From 7f2527e5a7f513b9f415643ddc0ecd236b596887 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Wed, 14 Mar 2007 22:11:20 +0000 Subject: arp, networking/interface.c: eliminate statics and unneeded on-stack buffers, disable (comment out) some apparently unused (and buggy) code paths. -700 bytes. --- networking/arp.c | 132 +++++++++++++++++++++++++++---------------------------- 1 file changed, 65 insertions(+), 67 deletions(-) (limited to 'networking/arp.c') diff --git a/networking/arp.c b/networking/arp.c index 2af6bc970..7a36f44bb 100644 --- a/networking/arp.c +++ b/networking/arp.c @@ -27,8 +27,6 @@ #define DFLT_AF "inet" #define DFLT_HW "ether" -#define _PATH_PROCNET_ARP "/proc/net/arp" - #define ARP_OPT_A (0x1) #define ARP_OPT_p (0x2) #define ARP_OPT_H (0x4) @@ -64,7 +62,7 @@ static const char *const options[] = { /* Called only from main, once */ static int arp_del(char **args) { - char host[128]; + char *host; struct arpreq req; struct sockaddr sa; int flags = 0; @@ -73,8 +71,8 @@ static int arp_del(char **args) memset(&req, 0, sizeof(req)); /* Resolve the host name. */ - safe_strncpy(host, *args, 128); - if (ap->input(0, host, &sa) < 0) { + host = *args; + if (ap->input(host, &sa) < 0) { bb_herror_msg_and_die("%s", host); } @@ -130,8 +128,8 @@ static int arp_del(char **args) if (*++args == NULL) bb_show_usage(); if (strcmp(*args, "255.255.255.255") != 0) { - safe_strncpy(host, *args, 128); - if (ap->input(0, host, &sa) < 0) { + host = *args; + if (ap->input(host, &sa) < 0) { bb_herror_msg_and_die("%s", host); } memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr)); @@ -213,15 +211,15 @@ static void arp_getdevhw(char *ifname, struct sockaddr *sa, /* Called only from main, once */ static int arp_set(char **args) { - char host[128]; + char *host; struct arpreq req; struct sockaddr sa; int flags; memset(&req, 0, sizeof(req)); - safe_strncpy(host, *args++, 128); - if (ap->input(0, host, &sa) < 0) { + host = *args++; + if (ap->input(host, &sa) < 0) { bb_herror_msg_and_die("%s", host); } /* If a host has more than one address, use the correct one! */ @@ -285,8 +283,8 @@ static int arp_set(char **args) if (*++args == NULL) bb_show_usage(); if (strcmp(*args, "255.255.255.255") != 0) { - safe_strncpy(host, *args++, 128); - if (ap->input(0, host, &sa) < 0) { + host = *args; + if (ap->input(host, &sa) < 0) { bb_herror_msg_and_die("%s", host); } memcpy(&req.arp_netmask, &sa, sizeof(struct sockaddr)); @@ -362,82 +360,82 @@ arp_disp(const char *name, char *ip, int type, int arp_flags, /* Called only from main, once */ static int arp_show(char *name) { - char host[100]; + const char *host; + const char *hostname; + FILE *fp; struct sockaddr sa; - char ip[100]; - char hwa[100]; - char mask[100]; - char line[200]; - char dev[100]; int type, flags; - FILE *fp; - const char *hostname; int num; unsigned entries = 0, shown = 0; + char ip[128]; + char hwa[128]; + char mask[128]; + char line[128]; + char dev[128]; - host[0] = '\0'; - + host = NULL; if (name != NULL) { /* Resolve the host name. */ - safe_strncpy(host, name, (sizeof host)); - if (ap->input(0, host, &sa) < 0) { - bb_herror_msg_and_die("%s", host); + if (ap->input(name, &sa) < 0) { + bb_herror_msg_and_die("%s", name); } - safe_strncpy(host, ap->sprint(&sa, 1), sizeof(host)); + host = xstrdup(ap->sprint(&sa, 1)); } - /* Open the PROCps kernel table. */ - fp = xfopen(_PATH_PROCNET_ARP, "r"); - /* Bypass header -- read until newline */ - if (fgets(line, sizeof(line), fp) != (char *) NULL) { + fp = xfopen("/proc/net/arp", "r"); + /* Bypass header -- read one line */ + fgets(line, sizeof(line), fp); + + /* Read the ARP cache entries. */ + while (fgets(line, sizeof(line), fp)) { + mask[0] = '-'; mask[1] = '\0'; dev[0] = '-'; dev[1] = '\0'; - /* Read the ARP cache entries. */ - for (; fgets(line, sizeof(line), fp);) { - num = sscanf(line, "%s 0x%x 0x%x %100s %100s %100s\n", - ip, &type, &flags, hwa, mask, dev); - if (num < 4) - break; - - entries++; - /* if the user specified hw-type differs, skip it */ - if (hw_set && (type != hw->type)) - continue; - - /* if the user specified address differs, skip it */ - if (host[0] && strcmp(ip, host) != 0) - continue; - - /* if the user specified device differs, skip it */ - if (device[0] && strcmp(dev, device) != 0) - continue; - - shown++; - /* This IS ugly but it works -be */ - if (option_mask32 & ARP_OPT_n) - hostname = "?"; - else { - if (ap->input(0, ip, &sa) < 0) - hostname = ip; - else - hostname = ap->sprint(&sa, (option_mask32 & ARP_OPT_n) | 0x8000); - if (strcmp(hostname, ip) == 0) - hostname = "?"; - } + /* All these strings can't overflow + * because fgets above reads limited amount of data */ + num = sscanf(line, "%s 0x%x 0x%x %s %s %s\n", + ip, &type, &flags, hwa, mask, dev); + if (num < 4) + break; - arp_disp(hostname, ip, type, flags, hwa, mask, dev); + entries++; + /* if the user specified hw-type differs, skip it */ + if (hw_set && (type != hw->type)) + continue; + + /* if the user specified address differs, skip it */ + if (host && strcmp(ip, host) != 0) + continue; + + /* if the user specified device differs, skip it */ + if (device[0] && strcmp(dev, device) != 0) + continue; + + shown++; + /* This IS ugly but it works -be */ + hostname = "?"; + if (!(option_mask32 & ARP_OPT_n)) { + if (ap->input(ip, &sa) < 0) + hostname = ip; + else + hostname = ap->sprint(&sa, (option_mask32 & ARP_OPT_n) | 0x8000); + if (strcmp(hostname, ip) == 0) + hostname = "?"; } + + arp_disp(hostname, ip, type, flags, hwa, mask, dev); } if (option_mask32 & ARP_OPT_v) printf("Entries: %d\tSkipped: %d\tFound: %d\n", entries, entries - shown, shown); if (!shown) { - if (hw_set || host[0] || device[0]) + if (hw_set || host || device[0]) printf("No match found in %d entries\n", entries); } - - fclose(fp); - + if (ENABLE_FEATURE_CLEAN_UP) { + free((char*)host); + fclose(fp); + } return 0; } -- cgit v1.2.3