From nobody Wed Feb 12 14:07:43 2025 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4YtKrv2NPkz5mr7T; Wed, 12 Feb 2025 14:07:43 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4YtKrv1d2zz3wf2; Wed, 12 Feb 2025 14:07:43 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1739369263; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=TJINoFWBaMPkb2vm8aymBUYPAEDUKNzrhI9+1mXW6Nc=; b=KsTT8+IfmLboQMNciEX5EsEQ1K2fzgEQI1g1EJsq3PSNq+H989h79kW59gptaDytlvG2KF Eae92mXzgZzZRkKMGIdgc7jGz9/lk2fHXJzzVT4XQGPU6nnuPwieQL+v1V8wIzA8GUrOyD OUFofgrQ2unFoV1mAX3VzZvppMTxHy2KJng4pGvdxelXwO6Wo4XeqcK4S5UoiUM7SK+HdJ apvu86crNO4PGgTY0Ilpa42Y8xmeeve7loaMsP0aaImDjA9edAU9XkO5vTTtoaiRjwz2Ev EW4JQbNMZZzdmJxmKp8YvCnYOqH3B66prqklLKcNCMtxpyzXtyVbOuDD1C++Wg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1739369263; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=TJINoFWBaMPkb2vm8aymBUYPAEDUKNzrhI9+1mXW6Nc=; b=dRRbNs4rnGnu1AgeIeeroQYrv1IowD8x6Ef08eirj/cyU3+8I7AcAZFbdYmex8AtGaUeER YpSIBKrZ8wp99KvwtUts2wvHyX2GCXqJWTyP9Sy1jOvEM05mROOKIkjSU0W5npLgFyiX/o +8O6YPxzDQNjXUFtTuToeBKsON4U63m1iMgkjpR+PHKiFibJQjekeM1kMTIE4l+F48CROp LMOJA4t+2l2LPlraGeA9FzGkXnl+hPb7mqemuuGQd2ERAGnylcPpRHtmgZ8dxiZoXkKjJQ W8it55GgULfJAqEo3y3X5VFtQRFqWMDgo2vaATSk/qmg/zai5d/zyTT7UAEbdw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1739369263; a=rsa-sha256; cv=none; b=RMhntkSxVcacCNSM8UpSDPwaHTXRVVdf9BNSylg2TOTFaEkgBObmX7krUb81prKc7lg0TE YypTUQyv517ENSeff0XoOadgAv/TdKCRCeEVFOWVk4XXrwEPLWiMq9apnaJhOYU3jJ5QEH Qk4l3r1EFnPpIlBSU6T7LtlW1mjpN5zTABAmAoU8Wza+OV2fN8V1yKNe0HPz/MSAXd8bl5 09ghbBN/GQF3/0pHQN4GbBYmQHrU1USex3dB9LiN0sD2BZkQqt5H3wPgfBrEWPCEOJ7xnD T/P0FPXFEPuDwndJWssi/VhAO1vK3Nuy0ucQT9kMCop7DAy5pomITb38xptBzQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4YtKrv1669z12Wp; Wed, 12 Feb 2025 14:07:43 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 51CE7hE2043397; Wed, 12 Feb 2025 14:07:43 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 51CE7hv0043394; Wed, 12 Feb 2025 14:07:43 GMT (envelope-from git) Date: Wed, 12 Feb 2025 14:07:43 GMT Message-Id: <202502121407.51CE7hv0043394@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Michael Tuexen Subject: git: e1dd07ede923 - stable/13 - icmp: use per rate limit randomized jitter List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: tuexen X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: e1dd07ede92382bdcc52b3093e8f2ec5d9c88467 Auto-Submitted: auto-generated The branch stable/13 has been updated by tuexen: URL: https://cgit.FreeBSD.org/src/commit/?id=e1dd07ede92382bdcc52b3093e8f2ec5d9c88467 commit e1dd07ede92382bdcc52b3093e8f2ec5d9c88467 Author: Michael Tuexen AuthorDate: 2025-02-10 21:16:20 +0000 Commit: Michael Tuexen CommitDate: 2025-02-12 14:07:19 +0000 icmp: use per rate limit randomized jitter Using the same random jitter for multiple rate limits allows an attacker to use one rate limiter to figure out the current jitter and then use this knowledge to de-randomize the other rate limiters. This can be mitigated by using a separate randomized jitter for each rate limiter. This issue was reported as issue number 10 in Keyu Man et al.: SCAD: