#!/usr/bin/env bash
# Copyright 2020 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
set -o errexit
set -o nounset
set -o pipefail
run_exec_credentials_tests() {
run_exec_credentials_tests_version client.authentication.k8s.io/v1beta1
run_exec_credentials_tests_version client.authentication.k8s.io/v1
}
run_exec_credentials_tests_version() {
set -o nounset
set -o errexit
local -r apiVersion="$1"
kube::log::status "Testing kubectl with configured ${apiVersion} exec credentials plugin"
cat > "${TMPDIR:-/tmp}"/invalid_exec_plugin.yaml << EOF
apiVersion: v1
clusters:
- cluster:
name: test
contexts:
- context:
cluster: test
user: invalid_token_user
name: test
current-context: test
kind: Config
preferences: {}
users:
- name: invalid_token_user
user:
exec:
apiVersion: ${apiVersion}
# Any invalid exec credential plugin will do to demonstrate
command: ls
interactiveMode: IfAvailable
EOF
### Provided --token should take precedence, thus not triggering the (invalid) exec credential plugin
# Pre-condition: Client certificate authentication enabled on the API server
kube::util::test_client_certificate_authentication_enabled
# Command
output=$(kubectl "${kube_flags_with_token[@]:?}" --kubeconfig="${TMPDIR:-/tmp}"/invalid_exec_plugin.yaml get namespace kube-system -o name || true)
if [[ "${output}" == "namespace/kube-system" ]]; then
kube::log::status "exec credential plugin not triggered since kubectl was called with provided --token"
else
kube::log::status "Unexpected output when providing --token for authentication - exec credential plugin likely triggered. Output: ${output}"
exit 1
fi
# Post-condition: None
### Without provided --token, the exec credential plugin should be triggered
# Pre-condition: Client certificate authentication enabled on the API server - already checked by positive test above
# Command
output2=$(kubectl "${kube_flags_without_token[@]:?}" --kubeconfig="${TMPDIR:-/tmp}"/invalid_exec_plugin.yaml get namespace kube-system -o name 2>&1 || true)
if [[ "${output2}" =~ "json parse error" ]]; then
kube::log::status "exec credential plugin triggered since kubectl was called without provided --token"
else
kube::log::status "Unexpected output when not providing --token for authentication - exec credential plugin not triggered. Output: ${output2}"
exit 1
fi
# Post-condition: None
cat >"${TMPDIR:-/tmp}"/valid_exec_plugin.yaml <<EOF
apiVersion: v1
clusters:
- cluster:
name: test
contexts:
- context:
cluster: test
user: valid_token_user
name: test
current-context: test
kind: Config
preferences: {}
users:
- name: valid_token_user
user:
exec:
apiVersion: ${apiVersion}
command: echo
args:
- '{"apiVersion":"${apiVersion}","status":{"token":"admin-token"}}'
interactiveMode: IfAvailable
EOF
### Valid exec plugin should authenticate user properly
# Pre-condition: Client certificate authentication enabled on the API server - already checked by positive test above
# Command
output3=$(kubectl "${kube_flags_without_token[@]:?}" --kubeconfig="${TMPDIR:-/tmp}"/valid_exec_plugin.yaml get namespace kube-system -o name 2>&1 || true)
if [[ "${output3}" == "namespace/kube-system" ]]; then
kube::log::status "exec credential plugin triggered and provided valid credentials"
else
kube::log::status "Unexpected output when using valid exec credential plugin for authentication. Output: ${output3}"
exit 1
fi
# Post-condition: None
### Provided --username/--password should take precedence, thus not triggering the (valid) exec credential plugin
# Pre-condition: Client certificate authentication enabled on the API server - already checked by positive test above
# Command
output4=$(kubectl "${kube_flags_without_token[@]:?}" --username bad --password wrong --kubeconfig="${TMPDIR:-/tmp}"/valid_exec_plugin.yaml get namespace kube-system -o name 2>&1 || true)
if [[ "${output4}" =~ "Unauthorized" ]]; then
kube::log::status "exec credential plugin not triggered since kubectl was called with provided --username/--password"
else
kube::log::status "Unexpected output when providing --username/--password for authentication - exec credential plugin likely triggered. Output: ${output4}"
exit 1
fi
# Post-condition: None
### Provided --client-certificate/--client-key should take precedence on the cli, thus not triggering the (invalid) exec credential plugin
