1/*
2 * "Canonical XML" implementation
3 * http://www.w3.org/TR/xml-c14n
4 *
5 * "Exclusive XML Canonicalization" implementation
6 * http://www.w3.org/TR/xml-exc-c14n
7 *
8 * See Copyright for the status of this software.
9 *
10 * Author: Aleksey Sanin <aleksey@aleksey.com>
11 */
12#define IN_LIBXML
13#include "libxml.h"
14#ifdef LIBXML_C14N_ENABLED
15#ifdef LIBXML_OUTPUT_ENABLED
16
17#ifdef HAVE_STDLIB_H
18#include <stdlib.h>
19#endif
20#include <string.h>
21
22#include <libxml/tree.h>
23#include <libxml/parser.h>
24#include <libxml/uri.h>
25#include <libxml/xmlerror.h>
26#include <libxml/globals.h>
27#include <libxml/xpathInternals.h>
28#include <libxml/c14n.h>
29
30/************************************************************************
31 *									*
32 *		Some declaration better left private ATM		*
33 *									*
34 ************************************************************************/
35
36typedef enum {
37    XMLC14N_BEFORE_DOCUMENT_ELEMENT = 0,
38    XMLC14N_INSIDE_DOCUMENT_ELEMENT = 1,
39    XMLC14N_AFTER_DOCUMENT_ELEMENT = 2
40} xmlC14NPosition;
41
42typedef struct _xmlC14NVisibleNsStack {
43    int nsCurEnd;           /* number of nodes in the set */
44    int nsPrevStart;        /* the begginning of the stack for previous visible node */
45    int nsPrevEnd;          /* the end of the stack for previous visible node */
46    int nsMax;              /* size of the array as allocated */
47    xmlNsPtr 	*nsTab;	    /* array of ns in no particular order */
48    xmlNodePtr	*nodeTab;   /* array of nodes in no particular order */
49} xmlC14NVisibleNsStack, *xmlC14NVisibleNsStackPtr;
50
51typedef struct _xmlC14NCtx {
52    /* input parameters */
53    xmlDocPtr doc;
54    xmlC14NIsVisibleCallback is_visible_callback;
55    void* user_data;
56    int with_comments;
57    xmlOutputBufferPtr buf;
58
59    /* position in the XML document */
60    xmlC14NPosition pos;
61    int parent_is_doc;
62    xmlC14NVisibleNsStackPtr ns_rendered;
63
64    /* C14N mode */
65    xmlC14NMode mode;
66
67    /* exclusive canonicalization */
68    xmlChar **inclusive_ns_prefixes;
69
70    /* error number */
71    int error;
72} xmlC14NCtx, *xmlC14NCtxPtr;
73
74static xmlC14NVisibleNsStackPtr	xmlC14NVisibleNsStackCreate	(void);
75static void     xmlC14NVisibleNsStackDestroy	(xmlC14NVisibleNsStackPtr cur);
76static void     xmlC14NVisibleNsStackAdd	    (xmlC14NVisibleNsStackPtr cur,
77                                                 xmlNsPtr ns,
78                                                 xmlNodePtr node);
79static void 			xmlC14NVisibleNsStackSave	(xmlC14NVisibleNsStackPtr cur,
80								 xmlC14NVisibleNsStackPtr state);
81static void 			xmlC14NVisibleNsStackRestore	(xmlC14NVisibleNsStackPtr cur,
82								 xmlC14NVisibleNsStackPtr state);
83static void 			xmlC14NVisibleNsStackShift	(xmlC14NVisibleNsStackPtr cur);
84static int			xmlC14NVisibleNsStackFind	(xmlC14NVisibleNsStackPtr cur,
85								 xmlNsPtr ns);
86static int			xmlExcC14NVisibleNsStackFind	(xmlC14NVisibleNsStackPtr cur,
87								 xmlNsPtr ns,
88								 xmlC14NCtxPtr ctx);
89
90static int			xmlC14NIsNodeInNodeset		(xmlNodeSetPtr nodes,
91								 xmlNodePtr node,
92								 xmlNodePtr parent);
93
94
95
96static int xmlC14NProcessNode(xmlC14NCtxPtr ctx, xmlNodePtr cur);
97static int xmlC14NProcessNodeList(xmlC14NCtxPtr ctx, xmlNodePtr cur);
98typedef enum {
99    XMLC14N_NORMALIZE_ATTR = 0,
100    XMLC14N_NORMALIZE_COMMENT = 1,
101    XMLC14N_NORMALIZE_PI = 2,
102    XMLC14N_NORMALIZE_TEXT = 3
103} xmlC14NNormalizationMode;
104
105static xmlChar *xmlC11NNormalizeString(const xmlChar * input,
106                                       xmlC14NNormalizationMode mode);
107
108#define 	xmlC11NNormalizeAttr( a ) \
109    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_ATTR)
110#define 	xmlC11NNormalizeComment( a ) \
111    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_COMMENT)
112#define 	xmlC11NNormalizePI( a )	\
113    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_PI)
114#define 	xmlC11NNormalizeText( a ) \
115    xmlC11NNormalizeString((a), XMLC14N_NORMALIZE_TEXT)
116
117#define 	xmlC14NIsVisible( ctx, node, parent ) \
118     (((ctx)->is_visible_callback != NULL) ? \
119	(ctx)->is_visible_callback((ctx)->user_data, \
120		(xmlNodePtr)(node), (xmlNodePtr)(parent)) : 1)
121
122#define 	xmlC14NIsExclusive( ctx ) \
123    ( (ctx)->mode == XML_C14N_EXCLUSIVE_1_0 )
124
125/************************************************************************
126 *									*
127 * 		Some factorized error routines				*
128 *									*
129 ************************************************************************/
130
131/**
132 * xmlC14NErrMemory:
133 * @extra:  extra informations
134 *
135 * Handle a redefinition of memory error
136 */
137static void
138xmlC14NErrMemory(const char *extra)
139{
140    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_C14N,
141		    XML_ERR_NO_MEMORY, XML_ERR_ERROR, NULL, 0, extra,
142		    NULL, NULL, 0, 0,
143		    "Memory allocation failed : %s\n", extra);
144}
145
146/**
147 * xmlC14NErrParam:
148 * @extra:  extra informations
149 *
150 * Handle a redefinition of param error
151 */
152static void
153xmlC14NErrParam(const char *extra)
154{
155    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_C14N,
156		    XML_ERR_INTERNAL_ERROR, XML_ERR_ERROR, NULL, 0, extra,
157		    NULL, NULL, 0, 0,
158		    "Invalid parameter : %s\n", extra);
159}
160
161/**
162 * xmlC14NErrInternal:
163 * @extra:  extra informations
164 *
165 * Handle a redefinition of internal error
166 */
167static void
168xmlC14NErrInternal(const char *extra)
169{
170    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_C14N,
171		    XML_ERR_INTERNAL_ERROR, XML_ERR_ERROR, NULL, 0, extra,
172		    NULL, NULL, 0, 0,
173		    "Internal error : %s\n", extra);
174}
175
176/**
177 * xmlC14NErrInvalidNode:
178 * @extra:  extra informations
179 *
180 * Handle a redefinition of invalid node error
181 */
182static void
183xmlC14NErrInvalidNode(const char *node_type, const char *extra)
184{
185    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_C14N,
186		    XML_C14N_INVALID_NODE, XML_ERR_ERROR, NULL, 0, extra,
187		    NULL, NULL, 0, 0,
188		    "Node %s is invalid here : %s\n", node_type, extra);
189}
190
191/**
192 * xmlC14NErrUnknownNode:
193 * @extra:  extra informations
194 *
195 * Handle a redefinition of unknown node error
196 */
197static void
198xmlC14NErrUnknownNode(int node_type, const char *extra)
199{
200    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_C14N,
201		    XML_C14N_UNKNOW_NODE, XML_ERR_ERROR, NULL, 0, extra,
202		    NULL, NULL, 0, 0,
203		    "Unknown node type %d found : %s\n", node_type, extra);
204}
205
206/**
207 * xmlC14NErrRelativeNamespace:
208 * @extra:  extra informations
209 *
210 * Handle a redefinition of relative namespace error
211 */
212static void
213xmlC14NErrRelativeNamespace(const char *ns_uri)
214{
215    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_C14N,
216		    XML_C14N_RELATIVE_NAMESPACE, XML_ERR_ERROR, NULL, 0, NULL,
217		    NULL, NULL, 0, 0,
218		    "Relative namespace UR is invalid here : %s\n", ns_uri);
219}
220
221
222
223/**
224 * xmlC14NErr:
225 * @ctxt:  a C14N evaluation context
226 * @node:  the context node
227 * @error:  the erorr code
228 * @msg:  the message
229 * @extra:  extra informations
230 *
231 * Handle a redefinition of attribute error
232 */
233static void
234xmlC14NErr(xmlC14NCtxPtr ctxt, xmlNodePtr node, int error,
235           const char * msg)
236{
237    if (ctxt != NULL)
238        ctxt->error = error;
239    __xmlRaiseError(NULL, NULL, NULL,
240		    ctxt, node, XML_FROM_C14N, error,
241		    XML_ERR_ERROR, NULL, 0,
242		    NULL, NULL, NULL, 0, 0, "%s", msg);
243}
244
245/************************************************************************
246 *									*
247 *		The implementation internals				*
248 *									*
249 ************************************************************************/
250#define XML_NAMESPACES_DEFAULT		16
251
252static int
253xmlC14NIsNodeInNodeset(xmlNodeSetPtr nodes, xmlNodePtr node, xmlNodePtr parent) {
254    if((nodes != NULL) && (node != NULL)) {
255	if(node->type != XML_NAMESPACE_DECL) {
256	    return(xmlXPathNodeSetContains(nodes, node));
257	} else {
258	    xmlNs ns;
259
260	    memcpy(&ns, node, sizeof(ns));
261
262	    /* this is a libxml hack! check xpath.c for details */
263	    if((parent != NULL) && (parent->type == XML_ATTRIBUTE_NODE)) {
264		ns.next = (xmlNsPtr)parent->parent;
265	    } else {
266		ns.next = (xmlNsPtr)parent;
267	    }
268
269	    /*
270	     * If the input is an XPath node-set, then the node-set must explicitly
271	     * contain every node to be rendered to the canonical form.
