golang

#!/usr/bin/env bash
##############################################################################
#
# golang
# -------------------
# Install or update Go language.
#
# Download Go source tarball and SHA1 hash from https://code.google.com. If
# hashcheck is okay, install and setup Go in /usr/local/go, and modify the
# system default $PATH to include Go's location by appending it to
# /etc/profile.
#
# For x86 64- and 32- bit Linux, only. Should work on all distros, except for
# RHEL and CentOS.
#
# :authors: Isis Agora Lovecruft, 0xa3adb67a2cdb8b35
# :date:    3 September 2012
# :version: 0.0.6
#
##############################################################################

set -eET

GO_VERSION="1.4.1"
USER_AGENT='Mozilla/5.0 (Windows NT 6.1; rv:31.0) Gecko/20100101 Firefox/31.0'
contact_name=isis
contact_host=patternsinthevoid.net
contact="${contact_name}@${contact_host}"

function usage ()
{
    printf "Usage: %s [options]\n\n" $(basename $0)
    printf "Options:\n"
    printf "\tinstall           Install Go ${GO_VERSION}\n"
    printf "\treinstall         Update Go to ${GO_VERSION}\n"
    printf "\tpath              Export PATH to Go & GoTools\n"
    printf "\ttor               Wrap network-related commands with torsocks\n"
    cat <<EOF

Additional Info:
    The “install” and “path” options will append to /etc/profile. This is
part of the Go installation instructions; it simply configures your GOPATH
and GOROOT environment variables so that you can start using Go.

    The “reinstall” option assumes you've already correctly configured your
PATH in order to use Go. If you already have a Go interpreter installed, or
you've already configured your environment, be sure to choose the “reinstall”
option, else you'll end up with Go in your PATH twice!
EOF
}

## wget is such a piece of shit
googlecode_cert=${HOME}/go.googlecode.com.pem
cat > $googlecode_cert<<EOF
# Certificate chain
#  0 s:/C=US/ST=California/L=Mountain View/O=Google Inc/CN=*.googlecode.com
#    i:/C=US/O=Google Inc/CN=Google Internet Authority
#  1 s:/C=US/O=Google Inc/CN=Google Internet Authority
#    i:/C=US/O=Equifax/OU=Equifax Secure Certificate Authority
# ---
# subject=/C=US/ST=California/L=Mountain View/O=Google Inc/CN=*.googlecode.com
# issuer=/C=US/O=Google Inc/CN=Google Internet Authority
#
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
EOF

google_cert=${HOME}/code.google.com.pem
cat > $google_cert <<EOF
# Certificate chain
#  0 s:/C=US/ST=California/L=Mountain View/O=Google Inc/CN=*.google.com
#    i:/C=US/O=Google Inc/CN=Google Internet Authority
#  1 s:/C=US/O=Google Inc/CN=Google Internet Authority
#    i:/C=US/O=Equifax/OU=Equifax Secure Certificate Authority
# ---
# subject=/C=US/ST=California/L=Mountain View/O=Google Inc/CN=*.google.com
# issuer=/C=US/O=Google Inc/CN=Google Internet Authority
#
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----
EOF

# $1: (bool) USE_WITH_TOR
function install_go ()
{
    OUR_ARCH=$(uname -m)
    FILE="https://golang.org/dl/"

    if [[ "$OUR_ARCH" == "x86_64" ]]; then
        ARCH_STRING=".linux-amd64.tar.gz"
    elif [[ "$OUR_ARCH" == "i686" ]]; then
        ARCH_STRING=".linux-386.tar.gz"
    else
        printf "Unsupported architecture. Must be 64-bit or 32-bit.\n"
        exit 1
    fi

    save_file=${GO_VERSION}${ARCH_STRING}
    tarball=${FILE}$save_file
    details=${FILE}

    GO_SOURCE=${HOME}/go${save_file}
    HTML_PAGE=${HOME}/go${GO_VERSION}.tar.gz.html

    if ! test -f "$GO_SOURCE" ; then
        if test -n "$tarball"; then
            printf "Downloading Go from:\n"
            printf "\t%s\n" ${tarball}
            if [[ "${USE_WITH_TOR}" == 1 ]]; then
                cd ${HOME} && \
                    torsocks wget -q --progress=bar -U $USER_AGENT \
                    --secure-protocol=TLSv1 --ca-certificate=$googlecode_cert \
                    -O ${GO_SOURCE} ${tarball}
            else
                cd ${HOME} && \
                    wget -q --timestamping --progress=bar -U $USER_AGENT \
                    --secure-protocol=TLSv1 --ca-certificate=$googlecode_cert \
                    -O ${GO_SOURCE} ${tarball}
            fi
        else
            printf "Error determining correct download...exiting...\n"
            unset USE_WITH_TOR
            exit 1
        fi
    else
        printf "Download already completed, attempting to resume install.\n"
    fi

    printf "Getting reported SHA1 from:\n\t%s\n" ${details}
    if [[ "${USE_WITH_TOR}" == 1 ]]; then
        cd ${HOME} && \
            torsocks wget --progress=bar -U "$USER_AGENT" \
            --secure-protocol=TLSv1 --ca-certificate=$google_cert \
            -O $HTML_PAGE ${details}
    else
        cd ${HOME} && \
            wget --progress=bar -U "$USER_AGENT" \
            --secure-protocol=TLSv1 --ca-certificate=$google_cert \
            -O $HTML_PAGE ${details}
    fi

    unset USE_WITH_TOR

    theirs=${HOME}/go_reported_hash
    ours=${HOME}/go_our_hash

    printf "Checking SHA1 hash of downloaded source...\n"
    grep -A6 "$save_file" $HTML_PAGE | grep -oE "[a-z0-9]{40}" | cat > $theirs
    sha1sum $GO_SOURCE | cut -d " " -f 1 > $ours

    printf "Reported SHA1 from Google Code: %s\n" $(cat $theirs )
    printf "Computed SHA1 from download:    %s\n" $(cat $ours )

    HASHDIFF=`diff ${theirs} ${ours}`
    if [[ "$HASHDIFF" == "" ]]; then
        printf "Installing GoTools ...\n"
        printf "Because unpacking the tarball into /usr/local requires root,\n"
        printf "you will be prompted for your sudo password.\n"
        sudo -- tar -C /usr/local -xzf $GO_SOURCE
        if test "$?" -eq 0 ; then
            printf "Installation successful!\n"
        fi
    else
        printf "WARNING: shasums do not match! Aborting installation...\n"
        MISMATCH=
    fi

    printf "Cleaning up...\n"
    for file in $theirs $ours $HTML_PAGE $GO_SOURCE \
        $googlecode_cert $google_cert ; do
        if test -f "$file" -a -O "$file" ; then rm $file ; fi
    done

    if test -v MISMATCH ; then printf "Exiting...\n" ; exit 1 ; fi

    unset MISMATCH HASHDIFF OUR_ARCH ARCH_STRING FILE DOWN GO_SOURCE HTML_PAGE
}

function export_paths ()
{
    if [ $(id -u) -eq 0 ]; then
        printf
        printf "Modifying system \$PATH to include Go..."
        cat >> /etc/profile<<EOF
## Path to GoTools
export GOROOT=/usr/local/go
export PATH=$PATH:$GOROOT/bin
EOF
        printf "Successfully updated \$PATH in /etc/profile."
    else
        printf
        printf "Modifying user \$PATH..."
        cat >> $HOME/.profile<<FIN
## Path to GoTools
## place the following in /etc/profile to enable Go for all users:
export GOROOT=/usr/local/go
export PATH=$PATH:$GOROOT/bin
FIN
        printf "Successfully updated \$PATH in ${HOME}/.profile..."
    fi
}

function root_check ()
{
    if [ $(id -u) -ne 0 ]; then
        printf "Must be run as root."
        exit 1
    fi
}

function os_check ()
{
    if [ $(uname) != "Linux" ]; then
        printf "Sorry, this only works for Linux."
        exit 1
    fi
}

