--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libpam-sys/src/ffi.rs	Wed Jul 30 17:53:31 2025 -0400
@@ -0,0 +1,438 @@
+use std::ffi::{c_char, c_int, c_uint, c_void};
+use std::fmt;
+use std::marker::{PhantomData, PhantomPinned};
+
+/// An opaque structure that PAM uses to communicate.
+///
+/// This is only ever returned in pointer form and cannot be constructed.
+#[repr(C)]
+pub struct pam_handle {
+    _value: (),
+    _marker: PhantomData<(PhantomPinned, *mut c_void)>,
+}
+
+impl fmt::Debug for pam_handle {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "pam_handle({self:p}")
+    }
+}
+
+/// Used by PAM to communicate between the module and the application.
+#[repr(C)]
+#[derive(Debug)]
+pub struct pam_conv {
+    pub conv: unsafe extern "C" fn(
+        num_msg: c_int,
+        msg: *const *const pam_message,
+        resp: *mut *mut pam_response,
+        appdata: *mut c_void,
+    ) -> c_int,
+    pub appdata_ptr: *mut c_void,
+}
+
+/// A message sent into a PAM conversation.
+#[repr(C)]
+#[derive(Debug)]
+pub struct pam_message {
+    pub msg_style: c_int,
+    pub msg: *const c_char,
+}
+
+/// A response returned from a PAM conversation.
+#[repr(C)]
+#[derive(Debug)]
+pub struct pam_response {
+    pub resp: *mut c_char,
+    /// Completely unused.
+    pub resp_retcode: c_int,
+}
+
+/// Definition of the PAM_XAUTHDATA item. Compatible with `xcb_auth_info_t`.
+#[cfg(pam_impl = "LinuxPam")]
+#[repr(C)]
+pub struct pam_xauth_data {
+    pub namelen: c_int,
+    pub name: *mut c_char,
+    pub datalen: c_int,
+    pub data: *mut c_char,
+}
+
+#[cfg(pam_impl = "LinuxPam")]
+#[derive(Debug)]
+#[repr(C)]
+pub struct pam_modutil_privs {
+    pub grplist: *mut libc::gid_t,
+    pub number_of_groups: c_int,
+    pub allocated: c_int,
+    pub old_gid: libc::gid_t,
+    pub old_uid: libc::uid_t,
+    pub is_dropped: c_int,
+}
+
+#[cfg(pam_impl = "OpenPam")]
+pub type pam_func_t = unsafe extern "C" fn(
+    handle: *mut pam_handle,
+    flags: c_int,
+    argc: c_int,
+    argv: *const *const c_char,
+) -> c_int;
+
+#[cfg(pam_impl = "OpenPam")]
+#[derive(Debug)]
+#[repr(C)]
+pub struct pam_module {
+    pub path: *mut c_char,
+    pub func: [pam_func_t; 6],
+    pub dlh: *mut c_void,
+}
+
+#[cfg(any(pam_impl = "OpenPam", pam_impl = "Sun"))]
+#[derive(Debug)]
+#[repr(C)]
+pub struct pam_repository {
+    pub type_: *mut c_char,
+    pub scope: *mut c_void,
+    pub scope_len: usize,
+}
+
+// These are the functions specified in X/SSO. Everybody exports them.
+extern "C" {
+    /// Account validation.
+    pub fn pam_acct_mgmt(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    /// Authenticate a user.
+    pub fn pam_authenticate(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    // Nobody implements pam_authenticate_secondary.
+
+    /// Manage authentication tokens.
+    pub fn pam_chauthtok(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    /// Close an opened user session.
+    pub fn pam_close_session(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    /// Ends the PAM transaction.
+    pub fn pam_end(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    /// Gets module-specific data. PAM still owns the data.
+    pub fn pam_get_data(
+        pamh: *const pam_handle,
+        module_data_name: *const c_char,
+        data: *mut *const c_void,
+    ) -> c_int;
+
+    /// Gets an environment variable.  You own the return value.
+    pub fn pam_getenv(pamh: *const pam_handle, name: *const c_char) -> *mut c_char;
+
+    /// Gets all the environment variables.  You own everything it points to.
