:Manual section: 3 :Author: Kristian Lyngstøl :Date: 2016-03-16 :Version: 1.0.3
::
import digest;
digest.hmac_md5(<key>,<message>);
digest.hmac_sha1(<key>, <message>);
digest.hmac_sha256(<key>, <message));
digest.base64(<string>);
digest.base64url(<string>);
digest.base64url_nopad(<string>);
digest.base64_hex(<string>);
digest.base64url_hex(<string>);
digest.base64url_nopad_hex(<string>);
digest.base64_decode(<string>);
digest.base64url_decode(<string>);
digest.base64url_nopad_decode(<string>);
digest.version()
digest.hash_sha1(<string>);
digest.hash_sha224(<string>);
digest.hash_sha256(<string>);
digest.hash_sha384(<string>);
digest.hash_sha512(<string>);
digest.hash_gost(<string>);
digest.hash_md2(<string>);
digest.hash_md4(<string>);
digest.hash_md5(<string>);
digest.hash_crc32(<string>);
digest.hash_crc32b(<string>);
digest.hash_adler32(<string>);
digest.hash_haval128(<string>);
digest.hash_haval160(<string>);
digest.hash_haval192(<string>);
digest.hash_haval224(<string>);
digest.hash_haval256(<string>);
digest.hash_ripemd128(<string>);
digest.hash_ripemd160(<string>);
digest.hash_ripemd256(<string>);
digest.hash_ripemd320(<string>);
digest.hash_tiger(<string>);
digest.hash_tiger128(<string>);
digest.hash_tiger160(<string>);
digest.hash_snefru128(<string>);
digest.hash_snefru256(<string>);Varnish Module (vmod) for computing HMAC, message digests and working with base64.
All HMAC- and hash-functionality is provided by libmhash, while base64 is implemented locally.
Example VCL::
backend foo { ... };
import digest;
sub vcl_recv {
if (digest.hmac_sha256("key",req.http.x-data) != req.http.x-data-sig)
{
return (synth(401, "Naughty user!"));
}
}Prototype ::
digest.hmac_md5(<key>,<message>);
digest.hmac_sha1(<key>, <message>);
digest.hmac_sha256(<key>, <message));Returns String. Hex-encoded prepended with 0x. Description All the various hmac-functions work the same, but use a different hash mechanism. Example ::
set resp.http.x-data-sig =
digest.hmac_sha256("secretkey",resp.http.x-data);Prototype ::
digest.base64(<string>);
digest.base64url(<string>);
digest.base64url_nopad(<string>);Returns String Description Returns the base64-encoded version of the input-string. The base64url-variant uses base64 url-encoding (+/ replaced by -_) and the base64url_nopad does the same, but avoids adding padding. The latter is more commonly used, though an (allowed) exception to the RFC4648. Example ::
set resp.http.x-data-sig =
digest.base64({"content with
newline in it"});Prototype ::
digest.base64_hex(<string>);
digest.base64url_hex(<string>);
digest.base64url_nopad_hex(<string>);Returns String Description Returns the base64-encoded version of the hex encoded input-string. The input-string can start with an optional 0x. Input is hex-decoded into binary and the encoding is identical to base64, base64url, and base64url_nopad. Example ::
set resp.http.x-data-sig =
digest.base64_hex("0xdd26bfddf122c1055d4c");Prototype ::
digest.hash_sha1(<string>);
digest.hash_sha224(<string>);
digest.hash_sha256(<string>);
digest.hash_sha384(<string>);
digest.hash_sha512(<string>);
digest.hash_gost(<string>);
digest.hash_md2(<string>);
digest.hash_md4(<string>);
digest.hash_md5(<string>);
digest.hash_crc32(<string>);
digest.hash_crc32b(<string>);
digest.hash_adler32(<string>);
digest.hash_haval128(<string>);
digest.hash_haval160(<string>);
digest.hash_haval192(<string>);
digest.hash_haval224(<string>);
digest.hash_haval256(<string>);
digest.hash_ripemd128(<string>);
digest.hash_ripemd160(<string>);
digest.hash_ripemd256(<string>);
digest.hash_ripemd320(<string>);
digest.hash_tiger(<string>);
digest.hash_tiger128(<string>);
digest.hash_tiger160(<string>);
digest.hash_snefru128(<string>);
digest.hash_snefru256(<string>);Returns String Description Computes the digest/hash of the supplied, using the specified hash algorithm. If in doubt as to which to pick, use SHA256. For detailed discussions, see The Internet. Example ::
set resp.http.x-data-md5 =
digest.hash_md5(resp.http.x-data);Prototype ::
digest.base64_decode(<string>);
digest.base64url_decode(<string>);
digest.base64url_nopad_decode(<string>);Returns String Description Decodes the bas64 and base64url-encoded strings. All functions treat padding the same, meaning base64url_decode and base64url_nopad_decode are identical, but available for consistency and practicality. Example :: synthetic(digest.base64_decode(req.http.x-parrot));
Prototype ::
digest.version()Returns string Description Returns the string constant version-number of the digest vmod. Example ::
set resp.http.X-digest-version = digest.version();The source tree is based on autotools to configure the building, and
does also have the necessary bits in place to do functional unit tests
using the varnishtest tool.
Building requires the Varnish header files and uses pkg-config to find the necessary paths.
Usage::
./autogen.sh ./configure
If you have installed Varnish to a non-standard directory, call
autogen.sh and configure with PKG_CONFIG_PATH pointing to
the appropriate path. For example, when varnishd configure was called
with --prefix=$PREFIX, use
PKG_CONFIG_PATH=${PREFIX}/lib/pkgconfig export PKG_CONFIG_PATH
Make targets:
src/tests/*.vtcOriginal author: Kristian Lyngstøl opensource@varnish-software.com.
This Vmod was written for Media Norge, Schibsted and others.
The bulk of the functionality is acquired through libmhash.
No bugs at all!
If the key is NULL for hmac-functions, the function will fail and return NULL itself, and do no hmac-computation at all. This should be used as an indication of some greater flaw in your software/VCL. (I.e.: Your key should be under your control, not user-supplied without verification).
The base64url_nopad_decode() and base64url_decode() functions do not
differ much. The exception is that nopad_decode() does not know about
padding at all, and might get confused if the input actually is padded.