Add support for distinct certificate chains per key type and per SSL
authorDr. Stephen Henson <steve@openssl.org>
Tue, 31 Jan 2012 14:00:10 +0000 (14:00 +0000)
committerDr. Stephen Henson <steve@openssl.org>
Tue, 31 Jan 2012 14:00:10 +0000 (14:00 +0000)
structure.

Before this the only way to add a custom chain was in the parent SSL_CTX
(which is shared by all key types and SSL structures) or rely on auto
chain building (which is performed on each handshake) from the trust store.

CHANGES
ssl/s3_lib.c
ssl/ssl.h
ssl/ssl_cert.c
ssl/ssl_locl.h

diff --git a/CHANGES b/CHANGES
index 39fa10f2923041dbdd7ada204aec57920c1bd27f..86b2f92583556308e43d79a5ad39be5186e40edb 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,10 @@
 
  Changes between 1.0.1 and 1.1.0  [xx XXX xxxx]
 
+  *) Enhance SSL/TLS certificate chain handling to support different
+     chains for each certificate instead of one chain in the parent SSL_CTX.
+     [Steve Henson]
+
   *) Support for fixed DH ciphersuite client authentication: where both
      server and client use DH certificates with common parameters.
      [Steve Henson]
index b488cdbb35a1ae2857d10d03d96c4324e4696087..d96937915751c90ba8d8e5d5186646eff10eb1c7 100644 (file)
@@ -3350,6 +3350,21 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
 #endif
 
 #endif /* !OPENSSL_NO_TLSEXT */
+
+       case SSL_CTRL_CHAIN:
+               if (larg)
+                       return ssl_cert_set1_chain(s->cert,
+                                               (STACK_OF (X509) *)parg);
+               else
+                       return ssl_cert_set0_chain(s->cert,
+                                               (STACK_OF (X509) *)parg);
+
+       case SSL_CTRL_CHAIN_CERT:
+               if (larg)
+                       return ssl_cert_add1_chain_cert(s->cert, (X509 *)parg);
+               else
+                       return ssl_cert_add0_chain_cert(s->cert, (X509 *)parg);
+
        default:
                break;
                }
@@ -3642,6 +3657,20 @@ long ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
                        }
                break;
 
+       case SSL_CTRL_CHAIN:
+               if (larg)
+                       return ssl_cert_set1_chain(ctx->cert,
+                                               (STACK_OF (X509) *)parg);
+               else
+                       return ssl_cert_set0_chain(ctx->cert,
+                                               (STACK_OF (X509) *)parg);
+
+       case SSL_CTRL_CHAIN_CERT:
+               if (larg)
+                       return ssl_cert_add1_chain_cert(ctx->cert, (X509 *)parg);
+               else
+                       return ssl_cert_add0_chain_cert(ctx->cert, (X509 *)parg);
+
        default:
                return(0);
                }
index b9325feb41f402493e555bdafede45148a6e58d7..3d027af3cca3ee30929089edfb7194cad2430388 100644 (file)
--- a/ssl/ssl.h
+++ b/ssl/ssl.h
@@ -1615,6 +1615,9 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
 #define SSL_CTRL_GET_EXTRA_CHAIN_CERTS         82
 #define SSL_CTRL_CLEAR_EXTRA_CHAIN_CERTS       83
 
+#define SSL_CTRL_CHAIN                         88
+#define SSL_CTRL_CHAIN_CERT                    89
+
 #define DTLSv1_get_timeout(ssl, arg) \
        SSL_ctrl(ssl,DTLS_CTRL_GET_TIMEOUT,0, (void *)arg)
 #define DTLSv1_handle_timeout(ssl) \
@@ -1656,6 +1659,24 @@ DECLARE_PEM_rw(SSL_SESSION, SSL_SESSION)
 #define SSL_CTX_clear_extra_chain_certs(ctx) \
        SSL_CTX_ctrl(ctx,SSL_CTRL_CLEAR_EXTRA_CHAIN_CERTS,0,NULL)
 
