Changeset 2725 in MondoRescue for branches/2.2.9/mindi-busybox/libbb/udp_io.c

Timestamp:

Feb 25, 2011, 9:26:54 PM (13 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.18.3 to avoid problems with the tar command which is now failing on recent versions with busybox 1.7.3

File:

• branches/2.2.9/mindi-busybox/libbb/udp_io.c (modified) (12 diffs)

branches/2.2.9/mindi-busybox/libbb/udp_io.c

@@ -3 +3 @@
  * Utility routines.
  *
- * Copyright (C) 2007 Denis Vlasenko
+ * Copyright (C) 2007 Denys Vlasenko
  *
- * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
-
 #include "libbb.h"
 
@@ -14 +13 @@
  * We don't check for errors here. Not supported == won't be used
  */
-void
+void FAST_FUNC
 socket_want_pktinfo(int fd)
 {
@@ -26 +25 @@
 
 
-#ifdef UNUSED
-ssize_t
+ssize_t FAST_FUNC
 send_to_from(int fd, void *buf, size_t len, int flags,
-        const struct sockaddr *from, const struct sockaddr *to,
+        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;
-    char cbuf[sizeof(struct in_pktinfo)
-#if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
-        | sizeof(struct in6_pktinfo) /* (a|b) is poor man's max(a,b) */
-#endif
-    ];
+    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
+# if ENABLE_FEATURE_IPV6
      && from->sa_family != AF_INET6
-#endif
+# endif
     ) {
         /* ANY local address */
@@ -58 +59 @@
     iov[0].iov_len = len;
 
-    memset(cbuf, 0, sizeof(cbuf));
+    memset(&u, 0, sizeof(u));
 
     memset(&msg, 0, sizeof(msg));
@@ -65 +66 @@
     msg.msg_iov = iov;
     msg.msg_iovlen = 1;
-    msg.msg_control = cbuf;
-    msg.msg_controllen = sizeof(cbuf);
+    msg.msg_control = &u;
+    msg.msg_controllen = sizeof(u);
     msg.msg_flags = flags;
 
@@ -76 +77 @@
         cmsgptr->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
         pktptr = (struct in_pktinfo *)(CMSG_DATA(cmsgptr));
-        /* pktptr->ipi_ifindex = 0; -- already done by memset(cbuf...) */
+        /*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)
+# if ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
     else if (to->sa_family == AF_INET6 && from->sa_family == AF_INET6) {
         struct in6_pktinfo *pktptr;
@@ -86 +93 @@
         cmsgptr->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
         pktptr = (struct in6_pktinfo *)(CMSG_DATA(cmsgptr));
-        /* pktptr->ipi6_ifindex = 0; -- already done by memset(cbuf...) */
+        /* pktptr->ipi6_ifindex = 0; -- already done by memset(u...) */
         pktptr->ipi6_addr = ((struct sockaddr_in6*)from)->sin6_addr;
     }
-#endif
+# endif
+    msg.msg_controllen = cmsgptr->cmsg_len;
+
     return sendmsg(fd, &msg, flags);
 #endif
 }
-#endif /* UNUSED */
 
 /* NB: this will never set port# in 'to'!
@@ -99 +107 @@
  * Typical usage is to preinit 'to' with "default" value
  * before calling recv_from_to(). */
-ssize_t
+ssize_t FAST_FUNC
 recv_from_to(int fd, void *buf, size_t len, int flags,
         struct sockaddr *from, struct sockaddr *to,
@@ -105 +113 @@
 {
 #ifndef IP_PKTINFO
+    (void)to; /* suppress "unused to" warning */
     return recvfrom(fd, buf, len, flags, from, &sa_size);
 #else
@@ -111 +120 @@
     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;
-    socklen_t recv_length;
+    ssize_t recv_length;
 
     iov[0].iov_base = buf;
@@ -132 +143 @@
         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);
@@ -140 +153 @@
          && cmsgptr->cmsg_type == IP_PKTINFO
         ) {
-#define pktinfo(cmsgptr) ( (struct in_pktinfo*)(CMSG_DATA(cmsgptr)) )
+            const int IPI_ADDR_OFF = offsetof(struct in_pktinfo, ipi_addr);
             to->sa_family = AF_INET;
-            ((struct sockaddr_in*)to)->sin_addr = pktinfo(cmsgptr)->ipi_addr;
-            /* ((struct sockaddr_in*)to)->sin_port = 123; */
-#undef pktinfo
+            /*# 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 ENABLE_FEATURE_IPV6 && defined(IPV6_PKTINFO)
         if (cmsgptr->cmsg_level == IPPROTO_IPV6
          && cmsgptr->cmsg_type == IPV6_PKTINFO
         ) {
-#define pktinfo(cmsgptr) ( (struct in6_pktinfo*)(CMSG_DATA(cmsgptr)) )
+            const int IPI6_ADDR_OFF = offsetof(struct in6_pktinfo, ipi6_addr);
             to->sa_family = AF_INET6;
-            ((struct sockaddr_in6*)to)->sin6_addr = pktinfo(cmsgptr)->ipi6_addr;
-            /* ((struct sockaddr_in6*)to)->sin6_port = 123; */
-#undef pktinfo
+            /*#  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
+# endif
     }
     return recv_length;