Towards a Universal and Automated Network Side-Channel Vulnerability Detection Reviewed by: rrs, Peter Lei, glebius MFC after: 3 days Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D48804 (cherry picked from commit 923c223f27e792e51ca13c476428adbbf6887551) --- sys/netinet/ip_icmp.c | 20 ++++++++++++-------- sys/netinet6/icmp6.c | 50 +++++++++++++++++++++++++++----------------------- 2 files changed, 39 insertions(+), 31 deletions(-) diff --git a/sys/netinet/ip_icmp.c b/sys/netinet/ip_icmp.c index f4b697f30eee..417a86672d6f 100644 --- a/sys/netinet/ip_icmp.c +++ b/sys/netinet/ip_icmp.c @@ -89,7 +89,7 @@ SYSCTL_PROC(_net_inet_icmp, ICMPCTL_ICMPLIM, icmplim, CTLTYPE_UINT | &sysctl_icmplim_and_jitter, "IU", "Maximum number of ICMP responses per second"); -VNET_DEFINE_STATIC(int, icmplim_curr_jitter) = 0; +VNET_DEFINE_STATIC(int, icmplim_curr_jitter[BANDLIM_MAX]) = {0}; #define V_icmplim_curr_jitter VNET(icmplim_curr_jitter) VNET_DEFINE_STATIC(u_int, icmplim_jitter) = 16; #define V_icmplim_jitter VNET(icmplim_jitter) @@ -1102,14 +1102,16 @@ static const char *icmp_rate_descrs[BANDLIM_MAX] = { }; static void -icmplim_new_jitter(void) +icmplim_new_jitter(int which) { /* * Adjust limit +/- to jitter the measurement to deny a side-channel * port scan as in https://dl.acm.org/doi/10.1145/3372297.3417280 */ + KASSERT(which >= 0 && which < BANDLIM_MAX, + ("%s: which %d", __func__, which)); if (V_icmplim_jitter > 0) - V_icmplim_curr_jitter = + V_icmplim_curr_jitter[which] = arc4random_uniform(V_icmplim_jitter * 2 + 1) - V_icmplim_jitter; } @@ -1138,7 +1140,9 @@ sysctl_icmplim_and_jitter(SYSCTL_HANDLER_ARGS) error = EINVAL; else { V_icmplim_jitter = new; - icmplim_new_jitter(); + for (int i = 0; i < BANDLIM_MAX; i++) { + icmplim_new_jitter(i); + } } } } @@ -1154,8 +1158,8 @@ icmp_bandlimit_init(void) for (int i = 0; i < BANDLIM_MAX; i++) { V_icmp_rates[i].cr_rate = counter_u64_alloc(M_WAITOK); V_icmp_rates[i].cr_ticks = ticks; + icmplim_new_jitter(i); } - icmplim_new_jitter(); } VNET_SYSINIT(icmp_bandlimit, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, icmp_bandlimit_init, NULL); @@ -1184,14 +1188,14 @@ badport_bandlim(int which) ("%s: which %d", __func__, which)); pps = counter_ratecheck(&V_icmp_rates[which], V_icmplim + - V_icmplim_curr_jitter); + V_icmplim_curr_jitter[which]); if (pps > 0) { if (V_icmplim_output) log(LOG_NOTICE, "Limiting %s response from %jd to %d packets/sec\n", icmp_rate_descrs[which], (intmax_t )pps, - V_icmplim + V_icmplim_curr_jitter); - icmplim_new_jitter(); + V_icmplim + V_icmplim_curr_jitter[which]); + icmplim_new_jitter(which); } if (pps == -1) return (-1); diff --git a/sys/netinet6/icmp6.c b/sys/netinet6/icmp6.c index 52430f9146ae..dd0044734c4b 100644 --- a/sys/netinet6/icmp6.c +++ b/sys/netinet6/icmp6.c @@ -2778,22 +2778,6 @@ SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ERRPPSLIMIT, errppslimit, &sysctl_icmp6lim_and_jitter, "IU", "Maximum number of ICMPv6 error/reply messages per second"); -VNET_DEFINE_STATIC(int, icmp6lim_curr_jitter) = 0; -#define V_icmp6lim_curr_jitter VNET(icmp6lim_curr_jitter) - -VNET_DEFINE_STATIC(u_int, icmp6lim_jitter) = 