Module: OpenSSL::Buffering

Includes:
Enumerable
Included in:
SSL::SSLSocket
Defined in:
lib/openssl/buffering.rb

Overview

OpenSSL IO buffering mix-in module.

This module allows an OpenSSL::SSL::SSLSocket to behave like an IO.

You typically won’t use this module directly, you can see it implemented in OpenSSL::SSL::SSLSocket.

Defined Under Namespace

Classes: Buffer

Constant Summary collapse

BLOCK_SIZE =

Default size to read from or write to the SSLSocket for buffer operations.

1024*16

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#sync ⇒ Object

The “sync mode” of the SSLSocket.

See IO#sync for full details.



53
54
55
 
# File 'lib/openssl/buffering.rb', line 53

def sync
  @sync
end

Instance Method Details

#<<(s) ⇒ Object

Writes s to the stream. s will be converted to a String using .to_s method.



434
435
436
437
 
# File 'lib/openssl/buffering.rb', line 434

def <<(s)
  do_write(s)
  self
end

#close ⇒ Object

Closes the SSLSocket and flushes any unwritten data.



495
496
497
498
 
# File 'lib/openssl/buffering.rb', line 495

def close
  flush rescue nil
  sysclose
end

#each(eol = $/) ⇒ Object Also known as: each_line

Executes the block for every line in the stream where lines are separated by eol.

See also #gets



266
267
268
269
270
 
# File 'lib/openssl/buffering.rb', line 266

def each(eol=$/)
  while line = self.gets(eol)
    yield line
  end
end

#each_byte ⇒ Object

Calls the given block once for each byte in the stream.



307
308
309
310
311
 
# File 'lib/openssl/buffering.rb', line 307

def each_byte # :yields: byte
  while c = getc
    yield(c.ord)
  end
end

#eof? ⇒ Boolean Also known as: eof

Returns true if the stream is at file which means there is no more data to be read.

Returns:

  • (Boolean) 


338
339
340
341
 
# File 'lib/openssl/buffering.rb', line 338

def eof?
  fill_rbuff if !@eof && @rbuffer.empty?
  @eof && @rbuffer.empty?
end

#flush ⇒ Object

Flushes buffered data to the SSLSocket.



483
484
485
486
487
488
489
490
 
# File 'lib/openssl/buffering.rb', line 483

def flush
  osync = @sync
  @sync = true
  do_write ""
  return self
ensure
  @sync = osync
end

#getbyte ⇒ Object

call-seq:

ssl.getbyte => 81

Get the next 8bit byte from ‘ssl`. Returns `nil` on EOF



106
107
108
 
# File 'lib/openssl/buffering.rb', line 106

def getbyte
  read(1)&.ord
end

#getc ⇒ Object

Reads one character from the stream. Returns nil if called at end of file.



300
301
302
 
# File 'lib/openssl/buffering.rb', line 300

def getc
  read(1)
end

#gets(eol = $/, limit = nil, chomp: false) ⇒ Object

Reads the next “line” from the stream. Lines are separated by eol. If limit is provided the result will not be longer than the given number of bytes.

eol may be a String or Regexp.

Unlike IO#gets the line read will not be assigned to $_.

Unlike IO#gets the separator must be provided if a limit is provided.



238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
 
# File 'lib/openssl/buffering.rb', line 238

def gets(eol=$/, limit=nil, chomp: false)
  idx = @rbuffer.index(eol)
  until @eof
    break if idx
    fill_rbuff
    idx = @rbuffer.index(eol)
  end
  if eol.is_a?(Regexp)
    size = idx ? idx+$&.size : nil
  else
    size = idx ? idx+eol.size : nil
  end
  if size && limit && limit >= 0
    size = [size, limit].min
  end
  line = consume_rbuff(size)
  if chomp && line
    line.chomp!(eol)
  end
  line
end

#initialize ⇒ Object

Creates an instance of OpenSSL’s buffering IO module.



63
64
65
66
67
68
 
# File 'lib/openssl/buffering.rb', line 63

def initialize(*)
  super
  @eof = false
  @rbuffer = Buffer.new
  @sync = @io.sync
end

#print(*args) ⇒ Object

Writes args to the stream.

See IO#print for full details.



462
463
464
465
466
467
 
# File 'lib/openssl/buffering.rb', line 462

def print(*args)
  s = Buffer.new
  args.each{ |arg| s << arg.to_s }
  do_write(s)
  nil
end

#printf(s, *args) ⇒ Object

Formats and writes to the stream converting parameters under control of the format string.

See Kernel#sprintf for format string details.



475
476
477
478
 
# File 'lib/openssl/buffering.rb', line 475

def printf(s, *args)
  do_write(s % args)
  nil
end

#puts(*args) ⇒ Object

Writes args to the stream along with a record separator.

See IO#puts for full details.



444
445
446
447
448
449
450
451
452
453
454
455
 
# File 'lib/openssl/buffering.rb', line 444

def puts(*args)
  s = Buffer.new
  if args.empty?
    s << "\n"
  end
  args.each{|arg|
    s << arg.to_s
    s.sub!(/(?<!\n)\z/, "\n")
  }
  do_write(s)
  nil
end

#read(size = nil, buf = nil) ⇒ Object

Reads size bytes from the stream. If buf is provided it must reference a string which will receive the data.

See IO#read for full details.



122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
 
# File 'lib/openssl/buffering.rb', line 122

def read(size=nil, buf=nil)
  if size == 0
    if buf
      buf.clear
      return buf
    else
      return ""
    end
  end
  until @eof
    break if size && size <= @rbuffer.size
    fill_rbuff
  end
  ret = consume_rbuff(size) || ""
  if buf
    buf.replace(ret)
    ret = buf
  end
  (size && ret.empty?) ? nil : ret
end

#read_nonblock(maxlen, buf = nil, exception: true) ⇒ Object

Reads at most maxlen bytes in the non-blocking manner.

