#!/bin/sh
set -e -f ${DRY_RUN:+-n} -u
tool=$(readlink -e "${0%/*}")
. "$tool"/lib/rule.sh
. "$tool"/etc/vm.sh
TRACE=1

rule_help () { # SYNTAX: [--hidden]
	local hidden; [ ${1:+set} ] || hidden=set
	cat >&2 <<-EOF
		DESCRIPTION:
		  ce script regroupe des règles pour administrer la VM ($vm_fqdn)
		  _depuis_ une machine distante ;
		  il sert à la fois d'outil (aisément bidouillable)
		  et de documentation (préçise).
		  Voir \`$tool/vm_host'   pour les règles côté machine hôte ($vm_host).
		  Voir \`$tool/vm_hosted' pour les règles côté VM hébergée ($vm_fqdn).
		SYNTAX: $0 \$RULE \${RULE}_SYNTAX
		RULES:
		$(sed -ne "s/^rule_\(${hidden:+[^_]}[^ ]*\) () {\( *#.*\|\)/  \1\2/p" "$tool"/etc/vm.sh "$0")
		ENVIRONMENT:
		  TRACE # affiche les commandes avant leur exécution
		$(sed -ne 's/^readonly \([^ ][^ =]*\).*}\( *#.*\|\)$/\t$\1\2/p' "$tool"/etc/vm.sh "$0")
		EOF
 }

rule_git_configure () { # DESCRIPTION: configure ./.git correctement
	(
	cd "$tool"
	git remote rm host || true
	git remote add host $vm_host:src/vm
	git config --replace remote.host.push HEAD:refs/remotes/master
	git remote rm hosted || true
	git remote add hosted $vm_fqdn:src/vm
	git config --replace remote.hosted.push HEAD:refs/remotes/master
	git submodule update --init
	)
 }
rule_git_push () { # SYNTAX: {host|hosted} $git_push_options
	(
	cd "$tool"
	local remote=${1#remote=}; shift
	GIT_SSH=./lib/ssh git push -v "$remote" "$@"
	)
 }

rule_ssh () {
	"$tool"/lib/ssh $vm_fqdn "$@"
 }
rule_mosh () {
	mosh --ssh="$tool/lib/ssh ${ssh-}" -- $vm_fqdn "$@"
 }
rule__ssh_known_hosts_update () {
	rule ssh \
	 -o StrictHostKeyChecking=no \
	 -o CheckHostIP=no \
	 -o HashKnownHosts=no \
	 whoami
 }

rule__x509_site_key_decrypt () { # SYNTAX: $site
	local site="$1"; shift
	gpg --decrypt "$tool"/var/sec/x509/"$site"/key.pass.gpg |
	openssl rsa -passin 'stdin' \
	 -in  var/sec/x509/"$site"/key.pem \
	 -out '/dev/stdout'
 }

rule_luks_key_send () { # DESCRIPTION: envoie la clef de déchiffrement des partitions au démarrage de la VM.
	gpg --decrypt var/sec/luks/$vm_fqdn.key.gpg |
	"$tool"/lib/ssh root@$vm_fqdn "$@" \
	 -o CheckHostIP=no \
	 -o HostKeyAlias=init.$vm_fqdn \
	 tee /lib/cryptsetup/passfifo \>/dev/null
 }
rule_luks_key_backup () { # SYNTAX: ${gpg_options:---recipient $USER@} DESCRIPTION: sauvegarde localement les entêtes des partitions chiffrées.
	test "${*+set}" || set -- --recipient "$USER@"
	for part in root var home
	 do
		mkdir -p var/sec/luks
		rule ssh -l root ' \
			set -e -f -u;
			exec 2>/dev/null;
			tmp=$(mktemp -t "luks.'"$part"'.XXXXXXXX.tmp" --dry-run);
			cryptsetup luksHeaderBackup >/dev/null \
			 /dev/'"$vm_lvm_vg"'/'"$vm_lvm_lv"'_'"$part"' \
			 --header-backup-file "$tmp"; \
			cat "$tmp";
			shred >/dev/null --remove "$tmp"; \
		 ' |
		gpg "$@" --encrypt \
		 -o var/sec/luks/${vm_lvm_lv}_${part}.luks.gpg
	 done
 }

