diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/crypto/asymmetric_keys/rsa.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/crypto/asymmetric_keys/rsa.c')
-rw-r--r-- | kernel/crypto/asymmetric_keys/rsa.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/kernel/crypto/asymmetric_keys/rsa.c b/kernel/crypto/asymmetric_keys/rsa.c new file mode 100644 index 000000000..459cf97a7 --- /dev/null +++ b/kernel/crypto/asymmetric_keys/rsa.c @@ -0,0 +1,278 @@ +/* RSA asymmetric public-key algorithm [RFC3447] + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#define pr_fmt(fmt) "RSA: "fmt +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <crypto/algapi.h> +#include "public_key.h" + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("RSA Public Key Algorithm"); + +#define kenter(FMT, ...) \ + pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__) +#define kleave(FMT, ...) \ + pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__) + +/* + * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2]. + */ +static const u8 RSA_digest_info_MD5[] = { + 0x30, 0x20, 0x30, 0x0C, 0x06, 0x08, + 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, /* OID */ + 0x05, 0x00, 0x04, 0x10 +}; + +static const u8 RSA_digest_info_SHA1[] = { + 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, + 0x2B, 0x0E, 0x03, 0x02, 0x1A, + 0x05, 0x00, 0x04, 0x14 +}; + +static const u8 RSA_digest_info_RIPE_MD_160[] = { + 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, + 0x2B, 0x24, 0x03, 0x02, 0x01, + 0x05, 0x00, 0x04, 0x14 +}; + +static const u8 RSA_digest_info_SHA224[] = { + 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, + 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, + 0x05, 0x00, 0x04, 0x1C +}; + +static const u8 RSA_digest_info_SHA256[] = { + 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, + 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, + 0x05, 0x00, 0x04, 0x20 +}; + +static const u8 RSA_digest_info_SHA384[] = { + 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, + 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, + 0x05, 0x00, 0x04, 0x30 +}; + +static const u8 RSA_digest_info_SHA512[] = { + 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, + 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, + 0x05, 0x00, 0x04, 0x40 +}; + +static const struct { + const u8 *data; + size_t size; +} RSA_ASN1_templates[PKEY_HASH__LAST] = { +#define _(X) { RSA_digest_info_##X, sizeof(RSA_digest_info_##X) } + [HASH_ALGO_MD5] = _(MD5), + [HASH_ALGO_SHA1] = _(SHA1), + [HASH_ALGO_RIPE_MD_160] = _(RIPE_MD_160), + [HASH_ALGO_SHA256] = _(SHA256), + [HASH_ALGO_SHA384] = _(SHA384), + [HASH_ALGO_SHA512] = _(SHA512), + [HASH_ALGO_SHA224] = _(SHA224), +#undef _ +}; + +/* + * RSAVP1() function [RFC3447 sec 5.2.2] + */ +static int RSAVP1(const struct public_key *key, MPI s, MPI *_m) +{ + MPI m; + int ret; + + /* (1) Validate 0 <= s < n */ + if (mpi_cmp_ui(s, 0) < 0) { + kleave(" = -EBADMSG [s < 0]"); + return -EBADMSG; + } + if (mpi_cmp(s, key->rsa.n) >= 0) { + kleave(" = -EBADMSG [s >= n]"); + return -EBADMSG; + } + + m = mpi_alloc(0); + if (!m) + return -ENOMEM; + + /* (2) m = s^e mod n */ + ret = mpi_powm(m, s, key->rsa.e, key->rsa.n); + if (ret < 0) { + mpi_free(m); + return ret; + } + + *_m = m; + return 0; +} + +/* + * Integer to Octet String conversion [RFC3447 sec 4.1] + */ +static int RSA_I2OSP(MPI x, size_t xLen, u8 **_X) +{ + unsigned X_size, x_size; + int X_sign; + u8 *X; + + /* Make sure the string is the right length. The number should begin + * with { 0x00, 0x01, ... } so we have to account for 15 leading zero + * bits not being reported by