* update todo list

* add avvahi-dnsconfd
* implement AvahiDNSServerBrowser
* Update special browse/register RRs to match current RFC
* add support to avahi-daemon to publish name server information
* add support to avahi-daemon to publish /etc/resolv.conf DNS server information
* add new simple protocol command: "BROWSE-DNS-SERVERS"
* cleanup final configure message


git-svn-id: file:///home/lennart/svn/public/avahi/trunk@143 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe

3 files changed, 721 insertions, 0 deletions

diff --git a/avahi-dnsconfd/Makefile.am b/avahi-dnsconfd/Makefile.am
new file mode 100644
index 0000000..8a0787a
--- /dev/null
+++ b/avahi-dnsconfd/Makefile.am
@@ -0,0 +1,51 @@
+# $Id$
+#
+# This file is part of avahi.
+# 
+# avahi is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation; either version 2 of the
+# License, or (at your option) any later version.
+#
+# avahi is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+# License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with avahi; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+# USA.
+
+pkgsysconfdir=$(sysconfdir)/avahi
+
+AM_CFLAGS= \
+	-I$(top_srcdir) \
+	-D_GNU_SOURCE \
+	-DAVAHI_DNSCONF_SCRIPT=\"$(pkgsysconfdir)/dnsconf.action\" \
+	-DAVAHI_SOCKET=\"$(localstatedir)/run/avahi/socket\" \
+	-DAVAHI_RUNTIME_DIR=\"$(localstatedir)/run\"
+
+# GLIB 2.0
+AM_CFLAGS+=$(GLIB20_CFLAGS)
+AM_LDADD=$(GLIB20_LIBS)
+
+# libdaemon
+AM_CFLAGS+=$(LIBDAEMON_CFLAGS)
+AM_LDADD+=$(LIBDAEMON_LIBS)
+
+# This cool debug trap works on i386/gcc only
+AM_CFLAGS+='-DDEBUG_TRAP=__asm__("int $$3")'
+
+bin_PROGRAMS = \
+	avahi-dnsconfd
+
+avahi_dnsconfd_SOURCES = \
+	main.c main.h
+
+avahi_dnsconfd_CFLAGS = $(AM_CFLAGS)
+avahi_dnsconfd_LDADD = $(AM_LDADD) ../avahi-common/libavahi-common.la
+
+pkgsysconf_DATA=dnsconf.action
+
+EXTRA_DIST=dnsconf.action
diff --git a/avahi-dnsconfd/dnsconf.action b/avahi-dnsconfd/dnsconf.action
new file mode 100755
index 0000000..9337a6d
--- /dev/null
+++ b/avahi-dnsconfd/dnsconf.action
@@ -0,0 +1,62 @@
+#!/bin/sh
+
+# $Id$
+#
+# This file is part of avahi.
+# 
+# avahi is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation; either version 2 of the
+# License, or (at your option) any later version.
+#
+# avahi is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+# License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with avahi; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+# USA.
+
+set -e
+
+test "x$AVAHI_INTERFACE" != "x"
+
+# Command line arguments:
+#   $1 "+" if a new DNS server was found, "-" if one was removed
+#   $2 DNS Server address
+#   $3 interface index where this server was found on
+#   $4 protocol number where this server was found on
+
+# Available environment variables:
+#
+#   $AVAHI_INTERFACE               The interface name where this DNS server was found on
+#   $AVAHI_INTERFACE_DNS_SERVERS   A whitespace seperated list of DNS servers on $AVAHI_INTERFACE
+#   $AVAHI_DNS_SERVERS             The complete list of all DNS servers found on all interfaces
+
+if [ -x /sbin/resolvconf ] ; then
+
+    # We have Debian's resolvconf tool
+
+    if [ "x$AVAHI_INTERFACE_DNS_SERVERS" = "x" ] ; then
+        /sbin/resolvconf -d "$AVAHI_INTERFACE.avahi"
+    else
+        for n in $AVAHI_INTERFACE_DNS_SERVERS ; do 
+            echo "nameserver $n"
+        done | /sbin/resolvconf -a "$AVAHI_INTERFACE.avahi"
+    fi
+else
+
+    # No resolvconf tool available
+
+    if [ "x$AVAHI_DNS_SERVERS" = "x" ] ; then
+        test -f /etc/resolv.conf.avahi && mv /etc/resolv.conf.avahi /etc/resolv.conf
+    else
+        test -f /etc/resolv.conf.avahi || mv /etc/resolv.conf /etc/resolv.conf.avahi
+
+        for n in $AVAHI_DNS_SERVERS ; do 
+            echo "nameserver $n"
+        done > /etc/resolv.conf
+    fi
+fi
diff --git a/avahi-dnsconfd/main.c b/avahi-dnsconfd/main.c
new file mode 100644
index 0000000..918beeb
--- /dev/null
+++ b/avahi-dnsconfd/main.c
@@ -0,0 +1,608 @@
+/* $Id$ */
+
+/***
+  This file is part of avahi.