rule_gitolite_git () {
	(
	cd "$tool"/etc/gitolite
	GIT_SSH=../../lib/ssh \
	ssh-agent sh -c ' \
		SSH_ASKPASS='"$tool"'/lib/ssh-pass \
		SSH_ID=git \
		ssh-add '"$tool"'/var/sec/ssh/git </dev/null && \
		git '"$*"
	)
 }
rule_runit_configure () { # SYNTAX: $sv [...] -- $configure_options
	if test $# = 0
	 then
		set +x
		rule ssh sudo sv status \
		 $(sudo find /etc/sv \
		 -mindepth 1 -maxdepth 1 -type d \
		 -printf '%p\n' | sort)
	 else
		local services=
		while [ $# -gt 0 ]
		 do case $1 in
			 (--) shift; break;;
			 (*) services="$services $1"; shift;;
			 esac
		 done
		for sv in $(find "$tool"/etc/sv \
		 -mindepth 1 -maxdepth 1 -type d \
		 -false $(printf -- '-or -name %s\n' $services) \
		 -printf '%f\n')
		 do
			rule _runit_sv_configure "$sv" "$@"
		 done
	 fi
 }
rule__runit_sv_configure () { # SYNTAX: $sv $configure_options
	local sv="$1"; shift
	(
	test ! -r "$tool"/etc/sv/"$sv"/remote.sh ||
	.         "$tool"/etc/sv/"$sv"/remote.sh || return 1
	)
 }


rule_duplicity_configure () {
	subkey_caps="e s" \
	rule gpg_gen_key "backup+$vm_hostname@$vm_domainname" <<-EOF
		Name-Real: $vm_fqdn
		Name-Email: backup+$vm_hostname@$vm_domainname
		Name-Comment: (duplicity)
		Expire-Date: 0
		EOF
 }
rule_duplicity_key_send () {
	gpg --export-options export-reset-subkey-passwd \
	 --export-secret-subkeys "backup+$vm_hostname@$vm_domainname" |
	rule ssh gpg --import -
 }
rule_gpg () { # SYNTAX: $gpg_options
	LANG=C gpg --no-permission-warning --homedir "$tool"/var/pub/openpgp "$@"
 }
rule_gpg_gen_key () { # SYNTAX: $uid  ENV: $gpg_options
	local uid="$1"
	install -d -m 700 \
	 var/pub/openpgp
	install -d -m 700 \
	 var/sec \
	 var/sec/openpgp
	if test ! -e "$tool"/var/sec/openpgp/"$uid".pass.gpg
	 then gpg --encrypt $gpg_options -o "$tool"/var/sec/openpgp/"$uid".pass.gpg <<-EOF
			$(stdbuf --output 0 tr -d -c '[:alnum:][:punct:]' <"${random:-/dev/urandom}" | head -c 42)
			EOF
	 fi
	if ! rule gpg --list-keys -- "$uid" >/dev/null
	 then
		rule gpg --batch --gen-key
			# DOC: http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=blob_plain;f=doc/DETAILS;hb=refs/heads/STABLE-BRANCH-1-4
			Key-Type: RSA
			Key-Length: 4096
			Key-Usage: sign
			Passphrase:$(gpg --decrypt ${gpg_options-} "$tool"/var/sec/openpgp/"$uid".pass.gpg)
			Preferences: TWOFISH AES256 CAST5 BLOWFISH CAMELLIA256 3DES SHA512 SHA384 SHA256 SHA224 SHA1 BZIP2 ZLIB ZIP NONE MDC NO-KS-MODIFY
			$(cat -)
			%commit
			EOF
	 fi
	caps=$(
		rule gpg --with-colons --fixed-list-mode --with-fingerprint --list-secret-keys \
		 -- "$uid" |
		sed -e 's/^ssb\(:[^:]*\)\{11\}.*/\1/;t;d'
	 )
	for cap in ${subkey_caps:-}
	 do
		test ! "$caps" = "$(printf %s "$caps" | sed -e 's/'"$cap"'//g')" ||
		printf '%s\n' 8 s e $cap q 4096 ${expire:-0} save |
		rule gpg --keyid-format "long" --with-colons --fixed-list-mode --expert \
		 --passphrase-fd 3 --command-fd 0 --edit-key "$uid" addkey 3<<-EOF
			$(gpg --decrypt ${gpg_options-} "$tool"/var/sec/openpgp/"$uid".pass.gpg)
			EOF
	 done
 }
rule_mysql_backup () {
	mkdir -p "$tool"/var/backup/mysql
	rule ssh -l backup '
		for db in $(sudo -u backup mysql -u backup --skip-column-names <<-EOF
			SELECT schema_name
				FROM information_schema.schemata
				WHERE schema_name NOT IN ("information_schema", "performance_schema");
			EOF
		 ); do
			$db
		 done
	 '
 }

rule=${1:-help}
${1+shift}
case $rule in
 (help);;
 (*)
	assert 'test ! "$(hostname --fqdn)" = "$vm_fqdn"' vm_fqdn
	assert 'test ! "$(hostname --fqdn)" = "$vm_host"' vm_host
	;;
 esac
rule $rule "$@"