From patchwork Tue Jan 11 18:03:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710277 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3F42C43217 for ; Tue, 11 Jan 2022 18:04:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350072AbiAKSED (ORCPT ); Tue, 11 Jan 2022 13:04:03 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4389 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345158AbiAKSDv (ORCPT ); Tue, 11 Jan 2022 13:03:51 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPq0CrVz67cQc; Wed, 12 Jan 2022 02:00:15 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:47 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 01/14] mpi: Introduce mpi_key_length() Date: Tue, 11 Jan 2022 19:03:05 +0100 Message-ID: <20220111180318.591029-2-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Introduce the new function to get the number of bits and bytes from an MPI. Signed-off-by: Roberto Sassu --- include/linux/mpi.h | 2 ++ lib/mpi/mpicoder.c | 33 ++++++++++++++++++++++++++------- 2 files changed, 28 insertions(+), 7 deletions(-) diff --git a/include/linux/mpi.h b/include/linux/mpi.h index eb0d1c1db208..a7dd4c9d8120 100644 --- a/include/linux/mpi.h +++ b/include/linux/mpi.h @@ -90,6 +90,8 @@ enum gcry_mpi_format { }; MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes); +int mpi_key_length(const void *xbuffer, unsigned int ret_nread, + unsigned int *nbits_arg, unsigned int *nbytes_arg); MPI mpi_read_from_buffer(const void *buffer, unsigned *ret_nread); int mpi_fromstr(MPI val, const char *str); MPI mpi_scanval(const char *string); diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c index 39c4c6731094..cd10ae9968b7 100644 --- a/lib/mpi/mpicoder.c +++ b/lib/mpi/mpicoder.c @@ -79,22 +79,41 @@ MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes) } EXPORT_SYMBOL_GPL(mpi_read_raw_data); -MPI mpi_read_from_buffer(const void *xbuffer, unsigned *ret_nread) +int mpi_key_length(const void *xbuffer, unsigned int ret_nread, + unsigned int *nbits_arg, unsigned int *nbytes_arg) { const uint8_t *buffer = xbuffer; - unsigned int nbits, nbytes; - MPI val; + unsigned int nbits; - if (*ret_nread < 2) - return ERR_PTR(-EINVAL); + if (ret_nread < 2) + return -EINVAL; nbits = buffer[0] << 8 | buffer[1]; if (nbits > MAX_EXTERN_MPI_BITS) { pr_info("MPI: mpi too large (%u bits)\n", nbits); - return ERR_PTR(-EINVAL); + return -EINVAL; } - nbytes = DIV_ROUND_UP(nbits, 8); + if (nbits_arg) + *nbits_arg = nbits; + if (nbytes_arg) + *nbytes_arg = DIV_ROUND_UP(nbits, 8); + + return 0; +} +EXPORT_SYMBOL_GPL(mpi_key_length); + +MPI mpi_read_from_buffer(const void *xbuffer, unsigned int *ret_nread) +{ + const uint8_t *buffer = xbuffer; + unsigned int nbytes; + MPI val; + int ret; + + ret = mpi_key_length(xbuffer, *ret_nread, NULL, &nbytes); + if (ret < 0) + return ERR_PTR(ret); + if (nbytes + 2 > *ret_nread) { pr_info("MPI: mpi larger than buffer nbytes=%u ret_nread=%u\n", nbytes, *ret_nread); From patchwork Tue Jan 11 18:03:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710280 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9DA5C4332F for ; Tue, 11 Jan 2022 18:04:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350118AbiAKSEF (ORCPT ); Tue, 11 Jan 2022 13:04:05 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4390 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345415AbiAKSDv (ORCPT ); Tue, 11 Jan 2022 13:03:51 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPq5XqSz67k5K; Wed, 12 Jan 2022 02:00:15 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:48 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 02/14] rsa: add parser of raw format Date: Tue, 11 Jan 2022 19:03:06 +0100 Message-ID: <20220111180318.591029-3-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Parse the RSA key with RAW format if the ASN.1 parser returns an error. Signed-off-by: Roberto Sassu --- crypto/rsa.c | 14 +++++-- crypto/rsa_helper.c | 69 +++++++++++++++++++++++++++++++++++ include/crypto/internal/rsa.h | 6 +++ 3 files changed, 85 insertions(+), 4 deletions(-) diff --git a/crypto/rsa.c b/crypto/rsa.c index 4cdbec95d077..ece7bafd6984 100644 --- a/crypto/rsa.c +++ b/crypto/rsa.c @@ -164,8 +164,11 @@ static int rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, rsa_free_mpi_key(mpi_key); ret = rsa_parse_pub_key(&raw_key, key, keylen); - if (ret) - return ret; + if (ret) { + ret = rsa_parse_pub_key_raw(&raw_key, key, keylen); + if (ret) + return ret; + } mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz); if (!mpi_key->e) @@ -198,8 +201,11 @@ static int rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key, rsa_free_mpi_key(mpi_key); ret = rsa_parse_priv_key(&raw_key, key, keylen); - if (ret) - return ret; + if (ret) { + ret = rsa_parse_priv_key_raw(&raw_key, key, keylen); + if (ret) + return ret; + } mpi_key->d = mpi_read_raw_data(raw_key.d, raw_key.d_sz); if (!mpi_key->d) diff --git a/crypto/rsa_helper.c b/crypto/rsa_helper.c index 94266f29049c..fb9443df8f0b 100644 --- a/crypto/rsa_helper.c +++ b/crypto/rsa_helper.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include "rsapubkey.asn1.h" #include "rsaprivkey.asn1.h" @@ -148,6 +149,32 @@ int rsa_get_qinv(void *context, size_t hdrlen, unsigned char tag, return 0; } +typedef int (*rsa_get_func)(void *, size_t, unsigned char, + const void *, size_t); + +static int rsa_parse_key_raw(struct rsa_key *rsa_key, + const void *key, unsigned int key_len, + rsa_get_func *func, int n_func) +{ + unsigned int nbytes, len = key_len; + const void *key_ptr = key; + int ret, i; + + for (i = 0; i < n_func; i++) { + ret = mpi_key_length(key_ptr, len, NULL, &nbytes); + if (ret < 0) + return ret; + + ret = func[i](rsa_key, 0, 0, key_ptr + 2, nbytes); + if (ret < 0) + return ret; + + key_ptr += nbytes + 2; + } + + return (key_ptr == key + key_len) ? 0 : -EINVAL; +} + /** * rsa_parse_pub_key() - decodes the BER encoded buffer and stores in the * provided struct rsa_key, pointers to the raw key as is, @@ -166,6 +193,27 @@ int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key, } EXPORT_SYMBOL_GPL(rsa_parse_pub_key); +/** + * rsa_parse_pub_key_raw() - parse the RAW key and store in the provided struct + * rsa_key, pointers to the raw key as is, so that + * the caller can copy it or MPI parse it, etc. + * + * @rsa_key: struct rsa_key key representation + * @key: key in RAW format + * @key_len: length of key + * + * Return: 0 on success or error code in case of error + */ +int rsa_parse_pub_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len) +{ + rsa_get_func pub_func[] = {rsa_get_n, rsa_get_e}; + + return rsa_parse_key_raw(rsa_key, key, key_len, + pub_func, ARRAY_SIZE(pub_func)); +} +EXPORT_SYMBOL_GPL(rsa_parse_pub_key_raw); + /** * rsa_parse_priv_key() - decodes the BER encoded buffer and stores in the * provided struct rsa_key, pointers to the raw key @@ -184,3 +232,24 @@ int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key, return asn1_ber_decoder(&rsaprivkey_decoder, rsa_key, key, key_len); } EXPORT_SYMBOL_GPL(rsa_parse_priv_key); + +/** + * rsa_parse_priv_key_raw() - parse the RAW key and store in the provided struct + * rsa_key, pointers to the raw key as is, so that + * the caller can copy it or MPI parse it, etc. + * + * @rsa_key: struct rsa_key key representation + * @key: key in RAW format + * @key_len: length of key + * + * Return: 0 on success or error code in case of error + */ +int rsa_parse_priv_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len) +{ + rsa_get_func priv_func[] = {rsa_get_n, rsa_get_e, rsa_get_d}; + + return rsa_parse_key_raw(rsa_key, key, key_len, + priv_func, ARRAY_SIZE(priv_func)); +} +EXPORT_SYMBOL_GPL(rsa_parse_priv_key_raw); diff --git a/include/crypto/internal/rsa.h b/include/crypto/internal/rsa.h index e870133f4b77..7141e806ceea 100644 --- a/include/crypto/internal/rsa.h +++ b/include/crypto/internal/rsa.h @@ -50,8 +50,14 @@ struct rsa_key { int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key, unsigned int key_len); +int rsa_parse_pub_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len); + int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key, unsigned int key_len); +int rsa_parse_priv_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len); + extern struct crypto_template rsa_pkcs1pad_tmpl; #endif From patchwork Tue Jan 11 18:03:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710283 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC3DEC433FE for ; Tue, 11 Jan 2022 18:05:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242888AbiAKSFA (ORCPT ); Tue, 11 Jan 2022 13:05:00 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4391 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345189AbiAKSDw (ORCPT ); Tue, 11 Jan 2022 13:03:52 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPr45rbz67wXw; Wed, 12 Jan 2022 02:00:16 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:49 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 03/14] PGPLIB: PGP definitions (RFC 4880) Date: Tue, 11 Jan 2022 19:03:07 +0100 Message-ID: <20220111180318.591029-4-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide some useful PGP definitions from RFC 4880. These describe details of public key crypto as used by crypto keys for things like signature verification. Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/pgp.h | 206 +++++++++++++++++++++++++++++++++++ 1 file changed, 206 insertions(+) create mode 100644 crypto/asymmetric_keys/pgp.h diff --git a/crypto/asymmetric_keys/pgp.h b/crypto/asymmetric_keys/pgp.h new file mode 100644 index 000000000000..5eb4f4222090 --- /dev/null +++ b/crypto/asymmetric_keys/pgp.h @@ -0,0 +1,206 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* PGP definitions (RFC 4880) + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include + +struct pgp_key_ID { + u8 id[8]; +} __packed; + +struct pgp_time { + u8 time[4]; +} __packed; + +/* + * PGP public-key algorithm identifiers [RFC4880: 9.1] + */ +enum pgp_pubkey_algo { + PGP_PUBKEY_RSA_ENC_OR_SIG = 1, + PGP_PUBKEY_RSA_ENC_ONLY = 2, + PGP_PUBKEY_RSA_SIG_ONLY = 3, + PGP_PUBKEY_ELGAMAL = 16, + PGP_PUBKEY_DSA = 17, + PGP_PUBKEY__LAST +}; + +/* + * PGP symmetric-key algorithm identifiers [RFC4880: 9.2] + */ +enum pgp_symkey_algo { + PGP_SYMKEY_PLAINTEXT = 0, + PGP_SYMKEY_IDEA = 1, + PGP_SYMKEY_3DES = 2, + PGP_SYMKEY_CAST5 = 3, + PGP_SYMKEY_BLOWFISH = 4, + PGP_SYMKEY_AES_128KEY = 7, + PGP_SYMKEY_AES_192KEY = 8, + PGP_SYMKEY_AES_256KEY = 9, + PGP_SYMKEY_TWOFISH_256KEY = 10, +}; + +/* + * PGP compression algorithm identifiers [RFC4880: 9.3] + */ +enum pgp_compr_algo { + PGP_COMPR_UNCOMPRESSED = 0, + PGP_COMPR_ZIP = 1, + PGP_COMPR_ZLIB = 2, + PGP_COMPR_BZIP2 = 3, +}; + +/* + * PGP hash algorithm identifiers [RFC4880: 9.4] + */ +enum pgp_hash_algo { + PGP_HASH_MD5 = 1, + PGP_HASH_SHA1 = 2, + PGP_HASH_RIPE_MD_160 = 3, + PGP_HASH_SHA256 = 8, + PGP_HASH_SHA384 = 9, + PGP_HASH_SHA512 = 10, + PGP_HASH_SHA224 = 11, + PGP_HASH__LAST +}; + +extern const char *const pgp_hash_algorithms[PGP_HASH__LAST]; + +/* + * PGP packet type tags [RFC4880: 4.3]. + */ +enum pgp_packet_tag { + PGP_PKT_RESERVED = 0, + PGP_PKT_PUBKEY_ENC_SESSION_KEY = 1, + PGP_PKT_SIGNATURE = 2, + PGP_PKT_SYMKEY_ENC_SESSION_KEY = 3, + PGP_PKT_ONEPASS_SIGNATURE = 4, + PGP_PKT_SECRET_KEY = 5, + PGP_PKT_PUBLIC_KEY = 6, + PGP_PKT_SECRET_SUBKEY = 7, + PGP_PKT_COMPRESSED_DATA = 8, + PGP_PKT_SYM_ENC_DATA = 9, + PGP_PKT_MARKER = 10, + PGP_PKT_LITERAL_DATA = 11, + PGP_PKT_TRUST = 12, + PGP_PKT_USER_ID = 13, + PGP_PKT_PUBLIC_SUBKEY = 14, + PGP_PKT_USER_ATTRIBUTE = 17, + PGP_PKT_SYM_ENC_AND_INTEG_DATA = 18, + PGP_PKT_MODIFY_DETECT_CODE = 19, + PGP_PKT_PRIVATE_0 = 60, + PGP_PKT_PRIVATE_3 = 63, + PGP_PKT__HIGHEST = 63 +}; + +/* + * Signature (tag 2) packet [RFC4880: 5.2]. + */ +enum pgp_signature_version { + PGP_SIG_VERSION_3 = 3, + PGP_SIG_VERSION_4 = 4, +}; + +enum pgp_signature_type { + PGP_SIG_BINARY_DOCUMENT_SIG = 0x00, + PGP_SIG_CANONICAL_TEXT_DOCUMENT_SIG = 