From 9692d409658ce552ab3e0d9f41aadca1c7bcb407 Mon Sep 17 00:00:00 2001 From: Guilhem Moulin Date: Sat, 28 Jun 2014 22:37:14 +0200 Subject: Make genkeypair.sh able to display TXT record for DKIM signatures. --- roles/common/files/usr/local/bin/genkeypair.sh | 82 ++++++++++++++++++-------- 1 file changed, 56 insertions(+), 26 deletions(-) (limited to 'roles/common/files/usr/local/bin') diff --git a/roles/common/files/usr/local/bin/genkeypair.sh b/roles/common/files/usr/local/bin/genkeypair.sh index 6c75fa4..16f9658 100755 --- a/roles/common/files/usr/local/bin/genkeypair.sh +++ b/roles/common/files/usr/local/bin/genkeypair.sh @@ -1,8 +1,8 @@ #!/bin/sh -# Generate self-signed server certificates. Inspired from -# make-ssl-cert(8). -# XXX: add support for DKIM and OpenSSH +# Wrapper around openssl to generate self-signed X.509 server +# certificates or Certificate Signing Requests, or DKIM private keys. +# Inspired from make-ssl-cert(8) and opendkim-genkey(8). # # Copyright © 2014 Guilhem Moulin # @@ -28,7 +28,6 @@ bits= hash= force= -x509=-x509 config= pubkey=pubkey.pem privkey=privkey.pem @@ -36,8 +35,12 @@ dns= usage() { cat >&2 <<- EOF - Usage: $0 [OPTIONS] - Generate self-signed server certificates + Usage: $0 command [OPTIONS] + + Command: + x509: generate a self-signed X.509 server certificate + csr: generate a Certificate Signing Request + dkim: generate a DKIM private key Options: -t type: key type (default: rsa) @@ -45,7 +48,6 @@ usage() { -h digest: digest algorithm --dns CN: common name (default: \$(hostname --fqdn); can be repeated -f force: overwrite key files if they exist - --csr: generate a Certificate Signing Request instead --config: configuration file --pubkey: public key file (default: pubkey.pem) --privkey: private key file (default: privkey.pem; created with og-rwx) @@ -57,6 +59,13 @@ usage() { EOF } +[ $# -gt 0 ] || { usage; exit 2; } +cmd="$1"; shift +case "$cmd" in + x509|csr|dkim) ;; + *) echo "Unrecognized command: $cmd" >&2; exit 2 +esac + while [ $# -gt 0 ]; do case "$1" in -t) shift; type="$1";; @@ -73,7 +82,6 @@ while [ $# -gt 0 ]; do --pubkey=?*) pubkey="${1#--pubkey=}";; --privkey=?*) privkey="${1#--privkey=}";; - --csr) x509=;; --dns=?*) dns="${dns:+$dns,}${1#--dns=}";; --config=?*) dns="${1#--config=}";; @@ -98,22 +106,28 @@ case "$type" in *) echo "Unrecognized key type: $type" >&2; exit 2 esac -case "$hash" in - md5|rmd160|sha1|sha224|sha256|sha384|sha512|'') ;; - *) echo "Invalid digest algorithm: $hash" >&2; exit 2; -esac +cn= +if [ "$cmd" = x509 -o "$cmd" = csr ]; then + case "$hash" in + md5|rmd160|sha1|sha224|sha256|sha384|sha512|'') ;; + *) echo "Invalid digest algorithm: $hash" >&2; exit 2; + esac -[ "$dns" ] || dns="$(hostname --fqdn)" -cn="${dns%%,*}" -[ ${#cn} -le 64 ] || { echo "CommonName too long: $cn" >&2; exit 2; } + [ "$dns" ] || dns="$(hostname --fqdn)" + cn="${dns%%,*}" + [ ${#cn} -le 64 ] || { echo "CommonName too long: $cn" >&2; exit 2; } +fi -for file in "$pubkey" "$privkey"; do - [ -z "$force" -a -s "$file" ] || continue - echo "Error: File exists: $file" >&2 - exit 1 -done +[ -s "$privkey" -a -z "$force" ] && force=0 +if [ "$cmd" != dkim ]; then + for file in "$pubkey" "$privkey"; do + [ "$force" != 1 -a -s "$file" ] || continue + echo "Error: File exists: $file" >&2 + exit 1 + done +fi -if [ -z "$config" ]; then +if [ -z "$config" -a \( "$cmd" = x509 -o "$cmd" = csr \) ]; then config=$(mktemp) || exit 2 trap 'rm -f "$config"' EXIT @@ -144,9 +158,25 @@ if [ -z "$config" ]; then EOF fi -# Ensure "$privkey" is created with umask 0077 -mv "$(mktemp)" "$privkey" || exit 2 -chmod og-rwx "$privkey" || exit 2 +if [ "$force" != 0 ]; then + # Ensure "$privkey" is created with umask 0077 + mv "$(mktemp)" "$privkey" || exit 2 + chmod og-rwx "$privkey" || exit 2 + openssl $genkey -rand /dev/urandom $genkeyargs >"$privkey" || exit 2 +fi -openssl $genkey -rand /dev/urandom $genkeyargs >"$privkey" || exit 2 -openssl req -config "$config" -new $x509 ${hash:+-$hash} -key "$privkey" >"$pubkey" || exit 2 +if [ "$cmd" = x509 -o "$cmd" = csr ]; then + [ "$cmd" = x509 ] && x509=-x509 || x509= + openssl req -config "$config" -new $x509 ${hash:+-$hash} -key "$privkey" >"$pubkey" || exit 2 +elif [ "$cmd" = dkim ]; then + echo "Add the following TXT record to your DNS zone:" >&2 + echo "${dns:-$(date +%Y%m%d)}._domainkey\tIN\tTXT ( " + # See https://tools.ietf.org/html/rfc4871#section-3.6.1 + # t=s: the "i=" domain in signature headers MUST NOT be a subdomain of "d=" + # s=email: limit DKIM signing to email + openssl pkey -pubout <"$privkey" | sed '/^--.*--$/d' \ + | { echo -n "v=DKIM1; k=$type; t=s; s=email; p="; tr -d '\n'; } \ + | fold -w 250 \ + | { sed 's/.*/\t"&"/'; echo ' )'; } + [ "$force" != 0 ] || exit 1 +fi -- cgit v1.2.3