From: Roberto Sassu roberto.sassu@huawei.com
Introduce the new gpg command --conv-kernel, to convert PGP keys to the user asymmetric keys format.
The --export command cannot be used, as it would not allow to convert signatures from a file.
Signed-off-by: Roberto Sassu roberto.sassu@huawei.com --- configure.ac | 7 ++ doc/gpg.texi | 4 + g10/Makefile.am | 4 + g10/conv-packet.c | 287 ++++++++++++++++++++++++++++++++++++++++++++++ g10/conv-packet.h | 37 ++++++ g10/gpg.c | 15 ++- g10/mainproc.c | 17 ++- g10/options.h | 2 + 8 files changed, 371 insertions(+), 2 deletions(-) create mode 100644 g10/conv-packet.c create mode 100644 g10/conv-packet.h
diff --git a/configure.ac b/configure.ac index fe7e821089b..6c867e6409e 100644 --- a/configure.ac +++ b/configure.ac @@ -105,6 +105,7 @@ have_libusb=no have_libtss=no have_system_resolver=no gnupg_have_ldap="n/a" +have_uasym_support=no
use_zip=yes use_bzip2=yes @@ -1817,6 +1818,11 @@ if test x"$use_run_gnupg_user_socket" = x"yes"; then [If defined try /run/gnupg/user before /run/user]) fi
+AC_CHECK_HEADERS([linux/uasym_parser.h], [have_uasym_support=yes], []) +AM_CONDITIONAL([UASYM_KEYS_SIGS], [test "$have_uasym_support" = yes]) +if test "$have_uasym_support" = yes; then + CFLAGS="$CFLAGS -DUASYM_KEYS_SIGS" +fi
# # Decide what to build @@ -2158,6 +2164,7 @@ echo " TLS support: $use_tls_library TOFU support: $use_tofu Tor support: $show_tor_support + Uasym support: $have_uasym_support " if test "$have_libtss" != no -a -z "$TPMSERVER" -a -z "$SWTPM"; then cat <<G10EOF diff --git a/doc/gpg.texi b/doc/gpg.texi index 6b584a91306..e4d6f0adc59 100644 --- a/doc/gpg.texi +++ b/doc/gpg.texi @@ -652,6 +652,10 @@ Set the TOFU policy for all the bindings associated with the specified @pxref{trust-model-tofu}. The @var{keys} may be specified either by their fingerprint (preferred) or their keyid.
+@item --conv-kernel +@opindex conv-kernel +Convert PGP keys into a format understood by the Linux kernel. + @c @item --server @c @opindex server @c Run gpg in server mode. This feature is not yet ready for use and diff --git a/g10/Makefile.am b/g10/Makefile.am index c5691f551b1..7e6f30dc0b5 100644 --- a/g10/Makefile.am +++ b/g10/Makefile.am @@ -130,6 +130,10 @@ common_source = \ objcache.c objcache.h \ ecdh.c
+if UASYM_KEYS_SIGS +common_source += conv-packet.c +endif + gpg_sources = server.c \ $(common_source) \ pkclist.c \ diff --git a/g10/conv-packet.c b/g10/conv-packet.c new file mode 100644 index 00000000000..360db30eb8d --- /dev/null +++ b/g10/conv-packet.c @@ -0,0 +1,287 @@ +/* conv-packet.c - convert packets + * Copyright (C) 2023 Huawei Technologies Duesseldorf GmbH + * + * Author: Roberto Sassu roberto.sassu@huawei.com + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see https://www.gnu.org/licenses/. + */ + +#include <config.