From 8d2a6935d842f12c25611b165eace778adb09a53 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Fri, 8 Nov 2019 13:20:34 +0800 Subject: [PATCH] sctp: add SCTP_EXPOSE_POTENTIALLY_FAILED_STATE sockopt This is a sockopt defined in section 7.3 of rfc7829: "Exposing the Potentially Failed Path State", by which users can change pf_expose per sock and asoc. The new sockopt SCTP_EXPOSE_POTENTIALLY_FAILED_STATE is also known as SCTP_EXPOSE_PF_STATE for short. v2->v3: - return -EINVAL if params.assoc_value > SCTP_PF_EXPOSE_MAX. - define SCTP_EXPOSE_PF_STATE SCTP_EXPOSE_POTENTIALLY_FAILED_STATE. v3->v4: - improve changelog. Signed-off-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller --- include/uapi/linux/sctp.h | 2 + net/sctp/socket.c | 79 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 81 insertions(+) diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h index d99b428ac34e..a190e4a7f546 100644 --- a/include/uapi/linux/sctp.h +++ b/include/uapi/linux/sctp.h @@ -137,6 +137,8 @@ typedef __s32 sctp_assoc_t; #define SCTP_ASCONF_SUPPORTED 128 #define SCTP_AUTH_SUPPORTED 129 #define SCTP_ECN_SUPPORTED 130 +#define SCTP_EXPOSE_POTENTIALLY_FAILED_STATE 131 +#define SCTP_EXPOSE_PF_STATE SCTP_EXPOSE_POTENTIALLY_FAILED_STATE /* PR-SCTP policies */ #define SCTP_PR_SCTP_NONE 0x0000 diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 318222e9c0a8..74c4e62ac741 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -4589,6 +4589,40 @@ out: return retval; } +static int sctp_setsockopt_pf_expose(struct sock *sk, + char __user *optval, + unsigned int optlen) +{ + struct sctp_assoc_value params; + struct sctp_association *asoc; + int retval = -EINVAL; + + if (optlen != sizeof(params)) + goto out; + + if (copy_from_user(¶ms, optval, optlen)) { + retval = -EFAULT; + goto out; + } + + if (params.assoc_value > SCTP_PF_EXPOSE_MAX) + goto out; + + asoc = sctp_id2assoc(sk, params.assoc_id); + if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC && + sctp_style(sk, UDP)) + goto out; + + if (asoc) + asoc->pf_expose = params.assoc_value; + else + sctp_sk(sk)->pf_expose = params.assoc_value; + retval = 0; + +out: + return retval; +} + /* API 6.2 setsockopt(), getsockopt() * * Applications use setsockopt() and getsockopt() to set or retrieve @@ -4798,6 +4832,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname, case SCTP_ECN_SUPPORTED: retval = sctp_setsockopt_ecn_supported(sk, optval, optlen); break; + case SCTP_EXPOSE_POTENTIALLY_FAILED_STATE: + retval = sctp_setsockopt_pf_expose(sk, optval, optlen); + break; default: retval = -ENOPROTOOPT; break; @@ -7909,6 +7946,45 @@ out: return retval; } +static int sctp_getsockopt_pf_expose(struct sock *sk, int len, + char __user *optval, + int __user *optlen) +{ + struct sctp_assoc_value params; + struct sctp_association *asoc; + int retval = -EFAULT; + + if (len < sizeof(params)) { + retval = -EINVAL; + goto out; + } + + len = sizeof(params); + if (copy_from_user(¶ms, optval, len)) + goto out; + + asoc = sctp_id2assoc(sk, params.assoc_id); + if (!asoc && params.assoc_id != SCTP_FUTURE_ASSOC && + sctp_style(sk, UDP)) { + retval = -EINVAL; + goto out; + } + + params.assoc_value = asoc ? asoc->pf_expose + : sctp_sk(sk)->pf_expose; + + if (put_user(len, optlen)) + goto out; + + if (copy_to_user(optval, ¶ms, len)) + goto out; + + retval = 0; + +out: + return retval; +} + static int sctp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { @@ -8121,6 +8197,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname, case SCTP_ECN_SUPPORTED: retval = sctp_getsockopt_ecn_supported(sk, len, optval, optlen); break; + case SCTP_EXPOSE_POTENTIALLY_FAILED_STATE: + retval = sctp_getsockopt_pf_expose(sk, len, optval, optlen); + break; default: retval = -ENOPROTOOPT; break; -- 2.39.5