diff options
Diffstat (limited to 'crypto/asymmetric_keys/public_key.c')
| -rw-r--r-- | crypto/asymmetric_keys/public_key.c | 154 |
1 files changed, 100 insertions, 54 deletions
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c index 6db4c01c6503..0f8b264b3961 100644 --- a/crypto/asymmetric_keys/public_key.c +++ b/crypto/asymmetric_keys/public_key.c @@ -17,32 +17,13 @@ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/seq_file.h> +#include <linux/scatterlist.h> #include <keys/asymmetric-subtype.h> -#include "public_key.h" +#include <crypto/public_key.h> +#include <crypto/akcipher.h> MODULE_LICENSE("GPL"); -const char *const pkey_algo_name[PKEY_ALGO__LAST] = { - [PKEY_ALGO_DSA] = "DSA", - [PKEY_ALGO_RSA] = "RSA", -}; -EXPORT_SYMBOL_GPL(pkey_algo_name); - -const struct public_key_algorithm *pkey_algo[PKEY_ALGO__LAST] = { -#if defined(CONFIG_PUBLIC_KEY_ALGO_RSA) || \ - defined(CONFIG_PUBLIC_KEY_ALGO_RSA_MODULE) - [PKEY_ALGO_RSA] = &RSA_public_key_algorithm, -#endif -}; -EXPORT_SYMBOL_GPL(pkey_algo); - -const char *const pkey_id_type_name[PKEY_ID_TYPE__LAST] = { - [PKEY_ID_PGP] = "PGP", - [PKEY_ID_X509] = "X509", - [PKEY_ID_PKCS7] = "PKCS#7", -}; -EXPORT_SYMBOL_GPL(pkey_id_type_name); - /* * Provide a part of a description of the key for /proc/keys. */ @@ -52,8 +33,7 @@ static void public_key_describe(const struct key *asymmetric_key, struct public_key *key = asymmetric_key->payload.data[asym_crypto]; if (key) - seq_printf(m, "%s.%s", - pkey_id_type_name[key->id_type], key->algo->name); + seq_printf(m, "%s.%s", key->id_type, key->pkey_algo); } /* @@ -62,50 +42,116 @@ static void public_key_describe(const struct key *asymmetric_key, void public_key_destroy(void *payload) { struct public_key *key = payload; - int i; - if (key) { - for (i = 0; i < ARRAY_SIZE(key->mpi); i++) - mpi_free(key->mpi[i]); - kfree(key); - } + if (key) + kfree(key->key); + kfree(key); } EXPORT_SYMBOL_GPL(public_key_destroy); +struct public_key_completion { + struct completion completion; + int err; +}; + +static void public_key_verify_done(struct crypto_async_request *req, int err) +{ + struct public_key_completion *compl = req->data; + + if (err == -EINPROGRESS) + return; + + compl->err = err; + complete(&compl->completion); +} + /* * Verify a signature using a public key. */ -int public_key_verify_signature(const struct public_key *pk, +int public_key_verify_signature(const struct public_key *pkey, const struct public_key_signature *sig) { - const struct public_key_algorithm *algo; - - BUG_ON(!pk); - BUG_ON(!pk->mpi[0]); - BUG_ON(!pk->mpi[1]); + struct public_key_completion compl; + struct crypto_akcipher *tfm; + struct akcipher_request *req; + struct scatterlist sig_sg, digest_sg; + const char *alg_name; + char alg_name_buf[CRYPTO_MAX_ALG_NAME]; + void *output; + unsigned int outlen; + int ret = -ENOMEM; + + pr_devel("==>%s()\n", __func__); + + BUG_ON(!pkey); BUG_ON(!sig); BUG_ON(!sig->digest); - BUG_ON(!sig->mpi[0]); - - algo = pk->algo; - if (!algo) { - if (pk->pkey_algo >= PKEY_ALGO__LAST) - return -ENOPKG; - algo = pkey_algo[pk->pkey_algo]; - if (!algo) - return -ENOPKG; + BUG_ON(!sig->s); + + alg_name = sig->pkey_algo; + if (strcmp(sig->pkey_algo, "rsa") == 0) { + /* The data wangled by the RSA algorithm is typically padded + * and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447 + * sec 8.2]. + */ + if (snprintf(alg_name_buf, CRYPTO_MAX_ALG_NAME, + "pkcs1pad(rsa,%s)", sig->hash_algo + ) >= CRYPTO_MAX_ALG_NAME) + return -EINVAL; + alg_name = alg_name_buf; } - if (!algo->verify_signature) - return -ENOTSUPP; - - if (sig->nr_mpi != algo->n_sig_mpi) { - pr_debug("Signature has %u MPI not %u\n", - sig->nr_mpi, algo->n_sig_mpi); - return -EINVAL; + tfm = crypto_alloc_akcipher(alg_name, 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + req = akcipher_request_alloc(tfm, GFP_KERNEL); + if (!req) + goto error_free_tfm; + + ret = crypto_akcipher_set_pub_key(tfm, pkey->key, pkey->keylen); + if (ret) + goto error_free_req; + + outlen = crypto_akcipher_maxsize(tfm); + output = kmalloc(outlen, GFP_KERNEL); + if (!output) + goto error_free_req; + + sg_init_one(&sig_sg, sig->s, sig->s_size); + sg_init_one(&digest_sg, output, outlen); + akcipher_request_set_crypt(req, &sig_sg, &digest_sg, sig->s_size, + outlen); + init_completion(&compl.completion); + akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | + CRYPTO_TFM_REQ_MAY_SLEEP, + public_key_verify_done, &compl); + + /* Perform the verification calculation. This doesn't actually do the + * verification, but rather calculates the hash expected by the + * signature and returns that to us. + */ + ret = crypto_akcipher_verify(req); + if (ret == -EINPROGRESS) { + wait_for_completion(&compl.completion); + ret = compl.err; } - - return algo->verify_signature(pk, sig); + if (ret < 0) + goto out_free_output; + + /* Do the actual verification step. */ + if (req->dst_len != sig->digest_size || + memcmp(sig->digest, output, sig->digest_size) != 0) + ret = -EKEYREJECTED; + +out_free_output: + kfree(output); +error_free_req: + akcipher_request_free(req); +error_free_tfm: + crypto_free_akcipher(tfm); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; } EXPORT_SYMBOL_GPL(public_key_verify_signature); |