summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMichal Sekletar <msekleta@redhat.com>2014-01-17 17:09:45 +0100
committerDavid S. Miller <davem@davemloft.net>2014-01-19 04:08:58 +0100
commitea02f9411d9faa3553ed09ce0ec9f00ceae9885e (patch)
treec058c0f3060402a8778ed077f7dc092e62fc0958
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net (diff)
downloadlinux-ea02f9411d9faa3553ed09ce0ec9f00ceae9885e.tar.xz
linux-ea02f9411d9faa3553ed09ce0ec9f00ceae9885e.zip
net: introduce SO_BPF_EXTENSIONS
For user space packet capturing libraries such as libpcap, there's currently only one way to check which BPF extensions are supported by the kernel, that is, commit aa1113d9f85d ("net: filter: return -EINVAL if BPF_S_ANC* operation is not supported"). For querying all extensions at once this might be rather inconvenient. Therefore, this patch introduces a new option which can be used as an argument for getsockopt(), and allows one to obtain information about which BPF extensions are supported by the current kernel. As David Miller suggests, we do not need to define any bits right now and status quo can just return 0 in order to state that this versions supports SKF_AD_PROTOCOL up to SKF_AD_PAY_OFFSET. Later additions to BPF extensions need to add their bits to the bpf_tell_extensions() function, as documented in the comment. Signed-off-by: Michal Sekletar <msekleta@redhat.com> Cc: David Miller <davem@davemloft.net> Reviewed-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat
-rw-r--r--arch/alpha/include/uapi/asm/socket.h2
-rw-r--r--arch/avr32/include/uapi/asm/socket.h2
-rw-r--r--arch/cris/include/uapi/asm/socket.h2
-rw-r--r--arch/frv/include/uapi/asm/socket.h2
-rw-r--r--arch/ia64/include/uapi/asm/socket.h2
-rw-r--r--arch/m32r/include/uapi/asm/socket.h2
-rw-r--r--arch/mips/include/uapi/asm/socket.h2
-rw-r--r--arch/mn10300/include/uapi/asm/socket.h2
-rw-r--r--arch/parisc/include/uapi/asm/socket.h2
-rw-r--r--arch/powerpc/include/uapi/asm/socket.h2
-rw-r--r--arch/s390/include/uapi/asm/socket.h2
-rw-r--r--arch/sparc/include/uapi/asm/socket.h2
-rw-r--r--arch/xtensa/include/uapi/asm/socket.h2
-rw-r--r--include/linux/filter.h11
-rw-r--r--include/uapi/asm-generic/socket.h2
-rw-r--r--net/core/sock.c4
16 files changed, 43 insertions, 0 deletions
diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h
index e3a1491d5073..3de1394bcab8 100644
--- a/arch/alpha/include/uapi/asm/socket.h
+++ b/arch/alpha/include/uapi/asm/socket.h
@@ -85,4 +85,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _UAPI_ASM_SOCKET_H */
diff --git a/arch/avr32/include/uapi/asm/socket.h b/arch/avr32/include/uapi/asm/socket.h
index cbf902e4cd9e..6e6cd159924b 100644
--- a/arch/avr32/include/uapi/asm/socket.h
+++ b/arch/avr32/include/uapi/asm/socket.h
@@ -78,4 +78,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _UAPI__ASM_AVR32_SOCKET_H */
diff --git a/arch/cris/include/uapi/asm/socket.h b/arch/cris/include/uapi/asm/socket.h
index 13829aaaeec5..ed94e5ed0a23 100644
--- a/arch/cris/include/uapi/asm/socket.h
+++ b/arch/cris/include/uapi/asm/socket.h
@@ -80,6 +80,8 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_SOCKET_H */
diff --git a/arch/frv/include/uapi/asm/socket.h b/arch/frv/include/uapi/asm/socket.h
index 5d4299762426..ca2c6e6f31c6 100644
--- a/arch/frv/include/uapi/asm/socket.h
+++ b/arch/frv/include/uapi/asm/socket.h
@@ -78,5 +78,7 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_SOCKET_H */
diff --git a/arch/ia64/include/uapi/asm/socket.h b/arch/ia64/include/uapi/asm/socket.h
index c25302fb48d9..a1b49bac7951 100644
--- a/arch/ia64/include/uapi/asm/socket.h
+++ b/arch/ia64/include/uapi/asm/socket.h
@@ -87,4 +87,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_IA64_SOCKET_H */
