1 /*
2  * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL licenses, (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  * https://www.openssl.org/source/license.html
8  * or in the file LICENSE in the source distribution.
9  */
10 
11 #include <string.h>
12 #include <openssl/ssl.h>
13 #include <openssl/bio.h>
14 #include <openssl/err.h>
15 
16 #include "../ssl/packet_locl.h"
17 
18 #include "ssltestlib.h"
19 #include "testutil.h"
20 
21 /* Should we fragment records or not? 0 = no, !0 = yes*/
22 static int fragment = 0;
23 
24 static char *cert = NULL;
25 static char *privkey = NULL;
26 
27 static int async_new(BIO *bi);
28 static int async_free(BIO *a);
29 static int async_read(BIO *b, char *out, int outl);
30 static int async_write(BIO *b, const char *in, int inl);
31 static long async_ctrl(BIO *b, int cmd, long num, void *ptr);
32 static int async_gets(BIO *bp, char *buf, int size);
33 static int async_puts(BIO *bp, const char *str);
34 
35 /* Choose a sufficiently large type likely to be unused for this custom BIO */
36 # define BIO_TYPE_ASYNC_FILTER  (0x80 | BIO_TYPE_FILTER)
37 
38 static BIO_METHOD *methods_async = NULL;
39 
40 struct async_ctrs {
41     unsigned int rctr;
42     unsigned int wctr;
43 };
44 
bio_f_async_filter(void)45 static const BIO_METHOD *bio_f_async_filter(void)
46 {
47     if (methods_async == NULL) {
48         methods_async = BIO_meth_new(BIO_TYPE_ASYNC_FILTER, "Async filter");
49         if (   methods_async == NULL
50             || !BIO_meth_set_write(methods_async, async_write)
51             || !BIO_meth_set_read(methods_async, async_read)
52             || !BIO_meth_set_puts(methods_async, async_puts)
53             || !BIO_meth_set_gets(methods_async, async_gets)
54             || !BIO_meth_set_ctrl(methods_async, async_ctrl)
55             || !BIO_meth_set_create(methods_async, async_new)
56             || !BIO_meth_set_destroy(methods_async, async_free))
57             return NULL;
58     }
59     return methods_async;
60 }
61 
async_new(BIO * bio)62 static int async_new(BIO *bio)
63 {
64     struct async_ctrs *ctrs;
65 
66     ctrs = OPENSSL_zalloc(sizeof(struct async_ctrs));
67     if (ctrs == NULL)
68         return 0;
69 
70     BIO_set_data(bio, ctrs);
71     BIO_set_init(bio, 1);
72     return 1;
73 }
74 
async_free(BIO * bio)75 static int async_free(BIO *bio)
76 {
77     struct async_ctrs *ctrs;
78 
79     if (bio == NULL)
80         return 0;
81     ctrs = BIO_get_data(bio);
82     OPENSSL_free(ctrs);
83     BIO_set_data(bio, NULL);
84     BIO_set_init(bio, 0);
85 
86     return 1;
87 }
88 
async_read(BIO * bio,char * out,int outl)89 static int async_read(BIO *bio, char *out, int outl)
90 {
91     struct async_ctrs *ctrs;
92     int ret = 0;
93     BIO *next = BIO_next(bio);
94 
95     if (outl <= 0)
96         return 0;
97     if (next == NULL)
98         return 0;
99 
100     ctrs = BIO_get_data(bio);
101 
102     BIO_clear_retry_flags(bio);
103 
104     if (ctrs->rctr > 0) {
105         ret = BIO_read(next, out, 1);
106         if (ret <= 0 && BIO_should_read(next))
107             BIO_set_retry_read(bio);
108         ctrs->rctr = 0;
109     } else {
110         ctrs->rctr++;
111         BIO_set_retry_read(bio);
112     }
113 
114     return ret;
115 }
116 
117 #define MIN_RECORD_LEN  6
118 
119 #define CONTENTTYPEPOS  0
120 #define VERSIONHIPOS    1
121 #define VERSIONLOPOS    2
122 #define DATAPOS         5
123 
async_write(BIO * bio,const char * in,int inl)124 static int async_write(BIO *bio, const char *in, int inl)
125 {
126     struct async_ctrs *ctrs;
127     int ret = 0;
128     size_t written = 0;
129     BIO *next = BIO_next(bio);
130 
131     if (inl <= 0)
132         return 0;
133     if (next == NULL)
134         return 0;
135 
136     ctrs = BIO_get_data(bio);
137 
138     BIO_clear_retry_flags(bio);
139 
140     if (ctrs->wctr > 0) {
141         ctrs->wctr = 0;
142         if (fragment) {
143             PACKET pkt;
144 
145             if (!PACKET_buf_init(&pkt, (const unsigned char *)in, inl))
146                 return -1;
147 
148             while (PACKET_remaining(&pkt) > 0) {
149                 PACKET payload, wholebody, sessionid, extensions;
150                 unsigned int contenttype, versionhi, versionlo, data;
151                 unsigned int msgtype = 0, negversion = 0;
152 
153                 if (!PACKET_get_1(&pkt, &contenttype)
154                         || !PACKET_get_1(&pkt, &versionhi)
155                         || !PACKET_get_1(&pkt, &versionlo)
156                         || !PACKET_get_length_prefixed_2(&pkt, &payload))
157                     return -1;
158 
159                 /* Pretend we wrote out the record header */
