openssl/test/danetest.c
Viktor Dukhovni 5ae4ceb92c Perform DANE-EE(3) name checks by default
In light of potential UKS (unknown key share) attacks on some
applications, primarily browsers, despite RFC761, name checks are
by default applied with DANE-EE(3) TLSA records.  Applications for
which UKS is not a problem can optionally disable DANE-EE(3) name
checks via the new SSL_CTX_dane_set_flags() and friends.

Reviewed-by: Rich Salz <rsalz@openssl.org>
2016-07-12 10:16:34 -04:00

504 lines
13 KiB
C

/*
* Copyright 2015-2016 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 <stdio.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>
#include <errno.h>
#include <openssl/crypto.h>
#include <openssl/evp.h>
#include <openssl/x509.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/conf.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif
#include "../e_os.h"
#define _UC(c) ((unsigned char)(c))
static const char *progname;
/*
* Forward declaration, of function that uses internal interfaces, from headers
* included at the end of this module.
*/
static void store_ctx_dane_init(X509_STORE_CTX *, SSL *);
static int saved_errno;
static void save_errno(void)
{
saved_errno = errno;
}
static int restore_errno(void)
{
int ret = errno;
errno = saved_errno;
return ret;
}
static void test_usage(void)
{
fprintf(stderr, "usage: %s: danetest basedomain CAfile tlsafile\n", progname);
}
static void print_errors(void)
{
unsigned long err;
char buffer[1024];
const char *file;
const char *data;
int line;
int flags;
while ((err = ERR_get_error_line_data(&file, &line, &data, &flags)) != 0) {
ERR_error_string_n(err, buffer, sizeof(buffer));
if (flags & ERR_TXT_STRING)
fprintf(stderr, "Error: %s:%s:%d:%s\n", buffer, file, line, data);
else
fprintf(stderr, "Error: %s:%s:%d\n", buffer, file, line);
}
}
static int verify_chain(SSL *ssl, STACK_OF(X509) *chain)
{
int ret = -1;
X509_STORE_CTX *store_ctx;
SSL_CTX *ssl_ctx = SSL_get_SSL_CTX(ssl);
X509_STORE *store = SSL_CTX_get_cert_store(ssl_ctx);
int store_ctx_idx = SSL_get_ex_data_X509_STORE_CTX_idx();
X509 *cert = sk_X509_value(chain, 0);
if ((store_ctx = X509_STORE_CTX_new()) == NULL)
return -1;
if (!X509_STORE_CTX_init(store_ctx, store, cert, chain))
goto end;
if (!X509_STORE_CTX_set_ex_data(store_ctx, store_ctx_idx, ssl))
goto end;
X509_STORE_CTX_set_default(store_ctx,
SSL_is_server(ssl) ? "ssl_client" : "ssl_server");
X509_VERIFY_PARAM_set1(X509_STORE_CTX_get0_param(store_ctx),
SSL_get0_param(ssl));
store_ctx_dane_init(store_ctx, ssl);
if (SSL_get_verify_callback(ssl))
X509_STORE_CTX_set_verify_cb(store_ctx, SSL_get_verify_callback(ssl));
ret = X509_verify_cert(store_ctx);
SSL_set_verify_result(ssl, X509_STORE_CTX_get_error(store_ctx));
X509_STORE_CTX_cleanup(store_ctx);
end:
X509_STORE_CTX_free(store_ctx);
return (ret);
}
static STACK_OF(X509) *load_chain(BIO *fp, int nelem)
{
int count;
char *name = 0;
char *header = 0;
unsigned char *data = 0;
long len;
char *errtype = 0; /* if error: cert or pkey? */
STACK_OF(X509) *chain;
typedef X509 *(*d2i_X509_t)(X509 **, const unsigned char **, long);
if ((chain = sk_X509_new_null()) == 0) {
perror("malloc");
exit(1);
}
for (count = 0;
count < nelem && errtype == 0
&& PEM_read_bio(fp, &name, &header, &data, &len);
++count) {
const unsigned char *p = data;
if (strcmp(name, PEM_STRING_X509) == 0
|| strcmp(name, PEM_STRING_X509_TRUSTED) == 0
|| strcmp(name, PEM_STRING_X509_OLD) == 0) {
d2i_X509_t d = strcmp(name, PEM_STRING_X509_TRUSTED) ?
d2i_X509_AUX : d2i_X509;
X509 *cert = d(0, &p, len);
if (cert == 0 || (p - data) != len)
errtype = "certificate";
else if (sk_X509_push(chain, cert) == 0) {
perror("malloc");
goto err;
}
} else {
fprintf(stderr, "unexpected chain file object: %s\n", name);
goto err;
}
/*
* If any of these were null, PEM_read() would have failed.
