udhcp: new config option "Rewrite the lease file at every new acknowledge"

       (Mats Erik Andersson <mats@blue2net.com> (Blue2Net AB))
udhcp: consistently treat server_config.start/end IPs as host-order
       fix IP parsing for 64bit machines
       fix unsafe hton macro usage in read_opt()
       do not chdir("/") when daemonizing
       fix help text

10 files changed, 151 insertions, 115 deletions

diff --git a/include/usage.h b/include/usage.h
index 6d02c8bbf..68325046f 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -3575,7 +3575,8 @@ USE_FEATURE_RUN_PARTS_FANCY("\n	-l	Prints names of all matching files even when
        "Adjust filesystem options on ext[23] filesystems"
 
 #define udhcpc_trivial_usage \
-       "[-Cfbnqtv] [-c CID] [-V VCLS] [-H HOSTNAME] [-i INTERFACE]\n[-p pidfile] [-r IP] [-s script]"
+       "[-Cfbnqtv] [-c CID] [-V VCLS] [-H HOSTNAME] [-i INTERFACE]\n" \
+       "        [-p pidfile] [-r IP] [-s script]"
 #define udhcpc_full_usage \
        "        -V,--vendorclass=CLASSID        Set vendor class identifier\n" \
        "        -i,--interface=INTERFACE        Interface to use (default: eth0)\n" \
@@ -3594,7 +3595,7 @@ USE_FEATURE_RUN_PARTS_FANCY("\n	-l	Prints names of all matching files even when
        "        -v,--version    Display version" \
 
 #define udhcpd_trivial_usage \
-       "[configfile]\n" \
+       "[configfile]" \
 
 #define udhcpd_full_usage \
        ""
diff --git a/networking/udhcp/Config.in b/networking/udhcp/Config.in
index 9dd02c497..7a3eda9cc 100644
--- a/networking/udhcp/Config.in
+++ b/networking/udhcp/Config.in
@@ -32,6 +32,16 @@ config APP_DUMPLEASES
 
           See http://udhcp.busybox.net for further details.
 
+config FEATURE_UDHCPD_WRITE_LEASES_EARLY
+        bool "Rewrite the lease file at every new acknowledge"
+        default n
+        depends on APP_UDHCPD
+        help
+          If selected, udhcpd will write a new file with leases every
+          time a new lease has been accepted, thus eleminating the need
+          to send SIGUSR1 for the initial writing, or updating. Any timed
+          rewriting remains undisturbed
+
 config APP_UDHCPC
         bool "udhcp Client (udhcpc)"
         default n
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 06806ec66..50ac31e61 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -114,8 +114,7 @@ static void client_background(void)
  * If that will be properly disabled for NOMMU, client_background()
  * will work on NOMMU too */
 #else
-// chdir(/) is problematic. Imagine that e.g. pidfile name is RELATIVE! what will unlink do then, eh?
-        bb_daemonize(DAEMON_CHDIR_ROOT);
+        bb_daemonize(0);
         /* rewrite pidfile, as our pid is different now */
         if (client_config.pidfile)
                 write_pidfile(client_config.pidfile);
diff --git a/networking/udhcp/dhcpc.h b/networking/udhcp/dhcpc.h
index fa091bf72..09b014239 100644
--- a/networking/udhcp/dhcpc.h
+++ b/networking/udhcp/dhcpc.h
@@ -17,12 +17,12 @@ struct client_config_t {
         /* (can be set directly to the result of getopt32) */
         char foreground;                /* Do not fork */
         char quit_after_lease;          /* Quit after obtaining lease */
-        char release_on_quit;           /* perform release on quit */
+        char release_on_quit;           /* Perform release on quit */
         char abort_if_no_lease;         /* Abort if no lease */
         char background_if_no_lease;    /* Fork to background if no lease */
-        const char *interface;                /* The name of the interface to use */
+        const char *interface;          /* The name of the interface to use */
         char *pidfile;                  /* Optionally store the process ID */
-        const char *script;                   /* User script to run at dhcp events */
+        const char *script;             /* User script to run at dhcp events */
         uint8_t *clientid;              /* Optional client id to use */
         uint8_t *vendorclass;           /* Optional vendor class-id to use */
         uint8_t *hostname;              /* Optional hostname to use */
diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index 778121b61..6be3c0e2e 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -37,7 +37,7 @@ int udhcpd_main(int argc, char **argv)
 //Huh, dhcpd don't have --foreground, --syslog options?? TODO
 
         if (!ENABLE_FEATURE_UDHCP_DEBUG) {
-                bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
+                bb_daemonize_or_rexec(0, argv);
                 logmode &= ~LOGMODE_STDIO;
         }
 
