src/xml.c

   1 /* vim:tw=78:ts=8:sw=4:set ft=c:  */
   2 /*
   3     Copyright (C) 2006-2010 Ben Kibbey <bjk@luxsci.net>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02110-1301  USA
  18 */
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <err.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27 #include <ctype.h>
  28 #include <glib.h>
  29 #include <gcrypt.h>
  30 #include <libxml/xmlwriter.h>
  31
  32 #ifdef HAVE_CONFIG_H
  33 #include <config.h>
  34 #endif
  35
  36 #include "pwmd_error.h"
  37 #include "misc.h"
  38 #include "xml.h"
  39
  40 /*
  41  * 'element' must be allocated.
  42  */
  43 gboolean is_literal_element(gchar **element)
  44 {
  45     gchar *p;
  46
  47     if (!element || !*element)
  48         return FALSE;
  49
  50     if (*(*element) == '!') {
  51         gchar *c;
  52
  53         for (p = *element, c = p+1; *c; c++)
  54             *p++ = *c;
  55
  56         *p = 0;
  57         return TRUE;
  58     }
  59
  60     return FALSE;
  61 }
  62
  63 gboolean valid_xml_element(xmlChar *element)
  64 {
  65     if (!element)
  66         return FALSE;
  67
  68     if (strchr((gchar *)element, '\t') || strchr((gchar *)element, ' ') ||
  69             *element == '!')
  70         return FALSE;
  71
  72     return TRUE;
  73 }
  74
  75 gpg_error_t new_root_element(xmlDocPtr doc, gchar *name)
  76 {
  77     xmlNodePtr root = xmlDocGetRootElement(doc);
  78     xmlNodePtr n;
  79     gchar *p = name;
  80
  81     if (!p || !root)
  82         return EPWMD_LIBXML_ERROR;
  83
  84     if (*p == '!')
  85         p++;
  86
  87     if (!valid_xml_element((xmlChar *)p))
  88         return GPG_ERR_INV_VALUE;
  89
  90     n = xmlNewNode(NULL, (xmlChar *)"element");
  91     n = xmlAddChild(root, n);
  92     return add_attribute(n, "_name", p);
  93 }
  94
  95 xmlDocPtr create_dtd()
  96 {
  97     xmlDocPtr doc;
  98     xmlTextWriterPtr wr = xmlNewTextWriterDoc(&doc, 0);
  99
 100     if (!wr)
 101         return NULL;
 102
 103     if (xmlTextWriterStartDocument(wr, NULL, NULL, NULL))
 104         goto fail;
 105
 106     if (xmlTextWriterStartDTD(wr, (xmlChar *)"pwmd", NULL, NULL) == -1)
 107         goto fail;
 108
 109     if (xmlTextWriterWriteDTDElement(wr, (xmlChar *)"pwmd",
 110                 (xmlChar *)"(element)") == -1)
 111         goto fail;
 112
 113     xmlTextWriterEndDTDElement(wr);
 114
 115     if (xmlTextWriterWriteDTDAttlist(wr, (xmlChar *)"element",
 116             (xmlChar *)"_name CDATA #REQUIRED") == -1)
 117         goto fail;
 118
 119     xmlTextWriterEndDTDAttlist(wr);
 120     xmlTextWriterEndDTD(wr);
 121
 122     if (xmlTextWriterStartElement(wr, (xmlChar *)"pwmd"))
 123         goto fail;
 124
 125     xmlTextWriterEndElement(wr);
 126     xmlTextWriterEndDocument(wr);
 127     xmlFreeTextWriter(wr);
 128     return doc;
 129
 130 fail:
 131     xmlTextWriterEndDocument(wr);
 132     xmlFreeTextWriter(wr);
 133     xmlFreeDoc(doc);
 134     return NULL;
 135 }
 136
 137 xmlChar *new_document()
 138 {
 139     xmlChar *xml;
 140     gint len;
 141     xmlDocPtr doc = create_dtd();
 142
 143     if (!doc)
 144         return NULL;
 145
 146     xmlDocDumpMemory(doc, &xml, &len);
 147     xmlFreeDoc(doc);
 148     return xml;
 149 }
 150
 151 xmlNodePtr find_element_node(xmlNodePtr node)
 152 {
 153     xmlNodePtr n = node;
 154
 155     if (n && n->type == XML_ELEMENT_NODE)
 156         return n;
 157
 158     for (n = node; n; n = n->next) {
 159         if (n->type == XML_ELEMENT_NODE)
 160             return n;
 161     }
 162
 163     return NULL;
 164 }
 165
 166 /*
 167  * Lists root element names; the value of the attribute "_name" of an element
 168  * "element". If there's a target attribute both literal and non-literal
 169  * element names will be added. This is the primary reason why XML entities
 170  * cannot be used. There wouldn't be a way to get the literal an non-literal
 171  * element paths.
