Implement SocketUser= and SocketGroup= for [Socket]

Since we already allow defining the mode of AF_UNIX sockets and FIFO, it
makes sense to also allow specific user/group ownership of the socket
file for restricting access.

diff --git a/man/systemd.socket.xml b/man/systemd.socket.xml
index 4b1fcc8b0cf725d5b85f7472e17e7d4bfb7328b7..dc0d78f0a208527dee9acdd697d8f74a9c91d3e4 100644 (file)
--- a/man/systemd.socket.xml
+++ b/man/systemd.socket.xml
@@ -357,6 +357,30 @@
                                 0666.</para></listitem>
                         </varlistentry>
 
                                 0666.</para></listitem>
                         </varlistentry>
 

+                        <varlistentry>
+                                <term><varname>SocketUser=</varname></term>
+                                <listitem><para>If listening on a file system
+                                socket or FIFO, this option specifies the
+                                user owner of the created socket. When
+                                defining this, keep in mind that name
+                                switch services for user name lookups may
+                                not be available. It is advisable to use a
+                                numeric UID for this
+                                setting.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><varname>SocketGroup=</varname></term>
+                                <listitem><para>If listening on a file system
+                                socket or FIFO, this option specifies the
+                                group owner of the created socket. When
+                                defining this, keep in mind that name
+                                switch services for group name lookups may
+                                not be available. It is advisable to use a
+                                numeric GID for this
+                                setting.</para></listitem>
+                        </varlistentry>
+

                         <varlistentry>
                                 <term><varname>Accept=</varname></term>
                                 <listitem><para>Takes a boolean
                         <varlistentry>
                                 <term><varname>Accept=</varname></term>
                                 <listitem><para>Takes a boolean

diff --git a/src/core/dbus-socket.c b/src/core/dbus-socket.c
index 095a0316120c16a7d6fe8546dac5919ecee195bc..887c80eb893605a54a47f1960a8771174da1cbe5 100644 (file)
--- a/src/core/dbus-socket.c
+++ b/src/core/dbus-socket.c
@@ -43,6 +43,8 @@
         "  <property name=\"BindToDevice\" type=\"s\" access=\"read\"/>\n" \
         "  <property name=\"DirectoryMode\" type=\"u\" access=\"read\"/>\n" \
         "  <property name=\"SocketMode\" type=\"u\" access=\"read\"/>\n" \
         "  <property name=\"BindToDevice\" type=\"s\" access=\"read\"/>\n" \
         "  <property name=\"DirectoryMode\" type=\"u\" access=\"read\"/>\n" \
         "  <property name=\"SocketMode\" type=\"u\" access=\"read\"/>\n" \

+        "  <property name=\"SocketUser\" type=\"s\" access=\"read\"/>\n" \
+        "  <property name=\"SocketGroup\" type=\"s\" access=\"read\"/>\n" \

         "  <property name=\"Accept\" type=\"b\" access=\"read\"/>\n"    \
         "  <property name=\"KeepAlive\" type=\"b\" access=\"read\"/>\n" \
         "  <property name=\"Priority\" type=\"i\" access=\"read\"/>\n"  \
         "  <property name=\"Accept\" type=\"b\" access=\"read\"/>\n"    \
         "  <property name=\"KeepAlive\" type=\"b\" access=\"read\"/>\n" \
         "  <property name=\"Priority\" type=\"i\" access=\"read\"/>\n"  \


@@ -109,6 +111,8 @@ static const BusProperty bus_socket_properties[] = {
         { "BindToDevice",   bus_property_append_string,        "s", offsetof(Socket, bind_to_device), true },
         { "DirectoryMode",  bus_property_append_mode,          "u", offsetof(Socket, directory_mode)  },
         { "SocketMode",     bus_property_append_mode,          "u", offsetof(Socket, socket_mode)     },
         { "BindToDevice",   bus_property_append_string,        "s", offsetof(Socket, bind_to_device), true },
         { "DirectoryMode",  bus_property_append_mode,          "u", offsetof(Socket, directory_mode)  },
         { "SocketMode",     bus_property_append_mode,          "u", offsetof(Socket, socket_mode)     },

+        { "SocketUser",     bus_property_append_string,        "s", offsetof(Socket, socket_user),    true },
+        { "SocketGroup",    bus_property_append_string,        "s", offsetof(Socket, socket_group),   true },

