RE: [PATCH 3/3] net/colo-compare: Add handler for passthrough connection

["Zhang, Chen" <chen.zhang@intel.com>]

> -----Original Message-----
> From: Lukas Straub <lukasstraub2@web.de>
> Sent: Thursday, January 14, 2021 9:51 PM
> To: Zhang, Chen <chen.zhang@intel.com>
> Cc: Jason Wang <jasowang@redhat.com>; qemu-dev <qemu-
> devel@nongnu.org>; Eric Blake <eblake@redhat.com>; Dr. David Alan
> Gilbert <dgilbert@redhat.com>; Markus Armbruster <armbru@redhat.com>;
> Zhang Chen <zhangckid@gmail.com>
> Subject: Re: [PATCH 3/3] net/colo-compare: Add handler for passthrough
> connection
> 
> On Thu, 24 Dec 2020 09:09:18 +0800
> Zhang Chen <chen.zhang@intel.com > wrote:
> 
> > From: Zhang Chen <chen.zhang@intel.com>
> >
> > Currently, we just use guest's TCP/UDP source port as the key to
> > bypass certain network traffic.
> >
> > Signed-off-by: Zhang Chen <chen.zhang@intel.com>
> > ---
> >  net/colo-compare.c | 49
> > ++++++++++++++++++++++++++++++++++++++++++++++
> >  net/colo-compare.h |  2 ++
> >  net/net.c          | 27 +++++++++++++++++++++++++
> >  3 files changed, 78 insertions(+)
> >
> > diff --git a/net/colo-compare.c b/net/colo-compare.c index
> > 337025b44f..11a32caa9b 100644
> > --- a/net/colo-compare.c
> > +++ b/net/colo-compare.c
> > @@ -46,6 +46,9 @@ static QTAILQ_HEAD(, CompareState) net_compares =
> > static NotifierList colo_compare_notifiers =
> >      NOTIFIER_LIST_INITIALIZER(colo_compare_notifiers);
> >
> > +static QLIST_HEAD(, PassthroughEntry) passthroughlist =
> > +    QLIST_HEAD_INITIALIZER(passthroughlist);
> > +
> >  #define COMPARE_READ_LEN_MAX NET_BUFSIZE  #define
> MAX_QUEUE_SIZE 1024
> >
> > @@ -103,6 +106,12 @@ typedef struct SendEntry {
> >      uint8_t *buf;
> >  } SendEntry;
> >
> > +typedef struct PassthroughEntry {
> > +    bool is_tcp;
> > +    uint16_t port;
> > +    QLIST_ENTRY(PassthroughEntry) node; } PassthroughEntry;
> > +
> >  struct CompareState {
> >      Object parent;
> >
> > @@ -247,6 +256,7 @@ static int packet_enqueue(CompareState *s, int
> mode, Connection **con)
> >      ConnectionKey key;
> >      Packet *pkt = NULL;
> >      Connection *conn;
> > +    PassthroughEntry *bypass, *next;
> >      int ret;
> >
> >      if (mode == PRIMARY_IN) {
> > @@ -264,8 +274,23 @@ static int packet_enqueue(CompareState *s, int
> mode, Connection **con)
> >          pkt = NULL;
> >          return -1;
> >      }
> > +
> >      fill_connection_key(pkt, &key);
> >
> > +    /* Check COLO passthrough connenction */
> > +    if (!QLIST_EMPTY(&passthroughlist)) {
> > +        QLIST_FOREACH_SAFE(bypass, &passthroughlist, node, next) {
> > +            if (((key.ip_proto == IPPROTO_TCP) && bypass->is_tcp) ||
> > +                ((key.ip_proto == IPPROTO_UDP) && !bypass->is_tcp)) {
> > +                if (bypass->port == key.src_port) {
> > +                    packet_destroy(pkt, NULL);
> > +                    pkt = NULL;
> > +                    return -1;
> > +                }
> > +            }
> > +        }
> > +    }
> > +
> >      conn = connection_get(s->connection_track_table,
> >                            &key,
> >                            &s->conn_list); @@ -1373,6 +1398,30 @@
> > static void colo_flush_packets(void *opaque, void *user_data)
> >      }
> >  }
> >
> > +void colo_compare_passthrough_add(bool is_tcp, const uint16_t port) {
> > +    PassthroughEntry *bypass = NULL;
> > +
> > +    bypass = g_new0(PassthroughEntry, 1);
> > +    bypass->is_tcp = is_tcp;
> > +    bypass->port = port;
> > +    QLIST_INSERT_HEAD(&passthroughlist, bypass, node); }
> > +
> > +void colo_compare_passthrough_del(bool is_tcp, const uint16_t port) {
> > +    PassthroughEntry *bypass = NULL, *next = NULL;
> > +
> > +    if (!QLIST_EMPTY(&passthroughlist)) {
> > +        QLIST_FOREACH_SAFE(bypass, &passthroughlist, node, next) {
> > +            if ((bypass->is_tcp == is_tcp) && (bypass->port == port)) {
> > +                QLIST_REMOVE(bypass, node);
> > +                g_free(bypass);
> > +            }
> > +        }
> > +    }
> > +}
> > +
> 
> Access to "passtroughlist" needs to be protected by a lock, as
> "packet_enqueue" is called from a different iothread.

