From 6eb4272f570c5050b4b512361d1d0c15754b37f2 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Tue, 14 Jun 2016 16:14:58 +0300 Subject: crypto: rsa - return raw integers for the ASN.1 parser Return the raw key with no other processing so that the caller can copy it or MPI parse it, etc. The scope is to have only one ANS.1 parser for all RSA implementations. Update the RSA software implementation so that it does the MPI conversion on top. Signed-off-by: Tudor Ambarus Signed-off-by: Herbert Xu --- crypto/rsa.c | 105 +++++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 80 insertions(+), 25 deletions(-) (limited to 'crypto/rsa.c') diff --git a/crypto/rsa.c b/crypto/rsa.c index 77d737f5..dc692d43 100644 --- a/crypto/rsa.c +++ b/crypto/rsa.c @@ -10,16 +10,23 @@ */ #include +#include #include #include #include #include +struct rsa_mpi_key { + MPI n; + MPI e; + MPI d; +}; + /* * 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) +static int _rsa_enc(const struct rsa_mpi_key *key, MPI c, MPI m) { /* (1) Validate 0 <= m < n */ if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0) @@ -33,7 +40,7 @@ static int _rsa_enc(const struct rsa_key *key, MPI c, MPI m) * 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) +static int _rsa_dec(const struct rsa_mpi_key *key, MPI m, MPI c) { /* (1) Validate 0 <= c < n */ if (mpi_cmp_ui(c, 0) < 0 || mpi_cmp(c, key->n) >= 0) @@ -47,7 +54,7 @@ static int _rsa_dec(const struct rsa_key *key, MPI m, MPI c) * 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) +static int _rsa_sign(const struct rsa_mpi_key *key, MPI s, MPI m) { /* (1) Validate 0 <= m < n */ if (mpi_cmp_ui(m, 0) < 0 || mpi_cmp(m, key->n) >= 0) @@ -61,7 +68,7 @@ static int _rsa_sign(const struct rsa_key *key, MPI s, MPI m) * 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) +static int _rsa_verify(const struct rsa_mpi_key *key, MPI m, MPI s) { /* (1) Validate 0 <= s < n */ if (mpi_cmp_ui(s, 0) < 0 || mpi_cmp(s, key->n) >= 0) @@ -71,7 +78,7 @@ static int _rsa_verify(const struct rsa_key *key, MPI m, MPI s) return mpi_powm(m, s, key->e, key->n); } -static inline struct rsa_key *rsa_get_key(struct crypto_akcipher *tfm) +static inline struct rsa_mpi_key *rsa_get_key(struct crypto_akcipher *tfm) { return akcipher_tfm_ctx(tfm); } @@ -79,7 +86,7 @@ static inline struct rsa_key *rsa_get_key(struct crypto_akcipher *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); + const struct rsa_mpi_key *pkey = rsa_get_key(tfm); MPI m, c = mpi_alloc(0); int ret = 0; int sign; @@ -118,7 +125,7 @@ err_free_c: 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); + const struct rsa_mpi_key *pkey = rsa_get_key(tfm); MPI c, m = mpi_alloc(0); int ret = 0; int sign; @@ -156,7 +163,7 @@ err_free_m: 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); + const struct rsa_mpi_key *pkey = rsa_get_key(tfm); MPI m, s = mpi_alloc(0); int ret = 0; int sign; @@ -195,7 +202,7 @@ err_free_s: 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); + const struct rsa_mpi_key *pkey = rsa_get_key(tfm); MPI s, m = mpi_alloc(0); int ret = 0; int sign; @@ -233,6 +240,16 @@ err_free_m: return ret; } +static void rsa_free_mpi_key(struct rsa_mpi_key *key) +{ + mpi_free(key->d); + mpi_free(key->e); + mpi_free(key->n); + key->d = NULL; + key->e = NULL; + key->n = NULL; +} + static int rsa_check_key_length(unsigned int len) { switch (len) { @@ -251,49 +268,87 @@ static int rsa_check_key_length(unsigned int len) static int rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, unsigned int keylen) { - struct rsa_key *pkey = akcipher_tfm_ctx(tfm); + struct rsa_mpi_key *mpi_key = akcipher_tfm_ctx(tfm); + struct rsa_key raw_key = {0}; int ret; - ret = rsa_parse_pub_key(pkey, key, keylen); + /* Free the old MPI key if any */ + rsa_free_mpi_key(mpi_key); + + ret = rsa_parse_pub_key(&raw_key, key, keylen); if (ret) return ret; - if (rsa_check_key_length(mpi_get_size(pkey->n) << 3)) { - rsa_free_key(pkey); - ret = -EINVAL; + mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz); + if (!mpi_key->e) + goto err; + + mpi_key->n = mpi_read_raw_data(raw_key.n, raw_key.n_sz); + if (!mpi_key->n) + goto err; + + if (rsa_check_key_length(mpi_get_size(mpi_key->n) << 3)) { + rsa_free_mpi_key(mpi_key); + return -EINVAL; } - return ret; + + return 0; + +err: + rsa_free_mpi_key(mpi_key); + return -ENOMEM; } static int rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key, unsigned int keylen) { - struct rsa_key *pkey = akcipher_tfm_ctx(tfm); + struct rsa_mpi_key *mpi_key = akcipher_tfm_ctx(tfm); + struct rsa_key raw_key = {0}; int ret; - ret = rsa_parse_priv_key(pkey, key, keylen); + /* Free the old MPI key if any */ + rsa_free_mpi_key(mpi_key); + + ret = rsa_parse_priv_key(&raw_key, key, keylen); if (ret) return ret; - if (rsa_check_key_length(mpi_get_size(pkey->n) << 3)) { - rsa_free_key(pkey); - ret = -EINVAL; + mpi_key->d = mpi_read_raw_data(raw_key.d, raw_key.d_sz); + if (!mpi_key->d) + goto err; + + mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz); + if (!mpi_key->e) + goto err; + + mpi_key->n = mpi_read_raw_data(raw_key.n, raw_key.n_sz); + if (!mpi_key->n) + goto err; + + if (rsa_check_key_length(mpi_get_size(mpi_key->n) << 3)) { + rsa_free_mpi_key(mpi_key); + return -EINVAL; } - return ret; + + return 0; + +err: + rsa_free_mpi_key(mpi_key); + return -ENOMEM; } static int rsa_max_size(struct crypto_akcipher *tfm) { - struct rsa_key *pkey = akcipher_tfm_ctx(tfm); + struct rsa_mpi_key *pkey = akcipher_tfm_ctx(tfm); return pkey->n ? mpi_get_size(pkey->n) : -EINVAL; } static void rsa_exit_tfm(struct crypto_akcipher *tfm) { - struct rsa_key *pkey = akcipher_tfm_ctx(tfm); + struct rsa_mpi_key *pkey = akcipher_tfm_ctx(tfm); - rsa_free_key(pkey); + rsa_free_mpi_key(pkey); } static struct akcipher_alg rsa = { @@ -310,7 +365,7 @@ static struct akcipher_alg rsa = { .cra_driver_name = "rsa-generic", .cra_priority = 100, .cra_module = THIS_MODULE, - .cra_ctxsize = sizeof(struct rsa_key), + .cra_ctxsize = sizeof(struct rsa_mpi_key), }, }; -- cgit v1.2.3 From ebff06f6e2a1ae1c8454d9f59d5d6b535d9fc70e Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 29 Jun 2016 19:32:21 +0800 Subject: crypto: rsa - Generate fixed-length output Every implementation of RSA that we have naturally generates output with leading zeroes. The one and only user of RSA, pkcs1pad wants to have those leading zeroes in place, in fact because they are currently absent it has to write those zeroes itself. So we shouldn't be stripping leading zeroes in the first place. In fact this patch makes rsa-generic produce output with fixed length so that pkcs1pad does not need to do any extra work. This patch also changes DH to use the new interface. Signed-off-by: Herbert Xu --- crypto/dh.c | 2 +- crypto/rsa.c | 8 ++++---- 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'crypto/rsa.c') diff --git a/crypto/dh.c b/crypto/dh.c index 5e960fe2..9d19360e 100644 --- a/crypto/dh.c +++ b/crypto/dh.c @@ -129,7 +129,7 @@ static int dh_compute_value(struct kpp_request *req) if (ret) goto err_free_base; - ret = mpi_write_to_sgl(val, req->dst, &req->dst_len, &sign); + ret = mpi_write_to_sgl(val, req->dst, req->dst_len, &sign); if (ret) goto err_free_base; diff --git a/crypto/rsa.c b/crypto/rsa.c index dc692d43..4c280b6a 100644 --- a/crypto/rsa.c +++ b/crypto/rsa.c @@ -108,7 +108,7 @@ static int rsa_enc(struct akcipher_request *req) if (ret) goto err_free_m; - ret = mpi_write_to_sgl(c, req->dst, &req->dst_len, &sign); + ret = mpi_write_to_sgl(c, req->dst, req->dst_len, &sign); if (ret) goto err_free_m; @@ -147,7 +147,7 @@ static int rsa_dec(struct akcipher_request *req) if (ret) goto err_free_c; - ret = mpi_write_to_sgl(m, req->dst, &req->dst_len, &sign); + ret = mpi_write_to_sgl(m, req->dst, req->dst_len, &sign); if (ret) goto err_free_c; @@ -185,7 +185,7 @@ static int rsa_sign(struct akcipher_request *req) if (ret) goto err_free_m; - ret = mpi_write_to_sgl(s, req->dst, &req->dst_len, &sign); + ret = mpi_write_to_sgl(s, req->dst, req->dst_len, &sign); if (ret) goto err_free_m; @@ -226,7 +226,7 @@ static int rsa_verify(struct akcipher_request *req) if (ret) goto err_free_s; - ret = mpi_write_to_sgl(m, req->dst, &req->dst_len, &sign); + ret = mpi_write_to_sgl(m, req->dst, req->dst_len, &sign); if (ret) goto err_free_s; -- cgit v1.2.3