This patch will allow the user to specify classless static routes for
the replies from the built-in DHCP server.
Signed-off-by: Benjamin Drung <benjamin.dr...@profitbricks.com>
---
net/slirp.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++---
qapi/net.json | 4 ++++
qemu-options.hx | 13 +++++++++++-
slirp/bootp.c | 23 ++++++++++++++++++++
slirp/bootp.h | 2 ++
slirp/libslirp.h | 9 +++++++-
slirp/slirp.c | 7 +++++-
slirp/slirp.h | 2 ++
8 files changed, 119 insertions(+), 6 deletions(-)
diff --git a/net/slirp.c b/net/slirp.c
index 8c08e5644f..78df361485 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -158,7 +158,7 @@ static int net_slirp_init(NetClientState *peer, const char
*model,
const char *vnameserver, const char *vnameserver6,
const char *smb_export, const char *vsmbserver,
const char **dnssearch, const char *vdomainname,
- Error **errp)
+ const StringList *vroutes, Error **errp)
{
/* default settings according to historic slirp */
struct in_addr net = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
@@ -177,8 +177,12 @@ static int net_slirp_init(NetClientState *peer, const char
*model,
char buf[20];
uint32_t addr;
int shift;
+ int i = 0;
char *end;
+ unsigned int route_count = 0;
struct slirp_config_str *config;
+ struct StaticRoute *routes = NULL;
+ const StringList *iter;
if (!ipv4 && (vnetwork || vhost || vnameserver)) {
error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
@@ -365,6 +369,58 @@ static int net_slirp_init(NetClientState *peer, const char
*model,
return -1;
}
+ iter = vroutes;
+ while (iter) {
+ route_count++;
+ iter = iter->next;
+ }
+ routes = g_malloc(route_count * sizeof(StaticRoute));
+
+ iter = vroutes;
+ while(iter != NULL) {
+ char buf2[20];
+ const char *gateway = iter->value->str;
+ const char *mask;
+ char *end;
+ long mask_width;
+
+ // Split "subnet/mask:gateway" into its components
+ if (get_str_sep(buf2, sizeof(buf2), &gateway, ':') < 0) {
+ error_setg(errp, "Failed to parse route: No colon found in '%s'",
+ iter->value->str);
+ return -1;
+ }
+ mask = buf2;
+ if (get_str_sep(buf, sizeof(buf), &mask, '/') < 0) {
+ error_setg(errp, "Failed to parse route: No slash found in '%s'",
+ mask);
+ return -1;
+ }
+ if (!inet_aton(buf, &routes[i].subnet)) {
+ error_setg(errp, "Failed to parse route subnet '%s'", buf);
+ return -1;
+ }
+
+ mask_width = strtol(mask, &end, 10);
+ if (*end != '\0') {
+ error_setg(errp,
+ "Failed to parse netmask '%s' (trailing chars)", mask);
+ return -1;
+ } else if (mask_width < 0 || mask_width > 32) {
+ error_setg(errp,
+ "Invalid netmask provided (must be in range 0-32)");
+ return -1;
+ }
+ routes[i].mask_width = (uint8_t)mask_width;
+
+ if (!inet_aton(gateway, &routes[i].gateway)) {
+ error_setg(errp, "Failed to parse route gateway '%s'", gateway);
+ return -1;
+ }
+
+ iter = iter->next;
+ i++;
+ }
nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
@@ -377,7 +433,8 @@ static int net_slirp_init(NetClientState *peer, const char
*model,
s->slirp = slirp_init(restricted, ipv4, net, mask, host,
ipv6, ip6_prefix, vprefix6_len, ip6_host,
vhostname, tftp_export, bootfile, dhcp,
- dns, ip6_dns, dnssearch, vdomainname, s);
+ dns, ip6_dns, dnssearch, vdomainname,
+ route_count, routes, s);
QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
for (config = slirp_configs; config; config = config->next) {
@@ -409,6 +466,7 @@ static int net_slirp_init(NetClientState *peer, const char
*model,
return 0;
error:
+ g_free(routes);
qemu_del_net_client(nc);
return -1;
}
@@ -964,7 +1022,8 @@ int net_init_slirp(const Netdev *netdev, const char *name,
user->ipv6_host, user->hostname, user->tftp,
user->bootfile, user->dhcpstart,
user->dns, user->ipv6_dns, user->smb,
- user->smbserver, dnssearch, user->domainname, errp);
+ user->smbserver, dnssearch, user->domainname,
+ user->route, errp);
while (slirp_configs) {
config = slirp_configs;
diff --git a/qapi/net.json b/qapi/net.json
index 9dfd34cafa..8a85debd92 100644
--- a/qapi/net.json
+++ b/qapi/net.json
@@ -163,6 +163,9 @@
# @domainname: guest-visible domain name of the virtual nameserver
# (since 2.12)
#
+# @route: guest-visible static classless route of the virtual nameserver
+# (since 2.12)
+#
# @ipv6-prefix: IPv6 network prefix (default is fec0::) (since
# 2.6). The network prefix is given in the usual
# hexadecimal IPv6 address notation.
@@ -201,6 +204,7 @@
'*dns': 'str',
'*dnssearch': ['String'],
'*domainname': 'str',
+ '*route': ['String'],
'*ipv6-prefix': 'str',
'*ipv6-prefixlen': 'int',
'*ipv6-host': 'str',
diff --git a/qemu-options.hx b/qemu-options.hx
index c000ef454e..e4bb5919ab 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1907,7 +1907,7 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
" [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
" [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
"
[,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n"
- " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
+ "
[,route=addr/mask:gateway][,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
#ifndef _WIN32
"[,smb=dir[,smbserver=addr]]\n"
#endif
@@ -2119,6 +2119,17 @@ qemu -net
user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
@item domainname=@var{domain}
Specifies the client domain name reported by the built-in DHCP server.
