1 /* $OpenBSD: buffer.c,v 1.26 2017/04/09 15:06:20 jsing Exp $ */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 63 #include <openssl/buffer.h> 64 #include <openssl/err.h> 65 66 /* 67 * LIMIT_BEFORE_EXPANSION is the maximum n such that (n + 3) / 3 * 4 < 2**31. 68 * That function is applied in several functions in this file and this limit 69 * ensures that the result fits in an int. 70 */ 71 #define LIMIT_BEFORE_EXPANSION 0x5ffffffc 72 73 BUF_MEM * 74 BUF_MEM_new(void) 75 { 76 BUF_MEM *ret; 77 78 if ((ret = calloc(1, sizeof(BUF_MEM))) == NULL) { 79 BUFerror(ERR_R_MALLOC_FAILURE); 80 return (NULL); 81 } 82 83 return (ret); 84 } 85 86 void 87 BUF_MEM_free(BUF_MEM *a) 88 { 89 if (a == NULL) 90 return; 91 92 if (a->data != NULL) { 93 explicit_bzero(a->data, a->max); 94 free(a->data); 95 } 96 free(a); 97 } 98 99 int 100 BUF_MEM_grow(BUF_MEM *str, size_t len) 101 { 102 return BUF_MEM_grow_clean(str, len); 103 } 104 105 int 106 BUF_MEM_grow_clean(BUF_MEM *str, size_t len) 107 { 108 char *ret; 109 size_t n; 110 111 if (str->max >= len) { 112 if (str->length >= len) 113 memset(&str->data[len], 0, str->length - len); 114 str->length = len; 115 return (len); 116 } 117 118 if (len > LIMIT_BEFORE_EXPANSION) { 119 BUFerror(ERR_R_MALLOC_FAILURE); 120 return 0; 121 } 122 123 n = (len + 3) / 3 * 4; 124 if ((ret = recallocarray(str->data, str->max, n, 1)) == NULL) { 125 BUFerror(ERR_R_MALLOC_FAILURE); 126 return (0); 127 } 128 str->data = ret; 129 str->max = n; 130 str->length = len; 131 132 return (len); 133 } 134 135 void 136 BUF_reverse(unsigned char *out, const unsigned char *in, size_t size) 137 { 138 size_t i; 139 140 if (in) { 141 out += size - 1; 142 for (i = 0; i < size; i++) 143 *out-- = *in++; 144 } else { 145 unsigned char *q; 146 char c; 147 q = out + size - 1; 148 for (i = 0; i < size / 2; i++) { 149 c = *q; 150 *q-- = *out; 151 *out++ = c; 152 } 153 } 154 } 155