yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2006-2021 The OpenSSL Project Authors. All Rights Reserved. |
| 3 | * |
| 4 | * Licensed under the OpenSSL license (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 | ASN1_STATE_HEADER, |
| 28 | ASN1_STATE_HEADER_COPY, |
| 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 | if (ctx->prefix_free != NULL) |
| 142 | ctx->prefix_free(b, &ctx->ex_buf, &ctx->ex_len, &ctx->ex_arg); |
| 143 | if (ctx->suffix_free != NULL) |
| 144 | ctx->suffix_free(b, &ctx->ex_buf, &ctx->ex_len, &ctx->ex_arg); |
| 145 | |
| 146 | OPENSSL_free(ctx->buf); |
| 147 | OPENSSL_free(ctx); |
| 148 | BIO_set_data(b, NULL); |
| 149 | BIO_set_init(b, 0); |
| 150 | |
| 151 | return 1; |
| 152 | } |
| 153 | |
| 154 | static int asn1_bio_write(BIO *b, const char *in, int inl) |
| 155 | { |
| 156 | BIO_ASN1_BUF_CTX *ctx; |
| 157 | int wrmax, wrlen, ret; |
| 158 | unsigned char *p; |
| 159 | BIO *next; |
| 160 | |
| 161 | ctx = BIO_get_data(b); |
| 162 | next = BIO_next(b); |
| 163 | if (in == NULL || inl < 0 || ctx == NULL || next == NULL) |
| 164 | return 0; |
| 165 | |
| 166 | wrlen = 0; |
| 167 | ret = -1; |
| 168 | |
| 169 | for (;;) { |
| 170 | switch (ctx->state) { |
| 171 | /* Setup prefix data, call it */ |
| 172 | case ASN1_STATE_START: |
| 173 | if (!asn1_bio_setup_ex(b, ctx, ctx->prefix, |
| 174 | ASN1_STATE_PRE_COPY, ASN1_STATE_HEADER)) |
| 175 | return 0; |
| 176 | break; |
| 177 | |
| 178 | /* Copy any pre data first */ |
| 179 | case ASN1_STATE_PRE_COPY: |
| 180 | |
| 181 | ret = asn1_bio_flush_ex(b, ctx, ctx->prefix_free, |
| 182 | ASN1_STATE_HEADER); |
| 183 | |
| 184 | if (ret <= 0) |
| 185 | goto done; |
| 186 | |
| 187 | break; |
| 188 | |
| 189 | case ASN1_STATE_HEADER: |
| 190 | ctx->buflen = ASN1_object_size(0, inl, ctx->asn1_tag) - inl; |
| 191 | if (!ossl_assert(ctx->buflen <= ctx->bufsize)) |
| 192 | return 0; |
| 193 | p = ctx->buf; |
| 194 | ASN1_put_object(&p, 0, inl, ctx->asn1_tag, ctx->asn1_class); |
| 195 | ctx->copylen = inl; |
| 196 | ctx->state = ASN1_STATE_HEADER_COPY; |
| 197 | |
| 198 | break; |
| 199 | |
| 200 | case ASN1_STATE_HEADER_COPY: |
| 201 | ret = BIO_write(next, ctx->buf + ctx->bufpos, ctx->buflen); |
| 202 | if (ret <= 0) |
| 203 | goto done; |
| 204 | |
| 205 | ctx->buflen -= ret; |
| 206 | if (ctx->buflen) |
| 207 | ctx->bufpos += ret; |
| 208 | else { |
| 209 | ctx->bufpos = 0; |
| 210 | ctx->state = ASN1_STATE_DATA_COPY; |
| 211 | } |
| 212 | |
| 213 | break; |
| 214 | |
| 215 | case ASN1_STATE_DATA_COPY: |
| 216 | |
| 217 | if (inl > ctx->copylen) |
| 218 | wrmax = ctx->copylen; |
| 219 | else |
| 220 | wrmax = inl; |
| 221 | ret = BIO_write(next, in, wrmax); |
| 222 | if (ret <= 0) |
| 223 | goto done; |
| 224 | wrlen += ret; |
| 225 | ctx->copylen -= ret; |
| 226 | in += ret; |
| 227 | inl -= ret; |
| 228 | |
| 229 | if (ctx->copylen == 0) |
| 230 | ctx->state = ASN1_STATE_HEADER; |
| 231 | |
| 232 | if (inl == 0) |
| 233 | goto done; |
| 234 | |
| 235 | break; |
| 236 | |
| 237 | case ASN1_STATE_POST_COPY: |