         { "Accept",         bus_property_append_bool,          "b", offsetof(Socket, accept)          },
         { "KeepAlive",      bus_property_append_bool,          "b", offsetof(Socket, keep_alive)      },
         { "Priority",       bus_property_append_int,           "i", offsetof(Socket, priority)        },
         { "Accept",         bus_property_append_bool,          "b", offsetof(Socket, accept)          },
         { "KeepAlive",      bus_property_append_bool,          "b", offsetof(Socket, keep_alive)      },
         { "Priority",       bus_property_append_int,           "i", offsetof(Socket, priority)        },

diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4
index 0c5ccebd736f4bc78e0db1b13845f45f4b398453..b48e9e9f56ec60892bd915ec2eba3849f0526d9a 100644 (file)
--- a/src/core/load-fragment-gperf.gperf.m4
+++ b/src/core/load-fragment-gperf.gperf.m4
@@ -189,6 +189,8 @@ Socket.ExecStopPost,             config_parse_exec,                  SOCKET_EXEC
 Socket.TimeoutSec,               config_parse_usec,                  0,                             offsetof(Socket, timeout_usec)
 Socket.DirectoryMode,            config_parse_mode,                  0,                             offsetof(Socket, directory_mode)
 Socket.SocketMode,               config_parse_mode,                  0,                             offsetof(Socket, socket_mode)
 Socket.TimeoutSec,               config_parse_usec,                  0,                             offsetof(Socket, timeout_usec)
 Socket.DirectoryMode,            config_parse_mode,                  0,                             offsetof(Socket, directory_mode)
 Socket.SocketMode,               config_parse_mode,                  0,                             offsetof(Socket, socket_mode)

+Socket.SocketUser,               config_parse_string,                0,                             offsetof(Socket, socket_user)
+Socket.SocketGroup,              config_parse_string,                0,                             offsetof(Socket, socket_group)

 Socket.Accept,                   config_parse_bool,                  0,                             offsetof(Socket, accept)
 Socket.MaxConnections,           config_parse_unsigned,              0,                             offsetof(Socket, max_connections)
 Socket.KeepAlive,                config_parse_bool,                  0,                             offsetof(Socket, keep_alive)
 Socket.Accept,                   config_parse_bool,                  0,                             offsetof(Socket, accept)
 Socket.MaxConnections,           config_parse_unsigned,              0,                             offsetof(Socket, max_connections)
 Socket.KeepAlive,                config_parse_bool,                  0,                             offsetof(Socket, keep_alive)

diff --git a/src/core/socket.c b/src/core/socket.c
index c0959815c174c89d34cd56082286a4a4507a403d..f3f09cac4326133e8af4c9ecb3a8a4132fd3a0e7 100644 (file)
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -136,6 +136,12 @@ static void socket_done(Unit *u) {
         free(s->smack_ip_in);
         free(s->smack_ip_out);
 
         free(s->smack_ip_in);
         free(s->smack_ip_out);
 

+        free(s->socket_user);
+        s->socket_user = NULL;
+
+        free(s->socket_group);
+        s->socket_group = NULL;
+

         unit_unwatch_timer(u, &s->timer_watch);
 }
 
         unit_unwatch_timer(u, &s->timer_watch);
 }
 


@@ -449,6 +455,16 @@ static void socket_dump(Unit *u, FILE *f, const char *prefix) {
                 prefix, yes_no(s->pass_sec),
                 prefix, strna(s->tcp_congestion));
 
                 prefix, yes_no(s->pass_sec),
                 prefix, strna(s->tcp_congestion));
 

+        if (s->socket_user)
+                fprintf(f,
+                        "SocketUser: %s\n",
+                        s->socket_user);
+
+        if (s->socket_group)
+                fprintf(f,
+                        "SocketGroup: %s\n",
+                        s->socket_group);
+

         if (s->control_pid > 0)
                 fprintf(f,
                         "%sControl PID: %lu\n",
         if (s->control_pid > 0)
                 fprintf(f,
                         "%sControl PID: %lu\n",


@@ -692,6 +708,9 @@ static void socket_close_fds(Socket *s) {
 }
 
 static void socket_apply_socket_options(Socket *s, int fd) {
 }
 
 static void socket_apply_socket_options(Socket *s, int fd) {

+        uid_t uid = 0;
+        gid_t gid = 0;
+

         assert(s);
         assert(fd >= 0);
 
         assert(s);
         assert(fd >= 0);
 


@@ -775,6 +794,21 @@ static void socket_apply_socket_options(Socket *s, int fd) {
         if (s->smack_ip_out)
                 if (fsetxattr(fd, "security.SMACK64IPOUT", s->smack_ip_out, strlen(s->smack_ip_out), 0) < 0)
                         log_error("fsetxattr(\"security.SMACK64IPOUT\"): %m");
         if (s->smack_ip_out)
                 if (fsetxattr(fd, "security.SMACK64IPOUT", s->smack_ip_out, strlen(s->smack_ip_out), 0) < 0)
                         log_error("fsetxattr(\"security.SMACK64IPOUT\"): %m");

