diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 4e90e6ae79df..986593685566 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -109,6 +109,7 @@ enum { #define TCP_REPAIR 19 /* TCP sock is under repair right now */ #define TCP_REPAIR_QUEUE 20 #define TCP_QUEUE_SEQ 21 +#define TCP_REPAIR_OPTIONS 22 enum { TCP_NO_QUEUE, diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index b4e690ddb08c..3ce3bd031f33 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2218,6 +2218,68 @@ static inline int tcp_can_repair_sock(struct sock *sk) ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_ESTABLISHED)); } +static int tcp_repair_options_est(struct tcp_sock *tp, char __user *optbuf, unsigned int len) +{ + /* + * Options are stored in CODE:VALUE form where CODE is 8bit and VALUE + * fits the respective TCPOLEN_ size + */ + + while (len > 0) { + u8 opcode; + + if (get_user(opcode, optbuf)) + return -EFAULT; + + optbuf++; + len--; + + switch (opcode) { + case TCPOPT_MSS: { + u16 in_mss; + + if (len < sizeof(in_mss)) + return -ENODATA; + if (get_user(in_mss, optbuf)) + return -EFAULT; + + tp->rx_opt.mss_clamp = in_mss; + + optbuf += sizeof(in_mss); + len -= sizeof(in_mss); + break; + } + case TCPOPT_WINDOW: { + u8 wscale; + + if (len < sizeof(wscale)) + return -ENODATA; + if (get_user(wscale, optbuf)) + return -EFAULT; + + if (wscale > 14) + return -EFBIG; + + tp->rx_opt.snd_wscale = wscale; + + optbuf += sizeof(wscale); + len -= sizeof(wscale); + break; + } + case TCPOPT_SACK_PERM: + tp->rx_opt.sack_ok |= TCP_SACK_SEEN; + if (sysctl_tcp_fack) + tcp_enable_fack(tp); + break; + case TCPOPT_TIMESTAMP: + tp->rx_opt.tstamp_ok = 1; + break; + } + } + + return 0; +} + /* * Socket option code for TCP. */ @@ -2426,6 +2488,15 @@ static int do_tcp_setsockopt(struct sock *sk, int level, err = -EINVAL; break; + case TCP_REPAIR_OPTIONS: + if (!tp->repair) + err = -EINVAL; + else if (sk->sk_state == TCP_ESTABLISHED) + err = tcp_repair_options_est(tp, optval, optlen); + else + err = -EPERM; + break; + case TCP_CORK: /* When set indicates to always queue non-full frames. * Later the user clears this option and we transmit