# contained in the kubeconfig.
# Use CSR to get a valid certificate
cat <<EOF | kubectl create -f -
apiVersion: certificates.k8s.io/v1
kind: CertificateSigningRequest
metadata:
name: testuser
spec:
request: $(base64 < hack/testdata/auth/testuser.csr | tr -d '\n')
signerName: kubernetes.io/kube-apiserver-client
usages: [client auth]
EOF
kube::test::wait_object_assert 'csr/testuser' '{{range.status.conditions}}{{.type}}{{end}}' ''
kubectl certificate approve testuser
kube::test::wait_object_assert 'csr/testuser' '{{range.status.conditions}}{{.type}}{{end}}' 'Approved'
# wait for certificate to not be empty
kube::test::wait_object_assert 'csr/testuser' '{{.status.certificate}}' '.+'
kubectl get csr testuser -o jsonpath='{.status.certificate}' | base64 -d > "${TMPDIR:-/tmp}"/testuser.crt
output5=$(kubectl "${kube_flags_without_token[@]:?}" --client-certificate="${TMPDIR:-/tmp}"/testuser.crt --client-key="hack/testdata/auth/testuser.key" --kubeconfig="${TMPDIR:-/tmp}"/invalid_exec_plugin.yaml get namespace kube-system -o name)
if [[ "${output5}" =~ "Unauthorized" ]]; then
kube::log::status "Unexpected output when providing --client-certificate/--client-key for authentication - exec credential plugin likely triggered. Output: ${output5}"
exit 1
else
kube::log::status "exec credential plugin not triggered since kubectl was called with provided --client-certificate/--client-key"
fi
### Provided --client-certificate/--client-key should take precedence in the kubeconfig, thus not triggering the (invalid) exec credential plugin.
cat >"${TMPDIR:-/tmp}"/invalid_execcredential.sh <<EOF
#!/bin/bash
echo '{"kind":"ExecCredential","apiVersion":"client.authentication.k8s.io/v1beta1","status":{"clientKeyData":"bad","clientCertificateData":"bad"}}'
EOF
chmod +x "${TMPDIR:-/tmp}"/invalid_execcredential.sh
kubectl config set-credentials testuser --client-certificate="${TMPDIR:-/tmp}"/testuser.crt --client-key="hack/testdata/auth/testuser.key" --exec-api-version=client.authentication.k8s.io/v1beta1 --exec-command=/tmp/invalid_execcredential.sh
output6=$(kubectl "${kube_flags_without_token[@]:?}" --user testuser get namespace kube-system -o name)
if [[ "${output6}" =~ "Unauthorized" ]]; then
kube::log::status "Unexpected output when kubeconfig was configured with --client-certificate/--client-key for authentication - exec credential plugin likely triggered. Output: ${output6}"
exit 1
else
kube::log::status "exec credential plugin not triggered since kubeconfig was configured with --client-certificate/--client-key for authentication"
fi
kubectl delete csr testuser
rm "${TMPDIR:-/tmp}"/invalid_execcredential.sh
rm "${TMPDIR:-/tmp}"/invalid_exec_plugin.yaml
rm "${TMPDIR:-/tmp}"/valid_exec_plugin.yaml
set +o nounset
set +o errexit
}
run_exec_credentials_interactive_tests() {
run_exec_credentials_interactive_tests_version client.authentication.k8s.io/v1beta1
run_exec_credentials_interactive_tests_version client.authentication.k8s.io/v1
}
run_exec_credentials_interactive_tests_version() {
set -o nounset
set -o errexit
local -r apiVersion="$1"
kube::log::status "Testing kubectl with configured ${apiVersion} interactive exec credentials plugin"
cat >"${TMPDIR:-/tmp}"/always_interactive_exec_plugin.yaml <<EOF
apiVersion: v1
clusters:
- cluster:
name: test
contexts:
- context:
cluster: test
user: always_interactive_token_user
name: test
current-context: test
kind: Config
preferences: {}
users:
- name: always_interactive_token_user
user:
exec:
apiVersion: ${apiVersion}
command: echo
args:
- '{"apiVersion":"${apiVersion}","status":{"token":"admin-token"}}'
interactiveMode: Always
EOF
### The exec credential plugin should not be run if it kubectl already uses standard input
# Pre-condition: The kubectl command requires standard input
some_resource='{"apiVersion":"v1","kind":"ConfigMap","metadata":{"name":"some-resource"}}'
