openssl
/
openssl
mirror of https://github.com/openssl/openssl
1
0
Fork 0
Code Issues Releases Wiki Activity

For better forward-security support, add functions 

SSL_[CTX_]set_not_resumable_session_callback.

Submitted by: Emilia Kasper (Google)

[A part of this change affecting ssl/s3_lib.c was accidentally commited
separately, together with a compilation fix for that file;
see s3_lib.c CVS revision 1.133 (http://cvs.openssl.org/chngview?cn=19855).]
This commit is contained in:
Bodo Möller 2010-08-26 15:15:47 +00:00
parent f16176dab4
commit 7c2d4fee25
5 changed files with 80 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
CHANGES
View File

@ -4,6 +4,24 @@
Changes between 1.0.0 and 1.1.0 [xx XXX xxxx]
*) Improve forward-security support: add functions
void SSL_CTX_set_not_resumable_session_callback(SSL_CTX *ctx, int (*cb)(SSL *ssl, int is_forward_secure))
void SSL_set_not_resumable_session_callback(SSL *ssl, int (*cb)(SSL *ssl, int is_forward_secure))
for use by SSL/TLS servers; the callback function will be called whenever a
new session is created, and gets to decide whether the session may be
cached to make it resumable (return 0) or not (return 1). (As by the
SSL/TLS protocol specifications, the session_id sent by the server will be
empty to indicate that the session is not resumable; also, the server will
not generate RFC 4507 (RFC 5077) session tickets.)
A simple reasonable callback implementation is to return is_forward_secure.
This parameter will be set to 1 or 0 depending on the ciphersuite selected
by the SSL/TLS server library, indicating whether it can provide forward
security.
[Emilia Käsper <emilia.kasper@esat.kuleuven.be> (Google)]
*) Add Next Protocol Negotiation,
http://tools.ietf.org/html/draft-agl-tls-nextprotoneg-00. Can be
disabled with a no-npn flag to config or Configure. Code donated

20
apps/s_server.c
View File

@ -201,6 +201,7 @@ typedef unsigned int u_int;
#ifndef OPENSSL_NO_RSA
static RSA MS_CALLBACK *tmp_rsa_cb(SSL *s, int is_export, int keylength);
#endif
static int not_resumable_sess_cb(SSL *s, int is_forward_secure);
static int sv_body(char *hostname, int s, unsigned char *context);
static int www_body(char *hostname, int s, unsigned char *context);
static void close_accept_socket(void );
@ -289,6 +290,7 @@ static int s_tlsextdebug=0;
static int s_tlsextstatus=0;
static int cert_status_cb(SSL *s, void *arg);
#endif
static int no_resume_ephemeral = 0;
static int s_msg=0;
static int s_quiet=0;
@ -476,6 +478,7 @@ static void sv_usage(void)
#ifndef OPENSSL_NO_ECDH
BIO_printf(bio_err," -no_ecdhe - Disable ephemeral ECDH\n");
#endif
BIO_printf(bio_err, "-no_resume_ephemeral - Disable caching and tickets if ephemeral (EC)DH is used\n");
BIO_printf(bio_err," -bugs - Turn on SSL bug compatibility\n");
BIO_printf(bio_err," -www - Respond to a 'GET /' with a status page\n");
BIO_printf(bio_err," -WWW - Respond to a 'GET /<path> HTTP/1.0' with file ./<path>\n");
@ -853,6 +856,12 @@ static int next_proto_cb(SSL *s, const unsigned char **data, unsigned int *len,
# endif /* ndef OPENSSL_NO_NPN */
#endif
static int not_resumable_sess_cb(SSL *s, int is_forward_secure)
{
/* disable resumption for sessions with forward secure ciphers */
return is_forward_secure;
}
int MAIN(int, char **);
#ifndef OPENSSL_NO_JPAKE
@ -1120,6 +1129,8 @@ int MAIN(int argc, char *argv[])
{ no_dhe=1; }
else if (strcmp(*argv,"-no_ecdhe") == 0)
{ no_ecdhe=1; }
else if (strcmp(*argv,"-no_resume_ephemeral") == 0)
{ no_resume_ephemeral = 1; }
#ifndef OPENSSL_NO_PSK
else if (strcmp(*argv,"-psk_hint") == 0)
{
@ -1689,6 +1700,15 @@ bad:
#endif
#endif
if (no_resume_ephemeral)
{
SSL_CTX_set_not_resumable_session_callback(ctx, not_resumable_sess_cb);
#ifndef OPENSSL_NO_TLSEXT
if (ctx2)
SSL_CTX_set_not_resumable_session_callback(ctx2, not_resumable_sess_cb);
#endif
}
#ifndef OPENSSL_NO_PSK
#ifdef OPENSSL_NO_JPAKE
if (psk_key != NULL)