 172  */
 173 gpg_error_t list_root_elements(xmlDocPtr doc, GString **result,
 174         gboolean verbose)
 175 {
 176     xmlNodePtr n = NULL;
 177     GSList *list = NULL;
 178     gint total, i;
 179     GString *string;
 180     gpg_error_t rc = 0;
 181
 182     n = xmlDocGetRootElement(doc);
 183
 184     if (!n || !n->children)
 185         return GPG_ERR_NO_VALUE;
 186
 187     for (n = n->children; n; n = n->next) {
 188         xmlAttrPtr a;
 189         xmlChar *val, *target;
 190         GSList *tlist;
 191         gchar *tmp;
 192
 193         if (n->type != XML_ELEMENT_NODE)
 194             continue;
 195
 196         a = xmlHasProp(n, (xmlChar *)"_name");
 197
 198         if (!a || !a->children->content)
 199             continue;
 200
 201         val = xmlNodeGetContent(a->children);
 202
 203         if (!val) {
 204             rc = gpg_error_from_errno(ENOMEM);
 205             goto fail;
 206         }
 207
 208         tmp = g_strdup_printf("!%s%s", (gchar *)val, verbose ? find_element_node(n->children) ? " 1" : " 0" : "");
 209
 210         if (!tmp) {
 211             xmlFree(val);
 212             rc = gpg_error_from_errno(ENOMEM);
 213             goto fail;
 214         }
 215
 216         tlist = g_slist_append(list, tmp);
 217
 218         if (!tlist) {
 219             xmlFree(val);
 220             rc = gpg_error_from_errno(ENOMEM);
 221             goto fail;
 222         }
 223
 224         list = tlist;
 225         target = node_has_attribute(n, (xmlChar *)"target");
 226
 227         if (target) {
 228             gchar *t;
 229
 230             if (verbose) {
 231                 gchar **req = split_input_line((gchar *)target, "\t", 0);
 232                 xmlNodePtr tnode = find_root_element(doc, &req, &rc, NULL, 0, FALSE);
 233
 234                 if (tnode && req[1]) {
 235                     tnode = find_elements(doc, tnode->children, req+1, &rc,
 236                             NULL, NULL, NULL, FALSE, 0, NULL, FALSE);
 237                 }
 238
 239                 g_strfreev(req);
 240                 t = g_strdup_printf("%s%s", (gchar *)val,
 241                         tnode && find_element_node(tnode->children) ? " 1" : " 0");
 242             }
 243             else
 244                 t = g_strdup((gchar *)val);
 245
 246             if (!t) {
 247                 xmlFree(val);
 248                 xmlFree(target);
 249                 rc = gpg_error_from_errno(ENOMEM);
 250                 goto fail;
 251             }
 252
 253             tlist = g_slist_append(list, t);
 254
 255             if (!tlist) {
 256                 g_free(t);
 257                 xmlFree(target);
 258                 rc = gpg_error_from_errno(ENOMEM);
 259                 goto fail;
 260             }
 261
 262             list = tlist;
 263         }
 264
 265         xmlFree(val);
 266         xmlFree(target);
 267     }
 268
 269     total = g_slist_length(list);
 270
 271     if (!total)
 272         return GPG_ERR_NO_VALUE;
 273
 274     string = g_string_new(NULL);
 275
 276     if (!string) {
 277         rc = gpg_error_from_errno(ENOMEM);
 278         goto fail;
 279     }
 280
 281     for (i = 0; i < total; i++) {
 282         gchar *val = g_slist_nth_data(list, i);
 283
 284         g_string_append_printf(string, "%s\n", val);
 285     }
 286
 287     string = g_string_truncate(string, string->len - 1);
 288     *result = string;
 289
 290 fail:
 291     total = g_slist_length(list);
 292
 293     for (i = 0; i < total; i++)
 294         g_free(g_slist_nth_data(list, i));
 295
 296     g_slist_free(list);
 297     return rc;
 298 }
 299
 300 /*
 301  * Prevents a sibling element past the current element path with the same
 302  * element name.
 303  */
 304 static xmlNodePtr find_stop_node(xmlNodePtr node)
 305 {
 306     xmlNodePtr n;
 307
 308     for (n = node->parent->children; n; n = n->next) {
 309         if (n == node)
 310             return n->next;
 311     }
 312
 313     return NULL;
 314 }
 315
 316 /*
 317  * Alot like create_elements_cb() but doesn't use the last element of 'req' as
 318  * content but as an element.
 319  */
 320 xmlNodePtr create_target_elements_cb(xmlNodePtr node, gchar **path,
 321         gpg_error_t *rc, void *data)
 322 {
 323     gint i;
 324     char **req = path;
 325
 326     for (i = 0; req[i]; i++) {
 327         xmlNodePtr n;
 328
 329         if ((n = find_element(node, req[i], find_stop_node(node))) == NULL ||
 330                 (n && n->parent == node->parent)) {
 331             is_literal_element(&req[i]);
 332
 333             if (!valid_xml_element((xmlChar *)req[i])) {
 334                 *rc = GPG_ERR_INV_VALUE;
 335                 return NULL;
 336             }
 337
 338             //n = xmlNewNode(NULL, (xmlChar *)req[i]);
 339             n = xmlNewNode(NULL, (xmlChar *)"element");
 340
 341             if (!n) {
 342                 *rc = gpg_error_from_errno(ENOMEM);
 343                 return NULL;
 344             }
 345
 346             add_attribute(n, "_name", req[i]);
 347             node = xmlAddChild(node, n);
 348
 349             if (!node) {
 350                 *rc = gpg_error_from_errno(ENOMEM);
 351                 return NULL;
 352             }
 353         }
 354         else
 355             node = n;
 356     }
 357
 358     return node;
 359 }
 360
 361 xmlNodePtr find_text_node(xmlNodePtr node)
 362 {
 363     xmlNodePtr n = node;
 364
 365     if (n && n->type == XML_TEXT_NODE)
 366         return n;
 367
 368     for (n = node; n; n = n->next) {
 369         if (n->type == XML_TEXT_NODE)
 370             return n;
 371     }
 372
 373     return NULL;
 374 }
 375
 376 xmlNodePtr create_elements_cb(xmlNodePtr node, gchar **elements,
 377         gpg_error_t *rc, void *data)
 378 {
 379     gint i;
 380     gchar **req = elements;
 381
 382     if (node->type == XML_TEXT_NODE)
 383         node = node->parent;
 384
 385     xmlChar *a = node_has_attribute(node, (xmlChar *)"_name");
 386
 387     if (a)
 388         xmlFree(a);
 389
 390     for (i = 0; req[i]; i++) {
 391         xmlNodePtr n;
 392
 393         if (req[i+1]) {
 394             /*
 395              * Strip the first '!' if needed. If there's another, it's an
 396              * rc. The syntax has already been checked before calling this
 397              * function.
 398              */
 399             is_literal_element(&req[i]);
 400         }
 401
 402         /*
 403          * The value of the element tree.
 404          */
 405         if (!req[i+1]) {
 406             n = find_text_node(node->children);
 407
 408             if (!n)
 409                 /* Use AddContent here to prevent overwriting any children. */
 410                 xmlNodeAddContent(node, (xmlChar *)req[i]);
 411             else if (n && !*req[i])
 412                 xmlNodeSetContent(n, NULL);
 413             else
 414                 xmlNodeSetContent(n, (xmlChar *)req[i]);
 415
 416             break;
 417         }
 418
 419         n = find_element(node, req[i], find_stop_node(node));
 420
 421         /*
 422          * If the found element has the same parent as the current element,
 423          * they are siblings and the new element needs to be created as a
 424          * child of the current element (node).
 425          */
 426         if (n && n->parent == node->parent)
 427             n = NULL;
 428
 429         if (!n) {
 430             if (!valid_xml_element((xmlChar *)req[i])) {
 431                 *rc = GPG_ERR_INV_VALUE;
 432                 return NULL;
 433             }
 434
 435             //n = xmlNewNode(NULL, (xmlChar *)req[i]);
 436             n = xmlNewNode(NULL, (xmlChar *)"element");
 437
 438             if (!n) {
 439                 *rc = gpg_error_from_errno(ENOMEM);
 440                 return NULL;
 441             }
 442
 443             *rc = add_attribute(n, "_name", req[i]);
 444
 445             if (*rc)
 446                 return NULL;
 447
 448             node = xmlAddChild(node, n);
 449
 450             if (!node) {
 451                 *rc = gpg_error_from_errno(ENOMEM);
 452                 return NULL;
 453             }
 454         }
 455         else
 456             node = n;
 457     }
 458
 459     return node;
 460 }
 461
 462 /* The root element is really req[0]. It is need as a pointer in case there is
 463  * a target attribute so it can be updated. */
 464 xmlNodePtr find_root_element(xmlDocPtr doc, gchar ***req, gpg_error_t *rc,
 465         gboolean *target, gint recursion_depth, gboolean stop)
 466 {
 467     xmlNodePtr n = xmlDocGetRootElement(doc);
 468     gint depth = 0;
 469     gchar *root = g_strdup(*req[0]);
 470     gboolean literal = is_literal_element(&root);
 471
 472     if (!root) {
 473         *rc = gpg_error_from_errno(ENOMEM);
 474         return NULL;
 475     }
 476
 477     *rc = 0;
 478     recursion_depth++;
 479
 480     if (max_recursion_depth >= 1 && recursion_depth > max_recursion_depth) {
 481         xmlChar *t = xmlGetNodePath(n);
 482
 483         log_write("%s: %s", pwmd_strerror(GPG_ERR_ELOOP), t);
 484         xmlFree(t);
 485         g_free(root);
 486         *rc = GPG_ERR_ELOOP;
 487         return NULL;
 488     }
 489
 490     while (n) {
 491         if (n->type == XML_ELEMENT_NODE) {
 492             if (depth == 0 && xmlStrEqual(n->name, (xmlChar *)"pwmd")) {
 493                 n = n->children;
 494                 depth++;
 495                 continue;
 496             }
 497
 498             if (depth == 1 && xmlStrEqual(n->name, (xmlChar *)"element")) {
 499                 xmlChar *content = node_has_attribute(n, (xmlChar *)"_name");
 500
 501                 if (!content)
 502                     continue;
 503
 504                 if (xmlStrEqual(content, (xmlChar *)root)) {
 505                     gchar **nreq, **tmp = NULL;
 506
 507                     if (literal == TRUE) {
 508                         xmlFree(content);
 509                         g_free(root);
 510                         return n;
 511                     }
 512
 513                     xmlFree(content);
 514                     content = node_has_attribute(n, (xmlChar *)"target");
 515
 516                     if (target)
 517                         *target = TRUE;
 518
 519                     if (!content || stop) {
 520                         if (content)
 521                             xmlFree(content);
 522
 523                         g_free(root);
 524                         return n;
 525                     }
 526
 527                     if (strchr((gchar *)content, '\t')) {
 528                         nreq = split_input_line((gchar *)content, "\t", 0);
 529                         xmlFree(content);
 530
 531 #if 0
 532                         /*
 533                          * FIXME ENOMEM
 534                          */
 535                         if (!nreq) {
 536                             *rc = gpg_error_from_errno(ENOMEM);
 537                             return NULL;
 538                         }
 539 #endif
 540
 541                         tmp = *req;
 542                         tmp = strvcatv(nreq, tmp+1);
 543                         g_strfreev(nreq);
 544
 545                         if (!tmp) {
 546                             g_free(root);
 547                             *rc = gpg_error_from_errno(ENOMEM);
 548                             return NULL;
 549                         }
 550
 551                         g_strfreev(*req);