+#define SSL_CTX_set0_chain(ctx,sk) \
+       SSL_CTX_ctrl(ctx,SSL_CTRL_CHAIN,0,(char *)sk)
+#define SSL_CTX_set1_chain(ctx,sk) \
+       SSL_CTX_ctrl(ctx,SSL_CTRL_CHAIN,1,(char *)sk)
+#define SSL_CTX_add0_chain_cert(ctx,x509) \
+       SSL_CTX_ctrl(ctx,SSL_CTRL_CHAIN_CERT,0,(char *)x509)
+#define SSL_CTX_add1_chain_cert(ctx,x509) \
+       SSL_CTX_ctrl(ctx,SSL_CTRL_CHAIN_CERT,1,(char *)x509)
+
+#define SSL_set0_chain(ctx,sk) \
+       SSL_ctrl(ctx,SSL_CTRL_CHAIN,0,(char *)sk)
+#define SSL_set1_chain(ctx,sk) \
+       SSL_ctrl(ctx,SSL_CTRL_CHAIN,1,(char *)sk)
+#define SSL_add0_chain_cert(ctx,x509) \
+       SSL_ctrl(ctx,SSL_CTRL_CHAIN_CERT,0,(char *)x509)
+#define SSL_add1_chain_cert(ctx,x509) \
+       SSL_ctrl(ctx,SSL_CTRL_CHAIN_CERT,1,(char *)x509)
+
 #ifndef OPENSSL_NO_BIO
 BIO_METHOD *BIO_f_ssl(void);
 BIO *BIO_new_ssl(SSL_CTX *ctx,int client);
index 94b6deadc16fccda7e0f8531364089aaa7075f34..2f43d2ede1437c1965cd09de8823fa826d7221a1 100644 (file)
@@ -317,11 +317,23 @@ CERT *ssl_cert_dup(CERT *cert)
                                SSLerr(SSL_F_SSL_CERT_DUP, SSL_R_LIBRARY_BUG);
                                }
                        }
+
+               if (cpk->chain)
+                       {
+                       rpk->chain = sk_X509_dup(cpk->chain);
+                       if (!rpk->chain)
+                               {
+                               SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
+                               goto err;
+                               }
+                       for (i = 0; i < sk_X509_num(rpk->chain); i++)
+                               {
+                               X509 *x = sk_X509_value(rpk->chain, i);
+                               CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);
+                               }
+                       }
                }
        
-       /* ret->extra_certs *should* exist, but currently the own certificate
-        * chain is held inside SSL_CTX */
-
        ret->references=1;
        /* Set digests to defaults. NB: we don't copy existing values as they
         * will be set during handshake.
@@ -353,6 +365,8 @@ err:
                        X509_free(rpk->x509);
                if (rpk->privatekey != NULL)
                        EVP_PKEY_free(rpk->privatekey);
+               if (rpk->chain)
+                       sk_X509_pop_free(rpk->chain, X509_free);
                }
 
 
@@ -397,6 +411,8 @@ void ssl_cert_free(CERT *c)
                        X509_free(cpk->x509);
                if (cpk->privatekey != NULL)
                        EVP_PKEY_free(cpk->privatekey);
+               if (cpk->chain)
+                       sk_X509_pop_free(cpk->chain, X509_free);
 #if 0
                if (c->pkeys[i].publickey != NULL)
                        EVP_PKEY_free(c->pkeys[i].publickey);
@@ -433,6 +449,59 @@ int ssl_cert_inst(CERT **o)
        return(1);
        }
 
