diff options
-rw-r--r-- | src/ipcalc.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/src/ipcalc.c b/src/ipcalc.c index 9108e4c2..2efb339f 100644 --- a/src/ipcalc.c +++ b/src/ipcalc.c @@ -107,6 +107,8 @@ int mask2prefix(struct in_addr mask) uint32_t saddr = ntohl(mask.s_addr); for (count=0; saddr > 0; count++) { + if (!((1 << 31) & saddr)) + return -1; saddr=saddr << 1; } @@ -339,6 +341,11 @@ int main(int argc, const char **argv) { return 1; } prefix = mask2prefix(netmask); + if (prefix < 0 ) { + if (!beSilent) + fprintf(stderr, "ipcalc: bad netmask: %s\n", netmaskStr); + return 1; + } } } |