1 files changed, 131 insertions, 0 deletions
diff --git a/test/bio_readbuffer_test.c b/test/bio_readbuffer_test.c
new file mode 100644
index 000000000000..58a03c216365
--- /dev/null
+++ b/test/bio_readbuffer_test.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/bio.h>
+#include "testutil.h"
+
+static const char *filename = NULL;
+
+/*
+ * Test that a BIO_f_readbuffer() with a BIO_new_file() behaves nicely if
+ * BIO_gets() and BIO_read_ex() are both called.
+ * Since the BIO_gets() calls buffer the reads, the BIO_read_ex() should
+ * still be able to read the buffered data if we seek back to the start.
+ *
+ * The following cases are tested using tstid:
+ * 0 : Just use BIO_read_ex().
+ * 1 : Try a few reads using BIO_gets() before using BIO_read_ex()
+ * 2 : Read the entire file using BIO_gets() before using BIO_read_ex().
+ */
+static int test_readbuffer_file_bio(int tstid)
+{
+    int ret = 0, len, partial;
+    BIO *in = NULL, *in_bio = NULL, *readbuf_bio = NULL;
+    char buf[255];
+    char expected[4096];
+    size_t readbytes = 0, bytes = 0, count = 0;
+
+    /* Open a file BIO and read all the data */
+    if (!TEST_ptr(in = BIO_new_file(filename, "r"))
+        || !TEST_int_eq(BIO_read_ex(in, expected, sizeof(expected),
+                                    &readbytes), 1)
+        || !TEST_int_lt(readbytes, sizeof(expected)))
+        goto err;
+    BIO_free(in);
+    in = NULL;
+
+    /* Create a new file bio that sits under a readbuffer BIO */
+    if (!TEST_ptr(readbuf_bio = BIO_new(BIO_f_readbuffer()))
+        || !TEST_ptr(in_bio = BIO_new_file(filename, "r")))
+        goto err;
+
+    in_bio = BIO_push(readbuf_bio, in_bio);
+    readbuf_bio = NULL;
+
+    if (!TEST_int_eq(BIO_tell(in_bio), 0))
+        goto err;
+
+    if (tstid != 0) {
+        partial = 4;
+        while (!BIO_eof(in_bio)) {
+            len = BIO_gets(in_bio, buf, sizeof(buf));
+            if (len == 0) {
+                if (!TEST_true(BIO_eof(in_bio)))
+                    goto err;
+            } else {
+                if (!TEST_int_gt(len, 0)
+                    || !TEST_int_le(len, (int)sizeof(buf) - 1))
+                    goto err;
+                if (!TEST_true(buf[len] == 0))
+                    goto err;
+                if (len > 1
+                    && !BIO_eof(in_bio)
+                    && len != ((int)sizeof(buf) - 1)
+                    && !TEST_true(buf[len - 1] == '\n'))
+                    goto err;
+            }
+            if (tstid == 1 && --partial == 0)
+                break;
+        }
+    }
+    if (!TEST_int_eq(BIO_seek(in_bio, 0), 1))
+        goto err;
+
+    len = 8; /* Do a small partial read to start with */
+    while (!BIO_eof(in_bio)) {
+        if (!TEST_int_eq(BIO_read_ex(in_bio, buf, len, &bytes), 1))
+            break;
+        if (!TEST_mem_eq(buf, bytes, expected + count, bytes))
+            goto err;
+        count += bytes;
+        len = sizeof(buf); /* fill the buffer on subsequent reads */
+    }
+    if (!TEST_int_eq(count, readbytes))
+        goto err;
+    ret = 1;
+err:
+    BIO_free(in);
+    BIO_free_all(in_bio);
+    BIO_free(readbuf_bio);
+    return ret;
+}
+
+typedef enum OPTION_choice {
+    OPT_ERR = -1,
+    OPT_EOF = 0,
+    OPT_TEST_ENUM
+} OPTION_CHOICE;
+
+const OPTIONS *test_get_options(void)
+{
+    static const OPTIONS test_options[] = {
+        OPT_TEST_OPTIONS_WITH_EXTRA_USAGE("file\n"),
+        { OPT_HELP_STR, 1, '-', "file\tFile to run tests on.\n" },
+        { NULL }
+    };
+    return test_options;
+}
+
+int setup_tests(void)
+{
+    OPTION_CHOICE o;
+
+    while ((o = opt_next()) != OPT_EOF) {
+        switch (o) {
+        case OPT_TEST_CASES:
+            break;
+        default:
+            return 0;
+        }
+    }
+    filename = test_get_argument(0);
+
+    ADD_ALL_TESTS(test_readbuffer_file_bio, 3);
+    return 1;
+}