xref: /openbsd-src/lib/libcrypto/ocsp/ocsp_ht.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
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 
76 struct 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 
110 static int parse_http_line1(char *line);
111 
112 void 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 
121 OCSP_REQ_CTX *OCSP_sendreq_new(BIO *io, char *path, OCSP_REQUEST *req,
122 								int maxline)
123 	{
124 	static char post_hdr[] = "POST %s HTTP/1.0\r\n"
125 	"Content-Type: application/ocsp-request\r\n"
126 	"Content-Length: %d\r\n\r\n";
127 
128 	OCSP_REQ_CTX *rctx;
129 	rctx = OPENSSL_malloc(sizeof(OCSP_REQ_CTX));
130 	rctx->state = OHS_FIRSTLINE;
131 	rctx->mem = BIO_new(BIO_s_mem());
132 	rctx->io = io;
133 	if (maxline > 0)
134 		rctx->iobuflen = maxline;
135 	else
136 		rctx->iobuflen = OCSP_MAX_LINE_LEN;
137 	rctx->iobuf = OPENSSL_malloc(rctx->iobuflen);
138 	if (!path)
139 		path = "/";
140 
141         if (BIO_printf(rctx->mem, post_hdr, path,
142 				i2d_OCSP_REQUEST(req, NULL)) <= 0)
143 		{
144 		rctx->state = OHS_ERROR;
145 		return 0;
146 		}
147         if (i2d_OCSP_REQUEST_bio(rctx->mem, req) <= 0)
148 		{
149 		rctx->state = OHS_ERROR;
150 		return 0;
151 		}
152 	rctx->state = OHS_ASN1_WRITE;
153 	rctx->asn1_len = BIO_get_mem_data(rctx->mem, NULL);
154 
155 	return rctx;
156 	}
157 
158 /* Parse the HTTP response. This will look like this:
159  * "HTTP/1.0 200 OK". We need to obtain the numeric code and
160  * (optional) informational message.
161  */
162 
163 static int parse_http_line1(char *line)
164 	{
165 	int retcode;
166 	char *p, *q, *r;
167 	/* Skip to first white space (passed protocol info) */
168 
169 	for(p = line; *p && !isspace((unsigned char)*p); p++)
170 		continue;
171 	if(!*p)
172 		{
173 		OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
174 					OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
175 		return 0;
176 		}
177 
178 	/* Skip past white space to start of response code */
179 	while(*p && isspace((unsigned char)*p))
180 		p++;
181 
182 	if(!*p)
183 		{
184 		OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
185 					OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
186 		return 0;
187 		}
188 
189 	/* Find end of response code: first whitespace after start of code */
190 	for(q = p; *q && !isspace((unsigned char)*q); q++)
191 		continue;
192 
193 	if(!*q)
194 		{
195 		OCSPerr(OCSP_F_PARSE_HTTP_LINE1,
196 					OCSP_R_SERVER_RESPONSE_PARSE_ERROR);
197 		return 0;
198 		}
199 
200 	/* Set end of response code and start of message */
201 	*q++ = 0;
202 
203 	/* Attempt to parse numeric code */
204 	retcode = strtoul(p, &r, 10);
205 
206 	if(*r)
207 		return 0;
208 
209 	/* Skip over any leading white space in message */
210 	while(*q && isspace((unsigned char)*q))
211 		q++;
212 
213 	if(*q)
214 		{
215 		/* Finally zap any trailing white space in message (include
216 		 * CRLF) */
217 
218 		/* We know q has a non white space character so this is OK */
219 		for(r = q + strlen(q) - 1; isspace((unsigned char)*r); r--)
220 			*r = 0;
221 		}
222 	if(retcode != 200)
223 		{
224 		OCSPerr(OCSP_F_PARSE_HTTP_LINE1, OCSP_R_SERVER_RESPONSE_ERROR);
225 		if(!*q)
226 			ERR_add_error_data(2, "Code=", p);
227 		else
228 			ERR_add_error_data(4, "Code=", p, ",Reason=", q);
229 		return 0;
230 		}
231 
232 
233 	return 1;
234 
235 	}
236 
237 int OCSP_sendreq_nbio(OCSP_RESPONSE **presp, OCSP_REQ_CTX *rctx)
238 	{
239 	int i, n;
240 	const unsigned char *p;
241 	next_io:
242 	if (!(rctx->state & OHS_NOREAD))
243 		{
244 		n = BIO_read(rctx->io, rctx->iobuf, rctx->iobuflen);
245 
246 		if (n <= 0)
247 			{
248 			if (BIO_should_retry(rctx->io))
249 				return -1;
250 			return 0;
251 			}
252 
253 		/* Write data to memory BIO */
254 
255 		if (BIO_write(rctx->mem, rctx->iobuf, n) != n)
256 			return 0;
257 		}
258 
259 	switch(rctx->state)
260 		{
261 
262 		case OHS_ASN1_WRITE:
263 		n = BIO_get_mem_data(rctx->mem, &p);
264 
265 		i = BIO_write(rctx->io,
266 			p + (n - rctx->asn1_len), rctx->asn1_len);
267 
268 		if (i <= 0)
269 			{
270 			if (BIO_should_retry(rctx->io))
271 				return -1;
272 			rctx->state = OHS_ERROR;
273 			return 0;
274 			}
275 
276 		rctx->asn1_len -= i;
277 
278 		if (rctx->asn1_len > 0)
279 			goto next_io;
280 
281 		rctx->state = OHS_ASN1_FLUSH;
282 
283 		(void)BIO_reset(rctx->mem);
284 
285 		case OHS_ASN1_FLUSH:
286 
287 		i = BIO_flush(rctx->io);
288 
289 		if (i > 0)
290 			{
291 			rctx->state = OHS_FIRSTLINE;
292 			goto next_io;
293 			}
294 
295 		if (BIO_should_retry(rctx->io))
296 			return -1;
297 
298 		rctx->state = OHS_ERROR;
299 		return 0;
300 
301 		case OHS_ERROR:
302 		return 0;
303 
304 		case OHS_FIRSTLINE:
305 		case OHS_HEADERS:
306 
307 		/* Attempt to read a line in */
308 
309 		next_line:
310 		/* Due to &%^*$" memory BIO behaviour with BIO_gets we
311 		 * have to check there's a complete line in there before
312 		 * calling BIO_gets or we'll just get a partial read.
