From 265f133600e9812726a52ea3067409ed3578e882 Mon Sep 17 00:00:00 2001 From: Guilhem Moulin Date: Thu, 10 Dec 2020 19:39:10 +0100 Subject: libinterimap: make SSL_verify check the hostname as well. More precisely, ensure that the certificate Subject Alternative Name (SAN) or Subject CommonName (CN) matches the hostname or IP literal specified by the 'host' option. Previously it was only verifying the chain of trust. This bumps the minimum Net::SSLeay version to 1.83 and OpenSSL version 1.0.2. --- tests/tls-verify-peer/interimap.remote | 1 - tests/tls-verify-peer/t | 61 ++++++++++++++++++++++++++++++---- 2 files changed, 54 insertions(+), 8 deletions(-) (limited to 'tests/tls-verify-peer') diff --git a/tests/tls-verify-peer/interimap.remote b/tests/tls-verify-peer/interimap.remote index b02fcd0..263655f 100644 --- a/tests/tls-verify-peer/interimap.remote +++ b/tests/tls-verify-peer/interimap.remote @@ -1,2 +1 @@ -host = ::1 port = 10993 diff --git a/tests/tls-verify-peer/t b/tests/tls-verify-peer/t index 9b676a6..2461a1f 100644 --- a/tests/tls-verify-peer/t +++ b/tests/tls-verify-peer/t @@ -1,6 +1,15 @@ +X509_SHA256="$(doveconf -c "$HOME_remote/.dovecot/config" -hx ssl_cert \ + | openssl x509 -noout -fingerprint -sha256 \ + | sed -rn "/^.*=\\s*/ {s///p;q}" | tr -d : | tr "[A-Z]" "[a-z]")" +PKEY_SHA256="$(doveconf -c "$HOME_remote/.dovecot/config" -hx ssl_cert \ + | openssl x509 -pubkey | openssl pkey -pubin -outform DER \ + | openssl dgst -sha256 | sed -rn "/^.*=\\s*/ {s///p;q}")" + unverified_peer() { ! interimap --debug || error + # make sure we aborted the handshake immediately after connecting + grep -Fx "remote: Peer certificate fingerprint: sha256\$$X509_SHA256" <"$STDERR" || error grep -Fx "remote: ERROR: Can't initiate TLS/SSL handshake" <"$STDERR" || error sed -nr "s/remote: \[[0-9]+\] (preverify=[0-9]+)$/\1/p" <"$STDERR" >"$TMPDIR/preverify" [ -s "$TMPDIR/preverify" ] || error @@ -11,12 +20,13 @@ unverified_peer() { } verified_peer() { local i u - for ((i = 0; i < 32; i++)); do + for ((i = 0; i < 4; i++)); do u="$(shuf -n1 -e "local" "remote")" sample_message | deliver -u "$u" done interimap --debug || error + grep -Fx "remote: Peer certificate fingerprint: sha256\$$X509_SHA256" <"$STDERR" || error sed -nr "s/remote: \[[0-9]+\] (preverify=[0-9]+)$/\1/p" <"$STDERR" >"$TMPDIR/preverify" [ -s "$TMPDIR/preverify" ] || error ! grep -Fvx "preverify=1" <"$TMPDIR/preverify" || error @@ -39,9 +49,6 @@ unverified_peer step_done step_start "peer verification result honored when pinned pubkey matches" -PKEY_SHA256="$(doveconf -c "$HOME_remote/.dovecot/config" -hx ssl_cert \ - | openssl x509 -pubkey | openssl pkey -pubin -outform DER \ - | openssl dgst -sha256 | sed -rn "/^.*=\\s*/ {s///p;q}")" with_remote_config <<-EOF SSL_fingerprint = sha256\$$PKEY_SHA256 EOF @@ -50,31 +57,71 @@ grep -Fx "remote: Peer certificate matches pinned SPKI digest sha256\$$PKEY_SHA2 step_done capath=$(mktemp --tmpdir="$TMPDIR" --directory capath.XXXXXX) +cp -T -- ~/.dovecot/conf.d/ca.crt "$capath/ca-certificates.crt" step_start "SSL_CAfile" if [ -f "/etc/ssl/certs/ca-certificates.crt" ]; then - # our fake root CA should not be in there + # assume our fake root CA is not there with_remote_config <<<"SSL_CAfile = /etc/ssl/certs/ca-certificates.crt" unverified_peer fi -cp -T -- ~/.dovecot/conf.d/ca.crt "$capath/ca-certificates.crt" +# default host (localhost) is the CN (and also subjectAltName) with_remote_config <<<"SSL_CAfile = $capath/ca-certificates.crt" verified_peer + +# hostnames and IPs included in the subjectAltName should work as well +for host in "ip6-localhost" "127.0.0.1" "::1"; do + with_remote_config <<-EOF + host = $host + SSL_CAfile = $capath/ca-certificates.crt + EOF + verified_peer +done + +# but not for other IPs or hostnames +for host in "ip6-loopback" "127.0.1.1"; do + with_remote_config <<-EOF + host = $host + SSL_CAfile = $capath/ca-certificates.crt + EOF + unverified_peer +done + step_done step_start "SSL_CApath" if [ -d "/etc/ssl/certs" ]; then - # our fake root CA should not be in there + # assume our fake root CA is not there with_remote_config <<<"SSL_CApath = /etc/ssl/certs" unverified_peer fi c_rehash "$capath" +# default host (localhost) is the CN (and also subjectAltName) with_remote_config <<<"SSL_CApath = $capath" verified_peer + +# hostnames and IPs included in the subjectAltName should work as well +for host in "ip6-localhost" "127.0.0.1" "::1"; do + with_remote_config <<-EOF + host = $host + SSL_CApath = $capath + EOF + verified_peer +done + +# but not for other IPs or hostnames +for host in "ip6-loopback" "127.0.1.1"; do + with_remote_config <<-EOF + host = $host + SSL_CApath = $capath + EOF + unverified_peer +done + step_done # vim: set filetype=sh : -- cgit v1.2.3