272	     */
273	    return(xmlXPathNodeSetContains(nodes, (xmlNodePtr)&ns));
274	}
275    }
276    return(1);
277}
278
279static xmlC14NVisibleNsStackPtr
280xmlC14NVisibleNsStackCreate(void) {
281    xmlC14NVisibleNsStackPtr ret;
282
283    ret = (xmlC14NVisibleNsStackPtr) xmlMalloc(sizeof(xmlC14NVisibleNsStack));
284    if (ret == NULL) {
285        xmlC14NErrMemory("creating namespaces stack");
286	return(NULL);
287    }
288    memset(ret, 0 , (size_t) sizeof(xmlC14NVisibleNsStack));
289    return(ret);
290}
291
292static void
293xmlC14NVisibleNsStackDestroy(xmlC14NVisibleNsStackPtr cur) {
294    if(cur == NULL) {
295        xmlC14NErrParam("destroying namespaces stack");
296        return;
297    }
298    if(cur->nsTab != NULL) {
299	memset(cur->nsTab, 0, cur->nsMax * sizeof(xmlNsPtr));
300	xmlFree(cur->nsTab);
301    }
302    if(cur->nodeTab != NULL) {
303	memset(cur->nodeTab, 0, cur->nsMax * sizeof(xmlNodePtr));
304	xmlFree(cur->nodeTab);
305    }
306    memset(cur, 0, sizeof(xmlC14NVisibleNsStack));
307    xmlFree(cur);
308
309}
310
311static void
312xmlC14NVisibleNsStackAdd(xmlC14NVisibleNsStackPtr cur, xmlNsPtr ns, xmlNodePtr node) {
313    if((cur == NULL) ||
314       ((cur->nsTab == NULL) && (cur->nodeTab != NULL)) ||
315       ((cur->nsTab != NULL) && (cur->nodeTab == NULL))) {
316        xmlC14NErrParam("adding namespace to stack");
317	return;
318    }
319
320    if ((cur->nsTab == NULL) && (cur->nodeTab == NULL)) {
321        cur->nsTab = (xmlNsPtr*) xmlMalloc(XML_NAMESPACES_DEFAULT * sizeof(xmlNsPtr));
322        cur->nodeTab = (xmlNodePtr*) xmlMalloc(XML_NAMESPACES_DEFAULT * sizeof(xmlNodePtr));
323	if ((cur->nsTab == NULL) || (cur->nodeTab == NULL)) {
324	    xmlC14NErrMemory("adding node to stack");
325	    return;
326	}
327	memset(cur->nsTab, 0 , XML_NAMESPACES_DEFAULT * sizeof(xmlNsPtr));
328	memset(cur->nodeTab, 0 , XML_NAMESPACES_DEFAULT * sizeof(xmlNodePtr));
329        cur->nsMax = XML_NAMESPACES_DEFAULT;
330    } else if(cur->nsMax == cur->nsCurEnd) {
331	void *tmp;
332	int tmpSize;
333
334	tmpSize = 2 * cur->nsMax;
335	tmp = xmlRealloc(cur->nsTab, tmpSize * sizeof(xmlNsPtr));
336	if (tmp == NULL) {
337	    xmlC14NErrMemory("adding node to stack");
338	    return;
339	}
340	cur->nsTab = (xmlNsPtr*)tmp;
341
342	tmp = xmlRealloc(cur->nodeTab, tmpSize * sizeof(xmlNodePtr));
343	if (tmp == NULL) {
344	    xmlC14NErrMemory("adding node to stack");
345	    return;
346	}
347	cur->nodeTab = (xmlNodePtr*)tmp;
348
349	cur->nsMax = tmpSize;
350    }
351    cur->nsTab[cur->nsCurEnd] = ns;
352    cur->nodeTab[cur->nsCurEnd] = node;
353
354    ++cur->nsCurEnd;
355}
356
357static void
358xmlC14NVisibleNsStackSave(xmlC14NVisibleNsStackPtr cur, xmlC14NVisibleNsStackPtr state) {
359    if((cur == NULL) || (state == NULL)) {
360        xmlC14NErrParam("saving namespaces stack");
361	return;
362    }
363
364    state->nsCurEnd = cur->nsCurEnd;
365    state->nsPrevStart = cur->nsPrevStart;
366    state->nsPrevEnd = cur->nsPrevEnd;
367}
368
369static void
370xmlC14NVisibleNsStackRestore(xmlC14NVisibleNsStackPtr cur, xmlC14NVisibleNsStackPtr state) {
371    if((cur == NULL) || (state == NULL)) {
372        xmlC14NErrParam("restoring namespaces stack");
373	return;
374    }
375    cur->nsCurEnd = state->nsCurEnd;
376    cur->nsPrevStart = state->nsPrevStart;
377    cur->nsPrevEnd = state->nsPrevEnd;
378}
379
380static void
381xmlC14NVisibleNsStackShift(xmlC14NVisibleNsStackPtr cur) {
382    if(cur == NULL) {
383        xmlC14NErrParam("shifting namespaces stack");
384	return;
385    }
386    cur->nsPrevStart = cur->nsPrevEnd;
387    cur->nsPrevEnd = cur->nsCurEnd;
388}
389
390static int
391xmlC14NStrEqual(const xmlChar *str1, const xmlChar *str2) {
392    if (str1 == str2) return(1);
393    if (str1 == NULL) return((*str2) == '\0');
394    if (str2 == NULL) return((*str1) == '\0');
395    do {
396	if (*str1++ != *str2) return(0);
397    } while (*str2++);
398    return(1);
399}
400
401/**
402 * xmlC14NVisibleNsStackFind:
403 * @ctx:		the C14N context
404 * @ns:			the namespace to check
405 *
406 * Checks whether the given namespace was already rendered or not
407 *
408 * Returns 1 if we already wrote this namespace or 0 otherwise
409 */
410static int
411xmlC14NVisibleNsStackFind(xmlC14NVisibleNsStackPtr cur, xmlNsPtr ns)
412{
413    int i;
414    const xmlChar *prefix;
415    const xmlChar *href;
416    int has_empty_ns;
417
418    if(cur == NULL) {
419        xmlC14NErrParam("searching namespaces stack (c14n)");
420        return (0);
421    }
422
423    /*
424     * if the default namespace xmlns="" is not defined yet then
425     * we do not want to print it out
426     */
427    prefix = ((ns == NULL) || (ns->prefix == NULL)) ? BAD_CAST "" : ns->prefix;
428    href = ((ns == NULL) || (ns->href == NULL)) ? BAD_CAST "" : ns->href;
429    has_empty_ns = (xmlC14NStrEqual(prefix, NULL) && xmlC14NStrEqual(href, NULL));
430
431    if (cur->nsTab != NULL) {
432	int start = (has_empty_ns) ? 0 : cur->nsPrevStart;
433        for (i = cur->nsCurEnd - 1; i >= start; --i) {
434            xmlNsPtr ns1 = cur->nsTab[i];
435
436	    if(xmlC14NStrEqual(prefix, (ns1 != NULL) ? ns1->prefix : NULL)) {
437		return(xmlC14NStrEqual(href, (ns1 != NULL) ? ns1->href : NULL));
438	    }
439        }
440    }
441    return(has_empty_ns);
442}
443
444static int
445xmlExcC14NVisibleNsStackFind(xmlC14NVisibleNsStackPtr cur, xmlNsPtr ns, xmlC14NCtxPtr ctx) {
446    int i;
447    const xmlChar *prefix;
448    const xmlChar *href;
449    int has_empty_ns;
450
451    if(cur == NULL) {
452        xmlC14NErrParam("searching namespaces stack (exc c14n)");
453        return (0);
454    }
455
456    /*
457     * if the default namespace xmlns="" is not defined yet then
458     * we do not want to print it out
459     */
460    prefix = ((ns == NULL) || (ns->prefix == NULL)) ? BAD_CAST "" : ns->prefix;
461    href = ((ns == NULL) || (ns->href == NULL)) ? BAD_CAST "" : ns->href;
462    has_empty_ns = (xmlC14NStrEqual(prefix, NULL) && xmlC14NStrEqual(href, NULL));
463
464    if (cur->nsTab != NULL) {
465	int start = 0;
466        for (i = cur->nsCurEnd - 1; i >= start; --i) {
467            xmlNsPtr ns1 = cur->nsTab[i];
468
469	    if(xmlC14NStrEqual(prefix, (ns1 != NULL) ? ns1->prefix : NULL)) {
470		if(xmlC14NStrEqual(href, (ns1 != NULL) ? ns1->href : NULL)) {
471	    	    return(xmlC14NIsVisible(ctx, ns1, cur->nodeTab[i]));
472		} else {
473		    return(0);
474		}
475	    }
476        }
477    }
478    return(has_empty_ns);
479}
480
481
482
483
484/**
485 * xmlC14NIsXmlNs:
486 * @ns: 		the namespace to check
487 *
488 * Checks whether the given namespace is a default "xml:" namespace
489 * with href="http://www.w3.org/XML/1998/namespace"
490 *
491 * Returns 1 if the node is default or 0 otherwise
492 */
493
494/* todo: make it a define? */
495static int
496xmlC14NIsXmlNs(xmlNsPtr ns)
497{
498    return ((ns != NULL) &&
499            (xmlStrEqual(ns->prefix, BAD_CAST "xml")) &&
500            (xmlStrEqual(ns->href, XML_XML_NAMESPACE)));
501}
502
503
504/**
505 * xmlC14NNsCompare:
506 * @ns1:		the pointer to first namespace
507 * @ns2: 		the pointer to second namespace
508 *
509 * Compares the namespaces by names (prefixes).
510 *
511 * Returns -1 if ns1 < ns2, 0 if ns1 == ns2 or 1 if ns1 > ns2.
512 */
513static int
514xmlC14NNsCompare(xmlNsPtr ns1, xmlNsPtr ns2)
515{
516    if (ns1 == ns2)
517        return (0);
518    if (ns1 == NULL)
519        return (-1);
520    if (ns2 == NULL)
521        return (1);
522
523    return (xmlStrcmp(ns1->prefix, ns2->prefix));
524}
525
526
527/**
528 * xmlC14NPrintNamespaces:
529 * @ns:			the pointer to namespace
530 * @ctx: 		the C14N context
531 *
532 * Prints the given namespace to the output buffer from C14N context.
533 *
534 * Returns 1 on success or 0 on fail.
535 */
536static int
537xmlC14NPrintNamespaces(const xmlNsPtr ns, xmlC14NCtxPtr ctx)
538{
539
540    if ((ns == NULL) || (ctx == NULL)) {
541        xmlC14NErrParam("writing namespaces");
542        return 0;
543    }
544
545    if (ns->prefix != NULL) {
546        xmlOutputBufferWriteString(ctx->buf, " xmlns:");
547        xmlOutputBufferWriteString(ctx->buf, (const char *) ns->prefix);
548        xmlOutputBufferWriteString(ctx->buf, "=\"");
549    } else {
550        xmlOutputBufferWriteString(ctx->buf, " xmlns=\"");
551    }
552    if(ns->href != NULL) {
553	xmlOutputBufferWriteString(ctx->buf, (const char *) ns->href);
554    }
555    xmlOutputBufferWriteString(ctx->buf, "\"");
556    return (1);
557}
558
559/**
560 * xmlC14NProcessNamespacesAxis:
561 * @ctx: 		the C14N context
562 * @node:		the current node
563 *
564 * Prints out canonical namespace axis of the current node to the
565 * buffer from C14N context as follows
566 *
567 * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
568 *
569 * Namespace Axis
570 * Consider a list L containing only namespace nodes in the
571 * axis and in the node-set in lexicographic order (ascending). To begin
572 * processing L, if the first node is not the default namespace node (a node
573 * with no namespace URI and no local name), then generate a space followed
574 * by xmlns="" if and only if the following conditions are met:
575 *    - the element E that owns the axis is in the node-set
576 *    - The nearest ancestor element of E in the node-set has a default
577 *	    namespace node in the node-set (default namespace nodes always
578 *      have non-empty values in XPath)
579 * The latter condition eliminates unnecessary occurrences of xmlns="" in
580 * the canonical form since an element only receives an xmlns="" if its
581 * default namespace is empty and if it has an immediate parent in the
582 * canonical form that has a non-empty default namespace. To finish
583 * processing  L, simply process every namespace node in L, except omit
584 * namespace node with local name xml, which defines the xml prefix,
585 * if its string value is http://www.w3.org/XML/1998/namespace.