@@ -60,15 +60,15 @@ int udhcpd_main(int argc, char **argv)
         }
 
         /* Sanity check */
-        num_ips = ntohl(server_config.end) - ntohl(server_config.start) + 1;
+        num_ips = server_config.end_ip - server_config.start_ip + 1;
         if (server_config.max_leases > num_ips) {
-                bb_error_msg("max_leases value (%lu) not sane, "
-                        "setting to %lu instead",
+                bb_error_msg("max_leases=%lu is too big, "
+                        "setting to %lu",
                         server_config.max_leases, num_ips);
                 server_config.max_leases = num_ips;
         }
 
-        leases = xzalloc(server_config.max_leases * sizeof(struct dhcpOfferedAddr));
+        leases = xzalloc(server_config.max_leases * sizeof(*leases));
         read_leases(server_config.lease_file);
 
         if (read_interface(server_config.interface, &server_config.ifindex,
@@ -207,10 +207,13 @@ int udhcpd_main(int argc, char **argv)
                                         /* make some contention for this address */
                                         } else
                                                 sendNAK(&packet);
-                                } else if (requested_align < server_config.start
-                                        || requested_align > server_config.end
-                                ) {
-                                        sendNAK(&packet);
+                                } else {
+                                        uint32_t r = ntohl(requested_align);
+                                        if (r < server_config.start_ip
+                                         || r > server_config.end_ip
+                                        ) {
+                                                sendNAK(&packet);
+                                        }
                                 } /* else remain silent */
 
                         } else {
diff --git a/networking/udhcp/dhcpd.h b/networking/udhcp/dhcpd.h
index 7c4fe695a..05e3cf004 100644
--- a/networking/udhcp/dhcpd.h
+++ b/networking/udhcp/dhcpd.h
@@ -27,23 +27,24 @@ struct static_lease {
 
 struct server_config_t {
         uint32_t server;                /* Our IP, in network order */
-        uint32_t start;                 /* Start address of leases, network order */
-        uint32_t end;                   /* End of leases, network order */
+        /* start,end are in host order: we need to compare start <= ip <= end */
+        uint32_t start_ip;              /* Start address of leases, in host order */
+        uint32_t end_ip;                /* End of leases, in host order */
         struct option_set *options;     /* List of DHCP options loaded from the config file */
         char *interface;                /* The name of the interface to use */
         int ifindex;                    /* Index number of the interface to use */
         uint8_t arp[6];                 /* Our arp address */
-        unsigned long lease;            /* lease time in seconds (host order) */
-        unsigned long max_leases;       /* maximum number of leases (including reserved address) */
         char remaining;                 /* should the lease file be interpreted as lease time remaining, or
                                          * as the time the lease expires */
+        unsigned long lease;            /* lease time in seconds (host order) */
+        unsigned long max_leases;       /* maximum number of leases (including reserved address) */
         unsigned long auto_time;        /* how long should udhcpd wait before writing a config file.
                                          * if this is zero, it will only write one on SIGUSR1 */
         unsigned long decline_time;     /* how long an address is reserved if a client returns a
                                          * decline message */
         unsigned long conflict_time;    /* how long an arp conflict offender is leased for */
         unsigned long offer_time;       /* how long an offered address is reserved */
-        unsigned long min_lease;        /* minimum lease a client can request*/
+        unsigned long min_lease;        /* minimum lease a client can request */
         char *lease_file;
         char *pidfile;
         char *notify_file;              /* What to run whenever leases are written */
@@ -95,13 +96,6 @@ int send_inform(struct dhcpMessage *oldpacket);
 
 /*** files.h ***/
 
-struct config_keyword {
-        const char *keyword;
-        int (* const handler)(const char *line, void *var);
-        void *var;
-        const char *def;
-};
-
 int read_config(const char *file);
 void write_leases(void);
 void read_leases(const char *file);
diff --git a/networking/udhcp/files.c b/networking/udhcp/files.c
index 41c8717cd..7fc734889 100644
--- a/networking/udhcp/files.c
+++ b/networking/udhcp/files.c
@@ -11,42 +11,30 @@
 #include "options.h"
 
