networking/interface.c: was doing really strange caching of fd's

open for getting ifconfig data - ??! Simplified all that. -200 bytes.

1 files changed, 112 insertions, 199 deletions

diff --git a/networking/interface.c b/networking/interface.c
index 262b97879..2c5f3284e 100644
--- a/networking/interface.c
+++ b/networking/interface.c
@@ -36,7 +36,7 @@
 #include "inet_common.h"
 #include "busybox.h"
 
-#ifdef CONFIG_FEATURE_IPV6
+#if ENABLE_FEATURE_IPV6
 # define HAVE_AFINET6 1
 #else
 # undef HAVE_AFINET6
@@ -154,14 +154,13 @@ static int INET_input(/*int type,*/ const char *bufp, struct sockaddr *sap)
 */
 }
 
-static struct aftype inet_aftype = {
+static const struct aftype inet_aftype = {
         .name =         "inet",
         .title =        "DARPA Internet",
         .af =           AF_INET,
         .alen =         4,
         .sprint =       INET_sprint,
         .input =        INET_input,
-        .fd =           -1
 };
 
 #ifdef HAVE_AFINET6
@@ -208,14 +207,13 @@ static int INET6_input(/*int type,*/ const char *bufp, struct sockaddr *sap)
 */
 }
 
-static struct aftype inet6_aftype = {
+static const struct aftype inet6_aftype = {
         .name =         "inet6",
         .title =        "IPv6",
         .af =           AF_INET6,
         .alen =         sizeof(struct in6_addr),
         .sprint =       INET6_sprint,
         .input =        INET6_input,
-        .fd =           -1
 };
 
 #endif /* HAVE_AFINET6 */
@@ -246,13 +244,16 @@ static const char *UNSPEC_sprint(struct sockaddr *sap, int numeric)
         return UNSPEC_print((unsigned char *)sap->sa_data);
 }
 
-static struct aftype unspec_aftype = {
-        "unspec", "UNSPEC", AF_UNSPEC, 0,
-        UNSPEC_print, UNSPEC_sprint, NULL, NULL,
-        NULL,
+static const struct aftype unspec_aftype = {
+        .name   = "unspec",
+        .title  = "UNSPEC",
+        .af     = AF_UNSPEC,
+        .alen    = 0,
+        .print  = UNSPEC_print,
+        .sprint = UNSPEC_sprint,
 };
 
-static struct aftype * const aftypes[] = {
+static const struct aftype *const aftypes[] = {
         &inet_aftype,
 #ifdef HAVE_AFINET6
         &inet6_aftype,
@@ -262,9 +263,9 @@ static struct aftype * const aftypes[] = {
 };
 
 /* Check our protocol family table for this family. */
-struct aftype *get_aftype(const char *name)
+const struct aftype *get_aftype(const char *name)
 {
-        struct aftype * const *afp;
+        const struct aftype *const *afp;
 
         afp = aftypes;
         while (*afp != NULL) {
@@ -276,9 +277,9 @@ struct aftype *get_aftype(const char *name)
 }
 
 /* Check our protocol family table for this family. */
-static struct aftype *get_afntype(int af)
+static const struct aftype *get_afntype(int af)
 {
-        struct aftype * const *afp;
+        const struct aftype *const *afp;
 
         afp = aftypes;
         while (*afp != NULL) {
@@ -289,20 +290,6 @@ static struct aftype *get_afntype(int af)
         return NULL;
 }
 
-/* Check our protocol family table for this family and return its socket */
-static int get_socket_for_af(int af)
-{
-        struct aftype * const *afp;
-
-        afp = aftypes;
-        while (*afp != NULL) {
-                if ((*afp)->af == af)
-                        return (*afp)->fd;
-                afp++;
-        }
-        return -1;
-}
-
 struct user_net_device_stats {
         unsigned long long rx_packets;  /* total packets received       */
         unsigned long long tx_packets;  /* total packets transmitted    */
@@ -357,62 +344,8 @@ struct interface {
 int interface_opt_a;    /* show all interfaces          */
 
 static struct interface *int_list, *int_last;
-static int skfd = -1;   /* generic raw socket desc.     */
-
-
-static int sockets_open(int family)
-{
-        struct aftype * const *aft;
-        int sfd = -1;
-        static int force = -1;
-
-        if (force < 0) {
-                force = 0;
-                if (get_linux_version_code() < KERNEL_VERSION(2,1,0))
-                        force = 1;
-                if (access("/proc/net", R_OK))
-                        force = 1;
-        }
-        for (aft = aftypes; *aft; aft++) {
-                struct aftype *af = *aft;
-                int type = SOCK_DGRAM;
 
