# Cases for ../host-modules/lib/attic-root-facts.nix. Each case runs the script
# against a stub `bao` over a store kept in files, and compares what the script
# left in its directory and which leaves it read.
set -uo pipefail

failures=0
count=0
case="setup"

fail() {
  echo "FAILED: $case: $*" >&2
  failures=$((failures + 1))
}

expect() { # <description> <got> <want>
  count=$((count + 1))
  if [ "$2" != "$3" ]; then fail "$1: got '$2', wanted '$3'"; fi
}

dir=$(mktemp -d)
mkdir -p "$dir/bin"
sed -e "s|@DIR@|$dir|g" "$SCRIPT" >"$dir/script.sh"
calls=$dir/calls
export DIR=$dir

# `login` answers from LOGIN_FAIL. `kv get -field=value <path>` prints the file
# kept for the path; a missing one is the store's "no value found" and DENY_READ
# is a policy that grants nothing. Every call is logged.
cat >"$dir/bin/bao" <<STUB
#!$BASH
echo "bao \$*" >>"$calls"
case "\$1 \$2" in
  "login -method=cert")
    if [ "\${LOGIN_FAIL:-0}" = 1 ]; then echo "certificate refused" >&2; exit 2; fi
    echo store-token
    ;;
  "kv get")
    [ "\${BAO_TOKEN-}" = store-token ] || { echo "kv without the login's token" >&2; exit 97; }
    f="\$DIR/store/\$(printf '%s' "\$4" | tr / _)"
    if [ "\${DENY_READ:-0}" = 1 ]; then echo "permission denied" >&2; exit 2; fi
    [ -f "\$f" ] || { echo "No value found at \$4" >&2; exit 2; }
    cat "\$f"
    ;;
  *) echo "unexpected call: \$*" >&2; exit 98 ;;
esac
STUB
chmod +x "$dir/bin/bao"

# `systemctl` answers for nix-daemon.service: DAEMON_STARTED is when it last
# became active (empty: never, so it is not running) and every call is logged.
cat >"$dir/bin/systemctl" <<STUB
#!$BASH
echo "systemctl \$*" >>"$dir/systemctl"
case "\$1" in
  show) printf '%s\n' "\${DAEMON_STARTED-}" ;;
  is-failed) exit 1 ;;
  is-active) [ -n "\${DAEMON_STARTED-}" ] ;;
  try-restart) ;;
  *) echo "unexpected call: \$*" >&2; exit 98 ;;
esac
STUB
chmod +x "$dir/bin/systemctl"
export PATH="$dir/bin:$PATH"

# Certificates made here, with fixed names and subjects: `system-ca` stands for
# a CA the host's own bundle holds, `swarm-ca` for the swarm's root, `host-ca`
# for a bundle the host's nix.conf names. `swarm-leaf` and `system-leaf` are
# servers for localhost signed by the first two.
pki=$dir/pki
mkdir -p "$pki"
newca() { # <name>
  openssl req -x509 -newkey ec -pkeyopt ec_paramgen_curve:prime256v1 -nodes \
    -keyout "$pki/$1.key" -out "$pki/$1.pem" -subj "/CN=$1" -days 2 \
    -addext basicConstraints=critical,CA:TRUE -addext keyUsage=keyCertSign 2>/dev/null
}
newleaf() { # <ca> <name>
  openssl req -newkey ec -pkeyopt ec_paramgen_curve:prime256v1 -nodes \
    -keyout "$pki/$2.key" -out "$pki/$2.csr" -subj "/CN=localhost" 2>/dev/null
  printf 'subjectAltName=DNS:localhost\nbasicConstraints=CA:FALSE\n' >"$pki/$2.ext"
  openssl x509 -req -in "$pki/$2.csr" -CA "$pki/$1.pem" -CAkey "$pki/$1.key" \
    -CAcreateserial -out "$pki/$2.pem" -days 2 -extfile "$pki/$2.ext" 2>/dev/null
}
newca system-ca
newca swarm-ca
newca host-ca
newleaf swarm-ca swarm-leaf
newleaf system-ca system-leaf
certs() { grep -c -- '-----BEGIN CERTIFICATE-----' "$1" 2>/dev/null || echo 0; }