# Declare map from kubectl command to standard input data
declare -A kubectl_commands
kubectl_commands["apply -f -"]="$some_resource"
kubectl_commands["set env deployment/some-deployment -"]="SOME_ENV_VAR_KEY=SOME_ENV_VAR_VAL"
kubectl_commands["replace -f - --force"]="$some_resource"
failure=
for kubectl_command in "${!kubectl_commands[@]}"; do
# Use a separate bash script for the command here so that script(1) will not get confused with kubectl flags
script_file="${TMPDIR:-/tmp}/test-cmd-exec-credentials-script-file.sh"
cat <<EOF >"$script_file"
#!/usr/bin/env bash
set -o errexit
set -o nounset
set -o pipefail
kubectl ${kube_flags_without_token[*]:?} --kubeconfig=${TMPDIR:-/tmp}/always_interactive_exec_plugin.yaml ${kubectl_command} 2>&1 || true
EOF
chmod +x "$script_file"
# Run kubectl as child of script(1) so kubectl will always run with a PTY
# Dynamically build script(1) command so that we can conditionally add flags on Linux
script_command="script -q /dev/null"
if [[ "$(uname)" == "Linux" ]]; then script_command="${script_command} -c"; fi
script_command="${script_command} ${script_file}"
# Specify SHELL env var when we call script(1) since it is picky about the format of the env var
shell="$(which bash)"
kube::log::status "Running command '$script_command' (kubectl command: '$kubectl_command') with input '${kubectl_commands[$kubectl_command]}'"
output=$(echo "${kubectl_commands[$kubectl_command]}" | SHELL="$shell" $script_command)
if [[ "${output}" =~ "used by stdin resource manifest reader" ]]; then
kube::log::status "exec credential plugin not run because kubectl already uses standard input"
else
kube::log::status "Unexpected output when running kubectl command that uses standard input. Output: ${output}"
failure=yup
fi
done
if [[ -n "$failure" ]]; then
exit 1
fi
# Post-condition: None
cat >"${TMPDIR:-/tmp}"/missing_interactive_exec_plugin.yaml <<EOF
apiVersion: v1
clusters:
- cluster:
name: test
contexts:
- context:
cluster: test
user: missing_interactive_token_user
name: test
current-context: test
kind: Config
preferences: {}
users:
- name: missing_interactive_token_user
user:
exec:
apiVersion: ${apiVersion}
command: echo
args:
- '{"apiVersion":"${apiVersion}","status":{"token":"admin-token"}}'
EOF
### The kubeconfig will fail to be loaded if a v1 exec credential plugin is missing an interactiveMode field, otherwise it will default to IfAvailable
# Pre-condition: The exec credential plugin is missing an interactiveMode setting
output2=$(kubectl "${kube_flags_without_token[@]:?}" --kubeconfig="${TMPDIR:-/tmp}"/missing_interactive_exec_plugin.yaml get namespace kube-system -o name 2>&1 || true)
if [[ "$apiVersion" == "client.authentication.k8s.io/v1" ]]; then
if [[ "${output2}" =~ "error: interactiveMode must be specified for missing_interactive_token_user to use exec authentication plugin" ]]; then
kube::log::status "kubeconfig was not loaded successfully because ${apiVersion} exec credential plugin is missing interactiveMode"
else
kube::log::status "Unexpected output when running kubectl command that uses a ${apiVersion} exec credential plugin without an interactiveMode. Output: ${output2}"
exit 1
fi
else
if [[ "${output2}" == "namespace/kube-system" ]]; then
kube::log::status "${apiVersion} exec credential plugin triggered and provided valid credentials"
else
kube::log::status "Unexpected output when using valid exec credential plugin for authentication. Output: ${output2}"
exit 1
fi
fi
# Post-condition: None
rm "${TMPDIR:-/tmp}"/always_interactive_exec_plugin.yaml
rm "${TMPDIR:-/tmp}"/missing_interactive_exec_plugin.yaml
set +o nounset
set +o errexit
}
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