Re: [Qemu-devel] [PATCH v5 1/2] slirp: Add "query-usernet" QMP command

["Daniel P. Berrangé" <berrange@redhat.com>]

On Thu, May 03, 2018 at 09:25:45AM +0800, Fam Zheng wrote:
> HMP "info usernet" has been available but it isn't ideal for programmed
> use cases. This closes the gap in QMP by adding a counterpart
> "query-usernet" command. It is basically translated from
> the HMP slirp_connection_info() loop, which now calls the QMP
> implementation and prints the data, just like other HMP info_* commands.
> 
> The TCPS_* macros are now defined as a QAPI enum.
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>


> diff --git a/qapi/net.json b/qapi/net.json
> index 9117c56972..83757d0ed0 100644
> --- a/qapi/net.json
> +++ b/qapi/net.json
> @@ -689,3 +689,217 @@
>  ##
>  { 'event': 'NIC_RX_FILTER_CHANGED',
>    'data': { '*name': 'str', 'path': 'str' } }
> +
> +##
> +# @TCPS:
> +#
> +# TCP States of a SLIRP connection.
> +#
> +# - States where connections are not established: none, closed, listen, syn-sent,
> +#   syn-received
> +#
> +# - States where user has closed: fin-wait-1, closing, last-ack, fin-wait-2,
> +#   time-wait
> +#
> +# - States awaiting ACK of FIN: fin-wait-1, closing, last-ack
> +#
> +# 'none' state is used only when host forwarding
> +#
> +# Since 2.13
> +#
> +##
> +{ 'enum': 'TCPS',

I'd suggest avoiding the abbreviation, IOW use  TCPState as
the name. Yes that will require changnig the constants in
the SLIRP code, but that's worthwhile to get this QAPI
naming clearer IMHO.

I wonder if we should have a common prefix too eg UsernetTCPState
as this is a global QAPI namespace after all .

> +  'data':
> +   ['closed',
> +    'listen',
> +    'syn-sent',
> +    'syn-received',
> +    'established',
> +    'close-wait',
> +    'fin-wait-1',
> +    'closing',
> +    'last-ack',
> +    'fin-wait-2',
> +    'time-wait',
> +    'none'
> +   ] }
> +
> +##
> +# @UsernetTCPConnection:
> +#
> +# SLIRP TCP information.
> +#
> +# @state: tcp connection state
> +#
> +# @hostfwd: whether this connection has host port forwarding
> +#
> +# @fd: the file descriptor of the connection
> +#
> +# @src-addr: source address of host port forwarding
> +#
> +# @src-port: source port of host port forwarding
> +#
> +# @dest-addr: destination address of host port forwarding
> +#
> +# @dest-port: destination port of host port forwarding
> +#
> +# @recv-buffered: number of bytes queued in the receive buffer
> +#
> +# @send-buffered: number of bytes queued in the send buffer
> +#
> +# Since: 2.13
> +##
> +{ 'struct': 'UsernetTCPConnection',
> +  'data': {
> +    'state': 'TCPS',
> +    'hostfwd': 'bool',
> +    'fd': 'int',
> +    'src-addr': 'str',
> +    'src-port': 'int',
> +    'dest-addr': 'str',
> +    'dest-port': 'int',
> +    'recv-buffered': 'int',
> +    'send-buffered': 'int'
> +  } }
> +
> +##
> +# @UsernetUDPConnection:
> +#
> +# SLIRP UDP information.
