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tomberektomberek
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Merge pull request #11075 from abathur/macos_sequoia_proto_migration_script
add UID migration script for macOS Sequoia 15
2 parents ce4e4a1 + 0fabb34 commit 6accf86

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‎scripts/bigsur-nixbld-user-migration.sh‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -2,7 +2,7 @@
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((NEW_NIX_FIRST_BUILD_UID=301))
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5-
id_available(){
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id_unavailable(){
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dscl . list /Users UniqueID | grep -E '\b'"$1"'\b' >/dev/null
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}
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@@ -15,7 +15,7 @@ change_nixbld_names_and_ids(){
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while read -r name uid; do
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echo " Checking $name (uid: $uid)"
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# iterate for a clean ID
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while id_available "$next_id"; do
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while id_unavailable "$next_id"; do
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((next_id++))
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if ((next_id >= 400)); then
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echo "We've hit UID 400 without placing all of your users :("

‎scripts/sequoia-nixbld-user-migration.sh‎

Lines changed: 163 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,163 @@
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#!/usr/bin/env bash
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set -x
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((NEW_NIX_FIRST_BUILD_UID=350))
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((TEMP_NIX_FIRST_BUILD_UID=31000))
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nix_user_n() {
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printf "_nixbld%d" "$1"
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}
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id_unavailable(){
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dscl . list /Users UniqueID | grep -E '\b'"$1"'\b' >/dev/null
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}
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any_nixbld(){
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dscl . list /Users UniqueID | grep -E '\b_nixbld' >/dev/null
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}
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re_create_nixbld_user(){
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local name uid
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name="$1"
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uid="$2"
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sudo /usr/bin/dscl . -create "/Users/$name" "UniqueID" "$uid"
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sudo /usr/bin/dscl . -create "/Users/$name" "IsHidden" "1"
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sudo /usr/bin/dscl . -create "/Users/$name" "NFSHomeDirectory" "/var/empty"
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sudo /usr/bin/dscl . -create "/Users/$name" "RealName" "Nix build user $name"
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sudo /usr/bin/dscl . -create "/Users/$name" "UserShell" "/sbin/nologin"
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sudo /usr/bin/dscl . -create "/Users/$name" "PrimaryGroupID" "30001"
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}
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hit_id_cap(){
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echo "We've hit UID 400 without placing all of your users :("
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echo "You should use the commands in this script as a starting"
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echo "point to review your UID-space and manually move the"
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echo "remaining users (or delete them, if you don't need them)."
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}
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# evacuate the role-uid space to simplify final placement logic
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temporarily_move_existing_nixbld_uids(){
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local name uid next_id user_n
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((next_id=TEMP_NIX_FIRST_BUILD_UID))
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echo ""
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echo "Step 1: move existing _nixbld users out of the destination UID range."
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while read -r name uid; do
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# iterate for a clean ID
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while id_unavailable "$next_id"; do
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((next_id++))
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# We really want to get these all placed, but I guess there's
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# some risk we iterate forever--so we'll give up after 9k uids.
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if ((next_id >= 40000)); then
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echo "We've hit UID 40000 without temporarily placing all of your users :("
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echo "You should use the commands in this script as a starting"
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echo "point to review your UID-space and manually move the"
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echo "remaining users to any open UID over 1000."
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exit 1
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fi
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done
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sudo dscl . -create "/Users/$name" UniqueID "$next_id"
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echo " Temporarily moved $name from uid $uid -> $next_id"
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done < <(dscl . list /Users UniqueID | grep _nixbld | sort -n -k2)
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}
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change_nixbld_uids(){
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local name next_id user_n
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((next_id=NEW_NIX_FIRST_BUILD_UID))
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((user_n=1))
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name="$(nix_user_n "$user_n")"
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# we know that we have *some* nixbld users, but macOS may have
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# already clobbered the first few users if this system has been
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# upgraded
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echo ""
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echo "Step 2: re-create missing early _nixbld# users."
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until dscl . read "/Users/$name" &>/dev/null; do
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# iterate for a clean ID
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while id_unavailable "$next_id"; do
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((next_id++))
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if ((next_id >= 400)); then
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hit_id_cap
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exit 1
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fi
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done
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re_create_nixbld_user "$name" "$next_id"
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echo " $name was missing; created with uid: $next_id"
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((user_n++))
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name="$(nix_user_n "$user_n")"
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done
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echo ""
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echo "Step 3: relocate remaining _nixbld# UIDs to $next_id+"
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# start at first _nixbld# not re-created above and increment
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# until _nixbld<n> doesn't exist
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while dscl . read "/Users/$name" &>/dev/null; do
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# iterate for a clean ID
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while id_unavailable "$next_id"; do
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((next_id++))
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if ((next_id >= 400)); then
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hit_id_cap
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exit 1
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fi
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done
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sudo dscl . -create "/Users/$name" UniqueID "$next_id"
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echo " $name migrated to uid: $next_id"
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((user_n++))
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name="$(nix_user_n "$user_n")"
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done
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if ((user_n == 1)); then
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echo "Didn't find _nixbld1. Perhaps you have single-user Nix?"
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exit 1
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else
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echo "Migrated $((user_n - 1)) users. If you want to double-check, try:"
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echo "dscl . list /Users UniqueID | grep _nixbld | sort -n -k2"
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fi
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}
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needs_migration(){
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local name uid next_id user_n
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((next_id=NEW_NIX_FIRST_BUILD_UID))
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((user_n=1))
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while read -r name uid; do
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expected_name="$(nix_user_n "$user_n")"
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if [[ "$expected_name" != "$name" ]]; then
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return 0
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fi
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if [[ "$next_id" != "$uid" ]]; then
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return 0
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fi
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((next_id++))
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((user_n++))
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done < <(dscl . list /Users UniqueID | grep _nixbld | sort -n -k2)
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return 1
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}
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if any_nixbld; then
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if needs_migration; then
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echo "Attempting to migrate _nixbld users."
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temporarily_move_existing_nixbld_uids
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change_nixbld_uids
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else
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echo "_nixbld users already appear to be migrated."
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fi
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else
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echo "Didn't find any _nixbld users. Perhaps you have single-user Nix?"
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exit 1
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fi

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