lib/libcrypto/bio/bf_nbio.c

   1 /* $OpenBSD: bf_nbio.c,v 1.19 2015/02/07 13:19:15 doug 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 <errno.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62
  63 #include <openssl/bio.h>
  64
  65 /* BIO_put and BIO_get both add to the digest,
  66  * BIO_gets returns the digest */
  67
  68 static int nbiof_write(BIO *h, const char *buf, int num);
  69 static int nbiof_read(BIO *h, char *buf, int size);
  70 static int nbiof_puts(BIO *h, const char *str);
  71 static int nbiof_gets(BIO *h, char *str, int size);
  72 static long nbiof_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  73 static int nbiof_new(BIO *h);
  74 static int nbiof_free(BIO *data);
  75 static long nbiof_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
  76
  77 typedef struct nbio_test_st {
  78         /* only set if we sent a 'should retry' error */
  79         int lrn;
  80         int lwn;
  81 } NBIO_TEST;
  82
  83 static BIO_METHOD methods_nbiof = {
  84         .type = BIO_TYPE_NBIO_TEST,
  85         .name = "non-blocking IO test filter",
  86         .bwrite = nbiof_write,
  87         .bread = nbiof_read,
  88         .bputs = nbiof_puts,
  89         .bgets = nbiof_gets,
  90         .ctrl = nbiof_ctrl,
  91         .create = nbiof_new,
  92         .destroy = nbiof_free,
  93         .callback_ctrl = nbiof_callback_ctrl
  94 };
  95
  96 BIO_METHOD *
  97 BIO_f_nbio_test(void)
  98 {
  99         return (&methods_nbiof);
 100 }
 101
 102 static int
 103 nbiof_new(BIO *bi)
 104 {
 105         NBIO_TEST *nt;
 106
 107         if (!(nt = malloc(sizeof(NBIO_TEST))))
 108                 return (0);
 109         nt->lrn = -1;
 110         nt->lwn = -1;
 111         bi->ptr = (char *)nt;
 112         bi->init = 1;
 113         bi->flags = 0;
 114         return (1);
 115 }
 116
 117 static int
 118 nbiof_free(BIO *a)
 119 {
 120         if (a == NULL)
 121                 return (0);
 122         free(a->ptr);
 123         a->ptr = NULL;
 124         a->init = 0;
 125         a->flags = 0;
 126         return (1);
 127 }
 128
 129 static int
 130 nbiof_read(BIO *b, char *out, int outl)
 131 {
 132         int ret = 0;
 133         int num;
 134         unsigned char n;
 135
 136         if (out == NULL)
 137                 return (0);
 138         if (b->next_bio == NULL)
 139                 return (0);
 140
 141         BIO_clear_retry_flags(b);
 142
 143         arc4random_buf(&n, 1);
 144         num = (n & 0x07);
 145
 146         if (outl > num)
 147                 outl = num;
 148
 149         if (num == 0) {
 150                 ret = -1;
 151                 BIO_set_retry_read(b);
 152         } else {
 153                 ret = BIO_read(b->next_bio, out, outl);
 154                 if (ret < 0)
 155                         BIO_copy_next_retry(b);
 156         }
 157         return (ret);
 158 }
 159
 160 static int
 161 nbiof_write(BIO *b, const char *in, int inl)
 162 {
 163         NBIO_TEST *nt;
 164         int ret = 0;
 165         int num;
 166         unsigned char n;
 167
 168         if ((in == NULL) || (inl <= 0))
 169                 return (0);
 170         if (b->next_bio == NULL)
 171                 return (0);
 172         nt = (NBIO_TEST *)b->ptr;
 173
 174         BIO_clear_retry_flags(b);
 175
 176         if (nt->lwn > 0) {
 177                 num = nt->lwn;
 178                 nt->lwn = 0;
 179         } else {
 180                 arc4random_buf(&n, 1);
 181                 num = (n&7);
 182         }
 183
 184         if (inl > num)
 185                 inl = num;
 186
 187         if (num == 0) {
 188                 ret = -1;
 189                 BIO_set_retry_write(b);
 190         } else {
 191                 ret = BIO_write(b->next_bio, in, inl);
 192                 if (ret < 0) {
 193                         BIO_copy_next_retry(b);
 194                         nt->lwn = inl;
 195                 }
 196         }
 197         return (ret);
 198 }
 199
 200 static long
 201 nbiof_ctrl(BIO *b, int cmd, long num, void *ptr)
 202 {
 203         long ret;
 204
 205         if (b->next_bio == NULL)
 206                 return (0);
 207         switch (cmd) {
 208         case BIO_C_DO_STATE_MACHINE:
 209                 BIO_clear_retry_flags(b);
 210                 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 211                 BIO_copy_next_retry(b);
 212                 break;
 213         case BIO_CTRL_DUP:
 214                 ret = 0L;
 215                 break;
 216         default:
 217                 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 218                 break;
 219         }
 220         return (ret);
 221 }
 222
 223 static long
 224 nbiof_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
 225 {
 226         long ret = 1;
 227
 228         if (b->next_bio == NULL)
 229                 return (0);
 230         switch (cmd) {
 231         default:
 232                 ret = BIO_callback_ctrl(b->next_bio, cmd, fp);
 233                 break;
 234         }
 235         return (ret);
 236 }
 237
 238 static int
 239 nbiof_gets(BIO *bp, char *buf, int size)
 240 {
 241         if (bp->next_bio == NULL)
 242                 return (0);
 243         return (BIO_gets(bp->next_bio, buf, size));
 244 }
 245
 246 static int
 247 nbiof_puts(BIO *bp, const char *str)
 248 {
 249         if (bp->next_bio == NULL)
 250                 return (0);
 251         return (BIO_puts(bp->next_bio, str));
 252 }