Add support for attaching databases with non-default page sizes

developernotes · developernotes · commit a31d65d7c8b2 · 2015-01-29T10:39:12.000-06:00
diff --git a/src/crypto.c b/src/crypto.c
@@ -186,6 +186,15 @@ int sqlcipher_codec_pragma(sqlite3* db, int iDb, Parse *pParse, const char *zLef
       }
     }
   }else
+  if( sqlite3StrICmp(zLeft,"cipher_default_page_size")==0 ){
+    if( zRight ) {
+      sqlcipher_set_default_pagesize(atoi(zRight));
+    } else {
+      char *default_page_size = sqlite3_mprintf("%d", sqlcipher_get_default_pagesize());
+      codec_vdbe_return_static_string(pParse, "cipher_default_page_size", default_page_size);
+      sqlite3_free(default_page_size);
+    }
+  }else
   if( sqlite3StrICmp(zLeft,"cipher_default_use_hmac")==0 ){
     if( zRight ) {
       sqlcipher_set_default_use_hmac(sqlite3GetBoolean(zRight,1));
diff --git a/src/crypto.h b/src/crypto.h
@@ -180,6 +180,9 @@ int sqlcipher_codec_ctx_set_pagesize(codec_ctx *, int);
 int sqlcipher_codec_ctx_get_pagesize(codec_ctx *);
 int sqlcipher_codec_ctx_get_reservesize(codec_ctx *);
 
+void sqlcipher_set_default_pagesize(int page_size);
+int sqlcipher_get_default_pagesize();
+
 void sqlcipher_set_default_kdf_iter(int iter);
 int sqlcipher_get_default_kdf_iter();
 
diff --git a/src/crypto_impl.c b/src/crypto_impl.c
@@ -70,6 +70,7 @@ typedef struct {
 static unsigned int default_flags = DEFAULT_CIPHER_FLAGS;
 static unsigned char hmac_salt_mask = HMAC_SALT_MASK;
 static int default_kdf_iter = PBKDF2_ITER;
+static int default_page_size = SQLITE_DEFAULT_PAGE_SIZE;
 static unsigned int sqlcipher_activate_count = 0;
 static sqlite3_mutex* sqlcipher_provider_mutex = NULL;
 static sqlcipher_provider *default_provider = NULL;
@@ -661,6 +662,14 @@ int sqlcipher_codec_ctx_get_pagesize(codec_ctx *ctx) {
   return ctx->page_sz;
 }
 
+void sqlcipher_set_default_pagesize(int page_size) {
+  default_page_size = page_size;
+}
+
+int sqlcipher_get_default_pagesize() {
+  return default_page_size;
+}
+
 int sqlcipher_codec_ctx_init(codec_ctx **iCtx, Db *pDb, Pager *pPager, sqlite3_file *fd, const void *zKey, int nKey) {
   int rc;
   codec_ctx *ctx;
@@ -691,7 +700,7 @@ int sqlcipher_codec_ctx_init(codec_ctx **iCtx, Db *pDb, Pager *pPager, sqlite3_f
      in encrypted and thus sqlite can't effectively determine the pagesize. this causes an issue in 
      cases where bytes 16 & 17 of the page header are a power of 2 as reported by John Lehman
   */
-  if((rc = sqlcipher_codec_ctx_set_pagesize(ctx, SQLITE_DEFAULT_PAGE_SIZE)) != SQLITE_OK) return rc;
+  if((rc = sqlcipher_codec_ctx_set_pagesize(ctx, default_page_size)) != SQLITE_OK) return rc;
 
   if((rc = sqlcipher_cipher_ctx_init(&ctx->read_ctx)) != SQLITE_OK) return rc; 
   if((rc = sqlcipher_cipher_ctx_init(&ctx->write_ctx)) != SQLITE_OK) return rc; 
diff --git a/test/crypto.test b/test/crypto.test
@@ -2256,5 +2256,27 @@ do_test can-migrate-with-raw-hex-key {
 db close
 file delete -force test.db
 
+do_test attach_database_with_non_default_page_size {
+    sqlite_orig db test2.db
+    execsql {
+        PRAGMA key = 'test';
+        PRAGMA cipher_page_size = 4096;
+        CREATE TABLE t1(a,b);
+        INSERT INTO t1(a,b) values('one for the money', 'two for the show');
+        INSERT INTO t1(a,b) values('three to get ready', 'now, go cat, go');
+    }
+    db close
+
+    sqlite_orig db test.db
+    execsql {
+        PRAGMA cipher_default_page_size = 4096;
+        PRAGMA key = 'test';
+        ATTACH DATABASE 'test2.db' as test2 KEY 'test';
+        SELECT count(*) FROM test2.t1;
+    }
+} {2}
+db close
+file delete -force test.db test2.db
+
 sqlite3_test_control_pending_byte $old_pending_byte
 finish_test