+
+        if (s->socket_user &&
+            get_user_creds((const char **)&s->socket_user, &uid,
+                                NULL, NULL, NULL) < 0) {
+                log_warning("failed to lookup user: %s", s->socket_user);
+        }
+
+        if (s->socket_group &&
+            get_group_creds((const char **)&s->socket_group, &gid) < 0) {
+                log_warning("failed to lookup group: %s", s->socket_group);
+        }
+
+        if ((uid != 0 || gid != 0) && fchown(fd, uid, gid) < 0) {
+                log_warning("failed to change ownership of socket");
+        }

 }
 
 static void socket_apply_fifo_options(Socket *s, int fd) {
 }
 
 static void socket_apply_fifo_options(Socket *s, int fd) {


@@ -794,11 +828,15 @@ static int fifo_address_create(
                 const char *path,
                 mode_t directory_mode,
                 mode_t socket_mode,
                 const char *path,
                 mode_t directory_mode,
                 mode_t socket_mode,

+                const char *socket_user,
+                const char *socket_group,

                 int *_fd) {
 
         int fd = -1, r = 0;
         struct stat st;
         mode_t old_mask;
                 int *_fd) {
 
         int fd = -1, r = 0;
         struct stat st;
         mode_t old_mask;

+        uid_t uid = 0;
+        gid_t gid = 0;

 
         assert(path);
         assert(_fd);
 
         assert(path);
         assert(_fd);


@@ -823,7 +861,8 @@ static int fifo_address_create(
                 goto fail;
         }
 
                 goto fail;
         }
 

-        if ((fd = open(path, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK|O_NOFOLLOW)) < 0) {
+        fd = open(path, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK|O_NOFOLLOW);
+        if (fd < 0) {

                 r = -errno;
                 goto fail;
         }
                 r = -errno;
                 goto fail;
         }


@@ -835,15 +874,35 @@ static int fifo_address_create(
                 goto fail;
         }
 
                 goto fail;
         }
 

+        if (socket_user &&
+            get_user_creds(&socket_user, &uid, NULL, NULL, NULL) < 0) {
+                r = -errno;
+                log_error("failed to lookup user: %s", socket_user);
+                goto fail;
+        }
+
+        if (socket_group &&
+            get_group_creds(&socket_group, &gid) < 0) {
+                r = -errno;
+                log_error("failed to lookup group: %s", socket_group);
+                goto fail;
+        }
+

         if (!S_ISFIFO(st.st_mode) ||
             (st.st_mode & 0777) != (socket_mode & ~old_mask) ||
         if (!S_ISFIFO(st.st_mode) ||
             (st.st_mode & 0777) != (socket_mode & ~old_mask) ||

-            st.st_uid != getuid() ||
-            st.st_gid != getgid()) {
+            st.st_uid != uid ||
+            st.st_gid != gid) {

 
                 r = -EEXIST;
                 goto fail;
         }
 
 
                 r = -EEXIST;
                 goto fail;
         }
 

+        if ((uid != 0 || gid != 0) && fchown(fd, uid, gid) < 0) {
+                r = -errno;
+                log_error("failed to changed ownership of FIFO: %s", path);
+                goto fail;
+        }
+

         *_fd = fd;
         return 0;
 
         *_fd = fd;
         return 0;
 


@@ -1013,6 +1072,8 @@ static int socket_open_fds(Socket *s) {
                                              p->path,
                                              s->directory_mode,
                                              s->socket_mode,
                                              p->path,
                                              s->directory_mode,
                                              s->socket_mode,

+                                             s->socket_user,
+                                             s->socket_group,

                                              &p->fd)) < 0)
                                 goto rollback;
 
                                              &p->fd)) < 0)
                                 goto rollback;
 

diff --git a/src/core/socket.h b/src/core/socket.h
index f099520dcef1015164dc9b4067c4d40752a0f4a7..a273ac274097bc89e0f6c150088ae84ceb6b15e5 100644 (file)
--- a/src/core/socket.h
+++ b/src/core/socket.h
@@ -118,6 +118,8 @@ struct Socket {
 
         mode_t directory_mode;
         mode_t socket_mode;
 
         mode_t directory_mode;
         mode_t socket_mode;

+        char *socket_user;
+        char *socket_group;

 
         SocketResult result;
 
 
         SocketResult result;
 

diff --git a/src/shared/socket-label.c b/src/shared/socket-label.c
index ff212de825441d8fa45f069e9ce9e9aa518cb51f..d105a66fe84ece59cd5319c4b3f239f6bcabbf56 100644 (file)
--- a/src/shared/socket-label.c
+++ b/src/shared/socket-label.c
@@ -52,6 +52,7 @@ int socket_address_listen(
                 int *ret) {
 
         int r, fd, one;
                 int *ret) {
 
         int r, fd, one;

+

         assert(a);
         assert(ret);
 
         assert(a);
         assert(ret);