KEYLEAF=secret_swarm_hives_alpha_attic_public-key
TOKENLEAF=secret_swarm_hives_alpha_attic_pull-token

reset() {
  rm -rf "$dir/store" "$dir/attic" "$dir/nix" "$dir/host-netrc" "$calls" "$dir/systemctl"
  cp "$pki/system-ca.pem" "$dir/system-bundle.crt"
  cp "$pki/swarm-ca.pem" "$dir/swarm-root.pem"
  cp "$pki/host-ca.pem" "$dir/host-ca.pem"
  mkdir -p "$dir/store"
  : >"$calls"
  : >"$dir/systemctl"
}

seed() { # <key> <token>
  printf '%s' "$1" >"$dir/store/$KEYLEAF"
  printf '%s' "$2" >"$dir/store/$TOKENLEAF"
}

# run [VAR=value…]: the script's exit status.
run() {
  env "$@" bash "$dir/script.sh" >"$dir/out" 2>"$dir/err"
}

restarts() { grep -c '^systemctl try-restart' "$dir/systemctl"; }
mode() { stat -c %a "$1" 2>/dev/null || echo missing; }
ino() { stat -c %i "$1" 2>/dev/null || echo missing; }
body() { cat "$1" 2>/dev/null || echo missing; }

case="first run writes the key (0600, in a 0700 directory) and the netrc (0600)"
reset
seed "swarm:S0VZ" "tok-1"
run
expect "exit" $? 0
expect "key" "$(body "$dir/attic/public-key")" "swarm:S0VZ"
expect "netrc" "$(body "$dir/nix/netrc")" "machine cache.example password tok-1"
expect "key mode" "$(mode "$dir/attic/public-key")" 600
expect "netrc mode" "$(mode "$dir/nix/netrc")" 600
expect "dir mode" "$(mode "$dir/attic")" 700
expect "fragment names the cache, the key, the root-only netrc and the CA bundle" "$(body "$dir/nix/cache.conf")" "extra-substituters = https://cache.example/swarm
extra-trusted-public-keys = swarm:S0VZ
netrc-file = $dir/nix/netrc
ssl-cert-file = $dir/nix/ca-bundle.crt"
expect "fragment mode" "$(mode "$dir/nix/cache.conf")" 644
expect "fragment dir mode" "$(mode "$dir/nix")" 755
expect "no secret in the fragment" "$(grep -c tok-1 "$dir/nix/cache.conf")" 0
expect "control: the token is in the netrc" "$(grep -c tok-1 "$dir/nix/netrc")" 1
expect "the netrc the fragment names is root-only" "$(mode "$dir/nix/netrc")" 600

case="a second run with the same facts rewrites nothing"
k=$(ino "$dir/attic/public-key")
n=$(ino "$dir/nix/netrc")
c=$(ino "$dir/nix/cache.conf")
run
expect "exit" $? 0
expect "key untouched" "$(ino "$dir/attic/public-key")" "$k"
expect "netrc untouched" "$(ino "$dir/nix/netrc")" "$n"
expect "fragment untouched" "$(ino "$dir/nix/cache.conf")" "$c"

case="a rotated token replaces the netrc and leaves the key"
seed "swarm:S0VZ" "tok-2"
run
expect "exit" $? 0
expect "netrc" "$(body "$dir/nix/netrc")" "machine cache.example password tok-2"
expect "netrc mode" "$(mode "$dir/nix/netrc")" 600
expect "key untouched" "$(ino "$dir/attic/public-key")" "$k"

case="a rotated key replaces the key file"
seed "swarm:Tk9XCg" "tok-2"
run
expect "exit" $? 0
expect "key" "$(body "$dir/attic/public-key")" "swarm:Tk9XCg"

case="only the hive's own leaves are read, after a login"
expect "reads" "$(grep -c '^bao kv get' "$calls")" "$(grep -c '^bao kv get -field=value secret/swarm/hives/alpha/attic/' "$calls")"
expect "login first" "$(head -1 "$calls")" "bao login -method=cert -token-only"
expect "something was read" "$([ "$(grep -c '^bao kv get' "$calls")" -ge 2 ] && echo yes || echo no)" yes