 
-/*
- * Domain names may have 254 chars, and string options can be 254
- * chars long. However, 80 bytes will be enough for most, and won't
- * hog up memory. If you have a special application, change it
- */
-#define READ_CONFIG_BUF_SIZE 80
-
-/* on these functions, make sure you datatype matches */
+/* on these functions, make sure your datatype matches */
 static int read_ip(const char *line, void *arg)
 {
         len_and_sockaddr *lsa;
-        int retval = 0;
 
         lsa = host_and_af2sockaddr(line, 0, AF_INET);
         if (lsa) {
-                *(struct in_addr*)arg = lsa->sin.sin_addr;
+                *(uint32_t*)arg = lsa->sin.sin_addr.s_addr;
                 free(lsa);
-                retval = 1;
+                return 1;
         }
-        return retval;
+        return 0;
 }
 
 static int read_mac(const char *line, void *arg)
 {
         uint8_t *mac_bytes = arg;
         struct ether_addr *temp_ether_addr;
-        int retval = 1;
 
         temp_ether_addr = ether_aton(line);
-
         if (temp_ether_addr == NULL)
-                retval = 0;
-        else
-                memcpy(mac_bytes, temp_ether_addr, 6);
-
-        return retval;
+                return 0;
+        memcpy(mac_bytes, temp_ether_addr, 6);
+        return 1;
 }
 
 
@@ -56,14 +44,13 @@ static int read_str(const char *line, void *arg)
 
         free(*dest);
         *dest = xstrdup(line);
-
         return 1;
 }
 
 
 static int read_u32(const char *line, void *arg)
 {
-        *((uint32_t*)arg) = bb_strtou32(line, NULL, 10);
+        *(uint32_t*)arg = bb_strtou32(line, NULL, 10);
         return errno == 0;
 }
 
@@ -71,15 +58,16 @@ static int read_u32(const char *line, void *arg)
 static int read_yn(const char *line, void *arg)
 {
         char *dest = arg;
-        int retval = 1;
 
-        if (!strcasecmp("yes", line))
+        if (!strcasecmp("yes", line)) {
                 *dest = 1;
-        else if (!strcasecmp("no", line))
+                return 1;
+        }
+        if (!strcasecmp("no", line)) {
                 *dest = 0;
-        else retval = 0;
-
-        return retval;
+                return 1;
+        }
+        return 0;
 }
 
 
@@ -89,8 +77,9 @@ struct option_set *find_option(struct option_set *opt_list, char code)
         while (opt_list && opt_list->data[OPT_CODE] < code)
                 opt_list = opt_list->next;
 
-        if (opt_list && opt_list->data[OPT_CODE] == code) return opt_list;
-        else return NULL;
+        if (opt_list && opt_list->data[OPT_CODE] == code)
+                return opt_list;
+        return NULL;
 }
 
 
@@ -111,7 +100,7 @@ static void attach_option(struct option_set **opt_list,
 #endif
 
                 /* make a new option */
-                new = xmalloc(sizeof(struct option_set));
+                new = xmalloc(sizeof(*new));
                 new->data = xmalloc(length + 2);
                 new->data[OPT_CODE] = option->code;
                 new->data[OPT_LEN] = length;
@@ -184,7 +173,7 @@ static int read_opt(const char *const_line, void *arg)
                         return 0;
                 if (!strcasecmp(option->name, opt))
                         break;
-                 option++;
+                option++;
         }
 
