From: Chris Packham chris.packham@alliedtelesis.co.nz
Previously values greater than 255 were implicitly truncated. Add some stricter checking to reject addresses with components >255.
With the input "1234192.168.1.1" the old behaviour would truncate the address to 192.168.1.1. New behaviour rejects the string outright and returns 0, which for the purposes of IP addresses can be considered an error.
Signed-off-by: Chris Packham chris.packham@alliedtelesis.co.nz
--- Changes in v3: -Fix a what should have been a glaringly obvious omission that cause all addresses to be interpreted as 0. Made even stricter so that v6 addresses that start with numbers aren't accepted.
Changes in v2: None
lib/net_utils.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/lib/net_utils.c b/lib/net_utils.c index b425a68..afe0c16 100644 --- a/lib/net_utils.c +++ b/lib/net_utils.c @@ -38,12 +38,17 @@ IPaddr_t string_to_ip(const char *s) return(0);
for (addr=0, i=0; i<4; ++i) { - ulong val = s ? simple_strtoul(s, &e, 10) : 0; + ulong val = simple_strtoul(s, &e, 10); + if (val > 255) + return 0; addr <<= 8; - addr |= (val & 0xFF); - if (s) { - s = (*e) ? e+1 : e; - } + addr |= val; + if (*e == '.') + s = e+1; + else if (*e == '\0') + break; + else + return 0; }
return (htonl(addr));