openssl/ssl/ssl_cert.c
Todd Short 4379d5ce78 Fix ssl_cert_set0_chain invalid pointer
When setting the certificate chain, if a certificate doesn't pass
security checks, then chain may point to a freed STACK_OF(X509)

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
2016-05-27 17:20:10 +01:00

1082 lines
30 KiB
C

/*
* Copyright 1995-2016 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
*/
/* ====================================================================
* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
* ECC cipher suite support in OpenSSL originally developed by
* SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
*/
#include <stdio.h>
#include "e_os.h"
#ifndef NO_SYS_TYPES_H
# include <sys/types.h>
#endif
#include "internal/o_dir.h"
#include <openssl/lhash.h>
#include <openssl/bio.h>
#include <openssl/pem.h>
#include <openssl/x509v3.h>
#include <openssl/dh.h>
#include <openssl/bn.h>
#include <openssl/crypto.h>
#include "ssl_locl.h"
static int ssl_security_default_callback(const SSL *s, const SSL_CTX *ctx, int op,
int bits, int nid, void *other,
void *ex);
static CRYPTO_ONCE ssl_x509_store_ctx_once = CRYPTO_ONCE_STATIC_INIT;
static volatile int ssl_x509_store_ctx_idx = -1;
static void ssl_x509_store_ctx_init(void)
{
ssl_x509_store_ctx_idx = X509_STORE_CTX_get_ex_new_index(0,
"SSL for verify callback",
NULL, NULL, NULL);
}
int SSL_get_ex_data_X509_STORE_CTX_idx(void)
{
CRYPTO_THREAD_run_once(&ssl_x509_store_ctx_once, ssl_x509_store_ctx_init);
return ssl_x509_store_ctx_idx;
}
CERT *ssl_cert_new(void)
{
CERT *ret = OPENSSL_zalloc(sizeof(*ret));
if (ret == NULL) {
SSLerr(SSL_F_SSL_CERT_NEW, ERR_R_MALLOC_FAILURE);
return NULL;
}
ret->key = &(ret->pkeys[SSL_PKEY_RSA_ENC]);
ret->references = 1;
ret->sec_cb = ssl_security_default_callback;
ret->sec_level = OPENSSL_TLS_SECURITY_LEVEL;
ret->sec_ex = NULL;
ret->lock = CRYPTO_THREAD_lock_new();
if (ret->lock == NULL) {
SSLerr(SSL_F_SSL_CERT_NEW, ERR_R_MALLOC_FAILURE);
OPENSSL_free(ret);
return NULL;
}
return ret;
}
CERT *ssl_cert_dup(CERT *cert)
{
CERT *ret = OPENSSL_zalloc(sizeof(*ret));
int i;
if (ret == NULL) {
SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
return NULL;
}
ret->references = 1;
ret->key = &ret->pkeys[cert->key - cert->pkeys];
ret->lock = CRYPTO_THREAD_lock_new();
if (ret->lock == NULL) {
SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
OPENSSL_free(ret);
return NULL;
}
#ifndef OPENSSL_NO_DH
if (cert->dh_tmp != NULL) {
ret->dh_tmp = cert->dh_tmp;
EVP_PKEY_up_ref(ret->dh_tmp);
}
ret->dh_tmp_cb = cert->dh_tmp_cb;
ret->dh_tmp_auto = cert->dh_tmp_auto;
#endif
for (i = 0; i < SSL_PKEY_NUM; i++) {
CERT_PKEY *cpk = cert->pkeys + i;
CERT_PKEY *rpk = ret->pkeys + i;
if (cpk->x509 != NULL) {
rpk->x509 = cpk->x509;
X509_up_ref(rpk->x509);
}
if (cpk->privatekey != NULL) {
rpk->privatekey = cpk->privatekey;
EVP_PKEY_up_ref(cpk->privatekey);
}
if (cpk->chain) {
rpk->chain = X509_chain_up_ref(cpk->chain);
if (!rpk->chain) {
SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
goto err;
}
}