+ 
+  avahi is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+ 
+  avahi is distributed in the hope that it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
+  Public License for more details.
+ 
+  You should have received a copy of the GNU Lesser General Public
+  License along with avahi; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <sys/un.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <signal.h>
+#include <sys/wait.h>
+#include <getopt.h>
+
+#include <glib.h>
+
+#include <avahi-common/util.h>
+#include <avahi-core/llist.h>
+
+#include <libdaemon/dfork.h>
+#include <libdaemon/dsignal.h>
+#include <libdaemon/dlog.h>
+#include <libdaemon/dpid.h>
+#include <libdaemon/dexec.h>
+
+#define BROWSE_DNS_SERVERS "BROWSE-DNS-SERVERS\n"
+
+static enum {
+    ACKWAIT,
+    BROWSING
+} state = ACKWAIT;
+
+static gboolean quit = FALSE;
+
+static enum {
+    DAEMON_RUN,
+    DAEMON_KILL,
+    DAEMON_RELOAD,
+    DAEMON_VERSION,
+    DAEMON_HELP
+} command = DAEMON_RUN;
+
+static gboolean daemonize = FALSE;
+
+typedef struct DNSServerInfo DNSServerInfo;
+
+struct DNSServerInfo {
+    gint interface;
+    guchar protocol;
+    gchar *address;
+    AVAHI_LLIST_FIELDS(DNSServerInfo, servers);
+};
+
+static AVAHI_LLIST_HEAD(DNSServerInfo, servers);
+
+static void server_info_free(DNSServerInfo *i) {
+    g_assert(i);
+
+    g_free(i->address);
+    
+    AVAHI_LLIST_REMOVE(DNSServerInfo, servers, servers, i);
+    g_free(i);
+}
+
+static DNSServerInfo* get_server_info(gint interface, guchar protocol, const gchar *address) {
+    DNSServerInfo *i;
+    g_assert(address);
+
+    for (i = servers; i; i = i->servers_next)
+        if (i->interface == interface &&
+            i->protocol == protocol &&
+            strcmp(i->address, address) == 0)
+            return i;
+
+    return NULL;
+}
+
+static DNSServerInfo* new_server_info(gint interface, guchar protocol, const gchar *address) {
+    DNSServerInfo *i;
+    
+    g_assert(address);
+
+    i = g_new(DNSServerInfo, 1);
+    i->interface = interface;
+    i->protocol = protocol;
+    i->address = g_strdup(address);
+
+    AVAHI_LLIST_PREPEND(DNSServerInfo, servers, servers, i);
+    
+    return i;
+}
+
+static int open_socket(void) {
+    int fd = -1;
+    struct sockaddr_un sa;
+
+    if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
+        daemon_log(LOG_ERR, "socket(): %s", strerror(errno));
+        goto fail;
+    }
+
+    if (avahi_set_cloexec(fd) < 0) {
+        daemon_log(LOG_ERR, "fcntl(): %s", strerror(errno));
+        goto fail;
+    }
+    
+    memset(&sa, 0, sizeof(sa));
+    sa.sun_family = AF_UNIX;
+    strncpy(sa.sun_path, AVAHI_SOCKET, sizeof(sa.sun_path)-1);
+    sa.sun_path[sizeof(sa.sun_path)-1] = 0;
+
+    if (connect(fd, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
+        daemon_log(LOG_ERR, "connect(): %s", strerror(errno));
+        goto fail;
+    }
+
+    return fd;
+    
+fail:
+    if (fd >= 0)
+        close(fd);
+
+    return -1;
+}
+
+static ssize_t loop_write(int fd, const void*data, size_t size) {
+
+    ssize_t ret = 0;
+    g_assert(fd >= 0 && data && size);
+
+    while (size > 0) {
+        ssize_t r;
+
+        if ((r = write(fd, data, size)) < 0)
+            return r;
+
+        if (r == 0)
+            break;
+
+        ret += r;
+        data = (guint8*) data + r;
+        size -= r;
+    }
+
+    return ret;
+}
+
+static gchar *concat_dns_servers(gint interface) {
+    DNSServerInfo *i;
+    gchar *r = NULL;
+    
+    for (i = servers; i; i = i->servers_next)
+        if (i->interface == interface || interface <= 0) {
+            gchar *t;
+
+            if (!r)
+                t = g_strdup(i->address);
+            else
+                t = g_strdup_printf("%s %s", r, i->address);
+
+            g_free(r);