12
ssl/s3_srvr.c
View File

@ -1251,6 +1251,13 @@ int ssl3_get_client_hello(SSL *s)
goto f_err;
}
s->s3->tmp.new_cipher=c;
/* check whether we should disable session resumption */
if (s->not_resumable_session_cb != NULL)
s->session->not_resumable=s->not_resumable_session_cb(s,
((c->algorithm_mkey & (SSL_kEDH | SSL_kEECDH)) != 0));
if (s->session->not_resumable)
/* do not send a session ticket */
s->tlsext_ticket_expected = 0;
}
else
{
@ -1354,8 +1361,9 @@ int ssl3_send_server_hello(SSL *s)
* if session caching is disabled so existing functionality
* is unaffected.
*/
if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
&& !s->hit)
if (s->session->not_resumable ||
(!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)
&& !s->hit))
s->session->session_id_length=0;
sl=s->session->session_id_length;

18
ssl/ssl.h
View File

@ -468,6 +468,9 @@ typedef struct ssl_session_st
char *psk_identity_hint;
char *psk_identity;
#endif
/* Used to indicate that session resumption is not allowed.
* Applications can also set this bit for a new session via
* not_resumable_session_cb to disable session caching and tickets. */
int not_resumable;
/* The cert is the certificate used to establish this connection */
@ -811,6 +814,10 @@ struct ssl_ctx_st
X509_VERIFY_PARAM *param;
/* Callback for disabling session caching and ticket support
* on a session basis, depending on the chosen cipher. */
int (*not_resumable_session_cb)(SSL *ssl, int is_forward_secure);
#if 0
int purpose; /* Purpose setting */
int trust; /* Trust setting */
@ -1088,6 +1095,10 @@ struct ssl_st
X509_VERIFY_PARAM *param;
/* Callback for disabling session caching and ticket support
* on a session basis, depending on the chosen cipher. */
int (*not_resumable_session_cb)(SSL *ssl, int is_forward_secure);
#if 0
int purpose; /* Purpose setting */
int trust; /* Trust setting */
@ -1477,6 +1488,7 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
#define SSL_CTRL_GET_RI_SUPPORT 76
#define SSL_CTRL_CLEAR_OPTIONS 77
#define SSL_CTRL_CLEAR_MODE 78
#define SSL_CTRL_SET_NOT_RESUMABLE_SESS_CB 79
#define DTLSv1_get_timeout(ssl, arg) \
SSL_ctrl(ssl,DTLS_CTRL_GET_TIMEOUT,0, (void *)arg)
@ -1875,6 +1887,12 @@ int SSL_tls1_key_exporter(SSL *s, unsigned char *label, int label_len,
unsigned char *context, int context_len,
unsigned char *out, int olen);
void SSL_CTX_set_not_resumable_session_callback(SSL_CTX *ctx,
int (*cb)(SSL *ssl, int is_forward_secure));
void SSL_set_not_resumable_session_callback(SSL *ssl,
int (*cb)(SSL *ssl, int is_forward_secure));
/* BEGIN ERROR CODES */
/* The following lines are auto generated by the script mkerr.pl. Any changes
* made after this point may be overwritten when the script is next run.

14
ssl/ssl_lib.c
View File

@ -319,6 +319,7 @@ SSL *SSL_new(SSL_CTX *ctx)
s->msg_callback=ctx->msg_callback;
s->msg_callback_arg=ctx->msg_callback_arg;
s->verify_mode=ctx->verify_mode;
s->not_resumable_session_cb=ctx->not_resumable_session_cb;
#if 0
s->verify_depth=ctx->verify_depth;
#endif
@ -3164,6 +3165,19 @@ void SSL_set_msg_callback(SSL *ssl, void (*cb)(int write_p, int version, int con
SSL_callback_ctrl(ssl, SSL_CTRL_SET_MSG_CALLBACK, (void (*)(void))cb);
}
void SSL_CTX_set_not_resumable_session_callback(SSL_CTX *ctx,
int (*cb)(SSL *ssl, int is_forward_secure))
{
SSL_CTX_callback_ctrl(ctx, SSL_CTRL_SET_NOT_RESUMABLE_SESS_CB,
(void (*)(void))cb);
}
void SSL_set_not_resumable_session_callback(SSL *ssl,
int (*cb)(SSL *ssl, int is_forward_secure))
{
SSL_callback_ctrl(ssl, SSL_CTRL_SET_NOT_RESUMABLE_SESS_CB,
(void (*)(void))cb);
}
/* Allocates new EVP_MD_CTX and sets pointer to it into given pointer
* vairable, freeing EVP_MD_CTX previously stored in that variable, if
* any. If EVP_MD pointer is passed, initializes ctx with this md