*/
OPENSSL_free(name);
OPENSSL_free(header);
OPENSSL_free(data);
}
if (errtype) {
fprintf(stderr, "error reading: malformed %s\n", errtype);
goto err;
}
if (count == nelem) {
ERR_clear_error();
return chain;
}
err:
/* Some other PEM read error */
sk_X509_pop_free(chain, X509_free);
print_errors();
return NULL;
}
static char *read_to_eol(BIO *f)
{
static char buf[1024];
int n;
if (!BIO_gets(f, buf, sizeof(buf)))
return NULL;
n = strlen(buf);
if (buf[n-1] != '\n') {
if (n+1 == sizeof(buf)) {
fprintf(stderr, "%s: warning: input too long\n", progname);
} else {
fprintf(stderr, "%s: warning: EOF before newline\n", progname);
}
return NULL;
}
/* Trim trailing whitespace */
while (n > 0 && isspace(_UC(buf[n-1])))
buf[--n] = '\0';
return buf;
}
/*
* Hex decoder that tolerates optional whitespace
*/
static ossl_ssize_t hexdecode(const char *in, void *result)
{
unsigned char **out = (unsigned char **)result;
unsigned char *ret = OPENSSL_malloc(strlen(in)/2);
unsigned char *cp = ret;
uint8_t byte;
int nibble = 0;
if (ret == NULL)
return -1;
for (byte = 0; *in; ++in) {
int x;
if (isspace(_UC(*in)))
continue;
x = OPENSSL_hexchar2int(*in);
if (x < 0) {
OPENSSL_free(ret);
return 0;
}
byte |= (char)x;
if ((nibble ^= 1) == 0) {
*cp++ = byte;
byte = 0;
} else {
byte <<= 4;
}
}
if (nibble != 0) {
OPENSSL_free(ret);
return 0;
}
return cp - (*out = ret);
}
static ossl_ssize_t checked_uint8(const char *in, void *out)
{
uint8_t *result = (uint8_t *)out;
const char *cp = in;
char *endp;
long v;
int e;
save_errno();
v = strtol(cp, &endp, 10);
e = restore_errno();
if (((v == LONG_MIN || v == LONG_MAX) && e == ERANGE) ||
endp == cp || !isspace(_UC(*endp)) ||
v != (*(uint8_t *)result = (uint8_t) v)) {
return -1;
}
for (cp = endp; isspace(_UC(*cp)); ++cp)
continue;
return cp - in;
}
struct tlsa_field {
void *var;
const char *name;
ossl_ssize_t (*parser)(const char *, void *);
};
static int tlsa_import_rr(SSL *ssl, const char *rrdata)
{
static uint8_t usage;
static uint8_t selector;
static uint8_t mtype;
static unsigned char *data = NULL;
static struct tlsa_field tlsa_fields[] = {
{ &usage, "usage", checked_uint8 },
{ &selector, "selector", checked_uint8 },
{ &mtype, "mtype", checked_uint8 },
{ &data, "data", hexdecode },
{ NULL, }
};
int ret;
struct tlsa_field *f;
const char *cp = rrdata;
ossl_ssize_t len = 0;
for (f = tlsa_fields; f->var; ++f) {
if ((len = f->parser(cp += len, f->var)) <= 0) {
fprintf(stderr, "%s: warning: bad TLSA %s field in: %s\n",
progname, f->name, rrdata);
return 0;
}
}
ret = SSL_dane_tlsa_add(ssl, usage, selector, mtype, data, len);
OPENSSL_free(data);
if (ret == 0) {
print_errors();
fprintf(stderr, "%s: warning: unusable TLSA rrdata: %s\n",
progname, rrdata);
return 0;
}
if (ret < 0) {
fprintf(stderr, "%s: warning: error loading TLSA rrdata: %s\n",
progname, rrdata);
return 0;
}
return ret;
}
static int allws(const char *cp)
{
while (*cp)
if (!isspace(_UC(*cp++)))
return 0;
return 1;
}
static int test_tlsafile(SSL_CTX *ctx, const char *basename,
BIO *f, const char *path)
{
char *line;
int testno = 0;
int ret = 1;
SSL *ssl;
while (ret > 0 && (line = read_to_eol(f)) != NULL) {
STACK_OF(X509) *chain;
int ntlsa;
int ncert;
int noncheck;
int want;
int want_depth;
int off;
int i;
int ok;
int err;
int mdpth;
if (*line == '\0' || *line == '#')
continue;
++testno;
if (sscanf(line, "%d %d %d %d %d%n",
&ntlsa, &ncert, &noncheck, &want, &want_depth, &off) != 5
|| !allws(line + off)) {
fprintf(stderr, "Expected tlsa count, cert count and result"
" at test %d of %s\n", testno, path);
return 0;
}
if ((ssl = SSL_new(ctx)) == NULL)
return -1;
SSL_set_connect_state(ssl);
if (SSL_dane_enable(ssl, basename) <= 0) {
SSL_free(ssl);
return -1;
}
if (noncheck)
SSL_dane_set_flags(ssl, DANE_FLAG_NO_DANE_EE_NAMECHECKS);
for (i = 0; i < ntlsa; ++i) {
if ((line = read_to_eol(f)) == NULL || !tlsa_import_rr(ssl, line)) {
SSL_free(ssl);
return 0;
}
}
/* Don't report old news */
ERR_clear_error();
chain = load_chain(f, ncert);
if (chain == NULL) {
SSL_free(ssl);
return -1;
}
ok = verify_chain(ssl, chain);
sk_X509_pop_free(chain, X509_free);
err = SSL_get_verify_result(ssl);
/*
* Peek under the hood, normally TLSA match data is hidden when
* verification fails, we can obtain any suppressed data by setting the
* verification result to X509_V_OK before looking.
