crypto/libressl/ssl/tls_content.c

   1 /* $OpenBSD: tls_content.c,v 1.1 2021/09/04 16:26:12 jsing Exp $ */
   2 /*
   3  * Copyright (c) 2020 Joel Sing <jsing@openbsd.org>
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include <stdlib.h>
  19 #include <string.h>
  20
  21 #include "tls_content.h"
  22
  23 /* Content from a TLS record. */
  24 struct tls_content {
  25         uint8_t type;
  26         uint16_t epoch;
  27
  28         const uint8_t *data;
  29         size_t len;
  30         CBS cbs;
  31 };
  32
  33 struct tls_content *
  34 tls_content_new(void)
  35 {
  36         return calloc(1, sizeof(struct tls_content));
  37 }
  38
  39 void
  40 tls_content_clear(struct tls_content *content)
  41 {
  42         freezero((void *)content->data, content->len);
  43         memset(content, 0, sizeof(*content));
  44 }
  45
  46 void
  47 tls_content_free(struct tls_content *content)
  48 {
  49         if (content == NULL)
  50                 return;
  51
  52         tls_content_clear(content);
  53
  54         freezero(content, sizeof(struct tls_content));
  55 }
  56
  57 CBS *
  58 tls_content_cbs(struct tls_content *content)
  59 {
  60         return &content->cbs;
  61 }
  62
  63 int
  64 tls_content_equal(struct tls_content *content, const uint8_t *buf, size_t n)
  65 {
  66         return CBS_mem_equal(&content->cbs, buf, n);
  67 }
  68
  69 size_t
  70 tls_content_remaining(struct tls_content *content)
  71 {
  72         return CBS_len(&content->cbs);
  73 }
  74
  75 uint8_t
  76 tls_content_type(struct tls_content *content)
  77 {
  78         return content->type;
  79 }
  80
  81 int
  82 tls_content_dup_data(struct tls_content *content, uint8_t type,
  83     const uint8_t *data, size_t data_len)
  84 {
  85         uint8_t *dup;
  86
  87         if ((dup = calloc(1, data_len)) == NULL)
  88                 return 0;
  89         memcpy(dup, data, data_len);
  90
  91         tls_content_set_data(content, type, dup, data_len);
  92
  93         return 1;
  94 }
  95
  96 uint16_t
  97 tls_content_epoch(struct tls_content *content)
  98 {
  99         return content->epoch;
 100 }
 101
 102 void
 103 tls_content_set_epoch(struct tls_content *content, uint16_t epoch)
 104 {
 105         content->epoch = epoch;
 106 }
 107
 108 void
 109 tls_content_set_data(struct tls_content *content, uint8_t type,
 110     const uint8_t *data, size_t data_len)
 111 {
 112         tls_content_clear(content);
 113
 114         content->type = type;
 115         content->data = data;
 116         content->len = data_len;
 117
 118         CBS_init(&content->cbs, content->data, content->len);
 119 }
 120
 121 static ssize_t
 122 tls_content_read_internal(struct tls_content *content, uint8_t *buf, size_t n,
 123     int peek)
 124 {
 125         if (n > CBS_len(&content->cbs))
 126                 n = CBS_len(&content->cbs);
 127
 128         /* XXX - CBS_memcpy? CBS_copy_bytes? */
 129         memcpy(buf, CBS_data(&content->cbs), n);
 130
 131         if (!peek) {
 132                 if (!CBS_skip(&content->cbs, n))
 133                         return -1;
 134         }
 135
 136         return n;
 137 }
 138
 139 ssize_t
 140 tls_content_peek(struct tls_content *content, uint8_t *buf, size_t n)
 141 {
 142         return tls_content_read_internal(content, buf, n, 1);
 143 }
 144
 145 ssize_t
 146 tls_content_read(struct tls_content *content, uint8_t *buf, size_t n)
 147 {
 148         return tls_content_read_internal(content, buf, n, 0);
 149 }