helpers: ftp: Avoid ugly casts

Coverity tool complains about accessing a local variable at non-zero
offset. Avoid this by using a helper union. This should silence the
checker, although the code is still probably not Big Endian-safe.

Signed-off-by: Phil Sutter <phil@nwl.cc>

1 files changed, 9 insertions, 11 deletions

diff --git a/src/helpers/ftp.c b/src/helpers/ftp.c
index 29ac55c..2b34534 100644
--- a/src/helpers/ftp.c
+++ b/src/helpers/ftp.c
@@ -332,23 +332,21 @@ static int nf_nat_ftp_fmt_cmd(enum nf_ct_ftp_type type,
 			      char *buffer, size_t buflen,
 			      uint32_t addr, uint16_t port)
 {
+	union {
+		unsigned char c[4];
+		uint32_t d;
+	} tmp;
+
+	tmp.d = addr;
 	switch (type) {
 	case NF_CT_FTP_PORT:
 	case NF_CT_FTP_PASV:
 		return snprintf(buffer, buflen, "%u,%u,%u,%u,%u,%u",
-				((unsigned char *)&addr)[0],
-				((unsigned char *)&addr)[1],
-				((unsigned char *)&addr)[2],
-				((unsigned char *)&addr)[3],
-				port >> 8,
-				port & 0xFF);
+				tmp.c[0], tmp.c[1], tmp.c[2], tmp.c[3],
+				port >> 8, port & 0xFF);
 	case NF_CT_FTP_EPRT:
 		return snprintf(buffer, buflen, "|1|%u.%u.%u.%u|%u|",
-				((unsigned char *)&addr)[0],
-				((unsigned char *)&addr)[1],
-				((unsigned char *)&addr)[2],
-				((unsigned char *)&addr)[3],
-				port);
+				tmp.c[0], tmp.c[1], tmp.c[2], tmp.c[3], port);
 	case NF_CT_FTP_EPSV:
 		return snprintf(buffer, buflen, "|||%u|", port);
 	}