[v5] qemu-ga: Add guest-network-info command

This command returns an array of:

 [ifname, hwaddr, [ipaddr, ipaddr_family, prefix] ]

for each interface in the system.
Currently, only IPv4 and IPv6 are supported.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
---

* Michal Privoznik <mprivozn@redhat.com> [2012-02-28 09:38]:
> This command returns an array of:
> 
>  [ifname, hwaddr, [ipaddr, ipaddr_family, prefix] ]
> 
> for each interface in the system.
> Currently, only IPv4 and IPv6 are supported.


What about vlans and bonding info?

> 
> Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
> ---
> diff to v4:
> -change return type
> 
> diff to v3:
> -use ctpop32() instead of separate count_one_bits()
> 
> diff to v2:
> -Properly set IP addr family for IPv6
> 
> diff to v1:
> -move from guest-getip to guest-network-info
> -replace black boxed algorithm for population count
> -several coding styles improvements
> 
>  qapi-schema-guest.json |   62 +++++++++++++++
>  qga/commands-posix.c   |  197 ++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 259 insertions(+), 0 deletions(-)
> 
> diff --git a/qapi-schema-guest.json b/qapi-schema-guest.json
> index 706925d..41ea2bf 100644
> --- a/qapi-schema-guest.json
> +++ b/qapi-schema-guest.json
> @@ -295,3 +295,65 @@
>  ##
>  { 'command': 'guest-fsfreeze-thaw',
>    'returns': 'int' }
> +
> +##
> +# @GuestIpAddressType:
> +#
> +# An enumeration of supported IP address types
> +#
> +# @ipv4: IP version 4
> +#
> +# @ipv6: IP version 6
> +#
> +# Since: 1.1
> +##
> +{ 'enum': 'GuestIpAddressType',
> +  'data': [ 'ipv4', 'ipv6' ] }
> +
> +##
> +# @GuestIpAddress:
> +#
> +# @ip-address: IP address
> +#
> +# @ip-address-type: Type of @ip-address (e.g. ipv4, ipv6)
> +#
> +# @prefix: Network prefix length of @ip-address
> +#
> +# Since: 1.1
> +##
> +{ 'type': 'GuestIpAddress',
> +  'data': {'ip-address': 'str',
> +           'ip-address-type': 'GuestIpAddressType',
> +           'prefix': 'int'} }
> +
> +##
> +# @GuestNetworkInterface:
> +#
> +# @name: The name of interface for which info are being delivered
> +#
> +# @hardware-address: Hardware address of @name
> +#
> +# @ip-addresses: List of addresses assigned to @name
> +#
> +# Since: 1.1
> +##
> +{ 'type': 'GuestNetworkInterface',
> +  'data': {'name': 'str',
> +           '*hardware-address': 'str',
> +           '*ip-addresses': ['GuestIpAddress'] } }
> +
> +##
> +# @guest-network-info:
> +#
> +# Get list of guest IP addresses, MAC addresses
> +# and netmasks.
> +#
> +# Returns: List of GuestNetworkInfo on success.
> +#
> +# Since: 1.1
> +##
> +{ 'type': 'GuestNetworkInfo',
> +  'data': { 'interfaces': ['GuestNetworkInterface'] } }
> +
> +{ 'command': 'guest-network-info',
> +  'returns': 'GuestNetworkInfo' }
> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> index 126127a..095507b 100644
> --- a/qga/commands-posix.c
> +++ b/qga/commands-posix.c
> @@ -5,6 +5,7 @@
>   *
>   * Authors:
>   *  Michael Roth      <mdroth@linux.vnet.ibm.com>
> + *  Michal Privoznik  <mprivozn@redhat.com>
>   *
>   * This work is licensed under the terms of the GNU GPL, version 2 or later.
>   * See the COPYING file in the top-level directory.
> @@ -23,10 +24,15 @@
> 
>  #include <sys/types.h>
>  #include <sys/ioctl.h>
> +#include <ifaddrs.h>
> +#include <arpa/inet.h>
> +#include <sys/socket.h>
> +#include <net/if.h>
>  #include "qga/guest-agent-core.h"
>  #include "qga-qmp-commands.h"
>  #include "qerror.h"
>  #include "qemu-queue.h"
> +#include "host-utils.h"
> 
>  static GAState *ga_state;
> 
> @@ -526,3 +532,194 @@ void ga_command_state_init(GAState *s, GACommandState *cs)
>  #endif
