fix __ipparse to parse the generic numbers-and-dots IPv4 format correctly

* allow at most 4 parts
* bounds check the parts correctly
* disallow leading whitespace and sign
* check the address family before falling back to IPv6

diff --git a/src/network/__ipparse.c b/src/network/__ipparse.c
index b0647aa..2480265 100644 (file)
--- a/src/network/__ipparse.c
+++ b/src/network/__ipparse.c
@@ -1,27 +1,31 @@
 #include <string.h>
 #include <stdlib.h>
+#include <ctype.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include "__dns.h"
-#include <stdio.h>
 
 int __ipparse(void *dest, int family, const char *s0)
 {
        const char *s = s0;
        unsigned char *d = dest;
        unsigned long a[16] = { 0 };
-       const char *z;
+       char *z;
        int i;
 
        if (family == AF_INET6) goto not_v4;
 
        for (i=0; i<4; i++) {
-               a[i] = strtoul(s, (char **)&z, 0);
-               if (z==s || (*z && *z != '.')) goto not_v4;
+               a[i] = strtoul(s, &z, 0);
+               if (z==s || (*z && *z != '.') || !isdigit(*s)) {
+                       if (family == AF_INET) return -1;
+                       goto not_v4;
+               }
                if (!*z) break;
                s=z+1;
        }
+       if (i==4) return -1;
        switch (i) {
        case 0:
                a[1] = a[0] & 0xffffff;
@@ -35,7 +39,10 @@ int __ipparse(void *dest, int family, const char *s0)
        }
        ((struct sockaddr_in *)d)->sin_family = AF_INET;
        d = (void *)&((struct sockaddr_in *)d)->sin_addr;
-       for (i=0; i<4; i++) d[i] = a[i];
+       for (i=0; i<4; i++) {
+               if (a[i] > 255) return -1;
+               d[i] = a[i];
+       }
        return 0;
 
 not_v4: