ocsp_ht.c revision 43c12e3d4f9bbbbd4a8ba7b149686437514bc6b6 
1/* ocsp_ht.c */
2/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project 2006.
4 */
5/* ====================================================================
6 * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    licensing@OpenSSL.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59#include <stdio.h>
60#include <stdlib.h>
61#include <ctype.h>
62#include <string.h>
63#include "e_os.h"
64#include <openssl/asn1.h>
65#include <openssl/ocsp.h>
66#include <openssl/err.h>
67#include <openssl/buffer.h>
68#ifdef OPENSSL_SYS_SUNOS
69#define strtoul (unsigned long)strtol
70#endif /* OPENSSL_SYS_SUNOS */
71
72/* Stateful OCSP request code, supporting non-blocking I/O */
73
74/* Opaque OCSP request status structure */
75
76struct ocsp_req_ctx_st {
77	int state;		/* Current I/O state */
78	unsigned char *iobuf;	/* Line buffer */
79	int iobuflen;		/* Line buffer length */
80	BIO *io;		/* BIO to perform I/O with */
81	BIO *mem;		/* Memory BIO response is built into */
82	unsigned long asn1_len;	/* ASN1 length of response */
83	};
84
85#define OCSP_MAX_REQUEST_LENGTH	(100 * 1024)
86#define OCSP_MAX_LINE_LEN	4096;
87
88/* OCSP states */
89
90/* If set no reading should be performed */
91#define OHS_NOREAD		0x1000
92/* Error condition */
93#define OHS_ERROR		(0 | OHS_NOREAD)
94/* First line being read */
95#define OHS_FIRSTLINE		1
96/* MIME headers being read */
97#define OHS_HEADERS		2
98/* OCSP initial header (tag + length) being read */
99#define OHS_ASN1_HEADER		3
100/* OCSP content octets being read */
101#define OHS_ASN1_CONTENT	4
102/* Request being sent */
103#define OHS_ASN1_WRITE		(6 | OHS_NOREAD)
104/* Request being flushed */
105#define OHS_ASN1_FLUSH		(7 | OHS_NOREAD)
106/* Completed */
107#define OHS_DONE		(8 | OHS_NOREAD)
108
109
110static int parse_http_line1(char *line);
111
112void OCSP_REQ_CTX_free(OCSP_REQ_CTX *rctx)
113	{
114	if (rctx->mem)
115		BIO_free(rctx->mem);
116	if (rctx->iobuf)
117		OPENSSL_free(rctx->iobuf);
118	OPENSSL_free(rctx);
119	}
120
121int OCSP_REQ_CTX_set1_req(OCSP_REQ_CTX *rctx, OCSP_REQUEST *req)
122	{
123	static const char req_hdr[] =
124	"Content-Type: application/ocsp-request\r\n"
125	"Content-Length: %d\r\n\r\n";
126        if (BIO_printf(rctx->mem, req_hdr, i2d_OCSP_REQUEST(req, NULL)) <= 0)
127		return 0;
128        if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0)
129		return 0;
130	rctx->state = OHS_ASN1_WRITE;
131	rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL);
132	return 1;
133	}
134
135int OCSP_REQ_CTX_add1_header(OCSP_REQ_CTX *rctx,
136		const char *name, const char *value)
137	{
138	if (!name)
139		return 0;
140	if (BIO_puts(rctx->mem, name) <= 0)
141		return 0;
142	if (value)
143		{
144		if (BIO_write(rctx->mem, ": ", 2) != 2)
145			return 0;
146		if (BIO_puts(rctx->mem, value) <= 0)
147			return 0;
148		}
149	if (BIO_write(rctx->mem, "\r\n", 2) != 2)
150		return 0;
151	return 1;
152	}
153
154OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req,
155								int maxline)
156	{
157	static const char post_hdr[] = "POST %s HTTP/1.0\r\n";
158
159	OCSP_REQ_CTX *rctx;
160	rctx = OPENSSL_malloc(sizeof(OCSP_REQ_CTX));
161	rctx->state = OHS_ERROR;
162	rctx->mem = BIO_new(BIO_s_mem());
163	rctx->io = io;
164	rctx->asn1_len = 0;
165	if (maxline > 0)
166		rctx->iobuflen = maxline;
167	else
168		rctx->iobuflen = OCSP_MAX_LINE_LEN;
169	rctx->iobuf = OPENSSL_malloc(rctx->iobuflen);
170	if (!rctx->iobuf)
171		return 0;
172	if (!path)
173		path = "/";
174
175        if (BIO_printf(rctx->mem, post_hdr, path) <= 0)
176		return 0;
177
178	if (req && !OCSP_REQ_CTX_set1_req(rctx, req))
179		return 0;
180
181	return rctx;
182	}
183
184/* Parse the HTTP response. This will look like this:
185 * "HTTP/1.0 200 OK". We need to obtain the numeric code and
186 * (optional) informational message.
