summaryrefslogtreecommitdiffstats
path: root/libtdenetwork/libgpgme-copy/assuan/assuan-inquire.c
blob: d8c52d09ae7536352a20a31f9eeeefc13c6decb4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/* assuan-inquire.c - handle inquire stuff
 *	Copyright (C) 2001, 2002, 2003, 2005  Free Software Foundation, Inc.
 *
 * This file is part of Assuan.
 *
 * Assuan is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * Assuan is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA. 
 */

#include <config.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "assuan-defs.h"

#define digitp(a) ((a) >= '0' && (a) <= '9')
#define xtoi_1(p)   (*(p) <= '9'? (*(p)- '0'): \
                     *(p) <= 'F'? (*(p)-'A'+10):(*(p)-'a'+10))
#define xtoi_2(p)   ((xtoi_1(p) * 16) + xtoi_1((p)+1))


struct membuf
{
  size_t len;
  size_t size;
  char *buf;
  int out_of_core;
  int too_large;
  size_t maxlen;
};



/* A simple implemnation of a dynamic buffer.  Use init_membuf() to
   create a buffer, put_membuf to append bytes and get_membuf to
   release and return the buffer.  Allocation errors are detected but
   only returned at the final get_membuf(), this helps not to clutter
   the code with out of core checks.  */

static void
init_membuf (struct membuf *mb, int initiallen, size_t maxlen)
{
  mb->len = 0;
  mb->size = initiallen;
  mb->out_of_core = 0;
  mb->too_large = 0;
  mb->maxlen = maxlen;
  /* we need to allocate one byte more for get_membuf */
  mb->buf = xtrymalloc (initiallen+1);
  if (!mb->buf)
      mb->out_of_core = 1;
}

static void
put_membuf (struct membuf *mb, const void *buf, size_t len)
{
  if (mb->out_of_core || mb->too_large)
    return;

  if (mb->maxlen && mb->len + len > mb->maxlen)
    {
      mb->too_large = 1;
      return;
    }

  if (mb->len + len >= mb->size)
    {
      char *p;
      
      mb->size += len + 1024;
      /* we need to allocate one byte more for get_membuf */
      p = xtryrealloc (mb->buf, mb->size+1);
      if (!p)
        {
          mb->out_of_core = 1;
          return;
        }
      mb->buf = p;
    }
  memcpy (mb->buf + mb->len, buf, len);
  mb->len += len;
}

static void *
get_membuf (struct membuf *mb, size_t *len)
{
  char *p;

  if (mb->out_of_core || mb->too_large)
    {
      xfree (mb->buf);
      mb->buf = NULL;
      return NULL;
    }

  mb->buf[mb->len] = 0; /* there is enough space for the hidden eos */
  p = mb->buf;
  *len = mb->len;
  mb->buf = NULL;
  mb->out_of_core = 1; /* don't allow a reuse */
  return p;
}

static void
free_membuf (struct membuf *mb)
{
  xfree (mb->buf);
  mb->buf = NULL;
}


/**
 * assuan_inquire:
 * @ctx: An assuan context
 * @keyword: The keyword used for the inquire
 * @r_buffer: Returns an allocated buffer
 * @r_length: Returns the length of this buffer
 * @maxlen: If not 0, the size limit of the inquired data.
 * 
 * A Server may use this to Send an inquire.  r_buffer, r_length and
 * maxlen may all be NULL/0 to indicate that no real data is expected.
 * 
 * Return value: 0 on success or an ASSUAN error code
 **/
assuan_error_t
assuan_inquire (assuan_context_t ctx, const char *keyword,
                unsigned char **r_buffer, size_t *r_length, size_t maxlen)
{
  assuan_error_t rc;
  struct membuf mb;
  char cmdbuf[LINELENGTH-10]; /* (10 = strlen ("INQUIRE ")+CR,LF) */
  unsigned char *line, *p;
  int linelen;
  int nodataexpected;

  if (!ctx || !keyword || (10 + strlen (keyword) >= sizeof (cmdbuf)))
    return _assuan_error (ASSUAN_Invalid_Value);
  nodataexpected = !r_buffer && !r_length && !maxlen;
  if (!nodataexpected && (!r_buffer || !r_length))
    return _assuan_error (ASSUAN_Invalid_Value);
  if (!ctx->is_server)
    return _assuan_error (ASSUAN_Not_A_Server);
  if (ctx->in_inquire)
    return _assuan_error (ASSUAN_Nested_Commands);
  
  ctx->in_inquire = 1;
  if (nodataexpected)
    memset (&mb, 0, sizeof mb); /* avoid compiler warnings */
  else
    init_membuf (&mb, maxlen? maxlen:1024, maxlen);

  strcpy (stpcpy (cmdbuf, "INQUIRE "), keyword);
  rc = assuan_write_line (ctx, cmdbuf);
  if (rc)
    goto leave;

  for (;;)
    {
      do 
        {
          rc = _assuan_read_line (ctx);
          if (rc)
            goto leave;
          line = (unsigned char *) ctx->inbound.line;
          linelen = ctx->inbound.linelen;
        }    
      while (*line == '#' || !linelen);
      if (line[0] == 'E' && line[1] == 'N' && line[2] == 'D'
          && (!line[3] || line[3] == ' '))
        break; /* END command received*/
      if (line[0] == 'C' && line[1] == 'A' && line[2] == 'N')
        {
          rc = _assuan_error (ASSUAN_Canceled);
          goto leave;
        }
      if (line[0] != 'D' || line[1] != ' ' || nodataexpected)
        {
          rc = _assuan_error (ASSUAN_Unexpected_Command);
          goto leave;
        }
      if (linelen < 3)
        continue;
      line += 2;
      linelen -= 2;

      p = line;
      while (linelen)
        {
          for (;linelen && *p != '%'; linelen--, p++)
            ;
          put_membuf (&mb, line, p-line);
          if (linelen > 2)
            { /* handle escaping */
              unsigned char tmp[1];
              p++;
              *tmp = xtoi_2 (p);
              p += 2;
              linelen -= 3;
              put_membuf (&mb, tmp, 1);
            }
          line = p;
        }
      if (mb.too_large)
        {
          rc = _assuan_error (ASSUAN_Too_Much_Data);
          goto leave;
        }
    }

  if (!nodataexpected)
    {
      *r_buffer = get_membuf (&mb, r_length);
      if (!*r_buffer)
        rc = _assuan_error (ASSUAN_Out_Of_Core);
    }

 leave:
  if (!nodataexpected)
    free_membuf (&mb);
  ctx->in_inquire = 0;
  return rc;
}