1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22#include "server_setup.h"
23
24#include "getpart.h"
25
26#define ENABLE_CURLX_PRINTF
27/* make the curlx header define all printf() functions to use the curlx_*
28   versions instead */
29#include "curlx.h" /* from the private lib dir */
30
31/* just to please curl_base64.h we create a fake struct */
32struct Curl_easy {
33  int fake;
34};
35
36#include "curl_base64.h"
37#include "curl_memory.h"
38
39/* include memdebug.h last */
40#include "memdebug.h"
41
42#define EAT_SPACE(p) while(*(p) && ISSPACE(*(p))) (p)++
43
44#define EAT_WORD(p)  while(*(p) && !ISSPACE(*(p)) && ('>' != *(p))) (p)++
45
46#ifdef DEBUG_GETPART
47#define show(x) printf x
48#else
49#define show(x) Curl_nop_stmt
50#endif
51
52#if defined(_MSC_VER) && defined(_DLL)
53#  pragma warning(disable:4232) /* MSVC extension, dllimport identity */
54#endif
55
56curl_malloc_callback Curl_cmalloc = (curl_malloc_callback)malloc;
57curl_free_callback Curl_cfree = (curl_free_callback)free;
58curl_realloc_callback Curl_crealloc = (curl_realloc_callback)realloc;
59curl_strdup_callback Curl_cstrdup = (curl_strdup_callback)strdup;
60curl_calloc_callback Curl_ccalloc = (curl_calloc_callback)calloc;
61#if defined(WIN32) && defined(UNICODE)
62curl_wcsdup_callback Curl_cwcsdup = (curl_wcsdup_callback)_wcsdup;
63#endif
64
65#if defined(_MSC_VER) && defined(_DLL)
66#  pragma warning(default:4232) /* MSVC extension, dllimport identity */
67#endif
68
69/*
70 * readline()
71 *
72 * Reads a complete line from a file into a dynamically allocated buffer.
73 *
74 * Calling function may call this multiple times with same 'buffer'
75 * and 'bufsize' pointers to avoid multiple buffer allocations. Buffer
76 * will be reallocated and 'bufsize' increased until whole line fits in
77 * buffer before returning it.
78 *
79 * Calling function is responsible to free allocated buffer.
80 *
81 * This function may return:
82 *   GPE_OUT_OF_MEMORY
83 *   GPE_END_OF_FILE
84 *   GPE_OK
85 */
86
87static int readline(char **buffer, size_t *bufsize, FILE *stream)
88{
89  size_t offset = 0;
90  size_t length;
91  char *newptr;
92
93  if(!*buffer) {
94    *buffer = malloc(128);
95    if(!*buffer)
96      return GPE_OUT_OF_MEMORY;
97    *bufsize = 128;
98  }
99
100  for(;;) {
101    int bytestoread = curlx_uztosi(*bufsize - offset);
102
103    if(!fgets(*buffer + offset, bytestoread, stream))
104      return (offset != 0) ? GPE_OK : GPE_END_OF_FILE;
105
106    length = offset + strlen(*buffer + offset);
107    if(*(*buffer + length - 1) == '\n')
108      break;
109    offset = length;
110    if(length < *bufsize - 1)
111      continue;
112
113    newptr = realloc(*buffer, *bufsize * 2);
114    if(!newptr)
115      return GPE_OUT_OF_MEMORY;
116    *buffer = newptr;
117    *bufsize *= 2;
118  }
119
120  return GPE_OK;
121}
122
123/*
124 * appenddata()
125 *
126 * This appends data from a given source buffer to the end of the used part of
127 * a destination buffer. Arguments relative to the destination buffer are, the
128 * address of a pointer to the destination buffer 'dst_buf', the length of data
129 * in destination buffer excluding potential null string termination 'dst_len',
130 * the allocated size of destination buffer 'dst_alloc'. All three destination
131 * buffer arguments may be modified by this function. Arguments relative to the
132 * source buffer are, a pointer to the source buffer 'src_buf' and indication
133 * whether the source buffer is base64 encoded or not 'src_b64'.
134 *
135 * If the source buffer is indicated to be base64 encoded, this appends the
136 * decoded data, binary or whatever, to the destination. The source buffer
137 * may not hold binary data, only a null terminated string is valid content.
138 *
139 * Destination buffer will be enlarged and relocated as needed.
140 *
141 * Calling function is responsible to provide preallocated destination
142 * buffer and also to deallocate it when no longer needed.