586 *
587 * Exclusive XML Canonicalization v 1.0 (http://www.w3.org/TR/xml-exc-c14n)
588 * Canonical XML applied to a document subset requires the search of the
589 * ancestor nodes of each orphan element node for attributes in the xml
590 * namespace, such as xml:lang and xml:space. These are copied into the
591 * element node except if a declaration of the same attribute is already
592 * in the attribute axis of the element (whether or not it is included in
593 * the document subset). This search and copying are omitted from the
594 * Exclusive XML Canonicalization method.
595 *
596 * Returns 0 on success or -1 on fail.
597 */
598static int
599xmlC14NProcessNamespacesAxis(xmlC14NCtxPtr ctx, xmlNodePtr cur, int visible)
600{
601    xmlNodePtr n;
602    xmlNsPtr ns, tmp;
603    xmlListPtr list;
604    int already_rendered;
605    int has_empty_ns = 0;
606
607    if ((ctx == NULL) || (cur == NULL) || (cur->type != XML_ELEMENT_NODE)) {
608        xmlC14NErrParam("processing namespaces axis (c14n)");
609        return (-1);
610    }
611
612    /*
613     * Create a sorted list to store element namespaces
614     */
615    list = xmlListCreate(NULL, (xmlListDataCompare) xmlC14NNsCompare);
616    if (list == NULL) {
617        xmlC14NErrInternal("creating namespaces list (c14n)");
618        return (-1);
619    }
620
621    /* check all namespaces */
622    for(n = cur; n != NULL; n = n->parent) {
623	for(ns = n->nsDef; ns != NULL; ns = ns->next) {
624	    tmp = xmlSearchNs(cur->doc, cur, ns->prefix);
625
626	    if((tmp == ns) && !xmlC14NIsXmlNs(ns) && xmlC14NIsVisible(ctx, ns, cur)) {
627		already_rendered = xmlC14NVisibleNsStackFind(ctx->ns_rendered, ns);
628		if(visible) {
629        	    xmlC14NVisibleNsStackAdd(ctx->ns_rendered, ns, cur);
630		}
631		if(!already_rendered) {
632		    xmlListInsert(list, ns);
633		}
634    		if(xmlStrlen(ns->prefix) == 0) {
635		    has_empty_ns = 1;
636		}
637	    }
638	}
639    }
640
641    /**
642     * if the first node is not the default namespace node (a node with no
643     * namespace URI and no local name), then generate a space followed by
644     * xmlns="" if and only if the following conditions are met:
645     *  - the element E that owns the axis is in the node-set
646     *  - the nearest ancestor element of E in the node-set has a default
647     *     namespace node in the node-set (default namespace nodes always
648     *     have non-empty values in XPath)
649     */
650    if(visible && !has_empty_ns) {
651        static xmlNs ns_default;
652
653        memset(&ns_default, 0, sizeof(ns_default));
654        if(!xmlC14NVisibleNsStackFind(ctx->ns_rendered, &ns_default)) {
655    	    xmlC14NPrintNamespaces(&ns_default, ctx);
656	}
657    }
658
659
660    /*
661     * print out all elements from list
662     */
663    xmlListWalk(list, (xmlListWalker) xmlC14NPrintNamespaces, (const void *) ctx);
664
665    /*
666     * Cleanup
667     */
668    xmlListDelete(list);
669    return (0);
670}
671
672
673/**
674 * xmlExcC14NProcessNamespacesAxis:
675 * @ctx: 		the C14N context
676 * @node:		the current node
677 *
678 * Prints out exclusive canonical namespace axis of the current node to the
679 * buffer from C14N context as follows
680 *
681 * Exclusive XML Canonicalization
682 * http://www.w3.org/TR/xml-exc-c14n
683 *
684 * If the element node is in the XPath subset then output the node in
685 * accordance with Canonical XML except for namespace nodes which are
686 * rendered as follows:
687 *
688 * 1. Render each namespace node iff:
689 *    * it is visibly utilized by the immediate parent element or one of
690 *      its attributes, or is present in InclusiveNamespaces PrefixList, and
691 *    * its prefix and value do not appear in ns_rendered. ns_rendered is
692 *      obtained by popping the state stack in order to obtain a list of
693 *      prefixes and their values which have already been rendered by
694 *      an output ancestor of the namespace node's parent element.
695 * 2. Append the rendered namespace node to the list ns_rendered of namespace
696 * nodes rendered by output ancestors. Push ns_rendered on state stack and
697 * recurse.
698 * 3. After the recursion returns, pop thestate stack.
699 *
700 *
701 * Returns 0 on success or -1 on fail.
702 */
703static int
704xmlExcC14NProcessNamespacesAxis(xmlC14NCtxPtr ctx, xmlNodePtr cur, int visible)
705{
706    xmlNsPtr ns;
707    xmlListPtr list;
708    xmlAttrPtr attr;
709    int already_rendered;
710    int has_empty_ns = 0;
711    int has_visibly_utilized_empty_ns = 0;
712    int has_empty_ns_in_inclusive_list = 0;
713
714    if ((ctx == NULL) || (cur == NULL) || (cur->type != XML_ELEMENT_NODE)) {
715        xmlC14NErrParam("processing namespaces axis (exc c14n)");
716        return (-1);
717    }
718
719    if(!xmlC14NIsExclusive(ctx)) {
720        xmlC14NErrParam("processing namespaces axis (exc c14n)");
721        return (-1);
722
723    }
724
725    /*
726     * Create a sorted list to store element namespaces
727     */
728    list = xmlListCreate(NULL, (xmlListDataCompare) xmlC14NNsCompare);
729    if (list == NULL) {
730        xmlC14NErrInternal("creating namespaces list (exc c14n)");
731        return (-1);
732    }
733
734    /*
735     * process inclusive namespaces:
736     * All namespace nodes appearing on inclusive ns list are
737     * handled as provided in Canonical XML
738     */
739    if(ctx->inclusive_ns_prefixes != NULL) {
740	xmlChar *prefix;
741	int i;
742
743	for (i = 0; ctx->inclusive_ns_prefixes[i] != NULL; ++i) {
744	    prefix = ctx->inclusive_ns_prefixes[i];
745	    /*
746	     * Special values for namespace with empty prefix
747	     */
748            if (xmlStrEqual(prefix, BAD_CAST "#default")
749                || xmlStrEqual(prefix, BAD_CAST "")) {
750                prefix = NULL;
751		has_empty_ns_in_inclusive_list = 1;
752            }
753
754	    ns = xmlSearchNs(cur->doc, cur, prefix);
755	    if((ns != NULL) && !xmlC14NIsXmlNs(ns) && xmlC14NIsVisible(ctx, ns, cur)) {
756		already_rendered = xmlC14NVisibleNsStackFind(ctx->ns_rendered, ns);
757		if(visible) {
758    	    	    xmlC14NVisibleNsStackAdd(ctx->ns_rendered, ns, cur);
759		}
760		if(!already_rendered) {
761	    	    xmlListInsert(list, ns);
762		}
763    		if(xmlStrlen(ns->prefix) == 0) {
764		    has_empty_ns = 1;
765		}
766	    }
767	}
768    }
769
770    /* add node namespace */
771    if(cur->ns != NULL) {
772	ns = cur->ns;
773    } else {
774        ns = xmlSearchNs(cur->doc, cur, NULL);
775	has_visibly_utilized_empty_ns = 1;
776    }
777    if((ns != NULL) && !xmlC14NIsXmlNs(ns)) {
778	if(visible && xmlC14NIsVisible(ctx, ns, cur)) {
779	    if(!xmlExcC14NVisibleNsStackFind(ctx->ns_rendered, ns, ctx)) {
780		xmlListInsert(list, ns);
781	    }
782	}
783	if(visible) {
784    	    xmlC14NVisibleNsStackAdd(ctx->ns_rendered, ns, cur);
785	}
786	if(xmlStrlen(ns->prefix) == 0) {
787	    has_empty_ns = 1;
788	}
789    }
790
791
792    /* add attributes */
793    for(attr = cur->properties; attr != NULL; attr = attr->next) {
794        /*
795         * we need to check that attribute is visible and has non
796         * default namespace (XML Namespaces: "default namespaces
797    	 * do not apply directly to attributes")
798         */
799	if((attr->ns != NULL) && !xmlC14NIsXmlNs(attr->ns) && xmlC14NIsVisible(ctx, attr, cur)) {
800	    already_rendered = xmlExcC14NVisibleNsStackFind(ctx->ns_rendered, attr->ns, ctx);
801	    xmlC14NVisibleNsStackAdd(ctx->ns_rendered, attr->ns, cur);
802	    if(!already_rendered && visible) {
803		xmlListInsert(list, attr->ns);
804	    }
805	    if(xmlStrlen(attr->ns->prefix) == 0) {
806		has_empty_ns = 1;
807	    }
808	} else if((attr->ns != NULL) && (xmlStrlen(attr->ns->prefix) == 0) && (xmlStrlen(attr->ns->href) == 0)) {
809	    has_visibly_utilized_empty_ns = 1;
810	}
811    }
812
813    /*
814     * Process xmlns=""
815     */
816    if(visible && has_visibly_utilized_empty_ns &&
817	    !has_empty_ns && !has_empty_ns_in_inclusive_list) {
818        static xmlNs ns_default;
819
820        memset(&ns_default, 0, sizeof(ns_default));
821
822        already_rendered = xmlExcC14NVisibleNsStackFind(ctx->ns_rendered, &ns_default, ctx);
823	if(!already_rendered) {
824    	    xmlC14NPrintNamespaces(&ns_default, ctx);
825	}
826    } else if(visible && !has_empty_ns && has_empty_ns_in_inclusive_list) {
827        static xmlNs ns_default;
828
829        memset(&ns_default, 0, sizeof(ns_default));
830        if(!xmlC14NVisibleNsStackFind(ctx->ns_rendered, &ns_default)) {
831    	    xmlC14NPrintNamespaces(&ns_default, ctx);
832	}
833    }
834
835
836
837    /*
838     * print out all elements from list
839     */
840    xmlListWalk(list, (xmlListWalker) xmlC14NPrintNamespaces, (const void *) ctx);
841
842    /*
843     * Cleanup
844     */
845    xmlListDelete(list);
846    return (0);
847}
848
849
850/**
851 * xmlC14NIsXmlAttr:
852 * @attr: 		the attr to check
853 *
854 * Checks whether the given attribute is a default "xml:" namespace
855 * with href="http://www.w3.org/XML/1998/namespace"
856 *
857 * Returns 1 if the node is default or 0 otherwise
858 */
859
860/* todo: make it a define? */
861static int
862xmlC14NIsXmlAttr(xmlAttrPtr attr)
863{
864    return ((attr->ns != NULL) &&
865           (xmlC14NIsXmlNs(attr->ns) != 0));
866}
867
868
869/**
870 * xmlC14NAttrsCompare:
871 * @attr1:		the pointer tls o first attr
872 * @attr2: 		the pointer to second attr
873 *
874 * Prints the given attribute to the output buffer from C14N context.