*/
SSL_set_verify_result(ssl, X509_V_OK);
mdpth = SSL_get0_dane_authority(ssl, NULL, NULL);
/* Not needed any more, but lead by example and put the error back. */
SSL_set_verify_result(ssl, err);
SSL_free(ssl);
if (ok < 0) {
ret = 0;
fprintf(stderr, "verify_chain internal error in %s test %d\n",
path, testno);
print_errors();
continue;
}
if (err != want || (want == 0 && !ok)) {
ret = 0;
if (err != want) {
if (want == X509_V_OK)
fprintf(stderr, "Verification failure in %s test %d: %d: %s\n",
path, testno, err, X509_verify_cert_error_string(err));
else
fprintf(stderr, "Unexpected error in %s test %d: %d: wanted %d\n",
path, testno, err, want);
} else {
fprintf(stderr, "Verification failure in %s test %d: ok=0\n",
path, testno);
}
print_errors();
continue;
}
if (mdpth != want_depth) {
ret = 0;
fprintf(stderr, "Wrong match depth, in %s test %d: wanted %d, got: %d\n",
path, testno, want_depth, mdpth);
}
fprintf(stderr, "%s: test %d successful\n", path, testno);
}
ERR_clear_error();
return ret;
}
int main(int argc, char *argv[])
{
BIO *f;
BIO *bio_err;
SSL_CTX *ctx = NULL;
const char *basedomain;
const char *CAfile;
const char *tlsafile;
const char *p;
int ret = 1;
progname = argv[0];
if (argc != 4) {
test_usage();
EXIT(ret);
}
basedomain = argv[1];
CAfile = argv[2];
tlsafile = argv[3];
bio_err = BIO_new_fp(stderr, BIO_NOCLOSE | BIO_FP_TEXT);
p = getenv("OPENSSL_DEBUG_MEMORY");
if (p != NULL && strcmp(p, "on") == 0)
CRYPTO_set_mem_debug(1);
CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON);
f = BIO_new_file(tlsafile, "r");
if (f == NULL) {
fprintf(stderr, "%s: Error opening tlsa record file: '%s': %s\n",
progname, tlsafile, strerror(errno));
EXIT(ret);
}
ctx = SSL_CTX_new(TLS_client_method());
if (SSL_CTX_dane_enable(ctx) <= 0) {
print_errors();
goto end;
}
if (!SSL_CTX_load_verify_locations(ctx, CAfile, NULL)) {
print_errors();
goto end;
}
if ((SSL_CTX_dane_mtype_set(ctx, EVP_sha512(), 2, 1)) <= 0) {
print_errors();
goto end;
}
if ((SSL_CTX_dane_mtype_set(ctx, EVP_sha256(), 1, 2)) <= 0) {
print_errors();
goto end;
}
if (test_tlsafile(ctx, basedomain, f, tlsafile) <= 0) {
print_errors();
goto end;
}
ret = 0;
end:
BIO_free(f);
SSL_CTX_free(ctx);
#ifndef OPENSSL_NO_CRYPTO_MDEBUG
if (CRYPTO_mem_leaks(bio_err) <= 0)
ret = 1;
#endif
BIO_free(bio_err);
EXIT(ret);
}
#include <internal/dane.h>
static void store_ctx_dane_init(X509_STORE_CTX *store_ctx, SSL *ssl)
{
X509_STORE_CTX_set0_dane(store_ctx, SSL_get0_dane(ssl));
}