+int ssl_cert_set0_chain(CERT *c, STACK_OF(X509) *chain)
+       {
+       CERT_PKEY *cpk = c->key;
+       if (!cpk)
+               return 0;
+       if (cpk->chain)
+               sk_X509_pop_free(cpk->chain, X509_free);
+       cpk->chain = chain;
+       return 1;
+       }
+
+int ssl_cert_set1_chain(CERT *c, STACK_OF(X509) *chain)
+       {
+       STACK_OF(X509) *dchain;
+       X509 *x;
+       int i;
+       if (!chain)
+               return ssl_cert_set0_chain(c, NULL);
+       dchain = sk_X509_dup(chain);
+       if (!dchain)
+               return 0;
+       for (i = 0; i < sk_X509_num(dchain); i++)
+               {
+               x = sk_X509_value(dchain, i);
+               CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);
+               }
+       if (!ssl_cert_set0_chain(c, dchain))
+               {
+               sk_X509_pop_free(dchain, X509_free);
+               return 0;
+               }
+       return 1;
+       }
+
+int ssl_cert_add0_chain_cert(CERT *c, X509 *x)
+       {
+       CERT_PKEY *cpk = c->key;
+       if (!cpk)
+               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(CERT *c, X509 *x)
+       {
+       if (!ssl_cert_add0_chain_cert(c, x))
+               return 0;
+       CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);
+       return 1;
+       }
 
 SESS_CERT *ssl_sess_cert_new(void)
        {
@@ -884,13 +953,22 @@ int ssl_add_cert_chain(SSL *s, CERT_PKEY *cpk, unsigned long *l)
        int i;
 
        X509 *x;
+       STACK_OF(X509) *extra_certs;
 
        if (cpk)
                x = cpk->x509;
        else
                x = NULL;
 
-       if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || s->ctx->extra_certs)
+       /* If we have a certificate specific chain use it, else use
+        * parent ctx.
+        */
+       if (cpk && cpk->chain)
+               extra_certs = cpk->chain;
+       else
+               extra_certs = s->ctx->extra_certs;
+
+       if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || extra_certs)
                no_chain = 1;
        else
                no_chain = 0;
@@ -933,10 +1011,9 @@ int ssl_add_cert_chain(SSL *s, CERT_PKEY *cpk, unsigned long *l)
                        X509_STORE_CTX_cleanup(&xs_ctx);
                        }
                }
-       /* Thawte special :-) */
-       for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++)
+       for (i=0; i<sk_X509_num(extra_certs); i++)
                {
-               x=sk_X509_value(s->ctx->extra_certs,i);
+               x=sk_X509_value(extra_certs,i);
                if (!ssl_add_cert_to_buf(buf, l, x))
                        return 0;
                }
index 66605586ac13aa82058ff1b0c1ef2199e5a13183..95b531e8324c717cb950ca958862e4b15587b680 100644 (file)
@@ -472,6 +472,8 @@ typedef struct cert_pkey_st
        EVP_PKEY *privatekey;
        /* Digest to use when signing */
        const EVP_MD *digest;
+       /* Chain for this certificate */
+       STACK_OF(X509) *chain;
        } CERT_PKEY;
 
 typedef struct cert_st
@@ -824,6 +826,11 @@ void ssl_update_cache(SSL *s, int mode);
 int ssl_cipher_get_evp(const SSL_SESSION *s,const EVP_CIPHER **enc,
                       const EVP_MD **md,int *mac_pkey_type,int *mac_secret_size, SSL_COMP **comp);
 int ssl_get_handshake_digest(int i,long *mask,const EVP_MD **md);                         
+int ssl_cert_set0_chain(CERT *c, STACK_OF(X509) *chain);
+int ssl_cert_set1_chain(CERT *c, STACK_OF(X509) *chain);
+int ssl_cert_add0_chain_cert(CERT *c, X509 *x);
+int ssl_cert_add1_chain_cert(CERT *c, X509 *x);
+
 int ssl_verify_cert_chain(SSL *s,STACK_OF(X509) *sk);
 int ssl_add_cert_chain(SSL *s, CERT_PKEY *cpk, unsigned long *l);
 int ssl_undefined_function(SSL *s);