0x01, + PGP_SIG_STANDALONE_SIG = 0x02, + PGP_SIG_GENERAL_CERT_OF_UID_PUBKEY = 0x10, + PGP_SIG_PERSONAL_CERT_OF_UID_PUBKEY = 0x11, + PGP_SIG_CASUAL_CERT_OF_UID_PUBKEY = 0x12, + PGP_SIG_POSTITIVE_CERT_OF_UID_PUBKEY = 0x13, + PGP_SIG_SUBKEY_BINDING_SIG = 0x18, + PGP_SIG_PRIMARY_KEY_BINDING_SIG = 0x19, + PGP_SIG_DIRECTLY_ON_KEY = 0x1F, + PGP_SIG_KEY_REVOCATION_SIG = 0x20, + PGP_SIG_SUBKEY_REVOCATION_SIG = 0x28, + PGP_SIG_CERT_REVOCATION_SIG = 0x30, + PGP_SIG_TIMESTAMP_SIG = 0x40, + PGP_SIG_THIRD_PARTY_CONFIRM_SIG = 0x50, +}; + +struct pgp_signature_v3_packet { + enum pgp_signature_version version : 8; /* == PGP_SIG_VERSION_3 */ + u8 length_of_hashed; /* == 5 */ + struct { + enum pgp_signature_type signature_type : 8; + struct pgp_time creation_time; + } __packed hashed; + struct pgp_key_ID issuer; + enum pgp_pubkey_algo pubkey_algo : 8; + enum pgp_hash_algo hash_algo : 8; +} __packed; + +struct pgp_signature_v4_packet { + enum pgp_signature_version version : 8; /* == PGP_SIG_VERSION_4 */ + enum pgp_signature_type signature_type : 8; + enum pgp_pubkey_algo pubkey_algo : 8; + enum pgp_hash_algo hash_algo : 8; +} __packed; + +/* + * V4 signature subpacket types [RFC4880: 5.2.3.1]. + */ +enum pgp_sig_subpkt_type { + PGP_SIG_CREATION_TIME = 2, + PGP_SIG_EXPIRATION_TIME = 3, + PGP_SIG_EXPORTABLE_CERT = 4, + PGP_SIG_TRUST_SIG = 5, + PGP_SIG_REGEXP = 6, + PGP_SIG_REVOCABLE = 7, + PGP_SIG_KEY_EXPIRATION_TIME = 9, + PGP_SIG_PREF_SYM_ALGO = 11, + PGP_SIG_REVOCATION_KEY = 12, + PGP_SIG_ISSUER = 16, + PGP_SIG_NOTATION_DATA = 20, + PGP_SIG_PREF_HASH_ALGO = 21, + PGP_SIG_PREF_COMPR_ALGO = 22, + PGP_SIG_KEY_SERVER_PREFS = 23, + PGP_SIG_PREF_KEY_SERVER = 24, + PGP_SIG_PRIMARY_USER_ID = 25, + PGP_SIG_POLICY_URI = 26, + PGP_SIG_KEY_FLAGS = 27, + PGP_SIG_SIGNERS_USER_ID = 28, + PGP_SIG_REASON_FOR_REVOCATION = 29, + PGP_SIG_FEATURES = 30, + PGP_SIG_TARGET = 31, + PGP_SIG_EMBEDDED_SIG = 32, + PGP_SIG__LAST +}; + +#define PGP_SIG_SUBPKT_TYPE_CRITICAL_MASK 0x80 + +/* + * Key (tag 5, 6, 7 and 14) packet + */ +enum pgp_key_version { + PGP_KEY_VERSION_2 = 2, + PGP_KEY_VERSION_3 = 3, + PGP_KEY_VERSION_4 = 4, +}; + +struct pgp_key_v3_packet { + enum pgp_key_version version : 8; + struct pgp_time creation_time; + u8 expiry[2]; /* 0 or time in days till expiry */ + enum pgp_pubkey_algo pubkey_algo : 8; + u8 key_material[0]; +} __packed; + +struct pgp_key_v4_packet { + enum pgp_key_version version : 8; + struct pgp_time creation_time; + enum pgp_pubkey_algo pubkey_algo : 8; + u8 key_material[0]; +} __packed; + +/* + * Literal Data (tag 11) packet + */ +enum pgp_literal_data_format { + PGP_LIT_FORMAT_BINARY = 0x62, + PGP_LIT_FORMAT_TEXT = 0x74, + PGP_LIT_FORMAT_TEXT_UTF8 = 0x75, +}; From patchwork Tue Jan 11 18:03:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710284 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05484C4332F for ; Tue, 11 Jan 2022 18:05:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350081AbiAKSFA (ORCPT ); Tue, 11 Jan 2022 13:05:00 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4392 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345450AbiAKSDx (ORCPT ); Tue, 11 Jan 2022 13:03:53 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPs2gYKz688S5; Wed, 12 Jan 2022 02:00:17 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:49 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 04/14] PGPLIB: Basic packet parser Date: Tue, 11 Jan 2022 19:03:08 +0100 Message-ID: <20220111180318.591029-5-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide a simple parser that extracts the packets from a PGP packet blob and passes the desirous ones to the given processor function: struct pgp_parse_context { u64 types_of_interest; int (*process_packet)(struct pgp_parse_context *context, enum pgp_packet_tag type, u8 headerlen, const u8 *data, size_t datalen); }; int pgp_parse_packets(const u8 *data, size_t datalen, struct pgp_parse_context *ctx); This is configured on with CONFIG_PGP_LIBRARY. Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/Kconfig | 6 + crypto/asymmetric_keys/Makefile | 5 + crypto/asymmetric_keys/pgp_library.c | 272 +++++++++++++++++++++++++++ crypto/asymmetric_keys/pgplib.h | 33 ++++ 4 files changed, 316 insertions(+) create mode 100644 crypto/asymmetric_keys/pgp_library.c create mode 100644 crypto/asymmetric_keys/pgplib.h diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 1f1f004dc757..0678ede9d17e 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -96,4 +96,10 @@ config SIGNED_PE_FILE_VERIFICATION This option provides support for verifying the signature(s) on a signed PE binary. +config PGP_LIBRARY + tristate "PGP parsing library" + help + This option enables a library that provides a number of simple + utility functions for parsing PGP (RFC 4880) packet-based messages. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index 28b91adba2ae..55a67ebfe8e1 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -86,3 +86,8 @@ tpm_key_parser-y := \ $(obj)/tpm_parser.o: $(obj)/tpm.asn1.h $(obj)/tpm.asn1.o: $(obj)/tpm.asn1.c $(obj)/tpm.asn1.h + +# +# PGP handling +# +obj-$(CONFIG_PGP_LIBRARY) += pgp_library.o diff --git a/crypto/asymmetric_keys/pgp_library.c b/crypto/asymmetric_keys/pgp_library.c new file mode 100644 index 000000000000..d2c3149983d5 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_library.c @@ -0,0 +1,272 @@ +// SPDX-License-Identifier: GPL-2.0 +/* PGP packet parser (RFC 4880) + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PGPL: "fmt +#include +#include +#include + +#include "pgplib.h" + +MODULE_LICENSE("GPL"); + +const char *const pgp_hash_algorithms[PGP_HASH__LAST] = { + [PGP_HASH_MD5] = "md5", + [PGP_HASH_SHA1] = "sha1", + [PGP_HASH_RIPE_MD_160] = "rmd160", + [PGP_HASH_SHA256] = "sha256", + [PGP_HASH_SHA384] = "sha384", + [PGP_HASH_SHA512] = "sha512", + [PGP_HASH_SHA224] = "sha224", +}; +EXPORT_SYMBOL_GPL(pgp_hash_algorithms); + +/** + * pgp_parse_packet_header - Parse a PGP packet header + * @_data: Start of the PGP packet (updated to PGP packet data) + * @_datalen: Amount of data remaining in buffer (decreased) + * @_type: Where the packet type will be returned + * @_headerlen: Where the header length will be returned + * + * Parse a set of PGP packet header [RFC 4880: 4.2]. + * + * Return: packet data size on success; non-zero on error. If successful, + * *_data and *_datalen will have been updated and *_headerlen will be set to + * hold the length of the packet header. + */ +static ssize_t pgp_parse_packet_header(const u8 **_data, size_t *_datalen, + enum pgp_packet_tag *_type, + u8 *_headerlen) +{ + enum pgp_packet_tag type; + const u8 *data = *_data; + size_t size, datalen = *_datalen; + + pr_devel("-->%s(,%zu,,)\n", __func__, datalen); + + if (datalen < 2) + goto short_packet; + + pr_devel("pkthdr %02x, %02x\n", data[0], data[1]); + + type = *data++; + datalen--; + if (!(type & 0x80)) { + pr_debug("Packet type does not have MSB set\n"); + return -EBADMSG; + } + type &= ~0x80; + + if (type & 0x40) { + /* New packet length format */ + type &= ~0x40; + pr_devel("new format: t=%u\n", type); + switch (data[0]) { + case 0x00 ... 0xbf: + /* One-byte length */ + size = data[0]; + data++; + datalen--; + *_headerlen = 2; + break; + case 0xc0 ... 0xdf: + /* Two-byte length */ + if (datalen < 2) + goto short_packet; + size = (data[0] - 192) * 256; + size += data[1] + 192; + data += 2; + datalen -= 2; + *_headerlen = 3; + break; + case 0xff: + /* Five-byte length */ + if (datalen < 5) + goto short_packet; + size = data[1] << 24; + size |= data[2] << 16; + size |= data[3] << 8; + size |= data[4]; + data += 5; + datalen -= 5; + *_headerlen = 6; + break; + default: + pr_debug("Partial body length packet not supported\n"); + return -EBADMSG; + } + } else { + /* Old packet length format */ + u8 length_type = type & 0x03; + + type >>= 2; + pr_devel("old format: t=%u lt=%u\n", type, length_type); + + switch (length_type) { + case 0: + /* One-byte length */ + size = data[0]; + data++; + datalen--; + *_headerlen = 2; + break; + case 1: + /* Two-byte length */ + if (datalen < 2) + goto short_packet; + size = data[0] << 8; + size |= data[1]; + data += 2; + datalen -= 2; + *_headerlen = 3; + break; + case 2: + /* Four-byte length */ + if (datalen < 4) + goto short_packet; + size = data[0] << 24; + size |= data[1] << 16; + size |= data[2] << 8; + size |= data[3]; + data += 4; + datalen -= 4; + *_headerlen = 5; + break; + default: + pr_debug("Indefinite length packet not supported\n"); + return -EBADMSG; + } + } + + pr_devel("datalen=%zu size=%zu\n", datalen, size); + if (datalen < size) + goto short_packet; + if (size > INT_MAX) + goto too_big; + + *_data = data; + *_datalen = datalen; + *_type = type; + pr_devel("Found packet type=%u size=%zd\n", type, size); + return size; + +short_packet: + pr_debug("Attempt to parse short packet\n"); + return -EBADMSG; +too_big: + pr_debug("Signature subpacket size >2G\n"); + return -EMSGSIZE; +} + +/** + * pgp_parse_packets - Parse a set of PGP packets + * @data: Data to be parsed (updated) + * @datalen: Amount of data (updated) + * @ctx: Parsing context + * + * Parse a set of PGP packets [RFC 4880: 4]. + * + * Return: 0 on successful parsing, a negative value otherwise + */ +int pgp_parse_packets(const u8 *data, size_t datalen, + struct pgp_parse_context *ctx) +{ + enum pgp_packet_tag type; + ssize_t pktlen; + u8 headerlen; + int ret; + + while (datalen > 2) { + pktlen = pgp_parse_packet_header(&data, &datalen, &type, + &headerlen); + if (pktlen < 0) + return pktlen; + + if ((ctx->types_of_interest >> type) & 1) { + ret = ctx->process_packet(ctx, type, headerlen, + data, pktlen); + if (ret < 0) + return ret; + } + data += pktlen; + datalen -= pktlen; + } + + if (datalen != 0) { + pr_debug("Excess octets in packet stream\n"); + return -EBADMSG; + } + + return 0; +} +EXPORT_SYMBOL_GPL(pgp_parse_packets); + +/** + * pgp_parse_public_key - Parse the common part of a PGP pubkey packet + * @_data: Content of packet (updated) + * @_datalen: Length of packet remaining (updated) + * @pk: Public key data + * + * Parse the common data struct for a PGP pubkey packet [RFC 4880: 5.5.2]. + * + * Return: 0 on successful parsing, a negative value otherwise + */ +int pgp_parse_public_key(const u8 **_data, size_t *_datalen, + struct pgp_parse_pubkey *pk) +{ + const u8 *data = *_data; + size_t datalen = *_datalen; + unsigned int tmp; + + if (datalen < 12) { + pr_debug("Public key packet too short\n"); + return -EBADMSG; + } + + pk->version = *data++; + switch (pk->version) { + case PGP_KEY_VERSION_2: + case PGP_KEY_VERSION_3: + case PGP_KEY_VERSION_4: + break; + default: + pr_debug("Public key packet with unhandled version %d\n", + pk->version); + return -EBADMSG; + } + + tmp = *data++ << 24; + tmp |= *data++ << 16; + tmp |= *data++ << 8; + tmp |= *data++; + pk->creation_time = tmp; + if (pk->version == PGP_KEY_VERSION_4) { + pk->expires_at = 0; /* Have to get it from the selfsignature */ + } else { + unsigned short ndays; + + ndays = *data++ << 8; + ndays |= *data++; + if (ndays) + pk->expires_at = pk->creation_time + ndays * 86400UL; + else + pk->expires_at = 0; + datalen -= 2; + } + + pk->pubkey_algo = *data++; + datalen -= 6; + + pr_devel("%x,%x,%lx,%lx\n", + pk->version, pk->pubkey_algo, pk->creation_time, + pk->expires_at); + + *_data = data; + *_datalen = datalen; + return 0; +} +EXPORT_SYMBOL_GPL(pgp_parse_public_key); diff --git a/crypto/asymmetric_keys/pgplib.h b/crypto/asymmetric_keys/pgplib.h new file mode 100644 index 000000000000..d82b84179433 --- /dev/null +++ b/crypto/asymmetric_keys/pgplib.