Cryptlib/OpenSSL/crypto/bio/bss_fd.c

   1 /*
   2  * Copyright 1995-2016 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
  13 #include "bio_lcl.h"
  14
  15 #if defined(OPENSSL_NO_POSIX_IO)
  16 /*
  17  * Dummy placeholder for BIO_s_fd...
  18  */
  19 BIO *BIO_new_fd(int fd, int close_flag)
  20 {
  21     return NULL;
  22 }
  23
  24 int BIO_fd_non_fatal_error(int err)
  25 {
  26     return 0;
  27 }
  28
  29 int BIO_fd_should_retry(int i)
  30 {
  31     return 0;
  32 }
  33
  34 const BIO_METHOD *BIO_s_fd(void)
  35 {
  36     return NULL;
  37 }
  38 #else
  39 /*
  40  * As for unconditional usage of "UPLINK" interface in this module.
  41  * Trouble is that unlike Unix file descriptors [which are indexes
  42  * in kernel-side per-process table], corresponding descriptors on
  43  * platforms which require "UPLINK" interface seem to be indexes
  44  * in a user-land, non-global table. Well, in fact they are indexes
  45  * in stdio _iob[], and recall that _iob[] was the very reason why
  46  * "UPLINK" interface was introduced in first place. But one way on
  47  * another. Neither libcrypto or libssl use this BIO meaning that
  48  * file descriptors can only be provided by application. Therefore
  49  * "UPLINK" calls are due...
  50  */
  51 static int fd_write(BIO *h, const char *buf, int num);
  52 static int fd_read(BIO *h, char *buf, int size);
  53 static int fd_puts(BIO *h, const char *str);
  54 static int fd_gets(BIO *h, char *buf, int size);
  55 static long fd_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  56 static int fd_new(BIO *h);
  57 static int fd_free(BIO *data);
  58 int BIO_fd_should_retry(int s);
  59
  60 static const BIO_METHOD methods_fdp = {
  61     BIO_TYPE_FD, "file descriptor",
  62     fd_write,
  63     fd_read,
  64     fd_puts,
  65     fd_gets,
  66     fd_ctrl,
  67     fd_new,
  68     fd_free,
  69     NULL,
  70 };
  71
  72 const BIO_METHOD *BIO_s_fd(void)
  73 {
  74     return (&methods_fdp);
  75 }
  76
  77 BIO *BIO_new_fd(int fd, int close_flag)
  78 {
  79     BIO *ret;
  80     ret = BIO_new(BIO_s_fd());
  81     if (ret == NULL)
  82         return (NULL);
  83     BIO_set_fd(ret, fd, close_flag);
  84     return (ret);
  85 }
  86
  87 static int fd_new(BIO *bi)
  88 {
  89     bi->init = 0;
  90     bi->num = -1;
  91     bi->ptr = NULL;
  92     bi->flags = BIO_FLAGS_UPLINK; /* essentially redundant */
  93     return (1);
  94 }
  95
  96 static int fd_free(BIO *a)
  97 {
  98     if (a == NULL)
  99         return (0);
 100     if (a->shutdown) {
 101         if (a->init) {
 102             UP_close(a->num);
 103         }
 104         a->init = 0;
 105         a->flags = BIO_FLAGS_UPLINK;
 106     }
 107     return (1);
 108 }
 109
 110 static int fd_read(BIO *b, char *out, int outl)
 111 {
 112     int ret = 0;
 113
 114     if (out != NULL) {
 115         clear_sys_error();
 116         ret = UP_read(b->num, out, outl);
 117         BIO_clear_retry_flags(b);
 118         if (ret <= 0) {
 119             if (BIO_fd_should_retry(ret))
 120                 BIO_set_retry_read(b);
 121         }
 122     }
 123     return (ret);
 124 }
 125
 126 static int fd_write(BIO *b, const char *in, int inl)
 127 {
 128     int ret;