8; -#define V_icmp6lim_jitter VNET(icmp6lim_jitter) -SYSCTL_PROC(_net_inet6_icmp6, OID_AUTO, icmp6lim_jitter, CTLTYPE_UINT | - CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmp6lim_jitter), 0, - &sysctl_icmp6lim_and_jitter, "IU", - "Random errppslimit jitter adjustment limit"); - -VNET_DEFINE_STATIC(int, icmp6lim_output) = 1; -#define V_icmp6lim_output VNET(icmp6lim_output) -SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, icmp6lim_output, - CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmp6lim_output), 0, - "Enable logging of ICMPv6 response rate limiting"); - typedef enum { RATELIM_PARAM_PROB = 0, RATELIM_TOO_BIG, @@ -2815,15 +2799,33 @@ static const char *icmp6_rate_descrs[RATELIM_MAX] = { [RATELIM_OTHER] = "(other)", }; +VNET_DEFINE_STATIC(int, icmp6lim_curr_jitter[RATELIM_MAX]) = {0}; +#define V_icmp6lim_curr_jitter VNET(icmp6lim_curr_jitter) + +VNET_DEFINE_STATIC(u_int, icmp6lim_jitter) = 8; +#define V_icmp6lim_jitter VNET(icmp6lim_jitter) +SYSCTL_PROC(_net_inet6_icmp6, OID_AUTO, icmp6lim_jitter, CTLTYPE_UINT | + CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmp6lim_jitter), 0, + &sysctl_icmp6lim_and_jitter, "IU", + "Random errppslimit jitter adjustment limit"); + +VNET_DEFINE_STATIC(int, icmp6lim_output) = 1; +#define V_icmp6lim_output VNET(icmp6lim_output) +SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, icmp6lim_output, + CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmp6lim_output), 0, + "Enable logging of ICMPv6 response rate limiting"); + static void -icmp6lim_new_jitter(void) +icmp6lim_new_jitter(int which) { /* * Adjust limit +/- to jitter the measurement to deny a side-channel * port scan as in https://dl.acm.org/doi/10.1145/3372297.3417280 */ + KASSERT(which >= 0 && which < RATELIM_MAX, + ("%s: which %d", __func__, which)); if (V_icmp6lim_jitter > 0) - V_icmp6lim_curr_jitter = + V_icmp6lim_curr_jitter[which] = arc4random_uniform(V_icmp6lim_jitter * 2 + 1) - V_icmp6lim_jitter; } @@ -2852,7 +2854,9 @@ sysctl_icmp6lim_and_jitter(SYSCTL_HANDLER_ARGS) error = EINVAL; else { V_icmp6lim_jitter = new; - icmp6lim_new_jitter(); + for (int i = 0; i < RATELIM_MAX; i++) { + icmp6lim_new_jitter(i); + } } } } @@ -2872,8 +2876,8 @@ icmp6_ratelimit_init(void) for (int i = 0; i < RATELIM_MAX; i++) { V_icmp6_rates[i].cr_rate = counter_u64_alloc(M_WAITOK); V_icmp6_rates[i].cr_ticks = ticks; + icmp6lim_new_jitter(i); } - icmp6lim_new_jitter(); } VNET_SYSINIT(icmp6_ratelimit, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, icmp6_ratelimit_init, NULL); @@ -2935,14 +2939,14 @@ icmp6_ratelimit(const struct in6_addr *dst, const int type, const int code) }; pps = counter_ratecheck(&V_icmp6_rates[which], V_icmp6errppslim + - V_icmp6lim_curr_jitter); + V_icmp6lim_curr_jitter[which]); if (pps > 0) { if (V_icmp6lim_output) log(LOG_NOTICE, "Limiting ICMPv6 %s output from %jd " "to %d packets/sec\n", icmp6_rate_descrs[which], (intmax_t )pps, V_icmp6errppslim + - V_icmp6lim_curr_jitter); - icmp6lim_new_jitter(); + V_icmp6lim_curr_jitter[which]); + icmp6lim_new_jitter(which); } if (pps == -1) { ICMP6STAT_INC(icp6s_toofreq);