1 | /* |
2 | * Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
5 | * this file except in compliance with the License. You can obtain a copy |
6 | * in the file LICENSE in the source distribution or at |
7 | * https://www.openssl.org/source/license.html |
8 | */ |
9 | |
10 | /* |
11 | * Experimental ASN1 BIO. When written through the data is converted to an |
12 | * ASN1 string type: default is OCTET STRING. Additional functions can be |
13 | * provided to add prefix and suffix data. |
14 | */ |
15 | |
16 | #include <string.h> |
17 | #include "internal/bio.h" |
18 | #include <openssl/asn1.h> |
19 | #include "internal/cryptlib.h" |
20 | |
21 | /* Must be large enough for biggest tag+length */ |
22 | #define DEFAULT_ASN1_BUF_SIZE 20 |
23 | |
24 | typedef enum { |
25 | ASN1_STATE_START, |
26 | ASN1_STATE_PRE_COPY, |
27 | , |
28 | , |
29 | ASN1_STATE_DATA_COPY, |
30 | ASN1_STATE_POST_COPY, |
31 | ASN1_STATE_DONE |
32 | } asn1_bio_state_t; |
33 | |
34 | typedef struct BIO_ASN1_EX_FUNCS_st { |
35 | asn1_ps_func *ex_func; |
36 | asn1_ps_func *ex_free_func; |
37 | } BIO_ASN1_EX_FUNCS; |
38 | |
39 | typedef struct BIO_ASN1_BUF_CTX_t { |
40 | /* Internal state */ |
41 | asn1_bio_state_t state; |
42 | /* Internal buffer */ |
43 | unsigned char *buf; |
44 | /* Size of buffer */ |
45 | int bufsize; |
46 | /* Current position in buffer */ |
47 | int bufpos; |
48 | /* Current buffer length */ |
49 | int buflen; |
50 | /* Amount of data to copy */ |
51 | int copylen; |
52 | /* Class and tag to use */ |
53 | int asn1_class, asn1_tag; |
54 | asn1_ps_func *prefix, *prefix_free, *suffix, *suffix_free; |
55 | /* Extra buffer for prefix and suffix data */ |
56 | unsigned char *ex_buf; |
57 | int ex_len; |
58 | int ex_pos; |
59 | void *ex_arg; |
60 | } BIO_ASN1_BUF_CTX; |
61 | |
62 | static int asn1_bio_write(BIO *h, const char *buf, int num); |
63 | static int asn1_bio_read(BIO *h, char *buf, int size); |
64 | static int asn1_bio_puts(BIO *h, const char *str); |
65 | static int asn1_bio_gets(BIO *h, char *str, int size); |
66 | static long asn1_bio_ctrl(BIO *h, int cmd, long arg1, void *arg2); |
67 | static int asn1_bio_new(BIO *h); |
68 | static int asn1_bio_free(BIO *data); |
69 | static long asn1_bio_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp); |
70 | |
71 | static int asn1_bio_init(BIO_ASN1_BUF_CTX *ctx, int size); |
72 | static int asn1_bio_flush_ex(BIO *b, BIO_ASN1_BUF_CTX *ctx, |
73 | asn1_ps_func *cleanup, asn1_bio_state_t next); |
74 | static int asn1_bio_setup_ex(BIO *b, BIO_ASN1_BUF_CTX *ctx, |
75 | asn1_ps_func *setup, |
76 | asn1_bio_state_t ex_state, |
77 | asn1_bio_state_t other_state); |
78 | |
79 | static const BIO_METHOD methods_asn1 = { |
80 | BIO_TYPE_ASN1, |
81 | "asn1" , |
82 | /* TODO: Convert to new style write function */ |
83 | bwrite_conv, |
84 | asn1_bio_write, |
85 | /* TODO: Convert to new style read function */ |
86 | bread_conv, |
87 | asn1_bio_read, |
88 | asn1_bio_puts, |
89 | asn1_bio_gets, |
90 | asn1_bio_ctrl, |
91 | asn1_bio_new, |
92 | asn1_bio_free, |
