Export variable with session expiration time
[mod_auth_gssapi.git] / src / mod_auth_gssapi.c
index 52f2531..48300e9 100644 (file)
@@ -119,6 +119,48 @@ static bool mag_conn_is_https(conn_rec *c)
     return false;
 }
 
+static char *escape(apr_pool_t *pool, const char *name,
+                    char find, const char *replace)
+{
+    char *escaped = NULL;
+    char *namecopy;
+    char *n;
+    char *p;
+
+    namecopy = apr_pstrdup(pool, name);
+    if (!namecopy) goto done;
+
+    p = strchr(namecopy, find);
+    if (!p) return namecopy;
+
+    /* first segment */
+    n = namecopy;
+    while (p) {
+        /* terminate previous segment */
+        *p = '\0';
+        if (escaped) {
+            escaped = apr_pstrcat(pool, escaped, n, replace, NULL);
+        } else {
+            escaped = apr_pstrcat(pool, n, replace, NULL);
+        }
+        if (!escaped) goto done;
+        /* move to next segment */
+        n = p + 1;
+        p = strchr(n, find);
+    }
+    /* append last segment if any */
+    if (*n) {
+        escaped = apr_pstrcat(pool, escaped, n, NULL);
+    }
+
+done:
+    if (!escaped) {
+        ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, NULL,
+                     "OOM escaping name");
+    }
+    return escaped;
+}
+
 static void mag_store_deleg_creds(request_rec *req,
                                   char *dir, char *clientname,
                                   gss_cred_id_t delegated_cred,
@@ -128,8 +170,18 @@ static void mag_store_deleg_creds(request_rec *req,
     gss_key_value_set_desc store;
     char *value;
     uint32_t maj, min;
-
-    value = apr_psprintf(req->pool, "FILE:%s/%s", dir, clientname);
+    char *escaped;
+
+    /* We need to escape away '/', we can't have path separators in
+     * a ccache file name */
+    /* first double escape the esacping char (~) if any */
+    escaped = escape(req->pool, clientname, '~', "~~");
+    if (!escaped) return;
+    /* then escape away the separator (/) if any */
+    escaped = escape(req->pool, escaped, '/', "~");
+    if (!escaped) return;
+
+    value = apr_psprintf(req->pool, "FILE:%s/%s", dir, escaped);
     if (!value) {
         ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, NULL,
                      "OOM storing delegated credentials");
@@ -155,6 +207,7 @@ static void mag_store_deleg_creds(request_rec *req,
 static int mag_auth(request_rec *req)
 {
     const char *type;
+    const char *auth_type;
     struct mag_config *cfg;
     const char *auth_header;
     char *auth_header_type;
@@ -166,6 +219,7 @@ static int mag_auth(request_rec *req)
     gss_buffer_desc output = GSS_C_EMPTY_BUFFER;
     gss_buffer_desc name = GSS_C_EMPTY_BUFFER;
     gss_name_t client = GSS_C_NO_NAME;
+    gss_cred_id_t user_cred = GSS_C_NO_CREDENTIAL;
     gss_cred_id_t acquired_cred = GSS_C_NO_CREDENTIAL;
     gss_cred_id_t delegated_cred = GSS_C_NO_CREDENTIAL;
     gss_cred_usage_t cred_usage = GSS_C_ACCEPT;
@@ -178,19 +232,53 @@ static int mag_auth(request_rec *req)
     gss_OID mech_type = GSS_C_NO_OID;
     gss_buffer_desc lname = GSS_C_EMPTY_BUFFER;
     struct mag_conn *mc = NULL;
+    bool is_basic = false;
+    gss_ctx_id_t user_ctx = GSS_C_NO_CONTEXT;
+    gss_name_t server = GSS_C_NO_NAME;
+#ifdef HAVE_GSS_KRB5_CCACHE_NAME
+    const char *user_ccache = NULL;
+    const char *orig_ccache = NULL;
+#endif
+    uint32_t init_flags = 0;
+    time_t expiration;
 
     type = ap_auth_type(req);
     if ((type == NULL) || (strcasecmp(type, "GSSAPI") != 0)) {
         return DECLINED;
     }
 