160                 written += SSL3_RT_HEADER_LENGTH;
161 
162                 wholebody = payload;
163                 if (contenttype == SSL3_RT_HANDSHAKE
164                         && !PACKET_get_1(&wholebody, &msgtype))
165                     return -1;
166 
167                 if (msgtype == SSL3_MT_SERVER_HELLO) {
168                     if (!PACKET_forward(&wholebody,
169                                             SSL3_HM_HEADER_LENGTH - 1)
170                             || !PACKET_get_net_2(&wholebody, &negversion)
171                                /* Skip random (32 bytes) */
172                             || !PACKET_forward(&wholebody, 32)
173                                /* Skip session id */
174                             || !PACKET_get_length_prefixed_1(&wholebody,
175                                                              &sessionid)
176                                /*
177                                 * Skip ciphersuite (2 bytes) and compression
178                                 * method (1 byte)
179                                 */
180                             || !PACKET_forward(&wholebody, 2 + 1)
181                             || !PACKET_get_length_prefixed_2(&wholebody,
182                                                              &extensions))
183                         return -1;
184 
185                     /*
186                      * Find the negotiated version in supported_versions
187                      * extension, if present.
188                      */
189                     while (PACKET_remaining(&extensions)) {
190                         unsigned int type;
191                         PACKET extbody;
192 
193                         if (!PACKET_get_net_2(&extensions, &type)
194                                 || !PACKET_get_length_prefixed_2(&extensions,
195                                 &extbody))
196                             return -1;
197 
198                         if (type == TLSEXT_TYPE_supported_versions
199                                 && (!PACKET_get_net_2(&extbody, &negversion)
200                                     || PACKET_remaining(&extbody) != 0))
201                             return -1;
202                     }
203                 }
204 
205                 while (PACKET_get_1(&payload, &data)) {
206                     /* Create a new one byte long record for each byte in the
207                      * record in the input buffer
208                      */
209                     char smallrec[MIN_RECORD_LEN] = {
210                         0, /* Content type */
211                         0, /* Version hi */
212                         0, /* Version lo */
213                         0, /* Length hi */
214                         1, /* Length lo */
215                         0  /* Data */
216                     };
217 
218                     smallrec[CONTENTTYPEPOS] = contenttype;
219                     smallrec[VERSIONHIPOS] = versionhi;
220                     smallrec[VERSIONLOPOS] = versionlo;
221                     smallrec[DATAPOS] = data;
222                     ret = BIO_write(next, smallrec, MIN_RECORD_LEN);
223                     if (ret <= 0)
224                         return -1;
225                     written++;
226                 }
227                 /*
228                  * We can't fragment anything after the ServerHello (or CCS <=
229                  * TLS1.2), otherwise we get a bad record MAC
230                  */
231                 if (contenttype == SSL3_RT_CHANGE_CIPHER_SPEC
232                         || (negversion == TLS1_3_VERSION
233                             && msgtype == SSL3_MT_SERVER_HELLO)) {
234                     fragment = 0;
235                     break;
236                 }
237             }
238         }
239         /* Write any data we have left after fragmenting */
240         ret = 0;
241         if ((int)written < inl) {
242             ret = BIO_write(next, in + written, inl - written);
243         }
244 
245         if (ret <= 0 && BIO_should_write(next))
246             BIO_set_retry_write(bio);
247         else
248             ret += written;
249     } else {
250         ctrs->wctr++;
251         BIO_set_retry_write(bio);
252     }
253 
254     return ret;
255 }
256 
async_ctrl(BIO * bio,int cmd,long num,void * ptr)257 static long async_ctrl(BIO *bio, int cmd, long num, void *ptr)
258 {
259     long ret;
260     BIO *next = BIO_next(bio);
261 
262     if (next == NULL)
263         return 0;
264 
265     switch (cmd) {
266     case BIO_CTRL_DUP:
267         ret = 0L;
268         break;
269     default:
270         ret = BIO_ctrl(next, cmd, num, ptr);