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <linux/types.h> +#include <linux/uasym_parser.h> +#ifdef __BIG_ENDIAN__ +#include <linux/byteorder/big_endian.h> +#else +#include <linux/byteorder/little_endian.h> +#endif +#include <linux/pub_key_info.h> + +#include "gpg.h" +#include "../common/util.h" +#include "packet.h" +#include "conv-packet.h" +#include "options.h" +#include "../common/i18n.h" + +static estream_t listfp; + +static void init_output(void) +{ + if (!listfp) + { + listfp = es_stdout; + + if (opt.outfile) { + listfp = es_fopen (opt.outfile, "wb"); + if (!listfp) { + log_error(_("cannot open %s for writing\n"), opt.outfile); + exit(1); + } + } + } +} + +/* + * Simple encoder primitives for ASN.1 BER/DER/CER + * + * Copyright (C) 2019 James.Bottomley@HansenPartnership.com + */ +static int asn1_encode_length(unsigned char *data, __u32 *data_len, __u32 len) +{ + if (len <= 0x7f) { + data[0] = len; + *data_len = 1; + return 0; + } + + if (len <= 0xff) { + data[0] = 0x81; + data[1] = len & 0xff; + *data_len = 2; + return 0; + } + + if (len <= 0xffff) { + data[0] = 0x82; + data[1] = (len >> 8) & 0xff; + data[2] = len & 0xff; + *data_len = 3; + return 0; + } + + if (len > 0xffffff) + return -EINVAL; + + data[0] = 0x83; + data[1] = (len >> 16) & 0xff; + data[2] = (len >> 8) & 0xff; + data[3] = len & 0xff; + *data_len = 4; + + return 0; +} + +static int mpis_to_asn1_sequence(gcry_mpi_t *pkey, int num_keys, + unsigned char **buffer, size_t *buffer_len) +{ + unsigned char asn1_key_len[PUBKEY_MAX_NSKEY][4]; + unsigned char asn1_seq_len[4]; + unsigned char *buffer_ptr; + __u32 asn1_key_len_len[PUBKEY_MAX_NSKEY]; + __u32 asn1_seq_len_len; + __u32 asn1_seq_payload_len = 0; + size_t nbytes; + gpg_error_t err; + int ret, i; + + for (i = 0, nbytes = 0; i < num_keys; i++) { + err = gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0, &nbytes, pkey[i]); + if (err) + return -EINVAL; + + ret = asn1_encode_length(asn1_key_len[i], &asn1_key_len_len[i], nbytes); + if (ret < 0) + return ret; + + asn1_seq_payload_len += 1 + asn1_key_len_len[i] + nbytes; + } + + ret = asn1_encode_length(asn1_seq_len, &asn1_seq_len_len, + asn1_seq_payload_len); + if (ret < 0) + return ret; + + *buffer_len = 1 + asn1_seq_len_len + asn1_seq_payload_len; + *buffer = xmalloc_clear(*buffer_len); + if (!*buffer) + return -ENOMEM; + + buffer_ptr = *buffer; + + /* ASN1_SEQUENCE */ + *buffer_ptr++ = 0x30; + memcpy(buffer_ptr, &asn1_seq_len, asn1_seq_len_len); + buffer_ptr += asn1_seq_len_len; + + for (i = 0; i < num_keys; i++) { + /* ASN1_INTEGER */ + *buffer_ptr++ = 0x02; + memcpy(buffer_ptr, &asn1_key_len[i], asn1_key_len_len[i]); + buffer_ptr += asn1_key_len_len[i]; + + err = gcry_mpi_print(GCRYMPI_FMT_USG, buffer_ptr, + *buffer_len - (buffer_ptr - *buffer), &nbytes, pkey[i]); + if (err) { + xfree(*buffer); + return -EINVAL; + } + + buffer_ptr += nbytes; + } + + *buffer_len = buffer_ptr - *buffer; + + return 0; +} + +static int pgp_to_kernel_algo(int pgp_algorithm, gcry_mpi_t pkey, __u8 *algo) +{ + char *curve = NULL; + const char *name; + int ret = 0; + + switch (pgp_algorithm) { + case PUBKEY_ALGO_RSA: + case PUBKEY_ALGO_RSA_S: + *algo = PKEY_ALGO_RSA; + break; + case PUBKEY_ALGO_ECDSA: + *algo = PKEY_ALGO_ECDSA; + if (!pkey) + break; + + curve = openpgp_oid_to_str (pkey); + name = openpgp_oid_to_curve (curve, 0); + if (!strcmp(name, "nistp192")) + *algo = PKEY_ALGO_ECDSA_P192; + else if (!strcmp(name, "nistp256")) + *algo = PKEY_ALGO_ECDSA_P256; + else if (!strcmp(name, "nistp384")) + *algo = PKEY_ALGO_ECDSA_P384; + else + ret = -EOPNOTSUPP; + break; + default: + ret = -EOPNOTSUPP; + break; + } + + xfree(curve); + return ret; +} + +int write_kernel_key(PKT_public_key *pk) +{ + unsigned char *buffer = NULL; + size_t buffer_len = 0; + struct uasym_hdr hdr = { 0 }; + struct uasym_entry e_algo = { 0 }; + struct uasym_entry e_keyid = { 0 }; + struct uasym_entry e_key_pub = { 0 }; + struct uasym_entry e_key_desc = { 0 }; + __u8 algo; + __u32 keyid[2], _keyid; + __u64 total_len = 0; + /* PGP: <keyid> */ + char key_desc[4 + 1 + 8 + 1]; + gpg_error_t err; + int ret = 0; + + init_output(); + keyid_from_pk (pk, keyid); + + ret = pgp_to_kernel_algo(pk->pubkey_algo, pk->pkey[0], &algo); + if (ret < 0) + return ret; + + /* algo */ + e_algo.field = __cpu_to_be16(KEY_ALGO); + e_algo.length = __cpu_to_be32(sizeof(algo)); + total_len += sizeof(e_algo) + sizeof(algo); + + /* key id */ + e_keyid.field = __cpu_to_be16(KEY_KID0); + e_keyid.length = __cpu_to_be32(sizeof(*pk->keyid) * 2); + total_len += sizeof(e_keyid) + sizeof(*pk->keyid) * 2; + + /* key desc */ + e_key_desc.field = __cpu_to_be16(KEY_DESC); + e_key_desc.length = __cpu_to_be32(sizeof(key_desc)); + total_len += sizeof(e_key_desc) + sizeof(key_desc); + + snprintf(key_desc, sizeof(key_desc), "PGP: %08x", pk->keyid[1]); + + switch (pk->pubkey_algo) { + case PUBKEY_ALGO_RSA: + case PUBKEY_ALGO_RSA_S: + ret = mpis_to_asn1_sequence(pk->pkey, pubkey_get_npkey(pk->pubkey_algo), + &buffer, &buffer_len); + break; + case PUBKEY_ALGO_ECDSA: + err = gcry_mpi_aprint(GCRYMPI_FMT_USG, &buffer, &buffer_len, pk->pkey[1]); + if (err) + ret = -EINVAL; + break; + default: + ret = -EOPNOTSUPP; + break; + } + + if (ret < 0) + goto out; + + /* key blob */ + e_key_pub.field = __cpu_to_be16(KEY_PUB); + e_key_pub.length = __cpu_to_be32(buffer_len); + total_len += sizeof(e_key_pub) + buffer_len; + + hdr.data_type = TYPE_KEY; + hdr.num_fields = __cpu_to_be16(4); + hdr.total_len = __cpu_to_be64(total_len); + + es_write(listfp, &hdr, sizeof(hdr), NULL); + + es_write(listfp, &e_algo, sizeof(e_algo), NULL); + es_write(listfp, &algo, sizeof(algo), NULL); + + es_write(listfp, &e_keyid, sizeof(e_keyid), NULL); + _keyid = __cpu_to_be32(pk->keyid[0]); + es_write(listfp, &_keyid, sizeof(_keyid), NULL); + _keyid = __cpu_to_be32(pk->keyid[1]); + es_write(listfp, &_keyid, sizeof(_keyid), NULL); + + es_write(listfp, &e_key_pub, sizeof(e_key_pub), NULL); + es_write(listfp, buffer, buffer_len, NULL); + + es_write(listfp, &e_key_desc, sizeof(e_key_desc), NULL); + es_write(listfp, key_desc, sizeof(key_desc), NULL); +out: + xfree(buffer); + return 0; +} diff --git a/g10/conv-packet.h b/g10/conv-packet.h new file mode 100644 index 00000000000..d35acb985fc --- /dev/null +++ b/g10/conv-packet.h @@ -0,0 +1,37 @@ +/* conv-packet.h - header of conv-packet.c + * Copyright (C) 2023 Huawei Technologies Duesseldorf GmbH + * + * Author: Roberto Sassu roberto.sassu@huawei.com + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * GnuPG