/*

 * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (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 <string.h>

#include "ssltestlib.h"

#include "testutil.h"

static int docorrupt = 0;

static void copy_flags(BIO *bio)

{

    int flags;

    BIO *next = BIO_next(bio);

    flags = BIO_test_flags(next, BIO_FLAGS_SHOULD_RETRY | BIO_FLAGS_RWS);

    BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY | BIO_FLAGS_RWS);

    BIO_set_flags(bio, flags);

}

static int tls_corrupt_read(BIO *bio, char *out, int outl)

{

    int ret;

    BIO *next = BIO_next(bio);

    ret = BIO_read(next, out, outl);

    copy_flags(bio);

    return ret;

}

static int tls_corrupt_write(BIO *bio, const char *in, int inl)

{

    int ret;

    BIO *next = BIO_next(bio);

    char *copy;

    if (docorrupt) {

        if (!TEST_ptr(copy = BUF_memdup(in, inl)))

            return 0;

        /* corrupt last bit of application data */

        copy[inl-1] ^= 1;

        ret = BIO_write(next, copy, inl);

        OPENSSL_free(copy);

    } else {

        ret = BIO_write(next, in, inl);

    }

    copy_flags(bio);

    return ret;

}

static long tls_corrupt_ctrl(BIO *bio, int cmd, long num, void *ptr)

{

    long ret;

    BIO *next = BIO_next(bio);

    if (next == NULL)

        return 0;

    switch (cmd) {

    case BIO_CTRL_DUP:

        ret = 0L;

        break;

    default:

        ret = BIO_ctrl(next, cmd, num, ptr);

        break;

    }

    return ret;

}

static int tls_corrupt_gets(BIO *bio, char *buf, int size)

{

    /* We don't support this - not needed anyway */

    return -1;

}

static int tls_corrupt_puts(BIO *bio, const char *str)

{

    /* We don't support this - not needed anyway */

    return -1;

}

static int tls_corrupt_new(BIO *bio)

{

    BIO_set_init(bio, 1);

    return 1;

}

static int tls_corrupt_free(BIO *bio)

{

    BIO_set_init(bio, 0);

    return 1;

}

#define BIO_TYPE_CUSTOM_FILTER  (0x80 | BIO_TYPE_FILTER)

static BIO_METHOD *method_tls_corrupt = NULL;

/* Note: Not thread safe! */

static const BIO_METHOD *bio_f_tls_corrupt_filter(void)

{

    if (method_tls_corrupt == NULL) {

        method_tls_corrupt = BIO_meth_new(BIO_TYPE_CUSTOM_FILTER,

                                          "TLS corrupt filter");

        if (   method_tls_corrupt == NULL

            || !BIO_meth_set_write(method_tls_corrupt, tls_corrupt_write)

            || !BIO_meth_set_read(method_tls_corrupt, tls_corrupt_read)

            || !BIO_meth_set_puts(method_tls_corrupt, tls_corrupt_puts)

            || !BIO_meth_set_gets(method_tls_corrupt, tls_corrupt_gets)

            || !BIO_meth_set_ctrl(method_tls_corrupt, tls_corrupt_ctrl)

            || !BIO_meth_set_create(method_tls_corrupt, tls_corrupt_new)

            || !BIO_meth_set_destroy(method_tls_corrupt, tls_corrupt_free))

            return NULL;

    }

    return method_tls_corrupt;

}

static void bio_f_tls_corrupt_filter_free(void)

{

    BIO_meth_free(method_tls_corrupt);

}

/*

 * The test is supposed to be executed with RSA key, customarily

 * with apps/server.pem used even in other tests. For this reason

 * |cipher_list| is initialized with RSA ciphers' names. This

 * naturally means that if test is to be re-purposed for other

 * type of key, then NID_auth_* filter below would need adjustment.

 */

static const char **cipher_list = NULL;

static int setup_cipher_list(void)

{

    SSL_CTX *ctx = NULL;

    SSL *ssl = NULL;

    STACK_OF(SSL_CIPHER) *sk_ciphers = NULL;

    int i, j, numciphers = 0;

    if (!TEST_ptr(ctx = SSL_CTX_new(TLS_server_method()))

            || !TEST_ptr(ssl = SSL_new(ctx))

            || !TEST_ptr(sk_ciphers = SSL_get1_supported_ciphers(ssl)))

        goto err;

    /*

     * The |cipher_list| will be filled only with names of RSA ciphers,

     * so that some of the allocated space will be wasted, but the loss

     * is deemed acceptable...