-    /* ignore auth for subrequests */
+    cfg = ap_get_module_config(req->per_dir_config, &auth_gssapi_module);
+
+    /* implicit auth for subrequests if main auth already happened */
     if (!ap_is_initial_req(req)) {
-        return OK;
+        type = ap_auth_type(req->main);
+        if ((type != NULL) && (strcasecmp(type, "GSSAPI") == 0)) {
+            /* warn if the subrequest location and the main request
+             * location have different configs */
+            if (cfg != ap_get_module_config(req->main->per_dir_config,
+                                            &auth_gssapi_module)) {
+                ap_log_rerror(APLOG_MARK, APLOG_WARNING||APLOG_NOERRNO, 0,
+                              req, "Subrequest authentication bypass on "
+                                   "location with different configuration!");
+            }
+            if (req->main->user) {
+                req->user = apr_pstrdup(req->pool, req->main->user);
+                return OK;
+            } else {
+                ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                              "The main request is tasked to establish the "
+                              "security context, can't proceed!");
+                return HTTP_UNAUTHORIZED;
+            }
+        } else {
+            ap_log_rerror(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, req,
+                          "Subrequest GSSAPI auth with no auth on the main "
+                          "request. This operation may fail if other "
+                          "subrequests already established a context or the "
+                          "mechanism requires multiple roundtrips.");
+        }
     }
 
-    cfg = ap_get_module_config(req->per_dir_config, &auth_gssapi_module);
-
     if (cfg->ssl_only) {
         if (!mag_conn_is_https(req->connection)) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
@@ -225,7 +313,10 @@ static int mag_auth(request_rec *req)
             ap_log_rerror(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, req,
                           "Already established context found!");
             apr_table_set(req->subprocess_env, "GSS_NAME", mc->gss_name);
-            req->ap_auth_type = apr_pstrdup(req->pool, "Negotiate");
+            apr_table_set(req->subprocess_env, "GSS_SESSION_EXPIRATION",
+                          apr_psprintf(req->pool,
+                                       "%ld", (long)mc->expiration));
+            req->ap_auth_type = apr_pstrdup(req->pool, mc->auth_type);
             req->user = apr_pstrdup(req->pool, mc->user_name);
             ret = OK;
             goto done;
@@ -241,21 +332,91 @@ static int mag_auth(request_rec *req)
     auth_header_type = ap_getword_white(req->pool, &auth_header);
     if (!auth_header_type) goto done;
 
-    if (strcasecmp(auth_header_type, "Negotiate") != 0) goto done;
+    if (strcasecmp(auth_header_type, "Negotiate") == 0) {
+        auth_type = "Negotiate";
+
+        auth_header_value = ap_getword_white(req->pool, &auth_header);
+        if (!auth_header_value) goto done;
+        input.length = apr_base64_decode_len(auth_header_value) + 1;
+        input.value = apr_pcalloc(req->pool, input.length);
+        if (!input.value) goto done;
+        input.length = apr_base64_decode(input.value, auth_header_value);
+    } else if ((strcasecmp(auth_header_type, "Basic") == 0) &&
+               (cfg->use_basic_auth == true)) {
+        auth_type = "Basic";
+        is_basic = true;
+
+        gss_buffer_desc ba_user;
+        gss_buffer_desc ba_pwd;
+
+        ba_pwd.value = ap_pbase64decode(req->pool, auth_header);
+        if (!ba_pwd.value) goto done;
+        ba_user.value = ap_getword_nulls_nc(req->pool,
+                                            (char **)&ba_pwd.value, ':');
+        if (!ba_user.value) goto done;
+        if (((char *)ba_user.value)[0] == '\0' ||
+            ((char *)ba_pwd.value)[0] == '\0') {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "Invalid empty user or password for Basic Auth");
+            goto done;
+        }
+        ba_user.length = strlen(ba_user.value);
+        ba_pwd.length = strlen(ba_pwd.value);
+        maj = gss_import_name(&min, &ba_user, GSS_C_NT_USER_NAME, &client);
+        if (GSS_ERROR(maj)) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "In Basic Auth, %s",
+                          mag_error(req, "gss_import_name() failed",
+                                    maj, min));
+            goto done;
+        }
+#ifdef HAVE_GSS_KRB5_CCACHE_NAME
+        /* Set a per-thread ccache in case we are using kerberos,
+         * it is not elegant but avoids interference between threads */
+        long long unsigned int rndname;
+        apr_status_t rs;
+        rs = apr_generate_random_bytes((unsigned char *)(&rndname),
+                                       sizeof(long long unsigned int));
+        if (rs != APR_SUCCESS) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "Failed to generate random ccache name");
+            goto done;
+        }
+        user_ccache = apr_psprintf(req->pool, "MEMORY:user_%qu", rndname);
+        maj = gss_krb5_ccache_name(&min, user_ccache, &orig_ccache);
+        if (GSS_ERROR(maj)) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "In Basic Auth, %s",
+                          mag_error(req, "gss_krb5_ccache_name() "
+                                    "failed", maj, min));
+            goto done;
+        }
+#endif
+        maj = gss_acquire_cred_with_password(&min, client, &ba_pwd,
+                                             GSS_C_INDEFINITE,
+                                             GSS_C_NO_OID_SET,
+                                             GSS_C_INITIATE,
+                                             &user_cred, NULL, NULL);
+        if (GSS_ERROR(maj)) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "In Basic Auth, %s",
+                          mag_error(req, "gss_acquire_cred_with_password() "
+                                    "failed", maj, min));
+            goto done;
+        }
+        gss_release_name(&min, &client);
+    } else {
+        goto done;
+    }
 