 552                         *req = tmp;
 553                     }
 554                     else {
 555                         if (strv_printf(&tmp, "%s", content) == FALSE) {
 556                             xmlFree(content);
 557                             g_free(root);
 558                             *rc = gpg_error_from_errno(ENOMEM);
 559                             return NULL;
 560                         }
 561
 562                         xmlFree(content);
 563                         nreq = *req;
 564                         nreq = strvcatv(tmp, nreq+1);
 565                         g_strfreev(tmp);
 566
 567                         if (!nreq) {
 568                             *rc = gpg_error_from_errno(ENOMEM);
 569                             g_free(root);
 570                             return NULL;
 571                         }
 572
 573                         g_strfreev(*req);
 574                         *req = nreq;
 575                     }
 576
 577                     g_free(root);
 578                     n = find_root_element(doc, req, rc, target, recursion_depth, FALSE);
 579                     return n;
 580                 }
 581
 582                 xmlFree(content);
 583             }
 584         }
 585
 586         n = n->next;
 587     }
 588
 589     g_free(root);
 590     *rc = GPG_ERR_ELEMENT_NOT_FOUND;
 591     return NULL;
 592 }
 593
 594 xmlNodePtr find_element(xmlNodePtr node, gchar *element, xmlNodePtr stop)
 595 {
 596     xmlNodePtr n;
 597
 598     if (!node || !element)
 599         return NULL;
 600
 601     for (n = node; n; n = n->next) {
 602         if (n->type != XML_ELEMENT_NODE)
 603             continue;
 604
 605         if (n == stop)
 606             break;
 607
 608         xmlChar *a = node_has_attribute(n, (xmlChar *)"_name");
 609
 610         if (a && xmlStrEqual(a, (xmlChar *)element)) {
 611             xmlFree(a);
 612             return n;
 613         }
 614
 615         xmlFree(a);
 616     }
 617
 618     return NULL;
 619 }
 620
 621 xmlChar *node_has_attribute(xmlNodePtr n, xmlChar *attr)
 622 {
 623     xmlAttrPtr a = xmlHasProp(n, attr);
 624
 625     if (!a)
 626         return NULL;
 627
 628     if (!a->children || !a->children->content)
 629         return NULL;
 630
 631     return xmlGetProp(n, attr);
 632 }
 633
 634 static gboolean element_to_literal(gchar **element)
 635 {
 636     gchar *p = g_strdup_printf("!%s", *element);
 637
 638     if (!p)
 639         return FALSE;
 640
 641     g_free(*element);
 642     *element = p;
 643     return TRUE;
 644 }
 645
 646 /* Resolves elements in 'req' one at a time. It's recursive in case of
 647  * "target" attributes. */
 648 xmlNodePtr find_elements(xmlDocPtr doc, xmlNodePtr node,
 649         gchar **req, gpg_error_t *rc, gboolean *target,
 650         xmlNodePtr (*found_fn)(xmlNodePtr, gchar **, gpg_error_t *, gchar **, void *),
 651         xmlNodePtr (*not_found_fn)(xmlNodePtr, gchar **, gpg_error_t *, void *),
 652         gboolean is_list_command, gint recursion_depth, void *data, gboolean stop)
 653 {
 654     xmlNodePtr n, last, last_node;
 655     gchar **p;
 656     gint found = 0;
 657
 658     *rc = 0;
 659     recursion_depth++;
 660
 661     if (max_recursion_depth >= 1 && recursion_depth > max_recursion_depth) {
 662         xmlChar *t = xmlGetNodePath(node);
 663
 664         log_write("%s: %s", pwmd_strerror(GPG_ERR_ELOOP), t);
 665         xmlFree(t);
 666         recursion_depth--;
 667         *rc = GPG_ERR_ELOOP;
 668         return NULL;
 669     }
 670
 671     for (last_node = last = n = node, p = req; *p; p++) {
 672         xmlNodePtr tmp;
 673         gchar *t = g_strdup(*p);
 674         gboolean literal;
 675
 676         if (!t) {
 677             *rc = gpg_error_from_errno(ENOMEM);
 678             return NULL;
 679         }
 680
 681         literal = is_literal_element(&t);
 682         n = find_element(last, t, NULL);
 683         g_free(t);
 684
 685         if (!n) {
 686             if (not_found_fn)
 687                 return not_found_fn(found ? last_node : last_node->parent, p, rc, data);
 688
 689             *rc = GPG_ERR_ELEMENT_NOT_FOUND;
 690             return NULL;
 691         }
 692
 693         last = n->children;
 694         last_node = n;
 695         found = 1;
 696
 697         if (literal == FALSE) {
 698             xmlChar *content = node_has_attribute(n, (xmlChar *)"target");
 699             gchar **nreq = NULL, **nnreq;
 700
 701             if (!content) {
 702                 if (is_list_command == TRUE) {
 703                     if (element_to_literal(&(*p)) == FALSE) {
 704                         *rc = gpg_error_from_errno(ENOMEM);
 705                         return NULL;
 706                     }
 707                 }
 708
 709                 continue;
 710             }
 711
 712             if (target)
 713                 *target = TRUE;
 714
 715             if (!*(p+1) && stop) {
 716                 xmlFree(content);
 717                 return n;
 718             }
 719
 720             if (strchr((gchar *)content, '\t') != NULL) {
