path: root/net/wmnet/files/patch-if.c

--- if.c.orig   1998-10-12 06:13:16.000000000 +0400
+++ if.c    2014-10-02 21:48:19.000000000 +0400
@@ -11,32 +11,28 @@
 #include <string.h>
 #include <unistd.h>
 #include <limits.h>
+#include <errno.h>
 #include <err.h>
 #include <sys/param.h>
 #include <sys/types.h>
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <net/if.h>
-#if (__FreeBSD_version >= 300003)
-#include <net/if_var.h>
 #include <net/if_types.h>
-#endif
 #include <fcntl.h>
-#include <kvm.h>
-#include <nlist.h>
 #include <assert.h>
+#include <ifaddrs.h>
 #include "wmnet.h"
 
 #define    IF_STEP 10
+#define    IFA_STAT(s) (((struct if_data *)ifa->ifa_data)->ifi_ ## s)
 
 /*
    Local data types...
 */
 typedef struct {
-   unsigned long ifNetAddr;
-
+   char name[IFNAMSIZ];
    unsigned long flags;
-
    unsigned current;
    unsigned long xmt[G_WIDTH], xmtLast;
    unsigned long rcv[G_WIDTH], rcvLast;
@@ -45,19 +41,15 @@
 /*
    Local prototypes...
 */
-static int addIfData(unsigned long);
-static struct ifnet const* dereference(unsigned long);
-static void ifTerm(void);
+static int addIfData(struct ifaddrs *);
 
 /*
    Local data...
 */
-static kvm_t* kd = 0;
-static unsigned long root = 0;
-
 static int total = 0;
 static int size = 0;
 static IfData* ifData = 0;
+static int sock;
 
 /*------------------------------------------------------------------------------
    addIfData
@@ -66,134 +58,57 @@
    out of space, more space is allocated. If the interface already
    exists in the list, we don't do anything.
 ------------------------------------------------------------------------------*/
-static int addIfData(unsigned long theAddr)
+static int addIfData(struct ifaddrs *ifa)
 {
-   struct ifnet const* const theData = dereference(theAddr);
+   IfData* ptr = 0;
+   int ii;
 
    assert(total <= size);
 
-   /* Now read in the data so we can get to some of its goodies. */
-
-   if (0 != theData) {
-       IfData* ptr = 0;
-       int ii;
-
-       /* First check to see if we have enough space in the list. If
-          we don't, we'll have to add more space. */
-
-       if (total == size) {
-           IfData* const newData =
-               (IfData*) realloc(ifData,
-                                 (size += IF_STEP) * sizeof(IfData));
-
-           if (!newData) {
-               size -= IF_STEP;
-               fprintf(stderr, "wmnet: Warning -- low memory; "
-                       "ignoring %s interface\n", theData->if_name);
-               return 0;
-           }
-
-           /* Good. we got more space. */
-
-           ifData = newData;
+   /* First check to see if we have enough space in the list. If
+      we don't, we'll have to add more space. */
+   if (total == size) {
+       IfData *newData;
+
+       newData = realloc(ifData, (size += IF_STEP) * sizeof(IfData));
+
+       if (!newData) {
+           size -= IF_STEP;
+           fprintf(stderr, "wmnet: Warning -- low memory; "
+               "ignoring %s interface\n", ifa->ifa_name);
+           return ENOMEM;
        }
 
-       assert(0 != ifData);
-       assert(total < size);
-
-       /* If we reached here, then 'total' points to the next
-          bucket. Initialize the new bucket. XXX: This would be a
-          good spot to insert-sort the new record. As it stands, the
-          list builds up by the order that the interfaces were
-          bootstrapped. */
-
-       ptr = ifData + total;
-
-       ptr->ifNetAddr = theAddr;
-       for (ii = 0; ii < G_WIDTH; ++ii)
-           ptr->rcv[ii] = ptr->xmt[ii] = 0;
-       ptr->rcvLast = theData->if_ibytes;
-       ptr->xmtLast = theData->if_obytes;
-       ptr->current = 0;
-       ptr->flags = 0;
-
-#ifndef NDEBUG
-       printf("Added '%.*s%d' to list.\n", IFNAMSIZ, theData->if_name,
-              theData->if_unit);
-#endif
-
-       // Bump the total.
-
-       ++total;
-   } else
-       fprintf(stderr, "Couldn't read interface information\n");
-   return 1;
-}
-
-/*------------------------------------------------------------------------------
-   dereference
-
-   Takes the kernel memory "pointer" and copies its pointed-to data
-   into a local buffer. The only type of "pointer" we're using is a
-   struct ifnet*, so this function only returns this type of data.
-
-   Passing in 0 will reset the address cache and force the function
-   to reload the data.
-------------------------------------------------------------------------------*/
-static struct ifnet const* dereference(unsigned long a)
-{
-   static unsigned long c = 0;
-   static struct ifnet d;
-   static char name[IFNAMSIZ];
-
-   /* If we are passed a NULL, the caller wants us to stop caching
-      the current interface. */
-
-   if (!a) {
-       c = 0;
-       return 0;
+       /* Good. we got more space. */
+       ifData = newData;
    }
 