function go_check ()
{
    if test -n "$(which go)" ; then
        current=$(go version | cut -d " " -f 3 | cut -b 3- )
        printf "Found previous Go installation. Version: %s\n" ${current}
        if test -d /usr/local/go ; then
            if [[ "$current" == "${GO_VERSION}" ]] ; then
                printf "Already up to date!\n"
                exit 0
            elif [[ "$current" > "${GO_VERSION}" ]] ; then
                printf "Oops! You've got Go %s, " ${current}
                printf "while we've got Go %s.\n" $GO_VERSION
                printf "Please mailto:%s and tell Isis to " $contact
                printf "update this script!\n"
            else
                printf "Updating Go to version %s...\n" $GO_VERSION
            fi
        fi
    fi
}

function mercurial_check ()
{
    if test -z "$(which hg)" ; then
        cat <<EOF
Go requires mercurial. Please use your distro's package manager to obtain
mercurcial first. Exiting...
EOF
    exit 1
    fi
}

function tor_check ()
{
    tpo='https://www.torproject.org/download'
    tsocks='https://gitweb.torproject.org/torsocks'
    newtsocks='https://github.com/dgoulet/torsocks'

    printf "Checking to see if tor is installed..."
    if test -z "$(which tor)" ; then
        FAIL=1
        cat <<EOF
It seems you don't have tor installed! If your distribution doesn't package
it, you can download tor from the Tor Project website:
    $tpo
EOF
    else
        printf "OK\n"
    fi

    printf "Checking to see if torsocks is installed..."
    if test -z "$(which torsocks)" ; then
        FAIL=1
        cat <<EOF
It seems you don't have torsocks installed!

Unfortunately, if your distribution doesn't already provide a package for it,
you'll likely need to build it from source.

The official Tor Project repository for the older version of torsocks is here:
    $tsocks

However, the older torsocks is occaisionally known to leak DNS queries and
potentially some other types of traffic, which can deanonymise you. For this
reason, torsocks was recently rewritten. The newer version *should* be safer,
but we're not making any promises yet. (Otherwise, we would have merged it
into the official repository!) However, if you are feeling slightly more
adventurous, and would like to assist us in testing, please consider
installing the newer torsocks, which can be found here:
    $newtsocks
EOF
    else
        printf "OK\n"
    fi

    test -n "$FAIL" && exit 2
    unset FAIL
}

function bad_opts_check ()
{
    if test "$DO_INSTALL" -eq 1 -a "$DO_REINSTALL" -eq 1 ; then
        printf "ERROR: We can't install and reinstall at the same time.\n"
        printf "       One or the other; pick your poison, buddy!\n\n"
        printf "Exiting...\n"
        exit 2
    fi
}

[[ "$#" > 0 ]] || { usage; exit 1; };

USE_WITH_TOR=0
DO_INSTALL=0
DO_REINSTALL=0

while [[ "x$1" != "x" ]]; do
    case $1 in
        install )
            DO_INSTALL=1
            shift
            ;;
        reinstall )
            DO_REINSTALL=1
            shift
            ;;
        path )
            os_check
            export_paths
            exit 0
            ;;
        tor )
            tor_check
            USE_WITH_TOR=1
            shift
            ;;
        * )
            usage
            exit 1
            ;;
    esac
done

if ! test "$DO_INSTALL" -eq 1 -o "$DO_REINSTALL" -eq 1 ; then
    usage
    exit 1
fi

if test "$DO_INSTALL" -eq 1 -o "$DO_REINSTALL" -eq 1 ; then
    #root_check
    bad_opts_check
    mercurial_check
    os_check
    go_check
    install_go $USE_WITH_TOR
    clean_up
    if test "$DO_REINSTALL" -eq 1 ; then
        printf "\n\nRe-installation sucessfull!\n"
    elif test "$DO_INSTALL" -eq 1 ; then
        export_paths
        printf "\n\nInstallation successful!\n"
    fi
    cat <<EOF
To get started learning Go, you can check out an interactive tour:
    $ go get code.google.com/p/go-tour/gotour
Or, if you're feeling erudite, try chillaxing with this book:
    https://www.golang-book.com/
EOF
    unset tarball
    unset details
    exit 0
fi