From patchwork Wed Sep 11 12:29:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13800430 Received: from frasgout11.his.huawei.com (frasgout11.his.huawei.com [14.137.139.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 990C51A2561; Wed, 11 Sep 2024 12:30:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=14.137.139.23 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726057809; cv=none; b=U3v4jJ90EwjiRwGOw6dJJqaG++1KQXwNhnrkCv7kE8GIT/OMIVUIZDMLcsQjFVAr8NPL8/61xjDyTwpgPW0suVheCIqGmx6T4ysl0SUV1ambrZ2dsw6tQk++9ksxguFeYheYAEBib4di40UtdId1aSP9VV5GQvebN7Ypja5BQBI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726057809; c=relaxed/simple; bh=CgFny+1sMztqzbvRL4Zo6dkUwofJasolokF6RhUK2BU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=d9YvtLQEcEfSeSO0ggjYeDp2C31U3dkKyc3aPdqeCYTQh3u1ztpm0lAgbLL9d+SFNuXEAuZjxCj2qnYixGOM2v3EWC32vcKzbqKQzMN+9oWl0qxvYsZ5NzykzHvOImKWVr5re5XpbxiI4GKwGhCzkfWZl5Nwz/6I4e+HvQV6mms= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=14.137.139.23 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.18.186.29]) by frasgout11.his.huawei.com (SkyGuard) with ESMTP id 4X3fXh4Cmdz9v7Hl; Wed, 11 Sep 2024 20:10:28 +0800 (CST) Received: from mail02.huawei.com (unknown [7.182.16.27]) by mail.maildlp.com (Postfix) with ESMTP id D65C3140123; Wed, 11 Sep 2024 20:29:57 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwD3pscjjeFmDBG3AA--.60453S6; Wed, 11 Sep 2024 13:29:57 +0100 (CET) From: Roberto Sassu To: dhowells@redhat.com, dwmw2@infradead.org, herbert@gondor.apana.org.au, davem@davemloft.net Cc: linux-kernel@vger.kernel.org, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, zohar@linux.ibm.com, linux-integrity@vger.kernel.org, torvalds@linux-foundation.org, Roberto Sassu Subject: [PATCH v3 04/14] PGPLIB: Basic packet parser Date: Wed, 11 Sep 2024 14:29:01 +0200 Message-Id: <20240911122911.1381864-5-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240911122911.1381864-1-roberto.sassu@huaweicloud.com> References: <20240911122911.1381864-1-roberto.sassu@huaweicloud.com> Precedence: bulk X-Mailing-List: keyrings@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: GxC2BwD3pscjjeFmDBG3AA--.60453S6 X-Coremail-Antispam: 1UD129KBjvJXoWxtrW5tFWftw18Zr1DtFyxXwb_yoWfKry3pa 48CryrKa1UGwn2krWrAr17WwsrCr48ZFyagayFvw1jk39FgwnYgrZFkFy0ga48KF4DJ34f urs0gFyY93Z8XrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPSb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVWxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIEc7CjxVAF wI0_Gr0_Gr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7 xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Y z7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAaw2 AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAq x4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r 43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF 7I0E14v26F4j6r4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI 0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7I U1aLvJUUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAQADBGbg-HQHzQAEsG 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 | 262 +++++++++++++++++++++++++++ crypto/asymmetric_keys/pgplib.h | 33 ++++ 4 files changed, 306 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 e1345b8f39f1..8215e3fcd8db 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -103,4 +103,10 @@ config FIPS_SIGNATURE_SELFTEST_ECDSA depends on CRYPTO_SHA256=y || CRYPTO_SHA256=FIPS_SIGNATURE_SELFTEST depends on CRYPTO_ECDSA=y || CRYPTO_ECDSA=FIPS_SIGNATURE_SELFTEST +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 9580) packet-based messages. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index bc65d3b98dcb..055b28207111 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -79,3 +79,8 @@ verify_signed_pefile-y := \ $(obj)/mscode_parser.o: $(obj)/mscode.asn1.h $(obj)/mscode.asn1.h $(obj)/mscode.asn1.o: $(obj)/mscode.asn1.c $(obj)/mscode.asn1.h + +# +# PGP handling +# +obj-$(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..1b87f8af411b --- /dev/null +++ b/crypto/asymmetric_keys/pgp_library.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0 +/* PGP packet parser (RFC 9580) + * + * 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"); +MODULE_DESCRIPTION("PGP library"); + +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", + [PGP_HASH_SHA3_256] = "sha3-256", + [PGP_HASH_SHA3_512] = "sha3-512", +}; +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 9580: 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 9580: 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 9580: 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_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 */ + + 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..3ec4b408a11e --- /dev/null +++ b/crypto/asymmetric_keys/pgplib.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* PGP library definitions (RFC 9580) + * + * 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);