From patchwork Sat Oct 3 08:44:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Berg X-Patchwork-Id: 267649 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97023C4363D for ; Sat, 3 Oct 2020 08:44:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B053208FE for ; Sat, 3 Oct 2020 08:44:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725808AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725777AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9572C0613E8 for ; Sat, 3 Oct 2020 01:44:54 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1kOd9w-00FmcE-49; Sat, 03 Oct 2020 10:44:52 +0200 From: Johannes Berg To: netdev@vger.kernel.org Cc: Jakub Kicinski , David Ahern , Johannes Berg Subject: [PATCH v3 1/5] netlink: compare policy more accurately Date: Sat, 3 Oct 2020 10:44:42 +0200 Message-Id: <20201003104138.80819804bfa9.I78718edf29745b8e5f5ea2d289e59c8884fdd8c7@changeid> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201003084446.59042-1-johannes@sipsolutions.net> References: <20201003084446.59042-1-johannes@sipsolutions.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Johannes Berg The maxtype is really an integral part of the policy, and while we haven't gotten into a situation yet where this happens, it seems that some developer might eventually have two places pointing to identical policies, with different maxattr to exclude some attrs in one of the places. Even if not, it's really the right thing to compare both since the two data items fundamentally belong together. v2: - also do the proper comparison in get_policy_idx() Signed-off-by: Johannes Berg --- net/netlink/policy.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/netlink/policy.c b/net/netlink/policy.c index ebc64b20b6ee..753b265acec5 100644 --- a/net/netlink/policy.c +++ b/net/netlink/policy.c @@ -35,7 +35,8 @@ static int add_policy(struct netlink_policy_dump_state **statep, return 0; for (i = 0; i < state->n_alloc; i++) { - if (state->policies[i].policy == policy) + if (state->policies[i].policy == policy && + state->policies[i].maxtype == maxtype) return 0; if (!state->policies[i].policy) { @@ -63,12 +64,14 @@ static int add_policy(struct netlink_policy_dump_state **statep, } static unsigned int get_policy_idx(struct netlink_policy_dump_state *state, - const struct nla_policy *policy) + const struct nla_policy *policy, + unsigned int maxtype) { unsigned int i; for (i = 0; i < state->n_alloc; i++) { - if (state->policies[i].policy == policy) + if (state->policies[i].policy == policy && + state->policies[i].maxtype == maxtype) return i; } @@ -182,7 +185,8 @@ int netlink_policy_dump_write(struct sk_buff *skb, type = NL_ATTR_TYPE_NESTED_ARRAY; if (pt->nested_policy && pt->len && (nla_put_u32(skb, NL_POLICY_TYPE_ATTR_POLICY_IDX, - get_policy_idx(state, pt->nested_policy)) || + get_policy_idx(state, pt->nested_policy, + pt->len)) || nla_put_u32(skb, NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE, pt->len))) goto nla_put_failure; From patchwork Sat Oct 3 08:44:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Berg X-Patchwork-Id: 267647 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77E6FC4363D for ; Sat, 3 Oct 2020 08:45:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3EE1A206DB for ; Sat, 3 Oct 2020 08:45:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725796AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725601AbgJCIoy (ORCPT ); Sat, 3 Oct 2020 04:44:54 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B78B0C0613D0 for ; Sat, 3 Oct 2020 01:44:54 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1kOd9w-00FmcE-Dd; Sat, 03 Oct 2020 10:44:52 +0200 From: Johannes Berg To: netdev@vger.kernel.org Cc: Jakub Kicinski , David Ahern , Johannes Berg Subject: [PATCH v3 2/5] netlink: rework policy dump to support multiple policies Date: Sat, 3 Oct 2020 10:44:43 +0200 Message-Id: <20201003104138.c69b48fe6e9b.I525cd130f9c78d7a6acd90d735a67974e51fb73c@changeid> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201003084446.59042-1-johannes@sipsolutions.net> References: <20201003084446.59042-1-johannes@sipsolutions.