When no data can be read without blocking it raises OpenSSL::SSL::SSLError extended by IO::WaitReadable or IO::WaitWritable.

IO::WaitReadable means SSL needs to read internally so read_nonblock should be called again when the underlying IO is readable.

IO::WaitWritable means SSL needs to write internally so read_nonblock should be called again after the underlying IO is writable.

OpenSSL::Buffering#read_nonblock needs two rescue clause as follows:

# emulates blocking read (readpartial).
begin
  result = ssl.read_nonblock(maxlen)
rescue IO::WaitReadable
  IO.select([io])
  retry
rescue IO::WaitWritable
  IO.select(nil, [io])
  retry
end

Note that one reason that read_nonblock writes to the underlying IO is when the peer requests a new TLS/SSL handshake. See openssl the FAQ for more details. www.openssl.org/support/faq.html

By specifying a keyword argument exception to false, you can indicate that read_nonblock should not raise an IO::Wait*able exception, but return the symbol :wait_writable or :wait_readable instead. At EOF, it will return nil instead of raising EOFError.



207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
 
# File 'lib/openssl/buffering.rb', line 207

def read_nonblock(maxlen, buf=nil, exception: true)
  if maxlen == 0
    if buf
      buf.clear
      return buf
    else
      return ""
    end
  end
  if @rbuffer.empty?
    return sysread_nonblock(maxlen, buf, exception: exception)
  end
  ret = consume_rbuff(maxlen)
  if buf
    buf.replace(ret)
    ret = buf
  end
  ret
end

#readbyte ⇒ Object

Get the next 8bit byte. Raises EOFError on EOF

Raises:

  • (EOFError) 


111
112
113
114
 
# File 'lib/openssl/buffering.rb', line 111

def readbyte
  raise EOFError if eof?
  getbyte
end

#readchar ⇒ Object

Reads a one-character string from the stream. Raises an EOFError at end of file.

Raises:

  • (EOFError) 


317
318
319
320
 
# File 'lib/openssl/buffering.rb', line 317

def readchar
  raise EOFError if eof?
  getc
end

#readline(eol = $/) ⇒ Object

Reads a line from the stream which is separated by eol.

Raises EOFError if at end of file.

Raises:

  • (EOFError) 


291
292
293
294
 
# File 'lib/openssl/buffering.rb', line 291

def readline(eol=$/)
  raise EOFError if eof?
  gets(eol)
end

#readlines(eol = $/) ⇒ Object

Reads lines from the stream which are separated by eol.

See also #gets



278
279
280
281
282
283
284
 
# File 'lib/openssl/buffering.rb', line 278

def readlines(eol=$/)
  ary = []
  while line = self.gets(eol)
    ary << line
  end
  ary
end

#readpartial(maxlen, buf = nil) ⇒ Object

Reads at most maxlen bytes from the stream. If buf is provided it must reference a string which will receive the data.

See IO#readpartial for full details.



149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
 
# File 'lib/openssl/buffering.rb', line 149

def readpartial(maxlen, buf=nil)
  if maxlen == 0
    if buf
      buf.clear
      return buf
    else
      return ""
    end
  end
  if @rbuffer.empty?
    begin
      return sysread(maxlen, buf)
    rescue Errno::EAGAIN
      retry
    end
  end
  ret = consume_rbuff(maxlen)
  if buf
    buf.replace(ret)
    ret = buf
  end
  ret
end

#ungetc(c) ⇒ Object

Pushes character c back onto the stream such that a subsequent buffered character read will return it.

Unlike IO#getc multiple bytes may be pushed back onto the stream.

Has no effect on unbuffered reads (such as #sysread).



330
331
332
 
# File 'lib/openssl/buffering.rb', line 330

def ungetc(c)
  @rbuffer[0,0] = c.chr
end

#write(*s) ⇒ Object

Writes s to the stream. If the argument is not a String it will be converted using .to_s method. Returns the number of bytes written.



381
382
383
384
385
386
 
# File 'lib/openssl/buffering.rb', line 381

def write(*s)
  s.inject(0) do |written, str|
    do_write(str)
    written + str.bytesize
  end
end

#write_nonblock(s, exception: true) ⇒ Object

Writes s in the non-blocking manner.

If there is buffered data, it is flushed first. This may block.

write_nonblock returns number of bytes written to the SSL connection.

When no data can be written without blocking it raises OpenSSL::SSL::SSLError extended by IO::WaitReadable or IO::WaitWritable.

IO::WaitReadable means SSL needs to read internally so write_nonblock should be called again after the underlying IO is readable.

IO::WaitWritable means SSL needs to write internally so write_nonblock should be called again after underlying IO is writable.

So OpenSSL::Buffering#write_nonblock needs two rescue clause as follows.

# emulates blocking write.
begin
  result = ssl.write_nonblock(str)
rescue IO::WaitReadable
  IO.select([io])
  retry
rescue IO::WaitWritable
  IO.select(nil, [io])
  retry
end

Note that one reason that write_nonblock reads from the underlying IO is when the peer requests a new TLS/SSL handshake. See the openssl FAQ for more details. www.openssl.org/support/faq.html

By specifying a keyword argument exception to false, you can indicate that write_nonblock should not raise an IO::Wait*able exception, but return the symbol :wait_writable or :wait_readable instead.



425
426
427
428
 
# File 'lib/openssl/buffering.rb', line 425

def write_nonblock(s, exception: true)
  flush
  syswrite_nonblock(s, exception: exception)
end