Forgot to include the new "auth.c" source file in the previous checkin. (CVS 828)

FossilOrigin-Name: 7601916419489879fe963c83010b452c49ef063f

1 files changed, 215 insertions, 0 deletions

diff --git a/src/auth.c b/src/auth.c
new file mode 100644
index 000000000..92782b85a
--- /dev/null
+++ b/src/auth.c
@@ -0,0 +1,215 @@
+/*
+** 2003 January 11
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains code used to implement the sqlite_set_authorizer()
+** API.  This facility is an optional feature of the library.  Embedded
+** systems that do not need this facility may omit it by recompiling
+** the library with -DSQLITE_OMIT_AUTHORIZATION=1
+**
+** $Id: auth.c,v 1.1 2003/01/12 18:07:49 drh Exp $
+*/
+#include "sqliteInt.h"
+
+/*
+** All of the code in this file may be omitted by defining a single
+** macro.
+*/
+#ifndef SQLITE_OMIT_AUTHORIZATION
+
+/*
+** Set or clear the access authorization function.
+**
+** The access authorization function is be called during the compilation
+** phase to verify that the user has read and/or write access permission
+** various fields of the database.  The first argument to the auth function
+** is a copy of the 3rd argument to this routine.  The second argument
+** to the auth function is one of these constants:
+**
+**        SQLITE_READ_COLUMN
+**        SQLITE_WRITE_COLUMN
+**        SQLITE_DELETE_ROW
+**        SQLITE_INSERT_ROW
+**
+** The third and fourth arguments to the auth function are the name of
+** the table and the column that are being accessed.  The auth function
+** should return either SQLITE_OK, SQLITE_DENY, or SQLITE_IGNORE.  If
+** SQLITE_OK is returned, it means that access is allowed.  SQLITE_DENY
+** means that the SQL statement will never-run - the sqlite_exec() call
+** will return with an error.  SQLITE_IGNORE means that the SQL statement
+** should run but attempts to read the specified column will return NULL
+** and attempts to write the column will be ignored.
+**
+** Setting the auth function to NULL disables this hook.  The default
+** setting of the auth function is NULL.
+*/
+int sqlite_set_authorizer(
+  sqlite *db,
+  int (*xAuth)(void*,int,const char*,const char*),
+  void *pArg
+){
+  db->xAuth = xAuth;
+  db->pAuthArg = pArg;
+  return SQLITE_OK;
+}
+
+/*
+** Write an error message into pParse->zErrMsg that explains that the
+** user-supplied authorization function returned an illegal value.
+*/
+static void sqliteAuthBadReturnCode(Parse *pParse, int rc){
+  char zBuf[20];
+  sprintf(zBuf, "(%d)", rc);
+  sqliteSetString(&pParse->zErrMsg, "illegal return value ", zBuf,
+    " from the authorization function - should to be SQLITE_OK, "
+    "SQLITE_IGNORE, or SQLITE_DENY", 0);
+  pParse->nErr++;
+}
+
+/*
+** The pExpr should be a TK_COLUMN expression.  The table referred to
+** is in pTabList with an offset of base.  Check to see if it is OK to read
+** this particular column.
+**
+** If the auth function returns SQLITE_IGNORE, change the TK_COLUMN 
+** instruction into a TK_NULL.  If the auth function returns SQLITE_DENY,
+** then generate an error.
+*/
+void sqliteAuthRead(
+  Parse *pParse,        /* The parser context */
+  Expr *pExpr,          /* The expression to check authorization on */
+  SrcList *pTabList,    /* All table that pExpr might refer to */
+  int base              /* Offset of pTabList relative to pExpr */
+){
+  sqlite *db = pParse->db;
+  int rc;
+  Table *pTab;
+  const char *zCol;
+  if( db->xAuth==0 ) return;
+  assert( pExpr->op==TK_COLUMN );
+  assert( pExpr->iTable>=base && pExpr->iTable<base+pTabList->nSrc );
+  pTab = pTabList->a[pExpr->iTable-base].pTab;
+  if( pTab==0 ) return;
+  if( pExpr->iColumn>=0 ){
+    assert( pExpr->iColumn<pTab->nCol );
+    zCol = pTab->aCol[pExpr->iColumn].zName;
+  }else if( pTab->iPKey>=0 ){