143 *
144 * This function may return:
145 *   GPE_OUT_OF_MEMORY
146 *   GPE_OK
147 */
148
149static int appenddata(char  **dst_buf,   /* dest buffer */
150                      size_t *dst_len,   /* dest buffer data length */
151                      size_t *dst_alloc, /* dest buffer allocated size */
152                      char   *src_buf,   /* source buffer */
153                      int     src_b64)   /* != 0 if source is base64 encoded */
154{
155  size_t need_alloc = 0;
156  size_t src_len = strlen(src_buf);
157
158  if(!src_len)
159    return GPE_OK;
160
161  need_alloc = src_len + *dst_len + 1;
162
163  if(src_b64) {
164    if(src_buf[src_len - 1] == '\r')
165      src_len--;
166
167    if(src_buf[src_len - 1] == '\n')
168      src_len--;
169  }
170
171  /* enlarge destination buffer if required */
172  if(need_alloc > *dst_alloc) {
173    size_t newsize = need_alloc * 2;
174    char *newptr = realloc(*dst_buf, newsize);
175    if(!newptr) {
176      return GPE_OUT_OF_MEMORY;
177    }
178    *dst_alloc = newsize;
179    *dst_buf = newptr;
180  }
181
182  /* memcpy to support binary blobs */
183  memcpy(*dst_buf + *dst_len, src_buf, src_len);
184  *dst_len += src_len;
185  *(*dst_buf + *dst_len) = '\0';
186
187  return GPE_OK;
188}
189
190static int decodedata(char  **buf,   /* dest buffer */
191                      size_t *len)   /* dest buffer data length */
192{
193  int error = 0;
194  unsigned char *buf64 = NULL;
195  size_t src_len = 0;
196
197  if(!*len)
198    return GPE_OK;
199
200  /* base64 decode the given buffer */
201  error = (int) Curl_base64_decode(*buf, &buf64, &src_len);
202  if(error)
203    return GPE_OUT_OF_MEMORY;
204
205  if(!src_len) {
206    /*
207    ** currently there is no way to tell apart an OOM condition in
208    ** Curl_base64_decode() from zero length decoded data. For now,
209    ** let's just assume it is an OOM condition, currently we have
210    ** no input for this function that decodes to zero length data.
211    */
212    free(buf64);
213
214    return GPE_OUT_OF_MEMORY;
215  }
216
217  /* memcpy to support binary blobs */
218  memcpy(*buf, buf64, src_len);
219  *len = src_len;
220  *(*buf + src_len) = '\0';
221
222  free(buf64);
223
224  return GPE_OK;
225}
226
227/*
228 * getpart()
229 *
230 * This returns whole contents of specified XML-like section and subsection
231 * from the given file. This is mostly used to retrieve a specific part from
232 * a test definition file for consumption by test suite servers.
233 *
234 * Data is returned in a dynamically allocated buffer, a pointer to this data
235 * and the size of the data is stored at the addresses that caller specifies.
236 *
237 * If the returned data is a string the returned size will be the length of
238 * the string excluding null termination. Otherwise it will just be the size
239 * of the returned binary data.
240 *
241 * Calling function is responsible to free returned buffer.
242 *
243 * This function may return:
244 *   GPE_NO_BUFFER_SPACE
245 *   GPE_OUT_OF_MEMORY
246 *   GPE_OK
247 */
248
249int getpart(char **outbuf, size_t *outlen,
250            const char *main, const char *sub, FILE *stream)
251{
252# define MAX_TAG_LEN 79
253  char couter[MAX_TAG_LEN+1]; /* current outermost section */
254  char cmain[MAX_TAG_LEN+1];  /* current main section */
255  char csub[MAX_TAG_LEN+1];   /* current sub section */
256  char ptag[MAX_TAG_LEN+1];   /* potential tag */
257  char patt[MAX_TAG_LEN+1];   /* potential attributes */
258  char *buffer = NULL;
259  char *ptr;
260  char *end;
261  union {
262    ssize_t sig;
263     size_t uns;
264  } len;
265  size_t bufsize = 0;
266  size_t outalloc = 256;
267  int in_wanted_part = 0;
268  int base64 = 0;
269  int error;
270
271  enum {
272    STATE_OUTSIDE = 0,
273    STATE_OUTER   = 1,
274    STATE_INMAIN  = 2,
275    STATE_INSUB   = 3,
276    STATE_ILLEGAL = 4
277  } state = STATE_OUTSIDE;
278
279  *outlen = 0;
280  *outbuf = malloc(outalloc);
281  if(!*outbuf)
282    return GPE_OUT_OF_MEMORY;
283  *(*outbuf) = '\0';
284
285  couter[0] = cmain[0] = csub[0] = ptag[0] = patt[0] = '\0';
286
287  while((error = readline(&buffer, &bufsize, stream)) == GPE_OK) {
288
289    ptr = buffer;
290    EAT_SPACE(ptr);
291