MPI. + */ + x_size = mpi_get_nbits(x); + pr_devel("size(x)=%u xLen*8=%zu\n", x_size, xLen * 8); + if (x_size != xLen * 8 - 15) + return -ERANGE; + + X = mpi_get_buffer(x, &X_size, &X_sign); + if (!X) + return -ENOMEM; + if (X_sign < 0) { + kfree(X); + return -EBADMSG; + } + if (X_size != xLen - 1) { + kfree(X); + return -EBADMSG; + } + + *_X = X; + return 0; +} + +/* + * Perform the RSA signature verification. + * @H: Value of hash of data and metadata + * @EM: The computed signature value + * @k: The size of EM (EM[0] is an invalid location but should hold 0x00) + * @hash_size: The size of H + * @asn1_template: The DigestInfo ASN.1 template + * @asn1_size: Size of asm1_template[] + */ +static int RSA_verify(const u8 *H, const u8 *EM, size_t k, size_t hash_size, + const u8 *asn1_template, size_t asn1_size) +{ + unsigned PS_end, T_offset, i; + + kenter(",,%zu,%zu,%zu", k, hash_size, asn1_size); + + if (k < 2 + 1 + asn1_size + hash_size) + return -EBADMSG; + + /* Decode the EMSA-PKCS1-v1_5 */ + if (EM[1] != 0x01) { + kleave(" = -EBADMSG [EM[1] == %02u]", EM[1]); + return -EBADMSG; + } + + T_offset = k - (asn1_size + hash_size); + PS_end = T_offset - 1; + if (EM[PS_end] != 0x00) { + kleave(" = -EBADMSG [EM[T-1] == %02u]", EM[PS_end]); + return -EBADMSG; + } + + for (i = 2; i < PS_end; i++) { + if (EM[i] != 0xff) { + kleave(" = -EBADMSG [EM[PS%x] == %02u]", i - 2, EM[i]); + return -EBADMSG; + } + } + + if (crypto_memneq(asn1_template, EM + T_offset, asn1_size) != 0) { + kleave(" = -EBADMSG [EM[T] ASN.1 mismatch]"); + return -EBADMSG; + } + + if (crypto_memneq(H, EM + T_offset + asn1_size, hash_size) != 0) { + kleave(" = -EKEYREJECTED [EM[T] hash mismatch]"); + return -EKEYREJECTED; + } + + kleave(" = 0"); + return 0; +} + +/* + * Perform the verification step [RFC3447 sec 8.2.2]. + */ +static int RSA_verify_signature(const struct public_key *key, + const struct public_key_signature *sig) +{ + size_t tsize; + int ret; + + /* Variables as per RFC3447 sec 8.2.2 */ + const u8 *H = sig->digest; + u8 *EM = NULL; + MPI m = NULL; + size_t k; + + kenter(""); + + if (!RSA_ASN1_templates[sig->pkey_hash_algo].data) + return -ENOTSUPP; + + /* (1) Check the signature size against the public key modulus size */ + k = mpi_get_nbits(key->rsa.n); + tsize = mpi_get_nbits(sig->rsa.s); + + /* According to RFC 4880 sec 3.2, length of MPI is computed starting + * from most significant bit. So the RFC 3447 sec 8.2.2 size check + * must be relaxed to conform with shorter signatures - so we fail here + * only if signature length is longer than modulus size. + */ + pr_devel("step 1: k=%zu size(S)=%zu\n", k, tsize); + if (k < tsize) { + ret = -EBADMSG; + goto error; + } + + /* Round up and convert to octets */ + k = (k + 7) / 8; + + /* (2b) Apply the RSAVP1 verification primitive to the public key */ + ret = RSAVP1(key, sig->rsa.s, &m); + if (ret < 0) + goto error; + + /* (2c) Convert the message representative (m) to an encoded message + * (EM) of length k octets. + * + * NOTE! The leading zero byte is suppressed by MPI, so we pass a + * pointer to the _preceding_ byte to RSA_verify()! + */ + ret = RSA_I2OSP(m, k, &EM); + if (ret < 0) + goto error; + + ret = RSA_verify(H, EM - 1, k, sig->digest_size, + RSA_ASN1_templates[sig->pkey_hash_algo].data, + RSA_ASN1_templates[sig->pkey_hash_algo].size); + +error: + kfree(EM); + mpi_free(m); + kleave(" = %d", ret); + return ret; +} + +const struct public_key_algorithm RSA_public_key_algorithm = { + .name = "RSA", + .n_pub_mpi = 2, + .n_sec_mpi = 3, + .n_sig_mpi = 1, + .verify_signature = RSA_verify_signature, +}; +EXPORT_SYMBOL_GPL(RSA_public_key_algorithm); |