 721                 if ((nreq = split_input_line((gchar *)content, "\t", 0)) == NULL) {
 722                     xmlFree(content);
 723                     *rc = GPG_ERR_INV_VALUE;
 724                     return NULL;
 725                 }
 726             }
 727             else {
 728                 if ((nreq = split_input_line((gchar *)content, " ", 0)) == NULL) {
 729                     xmlFree(content);
 730                     *rc = GPG_ERR_INV_VALUE;
 731                     return NULL;
 732                 }
 733             }
 734
 735             xmlFree(content);
 736             tmp = find_root_element(doc, &nreq, rc, target, 0, FALSE);
 737
 738             if (!tmp) {
 739                 g_strfreev(nreq);
 740                 return NULL;
 741             }
 742
 743             if (found_fn) {
 744                 found_fn(tmp, nreq, rc, p+1, data);
 745
 746                 if (*rc) {
 747                     g_strfreev(nreq);
 748                     return NULL;
 749                 }
 750             }
 751
 752             nnreq = strvcatv(nreq+1, p+1);
 753             g_strfreev(nreq);
 754
 755             // FIXME ENOMEM
 756             if (!nnreq || !*nnreq) {
 757                 if (nnreq)
 758                     g_strfreev(nnreq);
 759
 760                 return tmp;
 761             }
 762
 763             n = find_elements(doc, tmp->children, nnreq, rc, NULL, found_fn,
 764                     not_found_fn, is_list_command, recursion_depth, data, stop);
 765
 766             if (*(p+1)) {
 767                 gchar **zz = p+1, **qq = nnreq;
 768
 769                 if (g_strv_length(nnreq) > g_strv_length(p+1))
 770                     qq = nnreq+1;
 771
 772                 for (; *qq && *zz; zz++) {
 773                     g_free(*zz);
 774                     *zz = g_strdup(*qq++);
 775
 776                     if (!*zz) {
 777                         *rc = gpg_error_from_errno(ENOMEM);
 778                         n = NULL;
 779                         break;
 780                     }
 781                 }
 782             }
 783
 784             g_strfreev(nnreq);
 785             return n;
 786         }
 787     }
 788
 789     return n;
 790 }
 791
 792 static gboolean update_element_list(struct element_list_s *elements)
 793 {
 794     gchar *line;
 795     GSList *l;
 796
 797     if (!elements || !elements->elements)
 798         return TRUE;
 799
 800     line = g_strjoinv("\t", elements->elements);
 801
 802     if (!line)
 803         return FALSE;
 804
 805     g_strfreev(elements->elements);
 806     elements->elements = NULL;
 807     l = g_slist_append(elements->list, line);
 808
 809     if (!l)
 810         return FALSE;
 811
 812     elements->list = l;
 813     return TRUE;
 814 }
 815
 816 static gpg_error_t path_list_recurse(xmlDocPtr doc, xmlNodePtr node,
 817         struct element_list_s *elements)
 818 {
 819     gpg_error_t rc = 0;
 820     xmlNodePtr n;
 821
 822     for (n = node; n; n = n->next) {
 823         xmlChar *target = NULL;
 824         xmlChar *a = node_has_attribute(n, (xmlChar *)"_name");
 825
 826         if (!a)
 827             continue;
 828
 829         if (n->type != XML_ELEMENT_NODE)
 830             goto children;
 831
 832         if (elements->verbose) {
 833             if (strv_printf(&elements->elements, "%s\t!%s%s", elements->prefix, a, find_element_node(n->children) ? " 1" : " 0") == FALSE) {
 834                 xmlFree(a);
 835                 return gpg_err_code_from_errno(ENOMEM);
 836             }
 837         }
 838         else if (strv_printf(&elements->elements, "%s\t!%s", elements->prefix, a) == FALSE) {
 839             xmlFree(a);
 840             return gpg_err_code_from_errno(ENOMEM);
 841         }
 842
 843         if (update_element_list(elements) == FALSE) {
 844             xmlFree(a);
 845             return gpg_err_code_from_errno(ENOMEM);
 846         }
 847
 848         target = node_has_attribute(n, (xmlChar *)"target");
 849
 850         if (target) {
 851             gchar *tmp;
 852             gchar *save = elements->prefix;
 853             gboolean r = elements->resolving;
 854
 855             elements->depth++;
 856
 857             if (max_recursion_depth >= 1 && elements->depth > max_recursion_depth) {
 858                 xmlChar *t = xmlGetNodePath(n);
 859
 860                 log_write("%s: %s", pwmd_strerror(GPG_ERR_ELOOP), t);
 861                 xmlFree(t);
 862                 xmlFree(target);
 863                 xmlFree(a);
 864                 return GPG_ERR_ELOOP;
 865             }
 866
 867             if (elements->verbose) {
 868                 gchar **req = split_input_line((gchar *)target, "\t", 0);
 869                 xmlNodePtr tnode = find_root_element(doc, &req, &rc, NULL, 0, FALSE);
 870
 871                 if (!tnode) {
 872                     g_strfreev(req);
 873                     xmlFree(a);
 874                     xmlFree(target);
 875                     return rc;
 876                 }
 877
 878                 tnode = find_elements(doc, tnode->children, req+1, &rc, NULL, NULL, NULL, FALSE, 0, NULL, FALSE);