>      ga_command_state_add(cs, guest_file_init, NULL);
>  }
> +
> +static GuestNetworkInterfaceList *
> +guest_find_interface(GuestNetworkInterfaceList *head,
> +                     const char *name)
> +{
> +    for (; head; head = head->next) {
> +        if (strcmp(head->value->name, name) == 0) {
> +            break;
> +        }
> +    }
> +
> +    return head;
> +}
> +
> +/*
> + * Build information about guest interfaces
> + */
> +static GuestNetworkInterfaceList *guest_build_interfaces_info(Error **errp)
> +{
> +    GuestNetworkInterfaceList *head = NULL, *cur_item = NULL;
> +    struct ifaddrs *ifap, *ifa;
> +    char err_msg[512];
> +
> +    if (getifaddrs(&ifap) < 0) {
> +        snprintf(err_msg, sizeof(err_msg),
> +                 "getifaddrs failed: %s", strerror(errno));
> +        error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
> +        goto error;
> +    }
> +
> +    for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
> +        GuestNetworkInterfaceList *info;
> +        GuestIpAddressList **address_list = NULL, *address_item = NULL;
> +        char addr4[INET_ADDRSTRLEN];
> +        char addr6[INET6_ADDRSTRLEN];
> +        int sock;
> +        struct ifreq ifr;
> +        unsigned char *mac_addr;
> +        void *p;
> +
> +        g_debug("Processing %s interface", ifa->ifa_name);
> +
> +        info = guest_find_interface(head, ifa->ifa_name);
> +
> +        if (!info) {
> +            info = g_malloc0(sizeof(*info));
> +            info->value = g_malloc0(sizeof(*info->value));
> +            info->value->name = g_strdup(ifa->ifa_name);
> +
> +            if (!cur_item) {
> +                head = cur_item = info;
> +            } else {
> +                cur_item->next = info;
> +                cur_item = info;
> +            }
> +        }
> +
> +        if (!info->value->has_hardware_address &&
> +            ifa->ifa_flags & SIOCGIFHWADDR) {
> +            /* we haven't obtained HW address yet */
> +            sock = socket(PF_INET, SOCK_STREAM, 0);
> +            if (sock == -1) {
> +                snprintf(err_msg, sizeof(err_msg),
> +                         "failed to create socket: %s", strerror(errno));
> +                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
> +                goto error;
> +            }
> +
> +            memset(&ifr, 0, sizeof(ifr));
> +            strncpy(ifr.ifr_name,  info->value->name, IF_NAMESIZE);
> +            if (ioctl(sock, SIOCGIFHWADDR, &ifr) == -1) {
> +                snprintf(err_msg, sizeof(err_msg),
> +                         "failed to get MAC addres of %s: %s",
> +                         ifa->ifa_name,
> +                         strerror(errno));
> +                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
> +                goto error;
> +            }
> +
> +            mac_addr = (unsigned char *) &ifr.ifr_hwaddr.sa_data;
> +
> +            if (asprintf(&info->value->hardware_address,
> +                         "%02x:%02x:%02x:%02x:%02x:%02x",
> +                         (int) mac_addr[0], (int) mac_addr[1],
> +                         (int) mac_addr[2], (int) mac_addr[3],
> +                         (int) mac_addr[4], (int) mac_addr[5]) == -1) {
> +                snprintf(err_msg, sizeof(err_msg),
> +                         "failed to format MAC: %s", strerror(errno));
> +                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
> +                goto error;
> +            }
> +
> +            info->value->has_hardware_address = true;
> +            close(sock);
> +        }
> +
> +        if (ifa->ifa_addr &&
