Where to find FreeBSD sha256 utility source code - freebsd

FreeBSD provides set of utilities for computing SHA-2 hashes (sha256, sha512, etc). I want to find their source code. I don't need source code of the SHA-256 hash function itself, but I am looking for source code of the command-line utility, i.e. part which processes command-line options, input files, etc. I've cloned latest FreeBSD source code from the GitHub-based mirror repo, and searched for "sha256" over the whole repo, and it gave me a lot of matches, but still I couldn't find that exact one. Please point me, where I can find it, if you know. Note: please do not point me to Linux/GNU alternative, sha256sum, I am interested exactly in the code of the FreeBSD sha256 (and friends like sha384, sha512) utility.

The command line utility is md5, but the same executable has many different names. See md5(1). The source code is located at src/sbin/md5.
It uses a number of functions from the libmd library located at src/lib/libmd, but the crypto code seems to be in src/sys/crypto/sha2.

By default, the hash utilities come from OpenSSL in the base system. For example
$ less /usr/src/crypto/openssl/crypto/sha/sha256.c
/*
* Copyright 2004-2016 The OpenSSL Project Authors. All Rights Reserved.
*
...
You can upgrade the utilities from ports. In this case, you can find the source in /usr/ports. For example
$ cd /usr/ports/security/openssl
$ make fetch
$ make extract
$ less /usr/ports/security/openssl/work/openssl-1.1.1l/crypto/sha/sha256.c
/*
* Copyright 2004-2016 The OpenSSL Project Authors. All Rights Reserved.
*
...

Related

What exactly is the difference between fuse2 and fuse3?

FUSE = Filesystem in user space recommends that distros package both a fuse2 and a fuse3 (see here) and indeed they do.
What exactly is the reason for this? Is it just that the init code in fuse3 is different?
The release notes for libfuse 3.0.0 appear comprehensive. Read below the heading 'Changes (since FUSE 2.9)'. Functions have been renamed for clarity, functions dropped and parameters tidied up. Here are a few examples from the release notes to give a flavour:
The fuse_lowlevel_new function has been renamed to
fuse_session_new and no longer interprets the --version or --help
options
fuse_loop(), fuse_loop_mt(), fuse_session_loop() and fuse_session_loop_mt() now return more detailed error codes instead of just -1. See the documentation of fuse_session_loop() for details
There are new fuse_session_unmount and fuse_session_mount
functions that should be used in the low-level API. The fuse_mount
and fuse_unmount functions should be used with the high-level API
only
The fuse_invalidate function has been removed
Installing libfuse2 alongside libfuse3 allows applications using libfuse2 to keep working without needing to be updated straight away.

How to find which Yocto Project recipe populates a particular file on an image root filesystem

I work with the Yocto Project quite a bit and a common challenge is determining why (or from what recipe) a file has been included on the rootfs. This is something that can hopefully be derived from the build system's environment, log & meta data. Ideally, a set of commands would allow linking a file back to a source (ie. recipe).
My usual strategy is to perform searches on the meta data (e.g. grep -R filename ../layers/*) and searches on the internet of said filenames to find clues of possible responsible recipes. However, this is not always very effective. In many cases, filenames are not explicitly stated within a recipe. Additionally, there are many cases where a filename is provided by multiple recipes which leads to additional work to find which recipe ultimately supplied it. There are of course many other clues available to find the answer. Regardless, this investigation is often quite laborious when it seems the build system should have enough information to make resolving the answer simple.
This is exact use case for oe-pkgdata-util script and its subcommand find-path. That script is part of openembedded-core.
See this example (executed in OE build environment, i.e. bitbake works):
tom#pc:~/oe/build> oe-pkgdata-util find-path /lib/ld-2.24.so
glibc: /lib/ld-2.24.so
You can clearly see that this library belongs to glibc recipe.
oe-pkgdata-util has more useful subcommands to see information about packages and recipes, it worth to check the --help.
If you prefer a graphical presentation, the Toaster web UI will also show you this, plus dependency information.
The candidate files deployed for each recipe are placed in each $WORKDIR/image
So you can cd to
$ cd ${TMPDIR}/work/${MULTIMACH_TARGET_SYS}
and perform a
$ find . -path '*/image/*/fileYouAreLookingFor'
from the result you should be able to infer the ${PN} of the recipe which deploys such file.
For example:
$ find . -path '*/image/*/mc'
./bash-completion/2.4-r0/image/usr/share/bash-completion/completions/mc
./mc/4.8.18-r0/image/usr/share/mc
./mc/4.8.18-r0/image/usr/bin/mc
./mc/4.8.18-r0/image/usr/libexec/mc
./mc/4.8.18-r0/image/etc/mc