if (cert->pkeys[i].serverinfo != NULL) {
/* Just copy everything. */
ret->pkeys[i].serverinfo =
OPENSSL_malloc(cert->pkeys[i].serverinfo_length);
if (ret->pkeys[i].serverinfo == NULL) {
SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
goto err;
}
ret->pkeys[i].serverinfo_length =
cert->pkeys[i].serverinfo_length;
memcpy(ret->pkeys[i].serverinfo,
cert->pkeys[i].serverinfo,
cert->pkeys[i].serverinfo_length);
}
}
/* Configured sigalgs copied across */
if (cert->conf_sigalgs) {
ret->conf_sigalgs = OPENSSL_malloc(cert->conf_sigalgslen);
if (ret->conf_sigalgs == NULL)
goto err;
memcpy(ret->conf_sigalgs, cert->conf_sigalgs, cert->conf_sigalgslen);
ret->conf_sigalgslen = cert->conf_sigalgslen;
} else
ret->conf_sigalgs = NULL;
if (cert->client_sigalgs) {
ret->client_sigalgs = OPENSSL_malloc(cert->client_sigalgslen);
if (ret->client_sigalgs == NULL)
goto err;
memcpy(ret->client_sigalgs, cert->client_sigalgs,
cert->client_sigalgslen);
ret->client_sigalgslen = cert->client_sigalgslen;
} else
ret->client_sigalgs = NULL;
/* Shared sigalgs also NULL */
ret->shared_sigalgs = NULL;
/* Copy any custom client certificate types */
if (cert->ctypes) {
ret->ctypes = OPENSSL_malloc(cert->ctype_num);
if (ret->ctypes == NULL)
goto err;
memcpy(ret->ctypes, cert->ctypes, cert->ctype_num);
ret->ctype_num = cert->ctype_num;
}
ret->cert_flags = cert->cert_flags;
ret->cert_cb = cert->cert_cb;
ret->cert_cb_arg = cert->cert_cb_arg;
if (cert->verify_store) {
X509_STORE_up_ref(cert->verify_store);
ret->verify_store = cert->verify_store;
}
if (cert->chain_store) {
X509_STORE_up_ref(cert->chain_store);
ret->chain_store = cert->chain_store;
}
ret->sec_cb = cert->sec_cb;
ret->sec_level = cert->sec_level;
ret->sec_ex = cert->sec_ex;
if (!custom_exts_copy(&ret->cli_ext, &cert->cli_ext))
goto err;
if (!custom_exts_copy(&ret->srv_ext, &cert->srv_ext))
goto err;
#ifndef OPENSSL_NO_PSK
if (cert->psk_identity_hint) {
ret->psk_identity_hint = OPENSSL_strdup(cert->psk_identity_hint);
if (ret->psk_identity_hint == NULL)
goto err;
}
#endif
return ret;
err:
ssl_cert_free(ret);
return NULL;
}
/* Free up and clear all certificates and chains */
void ssl_cert_clear_certs(CERT *c)
{
int i;
if (c == NULL)
return;
for (i = 0; i < SSL_PKEY_NUM; i++) {
CERT_PKEY *cpk = c->pkeys + i;
X509_free(cpk->x509);
cpk->x509 = NULL;
EVP_PKEY_free(cpk->privatekey);
cpk->privatekey = NULL;
sk_X509_pop_free(cpk->chain, X509_free);
cpk->chain = NULL;
OPENSSL_free(cpk->serverinfo);
cpk->serverinfo = NULL;
cpk->serverinfo_length = 0;
}
}
void ssl_cert_free(CERT *c)
{
int i;
if (c == NULL)
return;
CRYPTO_atomic_add(&c->references, -1, &i, c->lock);
REF_PRINT_COUNT("CERT", c);
if (i > 0)
return;
REF_ASSERT_ISNT(i < 0);
#ifndef OPENSSL_NO_DH
EVP_PKEY_free(c->dh_tmp);
#endif
ssl_cert_clear_certs(c);
OPENSSL_free(c->conf_sigalgs);
OPENSSL_free(c->client_sigalgs);
OPENSSL_free(c->shared_sigalgs);
OPENSSL_free(c->ctypes);
X509_STORE_free(c->verify_store);
X509_STORE_free(c->chain_store);
custom_exts_free(&c->cli_ext);
custom_exts_free(&c->srv_ext);
