Module: WinCred

Defined in:
lib/wincred/wincred.rb,
lib/wincred/native.rb,
lib/wincred/conversion.rb

Overview

This module provides a high-level API for interations with the Windows Credential Manager

Defined Under Namespace

Modules: Conversion, Native

Class Method Summary collapse

Class Method Details

.delete_credential(target) ⇒ Object 



109
110
111
112
113
114
115
116
117
 
# File 'lib/wincred/wincred.rb', line 109

def delete_credential(target)
  delete_result = Native.CredDeleteW(
    target.encode('utf-16le'),
    Native::CRED_TYPE_GENERIC,
    Native::FLAGS_NONE,
  )

  raise "Delete from WinCred failed. Error code: #{Native.GetLastError}" if delete_result.zero?
end

.enumerate_credentials ⇒ Object 



25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
 
# File 'lib/wincred/wincred.rb', line 25

def enumerate_credentials
  pp_credentials = Fiddle::Pointer.new 0

  # Create 4-byte integer pointer to hold the returned cred count
  cred_count_ptr = Fiddle::Pointer.malloc(Fiddle::SIZEOF_LONG, Fiddle::RUBY_FREE)

  enum_result = Native.CredEnumerateW(
    nil,
    Native::FLAGS_NONE,
    cred_count_ptr,
    pp_credentials.ref,
  )

  if enum_result.zero?
    raise "Enumerate credentials in WinCred failed. Error code: #{Native.GetLastError}"
  end

  # Convert count bytes to Ruby int
  count = cred_count_ptr[0, 4].unpack('L').first

  # Convert memory struct array into Ruby array
  # RuboCop disabled rule here may be a valid find but this code is very fragile
  # and old.
  # rubocop:disable Performance/TimesMap
  count.times.map do |ndx|
    cred_ptr = (pp_credentials + (ndx * Fiddle::SIZEOF_VOIDP)).ptr
    cred = Native::CREDENTIALW.new(cred_ptr)
    cred_to_hash(cred)
  end
ensure
  # Free the credential memory
  Native.CredFree(pp_credentials) if pp_credentials
end

.exist?(target) ⇒ Boolean

Returns:

  • (Boolean) 


10
11
12
13
14
15
16
17
18
19
20
21
22
23
 
# File 'lib/wincred/wincred.rb', line 10

def exist?(target)
  cred_ptr = Fiddle::Pointer.new 0

  read_result = Native.CredReadW(
    target.encode('utf-16le'),
    Native::CRED_TYPE_GENERIC,
    Native::FLAGS_NONE,
    cred_ptr.ref,
  )

  read_result.positive?
ensure
  Native.CredFree(cred_ptr) if cred_ptr
end

.read_credential(target) ⇒ Object 



90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
 
# File 'lib/wincred/wincred.rb', line 90

def read_credential(target)
  cred_ptr = Fiddle::Pointer.new 0

  # We have to encode the target name for the Windows API call
  read_result = Native.CredReadW(
    target.encode('utf-16le'),
    Native::CRED_TYPE_GENERIC,
    Native::FLAGS_NONE,
    cred_ptr.ref,
  )

  raise "Read from WinCred failed. Error code: #{Native.GetLastError}" if read_result.zero?

  cred = Native::CREDENTIALW.new(cred_ptr)
  cred_to_hash(cred)
ensure
  Native.CredFree(cred_ptr) if cred_ptr
end

.write_credential(target:, username:, value:) ⇒ Object 



59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
 
# File 'lib/wincred/wincred.rb', line 59

def write_credential(
    target:,
    username:,
    value: # binary string
)

  if value.bytes.size != value.size
    raise "Write to WinCred failed. Value is not a binary string. Encoding is (#{value.encoding})."
  end

  cred = Native::CREDENTIALW.malloc

  cred.Flags = Native::FLAGS_NONE
  cred.Type = Native::CRED_TYPE_GENERIC
  cred.TargetName = target.encode('utf-16le')
  cred.Comment = ''
  cred.CredentialBlobSize = value.size
  cred.CredentialBlob = Fiddle::Pointer[value]
  cred.Persist = Native::CRED_PERSIST_LOCAL_MACHINE
  cred.AttributeCount = 0
  cred.Attributes = nil
  cred.TargetAlias = nil
  cred.UserName = username.encode('utf-16le')

  write_result = Native.CredWriteW(Fiddle::Pointer[cred], 0)

  raise "Write to WinCred failed. Error code: #{Native.GetLastError}" if write_result.zero?
ensure
  Fiddle.free(cred.to_i) if cred
end