libsql: Add authorizer support (#2020)

This adds support for `sqlite3_set_authorizer()`. The API follows
rusqlite and the enumerations are lifted straight from rusqlite for
compatibility.

Author: penberg

libsql/src/auth.rs

@@ -0,0 +1,263 @@
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct AuthContext<'a> {
+    pub action: AuthAction<'a>,
+
+    pub database_name: Option<&'a str>,
+
+    pub accessor: Option<&'a str>,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum AuthAction<'a> {
+    Unknown {
+        code: i32,
+        arg1: Option<&'a str>,
+        arg2: Option<&'a str>,
+    },
+    CreateIndex {
+        index_name: &'a str,
+        table_name: &'a str,
+    },
+    CreateTable {
+        table_name: &'a str,
+    },
+    CreateTempIndex {
+        index_name: &'a str,
+        table_name: &'a str,
+    },
+    CreateTempTable {
+        table_name: &'a str,
+    },
+    CreateTempTrigger {
+        trigger_name: &'a str,
+        table_name: &'a str,
+    },
+    CreateTempView {
+        view_name: &'a str,
+    },
+    CreateTrigger {
+        trigger_name: &'a str,
+        table_name: &'a str,
+    },
+    CreateView {
+        view_name: &'a str,
+    },
+    Delete {
+        table_name: &'a str,
+    },
+    DropIndex {
+        index_name: &'a str,
+        table_name: &'a str,
+    },
+    DropTable {
+        table_name: &'a str,
+    },
+    DropTempIndex {
+        index_name: &'a str,
+        table_name: &'a str,
+    },
+    DropTempTable {
+        table_name: &'a str,
+    },
+    DropTempTrigger {
+        trigger_name: &'a str,
+        table_name: &'a str,
+    },
+    DropTempView {
+        view_name: &'a str,
+    },
+    DropTrigger {
+        trigger_name: &'a str,
+        table_name: &'a str,
+    },
+    DropView {
+        view_name: &'a str,
+    },
+    Insert {
+        table_name: &'a str,
+    },
+    Pragma {
+        pragma_name: &'a str,
+        pragma_value: Option<&'a str>,
+    },
+    Read {
+        table_name: &'a str,
+        column_name: &'a str,
+    },
+    Select,
+    Transaction {
+        operation: TransactionOperation,
+    },
+    Update {
+        table_name: &'a str,
+        column_name: &'a str,
+    },
+    Attach {
+        filename: &'a str,
+    },
+    Detach {
+        database_name: &'a str,
+    },
+    AlterTable {
+        database_name: &'a str,
+        table_name: &'a str,
+    },
+    Reindex {
+        index_name: &'a str,
+    },
+    Analyze {
+        table_name: &'a str,
+    },
+    CreateVtable {
+        table_name: &'a str,
+        module_name: &'a str,
+    },
+    DropVtable {
+        table_name: &'a str,
+        module_name: &'a str,
+    },
+    Function {
+        function_name: &'a str,
+    },
+    Savepoint {
+        operation: TransactionOperation,
+        savepoint_name: &'a str,
+    },
+    Recursive,
+}
+
+#[cfg(feature = "core")]
+impl<'a> AuthAction<'a> {
+    pub(crate) fn from_raw(code: i32, arg1: Option<&'a str>, arg2: Option<&'a str>) -> Self {
+        use libsql_sys::ffi;
+
+        match (code, arg1, arg2) {
+            (ffi::SQLITE_CREATE_INDEX, Some(index_name), Some(table_name)) => Self::CreateIndex {
+                index_name,
+                table_name,
+            },
+            (ffi::SQLITE_CREATE_TABLE, Some(table_name), _) => Self::CreateTable { table_name },
+            (ffi::SQLITE_CREATE_TEMP_INDEX, Some(index_name), Some(table_name)) => {
+                Self::CreateTempIndex {
+                    index_name,
+                    table_name,
+                }
+            }
+            (ffi::SQLITE_CREATE_TEMP_TABLE, Some(table_name), _) => {
+                Self::CreateTempTable { table_name }
+            }
+            (ffi::SQLITE_CREATE_TEMP_TRIGGER, Some(trigger_name), Some(table_name)) => {
+                Self::CreateTempTrigger {
+                    trigger_name,
+                    table_name,
+                }
+            }
+            (ffi::SQLITE_CREATE_TEMP_VIEW, Some(view_name), _) => {
+                Self::CreateTempView { view_name }
+            }
+            (ffi::SQLITE_CREATE_TRIGGER, Some(trigger_name), Some(table_name)) => {
+                Self::CreateTrigger {