#ifndef OPENSSL_NO_PSK
OPENSSL_free(c->psk_identity_hint);
#endif
CRYPTO_THREAD_lock_free(c->lock);
OPENSSL_free(c);
}
int ssl_cert_set0_chain(SSL *s, SSL_CTX *ctx, STACK_OF(X509) *chain)
{
int i, r;
CERT_PKEY *cpk = s ? s->cert->key : ctx->cert->key;
if (!cpk)
return 0;
for (i = 0; i < sk_X509_num(chain); i++) {
r = ssl_security_cert(s, ctx, sk_X509_value(chain, i), 0, 0);
if (r != 1) {
SSLerr(SSL_F_SSL_CERT_SET0_CHAIN, r);
return 0;
}
}
sk_X509_pop_free(cpk->chain, X509_free);
cpk->chain = chain;
return 1;
}
int ssl_cert_set1_chain(SSL *s, SSL_CTX *ctx, STACK_OF(X509) *chain)
{
STACK_OF(X509) *dchain;
if (!chain)
return ssl_cert_set0_chain(s, ctx, NULL);
dchain = X509_chain_up_ref(chain);
if (!dchain)
return 0;
if (!ssl_cert_set0_chain(s, ctx, dchain)) {
sk_X509_pop_free(dchain, X509_free);
return 0;
}
return 1;
}
int ssl_cert_add0_chain_cert(SSL *s, SSL_CTX *ctx, X509 *x)
{
int r;
CERT_PKEY *cpk = s ? s->cert->key : ctx->cert->key;
if (!cpk)
return 0;
r = ssl_security_cert(s, ctx, x, 0, 0);
if (r != 1) {
SSLerr(SSL_F_SSL_CERT_ADD0_CHAIN_CERT, r);
return 0;
}
if (!cpk->chain)
cpk->chain = sk_X509_new_null();
if (!cpk->chain || !sk_X509_push(cpk->chain, x))
return 0;
return 1;
}
int ssl_cert_add1_chain_cert(SSL *s, SSL_CTX *ctx, X509 *x)
{
if (!ssl_cert_add0_chain_cert(s, ctx, x))
return 0;
X509_up_ref(x);
return 1;
}
int ssl_cert_select_current(CERT *c, X509 *x)
{
int i;
if (x == NULL)
return 0;
for (i = 0; i < SSL_PKEY_NUM; i++) {
CERT_PKEY *cpk = c->pkeys + i;
if (cpk->x509 == x && cpk->privatekey) {
c->key = cpk;
return 1;
}
}
for (i = 0; i < SSL_PKEY_NUM; i++) {
CERT_PKEY *cpk = c->pkeys + i;
if (cpk->privatekey && cpk->x509 && !X509_cmp(cpk->x509, x)) {
c->key = cpk;
return 1;
}
}
return 0;
}
int ssl_cert_set_current(CERT *c, long op)
{
int i, idx;
if (!c)
return 0;
if (op == SSL_CERT_SET_FIRST)
idx = 0;
else if (op == SSL_CERT_SET_NEXT) {
idx = (int)(c->key - c->pkeys + 1);
if (idx >= SSL_PKEY_NUM)
return 0;
} else
return 0;
for (i = idx; i < SSL_PKEY_NUM; i++) {
CERT_PKEY *cpk = c->pkeys + i;
if (cpk->x509 && cpk->privatekey) {
c->key = cpk;
return 1;
}
}
return 0;
}
void ssl_cert_set_cert_cb(CERT *c, int (*cb) (SSL *ssl, void *arg), void *arg)
{
c->cert_cb = cb;
c->cert_cb_arg = arg;
}
int ssl_verify_cert_chain(SSL *s, STACK_OF(X509) *sk)
{
X509 *x;
int i = 0;
X509_STORE *verify_store;
X509_STORE_CTX *ctx = NULL;
X509_VERIFY_PARAM *param;
if ((sk == NULL) || (sk_X509_num(sk) == 0))
return 0;
if (s->cert->verify_store)
verify_store = s->cert->verify_store;
else
verify_store = s->ctx->cert_store;
ctx = X509_STORE_CTX_new();
if (ctx == NULL) {
SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
return 0;
}
x = sk_X509_value(sk, 0);
if (!X509_STORE_CTX_init(ctx, verify_store, x, sk)) {
SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_X509_LIB);
goto end;
}
param = X509_STORE_CTX_get0_param(ctx);
/*
* XXX: Separate @AUTHSECLEVEL and @TLSSECLEVEL would be useful at some
* point, for now a single @SECLEVEL sets the same policy for TLS crypto
* and PKI authentication.
