sock_probe_mem() currently checks whether we're able to allocate large
socket buffers. Extend it to also check whether the SO_BINDTODEVICE
socket option is available. Rename to sock_probe_features() to reflect the
new functionality.
Signed-off-by: David Gibson
---
passt.c | 2 +-
passt.h | 1 +
util.c | 19 +++++++++++++++++--
util.h | 2 +-
4 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/passt.c b/passt.c
index 4964427d..0b84ac6c 100644
--- a/passt.c
+++ b/passt.c
@@ -381,7 +381,7 @@ int main(int argc, char **argv)
if (setrlimit(RLIMIT_NOFILE, &limit))
die_perror("Failed to set current limit for open files");
- sock_probe_mem(&c);
+ sock_probe_features(&c);
conf(&c, argc, argv);
trace_init(c.trace);
diff --git a/passt.h b/passt.h
index 15801b44..e7c1710a 100644
--- a/passt.h
+++ b/passt.h
@@ -281,6 +281,7 @@ struct ctx {
int low_wmem;
int low_rmem;
+ int no_bindtodevice;
struct vu_dev *vdev;
diff --git a/util.c b/util.c
index 347f34f5..bad38129 100644
--- a/util.c
+++ b/util.c
@@ -233,12 +233,13 @@ int sock_unix(char *sock_path)
}
/**
- * sock_probe_mem() - Check if setting high SO_SNDBUF and SO_RCVBUF is allowed
+ * sock_probe_features() - Probe for socket features we might use
* @c: Execution context
*/
-void sock_probe_mem(struct ctx *c)
+void sock_probe_features(struct ctx *c)
{
int v = INT_MAX / 2, s;
+ const char lo[] = "lo";
socklen_t sl;
s = socket(AF_INET, SOCK_STREAM | SOCK_CLOEXEC, IPPROTO_TCP);
@@ -247,6 +248,7 @@ void sock_probe_mem(struct ctx *c)
return;
}
+ /* Check if setting high SO_SNDBUF and SO_RCVBUF is allowed */
sl = sizeof(v);
if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, sizeof(v)) ||
getsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, &sl) ||
@@ -259,6 +261,19 @@ void sock_probe_mem(struct ctx *c)
(size_t)v < RCVBUF_BIG)
c->low_rmem = 1;
+ /* Check if SO_BINDTODEVICE is available
+ *
+ * Supported since kernel version 5.7, commit c427bfec18f2 ("net: core:
+ * enable SO_BINDTODEVICE for non-root users"). Some distro kernels may
+ * have backports, of course. Record whether we can use it so that we
+ * can give more useful diagnostics.
+ */
+ if (setsockopt(s, SOL_SOCKET, SO_BINDTODEVICE, lo, sizeof(lo)-1)) {
+ if (errno != EPERM)
+ warn_perror("Unexpected error probing SO_BINDTODEVICE");
+ c->no_bindtodevice = 1;
+ }
+
close(s);
}
diff --git a/util.h b/util.h
index a0b2ada6..200b6408 100644
--- a/util.h
+++ b/util.h
@@ -211,7 +211,7 @@ int sock_l4_sa(const struct ctx *c, enum epoll_type type,
const void *sa, socklen_t sl,
const char *ifname, bool v6only);
int sock_unix(char *sock_path);
-void sock_probe_mem(struct ctx *c);
+void sock_probe_features(struct ctx *c);
long timespec_diff_ms(const struct timespec *a, const struct timespec *b);
int64_t timespec_diff_us(const struct timespec *a, const struct timespec *b);
void bitmap_set(uint8_t *map, unsigned bit);
--
2.51.1