         do {
@@ -199,8 +188,11 @@ static int read_opt(const char *const_line, void *arg)
                         break;
                 case OPTION_IP_PAIR:
                         retval = read_ip(val, buffer);
-                        if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
-                        if (retval) retval = read_ip(val, buffer + 4);
+                        val = strtok(NULL, ", \t/-");
+                        if (!val)
+                                retval = 0;
+                        if (retval)
+                                retval = read_ip(val, buffer + 4);
                         break;
                 case OPTION_STRING:
 #if ENABLE_FEATURE_RFC3397
@@ -220,22 +212,33 @@ static int read_opt(const char *const_line, void *arg)
                         buffer[0] = strtoul(val, &endptr, 0);
                         retval = (endptr[0] == '\0');
                         break;
-                case OPTION_U16:
-                        *result_u16 = htons(strtoul(val, &endptr, 0));
-                        retval = (endptr[0] == '\0');
+                /* htonX are macros in older libc's, using temp var
+                 * in code below for safety */
+                /* TODO: use bb_strtoX? */
+                case OPTION_U16: {
+                        unsigned long tmp = strtoul(val, &endptr, 0);
+                        *result_u16 = htons(tmp);
+                        retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/);
                         break;
-                case OPTION_S16:
-                        *result_u16 = htons(strtol(val, &endptr, 0));
+                }
+                case OPTION_S16: {
+                        long tmp = strtol(val, &endptr, 0);
+                        *result_u16 = htons(tmp);
                         retval = (endptr[0] == '\0');
                         break;
-                case OPTION_U32:
-                        *result_u32 = htonl(strtoul(val, &endptr, 0));
+                }
+                case OPTION_U32: {
+                        unsigned long tmp = strtoul(val, &endptr, 0);
+                        *result_u32 = htonl(tmp);
                         retval = (endptr[0] == '\0');
                         break;
-                case OPTION_S32:
-                        *result_u32 = htonl(strtol(val, &endptr, 0));
+                }
+                case OPTION_S32: {
+                        long tmp = strtol(val, &endptr, 0);
+                        *result_u32 = htonl(tmp);
                         retval = (endptr[0] == '\0');
                         break;
+                }
                 default:
                         break;
                 }
@@ -253,7 +256,6 @@ static int read_staticlease(const char *const_line, void *arg)
         uint8_t *mac_bytes;
         uint32_t *ip;
 
-
         /* Allocate memory for addresses */
         mac_bytes = xmalloc(sizeof(unsigned char) * 8);
         ip = xmalloc(sizeof(uint32_t));
@@ -275,39 +277,54 @@ static int read_staticlease(const char *const_line, void *arg)
 }
 
 
+struct config_keyword {
+        const char *keyword;
+        int (*handler)(const char *line, void *var);
+        void *var;
+        const char *def;
+};
+
 static const struct config_keyword keywords[] = {
-        /* keyword      handler   variable address              default */
-        {"start",       read_ip,  &(server_config.start),       "192.168.0.20"},
-        {"end",         read_ip,  &(server_config.end),         "192.168.0.254"},
-        {"interface",   read_str, &(server_config.interface),   "eth0"},
-        {"option",      read_opt, &(server_config.options),     ""},
-        {"opt",         read_opt, &(server_config.options),     ""},
-        {"max_leases",  read_u32, &(server_config.max_leases),  "254"},
-        {"remaining",   read_yn,  &(server_config.remaining),   "yes"},
-        {"auto_time",   read_u32, &(server_config.auto_time),   "7200"},
-        {"decline_time",read_u32, &(server_config.decline_time),"3600"},
-        {"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
-        {"offer_time",  read_u32, &(server_config.offer_time),  "60"},
-        {"min_lease",   read_u32, &(server_config.min_lease),   "60"},
-        {"lease_file",  read_str, &(server_config.lease_file),  LEASES_FILE},
-        {"pidfile",     read_str, &(server_config.pidfile),     "/var/run/udhcpd.pid"},
-        {"notify_file", read_str, &(server_config.notify_file), ""},
-        {"siaddr",      read_ip,  &(server_config.siaddr),      "0.0.0.0"},
-        {"sname",       read_str, &(server_config.sname),       ""},
-        {"boot_file",   read_str, &(server_config.boot_file),   ""},
-        {"static_lease",read_staticlease, &(server_config.static_leases),       ""},
-        /*ADDME: static lease */
-        {"",            NULL,     NULL,                         ""}
+        /* keyword       handler   variable address               default */
+        {"start",        read_ip,  &(server_config.start_ip),     "192.168.0.20"},
+        {"end",          read_ip,  &(server_config.end_ip),       "192.168.0.254"},
+        {"interface",    read_str, &(server_config.interface),    "eth0"},
+        {"option",       read_opt, &(server_config.options),      ""},
+        {"opt",          read_opt, &(server_config.options),      ""},
+        /* Avoid "max_leases value not sane" warning by setting default
+         * to default_end_ip - default_start_ip + 1: */
+        {"max_leases",   read_u32, &(server_config.max_leases),   "235"},
+        {"remaining",    read_yn,  &(server_config.remaining),    "yes"},
+        {"auto_time",    read_u32, &(server_config.auto_time),    "7200"},
+        {"decline_time", read_u32, &(server_config.decline_time), "3600"},
+        {"conflict_time",read_u32, &(server_config.conflict_time),"3600"},
+        {"offer_time",   read_u32, &(server_config.offer_time),   "60"},
+        {"min_lease",    read_u32, &(server_config.min_lease),    "60"},
+        {"lease_file",   read_str, &(server_config.lease_file),   LEASES_FILE},
+        {"pidfile",      read_str, &(server_config.pidfile),      "/var/run/udhcpd.pid"},
+        {"notify_file",  read_str, &(server_config.notify_file),  ""},
+        {"siaddr",       read_ip,  &(server_config.siaddr),       "0.0.0.0"},
+        {"sname",        read_str, &(server_config.sname),        ""},
+        {"boot_file",    read_str, &(server_config.boot_file),    ""},
+        {"static_lease", read_staticlease, &(server_config.static_leases), ""},
+        /* ADDME: static lease */
 };
 
