[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/libbb/udp_io.c b/ap/app/busybox/src/libbb/udp_io.c
new file mode 100644
index 0000000..7985a97
--- /dev/null
+++ b/ap/app/busybox/src/libbb/udp_io.c
@@ -0,0 +1,179 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 2007 Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+#include "libbb.h"
+
+/*
+ * This asks kernel to let us know dst addr/port of incoming packets
+ * We don't check for errors here. Not supported == won't be used
+ */
+void FAST_FUNC
+socket_want_pktinfo(int fd UNUSED_PARAM)
+{
+#ifdef IP_PKTINFO
+	setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &const_int_1, sizeof(int));
+#endif
+#if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
+	setsockopt(fd, IPPROTO_IPV6, IPV6_PKTINFO, &const_int_1, sizeof(int));
+#endif
+}
+
+
+ssize_t FAST_FUNC
+send_to_from(int fd, void *buf, size_t len, int flags,
+		const struct sockaddr *to,
+		const struct sockaddr *from,
+		socklen_t tolen)
+{
+#ifndef IP_PKTINFO
+	(void)from; /* suppress "unused from" warning */
+	return sendto(fd, buf, len, flags, to, tolen);
+#else
+	struct iovec iov[1];
+	struct msghdr msg;
+	union {
+		char cmsg[CMSG_SPACE(sizeof(struct in_pktinfo))];
+# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
+		char cmsg6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+# endif
+	} u;
+	struct cmsghdr* cmsgptr;
+
+	if (from->sa_family != AF_INET
+# if ENABLE_FEATURE_IPV6
+	 && from->sa_family != AF_INET6
+# endif
+	) {
+		/* ANY local address */
+		return sendto(fd, buf, len, flags, to, tolen);
+	}
+
+	/* man recvmsg and man cmsg is needed to make sense of code below */
+
+	iov[0].iov_base = buf;
+	iov[0].iov_len = len;
+
+	memset(&u, 0, sizeof(u));
+
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_name = (void *)(struct sockaddr *)to; /* or compiler will annoy us */
+	msg.msg_namelen = tolen;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = &u;
+	msg.msg_controllen = sizeof(u);
+	msg.msg_flags = flags;
+
+	cmsgptr = CMSG_FIRSTHDR(&msg);
+	if (to->sa_family == AF_INET && from->sa_family == AF_INET) {
+		struct in_pktinfo *pktptr;
+		cmsgptr->cmsg_level = IPPROTO_IP;
+		cmsgptr->cmsg_type = IP_PKTINFO;
+		cmsgptr->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
+		pktptr = (struct in_pktinfo *)(CMSG_DATA(cmsgptr));
+		/*pktptr->ipi_ifindex = 0; -- already done by memset(u...) */
+		/* In general, CMSG_DATA() can be unaligned, but in this case
+		 * we know for sure it is sufficiently aligned:
+		 * CMSG_FIRSTHDR simply returns &u above,
+		 * and CMSG_DATA returns &u + size_t + int + int.
+		 * Thus direct assignment is ok:
+		 */
+		pktptr->ipi_spec_dst = ((struct sockaddr_in*)from)->sin_addr;
+	}
+# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
+	else if (to->sa_family == AF_INET6 && from->sa_family == AF_INET6) {
+		struct in6_pktinfo *pktptr;
+		cmsgptr->cmsg_level = IPPROTO_IPV6;
+		cmsgptr->cmsg_type = IPV6_PKTINFO;
+		cmsgptr->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
+		pktptr = (struct in6_pktinfo *)(CMSG_DATA(cmsgptr));
+		/* pktptr->ipi6_ifindex = 0; -- already done by memset(u...) */
+		pktptr->ipi6_addr = ((struct sockaddr_in6*)from)->sin6_addr;
+	}
+# endif
+	msg.msg_controllen = cmsgptr->cmsg_len;
+
+	return sendmsg(fd, &msg, flags);
+#endif
+}
+
+/* NB: this will never set port# in 'to'!
+ * _Only_ IP/IPv6 address part of 'to' is _maybe_ modified.
+ * Typical usage is to preinit 'to' with "default" value
+ * before calling recv_from_to(). */
+ssize_t FAST_FUNC
+recv_from_to(int fd, void *buf, size_t len, int flags,
+		struct sockaddr *from, struct sockaddr *to,
+		socklen_t sa_size)
+{
+#ifndef IP_PKTINFO
+	(void)to; /* suppress "unused to" warning */
+	return recvfrom(fd, buf, len, flags, from, &sa_size);
+#else
+	/* man recvmsg and man cmsg is needed to make sense of code below */
+	struct iovec iov[1];
+	union {
+		char cmsg[CMSG_SPACE(sizeof(struct in_pktinfo))];
+# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
+		char cmsg6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+# endif
+	} u;
+	struct cmsghdr *cmsgptr;
+	struct msghdr msg;
+	ssize_t recv_length;
+
+	iov[0].iov_base = buf;
+	iov[0].iov_len = len;
+
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_name = (struct sockaddr *)from;
+	msg.msg_namelen = sa_size;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = &u;
+	msg.msg_controllen = sizeof(u);
+
+	recv_length = recvmsg(fd, &msg, flags);
+	if (recv_length < 0)
+		return recv_length;
+
+# define to4 ((struct sockaddr_in*)to)
+# define to6 ((struct sockaddr_in6*)to)
+	/* Here we try to retrieve destination IP and memorize it */
+	for (cmsgptr = CMSG_FIRSTHDR(&msg);
+			cmsgptr != NULL;
+			cmsgptr = CMSG_NXTHDR(&msg, cmsgptr)
+	) {
+		if (cmsgptr->cmsg_level == IPPROTO_IP
+		 && cmsgptr->cmsg_type == IP_PKTINFO
+		) {
+			const int IPI_ADDR_OFF = offsetof(struct in_pktinfo, ipi_addr);
+			to->sa_family = AF_INET;
+			/*# define pktinfo(cmsgptr) ( (struct in_pktinfo*)(CMSG_DATA(cmsgptr)) )*/
+			/*to4->sin_addr = pktinfo(cmsgptr)->ipi_addr; - may be unaligned */
+			memcpy(&to4->sin_addr, (char*)(CMSG_DATA(cmsgptr)) + IPI_ADDR_OFF, sizeof(to4->sin_addr));
+			/*to4->sin_port = 123; - this data is not supplied by kernel */
+			break;
+		}
+# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
+		if (cmsgptr->cmsg_level == IPPROTO_IPV6
+		 && cmsgptr->cmsg_type == IPV6_PKTINFO
+		) {
+			const int IPI6_ADDR_OFF = offsetof(struct in6_pktinfo, ipi6_addr);
+			to->sa_family = AF_INET6;
+			/*#  define pktinfo(cmsgptr) ( (struct in6_pktinfo*)(CMSG_DATA(cmsgptr)) )*/
+			/*to6->sin6_addr = pktinfo(cmsgptr)->ipi6_addr; - may be unaligned */
+			memcpy(&to6->sin6_addr, (char*)(CMSG_DATA(cmsgptr)) + IPI6_ADDR_OFF, sizeof(to6->sin6_addr));
+			/*to6->sin6_port = 123; */
+			break;
+		}
+# endif
+	}
+	return recv_length;
+#endif
+}