93 | asn1_bio_callback_ctrl, |
94 | }; |
95 | |
96 | const BIO_METHOD *BIO_f_asn1(void) |
97 | { |
98 | return &methods_asn1; |
99 | } |
100 | |
101 | static int asn1_bio_new(BIO *b) |
102 | { |
103 | BIO_ASN1_BUF_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx)); |
104 | |
105 | if (ctx == NULL) |
106 | return 0; |
107 | if (!asn1_bio_init(ctx, DEFAULT_ASN1_BUF_SIZE)) { |
108 | OPENSSL_free(ctx); |
109 | return 0; |
110 | } |
111 | BIO_set_data(b, ctx); |
112 | BIO_set_init(b, 1); |
113 | |
114 | return 1; |
115 | } |
116 | |
117 | static int asn1_bio_init(BIO_ASN1_BUF_CTX *ctx, int size) |
118 | { |
119 | if ((ctx->buf = OPENSSL_malloc(size)) == NULL) { |
120 | ASN1err(ASN1_F_ASN1_BIO_INIT, ERR_R_MALLOC_FAILURE); |
121 | return 0; |
122 | } |
123 | ctx->bufsize = size; |
124 | ctx->asn1_class = V_ASN1_UNIVERSAL; |
125 | ctx->asn1_tag = V_ASN1_OCTET_STRING; |
126 | ctx->state = ASN1_STATE_START; |
127 | return 1; |
128 | } |
129 | |
130 | static int asn1_bio_free(BIO *b) |
131 | { |
132 | BIO_ASN1_BUF_CTX *ctx; |
133 | |
134 | if (b == NULL) |
135 | return 0; |
136 | |
137 | ctx = BIO_get_data(b); |
138 | if (ctx == NULL) |
139 | return 0; |
140 | |
141 | OPENSSL_free(ctx->buf); |
142 | OPENSSL_free(ctx); |
143 | BIO_set_data(b, NULL); |
144 | BIO_set_init(b, 0); |
145 | |
146 | return 1; |
147 | } |
148 | |
149 | static int asn1_bio_write(BIO *b, const char *in, int inl) |
150 | { |
151 | BIO_ASN1_BUF_CTX *ctx; |
152 | int wrmax, wrlen, ret; |
153 | unsigned char *p; |
154 | BIO *next; |
155 | |
156 | ctx = BIO_get_data(b); |
157 | next = BIO_next(b); |
158 | if (in == NULL || inl < 0 || ctx == NULL || next == NULL) |
159 | return 0; |
160 | |
161 | wrlen = 0; |
162 | ret = -1; |
163 | |
164 | for (;;) { |
165 | switch (ctx->state) { |
166 | /* Setup prefix data, call it */ |
167 | case ASN1_STATE_START: |
168 | if (!asn1_bio_setup_ex(b, ctx, ctx->prefix, |
169 | ASN1_STATE_PRE_COPY, ASN1_STATE_HEADER)) |
170 | return 0; |
171 | break; |
172 | |
173 | /* Copy any pre data first */ |
174 | case ASN1_STATE_PRE_COPY: |
175 | |
176 | ret = asn1_bio_flush_ex(b, ctx, ctx->prefix_free, |
177 | ASN1_STATE_HEADER); |
178 | |
179 | if (ret <= 0) |
180 | goto done; |
181 | |
182 | break; |
183 | |
184 | case ASN1_STATE_HEADER: |
185 | ctx->buflen = ASN1_object_size(0, inl, ctx->asn1_tag) - inl; |
186 | if (!ossl_assert(ctx->buflen <= ctx->bufsize)) |
187 | return 0; |
188 | p = ctx->buf; |
189 | ASN1_put_object(&p, 0, inl, ctx->asn1_tag, ctx->asn1_class); |
190 | ctx->copylen = inl; |
191 | ctx->state = ASN1_STATE_HEADER_COPY; |
192 | |
193 | break; |
194 | |
195 | case ASN1_STATE_HEADER_COPY: |
196 | ret = BIO_write(next, ctx->buf + ctx->bufpos, ctx->buflen); |
197 | if (ret <= 0) |
198 | goto done; |
199 | |
200 | ctx->buflen -= ret; |
201 | if (ctx->buflen) |
202 | ctx->bufpos += ret; |
203 | else { |
204 | ctx->bufpos = 0; |
205 | ctx->state = ASN1_STATE_DATA_COPY; |
206 | } |
207 | |
208 | break; |
209 | |
210 | case ASN1_STATE_DATA_COPY: |
211 | |
212 | if (inl > ctx->copylen) |
213 | wrmax = ctx->copylen; |