*/
X509_VERIFY_PARAM_set_auth_level(param, SSL_get_security_level(s));
/* Set suite B flags if needed */
X509_STORE_CTX_set_flags(ctx, tls1_suiteb(s));
if (!X509_STORE_CTX_set_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx(), s)) {
goto end;
}
/* Verify via DANE if enabled */
if (DANETLS_ENABLED(&s->dane))
X509_STORE_CTX_set0_dane(ctx, &s->dane);
/*
* We need to inherit the verify parameters. These can be determined by
* the context: if its a server it will verify SSL client certificates or
* vice versa.
*/
X509_STORE_CTX_set_default(ctx, s->server ? "ssl_client" : "ssl_server");
/*
* Anything non-default in "s->param" should overwrite anything in the ctx.
*/
X509_VERIFY_PARAM_set1(param, s->param);
if (s->verify_callback)
X509_STORE_CTX_set_verify_cb(ctx, s->verify_callback);
if (s->ctx->app_verify_callback != NULL)
i = s->ctx->app_verify_callback(ctx, s->ctx->app_verify_arg);
else
i = X509_verify_cert(ctx);
s->verify_result = X509_STORE_CTX_get_error(ctx);
sk_X509_pop_free(s->verified_chain, X509_free);
s->verified_chain = NULL;
if (X509_STORE_CTX_get0_chain(ctx) != NULL) {
s->verified_chain = X509_STORE_CTX_get1_chain(ctx);
if (s->verified_chain == NULL) {
SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
i = 0;
}
}
/* Move peername from the store context params to the SSL handle's */
X509_VERIFY_PARAM_move_peername(s->param, param);
end:
X509_STORE_CTX_free(ctx);
return i;
}
static void set_client_CA_list(STACK_OF(X509_NAME) **ca_list,
STACK_OF(X509_NAME) *name_list)
{
sk_X509_NAME_pop_free(*ca_list, X509_NAME_free);
*ca_list = name_list;
}
STACK_OF(X509_NAME) *SSL_dup_CA_list(STACK_OF(X509_NAME) *sk)
{
int i;
STACK_OF(X509_NAME) *ret;
X509_NAME *name;
ret = sk_X509_NAME_new_null();
for (i = 0; i < sk_X509_NAME_num(sk); i++) {
name = X509_NAME_dup(sk_X509_NAME_value(sk, i));
if ((name == NULL) || !sk_X509_NAME_push(ret, name)) {
sk_X509_NAME_pop_free(ret, X509_NAME_free);
return (NULL);
}
}
return (ret);
}
void SSL_set_client_CA_list(SSL *s, STACK_OF(X509_NAME) *name_list)
{
set_client_CA_list(&(s->client_CA), name_list);
}
void SSL_CTX_set_client_CA_list(SSL_CTX *ctx, STACK_OF(X509_NAME) *name_list)
{
set_client_CA_list(&(ctx->client_CA), name_list);
}
STACK_OF(X509_NAME) *SSL_CTX_get_client_CA_list(const SSL_CTX *ctx)
{
return (ctx->client_CA);
}
STACK_OF(X509_NAME) *SSL_get_client_CA_list(const SSL *s)
{
if (!s->server) { /* we are in the client */
if (((s->version >> 8) == SSL3_VERSION_MAJOR) && (s->s3 != NULL))
return (s->s3->tmp.ca_names);
else
return (NULL);
} else {
if (s->client_CA != NULL)
return (s->client_CA);
else
return (s->ctx->client_CA);
}
}
static int add_client_CA(STACK_OF(X509_NAME) **sk, X509 *x)
{
X509_NAME *name;
if (x == NULL)
return (0);
if ((*sk == NULL) && ((*sk = sk_X509_NAME_new_null()) == NULL))
return (0);
if ((name = X509_NAME_dup(X509_get_subject_name(x))) == NULL)
return (0);
if (!sk_X509_NAME_push(*sk, name)) {
X509_NAME_free(name);
return (0);
}
return (1);
}
int SSL_add_client_CA(SSL *ssl, X509 *x)
{
return (add_client_CA(&(ssl->client_CA), x));
}
int SSL_CTX_add_client_CA(SSL_CTX *ctx, X509 *x)
{
return (add_client_CA(&(ctx->client_CA), x));
}
static int xname_sk_cmp(const X509_NAME *const *a, const X509_NAME *const *b)
{
return (X509_NAME_cmp(*a, *b));
}
static int xname_cmp(const X509_NAME *a, const X509_NAME *b)
{
return X509_NAME_cmp(a, b);
}
static unsigned long xname_hash(const X509_NAME *a)
{
return X509_NAME_hash((X509_NAME *)a);
}
/**
* Load CA certs from a file into a ::STACK. Note that it is somewhat misnamed;
* it doesn't really have anything to do with clients (except that a common use
* for a stack of CAs is to send it to the client). Actually, it doesn't have
* much to do with CAs, either, since it will load any old cert.