> +#
> +# @hostfwd: whether this connection has host port forwarding
> +#
> +# @expire-time-ms: time in microseconds after which this connection will expire
> +#
> +# @fd: the file descriptor of the connection
> +#
> +# @src-addr: source address of host port forwarding
> +#
> +# @src-port: source port of host port forwarding
> +#
> +# @dest-addr: destination address of host port forwarding
> +#
> +# @dest-port: destination port of host port forwarding
> +#
> +# @recv-buffered: number of bytes queued in the receive buffer
> +#
> +# @send-buffered: number of bytes queued in the send buffer
> +#
> +# Since: 2.13
> +##
> +{ 'struct': 'UsernetUDPConnection',
> +  'data': {
> +    'hostfwd': 'bool',
> +    'expire-time-ms': 'int',
> +    'fd': 'int',
> +    'src-addr': 'str',
> +    'src-port': 'int',
> +    'dest-addr': 'str',
> +    'dest-port': 'int',
> +    'recv-buffered': 'int',
> +    'send-buffered': 'int'
> +    } }
> +
> +##
> +# @UsernetICMPConnection:
> +#
> +# SLIRP ICMP information.
> +#
> +# @expire-time-ms: time in microseconds after which this connection will expire
> +#
> +# @fd: the file descriptor of the connection
> +#
> +# @src-addr: source address of host port forwarding
> +#
> +# @dest-addr: destination address of host port forwarding
> +#
> +# @recv-buffered: number of bytes queued in the receive buffer
> +#
> +# @send-buffered: number of bytes queued in the send buffer
> +#
> +# Since: 2.13
> +##
> +{ 'struct': 'UsernetICMPConnection',
> +  'data': {
> +    'expire-time-ms': 'int',
> +    'fd': 'int',
> +    'src-addr': 'str',
> +    'dest-addr': 'str',
> +    'recv-buffered': 'int',
> +    'send-buffered': 'int'
> +    } }
> +
> +##
> +# @UsernetType:
> +#
> +# Available netdev drivers.
> +#
> +# Since: 2.13
> +##
> +{ 'enum': 'UsernetType',
> +  'data': [ 'tcp', 'udp', 'icmp' ] }
> +
> +##
> +# @UsernetConnection:
> +#
> +# SLIRP usernet connection information.
> +#
> +# Since: 2.13
> +##
> +{ 'union': 'UsernetConnection',
> +  'discriminator': 'type',
> +  'base': { 'type': 'UsernetType' },
> +  'data': {
> +    'tcp':     'UsernetTCPConnection',
> +    'udp':     'UsernetUDPConnection',
> +    'icmp':    'UsernetICMPConnection'
> +    } }
> +
> +##
> +# @UsernetInfo:
> +#
> +# SLIRP usernet information.
> +#
> +# Since: 2.13
> +##
> +{ 'struct': 'UsernetInfo',
> +  'data': {
> +    'id':              'str',
> +    'hub':             'int',
> +    'connections':     ['UsernetConnection']
> +} }
> +
> +##
> +# @query-usernet:
> +#
> +# Return SLIRP network information.
> +#
> +# Since: 2.13
> +#
> +# Example:
> +#
> +# -> { "execute": "query-usernet", "arguments": { } }
> +# <- { "return": [
> +#      {
> +#        "hub": -1,
> +#        "connections": [
> +#          {
> +#            "dest-addr": "10.0.2.15",
> +#            "recv-buffered": 0,
> +#            "src-port": 10022,
> +#            "state": "closed",
> +#            "fd": 16,
> +#            "src-addr": "*",
> +#            "send-buffered": 0,
> +#            "dest-port": 22,
> +#            "type": "tcp",
> +#            "hostfwd": true
> +#          }
> +#        ],
> +#        "id": "vnet"
> +#      }
> +#   ]}
> +#
> +##
> +{ 'command': 'query-usernet',
> +  'returns': ['UsernetInfo'] }
> diff --git a/slirp/libslirp.h b/slirp/libslirp.h
> index 540b3e5903..3ba361ea41 100644
> --- a/slirp/libslirp.h
> +++ b/slirp/libslirp.h
> @@ -2,6 +2,7 @@
>  #define LIBSLIRP_H
>  
>  #include "qemu-common.h"
> +#include "qapi/qapi-commands-net.h"
>  
>  typedef struct Slirp Slirp;
>  
> @@ -37,6 +38,7 @@ int slirp_add_exec(Slirp *slirp, int do_pty, const void *args,
