SSL: session id context now includes certificate hash.

This prevents inappropriate session reuse in unrelated server{}
blocks, while preserving ability to restore sessions on other servers
when using TLS Session Tickets.

Additionally, session context is now set even if there is no session cache
configured.  This is needed as it's also used for TLS Session Tickets.

Thanks to Antoine Delignat-Lavaud and Piotr Sikora.
This commit is contained in:
Maxim Dounin 2014-09-15 17:59:47 +04:00
parent 2cdbe76ad4
commit bf23016157
1 changed files with 96 additions and 2 deletions

View File

@ -27,6 +27,8 @@ static void ngx_ssl_connection_error(ngx_connection_t *c, int sslerr,
ngx_err_t err, char *text);
static void ngx_ssl_clear_error(ngx_log_t *log);
static ngx_int_t ngx_ssl_session_id_context(ngx_ssl_t *ssl,
ngx_str_t *sess_ctx);
ngx_int_t ngx_ssl_session_cache_init(ngx_shm_zone_t *shm_zone, void *data);
static int ngx_ssl_new_session(ngx_ssl_conn_t *ssl_conn,
ngx_ssl_session_t *sess);
@ -1729,13 +1731,15 @@ ngx_ssl_session_cache(ngx_ssl_t *ssl, ngx_str_t *sess_ctx,
SSL_CTX_set_timeout(ssl->ctx, (long) timeout);
if (ngx_ssl_session_id_context(ssl, sess_ctx) != NGX_OK) {
return NGX_ERROR;
}
if (builtin_session_cache == NGX_SSL_NO_SCACHE) {
SSL_CTX_set_session_cache_mode(ssl->ctx, SSL_SESS_CACHE_OFF);
return NGX_OK;
}
SSL_CTX_set_session_id_context(ssl->ctx, sess_ctx->data, sess_ctx->len);
if (builtin_session_cache == NGX_SSL_NONE_SCACHE) {
/*
@ -1792,6 +1796,96 @@ ngx_ssl_session_cache(ngx_ssl_t *ssl, ngx_str_t *sess_ctx,
}
static ngx_int_t
ngx_ssl_session_id_context(ngx_ssl_t *ssl, ngx_str_t *sess_ctx)
{
int n, i;
X509 *cert;
X509_NAME *name;
EVP_MD_CTX md;
unsigned int len;
STACK_OF(X509_NAME) *list;
u_char buf[EVP_MAX_MD_SIZE];
/*
* Session ID context is set based on the string provided,
* the server certificate, and the client CA list.
*/
EVP_MD_CTX_init(&md);
if (EVP_DigestInit_ex(&md, EVP_sha1(), NULL) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"EVP_DigestInit_ex() failed");
goto failed;
}
if (EVP_DigestUpdate(&md, sess_ctx->data, sess_ctx->len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"EVP_DigestUpdate() failed");
goto failed;
}
cert = SSL_CTX_get_ex_data(ssl->ctx, ngx_ssl_certificate_index);
if (X509_digest(cert, EVP_sha1(), buf, &len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"X509_digest() failed");
goto failed;
}
if (EVP_DigestUpdate(&md, buf, len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"EVP_DigestUpdate() failed");
goto failed;
}
list = SSL_CTX_get_client_CA_list(ssl->ctx);
if (list != NULL) {
n = sk_X509_NAME_num(list);
for (i = 0; i < n; i++) {
name = sk_X509_NAME_value(list, i);
if (X509_NAME_digest(name, EVP_sha1(), buf, &len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"X509_NAME_digest() failed");
goto failed;
}
if (EVP_DigestUpdate(&md, buf, len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"EVP_DigestUpdate() failed");
goto failed;
}
}
}
if (EVP_DigestFinal_ex(&md, buf, &len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"EVP_DigestUpdate() failed");
goto failed;
}
EVP_MD_CTX_cleanup(&md);
if (SSL_CTX_set_session_id_context(ssl->ctx, buf, len) == 0) {
ngx_ssl_error(NGX_LOG_EMERG, ssl->log, 0,
"SSL_CTX_set_session_id_context() failed");
return NGX_ERROR;
}
return NGX_OK;
failed:
EVP_MD_CTX_cleanup(&md);
return NGX_ERROR;
}
ngx_int_t
ngx_ssl_session_cache_init(ngx_shm_zone_t *shm_zone, void *data)
{