* \param file the file containing one or more certs.
* \return a ::STACK containing the certs.
*/
STACK_OF(X509_NAME) *SSL_load_client_CA_file(const char *file)
{
BIO *in = BIO_new(BIO_s_file());
X509 *x = NULL;
X509_NAME *xn = NULL;
STACK_OF(X509_NAME) *ret = NULL;
LHASH_OF(X509_NAME) *name_hash =
lh_X509_NAME_new(xname_hash, xname_cmp);
if ((name_hash == NULL) || (in == NULL)) {
SSLerr(SSL_F_SSL_LOAD_CLIENT_CA_FILE, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!BIO_read_filename(in, file))
goto err;
for (;;) {
if (PEM_read_bio_X509(in, &x, NULL, NULL) == NULL)
break;
if (ret == NULL) {
ret = sk_X509_NAME_new_null();
if (ret == NULL) {
SSLerr(SSL_F_SSL_LOAD_CLIENT_CA_FILE, ERR_R_MALLOC_FAILURE);
goto err;
}
}
if ((xn = X509_get_subject_name(x)) == NULL)
goto err;
/* check for duplicates */
xn = X509_NAME_dup(xn);
if (xn == NULL)
goto err;
if (lh_X509_NAME_retrieve(name_hash, xn) != NULL) {
/* Duplicate. */
X509_NAME_free(xn);
} else {
lh_X509_NAME_insert(name_hash, xn);
sk_X509_NAME_push(ret, xn);
}
}
goto done;
err:
sk_X509_NAME_pop_free(ret, X509_NAME_free);
ret = NULL;
done:
BIO_free(in);
X509_free(x);
lh_X509_NAME_free(name_hash);
if (ret != NULL)
ERR_clear_error();
return (ret);
}
/**
* Add a file of certs to a stack.
* \param stack the stack to add to.
* \param file the file to add from. All certs in this file that are not
* already in the stack will be added.
* \return 1 for success, 0 for failure. Note that in the case of failure some
* certs may have been added to \c stack.
*/
int SSL_add_file_cert_subjects_to_stack(STACK_OF(X509_NAME) *stack,
const char *file)
{
BIO *in;
X509 *x = NULL;
X509_NAME *xn = NULL;
int ret = 1;
int (*oldcmp) (const X509_NAME *const *a, const X509_NAME *const *b);
oldcmp = sk_X509_NAME_set_cmp_func(stack, xname_sk_cmp);
in = BIO_new(BIO_s_file());
if (in == NULL) {
SSLerr(SSL_F_SSL_ADD_FILE_CERT_SUBJECTS_TO_STACK,
ERR_R_MALLOC_FAILURE);
goto err;
}
if (!BIO_read_filename(in, file))
goto err;
for (;;) {
if (PEM_read_bio_X509(in, &x, NULL, NULL) == NULL)
break;
if ((xn = X509_get_subject_name(x)) == NULL)
goto err;
xn = X509_NAME_dup(xn);
if (xn == NULL)
goto err;
if (sk_X509_NAME_find(stack, xn) >= 0)
X509_NAME_free(xn);
else
sk_X509_NAME_push(stack, xn);
}
ERR_clear_error();
goto done;
err:
ret = 0;
done:
BIO_free(in);
X509_free(x);
(void)sk_X509_NAME_set_cmp_func(stack, oldcmp);
return ret;
}
/**
* Add a directory of certs to a stack.
* \param stack the stack to append to.
