1 files changed, 31 insertions, 0 deletions
diff --git a/selftest/ns/mk_nsenter.sh b/selftest/ns/mk_nsenter.sh
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--- /dev/null
+++ b/selftest/ns/mk_nsenter.sh
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+#!/bin/sh
+#
+# Helper script. If you want a 2nd shell that communicates with the testenv DC
+# you can use the nsenter command to change the namespace you're in. However,
+# this command is a bit unwieldy and changes depending on the testenv PID.
+# We can generate a helper script on the fly that abstracts all this
+# complexity, allowing you to use the same, simple command to change the
+# namespace that you're in, e.g.
+#   st/ad_dc/nsenter.sh
+
+pid=$1
+exports_file=$2
+
+# The basic command to enter the testenv's network namespace.
+# We enter the user namespace as well (as ourself, which is really the root
+# user for the namespace), otherwise we need sudo to make this work.
+nsenter_cmd="nsenter -t $pid --net --user --preserve-credentials"
+
+# By default, the nsenter command will just start a new shell in the namespace.
+# we use a wrapper helper script, which first loads all the environment
+# variables that are usually defined in selftest (and prints some basic help).
+helper_script="$(dirname $0)/nsenter-helper.sh $exports_file"
+
+# generate the dynamic script
+dyn_script="$(dirname $2)/nsenter.sh"
+echo "#!/bin/sh" >$dyn_script
+echo "$nsenter_cmd $helper_script" >>$dyn_script
+chmod 755 $dyn_script
+
+# return the script we created
+echo "$dyn_script"