+    assert( pTab->iPKey<pTab->nCol );
+    zCol = pTab->aCol[pTab->iPKey].zName;
+  }else{
+    zCol = "ROWID";
+  }
+  rc = db->xAuth(db->pAuthArg, SQLITE_READ_COLUMN, pTab->zName, zCol);
+  if( rc==SQLITE_IGNORE ){
+    pExpr->op = TK_NULL;
+  }else if( rc==SQLITE_DENY ){
+    sqliteSetString(&pParse->zErrMsg,"access to ",
+        pTab->zName, ".", zCol, " is prohibited", 0);
+    pParse->nErr++;
+  }else if( rc!=SQLITE_OK ){
+    sqliteAuthBadReturnCode(pParse, rc);
+  }
+}
+
+/*
+** Check the user-supplied authorization function to see if it is ok to
+** delete rows from the table pTab.  Return SQLITE_OK if it is.  Return
+** SQLITE_IGNORE if deletions should be silently omitted.  Return SQLITE_DENY
+** if an error is to be reported.  In the last case, write the text of
+** the error into pParse->zErrMsg.
+*/
+int sqliteAuthDelete(Parse *pParse, const char *zName, int forceError){
+  sqlite *db = pParse->db;
+  int rc;
+  if( db->xAuth==0 ){
+    return SQLITE_OK;
+  }
+  rc = db->xAuth(db->pAuthArg, SQLITE_DELETE_ROW, zName, "");
+  if( rc==SQLITE_DENY  || (rc==SQLITE_IGNORE && forceError) ){
+    sqliteSetString(&pParse->zErrMsg,"deletion of rows from table ",
+        zName, " is prohibited", 0);
+    pParse->nErr++;
+  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
+    rc = SQLITE_DENY;
+    sqliteAuthBadReturnCode(pParse, rc);
+  }
+  return rc;
+}
+
+/*
+** Check the user-supplied authorization function to see if it is ok to
+** insert rows from the table pTab.  Return SQLITE_OK if it is.  Return
+** SQLITE_IGNORE if deletions should be silently omitted.  Return SQLITE_DENY
+** if an error is to be reported.  In the last case, write the text of
+** the error into pParse->zErrMsg.
+*/
+int sqliteAuthInsert(Parse *pParse, const char *zName, int forceError){
+  sqlite *db = pParse->db;
+  int rc;
+  if( db->xAuth==0 ){
+    return SQLITE_OK;
+  }
+  rc = db->xAuth(db->pAuthArg, SQLITE_INSERT_ROW, zName, "");
+  if( rc==SQLITE_DENY || (rc==SQLITE_IGNORE && forceError) ){
+    sqliteSetString(&pParse->zErrMsg,"insertion of rows from table ",
+        zName, " is prohibited", 0);
+    pParse->nErr++;
+  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
+    rc = SQLITE_DENY;
+    sqliteAuthBadReturnCode(pParse, rc);
+  }
+  return rc;
+}
+
+/*
+** Check to see if it is ok to modify column "j" of table pTab.
+** Return SQLITE_OK, SQLITE_IGNORE, or SQLITE_DENY.
+*/
+int sqliteAuthWrite(Parse *pParse, Table *pTab, int j){
+  sqlite *db = pParse->db;
+  int rc;
+  if( db->xAuth==0 ) return SQLITE_OK;
+  rc = db->xAuth(db->pAuthArg, SQLITE_WRITE_COLUMN,
+                    pTab->zName, pTab->aCol[j].zName);
+  if( rc==SQLITE_DENY ){
+      sqliteSetString(&pParse->zErrMsg, "changes to ", pTab->zName,
+          ".", pTab->aCol[j].zName, " are prohibited", 0);
+      pParse->nErr++;
+  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
+    sqliteAuthBadReturnCode(pParse, rc);
+  }
+  return rc;
+}
+
+/*
+** Check to see if it is ok to execute a special command such as
+** COPY or VACUUM or ROLLBACK.
+*/
+int sqliteAuthCommand(Parse *pParse, const char *zCmd, const char *zArg1){
+  sqlite *db = pParse->db;
+  int rc;
+  if( db->xAuth==0 ) return SQLITE_OK;
+  rc = db->xAuth(db->pAuthArg, SQLITE_COMMAND, zCmd, zArg1);
+  if( rc==SQLITE_DENY ){
+    if( zArg1 && zArg1[0] ){
+      sqliteSetString(&pParse->zErrMsg, "execution of the ", zCmd, " ", zArg1,
+          " command is prohibited", 0);
+    }else{
+      sqliteSetString(&pParse->zErrMsg, "execution of the ", zCmd,
+          " command is prohibited", 0);
+    }
+    pParse->nErr++;
+  }else if( rc!=SQLITE_OK && rc!=SQLITE_IGNORE ){
+    sqliteAuthBadReturnCode(pParse, rc);
+  }
+  return rc;
+}
+
+#endif /* SQLITE_OMIT_AUTHORIZATION */