diff --git a/arch/m32r/include/uapi/asm/socket.h b/arch/m32r/include/uapi/asm/socket.h
index 52966650114f..6c9a24b3aefa 100644
--- a/arch/m32r/include/uapi/asm/socket.h
+++ b/arch/m32r/include/uapi/asm/socket.h
@@ -78,4 +78,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_M32R_SOCKET_H */
diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h
index 0df9787cd84d..a14baa218c76 100644
--- a/arch/mips/include/uapi/asm/socket.h
+++ b/arch/mips/include/uapi/asm/socket.h
@@ -96,4 +96,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _UAPI_ASM_SOCKET_H */
diff --git a/arch/mn10300/include/uapi/asm/socket.h b/arch/mn10300/include/uapi/asm/socket.h
index 71dedcae55a6..6aa3ce1854aa 100644
--- a/arch/mn10300/include/uapi/asm/socket.h
+++ b/arch/mn10300/include/uapi/asm/socket.h
@@ -78,4 +78,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_SOCKET_H */
diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h
index 70b3674dac4e..fe35ceacf0e7 100644
--- a/arch/parisc/include/uapi/asm/socket.h
+++ b/arch/parisc/include/uapi/asm/socket.h
@@ -77,4 +77,6 @@
#define SO_MAX_PACING_RATE 0x4028
+#define SO_BPF_EXTENSIONS 0x4029
+
#endif /* _UAPI_ASM_SOCKET_H */
diff --git a/arch/powerpc/include/uapi/asm/socket.h b/arch/powerpc/include/uapi/asm/socket.h
index fa698324a1fd..a9c3e2e18c05 100644
--- a/arch/powerpc/include/uapi/asm/socket.h
+++ b/arch/powerpc/include/uapi/asm/socket.h
@@ -85,4 +85,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_POWERPC_SOCKET_H */
diff --git a/arch/s390/include/uapi/asm/socket.h b/arch/s390/include/uapi/asm/socket.h
index c286c2e868f0..e031332096d7 100644
--- a/arch/s390/include/uapi/asm/socket.h
+++ b/arch/s390/include/uapi/asm/socket.h
@@ -84,4 +84,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _ASM_SOCKET_H */
diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h
index 0f21e9a5ca18..54d9608681b6 100644
--- a/arch/sparc/include/uapi/asm/socket.h
+++ b/arch/sparc/include/uapi/asm/socket.h
@@ -74,6 +74,8 @@
#define SO_MAX_PACING_RATE 0x0031
+#define SO_BPF_EXTENSIONS 0x0032
+
/* Security levels - as per NRL IPv6 - don't actually do anything */
#define SO_SECURITY_AUTHENTICATION 0x5001
#define SO_SECURITY_ENCRYPTION_TRANSPORT 0x5002
diff --git a/arch/xtensa/include/uapi/asm/socket.h b/arch/xtensa/include/uapi/asm/socket.h
index 7db5c22faa68..39acec0cf0b1 100644
--- a/arch/xtensa/include/uapi/asm/socket.h
+++ b/arch/xtensa/include/uapi/asm/socket.h
@@ -89,4 +89,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* _XTENSA_SOCKET_H */
diff --git a/include/linux/filter.h b/include/linux/filter.h
index ff4e40cd45b1..1a95a2dcf113 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -83,6 +83,17 @@ static inline void bpf_jit_free(struct sk_filter *fp)
#define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns)
#endif
+static inline int bpf_tell_extensions(void)
+{
+ /* When adding new BPF extension it is necessary to enumerate
+ * it here, so userspace software which wants to know what is
+ * supported can do so by inspecting return value of this
+ * function
+ */
+
+ return 0;
+}
+
enum {
BPF_S_RET_K = 1,
BPF_S_RET_A,
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index 38f14d0264c3..ea0796bdcf88 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -80,4 +80,6 @@
#define SO_MAX_PACING_RATE 47
+#define SO_BPF_EXTENSIONS 48
+
#endif /* __ASM_GENERIC_SOCKET_H */
diff --git a/net/core/sock.c b/net/core/sock.c
index b3f7ee3008a0..0c127dcdf6a8 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1167,6 +1167,10 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
break;
+ case SO_BPF_EXTENSIONS:
+ v.val = bpf_tell_extensions();
+ break;
+
case SO_SELECT_ERR_QUEUE:
v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
break;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-19 12:49:51 +0100