ap_curl.sh

#!/usr/bin/env nix-shell
#!nix-shell -i bash -p bash curl trurl openssl jq
set -ex

# KEY_ID="https://60228.dev/users/leo#main-key"
KEY_ID="${KEY_ID:?missing KEY_ID}"

# ssh 60228.dev 'sudo -u mastodon psql -tAc "SELECT private_key FROM accounts WHERE username = '\''leo'\'' AND domain IS NULL LIMIT 1;"' > key.pem
KEY_PATH="${KEY_PATH:?missing KEY_PATH}"

DATE="$(date -Ru | sed 's/+0000/GMT/')"
HOST="$(trurl --url "${1:?missing url}" --get '{host}')"
REQUEST_TARGET="get $(trurl --url "$1" --get '{:path}')"
HEADERS="(request-target): $REQUEST_TARGET"$'\n'"host: $HOST"$'\n'"date: $DATE"

RAW_SIGNATURE="$(echo -n "$HEADERS" | openssl dgst -binary -sign "$KEY_PATH" -sha256 | openssl enc -A -base64)"
SIGNATURE='keyId="'"$KEY_ID"'",algorithm="rsa-sha256",headers="(request-target) host date",signature="'"$RAW_SIGNATURE"'"'

curl -v \
    -H 'Accept: application/ld+json; profile="https://www.w3.org/ns/activitystreams"' \
    -H "Date: $DATE" \
    -H "Host: $HOST" \
    -H "Signature: $SIGNATURE" \
    "$1" | jq .