187 */
188
189static int parse_http_line1(char *line)
190	{
191	int retcode;
192	char *p, *q, *r;
193	/* Skip to first white space (passed protocol info) */
194
195	for(p = line; *p && !isspace((unsigned char)*p); p++)
196		continue;
197	if(!*p)
198		{
199		OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
200					OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
201		return 0;
202		}
203
204	/* Skip past white space to start of response code */
205	while(*p && isspace((unsigned char)*p))
206		p++;
207
208	if(!*p)
209		{
210		OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
211					OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
212		return 0;
213		}
214
215	/* Find end of response code: first whitespace after start of code */
216	for(q = p; *q && !isspace((unsigned char)*q); q++)
217		continue;
218
219	if(!*q)
220		{
221		OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
222					OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
223		return 0;
224		}
225
226	/* Set end of response code and start of message */
227	*q++ = 0;
228
229	/* Attempt to parse numeric code */
230	retcode = strtoul(p, &r, 10);
231
232	if(*r)
233		return 0;
234
235	/* Skip over any leading white space in message */
236	while(*q && isspace((unsigned char)*q))
237		q++;
238
239	if(*q)
240		{
241		/* Finally zap any trailing white space in message (include
242		 * CRLF) */
243
244		/* We know q has a non white space character so this is OK */
245		for(r = q + strlen(q) - 1; isspace((unsigned char)*r); r--)
246			*r = 0;
247		}
248	if(retcode != 200)
249		{
250		OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR);
251		if(!*q)
252			ERR_add_error_data(2, "Code=", p);
253		else
254			ERR_add_error_data(4, "Code=", p, ",Reason=", q);
255		return 0;
256		}
257
258
259	return 1;
260
261	}
262
263int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx)
264	{
265	int i, n;
266	const unsigned char *p;
267	next_io:
268	if (!(rctx->state & OHS_NOREAD))
269		{
270		n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen);
271
272		if (n <= 0)
273			{
274			if (BIO_should_retry(rctx->io))
275				return -1;
276			return 0;
277			}
278
279		/* Write data to memory BIO */
280
281		if (BIO_write(rctx->mem, rctx->iobuf, n) != n)
282			return 0;
283		}
284
285	switch(rctx->state)
286		{
287
288		case OHS_ASN1_WRITE:
289		n = BIO_get_mem_data(rctx->mem, &p);
290
291		i = BIO_write(rctx->io,
292			p + (n - rctx->asn1_len), rctx->asn1_len);
293
294		if (i <= 0)
295			{
296			if (BIO_should_retry(rctx->io))
297				return -1;
298			rctx->state = OHS_ERROR;
299			return 0;
300			}
301
302		rctx->asn1_len -= i;
303
304		if (rctx->asn1_len > 0)
305			goto next_io;
306
307		rctx->state = OHS_ASN1_FLUSH;
308
309		(void)BIO_reset(rctx->mem);
310
311		case OHS_ASN1_FLUSH:
312
313		i = BIO_flush(rctx->io);
314
315		if (i > 0)
316			{
317			rctx->state = OHS_FIRSTLINE;
318			goto next_io;
319			}
320
321		if (BIO_should_retry(rctx->io))
322			return -1;
323
324		rctx->state = OHS_ERROR;
325		return 0;
326
327		case OHS_ERROR:
328		return 0;
329
330		case OHS_FIRSTLINE:
331		case OHS_HEADERS:
332
333		/* Attempt to read a line in */
334
335		next_line:
336		/* Due to &%^*$" memory BIO behaviour with BIO_gets we
337		 * have to check there's a complete line in there before
338		 * calling BIO_gets or we'll just get a partial read.