 
+/*
+ * Domain names may have 254 chars, and string options can be 254
+ * chars long. However, 80 bytes will be enough for most, and won't
+ * hog up memory. If you have a special application, change it
+ */
+#define READ_CONFIG_BUF_SIZE 80
+
 int read_config(const char *file)
 {
         FILE *in;
         char buffer[READ_CONFIG_BUF_SIZE], *token, *line;
         int i, lm = 0;
 
-        for (i = 0; keywords[i].keyword[0]; i++)
+        for (i = 0; i < ARRAY_SIZE(keywords); i++)
                 if (keywords[i].def[0])
                         keywords[i].handler(keywords[i].def, keywords[i].var);
 
@@ -337,7 +354,7 @@ int read_config(const char *file)
                 while (i >= 0 && isspace(line[i]))
                         line[i--] = '\0';
 
-                for (i = 0; keywords[i].keyword[0]; i++)
+                for (i = 0; i < ARRAY_SIZE(keywords); i++)
                         if (!strcasecmp(token, keywords[i].keyword))
                                 if (!keywords[i].handler(line, keywords[i].var)) {
                                         bb_error_msg("cannot parse line %d of %s", lm, file);
@@ -348,6 +365,10 @@ int read_config(const char *file)
                                 }
         }
         fclose(in);
+
+        server_config.start_ip = ntohl(server_config.start_ip);
+        server_config.end_ip = ntohl(server_config.end_ip);
+
         return 1;
 }
 
@@ -408,9 +429,11 @@ void read_leases(const char *file)
          && full_read(fp, &lease, sizeof(lease)) == sizeof(lease)
         ) {
                 /* ADDME: is it a static lease */
-                if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
+                uint32_t y = ntohl(lease.yiaddr);
+                if (y >= server_config.start_ip && y <= server_config.end_ip) {
                         lease.expires = ntohl(lease.expires);
-                        if (!server_config.remaining) lease.expires -= time(0);
+                        if (!server_config.remaining)
+                                lease.expires -= time(0);
                         if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
                                 bb_error_msg("too many leases while loading %s", file);
                                 break;
diff --git a/networking/udhcp/leases.c b/networking/udhcp/leases.c
index 5d8775f63..ceec07345 100644
--- a/networking/udhcp/leases.c
+++ b/networking/udhcp/leases.c
@@ -119,8 +119,8 @@ uint32_t find_address(int check_expired)
         uint32_t addr, ret;
         struct dhcpOfferedAddr *lease = NULL;
 
-        addr = ntohl(server_config.start); /* addr is in host order here */
-        for (;addr <= ntohl(server_config.end); addr++) {
+        addr = server_config.start_ip; /* addr is in host order here */
+        for (;addr <= server_config.end_ip; addr++) {
 
