1 /* 2 * Copyright 1995-2018 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 #include <stdio.h> 11 #include <errno.h> 12 #include "bio_lcl.h" 13 #include "internal/cryptlib.h" 14 15 static int mem_write(BIO *h, const char *buf, int num); 16 static int mem_read(BIO *h, char *buf, int size); 17 static int mem_puts(BIO *h, const char *str); 18 static int mem_gets(BIO *h, char *str, int size); 19 static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2); 20 static int mem_new(BIO *h); 21 static int secmem_new(BIO *h); 22 static int mem_free(BIO *data); 23 static int mem_buf_free(BIO *data, int free_all); 24 static int mem_buf_sync(BIO *h); 25 26 static const BIO_METHOD mem_method = { 27 BIO_TYPE_MEM, 28 "memory buffer", 29 /* TODO: Convert to new style write function */ 30 bwrite_conv, 31 mem_write, 32 /* TODO: Convert to new style read function */ 33 bread_conv, 34 mem_read, 35 mem_puts, 36 mem_gets, 37 mem_ctrl, 38 mem_new, 39 mem_free, 40 NULL, /* mem_callback_ctrl */ 41 }; 42 43 static const BIO_METHOD secmem_method = { 44 BIO_TYPE_MEM, 45 "secure memory buffer", 46 /* TODO: Convert to new style write function */ 47 bwrite_conv, 48 mem_write, 49 /* TODO: Convert to new style read function */ 50 bread_conv, 51 mem_read, 52 mem_puts, 53 mem_gets, 54 mem_ctrl, 55 secmem_new, 56 mem_free, 57 NULL, /* mem_callback_ctrl */ 58 }; 59 60 /* BIO memory stores buffer and read pointer */ 61 typedef struct bio_buf_mem_st { 62 struct buf_mem_st *buf; /* allocated buffer */ 63 struct buf_mem_st *readp; /* read pointer */ 64 } BIO_BUF_MEM; 65 66 /* 67 * bio->num is used to hold the value to return on 'empty', if it is 0, 68 * should_retry is not set 69 */ 70 71 const BIO_METHOD *BIO_s_mem(void) 72 { 73 return &mem_method; 74 } 75 76 const BIO_METHOD *BIO_s_secmem(void) 77 { 78 return(&secmem_method); 79 } 80 81 BIO *BIO_new_mem_buf(const void *buf, int len) 82 { 83 BIO *ret; 84 BUF_MEM *b; 85 BIO_BUF_MEM *bb; 86 size_t sz; 87 88 if (buf == NULL) { 89 BIOerr(BIO_F_BIO_NEW_MEM_BUF, BIO_R_NULL_PARAMETER); 90 return NULL; 91 } 92 sz = (len < 0) ? strlen(buf) : (size_t)len; 93 if ((ret = BIO_new(BIO_s_mem())) == NULL) 94 return NULL; 95 bb = (BIO_BUF_MEM *)ret->ptr; 96 b = bb->buf; 97 /* Cast away const and trust in the MEM_RDONLY flag. */ 98 b->data = (void *)buf; 99 b->length = sz; 100 b->max = sz; 101 *bb->readp = *bb->buf; 102 ret->flags |= BIO_FLAGS_MEM_RDONLY; 103 /* Since this is static data retrying won't help */ 104 ret->num = 0; 105 return ret; 106 } 107 108 static int mem_init(BIO *bi, unsigned long flags) 109 { 110 BIO_BUF_MEM *bb = OPENSSL_zalloc(sizeof(*bb)); 111 112 if (bb == NULL) 113 return 0; 114 if ((bb->buf = BUF_MEM_new_ex(flags)) == NULL) { 115 OPENSSL_free(bb); 116 return 0; 117 } 118 if ((bb->readp = OPENSSL_zalloc(sizeof(*bb->readp))) == NULL) { 119 BUF_MEM_free(bb->buf); 120 OPENSSL_free(bb); 121 return 0; 122 } 123 *bb->readp = *bb->buf; 124 bi->shutdown = 1; 125 bi->init = 1; 126 bi->num = -1; 127 bi->ptr = (char *)bb; 128 return 1; 129 } 130 131 static int mem_new(BIO *bi) 132 { 133 return mem_init(bi, 0L); 134 } 135 136 static int secmem_new(BIO *bi) 137 { 138 return mem_init(bi, BUF_MEM_FLAG_SECURE); 139 } 140 141 static int mem_free(BIO *a) 142 { 143 return mem_buf_free(a, 1); 144 } 145 146 static int mem_buf_free(BIO *a, int free_all) 147 { 148 if (a == NULL) 149 return 0; 150 151 if (a->shutdown && a->init && a->ptr != NULL) { 152 BIO_BUF_MEM *bb = (BIO_BUF_MEM *)a->ptr; 153 BUF_MEM *b = bb->buf; 154 155 if (a->flags & BIO_FLAGS_MEM_RDONLY) 156 b->data = NULL; 157 BUF_MEM_free(b); 158 if (free_all) { 159 OPENSSL_free(bb->readp); 160 OPENSSL_free(bb); 161 } 162 a->ptr = NULL; 163 } 164 return 1; 165 } 166 167 /* 168 * Reallocate memory buffer if read pointer differs 169 */ 170 static int mem_buf_sync(BIO *b) 171 { 172 if (b != NULL && b->init != 0 && b->ptr != NULL) { 173 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr; 174 175 if (bbm->readp->data != bbm->buf->data) { 