875 *
876 * Returns -1 if attr1 < attr2, 0 if attr1 == attr2 or 1 if attr1 > attr2.
877 */
878static int
879xmlC14NAttrsCompare(xmlAttrPtr attr1, xmlAttrPtr attr2)
880{
881    int ret = 0;
882
883    /*
884     * Simple cases
885     */
886    if (attr1 == attr2)
887        return (0);
888    if (attr1 == NULL)
889        return (-1);
890    if (attr2 == NULL)
891        return (1);
892    if (attr1->ns == attr2->ns) {
893        return (xmlStrcmp(attr1->name, attr2->name));
894    }
895
896    /*
897     * Attributes in the default namespace are first
898     * because the default namespace is not applied to
899     * unqualified attributes
900     */
901    if (attr1->ns == NULL)
902        return (-1);
903    if (attr2->ns == NULL)
904        return (1);
905    if (attr1->ns->prefix == NULL)
906        return (-1);
907    if (attr2->ns->prefix == NULL)
908        return (1);
909
910    ret = xmlStrcmp(attr1->ns->href, attr2->ns->href);
911    if (ret == 0) {
912        ret = xmlStrcmp(attr1->name, attr2->name);
913    }
914    return (ret);
915}
916
917
918/**
919 * xmlC14NPrintAttrs:
920 * @attr:		the pointer to attr
921 * @ctx: 		the C14N context
922 *
923 * Prints out canonical attribute urrent node to the
924 * buffer from C14N context as follows
925 *
926 * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
927 *
928 * Returns 1 on success or 0 on fail.
929 */
930static int
931xmlC14NPrintAttrs(const xmlAttrPtr attr, xmlC14NCtxPtr ctx)
932{
933    xmlChar *value;
934    xmlChar *buffer;
935
936    if ((attr == NULL) || (ctx == NULL)) {
937        xmlC14NErrParam("writing attributes");
938        return (0);
939    }
940
941    xmlOutputBufferWriteString(ctx->buf, " ");
942    if (attr->ns != NULL && xmlStrlen(attr->ns->prefix) > 0) {
943        xmlOutputBufferWriteString(ctx->buf,
944                                   (const char *) attr->ns->prefix);
945        xmlOutputBufferWriteString(ctx->buf, ":");
946    }
947    xmlOutputBufferWriteString(ctx->buf, (const char *) attr->name);
948    xmlOutputBufferWriteString(ctx->buf, "=\"");
949
950    value = xmlNodeListGetString(ctx->doc, attr->children, 1);
951    /* todo: should we log an error if value==NULL ? */
952    if (value != NULL) {
953        buffer = xmlC11NNormalizeAttr(value);
954        xmlFree(value);
955        if (buffer != NULL) {
956            xmlOutputBufferWriteString(ctx->buf, (const char *) buffer);
957            xmlFree(buffer);
958        } else {
959            xmlC14NErrInternal("normalizing attributes axis");
960            return (0);
961        }
962    }
963    xmlOutputBufferWriteString(ctx->buf, "\"");
964    return (1);
965}
966
967/**
968 * xmlC14NFindHiddenParentAttr:
969 *
970 * Finds an attribute in a hidden parent node.
971 *
972 * Returns a pointer to the attribute node (if found) or NULL otherwise.
973 */
974static xmlAttrPtr
975xmlC14NFindHiddenParentAttr(xmlC14NCtxPtr ctx, xmlNodePtr cur, const xmlChar * name, const xmlChar * ns)
976{
977    xmlAttrPtr res;
978    while((cur != NULL) && (!xmlC14NIsVisible(ctx, cur, cur->parent))) {
979        res = xmlHasNsProp(cur, name, ns);
980        if(res != NULL) {
981            return res;
982        }
983
984        cur = cur->parent;
985    }
986
987    return NULL;
988}
989
990/**
991 * xmlC14NFixupBaseAttr:
992 *
993 * Fixes up the xml:base attribute
994 *
995 * Returns the newly created attribute or NULL
996 */
997static xmlAttrPtr
998xmlC14NFixupBaseAttr(xmlC14NCtxPtr ctx, xmlAttrPtr xml_base_attr)
999{
1000    xmlChar * res = NULL;
1001    xmlNodePtr cur;
1002    xmlAttrPtr attr;
1003    xmlChar * tmp_str;
1004    xmlChar * tmp_str2;
1005    int tmp_str_len;
1006
1007    if ((ctx == NULL) || (xml_base_attr == NULL) || (xml_base_attr->parent == NULL)) {
1008        xmlC14NErrParam("processing xml:base attribute");
1009        return (NULL);
1010    }
1011
1012    /* start from current value */
1013    res = xmlNodeListGetString(ctx->doc, xml_base_attr->children, 1);
1014    if(res == NULL) {
1015        xmlC14NErrInternal("processing xml:base attribute - can't get attr value");
1016        return (NULL);
1017    }
1018
1019    /* go up the stack until we find a node that we rendered already */
1020    cur = xml_base_attr->parent->parent;
1021    while((cur != NULL) && (!xmlC14NIsVisible(ctx, cur, cur->parent))) {
1022        attr = xmlHasNsProp(cur, BAD_CAST "base", XML_XML_NAMESPACE);
1023        if(attr != NULL) {
1024            /* get attr value */
1025            tmp_str = xmlNodeListGetString(ctx->doc, attr->children, 1);
1026            if(tmp_str == NULL) {
1027                xmlFree(res);
1028
1029                xmlC14NErrInternal("processing xml:base attribute - can't get attr value");
1030                return (NULL);
1031            }
1032
1033            /* we need to add '/' if our current base uri ends with '..' or '.'
1034            to ensure that we are forced to go "up" all the time */
1035            tmp_str_len = xmlStrlen(tmp_str);
1036            if(tmp_str_len > 1 && tmp_str[tmp_str_len - 2] == '.') {
1037                tmp_str2 = xmlStrcat(tmp_str, BAD_CAST "/");
1038                if(tmp_str2 == NULL) {
1039                    xmlFree(tmp_str);
1040                    xmlFree(res);
1041
1042                    xmlC14NErrInternal("processing xml:base attribute - can't modify uri");
1043                    return (NULL);
1044                }
1045
1046                tmp_str = tmp_str2;
1047            }
1048
1049            /* build uri */
1050            tmp_str2 = xmlBuildURI(res, tmp_str);
1051            if(tmp_str2 == NULL) {
1052                xmlFree(tmp_str);
1053                xmlFree(res);
1054
1055                xmlC14NErrInternal("processing xml:base attribute - can't construct uri");
1056                return (NULL);
1057            }
1058
1059            /* cleanup and set the new res */
1060            xmlFree(tmp_str);
1061            xmlFree(res);
1062            res = tmp_str2;
1063        }
1064
1065        /* next */
1066        cur = cur->parent;
1067    }
1068
1069    /* check if result uri is empty or not */
1070    if((res == NULL) || xmlStrEqual(res, BAD_CAST "")) {
1071        xmlFree(res);
1072        return (NULL);
1073    }
1074
1075    /* create and return the new attribute node */
1076    attr = xmlNewNsProp(NULL, xml_base_attr->ns, BAD_CAST "base", res);
1077    if(attr == NULL) {
1078        xmlFree(res);
1079
1080        xmlC14NErrInternal("processing xml:base attribute - can't construct attribute");
1081        return (NULL);
1082    }
1083
1084    /* done */
1085    xmlFree(res);
1086    return (attr);
1087}
1088
1089/**
1090 * xmlC14NProcessAttrsAxis:
1091 * @ctx: 		the C14N context
1092 * @cur:		the current node
1093 * @parent_visible:	the visibility of parent node
1094 * @all_parents_visible: the visibility of all parent nodes
1095 *
1096 * Prints out canonical attribute axis of the current node to the
1097 * buffer from C14N context as follows
1098 *
1099 * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
1100 *
1101 * Attribute Axis
1102 * In lexicographic order (ascending), process each node that
1103 * is in the element's attribute axis and in the node-set.
1104 *
1105 * The processing of an element node E MUST be modified slightly
1106 * when an XPath node-set is given as input and the element's
1107 * parent is omitted from the node-set.
1108 *
1109 *
1110 * Exclusive XML Canonicalization v 1.0 (http://www.w3.org/TR/xml-exc-c14n)
1111 *
1112 * Canonical XML applied to a document subset requires the search of the
1113 * ancestor nodes of each orphan element node for attributes in the xml
1114 * namespace, such as xml:lang and xml:space. These are copied into the
1115 * element node except if a declaration of the same attribute is already
1116 * in the attribute axis of the element (whether or not it is included in
1117 * the document subset). This search and copying are omitted from the
1118 * Exclusive XML Canonicalization method.
1119 *
1120 * Returns 0 on success or -1 on fail.
1121 */
1122static int
1123xmlC14NProcessAttrsAxis(xmlC14NCtxPtr ctx, xmlNodePtr cur, int parent_visible)
1124{
1125    xmlAttrPtr attr;
1126    xmlListPtr list;
1127    xmlAttrPtr attrs_to_delete = NULL;
1128
1129    /* special processing for 1.1 spec */
1130    xmlAttrPtr xml_base_attr = NULL;
1131    xmlAttrPtr xml_lang_attr = NULL;
1132    xmlAttrPtr xml_space_attr = NULL;
1133
1134    if ((ctx == NULL) || (cur == NULL) || (cur->type != XML_ELEMENT_NODE)) {
1135        xmlC14NErrParam("processing attributes axis");
1136        return (-1);
1137    }
1138
1139    /*
1140     * Create a sorted list to store element attributes
1141     */
1142    list = xmlListCreate(NULL, (xmlListDataCompare) xmlC14NAttrsCompare);
1143    if (list == NULL) {
1144        xmlC14NErrInternal("creating attributes list");
1145        return (-1);
1146    }
1147
1148    switch(ctx->mode) {
1149    case XML_C14N_1_0:
1150        /* The processing of an element node E MUST be modified slightly when an XPath node-set is
1151         * given as input and the element's parent is omitted from the node-set. The method for processing
1152         * the attribute axis of an element E in the node-set is enhanced. All element nodes along E's
1153         * ancestor axis are examined for nearest occurrences of attributes in the xml namespace, such
1154         * as xml:lang and xml:space (whether or not they are in the node-set). From this list of attributes,
1155         * remove any that are in E's attribute axis (whether or not they are in the node-set). Then,
1156         * lexicographically merge this attribute list with the nodes of E's attribute axis that are in
1157         * the node-set. The result of visiting the attribute axis is computed by processing the attribute
1158         * nodes in this merged attribute list.
