1
2 NOTES FOR THE WINDOWS PLATFORMS
3 ===============================
4
5 Windows targets can be classified as "native", ones that use Windows API
6 directly, and "hosted" which rely on POSIX-compatible layer. "Native"
7 targets are VC-* (where "VC" stems from abbreviating Microsoft Visual C
8 compiler) and mingw[64]. "Hosted" platforms are Cygwin and MSYS[2]. Even
9 though the latter is not directly supported by OpenSSL Team, it's #1
10 popular choice for building MinGW targets. In the nutshell MinGW builds
11 are always cross-compiled. On Linux and Cygwin they look exactly as such
12 and require --cross-compile-prefix option. While on MSYS[2] it's solved
13 rather by placing gcc that produces "MinGW binary" code 1st on $PATH.
14 This is customarily source of confusion. "Hosted" applications "live" in
15 emulated filesystem name space with POSIX-y root, mount points, /dev
16 and even /proc. Confusion is intensified by the fact that MSYS2 shell
17 (or rather emulated execve(2) call) examines the binary it's about to
18 start, and if it's found *not* to be linked with MSYS2 POSIX-y thing,
19 command line arguments that look like filenames get translated from
20 emulated name space to "native". For example '/c/some/where' becomes
21 'c:\some\where', '/dev/null' - 'nul'. This creates an illusion that
22 there is no difference between MSYS2 shell and "MinGW binary", but
23 there is. Just keep in mind that "MinGW binary" "experiences" Windows
24 system in exactly same way as one produced by VC, and in its essence
25 is indistinguishable from the latter. (Which by the way is why
26 it's referred to in quotes here, as "MinGW binary", it's just as
27 "native" as it can get.)
28
29 Visual C++ builds, aka VC-*
30 ==============================
31
32 Requirement details
33 -------------------
34
35 In addition to the requirements and instructions listed in INSTALL,
36 these are required as well:
37
38 - Perl. We recommend ActiveState Perl, available from
39   https://www.activestate.com/ActivePerl. Another viable alternative
40   appears to be Strawberry Perl, http://strawberryperl.com.
41   You also need the perl module Text::Template, available on CPAN.
42   Please read NOTES.PERL for more information.
43
44 - Microsoft Visual C compiler. Since we can't test them all, there is
45   unavoidable uncertainty about which versions are supported. Latest
46   version along with couple of previous are certainly supported. On
47   the other hand oldest one is known not to work. Everything between
48   falls into best-effort category.
49
50 - Netwide Assembler, aka NASM, available from https://www.nasm.us,
51   is required. Note that NASM is the only supported assembler. Even
52   though Microsoft provided assembler is NOT supported, contemporary
53   64-bit version is exercised through continuous integration of
54   VC-WIN64A-masm target.
55
56
57 Installation directories
58 ------------------------
59
60 The default installation directories are derived from environment
61 variables.
62
63 For VC-WIN32, the following defaults are use:
64
65     PREFIX:      %ProgramFiles(x86)%\OpenSSL
66     OPENSSLDIR:  %CommonProgramFiles(x86)%\SSL
67
68 For VC-WIN64, the following defaults are use:
69
70     PREFIX:      %ProgramW6432%\OpenSSL
71     OPENSSLDIR:  %CommonProgramW6432%\SSL
72
73 Should those environment variables not exist (on a pure Win32
74 installation for examples), these fallbacks are used:
75
76     PREFIX:      %ProgramFiles%\OpenSSL
77     OPENSSLDIR:  %CommonProgramFiles%\SSL
78
79 ALSO NOTE that those directories are usually write protected, even if
80 your account is in the Administrators group.  To work around that,
81 start the command prompt by right-clicking on it and choosing "Run as
82 Administrator" before running 'nmake install'.  The other solution
83 is, of course, to choose a different set of directories by using
84 --prefix and --openssldir when configuring.
