From: Simon Wunderlich simon@open-mesh.com

This patch adds support for changing the interface alfreds listens to on the fly without restarting alfred.

Signed-off-by: Simon Wunderlich simon@open-mesh.com

--- Changes to PATCH: * fix const warning --- alfred.h | 4 +++- client.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++ main.c | 66 +++++++++++++++++++++++++++++++++++------------------------- man/alfred.8 | 3 +++ packet.h | 17 ++++++++++++++++ unix_sock.c | 38 ++++++++++++++++++++++++++++++++++ vis/vis.c | 2 +- 7 files changed, 155 insertions(+), 29 deletions(-)

diff --git a/alfred.h b/alfred.h index 35ac4dd..c83f7f0 100644 --- a/alfred.h +++ b/alfred.h @@ -86,6 +86,7 @@ enum clientmode { CLIENT_REQUEST_DATA, CLIENT_SET_DATA, CLIENT_MODESWITCH, + CLIENT_CHANGE_INTERFACE, };

struct globals { @@ -93,7 +94,7 @@ struct globals { struct in6_addr address; uint32_t scope_id; struct server *best_server; /* NULL if we are a server ourselves */ - const char *interface; + char *interface; const char *mesh_iface; enum opmode opmode; enum clientmode clientmode; @@ -125,6 +126,7 @@ int set_best_server(struct globals *globals); int alfred_client_request_data(struct globals *globals); int alfred_client_set_data(struct globals *globals); int alfred_client_modeswitch(struct globals *globals); +int alfred_client_change_interface(struct globals *globals); /* recv.c */ int recv_alfred_packet(struct globals *globals); struct transaction_head * diff --git a/client.c b/client.c index b868719..48313db 100644 --- a/client.c +++ b/client.c @@ -22,6 +22,7 @@ #include <ctype.h> #include <errno.h> #include <netinet/in.h> +#include <sys/ioctl.h> #include <stdint.h> #include <stdio.h> #include <string.h> @@ -218,3 +219,56 @@ int alfred_client_modeswitch(struct globals *globals) unix_sock_close(globals); return 0; } + +int alfred_client_change_interface(struct globals *globals) +{ + unsigned char buf[MAX_PAYLOAD]; + struct alfred_change_interface_v0 *change_interface; + struct ifreq ifr; + int ret, len; + int sock = -1; + + if (unix_sock_open_client(globals)) + return -1; + + if (strlen(globals->interface) > IFNAMSIZ) { + fprintf(stderr, "%s: interface name too long, not changing\n", + __func__); + return 0; + } + + sock = socket(PF_INET6, SOCK_DGRAM, 0); + if (sock < 0) { + perror("can't open socket"); + return -1; + } + + strncpy(ifr.ifr_name, globals->interface, IFNAMSIZ); + ifr.ifr_name[IFNAMSIZ - 1] = '\0'; + if (ioctl(sock, SIOCGIFINDEX, &ifr) == -1) { + fprintf(stderr, "%s: can't find interface, not changing\n", + __func__); + close(sock); + return -1; + } + + close(sock); + + change_interface = (struct alfred_change_interface_v0 *)buf; + len = sizeof(*change_interface); + + change_interface->header.type = ALFRED_CHANGE_INTERFACE; + change_interface->header.version = ALFRED_VERSION; + change_interface->header.length = htons(len - sizeof(change_interface->header)); + memcpy(change_interface->iface, globals->interface, + sizeof(change_interface->iface)); + + ret = write(globals->unix_sock, buf, len); + if (ret != len) + fprintf(stderr, "%s: only wrote %d of %d bytes: %s\n", + __func__, ret, len, strerror(errno)); + + unix_sock_close(globals); + + return 0; +} diff --git a/main.c b/main.c index 1add44e..5a4f1e6 100644 --- a/main.c +++ b/main.c @@ -33,25 +33,29 @@ static void alfred_usage(void) { printf("Usage: alfred [options]\n"); printf("client mode options:\n"); - printf(" -s, --set-data [data type] sets new data to distribute from stdin\n"); - printf(" for the supplied data type (0-255)\n"); - printf(" -r, --request [data type] collect data from the network and prints\n"); - printf(" it on the network\n"); - printf(" -V, --req-version specify the data version set for -s\n"); - printf(" -M, --modeswitch master switch daemon to mode master\n"); - printf(" slave switch daemon to mode slave\n"); + printf(" -s, --set-data [data type] sets new data to distribute from stdin\n"); + printf(" for the supplied data type (0-255)\n"); + printf(" -r, --request [data type] collect data from the network and prints\n"); + printf(" it on the network\n"); + printf(" -V, --req-version specify the data version set for -s\n"); + printf(" -M, --modeswitch master switch daemon to mode master\n"); + printf(" slave switch daemon to mode slave\n"); + printf(" -I, --change-interface [interface] change to the specified interface\n"); printf("\n"); printf("server mode options:\n"); - printf(" -i, --interface specify the interface to listen on\n"); - printf(" -b specify the batman-adv interface configured on the system (default: bat0)\n"); - printf(" use 'none' to disable the batman-adv based best server selection\n"); - printf(" -m, --master start up the daemon in master mode, which\n"); - printf(" accepts data from slaves and synces it with\n"); - printf(" other masters\n"); + printf(" -i, --interface specify the interface to listen on\n"); + printf(" -b specify the batman-adv interface\n"); + printf(" configured on the system (default: bat0)\n"); + printf(" use 'none' to disable the batman-adv\n"); + printf(" based best server selection\n"); + printf(" -m, --master start up the daemon in master mode, which\n"); + printf(" accepts data from slaves and synces it with\n"); + printf(" other masters\n"); printf("\n"); - printf(" -u, --unix-path [path] path to unix socket used for client-server communication (default: ""ALFRED_SOCK_PATH_DEFAULT"")\n"); - printf(" -v, --version print the version\n"); - printf(" -h, --help this help\n"); + printf(" -u, --unix-path [path] path to unix socket used for client-server\n"); + printf(" communication (default: ""ALFRED_SOCK_PATH_DEFAULT"")\n"); + printf(" -v, --version print the version\n"); + printf(" -h, --help this help\n"); printf("\n"); }

