[MINOR] make it possible to set unix socket permissions

Under most systems, it is possible to set permissions on unix
sockets. This has been added to the listeners and to unix
sockets.

diff --git a/include/types/protocols.h b/include/types/protocols.h
index 2c68e8866f2c6f340dff9d61061d188aad027761..6ff44765169cb3cc1510348e658fabbd4b851ea0 100644 (file)
--- a/include/types/protocols.h
+++ b/include/types/protocols.h
@@ -24,6 +24,8 @@
 
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/un.h>
 
 #include <common/config.h>
 #include <common/mini-clist.h>
@@ -60,6 +62,13 @@ struct listener {
        void (*handler)(struct task *t, struct timeval *next); /* protocol handler */
        struct timeval *timeout;        /* pointer to client-side timeout */
        void *private;                  /* any private data which may be used by accept() */
+       union {                         /* protocol-dependant access restrictions */
+               struct {                /* UNIX socket permissions */
+                       uid_t uid;      /* -1 to leave unchanged */
+                       gid_t gid;      /* -1 to leave unchanged */
+                       mode_t mode;    /* 0 to leave unchanged */
+               } ux;
+       } perm;
 };
 
 /* This structure contains all information needed to easily handle a protocol.

diff --git a/src/proto_uxst.c b/src/proto_uxst.c
index 1920376697127fe68f349f03846748c7187453cc..e23d1d4f107095fbd684861440928d3298597888 100644 (file)
--- a/src/proto_uxst.c
+++ b/src/proto_uxst.c
@@ -59,10 +59,13 @@
 #endif
 
 /* This function creates a named PF_UNIX stream socket at address <path>. Note
- * that the path cannot be NULL nor empty.
+ * that the path cannot be NULL nor empty. <uid> and <gid> different of -1 will
+ * be used to change the socket owner. If <mode> is not 0, it will be used to
+ * restrict access to the socket. While it is known not to be portable on every
+ * OS, it's still useful where it works.
  * It returns the assigned file descriptor, or -1 in the event of an error.
  */
-static int create_uxst_socket(const char *path)
+static int create_uxst_socket(const char *path, uid_t uid, gid_t gid, mode_t mode)
 {
        char tempname[MAXPATHLEN];
        char backname[MAXPATHLEN];
@@ -132,6 +135,12 @@ static int create_uxst_socket(const char *path)
                goto err_unlink_temp;
        }
 
+       if (((uid != -1 || gid != -1) && (chown(tempname, uid, gid) == -1)) ||
+           (mode != 0 && chmod(tempname, mode) == -1)) {
+               Alert("cannot change UNIX socket ownership. Aborting.\n");
+               goto err_unlink_temp;
+       }
+
        if (listen(sock, 0) < 0) {
                Alert("cannot listen to socket for UNIX listener. Aborting.\n");
                goto err_unlink_temp;
@@ -217,7 +226,10 @@ static int uxst_bind_listeners(struct protocol *proto)
                if (listener->state != LI_INIT)
                        continue; /* already started */
 
-               fd = create_uxst_socket(((struct sockaddr_un *)&listener->addr)->sun_path);
+               fd = create_uxst_socket(((struct sockaddr_un *)&listener->addr)->sun_path,
+                                       listener->perm.ux.uid,
+                                       listener->perm.ux.gid,
+                                       listener->perm.ux.mode);
                if (fd == -1) {
                        err |= ERR_FATAL;
                        continue;