-   /* If the requested address is the same that has been cached, just
-      return the data. */
+   assert(0 != ifData);
+   assert(total < size);
 
-   else if (a == c)
-       return &d;
-   else if (sizeof(d) == kvm_read(kd, a, &d, sizeof(d))) {
-
-       /* We've read the structure's data, but the 'name' field still
-          points to kernel memory. We transfer the name to a local
-          buffer, and then modify the pointer to point to our
-          buffer. */
-
-       ssize_t const n =  kvm_read(kd, (unsigned long) d.if_name, name,
-                                   sizeof(name));
-
-       if (sizeof(name) == n) {
-           name[IFNAMSIZ - 1] = '\0';
-           d.if_name = name;
-#ifndef NDEBUG
+   /* If we reached here, then 'total' points to the next
+      bucket. Initialize the new bucket. XXX: This would be a
+      good spot to insert-sort the new record. As it stands, the
+      list builds up by the order that the interfaces were
+      bootstrapped. */
+
+   ptr = ifData + total;
+
+   strncpy(ptr->name, ifa->ifa_name, IFNAMSIZ);
+   for (ii = 0; ii < G_WIDTH; ++ii)
+       ptr->rcv[ii] = ptr->xmt[ii] = 0;
+   ptr->rcvLast = IFA_STAT(ibytes);
+   ptr->xmtLast = IFA_STAT(obytes);
+   ptr->current = 0;
+   ptr->flags = 0;
 
-           /* These are other pointer fields that we shouldn't need
-              to look at. While debugging, set these to NULL to trap
-              any attempts. */
-
-           d.if_softc = 0;
-#if (__FreeBSD_version >= 300003)
-           d.if_addrhead.tqh_first = 0;
-#else
-           d.if_addrlist = 0;
-#endif
-           d.if_bpf = 0;
-           d.if_linkmib = 0;
-           d.if_poll_slowq = 0;
+#ifndef NDEBUG
+   printf("Added '%.*s' to list.\n", IFNAMSIZ, ifa->ifa_name);
 #endif
-           c = a;
-           return &d;
-       } else
-           return 0;
-   } else
-       return 0;
+   // Bump the total.
+   ++total;
+
+   return 0;
 }
 
 /*------------------------------------------------------------------------------
@@ -222,56 +137,30 @@
 ------------------------------------------------------------------------------*/
 int ifInit(void)
 {
-   char errBuf[_POSIX2_LINE_MAX];
+   struct ifaddrs *ifap, *ifa;
 
-   /* First try to open the kernel image. If we can't, the rest of
-      the program is essentially useless. */
+   sock = socket(AF_INET, SOCK_DGRAM, 0);
+   if (sock < 0)
+       fprintf(stderr, "socket(): %d\n", errno);
+
+   if (getifaddrs(&ifap) != 0) {
+       fprintf(stderr, "getifaddrs(): %d\n", errno);
+       return (errno);
+   }
 
-   if (0 != (kd = kvm_openfiles(0, 0, 0, O_RDONLY, errBuf))) {
-       static struct nlist nl[] = {
-           { "_ifnet" },
-           { "" }
-       };
-
-       /* Try to pull the address for the global kernel variable,
-          ifnet. This variable is the root of the singly-linked list
-          of network interfaces. */
-
-       if (0 == kvm_nlist(kd, nl)) {
-           ssize_t const n = kvm_read(kd, nl[0].n_value, &root, sizeof(root));
-
-           /* We'll go ahead and make one dereference. We never
-              really want this variable. We want what it points to. */
-
-           if (sizeof(root) == n) {
-               unsigned long current = root;
-
-               while (current) {
-                   addIfData(current);
-#if (__FreeBSD_version >= 300003)
-                   current = (unsigned long) dereference(current)->if_link.tqe_next;
-#else
-                   current = (unsigned long) dereference(current)->if_next;
-#endif
-               }
+   for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
+       int error;
 
