Add provisional support for TLS-PSK methods
[freeradius.git] / src / main / tls.c
index f6429e0..f33841d 100644 (file)
@@ -60,6 +60,51 @@ static unsigned int  record_plus(record_t *buf, const void *ptr,
 static unsigned int    record_minus(record_t *buf, void *ptr,
                                     unsigned int size);
 
+#ifdef PSK_MAX_IDENTITY_LEN
+static unsigned int psk_server_callback(SSL *ssl, const char *identity,
+                                       unsigned char *psk, int max_psk_len)
+{
+       unsigned int psk_len;
+       fr_tls_server_conf_t *conf;
+
+       conf = (fr_tls_server_conf_t *)SSL_get_ex_data(ssl,
+                                                      FR_TLS_EX_INDEX_CONF);
+       if (!conf) return 0;
+
+       /*
+        *      FIXME: Look up the PSK password based on the identity!
+        */
+       if (strcmp(identity, conf->psk_identity) != 0) {
+               return 0;
+       }
+
+       psk_len = strlen(conf->psk_password);
+       if (psk_len > (2 * max_psk_len)) return 0;
+
+       return fr_hex2bin(conf->psk_password, psk, psk_len);
+}
+
+static unsigned int psk_client_callback(SSL *ssl, UNUSED const char *hint,
+                                       char *identity, unsigned int max_identity_len,
+                                       unsigned char *psk, unsigned int max_psk_len)
+{
+       unsigned int psk_len;
+       fr_tls_server_conf_t *conf;
+
+       conf = (fr_tls_server_conf_t *)SSL_get_ex_data(ssl,
+                                                      FR_TLS_EX_INDEX_CONF);
+       if (!conf) return 0;
+
+       psk_len = strlen(conf->psk_password);
+       if (psk_len > (2 * max_psk_len)) return 0;
+
+       strlcpy(identity, conf->psk_identity, max_identity_len);
+
+       return fr_hex2bin(conf->psk_password, psk, psk_len);
+}
+
+#endif
+
 tls_session_t *tls_new_client_session(fr_tls_server_conf_t *conf, int fd)
 {
        int verify_mode;
@@ -428,29 +473,12 @@ void session_init(tls_session_t *ssn)
 
 void session_close(tls_session_t *ssn)
 {      
-       if (ssn->ssl->session) {
-               VALUE_PAIR *vp;
-
-               vp = SSL_SESSION_get_ex_data(ssn->ssl->session,
-                                            FR_TLS_EX_INDEX_VPS);
-               if (vp) pairfree(&vp);
-       }
-
        SSL_set_quiet_shutdown(ssn->ssl, 1);
        SSL_shutdown(ssn->ssl);
 
        if(ssn->ssl)
                SSL_free(ssn->ssl);
-#if 0
-/*
- * WARNING: SSL_free seems to decrement the reference counts already,
- *     so doing this might crash the application.
- */
-       if(ssn->into_ssl)
-               BIO_free(ssn->into_ssl);
-       if(ssn->from_ssl)
-               BIO_free(ssn->from_ssl);
-#endif
+
        record_close(&ssn->clean_in);
        record_close(&ssn->clean_out);
        record_close(&ssn->dirty_in);
@@ -778,6 +806,12 @@ static CONF_PARSER tls_server_config[] = {
          offsetof(fr_tls_server_conf_t, ca_file), NULL, NULL },
        { "private_key_password", PW_TYPE_STRING_PTR,
          offsetof(fr_tls_server_conf_t, private_key_password), NULL, NULL },
+#ifdef PSK_MAX_IDENTITY_LEN
+       { "psk_identity", PW_TYPE_STRING_PTR,
+         offsetof(fr_tls_server_conf_t, psk_identity), NULL, NULL },
+       { "psk_hexphrase", PW_TYPE_STRING_PTR,
+         offsetof(fr_tls_server_conf_t, psk_password), NULL, NULL },
+#endif
        { "dh_file", PW_TYPE_STRING_PTR,
          offsetof(fr_tls_server_conf_t, dh_file), NULL, NULL },
        { "random_file", PW_TYPE_STRING_PTR,
@@ -923,8 +957,7 @@ static int generate_eph_rsa_key(SSL_CTX *ctx)
 