313 		 */
314 		n = BIO_get_mem_data(rctx->mem, &p);
315 		if ((n <= 0) || !memchr(p, '\n', n))
316 			{
317 			if (n >= rctx->iobuflen)
318 				{
319 				rctx->state = OHS_ERROR;
320 				return 0;
321 				}
322 			goto next_io;
323 			}
324 		n = BIO_gets(rctx->mem, (char *)rctx->iobuf, rctx->iobuflen);
325 
326 		if (n <= 0)
327 			{
328 			if (BIO_should_retry(rctx->mem))
329 				goto next_io;
330 			rctx->state = OHS_ERROR;
331 			return 0;
332 			}
333 
334 		/* Don't allow excessive lines */
335 		if (n == rctx->iobuflen)
336 			{
337 			rctx->state = OHS_ERROR;
338 			return 0;
339 			}
340 
341 		/* First line */
342 		if (rctx->state == OHS_FIRSTLINE)
343 			{
344 			if (parse_http_line1((char *)rctx->iobuf))
345 				{
346 				rctx->state = OHS_HEADERS;
347 				goto next_line;
348 				}
349 			else
350 				{
351 				rctx->state = OHS_ERROR;
352 				return 0;
353 				}
354 			}
355 		else
356 			{
357 			/* Look for blank line: end of headers */
358 			for (p = rctx->iobuf; *p; p++)
359 				{
360 				if ((*p != '\r') && (*p != '\n'))
361 					break;
362 				}
363 			if (*p)
364 				goto next_line;
365 
366 			rctx->state = OHS_ASN1_HEADER;
367 
368 			}
369 
370 		/* Fall thru */
371 
372 
373 		case OHS_ASN1_HEADER:
374 		/* Now reading ASN1 header: can read at least 6 bytes which
375 		 * is more than enough for any valid ASN1 SEQUENCE header
376 		 */
377 		n = BIO_get_mem_data(rctx->mem, &p);
378 		if (n < 6)
379 			goto next_io;
380 
381 		/* Check it is an ASN1 SEQUENCE */
382 		if (*p++ != (V_ASN1_SEQUENCE|V_ASN1_CONSTRUCTED))
383 			{
384 			rctx->state = OHS_ERROR;
385 			return 0;
386 			}
387 
388 		/* Check out length field */
389 		if (*p & 0x80)
390 			{
391 			n = *p & 0x7F;
392 			/* Not NDEF or excessive length */
393 			if (!n || (n > 4))
394 				{
395 				rctx->state = OHS_ERROR;
396 				return 0;
397 				}
398 			p++;
399 			rctx->asn1_len = 0;
400 			for (i = 0; i < n; i++)
401 				{
402 				rctx->asn1_len <<= 8;
403 				rctx->asn1_len |= *p++;
404 				}
405 
406 			if (rctx->asn1_len > OCSP_MAX_REQUEST_LENGTH)
407 				{
408 				rctx->state = OHS_ERROR;
409 				return 0;
410 				}
411 
412 			rctx->asn1_len += n + 2;
413 			}
414 		else
415 			rctx->asn1_len = *p + 2;
416 
417 		rctx->state = OHS_ASN1_CONTENT;
418 
419 		/* Fall thru */
420 
421 		case OHS_ASN1_CONTENT:
422 		n = BIO_get_mem_data(rctx->mem, &p);
423 		if (n < (int)rctx->asn1_len)
424 			goto next_io;
425 
426 
427 		*presp = d2i_OCSP_RESPONSE(NULL, &p, rctx->asn1_len);
428 		if (*presp)
429 			{
430 			rctx->state = OHS_DONE;
431 			return 1;
432 			}
433 
434 		rctx->state = OHS_ERROR;
435 		return 0;
436 
437 		break;
438 
439 		case OHS_DONE:
440 		return 1;
441 
442 		}
443 
444 
445 
446 	return 0;
447 
448 
449 	}
450 
451 /* Blocking OCSP request handler: now a special case of non-blocking I/O */
452 
453 OCSP_RESPONSE *OCSP_sendreq_bio(BIO *b, char *path, OCSP_REQUEST *req)
454 	{
455 	OCSP_RESPONSE *resp = NULL;
456 	OCSP_REQ_CTX *ctx;
457 	int rv;
458 
459 	ctx = OCSP_sendreq_new(b, path, req, -1);
460 
461 	do
462 		{
463 		rv = OCSP_sendreq_nbio(&resp, ctx);
464 		} while ((rv == -1) && BIO_should_retry(b));
465 
466 	OCSP_REQ_CTX_free(ctx);
467 
468 	if (rv)
469 		return resp;
470 
471 	return NULL;
472 	}
473