@@ -60,16 +64,17 @@ static struct globals *alfred_init(int argc, char *argv[]) int opt, opt_ind, i; struct globals *globals; struct option long_options[] = { - {"set-data", required_argument, NULL, 's'}, - {"request", required_argument, NULL, 'r'}, - {"interface", required_argument, NULL, 'i'}, - {"master", no_argument, NULL, 'm'}, - {"help", no_argument, NULL, 'h'}, - {"req-version", required_argument, NULL, 'V'}, - {"modeswitch", required_argument, NULL, 'M'}, - {"unix-path", required_argument, NULL, 'u'}, - {"version", no_argument, NULL, 'v'}, - {NULL, 0, NULL, 0}, + {"set-data", required_argument, NULL, 's'}, + {"request", required_argument, NULL, 'r'}, + {"interface", required_argument, NULL, 'i'}, + {"master", no_argument, NULL, 'm'}, + {"help", no_argument, NULL, 'h'}, + {"req-version", required_argument, NULL, 'V'}, + {"modeswitch", required_argument, NULL, 'M'}, + {"change-interface", required_argument, NULL, 'I'}, + {"unix-path", required_argument, NULL, 'u'}, + {"version", no_argument, NULL, 'v'}, + {NULL, 0, NULL, 0}, };

globals = &alfred_globals; @@ -85,7 +90,7 @@ static struct globals *alfred_init(int argc, char *argv[])

time_random_seed();