1159         */
1160
1161        /*
1162         * Add all visible attributes from current node.
1163         */
1164        attr = cur->properties;
1165        while (attr != NULL) {
1166            /* check that attribute is visible */
1167            if (xmlC14NIsVisible(ctx, attr, cur)) {
1168                xmlListInsert(list, attr);
1169            }
1170            attr = attr->next;
1171        }
1172
1173        /*
1174         * Handle xml attributes
1175         */
1176        if (parent_visible && (cur->parent != NULL) &&
1177            (!xmlC14NIsVisible(ctx, cur->parent, cur->parent->parent)))
1178        {
1179            xmlNodePtr tmp;
1180
1181            /*
1182             * If XPath node-set is not specified then the parent is always
1183             * visible!
1184             */
1185            tmp = cur->parent;
1186            while (tmp != NULL) {
1187                attr = tmp->properties;
1188                while (attr != NULL) {
1189                    if (xmlC14NIsXmlAttr(attr) != 0) {
1190                        if (xmlListSearch(list, attr) == NULL) {
1191                            xmlListInsert(list, attr);
1192                        }
1193                    }
1194                    attr = attr->next;
1195                }
1196                tmp = tmp->parent;
1197            }
1198        }
1199
1200        /* done */
1201        break;
1202    case XML_C14N_EXCLUSIVE_1_0:
1203        /* attributes in the XML namespace, such as xml:lang and xml:space
1204         * are not imported into orphan nodes of the document subset
1205         */
1206
1207        /*
1208         * Add all visible attributes from current node.
1209         */
1210        attr = cur->properties;
1211        while (attr != NULL) {
1212            /* check that attribute is visible */
1213            if (xmlC14NIsVisible(ctx, attr, cur)) {
1214                xmlListInsert(list, attr);
1215            }
1216            attr = attr->next;
1217        }
1218
1219        /* do nothing special for xml attributes */
1220        break;
1221    case XML_C14N_1_1:
1222        /* The processing of an element node E MUST be modified slightly when an XPath node-set is
1223         * given as input and some of the element's ancestors are omitted from the node-set.
1224         *
1225         * Simple inheritable attributes are attributes that have a value that requires at most a simple
1226         * redeclaration. This redeclaration is done by supplying a new value in the child axis. The
1227         * redeclaration of a simple inheritable attribute A contained in one of E's ancestors is done
1228         * by supplying a value to an attribute Ae inside E with the same name. Simple inheritable attributes
1229         * are xml:lang and xml:space.
1230         *
1231         * The method for processing the attribute axis of an element E in the node-set is hence enhanced.
1232         * All element nodes along E's ancestor axis are examined for the nearest occurrences of simple
1233         * inheritable attributes in the xml namespace, such as xml:lang and xml:space (whether or not they
1234         * are in the node-set). From this list of attributes, any simple inheritable attributes that are
1235         * already in E's attribute axis (whether or not they are in the node-set) are removed. Then,
1236         * lexicographically merge this attribute list with the nodes of E's attribute axis that are in
1237         * the node-set. The result of visiting the attribute axis is computed by processing the attribute
1238         * nodes in this merged attribute list.
1239         *
1240         * The xml:id attribute is not a simple inheritable attribute and no processing of these attributes is
1241         * performed.
1242         *
1243         * The xml:base attribute is not a simple inheritable attribute and requires special processing beyond
1244         * a simple redeclaration.
1245         *
1246         * Attributes in the XML namespace other than xml:base, xml:id, xml:lang, and xml:space MUST be processed
1247         * as ordinary attributes.
1248         */
1249
1250        /*
1251         * Add all visible attributes from current node.
1252         */
1253        attr = cur->properties;
1254        while (attr != NULL) {
1255            /* special processing for XML attribute kiks in only when we have invisible parents */
1256            if ((!parent_visible) || (xmlC14NIsXmlAttr(attr) == 0)) {
1257                /* check that attribute is visible */
1258                if (xmlC14NIsVisible(ctx, attr, cur)) {
1259                    xmlListInsert(list, attr);
1260                }
1261            } else {
1262                int matched = 0;
1263
1264                /* check for simple inheritance attributes */
1265                if((!matched) && (xml_lang_attr == NULL) && xmlStrEqual(attr->name, BAD_CAST "lang")) {
1266                    xml_lang_attr = attr;
1267                    matched = 1;
1268                }
1269                if((!matched) && (xml_space_attr == NULL) && xmlStrEqual(attr->name, BAD_CAST "space")) {
1270                    xml_space_attr = attr;
1271                    matched = 1;
1272                }
1273
1274                /* check for base attr */
1275                if((!matched) && (xml_base_attr == NULL) && xmlStrEqual(attr->name, BAD_CAST "base")) {
1276                    xml_base_attr = attr;
1277                    matched = 1;
1278                }
1279
1280                /* otherwise, it is a normal attribute, so just check if it is visible */
1281                if((!matched) && xmlC14NIsVisible(ctx, attr, cur)) {
1282                    xmlListInsert(list, attr);
1283                }
1284            }
1285
1286            /* move to the next one */
1287            attr = attr->next;
1288        }
1289
1290        /* special processing for XML attribute kiks in only when we have invisible parents */
1291        if ((parent_visible)) {
1292
1293            /* simple inheritance attributes - copy */
1294            if(xml_lang_attr == NULL) {
1295                xml_lang_attr = xmlC14NFindHiddenParentAttr(ctx, cur->parent, BAD_CAST "lang", XML_XML_NAMESPACE);
1296            }
1297            if(xml_lang_attr != NULL) {
1298                xmlListInsert(list, xml_lang_attr);
1299            }
1300            if(xml_space_attr == NULL) {
1301                xml_space_attr = xmlC14NFindHiddenParentAttr(ctx, cur->parent, BAD_CAST "space", XML_XML_NAMESPACE);
1302            }
1303            if(xml_space_attr != NULL) {
1304                xmlListInsert(list, xml_space_attr);
1305            }
1306
1307            /* base uri attribute - fix up */
1308            if(xml_base_attr == NULL) {
1309                /* if we don't have base uri attribute, check if we have a "hidden" one above */
1310                xml_base_attr = xmlC14NFindHiddenParentAttr(ctx, cur->parent, BAD_CAST "base", XML_XML_NAMESPACE);
1311            }
1312            if(xml_base_attr != NULL) {
1313                xml_base_attr = xmlC14NFixupBaseAttr(ctx, xml_base_attr);
1314                if(xml_base_attr != NULL) {
1315                    xmlListInsert(list, xml_base_attr);
1316
1317                    /* note that we MUST delete returned attr node ourselves! */
1318                    xml_base_attr->next = attrs_to_delete;
1319                    attrs_to_delete = xml_base_attr;
1320                }
1321            }
1322        }
1323
1324        /* done */
1325        break;
1326    }
1327
1328    /*
1329     * print out all elements from list
1330     */
1331    xmlListWalk(list, (xmlListWalker) xmlC14NPrintAttrs, (const void *) ctx);
1332
1333    /*
1334     * Cleanup
1335     */
1336    xmlFreePropList(attrs_to_delete);
1337    xmlListDelete(list);
1338    return (0);
1339}
1340
1341/**
1342 * xmlC14NCheckForRelativeNamespaces:
1343 * @ctx:		the C14N context
1344 * @cur:		the current element node
1345 *
1346 * Checks that current element node has no relative namespaces defined
1347 *
1348 * Returns 0 if the node has no relative namespaces or -1 otherwise.
1349 */
1350static int
1351xmlC14NCheckForRelativeNamespaces(xmlC14NCtxPtr ctx, xmlNodePtr cur)
1352{
1353    xmlNsPtr ns;
1354
1355    if ((ctx == NULL) || (cur == NULL) || (cur->type != XML_ELEMENT_NODE)) {
1356        xmlC14NErrParam("checking for relative namespaces");
1357        return (-1);
1358    }
1359
1360    ns = cur->nsDef;
1361    while (ns != NULL) {
1362        if (xmlStrlen(ns->href) > 0) {
1363            xmlURIPtr uri;
1364
1365            uri = xmlParseURI((const char *) ns->href);
1366            if (uri == NULL) {
1367                xmlC14NErrInternal("parsing namespace uri");
1368                return (-1);
1369            }
1370            if (xmlStrlen((const xmlChar *) uri->scheme) == 0) {
1371                xmlC14NErrRelativeNamespace(uri->scheme);
1372                xmlFreeURI(uri);
1373                return (-1);
1374            }
1375            if ((xmlStrcasecmp((const xmlChar *) uri->scheme, BAD_CAST "urn") != 0)
1376                && (xmlStrcasecmp((const xmlChar *) uri->scheme, BAD_CAST "dav") !=0)
1377                && (xmlStrlen((const xmlChar *) uri->server) == 0)) {
1378                xmlC14NErrRelativeNamespace(uri->scheme);
1379                xmlFreeURI(uri);
1380                return (-1);
1381            }
1382            xmlFreeURI(uri);
1383        }
1384        ns = ns->next;
1385    }
1386    return (0);
1387}
1388
1389/**
1390 * xmlC14NProcessElementNode:
1391 * @ctx: 		the pointer to C14N context object
1392 * @cur:		the node to process
1393 * @visible:    this node is visible
1394 * @all_parents_visible: whether all the parents of this node are visible
1395 *
1396 * Canonical XML v 1.0 (http://www.w3.org/TR/xml-c14n)
1397 *
1398 * Element Nodes
1399 * If the element is not in the node-set, then the result is obtained
1400 * by processing the namespace axis, then the attribute axis, then
1401 * processing the child nodes of the element that are in the node-set
1402 * (in document order). If the element is in the node-set, then the result
1403 * is an open angle bracket (<), the element QName, the result of
1404 * processing the namespace axis, the result of processing the attribute
1405 * axis, a close angle bracket (>), the result of processing the child
1406 * nodes of the element that are in the node-set (in document order), an
1407 * open angle bracket, a forward slash (/), the element QName, and a close
1408 * angle bracket.
