diff options
| -rw-r--r-- | dhcp.c | 22 |
1 files changed, 13 insertions, 9 deletions
@@ -49,7 +49,7 @@ struct opt { uint8_t c[255]; }; -static struct opt opts[255]; +static struct opt opts[256]; #define DHCPDISCOVER 1 #define DHCPOFFER 2 @@ -363,25 +363,29 @@ int dhcp(const struct ctx *c, struct iov_tail *data) for (i = 0; i < ARRAY_SIZE(opts); i++) opts[i].clen = -1; - opt_len = iov_tail_size(data); - while (opt_len >= 2) { + while ((opt_len = iov_tail_size(data))) { uint8_t olen_storage, type_storage; const uint8_t *olen; uint8_t *type; - type = IOV_REMOVE_HEADER(data, type_storage); - olen = IOV_REMOVE_HEADER(data, olen_storage); - if (!type || !olen) + if (!(type = IOV_REMOVE_HEADER(data, type_storage))) return -1; - opt_len = iov_tail_size(data); - if (opt_len < *olen) + if (*type == 255) + break; + + if (*type == 0) /* Pad Option (RFC 2132, 3.1): one byte */ + continue; + + if (!(olen = IOV_REMOVE_HEADER(data, olen_storage))) + return -1; + + if (opt_len - 2 < *olen) return -1; iov_to_buf(&data->iov[0], data->cnt, data->off, &opts[*type].c, *olen); opts[*type].clen = *olen; iov_drop_header(data, *olen); - opt_len -= *olen; } opts[80].slen = -1; |