> +            ifa->ifa_addr->sa_family == AF_INET) {
> +            /* interface with IPv4 address */
> +            address_item = g_malloc0(sizeof(*address_item));
> +            address_item->value = g_malloc0(sizeof(*address_item->value));
> +            p = &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
> +            if (!inet_ntop(AF_INET, p, addr4, sizeof(addr4))) {
> +                snprintf(err_msg, sizeof(err_msg),
> +                         "inet_ntop failed : %s", strerror(errno));
> +                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
> +                goto error;
> +            }
> +
> +            address_item->value->ip_address = g_strdup(addr4);
> +            address_item->value->ip_address_type = GUEST_IP_ADDRESS_TYPE_IPV4;
> +
> +            if (ifa->ifa_netmask) {
> +                /* Count the number of set bits in netmask.
> +                 * This is safe as '1' and '0' cannot be shuffled in netmask. */
> +                p = &((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr;
> +                address_item->value->prefix = ctpop32(((uint32_t *) p)[0]);
> +            }
> +        } else if (ifa->ifa_addr &&
> +                   ifa->ifa_addr->sa_family == AF_INET6) {
> +            /* interface with IPv6 address */
> +            address_item = g_malloc0(sizeof(*address_item));
> +            address_item->value = g_malloc0(sizeof(*address_item->value));
> +            p = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
> +            if (!inet_ntop(AF_INET6, p, addr6, sizeof(addr6))) {
> +                snprintf(err_msg, sizeof(err_msg),
> +                         "inet_ntop failed : %s", strerror(errno));
> +                error_set(errp, QERR_QGA_COMMAND_FAILED, err_msg);
> +                goto error;
> +            }
> +
> +            address_item->value->ip_address = g_strdup(addr6);
> +            address_item->value->ip_address_type = GUEST_IP_ADDRESS_TYPE_IPV6;
> +
> +            if (ifa->ifa_netmask) {
> +                /* Count the number of set bits in netmask.
> +                 * This is safe as '1' and '0' cannot be shuffled in netmask. */
> +                p = &((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr;
> +                address_item->value->prefix =
> +                    ctpop32(((uint32_t *) p)[0]) +
> +                    ctpop32(((uint32_t *) p)[1]) +
> +                    ctpop32(((uint32_t *) p)[2]) +
> +                    ctpop32(((uint32_t *) p)[3]);
> +            }
> +        }
> +
> +        if (!address_item) {
> +            continue;
> +        }
> +
> +        address_list = &info->value->ip_addresses;
> +
> +        while (*address_list && (*address_list)->next) {
> +            address_list = &(*address_list)->next;
> +        }
> +
> +        if (!*address_list) {
> +            *address_list = address_item;
> +        } else {
> +            (*address_list)->next = address_item;
> +        }
> +
> +        info->value->has_ip_addresses = true;
> +
> +
> +    }
> +
> +    freeifaddrs(ifap);
> +    return head;
> +
> +error:
> +    freeifaddrs(ifap);
> +    qapi_free_GuestNetworkInterfaceList(head);
> +    return NULL;
> +}
> +
> +/*
> + * Get guest network information
> + */
> +GuestNetworkInfo *qmp_guest_network_info(Error **errp)
> +{
> +    GuestNetworkInfo *network_info = NULL;
> +    GuestNetworkInterfaceList *interfaces = guest_build_interfaces_info(errp);
> +
> +    if (interfaces) {
> +        network_info = g_malloc0(sizeof(*network_info));
> +        network_info->interfaces = interfaces;
> +    }
> +
> +    return network_info;
> +}
> -- 
> 1.7.3.4
>