-                if (af->af == AF_UNSPEC)
-                        continue;
-                if (family && family != af->af)
-                        continue;
-                if (af->fd != -1) {
-                        sfd = af->fd;
-                        continue;
-                }
-                /* Check some /proc file first to not stress kmod */
-                if (!family && !force && af->flag_file) {
-                        if (access(af->flag_file, R_OK))
-                                continue;
-                }
-                af->fd = socket(af->af, type, 0);
-                if (af->fd >= 0)
-                        sfd = af->fd;
-        }
-        if (sfd < 0) {
-                bb_error_msg("no usable address families found");
-        }
-        return sfd;
-}
 
-#ifdef CONFIG_FEATURE_CLEAN_UP
-static void sockets_close(void)
-{
-        struct aftype * const *aft;
-        for (aft = aftypes; *aft != NULL; aft++) {
-                struct aftype *af = *aft;
-                if( af->fd != -1 ) {
-                        close(af->fd);
-                        af->fd = -1;
-                }
-        }
-}
-#endif
 #if 0
 /* like strcmp(), but knows about numbers */
 except that the freshly added calls to xatoul() brf on ethernet aliases with
@@ -467,55 +400,6 @@ static struct interface *add_interface(char *name)
         return new;
 }
 
-
-static int if_readconf(void)
-{
-        int numreqs = 30;
-        struct ifconf ifc;
-        struct ifreq *ifr;
-        int n, err = -1;
-        int skfd2;
-
-        /* SIOCGIFCONF currently seems to only work properly on AF_INET sockets
-           (as of 2.1.128) */
-        skfd2 = get_socket_for_af(AF_INET);
-        if (skfd2 < 0) {
-                bb_perror_msg(("warning: no inet socket available"));
-                /* Try to soldier on with whatever socket we can get hold of.  */
-                skfd2 = sockets_open(0);
-                if (skfd2 < 0)
-                        return -1;
-        }
-
-        ifc.ifc_buf = NULL;
-        for (;;) {
-                ifc.ifc_len = sizeof(struct ifreq) * numreqs;
-                ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);
-
-                if (ioctl(skfd2, SIOCGIFCONF, &ifc) < 0) {
-                        perror("SIOCGIFCONF");
-                        goto out;
-                }
-                if (ifc.ifc_len == sizeof(struct ifreq) * numreqs) {
-                        /* assume it overflowed and try again */
-                        numreqs += 10;
-                        continue;
-                }
-                break;
-        }
-
-        ifr = ifc.ifc_req;
-        for (n = 0; n < ifc.ifc_len; n += sizeof(struct ifreq)) {
-                add_interface(ifr->ifr_name);
-                ifr++;
-        }
-        err = 0;
-
-  out:
-        free(ifc.ifc_buf);
-        return err;
-}
-
 static char *get_name(char *name, char *p)
 {
         /* Extract <name> from nul-terminated p where p matches
@@ -550,7 +434,7 @@ static char *get_name(char *name, char *p)
  * old approach of multiple scanf occurrences with large numbers of
  * args. */
 
-/* static const char * const ss_fmt[] = { */
+/* static const char *const ss_fmt[] = { */
 /*      "%lln%llu%lu%lu%lu%lu%ln%ln%lln%llu%lu%lu%lu%lu%lu", */
 /*      "%llu%llu%lu%lu%lu%lu%ln%ln%llu%llu%lu%lu%lu%lu%lu", */
 /*      "%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu" */
@@ -558,13 +442,13 @@ static char *get_name(char *name, char *p)
 
         /* Lie about the size of the int pointed to for %n. */
 #if INT_MAX == LONG_MAX
-static const char * const ss_fmt[] = {
+static const char *const ss_fmt[] = {
         "%n%llu%u%u%u%u%n%n%n%llu%u%u%u%u%u",
         "%llu%llu%u%u%u%u%n%n%llu%llu%u%u%u%u%u",
         "%llu%llu%u%u%u%u%u%u%llu%llu%u%u%u%u%u%u"
 };
 #else
-static const char * const ss_fmt[] = {
+static const char *const ss_fmt[] = {
         "%n%llu%lu%lu%lu%lu%n%n%n%llu%lu%lu%lu%lu%lu",
         "%llu%llu%lu%lu%lu%lu%n%n%llu%llu%lu%lu%lu%lu%lu",
         "%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu"
@@ -615,6 +499,54 @@ static inline int procnetdev_version(char *buf)
         return 0;
 }
 