1409 *
1410 * Returns non-negative value on success or negative value on fail
1411 */
1412static int
1413xmlC14NProcessElementNode(xmlC14NCtxPtr ctx, xmlNodePtr cur, int visible)
1414{
1415    int ret;
1416    xmlC14NVisibleNsStack state;
1417    int parent_is_doc = 0;
1418
1419    if ((ctx == NULL) || (cur == NULL) || (cur->type != XML_ELEMENT_NODE)) {
1420        xmlC14NErrParam("processing element node");
1421        return (-1);
1422    }
1423
1424    /*
1425     * Check relative relative namespaces:
1426     * implementations of XML canonicalization MUST report an operation
1427     * failure on documents containing relative namespace URIs.
1428     */
1429    if (xmlC14NCheckForRelativeNamespaces(ctx, cur) < 0) {
1430        xmlC14NErrInternal("checking for relative namespaces");
1431        return (-1);
1432    }
1433
1434
1435    /*
1436     * Save ns_rendered stack position
1437     */
1438    memset(&state, 0, sizeof(state));
1439    xmlC14NVisibleNsStackSave(ctx->ns_rendered, &state);
1440
1441    if (visible) {
1442        if (ctx->parent_is_doc) {
1443	    /* save this flag into the stack */
1444	    parent_is_doc = ctx->parent_is_doc;
1445	    ctx->parent_is_doc = 0;
1446            ctx->pos = XMLC14N_INSIDE_DOCUMENT_ELEMENT;
1447        }
1448        xmlOutputBufferWriteString(ctx->buf, "<");
1449
1450        if ((cur->ns != NULL) && (xmlStrlen(cur->ns->prefix) > 0)) {
1451            xmlOutputBufferWriteString(ctx->buf,
1452                                       (const char *) cur->ns->prefix);
1453            xmlOutputBufferWriteString(ctx->buf, ":");
1454        }
1455        xmlOutputBufferWriteString(ctx->buf, (const char *) cur->name);
1456    }
1457
1458    if (!xmlC14NIsExclusive(ctx)) {
1459        ret = xmlC14NProcessNamespacesAxis(ctx, cur, visible);
1460    } else {
1461        ret = xmlExcC14NProcessNamespacesAxis(ctx, cur, visible);
1462    }
1463    if (ret < 0) {
1464        xmlC14NErrInternal("processing namespaces axis");
1465        return (-1);
1466    }
1467    /* todo: shouldn't this go to "visible only"? */
1468    if(visible) {
1469	xmlC14NVisibleNsStackShift(ctx->ns_rendered);
1470    }
1471
1472    ret = xmlC14NProcessAttrsAxis(ctx, cur, visible);
1473    if (ret < 0) {
1474	xmlC14NErrInternal("processing attributes axis");
1475    	return (-1);
1476    }
1477
1478    if (visible) {
1479        xmlOutputBufferWriteString(ctx->buf, ">");
1480    }
1481    if (cur->children != NULL) {
1482        ret = xmlC14NProcessNodeList(ctx, cur->children);
1483        if (ret < 0) {
1484            xmlC14NErrInternal("processing childrens list");
1485            return (-1);
1486        }
1487    }
1488    if (visible) {
1489        xmlOutputBufferWriteString(ctx->buf, "</");
1490        if ((cur->ns != NULL) && (xmlStrlen(cur->ns->prefix) > 0)) {
1491            xmlOutputBufferWriteString(ctx->buf,
1492                                       (const char *) cur->ns->prefix);
1493            xmlOutputBufferWriteString(ctx->buf, ":");
1494        }
1495        xmlOutputBufferWriteString(ctx->buf, (const char *) cur->name);
1496        xmlOutputBufferWriteString(ctx->buf, ">");
1497        if (parent_is_doc) {
1498	    /* restore this flag from the stack for next node */
1499            ctx->parent_is_doc = parent_is_doc;
1500	    ctx->pos = XMLC14N_AFTER_DOCUMENT_ELEMENT;
1501        }
1502    }
1503
1504    /*
1505     * Restore ns_rendered stack position
1506     */
1507    xmlC14NVisibleNsStackRestore(ctx->ns_rendered, &state);
1508    return (0);
1509}
1510
1511/**
1512 * xmlC14NProcessNode:
1513 * @ctx: 		the pointer to C14N context object
1514 * @cur:		the node to process
1515 *
1516 * Processes the given node
1517 *
1518 * Returns non-negative value on success or negative value on fail
1519 */
1520static int
1521xmlC14NProcessNode(xmlC14NCtxPtr ctx, xmlNodePtr cur)
1522{
1523    int ret = 0;
1524    int visible;
1525
1526    if ((ctx == NULL) || (cur == NULL)) {
1527        xmlC14NErrParam("processing node");
1528        return (-1);
1529    }
1530
1531    visible = xmlC14NIsVisible(ctx, cur, cur->parent);
1532    switch (cur->type) {
1533        case XML_ELEMENT_NODE:
1534            ret = xmlC14NProcessElementNode(ctx, cur, visible);
1535            break;
1536        case XML_CDATA_SECTION_NODE:
1537        case XML_TEXT_NODE:
1538            /*
1539             * Text Nodes
1540             * the string value, except all ampersands are replaced
1541             * by &amp;, all open angle brackets (<) are replaced by &lt;, all closing
1542             * angle brackets (>) are replaced by &gt;, and all #xD characters are
1543             * replaced by &#xD;.
1544             */
1545            /* cdata sections are processed as text nodes */
1546            /* todo: verify that cdata sections are included in XPath nodes set */
1547            if ((visible) && (cur->content != NULL)) {
1548                xmlChar *buffer;
1549
1550                buffer = xmlC11NNormalizeText(cur->content);
1551                if (buffer != NULL) {
1552                    xmlOutputBufferWriteString(ctx->buf,
1553                                               (const char *) buffer);
1554                    xmlFree(buffer);
1555                } else {
1556                    xmlC14NErrInternal("normalizing text node");
1557                    return (-1);
1558                }
1559            }
1560            break;
1561        case XML_PI_NODE:
1562            /*
1563             * Processing Instruction (PI) Nodes-
1564             * The opening PI symbol (<?), the PI target name of the node,
1565             * a leading space and the string value if it is not empty, and
1566             * the closing PI symbol (?>). If the string value is empty,
1567             * then the leading space is not added. Also, a trailing #xA is
1568             * rendered after the closing PI symbol for PI children of the
1569             * root node with a lesser document order than the document
1570             * element, and a leading #xA is rendered before the opening PI
1571             * symbol of PI children of the root node with a greater document
1572             * order than the document element.
1573             */
1574            if (visible) {
1575                if (ctx->pos == XMLC14N_AFTER_DOCUMENT_ELEMENT) {
1576                    xmlOutputBufferWriteString(ctx->buf, "\x0A<?");
1577                } else {
1578                    xmlOutputBufferWriteString(ctx->buf, "<?");
1579                }
1580
1581                xmlOutputBufferWriteString(ctx->buf,
1582                                           (const char *) cur->name);
1583                if ((cur->content != NULL) && (*(cur->content) != '\0')) {
1584                    xmlChar *buffer;
1585
1586                    xmlOutputBufferWriteString(ctx->buf, " ");
1587
1588                    /* todo: do we need to normalize pi? */
1589                    buffer = xmlC11NNormalizePI(cur->content);
1590                    if (buffer != NULL) {
1591                        xmlOutputBufferWriteString(ctx->buf,
1592                                                   (const char *) buffer);
1593                        xmlFree(buffer);
1594                    } else {
1595                        xmlC14NErrInternal("normalizing pi node");
1596                        return (-1);
1597                    }
1598                }
1599
1600                if (ctx->pos == XMLC14N_BEFORE_DOCUMENT_ELEMENT) {
1601                    xmlOutputBufferWriteString(ctx->buf, "?>\x0A");
1602                } else {
1603                    xmlOutputBufferWriteString(ctx->buf, "?>");
1604                }
1605            }
1606            break;
1607        case XML_COMMENT_NODE:
1608            /*
1609             * Comment Nodes
1610             * Nothing if generating canonical XML without  comments. For
1611             * canonical XML with comments, generate the opening comment
1612             * symbol (<!--), the string value of the node, and the
1613             * closing comment symbol (-->). Also, a trailing #xA is rendered
1614             * after the closing comment symbol for comment children of the
1615             * root node with a lesser document order than the document
1616             * element, and a leading #xA is rendered before the opening
1617             * comment symbol of comment children of the root node with a
1618             * greater document order than the document element. (Comment
1619             * children of the root node represent comments outside of the
1620             * top-level document element and outside of the document type
1621             * declaration).
1622             */
1623            if (visible && ctx->with_comments) {
1624                if (ctx->pos == XMLC14N_AFTER_DOCUMENT_ELEMENT) {
1625                    xmlOutputBufferWriteString(ctx->buf, "\x0A<!--");
1626                } else {
1627                    xmlOutputBufferWriteString(ctx->buf, "<!--");
1628                }
1629
1630                if (cur->content != NULL) {
1631                    xmlChar *buffer;
1632
1633                    /* todo: do we need to normalize comment? */
1634                    buffer = xmlC11NNormalizeComment(cur->content);
1635                    if (buffer != NULL) {
1636                        xmlOutputBufferWriteString(ctx->buf,
1637                                                   (const char *) buffer);
1638                        xmlFree(buffer);
1639                    } else {
1640                        xmlC14NErrInternal("normalizing comment node");
1641                        return (-1);
1642                    }
1643                }
1644
1645                if (ctx->pos == XMLC14N_BEFORE_DOCUMENT_ELEMENT) {
1646                    xmlOutputBufferWriteString(ctx->buf, "-->\x0A");
1647                } else {
1648                    xmlOutputBufferWriteString(ctx->buf, "-->");
1649                }
1650            }
1651            break;
1652        case XML_DOCUMENT_NODE:
1653        case XML_DOCUMENT_FRAG_NODE:   /* should be processed as document? */
1654#ifdef LIBXML_DOCB_ENABLED
1655        case XML_DOCB_DOCUMENT_NODE:   /* should be processed as document? */
1656#endif
1657#ifdef LIBXML_HTML_ENABLED
1658        case XML_HTML_DOCUMENT_NODE:   /* should be processed as document? */
1659#endif
1660            if (cur->children != NULL) {
1661                ctx->pos = XMLC14N_BEFORE_DOCUMENT_ELEMENT;
1662                ctx->parent_is_doc = 1;
1663                ret = xmlC14NProcessNodeList(ctx, cur->children);
1664            }
1665            break;
1666
1667        case XML_ATTRIBUTE_NODE:
1668            xmlC14NErrInvalidNode("XML_ATTRIBUTE_NODE", "processing node");
1669            return (-1);
1670        case XML_NAMESPACE_DECL:
1671            xmlC14NErrInvalidNode("XML_NAMESPACE_DECL", "processing node");
1672            return (-1);
1673        case XML_ENTITY_REF_NODE:
1674            xmlC14NErrInvalidNode("XML_ENTITY_REF_NODE", "processing node");
1675            return (-1);
1676        case XML_ENTITY_NODE:
1677            xmlC14NErrInvalidNode("XML_ENTITY_NODE", "processing node");
1678            return (-1);
1679
1680        case XML_DOCUMENT_TYPE_NODE:
1681        case XML_NOTATION_NODE:
1682        case XML_DTD_NODE:
1683        case XML_ELEMENT_DECL:
1684        case XML_ATTRIBUTE_DECL:
1685        case XML_ENTITY_DECL:
1686#ifdef LIBXML_XINCLUDE_ENABLED
1687        case XML_XINCLUDE_START:
1688        case XML_XINCLUDE_END:
1689#endif
1690            /*
1691             * should be ignored according to "W3C Canonical XML"
1692             */
1693            break;
1694        default:
1695            xmlC14NErrUnknownNode(cur->type, "processing node");
1696            return (-1);
1697    }
1698
1699    return (ret);
1700}
1701
1702/**
1703 * xmlC14NProcessNodeList:
1704 * @ctx: 		the pointer to C14N context object
1705 * @cur:		the node to start from
1706 *
1707 * Processes all nodes in the row starting from cur.
