[PATCH 03/14] PGPLIB: PGP definitions (RFC 4880)

From: Roberto Sassu
Date: Tue Jan 11 2022 - 13:05:34 EST


From: David Howells <dhowells@xxxxxxxxxx>

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 <dhowells@xxxxxxxxxx>
Co-developed-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
---
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@xxxxxxxxxx)
+ */
+
+#include <linux/types.h>
+
+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,
+};
--
2.32.0