+            r = t;
+        }
+
+    return r;
+}
+
+static gchar *getifname(gint interface, gchar *name, guint len) {
+    int fd = -1;
+    gchar *ret = NULL;
+    struct ifreq ifr;
+
+    g_assert(interface >= 0);
+    
+    if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
+        daemon_log(LOG_ERR, "socket(): %s", strerror(errno));
+        goto finish;
+    }
+
+    memset(&ifr, 0, sizeof(ifr));
+    ifr.ifr_ifindex = interface;
+    
+    if (ioctl(fd, SIOCGIFNAME, &ifr) < 0) {
+        daemon_log(LOG_ERR, "SIOCGIFNAME: %s\n", strerror(errno));
+        goto finish;
+    }
+
+    strncpy(name, ifr.ifr_name, len-1);
+    name[len-1] = 0;
+    ret = name;
+    
+finish:
+    if (fd >= 0)
+        close(fd);
+    
+    return ret;
+ }
+
+static void run_script(gboolean new, gint interface, guchar protocol, const gchar *address) {
+    gchar *p;
+    g_assert(interface > 0);
+    gint ret;
+    gchar ia[16], pa[16];
+    gchar name[IFNAMSIZ+1];
+
+    if (!getifname(interface, name, sizeof(name))) 
+        return;
+    
+    p = concat_dns_servers(interface);
+    g_setenv("AVAHI_INTERFACE_DNS_SERVERS", p ? p : "", TRUE);
+    g_free(p); 
+
+    p = concat_dns_servers(-1);
+    g_setenv("AVAHI_DNS_SERVERS", p ? p : "", TRUE);
+    g_free(p); 
+
+    g_setenv("AVAHI_INTERFACE", name, TRUE);
+    
+    snprintf(ia, sizeof(ia), "%i", interface);
+    snprintf(pa, sizeof(pa), "%u", protocol);
+
+    if (daemon_exec("/", &ret, AVAHI_DNSCONF_SCRIPT, AVAHI_DNSCONF_SCRIPT, new ? "+" : "-", address, ia, pa, NULL) < 0)
+        daemon_log(LOG_WARNING, "Failed to run script");
+    else if (ret != 0)
+        daemon_log(LOG_WARNING, "Script returned with non-zero exit code %i", ret);
+}
+
+static gint new_line(const gchar *l) {
+    g_assert(l);
+
+    if (state == ACKWAIT) {
+        if (*l != '+') {
+            daemon_log(LOG_ERR, "Avahi command failed: %s", l);
+            return -1;
+        }
+
+        daemon_log(LOG_INFO, "Successfully connected to Avahi daemon.");
+        state = BROWSING;
+    } else {
+        gint interface;
+        guint protocol;
+        guint port;
+        gchar a[64];
+        
+        g_assert(state == BROWSING); 
+
+        if (*l != '<' && *l != '>') {
+            daemon_log(LOG_ERR, "Avahi sent us an invalid browsing line: %s", l);
+            return -1;
+        }
+
+        if (sscanf(l+1, "%i %u %64s %u", &interface, &protocol, a, &port) != 4) {
+            daemon_log(LOG_ERR, "Failed to parse browsing line: %s", l);
+            return -1;
+        }
+
+        if (*l == '>') {
+            if (port != 53)
+                daemon_log(LOG_WARNING, "DNS server with port address != 53 found, ignoring");
+            else {
+                daemon_log(LOG_INFO, "New DNS Server %s (interface: %i.%u)", a, interface, protocol);
+                new_server_info(interface, (guchar) protocol, a);
+                run_script(TRUE, interface, (guchar) protocol, a);
+            }
+        } else {
+            DNSServerInfo *i;
+
+            if (port == 53) 
+                if ((i = get_server_info(interface, (guchar) protocol, a))) {
+                    daemon_log(LOG_INFO, "DNS Server %s removed (interface: %i.%u)", a, interface, protocol);
+                    server_info_free(i);
+                    run_script(FALSE, interface, (guchar) protocol, a);
+                }
+        }
+
+    }
+    
+    return 0;
+}
+
+static gint do_connect(void) {
+    gint fd = -1;
+    
+    if ((fd = open_socket()) < 0)
+        goto fail;
+
+    if (loop_write(fd, BROWSE_DNS_SERVERS, sizeof(BROWSE_DNS_SERVERS)-1) < 0) {
+        daemon_log(LOG_ERR, "write(): %s", strerror(errno));
+        goto fail;
+    }
+
+    state = ACKWAIT;
+    return fd;
+
+fail:
+    if (fd >= 0)
+        close(fd);
+    