+    pub fn pam_getenvlist(pamh: *const pam_handle) -> *mut *mut c_char;
+
+    /// Get information about the transaction.
+    ///
+    /// The item is owned by PAM.
+    pub fn pam_get_item(
+        pamh: *const pam_handle,
+        item_type: c_int,
+        item: *mut *const c_void,
+    ) -> c_int;
+
+    // Nobody implements pam_get_mapped_authtok.
+    // Nobody implements pam_get_mapped_username.
+
+    /// Get the username. PAM owns it.
+    pub fn pam_get_user(
+        pamh: *mut pam_handle,
+        user: *mut *const c_char,
+        prompt: *const c_char,
+    ) -> c_int;
+
+    /// Opens a user session.
+    pub fn pam_open_session(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    /// Sets the value of an environment variable. `namevalue` is copied.
+    pub fn pam_putenv(pamh: *mut pam_handle, namevalue: *const c_char) -> c_int;
+
+    /// Update or delete user credentials.
+    pub fn pam_setcred(pamh: *mut pam_handle, flags: c_int) -> c_int;
+
+    /// Set module-specific data. PAM will call `cleanup` when completed.
+    pub fn pam_set_data(
+        pamh: *mut pam_handle,
+        module_data_name: *const c_char,
+        data: *mut c_void,
+        cleanup: unsafe extern "C" fn(
+            pamh: *mut pam_handle,
+            data: *mut c_void,
+            pam_end_status: c_int,
+        ),
+    ) -> c_int;
+
+    /// Set information about the transaction.  The `item` is copied.
+    pub fn pam_set_item(pamh: *mut pam_handle, item_type: c_int, item: *const c_void) -> c_int;
+
+    // Nobody implements pam_set_mapped_authtok.
+    // Nobody implements pam_set_mapped_username.
+
+    // The pam_sm_whatever functions are prototypes for the functions that
+    // a PAM module should implement, not symbols provided by PAM.
+
+    /// Starts a PAM transaction.  The `conv` may or may not be copied.
+    pub fn pam_start(
+        service: *const c_char,
+        user: *const c_char,
+        pam_conv: *mut pam_conv,
+        pamh: *mut *mut pam_handle,
+    ) -> c_int;
+
+    /// Gets a statically-allocated error string.
+    ///
+    /// All implementations of PAM known to this library (Linux-PAM, OpenPAM,
+    /// and Sun) ignore `pamh` and will accept a null pointer.
+    pub fn pam_strerror(pamh: *const pam_handle, error_number: c_int) -> *mut c_char;
+}
+
+#[cfg(any(pam_impl = "LinuxPam", pam_impl = "OpenPam"))]
+extern "C" {
+    /// Gets `PAM_AUTHTOK`, or asks the user if that is unset.
+    pub fn pam_get_authtok(
+        pamh: *mut pam_handle,
+        item: c_int,
+        authtok: *mut *const c_char,
+        prompt: *const c_char,
+    ) -> c_int;
+
+    pub fn pam_prompt(
+        pamh: *const pam_handle,
+        style: c_int,
+        response: *mut *mut c_char,
+        fmt: *const c_char,
+        ...
+    ) -> c_int;
+
+}
+
+#[cfg(pam_impl = "LinuxPam")]
+extern "C" {
+    pub fn pam_fail_delay(pamh: *mut pam_handle, musec_delay: c_uint) -> c_int;
+
+    /// Start a PAM transaction based on configuration in the given directory.
+    pub fn pam_start_confdir(
+        service_name: *const c_char,
+        user: *const c_char,
+        pam_conversation: *mut pam_conv,
+        confdir: *const c_char,
+        pamh: *mut *mut pam_handle,
+    ) -> c_int;
+
+    // We don't export the v-variants of the formatting functions.
