cmdline: check size of result buffer to avoid overflow

[libcmdline.git] / src / lib / cmdline_parse_etheraddr.c

diff --git a/src/lib/cmdline_parse_etheraddr.c b/src/lib/cmdline_parse_etheraddr.c
index 69df142..7a50e02 100644 (file)
--- a/src/lib/cmdline_parse_etheraddr.c
+++ b/src/lib/cmdline_parse_etheraddr.c
@@ -1,3 +1,37 @@
+/*-
+ * Copyright (c) <2010>, Intel Corporation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ *
+ * - Neither the name of Intel Corporation nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
 /*
  * Copyright (c) 2009, Olivier MATZ <zer0@droids-corp.org>
  * All rights reserved.
@@ -31,11 +65,7 @@
 #include <ctype.h>
 #include <string.h>
 #include <sys/types.h>
-#include <sys/socket.h>
 #include <net/ethernet.h>
-#ifdef __linux__
-#include <netinet/ether.h>
-#endif
 
 #include "cmdline_parse.h"
 #include "cmdline_parse_etheraddr.h"
@@ -50,27 +80,52 @@ struct cmdline_token_ops cmdline_token_etheraddr_ops = {
 
 #define ETHER_ADDRSTRLEN 18
 
-int 
-cmdline_parse_etheraddr(cmdline_parse_token_hdr_t *tk, const char *buf, void *res)
+#ifdef __linux__
+#define ea_oct ether_addr_octet
+#else
+#define ea_oct octet
+#endif
+
+static struct ether_addr *
+my_ether_aton(const char *a)
+{
+       int i;
+       static struct ether_addr ether_addr;
+       unsigned int o0, o1, o2, o3, o4, o5;
+
+       i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o0, &o1, &o2, &o3, &o4, &o5);
+
+       if (i != ETHER_ADDR_LEN)
+               return NULL;
+
+       ether_addr.ea_oct[0] = (uint8_t)o0;
+       ether_addr.ea_oct[1] = (uint8_t)o1;
+       ether_addr.ea_oct[2] = (uint8_t)o2;
+       ether_addr.ea_oct[3] = (uint8_t)o3;
+       ether_addr.ea_oct[4] = (uint8_t)o4;
+       ether_addr.ea_oct[5] = (uint8_t)o5;
+
+       return (struct ether_addr *)&ether_addr;
+}
+
+int
+cmdline_parse_etheraddr(__attribute__((unused)) cmdline_parse_token_hdr_t *tk,
+                       const char *buf, void *res, unsigned ressize)
 {
        unsigned int token_len = 0;
        char ether_str[ETHER_ADDRSTRLEN];
        struct ether_addr *etheraddr = res;
        struct ether_addr *tmp;
 
-       if (! *buf)
+       if (res && ressize < sizeof(struct ether_addr))
                return -1;
 
-       while (!cmdline_isendoftoken(buf[token_len]))
-               token_len++;
-                        
        /* if token is too big... */
-       if (token_len >= ETHER_ADDRSTRLEN)
+       token_len = snprintf(ether_str, sizeof(ether_str), "%s", buf);
+       if (token_len >= sizeof(ether_str))
                return -1;
 
-       snprintf(ether_str, token_len+1, "%s", buf);
-
-       tmp = ether_aton(ether_str);
+       tmp = my_ether_aton(ether_str);
        if (tmp == NULL)
                return -1;
 
@@ -78,8 +133,8 @@ cmdline_parse_etheraddr(cmdline_parse_token_hdr_t *tk, const char *buf, void *re
        return token_len;
 }
 
-int cmdline_get_help_etheraddr(cmdline_parse_token_hdr_t *tk, char *dstbuf,
-                           unsigned int size)
+int cmdline_get_help_etheraddr(__attribute__((unused)) cmdline_parse_token_hdr_t *tk,
+                              char *dstbuf, unsigned int size)
 {
        snprintf(dstbuf, size, "Ethernet address");
        return 0;