# The merged netrc: the cache's entry first, then the host's other entries as
# they are. A missing host file is no entries.
HOSTNETRC='machine git.example login bob password hunter2
machine other.example
  login alice
  password s3cret'

case="a host netrc with two other machines keeps both, after the cache's entry"
reset
seed "swarm:S0VZ" "tok-1"
printf '%s\n' "$HOSTNETRC" >"$dir/host-netrc"
run
expect "exit" $? 0
expect "merged" "$(body "$dir/nix/netrc")" "machine cache.example password tok-1
$HOSTNETRC"
expect "mode" "$(mode "$dir/nix/netrc")" 600
expect "the host's file is not written" "$(body "$dir/host-netrc")" "$HOSTNETRC"

case="a host entry for the cache's own machine is replaced and the rest is kept"
reset
seed "swarm:S0VZ" "tok-1"
printf '%s\n%s\n' "$HOSTNETRC" "machine cache.example login old password stale" >"$dir/host-netrc"
run
expect "exit" $? 0
expect "merged" "$(body "$dir/nix/netrc")" "machine cache.example password tok-1
$HOSTNETRC"
expect "control: the stale entry was in the host file" "$(grep -c stale "$dir/host-netrc")" 1

case="a multi-line host entry for the cache's machine goes whole"
reset
seed "swarm:S0VZ" "tok-1"
printf '%s\n%s\n' "machine cache.example
  login old
  password stale" "$HOSTNETRC" >"$dir/host-netrc"
run
expect "exit" $? 0
expect "merged" "$(body "$dir/nix/netrc")" "machine cache.example password tok-1
$HOSTNETRC"

case="an edit to the host netrc reaches the merged file on the next run"
reset
seed "swarm:S0VZ" "tok-1"
printf '%s\n' "$HOSTNETRC" >"$dir/host-netrc"
run
printf '%s\n' "machine new.example login n password p" >>"$dir/host-netrc"
run
expect "exit" $? 0
expect "new entry merged" "$(grep -c new.example "$dir/nix/netrc")" 1
expect "old entries kept" "$(grep -c git.example "$dir/nix/netrc")" 1

case="a netrc left 0640 by an earlier deploy is rewritten 0600 though its content is current"
reset
seed "swarm:S0VZ" "tok-1"
run
chmod 640 "$dir/nix/netrc"
run
expect "exit" $? 0
expect "mode" "$(mode "$dir/nix/netrc")" 600

case="a store with no facts exits cleanly and creates nothing"
reset
run
expect "exit" $? 0
expect "no key" "$(body "$dir/attic/public-key")" missing
expect "no netrc" "$(body "$dir/nix/netrc")" missing

case="one fact without the other creates nothing"
reset
printf '%s' "swarm:S0VZ" >"$dir/store/$KEYLEAF"
run
expect "exit" $? 0
expect "no key" "$(body "$dir/attic/public-key")" missing
expect "no netrc" "$(body "$dir/nix/netrc")" missing

# The failure cases start from a good state and an extra file in the directory.
good() {
  reset
  seed "swarm:S0VZ" "tok-1"
  run
  touch "$dir/attic/other"
}
intact() {
  expect "key kept" "$(body "$dir/attic/public-key")" "swarm:S0VZ"
  expect "netrc kept" "$(body "$dir/nix/netrc")" "machine cache.example password tok-1"
  expect "other file kept" "$(body "$dir/attic/other")" ""
}

case="a store that refuses the login fails the run and removes nothing"
good
seed "swarm:NEW" "tok-new"
run LOGIN_FAIL=1
expect "exit" $? 1
intact

case="a store that refuses the read fails the run and removes nothing"
good
run DENY_READ=1
expect "exit" $? 1
intact

case="a key with whitespace is refused and nothing changes"
good
seed "swarm:S0 VZ" "tok-new"
run
expect "exit" $? 1
intact

case="a token with whitespace is refused and nothing changes"
good
seed "swarm:S0VZ" "tok new"
run
expect "exit" $? 1
intact

case="a key without a name is refused and nothing changes"
good
seed "S0VZ" "tok-new"
run
expect "exit" $? 1
intact

