From a08595b2219e6fbd848f07d9bb63c8922c5d97c0 Mon Sep 17 00:00:00 2001 From: Lukasz Pawelczyk Date: Mon, 10 Jun 2019 12:58:56 +0200 Subject: extensions: libxt_owner: Add supplementary groups option The --suppl-groups option causes GIDs specified with --gid-owner to be also checked in the supplementary groups of a process. Signed-off-by: Lukasz Pawelczyk Signed-off-by: Pablo Neira Ayuso --- extensions/libxt_owner.c | 24 +++++++++++++++++------- extensions/libxt_owner.man | 4 ++++ extensions/libxt_owner.t | 4 ++++ 3 files changed, 25 insertions(+), 7 deletions(-) (limited to 'extensions') diff --git a/extensions/libxt_owner.c b/extensions/libxt_owner.c index 87e4df31..1702b478 100644 --- a/extensions/libxt_owner.c +++ b/extensions/libxt_owner.c @@ -56,6 +56,7 @@ enum { O_PROCESS, O_SESSION, O_COMM, + O_SUPPL_GROUPS, }; static void owner_mt_help_v0(void) @@ -87,7 +88,8 @@ static void owner_mt_help(void) "owner match options:\n" "[!] --uid-owner userid[-userid] Match local UID\n" "[!] --gid-owner groupid[-groupid] Match local GID\n" -"[!] --socket-exists Match if socket exists\n"); +"[!] --socket-exists Match if socket exists\n" +" --suppl-groups Also match supplementary groups set with --gid-owner\n"); } #define s struct ipt_owner_info @@ -131,6 +133,7 @@ static const struct xt_option_entry owner_mt_opts[] = { .flags = XTOPT_INVERT}, {.name = "socket-exists", .id = O_SOCK_EXISTS, .type = XTTYPE_NONE, .flags = XTOPT_INVERT}, + {.name = "suppl-groups", .id = O_SUPPL_GROUPS, .type = XTTYPE_NONE}, XTOPT_TABLEEND, }; @@ -275,6 +278,11 @@ static void owner_mt_parse(struct xt_option_call *cb) info->invert |= XT_OWNER_SOCKET; info->match |= XT_OWNER_SOCKET; break; + case O_SUPPL_GROUPS: + if (!(info->match & XT_OWNER_GID)) + xtables_param_act(XTF_BAD_VALUE, "owner", "--suppl-groups", "you need to use --gid-owner first"); + info->match |= XT_OWNER_SUPPL_GROUPS; + break; } } @@ -455,9 +463,10 @@ static void owner_mt_print(const void *ip, const struct xt_entry_match *match, { const struct xt_owner_match_info *info = (void *)match->data; - owner_mt_print_item(info, "owner socket exists", XT_OWNER_SOCKET, numeric); - owner_mt_print_item(info, "owner UID match", XT_OWNER_UID, numeric); - owner_mt_print_item(info, "owner GID match", XT_OWNER_GID, numeric); + owner_mt_print_item(info, "owner socket exists", XT_OWNER_SOCKET, numeric); + owner_mt_print_item(info, "owner UID match", XT_OWNER_UID, numeric); + owner_mt_print_item(info, "owner GID match", XT_OWNER_GID, numeric); + owner_mt_print_item(info, "incl. suppl. groups", XT_OWNER_SUPPL_GROUPS, numeric); } static void @@ -487,9 +496,10 @@ static void owner_mt_save(const void *ip, const struct xt_entry_match *match) { const struct xt_owner_match_info *info = (void *)match->data; - owner_mt_print_item(info, "--socket-exists", XT_OWNER_SOCKET, true); - owner_mt_print_item(info, "--uid-owner", XT_OWNER_UID, true); - owner_mt_print_item(info, "--gid-owner", XT_OWNER_GID, true); + owner_mt_print_item(info, "--socket-exists", XT_OWNER_SOCKET, true); + owner_mt_print_item(info, "--uid-owner", XT_OWNER_UID, true); + owner_mt_print_item(info, "--gid-owner", XT_OWNER_GID, true); + owner_mt_print_item(info, "--suppl-groups", XT_OWNER_SUPPL_GROUPS, true); } static int diff --git a/extensions/libxt_owner.man b/extensions/libxt_owner.man index 49b58cee..e2479865 100644 --- a/extensions/libxt_owner.man +++ b/extensions/libxt_owner.man @@ -15,5 +15,9 @@ given user. You may also specify a numerical UID, or an UID range. Matches if the packet socket's file structure is owned by the given group. You may also specify a numerical GID, or a GID range. .TP +\fB\-\-suppl\-groups\fP +Causes group(s) specified with \fB\-\-gid-owner\fP to be also checked in the +supplementary groups of a process. +.TP [\fB!\fP] \fB\-\-socket\-exists\fP Matches if the packet is associated with a socket. diff --git a/extensions/libxt_owner.t b/extensions/libxt_owner.t index aec30b65..2779e5c1 100644 --- a/extensions/libxt_owner.t +++ b/extensions/libxt_owner.t @@ -8,5 +8,9 @@ -m owner --uid-owner 0-10 --gid-owner 0-10;=;OK -m owner ! --uid-owner root;-m owner ! --uid-owner 0;OK -m owner --socket-exists;=;OK +-m owner --gid-owner 0-10 --suppl-groups;=;OK +-m owner --suppl-groups --gid-owner 0-10;;FAIL +-m owner --gid-owner 0-10 ! --suppl-groups;;FAIL +-m owner --suppl-groups;;FAIL :INPUT -m owner --uid-owner root;;FAIL -- cgit v1.2.3