+    return -1;
+}
+
+static void free_dns_server_info_list(void) {
+    while (servers) {
+        gint interface = servers->interface;
+        guchar protocol = servers->protocol;
+        gchar *address = g_strdup(servers->address);
+        server_info_free(servers);
+        
+        run_script(FALSE, interface, protocol, address);
+        g_free(address);
+    }
+}
+
+static void help(FILE *f, const gchar *argv0) {
+    fprintf(f,
+            "%s [options]\n"
+            "    -h --help        Show this help\n"
+            "    -D --daemonize   Daemonize after startup\n"
+            "    -k --kill        Kill a running daemon\n"
+            "    -r --reload      Request a running daemon to reload static services\n"
+            "    -V --version     Show version\n",
+            argv0);
+}
+
+static gint parse_command_line(int argc, char *argv[]) {
+    gint c;
+    
+    static const struct option const long_options[] = {
+        { "help",      no_argument,       NULL, 'h' },
+        { "daemonize", no_argument,       NULL, 'D' },
+        { "kill",      no_argument,       NULL, 'k' },
+        { "version",   no_argument,       NULL, 'V' },
+        { "reload",    no_argument,       NULL, 'r' },
+    };
+
+    opterr = 0;
+    while ((c = getopt_long(argc, argv, "hDkVr", long_options, NULL)) >= 0) {
+
+        switch(c) {
+            case 'h':
+                command = DAEMON_HELP;
+                break;
+            case 'D':
+                daemonize = TRUE;
+                break;
+            case 'k':
+                command = DAEMON_KILL;
+                break;
+            case 'V':
+                command = DAEMON_VERSION;
+                break;
+            case 'r':
+                command = DAEMON_RELOAD;
+                break;
+            default:
+                fprintf(stderr, "Invalid command line argument: %c\n", c);
+                return -1;
+        }
+    }
+
+    if (optind < argc) {
+        fprintf(stderr, "Too many arguments\n");
+        return -1;
+    }
+        
+    return 0;
+}
+
+static int run_daemon(void) {
+    gint fd = -1, ret = -1;
+    gchar buf[1024];
+    size_t buflen = 0;
+
+    AVAHI_LLIST_HEAD_INIT(DNSServerInfo, servers);
+    
+    daemon_signal_init(SIGINT, SIGTERM, SIGCHLD, SIGHUP, 0);
+    
+    if ((fd = do_connect()) < 0)
+        goto finish;
+
+    if (daemonize)
+        daemon_retval_send(0);
+    
+    while (!quit) {
+        fd_set rfds, wfds;
+
+        FD_ZERO(&rfds);
+        FD_ZERO(&wfds);
+
+        FD_SET(fd, &rfds);
+        FD_SET(daemon_signal_fd(), &rfds);
+
+        for (;;) {
+            if (select(fd+1, &rfds, NULL, NULL, NULL) < 0) {
+                if (errno == EINTR)
+                    continue;
+
+                daemon_log(LOG_ERR, "select(): %s", strerror(errno));
+                goto finish;
+            }
+
+            break;
+        }
+
+        if (FD_ISSET(daemon_signal_fd(), &rfds)) {
+
+            int sig;
+
+            if ((sig = daemon_signal_next()) <= 0) {
+                daemon_log(LOG_ERR, "daemon_signal_next() failed");
+                goto finish;
+            }
+
+            switch(sig) {
+                case SIGINT:
+                case SIGTERM:
+                    daemon_log(LOG_INFO, "Got %s, quitting.", sig == SIGINT ? "SIGINT" : "SIGTERM");
+                    ret = 0;
+                    goto finish;
+
+                case SIGCHLD:
+                    waitpid(-1, NULL, WNOHANG);
+                    break;
+                    
+                case SIGHUP:
+                    daemon_log(LOG_INFO, "Rrefreshing DNS Server list");
+                    
+                    close(fd);
+                    free_dns_server_info_list();
+                    
+                    if ((fd = do_connect()) < 0)
