socket: support netlink sockets

This commit is contained in:
Lennart Poettering 2011-04-10 03:27:00 +02:00
parent b9a2a36b51
commit 7a22745ac3
5 changed files with 267 additions and 92 deletions

View File

@ -218,6 +218,22 @@
directive above.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>ListenNetlink=</varname></term>
<listitem><para>Specifies a Netlink
family to create a socket for to
listen on. This expects a short string
referring to the AF_NETLINK family
name (such as <varname>audit</varname>
or <varname>kobject-uevent</varname>)
as argument, optionally suffixed by a
whitespace followed by a multicast
group integer. Behaviour otherwise is
very similar to the
<varname>ListenDatagram=</varname>
directive above.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>BindIPv6Only=</varname></term>
<listitem><para>Takes a one of

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@ -220,6 +220,15 @@ static int config_parse_listen(
}
path_kill_slashes(p->path);
} else if (streq(lvalue, "ListenNetlink")) {
p->type = SOCKET_SOCKET;
if (socket_address_parse_netlink(&p->address, rvalue) < 0) {
log_error("[%s:%u] Failed to parse address value, ignoring: %s", filename, line, rvalue);
free(p);
return 0;
}
} else {
p->type = SOCKET_SOCKET;
@ -1892,6 +1901,7 @@ static int load_from_path(Unit *u, const char *path) {
{ "ListenDatagram", config_parse_listen, 0, &u->socket, "Socket" },
{ "ListenSequentialPacket", config_parse_listen, 0, &u->socket, "Socket" },
{ "ListenFIFO", config_parse_listen, 0, &u->socket, "Socket" },
{ "ListenNetlink", config_parse_listen, 0, &u->socket, "Socket" },
{ "BindIPv6Only", config_parse_socket_bind, 0, &u->socket, "Socket" },
{ "Backlog", config_parse_unsigned, 0, &u->socket.backlog, "Socket" },
{ "BindToDevice", config_parse_bindtodevice, 0, &u->socket, "Socket" },