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Johannes Berg Rework the policy dump code a bit to support adding multiple policies to a single dump, in order to e.g. support per-op policies in generic netlink. v2: - move kernel-doc to implementation [Jakub] - squash the first patch to not flip-flop on the prototype [Jakub] - merge netlink_policy_dump_get_policy_idx() with the old get_policy_idx() we already had - rebase without Jakub's patch to have per-op dump Signed-off-by: Johannes Berg --- include/net/netlink.h | 9 ++-- net/netlink/genetlink.c | 3 +- net/netlink/policy.c | 102 ++++++++++++++++++++++++++++++++-------- 3 files changed, 90 insertions(+), 24 deletions(-) diff --git a/include/net/netlink.h b/include/net/netlink.h index 00258590f2cb..5a5ff97cc596 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -1937,9 +1937,12 @@ void nla_get_range_signed(const struct nla_policy *pt, struct netlink_policy_dump_state; -int netlink_policy_dump_start(const struct nla_policy *policy, - unsigned int maxtype, - struct netlink_policy_dump_state **state); +int netlink_policy_dump_add_policy(struct netlink_policy_dump_state **pstate, + const struct nla_policy *policy, + unsigned int maxtype); +int netlink_policy_dump_get_policy_idx(struct netlink_policy_dump_state *state, + const struct nla_policy *policy, + unsigned int maxtype); bool netlink_policy_dump_loop(struct netlink_policy_dump_state *state); int netlink_policy_dump_write(struct sk_buff *skb, struct netlink_policy_dump_state *state); diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 7ddc574931f4..89646b97300c 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1150,7 +1150,8 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) if (!rt->policy) return -ENODATA; - return netlink_policy_dump_start(rt->policy, rt->maxattr, &ctx->state); + return netlink_policy_dump_add_policy(&ctx->state, rt->policy, + rt->maxattr); } static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) diff --git a/net/netlink/policy.c b/net/netlink/policy.c index 753b265acec5..cf23c0151721 100644 --- a/net/netlink/policy.c +++ b/net/netlink/policy.c @@ -63,44 +63,85 @@ static int add_policy(struct netlink_policy_dump_state **statep, return 0; } -static unsigned int get_policy_idx(struct netlink_policy_dump_state *state, - const struct nla_policy *policy, - unsigned int maxtype) +/** + * netlink_policy_dump_get_policy_idx - retrieve policy index + * @state: the policy dump state + * @policy: the policy to find + * @maxtype: the policy's maxattr + * + * Returns: the index of the given policy in the dump state + * + * Call this to find a policy index when you've added multiple and e.g. + * need to tell userspace which command has which policy (by index). + * + * Note: this will WARN and return 0 if the policy isn't found, which + * means it wasn't added in the first place, which would be an + * internal consistency bug. + */ +int netlink_policy_dump_get_policy_idx(struct netlink_policy_dump_state *state, + const struct nla_policy *policy, + unsigned int maxtype) { unsigned int i; + if (WARN_ON(!policy || !maxtype)) + return 0; + for (i = 0; i < state->n_alloc; i++) { if (state->policies[i].policy == policy && state->policies[i].maxtype == maxtype) return i; } - WARN_ON_ONCE(1); - return -1; + WARN_ON(1); + return 0; } -int netlink_policy_dump_start(const struct nla_policy *policy, - unsigned int maxtype, - struct netlink_policy_dump_state **statep) +static struct netlink_policy_dump_state *alloc_state(void) { struct netlink_policy_dump_state *state; + + state = kzalloc(struct_size(state, policies, INITIAL_POLICIES_ALLOC), + GFP_KERNEL); + if (!state) + return ERR_PTR(-ENOMEM); + state->n_alloc = INITIAL_POLICIES_ALLOC; + + return state; +} + +/** + * netlink_policy_dump_add_policy - add a policy to the dump + * @pstate: state to add to, may be reallocated, must be %NULL the first time + * @policy: the new policy to add to the dump + * @maxtype: the new policy's max attr type + * + * Returns: 0 on success, a negative error code otherwise. + * + * Call this to allocate a policy dump state, and to add policies to it. This + * should be called from the dump start() callback. + * + * Note: on failures, any previously allocated state is freed. + */ +int netlink_policy_dump_add_policy(struct netlink_policy_dump_state **pstate, + const struct nla_policy *policy, + unsigned int maxtype) +{ + struct netlink_policy_dump_state *state = *pstate; unsigned int policy_idx; int err; - if (*statep) - return 0; + if (!state) { + state = alloc_state(); + if (IS_ERR(state)) + return PTR_ERR(state); + } /* * walk the policies and nested ones first, and build * a linear list of them. */ - state = kzalloc(struct_size(state, policies, INITIAL_POLICIES_ALLOC), - GFP_KERNEL); - if (!state) - return -ENOMEM; - state->n_alloc = INITIAL_POLICIES_ALLOC; - err = add_policy(&state, policy, maxtype); if (err) return err; @@ -131,8 +172,7 @@ int netlink_policy_dump_start(const struct nla_policy *policy, } } - *statep = state; - + *pstate = state; return 0; } @@ -143,11 +183,26 @@ netlink_policy_dump_finished(struct netlink_policy_dump_state *state) !state->policies[state->policy_idx].policy; } +/** + * netlink_policy_dump_loop - dumping loop indicator + * @state: the policy dump state + * + * Returns: %true if the dump continues, %false otherwise + * + * Note: this frees the dump state when finishing + */ bool netlink_policy_dump_loop(struct netlink_policy_dump_state *state) { return !netlink_policy_dump_finished(state); } +/** + * netlink_policy_dump_write - write current policy dump attributes + * @skb: the message skb to write to + * @state: the policy dump state + * + * Returns: 0 on success, an error code otherwise + */ int netlink_policy_dump_write(struct sk_buff *skb, struct netlink_policy_dump_state *state) { @@ -185,8 +240,9 @@ int netlink_policy_dump_write(struct sk_buff *skb, type = NL_ATTR_TYPE_NESTED_ARRAY; if (pt->nested_policy && pt->len && (nla_put_u32(skb, NL_POLICY_TYPE_ATTR_POLICY_IDX, - get_policy_idx(state, pt->nested_policy, - pt->len)) || + netlink_policy_dump_get_policy_idx(state, + pt->nested_policy, + pt->len)) || nla_put_u32(skb, NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE, pt->len))) goto nla_put_failure; @@ -309,6 +365,12 @@ int netlink_policy_dump_write(struct sk_buff *skb, return -ENOBUFS; } +/** + * netlink_policy_dump_free - free policy dump state + * @state: the policy dump state to free + * + * Call this from the done() method to ensure dump state is freed. + */ void netlink_policy_dump_free(struct netlink_policy_dump_state *state) { kfree(state); From patchwork Sat Oct 3 08:44:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Berg X-Patchwork-Id: 289039 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B574CC4727D for ; Sat, 3 Oct 2020 08:44:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 742EE206F8 for ; Sat, 3 Oct 2020 08:44:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725817AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725791AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7534C061787 for ; Sat, 3 Oct 2020 01:44:54 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1kOd9w-00FmcE-Od; Sat, 03 Oct 2020 10:44:52 +0200 From: Johannes Berg To: netdev@vger.kernel.org Cc: Jakub Kicinski , David Ahern , Johannes Berg Subject: [PATCH v3 3/5] genetlink: factor skb preparation out of ctrl_dumppolicy() Date: Sat, 3 Oct 2020 10:44:44 +0200 Message-Id: <20201003104138.f5f85141e735.I0e59ae414404a92143c6ed8b0b0caf7e0e0d11a0@changeid> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201003084446.59042-1-johannes@sipsolutions.net> References: <20201003084446.59042-1-johannes@sipsolutions.