+/* Used only if "/proc/net/dev" isn't available */
+static int if_readconf(void)
+{
+        int numreqs = 30;
+        struct ifconf ifc;
+        struct ifreq *ifr;
+        int n, err = -1;
+        int skfd;
+
+        ifc.ifc_buf = NULL;
+
+        /* SIOCGIFCONF currently seems to only work properly on AF_INET sockets
+           (as of 2.1.128) */
+        skfd = socket(AF_INET, SOCK_DGRAM, 0);
+        if (skfd < 0) {
+                bb_perror_msg("error: no inet socket available");
+                return -1;
+        }
+
+        for (;;) {
+                ifc.ifc_len = sizeof(struct ifreq) * numreqs;
+                ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);
+
+                if (ioctl(skfd, SIOCGIFCONF, &ifc) < 0) {
+                        perror("SIOCGIFCONF");
+                        goto out;
+                }
+                if (ifc.ifc_len == sizeof(struct ifreq) * numreqs) {
+                        /* assume it overflowed and try again */
+                        numreqs += 10;
+                        continue;
+                }
+                break;
+        }
+
+        ifr = ifc.ifc_req;
+        for (n = 0; n < ifc.ifc_len; n += sizeof(struct ifreq)) {
+                add_interface(ifr->ifr_name);
+                ifr++;
+        }
+        err = 0;
+
+ out:
+        close(skfd);
+        free(ifc.ifc_buf);
+        return err;
+}
+
 static int if_readlist_proc(char *target)
 {
         static int proc_read;
@@ -660,11 +592,7 @@ static int if_readlist_proc(char *target)
 
 static int if_readlist(void)
 {
-        int err = if_readlist_proc(NULL);
-
-        if (!err)
-                err = if_readconf();
-        return err;
+        return if_readlist_proc(NULL);
 }
 
 static int for_all_interfaces(int (*doit) (struct interface *, void *),
@@ -687,81 +615,74 @@ static int for_all_interfaces(int (*doit) (struct interface *, void *),
 static int if_fetch(struct interface *ife)
 {
         struct ifreq ifr;
-        int fd;
         char *ifname = ife->name;
+        int skfd;
+
+        skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
 
         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-        if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0)
+        if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0) {
+                close(skfd);
                 return -1;
+        }
         ife->flags = ifr.ifr_flags;
 
         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-        if (ioctl(skfd, SIOCGIFHWADDR, &ifr) < 0)
-                memset(ife->hwaddr, 0, 32);
-        else
+        memset(ife->hwaddr, 0, 32);
+        if (ioctl(skfd, SIOCGIFHWADDR, &ifr) >= 0)
                 memcpy(ife->hwaddr, ifr.ifr_hwaddr.sa_data, 8);
 
         ife->type = ifr.ifr_hwaddr.sa_family;
 
         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-        if (ioctl(skfd, SIOCGIFMETRIC, &ifr) < 0)
-                ife->metric = 0;
-        else
+        ife->metric = 0;
+        if (ioctl(skfd, SIOCGIFMETRIC, &ifr) >= 0)
                 ife->metric = ifr.ifr_metric;
 
         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-        if (ioctl(skfd, SIOCGIFMTU, &ifr) < 0)
-                ife->mtu = 0;
-        else
+        ife->mtu = 0;
+        if (ioctl(skfd, SIOCGIFMTU, &ifr) >= 0)
                 ife->mtu = ifr.ifr_mtu;
 
+        memset(&ife->map, 0, sizeof(struct ifmap));
 #ifdef SIOCGIFMAP
         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
         if (ioctl(skfd, SIOCGIFMAP, &ifr) == 0)
                 ife->map = ifr.ifr_map;
-        else
 #endif
-                memset(&ife->map, 0, sizeof(struct ifmap));
 
 #ifdef HAVE_TXQUEUELEN
         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-        if (ioctl(skfd, SIOCGIFTXQLEN, &ifr) < 0)
-                ife->tx_queue_len = -1; /* unknown value */
-        else
+        ife->tx_queue_len = -1; /* unknown value */
+        if (ioctl(skfd, SIOCGIFTXQLEN, &ifr) >= 0)
                 ife->tx_queue_len = ifr.ifr_qlen;
 #else
         ife->tx_queue_len = -1; /* unknown value */
 #endif
 