Where can I find the source code for EVP_aes_256_cbc?

I need the source code of the OpenSSL API functions for EVP encryption, like EVP_aes_256_cbc. After much searching, all I could find were the headers of the functions in openssl/evp.h, but no source code in a .c file.
Where can I find the source code?
You'll find the final CBC mode implementation in cbc128.c and AES itself in AES.c. Mind that the EVP are high level functions that could use an engine - for instance using a hardware module (HSM) - or AES-NI CPU instructions instead. Searching for a single source file is therefore bunk.
I need the source code of openssl api functions evp encription... "EVP_AES_256_CBC"...
There is no function EVP_AES_256_CBC:
$ cd openssl-1.0.1g
$ grep -R EVP_AES_256_CBC *
$
So searching for it should turn up no results.
where can I find the source code
As user3553031 pointed out, you can get the source code for OpenSSL at OpenSSL: Source, Tarballs.
What do you really want?

can an RPM spec file "include" other files?

Is there a kind of "include" directive in RPM spec? I couldn't find an answer by googling.
Motivation: I have a RPM spec template which the build process modifies with the version, revision and other build-specific data. This is done by sed currently. I think it would be cleaner if the spec would #include a build-specific definitions file, which would be generated by the build process, so I don't need to search and replace in the spec.
If there is no include, is there an idiomatic way to do this (quite common, I believe) task?
Sufficiently recent versions of rpmbuild certainly do support %include:
%include common.inc
Unfortunately, they aren't very smart about it -- there is no known set of directories, in which it will look for the requested files, for example. But it is there and variables are expanded, for example:
%include %{_topdir}/Common/common.inc
RPM does not support includes.
I have solved similar problems with either m4 macro processor or by just concatenating parts of spec (when the "include" was at the beginning).
If you only need to pass a few variables at build time, and not include several lines from another file, you can run
rpmbuild --define 'myvar SOMEVALUE' -bb myspec.spec
and you can use %myvar in the spec.
I faced this same issue recently. I wanted to define multiple sub-packages that were similar, but each varied just slightly (they were language-specific RPMs). I didn't want to repeat the same boiler-plate stuff for each sub-package.
Here's a generic version of what I did:
%define foo_spec() %{expand:%(cat '%{myloc}/main-foo.spec')}
%{foo_spec bar}
%{foo_spec baz}
%{foo_spec qux}
The use of %{expand} ensures that %(cat) is only executed a single time, when the macro is defined. The content of the main-foo.spec file is then three times, and each time %1 in the main-foo.spec file expands to each of bar, baz and qux, in turn, allowing me to treat it as a template. You could easily expand this to more than one parameter, if you have the need (I did not).
For the underlying issue, there maybe two additional solutions that are present in all rpm versions that I am aware of.
Subpackages
macro and rpmrc files.
Subpackages
Another alternative (and perhaps the "RPM way") is to use sub-packages. Maximum RPM also has information and examples of subpackages.
I think the question is trying to structure something like,
two spec files; say rpm_debug.spec and rpm_production.spec
both use %include common.spec
debug and production could also be client and server, etc. For the examples of redefining a variable, each subpackage can have it's own list of variables.
Limitations
The main advantage of subpackages is that only one build takes place; This may also be a disadvantage. The debug and production example may highlight this. That can be worked around using strip to create variants or compiling twice with different output; perhaps using VPATH with Gnu Make). Having to compile large packages and then only have simple variations, like with/without developer info, like headers, static libraries, etc. can make you appreciate this approach.
Macros and Rpmrc
Subpackages don't solve the problem of structural defines that you wish for an entire rootfs hierarchy, or larger collection of RPMs. We have rpmbuild --showrc for this. You can have a large amount of variables and macros defined by altering rpmrc and macros when you run rpm and rpmbuild. From the man page,
rpmrc Configuration
/usr/lib/rpm/rpmrc
/usr/lib/rpm/redhat/rpmrc
/etc/rpmrc
~/.rpmrc
Macro Configuration
/usr/lib/rpm/macros
/usr/lib/rpm/redhat/macros
/etc/rpm/macros
~/.rpmmacros
I think these two features can solve all the problems that %include can. However, %include is a familiar concept and was probably added to make rpm more full-featured and developer friendly.
Which version are you talking about? I currently have %include filename.txt in my spec file and it seems to work just like the C #include directive.
> rpmbuild --version
RPM version 4.8.1
You can include the *.inc files from the SOURCES directory (%_sourcedir):
Source1: common.inc
%include %{SOURCE1}
In this way they will go automatically into SRPMS.
I've used scripts (name your favorite) to take a template and create the spec file from that. Also, the %files tag can import a file that is created by another process, e.g. Python's bdist-rpm.