                 /* ie, 192.168.55.0 */
                 if (!(addr & 0xFF)) continue;
diff --git a/networking/udhcp/serverpacket.c b/networking/udhcp/serverpacket.c
index e1a88addd..ecbf50a14 100644
--- a/networking/udhcp/serverpacket.c
+++ b/networking/udhcp/serverpacket.c
@@ -122,19 +122,18 @@ int sendOffer(struct dhcpMessage *oldpacket)
                         if (!lease_expired(lease))
                                 lease_time_align = lease->expires - time(0);
                         packet.yiaddr = lease->yiaddr;
-
                 /* Or the client has a requested ip */
                 } else if ((req = get_option(oldpacket, DHCP_REQUESTED_IP))
-                        /* Don't look here (ugly hackish thing to do) */
-                        && memcpy(&req_align, req, 4)
-                        /* and the ip is in the lease range */
-                        && ntohl(req_align) >= ntohl(server_config.start)
-                        && ntohl(req_align) <= ntohl(server_config.end)
-                        && !static_lease_ip /* Check that its not a static lease */
-                        /* and is not already taken/offered */
-                        && (!(lease = find_lease_by_yiaddr(req_align))
-                                /* or its taken, but expired */ /* ADDME: or maybe in here */
-                                || lease_expired(lease))
+                 /* Don't look here (ugly hackish thing to do) */
+                 && memcpy(&req_align, req, 4)
+                 /* and the ip is in the lease range */
+                 && ntohl(req_align) >= server_config.start_ip
+                 && ntohl(req_align) <= server_config.end_ip
+                 && !static_lease_ip /* Check that its not a static lease */
+                 /* and is not already taken/offered */
+                 && (!(lease = find_lease_by_yiaddr(req_align))
+                        /* or its taken, but expired */ /* ADDME: or maybe in here */
+                        || lease_expired(lease))
                 ) {
                         packet.yiaddr = req_align; /* FIXME: oh my, is there a host using this IP? */
                         /* otherwise, find a free IP */
@@ -142,7 +141,8 @@ int sendOffer(struct dhcpMessage *oldpacket)
                         /* Is it a static lease? (No, because find_address skips static lease) */
                         packet.yiaddr = find_address(0);
                         /* try for an expired lease */
-                        if (!packet.yiaddr) packet.yiaddr = find_address(1);
+                        if (!packet.yiaddr)
+                                packet.yiaddr = find_address(1);
                 }
 
                 if (!packet.yiaddr) {
@@ -209,7 +209,8 @@ int sendACK(struct dhcpMessage *oldpacket, uint32_t yiaddr)
         init_packet(&packet, oldpacket, DHCPACK);
         packet.yiaddr = yiaddr;
 
-        if ((lease_time = get_option(oldpacket, DHCP_LEASE_TIME))) {
+        lease_time = get_option(oldpacket, DHCP_LEASE_TIME);
+        if (lease_time) {
                 memcpy(&lease_time_align, lease_time, 4);
                 lease_time_align = ntohl(lease_time_align);
                 if (lease_time_align > server_config.lease)
@@ -236,6 +237,10 @@ int sendACK(struct dhcpMessage *oldpacket, uint32_t yiaddr)
                 return -1;
 
         add_lease(packet.chaddr, packet.yiaddr, lease_time_align);
+        if (ENABLE_FEATURE_UDHCPD_WRITE_LEASES_EARLY) {
+                /* rewrite the file with leases at every new acceptance */
+                write_leases();
+        }
 
         return 0;
 }
diff --git a/networking/udhcp/socket.c b/networking/udhcp/socket.c
index d294fb259..be5985f88 100644
--- a/networking/udhcp/socket.c
+++ b/networking/udhcp/socket.c
@@ -43,7 +43,7 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
         struct ifreq ifr;
         struct sockaddr_in *our_ip;
 
-        memset(&ifr, 0, sizeof(struct ifreq));
+        memset(&ifr, 0, sizeof(ifr));
         fd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
         if (fd < 0) {
                 bb_perror_msg("socket failed");
@@ -54,7 +54,8 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
         strncpy(ifr.ifr_name, interface, sizeof(ifr.ifr_name));
         if (addr) {
                 if (ioctl(fd, SIOCGIFADDR, &ifr) != 0) {
-                        bb_perror_msg("SIOCGIFADDR failed, is the interface up and configured?");
+                        bb_perror_msg("SIOCGIFADDR failed (is interface %s "
+                                        "up and configured?)", interface);
                         close(fd);
                         return -1;
                 }
@@ -117,7 +118,7 @@ int listen_socket(uint32_t ip, int port, const char *inf)
                 return -1;
         }
 
-        if (bind(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) == -1) {
+        if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
                 close(fd);
                 return -1;
         }