+
+    pub fn pam_syslog(pamh: *const pam_handle, priority: c_int, fmt: *const c_char, ...);
+
+    pub fn pam_get_authtok_noverify(
+        pamh: *const pam_handle,
+        authtok: *mut *const c_char,
+        prompt: *const c_char,
+    ) -> c_int;
+
+    pub fn pam_get_authtok_verify(
+        pamh: *const pam_handle,
+        authtok: *mut *const c_char,
+        prompt: *const c_char,
+    ) -> c_int;
+
+    // pam_modutil also lives in libpam for Linux.
+
+    pub fn pam_modutil_check_user_in_passwd(
+        pamh: *mut pam_handle,
+        user_name: *const c_char,
+        file_name: *const c_char,
+    ) -> c_int;
+
+    pub fn pam_modutil_getpwnam(pamh: *mut pam_handle, user: *const c_char) -> *mut libc::passwd;
+
+    pub fn pam_modutil_getpwuid(pamh: *mut pam_handle, uid: libc::uid_t) -> *mut libc::passwd;
+
+    pub fn pam_modutil_getgrnam(pamh: *mut pam_handle, group: *const c_char) -> *mut libc::group;
+
+    pub fn pam_modutil_getgrgid(pamh: *mut pam_handle, gid: libc::gid_t) -> *mut libc::group;
+
+    pub fn pam_modutil_getspnam(pamh: *mut pam_handle, user: *const c_char) -> *mut libc::spwd;
+
+    pub fn pam_modutil_user_in_group_nam_nam(
+        pamh: *mut pam_handle,
+        user: *const c_char,
+        group: *const c_char,
+    ) -> c_int;
+
+    pub fn pam_modutil_user_in_group_nam_gid(
+        pamh: *mut pam_handle,
+        user: *const c_char,
+        group: libc::gid_t,
+    ) -> c_int;
+
+    pub fn pam_modutil_user_in_group_uid_nam(
+        pamh: *mut pam_handle,
+        user: libc::uid_t,
+        group: *const c_char,
+    ) -> c_int;
+
+    pub fn pam_modutil_user_in_group_uid_gid(
+        pamh: *mut pam_handle,
+        user: libc::uid_t,
+        group: libc::gid_t,
+    ) -> c_int;
+
+    pub fn pam_modutil_getlogin(pamh: *mut pam_handle) -> *const c_char;
+
+    pub fn pam_modutil_read(fd: c_int, buffer: *mut c_char, count: c_int) -> c_int;
+
+    pub fn pam_modutil_write(fd: c_int, buffer: *const c_char, count: c_int) -> c_int;
+
+    pub fn pam_modutil_audit_write(
+        pamh: *mut pam_handle,
+        type_: c_int,
+        message: *const c_char,
+        retval: c_int,
+    ) -> c_int;
+
+    pub fn pam_modutil_drop_priv(
+        pamh: *mut pam_handle,
+        p: *mut pam_modutil_privs,
+        pw: *const libc::passwd,
+    ) -> c_int;
+
+    pub fn pam_modutil_regain_priv(pamh: *mut pam_handle, p: *mut pam_modutil_privs) -> c_int;
+
+    pub fn pam_modutil_sanitize_helper_fds(
+        pamh: *mut pam_handle,
+        redirect_stdin: super::constants::pam_modutil_redirect_fd,
+        redirect_stdout: super::constants::pam_modutil_redirect_fd,
+        redirect_stderr: super::constants::pam_modutil_redirect_fd,
+    ) -> c_int;
+
+    pub fn pam_modutil_search_key(
+        pamh: *mut pam_handle,
+        file_name: *const c_char,
+        key: *const c_char,
+    ) -> *mut c_char;
+}
+
+#[cfg(pam_impl = "OpenPam")]
+extern "C" {
+    pub fn openpam_borrow_cred(pamh: *mut pam_handle, passwd: *const libc::passwd) -> c_int;
+
+    pub fn openpam_subst(
+        pamh: *const pam_handle,
+        buf: *mut c_char,
+        _bufsize: *mut usize,
+        _template: *const c_char,
+    ) -> c_int;
+
+    pub fn openpam_free_data(pamh: *mut pam_handle, data: *mut c_void, status: c_int);