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Johannes Berg We'll need this later for the per-op policy index dump. Reviewed-by: Jakub Kicinski Signed-off-by: Johannes Berg --- net/netlink/genetlink.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 89646b97300c..5e33c7938470 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1154,6 +1154,24 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) rt->maxattr); } +static void *ctrl_dumppolicy_prep(struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; + void *hdr; + + hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, &genl_ctrl, + NLM_F_MULTI, CTRL_CMD_GETPOLICY); + if (!hdr) + return NULL; + + if (nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, ctx->fam_id)) + return NULL; + + return hdr; +} + static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) { struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; @@ -1162,15 +1180,10 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) void *hdr; struct nlattr *nest; - hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, &genl_ctrl, - NLM_F_MULTI, CTRL_CMD_GETPOLICY); + hdr = ctrl_dumppolicy_prep(skb, cb); if (!hdr) goto nla_put_failure; - if (nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, ctx->fam_id)) - goto nla_put_failure; - nest = nla_nest_start(skb, CTRL_ATTR_POLICY); if (!nest) goto nla_put_failure; From patchwork Sat Oct 3 08:44:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Berg X-Patchwork-Id: 267648 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 413F8C4363D for ; Sat, 3 Oct 2020 08:44:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1117320738 for ; Sat, 3 Oct 2020 08:44:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725803AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725778AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C1D2DC0613E7 for ; Sat, 3 Oct 2020 01:44:54 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1kOd9x-00FmcE-15; Sat, 03 Oct 2020 10:44:53 +0200 From: Johannes Berg To: netdev@vger.kernel.org Cc: Jakub Kicinski , David Ahern , Johannes Berg Subject: [PATCH v3 4/5] genetlink: properly support per-op policy dumping Date: Sat, 3 Oct 2020 10:44:45 +0200 Message-Id: <20201003104138.7f59292a5c88.I19674e30193a115c120d976d1e3ebc9ec7c8235e@changeid> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201003084446.59042-1-johannes@sipsolutions.net> References: <20201003084446.59042-1-johannes@sipsolutions.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Johannes Berg Add support for per-op policy dumping. The data is pretty much as before, except that now the assumption that the policy with index 0 is "the" policy no longer holds - you now need to look at the new CTRL_ATTR_OP_POLICY attribute which is a nested attr (indexed by op) containing attributes for do and dump policies. When a single op is requested, the CTRL_ATTR_OP_POLICY will be added in the same way, since do and dump policies may differ. v2: - conditionally advertise per-command policies only if there actually is a policy being used for the do/dump and it's present at all Signed-off-by: Johannes Berg --- include/uapi/linux/genetlink.h | 10 ++++ net/netlink/genetlink.c | 102 +++++++++++++++++++++++++++++---- 2 files changed, 102 insertions(+), 10 deletions(-) diff --git a/include/uapi/linux/genetlink.h b/include/uapi/linux/genetlink.h index 9c0636ec2286..bc9c98e84828 100644 --- a/include/uapi/linux/genetlink.h +++ b/include/uapi/linux/genetlink.h @@ -64,6 +64,7 @@ enum { CTRL_ATTR_OPS, CTRL_ATTR_MCAST_GROUPS, CTRL_ATTR_POLICY, + CTRL_ATTR_OP_POLICY, __CTRL_ATTR_MAX, }; @@ -85,6 +86,15 @@ enum { __CTRL_ATTR_MCAST_GRP_MAX, }; +enum { + CTRL_ATTR_POLICY_UNSPEC, + CTRL_ATTR_POLICY_DO, + CTRL_ATTR_POLICY_DUMP, + + __CTRL_ATTR_POLICY_DUMP_MAX, + CTRL_ATTR_POLICY_DUMP_MAX = __CTRL_ATTR_POLICY_DUMP_MAX - 1 +}; + #define CTRL_ATTR_MCAST_GRP_MAX (__CTRL_ATTR_MCAST_GRP_MAX - 1) diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 5e33c7938470..eb916c44884f 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1112,7 +1112,10 @@ static int genl_ctrl_event(int event, const struct genl_family *family, struct ctrl_dump_policy_ctx { struct netlink_policy_dump_state *state; + const struct genl_family *rt; + unsigned int opidx; u16 fam_id; + u8 policies:1; }; static const struct nla_policy ctrl_policy_policy[] = { @@ -1127,6 +1130,8 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; struct nlattr **tb = info->attrs; const struct genl_family *rt; + struct genl_ops op; + int err, i; BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx)); @@ -1147,11 +1152,23 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) if (!rt) return -ENOENT; - if (!rt->policy) - return -ENODATA; + ctx->rt = rt; + + for (i = 0; i < genl_get_cmd_cnt(rt); i++) { + genl_get_cmd_by_index(i, rt, &op); + + if (op.policy) { + err = netlink_policy_dump_add_policy(&ctx->state, + op.policy, + op.maxattr); + if (err) + return err; + } + } - return netlink_policy_dump_add_policy(&ctx->state, rt->policy, - rt->maxattr); + if (!ctx->state) + return -ENODATA; + return 0; } static void *ctrl_dumppolicy_prep(struct sk_buff *skb, @@ -1172,12 +1189,78 @@ static void *ctrl_dumppolicy_prep(struct sk_buff *skb, return hdr; } +static int ctrl_dumppolicy_put_op(struct sk_buff *skb, + struct netlink_callback *cb, + struct genl_ops *op) +{ + struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; + struct nlattr *nest_pol, *nest_op; + void *hdr; + int idx; + + /* skip if we have nothing to show */ + if (!op->policy) + return 0; + if (!op->doit && + (!op->dumpit || op->validate & GENL_DONT_VALIDATE_DUMP)) + return 0; + + hdr = ctrl_dumppolicy_prep(skb, cb); + if (!hdr) + return -ENOBUFS; + + nest_pol = nla_nest_start(skb, CTRL_ATTR_OP_POLICY); + if (!nest_pol) + goto err; + + nest_op = nla_nest_start(skb, op->cmd); + if (!nest_op) + goto err; + + /* for now both do/dump are always the same */ + idx = netlink_policy_dump_get_policy_idx(ctx->state, + op->policy, + op->maxattr); + + if (op->doit && nla_put_u32(skb, CTRL_ATTR_POLICY_DO, idx)) + goto err; + + if (op->dumpit && !(op->validate & GENL_DONT_VALIDATE_DUMP) && + nla_put_u32(skb, CTRL_ATTR_POLICY_DUMP, idx)) + goto err; + + nla_nest_end(skb, nest_op); + nla_nest_end(skb, nest_pol); + genlmsg_end(skb, hdr); + + return 0; +err: + genlmsg_cancel(skb, hdr); + return -ENOBUFS; +} + static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) { struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx; + void *hdr; + + if (!ctx->policies) { + while (ctx->opidx < genl_get_cmd_cnt(ctx->rt)) { + struct genl_ops op; + + genl_get_cmd_by_index(ctx->opidx, ctx->rt, &op); + + if (ctrl_dumppolicy_put_op(skb, cb, &op)) + return skb->len; + + ctx->opidx++; + } + + /* completed with the per-op policy index list */ + ctx->policies = true; + } while (netlink_policy_dump_loop(ctx->state)) { - void *hdr; struct nlattr *nest; hdr = ctrl_dumppolicy_prep(skb, cb); @@ -1194,14 +1277,13 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) nla_nest_end(skb, nest); genlmsg_end(skb, hdr); - continue; - -nla_put_failure: - genlmsg_cancel(skb, hdr); - break; } return skb->len; + +nla_put_failure: + genlmsg_cancel(skb, hdr); + return skb->len; } static int ctrl_dumppolicy_done(struct netlink_callback *cb) From patchwork Sat Oct 3 08:44:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Berg X-Patchwork-Id: 289038 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3975AC41604 for ; Sat, 3 Oct 2020 08:45:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A9CB206DB for ; Sat, 3 Oct 2020 08:45:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725822AbgJCIpA (ORCPT ); Sat, 3 Oct 2020 04:45:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725601AbgJCIoz (ORCPT ); Sat, 3 Oct 2020 04:44:55 -0400 Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14C86C0613D0 for ; Sat, 3 Oct 2020 01:44:55 -0700 (PDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94) (envelope-from ) id 1kOd9x-00FmcE-BA; Sat, 03 Oct 2020 10:44:53 +0200 From: Johannes Berg To: netdev@vger.kernel.org Cc: Jakub Kicinski , David Ahern Subject: [PATCH v3 5/5] genetlink: allow dumping command-specific policy Date: Sat, 3 Oct 2020 10:44:46 +0200 Message-Id: <20201003084446.59042-2-johannes@sipsolutions.net> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201003084446.59042-1-johannes@sipsolutions.net> References: <20201003084446.59042-1-johannes@sipsolutions.