Trust ca cert on Linux based on hostname and port

trust-ca-cert.sh

#!/bin/sh

FULL_HOST=$1

if [ -z "$FULL_HOST" ]; then
    FULL_HOST=localhost:443
fi

HOST=$(echo $FULL_HOST | cut -d ':' -f 1)
PORT=$(echo $FULL_HOST | cut -d ':' -f 2)

if [ "$HOST" = "$PORT" ]; then
    PORT=443
fi

mkdir /tmp/trusting-ca && openssl s_client -showcerts \
  -connect $HOST:$PORT -servername $HOST < /dev/null \
  | awk '/BEGIN/,/END/{ if(/BEGIN/){i++}; out="/tmp/trusting-ca/"i".crt"; print >out}' \
  && mv /tmp/trusting-ca/$(ls /tmp/trusting-ca/ -1 | tail -1) /usr/local/share/ca-certificates/$HOST-ca.crt \
  && rm -rf /tmp/trusting-ca

update-ca-certificates

Usage:

trust-ca-cert.sh <hostname>[:<port>]