compat API: respect base_hosts_file containers.conf option

Hard coding to none without checking containers.conf is not a good idea
as users who liked the previous behavior and the podman default behavior
of keeping the hosts entries can no longer do that.

With this commit they can set base_hosts_file = "/etc/hosts" to restore
the previous behavior.

Fixes: https://issues.redhat.com/browse/RHEL-92995

Signed-off-by: Paul Holzinger <[email protected]>

Author: Luap99

pkg/api/handlers/compat/containers_create.go

@@ -120,8 +120,10 @@ func CreateContainer(w http.ResponseWriter, r *http.Request) {
 	// moby always create the working directory
 	localTrue := true
 	sg.CreateWorkingDir = &localTrue
-	// moby doesn't inherit /etc/hosts from host
-	sg.BaseHostsFile = "none"
+	// moby doesn't inherit /etc/hosts from host, but only overwrite if not set in containers.conf
+	if rtc.Containers.BaseHostsFile == "" {
+		sg.BaseHostsFile = "none"
+	}
 
 	ic := abi.ContainerEngine{Libpod: runtime}
 	report, err := ic.ContainerCreate(r.Context(), sg)

test/apiv2/20-containers.at

@@ -677,6 +677,35 @@ for endpoint in containers/create libpod/containers/create; do
 done
 
 stop_service
+# Create a temporary containers.conf with custom base_hosts_file set
+testdir=$(mktemp -d)
+cat > $testdir/containers.base_hosts_file.conf <<EOF
+[containers]
+base_hosts_file = "$testdir/hosts"
+EOF
+
+cat > $testdir/hosts <<EOF
+10.0.0.2 testname
+192.168.1.1 abc
+EOF
+
+CONTAINERS_CONF_OVERRIDE=$testdir/containers.base_hosts_file.conf start_service
+
+t POST containers/create \
+  Image=$IMAGE \
+  Cmd='["cat","/etc/hosts"]' \
+  Tty=true \
+  201 \
+  .Id~[0-9a-f]\\{64\\}
+cid=$(jq -r '.Id' <<<"$output")
+
+t POST  containers/${cid}/start 204
+
+t GET "containers/${cid}/logs?follow=true&stdout=true&stderr=true" 200
+like "$(<$WORKDIR/curl.result.out)" ".*10.0.0.2[[:space:]]testname.*192.168.1.1[[:space:]]abc.*" "contains containers.conf base_hosts_file hosts"
+
+stop_service
+rm -rf "$testdir"
 start_service
 
 # Our states are different from Docker's.