85
86 mingw and mingw64
87 =================
88
89 * MSYS2 shell and development environment installation:
90
91   Download MSYS2 from https://msys2.github.io/ and follow installation
92   instructions. Once up and running install even make, perl, (git if
93   needed,) mingw-w64-i686-gcc and/or mingw-w64-x86_64-gcc. You should
94   have corresponding MinGW items on your start menu, use *them*, not
95   generic MSYS2. As implied in opening note, difference between them
96   is which compiler is found 1st on $PATH. At this point ./config
97   should recognize correct target, roll as if it was Unix...
98
99 * It is also possible to build mingw[64] on Linux or Cygwin by
100   configuring with corresponding --cross-compile-prefix= option. For
101   example
102
103     ./Configure mingw --cross-compile-prefix=i686-w64-mingw32- ...
104
105   or
106
107     ./Configure mingw64 --cross-compile-prefix=x86_64-w64-mingw32- ...
108
109   This naturally implies that you've installed corresponding add-on
110   packages.
111
112 Independently of the method chosen to build for mingw, the installation
113 paths are similar to those used when building with VC-* targets, except
114 that in case the fallbacks mentioned there aren't possible (typically
115 when cross compiling on Linux), the paths will be the following:
116
117 For mingw:
118
119     PREFIX:      C:/Program Files (x86)/OpenSSL
120     OPENSSLDIR   C:/Program Files (x86)/Common Files/SSL
121
122 For mingw64:
123
124     PREFIX:      C:/Program Files/OpenSSL
125     OPENSSLDIR   C:/Program Files/Common Files/SSL
126
127 Linking your application
128 ========================
129
130 This section applies to all "native" builds.
131
132 If you link with static OpenSSL libraries then you're expected to
133 additionally link your application with WS2_32.LIB, GDI32.LIB,
134 ADVAPI32.LIB, CRYPT32.LIB and USER32.LIB. Those developing
135 noninteractive service applications might feel concerned about
136 linking with GDI32.LIB and USER32.LIB, as they are justly associated
137 with interactive desktop, which is not available to service
138 processes. The toolkit is designed to detect in which context it's
139 currently executed, GUI, console app or service, and act accordingly,
140 namely whether or not to actually make GUI calls. Additionally those
141 who wish to /DELAYLOAD:GDI32.DLL and /DELAYLOAD:USER32.DLL and
142 actually keep them off service process should consider implementing
143 and exporting from .exe image in question own _OPENSSL_isservice not
144 relying on USER32.DLL. E.g., on Windows Vista and later you could:
145
146	__declspec(dllexport) __cdecl BOOL _OPENSSL_isservice(void)
147	{   DWORD sess;
148	    if (ProcessIdToSessionId(GetCurrentProcessId(),&sess))
149	        return sess==0;
150	    return FALSE;
151	}
152
153 If you link with OpenSSL .DLLs, then you're expected to include into
154 your application code small "shim" snippet, which provides glue between
155 OpenSSL BIO layer and your compiler run-time. See the OPENSSL_Applink
156 manual page for further details.
157
158 Cygwin, "hosted" environment
159 ============================
160
161 Cygwin implements a Posix/Unix runtime system (cygwin1.dll) on top of the
162 Windows subsystem and provides a bash shell and GNU tools environment.
163 Consequently, a make of OpenSSL with Cygwin is virtually identical to the
164 Unix procedure.
165
166 To build OpenSSL using Cygwin, you need to:
167
168 * Install Cygwin (see https://cygwin.com/)
169
170 * Install Cygwin Perl and ensure it is in the path. Recall that
171   as least 5.10.0 is required.
172
173 * Run the Cygwin bash shell
174
175 Apart from that, follow the Unix instructions in INSTALL.
176
177 NOTE: "make test" and normal file operations may fail in directories
178 mounted as text (i.e. mount -t c:\somewhere /home) due to Cygwin
179 stripping of carriage returns. To avoid this ensure that a binary
180 mount is used, e.g. mount -b c:\somewhere /home.
181