 879                 g_strfreev(req);
 880
 881                 if (!tnode) {
 882                     xmlFree(a);
 883                     xmlFree(target);
 884                     return rc;
 885                 }
 886
 887                 if (strv_printf(&elements->elements, "%s\t%s%s", elements->prefix, a, find_element_node(tnode->children) ? " 1" : " 0") == FALSE) {
 888                     xmlFree(a);
 889                     xmlFree(target);
 890                     return gpg_err_code_from_errno(ENOMEM);
 891                 }
 892             }
 893             else if (strv_printf(&elements->elements, "%s\t%s", elements->prefix, a) == FALSE) {
 894                 xmlFree(a);
 895                 xmlFree(target);
 896                 return gpg_err_code_from_errno(ENOMEM);
 897             }
 898
 899             tmp = g_strjoinv("\t", elements->elements);
 900
 901             if (!tmp) {
 902                 xmlFree(a);
 903                 xmlFree(target);
 904                 return gpg_err_code_from_errno(ENOMEM);
 905             }
 906
 907             if (update_element_list(elements) == FALSE) {
 908                 g_free(tmp);
 909                 xmlFree(a);
 910                 xmlFree(target);
 911                 return gpg_err_code_from_errno(ENOMEM);
 912             }
 913
 914             if (elements->recurse) {
 915                 if (elements->verbose)
 916                     tmp[strlen(tmp)-2] = 0;
 917
 918                 elements->prefix = tmp;
 919                 elements->resolving = TRUE;
 920                 rc = create_path_list(doc, elements, (gchar *)target);
 921                 xmlFree(target);
 922                 elements->resolving = r;
 923                 elements->depth--;
 924                 g_free(tmp);
 925                 elements->prefix = save;
 926
 927                 if (rc) {
 928                     xmlFree(a);
 929                     return rc;
 930                 }
 931             }
 932         }
 933
 934 children:
 935         if (n->children && elements->recurse) {
 936             gchar *tmp = g_strdup_printf("%s\t!%s", elements->prefix, a);
 937             gchar *save = elements->prefix;
 938
 939             if (!tmp) {
 940                 xmlFree(a);
 941                 return gpg_err_code_from_errno(ENOMEM);
 942             }
 943
 944             elements->prefix = tmp;
 945             rc = path_list_recurse(doc, n->children, elements);
 946             g_free(elements->prefix);
 947             elements->prefix = save;
 948
 949             if (rc) {
 950                 xmlFree(a);
 951                 return rc;
 952             }
 953         }
 954
 955         xmlFree(a);
 956     }
 957
 958     return rc;
 959 }
 960
 961 gpg_error_t add_attribute(xmlNodePtr node, const gchar *name,
 962         const gchar *value)
 963 {
 964     gchar *buf;
 965     gpg_error_t rc;
 966
 967     if (name && !xmlSetProp(node, (xmlChar *)name, (xmlChar *)value))
 968         return EPWMD_LIBXML_ERROR;
 969
 970     if (name && xmlStrEqual((xmlChar *)name, (xmlChar *)"_mtime"))
 971         return 0;
 972
 973     buf = g_strdup_printf("%li", time(NULL));
 974     rc = add_attribute(node, "_mtime", buf);
 975     g_free(buf);
 976     return rc;
 977 }
 978
 979 /*
 980  * From the element path 'path', find sub-nodes and append them to the list.
 981  */
 982 gpg_error_t create_path_list(xmlDocPtr doc, struct element_list_s *elements,
 983         gchar *path)
 984 {
 985     gpg_error_t rc;
 986     gchar **req, **req_orig;
 987     xmlNodePtr n;
 988     gboolean a_target = FALSE;
 989
 990     req = split_input_line(path, "\t", 0);
 991
 992     if (!req) {
 993         req = split_input_line(path, " ", 0);
 994
 995         if (!req)
 996             return GPG_ERR_SYNTAX;
 997     }
 998
 999     req_orig = g_strdupv(req);
1000
1001     if (!req_orig) {
1002         rc = gpg_err_code_from_errno(ENOMEM);
1003         goto fail;
1004     }
1005
1006     n = find_root_element(doc, &req, &rc, &a_target, 0, FALSE);
1007
1008     if (!n && rc == GPG_ERR_ELEMENT_NOT_FOUND && elements->resolving == TRUE) {
1009         rc = 0;
1010         goto fail;
1011     }
1012     else if (!n)
1013         goto fail;
1014
1015     if (a_target == TRUE) {
1016         g_free(*req);
1017         *req = g_strdup(*req_orig);
1018     }
1019
1020     if (*(req+1)) {
1021         gboolean e_target = FALSE;
1022
1023         n = find_elements(doc, n->children, req+1, &rc, &e_target, NULL, NULL, TRUE, 0, NULL, FALSE);
1024
1025         if (!n && rc == GPG_ERR_ELEMENT_NOT_FOUND && elements->resolving == TRUE) {
1026             rc = 0;
1027             goto fail;
1028         }
1029         else if (!n)
1030             goto fail;
1031     }
1032
1033     if (!elements->prefix) {
1034         /*
1035          * FIXME
1036          *
1037          * If any req_orig element contains no target the element should be
1038          * prefixed with the literal character. Not really crucial if the
1039          * client isn't human because child elements are prefixed for the
1040          * current path. But may be confusing if editing by hand.