 129     clear_sys_error();
 130     ret = UP_write(b->num, in, inl);
 131     BIO_clear_retry_flags(b);
 132     if (ret <= 0) {
 133         if (BIO_fd_should_retry(ret))
 134             BIO_set_retry_write(b);
 135     }
 136     return (ret);
 137 }
 138
 139 static long fd_ctrl(BIO *b, int cmd, long num, void *ptr)
 140 {
 141     long ret = 1;
 142     int *ip;
 143
 144     switch (cmd) {
 145     case BIO_CTRL_RESET:
 146         num = 0;
 147     case BIO_C_FILE_SEEK:
 148         ret = (long)UP_lseek(b->num, num, 0);
 149         break;
 150     case BIO_C_FILE_TELL:
 151     case BIO_CTRL_INFO:
 152         ret = (long)UP_lseek(b->num, 0, 1);
 153         break;
 154     case BIO_C_SET_FD:
 155         fd_free(b);
 156         b->num = *((int *)ptr);
 157         b->shutdown = (int)num;
 158         b->init = 1;
 159         break;
 160     case BIO_C_GET_FD:
 161         if (b->init) {
 162             ip = (int *)ptr;
 163             if (ip != NULL)
 164                 *ip = b->num;
 165             ret = b->num;
 166         } else
 167             ret = -1;
 168         break;
 169     case BIO_CTRL_GET_CLOSE:
 170         ret = b->shutdown;
 171         break;
 172     case BIO_CTRL_SET_CLOSE:
 173         b->shutdown = (int)num;
 174         break;
 175     case BIO_CTRL_PENDING:
 176     case BIO_CTRL_WPENDING:
 177         ret = 0;
 178         break;
 179     case BIO_CTRL_DUP:
 180     case BIO_CTRL_FLUSH:
 181         ret = 1;
 182         break;
 183     default:
 184         ret = 0;
 185         break;
 186     }
 187     return (ret);
 188 }
 189
 190 static int fd_puts(BIO *bp, const char *str)
 191 {
 192     int n, ret;
 193
 194     n = strlen(str);
 195     ret = fd_write(bp, str, n);
 196     return (ret);
 197 }
 198
 199 static int fd_gets(BIO *bp, char *buf, int size)
 200 {
 201     int ret = 0;
 202     char *ptr = buf;
 203     char *end = buf + size - 1;
 204
 205     while ((ptr < end) && (fd_read(bp, ptr, 1) > 0) && (ptr[0] != '\n'))
 206         ptr++;
 207
 208     ptr[0] = '\0';
 209
 210     if (buf[0] != '\0')
 211         ret = strlen(buf);
 212     return (ret);
 213 }
 214
 215 int BIO_fd_should_retry(int i)
 216 {
 217     int err;
 218
 219     if ((i == 0) || (i == -1)) {
 220         err = get_last_sys_error();
 221
 222         return (BIO_fd_non_fatal_error(err));
 223     }
 224     return (0);
 225 }
 226
 227 int BIO_fd_non_fatal_error(int err)
 228 {
 229     switch (err) {
 230
 231 # ifdef EWOULDBLOCK
 232 #  ifdef WSAEWOULDBLOCK
 233 #   if WSAEWOULDBLOCK != EWOULDBLOCK
 234     case EWOULDBLOCK:
 235 #   endif
 236 #  else
 237     case EWOULDBLOCK:
 238 #  endif
 239 # endif
 240
 241 # if defined(ENOTCONN)
 242     case ENOTCONN:
 243 # endif
 244
 245 # ifdef EINTR
 246     case EINTR:
 247 # endif
 248
 249 # ifdef EAGAIN
 250 #  if EWOULDBLOCK != EAGAIN
 251     case EAGAIN:
 252 #  endif
 253 # endif
 254
 255 # ifdef EPROTO
 256     case EPROTO:
 257 # endif
 258
 259 # ifdef EINPROGRESS
 260     case EINPROGRESS:
 261 # endif
 262
 263 # ifdef EALREADY
 264     case EALREADY:
 265 # endif
 266         return (1);
 267         /* break; */
 268     default:
 269         break;
 270     }
 271     return (0);
 272 }
 273 #endif