Add a function for dumping iovec in msghdr used in sendmsg and recvmsg
Here is an example session:
$ ./strace -e write=all ip link change dev enp0s25 mtu 1501 > /dev/null
sendmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"(...
* 40 bytes in buffer 0
| 00000 28 00 00 00 10 00 05 00 d0 d9 aa 53 00 00 00 00 (..........S.... |
| 00010 00 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ................ |
| 00020 08 00 04 00 dd 05 00 00 ........ |
...
$ ./strace -e read=all ip link show > /dev/null
recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"...
* 8192 bytes in buffer 0
| 00000 34 00 00 00 02 00 00 00 00 00 00 00 ff 23 00 00 4............#.. |
| 00010 ff ff ff ff 20 00 00 00 10 00 05 00 00 00 00 00 .... ........... |
...
* defs.h (dumpiov_in_msghdr): New prototype.
* net.c (extractmsghdr): New function derived from printmsghdr.
(printmsghdr): Use extractmsghdr.
(dumpiov_in_msghdr): New function.
* syscall.c (dumpio) [HAVE_SENDMSG]: Call dumpiov_in_msghdr for recvmsg
and sendmsg syscalls.
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
diff --git a/net.c b/net.c
index 46c491f..a0e90a8 100644
--- a/net.c
+++ b/net.c
@@ -392,33 +392,47 @@
uint32_t /* unsigned */ msg_len;
};
+static bool
+extractmsghdr(struct tcb *tcp, long addr, struct msghdr *msg)
+{
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+ if (current_wordsize == 4) {
+ struct msghdr32 msg32;
+
+ if (umove(tcp, addr, &msg32) < 0)
+ return false;
+ msg->msg_name = (void*)(long)msg32.msg_name;
+ msg->msg_namelen = msg32.msg_namelen;
+ msg->msg_iov = (void*)(long)msg32.msg_iov;
+ msg->msg_iovlen = msg32.msg_iovlen;
+ msg->msg_control = (void*)(long)msg32.msg_control;
+ msg->msg_controllen = msg32.msg_controllen;
+ msg->msg_flags = msg32.msg_flags;
+ } else
+#endif
+ if (umove(tcp, addr, msg) < 0)
+ return false;
+ return true;
+}
+
static void
printmsghdr(struct tcb *tcp, long addr, unsigned long data_size)
{
struct msghdr msg;
-#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
- if (current_wordsize == 4) {
- struct msghdr32 msg32;
-
- if (umove(tcp, addr, &msg32) < 0) {
- tprintf("%#lx", addr);
- return;
- }
- msg.msg_name = (void*)(long)msg32.msg_name;
- msg.msg_namelen = msg32.msg_namelen;
- msg.msg_iov = (void*)(long)msg32.msg_iov;
- msg.msg_iovlen = msg32.msg_iovlen;
- msg.msg_control = (void*)(long)msg32.msg_control;
- msg.msg_controllen = msg32.msg_controllen;
- msg.msg_flags = msg32.msg_flags;
- } else
-#endif
- if (umove(tcp, addr, &msg) < 0) {
+ if (extractmsghdr(tcp, addr, &msg))
+ do_msghdr(tcp, &msg, data_size);
+ else
tprintf("%#lx", addr);
- return;
- }
- do_msghdr(tcp, &msg, data_size);
+}
+
+void
+dumpiov_in_msghdr(struct tcb *tcp, long addr)
+{
+ struct msghdr msg;
+
+ if (extractmsghdr(tcp, addr, &msg))
+ dumpiov(tcp, msg.msg_iovlen, (long)msg.msg_iov);
}
static void