View File

@ -189,50 +189,102 @@ int socket_address_parse(SocketAddress *a, const char *s) {
return 0;
}
int socket_address_parse_netlink(SocketAddress *a, const char *s) {
int family;
unsigned group = 0;
char* sfamily = NULL;
assert(a);
assert(s);
zero(*a);
a->type = SOCK_RAW;
errno = 0;
if (sscanf(s, "%ms %u", &sfamily, &group) < 1)
return errno ? -errno : -EINVAL;
if ((family = netlink_family_from_string(sfamily)) < 0)
if (safe_atoi(sfamily, &family) < 0) {
free(sfamily);
return -EINVAL;
}
free(sfamily);
a->sockaddr.nl.nl_family = AF_NETLINK;
a->sockaddr.nl.nl_groups = group;
a->type = SOCK_RAW;
a->size = sizeof(struct sockaddr_nl);
a->protocol = family;
return 0;
}
int socket_address_verify(const SocketAddress *a) {
assert(a);
switch (socket_address_family(a)) {
case AF_INET:
if (a->size != sizeof(struct sockaddr_in))
return -EINVAL;
if (a->sockaddr.in4.sin_port == 0)
return -EINVAL;
case AF_INET:
if (a->size != sizeof(struct sockaddr_in))
return -EINVAL;
return 0;
if (a->sockaddr.in4.sin_port == 0)
return -EINVAL;
case AF_INET6:
if (a->size != sizeof(struct sockaddr_in6))
return -EINVAL;
if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
return -EINVAL;
if (a->sockaddr.in6.sin6_port == 0)
return -EINVAL;
return 0;
return 0;
case AF_INET6:
if (a->size != sizeof(struct sockaddr_in6))
return -EINVAL;
case AF_UNIX:
if (a->size < offsetof(struct sockaddr_un, sun_path))
return -EINVAL;
if (a->sockaddr.in6.sin6_port == 0)
return -EINVAL;
if (a->size > offsetof(struct sockaddr_un, sun_path)) {
if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
return -EINVAL;
if (a->sockaddr.un.sun_path[0] != 0) {
char *e;
return 0;
/* path */
if (!(e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path))))
return -EINVAL;
case AF_UNIX:
if (a->size < offsetof(struct sockaddr_un, sun_path))
return -EINVAL;
if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1)
return -EINVAL;
}
if (a->size > offsetof(struct sockaddr_un, sun_path)) {
if (a->sockaddr.un.sun_path[0] != 0) {
char *e;
/* path */
if (!(e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path))))
return -EINVAL;
if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1)
return -EINVAL;
}
}
return 0;
if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM && a->type == SOCK_SEQPACKET)
return -EINVAL;
default:
return -EAFNOSUPPORT;
return 0;
case AF_NETLINK:
if (a->size != sizeof(struct sockaddr_nl))
return -EINVAL;
if (a->type != SOCK_RAW && a->type != SOCK_DGRAM)
return -EINVAL;
return 0;
default:
return -EAFNOSUPPORT;
}
}
@ -245,74 +297,89 @@ int socket_address_print(const SocketAddress *a, char **p) {
return r;
switch (socket_address_family(a)) {
case AF_INET: {
char *ret;
if (!(ret = new(char, INET_ADDRSTRLEN+1+5+1)))
case AF_INET: {
char *ret;
if (!(ret = new(char, INET_ADDRSTRLEN+1+5+1)))
return -ENOMEM;
if (!inet_ntop(AF_INET, &a->sockaddr.in4.sin_addr, ret, INET_ADDRSTRLEN)) {
free(ret);
return -errno;
}
sprintf(strchr(ret, 0), ":%u", ntohs(a->sockaddr.in4.sin_port));
*p = ret;
return 0;
}
case AF_INET6: {
char *ret;
if (!(ret = new(char, 1+INET6_ADDRSTRLEN+2+5+1)))
return -ENOMEM;
ret[0] = '[';
if (!inet_ntop(AF_INET6, &a->sockaddr.in6.sin6_addr, ret+1, INET6_ADDRSTRLEN)) {
free(ret);
return -errno;
}
sprintf(strchr(ret, 0), "]:%u", ntohs(a->sockaddr.in6.sin6_port));
*p = ret;
return 0;
}
case AF_UNIX: {
char *ret;
if (a->size <= offsetof(struct sockaddr_un, sun_path)) {
if (!(ret = strdup("<unnamed>")))
return -ENOMEM;
if (!inet_ntop(AF_INET, &a->sockaddr.in4.sin_addr, ret, INET_ADDRSTRLEN)) {
free(ret);
return -errno;
}
} else if (a->sockaddr.un.sun_path[0] == 0) {
/* abstract */
sprintf(strchr(ret, 0), ":%u", ntohs(a->sockaddr.in4.sin_port));
*p = ret;
return 0;
}
/* FIXME: We assume we can print the
* socket path here and that it hasn't
* more than one NUL byte. That is
* actually an invalid assumption */
case AF_INET6: {
char *ret;
if (!(ret = new(char, 1+INET6_ADDRSTRLEN+2+5+1)))
if (!(ret = new(char, sizeof(a->sockaddr.un.sun_path)+1)))
return -ENOMEM;
ret[0] = '[';
if (!inet_ntop(AF_INET6, &a->sockaddr.in6.sin6_addr, ret+1, INET6_ADDRSTRLEN)) {
free(ret);
return -errno;
