start_stop_daemon: NOMMU fixes, round 2 by Alex Landau <landau_alex@yahoo.com>
[oweals/busybox.git] / networking / ifupdown.c
index ff4f7855b151c20c079d5f40b0ecdcdd48722191..040bbe38965cbee39050ac3a3df736aae0475d5b 100644 (file)
  *  Changes to upstream version
  *  Remove checks for kernel version, assume kernel version 2.2.0 or better.
  *  Lines in the interfaces file cannot wrap.
- *  To adhere to the FHS, the default state file is /var/run/ifstate.
+ *  To adhere to the FHS, the default state file is /var/run/ifstate
+ *  (defined via CONFIG_IFUPDOWN_IFSTATE_PATH) and can be overridden by build
+ *  configuration.
  *
  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  */
 
-#include "busybox.h"
 #include <sys/utsname.h>
 #include <fnmatch.h>
 #include <getopt.h>
 
+#include "libbb.h"
+
 #define MAX_OPT_DEPTH 10
 #define EUNBALBRACK 10001
 #define EUNDEFVAR   10002
@@ -103,31 +106,6 @@ static const char *startup_PATH;
 
 #if ENABLE_FEATURE_IFUPDOWN_IPV4 || ENABLE_FEATURE_IFUPDOWN_IPV6
 
-#if ENABLE_FEATURE_IFUPDOWN_IP
-
-static unsigned count_bits(unsigned a)
-{
-       unsigned result;
-       result = (a & 0x55) + ((a >> 1) & 0x55);
-       result = (result & 0x33) + ((result >> 2) & 0x33);
-       return (result & 0x0F) + ((result >> 4) & 0x0F);
-}
-
-static int count_netmask_bits(char *dotted_quad)
-{
-       unsigned result, a, b, c, d;
-       /* Found a netmask...  Check if it is dotted quad */
-       if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
-               return -1;
-       // FIXME: will be confused by e.g. 255.0.255.0
-       result = count_bits(a);
-       result += count_bits(b);
-       result += count_bits(c);
-       result += count_bits(d);
-       return (int)result;
-}
-#endif
-
 static void addstr(char **bufp, const char *str, size_t str_length)
 {
        /* xasprintf trick will be smaller, but we are often
@@ -176,6 +154,39 @@ static char *get_var(const char *id, size_t idlen, struct interface_defn_t *ifd)
        return NULL;
 }
 
+#if ENABLE_FEATURE_IFUPDOWN_IP
+static int count_netmask_bits(const char *dotted_quad)
+{
+//     int result;
+//     unsigned a, b, c, d;
+//     /* Found a netmask...  Check if it is dotted quad */
+//     if (sscanf(dotted_quad, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
+//             return -1;
+//     if ((a|b|c|d) >> 8)
+//             return -1; /* one of numbers is >= 256 */
+//     d |= (a << 24) | (b << 16) | (c << 8); /* IP */
+//     d = ~d; /* 11110000 -> 00001111 */
+
+       /* Shorter version */
+       int result;
+       struct in_addr ip;
+       unsigned d;
+
+       if (inet_aton(dotted_quad, &ip) == 0)
+               return -1; /* malformed dotted IP */
+       d = ntohl(ip.s_addr); /* IP in host order */
+       d = ~d; /* 11110000 -> 00001111 */
+       if (d & (d+1)) /* check that it is in 00001111 form */
+               return -1; /* no it is not */
+       result = 32;
+       while (d) {
+               d >>= 1;
+               result--;
+       }
+       return result;
+}
+#endif
+
 static char *parse(const char *command, struct interface_defn_t *ifd)
 {
        size_t old_pos[MAX_OPT_DEPTH] = { 0 };
@@ -245,11 +256,14 @@ static char *parse(const char *command, struct interface_defn_t *ifd)
                                        if (strncmp(command, "bnmask", 6) == 0) {
                                                unsigned res;
                                                varvalue = get_var("netmask", 7, ifd);
-                                               if (varvalue && (res = count_netmask_bits(varvalue)) > 0) {
-                                                       const char *argument = utoa(res);
-                                                       addstr(&result, argument, strlen(argument));
-                                                       command = nextpercent + 1;
-                                                       break;
+                                               if (varvalue) {
+                                                       res = count_netmask_bits(varvalue);
+                                                       if (res > 0) {
+                                                               const char *argument = utoa(res);
+                                                               addstr(&result, argument, strlen(argument));
+                                                               command = nextpercent + 1;
+                                                               break;
+                                                       }
                                                }
                                        }
 #endif
@@ -374,7 +388,7 @@ static const struct method_t methods6[] = {
 
 static const struct address_family_t addr_inet6 = {
        "inet6",
-       sizeof(methods6) / sizeof(struct method_t),
+       ARRAY_SIZE(methods6),
        methods6
 };
 #endif /* FEATURE_IFUPDOWN_IPV6 */
@@ -439,7 +453,7 @@ static int static_down(struct interface_defn_t *ifd, execfn *exec)
        return ((result == 2) ? 2 : 0);
 }
 