* \param dir the directory to append from. All files in this directory will be
* examined as potential certs. Any that are acceptable to
* SSL_add_dir_cert_subjects_to_stack() that are not already in the stack will be
* included.
* \return 1 for success, 0 for failure. Note that in the case of failure some
* certs may have been added to \c stack.
*/
int SSL_add_dir_cert_subjects_to_stack(STACK_OF(X509_NAME) *stack,
const char *dir)
{
OPENSSL_DIR_CTX *d = NULL;
const char *filename;
int ret = 0;
/* Note that a side effect is that the CAs will be sorted by name */
while ((filename = OPENSSL_DIR_read(&d, dir))) {
char buf[1024];
int r;
if (strlen(dir) + strlen(filename) + 2 > sizeof buf) {
SSLerr(SSL_F_SSL_ADD_DIR_CERT_SUBJECTS_TO_STACK,
SSL_R_PATH_TOO_LONG);
goto err;
}
#ifdef OPENSSL_SYS_VMS
r = BIO_snprintf(buf, sizeof buf, "%s%s", dir, filename);
#else
r = BIO_snprintf(buf, sizeof buf, "%s/%s", dir, filename);
#endif
if (r <= 0 || r >= (int)sizeof(buf))
goto err;
if (!SSL_add_file_cert_subjects_to_stack(stack, buf))
goto err;
}
if (errno) {
SYSerr(SYS_F_OPENDIR, get_last_sys_error());
ERR_add_error_data(3, "OPENSSL_DIR_read(&ctx, '", dir, "')");
SSLerr(SSL_F_SSL_ADD_DIR_CERT_SUBJECTS_TO_STACK, ERR_R_SYS_LIB);
goto err;
}
ret = 1;
err:
if (d)
OPENSSL_DIR_end(&d);
return ret;
}
/* Add a certificate to a BUF_MEM structure */
static int ssl_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x)
{
int n;
unsigned char *p;
n = i2d_X509(x, NULL);
if (n < 0 || !BUF_MEM_grow_clean(buf, (int)(n + (*l) + 3))) {
SSLerr(SSL_F_SSL_ADD_CERT_TO_BUF, ERR_R_BUF_LIB);
return 0;
}
p = (unsigned char *)&(buf->data[*l]);
l2n3(n, p);
n = i2d_X509(x, &p);
if (n < 0) {
/* Shouldn't happen */
SSLerr(SSL_F_SSL_ADD_CERT_TO_BUF, ERR_R_BUF_LIB);
return 0;
}
*l += n + 3;
return 1;
}
/* Add certificate chain to internal SSL BUF_MEM structure */
int ssl_add_cert_chain(SSL *s, CERT_PKEY *cpk, unsigned long *l)
{
BUF_MEM *buf = s->init_buf;
int i, chain_count;
X509 *x;
STACK_OF(X509) *extra_certs;
STACK_OF(X509) *chain = NULL;
X509_STORE *chain_store;
/* TLSv1 sends a chain with nothing in it, instead of an alert */
if (!BUF_MEM_grow_clean(buf, 10)) {
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_BUF_LIB);
return 0;
}
if (!cpk || !cpk->x509)
return 1;
x = cpk->x509;
/*
* If we have a certificate specific chain use it, else use parent ctx.
