From patchwork Wed Nov 29 17:33:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vadim Fedorenko X-Patchwork-Id: 749254 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b="kZwUFzBl" Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49E4DCA; Wed, 29 Nov 2023 09:33:37 -0800 (PST) Received: from pps.filterd (m0109334.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3ATH2OnP017424; Wed, 29 Nov 2023 09:33:29 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding : content-type; s=s2048-2021-q4; bh=WZEgQAQDfE1OgZhe9R1OJ+myHgMJg8kivq3udIKGcsY=; b=kZwUFzBlOtTFOT7HGp2WlGpeNjhpkfGl8GXxgJcUxswof7pnEM6V7qTLsi27mSnvRSQx 8TP1Dlvr+QUMJxlT3vSoqQMNIp6usUeLMB0QFPRs3Ii6Q3aEN30Zpbs5OywfK6V5qYMW i1RPx/hY4+PAXxExUcPv58XTfqjG8xh/Fp8W5D74DqWIU6uiNaDTeCnAqD2PxuUgFFJr q1UvyCaAPOjAuGIUYpjXNX//xQGQkCWhpWhD7YDDH0VzkWuGubsIcIeJIIgbILDudPI9 TgkjSAAkrNHKMX+NRGCQrh6OO4y2w734WGgLyq4ne+Vxa+GvySS89frKL/l4S4fHcfV2 qg== Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3unnkgq0bb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Wed, 29 Nov 2023 09:33:28 -0800 Received: from devvm4158.cln0.facebook.com (2620:10d:c085:108::4) by mail.thefacebook.com (2620:10d:c085:11d::8) with Microsoft SMTP Server id 15.1.2507.34; Wed, 29 Nov 2023 09:33:26 -0800 From: Vadim Fedorenko To: Vadim Fedorenko , Jakub Kicinski , Martin KaFai Lau , Andrii Nakryiko , Alexei Starovoitov , Mykola Lysenko , Herbert Xu CC: Vadim Fedorenko , , , Subject: [PATCH bpf-next v6 1/3] bpf: make common crypto API for TC/XDP programs Date: Wed, 29 Nov 2023 09:33:10 -0800 Message-ID: <20231129173312.31008-1-vadfed@meta.com> X-Mailer: git-send-email 2.39.3 Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: W5elcCDLhivX0Q71HUEMXtapUaG_gmfW X-Proofpoint-ORIG-GUID: W5elcCDLhivX0Q71HUEMXtapUaG_gmfW X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-29_15,2023-11-29_01,2023-05-22_02 Add crypto API support to BPF to be able to decrypt or encrypt packets in TC/XDP BPF programs. Special care should be taken for initialization part of crypto algo because crypto alloc) doesn't work with preemtion disabled, it can be run only in sleepable BPF program. Also async crypto is not supported because of the very same issue - TC/XDP BPF programs are not sleepable. Signed-off-by: Vadim Fedorenko --- v5 -> v6: - replace lskcipher with infrastructure to provide pluggable cipher types - add BPF skcipher as plug-in module in a separate patch v4 -> v5: - replace crypto API to use lskcipher (suggested by Herbert Xu) - remove SG list usage and provide raw buffers v3 -> v4: - reuse __bpf_dynptr_data and remove own implementation - use const __str to provide algorithm name - use kfunc macroses to avoid compilator warnings v2 -> v3: - fix kdoc issues v1 -> v2: - use kmalloc in sleepable func, suggested by Alexei - use __bpf_dynptr_is_rdonly() to check destination, suggested by Jakub - use __bpf_dynptr_data_ptr() for all dynptr accesses --- include/linux/bpf.h | 1 + include/linux/bpf_crypto.h | 23 +++ kernel/bpf/Makefile | 3 + kernel/bpf/crypto.c | 364 +++++++++++++++++++++++++++++++++++++ kernel/bpf/helpers.c | 2 +- kernel/bpf/verifier.c | 1 + 6 files changed, 393 insertions(+), 1 deletion(-) create mode 100644 include/linux/bpf_crypto.h create mode 100644 kernel/bpf/crypto.c diff --git a/include/linux/bpf.h b/include/linux/bpf.h index eb447b0a9423..0143ff6c93a1 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1228,6 +1228,7 @@ int bpf_dynptr_check_size(u32 size); u32 __bpf_dynptr_size(const struct bpf_dynptr_kern *ptr); const void *__bpf_dynptr_data(const struct bpf_dynptr_kern *ptr, u32 len); void *__bpf_dynptr_data_rw(const struct bpf_dynptr_kern *ptr, u32 len); +bool __bpf_dynptr_is_rdonly(const struct bpf_dynptr_kern *ptr); #ifdef CONFIG_BPF_JIT int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr); diff --git a/include/linux/bpf_crypto.h b/include/linux/bpf_crypto.h new file mode 100644 index 000000000000..e81bd8ab979c --- /dev/null +++ b/include/linux/bpf_crypto.