}
ret[0] = '@';
memcpy(ret+1, a->sockaddr.un.sun_path+1, sizeof(a->sockaddr.un.sun_path)-1);
ret[sizeof(a->sockaddr.un.sun_path)] = 0;
sprintf(strchr(ret, 0), "]:%u", ntohs(a->sockaddr.in6.sin6_port));
*p = ret;
return 0;
} else {
if (!(ret = strdup(a->sockaddr.un.sun_path)))
return -ENOMEM;
}
case AF_UNIX: {
char *ret;
*p = ret;
return 0;
}
if (a->size <= offsetof(struct sockaddr_un, sun_path)) {
case AF_NETLINK: {
const char *sfamily;
if (!(ret = strdup("<unamed>")))
return -ENOMEM;
if ((sfamily = netlink_family_to_string(a->protocol)))
r = asprintf(p, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
else
r = asprintf(p, "%i %u", a->protocol, a->sockaddr.nl.nl_groups);
} else if (a->sockaddr.un.sun_path[0] == 0) {
/* abstract */
if (r < 0)
return -ENOMEM;
/* FIXME: We assume we can print the
* socket path here and that it hasn't
* more than one NUL byte. That is
* actually an invalid assumption */
return 0;
}
if (!(ret = new(char, sizeof(a->sockaddr.un.sun_path)+1)))
return -ENOMEM;
ret[0] = '@';
memcpy(ret+1, a->sockaddr.un.sun_path+1, sizeof(a->sockaddr.un.sun_path)-1);
ret[sizeof(a->sockaddr.un.sun_path)] = 0;
} else {
if (!(ret = strdup(a->sockaddr.un.sun_path)))
return -ENOMEM;
}
*p = ret;
return 0;
}
default:
return -EINVAL;
default:
return -EINVAL;
}
}
@ -341,7 +408,7 @@ int socket_address_listen(
if (r < 0)
return r;
fd = socket(socket_address_family(a), a->type | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
fd = socket(socket_address_family(a), a->type | SOCK_NONBLOCK | SOCK_CLOEXEC, a->protocol);
r = fd < 0 ? -errno : 0;
label_socket_clear();
@ -356,14 +423,16 @@ int socket_address_listen(
goto fail;
}
if (bind_to_device)
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, bind_to_device, strlen(bind_to_device)+1) < 0)
goto fail;
if (socket_address_family(a) == AF_INET || socket_address_family(a) == AF_INET6) {
if (bind_to_device)
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, bind_to_device, strlen(bind_to_device)+1) < 0)
goto fail;
if (free_bind) {
one = 1;
if (setsockopt(fd, IPPROTO_IP, IP_FREEBIND, &one, sizeof(one)) < 0)
log_warning("IP_FREEBIND failed: %m");
if (free_bind) {
one = 1;
if (setsockopt(fd, IPPROTO_IP, IP_FREEBIND, &one, sizeof(one)) < 0)
log_warning("IP_FREEBIND failed: %m");
}
}
one = 1;
@ -397,7 +466,7 @@ int socket_address_listen(
if (r < 0)
goto fail;
if (a->type == SOCK_STREAM)
if (socket_address_can_accept(a))
if (listen(fd, backlog) < 0)
goto fail;
@ -471,6 +540,16 @@ bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
break;
case AF_NETLINK:
if (a->protocol != b->protocol)
return false;
if (a->sockaddr.nl.nl_groups != b->sockaddr.nl.nl_groups)
return false;
break;
default:
/* Cannot compare, so we assume the addresses are different */
return false;
@ -493,6 +572,18 @@ bool socket_address_is(const SocketAddress *a, const char *s, int type) {
return socket_address_equal(a, &b);
}
bool socket_address_is_netlink(const SocketAddress *a, const char *s) {
struct SocketAddress b;
assert(a);
assert(s);
if (socket_address_parse_netlink(&b, s) < 0)
return false;
return socket_address_equal(a, &b);
}
bool socket_address_needs_mount(const SocketAddress *a, const char *prefix) {
assert(a);
@ -523,6 +614,28 @@ bool socket_ipv6_is_supported(void) {
return enabled;
}
static const char* const netlink_family_table[] = {
[NETLINK_ROUTE] = "route",
[NETLINK_FIREWALL] = "firewall",
[NETLINK_INET_DIAG] = "inet-diag",
[NETLINK_NFLOG] = "nflog",
[NETLINK_XFRM] = "xfrm",
[NETLINK_SELINUX] = "selinux",
[NETLINK_ISCSI] = "iscsi",
[NETLINK_AUDIT] = "audit",
[NETLINK_FIB_LOOKUP] = "fib-lookup",
[NETLINK_CONNECTOR] = "connector",
[NETLINK_NETFILTER] = "netfilter",
[NETLINK_IP6_FW] = "ip6-fw",
[NETLINK_DNRTMSG] = "dnrtmsg",
[NETLINK_KOBJECT_UEVENT] = "kobject-uevent",
[NETLINK_GENERIC] = "generic",
[NETLINK_SCSITRANSPORT] = "scsitransport",
[NETLINK_ECRYPTFS] = "ecryptfs"
};
DEFINE_STRING_TABLE_LOOKUP(netlink_family, int);
static const char* const socket_address_bind_ipv6_only_table[_SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX] = {
[SOCKET_ADDRESS_DEFAULT] = "default",
[SOCKET_ADDRESS_BOTH] = "both",