214 | else |
215 | wrmax = inl; |
216 | ret = BIO_write(next, in, wrmax); |
217 | if (ret <= 0) |
218 | goto done; |
219 | wrlen += ret; |
220 | ctx->copylen -= ret; |
221 | in += ret; |
222 | inl -= ret; |
223 | |
224 | if (ctx->copylen == 0) |
225 | ctx->state = ASN1_STATE_HEADER; |
226 | |
227 | if (inl == 0) |
228 | goto done; |
229 | |
230 | break; |
231 | |
232 | case ASN1_STATE_POST_COPY: |
233 | case ASN1_STATE_DONE: |
234 | BIO_clear_retry_flags(b); |
235 | return 0; |
236 | |
237 | } |
238 | |
239 | } |
240 | |
241 | done: |
242 | BIO_clear_retry_flags(b); |
243 | BIO_copy_next_retry(b); |
244 | |
245 | return (wrlen > 0) ? wrlen : ret; |
246 | |
247 | } |
248 | |
249 | static int asn1_bio_flush_ex(BIO *b, BIO_ASN1_BUF_CTX *ctx, |
250 | asn1_ps_func *cleanup, asn1_bio_state_t next) |
251 | { |
252 | int ret; |
253 | |
254 | if (ctx->ex_len <= 0) |
255 | return 1; |
256 | for (;;) { |
257 | ret = BIO_write(BIO_next(b), ctx->ex_buf + ctx->ex_pos, ctx->ex_len); |
258 | if (ret <= 0) |
259 | break; |
260 | ctx->ex_len -= ret; |
261 | if (ctx->ex_len > 0) |
262 | ctx->ex_pos += ret; |
263 | else { |
264 | if (cleanup) |
265 | cleanup(b, &ctx->ex_buf, &ctx->ex_len, &ctx->ex_arg); |
266 | ctx->state = next; |
267 | ctx->ex_pos = 0; |
268 | break; |
269 | } |
270 | } |
271 | return ret; |
272 | } |
273 | |
274 | static int asn1_bio_setup_ex(BIO *b, BIO_ASN1_BUF_CTX *ctx, |
275 | asn1_ps_func *setup, |
276 | asn1_bio_state_t ex_state, |
277 | asn1_bio_state_t other_state) |
278 | { |
279 | if (setup && !setup(b, &ctx->ex_buf, &ctx->ex_len, &ctx->ex_arg)) { |
280 | BIO_clear_retry_flags(b); |
281 | return 0; |
282 | } |
283 | if (ctx->ex_len > 0) |
284 | ctx->state = ex_state; |
285 | else |
286 | ctx->state = other_state; |
287 | return 1; |
288 | } |
289 | |
290 | static int asn1_bio_read(BIO *b, char *in, int inl) |
291 | { |
292 | BIO *next = BIO_next(b); |
293 | if (next == NULL) |
294 | return 0; |
295 | return BIO_read(next, in, inl); |
296 | } |
297 | |
298 | static int asn1_bio_puts(BIO *b, const char *str) |
299 | { |
300 | return asn1_bio_write(b, str, strlen(str)); |
301 | } |
302 | |
303 | static int asn1_bio_gets(BIO *b, char *str, int size) |
304 | { |
305 | BIO *next = BIO_next(b); |
306 | if (next == NULL) |
307 | return 0; |
308 | return BIO_gets(next, str, size); |
309 | } |
310 | |
311 | static long asn1_bio_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp) |
312 | { |
313 | BIO *next = BIO_next(b); |
314 | if (next == NULL) |
315 | return 0; |
316 | return BIO_callback_ctrl(next, cmd, fp); |
317 | } |
318 | |
319 | static long asn1_bio_ctrl(BIO *b, int cmd, long arg1, void *arg2) |
320 | { |
321 | BIO_ASN1_BUF_CTX *ctx; |
322 | BIO_ASN1_EX_FUNCS *ex_func; |
323 | long ret = 1; |
324 | BIO *next; |
325 | |
326 | ctx = BIO_get_data(b); |
327 | if (ctx == NULL) |
328 | return 0; |
329 | next = BIO_next(b); |
330 | switch (cmd) { |
331 | |
332 | case BIO_C_SET_PREFIX: |
333 | ex_func = arg2; |
334 | ctx->prefix = ex_func->ex_func; |
335 | ctx->prefix_free = ex_func->ex_free_func; |