-#if !ENABLE_APP_UDHCPC
+#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
 struct dhcp_client_t
 {
        const char *name;
@@ -448,55 +462,69 @@ struct dhcp_client_t
 };
 
 static const struct dhcp_client_t ext_dhcp_clients[] = {
-       { "udhcpc",
-               "udhcpc -R -n -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
-               "kill -TERM `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
-       },
-       { "pump",
-               "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
-               "pump -i %iface% -k",
+       { "dhcpcd",
+               "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %clientid%]][[ -l %leasetime%]] %iface%",
+               "dhcpcd -k %iface%",
        },
        { "dhclient",
                "dhclient -pf /var/run/dhclient.%iface%.pid %iface%",
                "kill -9 `cat /var/run/dhclient.%iface%.pid` 2>/dev/null",
        },
-       { "dhcpcd",
-               "dhcpcd[[ -h %hostname%]][[ -i %vendor%]][[ -I %clientid%]][[ -l %leasetime%]] %iface%",
-               "dhcpcd -k %iface%",
+       { "pump",
+               "pump -i %iface%[[ -h %hostname%]][[ -l %leasehours%]]",
+               "pump -i %iface% -k",
+       },
+       { "udhcpc",
+               "udhcpc -R -n -p /var/run/udhcpc.%iface%.pid -i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
+               "kill `cat /var/run/udhcpc.%iface%.pid` 2>/dev/null",
        },
 };
-#endif
+#endif /* ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCPC */
 
 static int dhcp_up(struct interface_defn_t *ifd, execfn *exec)
 {
-#if ENABLE_APP_UDHCPC
-       return execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid "
-                       "-i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
-                       ifd, exec);
-#else
-       int i, nclients = sizeof(ext_dhcp_clients) / sizeof(ext_dhcp_clients[0]);
-       for (i = 0; i < nclients; i++) {
+#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
+#if ENABLE_FEATURE_IFUPDOWN_IP
+       /* ip doesn't up iface when it configures it (unlike ifconfig) */
+       if (!execute("ip link set %iface% up", ifd, exec))
+               return 0;
+#endif
+       int i;
+       for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
                if (exists_execable(ext_dhcp_clients[i].name))
                        return execute(ext_dhcp_clients[i].startcmd, ifd, exec);
        }
        bb_error_msg("no dhcp clients found");
        return 0;
+#elif ENABLE_APP_UDHCPC
+#if ENABLE_FEATURE_IFUPDOWN_IP
+       /* ip doesn't up iface when it configures it (unlike ifconfig) */
+       if (!execute("ip link set %iface% up", ifd, exec))
+               return 0;
+#endif
+       return execute("udhcpc -R -n -p /var/run/udhcpc.%iface%.pid "
+                       "-i %iface%[[ -H %hostname%]][[ -c %clientid%]][[ -s %script%]]",
+                       ifd, exec);
+#else
+       return 0; /* no dhcp support */
 #endif
 }
 
 static int dhcp_down(struct interface_defn_t *ifd, execfn *exec)
 {
-#if ENABLE_APP_UDHCPC
-       return execute("kill -TERM "
-                      "`cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
-#else
-       int i, nclients = sizeof(ext_dhcp_clients) / sizeof(ext_dhcp_clients[0]);
-       for (i = 0; i < nclients; i++) {
+#if ENABLE_FEATURE_IFUPDOWN_EXTERNAL_DHCP
+       int i;
+       for (i = 0; i < ARRAY_SIZE(ext_dhcp_clients); i++) {
                if (exists_execable(ext_dhcp_clients[i].name))
                        return execute(ext_dhcp_clients[i].stopcmd, ifd, exec);
        }
        bb_error_msg("no dhcp clients found, using static interface shutdown");
        return static_down(ifd, exec);
+#elif ENABLE_APP_UDHCPC
+       return execute("kill "
+                      "`cat /var/run/udhcpc.%iface%.pid` 2>/dev/null", ifd, exec);
+#else
+       return 0; /* no dhcp support */
 #endif
 }
 