1708 *
1709 * Returns non-negative value on success or negative value on fail
1710 */
1711static int
1712xmlC14NProcessNodeList(xmlC14NCtxPtr ctx, xmlNodePtr cur)
1713{
1714    int ret;
1715
1716    if (ctx == NULL) {
1717        xmlC14NErrParam("processing node list");
1718        return (-1);
1719    }
1720
1721    for (ret = 0; cur != NULL && ret >= 0; cur = cur->next) {
1722        ret = xmlC14NProcessNode(ctx, cur);
1723    }
1724    return (ret);
1725}
1726
1727
1728/**
1729 * xmlC14NFreeCtx:
1730 * @ctx: the pointer to C14N context object
1731 *
1732 * Cleanups the C14N context object.
1733 */
1734
1735static void
1736xmlC14NFreeCtx(xmlC14NCtxPtr ctx)
1737{
1738    if (ctx == NULL) {
1739        xmlC14NErrParam("freeing context");
1740        return;
1741    }
1742
1743    if (ctx->ns_rendered != NULL) {
1744        xmlC14NVisibleNsStackDestroy(ctx->ns_rendered);
1745    }
1746    xmlFree(ctx);
1747}
1748
1749/**
1750 * xmlC14NNewCtx:
1751 * @doc: 		the XML document for canonization
1752 * @is_visible_callback:the function to use to determine is node visible
1753 *			or not
1754 * @user_data: 		the first parameter for @is_visible_callback function
1755 *			(in most cases, it is nodes set)
1756 * @mode:   the c14n mode (see @xmlC14NMode)
1757 * @inclusive_ns_prefixe the list of inclusive namespace prefixes
1758 *			ended with a NULL or NULL if there is no
1759 *			inclusive namespaces (only for `
1760 *			canonicalization)
1761 * @with_comments: 	include comments in the result (!=0) or not (==0)
1762 * @buf: 		the output buffer to store canonical XML; this
1763 *			buffer MUST have encoder==NULL because C14N requires
1764 *			UTF-8 output
1765 *
1766 * Creates new C14N context object to store C14N parameters.
1767 *
1768 * Returns pointer to newly created object (success) or NULL (fail)
1769 */
1770static xmlC14NCtxPtr
1771xmlC14NNewCtx(xmlDocPtr doc,
1772	      xmlC14NIsVisibleCallback is_visible_callback, void* user_data,
1773              xmlC14NMode mode, xmlChar ** inclusive_ns_prefixes,
1774              int with_comments, xmlOutputBufferPtr buf)
1775{
1776    xmlC14NCtxPtr ctx = NULL;
1777
1778    if ((doc == NULL) || (buf == NULL)) {
1779        xmlC14NErrParam("creating new context");
1780        return (NULL);
1781    }
1782
1783    /*
1784     *  Validate the encoding output buffer encoding
1785     */
1786    if (buf->encoder != NULL) {
1787        xmlC14NErr(ctx, (xmlNodePtr) doc, XML_C14N_REQUIRES_UTF8,
1788"xmlC14NNewCtx: output buffer encoder != NULL but C14N requires UTF8 output\n");
1789        return (NULL);
1790    }
1791
1792    /*
1793     *  Validate the XML document encoding value, if provided.
1794     */
1795    if (doc->charset != XML_CHAR_ENCODING_UTF8) {
1796        xmlC14NErr(ctx, (xmlNodePtr) doc, XML_C14N_REQUIRES_UTF8,
1797		   "xmlC14NNewCtx: source document not in UTF8\n");
1798        return (NULL);
1799    }
1800
1801    /*
1802     * Allocate a new xmlC14NCtxPtr and fill the fields.
1803     */
1804    ctx = (xmlC14NCtxPtr) xmlMalloc(sizeof(xmlC14NCtx));
1805    if (ctx == NULL) {
1806	xmlC14NErrMemory("creating context");
1807        return (NULL);
1808    }
1809    memset(ctx, 0, sizeof(xmlC14NCtx));
1810
1811    /*
1812     * initialize C14N context
1813     */
1814    ctx->doc = doc;
1815    ctx->with_comments = with_comments;
1816    ctx->is_visible_callback = is_visible_callback;
1817    ctx->user_data = user_data;
1818    ctx->buf = buf;
1819    ctx->parent_is_doc = 1;
1820    ctx->pos = XMLC14N_BEFORE_DOCUMENT_ELEMENT;
1821    ctx->ns_rendered = xmlC14NVisibleNsStackCreate();
1822
1823    if(ctx->ns_rendered == NULL) {
1824        xmlC14NErr(ctx, (xmlNodePtr) doc, XML_C14N_CREATE_STACK,
1825		   "xmlC14NNewCtx: xmlC14NVisibleNsStackCreate failed\n");
1826	xmlC14NFreeCtx(ctx);
1827        return (NULL);
1828    }
1829
1830    /*
1831     * Set "mode" flag and remember list of incluseve prefixes
1832     * for exclusive c14n
1833     */
1834    ctx->mode = mode;
1835    if(xmlC14NIsExclusive(ctx)) {
1836        ctx->inclusive_ns_prefixes = inclusive_ns_prefixes;
1837    }
1838    return (ctx);
1839}
1840
1841/**
1842 * xmlC14NExecute:
1843 * @doc: 		the XML document for canonization
1844 * @is_visible_callback:the function to use to determine is node visible
1845 *			or not
1846 * @user_data: 		the first parameter for @is_visible_callback function
1847 *			(in most cases, it is nodes set)
1848 * @mode:	the c14n mode (see @xmlC14NMode)
1849 * @inclusive_ns_prefixes: the list of inclusive namespace prefixes
1850 *			ended with a NULL or NULL if there is no
1851 *			inclusive namespaces (only for exclusive
1852 *			canonicalization, ignored otherwise)
1853 * @with_comments: 	include comments in the result (!=0) or not (==0)
1854 * @buf: 		the output buffer to store canonical XML; this
1855 *			buffer MUST have encoder==NULL because C14N requires
1856 *			UTF-8 output
1857 *
1858 * Dumps the canonized image of given XML document into the provided buffer.
1859 * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
1860 * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
1861 *
1862 * Returns non-negative value on success or a negative value on fail
1863 */
1864int
1865xmlC14NExecute(xmlDocPtr doc, xmlC14NIsVisibleCallback is_visible_callback,
1866	 void* user_data, int mode, xmlChar **inclusive_ns_prefixes,
1867	 int with_comments, xmlOutputBufferPtr buf) {
1868
1869    xmlC14NCtxPtr ctx;
1870    xmlC14NMode c14n_mode = XML_C14N_1_0;
1871    int ret;
1872
1873    if ((buf == NULL) || (doc == NULL)) {
1874        xmlC14NErrParam("executing c14n");
1875        return (-1);
1876    }
1877
1878    /* for backward compatibility, we have to have "mode" as "int"
1879       and here we check that user gives valid value */
1880    switch(mode) {
1881    case XML_C14N_1_0:
1882    case XML_C14N_EXCLUSIVE_1_0:
1883    case XML_C14N_1_1:
1884         c14n_mode = (xmlC14NMode)mode;
1885         break;
1886    default:
1887        xmlC14NErrParam("invalid mode for executing c14n");
1888        return (-1);
1889    }
1890
1891    /*
1892     *  Validate the encoding output buffer encoding
1893     */
1894    if (buf->encoder != NULL) {
1895        xmlC14NErr(NULL, (xmlNodePtr) doc, XML_C14N_REQUIRES_UTF8,
1896"xmlC14NExecute: output buffer encoder != NULL but C14N requires UTF8 output\n");
1897        return (-1);
1898    }
1899
1900    ctx = xmlC14NNewCtx(doc, is_visible_callback, user_data,
1901	            c14n_mode, inclusive_ns_prefixes,
1902                    with_comments, buf);
1903    if (ctx == NULL) {
1904        xmlC14NErr(NULL, (xmlNodePtr) doc, XML_C14N_CREATE_CTXT,
1905		   "xmlC14NExecute: unable to create C14N context\n");
1906        return (-1);
1907    }
1908
1909
1910
1911    /*
1912     * Root Node
1913     * The root node is the parent of the top-level document element. The
1914     * result of processing each of its child nodes that is in the node-set
1915     * in document order. The root node does not generate a byte order mark,
1916     * XML declaration, nor anything from within the document type
1917     * declaration.
1918     */
1919    if (doc->children != NULL) {
1920        ret = xmlC14NProcessNodeList(ctx, doc->children);
1921        if (ret < 0) {
1922            xmlC14NErrInternal("processing docs children list");
1923            xmlC14NFreeCtx(ctx);
1924            return (-1);
1925        }
1926    }
1927
1928    /*
1929     * Flush buffer to get number of bytes written
1930     */
1931    ret = xmlOutputBufferFlush(buf);
1932    if (ret < 0) {
1933        xmlC14NErrInternal("flushing output buffer");
1934        xmlC14NFreeCtx(ctx);
1935        return (-1);
1936    }
1937
1938    /*
1939     * Cleanup
1940     */
1941    xmlC14NFreeCtx(ctx);
1942    return (ret);
1943}
1944
1945/**
1946 * xmlC14NDocSaveTo:
1947 * @doc: 		the XML document for canonization
1948 * @nodes: 		the nodes set to be included in the canonized image
1949 *      		or NULL if all document nodes should be included
1950 * @mode:		the c14n mode (see @xmlC14NMode)
1951 * @inclusive_ns_prefixes: the list of inclusive namespace prefixes
1952 *			ended with a NULL or NULL if there is no
1953 *			inclusive namespaces (only for exclusive
1954 *			canonicalization, ignored otherwise)
1955 * @with_comments: 	include comments in the result (!=0) or not (==0)
1956 * @buf: 		the output buffer to store canonical XML; this
1957 *			buffer MUST have encoder==NULL because C14N requires
1958 *			UTF-8 output
1959 *
1960 * Dumps the canonized image of given XML document into the provided buffer.
