ci: harden secret handling — tmpfs in /dev/shm, file-based passphrase, netrc auth, EXIT trap

.gitea/workflows/build-publish.yml

@@ -9,29 +9,31 @@ jobs:
   build:
     runs-on: ubuntu-22.04
     steps:
-      - name: Checkout
+      - name: Checkout source
         uses: actions/checkout@v4
 
-      - name: Install build deps
+      - name: Install build dependencies
         run: |
+          set -euo pipefail
           sudo apt-get update -y
           sudo apt-get install -y --no-install-recommends \
             git curl wget ca-certificates dpkg-dev fakeroot \
             build-essential gnupg dpkg-sig
 
-      - name: Build NGINX (run.sh new + build + postfix)
+      - name: Compile nginx and modules
         run: |
+          set -euo pipefail
           sudo touch /.dockerenv
           sudo bash build/run.sh new
           sudo bash build/run.sh build
           sudo bash build/run.sh postfix
 
-      - name: Package .deb
+      - name: Assemble .deb package
         id: pkg
         run: |
-          set -e
+          set -euo pipefail
           PKG_NAME="twiy"
-          VERSION=$(nginx -v 2>&1 | awk -F'/' '{print $2}')
+          VERSION="$(nginx -v 2>&1 | awk -F'/' '{print $2}')"
           ARCH="amd64"
           PKG_DIR="/opt/${PKG_NAME}_${VERSION}_${ARCH}"
           DEB_DIR="${PKG_DIR}/DEBIAN"
@@ -60,7 +62,7 @@ jobs:
           Priority: optional
           Architecture: ${ARCH}
           Maintainer: Julio <me@julio.al>
-          Description: Nginx L7 DDoS Protection (The-World-Is-Yours) built by RAWeb CI.
+          Description: Nginx L7 DDoS Protection (The-World-Is-Yours), built by RAWeb CI.
           EOF
 
           sudo tee "${DEB_DIR}/postinst" >/dev/null <<'EOF'
@@ -72,68 +74,88 @@ jobs:
 
           sudo dpkg-deb --build "${PKG_DIR}"
           DEB_FILE="${PKG_DIR}.deb"
-          echo "deb_file=${DEB_FILE}" >> "$GITHUB_OUTPUT"
-          echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
-          echo "pkg_name=${PKG_NAME}" >> "$GITHUB_OUTPUT"
+          sudo chown "$(id -u):$(id -g)" "${DEB_FILE}"
+
+          {
+            echo "deb_file=${DEB_FILE}"
+            echo "version=${VERSION}"
+            echo "pkg_name=${PKG_NAME}"
+          } >> "$GITHUB_OUTPUT"
+
           ls -la "${DEB_FILE}"
           sha256sum "${DEB_FILE}"
 
-      - name: Import GPG key + sign .deb
+      - name: Sign and publish to Nexus
         env:
           GPG_PRIVATE_KEY: ${{ secrets.GPG_PRIVATE_KEY }}
           GPG_PASSPHRASE:  ${{ secrets.GPG_PASSPHRASE }}
           GPG_KEY_ID:      ${{ secrets.GPG_KEY_ID }}
+          NEXUS_USER:      ${{ secrets.NEXUS_USER }}
+          NEXUS_PASS:      ${{ secrets.NEXUS_PASS }}
+          NEXUS_URL:       ${{ secrets.NEXUS_URL }}
+          NEXUS_REPO:      ${{ secrets.NEXUS_REPO }}
           DEB_FILE:        ${{ steps.pkg.outputs.deb_file }}
+          PKG_NAME:        ${{ steps.pkg.outputs.pkg_name }}
         run: |
-          set -e
-          export GNUPGHOME="$(mktemp -d)"
-          chmod 700 "$GNUPGHOME"
-          echo "$GPG_PRIVATE_KEY" | gpg --batch --import
-          # Pre-cache passphrase via gpg-agent so dpkg-sig can sign non-interactively
-          echo "allow-loopback-pinentry"   >> "$GNUPGHOME/gpg-agent.conf"
-          echo "pinentry-mode loopback"    >> "$GNUPGHOME/gpg.conf"
-          gpg-connect-agent reloadagent /bye >/dev/null
-          # Sign with dpkg-sig (preferred) — falls back to debsigs if dpkg-sig missing
-          if command -v dpkg-sig >/dev/null; then
-            sudo --preserve-env=GNUPGHOME,GPG_PASSPHRASE dpkg-sig \
-              -k "$GPG_KEY_ID" \
-              -g "--batch --pinentry-mode loopback --passphrase $GPG_PASSPHRASE" \
-              --sign builder "$DEB_FILE"
-          fi
-          # Verify the signature is present (informational)
-          dpkg-sig --verify "$DEB_FILE" || true
+          set -euo pipefail
+          umask 077
 