View File

@ -26,6 +26,8 @@
#include <netinet/in.h>
#include <sys/un.h>
#include <net/if.h>
#include <asm/types.h>
#include <linux/netlink.h>
#include "macro.h"
#include "util.h"
@ -35,6 +37,7 @@ union sockaddr_union {
struct sockaddr_in in4;
struct sockaddr_in6 in6;
struct sockaddr_un un;
struct sockaddr_nl nl;
struct sockaddr_storage storage;
};
@ -47,6 +50,9 @@ typedef struct SocketAddress {
/* Socket type, i.e. SOCK_STREAM, SOCK_DGRAM, ... */
int type;
/* Socket protocol, IPPROTO_xxx, usually 0, except for netlink */
int protocol;
} SocketAddress;
typedef enum SocketAddressBindIPv6Only {
@ -60,6 +66,7 @@ typedef enum SocketAddressBindIPv6Only {
#define socket_address_family(a) ((a)->sockaddr.sa.sa_family)
int socket_address_parse(SocketAddress *a, const char *s);
int socket_address_parse_netlink(SocketAddress *a, const char *s);
int socket_address_print(const SocketAddress *a, char **p);
int socket_address_verify(const SocketAddress *a);
@ -77,6 +84,7 @@ int socket_address_listen(
int *ret);
bool socket_address_is(const SocketAddress *a, const char *s, int type);
bool socket_address_is_netlink(const SocketAddress *a, const char *s);
bool socket_address_equal(const SocketAddress *a, const SocketAddress *b);
@ -85,6 +93,9 @@ bool socket_address_needs_mount(const SocketAddress *a, const char *prefix);
const char* socket_address_bind_ipv6_only_to_string(SocketAddressBindIPv6Only b);
SocketAddressBindIPv6Only socket_address_bind_ipv6_only_from_string(const char *s);
const char* netlink_family_to_string(int b);
int netlink_family_from_string(const char *s);
bool socket_ipv6_is_supported(void);
#endif

View File

@ -366,7 +366,10 @@ static int socket_load(Unit *u) {
return socket_verify(s);
}
static const char* listen_lookup(int type) {
static const char* listen_lookup(int family, int type) {
if (family == AF_NETLINK)
return "ListenNetlink";
if (type == SOCK_STREAM)
return "ListenStream";
@ -477,7 +480,7 @@ static void socket_dump(Unit *u, FILE *f, const char *prefix) {
else
t = k;
fprintf(f, "%s%s: %s\n", prefix, listen_lookup(p->address.type), t);
fprintf(f, "%s%s: %s\n", prefix, listen_lookup(socket_address_family(&p->address), p->address.type), t);
free(k);
} else
fprintf(f, "%sListenFIFO: %s\n", prefix, p->path);
@ -1447,7 +1450,10 @@ static int socket_serialize(Unit *u, FILE *f, FDSet *fds) {
if ((r = socket_address_print(&p->address, &t)) < 0)
return r;
unit_serialize_item_format(u, f, "socket", "%i %i %s", copy, p->address.type, t);
if (socket_address_family(&p->address) == AF_NETLINK)
unit_serialize_item_format(u, f, "netlink", "%i %s", copy, t);
else
unit_serialize_item_format(u, f, "socket", "%i %i %s", copy, p->address.type, t);
free(t);
} else {
assert(p->type == SOCKET_FIFO);
@ -1542,6 +1548,25 @@ static int socket_deserialize_item(Unit *u, const char *key, const char *value,
}
}
} else if (streq(key, "netlink")) {
int fd, skip = 0;
SocketPort *p;
if (sscanf(value, "%i %n", &fd, &skip) < 1 || fd < 0 || !fdset_contains(fds, fd))
log_debug("Failed to parse socket value %s", value);
else {
LIST_FOREACH(port, p, s->ports)
if (socket_address_is_netlink(&p->address, value+skip))
break;
if (p) {
if (p->fd >= 0)
close_nointr_nofail(p->fd);
p->fd = fdset_remove(fds, fd);
}
}
} else
log_debug("Unknown serialization key '%s'", key);