1041          */
1042         elements->prefix = g_strjoinv("\t", req_orig);
1043
1044         if (!elements->prefix) {
1045             rc = gpg_err_code_from_errno(ENOMEM);
1046             goto fail;
1047         }
1048
1049         if (elements->verbose) {
1050             if (strv_printf(&elements->elements, "%s%s", elements->prefix, find_element_node(n->children) ? " 1" : " 0") == FALSE) {
1051                 rc = gpg_err_code_from_errno(ENOMEM);
1052                 goto fail;
1053             }
1054         }
1055         else if (strv_printf(&elements->elements, "%s", elements->prefix) == FALSE) {
1056             rc = gpg_err_code_from_errno(ENOMEM);
1057             goto fail;
1058         }
1059
1060         if (update_element_list(elements) == FALSE) {
1061             rc = gpg_err_code_from_errno(ENOMEM);
1062             goto fail;
1063         }
1064     }
1065
1066     rc = path_list_recurse(doc, n->children, elements);
1067
1068 fail:
1069     if (req_orig)
1070         g_strfreev(req_orig);
1071
1072     g_strfreev(req);
1073     return rc;
1074 }
1075
1076 gpg_error_t recurse_xpath_nodeset(xmlDocPtr doc, xmlNodeSetPtr nodes,
1077         xmlChar *value, xmlBufferPtr *result, gboolean cmd, const xmlChar *attr)
1078 {
1079     gint i = value ? nodes->nodeNr - 1 : 0;
1080     xmlBufferPtr buf;
1081
1082     buf = xmlBufferCreate();
1083
1084     if (!buf)
1085         return gpg_err_code_from_errno(ENOMEM);
1086
1087     for (; value ? i >= 0 : i < nodes->nodeNr; value ? i-- : i++) {
1088         xmlNodePtr n = nodes->nodeTab[i];
1089         gpg_error_t rc;
1090
1091         if (!n)
1092             continue;
1093
1094         if (!value && !attr) {
1095             if (xmlNodeDump(buf, doc, n, 0, 0) == -1) {
1096                 *result = buf;
1097                 return EPWMD_LIBXML_ERROR;
1098             }
1099
1100             continue;
1101         }
1102
1103         if (!attr) {
1104             xmlNodeSetContent(n, value);
1105             rc = update_element_mtime(n);
1106
1107             if (rc)
1108                 return rc;
1109         }
1110         else {
1111             if (!cmd)
1112                 rc = add_attribute(n, (gchar *)attr, (gchar *)value);
1113             else
1114                 rc = delete_attribute(n, attr);
1115
1116             if (rc)
1117                 return rc;
1118         }
1119     }
1120
1121     *result = buf;
1122     return 0;
1123 }
1124
1125 static gpg_error_t convert_root_element(xmlNodePtr n)
1126 {
1127     xmlChar *a = xmlGetProp(n, (xmlChar *)"_name");
1128     gpg_error_t rc;
1129
1130     if (a) {
1131         xmlFree(a);
1132         xmlChar *t = xmlGetNodePath(n);
1133
1134         log_write(N_("An existing \"_name\" attribute already exists. Please rename this attribute before converting. Path is: %s"), t);
1135         xmlFree(t);
1136         return GPG_ERR_AMBIGUOUS_NAME;
1137     }
1138
1139     a = xmlGetProp(n, (xmlChar *)"name");
1140
1141     if (a) {
1142         rc = add_attribute(n, "_name", (gchar *)a);
1143         xmlFree(a);
1144
1145         if (rc)
1146             return rc;
1147
1148         rc = delete_attribute(n, (xmlChar *)"name");
1149
1150         if (rc)
1151             return rc;
1152
1153         xmlNodeSetName(n, (xmlChar *)"element");
1154     }
1155
1156     return 0;
1157 }
1158
1159 /* Updates the DTD and renames the root "accounts" and "account" elements. */
1160 gpg_error_t convert_xml(gchar **xml, goffset *len)
1161 {
1162     gpg_error_t rc = EPWMD_LIBXML_ERROR;
1163     xmlDocPtr doc, new = NULL;
1164     xmlNodePtr n;
1165
1166     doc = xmlReadMemory(*xml, *len, NULL, "UTF-8", XML_PARSE_NOBLANKS);
1167
1168     if (!doc)
1169         return EPWMD_LIBXML_ERROR;
1170
1171     gcry_free(*xml);
1172     *xml = NULL;
1173     n = xmlDocGetRootElement(doc);
1174     xmlNodeSetName(n, (xmlChar *)"pwmd");
1175
1176     for (n = n->children; n; n = n->next) {
1177         if (xmlStrEqual(n->name, (xmlChar *)"account")) {
1178             rc = convert_root_element(n);
1179
1180             if (rc) {
1181                 xmlFreeDoc(doc);
1182                 return rc;
1183             }
1184         }
1185     }
1186
1187     new = create_dtd();
1188
1189     if (!new)
1190         goto fail;
1191
1192     n = xmlDocGetRootElement(doc);
1193     xmlDocSetRootElement(new, n);
1194     xmlDocDumpMemory(new, (xmlChar **)xml, (gint *)len);
1195     xmlDocSetRootElement(new, xmlCopyNode(n, 0));
1196     rc = 0;
1197
1198 fail:
1199     if (new)
1200         xmlFreeDoc(new);
1201
1202     xmlFreeDoc(doc);
1203     return rc;
1204 }
1205