339		 */
340		n = BIO_get_mem_data(rctx->mem, &p);
341		if ((n <= 0) || !memchr(p, '\n', n))
342			{
343			if (n >= rctx->iobuflen)
344				{
345				rctx->state = OHS_ERROR;
346				return 0;
347				}
348			goto next_io;
349			}
350		n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen);
351
352		if (n <= 0)
353			{
354			if (BIO_should_retry(rctx->mem))
355				goto next_io;
356			rctx->state = OHS_ERROR;
357			return 0;
358			}
359
360		/* Don't allow excessive lines */
361		if (n == rctx->iobuflen)
362			{
363			rctx->state = OHS_ERROR;
364			return 0;
365			}
366
367		/* First line */
368		if (rctx->state == OHS_FIRSTLINE)
369			{
370			if (parse_http_line1((char *)rctx->iobuf))
371				{
372				rctx->state = OHS_HEADERS;
373				goto next_line;
374				}
375			else
376				{
377				rctx->state = OHS_ERROR;
378				return 0;
379				}
380			}
381		else
382			{
383			/* Look for blank line: end of headers */
384			for (p = rctx->iobuf; *p; p++)
385				{
386				if ((*p != '\r') && (*p != '\n'))
387					break;
388				}
389			if (*p)
390				goto next_line;
391
392			rctx->state = OHS_ASN1_HEADER;
393
394			}
395
396		/* Fall thru */
397
398
399		case OHS_ASN1_HEADER:
400		/* Now reading ASN1 header: can read at least 2 bytes which
401		 * is enough for ASN1 SEQUENCE header and either length field
402		 * or at least the length of the length field.
403		 */
404		n = BIO_get_mem_data(rctx->mem, &p);
405		if (n < 2)
406			goto next_io;
407
408		/* Check it is an ASN1 SEQUENCE */
409		if (*p++ != (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED))
410			{
411			rctx->state = OHS_ERROR;
412			return 0;
413			}
414
415		/* Check out length field */
416		if (*p & 0x80)
417			{
418			/* If MSB set on initial length octet we can now
419			 * always read 6 octets: make sure we have them.
420			 */
421			if (n < 6)
422				goto next_io;
423			n = *p & 0x7F;
424			/* Not NDEF or excessive length */
425			if (!n || (n > 4))
426				{
427				rctx->state = OHS_ERROR;
428				return 0;
429				}
430			p++;
431			rctx->asn1_len = 0;
432			for (i = 0; i < n; i++)
433				{
434				rctx->asn1_len <<= 8;
435				rctx->asn1_len |= *p++;
436				}
437
438			if (rctx->asn1_len > OCSP_MAX_REQUEST_LENGTH)
439				{
440				rctx->state = OHS_ERROR;
441				return 0;
442				}
443
444			rctx->asn1_len += n + 2;
445			}
446		else
447			rctx->asn1_len = *p + 2;
448
449		rctx->state = OHS_ASN1_CONTENT;
450
451		/* Fall thru */
452
453		case OHS_ASN1_CONTENT:
454		n = BIO_get_mem_data(rctx->mem, &p);
455		if (n < (int)rctx->asn1_len)
456			goto next_io;
457
458
459		*presp = d2i_OCSP_RESPONSE(NULL, &p, rctx->asn1_len);
460		if (*presp)
461			{
462			rctx->state = OHS_DONE;
463			return 1;
464			}
465
466		rctx->state = OHS_ERROR;
467		return 0;
468
469		break;
470
471		case OHS_DONE:
472		return 1;
473
474		}
475
476
477
478	return 0;
479
480
481	}
482
483/* Blocking OCSP request handler: now a special case of non-blocking I/O */
484
485OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req)
486	{
487	OCSP_RESPONSE *resp = NULL;
488	OCSP_REQ_CTX *ctx;
489	int rv;
490
491	ctx = OCSP_sendreq_new(b, path, req, -1);
492
493	do
494		{
495		rv = OCSP_sendreq_nbio(&resp, ctx);
496		} while ((rv == -1) && BIO_should_retry(b));
497
498	OCSP_REQ_CTX_free(ctx);
499
500	if (rv)
501		return resp;
502
503	return NULL;
504	}
505