udhcp: handle errors in read_staticlease

also gets rid of ether-aton's static buffer in ether-wake:
   text   data    bss    dec    hexfilename
 838664    441   7572 846677  ceb55busybox_old
 838650    441   7564 846655  ceb3fbusybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 13 insertions, 15 deletions

diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h
index 2179c53..15fe785 100644
--- a/networking/udhcp/common.h
+++ b/networking/udhcp/common.h
@@ -176,7 +176,7 @@ uint8_t *dname_enc(const uint8_t *cstr, int clen, const char *src, int *retlen)
 
 // RFC 2131  Table 5: Fields and options used by DHCP clients
 //
-// Fiels 'hops', 'yiaddr', 'siaddr', 'giaddr' are always zero
+// Fields 'hops', 'yiaddr', 'siaddr', 'giaddr' are always zero
 //
 // Field      DHCPDISCOVER          DHCPINFORM            DHCPREQUEST           DHCPDECLINE         DHCPRELEASE
 // -----      ------------          ------------          -----------           -----------         -----------
diff --git a/networking/udhcp/files.c b/networking/udhcp/files.c
index 968d8ed..05a7b99 100644
--- a/networking/udhcp/files.c
+++ b/networking/udhcp/files.c
@@ -34,11 +34,6 @@ static int FAST_FUNC read_nip(const char *line, void *arg)
 	return 1;
 }
 
-static int FAST_FUNC read_mac(const char *line, void *arg)
-{
-	return NULL == ether_aton_r(line, (struct ether_addr *)arg);
-}
-
 static int FAST_FUNC read_str(const char *line, void *arg)
 {
 	char **dest = arg;
@@ -242,6 +237,7 @@ static int FAST_FUNC read_opt(const char *const_line, void *arg)
 		if (retval)
 			attach_option(opt_list, option, opt, length);
 	} while (retval && option->flags & OPTION_LIST);
+
 	return retval;
 }
 
@@ -250,19 +246,21 @@ static int FAST_FUNC read_staticlease(const char *const_line, void *arg)
 	char *line;
 	char *mac_string;
 	char *ip_string;
-	struct ether_addr mac_bytes;
-	uint32_t ip;
+	struct ether_addr mac_bytes; /* it's "struct { uint8_t mac[6]; }" */
+	uint32_t nip;
 
 	/* Read mac */
 	line = (char *) const_line;
 	mac_string = strtok_r(line, " \t", &line);
-	read_mac(mac_string, &mac_bytes);
+	if (!mac_string || !ether_aton_r(mac_string, &mac_bytes))
+		return 0;
 
 	/* Read ip */
 	ip_string = strtok_r(NULL, " \t", &line);
-	read_nip(ip_string, &ip);
+	if (!ip_string || !read_nip(ip_string, &nip))
+		return 0;
 
-	add_static_lease(arg, (uint8_t*) &mac_bytes, ip);
+	add_static_lease(arg, (uint8_t*) &mac_bytes, nip);
 
 	log_static_leases(arg);
 
@@ -316,7 +314,7 @@ void FAST_FUNC read_config(const char *file)
 	parser = config_open(file);
 	while (config_read(parser, token, 2, 2, "# \t", PARSE_NORMAL)) {
 		for (k = keywords, i = 0; i < ARRAY_SIZE(keywords); k++, i++) {
-			if (!strcasecmp(token[0], k->keyword)) {
+			if (strcasecmp(token[0], k->keyword) == 0) {
 				if (!k->handler(token[1], k->var)) {
 					bb_error_msg("can't parse line %u in %s",
 							parser->lineno, file);
diff --git a/networking/udhcp/packet.c b/networking/udhcp/packet.c
index 03d5e1f..5b113bc 100644
--- a/networking/udhcp/packet.c
+++ b/networking/udhcp/packet.c
@@ -113,8 +113,8 @@ int FAST_FUNC udhcp_recv_kernel_packet(struct dhcp_packet *packet, int fd)
 			};
 			int i;
 			for (i = 0; broken_vendors[i][0]; i++) {
-				if (vendor[OPT_LEN - 2] == (uint8_t)strlen(broken_vendors[i])
-				 && !strncmp((char*)vendor, broken_vendors[i], vendor[OPT_LEN - 2])
+				if (vendor[OPT_LEN - OPT_DATA] == (uint8_t)strlen(broken_vendors[i])
+				 && strncmp((char*)vendor, broken_vendors[i], vendor[OPT_LEN - OPT_DATA]) == 0
 				) {
 					log1("Broken client (%s), forcing broadcast replies",
 						broken_vendors[i]);
@@ -122,7 +122,7 @@ int FAST_FUNC udhcp_recv_kernel_packet(struct dhcp_packet *packet, int fd)
 				}
 			}
 #else
-			if (vendor[OPT_LEN - 2] == (uint8_t)(sizeof("MSFT 98")-1)
+			if (vendor[OPT_LEN - OPT_DATA] == (uint8_t)(sizeof("MSFT 98")-1)
 			 && memcmp(vendor, "MSFT 98", sizeof("MSFT 98")-1) == 0
 			) {
 				log1("Broken client (%s), forcing broadcast replies", "MSFT 98");