#!/usr/bin/env bash
# Test WolfSSL/OpenSSL srtp interoperability
#
# TODO: add OpenSSL client with WolfSSL server

set -e

if ! test -n "$WOLFSSL_OPENSSL_TEST"; then
    echo "WOLFSSL_OPENSSL_TEST NOT set, won't run"
    exit 0
fi

OPENSSL=${OPENSSL:="openssl"}
WOLFSSL_CLIENT=${WOLFSSL_CLIENT:="./examples/client/client"}

# need a unique port since may run the same time as testsuite
generate_port() {
    #-------------------------------------------------------------------------#
    # Generate a random port number
    #-------------------------------------------------------------------------#

    if [[ "$OSTYPE" == "linux"* ]]; then
        port=$(($(od -An -N2 /dev/urandom) % (65535-49512) + 49512))
    elif [[ "$OSTYPE" == "darwin"* ]]; then
        port=$(($(od -An -N2 /dev/random) % (65535-49512) + 49512))
    else
        echo "Unknown OS TYPE"
        exit 1
    fi
}

# get size of key material based on the profile
# $1 srtp profile
get_key_material_size() {
    case "$1" in
        "SRTP_AES128_CM_SHA1_80")
            ekm_size=60 ;;
        "SRTP_AES128_CM_SHA1_32")
            ekm_size=60 ;;
        "SRTP_NULL_SHA1_80")
            ekm_size=28 ;;
        "SRTP_NULL_SHA1_32")
            ekm_size=27 ;;
        "SRTP_AEAD_AES_128_GCM")
            ekm_size=56;;
        "SRTP_AEAD_AES_256_GCM")
            ekm_size=88;;
        *)
            echo "SRTP profile $1 unsupported"
            exit 1
    esac
}


# Start an OpenSSL server dtls with srtp
# $1: dtsl version [1.0, 1.2]
# $2: srtp profile string
start_openssl_server() {
    generate_port
    server_port=$port
    srtp_profile=$2

    if [ "$1" = "1.0" ]; then
        dtls_version=dtls1
    elif [ "$1" = "1.2" ]; then
        dtls_version=dtls1_2
    fi

    get_key_material_size "$srtp_profile"

    server_output_file=/tmp/openssl_srtp_out

    # hackish but OpenSSL doesn't work if input is fed before handshaking and
    # the wolfSSL client needs a reply to stop
    (sleep 1;echo -n "I hear you fa shizzle...") | \
        ${OPENSSL} s_server \
                   -${dtls_version} \
                   -port ${server_port} \
                   -debug \
                   -use_srtp ${srtp_profile} \
                   -keymatexport EXTRACTOR-dtls_srtp \
                   -keymatexportlen $ekm_size \
                   -cert ./certs/server-cert.pem \
                   -key ./certs/server-key.pem >$server_output_file &

    # make sure the server is up
    sleep 0.1
}

# Start an wolfssl client dtls with srtp
# $1: dtsl version [1.0, 1.2]
# $2: srtp profile string
start_wolfssl_client() {
    srtp_profile=$2

    if [ "$1" = "1.0" ]; then
        dtls_version=2
    elif [ "$1" = "1.2" ]; then
        dtls_version=3
    fi

    client_output_file=/tmp/wolfssl_srtp_out
    ${WOLFSSL_CLIENT} -u\
                      -x \
                      -v${dtls_version} \
                      --srtp ${srtp_profile} \
                      -p${server_port} >$client_output_file
}

# $1 openssl file
# $2 wolfssl file
check_ekm() {
    openssl_ekm=$(cat "$1" | grep "Keying material: " | cut -d ':' -f 2)
    echo "OPENSSL EKM: $openssl_ekm"
    wolfssl_ekm=$(cat "$2" | grep "DTLS SRTP: Exported key material: " | cut -d ':' -f 3)
    echo "WOLFSSL EKM: $wolfssl_ekm"

    if [ "$openssl_ekm" = "$wolfssl_ekm" ];then
        check_ret=0
    else
        check_ret=1
    fi
}

# $1 dtsl version
# $2 srtp profile
check_dtls_srtp() {
    start_openssl_server $1 $2
    start_wolfssl_client $1 $2
    check_ekm $server_output_file $client_output_file
    echo -n "check dtls $1 $2... "
    if [ $check_ret -ne 0 ];then
        echo "failed"
        exit 1
    else
        echo "ok"
    fi
}

# SRTP_NULL_SHA1_80" and SRTP_NULL_SHA1_32 aren't supported by OpenSSL
PROFILES="SRTP_AES128_CM_SHA1_80 \
        SRTP_AES128_CM_SHA1_32 \
        SRTP_AEAD_AES_128_GCM \
        SRTP_AEAD_AES_256_GCM"

for DTLS in 1.0 1.2;do
    for SRTP_PROF in $PROFILES;do
        check_dtls_srtp $DTLS $SRTP_PROF
    done
done