 
 /*
- *     These functions don't do anything other than print debugging
- *     messages.
+ *     Print debugging messages, and free data.
  *
  *     FIXME: Write sessions to some long-term storage, so that
  *            session resumption can still occur after the server
@@ -943,7 +976,6 @@ static void cbtls_remove_session(UNUSED SSL_CTX *ctx, SSL_SESSION *sess)
        fr_bin2hex(sess->session_id, buffer, size);
 
         DEBUG2("  SSL: Removing session %s from the cache", buffer);
-        SSL_SESSION_free(sess);
 
         return;
 }
@@ -960,12 +992,12 @@ static int cbtls_new_session(UNUSED SSL *s, SSL_SESSION *sess)
 
        DEBUG2("  SSL: adding session %s to cache", buffer);
 
-       return 1;
+       return 0;
 }
 
 static SSL_SESSION *cbtls_get_session(UNUSED SSL *s,
                                      unsigned char *data, int len,
-                                     UNUSED int *copy)
+                                     int *copy)
 {
        size_t size;
        char buffer[2 * MAX_SESSION_SIZE + 1];
@@ -978,6 +1010,7 @@ static SSL_SESSION *cbtls_get_session(UNUSED SSL *s,
         DEBUG2("  SSL: Client requested nonexistent cached session %s",
               buffer);
 
+       *copy = 0;
        return NULL;
 }
 
@@ -1148,12 +1181,13 @@ ocsp_end:
 /*
  *     For creating certificate attributes.
  */
-static const char *cert_attr_names[5][2] = {
+static const char *cert_attr_names[6][2] = {
   { "TLS-Client-Cert-Serial",          "TLS-Cert-Serial" },
   { "TLS-Client-Cert-Expiration",      "TLS-Cert-Expiration" },
   { "TLS-Client-Cert-Subject",         "TLS-Cert-Subject" },
   { "TLS-Client-Cert-Issuer",          "TLS-Cert-Issuer" },
-  { "TLS-Client-Cert-Common-Name",     "TLS-Cert-Common-Name" }
+  { "TLS-Client-Cert-Common-Name",     "TLS-Cert-Common-Name" },
+  { "TLS-Client-Cert-Subject-Alt-Name-Email",  "TLS-Cert-Subject-Alt-Name-Email" }
 };
 
 #define FR_TLS_SERIAL          (0)
@@ -1161,6 +1195,7 @@ static const char *cert_attr_names[5][2] = {
 #define FR_TLS_SUBJECT         (2)
 #define FR_TLS_ISSUER          (3)
 #define FR_TLS_CN              (4)
+#define FR_TLS_SAN_EMAIL               (5)
 
 /*
  *     Before trusting a certificate, you must make sure that the
@@ -1196,7 +1231,7 @@ int cbtls_verify(int ok, X509_STORE_CTX *ctx)
        char buf[64];
        X509 *client_cert;
        SSL *ssl;
-       int err, depth, lookup;
+       int err, depth, lookup, loc;
        fr_tls_server_conf_t *conf;
        int my_ok = ok;
        REQUEST *request;
@@ -1315,6 +1350,41 @@ int cbtls_verify(int ok, X509_STORE_CTX *ctx)
                        pairmake(cert_attr_names[FR_TLS_CN][lookup], common_name, T_OP_SET));
        }
 
+#ifdef GEN_EMAIL
+       /*
+        *      Get the RFC822 Subject Alternative Name
+        */
+       loc = X509_get_ext_by_NID(client_cert, NID_subject_alt_name, 0);
+       if (lookup <= 1 && loc >= 0) {
+               X509_EXTENSION *ext = NULL;
+               GENERAL_NAMES *names = NULL;
+               int i;
+
+               if ((ext = X509_get_ext(client_cert, loc)) &&
+                   (names = X509V3_EXT_d2i(ext))) {
+                       for (i = 0; i < sk_GENERAL_NAME_num(names); i++) {
+                               GENERAL_NAME *name = sk_GENERAL_NAME_value(names, i);
+
+                               switch (name->type) {
+                               case GEN_EMAIL:
+                                       if (ASN1_STRING_length(name->d.rfc822Name) >= MAX_STRING_LEN)
+                                               break;
+
+                                       pairadd(certs,
+                                               pairmake(cert_attr_names[FR_TLS_SAN_EMAIL][lookup],
+                                                        ASN1_STRING_data(name->d.rfc822Name), T_OP_SET));
+                                       break;
+                               default:
+                                       /* XXX TODO handle other SAN types */
+                                       break;
+                               }
+                       }
+               }
+               if (names != NULL)
+                       sk_GENERAL_NAME_free(names);
+       }
+#endif /* GEN_EMAIL */
+
        /*
         *      If the CRL has expired, that might still be OK.
         */
@@ -1532,6 +1602,32 @@ static int set_ecdh_curve(SSL_CTX *ctx, const char *ecdh_curve)
 #endif
 #endif
 