+                        goto finish;
+                    
+                    break;
+            }
+            
+        } else if (FD_ISSET(fd, &rfds)) {
+            ssize_t r;
+            gchar *n;
+
+            if ((r = read(fd, buf, sizeof(buf) - buflen - 1)) <= 0) {
+                daemon_log(LOG_ERR, "read(): %s", r < 0 ? strerror(errno) : "EOF");
+                goto finish;
+            }
+
+            buflen += r;
+            g_assert(buflen <= sizeof(buf)-1);
+
+            while ((n = memchr(buf, '\n', buflen))) {
+                *(n++) = 0;
+
+                if (new_line(buf) < 0)
+                    goto finish;
+
+                buflen -= (n - buf);
+                memmove(buf, n, buflen);
+            }
+
+            if (buflen >= sizeof(buf)-1) {
+                /* The incoming line is horribly long */
+                buf[sizeof(buf)-1] = 0;
+                
+                if (new_line(buf) < 0)
+                    goto finish;
+                
+                buflen = 0;
+            }
+        }
+    }
+
+    ret = 0;
+    
+finish:
+
+    free_dns_server_info_list();
+
+    if (fd >= 0)
+        close(fd);
+    
+    daemon_signal_done();
+
+    return ret;
+}
+
+static const char* pid_file_proc(void) {
+    return AVAHI_RUNTIME_DIR"/avahi-dnsconfd.pid";
+}
+
+gint main(gint argc, gchar *argv[]) {
+    gchar *argv0;
+    gint r = 1;
+    gboolean wrote_pid_file = FALSE;
+
+    if ((argv0 = strrchr(argv[0], '/')))
+        argv0++;
+    else
+        argv0 = argv[0];
+
+    daemon_pid_file_ident = daemon_log_ident = argv0;
+    daemon_pid_file_proc = pid_file_proc;
+    
+    if (parse_command_line(argc, argv) < 0)
+        goto finish;
+
+    if (command == DAEMON_RUN) {
+        pid_t pid;
+
+        if (getuid() != 0) {
+            daemon_log(LOG_ERR, "This program is intended to be run as root.");
+            goto finish;
+        }
+
+        if ((pid = daemon_pid_file_is_running()) >= 0) {
+            daemon_log(LOG_ERR, "Daemon already running on PID %u", pid);
+            goto finish;
+        }
+
+        if (daemonize) {
+            daemon_retval_init();
+            
+            if ((pid = daemon_fork()) < 0)
+                goto finish;
+            else if (pid != 0) {
+                int ret;
+                /** Parent **/
+
+                if ((ret = daemon_retval_wait(20)) < 0) {
+                    daemon_log(LOG_ERR, "Could not recieve return value from daemon process.");
+                    goto finish;
+                }
+
+                r = ret;
+                goto finish;
+            }
+
+            /* Child */
+        }
+
+        chdir("/");
+
+        if (daemon_pid_file_create() < 0) {
+            daemon_log(LOG_ERR, "Failed to create PID file: %s", strerror(errno));
+
+            if (daemonize)
+                daemon_retval_send(1);
+            goto finish;
+        } else
+            wrote_pid_file = TRUE;
+
+        if (run_daemon() < 0)
+            goto finish;
+
+    } else if (command == DAEMON_HELP) {
+        help(stdout, argv0);
+        
+    } else if (command == DAEMON_VERSION) {
+        printf("%s "PACKAGE_VERSION"\n", argv0);
+        
+    } else if (command == DAEMON_KILL) {
+        if (daemon_pid_file_kill_wait(SIGTERM, 5) < 0) {
+            daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno));
+            goto finish;
+        }
+        
+    } else if (command == DAEMON_RELOAD) {
+        if (daemon_pid_file_kill(SIGHUP) < 0) {
+            daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno));
+            goto finish;
+        }
+    }
+
+    r = 0;
+    
+finish:
+
+    if (daemonize)
+        daemon_retval_done();
+    
+    if (wrote_pid_file)
+        daemon_pid_file_remove();
+
+    return r;
+}