1961 * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
1962 * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
1963 *
1964 * Returns non-negative value on success or a negative value on fail
1965 */
1966int
1967xmlC14NDocSaveTo(xmlDocPtr doc, xmlNodeSetPtr nodes,
1968                 int mode, xmlChar ** inclusive_ns_prefixes,
1969                 int with_comments, xmlOutputBufferPtr buf) {
1970    return(xmlC14NExecute(doc,
1971			(xmlC14NIsVisibleCallback)xmlC14NIsNodeInNodeset,
1972			nodes,
1973			mode,
1974			inclusive_ns_prefixes,
1975			with_comments,
1976			buf));
1977}
1978
1979
1980/**
1981 * xmlC14NDocDumpMemory:
1982 * @doc: 		the XML document for canonization
1983 * @nodes: 		the nodes set to be included in the canonized image
1984 *      		or NULL if all document nodes should be included
1985 * @mode:		the c14n mode (see @xmlC14NMode)
1986 * @inclusive_ns_prefixes: the list of inclusive namespace prefixes
1987 *			ended with a NULL or NULL if there is no
1988 *			inclusive namespaces (only for exclusive
1989 *			canonicalization, ignored otherwise)
1990 * @with_comments: 	include comments in the result (!=0) or not (==0)
1991 * @doc_txt_ptr: 	the memory pointer for allocated canonical XML text;
1992 *			the caller of this functions is responsible for calling
1993 *			xmlFree() to free allocated memory
1994 *
1995 * Dumps the canonized image of given XML document into memory.
1996 * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
1997 * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
1998 *
1999 * Returns the number of bytes written on success or a negative value on fail
2000 */
2001int
2002xmlC14NDocDumpMemory(xmlDocPtr doc, xmlNodeSetPtr nodes,
2003                     int mode, xmlChar ** inclusive_ns_prefixes,
2004                     int with_comments, xmlChar ** doc_txt_ptr)
2005{
2006    int ret;
2007    xmlOutputBufferPtr buf;
2008
2009    if (doc_txt_ptr == NULL) {
2010        xmlC14NErrParam("dumping doc to memory");
2011        return (-1);
2012    }
2013
2014    *doc_txt_ptr = NULL;
2015
2016    /*
2017     * create memory buffer with UTF8 (default) encoding
2018     */
2019    buf = xmlAllocOutputBuffer(NULL);
2020    if (buf == NULL) {
2021        xmlC14NErrMemory("creating output buffer");
2022        return (-1);
2023    }
2024
2025    /*
2026     * canonize document and write to buffer
2027     */
2028    ret = xmlC14NDocSaveTo(doc, nodes, mode, inclusive_ns_prefixes,
2029                           with_comments, buf);
2030    if (ret < 0) {
2031        xmlC14NErrInternal("saving doc to output buffer");
2032        (void) xmlOutputBufferClose(buf);
2033        return (-1);
2034    }
2035
2036    ret = buf->buffer->use;
2037    if (ret > 0) {
2038        *doc_txt_ptr = xmlStrndup(buf->buffer->content, ret);
2039    }
2040    (void) xmlOutputBufferClose(buf);
2041
2042    if ((*doc_txt_ptr == NULL) && (ret > 0)) {
2043        xmlC14NErrMemory("coping canonicanized document");
2044        return (-1);
2045    }
2046    return (ret);
2047}
2048
2049/**
2050 * xmlC14NDocSave:
2051 * @doc: 		the XML document for canonization
2052 * @nodes: 		the nodes set to be included in the canonized image
2053 *      		or NULL if all document nodes should be included
2054 * @mode:		the c14n mode (see @xmlC14NMode)
2055 * @inclusive_ns_prefixes: the list of inclusive namespace prefixes
2056 *			ended with a NULL or NULL if there is no
2057 *			inclusive namespaces (only for exclusive
2058 *			canonicalization, ignored otherwise)
2059 * @with_comments: 	include comments in the result (!=0) or not (==0)
2060 * @filename: 		the filename to store canonical XML image
2061 * @compression:	the compression level (zlib requred):
2062 *				-1 - libxml default,
2063 *				 0 - uncompressed,
2064 *				>0 - compression level
2065 *
2066 * Dumps the canonized image of given XML document into the file.
2067 * For details see "Canonical XML" (http://www.w3.org/TR/xml-c14n) or
2068 * "Exclusive XML Canonicalization" (http://www.w3.org/TR/xml-exc-c14n)
2069 *
2070 * Returns the number of bytes written success or a negative value on fail
2071 */
2072int
2073xmlC14NDocSave(xmlDocPtr doc, xmlNodeSetPtr nodes,
2074               int mode, xmlChar ** inclusive_ns_prefixes,
2075               int with_comments, const char *filename, int compression)
2076{
2077    xmlOutputBufferPtr buf;
2078    int ret;
2079
2080    if (filename == NULL) {
2081        xmlC14NErrParam("saving doc");
2082        return (-1);
2083    }
2084#ifdef HAVE_ZLIB_H
2085    if (compression < 0)
2086        compression = xmlGetCompressMode();
2087#endif
2088
2089    /*
2090     * save the content to a temp buffer, use default UTF8 encoding.
2091     */
2092    buf = xmlOutputBufferCreateFilename(filename, NULL, compression);
2093    if (buf == NULL) {
2094        xmlC14NErrInternal("creating temporary filename");
2095        return (-1);
2096    }
2097
2098    /*
2099     * canonize document and write to buffer
2100     */
2101    ret = xmlC14NDocSaveTo(doc, nodes, mode, inclusive_ns_prefixes,
2102                           with_comments, buf);
2103    if (ret < 0) {
2104        xmlC14NErrInternal("cannicanize document to buffer");
2105        (void) xmlOutputBufferClose(buf);
2106        return (-1);
2107    }
2108
2109    /*
2110     * get the numbers of bytes written
2111     */
2112    ret = xmlOutputBufferClose(buf);
2113    return (ret);
2114}
2115
2116
2117
2118/*
2119 * Macro used to grow the current buffer.
2120 */
2121#define growBufferReentrant() {						\
2122    buffer_size *= 2;							\
2123    buffer = (xmlChar *)						\
2124    		xmlRealloc(buffer, buffer_size * sizeof(xmlChar));	\
2125    if (buffer == NULL) {						\
2126	xmlC14NErrMemory("growing buffer");				\
2127	return(NULL);							\
2128    }									\
2129}
2130
2131/**
2132 * xmlC11NNormalizeString:
2133 * @input:		the input string
2134 * @mode:		the normalization mode (attribute, comment, PI or text)
2135 *
2136 * Converts a string to a canonical (normalized) format. The code is stolen
2137 * from xmlEncodeEntitiesReentrant(). Added normalization of \x09, \x0a, \x0A
2138 * and the @mode parameter
2139 *
2140 * Returns a normalized string (caller is responsible for calling xmlFree())
2141 * or NULL if an error occurs
2142 */
2143static xmlChar *
2144xmlC11NNormalizeString(const xmlChar * input,
2145                       xmlC14NNormalizationMode mode)
2146{
2147    const xmlChar *cur = input;
2148    xmlChar *buffer = NULL;
2149    xmlChar *out = NULL;
2150    int buffer_size = 0;
2151
2152    if (input == NULL)
2153        return (NULL);
2154
2155    /*
2156     * allocate an translation buffer.
2157     */
2158    buffer_size = 1000;
2159    buffer = (xmlChar *) xmlMallocAtomic(buffer_size * sizeof(xmlChar));
2160    if (buffer == NULL) {
2161	xmlC14NErrMemory("allocating buffer");
2162        return (NULL);
2163    }
2164    out = buffer;
2165
2166    while (*cur != '\0') {
2167        if ((out - buffer) > (buffer_size - 10)) {
2168            int indx = out - buffer;
2169
2170            growBufferReentrant();
2171            out = &buffer[indx];
2172        }
2173
2174        if ((*cur == '<') && ((mode == XMLC14N_NORMALIZE_ATTR) ||
2175                              (mode == XMLC14N_NORMALIZE_TEXT))) {
2176            *out++ = '&';
2177            *out++ = 'l';
2178            *out++ = 't';
2179            *out++ = ';';
2180        } else if ((*cur == '>') && (mode == XMLC14N_NORMALIZE_TEXT)) {
2181            *out++ = '&';
2182            *out++ = 'g';
2183            *out++ = 't';
2184            *out++ = ';';
2185        } else if ((*cur == '&') && ((mode == XMLC14N_NORMALIZE_ATTR) ||
2186                                     (mode == XMLC14N_NORMALIZE_TEXT))) {
2187            *out++ = '&';
2188            *out++ = 'a';
2189            *out++ = 'm';
2190            *out++ = 'p';
2191            *out++ = ';';
2192        } else if ((*cur == '"') && (mode == XMLC14N_NORMALIZE_ATTR)) {
2193            *out++ = '&';
2194            *out++ = 'q';
2195            *out++ = 'u';
2196            *out++ = 'o';
2197            *out++ = 't';
2198            *out++ = ';';
2199        } else if ((*cur == '\x09') && (mode == XMLC14N_NORMALIZE_ATTR)) {
2200            *out++ = '&';
2201            *out++ = '#';
2202            *out++ = 'x';
2203            *out++ = '9';
2204            *out++ = ';';
2205        } else if ((*cur == '\x0A') && (mode == XMLC14N_NORMALIZE_ATTR)) {
2206            *out++ = '&';
2207            *out++ = '#';
2208            *out++ = 'x';
2209            *out++ = 'A';
2210            *out++ = ';';
2211        } else if ((*cur == '\x0D') && ((mode == XMLC14N_NORMALIZE_ATTR) ||
2212                                        (mode == XMLC14N_NORMALIZE_TEXT) ||
2213                                        (mode == XMLC14N_NORMALIZE_COMMENT) ||
2214					(mode == XMLC14N_NORMALIZE_PI))) {
2215            *out++ = '&';
2216            *out++ = '#';
2217            *out++ = 'x';
2218            *out++ = 'D';
2219            *out++ = ';';
2220        } else {
2221            /*
2222             * Works because on UTF-8, all extended sequences cannot
2223             * result in bytes in the ASCII range.
2224             */
2225            *out++ = *cur;
2226        }
2227        cur++;
2228    }
2229    *out = 0;
2230    return (buffer);
2231}
2232#endif /* LIBXML_OUTPUT_ENABLED */
2233#define bottom_c14n
2234#include "elfgcchack.h"
2235#endif /* LIBXML_C14N_ENABLED */
2236