OK, I will add the lock in next version.

Thanks
Chen

> 
> >  static void colo_compare_class_init(ObjectClass *oc, void *data)  {
> >      UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); diff --git
> > a/net/colo-compare.h b/net/colo-compare.h index
> 22ddd512e2..1fa026c85e
> > 100644
> > --- a/net/colo-compare.h
> > +++ b/net/colo-compare.h
> > @@ -20,5 +20,7 @@
> >  void colo_notify_compares_event(void *opaque, int event, Error
> > **errp);  void colo_compare_register_notifier(Notifier *notify);  void
> > colo_compare_unregister_notifier(Notifier *notify);
> > +void colo_compare_passthrough_add(bool is_tcp, const uint16_t port);
> > +void colo_compare_passthrough_del(bool is_tcp, const uint16_t port);
> >
> >  #endif /* QEMU_COLO_COMPARE_H */
> > diff --git a/net/net.c b/net/net.c
> > index eac7a92618..1f303e8309 100644
> > --- a/net/net.c
> > +++ b/net/net.c
> > @@ -55,6 +55,7 @@
> >  #include "sysemu/sysemu.h"
> >  #include "net/filter.h"
> >  #include "qapi/string-output-visitor.h"
> > +#include "net/colo-compare.h"
> >
> >  /* Net bridge is currently not supported for W32. */  #if
> > !defined(_WIN32) @@ -1155,12 +1156,38 @@ void
> > qmp_colo_passthrough_add(const char *prot, const uint32_t port,
> >                                Error **errp)  {
> >      /* Setup passthrough connection */
> > +    if (port > 65536) {
> > +        error_setg(errp, "COLO pass through get wrong port");
> > +        return;
> > +    }
> > +
> > +    if (!strcmp(prot, "tcp") || !strcmp(prot, "TCP")) {
> > +        colo_compare_passthrough_add(true, (uint16_t)port);
> > +    } else if (!strcmp(prot, "udp") || !strcmp(prot, "UDP")) {
> > +        colo_compare_passthrough_add(false, (uint16_t)port);
> > +    } else {
> > +        error_setg(errp, "COLO pass through just support tcp or udp
> protocol");
> > +        return;
> > +    }
> >  }
> >
> >  void qmp_colo_passthrough_del(const char *prot, const uint32_t port,
> >                                Error **errp)  {
> >      /* Delete passthrough connection */
> > +    if (port > 65536) {
> > +        error_setg(errp, "COLO pass through get wrong port");
> > +        return;
> > +    }
> > +
> > +    if (!strcmp(prot, "tcp") || !strcmp(prot, "TCP")) {
> > +        colo_compare_passthrough_del(true, (uint16_t)port);
> > +    } else if (!strcmp(prot, "udp") || !strcmp(prot, "UDP")) {
> > +        colo_compare_passthrough_del(false, (uint16_t)port);
> > +    } else {
> > +        error_setg(errp, "COLO pass through just support tcp or udp
> protocol");
> > +        return;
> > +    }
> >  }
> >
> >  static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
> 
> 
> 
> --