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jakub Kicinski Right now CTRL_CMD_GETPOLICY can only dump the family-wide policy. Support dumping policy of a specific op. v3: - rebase after per-op policy export and handle that v2: - make cmd U32, just in case. v1: - don't echo op in the output in a naive way, this should make it cleaner to extend the output format for dumping policies for all the commands at once in the future. Signed-off-by: Jakub Kicinski Link: https://lore.kernel.org/r/20201001225933.1373426-11-kuba@kernel.org Signed-off-by: Johannes Berg --- include/uapi/linux/genetlink.h | 1 + net/netlink/genetlink.c | 41 +++++++++++++++++++++++++++++----- 2 files changed, 37 insertions(+), 5 deletions(-) diff --git a/include/uapi/linux/genetlink.h b/include/uapi/linux/genetlink.h index bc9c98e84828..d83f214b4134 100644 --- a/include/uapi/linux/genetlink.h +++ b/include/uapi/linux/genetlink.h @@ -65,6 +65,7 @@ enum { CTRL_ATTR_MCAST_GROUPS, CTRL_ATTR_POLICY, CTRL_ATTR_OP_POLICY, + CTRL_ATTR_OP, __CTRL_ATTR_MAX, }; diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index eb916c44884f..c992424e4d63 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -123,7 +123,7 @@ static void genl_op_from_full(const struct genl_family *family, op->policy = family->policy; } -static int genl_get_cmd_full(u8 cmd, const struct genl_family *family, +static int genl_get_cmd_full(u32 cmd, const struct genl_family *family, struct genl_ops *op) { int i; @@ -152,7 +152,7 @@ static void genl_op_from_small(const struct genl_family *family, op->policy = family->policy; } -static int genl_get_cmd_small(u8 cmd, const struct genl_family *family, +static int genl_get_cmd_small(u32 cmd, const struct genl_family *family, struct genl_ops *op) { int i; @@ -166,7 +166,7 @@ static int genl_get_cmd_small(u8 cmd, const struct genl_family *family, return -ENOENT; } -static int genl_get_cmd(u8 cmd, const struct genl_family *family, +static int genl_get_cmd(u32 cmd, const struct genl_family *family, struct genl_ops *op) { if (!genl_get_cmd_full(cmd, family, op)) @@ -1114,14 +1114,17 @@ struct ctrl_dump_policy_ctx { struct netlink_policy_dump_state *state; const struct genl_family *rt; unsigned int opidx; + u32 op; u16 fam_id; - u8 policies:1; + u8 policies:1, + single_op:1; }; static const struct nla_policy ctrl_policy_policy[] = { [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, .len = GENL_NAMSIZ - 1 }, + [CTRL_ATTR_OP] = { .type = NLA_U32 }, }; static int ctrl_dumppolicy_start(struct netlink_callback *cb) @@ -1154,6 +1157,23 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb) ctx->rt = rt; + if (tb[CTRL_ATTR_OP]) { + ctx->single_op = true; + ctx->op = nla_get_u32(tb[CTRL_ATTR_OP]); + + err = genl_get_cmd(ctx->op, rt, &op); + if (err) { + NL_SET_BAD_ATTR(cb->extack, tb[CTRL_ATTR_OP]); + return err; + } + + if (!op.policy) + return -ENODATA; + + return netlink_policy_dump_add_policy(&ctx->state, op.policy, + op.maxattr); + } + for (i = 0; i < genl_get_cmd_cnt(rt); i++) { genl_get_cmd_by_index(i, rt, &op); @@ -1248,7 +1268,18 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) while (ctx->opidx < genl_get_cmd_cnt(ctx->rt)) { struct genl_ops op; - genl_get_cmd_by_index(ctx->opidx, ctx->rt, &op); + if (ctx->single_op) { + int err; + + err = genl_get_cmd(ctx->op, ctx->rt, &op); + if (WARN_ON(err)) + return skb->len; + + /* break out of the loop after this one */ + ctx->opidx = genl_get_cmd_cnt(ctx->rt); + } else { + genl_get_cmd_by_index(ctx->opidx, ctx->rt, &op); + } if (ctrl_dumppolicy_put_op(skb, cb, &op)) return skb->len;