-        /* IPv4 address? */
-        fd = get_socket_for_af(AF_INET);
-        if (fd >= 0) {
+        strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
+        ifr.ifr_addr.sa_family = AF_INET;
+        memset(&ife->addr, 0, sizeof(struct sockaddr));
+        if (ioctl(skfd, SIOCGIFADDR, &ifr) == 0) {
+                ife->has_ip = 1;
+                ife->addr = ifr.ifr_addr;
                 strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-                ifr.ifr_addr.sa_family = AF_INET;
-                if (ioctl(fd, SIOCGIFADDR, &ifr) == 0) {
-                        ife->has_ip = 1;
-                        ife->addr = ifr.ifr_addr;
-                        strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-                        if (ioctl(fd, SIOCGIFDSTADDR, &ifr) < 0)
-                                memset(&ife->dstaddr, 0, sizeof(struct sockaddr));
-                        else
-                                ife->dstaddr = ifr.ifr_dstaddr;
-
-                        strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-                        if (ioctl(fd, SIOCGIFBRDADDR, &ifr) < 0)
-                                memset(&ife->broadaddr, 0, sizeof(struct sockaddr));
-                        else
-                                ife->broadaddr = ifr.ifr_broadaddr;
-
-                        strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-                        if (ioctl(fd, SIOCGIFNETMASK, &ifr) < 0)
-                                memset(&ife->netmask, 0, sizeof(struct sockaddr));
-                        else
-                                ife->netmask = ifr.ifr_netmask;
-                } else
-                        memset(&ife->addr, 0, sizeof(struct sockaddr));
+                memset(&ife->dstaddr, 0, sizeof(struct sockaddr));
+                if (ioctl(skfd, SIOCGIFDSTADDR, &ifr) >= 0)
+                        ife->dstaddr = ifr.ifr_dstaddr;
+
+                strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
+                memset(&ife->broadaddr, 0, sizeof(struct sockaddr));
+                if (ioctl(skfd, SIOCGIFBRDADDR, &ifr) >= 0)
+                        ife->broadaddr = ifr.ifr_broadaddr;
+
+                strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
+                memset(&ife->netmask, 0, sizeof(struct sockaddr));
+                if (ioctl(skfd, SIOCGIFNETMASK, &ifr) >= 0)
+                        ife->netmask = ifr.ifr_netmask;
         }
 
+        close(skfd);
         return 0;
 }
 
@@ -887,7 +808,7 @@ static const struct hwtype ppp_hwtype = {
         .type =         ARPHRD_PPP
 };
 
-#ifdef CONFIG_FEATURE_IPV6
+#if ENABLE_FEATURE_IPV6
 static const struct hwtype sit_hwtype = {
         .name =                 "sit",
         .title =                "IPv6-in-IPv4",
@@ -897,19 +818,19 @@ static const struct hwtype sit_hwtype = {
 } ;
 #endif
 
-static const struct hwtype * const hwtypes[] = {
+static const struct hwtype *const hwtypes[] = {
         &loop_hwtype,
         &ether_hwtype,
         &ppp_hwtype,
         &unspec_hwtype,
-#ifdef CONFIG_FEATURE_IPV6
+#if ENABLE_FEATURE_IPV6
         &sit_hwtype,
 #endif
         NULL
 };
 
 #ifdef IFF_PORTSEL
-static const char * const if_port_text[] = {
+static const char *const if_port_text[] = {
         /* Keep in step with <linux/netdevice.h> */
         "unknown",
         "10base2",
@@ -925,7 +846,7 @@ static const char * const if_port_text[] = {
 /* Check our hardware type table for this type. */
 const struct hwtype *get_hwtype(const char *name)
 {
-        const struct hwtype * const *hwp;
+        const struct hwtype *const *hwp;
 
         hwp = hwtypes;
         while (*hwp != NULL) {
@@ -939,7 +860,7 @@ const struct hwtype *get_hwtype(const char *name)
 /* Check our hardware type table for this type. */
 const struct hwtype *get_hwntype(int type)
 {
-        const struct hwtype * const *hwp;
+        const struct hwtype *const *hwp;
 
         hwp = hwtypes;
         while (*hwp != NULL) {
@@ -987,7 +908,7 @@ static void print_bytes_scaled(unsigned long long ull, const char *end)
         printf("X bytes:%llu (%llu.%u %sB)%s", ull, int_part, frac_part, ext, end);
 }
 
-static const char * const ife_print_flags_strs[] = {
+static const char *const ife_print_flags_strs[] = {
         "UP ",
         "BROADCAST ",
         "DEBUG ",
@@ -1028,7 +949,7 @@ static const unsigned short ife_print_flags_mask[] = {
 
 static void ife_print(struct interface *ptr)
 {
-        struct aftype *ap;
+        const struct aftype *ap;
         const struct hwtype *hw;
         int hf;
         int can_compress = 0;
@@ -1265,15 +1186,7 @@ int display_interfaces(char *ifname)
 {
         int status;
 
-        /* Create a channel to the NET kernel. */
-        if ((skfd = sockets_open(0)) < 0) {
-                bb_perror_msg_and_die("socket");
-        }
-
-        /* Do we have to show the current setup? */
         status = if_print(ifname);
-#ifdef CONFIG_FEATURE_CLEAN_UP
-        sockets_close();
-#endif
-        exit(status < 0);
+
+        return (status < 0); /* status < 0 == 1 -- error */
 }