>                     struct in_addr *guest_addr, int guest_port);
>  
>  void slirp_connection_info(Slirp *slirp, Monitor *mon);
> +void usernet_get_info(Slirp *slirp, UsernetInfo *info);
>  
>  void slirp_socket_recv(Slirp *slirp, struct in_addr guest_addr,
>                         int guest_port, const uint8_t *buf, int size);
> diff --git a/slirp/misc.c b/slirp/misc.c
> index 260187b6b6..335b49aad8 100644
> --- a/slirp/misc.c
> +++ b/slirp/misc.c
> @@ -205,39 +205,28 @@ fork_exec(struct socket *so, const char *ex, int do_pty)
>  }
>  #endif
>  
> -void slirp_connection_info(Slirp *slirp, Monitor *mon)
> +void usernet_get_info(Slirp *slirp, UsernetInfo *info)
>  {
> -    const char * const tcpstates[] = {
> -        [TCPS_CLOSED]       = "CLOSED",
> -        [TCPS_LISTEN]       = "LISTEN",
> -        [TCPS_SYN_SENT]     = "SYN_SENT",
> -        [TCPS_SYN_RECEIVED] = "SYN_RCVD",
> -        [TCPS_ESTABLISHED]  = "ESTABLISHED",
> -        [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
> -        [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
> -        [TCPS_CLOSING]      = "CLOSING",
> -        [TCPS_LAST_ACK]     = "LAST_ACK",
> -        [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
> -        [TCPS_TIME_WAIT]    = "TIME_WAIT",
> -    };
>      struct in_addr dst_addr;
>      struct sockaddr_in src;
>      socklen_t src_len;
>      uint16_t dst_port;
>      struct socket *so;
> -    const char *state;
> -    char buf[20];
> -
> -    monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
> -                        "Dest. Address  Port RecvQ SendQ\n");
> +    UsernetConnectionList **p_next = &info->connections;
>  
>      for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
> +        UsernetConnection *conn = g_new0(UsernetConnection, 1);
> +        UsernetTCPConnection *tcp = &conn->u.tcp;
> +        UsernetConnectionList *list = g_new0(UsernetConnectionList, 1);
> +
> +        list->value = conn;
>          if (so->so_state & SS_HOSTFWD) {
> -            state = "HOST_FORWARD";
> +            tcp->hostfwd = true;
> +            tcp->state = so->so_tcpcb->t_state;
>          } else if (so->so_tcpcb) {
> -            state = tcpstates[so->so_tcpcb->t_state];
> +            tcp->state = so->so_tcpcb->t_state;
>          } else {
> -            state = "NONE";
> +            tcp->state = TCPS_NONE;
>          }
>          if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
>              src_len = sizeof(src);
> @@ -250,46 +239,125 @@ void slirp_connection_info(Slirp *slirp, Monitor *mon)
>              dst_addr = so->so_faddr;
>              dst_port = so->so_fport;
>          }
> -        snprintf(buf, sizeof(buf), "  TCP[%s]", state);
> -        monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
> -                       src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
> -                       ntohs(src.sin_port));
> -        monitor_printf(mon, "%15s %5d %5d %5d\n",
> -                       inet_ntoa(dst_addr), ntohs(dst_port),
> -                       so->so_rcv.sb_cc, so->so_snd.sb_cc);
> +        tcp->fd = so->s;
> +        tcp->src_addr =
> +            g_strdup(src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
> +        tcp->src_port = ntohs(src.sin_port);
> +        tcp->dest_addr = g_strdup(inet_ntoa(dst_addr));
> +        tcp->dest_port = ntohs(dst_port);
> +        tcp->recv_buffered = so->so_rcv.sb_cc;
> +        tcp->send_buffered = so->so_snd.sb_cc;
> +        *p_next = list;
> +        p_next = &list->next;
>      }
> -