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ +#ifndef _BPF_CRYPTO_H +#define _BPF_CRYPTO_H + +struct bpf_crypto_type { + void *(*alloc_tfm)(const char *algo); + void (*free_tfm)(void *tfm); + int (*has_algo)(const char *algo); + int (*setkey)(void *tfm, const u8 *key, unsigned int keylen); + int (*setauthsize)(void *tfm, unsigned int authsize); + int (*encrypt)(void *tfm, const u8 *src, u8 *dst, unsigned int len, u8 *iv); + int (*decrypt)(void *tfm, const u8 *src, u8 *dst, unsigned int len, u8 *iv); + unsigned int (*ivsize)(void *tfm); + u32 (*get_flags)(void *tfm); + struct module *owner; + char name[14]; +}; + +int bpf_crypto_register_type(const struct bpf_crypto_type *type); +int bpf_crypto_unregister_type(const struct bpf_crypto_type *type); + +#endif /* _BPF_CRYPTO_H */ diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index f526b7573e97..bcde762bb2c2 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -41,6 +41,9 @@ obj-$(CONFIG_BPF_SYSCALL) += bpf_struct_ops.o obj-$(CONFIG_BPF_SYSCALL) += cpumask.o obj-${CONFIG_BPF_LSM} += bpf_lsm.o endif +ifeq ($(CONFIG_CRYPTO),y) +obj-$(CONFIG_BPF_SYSCALL) += crypto.o +endif obj-$(CONFIG_BPF_PRELOAD) += preload/ obj-$(CONFIG_BPF_SYSCALL) += relo_core.o diff --git a/kernel/bpf/crypto.c b/kernel/bpf/crypto.c new file mode 100644 index 000000000000..46b4d263e472 --- /dev/null +++ b/kernel/bpf/crypto.c @@ -0,0 +1,364 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2023 Meta, Inc */ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct bpf_crypto_type_list { + const struct bpf_crypto_type *type; + struct list_head list; +}; + +static LIST_HEAD(bpf_crypto_types); +static DECLARE_RWSEM(bpf_crypto_types_sem); + +/** + * struct bpf_crypto_ctx - refcounted BPF crypto context structure + * @type: The pointer to bpf crypto type + * @tfm: The pointer to instance of crypto API struct. + * @rcu: The RCU head used to free the crypto context with RCU safety. + * @usage: Object reference counter. When the refcount goes to 0, the + * memory is released back to the BPF allocator, which provides + * RCU safety. + */ +struct bpf_crypto_ctx { + const struct bpf_crypto_type *type; + void *tfm; + struct rcu_head rcu; + refcount_t usage; +}; + +int bpf_crypto_register_type(const struct bpf_crypto_type *type) +{ + struct bpf_crypto_type_list *node; + int err = -EEXIST; + + down_write(&bpf_crypto_types_sem); + list_for_each_entry(node, &bpf_crypto_types, list) { + if (!strcmp(node->type->name, type->name)) + goto unlock; + } + + node = kmalloc(sizeof(*node), GFP_KERNEL); + err = -ENOMEM; + if (!node) + goto unlock; + + node->type = type; + list_add(&node->list, &bpf_crypto_types); + err = 0; + +unlock: + up_write(&bpf_crypto_types_sem); + + return err; +} +EXPORT_SYMBOL_GPL(bpf_crypto_register_type); + +int bpf_crypto_unregister_type(const struct bpf_crypto_type *type) +{ + struct bpf_crypto_type_list *node; + int err = -ENOENT; + + down_write(&bpf_crypto_types_sem); + list_for_each_entry(node, &bpf_crypto_types, list) { + if (strcmp(node->type->name, type->name)) + continue; + + list_del(&node->list); + kfree(node); + err = 0; + break; + } + up_write(&bpf_crypto_types_sem); + + return err; +} +EXPORT_SYMBOL_GPL(bpf_crypto_unregister_type); + +static const struct bpf_crypto_type *bpf_crypto_get_type(const char *name) +{ + const struct bpf_crypto_type *type = ERR_PTR(-ENOENT); + struct bpf_crypto_type_list *node; + + down_read(&bpf_crypto_types_sem); + list_for_each_entry(node, &bpf_crypto_types, list) { + if (strcmp(node->type->name, name)) + continue; + + if (try_module_get(node->type->owner)) + type = node->type; + break; + } + up_read(&bpf_crypto_types_sem); + + return