336 | break; |
337 | |
338 | case BIO_C_GET_PREFIX: |
339 | ex_func = arg2; |
340 | ex_func->ex_func = ctx->prefix; |
341 | ex_func->ex_free_func = ctx->prefix_free; |
342 | break; |
343 | |
344 | case BIO_C_SET_SUFFIX: |
345 | ex_func = arg2; |
346 | ctx->suffix = ex_func->ex_func; |
347 | ctx->suffix_free = ex_func->ex_free_func; |
348 | break; |
349 | |
350 | case BIO_C_GET_SUFFIX: |
351 | ex_func = arg2; |
352 | ex_func->ex_func = ctx->suffix; |
353 | ex_func->ex_free_func = ctx->suffix_free; |
354 | break; |
355 | |
356 | case BIO_C_SET_EX_ARG: |
357 | ctx->ex_arg = arg2; |
358 | break; |
359 | |
360 | case BIO_C_GET_EX_ARG: |
361 | *(void **)arg2 = ctx->ex_arg; |
362 | break; |
363 | |
364 | case BIO_CTRL_FLUSH: |
365 | if (next == NULL) |
366 | return 0; |
367 | |
368 | /* Call post function if possible */ |
369 | if (ctx->state == ASN1_STATE_HEADER) { |
370 | if (!asn1_bio_setup_ex(b, ctx, ctx->suffix, |
371 | ASN1_STATE_POST_COPY, ASN1_STATE_DONE)) |
372 | return 0; |
373 | } |
374 | |
375 | if (ctx->state == ASN1_STATE_POST_COPY) { |
376 | ret = asn1_bio_flush_ex(b, ctx, ctx->suffix_free, |
377 | ASN1_STATE_DONE); |
378 | if (ret <= 0) |
379 | return ret; |
380 | } |
381 | |
382 | if (ctx->state == ASN1_STATE_DONE) |
383 | return BIO_ctrl(next, cmd, arg1, arg2); |
384 | else { |
385 | BIO_clear_retry_flags(b); |
386 | return 0; |
387 | } |
388 | |
389 | default: |
390 | if (next == NULL) |
391 | return 0; |
392 | return BIO_ctrl(next, cmd, arg1, arg2); |
393 | |
394 | } |
395 | |
396 | return ret; |
397 | } |
398 | |
399 | static int asn1_bio_set_ex(BIO *b, int cmd, |
400 | asn1_ps_func *ex_func, asn1_ps_func *ex_free_func) |
401 | { |
402 | BIO_ASN1_EX_FUNCS extmp; |
403 | extmp.ex_func = ex_func; |
404 | extmp.ex_free_func = ex_free_func; |
405 | return BIO_ctrl(b, cmd, 0, &extmp); |
406 | } |
407 | |
408 | static int asn1_bio_get_ex(BIO *b, int cmd, |
409 | asn1_ps_func **ex_func, |
410 | asn1_ps_func **ex_free_func) |
411 | { |
412 | BIO_ASN1_EX_FUNCS extmp; |
413 | int ret; |
414 | ret = BIO_ctrl(b, cmd, 0, &extmp); |
415 | if (ret > 0) { |
416 | *ex_func = extmp.ex_func; |
417 | *ex_free_func = extmp.ex_free_func; |
418 | } |
419 | return ret; |
420 | } |
421 | |
422 | int BIO_asn1_set_prefix(BIO *b, asn1_ps_func *prefix, |
423 | asn1_ps_func *prefix_free) |
424 | { |
425 | return asn1_bio_set_ex(b, BIO_C_SET_PREFIX, prefix, prefix_free); |
426 | } |
427 | |
428 | int BIO_asn1_get_prefix(BIO *b, asn1_ps_func **pprefix, |
429 | asn1_ps_func **pprefix_free) |
430 | { |
431 | return asn1_bio_get_ex(b, BIO_C_GET_PREFIX, pprefix, pprefix_free); |
432 | } |
433 | |
434 | int BIO_asn1_set_suffix(BIO *b, asn1_ps_func *suffix, |
435 | asn1_ps_func *suffix_free) |
436 | { |
437 | return asn1_bio_set_ex(b, BIO_C_SET_SUFFIX, suffix, suffix_free); |
438 | } |
439 | |
440 | int BIO_asn1_get_suffix(BIO *b, asn1_ps_func **psuffix, |
441 | asn1_ps_func **psuffix_free) |
442 | { |
443 | return asn1_bio_get_ex(b, BIO_C_GET_SUFFIX, psuffix, psuffix_free); |
444 | } |
445 | |