-      - name: Publish to apt.julio.al/${{ secrets.NEXUS_REPO }}
-        env:
-          NEXUS_URL:  ${{ secrets.NEXUS_URL }}
-          NEXUS_REPO: ${{ secrets.NEXUS_REPO }}
-          NEXUS_USER: ${{ secrets.NEXUS_USER }}
-          NEXUS_PASS: ${{ secrets.NEXUS_PASS }}
-          DEB_FILE:   ${{ steps.pkg.outputs.deb_file }}
-          PKG_NAME:   ${{ steps.pkg.outputs.pkg_name }}
-        run: |
-          set -e
-          # Best-effort: delete an existing same-named component so re-publishes overwrite cleanly
-          COMPONENT_ID=$(curl -s -u "${NEXUS_USER}:${NEXUS_PASS}" \
-            "${NEXUS_URL}/service/rest/v1/components?repository=${NEXUS_REPO}" \
-            | python3 -c "
-          import sys, json
-          d=json.load(sys.stdin)
-          for c in d.get('items', []):
-              if c.get('name') == '${PKG_NAME}':
-                  print(c.get('id')); break
-          " || true)
-          if [ -n "$COMPONENT_ID" ]; then
-            echo "Removing previous ${PKG_NAME} component ${COMPONENT_ID}"
-            curl -s -u "${NEXUS_USER}:${NEXUS_PASS}" -X DELETE \
-              "${NEXUS_URL}/service/rest/v1/components/${COMPONENT_ID}"
+          # Tmpfs (RAM-only) scratch for every byte of secret material.
+          # Falls back to /tmp if /dev/shm is absent.
+          SECDIR="$(mktemp -d -p /dev/shm raweb-XXXXXXXX 2>/dev/null \
+                    || mktemp -d -t raweb-XXXXXXXX)"
+          chmod 700 "$SECDIR"
+          export GNUPGHOME="$SECDIR/gnupg"
+
+          cleanup() {
+            (gpg --batch --yes --quiet \
+                  --delete-secret-and-public-key "$GPG_KEY_ID" 2>/dev/null) || true
+            (gpgconf --kill all 2>/dev/null) || true
+            find "$SECDIR" -type f -exec shred -uz {} + 2>/dev/null || true
+            rm -rf "$SECDIR"
+          }
+          trap cleanup EXIT
+
+          # Materialise secrets to in-memory files. After this, drop them from env
+          # so any subprocess (or accidental `env`) cannot read them.
+          printf '%s' "$GPG_PRIVATE_KEY" > "$SECDIR/key.asc"
+          printf '%s' "$GPG_PASSPHRASE"  > "$SECDIR/pp"
+          printf 'machine apt.julio.al login %s password %s\n' \
+                 "$NEXUS_USER" "$NEXUS_PASS" > "$SECDIR/netrc"
+          unset GPG_PRIVATE_KEY GPG_PASSPHRASE NEXUS_PASS NEXUS_USER
+
+          # Ephemeral keyring on tmpfs.
+          mkdir -p "$GNUPGHOME"; chmod 700 "$GNUPGHOME"
+          printf 'allow-loopback-pinentry\n' > "$GNUPGHOME/gpg-agent.conf"
+          printf 'pinentry-mode loopback\n'  > "$GNUPGHOME/gpg.conf"
+          gpg --batch --import "$SECDIR/key.asc"
+
+          # Sign the .deb. Passphrase passed via FILE — never argv, never env.
+          dpkg-sig -k "$GPG_KEY_ID" \
+                   -g "--batch --pinentry-mode loopback --passphrase-file $SECDIR/pp" \
+                   --sign builder "$DEB_FILE"
+          dpkg-sig --verify "$DEB_FILE"
+
+          # Replace any prior component of the same name (best-effort).
+          OLD_ID="$(curl -fsS --netrc-file "$SECDIR/netrc" \
+                    "$NEXUS_URL/service/rest/v1/components?repository=$NEXUS_REPO" \
+                    | PKG_NAME="$PKG_NAME" python3 -c '
+          import sys, json, os
+          for c in json.load(sys.stdin).get("items", []):
+              if c.get("name") == os.environ["PKG_NAME"]:
+                  print(c["id"]); break
+          ' || true)"
+          if [ -n "$OLD_ID" ]; then
+            curl -fsS -X DELETE --netrc-file "$SECDIR/netrc" \
+                 "$NEXUS_URL/service/rest/v1/components/$OLD_ID" -o /dev/null
           fi
 
-          HTTP=$(curl -s -o /tmp/upload.out -w '%{http_code}' \
-            -u "${NEXUS_USER}:${NEXUS_PASS}" \
-            -X POST \
-            -F "apt.asset=@${DEB_FILE}" \
-            "${NEXUS_URL}/service/rest/v1/components?repository=${NEXUS_REPO}")
-          echo "Upload HTTP: $HTTP"
-          [ "$HTTP" = "204" ] || [ "$HTTP" = "201" ] || { cat /tmp/upload.out; exit 1; }
-          echo "Published $(basename "$DEB_FILE") to ${NEXUS_URL}/repository/${NEXUS_REPO}/"
+          # Upload — auth via netrc (not -u, not query string).
+          HTTP="$(curl -sS --netrc-file "$SECDIR/netrc" \
+                  -o "$SECDIR/upload.body" -w '%{http_code}' \
+                  -X POST -F "apt.asset=@$DEB_FILE" \
+                  "$NEXUS_URL/service/rest/v1/components?repository=$NEXUS_REPO")"
+          case "$HTTP" in
+            201|204) echo "Uploaded $(basename "$DEB_FILE") to $NEXUS_URL/repository/$NEXUS_REPO/" ;;
+            *) echo "Upload failed (HTTP $HTTP)"; head -c 400 "$SECDIR/upload.body"; exit 1 ;;
+          esac