271         break;
272     }
273     return ret;
274 }
275 
async_gets(BIO * bio,char * buf,int size)276 static int async_gets(BIO *bio, char *buf, int size)
277 {
278     /* We don't support this - not needed anyway */
279     return -1;
280 }
281 
async_puts(BIO * bio,const char * str)282 static int async_puts(BIO *bio, const char *str)
283 {
284     return async_write(bio, str, strlen(str));
285 }
286 
287 #define MAX_ATTEMPTS    100
288 
test_asyncio(int test)289 static int test_asyncio(int test)
290 {
291     SSL_CTX *serverctx = NULL, *clientctx = NULL;
292     SSL *serverssl = NULL, *clientssl = NULL;
293     BIO *s_to_c_fbio = NULL, *c_to_s_fbio = NULL;
294     int testresult = 0, ret;
295     size_t i, j;
296     const char testdata[] = "Test data";
297     char buf[sizeof(testdata)];
298 
299     if (!TEST_true(create_ssl_ctx_pair(TLS_server_method(), TLS_client_method(),
300                                        TLS1_VERSION, TLS_MAX_VERSION,
301                                        &serverctx, &clientctx, cert, privkey)))
302         goto end;
303 
304     /*
305      * We do 2 test runs. The first time around we just do a normal handshake
306      * with lots of async io going on. The second time around we also break up
307      * all records so that the content is only one byte length (up until the
308      * CCS)
309      */
310     if (test == 1)
311         fragment = 1;
312 
313 
314     s_to_c_fbio = BIO_new(bio_f_async_filter());
315     c_to_s_fbio = BIO_new(bio_f_async_filter());
316     if (!TEST_ptr(s_to_c_fbio)
317             || !TEST_ptr(c_to_s_fbio)) {
318         BIO_free(s_to_c_fbio);
319         BIO_free(c_to_s_fbio);
320         goto end;
321     }
322 
323     /* BIOs get freed on error */
324     if (!TEST_true(create_ssl_objects(serverctx, clientctx, &serverssl,
325                                       &clientssl, s_to_c_fbio, c_to_s_fbio))
326             || !TEST_true(create_ssl_connection(serverssl, clientssl,
327                           SSL_ERROR_NONE)))
328         goto end;
329 
330     /*
331      * Send and receive some test data. Do the whole thing twice to ensure
332      * we hit at least one async event in both reading and writing
333      */
334     for (j = 0; j < 2; j++) {
335         int len;
336 
337         /*
338          * Write some test data. It should never take more than 2 attempts
339          * (the first one might be a retryable fail).
340          */
341         for (ret = -1, i = 0, len = 0; len != sizeof(testdata) && i < 2;
342             i++) {
343             ret = SSL_write(clientssl, testdata + len,
344                 sizeof(testdata) - len);
345             if (ret > 0) {
346                 len += ret;
347             } else {
348                 int ssl_error = SSL_get_error(clientssl, ret);
349 
350                 if (!TEST_false(ssl_error == SSL_ERROR_SYSCALL ||
351                                 ssl_error == SSL_ERROR_SSL))
352                     goto end;
353             }
354         }
355         if (!TEST_size_t_eq(len, sizeof(testdata)))
356             goto end;
357 
358         /*
359          * Now read the test data. It may take more attempts here because
360          * it could fail once for each byte read, including all overhead
361          * bytes from the record header/padding etc.
362          */
363         for (ret = -1, i = 0, len = 0; len != sizeof(testdata) &&
364                 i < MAX_ATTEMPTS; i++) {
365             ret = SSL_read(serverssl, buf + len, sizeof(buf) - len);
366             if (ret > 0) {
367                 len += ret;
368             } else {
369                 int ssl_error = SSL_get_error(serverssl, ret);
370 
371                 if (!TEST_false(ssl_error == SSL_ERROR_SYSCALL ||
372                                 ssl_error == SSL_ERROR_SSL))
373                     goto end;
374             }
375         }
376         if (!TEST_mem_eq(testdata, sizeof(testdata), buf, len))
377             goto end;
378     }
379 
380     /* Also frees the BIOs */
381     SSL_free(clientssl);
382     SSL_free(serverssl);
383     clientssl = serverssl = NULL;
384 
385     testresult = 1;
386 
387  end:
388     SSL_free(clientssl);
389     SSL_free(serverssl);
390     SSL_CTX_free(clientctx);
391     SSL_CTX_free(serverctx);
392 
393     return testresult;
394 }
395 
setup_tests(void)396 int setup_tests(void)
397 {
398     if (!TEST_ptr(cert = test_get_argument(0))
399             || !TEST_ptr(privkey = test_get_argument(1)))
400         return 0;
401 
402     ADD_ALL_TESTS(test_asyncio, 2);
403     return 1;
404 }
405 
cleanup_tests(void)406 void cleanup_tests(void)
407 {
408     BIO_meth_free(methods_async);
409 }
410