| 238 | case ASN1_STATE_DONE: |
| 239 | BIO_clear_retry_flags(b); |
| 240 | return 0; |
| 241 | |
| 242 | } |
| 243 | |
| 244 | } |
| 245 | |
| 246 | done: |
| 247 | BIO_clear_retry_flags(b); |
| 248 | BIO_copy_next_retry(b); |
| 249 | |
| 250 | return (wrlen > 0) ? wrlen : ret; |
| 251 | |
| 252 | } |
| 253 | |
| 254 | static int asn1_bio_flush_ex(BIO *b, BIO_ASN1_BUF_CTX *ctx, |
| 255 | asn1_ps_func *cleanup, asn1_bio_state_t next) |
| 256 | { |
| 257 | int ret; |
| 258 | |
| 259 | if (ctx->ex_len <= 0) |
| 260 | return 1; |
| 261 | for (;;) { |
| 262 | ret = BIO_write(BIO_next(b), ctx->ex_buf + ctx->ex_pos, ctx->ex_len); |
| 263 | if (ret <= 0) |
| 264 | break; |
| 265 | ctx->ex_len -= ret; |
| 266 | if (ctx->ex_len > 0) |
| 267 | ctx->ex_pos += ret; |
| 268 | else { |
| 269 | if (cleanup) |
| 270 | cleanup(b, &ctx->ex_buf, &ctx->ex_len, &ctx->ex_arg); |
| 271 | ctx->state = next; |
| 272 | ctx->ex_pos = 0; |
| 273 | break; |
| 274 | } |
| 275 | } |
| 276 | return ret; |
| 277 | } |
| 278 | |
| 279 | static int asn1_bio_setup_ex(BIO *b, BIO_ASN1_BUF_CTX *ctx, |
| 280 | asn1_ps_func *setup, |
| 281 | asn1_bio_state_t ex_state, |
| 282 | asn1_bio_state_t other_state) |
| 283 | { |
| 284 | if (setup && !setup(b, &ctx->ex_buf, &ctx->ex_len, &ctx->ex_arg)) { |
| 285 | BIO_clear_retry_flags(b); |
| 286 | return 0; |
| 287 | } |
| 288 | if (ctx->ex_len > 0) |
| 289 | ctx->state = ex_state; |
| 290 | else |
| 291 | ctx->state = other_state; |
| 292 | return 1; |
| 293 | } |
| 294 | |
| 295 | static int asn1_bio_read(BIO *b, char *in, int inl) |
| 296 | { |
| 297 | BIO *next = BIO_next(b); |
| 298 | if (next == NULL) |
| 299 | return 0; |
| 300 | return BIO_read(next, in, inl); |
| 301 | } |
| 302 | |
| 303 | static int asn1_bio_puts(BIO *b, const char *str) |
| 304 | { |
| 305 | return asn1_bio_write(b, str, strlen(str)); |
| 306 | } |
| 307 | |
| 308 | static int asn1_bio_gets(BIO *b, char *str, int size) |
| 309 | { |
| 310 | BIO *next = BIO_next(b); |
| 311 | if (next == NULL) |
| 312 | return 0; |
| 313 | return BIO_gets(next, str, size); |
| 314 | } |
| 315 | |
| 316 | static long asn1_bio_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp) |
| 317 | { |
| 318 | BIO *next = BIO_next(b); |
| 319 | if (next == NULL) |
| 320 | return 0; |
| 321 | return BIO_callback_ctrl(next, cmd, fp); |
| 322 | } |
| 323 | |
| 324 | static long asn1_bio_ctrl(BIO *b, int cmd, long arg1, void *arg2) |
| 325 | { |
| 326 | BIO_ASN1_BUF_CTX *ctx; |
| 327 | BIO_ASN1_EX_FUNCS *ex_func; |
| 328 | long ret = 1; |
| 329 | BIO *next; |
| 330 | |
| 331 | ctx = BIO_get_data(b); |
| 332 | if (ctx == NULL) |
| 333 | return 0; |
| 334 | next = BIO_next(b); |
| 335 | switch (cmd) { |
| 336 | |
| 337 | case BIO_C_SET_PREFIX: |
| 338 | ex_func = arg2; |
| 339 | ctx->prefix = ex_func->ex_func; |
| 340 | ctx->prefix_free = ex_func->ex_free_func; |
| 341 | break; |
| 342 | |
| 343 | case BIO_C_GET_PREFIX: |
| 344 | ex_func = arg2; |
| 345 | ex_func->ex_func = ctx->prefix; |
| 346 | ex_func->ex_free_func = ctx->prefix_free; |
