set the error state from the codec when the plaintext_header_size is invalid

sjlombardo · sjlombardo · commit ba14070de119 · 2020-12-01T10:52:34.000-05:00
diff --git a/src/crypto.c b/src/crypto.c
@@ -330,8 +330,9 @@ int sqlcipher_codec_pragma(sqlite3* db, int iDb, Parse *pParse, const char *zLef
     if(ctx) {
       if( zRight ) {
         int size = atoi(zRight);
-        if((rc = sqlcipher_codec_ctx_set_plaintext_header_size(ctx, size)) != SQLITE_OK)
-          sqlcipher_codec_ctx_set_error(ctx, SQLITE_ERROR); 
+        /* deliberately ignore result code, if size is invalid it will be set to -1
+           and trip the error later in the codec */
+        sqlcipher_codec_ctx_set_plaintext_header_size(ctx, size);
       } else {
         char *size = sqlite3_mprintf("%d", sqlcipher_codec_ctx_get_plaintext_header_size(ctx));
         codec_vdbe_return_string(pParse, "cipher_plaintext_header_size", size, P4_DYNAMIC);
@@ -697,6 +698,14 @@ static void* sqlite3Codec(void *iCtx, void *data, Pgno pgno, int mode) {
    return NULL;
   }
 
+  /* if the plaintext_header_size is negative that means an invalid size was set via 
+     PRAGMA. We can't set the error state on the pager at that point because the pager
+     may not be open yet. However, this is a fatal error state, so abort the codec */
+  if(plaintext_header_sz < 0) {
+    sqlcipher_codec_ctx_set_error(ctx, SQLITE_ERROR);
+    return NULL;
+  }
+
   if(pgno == 1) /* adjust starting pointers in data page for header offset on first page*/   
     offset = plaintext_header_sz ? plaintext_header_sz : FILE_HEADER_SZ; 
   
diff --git a/src/crypto_impl.c b/src/crypto_impl.c
@@ -665,6 +665,7 @@ int sqlcipher_codec_ctx_set_plaintext_header_size(codec_ctx *ctx, int size) {
     ctx->plaintext_header_sz = size;
     return SQLITE_OK;
   }
+  ctx->plaintext_header_sz = -1;
   return SQLITE_ERROR;
 } 
 
diff --git a/test/sqlcipher-plaintext-header.test b/test/sqlcipher-plaintext-header.test
@@ -183,7 +183,7 @@ do_test test-invalid-plaintext-header-sizes {
     PRAGMA cipher_plaintext_header_size = 24; 
     CREATE TABLE t1(a,b);
   "]
-} {{1 {SQL logic error}} {1 {SQL logic error}} {1 {SQL logic error}}}
+} {{1 {out of memory}} {1 {out of memory}} {1 {out of memory}}}
 db close
 file delete -force test.db
 

Original file line number	Diff line number	Diff line change
`@@ -665,6 +665,7 @@ int sqlcipher_codec_ctx_set_plaintext_header_size(codec_ctx *ctx, int size) {`
`665`	`665`	`ctx->plaintext_header_sz = size;`
`666`	`666`	`return SQLITE_OK;`
`667`	`667`	`}`
	`668`	`+ ctx->plaintext_header_sz = -1;`
`668`	`669`	`return SQLITE_ERROR;`
`669`	`670`	`}`
`670`	`671`