Automate regeneration of PAM bindings (#882)

.github/workflows/ci.yaml

@@ -284,6 +284,36 @@ jobs:
       - name: Run tests
         run: cargo miri test --workspace --all-features miri
 
+  check-bindings:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install dependencies
+        run: |
+          sudo apt update
+          sudo apt install libpam0g-dev
+
+      - name: Rust Cache
+        uses: Swatinem/rust-cache@v2
+        with:
+          shared-key: "msrv"
+
+      - name: Install rust-bindgen
+        uses: taiki-e/install-action@v2
+        with:
+          tool: [email protected]
+
+      - name: Install cargo-minify
+        run: cargo install --locked --git https://github.com/tweedegolf/cargo-minify cargo-minify
+
+      - name: Regenerate bindings
+        run: make -B pam-sys
+
+      - name: Check for differences
+        run: git diff --exit-code
+
   format:
     runs-on: ubuntu-latest
     env:

Makefile

@@ -1,6 +1,6 @@
 PAM_SRC_DIR = src/pam
 
-BINDGEN_CMD = bindgen --allowlist-function '^pam_.*$$' --allowlist-var '^PAM_.*$$' --opaque-type pam_handle_t --ctypes-prefix libc
+BINDGEN_CMD = bindgen --allowlist-function '^pam_.*$$' --allowlist-var '^PAM_.*$$' --opaque-type pam_handle_t --blocklist-function pam_vsyslog --blocklist-function pam_vprompt --blocklist-type '.*va_list.*' --ctypes-prefix libc --no-layout-tests --sort-semantically
 
 .PHONY: all clean pam-sys pam-sys-diff
 
@@ -13,6 +13,9 @@ pam-sys: $(PAM_SRC_DIR)/sys.rs
 
 $(PAM_SRC_DIR)/sys.rs: $(PAM_SRC_DIR)/wrapper.h
 	$(BINDGEN_CMD) $< --output $@
+	cargo minify --apply --allow-dirty
+	sed -i.bak 's/rust-bindgen \w*\.\w*\.\w*/\0, minified by cargo-minify/' $@
+	rm $@.bak
 
 clean:
 	rm $(PAM_SRC_DIR)/sys.rs

src/pam/converse.rs

@@ -25,7 +25,7 @@ impl PamMessageStyle {
     pub fn from_int(val: libc::c_int) -> Option<PamMessageStyle> {
         use PamMessageStyle::*;
 
-        match val {
+        match val as _ {
             PAM_PROMPT_ECHO_OFF => Some(PromptEchoOff),
             PAM_PROMPT_ECHO_ON => Some(PromptEchoOn),
             PAM_ERROR_MSG => Some(ErrorMessage),

src/pam/error.rs

@@ -68,7 +68,7 @@ impl PamErrorType {
     pub(super) fn from_int(errno: libc::c_int) -> PamErrorType {
         use PamErrorType::*;
 
-        match errno {
+        match errno as _ {
             PAM_SUCCESS => Success,
             PAM_OPEN_ERR => OpenError,
             PAM_SYMBOL_ERR => SymbolError,

src/pam/mod.rs

@@ -142,7 +142,7 @@ impl<C: Converser> PamContext<C> {
     /// Get the PAM flag value for the silent flag
     fn silent_flag(&self) -> i32 {
         if self.silent {
-            PAM_SILENT
+            PAM_SILENT as _
         } else {
             0
         }
@@ -153,7 +153,7 @@ impl<C: Converser> PamContext<C> {
         if self.allow_null_auth_token {
             0
         } else {
-            PAM_DISALLOW_NULL_AUTHTOK
+            PAM_DISALLOW_NULL_AUTHTOK as _
         }
     }
 
@@ -202,15 +202,19 @@ impl<C: Converser> PamContext<C> {
         // SAFETY: `self.pamh` contains a correct handle (obtained from `pam_start`); furthermore,
         // `c_user.as_ptr()` will point to a correct null-terminated string.
         pam_err(unsafe {
-            pam_set_item(self.pamh, PAM_USER, c_user.as_ptr() as *const libc::c_void)
+            pam_set_item(
+                self.pamh,
+                PAM_USER as _,
+                c_user.as_ptr() as *const libc::c_void,
+            )
         })
     }
 
     /// Get the user that is currently active in the PAM handle
     pub fn get_user(&mut self) -> PamResult<String> {
         let mut data = std::ptr::null();
         // SAFETY: `self.pamh` contains a correct handle (obtained from `pam_start`)
-        pam_err(unsafe { pam_get_item(self.pamh, PAM_USER, &mut data) })?;
+        pam_err(unsafe { pam_get_item(self.pamh, PAM_USER as _, &mut data) })?;
 
         // safety check to make sure that we were not passed a null pointer by PAM,
         // or that in fact PAM did not write to `data` at all.
@@ -230,15 +234,27 @@ impl<C: Converser> PamContext<C> {
         let data = CString::new(tty_path.as_ref().as_bytes())?;
         // SAFETY: `self.pamh` contains a correct handle (obtained from `pam_start`); furthermore,
         // `data.as_ptr()` will point to a correct null-terminated string.
-        pam_err(unsafe { pam_set_item(self.pamh, PAM_TTY, data.as_ptr() as *const libc::c_void) })
+        pam_err(unsafe {
+            pam_set_item(
+                self.pamh,
+                PAM_TTY as _,
+                data.as_ptr() as *const libc::c_void,
+            )
+        })
     }
 
     // Set the user that requested the actions in this PAM instance.
     pub fn set_requesting_user(&mut self, user: &str) -> PamResult<()> {
         let data = CString::new(user.as_bytes())?;
         // SAFETY: `self.pamh` contains a correct handle (obtained from `pam_start`); furthermore,
         // `data.as_ptr()` will point to a correct null-terminated string.
-        pam_err(unsafe { pam_set_item(self.pamh, PAM_RUSER, data.as_ptr() as *const libc::c_void) })
+        pam_err(unsafe {
+            pam_set_item(
+                self.pamh,
+                PAM_RUSER as _,
+                data.as_ptr() as *const libc::c_void,
+            )
+        })
     }
 
     /// Re-initialize the credentials stored in PAM
@@ -264,7 +280,7 @@ impl<C: Converser> PamContext<C> {
         let mut flags = 0;
         flags |= self.silent_flag();
         if expired_only {
-            flags |= PAM_CHANGE_EXPIRED_AUTHTOK;
+            flags |= PAM_CHANGE_EXPIRED_AUTHTOK as libc::c_int;
         }
         // SAFETY: `self.pamh` contains a correct handle (obtained from `pam_start`).
         pam_err(unsafe { pam_chauthtok(self.pamh, flags) })
@@ -382,7 +398,8 @@ impl<C: Converser> Drop for PamContext<C> {
         unsafe {
             pam_end(
                 self.pamh,
-                self.last_pam_status.unwrap_or(PAM_SUCCESS as libc::c_int) | PAM_DATA_SILENT,
+                self.last_pam_status.unwrap_or(PAM_SUCCESS as libc::c_int)
+                    | PAM_DATA_SILENT as libc::c_int,
             )
         };
     }