+/* index we use to store cached session VPs
+ * needs to be dynamic so we can supply a "free" function
+ */
+static int FR_TLS_EX_INDEX_VPS = -1;
+
+/*
+ * DIE OPENSSL DIE DIE DIE
+ *
+ * What a palaver, just to free some data attached the
+ * session. We need to do this because the "remove" callback
+ * is called when refcount > 0 sometimes, if another thread
+ * is using the session
+ */
+static void sess_free_vps(UNUSED void *parent, void *data_ptr,
+                                UNUSED CRYPTO_EX_DATA *ad, UNUSED int idx,
+                                UNUSED long argl, UNUSED void *argp)
+{
+       VALUE_PAIR *vp = data_ptr;
+       if (!vp) return;
+
+       DEBUG2("  Freeing cached session VPs %p", vp);
+
+       pairfree(&vp);
+}
+
+
 /*
  *     Create Global context SSL and use it in every new session
  *
@@ -1539,7 +1635,7 @@ static int set_ecdh_curve(SSL_CTX *ctx, const char *ecdh_curve)
  *     - Load the Private key & the certificate
  *     - Set the Context options & Verify options
  */
-static SSL_CTX *init_tls_ctx(fr_tls_server_conf_t *conf)
+static SSL_CTX *init_tls_ctx(fr_tls_server_conf_t *conf, int client)
 {
        const SSL_METHOD *meth;
        SSL_CTX *ctx;
@@ -1627,6 +1723,51 @@ static SSL_CTX *init_tls_ctx(fr_tls_server_conf_t *conf)
                SSL_CTX_set_default_passwd_cb(ctx, cbtls_password);
        }
 
+#ifdef PSK_MAX_IDENTITY_LEN
+       if ((conf->psk_identity && !conf->psk_password) ||
+           (!conf->psk_identity && conf->psk_password) ||
+           (conf->psk_identity && !*conf->psk_identity) ||
+           (conf->psk_password && !*conf->psk_password)) {
+               radlog(L_ERR, "Invalid PSK Configuration: psk_identity or psk_password are empty");
+               return NULL;
+       }
+
+       if (conf->psk_identity) {
+               size_t psk_len, hex_len;
+               char buffer[PSK_MAX_PSK_LEN];
+
+               if (conf->certificate_file ||
+                   conf->private_key_password || conf->private_key_file ||
+                   conf->ca_file || conf->ca_path) {
+                       radlog(L_ERR, "When PSKs are used, No certificate configuration is permitted");
+                       return NULL;
+               }
+
+               if (client) {
+                       SSL_CTX_set_psk_client_callback(ctx,
+                                                       psk_client_callback);
+               } else {
+                       SSL_CTX_set_psk_server_callback(ctx,
+                                                       psk_server_callback);
+               }
+
+               psk_len = strlen(conf->psk_password);
+               if (strlen(conf->psk_password) > (2 * PSK_MAX_PSK_LEN)) {
+                       radlog(L_ERR, "psk_hexphrase is too long (max %d)",
+                              PSK_MAX_PSK_LEN);
+                       return NULL;                        
+               }
+
+               hex_len = fr_hex2bin(conf->psk_password, buffer, psk_len);
+               if (psk_len != (2 * hex_len)) {
+                       radlog(L_ERR, "psk_hexphrase is not all hex");
+                       return NULL;                        
+               }
+
+               goto post_ca;
+       }
+#endif
+
        /*
         *      Load our keys and certificates
         *
@@ -1681,6 +1822,10 @@ load_ca:
                }
        }
 