*/
if (cpk->chain)
extra_certs = cpk->chain;
else
extra_certs = s->ctx->extra_certs;
if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || extra_certs)
chain_store = NULL;
else if (s->cert->chain_store)
chain_store = s->cert->chain_store;
else
chain_store = s->ctx->cert_store;
if (chain_store) {
X509_STORE_CTX* xs_ctx = X509_STORE_CTX_new();
if (xs_ctx == NULL) {
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
return (0);
}
if (!X509_STORE_CTX_init(xs_ctx, chain_store, x, NULL)) {
X509_STORE_CTX_free(xs_ctx);
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_X509_LIB);
return (0);
}
/*
* It is valid for the chain not to be complete (because normally we
* don't include the root cert in the chain). Therefore we deliberately
* ignore the error return from this call. We're not actually verifying
* the cert - we're just building as much of the chain as we can
*/
(void) X509_verify_cert(xs_ctx);
/* Don't leave errors in the queue */
ERR_clear_error();
chain = X509_STORE_CTX_get0_chain(xs_ctx);
i = ssl_security_cert_chain(s, chain, NULL, 0);
if (i != 1) {
#if 0
/* Dummy error calls so mkerr generates them */
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_EE_KEY_TOO_SMALL);
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_KEY_TOO_SMALL);
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_MD_TOO_WEAK);
#endif
X509_STORE_CTX_free(xs_ctx);
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i);
return 0;
}
chain_count = sk_X509_num(chain);
for (i = 0; i < chain_count; i++) {
x = sk_X509_value(chain, i);
if (!ssl_add_cert_to_buf(buf, l, x)) {
X509_STORE_CTX_free(xs_ctx);
return 0;
}
}
X509_STORE_CTX_free(xs_ctx);
} else {
i = ssl_security_cert_chain(s, extra_certs, x, 0);
if (i != 1) {
SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i);
return 0;
}
if (!ssl_add_cert_to_buf(buf, l, x))
return 0;
for (i = 0; i < sk_X509_num(extra_certs); i++) {
x = sk_X509_value(extra_certs, i);
if (!ssl_add_cert_to_buf(buf, l, x))
return 0;
}
}
return 1;
}
/* Build a certificate chain for current certificate */
int ssl_build_cert_chain(SSL *s, SSL_CTX *ctx, int flags)
{
CERT *c = s ? s->cert : ctx->cert;
CERT_PKEY *cpk = c->key;
X509_STORE *chain_store = NULL;
X509_STORE_CTX *xs_ctx = NULL;
STACK_OF(X509) *chain = NULL, *untrusted = NULL;
X509 *x;
int i, rv = 0;
unsigned long error;
if (!cpk->x509) {
SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, SSL_R_NO_CERTIFICATE_SET);
goto err;
}
/* Rearranging and check the chain: add everything to a store */
if (flags & SSL_BUILD_CHAIN_FLAG_CHECK) {
chain_store = X509_STORE_new();
if (chain_store == NULL)
goto err;
for (i = 0; i < sk_X509_num(cpk->chain); i++) {
x = sk_X509_value(cpk->chain, i);
if (!X509_STORE_add_cert(chain_store, x)) {
error = ERR_peek_last_error();
if (ERR_GET_LIB(error) != ERR_LIB_X509 ||
ERR_GET_REASON(error) !=
X509_R_CERT_ALREADY_IN_HASH_TABLE)
goto err;
ERR_clear_error();
}
}
/* Add EE cert too: it might be self signed */
if (!X509_STORE_add_cert(chain_store, cpk->x509)) {
error = ERR_peek_last_error();
if (ERR_GET_LIB(error) != ERR_LIB_X509 ||
ERR_GET_REASON(error) != X509_R_CERT_ALREADY_IN_HASH_TABLE)
goto err;
ERR_clear_error();
}
} else {
if (c->chain_store)
chain_store = c->chain_store;
else if (s)
chain_store = s->ctx->cert_store;
else
chain_store = ctx->cert_store;
if (flags & SSL_BUILD_CHAIN_FLAG_UNTRUSTED)
untrusted = cpk->chain;
}
xs_ctx = X509_STORE_CTX_new();
if (xs_ctx == NULL) {
SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!X509_STORE_CTX_init(xs_ctx, chain_store, cpk->x509, untrusted)) {
SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, ERR_R_X509_LIB);
goto err;
}
/* Set suite B flags if needed */
X509_STORE_CTX_set_flags(xs_ctx,
c->cert_flags & SSL_CERT_FLAG_SUITEB_128_LOS);
i = X509_verify_cert(xs_ctx);
if (i <= 0 && flags & SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR) {
if (flags & SSL_BUILD_CHAIN_FLAG_CLEAR_ERROR)
ERR_clear_error();
i = 1;
rv = 2;
}
if (i > 0)
chain = X509_STORE_CTX_get1_chain(xs_ctx);
if (i <= 0) {
SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, SSL_R_CERTIFICATE_VERIFY_FAILED);
i = X509_STORE_CTX_get_error(xs_ctx);
ERR_add_error_data(2, "Verify error:",
X509_verify_cert_error_string(i));
goto err;
}
/* Remove EE certificate from chain */
x = sk_X509_shift(chain);
X509_free(x);
if (flags & SSL_BUILD_CHAIN_FLAG_NO_ROOT) {
if (sk_X509_num(chain) > 0) {
/* See if last cert is self signed */
x = sk_X509_value(chain, sk_X509_num(chain) - 1);
if (X509_get_extension_flags(x) & EXFLAG_SS) {
x = sk_X509_pop(chain);
X509_free(x);
}
}
}
/*
* Check security level of all CA certificates: EE will have been checked
* already.