Using library with different names within autoconf

I am trying to build an application with OpenSync 0.4 (0.3.9 indeed) dependency.
In the project's configure.ac the opensync library is written as libopensync1. However, this doesn't build on my Gentoo system. Changing libopensync1 to libopensync does fix the issue for me.
I searched with Google and found that libopensync1 is used in some distributions, while libopensync in others. So how to resolve this issue in configure.ac?
Thanks.
The macro AC_SEARCH_LIBS does what you need. (There is much heated debate about whether or not pkg-config should ever be used. If you choose to rely on it, ptomato gives a reasonable approach.) Simply add this to your configure.ac:
AC_SEARCH_LIBS([osync_mapping_new],[opensync1 opensync],[],
[AC_MSG_ERROR([can't find opensync])])
This will first look for a library named opensync1; if
it doesn't find that, it will look for opensync.
The primary drawback of using pkg-config is that most projects that
rely on it do not actually check if the data provided by the .pc
file is reliable, so configure may succeed but a subsequent build
will fail. It is always possible for a user to set PKG_CONFIG=true
when running configure and completely eliminate all of the data
provided by any associated .pc files, setting LIBS, CFLAGS, etc by
hand the 'old-fashioned' way.
The primary drawback of not using pkg-config is that the user
has to set LIBS, CFLAGS, etc. the old-fashioned way. In practice,
this is pretty trivial, and all pkg-config has done is move the
data from a single CONFIG_SITE file to separately maintained
.pc files for each package.
If you do use PKG_MODULE_CHECK, follow it up with a call to
AC_CHECK_LIB or AC_SEARCH_LIBS to validate the data in whatever
.pc file was located by PKG_CHECK_MODULES
I'm assuming that the place at which this occurs inside your configure.ac is inside a PKG_CHECK_MODULES call.
Looking at the libopensync sources, it seems that libopensync1 is the newer name, and libopensync is the old name. So, we'll use pkg-config macros to look for the newer name unless it doesn't exist.
Put this in your configure.ac:
# Check if libopensync1 is known to pkg-config, and if not, look for libopensync instead
PKG_CHECK_EXISTS([libopensync1], [OPENSYNC=libopensync1], [OPENSYNC=libopensync])
Then later in your PKG_CHECK_MODULES call, replace libopensync1 with $OPENSYNC.

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