     */

    cipher_list = OPENSSL_malloc(sk_SSL_CIPHER_num(sk_ciphers) *

                                 sizeof(cipher_list[0]));

    if (!TEST_ptr(cipher_list))

        goto err;

    for (j = 0, i = 0; i < sk_SSL_CIPHER_num(sk_ciphers); i++) {

        const SSL_CIPHER *cipher = sk_SSL_CIPHER_value(sk_ciphers, i);

        if (SSL_CIPHER_get_auth_nid(cipher) == NID_auth_rsa)

            cipher_list[j++] = SSL_CIPHER_get_name(cipher);

    }

    if (TEST_int_ne(j, 0))

        numciphers = j;

err:

    sk_SSL_CIPHER_free(sk_ciphers);

    SSL_free(ssl);

    SSL_CTX_free(ctx);

    return numciphers;

}

static char *cert = NULL;

static char *privkey = NULL;

static int test_ssl_corrupt(int testidx)

{

    static unsigned char junk[16000] = { 0 };

    SSL_CTX *sctx = NULL, *cctx = NULL;

    SSL *server = NULL, *client = NULL;

    BIO *c_to_s_fbio;

    int testresult = 0;

    STACK_OF(SSL_CIPHER) *ciphers;

    const SSL_CIPHER *currcipher;

    docorrupt = 0;

    TEST_info("Starting #%d, %s", testidx, cipher_list[testidx]);

    if (!TEST_true(create_ssl_ctx_pair(TLS_server_method(), TLS_client_method(),

                                       TLS1_VERSION, TLS_MAX_VERSION,

                                       &sctx, &cctx, cert, privkey)))

        return 0;

    if (!TEST_true(SSL_CTX_set_cipher_list(cctx, cipher_list[testidx]))

            || !TEST_true(SSL_CTX_set_ciphersuites(cctx, ""))

            || !TEST_ptr(ciphers = SSL_CTX_get_ciphers(cctx))

            || !TEST_int_eq(sk_SSL_CIPHER_num(ciphers), 1)

            || !TEST_ptr(currcipher = sk_SSL_CIPHER_value(ciphers, 0)))

        goto end;

    /*

     * No ciphers we are using are TLSv1.3 compatible so we should not attempt

     * to negotiate TLSv1.3

     */

    if (!TEST_true(SSL_CTX_set_max_proto_version(cctx, TLS1_2_VERSION)))

        goto end;

    if (!TEST_ptr(c_to_s_fbio = BIO_new(bio_f_tls_corrupt_filter())))

        goto end;

    /* BIO is freed by create_ssl_connection on error */

    if (!TEST_true(create_ssl_objects(sctx, cctx, &server, &client, NULL,

                                      c_to_s_fbio)))

        goto end;

    if (!TEST_true(create_ssl_connection(server, client, SSL_ERROR_NONE)))

        goto end;

    docorrupt = 1;

    if (!TEST_int_ge(SSL_write(client, junk, sizeof(junk)), 0))

        goto end;

    if (!TEST_int_lt(SSL_read(server, junk, sizeof(junk)), 0))

        goto end;

    if (!TEST_int_eq(ERR_GET_REASON(ERR_peek_error()),

                     SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC))

        goto end;

    testresult = 1;

 end:

    SSL_free(server);

    SSL_free(client);

    SSL_CTX_free(sctx);

    SSL_CTX_free(cctx);

    return testresult;

}

int setup_tests(void)

{

    int n;

    if (!TEST_ptr(cert = test_get_argument(0))

            || !TEST_ptr(privkey = test_get_argument(1))) {

        TEST_note("Usage error: require cert and private key files");

        return 0;

    }

    n = setup_cipher_list();

    if (n > 0)

        ADD_ALL_TESTS(test_ssl_corrupt, n);

    return 1;

}

void cleanup_tests(void)

{

    bio_f_tls_corrupt_filter_free();

    OPENSSL_free(cipher_list);

}