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* PGP library definitions (RFC 4880) + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include "pgp.h" + +/* + * PGP library packet parser + */ +struct pgp_parse_context { + u64 types_of_interest; + int (*process_packet)(struct pgp_parse_context *context, + enum pgp_packet_tag type, + u8 headerlen, + const u8 *data, + size_t datalen); +}; + +extern int pgp_parse_packets(const u8 *data, size_t datalen, + struct pgp_parse_context *ctx); + +struct pgp_parse_pubkey { + enum pgp_key_version version : 8; + enum pgp_pubkey_algo pubkey_algo : 8; + __kernel_old_time_t creation_time; + __kernel_old_time_t expires_at; +}; + +extern int pgp_parse_public_key(const u8 **_data, size_t *_datalen, + struct pgp_parse_pubkey *pk); From patchwork Tue Jan 11 18:03:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710289 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7E2AC43219 for ; Tue, 11 Jan 2022 18:06:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345120AbiAKSGb (ORCPT ); Tue, 11 Jan 2022 13:06:31 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4393 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345458AbiAKSDy (ORCPT ); Tue, 11 Jan 2022 13:03:54 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJTw627tz681p5; Wed, 12 Jan 2022 02:03:48 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:50 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 05/14] PGPLIB: Signature parser Date: Tue, 11 Jan 2022 19:03:09 +0100 Message-ID: <20220111180318.591029-6-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide some PGP signature parsing helpers: (1) A function to parse V4 signature subpackets and pass the desired ones to a processor function: int pgp_parse_sig_subpkts(const u8 *data, size_t datalen, struct pgp_parse_sig_context *ctx); (2) A function to parse out basic signature parameters from any PGP signature such that the algorithms and public key can be selected: int pgp_parse_sig_params(const u8 **_data, size_t *_datalen, struct pgp_sig_parameters *p); Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/pgp_library.c | 284 +++++++++++++++++++++++++++ crypto/asymmetric_keys/pgplib.h | 25 +++ 2 files changed, 309 insertions(+) diff --git a/crypto/asymmetric_keys/pgp_library.c b/crypto/asymmetric_keys/pgp_library.c index d2c3149983d5..de4a748db9be 100644 --- a/crypto/asymmetric_keys/pgp_library.c +++ b/crypto/asymmetric_keys/pgp_library.c @@ -270,3 +270,287 @@ int pgp_parse_public_key(const u8 **_data, size_t *_datalen, return 0; } EXPORT_SYMBOL_GPL(pgp_parse_public_key); + +/** + * pgp_parse_sig_subpkt_header - Parse a PGP V4 signature subpacket header + * @_data: Start of the subpacket (updated to subpacket data) + * @_datalen: Amount of data remaining in buffer (decreased) + * @_type: Where the subpacket type will be returned + * + * Parse a PGP V4 signature subpacket header [RFC 4880: 5.2.3.1]. + * + * Return: packet data size on success; non-zero on error. If successful, + * *_data and *_datalen will have been updated and *_headerlen will be set to + * hold the length of the packet header. + */ +static ssize_t pgp_parse_sig_subpkt_header(const u8 **_data, size_t *_datalen, + enum pgp_sig_subpkt_type *_type) +{ + enum pgp_sig_subpkt_type type; + const u8 *data = *_data; + size_t size, datalen = *_datalen; + + pr_devel("-->%s(,%zu,,)\n", __func__, datalen); + + if (datalen < 2) + goto short_subpacket; + + pr_devel("subpkt hdr %02x, %02x\n", data[0], data[1]); + + switch (data[0]) { + case 0x00 ... 0xbf: + /* One-byte length */ + size = data[0]; + data++; + datalen--; + break; + case 0xc0 ... 0xfe: + /* Two-byte length */ + if (datalen < 3) + goto short_subpacket; + size = (data[0] - 192) * 256; + size += data[1] + 192; + data += 2; + datalen -= 2; + break; + case 0xff: + if (datalen < 6) + goto short_subpacket; + size = data[1] << 24; + size |= data[2] << 16; + size |= data[3] << 8; + size |= data[4]; + data += 5; + datalen -= 5; + break; + } + + /* The type octet is included in the size */ + pr_devel("datalen=%zu size=%zu\n", datalen, size); + if (datalen < size) + goto short_subpacket; + if (size == 0) + goto very_short_subpacket; + if (size > INT_MAX) + goto too_big; + + type = *data++ & ~PGP_SIG_SUBPKT_TYPE_CRITICAL_MASK; + datalen--; + size--; + + *_data = data; + *_datalen = datalen; + *_type = type; + pr_devel("Found subpkt type=%u size=%zd\n", type, size); + return size; + +very_short_subpacket: + pr_debug("Signature subpacket size can't be zero\n"); + return -EBADMSG; +short_subpacket: + pr_debug("Attempt to parse short signature subpacket\n"); + return -EBADMSG; +too_big: + pr_debug("Signature subpacket size >2G\n"); + return -EMSGSIZE; +} + +/** + * pgp_parse_sig_subpkts - Parse a set of PGP V4 signatute subpackets + * @data: Data to be parsed (updated) + * @datalen: Amount of data (updated) + * @ctx: Parsing context + * + * Parse a set of PGP signature subpackets [RFC 4880: 5.2.3]. + * + * Return: 0 on successful parsing, an error value otherwise + */ +static int pgp_parse_sig_subpkts(const u8 *data, size_t datalen, + struct pgp_parse_sig_context *ctx) +{ + enum pgp_sig_subpkt_type type; + ssize_t pktlen; + int ret; + + pr_devel("-->%s(,%zu,,)\n", __func__, datalen); + + while (datalen > 2) { + pktlen = pgp_parse_sig_subpkt_header(&data, &datalen, &type); + if (pktlen < 0) + return pktlen; + if (test_bit(type, ctx->types_of_interest)) { + ret = ctx->process_packet(ctx, type, data, pktlen); + if (ret < 0) + return ret; + } + data += pktlen; + datalen -= pktlen; + } + + if (datalen != 0) { + pr_debug("Excess octets in signature subpacket stream\n"); + return -EBADMSG; + } + + return 0; +} + +struct pgp_parse_sig_params_ctx { + struct pgp_parse_sig_context base; + struct pgp_sig_parameters *params; + bool got_the_issuer; +}; + +/* + * Process a V4 signature subpacket. + */ +static int pgp_process_sig_params_subpkt(struct pgp_parse_sig_context *context, + enum pgp_sig_subpkt_type type, + const u8 *data, + size_t datalen) +{ + struct pgp_parse_sig_params_ctx *ctx = + container_of(context, struct pgp_parse_sig_params_ctx, base); + + if (ctx->got_the_issuer) { + pr_debug("V4 signature packet has multiple issuers\n"); + return -EBADMSG; + } + + if (datalen != 8) { + pr_debug("V4 signature issuer subpkt not 8 long (%zu)\n", + datalen); + return -EBADMSG; + } + + memcpy(&ctx->params->issuer, data, 8); + ctx->got_the_issuer = true; + return 0; +} + +/** + * pgp_parse_sig_params - Parse basic parameters from a PGP signature packet + * @_data: Content of packet (updated) + * @_datalen: Length of packet remaining (updated) + * @p: The basic parameters + * + * Parse the basic parameters from a PGP signature packet [RFC 4880: 5.2] that + * are needed to start off a signature verification operation. The only ones + * actually necessary are the signature type (which affects how the data is + * transformed) and the hash algorithm. + * + * We also extract the public key algorithm and the issuer's key ID as we'll + * need those to determine if we actually have the public key available. If + * not, then we can't verify the signature anyway. + * + * Return: 0 if successful or a negative error code. *_data and *_datalen are + * updated to point to the 16-bit subset of the hash value and the set of MPIs. + */ +int pgp_parse_sig_params(const u8 **_data, size_t *_datalen, + struct pgp_sig_parameters *p) +{ + const u8 *data = *_data; + size_t datalen = *_datalen; + int ret; + + pr_devel("-->%s(,%zu,,)\n", __func__, datalen); + + if (datalen < 1) + return -EBADMSG; + p->version = *data; + + if (p->version == PGP_SIG_VERSION_3) { + const struct pgp_signature_v3_packet *v3 = (const void *)data; + + if (datalen < sizeof(*v3)) { + pr_debug("Short V3 signature packet\n"); + return -EBADMSG; + } + datalen -= sizeof(*v3); + data += sizeof(*v3); + + /* V3 has everything we need in the header */ + p->signature_type = v3->hashed.signature_type; + memcpy(&p->issuer, &v3->issuer, 8); + p->pubkey_algo = v3->pubkey_algo; + p->hash_algo = v3->hash_algo; + + } else if (p->version == PGP_SIG_VERSION_4) { + const struct pgp_signature_v4_packet *v4 = (const void *)data; + struct pgp_parse_sig_params_ctx ctx = { + .base.process_packet = pgp_process_sig_params_subpkt, + .params = p, + .got_the_issuer = false, + }; + size_t subdatalen; + + if (datalen < sizeof(*v4) + 2 + 2 + 2) { + pr_debug("Short V4 signature packet\n"); + return -EBADMSG; + } + datalen -= sizeof(*v4); + data += sizeof(*v4); + + /* V4 has most things in the header... */ + p->signature_type = v4->signature_type; + p->pubkey_algo = v4->pubkey_algo; + p->hash_algo = v4->hash_algo; + + /* + * ... but we have to get the key ID from the subpackets, of + * which there are two sets. + */ + __set_bit(PGP_SIG_ISSUER, ctx.base.types_of_interest); + + subdatalen = *data++ << 8; + subdatalen |= *data++; + datalen -= 2; + if (subdatalen) { + /* Hashed subpackets */ + pr_devel("hashed data: %zu (after %zu)\n", + subdatalen, sizeof(*v4)); + if (subdatalen > datalen + 2 + 2) { + pr_debug("Short V4 signature packet [hdata]\n"); + return -EBADMSG; + } + ret = pgp_parse_sig_subpkts(data, subdatalen, + &ctx.base); + if (ret < 0) + return ret; + data += subdatalen; + datalen -= subdatalen; + } + + subdatalen = *data++ << 8; + subdatalen |= *data++; + datalen -= 2; + if (subdatalen) { + /* Unhashed subpackets */ + pr_devel("unhashed data: %zu\n", subdatalen); + if (subdatalen > datalen + 2) { + pr_debug("Short V4 signature packet [udata]\n"); + return -EBADMSG; + } + ret = pgp_parse_sig_subpkts(data, subdatalen, + &ctx.base); + if (ret < 0) + return ret; + data += subdatalen; + datalen -= subdatalen; + } + + if (!ctx.got_the_issuer) { + pr_debug("V4 signature packet lacks issuer\n"); + return -EBADMSG; + } + } else { + pr_debug("Signature packet with unhandled version %d\n", + p->version); + return -EBADMSG; + } + + *_data = data; + *_datalen = datalen; + return 0; +} +EXPORT_SYMBOL_GPL(pgp_parse_sig_params); diff --git a/crypto/asymmetric_keys/pgplib.h b/crypto/asymmetric_keys/pgplib.h index d82b84179433..967e2853186d 100644 --- a/crypto/asymmetric_keys/pgplib.h +++ b/crypto/asymmetric_keys/pgplib.h @@ -31,3 +31,28 @@ struct pgp_parse_pubkey { extern int pgp_parse_public_key(const u8 **_data, size_t *_datalen, struct pgp_parse_pubkey *pk); + +struct pgp_parse_sig_context { + unsigned long types_of_interest[128 / BITS_PER_LONG]; + int (*process_packet)(struct pgp_parse_sig_context *context, + enum pgp_sig_subpkt_type type, + const u8 *data, + size_t datalen); +}; + +extern int pgp_parse_sig_packets(const u8 *data, size_t datalen, + struct pgp_parse_sig_context *ctx); + +struct pgp_sig_parameters { + enum pgp_signature_version version : 8; + enum pgp_signature_type signature_type : 8; + enum pgp_pubkey_algo pubkey_algo : 8; + enum pgp_hash_algo hash_algo : 8; + union { + struct pgp_key_ID issuer; + __be32 issuer32[2]; + }; +}; + +extern int pgp_parse_sig_params(const u8 **_data, size_t *_datalen, + struct pgp_sig_parameters *p); From patchwork Tue Jan 11 18:03:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710287 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91B48C43217 for ; Tue, 11 Jan 2022 18:05:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349890AbiAKSFF (ORCPT ); Tue, 11 Jan 2022 13:05:05 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4394 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345480AbiAKSDz (ORCPT ); Tue, 11 Jan 2022 13:03:55 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPv0JVpz6892N; Wed, 12 Jan 2022 02:00:19 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:51 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 06/14] KEYS: PGP data parser Date: Tue, 11 Jan 2022 19:03:10 +0100 Message-ID: <20220111180318.591029-7-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Implement a PGP data parser for the crypto key type to use when instantiating a key. This parser attempts to parse the instantiation data as a PGP packet sequence (RFC 4880) and if it parses okay, attempts to extract a public-key algorithm key or subkey from it. If it finds such a key, it will set up a public_key subtype payload with appropriate handler routines (RSA) and attach it to the key. Thanks to Tetsuo Handa for pointing out some errors. Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/Kconfig | 11 + crypto/asymmetric_keys/Makefile | 4 + crypto/asymmetric_keys/pgp_parser.h | 18 ++ crypto/asymmetric_keys/pgp_public_key.c | 358 ++++++++++++++++++++++++ 4 files changed, 391 insertions(+) create mode 100644 crypto/asymmetric_keys/pgp_parser.h create mode 100644 crypto/asymmetric_keys/pgp_public_key.c diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 0678ede9d17e..7be60ef07ac0 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -102,4 +102,15 @@ config PGP_LIBRARY This option enables a library that provides a number of simple utility functions for parsing PGP (RFC 4880) packet-based messages. +config PGP_KEY_PARSER + tristate "PGP key parser" + depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE + select PGP_LIBRARY + select MD5 # V3 fingerprint generation + select SHA1 # V4 fingerprint generation + help + This option provides support for parsing PGP (RFC 4880) format blobs + for key data and provides the ability to instantiate a crypto key + from a public key packet found inside the blob. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index 55a67ebfe8e1..a68f9a5d1746 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -91,3 +91,7 @@ $(obj)/tpm.asn1.o: $(obj)/tpm.asn1.c $(obj)/tpm.asn1.h # PGP handling # obj-$(CONFIG_PGP_LIBRARY) += pgp_library.o + +obj-$(CONFIG_PGP_KEY_PARSER) += pgp_key_parser.o +pgp_key_parser-y := \ + pgp_public_key.o diff --git a/crypto/asymmetric_keys/pgp_parser.h b/crypto/asymmetric_keys/pgp_parser.h new file mode 100644 index 000000000000..1a560ce32415 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_parser.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* PGP crypto data parser internal definitions + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include "pgplib.h" + +#define kenter(FMT, ...) \ + pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__) +#define kleave(FMT, ...) \ + pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__) + +/* + * pgp_public_key.c + */ +extern const char *pgp_to_public_key_algo[PGP_PUBKEY__LAST]; diff --git a/crypto/asymmetric_keys/pgp_public_key.c b/crypto/asymmetric_keys/pgp_public_key.c new file mode 100644 index 000000000000..2763a53ea378 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_public_key.c @@ -0,0 +1,358 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Instantiate a public key crypto key from PGP format data [RFC 4880] + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PGP: "fmt +#include +#include +#include +#include +#include +#include +#include +#include + +#include "pgp_parser.h" + +#define MAX_MPI 5 +#define KEYCTL_SUPPORTS_ENCDEC \ + (KEYCTL_SUPPORTS_ENCRYPT | KEYCTL_SUPPORTS_DECRYPT) +#define KEYCTL_SUPPORTS_SIGVER (KEYCTL_SUPPORTS_SIGN | KEYCTL_SUPPORTS_VERIFY) + +MODULE_LICENSE("GPL"); + +const char *pgp_to_public_key_algo[PGP_PUBKEY__LAST] = { + [PGP_PUBKEY_RSA_ENC_OR_SIG] = "rsa", + [PGP_PUBKEY_RSA_ENC_ONLY] = "rsa", + [PGP_PUBKEY_RSA_SIG_ONLY] = "rsa", + [PGP_PUBKEY_ELGAMAL] = NULL, + [PGP_PUBKEY_DSA] = NULL, +}; + +static const int pgp_key_algo_p_num_mpi[PGP_PUBKEY__LAST] = { + [PGP_PUBKEY_RSA_ENC_OR_SIG] = 2, + [PGP_PUBKEY_RSA_ENC_ONLY] = 2, + [PGP_PUBKEY_RSA_SIG_ONLY] = 2, + [PGP_PUBKEY_ELGAMAL] = 3, + [PGP_PUBKEY_DSA] = 4, +}; + +static const u8 pgp_public_key_capabilities[PGP_PUBKEY__LAST] = { + [PGP_PUBKEY_RSA_ENC_OR_SIG] = KEYCTL_SUPPORTS_ENCDEC | + KEYCTL_SUPPORTS_SIGVER, + [PGP_PUBKEY_RSA_ENC_ONLY] = KEYCTL_SUPPORTS_ENCDEC, + [PGP_PUBKEY_RSA_SIG_ONLY] = KEYCTL_SUPPORTS_SIGVER, + [PGP_PUBKEY_ELGAMAL] = 0, + [PGP_PUBKEY_DSA] = 0, +}; + +static inline void digest_putc(struct shash_desc *digest, uint8_t ch) +{ + crypto_shash_update(digest, &ch, 1); +} + +struct pgp_key_data_parse_context { + struct pgp_parse_context pgp; + struct public_key *pub; + u8 raw_fingerprint[HASH_MAX_DIGESTSIZE]; + size_t raw_fingerprint_len; +}; + +/* + * Calculate the public key ID (RFC4880 12.2) + */ +static int pgp_calc_pkey_keyid(struct shash_desc *digest, + struct pgp_parse_pubkey *pgp, + struct public_key *pub) +{ + unsigned int nb[MAX_MPI]; + unsigned int nn[MAX_MPI]; + unsigned int n; + size_t keylen = pub->keylen; + u8 *key_ptr = pub->key; + u8 *pp[MAX_MPI]; + u32 a32; + int npkey = pgp_key_algo_p_num_mpi[pgp->pubkey_algo]; + int i, ret; + + kenter(""); + + n = (pgp->version < PGP_KEY_VERSION_4) ? 8 : 6; + for (i = 0; i < npkey; i++) { + ret = mpi_key_length(key_ptr, keylen, nb + i, nn + i); + if (ret < 0) + return ret; + + if (keylen < 2 + nn[i]) + break; + + pp[i] = key_ptr + 2; + key_ptr += 2 + nn[i]; + keylen -= 2 + nn[i]; + n += 2 + nn[i]; + } + + if (keylen != 0) { + pr_debug("excess %zu\n", keylen); + return -EBADMSG; + } + + digest_putc(digest, 0x99); /* ctb */ + digest_putc(digest, n >> 8); /* 16-bit header length */ + digest_putc(digest, n); + digest_putc(digest, pgp->version); + + a32 = pgp->creation_time; + digest_putc(digest, a32 >> 24); + digest_putc(digest, a32 >> 16); + digest_putc(digest, a32 >> 8); + digest_putc(digest, a32 >> 0); + + if (pgp->version < PGP_KEY_VERSION_4) { + u16 a16; + + if (pgp->expires_at) + a16 = (pgp->expires_at - pgp->creation_time) / 86400UL; + else + a16 = 0; + digest_putc(digest, a16 >> 8); + digest_putc(digest, a16 >> 0); + } + + digest_putc(digest, pgp->pubkey_algo); + + for (i = 0; i < npkey; i++) { + digest_putc(digest, nb[i] >> 8); + digest_putc(digest, nb[i]); + crypto_shash_update(digest, pp[i], nn[i]); + } + ret = 0; + + kleave(" = %d", ret); + return ret; +} + +/* + * Calculate the public key ID fingerprint + */ +static int pgp_generate_fingerprint(struct pgp_key_data_parse_context *ctx, + struct pgp_parse_pubkey *pgp, + struct public_key *pub) +{ + struct crypto_shash *tfm; + struct shash_desc *digest; + char fingerprint[HASH_MAX_DIGESTSIZE * 2 + 1] = { 0 }; + size_t offset; + int ret; + + ret = -ENOMEM; + tfm = crypto_alloc_shash(pgp->version < PGP_KEY_VERSION_4 ? + "md5" : "sha1", 0, 0); + if (!tfm) + goto cleanup; + + digest = kmalloc(sizeof(*digest) + crypto_shash_descsize(tfm), + GFP_KERNEL); + if (!digest) + goto cleanup_tfm; + + digest->tfm = tfm; + crypto_shash_set_flags(digest->tfm, CRYPTO_TFM_REQ_MAY_SLEEP); + ret = crypto_shash_init(digest); + if (ret < 0) + goto cleanup_hash; + + ret = pgp_calc_pkey_keyid(digest, pgp, pub); + if (ret < 0) + goto cleanup_hash; + + ctx->raw_fingerprint_len = crypto_shash_digestsize(tfm); + + ret = crypto_shash_final(digest, ctx->raw_fingerprint); + if (ret < 0) + goto cleanup_hash; + + offset = ctx->raw_fingerprint_len - 8; + pr_debug("offset %lu/%lu\n", offset, ctx->raw_fingerprint_len); + + bin2hex(fingerprint, ctx->raw_fingerprint, ctx->raw_fingerprint_len); + pr_debug("fingerprint %s\n", fingerprint); + + ret = 0; +cleanup_hash: + kfree(digest); +cleanup_tfm: + crypto_free_shash(tfm); +cleanup: + kleave(" = %d", ret); + return ret; +} + +/* + * Extract a public key or public subkey from the PGP stream. + */ +static int pgp_process_public_key(struct pgp_parse_context *context, + enum pgp_packet_tag type, + u8 headerlen, + const u8 *data, + size_t datalen) +{ + const char *algo; + struct pgp_key_data_parse_context *ctx = + container_of(context, struct pgp_key_data_parse_context, pgp); + struct pgp_parse_pubkey pgp; + struct public_key *pub; + u8 capabilities; + int ret; + + kenter(",%u,%u,,%zu", type, headerlen, datalen); + + if (ctx->raw_fingerprint_len) { + kleave(" = -ENOKEY [already]"); + return -EBADMSG; + } + + pub = kzalloc(sizeof(struct public_key), GFP_KERNEL); + if (!pub) + return -ENOMEM; + pub->id_type = "PGP"; + + ret = pgp_parse_public_key(&data, &datalen, &pgp); + if (ret < 0) + goto cleanup; + + if (pgp.pubkey_algo >= PGP_PUBKEY__LAST) + goto cleanup_unsupported_pkey_algo; + algo = pgp_to_public_key_algo[pgp.pubkey_algo]; + if (!algo) + goto cleanup_unsupported_pkey_algo; + + pub->pkey_algo = algo; + + /* + * It's the public half of a key, so that only gives us encrypt and + * verify capabilities. + */ + capabilities = pgp_public_key_capabilities[pgp.pubkey_algo] & + (KEYCTL_SUPPORTS_ENCRYPT | KEYCTL_SUPPORTS_VERIFY); + /* + * Capabilities are not stored anymore in the public key, store only + * those that allow signature verification. + */ + if (!(capabilities & KEYCTL_SUPPORTS_VERIFY)) + goto cleanup_unsupported_pkey_algo; + + pub->key = kmemdup(data, datalen, GFP_KERNEL); + if (!pub->key) + goto cleanup_nomem; + + pub->keylen = datalen; + + ret = pgp_generate_fingerprint(ctx, &pgp, pub); + if (ret < 0) + goto cleanup; + + ctx->pub = pub; + kleave(" = 0 [use]"); + return 0; + +cleanup_unsupported_pkey_algo: + pr_debug("Unsupported public key algorithm %u\n", + pgp.pubkey_algo); + ret = -ENOPKG; + goto cleanup; +cleanup_nomem: + ret = -ENOMEM; + goto cleanup; +cleanup: + pr_devel("cleanup"); + public_key_free(pub); + kleave(" = %d", ret); + return ret; +} + +static struct asymmetric_key_ids *pgp_key_generate_id( + struct pgp_key_data_parse_context *ctx) +{ + struct asymmetric_key_ids *kids; + struct asymmetric_key_id *kid; + + kids = kzalloc(sizeof(struct asymmetric_key_ids), GFP_KERNEL); + if (!kids) + return kids; + + kid = asymmetric_key_generate_id(ctx->raw_fingerprint, + ctx->raw_fingerprint_len, NULL, 0); + if (IS_ERR(kid)) + goto error; + + kids->id[0] = kid; + kids->id[1] = kmemdup(kid, sizeof(*kid) + ctx->raw_fingerprint_len, + GFP_KERNEL); + if (!kids->id[1]) + goto error; + + return kids; +error: + kfree(kids->id[0]); + kfree(kids); + + return NULL; +} + +/* + * Attempt to parse the instantiation data blob for a key as a PGP packet + * message holding a key. + */ +static int pgp_key_parse(struct key_preparsed_payload *prep) +{ + struct pgp_key_data_parse_context ctx; + int ret; + + kenter(""); + + memset(&ctx, 0, sizeof(ctx)); + ctx.pgp.types_of_interest = (1 << PGP_PKT_PUBLIC_KEY); + ctx.pgp.process_packet = pgp_process_public_key; + + ret = pgp_parse_packets(prep->data, prep->datalen, &ctx.pgp); + if (ret < 0) + goto error; + + /* We're pinning the module by being linked against it */ + __module_get(public_key_subtype.owner); + prep->payload.data[asym_subtype] = &public_key_subtype; + prep->payload.data[asym_key_ids] = pgp_key_generate_id(&ctx); + prep->payload.data[asym_crypto] = ctx.pub; + prep->quotalen = 100; + return 0; + +error: + public_key_free(ctx.pub); + return ret; +} + +static struct asymmetric_key_parser pgp_key_parser = { + .owner = THIS_MODULE, + .name = "pgp", + .parse = pgp_key_parse, +}; + +/* + * Module stuff + */ +static int __init pgp_key_init(void) +{ + return register_asymmetric_key_parser(&pgp_key_parser); +} + +static void __exit pgp_key_exit(void) +{ + unregister_asymmetric_key_parser(&pgp_key_parser); +} + +module_init(pgp_key_init); +module_exit(pgp_key_exit); From patchwork Tue Jan 11 18:03:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710285 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A37BFC433F5 for ; Tue, 11 Jan 2022 18:05:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350156AbiAKSFC (ORCPT ); Tue, 11 Jan 2022 13:05:02 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4395 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345494AbiAKSDz (ORCPT ); Tue, 11 Jan 2022 13:03:55 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJQp5x6Vz683S6; Wed, 12 Jan 2022 02:01:06 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:52 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 07/14] KEYS: Provide PGP key description autogeneration Date: Tue, 11 Jan 2022 19:03:11 +0100 Message-ID: <20220111180318.591029-8-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide a facility to autogenerate the name of PGP keys from the contents of the payload. If add_key() is given a blank description, a description is constructed from the last user ID packet in the payload data plus the last 8 hex digits of the key ID. For instance: keyctl padd asymmetric "" @s Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/pgp_public_key.c | 47 ++++++++++++++++++++++++- 1 file changed, 46 insertions(+), 1 deletion(-) diff --git a/crypto/asymmetric_keys/pgp_public_key.c b/crypto/asymmetric_keys/pgp_public_key.c index 2763a53ea378..378ed5ff0a3a 100644 --- a/crypto/asymmetric_keys/pgp_public_key.c +++ b/crypto/asymmetric_keys/pgp_public_key.c @@ -59,6 +59,8 @@ struct pgp_key_data_parse_context { struct public_key *pub; u8 raw_fingerprint[HASH_MAX_DIGESTSIZE]; size_t raw_fingerprint_len; + const char *user_id; + size_t user_id_len; }; /* @@ -210,6 +212,15 @@ static int pgp_process_public_key(struct pgp_parse_context *context, kenter(",%u,%u,,%zu", type, headerlen, datalen); + if (type == PGP_PKT_USER_ID) { + if (!ctx->user_id_len) { + ctx->user_id = data; + ctx->user_id_len = datalen; + } + kleave(" = 0 [user ID]"); + return 0; + } + if (ctx->raw_fingerprint_len) { kleave(" = -ENOKEY [already]"); return -EBADMSG; @@ -315,13 +326,47 @@ static int pgp_key_parse(struct key_preparsed_payload *prep) kenter(""); memset(&ctx, 0, sizeof(ctx)); - ctx.pgp.types_of_interest = (1 << PGP_PKT_PUBLIC_KEY); + ctx.pgp.types_of_interest = (1 << PGP_PKT_PUBLIC_KEY) | + (1 << PGP_PKT_USER_ID); ctx.pgp.process_packet = pgp_process_public_key; ret = pgp_parse_packets(prep->data, prep->datalen, &ctx.pgp); if (ret < 0) goto error; + if (ctx.user_id && ctx.user_id_len > 0) { + /* + * Propose a description for the key (user ID without the + * comment). + */ + size_t ulen = ctx.user_id_len; + const char *p; + + p = memchr(ctx.user_id, '(', ulen); + if (p) { + /* Remove the comment */ + do { + p--; + } while (*p == ' ' && p > ctx.user_id); + if (*p != ' ') + p++; + ulen = p - ctx.user_id; + } + + if (ulen > 255 - 9) + ulen = 255 - 9; + prep->description = kmalloc(ulen + 1 + 8 + 1, GFP_KERNEL); + ret = -ENOMEM; + if (!prep->description) + goto error; + memcpy(prep->description, ctx.user_id, ulen); + prep->description[ulen] = ' '; + bin2hex(prep->description + ulen + 1, + ctx.raw_fingerprint + ctx.raw_fingerprint_len - 4, 4); + prep->description[ulen + 9] = 0; + pr_debug("desc '%s'\n", prep->description); + } + /* We're pinning the module by being linked against it */ __module_get(public_key_subtype.owner); prep->payload.data[asym_subtype] = &public_key_subtype; From patchwork Tue Jan 11 18:03:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710290 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69C11C43217 for ; Tue, 11 Jan 2022 18:06:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345005AbiAKSGa (ORCPT ); Tue, 11 Jan 2022 13:06:30 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4396 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345192AbiAKSD4 (ORCPT ); Tue, 11 Jan 2022 13:03:56 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJTz1xTVz682DK; Wed, 12 Jan 2022 02:03:51 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:53 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 08/14] KEYS: PGP-based public key signature verification Date: Tue, 11 Jan 2022 19:03:12 +0100 Message-ID: <20220111180318.591029-9-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide handlers for PGP-based public-key algorithm signature verification. This does most of the work involved in signature verification as most of it is public-key algorithm agnostic. The public-key verification algorithm itself is just the last little bit and is supplied the complete hash data to process. This requires glue logic putting on top to make use of it - something that the patch introducing verify_pgp_signature() provides. Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- MAINTAINERS | 1 + crypto/asymmetric_keys/Makefile | 3 +- crypto/asymmetric_keys/pgp_signature.c | 507 +++++++++++++++++++++++++ include/crypto/pgp.h | 29 ++ 4 files changed, 539 insertions(+), 1 deletion(-) create mode 100644 crypto/asymmetric_keys/pgp_signature.c create mode 100644 include/crypto/pgp.h diff --git a/MAINTAINERS b/MAINTAINERS index 306de106f31b..844ed460da59 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3025,6 +3025,7 @@ L: keyrings@vger.kernel.org S: Maintained F: Documentation/crypto/asymmetric-keys.rst F: crypto/asymmetric_keys/ +F: include/crypto/pgp.h F: include/crypto/pkcs7.h F: include/crypto/public_key.h F: include/linux/verification.h diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index a68f9a5d1746..e2aeb2a4b6a6 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -94,4 +94,5 @@ obj-$(CONFIG_PGP_LIBRARY) += pgp_library.o obj-$(CONFIG_PGP_KEY_PARSER) += pgp_key_parser.o pgp_key_parser-y := \ - pgp_public_key.o + pgp_public_key.o \ + pgp_signature.o diff --git a/crypto/asymmetric_keys/pgp_signature.c b/crypto/asymmetric_keys/pgp_signature.c new file mode 100644 index 000000000000..4aa71559bcf4 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_signature.c @@ -0,0 +1,507 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* PGP public key signature verification [RFC 4880] + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PGPSIG: "fmt +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "pgp_parser.h" + +static const struct { + enum hash_algo algo : 8; +} pgp_pubkey_hash[PGP_HASH__LAST] = { + [PGP_HASH_MD5].algo = HASH_ALGO_MD5, + [PGP_HASH_SHA1].algo = HASH_ALGO_SHA1, + [PGP_HASH_RIPE_MD_160].algo = HASH_ALGO_RIPE_MD_160, + [PGP_HASH_SHA256].algo = HASH_ALGO_SHA256, + [PGP_HASH_SHA384].algo = HASH_ALGO_SHA384, + [PGP_HASH_SHA512].algo = HASH_ALGO_SHA512, + [PGP_HASH_SHA224].algo = HASH_ALGO_SHA224, +}; + +struct pgp_current_pkt { + enum pgp_packet_tag type; + u8 headerlen; + const u8 *data; + size_t datalen; +}; + +struct pgp_sig_verify { + enum pgp_signature_version sig_version : 8; + struct public_key_signature *sig; + u8 signed_hash_msw[2]; + struct shash_desc *hash; + struct pgp_current_pkt pkt; +}; + +/* + * Find a key in the given keyring by issuer and authority. + */ +static struct key *pgp_request_asymmetric_key(struct pgp_sig_verify *ctx, + struct key *keyring) +{ + struct key *key; + __be32 *issuer32; + char id[12]; + + issuer32 = (__be32 *)ctx->sig->auth_ids[0]->data; + snprintf(id, sizeof(id), "id:%08x%08x", be32_to_cpu(issuer32[0]), + be32_to_cpu(issuer32[1])); + + kenter(",,%s", id); + + pr_debug("Look up key: \"%s\"\n", id); + + key = find_asymmetric_key(keyring, ctx->sig->auth_ids[0], + ctx->sig->auth_ids[1], true); + if (IS_ERR(key)) { + pr_debug("Request for public key '%08x%08x' err %ld\n", + issuer32[0], issuer32[1], PTR_ERR(key)); + + switch (PTR_ERR(key)) { + /* Hide some search errors */ + case -EACCES: + case -ENOTDIR: + case -EAGAIN: + kleave(" = -ENOKEY"); + return ERR_PTR(-ENOKEY); + default: + kleave(" = %ld", PTR_ERR(key)); + return ERR_CAST(key); + } + } + + kleave(" = 0 [%x]", key_serial(key)); + return key; +} + +struct pgp_sig_parse_context { + struct pgp_parse_context pgp; + struct pgp_sig_parameters params; + struct pgp_current_pkt pkt; +}; + +static int pgp_parse_signature(struct pgp_parse_context *context, + enum pgp_packet_tag type, + u8 headerlen, + const u8 *data, + size_t datalen) +{ + struct pgp_sig_parse_context *ctx = + container_of(context, struct pgp_sig_parse_context, pgp); + struct pgp_sig_parameters tmp_params; + struct pgp_current_pkt tmp_pkt = { type, headerlen, data, datalen}; + int ret; + + ret = pgp_parse_sig_params(&data, &datalen, &tmp_params); + if (ret < 0) + return ret; + + if (tmp_params.signature_type != PGP_SIG_BINARY_DOCUMENT_SIG && + tmp_params.signature_type != PGP_SIG_STANDALONE_SIG && + tmp_params.signature_type != PGP_SIG_POSTITIVE_CERT_OF_UID_PUBKEY) + return 0; + + memcpy(&ctx->params, &tmp_params, sizeof(tmp_params)); + memcpy(&ctx->pkt, &tmp_pkt, sizeof(tmp_pkt)); + return 0; +} + +/** + * pgp_sig_parse - Begin the process of verifying a signature + * @sigdata: Signature blob + * @siglen: Length of signature blob + * + * This involves allocating the hash into which first the data and then the + * metadata will be put, and parsing the signature to get the issuer ID from + * which the key used to verify the signature will be searched. + * + * Return: a PGP sig context pointer on success, an error pointer on error + */ +struct pgp_sig_verify *pgp_sig_parse(const u8 *sigdata, size_t siglen) +{ + struct pgp_sig_parse_context p; + struct pgp_sig_verify *ctx; + struct crypto_shash *tfm; + const char *pkey_algo; + size_t digest_size, desc_size; + int ret; + + kenter(",,%zu", siglen); + + p.pgp.types_of_interest = (1 << PGP_PKT_SIGNATURE); + p.pgp.process_packet = pgp_parse_signature; + p.pkt.data = NULL; + ret = pgp_parse_packets(sigdata, siglen, &p.pgp); + if (ret < 0) { + kleave(" = ERR_PTR [bad pkt]"); + return ERR_PTR(ret); + } + + if (!p.pkt.data) { + kleave(" = ERR_PTR [no pkt]"); + return ERR_PTR(-ENOENT); + } + + /* Check the signature itself for usefulness */ + if (p.params.pubkey_algo >= PGP_PUBKEY__LAST) + goto unsupported_pkey_algo; + pkey_algo = pgp_to_public_key_algo[p.params.pubkey_algo]; + if (!pkey_algo) + goto unsupported_pkey_algo; + + if (p.params.hash_algo >= PGP_HASH__LAST || + !pgp_hash_algorithms[p.params.hash_algo]) { + pr_debug("Unsupported hash algorithm %u\n", + p.params.hash_algo); + kleave(" = -ENOPKG [unsupp hash algo]"); + return ERR_PTR(-ENOPKG); + } + + pr_debug("Signature generated with %s hash\n", + pgp_hash_algorithms[p.params.hash_algo]); + + /* Allocate the hashing algorithm we're going to need and find out how + * big the hash operational data will be. + */ + tfm = crypto_alloc_shash(pgp_hash_algorithms[p.params.hash_algo], 0, 0); + if (IS_ERR(tfm)) { + ret = (PTR_ERR(tfm) == -ENOENT ? -ENOPKG : PTR_ERR(tfm)); + kleave(" = %d", ret); + return ERR_PTR(ret); + } + + desc_size = crypto_shash_descsize(tfm); + digest_size = crypto_shash_digestsize(tfm); + + /* We allocate the hash operational data storage on the end of our + * context data. + */ + ctx = kzalloc(sizeof(*ctx) + sizeof(struct shash_desc) + desc_size, + GFP_KERNEL); + if (!ctx) { + ret = -ENOMEM; + goto error_have_shash; + } + + ctx->sig = kzalloc(sizeof(*ctx->sig), GFP_KERNEL); + if (!ctx->sig) { + ret = -ENOMEM; + goto error_have_ctx; + } + + ctx->sig->auth_ids[0] = asymmetric_key_generate_id(p.params.issuer.id, + sizeof(p.params.issuer.id), "", 0); + if (IS_ERR(ctx->sig->auth_ids[0])) { + ret = -ENOMEM; + goto error_have_ctx_sig; + } + + ctx->sig->encoding = "pkcs1"; + ctx->sig->pkey_algo = pkey_algo; + ctx->sig->hash_algo = pgp_hash_algorithms[p.params.hash_algo]; + ctx->sig->digest_size = digest_size; + ctx->hash = (struct shash_desc *)((void *)ctx + + sizeof(*ctx)); + ctx->hash->tfm = tfm; + ctx->sig_version = p.params.version; + + memcpy(&ctx->pkt, &p.pkt, sizeof(p.pkt)); + + ret = crypto_shash_init(ctx->hash); + if (ret < 0) + goto error_have_auth_ids; + + kleave(" = %p", ctx); + return ctx; + +error_have_auth_ids: + kfree(ctx->sig->auth_ids[0]); +error_have_ctx_sig: + kfree(ctx->sig); +error_have_ctx: + kfree(ctx); +error_have_shash: + crypto_free_shash(tfm); + kleave(" = %d", ret); + return ERR_PTR(ret); + +unsupported_pkey_algo: + pr_debug("Unsupported public key algorithm %u\n", + p.params.pubkey_algo); + kleave(" = -ENOPKG [unsupp pk algo]"); + return ERR_PTR(-ENOPKG); +} + +/* + * Load data into the hash + */ +int pgp_sig_add_data(struct pgp_sig_verify *ctx, const void *data, + size_t datalen) +{ + return crypto_shash_update(ctx->hash, data, datalen); +} + +/* + * Extract required metadata from the signature packet and add what we need to + * the hash; finalise the hash. + */ +static int pgp_digest_signature(struct pgp_sig_verify *ctx) +{ + enum pgp_signature_version version; + unsigned int nbytes, nbytes_alloc; + enum pgp_packet_tag type = ctx->pkt.type; + const u8 *data = ctx->pkt.data; + size_t datalen = ctx->pkt.datalen; + int ret; + + kenter(",%u,,%zu", type, datalen); + + if (ctx->sig->digest) { + kleave(" = 0 [digest found]"); + return 0; + } + + version = *data; + if (version == PGP_SIG_VERSION_3) { + /* We just include an excerpt of the metadata from a V3 + * signature. + */ + crypto_shash_update(ctx->hash, data + 2, 5); + data += sizeof(struct pgp_signature_v3_packet); + datalen -= sizeof(struct pgp_signature_v3_packet); + } else if (version == PGP_SIG_VERSION_4) { + /* We add the whole metadata header and some of the hashed data + * for a V4 signature, plus a trailer. + */ + size_t hashedsz, unhashedsz; + u8 trailer[6]; + + hashedsz = 4 + 2 + (data[4] << 8) + data[5]; + crypto_shash_update(ctx->hash, data, hashedsz); + + trailer[0] = version; + trailer[1] = 0xffU; + trailer[2] = hashedsz >> 24; + trailer[3] = hashedsz >> 16; + trailer[4] = hashedsz >> 8; + trailer[5] = hashedsz; + + crypto_shash_update(ctx->hash, trailer, 6); + data += hashedsz; + datalen -= hashedsz; + + unhashedsz = 2 + (data[0] << 8) + data[1]; + data += unhashedsz; + datalen -= unhashedsz; + } + + if (datalen <= 2) { + kleave(" = -EBADMSG"); + return -EBADMSG; + } + + /* There's a quick check on the hash available. */ + ctx->signed_hash_msw[0] = *data++; + ctx->signed_hash_msw[1] = *data++; + datalen -= 2; + + /* And then the cryptographic data, which we'll need for the + * algorithm. + */ + ret = mpi_key_length(data, datalen, NULL, &nbytes); + if (ret < 0) { + kleave(" = -EBADMSG [key length]"); + return ret; + } + + if (datalen != nbytes + 2) { + kleave(" = -EBADMSG [size mismatch]"); + return -EBADMSG; + } + + nbytes_alloc = DIV_ROUND_UP(nbytes, 8) * 8; + + ctx->sig->s = kzalloc(nbytes_alloc, GFP_KERNEL); + if (!ctx->sig->s) { + ret = -ENOMEM; + goto out; + } + + memcpy(ctx->sig->s + nbytes_alloc - nbytes, data + 2, nbytes); + ctx->sig->s_size = nbytes_alloc; + + ctx->sig->digest = kmalloc(ctx->sig->digest_size, GFP_KERNEL); + if (!ctx->sig->digest) { + ret = -ENOMEM; + goto out; + } + + ret = crypto_shash_final(ctx->hash, ctx->sig->digest); + if (ret < 0) + goto out; + + pr_debug("hash: %*phN\n", ctx->sig->digest_size, ctx->sig->digest); +out: + kleave(" = %d", ret); + return ret; +} + +/** + * pgp_sig_get_digest - Finalize digest calculation + * @ctx: PGP sig verification context to use + * @buf: Buffer digest is written to + * @len: Buffer length + * @hash_algo: Digest algorithm + * + * Copy the calculated digest, length and algorithm to the destinations provided + * by the caller. + * + * Return: 0 on success, a negative value on error + */ +int pgp_sig_get_digest(struct pgp_sig_verify *ctx, const u8 **buf, u32 *len, + enum hash_algo *hash_algo) +{ + int ret, i; + + kenter(""); + + ret = pgp_digest_signature(ctx); + if (ret < 0) + goto out; + + i = match_string(hash_algo_name, HASH_ALGO__LAST, + ctx->sig->hash_algo); + if (i < 0) { + ret = -ENOENT; + goto out; + } + + *hash_algo = i; + *buf = ctx->sig->digest; + *len = ctx->sig->digest_size; +out: + kleave(" = %d", ret); + return ret; +} + +/** + * pgp_sig_verify - Verify the PGP signature + * @ctx: PGP sig verification context to use + * @keyring: Keyring containing the key for signature verification + * + * Search the key to be used for signature verification, and verify the PGP + * signature. + * + * Return: 0 if the signature is valid, a negative value otherwise + */ +int pgp_sig_verify(struct pgp_sig_verify *ctx, struct key *keyring) +{ + const struct public_key *pub; + struct key *key; + int ret; + + kenter(""); + + ret = pgp_digest_signature(ctx); + if (ret < 0) + goto out; + + if (ctx->sig->digest[0] != ctx->signed_hash_msw[0] || + ctx->sig->digest[1] != ctx->signed_hash_msw[1]) { + pr_err("Hash (%02x%02x) mismatch against quick check (%02x%02x)\n", + ctx->sig->digest[0], ctx->sig->digest[1], + ctx->signed_hash_msw[0], ctx->signed_hash_msw[1]); + ret = -EKEYREJECTED; + goto out; + } + + /* Now we need to find a key to use */ + key = pgp_request_asymmetric_key(ctx, keyring); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto out; + } + + pub = key->payload.data[asym_crypto]; + + if (strcmp(ctx->sig->pkey_algo, pub->pkey_algo)) { + ret = -EKEYREJECTED; + goto out_key; + } + + ret = verify_signature(key, ctx->sig); +out_key: + key_put(key); +out: + kleave(" = %d", ret); + return ret; +} + +/** + * pgp_sig_verify_cancel - End the PGP signature verification + * @ctx: PGP sig verification context to use + * @keep_sig: Don't deallocate the signature + * + * Free the memory used for the signature verification. + */ +void pgp_sig_verify_cancel(struct pgp_sig_verify *ctx, bool keep_sig) +{ + kenter(""); + + crypto_free_shash(ctx->hash->tfm); + if (!keep_sig) + public_key_signature_free(ctx->sig); + + kfree(ctx); + + kleave(""); +} + +/** + * pgp_sig_get_sig - Return the PGP signature + * @ctx: PGP sig verification context to use + * + * Finalize the signature by calculating the digest if not already done. Then, + * return the PGP signature to the caller. + * + * Return: the PGP signature if successfully finalized, an error pointer + * otherwise + */ +struct public_key_signature *pgp_sig_get_sig(struct pgp_sig_verify *ctx) +{ + int ret; + + ret = pgp_digest_signature(ctx); + if (ret < 0) + return ERR_PTR(-ENOENT); + + return ctx->sig; +} + +/** + * pgp_sig_get_version - Return the PGP signature version + * @ctx: PGP sig verification context to use + * + * Return the version of the PGP signature to the caller. + * + * Return: the PGP signature version + */ +u8 pgp_sig_get_version(struct pgp_sig_verify *ctx) +{ + return ctx->sig_version; +} diff --git a/include/crypto/pgp.h b/include/crypto/pgp.h new file mode 100644 index 000000000000..a58453843dc8 --- /dev/null +++ b/include/crypto/pgp.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* PGP signature processing + * + * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#ifndef _CRYPTO_PGP_H +#define _CRYPTO_PGP_H + +#include + +struct key; +struct pgp_sig_verify; + +/* + * pgp_signature.c + */ +extern struct pgp_sig_verify *pgp_sig_parse(const u8 *sigdata, size_t siglen); +extern int pgp_sig_add_data(struct pgp_sig_verify *ctx, + const void *data, size_t datalen); +extern int pgp_sig_get_digest(struct pgp_sig_verify *ctx, const u8 **buf, + u32 *len, enum hash_algo *hash_algo); +extern int pgp_sig_verify(struct pgp_sig_verify *ctx, struct key *keyring); +extern void pgp_sig_verify_cancel(struct pgp_sig_verify *ctx, bool keep_sig); +extern struct public_key_signature *pgp_sig_get_sig(struct pgp_sig_verify *ctx); +extern u8 pgp_sig_get_version(struct pgp_sig_verify *ctx); + +#endif /* _CRYPTO_PGP_H */ From patchwork Tue Jan 11 18:03:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710279 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04395C4167D for ; Tue, 11 Jan 2022 18:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350134AbiAKSEH (ORCPT ); Tue, 11 Jan 2022 13:04:07 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4397 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345541AbiAKSD5 (ORCPT ); Tue, 11 Jan 2022 13:03:57 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJV00fWQz67ykV; Wed, 12 Jan 2022 02:03:52 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:54 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 09/14] KEYS: Retry asym key search with partial ID in restrict_link_by_signature() Date: Tue, 11 Jan 2022 19:03:13 +0100 Message-ID: <20220111180318.591029-10-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Retry asymmetric key search in restrict_link_by_signature() to support the case of partial IDs, provided by PGP signatures (only the last 8 bytes). Although recently draft-ietf-openpgp-rfc4880bis-10 supports the signature subpacket type 33, which contains the full issuer fingerprint, we cannot rely on existing signatures to support it. Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/restrict.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c index 84cefe3b3585..f1ad1862ee9d 100644 --- a/crypto/asymmetric_keys/restrict.c +++ b/crypto/asymmetric_keys/restrict.c @@ -97,8 +97,14 @@ int restrict_link_by_signature(struct key *dest_keyring, key = find_asymmetric_key(trust_keyring, sig->auth_ids[0], sig->auth_ids[1], false); - if (IS_ERR(key)) - return -ENOKEY; + if (IS_ERR(key)) { + /* Retry with a partial ID. */ + key = find_asymmetric_key(trust_keyring, + sig->auth_ids[0], sig->auth_ids[1], + true); + if (IS_ERR(key)) + return -ENOKEY; + } if (use_builtin_keys && !test_bit(KEY_FLAG_BUILTIN, &key->flags)) ret = -ENOKEY; From patchwork Tue Jan 11 18:03:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710281 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D37DC433F5 for ; Tue, 11 Jan 2022 18:04:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350141AbiAKSEH (ORCPT ); Tue, 11 Jan 2022 13:04:07 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4398 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345554AbiAKSD6 (ORCPT ); Tue, 11 Jan 2022 13:03:58 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJQs1ypdz6842D; Wed, 12 Jan 2022 02:01:09 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:54 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 10/14] KEYS: Calculate key digest and get signature of the key Date: Tue, 11 Jan 2022 19:03:14 +0100 Message-ID: <20220111180318.591029-11-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Calculate the digest of the signature, according to the RFC4880 section 5.2.4, get the last suitable signature with type 0x13 (Positive certification of a User ID and Public Key packet), and store it in the asym_auth field of the key payload, so that it is available for validating a restriction on a keyring. The rationale of taking the last signature is that, if there are multiple signatures, that would be of a different issuer (not a self-signature), that likely has more chances to be useful for the restriction verification. If there is one (the self-signature), that will be used. Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/pgp_public_key.c | 81 +++++++++++++++++++++++++ 1 file changed, 81 insertions(+) diff --git a/crypto/asymmetric_keys/pgp_public_key.c b/crypto/asymmetric_keys/pgp_public_key.c index 378ed5ff0a3a..cecd67bab4e6 100644 --- a/crypto/asymmetric_keys/pgp_public_key.c +++ b/crypto/asymmetric_keys/pgp_public_key.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "pgp_parser.h" @@ -61,6 +62,8 @@ struct pgp_key_data_parse_context { size_t raw_fingerprint_len; const char *user_id; size_t user_id_len; + const char *key_pkt; + size_t key_pkt_len; }; /* @@ -226,6 +229,12 @@ static int pgp_process_public_key(struct pgp_parse_context *context, return -EBADMSG; } + /* Pointer refers to data being processed. */ + if (type == PGP_PKT_PUBLIC_KEY) { + ctx->key_pkt = data; + ctx->key_pkt_len = datalen; + } + pub = kzalloc(sizeof(struct public_key), GFP_KERNEL); if (!pub) return -ENOMEM; @@ -314,6 +323,77 @@ static struct asymmetric_key_ids *pgp_key_generate_id( return NULL; } +/* + * Calculate the digest of the signature according to the RFC4880, section + * 5.2.4 (packet type 0x13). + */ +static int pgp_key_add_sig_data(struct pgp_key_data_parse_context *ctx, + struct pgp_sig_verify *sig_ctx) +{ + loff_t offset = 0; + u8 *data; + + if (!ctx->key_pkt_len || !ctx->user_id_len) + return 0; + + /* 0x99 + key pkt len + key pkt + 0xb4 + user ID len + user ID */ + data = kmalloc(1 + sizeof(u16) + ctx->key_pkt_len + + 1 + sizeof(u32) + ctx->user_id_len, GFP_KERNEL); + if (!data) + return -ENOMEM; + + data[offset++] = 0x99; + data[offset++] = ctx->key_pkt_len >> 8; + data[offset++] = ctx->key_pkt_len; + + memcpy(data + offset, ctx->key_pkt, ctx->key_pkt_len); + offset += ctx->key_pkt_len; + + if (pgp_sig_get_version(sig_ctx) == PGP_SIG_VERSION_4) { + data[offset++] = 0xb4; + data[offset++] = ctx->user_id_len >> 24; + data[offset++] = ctx->user_id_len >> 16; + data[offset++] = ctx->user_id_len >> 8; + data[offset++] = ctx->user_id_len; + } + + memcpy(data + offset, ctx->user_id, ctx->user_id_len); + offset += ctx->user_id_len; + + pgp_sig_add_data(sig_ctx, data, offset); + kfree(data); + return 0; +} + +static struct public_key_signature *pgp_key_get_sig( + struct key_preparsed_payload *prep, + struct pgp_key_data_parse_context *ctx) +{ + struct public_key_signature *sig = NULL; + struct pgp_sig_verify *sig_ctx; + bool keep_sig = false; + int ret; + + sig_ctx = pgp_sig_parse(prep->data, prep->datalen); + if (IS_ERR(sig_ctx)) + return NULL; + + ret = pgp_key_add_sig_data(ctx, sig_ctx); + if (ret < 0) + goto out; + + sig = pgp_sig_get_sig(sig_ctx); + if (IS_ERR(sig)) { + sig = NULL; + goto out; + } + + keep_sig = true; +out: + pgp_sig_verify_cancel(sig_ctx, keep_sig); + return sig; +} + /* * Attempt to parse the instantiation data blob for a key as a PGP packet * message holding a key. @@ -372,6 +452,7 @@ static int pgp_key_parse(struct key_preparsed_payload *prep) prep->payload.data[asym_subtype] = &public_key_subtype; prep->payload.data[asym_key_ids] = pgp_key_generate_id(&ctx); prep->payload.data[asym_crypto] = ctx.pub; + prep->payload.data[asym_auth] = pgp_key_get_sig(prep, &ctx); prep->quotalen = 100; return 0; From patchwork Tue Jan 11 18:03:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710286 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C3B2C4321E for ; Tue, 11 Jan 2022 18:05:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242868AbiAKSFI (ORCPT ); Tue, 11 Jan 2022 13:05:08 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4401 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349792AbiAKSEB (ORCPT ); Tue, 11 Jan 2022 13:04:01 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPz0y9yz688jd; Wed, 12 Jan 2022 02:00:23 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:55 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 11/14] verification: introduce verify_pgp_signature() Date: Tue, 11 Jan 2022 19:03:15 +0100 Message-ID: <20220111180318.591029-12-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Introduce verify_pgp_signature() to verify PGP signatures from detached data. It will be used by fsverity and by IMA. Signed-off-by: Roberto Sassu --- certs/system_keyring.c | 70 ++++++++++++++++++++++++++++++++++++ include/linux/verification.h | 23 ++++++++++++ 2 files changed, 93 insertions(+) diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 692365dee2bd..26a11b1dcd59 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "common.h" static struct key *builtin_trusted_keys; @@ -289,6 +290,75 @@ int verify_pkcs7_signature(const void *data, size_t len, } EXPORT_SYMBOL_GPL(verify_pkcs7_signature); +#ifdef CONFIG_PGP_KEY_PARSER +/** + * verify_pgp_signature - Verify a PGP-based signature on system data. + * @data: The data to be verified (must be provided). + * @len: Size of @data. + * @raw_pgp: The PGP message that is the signature. + * @pgp_len: The size of @raw_pgp. + * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, + * (void *)1UL for all trusted keys). + * @usage: The use to which the key is being put. + * @view_content: Callback to gain access to content. + * @ctx: Context for callback. + */ +int verify_pgp_signature(const void *data, size_t len, + const void *raw_pgp, size_t pgp_len, + struct key *trusted_keys, + enum key_being_used_for usage, + int (*view_content)(void *ctx, + const void *data, size_t len, + size_t asn1hdrlen), + void *ctx) +{ + struct pgp_sig_verify *pgp_ctx; + int ret; + + if (!data || !len) + return -EINVAL; + + pgp_ctx = pgp_sig_parse(raw_pgp, pgp_len); + if (IS_ERR(pgp_ctx)) + return PTR_ERR(pgp_ctx); + + if (!trusted_keys) { + trusted_keys = builtin_trusted_keys; + } else if (trusted_keys == VERIFY_USE_SECONDARY_KEYRING) { +#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING + trusted_keys = secondary_trusted_keys; +#else + trusted_keys = builtin_trusted_keys; +#endif + } else if (trusted_keys == VERIFY_USE_PLATFORM_KEYRING) { +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING + trusted_keys = platform_trusted_keys; +#else + trusted_keys = NULL; +#endif + if (!trusted_keys) { + ret = -ENOKEY; + pr_devel("PGP platform keyring is not available\n"); + goto error; + } + } + + /* The data should be detached - so we need to supply it. */ + if (pgp_sig_add_data(pgp_ctx, data, len)) { + pr_err("Failed to supply data for PGP signature\n"); + ret = -EBADMSG; + goto error; + } + + ret = pgp_sig_verify(pgp_ctx, trusted_keys); +error: + pgp_sig_verify_cancel(pgp_ctx, false); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_pgp_signature); + +#endif /* CONFIG_PGP_KEY_PARSER */ #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING diff --git a/include/linux/verification.h b/include/linux/verification.h index a655923335ae..c27516d68962 100644 --- a/include/linux/verification.h +++ b/include/linux/verification.h @@ -54,6 +54,29 @@ extern int verify_pkcs7_message_sig(const void *data, size_t len, size_t asn1hdrlen), void *ctx); +#ifdef CONFIG_PGP_KEY_PARSER +extern int verify_pgp_signature(const void *data, size_t len, + const void *raw_pgp, size_t pgp_len, + struct key *trusted_keys, + enum key_being_used_for usage, + int (*view_content)(void *ctx, + const void *data, size_t len, + size_t asn1hdrlen), + void *ctx); +#else +static inline int verify_pgp_signature(const void *data, size_t len, + const void *raw_pgp, size_t pgp_len, + struct key *trusted_keys, + enum key_being_used_for usage, + int (*view_content)(void *ctx, + const void *data, size_t len, + size_t asn1hdrlen), + void *ctx) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_PGP_KEY_PARSER */ + #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION extern int verify_pefile_signature(const void *pebuf, unsigned pelen, struct key *trusted_keys, From patchwork Tue Jan 11 18:03:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710288 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 655F6C433EF for ; Tue, 11 Jan 2022 18:05:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345851AbiAKSFJ (ORCPT ); Tue, 11 Jan 2022 13:05:09 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4400 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345691AbiAKSEB (ORCPT ); Tue, 11 Jan 2022 13:04:01 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPz6dnDz688Cb; Wed, 12 Jan 2022 02:00:23 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:56 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 12/14] PGP: Provide a key type for testing PGP signatures Date: Tue, 11 Jan 2022 19:03:16 +0100 Message-ID: <20220111180318.591029-13-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide a key type for testing the PGP signature parser. It is given a non-detached PGP message as payload: keyctl padd pgp_test a @s content.txt gpg --compress-algo=none -s content.txt Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/Kconfig | 13 +++ crypto/asymmetric_keys/Makefile | 2 + crypto/asymmetric_keys/pgp_library.c | 64 +++++++++++++ crypto/asymmetric_keys/pgp_test_key.c | 129 ++++++++++++++++++++++++++ crypto/asymmetric_keys/pgplib.h | 16 ++++ 5 files changed, 224 insertions(+) create mode 100644 crypto/asymmetric_keys/pgp_test_key.c diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 7be60ef07ac0..5f328f57dd0b 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -113,4 +113,17 @@ config PGP_KEY_PARSER for key data and provides the ability to instantiate a crypto key from a public key packet found inside the blob. +config PGP_TEST_KEY + tristate "PGP testing key type" + depends on SYSTEM_DATA_VERIFICATION + depends on PGP_KEY_PARSER=y + help + This option provides a type of key that can be loaded up from a + PGP message - provided the message is signed by a trusted key. If + it is, the PGP wrapper is discarded and reading the key returns + just the payload. If it isn't, adding the key will fail with an + error. + + This is intended for testing the PGP parser. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index e2aeb2a4b6a6..99240d11f591 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -96,3 +96,5 @@ obj-$(CONFIG_PGP_KEY_PARSER) += pgp_key_parser.o pgp_key_parser-y := \ pgp_public_key.o \ pgp_signature.o + +obj-$(CONFIG_PGP_TEST_KEY) += pgp_test_key.o diff --git a/crypto/asymmetric_keys/pgp_library.c b/crypto/asymmetric_keys/pgp_library.c index de4a748db9be..5e5d75e99194 100644 --- a/crypto/asymmetric_keys/pgp_library.c +++ b/crypto/asymmetric_keys/pgp_library.c @@ -554,3 +554,67 @@ int pgp_parse_sig_params(const u8 **_data, size_t *_datalen, return 0; } EXPORT_SYMBOL_GPL(pgp_parse_sig_params); + +#if IS_ENABLED(CONFIG_PGP_TEST_KEY) + +/** + * pgp_parse_literal_data - Parse basic params from a PGP literal data packet + * @data: Content of packet + * @datalen: Length of packet remaining + * @p: The basic parameters + * + * Parse the basic parameters from a PGP literal data packet [RFC 4880: 5.9] + * that are needed to work out what form the data is in and where it is. + * + * Returns 0 if successful or a negative error code. + */ +int pgp_parse_literal_data(const u8 *data, size_t datalen, + struct pgp_literal_data_parameters *p) +{ + unsigned int tmp; + + pr_devel("-->%s(,%zu,,)\n", __func__, datalen); + + if (datalen < 6) + goto too_short; + datalen -= 6; + + p->format = *data++; + switch (p->format) { + case PGP_LIT_FORMAT_BINARY: + case PGP_LIT_FORMAT_TEXT: + case PGP_LIT_FORMAT_TEXT_UTF8: + break; + default: + pr_debug("Literal data packet with unhandled format %02x\n", + p->format); + return -EBADMSG; + } + + p->filename_len = *data++; + p->filename_offset = 2; + if (datalen < p->filename_len) + goto too_short; + data += p->filename_len; + datalen -= p->filename_len; + + tmp = *data++ << 24; + tmp |= *data++ << 16; + tmp |= *data++ << 8; + tmp |= *data++; + p->time = tmp; + + p->content_offset = 6 + p->filename_len; + p->content_len = datalen; + + pr_devel("%x,%u,%x,%u\n", + p->format, p->filename_len, p->time, p->content_len); + return 0; + +too_short: + pr_debug("Literal data packet too short\n"); + return -EBADMSG; +} +EXPORT_SYMBOL_GPL(pgp_parse_literal_data); + +#endif /* CONFIG_PGP_TEST_KEY */ diff --git a/crypto/asymmetric_keys/pgp_test_key.c b/crypto/asymmetric_keys/pgp_test_key.c new file mode 100644 index 000000000000..e067dedf6ca0 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_test_key.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Testing module to load key from trusted PGP message + * + * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PGPtest: "fmt +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "pgp_parser.h" + +MODULE_LICENSE("GPL"); + +struct pgp_test_parse_context { + struct pgp_parse_context pgp; + struct pgp_literal_data_parameters params; + const void *content; +}; + +static int pgp_test_parse_data(struct pgp_parse_context *context, + enum pgp_packet_tag type, + u8 headerlen, + const u8 *data, + size_t datalen) +{ + struct pgp_test_parse_context *ctx = + container_of(context, struct pgp_test_parse_context, pgp); + int ret; + + kenter(""); + + ret = pgp_parse_literal_data(data, datalen, &ctx->params); + if (ret == 0) + ctx->content = data + ctx->params.content_offset; + return ret; +} + +/* + * Instantiate a PGP wrapped and validated key. + */ +static int pgp_test_instantiate(struct key *key, + struct key_preparsed_payload *prep) +{ + struct pgp_test_parse_context p; + const void *saved_prep_data; + size_t saved_prep_datalen; + const struct cred *cred = current_cred(); + int ret; + + kenter(""); + + memset(&p, 0, sizeof(p)); + p.pgp.types_of_interest = (1 << PGP_PKT_LITERAL_DATA); + p.pgp.process_packet = pgp_test_parse_data; + ret = pgp_parse_packets(prep->data, prep->datalen, &p.pgp); + if (ret < 0) { + kleave(" = %d [parse]", ret); + return ret; + } + + if (!p.params.content_len) { + kleave(" = -ENODATA [no literal data"); + return -ENODATA; + } + + ret = verify_pgp_signature(p.content, p.params.content_len, + prep->data, prep->datalen, NULL, + VERIFYING_UNSPECIFIED_SIGNATURE, NULL, NULL); + if (ret < 0 && cred->session_keyring) { + ret = verify_pgp_signature(p.content, p.params.content_len, + prep->data, prep->datalen, + cred->session_keyring, + VERIFYING_UNSPECIFIED_SIGNATURE, + NULL, NULL); + if (ret < 0) + goto error; + + pr_warn("PGP message doesn't chain back to a trusted key\n"); + } + + saved_prep_data = prep->data; + saved_prep_datalen = prep->datalen; + prep->data = p.content; + prep->datalen = p.params.content_len; + ret = generic_key_instantiate(key, prep); + prep->data = saved_prep_data; + prep->datalen = saved_prep_datalen; +error: + kleave(" = %d", ret); + return ret; +} + +/* + * user defined keys take an arbitrary string as the description and an + * arbitrary blob of data as the payload + */ +static struct key_type key_type_pgp_test = { + .name = "pgp_test", + .instantiate = pgp_test_instantiate, + .revoke = user_revoke, + .destroy = user_destroy, + .describe = user_describe, + .read = user_read, +}; + +/* + * Module stuff + */ +static int __init pgp_key_init(void) +{ + return register_key_type(&key_type_pgp_test); +} + +static void __exit pgp_key_cleanup(void) +{ + unregister_key_type(&key_type_pgp_test); +} + +module_init(pgp_key_init); +module_exit(pgp_key_cleanup); diff --git a/crypto/asymmetric_keys/pgplib.h b/crypto/asymmetric_keys/pgplib.h index 967e2853186d..0dc3cd142469 100644 --- a/crypto/asymmetric_keys/pgplib.h +++ b/crypto/asymmetric_keys/pgplib.h @@ -56,3 +56,19 @@ struct pgp_sig_parameters { extern int pgp_parse_sig_params(const u8 **_data, size_t *_datalen, struct pgp_sig_parameters *p); + +#if IS_ENABLED(CONFIG_PGP_TEST_KEY) + +struct pgp_literal_data_parameters { + enum pgp_literal_data_format format : 8; + u8 filename_len; + u8 filename_offset; + u8 content_offset; + u32 content_len; + u32 time; +}; + +extern int pgp_parse_literal_data(const u8 *data, size_t datalen, + struct pgp_literal_data_parameters *p); + +#endif /* CONFIG_PGP_TEST_KEY */ From patchwork Tue Jan 11 18:03:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710282 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64EC0C4167D for ; Tue, 11 Jan 2022 18:04:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350197AbiAKSEX (ORCPT ); Tue, 11 Jan 2022 13:04:23 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4399 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345640AbiAKSEA (ORCPT ); Tue, 11 Jan 2022 13:04:00 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJQv55hlz67x8s; Wed, 12 Jan 2022 02:01:11 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:57 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 13/14] KEYS: Provide a function to load keys from a PGP keyring blob Date: Tue, 11 Jan 2022 19:03:17 +0100 Message-ID: <20220111180318.591029-14-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: David Howells Provide a function to load keys from a PGP keyring blob to the built-in keyring: int preload_pgp_keys(const u8 *pgpdata, size_t pgpdatalen, struct key *keyring); Descriptions are generated from user ID notes and key fingerprints. The keys will actually be identified by the ID calculated from the PGP data rather than by the description, so this shouldn't be a problem. The keys are attached to the keyring supplied. Looking as root in /proc/keys after the built-in keyring has been loaded: 383a00c1 I------ 1 perm 1f030000 0 0 asymmetri \ Red Hat, Inc. dbeca166: PGP.DSA dbeca166 [] Thanks to Tetsuo Handa for some pointing out some errors. Signed-off-by: David Howells Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu --- crypto/asymmetric_keys/Kconfig | 8 ++ crypto/asymmetric_keys/Makefile | 1 + crypto/asymmetric_keys/pgp_preload.c | 110 +++++++++++++++++++++++++++ include/crypto/pgp.h | 8 +- 4 files changed, 126 insertions(+), 1 deletion(-) create mode 100644 crypto/asymmetric_keys/pgp_preload.c diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 5f328f57dd0b..79a95bf8919a 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -126,4 +126,12 @@ config PGP_TEST_KEY This is intended for testing the PGP parser. +config PGP_PRELOAD + bool "PGP public key preloading facility" + depends on SYSTEM_TRUSTED_KEYRING + select PGP_KEY_PARSER + help + This option provides a facility for the kernel to preload PGP-wrapped + bundles of keys during boot to the built-in keyring. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index 99240d11f591..daaed990376f 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -91,6 +91,7 @@ $(obj)/tpm.asn1.o: $(obj)/tpm.asn1.c $(obj)/tpm.asn1.h # PGP handling # obj-$(CONFIG_PGP_LIBRARY) += pgp_library.o +obj-$(CONFIG_PGP_PRELOAD) += pgp_preload.o obj-$(CONFIG_PGP_KEY_PARSER) += pgp_key_parser.o pgp_key_parser-y := \ diff --git a/crypto/asymmetric_keys/pgp_preload.c b/crypto/asymmetric_keys/pgp_preload.c new file mode 100644 index 000000000000..0eb9ba0db3df --- /dev/null +++ b/crypto/asymmetric_keys/pgp_preload.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Asymmetric key request handling + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include +#include +#include + +#include "pgp_parser.h" + +struct preload_pgp_keys_context { + struct pgp_parse_context pgp; + key_ref_t keyring; + const u8 *key_start; + const u8 *key_end; + bool found_key; +}; + +/* + * Create a key. + */ +static void __init create_pgp_key(struct preload_pgp_keys_context *ctx) +{ + key_ref_t key; + + key = key_create_or_update(ctx->keyring, + "asymmetric", + NULL, + ctx->key_start, + ctx->key_end - ctx->key_start, + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA | + KEY_ALLOC_BUILT_IN | + KEY_ALLOC_BYPASS_RESTRICTION); + if (IS_ERR(key)) { + pr_notice("Ignoring PGP key, error: %ld\n", PTR_ERR(key)); + return; + } + + pr_notice("Loaded PGP key '%s'\n", + key_ref_to_ptr(key)->description); + + key_ref_put(key); +} + +/* + * Extract a public key or subkey from the PGP stream. + */ +static int __init found_pgp_key(struct pgp_parse_context *context, + enum pgp_packet_tag type, u8 headerlen, + const u8 *data, size_t datalen) +{ + struct preload_pgp_keys_context *ctx = + container_of(context, struct preload_pgp_keys_context, pgp); + + if (ctx->found_key) { + ctx->key_end = data - headerlen; + create_pgp_key(ctx); + } + + ctx->key_start = data - headerlen; + ctx->found_key = true; + return 0; +} + +/** + * preload_pgp_keys - Load keys from a PGP keyring blob + * @pgpdata: The PGP keyring blob containing the keys. + * @pgpdatalen: The size of the @pgpdata blob. + * @keyring: The keyring to add the new keys to. + * + * Preload a pack of keys from a PGP keyring blob. + * + * The keys have their descriptions generated from the user ID and fingerprint + * in the PGP stream. Since keys can be matched on their key IDs independently + * of the key description, the description is mostly irrelevant apart from the + * fact that keys of the same description displace one another from a keyring. + * + * The caller should override the current creds if they want the keys to be + * owned by someone other than the current process's owner. Keys will not be + * accounted towards the owner's quota. + * + * This function may only be called whilst the kernel is booting. + */ +int __init preload_pgp_keys(const u8 *pgpdata, size_t pgpdatalen, + struct key *keyring) +{ + struct preload_pgp_keys_context ctx; + int ret; + + ctx.pgp.types_of_interest = (1 << PGP_PKT_PUBLIC_KEY); + ctx.pgp.process_packet = found_pgp_key; + ctx.keyring = make_key_ref(keyring, 1); + ctx.found_key = false; + + ret = pgp_parse_packets(pgpdata, pgpdatalen, &ctx.pgp); + if (ret < 0) + return ret; + + if (ctx.found_key) { + ctx.key_end = pgpdata + pgpdatalen; + create_pgp_key(&ctx); + } + return 0; +} diff --git a/include/crypto/pgp.h b/include/crypto/pgp.h index a58453843dc8..fcb1c4c38a9d 100644 --- a/include/crypto/pgp.h +++ b/include/crypto/pgp.h @@ -1,5 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0+ */ -/* PGP signature processing +/* PGP key and signature processing * * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) @@ -26,4 +26,10 @@ extern void pgp_sig_verify_cancel(struct pgp_sig_verify *ctx, bool keep_sig); extern struct public_key_signature *pgp_sig_get_sig(struct pgp_sig_verify *ctx); extern u8 pgp_sig_get_version(struct pgp_sig_verify *ctx); +/* + * pgp_preload.c + */ +extern int __init preload_pgp_keys(const u8 *pgpdata, size_t pgpdatalen, + struct key *keyring); + #endif /* _CRYPTO_PGP_H */ From patchwork Tue Jan 11 18:03:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710291 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 956BBC4167D for ; Tue, 11 Jan 2022 18:06:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345417AbiAKSGb (ORCPT ); Tue, 11 Jan 2022 13:06:31 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4402 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345411AbiAKSEC (ORCPT ); Tue, 11 Jan 2022 13:04:02 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJQ13qZMz688Bk; Wed, 12 Jan 2022 02:00:25 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:58 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 14/14] KEYS: Introduce load_pgp_public_keyring() Date: Tue, 11 Jan 2022 19:03:18 +0100 Message-ID: <20220111180318.591029-15-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Preload PGP keys from 'pubring.gpg', placed in certs/ of the kernel source directory. Signed-off-by: Roberto Sassu --- certs/Kconfig | 11 +++++++++++ certs/Makefile | 7 +++++++ certs/system_certificates.S | 18 ++++++++++++++++++ certs/system_keyring.c | 21 +++++++++++++++++++++ 4 files changed, 57 insertions(+) diff --git a/certs/Kconfig b/certs/Kconfig index ae7f2e876a31..2f7fa68cd958 100644 --- a/certs/Kconfig +++ b/certs/Kconfig @@ -126,4 +126,15 @@ config SYSTEM_REVOCATION_KEYS containing X.509 certificates to be included in the default blacklist keyring. +config PGP_PRELOAD_PUBLIC_KEYS + bool "Preload PGP public keys" + depends on SYSTEM_TRUSTED_KEYRING + select PGP_PRELOAD + default n + help + Load at boot time the PGP public keys from a reserved area (populated + with the content of 'certs/pubring.gpg' provided at kernel build + time), and add them to the built-in keyring. Invalid keys are ignored + and the loading continues. + endmenu diff --git a/certs/Makefile b/certs/Makefile index 279433783b10..c85e0ff560ca 100644 --- a/certs/Makefile +++ b/certs/Makefile @@ -22,6 +22,13 @@ $(obj)/system_certificates.o: $(obj)/x509_certificate_list # Cope with signing_key.x509 existing in $(srctree) not $(objtree) AFLAGS_system_certificates.o := -I$(srctree) +ifdef CONFIG_PGP_PRELOAD_PUBLIC_KEYS +ifeq ($(shell ls $(srctree)/certs/pubring.gpg 2> /dev/null), $(srctree)/certs/pubring.gpg) +AFLAGS_system_certificates.o += -DHAVE_PUBRING_GPG +$(obj)/system_certificates.o: $(srctree)/certs/pubring.gpg +endif +endif + quiet_cmd_extract_certs = EXTRACT_CERTS $(patsubst "%",%,$(2)) cmd_extract_certs = scripts/extract-cert $(2) $@ diff --git a/certs/system_certificates.S b/certs/system_certificates.S index e1645e6f4d97..03b361bec758 100644 --- a/certs/system_certificates.S +++ b/certs/system_certificates.S @@ -47,3 +47,21 @@ module_cert_size: #else .long __module_cert_end - __module_cert_start #endif + + .align 8 + .globl pgp_public_keys +pgp_public_keys: +__pgp_key_list_start: +#ifdef HAVE_PUBRING_GPG + .incbin "certs/pubring.gpg" +#endif +__pgp_key_list_end: + + .align 8 + .globl pgp_public_keys_size +pgp_public_keys_size: +#ifdef CONFIG_64BIT + .quad __pgp_key_list_end - __pgp_key_list_start +#else + .long __pgp_key_list_end - __pgp_key_list_start +#endif diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 26a11b1dcd59..1612fb97a652 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -167,6 +167,27 @@ static __init int load_system_certificate_list(void) } late_initcall(load_system_certificate_list); +#ifdef CONFIG_PGP_PRELOAD_PUBLIC_KEYS +extern __initconst const u8 pgp_public_keys[]; +extern __initconst const unsigned long pgp_public_keys_size; + +/* + * Load a list of PGP keys. + */ +static __init int load_pgp_public_keyring(void) +{ + pr_notice("Load PGP public keys\n"); + + if (preload_pgp_keys(pgp_public_keys, + pgp_public_keys_size, + builtin_trusted_keys) < 0) + pr_err("Can't load PGP public keys\n"); + + return 0; +} +late_initcall(load_pgp_public_keyring); +#endif /* CONFIG_PGP_PRELOAD_PUBLIC_KEYS */ + #ifdef CONFIG_SYSTEM_DATA_VERIFICATION /**