type; +} + +__bpf_kfunc_start_defs(); + +/** + * bpf_crypto_ctx_create() - Create a mutable BPF crypto context. + * + * Allocates a crypto context that can be used, acquired, and released by + * a BPF program. The crypto context returned by this function must either + * be embedded in a map as a kptr, or freed with bpf_crypto_ctx_release(). + * As crypto API functions use GFP_KERNEL allocations, this function can + * only be used in sleepable BPF programs. + * + * bpf_crypto_ctx_create() allocates memory for crypto context. + * It may return NULL if no memory is available. + * @type__str: pointer to string representation of crypto type. + * @algo__str: pointer to string representation of algorithm. + * @pkey: bpf_dynptr which holds cipher key to do crypto. + * @err: integer to store error code when NULL is returned + */ +__bpf_kfunc struct bpf_crypto_ctx * +bpf_crypto_ctx_create(const char *type__str, const char *algo__str, + const struct bpf_dynptr_kern *pkey, + unsigned int authsize, int *err) +{ + const struct bpf_crypto_type *type = bpf_crypto_get_type(type__str); + struct bpf_crypto_ctx *ctx; + const u8 *key; + u32 key_len; + + //type = bpf_crypto_get_type(type__str); + if (IS_ERR(type)) { + *err = PTR_ERR(type); + return NULL; + } + + if (!type->has_algo(algo__str)) { + *err = -EOPNOTSUPP; + goto err; + } + + if (!authsize && type->setauthsize) { + *err = -EOPNOTSUPP; + goto err; + } + + if (authsize && !type->setauthsize) { + *err = -EOPNOTSUPP; + goto err; + } + + key_len = __bpf_dynptr_size(pkey); + if (!key_len) { + *err = -EINVAL; + goto err; + } + key = __bpf_dynptr_data(pkey, key_len); + if (!key) { + *err = -EINVAL; + goto err; + } + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + if (!ctx) { + *err = -ENOMEM; + goto err; + } + + ctx->type = type; + ctx->tfm = type->alloc_tfm(algo__str); + if (IS_ERR(ctx->tfm)) { + *err = PTR_ERR(ctx->tfm); + ctx->tfm = NULL; + goto err; + } + + if (authsize) { + *err = type->setauthsize(ctx->tfm, authsize; + if (*err) + goto err; + } + + *err = type->setkey(ctx->tfm, key, key_len); + if (*err) + goto err; + + refcount_set(&ctx->usage, 1); + + return ctx; +err: + if (ctx->tfm) + type->free_tfm(ctx->tfm); + kfree(ctx); + module_put(type->owner); + + return NULL; +} + +static void crypto_free_cb(struct rcu_head *head) +{ + struct bpf_crypto_ctx *ctx; + + ctx = container_of(head, struct bpf_crypto_ctx, rcu); + ctx->type->free_tfm(ctx->tfm); + module_put(ctx->type->owner); + kfree(ctx); +} + +/** + * bpf_crypto_ctx_acquire() - Acquire a reference to a BPF crypto context. + * @ctx: The BPF crypto context being acquired. The ctx must be a trusted + * pointer. + * + * Acquires a reference to a BPF crypto context. The context returned by this function + * must either be embedded in a map as a kptr, or freed with + * bpf_crypto_skcipher_ctx_release(). + */ +__bpf_kfunc struct bpf_crypto_ctx * +bpf_crypto_ctx_acquire(struct bpf_crypto_ctx *ctx) +{ + refcount_inc(&ctx->usage); + return ctx; +} + +/** + * bpf_crypto_ctx_release() - Release a previously acquired BPF crypto context. + * @ctx: The crypto context being released. + * + * Releases a previously acquired reference to a BPF crypto context. When the final + * reference of the BPF crypto context has been released, it is subsequently freed in + * an RCU callback in the BPF memory allocator. + */ +__bpf_kfunc void bpf_crypto_ctx_release(struct bpf_crypto_ctx *ctx) +{ + if (refcount_dec_and_test(&ctx->usage)) + call_rcu(&ctx->rcu, crypto_free_cb); +} + +static int bpf_crypto_crypt(const struct bpf_crypto_ctx *ctx, + const struct bpf_dynptr_kern *src, + struct bpf_dynptr_kern *dst, + const struct bpf_dynptr_kern *iv, + bool decrypt) +{ + u32 src_len, dst_len, iv_len; + const u8 *psrc; + u8 *pdst, *piv; + int err; + + if (ctx->type->get_flags(ctx->tfm) & CRYPTO_TFM_NEED_KEY) + return -EINVAL; + + if (__bpf_dynptr_is_rdonly(dst)) + return -EINVAL; + + iv_len = __bpf_dynptr_size(iv); + src_len = __bpf_dynptr_size(src); + dst_len = __bpf_dynptr_size(dst); + if (!src_len || !dst_len) + return -EINVAL; + + if (iv_len != ctx->type->ivsize(ctx->tfm)) + return -EINVAL; + + psrc = __bpf_dynptr_data(src, src_len); + if (!psrc) + return -EINVAL; + pdst = __bpf_dynptr_data_rw(dst, dst_len); + if (!pdst) + return -EINVAL; + + piv = iv_len ? __bpf_dynptr_data_rw(iv, iv_len) : NULL; + if (iv_len && !piv) + return -EINVAL; + + err = decrypt ? ctx->type->decrypt(ctx->tfm, psrc, pdst, src_len, piv) + : ctx->type->encrypt(ctx->tfm, psrc, pdst, src_len, piv); + + return err; +} + +/** + * bpf_crypto_decrypt() - Decrypt buffer using configured context and IV provided. + * @ctx: The crypto context being used. The ctx must be a trusted pointer. + * @src: bpf_dynptr to the encrypted data. Must be a trusted pointer. + * @dst: bpf_dynptr to the buffer where to store the result. Must be a trusted pointer. + * @iv: bpf_dynptr to IV data to be used by decryptor. + * + * Decrypts provided buffer using IV data and the crypto context. Crypto context must be configured. + */ +__bpf_kfunc int bpf_crypto_decrypt(struct bpf_crypto_ctx *ctx, + const struct bpf_dynptr_kern *src, + struct bpf_dynptr_kern *dst, + struct bpf_dynptr_kern *iv) +{ + return bpf_crypto_crypt(ctx, src, dst, iv, true); +} + +/** + * bpf_crypto_encrypt() - Encrypt buffer using configured context and IV provided. + * @ctx: The crypto context being used. The ctx must be a trusted pointer. + * @src: bpf_dynptr to the plain data. Must be a trusted pointer. + * @dst: bpf_dynptr to buffer where to store the result. Must be a trusted pointer. + * @iv: bpf_dynptr to IV data to be used by decryptor. + * + * Encrypts provided buffer using IV data and the crypto context. Crypto context must be configured. + */ +__bpf_kfunc int bpf_crypto_encrypt(struct bpf_crypto_ctx *ctx, + const struct bpf_dynptr_kern *src, + struct bpf_dynptr_kern *dst, + struct bpf_dynptr_kern *iv) +{ + return bpf_crypto_crypt(ctx, src, dst, iv, false); +} + +__bpf_kfunc_end_defs(); + +BTF_SET8_START(crypt_init_kfunc_btf_ids) +BTF_ID_FLAGS(func, bpf_crypto_ctx_create, KF_ACQUIRE | KF_RET_NULL | KF_SLEEPABLE) +BTF_ID_FLAGS(func, bpf_crypto_ctx_release, KF_RELEASE) +BTF_ID_FLAGS(func, bpf_crypto_ctx_acquire, KF_ACQUIRE | KF_TRUSTED_ARGS) +BTF_SET8_END(crypt_init_kfunc_btf_ids) + +static const struct btf_kfunc_id_set crypt_init_kfunc_set = { + .owner = THIS_MODULE, + .set = &crypt_init_kfunc_btf_ids, +}; + +BTF_SET8_START(crypt_kfunc_btf_ids) +BTF_ID_FLAGS(func, bpf_crypto_decrypt, KF_RCU) +BTF_ID_FLAGS(func, bpf_crypto_encrypt, KF_RCU) +BTF_SET8_END(crypt_kfunc_btf_ids) + +static const struct btf_kfunc_id_set crypt_kfunc_set = { + .owner = THIS_MODULE, + .set = &crypt_kfunc_btf_ids, +}; + +BTF_ID_LIST(bpf_crypto_dtor_ids) +BTF_ID(struct, bpf_crypto_ctx) +BTF_ID(func, bpf_crypto_ctx_release) + +static int __init crypto_kfunc_init(void) +{ + int ret; + const struct btf_id_dtor_kfunc bpf_crypto_dtors[] = { + { + .btf_id = bpf_crypto_dtor_ids[0], + .kfunc_btf_id = bpf_crypto_dtor_ids[1] + }, + }; + + ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &crypt_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_ACT, &crypt_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &crypt_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, + &crypt_init_kfunc_set); + return ret ?: register_btf_id_dtor_kfuncs(bpf_crypto_dtors, + ARRAY_SIZE(bpf_crypto_dtors), + THIS_MODULE); +} + +late_initcall(crypto_kfunc_init); diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index b45a8381f9bd..b73314c0124e 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -1436,7 +1436,7 @@ static const struct bpf_func_proto bpf_kptr_xchg_proto = { #define DYNPTR_SIZE_MASK 0xFFFFFF #define