-    auth_header_value = ap_getword_white(req->pool, &auth_header);
-    if (!auth_header_value) goto done;
-    input.length = apr_base64_decode_len(auth_header_value) + 1;
-    input.value = apr_pcalloc(req->pool, input.length);
-    if (!input.value) goto done;
-    input.length = apr_base64_decode(input.value, auth_header_value);
+    req->ap_auth_type = apr_pstrdup(req->pool, auth_type);
 
 #ifdef HAVE_GSS_ACQUIRE_CRED_FROM
     if (cfg->use_s4u2proxy) {
         cred_usage = GSS_C_BOTH;
     }
     if (cfg->cred_store) {
-        maj = gss_acquire_cred_from(&min, GSS_C_NO_NAME, 0,
+        maj = gss_acquire_cred_from(&min, GSS_C_NO_NAME, GSS_C_INDEFINITE,
                                     GSS_C_NO_OID_SET, cred_usage,
                                     cfg->cred_store, &acquired_cred,
                                     NULL, NULL);
@@ -268,6 +429,46 @@ static int mag_auth(request_rec *req)
     }
 #endif
 
+    if (is_basic) {
+        if (!acquired_cred) {
+            /* Try to acquire default creds */
+            maj = gss_acquire_cred(&min, GSS_C_NO_NAME, GSS_C_INDEFINITE,
+                                   GSS_C_NO_OID_SET, cred_usage,
+                                   &acquired_cred, NULL, NULL);
+            if (GSS_ERROR(maj)) {
+                ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                              "%s", mag_error(req, "gss_acquire_cred_from()"
+                                              " failed", maj, min));
+                goto done;
+            }
+        }
+        maj = gss_inquire_cred(&min, acquired_cred, &server,
+                               NULL, NULL, NULL);
+        if (GSS_ERROR(maj)) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "%s", mag_error(req, "gss_inquired_cred_() "
+                                          "failed", maj, min));
+            goto done;
+        }
+
+        if (cfg->deleg_ccache_dir) {
+            /* delegate ourselves credentials so we store them as requested */
+            init_flags |= GSS_C_DELEG_FLAG;
+        }
+
+        /* output and input are inverted here, this is intentional */
+        maj = gss_init_sec_context(&min, user_cred, &user_ctx, server,
+                                   GSS_C_NO_OID, init_flags, 300,
+                                   GSS_C_NO_CHANNEL_BINDINGS, &output,
+                                   NULL, &input, NULL, NULL);
+        if (GSS_ERROR(maj)) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "%s", mag_error(req, "gss_init_sec_context() "
+                                          "failed", maj, min));
+            goto done;
+        }
+    }
+
     maj = gss_accept_sec_context(&min, pctx, acquired_cred,
                                  &input, GSS_C_NO_CHANNEL_BINDINGS,
                                  &client, &mech_type, &output, &flags, &vtime,
@@ -278,8 +479,33 @@ static int mag_auth(request_rec *req)
                                 maj, min));
         goto done;
     }
-
-    if (maj == GSS_S_CONTINUE_NEEDED) {
+    if (is_basic) {
+        while (maj == GSS_S_CONTINUE_NEEDED) {
+            gss_release_buffer(&min, &input);
+            /* output and input are inverted here, this is intentional */
+            maj = gss_init_sec_context(&min, user_cred, &user_ctx, server,
+                                       GSS_C_NO_OID, init_flags, 300,
+                                       GSS_C_NO_CHANNEL_BINDINGS, &output,
+                                       NULL, &input, NULL, NULL);
+            if (GSS_ERROR(maj)) {
+                ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                              "%s", mag_error(req, "gss_init_sec_context() "
+                                              "failed", maj, min));
+                goto done;
+            }
+            gss_release_buffer(&min, &output);
+            maj = gss_accept_sec_context(&min, pctx, acquired_cred,
+                                         &input, GSS_C_NO_CHANNEL_BINDINGS,
+                                         &client, &mech_type, &output, &flags,
+                                         &vtime, &delegated_cred);
+            if (GSS_ERROR(maj)) {
+                ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                              "%s", mag_error(req, "gss_accept_sec_context()"
+                                              " failed", maj, min));
+                goto done;
+            }
+        }
+    } else if (maj == GSS_S_CONTINUE_NEEDED) {
         if (!mc) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
                           "Mechanism needs continuation but neither "
@@ -293,8 +519,6 @@ static int mag_auth(request_rec *req)
         goto done;
     }
 