+                    trigger_name,
+                    table_name,
+                }
+            }
+            (ffi::SQLITE_CREATE_VIEW, Some(view_name), _) => Self::CreateView { view_name },
+            (ffi::SQLITE_DELETE, Some(table_name), None) => Self::Delete { table_name },
+            (ffi::SQLITE_DROP_INDEX, Some(index_name), Some(table_name)) => Self::DropIndex {
+                index_name,
+                table_name,
+            },
+            (ffi::SQLITE_DROP_TABLE, Some(table_name), _) => Self::DropTable { table_name },
+            (ffi::SQLITE_DROP_TEMP_INDEX, Some(index_name), Some(table_name)) => {
+                Self::DropTempIndex {
+                    index_name,
+                    table_name,
+                }
+            }
+            (ffi::SQLITE_DROP_TEMP_TABLE, Some(table_name), _) => {
+                Self::DropTempTable { table_name }
+            }
+            (ffi::SQLITE_DROP_TEMP_TRIGGER, Some(trigger_name), Some(table_name)) => {
+                Self::DropTempTrigger {
+                    trigger_name,
+                    table_name,
+                }
+            }
+            (ffi::SQLITE_DROP_TEMP_VIEW, Some(view_name), _) => Self::DropTempView { view_name },
+            (ffi::SQLITE_DROP_TRIGGER, Some(trigger_name), Some(table_name)) => Self::DropTrigger {
+                trigger_name,
+                table_name,
+            },
+            (ffi::SQLITE_DROP_VIEW, Some(view_name), _) => Self::DropView { view_name },
+            (ffi::SQLITE_INSERT, Some(table_name), _) => Self::Insert { table_name },
+            (ffi::SQLITE_PRAGMA, Some(pragma_name), pragma_value) => Self::Pragma {
+                pragma_name,
+                pragma_value,
+            },
+            (ffi::SQLITE_READ, Some(table_name), Some(column_name)) => Self::Read {
+                table_name,
+                column_name,
+            },
+            (ffi::SQLITE_SELECT, ..) => Self::Select,
+            (ffi::SQLITE_TRANSACTION, Some(operation_str), _) => Self::Transaction {
+                operation: TransactionOperation::from_str(operation_str),
+            },
+            (ffi::SQLITE_UPDATE, Some(table_name), Some(column_name)) => Self::Update {
+                table_name,
+                column_name,
+            },
+            (ffi::SQLITE_ATTACH, Some(filename), _) => Self::Attach { filename },
+            (ffi::SQLITE_DETACH, Some(database_name), _) => Self::Detach { database_name },
+            (ffi::SQLITE_ALTER_TABLE, Some(database_name), Some(table_name)) => Self::AlterTable {
+                database_name,
+                table_name,
+            },
+            (ffi::SQLITE_REINDEX, Some(index_name), _) => Self::Reindex { index_name },
+            (ffi::SQLITE_ANALYZE, Some(table_name), _) => Self::Analyze { table_name },
+            (ffi::SQLITE_CREATE_VTABLE, Some(table_name), Some(module_name)) => {
+                Self::CreateVtable {
+                    table_name,
+                    module_name,
+                }
+            }
+            (ffi::SQLITE_DROP_VTABLE, Some(table_name), Some(module_name)) => Self::DropVtable {
+                table_name,
+                module_name,
+            },
+            (ffi::SQLITE_FUNCTION, _, Some(function_name)) => Self::Function { function_name },
+            (ffi::SQLITE_SAVEPOINT, Some(operation_str), Some(savepoint_name)) => Self::Savepoint {
+                operation: TransactionOperation::from_str(operation_str),
+                savepoint_name,
+            },
+            (ffi::SQLITE_RECURSIVE, ..) => Self::Recursive,
+            (code, arg1, arg2) => Self::Unknown { code, arg1, arg2 },
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum TransactionOperation {
+    Unknown,
+    Begin,
+    Release,
+    Rollback,
+}
+
+#[cfg(feature = "core")]
+impl TransactionOperation {
+    fn from_str(op_str: &str) -> Self {
+        match op_str {
+            "BEGIN" => Self::Begin,
+            "RELEASE" => Self::Release,
+            "ROLLBACK" => Self::Rollback,
+            _ => Self::Unknown,
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum Authorization {
+    Allow,
+    Ignore,
+    Deny,
+}

