- dtucker@cvs.openbsd.org 2013/05/16 04:09:14

     [sshd_config.5 servconf.c servconf.h packet.c serverloop.c monitor.c sshd_config
     sshd.c] Add RekeyLimit to sshd with the same syntax as the client allowing
     rekeying based on traffic volume or time.  ok djm@, help & ok jmc@ for the man
     page.

1 files changed, 70 insertions, 5 deletions

diff --git a/servconf.c b/servconf.c
index b2a60fd6c..4e3026b83 100644
--- a/servconf.c
+++ b/servconf.c
@@ -1,5 +1,5 @@
 
-/* $OpenBSD: servconf.c,v 1.234 2013/02/06 00:20:42 dtucker Exp $ */
+/* $OpenBSD: servconf.c,v 1.235 2013/05/16 04:09:14 dtucker Exp $ */
 /*
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
  *                    All rights reserved
@@ -20,6 +20,7 @@
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
 
+#include <ctype.h>
 #include <netdb.h>
 #include <pwd.h>
 #include <stdio.h>
@@ -110,6 +111,8 @@ initialize_server_options(ServerOptions *options)
         options->permit_user_env = -1;
         options->use_login = -1;
         options->compression = -1;
+        options->rekey_limit = -1;
+        options->rekey_interval = -1;
         options->allow_tcp_forwarding = -1;
         options->allow_agent_forwarding = -1;
         options->num_allow_users = 0;
@@ -249,6 +252,10 @@ fill_default_server_options(ServerOptions *options)
                 options->use_login = 0;
         if (options->compression == -1)
                 options->compression = COMP_DELAYED;
+        if (options->rekey_limit == -1)
+                options->rekey_limit = 0;
+        if (options->rekey_interval == -1)
+                options->rekey_interval = 0;
         if (options->allow_tcp_forwarding == -1)
                 options->allow_tcp_forwarding = FORWARD_ALLOW;
         if (options->allow_agent_forwarding == -1)
@@ -320,7 +327,7 @@ typedef enum {
         sX11Forwarding, sX11DisplayOffset, sX11UseLocalhost,
         sStrictModes, sEmptyPasswd, sTCPKeepAlive,
         sPermitUserEnvironment, sUseLogin, sAllowTcpForwarding, sCompression,
-        sAllowUsers, sDenyUsers, sAllowGroups, sDenyGroups,
+        sRekeyLimit, sAllowUsers, sDenyUsers, sAllowGroups, sDenyGroups,
         sIgnoreUserKnownHosts, sCiphers, sMacs, sProtocol, sPidFile,
         sGatewayPorts, sPubkeyAuthentication, sXAuthLocation, sSubsystem,
         sMaxStartups, sMaxAuthTries, sMaxSessions,
@@ -422,6 +429,7 @@ static struct {
         { "permituserenvironment", sPermitUserEnvironment, SSHCFG_GLOBAL },
         { "uselogin", sUseLogin, SSHCFG_GLOBAL },
         { "compression", sCompression, SSHCFG_GLOBAL },
+        { "rekeylimit", sRekeyLimit, SSHCFG_ALL },
         { "tcpkeepalive", sTCPKeepAlive, SSHCFG_GLOBAL },
         { "keepalive", sTCPKeepAlive, SSHCFG_GLOBAL },  /* obsolete alias */
         { "allowtcpforwarding", sAllowTcpForwarding, SSHCFG_ALL },
@@ -800,14 +808,14 @@ process_server_config_line(ServerOptions *options, char *line,
     const char *filename, int linenum, int *activep,
     struct connection_info *connectinfo)
 {
-        char *cp, **charptr, *arg, *p;
-        int cmdline = 0, *intptr, value, value2, n;
+        char *cp, **charptr, *arg, *p, *endofnumber;
+        int cmdline = 0, *intptr, value, value2, n, port, scale;
         SyslogFacility *log_facility_ptr;
         LogLevel *log_level_ptr;
         ServerOpCodes opcode;
-        int port;
         u_int i, flags = 0;
         size_t len;
+        long long orig, val64;
         const struct multistate *multistate_ptr;
 
         cp = line;
@@ -1118,6 +1126,59 @@ process_server_config_line(ServerOptions *options, char *line,
                 multistate_ptr = multistate_compression;
                 goto parse_multistate;
 
+        case sRekeyLimit:
+                arg = strdelim(&cp);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename,
+                            linenum);
+                if (strcmp(arg, "default") == 0) {
+                        val64 = 0;
+                } else {
+                        if (arg[0] < '0' || arg[0] > '9')
+                                fatal("%.200s line %d: Bad number.", filename,
+                                    linenum);
+                        orig = val64 = strtoll(arg, &endofnumber, 10);
+                        if (arg == endofnumber)
+                                fatal("%.200s line %d: Bad number.", filename,
+                         linenum);
+                        switch (toupper(*endofnumber)) {
+                        case '\0':
+                                scale = 1;
+                                break;
+                        case 'K':
+                                scale = 1<<10;
+                                break;
+                        case 'M':
+                                scale = 1<<20;
+                                break;
+                        case 'G':
+                                scale = 1<<30;
+                                break;
+                        default:
+                                fatal("%.200s line %d: Invalid RekeyLimit "
+                                    "suffix", filename, linenum);
+                        }
+                        val64 *= scale;
+                        /* detect integer wrap and too-large limits */
+                        if ((val64 / scale) != orig || val64 > UINT_MAX)
+                                fatal("%.200s line %d: RekeyLimit too large",
+                                    filename, linenum);
+                        if (val64 != 0 && val64 < 16)
+                                fatal("%.200s line %d: RekeyLimit too small",
+                                    filename, linenum);
+                }
+                if (*activep && options->rekey_limit == -1)
+                        options->rekey_limit = (u_int32_t)val64;
+                if (cp != NULL) { /* optional rekey interval present */
+                        if (strcmp(cp, "none") == 0) {
+                                (void)strdelim(&cp);    /* discard */
+                                break;
+                        }
+                        intptr = &options->rekey_interval;
+                        goto parse_time;
+                }
+                break;
+
         case sGatewayPorts:
                 intptr = &options->gateway_ports;
                 multistate_ptr = multistate_gatewayports;
@@ -1718,6 +1779,8 @@ copy_set_server_options(ServerOptions *dst, ServerOptions *src, int preauth)
         M_CP_INTOPT(max_authtries);
         M_CP_INTOPT(ip_qos_interactive);
         M_CP_INTOPT(ip_qos_bulk);
+        M_CP_INTOPT(rekey_limit);
+        M_CP_INTOPT(rekey_interval);
 
         /* See comment in servconf.h */
         COPY_MATCH_STRING_OPTS();
@@ -2006,5 +2069,7 @@ dump_config(ServerOptions *o)
         printf("ipqos %s ", iptos2str(o->ip_qos_interactive));
         printf("%s\n", iptos2str(o->ip_qos_bulk));
 
+        printf("rekeylimit %lld %d\n", o->rekey_limit, o->rekey_interval);
+
         channel_print_adm_permitted_opens();
 }