+@item route=@var{addr}/@var{mask}:@var{gateway}
+Provides an entry for the classless static routes list sent by the built-in
+DHCP server. More than one route can be transmitted by specifying
+this option multiple times. If supported, this will cause the guest to
+automatically set the given static routes instead of the given default gateway.
+
+Example:
+@example
+qemu -net user,route=10.0.2.0/24:10.0.2.2,route=192.168.0.0/16:10.0.2.2 [...]
+@end example
+
@item tftp=@var{dir}
When using the user mode network stack, activate a built-in TFTP
server. The files in @var{dir} will be exposed as the root of a TFTP server.
diff --git a/slirp/bootp.c b/slirp/bootp.c
index 9e7b53ba94..a694a43189 100644
--- a/slirp/bootp.c
+++ b/slirp/bootp.c
@@ -306,6 +306,29 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t
*bp)
q += val;
}
+ if (slirp->route_count > 0) {
+ uint8_t option_length = 0;
+ uint8_t significant_octets;
+
+ for (int i = 0; i < slirp->route_count; i++) {
+ significant_octets = slirp->routes[i].mask_width / 8
+ + (slirp->routes[i].mask_width % 8 > 0);
+ option_length += significant_octets + 5;
+ }
+
+ *q++ = RFC3442_CLASSLESS_STATIC_ROUTE;
+ *q++ = option_length;
+ for (int i = 0; i < slirp->route_count; i++) {
+ significant_octets = slirp->routes[i].mask_width / 8
+ + (slirp->routes[i].mask_width % 8 > 0);
+ *q++ = slirp->routes[i].mask_width;
+ memcpy(q, &slirp->routes[i].subnet.s_addr, significant_octets);
+ q += significant_octets;
+ memcpy(q, &slirp->routes[i].gateway.s_addr, 4);
+ q += 4;
+ }
+ }
+
if (slirp->vdnssearch) {
size_t spaceleft = sizeof(rbp->bp_vend) - (q - rbp->bp_vend);
val = slirp->vdnssearch_len;
diff --git a/slirp/bootp.h b/slirp/bootp.h
index 394525733e..60bef4e80d 100644
--- a/slirp/bootp.h
+++ b/slirp/bootp.h
@@ -71,6 +71,8 @@
#define RFC2132_RENEWAL_TIME 58
#define RFC2132_REBIND_TIME 59
+#define RFC3442_CLASSLESS_STATIC_ROUTE 121
+
#define DHCPDISCOVER 1
#define DHCPOFFER 2
#define DHCPREQUEST 3
diff --git a/slirp/libslirp.h b/slirp/libslirp.h
index 740408a96e..3d2e395b08 100644
--- a/slirp/libslirp.h
+++ b/slirp/libslirp.h
@@ -5,6 +5,12 @@
typedef struct Slirp Slirp;
+typedef struct StaticRoute {
+ struct in_addr subnet;
+ uint8_t mask_width;
+ struct in_addr gateway;
+} StaticRoute;
+
int get_dns_addr(struct in_addr *pdns_addr);
int get_dns6_addr(struct in6_addr *pdns6_addr, uint32_t *scope_id);
@@ -16,7 +22,8 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct
in_addr vnetwork,
const char *tftp_path, const char *bootfile,
struct in_addr vdhcp_start, struct in_addr vnameserver,
struct in6_addr vnameserver6, const char **vdnssearch,
- const char *vdomainname, void *opaque);
+ const char *vdomainname, unsigned int routes_count,
+ const StaticRoute *vroutes, void *opaque);
void slirp_cleanup(Slirp *slirp);
void slirp_pollfds_fill(GArray *pollfds, uint32_t *timeout);
diff --git a/slirp/slirp.c b/slirp/slirp.c
index 4f29753444..4e5f249eeb 100644
--- a/slirp/slirp.c
+++ b/slirp/slirp.c
@@ -286,7 +286,8 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct
in_addr vnetwork,
const char *tftp_path, const char *bootfile,
struct in_addr vdhcp_start, struct in_addr vnameserver,
struct in6_addr vnameserver6, const char **vdnssearch,
- const char *vdomainname, void *opaque)
+ const char *vdomainname, unsigned int route_count,
+ const StaticRoute *vroutes, void *opaque)
{
Slirp *slirp = g_malloc0(sizeof(Slirp));
@@ -321,6 +322,9 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct
in_addr vnetwork,
slirp->vdhcp_startaddr = vdhcp_start;
slirp->vnameserver_addr = vnameserver;
slirp->vnameserver_addr6 = vnameserver6;
+ slirp->route_count = route_count;
+ slirp->routes = g_malloc(route_count * sizeof(StaticRoute));
+ memcpy(slirp->routes, vroutes, route_count * sizeof(StaticRoute));
if (vdnssearch) {
translate_dnssearch(slirp, vdnssearch);
@@ -351,6 +355,7 @@ void slirp_cleanup(Slirp *slirp)
g_free(slirp->tftp_prefix);
g_free(slirp->bootp_filename);
g_free(slirp->vdomainname);
+ g_free(slirp->routes);
g_free(slirp);
}
diff --git a/slirp/slirp.h b/slirp/slirp.h
index 10b410898a..3c81b7f7cc 100644
--- a/slirp/slirp.h
+++ b/slirp/slirp.h
@@ -194,6 +194,8 @@ struct Slirp {
size_t vdnssearch_len;
uint8_t *vdnssearch;
char *vdomainname;
+ unsigned int route_count;
+ struct StaticRoute *routes;
/* tcp states */
struct socket tcb;
--
2.14.1
