git: ee951eb59f21 - main - socket: Add an option to retrieve a socket's FIB number

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=ee951eb59f2136a604e3fbb12abf8d8344da0c99

commit ee951eb59f2136a604e3fbb12abf8d8344da0c99
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-02-06 14:17:19 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2025-02-06 14:17:19 +0000

    socket: Add an option to retrieve a socket's FIB number
    
    The SO_SETFIB option can be used to set a socket's FIB number, but there
    is no way to retrieve it.  Rename SO_SETFIB to SO_FIB and implement a
    handler for it for getsockopt(2).
    
    Reviewed by:    glebius
    MFC after:      2 weeks
    Sponsored by:   Klara, Inc.
    Sponsored by:   Stormshield
    Differential Revision:  https://reviews.freebsd.org/D48834
---
 lib/libsys/getsockopt.2 | 4 ++--
 sys/kern/uipc_socket.c  | 6 ++++++
 sys/sys/socket.h        | 3 ++-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/libsys/getsockopt.2 b/lib/libsys/getsockopt.2
index 15e4b76311d8..619540b53fae 100644
--- a/lib/libsys/getsockopt.2
+++ b/lib/libsys/getsockopt.2
@@ -175,7 +175,7 @@ for the socket
 .It Dv SO_PROTOTYPE Ta "SunOS alias for the Linux SO_PROTOCOL (get only)"
 .It Dv SO_ERROR Ta "get and clear error on the socket (get only)"
 .It Dv SO_RERROR Ta "enables receive error reporting"
-.It Dv SO_SETFIB Ta "set the associated FIB (routing table) for the socket (set only)"
+.It Dv SO_FIB Ta "get or set the associated FIB (routing table) for the socket"
 .El
 .Pp
 The following options are recognized in
@@ -358,7 +358,7 @@ or with the error
 .Er EWOULDBLOCK
 if no data were received.
 .Pp
-.Dv SO_SETFIB
+.Dv SO_FIB
 can be used to over-ride the default FIB (routing table) for the given socket.
 The value must be from 0 to one less than the number returned from
 the sysctl
diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index 65cea2e067cf..03bfea721dd2 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -4106,6 +4106,12 @@ integer:
 			error = sooptcopyout(sopt, &optval, sizeof optval);
 			break;
 
+		case SO_FIB:
+			SOCK_LOCK(so);
+			optval = so->so_fibnum;
+			SOCK_UNLOCK(so);
+			goto integer;
+
 		case SO_DOMAIN:
 			optval = so->so_proto->pr_domain->dom_family;
 			goto integer;
diff --git a/sys/sys/socket.h b/sys/sys/socket.h
index cc82d97e9dd5..2ef455991491 100644
--- a/sys/sys/socket.h
+++ b/sys/sys/socket.h
@@ -164,7 +164,8 @@ typedef	__uintptr_t	uintptr_t;
 #define	SO_LISTENQLIMIT	0x1011		/* socket's backlog limit */
 #define	SO_LISTENQLEN	0x1012		/* socket's complete queue length */
 #define	SO_LISTENINCQLEN	0x1013	/* socket's incomplete queue length */
-#define	SO_SETFIB	0x1014		/* use this FIB to route */
+#define	SO_FIB		0x1014		/* get or set socket FIB */
+#define	SO_SETFIB	SO_FIB		/* backward compat alias */
 #define	SO_USER_COOKIE	0x1015		/* user cookie (dummynet etc.) */
 #define	SO_PROTOCOL	0x1016		/* get socket protocol (Linux name) */
 #define	SO_PROTOTYPE	SO_PROTOCOL	/* alias for SO_PROTOCOL (SunOS name) */