# A restart of nix-daemon is asked for only when the fragment was written after
# the daemon last started; `now` is when the daemon "started", read between runs.
now() { date -u '+%a %Y-%m-%d %H:%M:%S.%6N UTC'; }

case="a new fragment restarts a daemon that started before it"
reset
seed "swarm:S0VZ" "tok-1"
run DAEMON_STARTED="Sat 2000-01-01 00:00:00.000000 UTC"
expect "exit" $? 0
expect "restart asked" "$(grep -c '^systemctl try-restart --no-block nix-daemon.service' "$dir/systemctl")" 1
expect "restart claimed" "$(grep -c "cache.conf changed after nix-daemon.service last started — restarting it\$" "$dir/out")" 1

case="a daemon that never ran is not restarted, and nothing claims it was"
reset
seed "swarm:S0VZ" "tok-1"
run DAEMON_STARTED=
expect "exit" $? 0
expect "fragment written" "$(grep -c "^extra-substituters" "$dir/nix/cache.conf")" 1
expect "no restart" "$(restarts)" 0
expect "no change-vs-start claim" "$(grep -c "changed after" "$dir/out")" 0

case="the same facts leave the fragment and the daemon alone"
started=$(now)
: >"$dir/systemctl"
run DAEMON_STARTED="$started"
expect "exit" $? 0
expect "no restart" "$(restarts)" 0

case="a rotated token changes the netrc but not the fragment, so no restart"
started=$(now)
seed "swarm:S0VZ" "tok-2"
run DAEMON_STARTED="$started"
expect "exit" $? 0
expect "netrc" "$(body "$dir/nix/netrc")" "machine cache.example password tok-2"
expect "no restart" "$(restarts)" 0

case="a rotated key rewrites the fragment and restarts the daemon"
started=$(now)
seed "swarm:Tk9XCg" "tok-2"
run DAEMON_STARTED="$started"
expect "exit" $? 0
expect "key in the fragment" "$(grep -c 'extra-trusted-public-keys = swarm:Tk9XCg' "$dir/nix/cache.conf")" 1
expect "restart asked" "$(restarts)" 1

case="a store with no facts writes no fragment and restarts nothing"
reset
run DAEMON_STARTED="Sat 2000-01-01 00:00:00.000000 UTC"
expect "exit" $? 0
expect "no fragment" "$(body "$dir/nix/cache.conf")" missing
expect "no restart" "$(restarts)" 0

case="a key that is refused writes no fragment"
reset
seed "swarm:S0 VZ" "tok-1"
run
expect "exit" $? 1
expect "no fragment" "$(body "$dir/nix/cache.conf")" missing

# The CA bundle the fragment names: the host's own CAs, then the swarm's root.
bundle=$dir/nix/ca-bundle.crt

case="the bundle holds the host's CAs and the swarm's root, 0644, and the fragment names it"
reset
seed "swarm:S0VZ" "tok-1"
run
expect "exit" $? 0
expect "bundle" "$(body "$bundle")" "$(cat "$pki/system-ca.pem")
$(cat "$pki/swarm-ca.pem")"
expect "two certificates" "$(certs "$bundle")" 2
expect "mode" "$(mode "$bundle")" 644
expect "fragment names it" "$(grep -c "^ssl-cert-file = $bundle\$" "$dir/nix/cache.conf")" 1
expect "control: the host's bundle held one certificate" "$(certs "$dir/system-bundle.crt")" 1
expect "the host's bundle is not written" "$(body "$dir/system-bundle.crt")" "$(cat "$pki/system-ca.pem")"

case="the swarm and host servers verify against the bundle, and the swarm one does not against the host CAs alone"
expect "swarm leaf, bundle" "$(openssl verify -CAfile "$bundle" "$pki/swarm-leaf.pem" >/dev/null 2>&1 && echo ok || echo bad)" ok
expect "system leaf, bundle" "$(openssl verify -CAfile "$bundle" "$pki/system-leaf.pem" >/dev/null 2>&1 && echo ok || echo bad)" ok
expect "control: swarm leaf, host's CAs alone" "$(openssl verify -CAfile "$dir/system-bundle.crt" "$pki/swarm-leaf.pem" >/dev/null 2>&1 && echo ok || echo bad)" bad

# curl takes the file as nix does. A TLS server for localhost with the swarm's
# leaf, on a port picked at random until one binds.
case="curl trusts the swarm's server with the bundle and refuses it with the host's CAs alone"
port=
for _ in 1 2 3 4 5 6 7 8; do
  p=$((20000 + RANDOM % 20000))
  openssl s_server -www -accept "$p" -cert "$pki/swarm-leaf.pem" -key "$pki/swarm-leaf.key" \
    >"$dir/s_server.log" 2>&1 &
  server=$!
  for _ in 1 2 3 4 5 6 7 8 9 10; do
    if curl -s --cacert "$pki/swarm-ca.pem" "https://localhost:$p/" >/dev/null 2>&1; then port=$p; break; fi
    kill -0 "$server" 2>/dev/null || break
    sleep 0.3
  done
  [ -n "$port" ] && break
  kill "$server" 2>/dev/null
done
if [ -z "$port" ]; then
  fail "no TLS server for the curl check came up: $(cat "$dir/s_server.log")"
else
  curl -s --cacert "$bundle" "https://localhost:$port/" >/dev/null 2>&1
  expect "with the bundle" $? 0
  curl -s --cacert "$dir/system-bundle.crt" "https://localhost:$port/" >/dev/null 2>&1
  expect "with the host's CAs alone" $? 60
  kill "$server" 2>/dev/null
fi