*/
for (i = 0; i < sk_X509_num(chain); i++) {
x = sk_X509_value(chain, i);
rv = ssl_security_cert(s, ctx, x, 0, 0);
if (rv != 1) {
SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, rv);
sk_X509_pop_free(chain, X509_free);
rv = 0;
goto err;
}
}
sk_X509_pop_free(cpk->chain, X509_free);
cpk->chain = chain;
if (rv == 0)
rv = 1;
err:
if (flags & SSL_BUILD_CHAIN_FLAG_CHECK)
X509_STORE_free(chain_store);
X509_STORE_CTX_free(xs_ctx);
return rv;
}
int ssl_cert_set_cert_store(CERT *c, X509_STORE *store, int chain, int ref)
{
X509_STORE **pstore;
if (chain)
pstore = &c->chain_store;
else
pstore = &c->verify_store;
X509_STORE_free(*pstore);
*pstore = store;
if (ref && store)
X509_STORE_up_ref(store);
return 1;
}
static int ssl_security_default_callback(const SSL *s, const SSL_CTX *ctx, int op,
int bits, int nid, void *other,
void *ex)
{
int level, minbits;
static const int minbits_table[5] = { 80, 112, 128, 192, 256 };
if (ctx)
level = SSL_CTX_get_security_level(ctx);
else
level = SSL_get_security_level(s);
if (level <= 0) {
/*
* No EDH keys weaker than 1024-bits even at level 0, otherwise,
* anything goes.
*/
if (op == SSL_SECOP_TMP_DH && bits < 80)
return 0;
return 1;
}
if (level > 5)
level = 5;
minbits = minbits_table[level - 1];
switch (op) {
case SSL_SECOP_CIPHER_SUPPORTED:
case SSL_SECOP_CIPHER_SHARED:
case SSL_SECOP_CIPHER_CHECK:
{
const SSL_CIPHER *c = other;
/* No ciphers below security level */
if (bits < minbits)
return 0;
/* No unauthenticated ciphersuites */
if (c->algorithm_auth & SSL_aNULL)
return 0;
/* No MD5 mac ciphersuites */
if (c->algorithm_mac & SSL_MD5)
return 0;
/* SHA1 HMAC is 160 bits of security */
if (minbits > 160 && c->algorithm_mac & SSL_SHA1)
return 0;
/* Level 2: no RC4 */
if (level >= 2 && c->algorithm_enc == SSL_RC4)
return 0;
/* Level 3: forward secure ciphersuites only */
if (level >= 3 && !(c->algorithm_mkey & (SSL_kEDH | SSL_kEECDH)))
return 0;
break;
}
case SSL_SECOP_VERSION:
if (!SSL_IS_DTLS(s)) {
/* SSLv3 not allowed at level 2 */
if (nid <= SSL3_VERSION && level >= 2)
return 0;
/* TLS v1.1 and above only for level 3 */
if (nid <= TLS1_VERSION && level >= 3)
return 0;
/* TLS v1.2 only for level 4 and above */
if (nid <= TLS1_1_VERSION && level >= 4)
return 0;
} else {
/* DTLS v1.2 only for level 4 and above */
if (DTLS_VERSION_LT(nid, DTLS1_2_VERSION) && level >= 4)
return 0;
}
break;
case SSL_SECOP_COMPRESSION:
if (level >= 2)
return 0;
break;
case SSL_SECOP_TICKET:
if (level >= 3)
return 0;
break;
default:
if (bits < minbits)
return 0;
}
return 1;
}
int ssl_security(const SSL *s, int op, int bits, int nid, void *other)
{
return s->cert->sec_cb(s, NULL, op, bits, nid, other, s->cert->sec_ex);
}
int ssl_ctx_security(const SSL_CTX *ctx, int op, int bits, int nid, void *other)
{
return ctx->cert->sec_cb(NULL, ctx, op, bits, nid, other,
ctx->cert->sec_ex);
}