- while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:u:", long_options, + while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:", long_options, &opt_ind)) != -1) { switch (opt) { case 'r': @@ -135,6 +140,10 @@ static struct globals *alfred_init(int argc, char *argv[]) } globals->clientmode = CLIENT_MODESWITCH; break; + case 'I': + globals->clientmode = CLIENT_CHANGE_INTERFACE; + globals->interface = strdup(optarg); + break; case 'u': globals->unix_path = optarg; break; @@ -176,6 +185,9 @@ int main(int argc, char *argv[]) case CLIENT_MODESWITCH: return alfred_client_modeswitch(globals); break; + case CLIENT_CHANGE_INTERFACE: + return alfred_client_change_interface(globals); + break; }

return 0; diff --git a/man/alfred.8 b/man/alfred.8 index c90caa8..35dee45 100644 --- a/man/alfred.8 +++ b/man/alfred.8 @@ -80,6 +80,9 @@ to 0 ('\fB-V\fP 0'). \fBslave\fP Switch daemon to mode slave .fi +.TP +\fB-I\fP, \fB--change-interface\fP \fIinterface\fP +Change the alfred server to use the new \fBinterface\fP . .SH SERVER OPTIONS .TP diff --git a/packet.h b/packet.h index ba8c5f6..dc06d65 100644 --- a/packet.h +++ b/packet.h @@ -20,6 +20,8 @@ #ifndef _ALFRED_PACKET_H #define _ALFRED_PACKET_H

+#include <net/if.h> /* IFNAMSIZ */ + #define __packed __attribute__ ((packed))

/* basic blocks */ @@ -67,6 +69,7 @@ struct alfred_transaction_mgmt { * @ALFRED_STATUS_TXEND: Transaction was finished by sender * @ALFRED_STATUS_ERROR: Error was detected during the transaction * @ALFRED_MODESWITCH: Switch between different operation modes + * @ALFRED_CHANGE_INTERFACE: Change the listening interface */ enum alfred_packet_type { ALFRED_PUSH_DATA = 0, @@ -75,6 +78,7 @@ enum alfred_packet_type { ALFRED_STATUS_TXEND = 3, ALFRED_STATUS_ERROR = 4, ALFRED_MODESWITCH = 5, + ALFRED_CHANGE_INTERFACE = 6, };

/* packets */ @@ -143,6 +147,19 @@ struct alfred_modeswitch_v0 { } __packed;

/** + * struct alfred_change_interface_v0 - Request to change the interface + * @header: TLV header describing the complete packet + * @iface: interface name to be changed to + * + * Sent to the daemon by client + */ +struct alfred_change_interface_v0 { + struct alfred_tlv header; + char iface[IFNAMSIZ]; +} __packed; + + +/** * struct alfred_status_v0 - Status info of a transaction * @header: TLV header describing the complete packet * @tx: Transaction identificator and sequence number of packet diff --git a/unix_sock.c b/unix_sock.c index cc0d25c..516c0a5 100644 --- a/unix_sock.c +++ b/unix_sock.c @@ -298,6 +298,38 @@ err: return ret; }

+static int +unix_sock_change_iface(struct globals *globals, + struct alfred_change_interface_v0 *change_iface, + int client_sock) +{ + int len, ret = -1; + char *iface; + + len = ntohs(change_iface->header.length); + + if (len < (int)(sizeof(*change_iface) - sizeof(change_iface->header))) + goto err; + + iface = malloc(IFNAMSIZ + 1); + if (!iface) + goto err; + + memcpy(iface, change_iface->iface, IFNAMSIZ); + iface[IFNAMSIZ] = 0; + + netsock_close(globals->netsock); + + free(globals->interface); + globals->interface = iface; + netsock_open(globals); + + ret = 0; +err: + close(client_sock); + return ret; +} + int unix_sock_read(struct globals *globals) { int client_sock; @@ -350,6 +382,12 @@ int unix_sock_read(struct globals *globals) (struct alfred_modeswitch_v0 *)packet, client_sock); break; + case ALFRED_CHANGE_INTERFACE: + ret = unix_sock_change_iface(globals, + (struct alfred_change_interface_v0 *)packet, + client_sock); + break; + default: /* unknown packet type */ ret = -1; diff --git a/vis/vis.c b/vis/vis.c index 00372ab..3dd5c8c 100644 --- a/vis/vis.c +++ b/vis/vis.c @@ -23,7 +23,7 @@ #include <dirent.h> #include <errno.h> #include <getopt.h> -#include <linux/if.h> +#include <net/if.h> #include <netinet/in.h> #include <signal.h> #include <stdbool.h>