>      for (so = slirp->udb.so_next; so != &slirp->udb; so = so->so_next) {
> +        UsernetConnection *conn = g_new0(UsernetConnection, 1);
> +        UsernetUDPConnection *udp = &conn->u.udp;
> +        UsernetConnectionList *list = g_new0(UsernetConnectionList, 1);
> +
> +        list->value = conn;
>          if (so->so_state & SS_HOSTFWD) {
> -            snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
> +            udp->hostfwd = true;
>              src_len = sizeof(src);
>              getsockname(so->s, (struct sockaddr *)&src, &src_len);
>              dst_addr = so->so_laddr;
>              dst_port = so->so_lport;
>          } else {
> -            snprintf(buf, sizeof(buf), "  UDP[%d sec]",
> -                         (so->so_expire - curtime) / 1000);
> +            udp->expire_time_ms = so->so_expire - curtime;
>              src.sin_addr = so->so_laddr;
>              src.sin_port = so->so_lport;
>              dst_addr = so->so_faddr;
>              dst_port = so->so_fport;
>          }
> -        monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
> -                       src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
> -                       ntohs(src.sin_port));
> -        monitor_printf(mon, "%15s %5d %5d %5d\n",
> -                       inet_ntoa(dst_addr), ntohs(dst_port),
> -                       so->so_rcv.sb_cc, so->so_snd.sb_cc);
> +        udp->fd = so->s;
> +        udp->src_addr =
> +            g_strdup(src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
> +        udp->src_port = ntohs(src.sin_port);
> +        udp->dest_addr = g_strdup(inet_ntoa(dst_addr));
> +        udp->dest_port = ntohs(dst_port);
> +        udp->recv_buffered = so->so_rcv.sb_cc;
> +        udp->send_buffered = so->so_snd.sb_cc;
> +        *p_next = list;
> +        p_next = &list->next;
>      }
>  
>      for (so = slirp->icmp.so_next; so != &slirp->icmp; so = so->so_next) {
> -        snprintf(buf, sizeof(buf), "  ICMP[%d sec]",
> -                     (so->so_expire - curtime) / 1000);
> +        UsernetConnection *conn = g_new0(UsernetConnection, 1);
> +        UsernetICMPConnection *icmp = &conn->u.icmp;
> +        UsernetConnectionList *list = g_new0(UsernetConnectionList, 1);
> +
> +        icmp->expire_time_ms = so->so_expire - curtime;
>          src.sin_addr = so->so_laddr;
>          dst_addr = so->so_faddr;
> -        monitor_printf(mon, "%-19s %3d %15s  -    ", buf, so->s,
> -                       src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
> -        monitor_printf(mon, "%15s  -    %5d %5d\n", inet_ntoa(dst_addr),
> -                       so->so_rcv.sb_cc, so->so_snd.sb_cc);
> +        icmp->fd = so->s;
> +        icmp->src_addr =
> +            g_strdup(src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
> +        icmp->dest_addr = g_strdup(inet_ntoa(dst_addr));
> +        icmp->recv_buffered = so->so_rcv.sb_cc;
> +        icmp->send_buffered = so->so_snd.sb_cc;
> +        *p_next = list;
> +        p_next = &list->next;
>      }
>  }
> +
> +
> +void slirp_connection_info(Slirp *slirp, Monitor *mon)
> +{
> +    const char *state;
> +    char buf[64];
> +    UsernetInfo *info = g_new0(UsernetInfo, 1);
> +    UsernetConnectionList *cl;
> +
> +    monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
> +                        "Dest. Address  Port RecvQ SendQ\n");
> +
> +    usernet_get_info(slirp, info);
> +    for (cl = info->connections; cl && cl->value; cl = cl->next) {
> +        UsernetConnection *conn = cl->value;
> +
> +        if (conn->type == USERNET_TYPE_TCP) {