case="a second run with the same CAs rewrites nothing"
b=$(ino "$bundle")
run
expect "exit" $? 0
expect "bundle untouched" "$(ino "$bundle")" "$b"

case="a bundle left 0640 is rewritten 0644 though its content is current"
chmod 640 "$bundle"
run
expect "exit" $? 0
expect "mode" "$(mode "$bundle")" 644

case="a host that sets its own ssl-cert-file has that file merged in, not replaced"
reset
seed "swarm:S0VZ" "tok-1"
sed -e "s|@DIR@|$dir|g" "$SCRIPT_HOSTCA" >"$dir/script-hostca.sh"
cp "$dir/script.sh" "$dir/script-default.sh"
cp "$dir/script-hostca.sh" "$dir/script.sh"
run
expect "exit" $? 0
expect "the host's file and the swarm's root" "$(body "$bundle")" "$(cat "$pki/host-ca.pem")
$(cat "$pki/swarm-ca.pem")"
line=$(sed -n 2p "$pki/system-ca.pem")
expect "the default bundle's CA is not in it" "$(grep -c -x -F -- "$line" "$bundle")" 0
expect "control: the same search finds it in its own file" "$(grep -c -x -F -- "$line" "$pki/system-ca.pem")" 1
expect "the host's file is not written" "$(body "$dir/host-ca.pem")" "$(cat "$pki/host-ca.pem")"
cat "$pki/system-ca.pem" >>"$dir/host-ca.pem"
run
expect "an edit to the host's file reaches the bundle" "$(certs "$bundle")" 3
cp "$dir/script-default.sh" "$dir/script.sh"

case="a swarm root that is not on the host yet leaves the host's CAs alone, and a later run adds it"
reset
seed "swarm:S0VZ" "tok-1"
rm "$dir/swarm-root.pem"
run DAEMON_STARTED="Sat 2000-01-01 00:00:00.000000 UTC"
expect "exit" $? 0
expect "bundle" "$(body "$bundle")" "$(cat "$pki/system-ca.pem")"
expect "the fragment still names it" "$(grep -c "^ssl-cert-file = $bundle\$" "$dir/nix/cache.conf")" 1
expect "said so" "$(grep -c "swarm-root.pem is not on this host yet" "$dir/out")" 1
started=$(now)
c=$(ino "$dir/nix/cache.conf")
: >"$dir/systemctl"
cp "$pki/swarm-ca.pem" "$dir/swarm-root.pem"
run DAEMON_STARTED="$started"
expect "exit" $? 0
expect "root added" "$(certs "$bundle")" 2
expect "fragment untouched" "$(ino "$dir/nix/cache.conf")" "$c"
expect "no restart: nix reads the bundle per download" "$(restarts)" 0

case="a swarm root file holding no certificate is not appended"
reset
seed "swarm:S0VZ" "tok-1"
echo "garbage" >"$dir/swarm-root.pem"
run
expect "exit" $? 0
expect "bundle" "$(body "$bundle")" "$(cat "$pki/system-ca.pem")"

case="a host bundle that cannot be read fails the run and leaves the fragment and bundle"
good
cp "$bundle" "$dir/bundle-before"
rm "$dir/system-bundle.crt"
seed "swarm:NEW" "tok-new"
run
expect "exit" $? 1
expect "says why" "$(grep -c "cannot read the host.s CA bundle" "$dir/err")" 1
expect "bundle kept" "$(body "$bundle")" "$(body "$dir/bundle-before")"
expect "fragment kept" "$(grep -c 'extra-trusted-public-keys = swarm:S0VZ' "$dir/nix/cache.conf")" 1

if [ "$failures" -ne 0 ]; then
  echo "$failures of $count checks failed" >&2
  exit 1
fi
echo "$count checks passed"