@@ -508,8 +536,8 @@ static int manual_up_down(struct interface_defn_t *ifd, execfn *exec)
 static int bootp_up(struct interface_defn_t *ifd, execfn *exec)
 {
        return execute("bootpc[[ --bootfile %bootfile%]] --dev %iface%"
-                       "[[ --server %server%]][[ --hwaddr %hwaddr%]] "
-                       "--returniffail --serverbcast", ifd, exec);
+                       "[[ --server %server%]][[ --hwaddr %hwaddr%]]"
+                       " --returniffail --serverbcast", ifd, exec);
 }
 
 static int ppp_up(struct interface_defn_t *ifd, execfn *exec)
@@ -546,7 +574,7 @@ static const struct method_t methods[] = {
 
 static const struct address_family_t addr_inet = {
        "inet",
-       sizeof(methods) / sizeof(struct method_t),
+       ARRAY_SIZE(methods),
        methods
 };
 
@@ -829,7 +857,8 @@ static struct interfaces_file_t *read_interfaces(const char *filename)
                free(buf);
        }
        if (ferror(f) != 0) {
-               bb_perror_msg_and_die("%s", filename);
+               /* ferror does NOT set errno! */
+               bb_error_msg_and_die("%s: I/O error", filename);
        }
        fclose(f);
 
@@ -879,9 +908,10 @@ static void set_environ(struct interface_defn_t *iface, const char *mode)
 
        for (i = 0; i < iface->n_options; i++) {
                if (strcmp(iface->option[i].name, "up") == 0
-                               || strcmp(iface->option[i].name, "down") == 0
-                               || strcmp(iface->option[i].name, "pre-up") == 0
-                               || strcmp(iface->option[i].name, "post-down") == 0) {
+                || strcmp(iface->option[i].name, "down") == 0
+                || strcmp(iface->option[i].name, "pre-up") == 0
+                || strcmp(iface->option[i].name, "post-down") == 0
+               ) {
                        continue;
                }
                *(environend++) = setlocalenv("IF_%s=%s", iface->option[i].name, iface->option[i].value);
@@ -1074,8 +1104,8 @@ static llist_t *find_iface_state(llist_t *state_list, const char *iface)
        llist_t *search = state_list;
 
        while (search) {
-               if ((strncmp(search->data, iface, iface_len) == 0) &&
-                               (search->data[iface_len] == '=')) {
+               if ((strncmp(search->data, iface, iface_len) == 0)
+                && (search->data[iface_len] == '=')) {
                        return search;
                }
                search = search->link;
@@ -1087,7 +1117,7 @@ static llist_t *find_iface_state(llist_t *state_list, const char *iface)
 static llist_t *read_iface_state(void)
 {
        llist_t *state_list = NULL;
-       FILE *state_fp = fopen("/var/run/ifstate", "r");
+       FILE *state_fp = fopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "r");
 
        if (state_fp) {
                char *start, *end_ptr;
@@ -1235,8 +1265,10 @@ int ifupdown_main(int argc, char **argv)
                if (!okay && !FORCE) {
                        bb_error_msg("ignoring unknown interface %s", liface);
                        any_failures = 1;
-               } else {
+               } else if (!NO_ACT) {
                        /* update the state file */
+                       FILE *state_fp;
+                       llist_t *state;
                        llist_t *state_list = read_iface_state();
                        llist_t *iface_state = find_iface_state(state_list, iface);
 
@@ -1255,17 +1287,15 @@ int ifupdown_main(int argc, char **argv)
                        }
 
                        /* Actually write the new state */
-                       if (!NO_ACT) {
-                               FILE *state_fp = xfopen("/var/run/ifstate", "w");
-                               llist_t *state = state_list;
-                               while (state) {
-                                       if (state->data) {
-                                               fprintf(state_fp, "%s\n", state->data);
-                                       }
-                                       state = state->link;
+                       state_fp = xfopen(CONFIG_IFUPDOWN_IFSTATE_PATH, "w");
+                       state = state_list;
+                       while (state) {
+                               if (state->data) {
+                                       fprintf(state_fp, "%s\n", state->data);
                                }
-                               fclose(state_fp);
+                               state = state->link;
                        }
+                       fclose(state_fp);
                        llist_free(state_list, free);
                }
        }