-    req->ap_auth_type = apr_pstrdup(req->pool, "Negotiate");
-
     /* Always set the GSS name in an env var */
     maj = gss_display_name(&min, client, &name, NULL);
     if (GSS_ERROR(maj)) {
@@ -305,6 +529,9 @@ static int mag_auth(request_rec *req)
     }
     clientname = apr_pstrndup(req->pool, name.value, name.length);
     apr_table_set(req->subprocess_env, "GSS_NAME", clientname);
+    expiration = time(NULL) + vtime;
+    apr_table_set(req->subprocess_env, "GSS_SESSION_EXPIRATION",
+                  apr_psprintf(req->pool, "%ld", (long)expiration));
 
 #ifdef HAVE_GSS_STORE_CRED_INTO
     if (cfg->deleg_ccache_dir && delegated_cred != GSS_C_NO_CREDENTIAL) {
@@ -338,33 +565,53 @@ static int mag_auth(request_rec *req)
         if (vtime == GSS_C_INDEFINITE || vtime < MIN_SESS_EXP_TIME) {
             vtime = MIN_SESS_EXP_TIME;
         }
-        mc->expiration = time(NULL) + vtime;
+        mc->expiration = expiration;
         if (cfg->use_sessions) {
             mag_attempt_session(req, cfg, mc);
         }
+        mc->auth_type = auth_type;
     }
 
     ret = OK;
 
 done:
-    if (ret == HTTP_UNAUTHORIZED) {
-        if (output.length != 0) {
-            replen = apr_base64_encode_len(output.length) + 1;
-            reply = apr_pcalloc(req->pool, 10 + replen);
-            if (reply) {
-                memcpy(reply, "Negotiate ", 10);
-                apr_base64_encode(&reply[10], output.value, output.length);
-                apr_table_add(req->err_headers_out,
-                              "WWW-Authenticate", reply);
-            }
-        } else {
+    if ((!is_basic) && (output.length != 0)) {
+        replen = apr_base64_encode_len(output.length) + 1;
+        reply = apr_pcalloc(req->pool, 10 + replen);
+        if (reply) {
+            memcpy(reply, "Negotiate ", 10);
+            apr_base64_encode(&reply[10], output.value, output.length);
+            apr_table_add(req->err_headers_out,
+                          "WWW-Authenticate", reply);
+        }
+    } else if (ret == HTTP_UNAUTHORIZED) {
+        apr_table_add(req->err_headers_out,
+                      "WWW-Authenticate", "Negotiate");
+        if (cfg->use_basic_auth) {
             apr_table_add(req->err_headers_out,
-                          "WWW-Authenticate", "Negotiate");
+                          "WWW-Authenticate",
+                          apr_psprintf(req->pool, "Basic realm=\"%s\"",
+                                       ap_auth_name(req)));
+        }
+    }
+#ifdef HAVE_GSS_KRB5_CCACHE_NAME
+    if (user_ccache != NULL) {
+        maj = gss_krb5_ccache_name(&min, orig_ccache, NULL);
+        if (maj != GSS_S_COMPLETE) {
+            ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
+                          "Failed to restore per-thread ccache, %s",
+                          mag_error(req, "gss_krb5_ccache_name() "
+                                    "failed", maj, min));
         }
     }
+#endif
+    gss_delete_sec_context(&min, &user_ctx, &output);
+    gss_release_cred(&min, &user_cred);
+    gss_release_cred(&min, &acquired_cred);
     gss_release_cred(&min, &delegated_cred);
     gss_release_buffer(&min, &output);
     gss_release_name(&min, &client);
+    gss_release_name(&min, &server);
     gss_release_buffer(&min, &name);
     gss_release_buffer(&min, &lname);
     return ret;
@@ -541,6 +788,14 @@ static const char *mag_deleg_ccache_dir(cmd_parms *parms, void *mconfig,
     return NULL;
 }
 
+static const char *mag_use_basic_auth(cmd_parms *parms, void *mconfig, int on)
+{
+    struct mag_config *cfg = (struct mag_config *)mconfig;
+
+    cfg->use_basic_auth = on ? true : false;
+    return NULL;
+}
+
 static const command_rec mag_commands[] = {
     AP_INIT_FLAG("GssapiSSLonly", mag_ssl_only, NULL, OR_AUTHCFG,
                   "Work only if connection is SSL Secured"),
@@ -562,6 +817,10 @@ static const command_rec mag_commands[] = {
     AP_INIT_RAW_ARGS("GssapiDelegCcacheDir", mag_deleg_ccache_dir, NULL,
                      OR_AUTHCFG, "Directory to store delegated credentials"),
 #endif
+#ifdef HAVE_GSS_ACQUIRE_CRED_WITH_PASSWORD
+    AP_INIT_FLAG("GssapiBasicAuth", mag_use_basic_auth, NULL, OR_AUTHCFG,
+                     "Allows use of Basic Auth for authentication"),
+#endif
     { NULL }
 };