *prop;
+	long tmp;
+
+	retval = false;
+	prop = (char *)xmlGetProp(node, attrname);
+	if (prop == NULL)
+		goto out;
+
+	errno = 0;
+	tmp = strtol(prop, &endptr, 10);
+	if (errno != 0 || *endptr != '\0' || tmp > INT32_MAX || tmp < INT32_MIN)
+		goto out;
+
+	*value = (int)tmp;
+	retval = true;
+
+out:
+	xmlFree(prop);
+	return retval;
+}
+
+/**
+ * Set attribute to an integer
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param attrname NUL-terminated C string containing attribute name
+ * @param value integer value to set
+ */
+void
+junction_xml_set_int_attribute(xmlNodePtr node, const xmlChar *attrname,
+		int value)
+{
+	char buf[16];
+
+	snprintf(buf, sizeof(buf), "%d", value);
+	xmlSetProp(node, attrname, (const xmlChar *)buf);
+}
+
+/**
+ * Read node content into an integer
+ *
+ * @param node pointer to a node in an XML parse tree
+ * @param value OUT: node's content converted to an integer
+ * @return true if "node" has valid integer content
+ */
+_Bool
+junction_xml_get_int_content(xmlNodePtr node, int *value)
+{
+	xmlChar *content;
+	char *endptr;
+	_Bool retval;
+	long tmp;
+
+	retval = false;
+	content = xmlNodeGetContent(node);
+	if (content == NULL)
+		goto out;
+
+	errno = 0;
+	tmp = strtol((const char *)content, &endptr, 10);
+	if (errno != 0 || *endptr != '\0' || tmp > INT32_MAX || tmp < INT32_MIN)
+		goto out;
+
+	*value = (int)tmp;
+	retval = true;
+
+out:
+	xmlFree(content);
+	return retval;
+}
+
+/**
+ * Add a child node with integer content
+ *
+ * @param parent  pointer to a node in an XML parse tree
+ * @param name NUL-terminated C string containing name of child to add
+ * @param value set node content to this value
+ * @return pointer to new child node
+ */
+xmlNodePtr
+junction_xml_set_int_content(xmlNodePtr parent, const xmlChar *name, int value)
+{
+	char buf[16];
+
+	snprintf(buf, sizeof(buf), "%d", value);
+	return xmlNewTextChild(parent, NULL, name, (const xmlChar *)buf);
+}
+
+/**
+ * Parse XML document in a buffer into an XML document tree
+ *
+ * @param pathname NUL-terminated C string containing pathname of a directory
+ * @param name NUL-terminated C string containing name of xattr to replace
+ * @param buf opaque byte array containing XML to parse
+ * @param len size of "buf" in bytes
+ * @param doc OUT: an XML parse tree containing junction XML
+ * @return a FedFsStatus code
+ *
+ * If junction_parse_xml_buf() returns success, caller must free "*doc"
+ * using xmlFreeDoc(3).
+ *
+ * @note Access to trusted attributes requires CAP_SYS_ADMIN.
+ */
+static FedFsStatus
+junction_parse_xml_buf(const char *pathname, const char *name,
+		void *buf, size_t len, xmlDocPtr *doc)
+{
+	xmlDocPtr tmp;
+
+	tmp = xmlParseMemory(buf, (int)len);
+	if (tmp == NULL) {
+		xlog(D_GENERAL, "Failed to parse XML in %s(%s)\n",
+			pathname, name);
+		return FEDFS_ERR_SVRFAULT;
+	}
+
+	*doc = tmp;
+	return FEDFS_OK;
+}
+
+/**
+ * Read an XML document from an extended attribute into an XML document tree
+ *
+ * @param pathname NUL-terminated C string containing pathname of a directory
+ * @param fd an open file descriptor
+ * @param name NUL-terminated C string containing name of xattr to replace
+ * @param doc OUT: an XML parse tree containing junction XML
+ * @return a FedFsStatus code
+ *
+ * If junction_parse_xml_read() returns success, caller must free "*doc"
+ * using xmlFreeDoc(3).
+ *
+ * @note Access to trusted attributes requires CAP_SYS_ADMIN.
+ */
+static FedFsStatus
+junction_parse_xml_read(const char *pathname, int fd, const char *name,
+		xmlDocPtr *doc)
+{
+	FedFsStatus retval;
+	void *buf = NULL;
+	size_t len;
+
+	retval = junction_get_xattr(fd, pathname, name, &buf, &len);
+	if (retval != FEDFS_OK)
+		return retval;
+
+	xlog(D_CALL, "%s: XML document contained in junction:\n%zu.%s",
+		__func__, len, (char *)buf);
+
+	retval = junction_parse_xml_buf(pathname, name, buf, len, doc);
+
+	free(buf);
+	return retval;
+}
+
+/**
+ * Read an XML document from an extended attribute into an XML document tree
+ *
+ * @param pathname NUL-terminated C string containing pathname of a directory
+ * @param name NUL-terminated C string containing name of xattr to replace
+ * @param doc OUT: an XML parse tree containing junction XML
+ * @return a FedFsStatus code
+ *
+ * If junction_parse_xml() returns success, caller must free "*doc"
+ * using xmlFreeDoc(3).
+ *
+ * @note Access to trusted attributes requires CAP_SYS_ADMIN.
+ */
+FedFsStatus
+junction_xml_parse(const char *pathname, const char *name, xmlDocPtr *doc)
+{
+	FedFsStatus retval;
+	int fd;
+
+	retval = junction_open_path(pathname, &fd);
+	if (retval != FEDFS_OK)
+		return retval;
+
+	retval = junction_parse_xml_read(pathname, fd, name, doc);
+
+	(void)close(fd);
+	return retval;
+}
+
+/**
+ * Write an XML document into an extended attribute
+ *
+ * @param pathname NUL-terminated C string containing pathname of a directory
+ * @param name NUL-terminated C string containing name of xattr to replace
+ * @param doc an XML parse tree containing junction XML
+ * @return a FedFsStatus code
+ *
+ * @note Access to trusted attributes requires CAP_SYS_ADMIN.
+ */
+FedFsStatus
+junction_xml_write(const char *pathname, const char *name, xmlDocPtr doc)
+{
+	xmlChar *buf = NULL;
+	FedFsStatus retval;
+	int fd, len;
+
+	retval = junction_open_path(pathname, &fd);
+	if (retval != FEDFS_OK)
+		return retval;
+
+	retval = FEDFS_ERR_SVRFAULT;
+	xmlIndentTreeOutput = 1;
+	xmlDocDumpFormatMemoryEnc(doc, &buf, &len, "UTF-8", 1);
+	if (len < 0)
+		goto out;
+
+	retval = junction_set_xattr(fd, pathname, name, buf, (size_t)len);
+
+out:
+	xmlFree(buf);
+	(void)close(fd);
+	return retval;
+}