DYNPTR_RDONLY_BIT BIT(31) -static bool __bpf_dynptr_is_rdonly(const struct bpf_dynptr_kern *ptr) +bool __bpf_dynptr_is_rdonly(const struct bpf_dynptr_kern *ptr) { return ptr->size & DYNPTR_RDONLY_BIT; } diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 8e7b6072e3f4..c54716966d5d 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5162,6 +5162,7 @@ BTF_ID(struct, cgroup) #endif BTF_ID(struct, bpf_cpumask) BTF_ID(struct, task_struct) +BTF_ID(struct, bpf_crypto_ctx) BTF_SET_END(rcu_protected_types) static bool rcu_protected_object(const struct btf *btf, u32 btf_id) From patchwork Wed Nov 29 17:33:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vadim Fedorenko X-Patchwork-Id: 749253 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b="ZeR2ftPO" Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7072C10A; Wed, 29 Nov 2023 09:33:49 -0800 (PST) Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3ATH2Md8012840; 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Wed, 29 Nov 2023 09:33:31 -0800 From: Vadim Fedorenko To: Vadim Fedorenko , Jakub Kicinski , Martin KaFai Lau , Andrii Nakryiko , Alexei Starovoitov , Mykola Lysenko , Herbert Xu CC: Vadim Fedorenko , , , Subject: [PATCH bpf-next v6 3/3] selftests: bpf: crypto skcipher algo selftests Date: Wed, 29 Nov 2023 09:33:12 -0800 Message-ID: <20231129173312.31008-3-vadfed@meta.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20231129173312.31008-1-vadfed@meta.com> References: <20231129173312.31008-1-vadfed@meta.com> Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-ORIG-GUID: tyyLe2lkeEbrN4KGo5Cgwr3WrGrbZS-E X-Proofpoint-GUID: tyyLe2lkeEbrN4KGo5Cgwr3WrGrbZS-E X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-29_15,2023-11-29_01,2023-05-22_02 Add simple tc hook selftests to show the way to work with new crypto BPF API. Some weird structre and map are added to setup program to make verifier happy about dynptr initialization from memory. Simple AES-ECB algo is used to demonstrate encryption and decryption of fixed size buffers. Signed-off-by: Vadim Fedorenko --- v5 -> v6: - use AF_ALG socket to confirm proper algorithm test - adjust test kernel config to include AF_ALG v4 -> v5: - adjust selftests to use new naming - restore tests on aarch64 and s390 as no sg lists are used v3 -> v4: - adjust selftests to use new syntax of helpers - add tests for acquire and release v2 -> v3: - disable tests on s390 and aarch64 because of unknown Fatal exception in sg_init_one v1 -> v2: - add CONFIG_CRYPTO_AES and CONFIG_CRYPTO_ECB to selftest build config suggested by Daniel --- tools/testing/selftests/bpf/config | 5 + .../selftests/bpf/prog_tests/crypto_sanity.c | 215 ++++++++++++++++++ .../selftests/bpf/progs/crypto_common.h | 67 ++++++ .../selftests/bpf/progs/crypto_sanity.c | 192 ++++++++++++++++ 4 files changed, 479 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/crypto_sanity.c create mode 100644 tools/testing/selftests/bpf/progs/crypto_common.h create mode 100644 tools/testing/selftests/bpf/progs/crypto_sanity.c diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 3ec5927ec3e5..6963d6192975 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -13,7 +13,12 @@ CONFIG_BPF_SYSCALL=y CONFIG_CGROUP_BPF=y CONFIG_CRYPTO_HMAC=y CONFIG_CRYPTO_SHA256=y +CONFIG_CRYPTO_USER_API=y CONFIG_CRYPTO_USER_API_HASH=y +CONFIG_CRYPTO_USER_API_SKCIPHER=y +CONFIG_CRYPTO_SKCIPHER=y +CONFIG_CRYPTO_ECB=y +CONFIG_CRYPTO_AES=y CONFIG_DEBUG_INFO=y CONFIG_DEBUG_INFO_BTF=y CONFIG_DEBUG_INFO_DWARF4=y diff --git a/tools/testing/selftests/bpf/prog_tests/crypto_sanity.c b/tools/testing/selftests/bpf/prog_tests/crypto_sanity.c new file mode 100644 index 000000000000..2dd73cb248be --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/crypto_sanity.c @@ -0,0 +1,215 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include +#include +#include +#include +#include + +#include "test_progs.h" +#include "network_helpers.h" +#include "crypto_sanity.skel.h" + +#define NS_TEST "crypto_sanity_ns" +#define IPV6_IFACE_ADDR "face::1" +#define UDP_TEST_PORT 7777 +static const unsigned char crypto_key[] = "testtest12345678"; +static const char plain_text[] = "stringtoencrypt0"; +static int opfd, tfmfd; + +int init_afalg(void) +{ + struct sockaddr_alg sa = { + .salg_family = AF_ALG, + .salg_type = "skcipher", + .salg_name = "ecb(aes)" + }; + + tfmfd = socket(AF_ALG, SOCK_SEQPACKET, 0); + if (tfmfd == -1) + return errno; + if (bind(tfmfd, (struct sockaddr *)&sa, sizeof(sa)) == -1) + return errno; + if (setsockopt(tfmfd, SOL_ALG, ALG_SET_KEY, crypto_key, 16) == -1) + return errno; + opfd = accept(tfmfd, NULL, 0); + if (opfd == -1) + return errno; + return 0; +} + +void deinit_afalg(void) +{ + if (tfmfd) + close(tfmfd); + if (opfd) + close(opfd); +} + +void do_crypt_afalg(const void *src, void *dst, int size, bool encrypt) +{ + struct msghdr msg = {}; + struct cmsghdr *cmsg; + char cbuf[CMSG_SPACE(4)] = {0}; + struct iovec iov; + + msg.msg_control = cbuf; + msg.msg_controllen = sizeof(cbuf); + + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = SOL_ALG; + cmsg->cmsg_type = ALG_SET_OP; + cmsg->cmsg_len = CMSG_LEN(4); + *(__u32 *)CMSG_DATA(cmsg) = encrypt ? ALG_OP_ENCRYPT : ALG_OP_DECRYPT; + + iov.iov_base = (char *)src; + iov.iov_len = size; + + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + + sendmsg(opfd, &msg, 0); + read(opfd, dst, size); +} + +void test_crypto_sanity(void) +{ + LIBBPF_OPTS(bpf_tc_hook, qdisc_hook, .attach_point = BPF_TC_EGRESS); + LIBBPF_OPTS(bpf_tc_opts, tc_attach_enc); + LIBBPF_OPTS(bpf_tc_opts, tc_attach_dec); + LIBBPF_OPTS(bpf_test_run_opts, opts, + .repeat = 1, + ); + struct nstoken *nstoken = NULL; + struct crypto_sanity *skel; + char afalg_plain[16] = {0}; + char afalg_dst[16] = {0}; + struct sockaddr_in6 addr; + int sockfd, err, pfd; + socklen_t addrlen; + + skel = crypto_sanity__open(); + if (!ASSERT_OK_PTR(skel, "skel open")) + return; + + bpf_program__set_autoload(skel->progs.crypto_accuire, true); + + err = crypto_sanity__load(skel); + if (!ASSERT_ERR(err, "crypto_accuire unexpected load success")) + goto fail; + + crypto_sanity__destroy(skel); + + skel = crypto_sanity__open(); + if (!ASSERT_OK_PTR(skel, "skel open")) + return; + + bpf_program__set_autoload(skel->progs.crypto_accuire, false); + + SYS(fail, "ip netns add %s", NS_TEST); + SYS(fail, "ip -net %s -6 addr add %s/128 dev lo nodad", NS_TEST, IPV6_IFACE_ADDR); + SYS(fail, "ip -net %s link set dev lo up", NS_TEST); + + err = crypto_sanity__load(skel); + if (!ASSERT_OK(err, "crypto_sanity__load")) + goto fail; + + nstoken = open_netns(NS_TEST); + if (!ASSERT_OK_PTR(nstoken, "open_netns")) + goto fail; + + err = init_afalg(); + if (!ASSERT_OK(err, "AF_ALG init fail")) + goto fail; + + qdisc_hook.ifindex = if_nametoindex("lo"); + if (!ASSERT_GT(qdisc_hook.ifindex, 0, "if_nametoindex lo")) + goto fail; + + err = crypto_sanity__attach(skel); + if (!ASSERT_OK(err, "crypto_sanity__attach")) + goto fail; + + pfd = bpf_program__fd(skel->progs.crypto_release); + if (!ASSERT_GT(pfd, 0, "crypto_release fd")) + goto fail; + + err = bpf_prog_test_run_opts(pfd, &opts); + if (!ASSERT_OK(err, "crypto_release") || + !ASSERT_OK(opts.retval, "crypto_release retval")) + goto fail; + + pfd = bpf_program__fd(skel->progs.skb_crypto_setup); + if (!ASSERT_GT(pfd, 0, "skb_crypto_setup fd")) + goto fail; + + err = bpf_prog_test_run_opts(pfd, &opts); + if (!ASSERT_OK(err, "skb_crypto_setup") || + !ASSERT_OK(opts.retval, "skb_crypto_setup retval")) + goto fail; + + if (!ASSERT_OK(skel->bss->status, "skb_crypto_setup status")) + goto fail; + + err = bpf_tc_hook_create(&qdisc_hook); + if (!ASSERT_OK(err, "create qdisc hook")) + goto fail; + + addrlen = sizeof(addr); + err = make_sockaddr(AF_INET6, IPV6_IFACE_ADDR, UDP_TEST_PORT, + (void *)&addr, &addrlen); + if (!ASSERT_OK(err, "make_sockaddr")) + goto fail; + + tc_attach_enc.prog_fd = bpf_program__fd(skel->progs.encrypt_sanity); + err = bpf_tc_attach(&qdisc_hook, &tc_attach_enc); + if (!ASSERT_OK(err, "attach encrypt filter")) + goto fail; + + sockfd = socket(AF_INET6, SOCK_DGRAM, 0); + if (!ASSERT_NEQ(sockfd, -1, "encrypt socket")) + goto fail; + err = sendto(sockfd, plain_text, 16, 0, (void *)&addr, addrlen); + close(sockfd); + if (!ASSERT_EQ(err, 16, "encrypt send")) + goto fail; + + do_crypt_afalg(plain_text, afalg_dst, 16, true); + + bpf_tc_detach(&qdisc_hook, &tc_attach_enc); + if (!ASSERT_OK(skel->bss->status, "encrypt status")) + goto fail; + if (!ASSERT_STRNEQ(skel->bss->dst, afalg_dst, sizeof(afalg_dst), "encrypt AF_ALG")) + goto fail; + + tc_attach_dec.prog_fd = bpf_program__fd(skel->progs.decrypt_sanity); + err = bpf_tc_attach(&qdisc_hook, &tc_attach_dec); + if (!ASSERT_OK(err, "attach decrypt filter")) + goto fail; + + sockfd = socket(AF_INET6, SOCK_DGRAM, 0); + if (!ASSERT_NEQ(sockfd, -1, "decrypt socket")) + goto fail; + err = sendto(sockfd, afalg_dst, 16, 0, (void *)&addr, addrlen); + close(sockfd); + if (!ASSERT_EQ(err, 16, "decrypt send")) + goto fail; + + do_crypt_afalg(afalg_dst, afalg_plain, 16, false); + + bpf_tc_detach(&qdisc_hook, &tc_attach_dec); + if (!ASSERT_OK(skel->bss->status, "decrypt status")) + goto fail; + if (!ASSERT_STRNEQ(skel->bss->dst, afalg_plain, sizeof(afalg_plain), "decrypt AF_ALG")) + goto fail; + +fail: + if (nstoken) { + bpf_tc_hook_destroy(&qdisc_hook); + close_netns(nstoken); + } + deinit_afalg(); + SYS_NOFAIL("ip netns del " NS_TEST " &> /dev/null"); + crypto_sanity__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/crypto_common.h b/tools/testing/selftests/bpf/progs/crypto_common.h new file mode 100644 index 000000000000..260b9a0fb4ed --- /dev/null +++ b/tools/testing/selftests/bpf/progs/crypto_common.h @@ -0,0 +1,67 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#ifndef _CRYPTO_COMMON_H +#define _CRYPTO_COMMON_H + +#include "errno.h" +#include + +struct bpf_crypto_ctx *bpf_crypto_ctx_create(const char *type__str, const char *algo__str, + const struct bpf_dynptr *pkey, + unsigned int authsize, int *err) __ksym; +struct bpf_crypto_ctx *bpf_crypto_ctx_acquire(struct bpf_crypto_ctx *ctx) __ksym; +void bpf_crypto_ctx_release(struct bpf_crypto_ctx *ctx) __ksym; +int bpf_crypto_encrypt(struct bpf_crypto_ctx *ctx, const struct bpf_dynptr *src, + struct bpf_dynptr *dst, struct bpf_dynptr *iv) __ksym; +int bpf_crypto_decrypt(struct bpf_crypto_ctx *ctx, const struct bpf_dynptr *src, + struct bpf_dynptr *dst, struct bpf_dynptr *iv) __ksym; + +struct __crypto_ctx_value { + struct bpf_crypto_ctx __kptr * ctx; +}; + +struct array_map { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, int); + __type(value, struct __crypto_ctx_value); + __uint(max_entries, 1); +} __crypto_ctx_map SEC(".maps"); + +static inline struct __crypto_ctx_value *crypto_ctx_value_lookup(void) +{ + u32 key = 0; + + return bpf_map_lookup_elem(&__crypto_ctx_map, &key); +} + +static inline int crypto_ctx_insert(struct bpf_crypto_ctx *ctx) +{ + struct __crypto_ctx_value local, *v; + struct bpf_crypto_ctx *old; + u32 key = 0; + int err; + + local.ctx = NULL; + err = bpf_map_update_elem(&__crypto_ctx_map, &key, &local, 0); + if (err) { + bpf_crypto_ctx_release(ctx); + return err; + } + + v = bpf_map_lookup_elem(&__crypto_ctx_map, &key); + if (!v) { + bpf_crypto_ctx_release(ctx); + return -ENOENT; + } + + old = bpf_kptr_xchg(&v->ctx, ctx); + if (old) { + bpf_crypto_ctx_release(old); + return -EEXIST; + } + + return 0; +} + +#endif /* _CRYPTO_COMMON_H */ diff --git a/tools/testing/selftests/bpf/progs/crypto_sanity.c b/tools/testing/selftests/bpf/progs/crypto_sanity.c