| 347 | break; |
| 348 | |
| 349 | case BIO_C_SET_SUFFIX: |
| 350 | ex_func = arg2; |
| 351 | ctx->suffix = ex_func->ex_func; |
| 352 | ctx->suffix_free = ex_func->ex_free_func; |
| 353 | break; |
| 354 | |
| 355 | case BIO_C_GET_SUFFIX: |
| 356 | ex_func = arg2; |
| 357 | ex_func->ex_func = ctx->suffix; |
| 358 | ex_func->ex_free_func = ctx->suffix_free; |
| 359 | break; |
| 360 | |
| 361 | case BIO_C_SET_EX_ARG: |
| 362 | ctx->ex_arg = arg2; |
| 363 | break; |
| 364 | |
| 365 | case BIO_C_GET_EX_ARG: |
| 366 | *(void **)arg2 = ctx->ex_arg; |
| 367 | break; |
| 368 | |
| 369 | case BIO_CTRL_FLUSH: |
| 370 | if (next == NULL) |
| 371 | return 0; |
| 372 | |
| 373 | /* Call post function if possible */ |
| 374 | if (ctx->state == ASN1_STATE_HEADER) { |
| 375 | if (!asn1_bio_setup_ex(b, ctx, ctx->suffix, |
| 376 | ASN1_STATE_POST_COPY, ASN1_STATE_DONE)) |
| 377 | return 0; |
| 378 | } |
| 379 | |
| 380 | if (ctx->state == ASN1_STATE_POST_COPY) { |
| 381 | ret = asn1_bio_flush_ex(b, ctx, ctx->suffix_free, |
| 382 | ASN1_STATE_DONE); |
| 383 | if (ret <= 0) |
| 384 | return ret; |
| 385 | } |
| 386 | |
| 387 | if (ctx->state == ASN1_STATE_DONE) |
| 388 | return BIO_ctrl(next, cmd, arg1, arg2); |
| 389 | else { |
| 390 | BIO_clear_retry_flags(b); |
| 391 | return 0; |
| 392 | } |
| 393 | |
| 394 | default: |
| 395 | if (next == NULL) |
| 396 | return 0; |
| 397 | return BIO_ctrl(next, cmd, arg1, arg2); |
| 398 | |
| 399 | } |
| 400 | |
| 401 | return ret; |
| 402 | } |
| 403 | |
| 404 | static int asn1_bio_set_ex(BIO *b, int cmd, |
| 405 | asn1_ps_func *ex_func, asn1_ps_func *ex_free_func) |
| 406 | { |
| 407 | BIO_ASN1_EX_FUNCS extmp; |
| 408 | extmp.ex_func = ex_func; |
| 409 | extmp.ex_free_func = ex_free_func; |
| 410 | return BIO_ctrl(b, cmd, 0, &extmp); |
| 411 | } |
| 412 | |
| 413 | static int asn1_bio_get_ex(BIO *b, int cmd, |
| 414 | asn1_ps_func **ex_func, |
| 415 | asn1_ps_func **ex_free_func) |
| 416 | { |
| 417 | BIO_ASN1_EX_FUNCS extmp; |
| 418 | int ret; |
| 419 | ret = BIO_ctrl(b, cmd, 0, &extmp); |
| 420 | if (ret > 0) { |
| 421 | *ex_func = extmp.ex_func; |
| 422 | *ex_free_func = extmp.ex_free_func; |
| 423 | } |
| 424 | return ret; |
| 425 | } |
| 426 | |
| 427 | int BIO_asn1_set_prefix(BIO *b, asn1_ps_func *prefix, |
| 428 | asn1_ps_func *prefix_free) |
| 429 | { |
| 430 | return asn1_bio_set_ex(b, BIO_C_SET_PREFIX, prefix, prefix_free); |
| 431 | } |
| 432 | |
| 433 | int BIO_asn1_get_prefix(BIO *b, asn1_ps_func **pprefix, |
| 434 | asn1_ps_func **pprefix_free) |
| 435 | { |
| 436 | return asn1_bio_get_ex(b, BIO_C_GET_PREFIX, pprefix, pprefix_free); |
| 437 | } |
| 438 | |
| 439 | int BIO_asn1_set_suffix(BIO *b, asn1_ps_func *suffix, |
| 440 | asn1_ps_func *suffix_free) |
| 441 | { |
| 442 | return asn1_bio_set_ex(b, BIO_C_SET_SUFFIX, suffix, suffix_free); |
| 443 | } |
| 444 | |
| 445 | int BIO_asn1_get_suffix(BIO *b, asn1_ps_func **psuffix, |
| 446 | asn1_ps_func **psuffix_free) |
| 447 | { |
| 448 | return asn1_bio_get_ex(b, BIO_C_GET_SUFFIX, psuffix, psuffix_free); |
| 449 | } |