+
+    pub fn openpam_free_envlist(_envlist: *mut *mut c_char);
+
+    pub fn openpam_get_option(_pamh: *mut pam_handle, _option: *const c_char) -> *const c_char;
+
+    pub fn openpam_restore_cred(pamh: *mut pam_handle) -> c_int;
+
+    pub fn openpam_set_option(
+        _pamh: *mut pam_handle,
+        _option: *const c_char,
+        _value: *const c_char,
+    ) -> c_int;
+
+    pub fn pam_error(pamh: *const pam_handle, _fmt: *const c_char, ...) -> c_int;
+
+    pub fn pam_info(_pamh: *const pam_handle, _fmt: *const c_char, ...) -> c_int;
+
+    pub fn openpam_readline(
+        _f: *mut libc::FILE,
+        _lineno: *mut c_int,
+        _lenp: *mut usize,
+    ) -> *mut c_char;
+
+    pub fn openpam_readlinev(
+        _f: *mut libc::FILE,
+        _lineno: *mut c_int,
+        _lenp: *mut c_int,
+    ) -> *mut *mut c_char;
+
+    pub fn openpam_readword(
+        _f: *mut libc::FILE,
+        _lineno: *mut c_int,
+        _lenp: *mut usize,
+    ) -> *mut c_char;
+
+    pub fn openpam_straddch(
+        _str: *mut *mut c_char,
+        _sizep: *mut usize,
+        _lenp: *mut usize,
+        ch: c_int,
+    ) -> c_int;
+
+    pub fn openpam_set_feature(_feature: c_int, _onoff: c_int) -> c_int;
+
+    pub fn openpam_get_feature(_feature: c_int, _onoff: *mut c_int) -> c_int;
+
+    pub fn _openpam_log(_level: c_int, _func: *const c_char, _fmt: *const c_char, ...);
+
+    /// A premade conversation function that talks to the TTY.
+    ///
+    /// ```no_run
+    /// # use std::ffi::CString;
+    /// # use std::ptr;
+    /// use libpam_sys::*;
+    /// # let service = CString::new("whatever").unwrap();
+    /// # let user = CString::new("whatever").unwrap();
+    /// let mut handle: *mut pam_handle = ptr::null_mut();
+    /// let mut conv = pam_conv {
+    ///     conv: openpam_ttyconv,
+    ///     appdata_ptr: ptr::null_mut(),
+    /// };
+    /// let result = unsafe { pam_start(service.as_ptr(), user.as_ptr(), &mut conv, &mut handle) };
+    /// ```
+    pub fn openpam_ttyconv(
+        n: c_int,
+        _msg: *const *const pam_message,
+        _resp: *mut *mut pam_response,
+        _data: *mut c_void,
+    ) -> c_int;
+
+    pub static mut openpam_ttyconv_timeout: c_int;
+
+    /// A null conversation function.
+    ///
+    /// ```no_run
+    /// # use std::ffi::CString;
+    /// # use std::ptr;
+    /// use libpam_sys::*;
+    /// # let service = CString::new("whatever").unwrap();
+    /// # let user = CString::new("whatever").unwrap();
+    /// let mut handle: *mut pam_handle = ptr::null_mut();
+    /// let mut conv = pam_conv {
+    ///     conv: openpam_nullconv,
+    ///     appdata_ptr: ptr::null_mut(),
+    /// };
+    /// let result = unsafe { pam_start(service.as_ptr(), user.as_ptr(), &mut conv, &mut handle) };
+    /// ```
+    pub fn openpam_nullconv(
+        n: c_int,
+        _msg: *const *const pam_message,
+        _resp: *mut *mut pam_response,
+        _data: *mut c_void,
+    ) -> c_int;
+}
+
+#[cfg(pam_impl = "Sun")]
+extern "C" {
+    pub fn __pam_get_authtok(
+        pamh: *mut pam_handle,
+        source: c_int,
+        type_: c_int,
+        prompt: *const c_char,
+        authtok: *mut *mut c_char,
+    ) -> c_int;
+
+    pub fn __pam_log(priority: c_int, format: *const c_char, ...);
+}