fix(easy-docker): pin and verify gum fallback release

scripts/easy-docker/README.md

@@ -16,7 +16,8 @@ bash easy-docker.sh
 - Docker Desktop includes Compose v2 by default; on Linux Engine-only setups you may need the `docker-compose-plugin` package
 - Docker daemon must be running before the TUI starts
 - Required docker commands are validated (`docker ps/exec/inspect/cp` and `docker compose config/up/down/logs/exec/pull/ps`)
-- If package manager installation for `gum` fails, the script can use a GitHub binary fallback
+- If package manager installation for `gum` fails, the script can use a pinned GitHub binary fallback
+- The GitHub fallback is pinned to `gum` `v0.17.0` and verifies SHA256 checksums from `scripts/easy-docker/config/gum-checksums.tsv`
 
 ## Options
 

scripts/easy-docker/config/gum-checksums.tsv

@@ -0,0 +1,7 @@
+# version	asset_name	sha256
+0.17.0	gum_0.17.0_Darwin_arm64.tar.gz	e2a4b8596efa05821d8c58d0c1afbcd7ad1699ba69c689cc3ff23a4a99c8b237
+0.17.0	gum_0.17.0_Darwin_x86_64.tar.gz	cd66576aeebe6cd19c771863c7e8d696e0e1d5387d1e7075666baa67c2052e53
+0.17.0	gum_0.17.0_Linux_arm64.tar.gz	b0b9ed95cbf7c8b7073f17b9591811f5c001e33c7cfd066ca83ce8a07c576f9c
+0.17.0	gum_0.17.0_Linux_armv7.tar.gz	25711c2fbc6887cde79ed586972834121a04955968808dd688c688381ac50ab2
+0.17.0	gum_0.17.0_Linux_x86_64.tar.gz	69ee169bd6387331928864e94d47ed01ef649fbfe875baed1bbf27b5377a6fdb
+0.17.0	gum_0.17.0_Windows_x86_64.zip	b2be80531c6babc8d4e0e6ca95773d58118a2e1582ae006aace08dbc55503072

scripts/easy-docker/lib/install/gum/assets.sh

@@ -1,5 +1,122 @@
 #!/usr/bin/env bash
 
+get_gum_checksums_path() {
+  local gum_lib_dir=""
+
+  gum_lib_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+  printf '%s/../../../config/gum-checksums.tsv\n' "${gum_lib_dir}"
+}
+
+get_pinned_gum_version() {
+  local checksums_path=""
+  local release_version=""
+
+  checksums_path="$(get_gum_checksums_path)"
+  if [ ! -f "${checksums_path}" ]; then
+    return 1
+  fi
+
+  release_version="$(
+    awk -F '\t' '
+      /^[[:space:]]*#/ { next }
+      NF < 3 { next }
+      {
+        print $1
+        exit
+      }
+    ' "${checksums_path}"
+  )"
+  if [ -z "${release_version}" ]; then
+    return 1
+  fi
+
+  printf '%s\n' "${release_version}"
+}
+
+get_pinned_gum_asset_checksum() {
+  local release_version="${1}"
+  local asset_name="${2}"
+  local checksums_path=""
+  local expected_checksum=""
+
+  checksums_path="$(get_gum_checksums_path)"
+  if [ ! -f "${checksums_path}" ]; then
+    return 1
+  fi
+
+  expected_checksum="$(
+    awk -F '\t' -v release_version="${release_version}" -v asset_name="${asset_name}" '
+      /^[[:space:]]*#/ { next }
+      NF < 3 { next }
+      $1 == release_version && $2 == asset_name {
+        print $3
+        exit
+      }
+    ' "${checksums_path}"
+  )"
+  if [ -z "${expected_checksum}" ]; then
+    return 1
+  fi
+
+  printf '%s\n' "${expected_checksum}"
+}
+
+sha256_verification_available() {
+  command_exists sha256sum ||
+    command_exists shasum ||
+    command_exists openssl ||
+    command_exists certutil
+}
+
+compute_file_sha256() {
+  local file_path="${1}"
+  local hash_input_path="${file_path}"
+
+  if command_exists sha256sum; then
+    sha256sum "${file_path}" | awk '{print tolower($1)}'
+    return $?
+  fi
+
+  if command_exists shasum; then
+    shasum -a 256 "${file_path}" | awk '{print tolower($1)}'
+    return $?
+  fi
+
+  if command_exists openssl; then
+    openssl dgst -sha256 -r "${file_path}" | awk '{print tolower($1)}'
+    return $?
+  fi
+
+  if command_exists certutil; then
+    if command_exists cygpath; then
+      hash_input_path="$(cygpath -w "${file_path}" 2>/dev/null || printf '%s' "${file_path}")"
+    fi
+
+    certutil -hashfile "${hash_input_path}" SHA256 2>/dev/null |
+      awk 'NR == 2 { gsub(/ /, "", $0); print tolower($0); exit }'
+    return $?
+  fi
+
+  return 1
+}
+
+verify_file_sha256() {
+  local file_path="${1}"
+  local expected_checksum="${2}"
+  local actual_checksum=""
+
+  actual_checksum="$(compute_file_sha256 "${file_path}" || true)"
+  if [ -z "${actual_checksum}" ]; then
+    return 1
+  fi
+
+  if [ "${actual_checksum}" != "$(printf '%s' "${expected_checksum}" | tr '[:upper:]' '[:lower:]')" ]; then
+    return 1
+  fi
+
+  return 0
+}
+
 get_gum_asset_candidates() {
   local release_version="${1}"
   local gum_os="${2}"
@@ -60,23 +177,3 @@ find_gum_binary() {
 