libsql/src/connection.rs

@@ -4,12 +4,15 @@ use std::path::Path;
 use std::sync::Arc;
 use std::time::Duration;
 
+use crate::auth::{AuthContext, Authorization};
 use crate::params::{IntoParams, Params};
 use crate::rows::Rows;
 use crate::statement::Statement;
 use crate::transaction::Transaction;
 use crate::{Result, TransactionBehavior};
 
+pub type AuthHook = Arc<dyn Fn(&AuthContext) -> Authorization>;
+
 #[async_trait::async_trait]
 pub(crate) trait Conn {
     async fn execute(&self, sql: &str, params: Params) -> Result<u64>;
@@ -43,6 +46,10 @@ pub(crate) trait Conn {
     fn load_extension(&self, _dylib_path: &Path, _entry_point: Option<&str>) -> Result<()> {
         Err(crate::Error::LoadExtensionNotSupported)
     }
+
+    fn authorizer(&self, _hook: Option<AuthHook>) -> Result<()> {
+        Err(crate::Error::AuthorizerNotSupported)
+    }
 }
 
 /// A set of rows returned from `execute_batch`/`execute_transactional_batch`. It is essentially
@@ -258,6 +265,10 @@ impl Connection {
     ) -> Result<()> {
         self.conn.load_extension(dylib_path.as_ref(), entry_point)
     }
+
+    pub fn authorizer(&self, hook: Option<AuthHook>) -> Result<()> {
+        self.conn.authorizer(hook)
+    }
 }
 
 impl fmt::Debug for Connection {

libsql/src/errors.rs

@@ -21,6 +21,8 @@ pub enum Error {
     SyncNotSupported(String), // Not in rusqlite
     #[error("Loading extension is only supported in local databases.")]
     LoadExtensionNotSupported, // Not in rusqlite
+    #[error("Authorizer is only supported in local databases.")]
+    AuthorizerNotSupported, // Not in rusqlite
     #[error("Column not found: {0}")]
     ColumnNotFound(i32), // Not in rusqlite
     #[error("Hrana: `{0}`")]

libsql/src/lib.rs

@@ -153,6 +153,7 @@ pub use errors::Error;
 
 pub use params::params_from_iter;
 
+mod auth;
 mod connection;
 mod database;
 mod load_extension_guard;
@@ -176,7 +177,8 @@ cfg_hrana! {
 }
 
 pub use self::{
-    connection::{BatchRows, Connection},
+    auth::{AuthAction, AuthContext, Authorization},
+    connection::{AuthHook, BatchRows, Connection},
     database::{Builder, Database},
     load_extension_guard::LoadExtensionGuard,
     rows::{Column, Row, Rows},