+#ifdef PSK_MAX_IDENTITY_LEN
+post_ca:
+#endif
+
        /*
         *      Set ctx_options
         */
@@ -1748,6 +1893,8 @@ load_ca:
                SSL_CTX_sess_set_remove_cb(ctx, cbtls_remove_session);
 
                SSL_CTX_set_quiet_shutdown(ctx, 1);
+               if (FR_TLS_EX_INDEX_VPS < 0)
+                       FR_TLS_EX_INDEX_VPS = SSL_SESSION_get_ex_new_index(0, NULL, NULL, NULL, sess_free_vps);
        }
 
        /*
@@ -1805,12 +1952,12 @@ load_ca:
                if (conf->session_id_name) {
                        snprintf(conf->session_context_id,
                                 sizeof(conf->session_context_id),
-                                "FreeRADIUS EAP-TLS %s",
+                                "FR eap %s",
                                 conf->session_id_name);
                } else {
                        snprintf(conf->session_context_id,
                                 sizeof(conf->session_context_id),
-                                "FreeRADIUS EAP-TLS %p", conf);
+                                "FR eap %p", conf);
                }
 
                /*
@@ -1914,7 +2061,7 @@ fr_tls_server_conf_t *tls_server_conf_parse(CONF_SECTION *cs)
        /*
         *      Initialize TLS
         */
-       conf->ctx = init_tls_ctx(conf);
+       conf->ctx = init_tls_ctx(conf, 0);
        if (conf->ctx == NULL) {
                goto error;
        }
@@ -1977,7 +2124,7 @@ fr_tls_server_conf_t *tls_client_conf_parse(CONF_SECTION *cs)
        /*
         *      Initialize TLS
         */
-       conf->ctx = init_tls_ctx(conf);
+       conf->ctx = init_tls_ctx(conf, 1);
        if (conf->ctx == NULL) {
                goto error;
        }
@@ -2031,7 +2178,14 @@ int tls_success(tls_session_t *ssn, REQUEST *request)
                 *      user data in the cache.
                 */
        } else if (!SSL_session_reused(ssn->ssl)) {
-               RDEBUG2("Saving response in the cache");
+               size_t size;
+               char buffer[2 * MAX_SESSION_SIZE + 1];
+
+               size = ssn->ssl->session->session_id_length;
+               if (size > MAX_SESSION_SIZE) size = MAX_SESSION_SIZE;
+
+               fr_bin2hex(ssn->ssl->session->session_id, buffer, size);
+
                
                vp = paircopy2(request->reply->vps, PW_USER_NAME, 0);
                if (vp) pairadd(&vps, vp);
@@ -2043,10 +2197,11 @@ int tls_success(tls_session_t *ssn, REQUEST *request)
                if (vp) pairadd(&vps, vp);
                
                if (vps) {
+                       RDEBUG2("Saving session %s vps %p in the cache", buffer, vps);
                        SSL_SESSION_set_ex_data(ssn->ssl->session,
                                                FR_TLS_EX_INDEX_VPS, vps);
                } else {
-                       RDEBUG2("WARNING: No information to cache: session caching will be disabled for this session.");
+                       RDEBUG2("WARNING: No information to cache: session caching will be disabled for session %s", buffer);
                        SSL_CTX_remove_session(ssn->ctx,
                                               ssn->ssl->session);
                }
@@ -2056,15 +2211,23 @@ int tls_success(tls_session_t *ssn, REQUEST *request)
                 *      reply.
                 */
        } else {
+               size_t size;
+               char buffer[2 * MAX_SESSION_SIZE + 1];
+
+               size = ssn->ssl->session->session_id_length;
+               if (size > MAX_SESSION_SIZE) size = MAX_SESSION_SIZE;
+
+               fr_bin2hex(ssn->ssl->session->session_id, buffer, size);
+
               
                vp = SSL_SESSION_get_ex_data(ssn->ssl->session,
                                             FR_TLS_EX_INDEX_VPS);
                if (!vp) {
-                       RDEBUG("WARNING: No information in cached session!");
+                       RDEBUG("WARNING: No information in cached session %s", buffer);
                        return -1;
 
                } else {
-                       RDEBUG("Adding cached attributes to the reply:");
+                       RDEBUG("Adding cached attributes for session %s vps %p to the reply:", buffer, vp);
                        debug_pair_list(vp);
                        pairadd(&request->reply->vps, paircopy(vp));