> +            UsernetTCPConnection *tcp = &conn->u.tcp;
> +
> +            if (tcp->hostfwd) {
> +                state = "HOST_FORWARD";
> +            } else {
> +                state = TCPS_str(tcp->state);
> +            }
> +            snprintf(buf, sizeof(buf), "  TCP[%s]", state);
> +            monitor_printf(mon, "%-19s %3" PRId64 " %15s %5" PRId64 " ",
> +                           buf, tcp->fd,
> +                           tcp->src_addr, tcp->src_port);
> +            monitor_printf(mon, "%15s %5" PRId64 " %5" PRId64 " %5" PRId64 "\n",
> +                           tcp->dest_addr, tcp->dest_port,
> +                           tcp->recv_buffered, tcp->send_buffered);
> +        } else if (conn->type == USERNET_TYPE_UDP) {
> +            UsernetUDPConnection *udp = &conn->u.udp;
> +
> +            if (udp->hostfwd) {
> +                snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
> +            } else {
> +                snprintf(buf, sizeof(buf), "  UDP[%" PRId64 " sec]",
> +                         udp->expire_time_ms / 1000);
> +            }
> +            monitor_printf(mon, "%-19s %3" PRId64 " %15s %5" PRId64 " ",
> +                           buf, udp->fd,
> +                           udp->src_addr, udp->src_port);
> +            monitor_printf(mon, "%15s %5" PRId64 " %5" PRId64 " %5" PRId64 "\n",
> +                           udp->dest_addr, udp->dest_port,
> +                           udp->recv_buffered, udp->send_buffered);
> +        } else {
> +            UsernetICMPConnection *icmp = &conn->u.icmp;
> +
> +            assert(conn->type == USERNET_TYPE_ICMP);
> +            snprintf(buf, sizeof(buf), "  ICMP[%" PRId64 " sec]",
> +                     icmp->expire_time_ms / 1000);
> +            monitor_printf(mon, "%-19s %3" PRId64 " %15s  -    ", buf, icmp->fd,
> +                           icmp->src_addr);
> +            monitor_printf(mon, "%15s  -    %5" PRId64 " %5" PRId64 "\n",
> +                           icmp->dest_addr,
> +                           icmp->recv_buffered, icmp->send_buffered);
> +        }
> +    }
> +
> +    qapi_free_UsernetInfo(info);
> +}
> diff --git a/slirp/tcp.h b/slirp/tcp.h
> index 174d3d960c..155569f380 100644
> --- a/slirp/tcp.h
> +++ b/slirp/tcp.h
> @@ -133,21 +133,6 @@ struct tcphdr {
>  
>  #define TCP_NSTATES     11
>  
> -#define TCPS_CLOSED             0       /* closed */
> -#define TCPS_LISTEN             1       /* listening for connection */
> -#define TCPS_SYN_SENT           2       /* active, have sent syn */
> -#define TCPS_SYN_RECEIVED       3       /* have send and received syn */
> -/* states < TCPS_ESTABLISHED are those where connections not established */
> -#define TCPS_ESTABLISHED        4       /* established */
> -#define TCPS_CLOSE_WAIT         5       /* rcvd fin, waiting for close */
> -/* states > TCPS_CLOSE_WAIT are those where user has closed */
> -#define TCPS_FIN_WAIT_1         6       /* have closed, sent fin */
> -#define TCPS_CLOSING            7       /* closed xchd FIN; await FIN ACK */
> -#define TCPS_LAST_ACK           8       /* had fin and close; await FIN ACK */
> -/* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
> -#define TCPS_FIN_WAIT_2         9       /* have closed, fin is acked */
> -#define TCPS_TIME_WAIT          10      /* in 2*msl quiet wait after close */
> -
>  #define TCPS_HAVERCVDSYN(s)     ((s) >= TCPS_SYN_RECEIVED)
>  #define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED)
>  #define TCPS_HAVERCVDFIN(s)     ((s) >= TCPS_TIME_WAIT)
> -- 
> 2.14.3
> 
> 

Regards,
Daniel
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