is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see https://www.gnu.org/licenses/. + */ + +#ifndef G10_CONV_PACKET_H +#define G10_CONV_PACKET_H + +#include "../common/openpgpdefs.h" + +#ifdef UASYM_KEYS_SIGS +int write_kernel_key(PKT_public_key *pk); +#else +static inline int write_kernel_key(PKT_public_key *pk) +{ + (void)pk; + return 0; +} + +#endif /* UASYM_KEYS_SIGS */ +#endif /*G10_CONV_PACKET_H*/ diff --git a/g10/gpg.c b/g10/gpg.c index 6e54aa7636c..410be8ab2ad 100644 --- a/g10/gpg.c +++ b/g10/gpg.c @@ -186,6 +186,7 @@ enum cmd_and_opt_values aPasswd, aServer, aTOFUPolicy, + aConvKernel,
oMimemode, oTextmode, @@ -583,6 +584,8 @@ static gpgrt_opt_t opts[] = { ARGPARSE_c (aListSigs, "list-sig", "@"), /* alias */ ARGPARSE_c (aCheckKeys, "check-sig", "@"), /* alias */ ARGPARSE_c (aShowKeys, "show-key", "@"), /* alias */ + ARGPARSE_c (aConvKernel, "conv-kernel", + N_("convert to Linux kernel uasym format")),
@@ -2657,6 +2660,7 @@ main (int argc, char **argv)
case aCheckKeys: case aListPackets: + case aConvKernel: case aImport: case aFastImport: case aSendKeys: @@ -5381,6 +5385,12 @@ main (int argc, char **argv) log_info (_("WARNING: no command supplied." " Trying to guess what you mean ...\n")); /*FALLTHRU*/ + case aConvKernel: +#ifndef UASYM_KEYS_SIGS + log_error(_("No support for user asymmetric keys and signatures\n")); + exit(1); +#endif + /*FALLTHRU*/ case aListPackets: if( argc > 1 ) wrong_args("[filename]"); @@ -5411,7 +5421,10 @@ main (int argc, char **argv) if( cmd == aListPackets ) { opt.list_packets=1; set_packet_list_mode(1); - } + } else if( cmd == aConvKernel ) { + opt.list_packets=1; + opt.conv_kernel=1; + } rc = proc_packets (ctrl, NULL, a ); if( rc ) { diff --git a/g10/mainproc.c b/g10/mainproc.c index 7dea4972894..edef9907127 100644 --- a/g10/mainproc.c +++ b/g10/mainproc.c @@ -496,6 +496,16 @@ proc_symkey_enc (CTX c, PACKET *pkt) free_packet (pkt, NULL); }
+static void +proc_conv (PACKET *pkt) +{ + switch (pkt->pkttype) + { + case PKT_PUBLIC_KEY: write_kernel_key(pkt->pkt.public_key); break; + default: break; + } + free_packet(pkt, NULL); +}
static void proc_pubkey_enc (CTX c, PACKET *pkt) @@ -1652,7 +1662,7 @@ do_proc_packets (CTX c, iobuf_t a) continue; } newpkt = -1; - if (opt.list_packets) + if (opt.list_packets && !opt.conv_kernel) { switch (pkt->pkttype) { @@ -1665,6 +1675,11 @@ do_proc_packets (CTX c, iobuf_t a) default: newpkt = 0; break; } } + else if (opt.conv_kernel) + { + proc_conv(pkt); + newpkt = 0; + } else if (c->sigs_only) { switch (pkt->pkttype) diff --git a/g10/options.h b/g10/options.h index 914c24849f2..08125481511 100644 --- a/g10/options.h +++ b/g10/options.h @@ -26,6 +26,7 @@ #include <stdint.h> #include "main.h" #include "packet.h" +#include "conv-packet.h" #include "tofu.h" #include "../common/session-env.h" #include "../common/compliance.h" @@ -91,6 +92,7 @@ struct int list_sigs; /* list signatures */ int no_armor; int list_packets; /* Option --list-packets active. */ + int conv_kernel; /* Option --conv-kernel active. */ int def_cipher_algo; int force_mdc; int disable_mdc;