176 memmove(bbm->buf->data, bbm->readp->data, bbm->readp->length); 177 bbm->buf->length = bbm->readp->length; 178 bbm->readp->data = bbm->buf->data; 179 } 180 } 181 return 0; 182 } 183 184 static int mem_read(BIO *b, char *out, int outl) 185 { 186 int ret = -1; 187 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr; 188 BUF_MEM *bm = bbm->readp; 189 190 BIO_clear_retry_flags(b); 191 ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl; 192 if ((out != NULL) && (ret > 0)) { 193 memcpy(out, bm->data, ret); 194 bm->length -= ret; 195 bm->data += ret; 196 } else if (bm->length == 0) { 197 ret = b->num; 198 if (ret != 0) 199 BIO_set_retry_read(b); 200 } 201 return ret; 202 } 203 204 static int mem_write(BIO *b, const char *in, int inl) 205 { 206 int ret = -1; 207 int blen; 208 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr; 209 210 if (in == NULL) { 211 BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER); 212 goto end; 213 } 214 if (b->flags & BIO_FLAGS_MEM_RDONLY) { 215 BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO); 216 goto end; 217 } 218 BIO_clear_retry_flags(b); 219 if (inl == 0) 220 return 0; 221 blen = bbm->readp->length; 222 mem_buf_sync(b); 223 if (BUF_MEM_grow_clean(bbm->buf, blen + inl) == 0) 224 goto end; 225 memcpy(bbm->buf->data + blen, in, inl); 226 *bbm->readp = *bbm->buf; 227 ret = inl; 228 end: 229 return ret; 230 } 231 232 static long mem_ctrl(BIO *b, int cmd, long num, void *ptr) 233 { 234 long ret = 1; 235 char **pptr; 236 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr; 237 BUF_MEM *bm; 238 239 switch (cmd) { 240 case BIO_CTRL_RESET: 241 bm = bbm->buf; 242 if (bm->data != NULL) { 243 /* For read only case reset to the start again */ 244 if ((b->flags & BIO_FLAGS_MEM_RDONLY) || (b->flags & BIO_FLAGS_NONCLEAR_RST)) { 245 bm->length = bm->max; 246 } else { 247 memset(bm->data, 0, bm->max); 248 bm->length = 0; 249 } 250 *bbm->readp = *bbm->buf; 251 } 252 break; 253 case BIO_CTRL_EOF: 254 bm = bbm->readp; 255 ret = (long)(bm->length == 0); 256 break; 257 case BIO_C_SET_BUF_MEM_EOF_RETURN: 258 b->num = (int)num; 259 break; 260 case BIO_CTRL_INFO: 261 bm = bbm->readp; 262 ret = (long)bm->length; 263 if (ptr != NULL) { 264 pptr = (char **)ptr; 265 *pptr = (char *)&(bm->data[0]); 266 } 267 break; 268 case BIO_C_SET_BUF_MEM: 269 mem_buf_free(b, 0); 270 b->shutdown = (int)num; 271 bbm->buf = ptr; 272 *bbm->readp = *bbm->buf; 273 b->ptr = bbm; 274 break; 275 case BIO_C_GET_BUF_MEM_PTR: 276 if (ptr != NULL) { 277 mem_buf_sync(b); 278 bm = bbm->readp; 279 pptr = (char **)ptr; 280 *pptr = (char *)bm; 281 } 282 break; 283 case BIO_CTRL_GET_CLOSE: 284 ret = (long)b->shutdown; 285 break; 286 case BIO_CTRL_SET_CLOSE: 287 b->shutdown = (int)num; 288 break; 289 case BIO_CTRL_WPENDING: 290 ret = 0L; 291 break; 292 case BIO_CTRL_PENDING: 293 bm = bbm->readp; 294 ret = (long)bm->length; 295 break; 296 case BIO_CTRL_DUP: 297 case BIO_CTRL_FLUSH: 298 ret = 1; 299 break; 300 case BIO_CTRL_PUSH: 301 case BIO_CTRL_POP: 302 default: 303 ret = 0; 304 break; 305 } 306 return ret; 307 } 308 309 static int mem_gets(BIO *bp, char *buf, int size) 310 { 311 int i, j; 312 int ret = -1; 313 char *p; 314 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)bp->ptr; 315 BUF_MEM *bm = bbm->readp; 316 317 BIO_clear_retry_flags(bp); 318 j = bm->length; 319 if ((size - 1) < j) 320 j = size - 1; 321 if (j <= 0) { 322 *buf = '\0'; 323 return 0; 324 } 325 p = bm->data; 326 for (i = 0; i < j; i++) { 327 if (p[i] == '\n') { 328 i++; 329 break; 330 } 331 } 332 333 /* 334 * i is now the max num of bytes to copy, either j or up to 335 * and including the first newline 336 */ 337 338 i = mem_read(bp, buf, i); 339 if (i > 0) 340 buf[i] = '\0'; 341 ret = i; 342 return ret; 343 } 344 345 static int mem_puts(BIO *bp, const char *str) 346 { 347 int n, ret; 348 349 n = strlen(str); 350 ret = mem_write(bp, str, n); 351 /* memory semantics is that it will always work */ 352 return ret; 353 } 354