new file mode 100644 index 000000000000..f566ff189b7e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/crypto_sanity.c @@ -0,0 +1,192 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include "vmlinux.h" +#include "bpf_tracing_net.h" +#include +#include +#include +#include "bpf_misc.h" +#include "bpf_kfuncs.h" +#include "crypto_common.h" + +#define UDP_TEST_PORT 7777 +unsigned char crypto_key[16] = "testtest12345678"; +char dst[32] = {}; +int status; + +static int skb_dynptr_validate(struct __sk_buff *skb, struct bpf_dynptr *psrc) +{ + struct ipv6hdr ip6h; + struct udphdr udph; + u32 offset; + + if (skb->protocol != __bpf_constant_htons(ETH_P_IPV6)) + return -1; + + if (bpf_skb_load_bytes(skb, ETH_HLEN, &ip6h, sizeof(ip6h))) + return -1; + + if (ip6h.nexthdr != IPPROTO_UDP) + return -1; + + if (bpf_skb_load_bytes(skb, ETH_HLEN + sizeof(ip6h), &udph, sizeof(udph))) + return -1; + + if (udph.dest != __bpf_constant_htons(UDP_TEST_PORT)) + return -1; + + offset = ETH_HLEN + sizeof(ip6h) + sizeof(udph); + if (skb->len < offset + 16) + return -1; + + bpf_dynptr_from_skb(skb, 0, psrc); + bpf_dynptr_adjust(psrc, offset, offset + 16); + + return 0; +} + +SEC("fentry.s/bpf_fentry_test1") +int BPF_PROG(skb_crypto_setup) +{ + struct bpf_crypto_ctx *cctx; + struct bpf_dynptr key = {}; + int err = 0; + + status = 0; + + bpf_dynptr_from_mem(crypto_key, sizeof(crypto_key), 0, &key); + cctx = bpf_crypto_ctx_create("skcipher", "ecb(aes)", &key, 0, &err); + + if (!cctx) { + status = err; + return 0; + } + + err = crypto_ctx_insert(cctx); + if (err && err != -EEXIST) + status = err; + + return 0; +} + +SEC("fentry.s/bpf_fentry_test1") +int BPF_PROG(crypto_release) +{ + struct bpf_crypto_ctx *cctx; + struct bpf_dynptr key = {}; + int err = 0; + + status = 0; + + bpf_dynptr_from_mem(crypto_key, sizeof(crypto_key), 0, &key); + cctx = bpf_crypto_ctx_create("skcipher", "ecb(aes)", &key, 0, &err); + + if (!cctx) { + status = err; + return 0; + } + + bpf_crypto_ctx_release(cctx); + + return 0; +} + +SEC("?fentry.s/bpf_fentry_test1") +__failure __msg("Unreleased reference") +int BPF_PROG(crypto_accuire) +{ + struct bpf_crypto_ctx *cctx; + struct bpf_dynptr key = {}; + int err = 0; + + status = 0; + + bpf_dynptr_from_mem(crypto_key, sizeof(crypto_key), 0, &key); + cctx = bpf_crypto_ctx_create("skcipher", "ecb(aes)", &key, 0, &err); + + if (!cctx) { + status = err; + return 0; + } + + cctx = bpf_crypto_ctx_acquire(cctx); + if (!cctx) + return -EINVAL; + + bpf_crypto_ctx_release(cctx); + + return 0; +} + +SEC("tc") +int decrypt_sanity(struct __sk_buff *skb) +{ + struct __crypto_ctx_value *v; + struct bpf_crypto_ctx *ctx; + struct bpf_dynptr psrc, pdst, iv; + int err; + + err = skb_dynptr_validate(skb, &psrc); + if (err < 0) { + status = err; + return TC_ACT_SHOT; + } + + v = crypto_ctx_value_lookup(); + if (!v) { + status = -ENOENT; + return TC_ACT_SHOT; + } + + ctx = v->ctx; + if (!ctx) { + status = -ENOENT; + return TC_ACT_SHOT; + } + + bpf_dynptr_from_mem(dst, sizeof(dst), 0, &pdst); + bpf_dynptr_from_mem(dst, 0, 0, &iv); + + status = bpf_crypto_decrypt(ctx, &psrc, &pdst, &iv); + + return TC_ACT_SHOT; +} + +SEC("tc") +int encrypt_sanity(struct __sk_buff *skb) +{ + struct __crypto_ctx_value *v; + struct bpf_crypto_ctx *ctx; + struct bpf_dynptr psrc, pdst, iv; + int err; + + status = 0; + + err = skb_dynptr_validate(skb, &psrc); + if (err < 0) { + status = err; + return TC_ACT_SHOT; + } + + v = crypto_ctx_value_lookup(); + if (!v) { + status = -ENOENT; + return TC_ACT_SHOT; + } + + ctx = v->ctx; + if (!ctx) { + status = -ENOENT; + return TC_ACT_SHOT; + } + + bpf_dynptr_from_mem(dst, sizeof(dst), 0, &pdst); + bpf_dynptr_from_mem(dst, 0, 0, &iv); + + status = bpf_crypto_encrypt(ctx, &psrc, &pdst, &iv); + + return TC_ACT_SHOT; +} + +char __license[] SEC("license") = "GPL";