diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 42 |
1 files changed, 30 insertions, 12 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index c1ce304ba8d2..24f1630b2afb 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3603,6 +3603,23 @@ old_ack: return 0; } +static void tcp_parse_fastopen_option(int len, const unsigned char *cookie, + bool syn, struct tcp_fastopen_cookie *foc, + bool exp_opt) +{ + /* Valid only in SYN or SYN-ACK with an even length. */ + if (!foc || !syn || len < 0 || (len & 1)) + return; + + if (len >= TCP_FASTOPEN_COOKIE_MIN && + len <= TCP_FASTOPEN_COOKIE_MAX) + memcpy(foc->val, cookie, len); + else if (len != 0) + len = -1; + foc->len = len; + foc->exp = exp_opt; +} + /* Look for tcp options. Normally only called on SYN and SYNACK packets. * But, this can also be called on packets in the established flow when * the fast version below fails. @@ -3692,21 +3709,22 @@ void tcp_parse_options(const struct sk_buff *skb, */ break; #endif + case TCPOPT_FASTOPEN: + tcp_parse_fastopen_option( + opsize - TCPOLEN_FASTOPEN_BASE, + ptr, th->syn, foc, false); + break; + case TCPOPT_EXP: /* Fast Open option shares code 254 using a - * 16 bits magic number. It's valid only in - * SYN or SYN-ACK with an even size. + * 16 bits magic number. */ - if (opsize < TCPOLEN_EXP_FASTOPEN_BASE || - get_unaligned_be16(ptr) != TCPOPT_FASTOPEN_MAGIC || - !foc || !th->syn || (opsize & 1)) - break; - foc->len = opsize - TCPOLEN_EXP_FASTOPEN_BASE; - if (foc->len >= TCP_FASTOPEN_COOKIE_MIN && - foc->len <= TCP_FASTOPEN_COOKIE_MAX) - memcpy(foc->val, ptr + 2, foc->len); - else if (foc->len != 0) - foc->len = -1; + if (opsize >= TCPOLEN_EXP_FASTOPEN_BASE && + get_unaligned_be16(ptr) == + TCPOPT_FASTOPEN_MAGIC) + tcp_parse_fastopen_option(opsize - + TCPOLEN_EXP_FASTOPEN_BASE, + ptr + 2, th->syn, foc, true); break; } |