zcash-sync/fetch-params.sh

238 lines
6.1 KiB
Bash
Executable File

#!/bin/sh
export LC_ALL=C
set -eu
uname_S=$(uname -s 2>/dev/null || echo not)
if [ "$uname_S" = "Darwin" ]; then
PARAMS_DIR="$HOME/Library/Application Support/ZcashParams"
else
PARAMS_DIR="$HOME/.zcash-params"
fi
# Commented out because these are unused; see below.
#SPROUT_PKEY_NAME='sprout-proving.key'
#SPROUT_VKEY_NAME='sprout-verifying.key'
SAPLING_SPEND_NAME='sapling-spend.params'
SAPLING_OUTPUT_NAME='sapling-output.params'
SAPLING_SPROUT_GROTH16_NAME='sprout-groth16.params'
DOWNLOAD_URL="https://download.z.cash/downloads"
IPFS_HASH="/ipfs/QmXRHVGLQBiKwvNq7c2vPxAKz1zRVmMYbmt7G5TQss7tY7"
SHA256CMD="$(command -v sha256sum || echo shasum)"
SHA256ARGS="$(command -v sha256sum >/dev/null || echo '-a 256')"
WGETCMD="$(command -v wget || echo '')"
IPFSCMD="$(command -v ipfs || echo '')"
CURLCMD="$(command -v curl || echo '')"
# fetch methods can be disabled with ZC_DISABLE_SOMETHING=1
ZC_DISABLE_WGET="${ZC_DISABLE_WGET:-}"
ZC_DISABLE_IPFS="${ZC_DISABLE_IPFS:-}"
ZC_DISABLE_CURL="${ZC_DISABLE_CURL:-}"
LOCKFILE=/tmp/fetch_params.lock
fetch_wget() {
if [ -z "$WGETCMD" ] || [ -n "$ZC_DISABLE_WGET" ]; then
return 1
fi
cat <<EOF
Retrieving (wget): $DOWNLOAD_URL/$1
EOF
wget \
--progress=dot:giga \
--output-document="$2" \
--continue \
--retry-connrefused --waitretry=3 --timeout=30 \
"$DOWNLOAD_URL/$1"
}
fetch_ipfs() {
if [ -z "$IPFSCMD" ] || [ -n "$ZC_DISABLE_IPFS" ]; then
return 1
fi
cat <<EOF
Retrieving (ipfs): $IPFS_HASH/$1
EOF
ipfs get --output "$2" "$IPFS_HASH/$1"
}
fetch_curl() {
if [ -z "$CURLCMD" ] || [ -n "$ZC_DISABLE_CURL" ]; then
return 1
fi
cat <<EOF
Retrieving (curl): $DOWNLOAD_URL/$1
EOF
curl \
--output "$2" \
-# -L -C - \
"$DOWNLOAD_URL/$1"
}
fetch_failure() {
cat >&2 <<EOF
Failed to fetch the Zcash zkSNARK parameters!
Try installing one of the following programs and make sure you're online:
* ipfs
* wget
* curl
EOF
exit 1
}
fetch_params() {
# We only set these variables inside this function,
# and unset them at the end of the function.
filename="$1"
output="$2"
dlname="${output}.dl"
expectedhash="$3"
if ! [ -f "$output" ]
then
for i in 1 2
do
for method in wget ipfs curl failure; do
if "fetch_$method" "${filename}.part.${i}" "${dlname}.part.${i}"; then
echo "Download of part ${i} successful!"
break
fi
done
done
for i in 1 2
do
if ! [ -f "${dlname}.part.${i}" ]
then
fetch_failure
fi
done
cat "${dlname}.part.1" "${dlname}.part.2" > "${dlname}"
rm "${dlname}.part.1" "${dlname}.part.2"
"$SHA256CMD" $SHA256ARGS -c <<EOF
$expectedhash $dlname
EOF
# Check the exit code of the shasum command:
CHECKSUM_RESULT=$?
if [ $CHECKSUM_RESULT -eq 0 ]; then
mv -v "$dlname" "$output"
else
echo "Failed to verify parameter checksums!" >&2
exit 1
fi
fi
unset -v filename
unset -v output
unset -v dlname
unset -v expectedhash
}
# Use flock to prevent parallel execution.
lock() {
if [ "$uname_S" = "Darwin" ]; then
if shlock -f ${LOCKFILE} -p $$; then
return 0
else
return 1
fi
else
# create lock file
eval "exec 9>$LOCKFILE"
# acquire the lock
flock -n 9 \
&& return 0 \
|| return 1
fi
}
exit_locked_error() {
echo "Only one instance of fetch-params.sh can be run at a time." >&2
exit 1
}
main() {
lock fetch-params.sh \
|| exit_locked_error
cat <<EOF
Zcash - fetch-params.sh
This script will fetch the Zcash zkSNARK parameters and verify their
integrity with sha256sum.
If they already exist locally, it will exit now and do nothing else.
EOF
# Now create PARAMS_DIR and insert a README if necessary:
if ! [ -d "$PARAMS_DIR" ]
then
mkdir -p "$PARAMS_DIR"
README_PATH="$PARAMS_DIR/README"
cat >> "$README_PATH" <<EOF
This directory stores common Zcash zkSNARK parameters. Note that it is
distinct from the daemon's -datadir argument because the parameters are
large and may be shared across multiple distinct -datadir's such as when
setting up test networks.
EOF
# This may be the first time the user's run this script, so give
# them some info, especially about bandwidth usage:
cat <<EOF
The complete parameters are currently just under 1.7GB in size, so plan
accordingly for your bandwidth constraints. If the Sprout parameters are
already present the additional Sapling parameters required are just under
800MB in size. If the files are already present and have the correct
sha256sum, no networking is used.
Creating params directory. For details about this directory, see:
$README_PATH
EOF
fi
cd "$PARAMS_DIR"
# Sprout parameters:
# Commented out because they are unneeded, but we will eventually update
# this to delete the parameters if possible.
#fetch_params "$SPROUT_PKEY_NAME" "$PARAMS_DIR/$SPROUT_PKEY_NAME" "8bc20a7f013b2b58970cddd2e7ea028975c88ae7ceb9259a5344a16bc2c0eef7"
#fetch_params "$SPROUT_VKEY_NAME" "$PARAMS_DIR/$SPROUT_VKEY_NAME" "4bd498dae0aacfd8e98dc306338d017d9c08dd0918ead18172bd0aec2fc5df82"
# Sapling parameters:
fetch_params "$SAPLING_SPEND_NAME" "$PARAMS_DIR/$SAPLING_SPEND_NAME" "8e48ffd23abb3a5fd9c5589204f32d9c31285a04b78096ba40a79b75677efc13"
fetch_params "$SAPLING_OUTPUT_NAME" "$PARAMS_DIR/$SAPLING_OUTPUT_NAME" "2f0ebbcbb9bb0bcffe95a397e7eba89c29eb4dde6191c339db88570e3f3fb0e4"
fetch_params "$SAPLING_SPROUT_GROTH16_NAME" "$PARAMS_DIR/$SAPLING_SPROUT_GROTH16_NAME" "b685d700c60328498fbde589c8c7c484c722b788b265b72af448a5bf0ee55b50"
}
if [ "x${1:-}" = 'x--testnet' ]
then
echo "NOTE: testnet now uses the mainnet parameters, so the --testnet argument"
echo "is no longer needed (ignored)"
echo ""
fi
main
rm -f $LOCKFILE
exit 0