   return 1
 }
-
-fetch_latest_gum_release_version() {
-  local api_payload=""
-  local tag_name=""
-
-  api_payload="$(curl -fsSL "https://api.github.com/repos/charmbracelet/gum/releases/latest")" || return 1
-
-  if command_exists jq; then
-    tag_name="$(printf '%s' "${api_payload}" | jq -r '.tag_name // empty')"
-  else
-    tag_name="$(printf '%s' "${api_payload}" | sed -n 's/.*"tag_name":[[:space:]]*"\([^"]*\)".*/\1/p' | head -n 1)"
-  fi
-
-  tag_name="${tag_name#v}"
-  if [ -z "${tag_name}" ]; then
-    return 1
-  fi
-
-  printf '%s\n' "${tag_name}"
-}

scripts/easy-docker/lib/install/gum/ensure.sh

@@ -46,7 +46,7 @@ ensure_gum() {
   fi
 
   if should_use_github_fallback; then
-    echo "Trying GitHub release fallback..."
+    echo "Trying pinned GitHub release fallback..."
     if install_gum_from_github_release; then
       hash -r
     fi

scripts/easy-docker/lib/install/gum/github_release.sh

@@ -10,6 +10,7 @@ cleanup_gum_tmp_dir() {
 
 install_gum_from_github_release() {
   local release_version=""
+  local checksums_path=""
   local asset_name=""
   local asset_path=""
   local download_url=""
@@ -20,6 +21,7 @@ install_gum_from_github_release() {
   local target_binary_name="gum"
   local gum_os=""
   local gum_arch=""
+  local expected_checksum=""
 
   if ! command_exists curl; then
     echo "curl is required for the GitHub fallback."
@@ -31,9 +33,20 @@ install_gum_from_github_release() {
     return 1
   fi
 
-  release_version="$(fetch_latest_gum_release_version || true)"
+  release_version="$(get_pinned_gum_version || true)"
   if [ -z "${release_version}" ]; then
-    echo "Could not determine latest gum release version."
+    echo "Could not determine the pinned gum release version."
+    return 1
+  fi
+
+  checksums_path="$(get_gum_checksums_path)"
+  if [ ! -f "${checksums_path}" ]; then
+    echo "Pinned gum checksum file is missing: ${checksums_path}"
+    return 1
+  fi
+
+  if ! sha256_verification_available; then
+    echo "A SHA256 verification tool is required for the GitHub fallback."
     return 1
   fi
 
@@ -45,6 +58,11 @@ install_gum_from_github_release() {
   extract_dir="${tmp_dir}/extract"
 
   while IFS= read -r asset_name; do
+    expected_checksum="$(get_pinned_gum_asset_checksum "${release_version}" "${asset_name}" || true)"
+    if [ -z "${expected_checksum}" ]; then
+      continue
+    fi
+
     asset_path="${tmp_dir}/${asset_name}"
     download_url="https://github.com/charmbracelet/gum/releases/download/v${release_version}/${asset_name}"
 
@@ -52,6 +70,11 @@ install_gum_from_github_release() {
       continue
     fi
 
+    if ! verify_file_sha256 "${asset_path}" "${expected_checksum}"; then
+      echo "Checksum verification failed for ${asset_name}."
+      continue
+    fi
+
     rm -rf "${extract_dir}"
     mkdir -p "${extract_dir}"
 
@@ -67,7 +90,7 @@ install_gum_from_github_release() {
 
   if [ -z "${gum_binary_path}" ]; then
     cleanup_gum_tmp_dir "${tmp_dir}"
-    echo "No compatible gum binary was found in GitHub release assets."
+    echo "No compatible, verified gum binary was found in the pinned GitHub release assets."
     return 1
   fi