-               /* Try to register our termination function. If it
-                  returns an error, we essentially ignore it because
-                  the OS will clean up our resources. */
-
-               (void) atexit(ifTerm);
-               return 1;
-           }
+       if (ifa->ifa_addr->sa_family != AF_LINK)
+           continue;
+       if ((error = addIfData(ifa)) != 0) {
+           freeifaddrs(ifap);
+           return (error);
        }
+   }
 
-       /* If we can't get a symbol list, close the kernel image and
-          return an error. */
-
-       kvm_close(kd);
-       kd = 0;
-   } else
-       fprintf(stderr, "kvm_open: %s\n", errBuf);
-   return 0;
+   freeifaddrs(ifap);
+   return (0);
 }
 
 /*------------------------------------------------------------------------------
@@ -303,17 +192,7 @@
 ------------------------------------------------------------------------------*/
 char const* ifName(unsigned idx)
 {
-   if (idx < total) {
-       struct ifnet const* const ptr = dereference(ifData[idx].ifNetAddr);
-
-       if (ptr) {
-           static char buffer[IFNAMSIZ + 1];
-
-           sprintf(buffer, "%.*s%d", IFNAMSIZ - 1, ptr->if_name, ptr->if_unit);
-           return buffer;
-       }
-   }
-   return 0;
+   return ifData[idx].name;
 }
 
 /*------------------------------------------------------------------------------
@@ -324,68 +203,53 @@
 ------------------------------------------------------------------------------*/
 int ifSample(void)
 {
+   struct ifaddrs *ifap;
    int ii;
 
-   /* Flush the kernel memory cache so that we're guaranteed to get
-      new data during the next dereference(). */
-
-   dereference(0);
+   if (getifaddrs(&ifap) != 0) {
+       fprintf(stderr, "getifaddrs(): %d\n", errno);
+       return (errno);
+   }
 
    /* Loop through all the network interfaces. Even though we display
       one interface's statistics, we keep track of all of them. */
-
    for (ii = 0; ii < total; ++ii) {
-       IfData* const d = ifData + ii;
-       struct ifnet const* const ptr = dereference(d->ifNetAddr);
-
-       if (!ptr) {
-           fprintf(stderr, "couldn't sample interface.\n");
-           return 0;
-       }
-
-       d->flags = ptr->if_flags;
+       struct ifreq ifr;
+       struct ifaddrs *ifa;
+       IfData *d;
+
+       d = ifData + ii;
+
+       for (ifa = ifap; ifa; ifa = ifa->ifa_next)
+           if (ifa->ifa_addr->sa_family == AF_LINK &&
+               strcmp(ifa->ifa_name, d->name) == 0)
+               break;
+
+       if (ifa == NULL)
+           /* Interface disappeared? */
+           continue;
 
        /* Save the new delta for the transmit channel. */
-
-       d->xmt[d->current] = ptr->if_obytes - d->xmtLast;
-       d->xmtLast = ptr->if_obytes;
+       d->xmt[d->current] = IFA_STAT(obytes) - d->xmtLast;
+       d->xmtLast = IFA_STAT(obytes);
 
        /* Save the new delta for the receive channel. */
-
-       d->rcv[d->current] = ptr->if_ibytes - d->rcvLast;
-       d->rcvLast = ptr->if_ibytes;
+       d->rcv[d->current] = IFA_STAT(ibytes) - d->rcvLast;
+       d->rcvLast = IFA_STAT(ibytes);
 
        /* Prep the index for the next location to be written. */
-
        d->current = (d->current + 1) % G_WIDTH;
-   }
-   return 1;
-}
-
-/*------------------------------------------------------------------------------
-   ifTerm
 
-   This function will be called once when the application is ready to exit
-------------------------------------------------------------------------------*/
-static void ifTerm(void)
-{
-#ifndef NDEBUG
-   printf("Cleaning up resources.\n");
-#endif
-
-   /* If the kernel image is open, close it. */
-
-   if (0 != kd) {
-       kvm_close(kd);
-       kd = 0;
+       memset(&ifr, 0, sizeof(ifr));
+       strncpy(ifr.ifr_name, ifa->ifa_name, sizeof(ifr.ifr_name));
+       if (ioctl(sock, SIOCGIFFLAGS, (caddr_t)&ifr) < 0)
+           continue;
+       d->flags = (ifr.ifr_flags & 0xffff) | (ifr.ifr_flagshigh << 16);
    }
 
-   /* Now free up any memory we're using. */
+   freeifaddrs(ifap);
 
-   if (ifData) {
-       free(ifData);
-       ifData = 0;
-   }
+   return (0);
 }
 
 /*------------------------------------------------------------------------------