292    if('<' != *ptr) {
293      if(in_wanted_part) {
294        show(("=> %s", buffer));
295        error = appenddata(outbuf, outlen, &outalloc, buffer, base64);
296        if(error)
297          break;
298      }
299      continue;
300    }
301
302    ptr++;
303
304    if('/' == *ptr) {
305      /*
306      ** closing section tag
307      */
308
309      ptr++;
310      end = ptr;
311      EAT_WORD(end);
312      if((len.sig = end - ptr) > MAX_TAG_LEN) {
313        error = GPE_NO_BUFFER_SPACE;
314        break;
315      }
316      memcpy(ptag, ptr, len.uns);
317      ptag[len.uns] = '\0';
318
319      if((STATE_INSUB == state) && !strcmp(csub, ptag)) {
320        /* end of current sub section */
321        state = STATE_INMAIN;
322        csub[0] = '\0';
323        if(in_wanted_part) {
324          /* end of wanted part */
325          in_wanted_part = 0;
326
327          /* Do we need to base64 decode the data? */
328          if(base64) {
329            error = decodedata(outbuf, outlen);
330            if(error)
331              return error;
332          }
333          break;
334        }
335      }
336      else if((STATE_INMAIN == state) && !strcmp(cmain, ptag)) {
337        /* end of current main section */
338        state = STATE_OUTER;
339        cmain[0] = '\0';
340        if(in_wanted_part) {
341          /* end of wanted part */
342          in_wanted_part = 0;
343
344          /* Do we need to base64 decode the data? */
345          if(base64) {
346            error = decodedata(outbuf, outlen);
347            if(error)
348              return error;
349          }
350          break;
351        }
352      }
353      else if((STATE_OUTER == state) && !strcmp(couter, ptag)) {
354        /* end of outermost file section */
355        state = STATE_OUTSIDE;
356        couter[0] = '\0';
357        if(in_wanted_part) {
358          /* end of wanted part */
359          in_wanted_part = 0;
360          break;
361        }
362      }
363
364    }
365    else if(!in_wanted_part) {
366      /*
367      ** opening section tag
368      */
369
370      /* get potential tag */
371      end = ptr;
372      EAT_WORD(end);
373      if((len.sig = end - ptr) > MAX_TAG_LEN) {
374        error = GPE_NO_BUFFER_SPACE;
375        break;
376      }
377      memcpy(ptag, ptr, len.uns);
378      ptag[len.uns] = '\0';
379
380      /* ignore comments, doctypes and xml declarations */
381      if(('!' == ptag[0]) || ('?' == ptag[0])) {
382        show(("* ignoring (%s)", buffer));
383        continue;
384      }
385
386      /* get all potential attributes */
387      ptr = end;
388      EAT_SPACE(ptr);
389      end = ptr;
390      while(*end && ('>' != *end))
391        end++;
392      if((len.sig = end - ptr) > MAX_TAG_LEN) {
393        error = GPE_NO_BUFFER_SPACE;
394        break;
395      }
396      memcpy(patt, ptr, len.uns);
397      patt[len.uns] = '\0';
398
399      if(STATE_OUTSIDE == state) {
400        /* outermost element (<testcase>) */
401        strcpy(couter, ptag);
402        state = STATE_OUTER;
403        continue;
404      }
405      else if(STATE_OUTER == state) {
406        /* start of a main section */
407        strcpy(cmain, ptag);
408        state = STATE_INMAIN;
409        continue;
410      }
411      else if(STATE_INMAIN == state) {
412        /* start of a sub section */
413        strcpy(csub, ptag);
414        state = STATE_INSUB;
415        if(!strcmp(cmain, main) && !strcmp(csub, sub)) {
416          /* start of wanted part */
417          in_wanted_part = 1;
418          if(strstr(patt, "base64="))
419              /* bit rough test, but "mostly" functional, */
420              /* treat wanted part data as base64 encoded */
421              base64 = 1;
422        }
423        continue;
424      }
425
426    }
427
428    if(in_wanted_part) {
429      show(("=> %s", buffer));
430      error = appenddata(outbuf, outlen, &outalloc, buffer, base64);
431      if(error)
432        break;
433    }
434
435  } /* while */
436
437  free(buffer);
438
439  if(error != GPE_OK) {
440    if(error == GPE_END_OF_FILE)
441      error = GPE_OK;
442    else {
443      free(*outbuf);
444      *outbuf = NULL;
445      *outlen = 0;
446    }
447  }
448
449  return error;
450}
451
452