1206 gpg_error_t delete_attribute(xmlNodePtr n, const xmlChar *name)
1207 {
1208     xmlAttrPtr a;
1209
1210     if ((a = xmlHasProp(n, name)) == NULL)
1211         return GPG_ERR_NOT_FOUND;
1212
1213     if (xmlRemoveProp(a) == -1)
1214         return EPWMD_LIBXML_ERROR;
1215
1216     return update_element_mtime(n);
1217 }
1218
1219 static gpg_error_t convert_elements_recurse(xmlDocPtr doc, xmlNodePtr n,
1220         guint depth)
1221 {
1222     gpg_error_t rc;
1223
1224     depth++;
1225
1226     for (n = n->children; n; n = n->next) {
1227         if (n->type == XML_ELEMENT_NODE) {
1228             xmlChar *a = NULL;
1229
1230             if (depth > 1) {
1231                 if (xmlStrEqual(n->name, (xmlChar *)"element")) {
1232                     xmlChar *t = xmlGetNodePath(n);
1233
1234                     log_write(N_("An existing \"element\" already exists. Please rename this element before converting. Path is: %s"), t);
1235                     xmlFree(t);
1236                     return GPG_ERR_AMBIGUOUS_NAME;
1237                 }
1238
1239                 a = xmlGetProp(n, (xmlChar *)"_name");
1240
1241                 if (a) {
1242                     xmlFree(a);
1243                     xmlChar *t = xmlGetNodePath(n);
1244
1245                     log_write(N_("An existing \"_name\" attribute already exists. Please rename this attribute before converting. Path is: %s"), t);
1246                     xmlFree(t);
1247                     return GPG_ERR_AMBIGUOUS_NAME;
1248                 }
1249
1250                 xmlChar *tmp = xmlStrdup(n->name);
1251
1252                 if (!tmp)
1253                     return gpg_error_from_errno(ENOMEM);
1254
1255                 xmlNodeSetName(n, (xmlChar *)"element");
1256                 rc = add_attribute(n, "_name", (gchar *)tmp);
1257                 xmlFree(tmp);
1258
1259                 if (rc)
1260                     return rc;
1261             }
1262             else {
1263                 rc = convert_root_element(n);
1264
1265                 if (rc)
1266                     return rc;
1267             }
1268         }
1269
1270         if (n->children) {
1271             rc = convert_elements_recurse(doc, n, depth);
1272
1273             if (rc)
1274                 return rc;
1275         }
1276     }
1277
1278     return 0;
1279 }
1280
1281 /* Renames ALL elements to the new "element" name. Existing element names are
1282  * stored as an attribute "_name". This was introduced in pwmd 2.12 so
1283  * elements can contain common characters that the XML parser barfs on (an
1284  * email address for example. */
1285 gpg_error_t convert_elements(xmlDocPtr doc)
1286 {
1287     xmlNodePtr n = xmlDocGetRootElement(doc);
1288     gpg_error_t rc;
1289
1290     log_write(N_("Converting pre 2.12 data file..."));
1291     rc = convert_elements_recurse(doc, n, 0);
1292
1293     if (!rc)
1294         log_write(N_("Finished converting. Please SAVE to update."));
1295
1296     return rc;
1297 }
1298
1299 gpg_error_t validate_import(xmlNodePtr node)
1300 {
1301     gpg_error_t rc;
1302
1303     if (!node)
1304         return 0;
1305
1306     for (xmlNodePtr n = node; n; n = n->next) {
1307         if (n->type == XML_ELEMENT_NODE) {
1308             if (xmlStrEqual(n->name, (xmlChar *)"element")) {
1309                 xmlChar *a = xmlGetProp(n, (xmlChar *)"_name");
1310
1311                 if (!a) {
1312                     xmlChar *t = xmlGetNodePath(n);
1313
1314                     log_write(N_("Missing attribute '_name' at %s."), t);
1315                     xmlFree(t);
1316                     return GPG_ERR_INV_VALUE;
1317                 }
1318
1319                 if (!valid_xml_element(a)) {
1320                     xmlChar *t = xmlGetNodePath(n);
1321
1322                     log_write(N_("'%s' is not a valid element name at %s."), a, t);
1323                     xmlFree(a);
1324                     xmlFree(t);
1325                     return GPG_ERR_INV_VALUE;
1326                 }
1327
1328                 xmlFree(a);
1329             }
1330             else {
1331                 xmlChar *t = xmlGetNodePath(n);
1332
1333                 log_write(N_("Warning: unknown element '%s' at %s. Ignoring."), n->name, t);
1334                 xmlFree(t);
1335                 continue;
1336             }
1337         }
1338
1339         if (n->children) {
1340             rc = validate_import(n->children);
1341
1342             if (rc)
1343                 return rc;
1344         }
1345     }
1346
1347     return rc;
1348 }
1349
1350 gpg_error_t update_element_mtime(xmlNodePtr n)
1351 {
1352     return add_attribute(n, NULL, NULL);
1353 }