diff options
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/Kconfig | 8 | ||||
| -rw-r--r-- | crypto/Makefile | 8 | ||||
| -rw-r--r-- | crypto/rsa.c | 315 | ||||
| -rw-r--r-- | crypto/rsa_helper.c | 121 | ||||
| -rw-r--r-- | crypto/rsakey.asn1 | 5 |
5 files changed, 457 insertions, 0 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig index eb0aca4..d6b2a8b 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -100,6 +100,14 @@ config CRYPTO_AKCIPHER select CRYPTO_AKCIPHER2 select CRYPTO_ALGAPI +config CRYPTO_RSA + tristate "RSA algorithm" + select AKCIPHER + select MPILIB + select ASN1 + help + Generic implementation of the RSA public key algorithm. + config CRYPTO_MANAGER tristate "Cryptographic algorithm manager" select CRYPTO_MANAGER2 diff --git a/crypto/Makefile b/crypto/Makefile index 1ed382d..0077476 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -30,6 +30,14 @@ obj-$(CONFIG_CRYPTO_HASH2) += crypto_hash.o obj-$(CONFIG_CRYPTO_PCOMP2) += pcompress.o obj-$(CONFIG_CRYPTO_AKCIPHER2) += akcipher.o +$(obj)/rsakey-asn1.o: $(obj)/rsakey-asn1.c $(obj)/rsakey-asn1.h +clean-files += rsakey-asn1.c rsakey-asn1.h + +rsa_generic-y := rsakey-asn1.o +rsa_generic-y += rsa.o +rsa_generic-y += rsa_helper.o +obj-$(CONFIG_CRYPTO_RSA) += rsa_generic.o + cryptomgr-y := algboss.o testmgr.o obj-$(CONFIG_CRYPTO_MANAGER2) += cryptomgr.o diff --git a/crypto/rsa.c b/crypto/rsa.c new file mode 100644 index 0000000..752af06 --- /dev/null +++ b/crypto/rsa.c @@ -0,0 +1,315 @@ +/* RSA asymmetric public-key algorithm [RFC3447] + * + * Copyright (c) 2015, Intel Corporation + * Authors: Tadeusz Struk <tadeusz.struk@intel.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. + */ + +#include <linux/module.h> +#include <crypto/internal/rsa.h> +#include <crypto/internal/akcipher.h> +#include <crypto/akcipher.h> + +/* + * RSAEP function [RFC3447 sec 5.1.1] + * c = m^e mod n; + */ +static int _rsa_enc(const struct rsa_key *key, MPI c, MPI m) +{ + /* (1) Validate 0 <= m < n */ + if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0) + return -EINVAL; + + /* (2) c = m^e mod n */ + return mpi_powm(c, m, key->e, key->n); +} + +/* + * RSADP function [RFC3447 sec 5.1.2] + * m = c^d mod n; + */ +static int _rsa_dec(const struct rsa_key *key, MPI m, MPI c) +{ + /* (1) Validate 0 <= c < n */ + if (mpi_cmp_ui(c, 0) < 0 || mpi_cmp(c, key->n) >= 0) + return -EINVAL; + + /* (2) m = c^d mod n */ + return mpi_powm(m, c, key->d, key->n); +} + +/* + * RSASP1 function [RFC3447 sec 5.2.1] + * s = m^d mod n + */ +static int _rsa_sign(const struct rsa_key *key, MPI s, MPI m) +{ + /* (1) Validate 0 <= m < n */ + if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0) + return -EINVAL; + + /* (2) s = m^d mod n */ + return mpi_powm(s, m, key->d, key->n); +} + +/* + * RSAVP1 function [RFC3447 sec 5.2.2] + * m = s^e mod n; + */ +static int _rsa_verify(const struct rsa_key *key, MPI m, MPI s) +{ + /* (1) Validate 0 <= s < n */ + if (mpi_cmp_ui(s, 0) < 0 || mpi_cmp(s, key->n) >= 0) + return -EINVAL; + + /* (2) m = s^e mod n */ + return mpi_powm(m, s, key->e, key->n); +} + +static inline struct rsa_key *rsa_get_key(struct crypto_akcipher *tfm) +{ + return akcipher_tfm_ctx(tfm); +} + +static int rsa_enc(struct akcipher_request *req) +{ + struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); + const struct rsa_key *pkey = rsa_get_key(tfm); + MPI m, c = mpi_alloc(0); + int ret = 0; + int sign; + + if (!c) + return -ENOMEM; + + if (unlikely(!pkey->n || !pkey->e)) { + ret = -EINVAL; + goto err_free_c; + } + + if (req->dst_len < mpi_get_size(pkey->n)) { + req->dst_len = mpi_get_size(pkey->n); + ret = -EOVERFLOW; + goto err_free_c; + } + + m = mpi_read_raw_data(req->src, req->src_len); + if (!m) { + ret = -ENOMEM; + goto err_free_c; + } + + ret = _rsa_enc(pkey, c, m); + if (ret) + goto err_free_m; + + ret = mpi_read_buffer(c, req->dst, req->dst_len, &req->dst_len, &sign); + if (ret) + goto err_free_m; + + if (sign < 0) { + ret = -EBADMSG; + goto err_free_m; + } + +err_free_m: + mpi_free(m); +err_free_c: + mpi_free(c); + return ret; +} + +static int rsa_dec(struct akcipher_request *req) +{ + struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); + const struct rsa_key *pkey = rsa_get_key(tfm); + MPI c, m = mpi_alloc(0); + int ret = 0; + int sign; + + if (!m) + return -ENOMEM; + + if (unlikely(!pkey->n || !pkey->d)) { + ret = -EINVAL; + goto err_free_m; + } + + if (req->dst_len < mpi_get_size(pkey->n)) { + req->dst_len = mpi_get_size(pkey->n); + ret = -EOVERFLOW; + goto err_free_m; + } + + c = mpi_read_raw_data(req->src, req->src_len); + if (!c) { + ret = -ENOMEM; + goto err_free_m; + } + + ret = _rsa_dec(pkey, m, c); + if (ret) + goto err_free_c; + + ret = mpi_read_buffer(m, req->dst, req->dst_len, &req->dst_len, &sign); + if (ret) + goto err_free_c; + + if (sign < 0) { + ret = -EBADMSG; + goto err_free_c; + } + +err_free_c: + mpi_free(c); +err_free_m: + mpi_free(m); + return ret; +} + +static int rsa_sign(struct akcipher_request *req) +{ + struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); + const struct rsa_key *pkey = rsa_get_key(tfm); + MPI m, s = mpi_alloc(0); + int ret = 0; + int sign; + + if (!s) + return -ENOMEM; + + if (unlikely(!pkey->n || !pkey->d)) { + ret = -EINVAL; + goto err_free_s; + } + + if (req->dst_len < mpi_get_size(pkey->n)) { + req->dst_len = mpi_get_size(pkey->n); + ret = -EOVERFLOW; + goto err_free_s; + } + + m = mpi_read_raw_data(req->src, req->src_len); + if (!m) { + ret = -ENOMEM; + goto err_free_s; + } + + ret = _rsa_sign(pkey, s, m); + if (ret) + goto err_free_m; + + ret = mpi_read_buffer(s, req->dst, req->dst_len, &req->dst_len, &sign); + if (ret) + goto err_free_m; + + if (sign < 0) { + ret = -EBADMSG; + goto err_free_m; + } + +err_free_m: + mpi_free(m); +err_free_s: + mpi_free(s); + return ret; +} + +static int rsa_verify(struct akcipher_request *req) +{ + struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); + const struct rsa_key *pkey = rsa_get_key(tfm); + MPI s, m = mpi_alloc(0); + int ret = 0; + int sign; + + if (!m) + return -ENOMEM; + + if (unlikely(!pkey->n || !pkey->e)) { + ret = -EINVAL; + goto err_free_m; + } + + if (req->dst_len < mpi_get_size(pkey->n)) { + req->dst_len = mpi_get_size(pkey->n); + ret = -EOVERFLOW; + goto err_free_m; + } + + s = mpi_read_raw_data(req->src, req->src_len); + if (!s) { + ret = -ENOMEM; + goto err_free_m; + } + + ret = _rsa_verify(pkey, m, s); + if (ret) + goto err_free_s; + + ret = mpi_read_buffer(m, req->dst, req->dst_len, &req->dst_len, &sign); + if (ret) + goto err_free_s; + + if (sign < 0) { + ret = -EBADMSG; + goto err_free_s; + } + +err_free_s: + mpi_free(s); +err_free_m: + mpi_free(m); + return ret; +} + +static int rsa_setkey(struct crypto_akcipher *tfm, const void *key, + unsigned int keylen) +{ + struct rsa_key *pkey = akcipher_tfm_ctx(tfm); + + return rsa_parse_key(pkey, key, keylen); +} + +static void rsa_exit_tfm(struct crypto_akcipher *tfm) +{ + struct rsa_key *pkey = akcipher_tfm_ctx(tfm); + + rsa_free_key(pkey); +} + +static struct akcipher_alg rsa = { + .encrypt = rsa_enc, + .decrypt = rsa_dec, + .sign = rsa_sign, + .verify = rsa_verify, + .setkey = rsa_setkey, + .exit = rsa_exit_tfm, + .base = { + .cra_name = "rsa", + .cra_driver_name = "rsa-generic", + .cra_priority = 100, + .cra_module = THIS_MODULE, + .cra_ctxsize = sizeof(struct rsa_key), + }, +}; + +static int rsa_init(void) +{ + return crypto_register_akcipher(&rsa); +} + +static void rsa_exit(void) +{ + crypto_unregister_akcipher(&rsa); +} + +module_init(rsa_init); +module_exit(rsa_exit); +MODULE_ALIAS_CRYPTO("rsa"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("RSA generic algorithm"); diff --git a/crypto/rsa_helper.c b/crypto/rsa_helper.c new file mode 100644 index 0000000..3e8e0a9 --- /dev/null +++ b/crypto/rsa_helper.c @@ -0,0 +1,121 @@ +/* + * RSA key extract helper + * + * Copyright (c) 2015, Intel Corporation + * Authors: Tadeusz Struk <tadeusz.struk@intel.com> + * + * This program 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 2 of the License, or (at your option) + * any later version. + * + */ +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/err.h> +#include <linux/fips.h> +#include <crypto/internal/rsa.h> +#include "rsakey-asn1.h" + +int rsa_get_n(void *context, size_t hdrlen, unsigned char tag, + const void *value, size_t vlen) +{ + struct rsa_key *key = context; + + key->n = mpi_read_raw_data(value, vlen); + + if (!key->n) + return -ENOMEM; + + /* In FIPS mode only allow key size 2K & 3K */ + if (fips_enabled && (mpi_get_size(key->n) != 256 || + mpi_get_size(key->n) != 384)) { + pr_err("RSA: key size not allowed in FIPS mode\n"); + mpi_free(key->n); + key->n = NULL; + return -EINVAL; + } + return 0; +} + +int rsa_get_e(void *context, size_t hdrlen, unsigned char tag, + const void *value, size_t vlen) +{ + struct rsa_key *key = context; + + key->e = mpi_read_raw_data(value, vlen); + + if (!key->e) + return -ENOMEM; + + return 0; +} + +int rsa_get_d(void *context, size_t hdrlen, unsigned char tag, + const void *value, size_t vlen) +{ + struct rsa_key *key = context; + + key->d = mpi_read_raw_data(value, vlen); + + if (!key->d) + return -ENOMEM; + + /* In FIPS mode only allow key size 2K & 3K */ + if (fips_enabled && (mpi_get_size(key->d) != 256 || + mpi_get_size(key->d) != 384)) { + pr_err("RSA: key size not allowed in FIPS mode\n"); + mpi_free(key->d); + key->d = NULL; + return -EINVAL; + } + return 0; +} + +static void free_mpis(struct rsa_key *key) +{ + mpi_free(key->n); + mpi_free(key->e); + mpi_free(key->d); + key->n = NULL; + key->e = NULL; + key->d = NULL; +} + +/** + * rsa_free_key() - frees rsa key allocated by rsa_parse_key() + * + * @rsa_key: struct rsa_key key representation + */ +void rsa_free_key(struct rsa_key *key) +{ + free_mpis(key); +} +EXPORT_SYMBOL_GPL(rsa_free_key); + +/** + * rsa_parse_key() - extracts an rsa key from BER encoded buffer + * and stores it in the provided struct rsa_key + * + * @rsa_key: struct rsa_key key representation + * @key: key in BER format + * @key_len: length of key + * + * Return: 0 on success or error code in case of error + */ +int rsa_parse_key(struct rsa_key *rsa_key, const void *key, + unsigned int key_len) +{ + int ret; + + free_mpis(rsa_key); + ret = asn1_ber_decoder(&rsakey_decoder, rsa_key, key, key_len); + if (ret < 0) + goto error; + + return 0; +error: + free_mpis(rsa_key); + return ret; +} +EXPORT_SYMBOL_GPL(rsa_parse_key); diff --git a/crypto/rsakey.asn1 b/crypto/rsakey.asn1 new file mode 100644 index 0000000..3c7b5df --- /dev/null +++ b/crypto/rsakey.asn1 @@ -0,0 +1,5 @@ +RsaKey ::= SEQUENCE { + n INTEGER ({ rsa_get_n }), + e INTEGER ({ rsa_get_e }), + d INTEGER ({ rsa_get_d }) +} |
