From 913a7ee3584b9cdb05b473123b529677f16e4e0b Mon Sep 17 00:00:00 2001 From: June McEnroe Date: Sun, 27 Feb 2022 09:57:33 -0500 Subject: Import LibreSSL 3.5.0 --- tls_signer.c | 451 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 451 insertions(+) create mode 100644 tls_signer.c (limited to 'tls_signer.c') diff --git a/tls_signer.c b/tls_signer.c new file mode 100644 index 0000000..1f11096 --- /dev/null +++ b/tls_signer.c @@ -0,0 +1,451 @@ +/* $OpenBSD: tls_signer.c,v 1.4 2022/02/01 17:18:38 jsing Exp $ */ +/* + * Copyright (c) 2021 Eric Faurot + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include + +#include +#include +#include + +#include "tls.h" +#include "tls_internal.h" + +struct tls_signer_key { + char *hash; + RSA *rsa; + EC_KEY *ecdsa; + struct tls_signer_key *next; +}; + +struct tls_signer { + struct tls_error error; + struct tls_signer_key *keys; +}; + +static pthread_mutex_t signer_method_lock = PTHREAD_MUTEX_INITIALIZER; + +struct tls_signer * +tls_signer_new(void) +{ + struct tls_signer *signer; + + if ((signer = calloc(1, sizeof(*signer))) == NULL) + return (NULL); + + return (signer); +} + +void +tls_signer_free(struct tls_signer *signer) +{ + struct tls_signer_key *skey; + + if (signer == NULL) + return; + + tls_error_clear(&signer->error); + + while (signer->keys) { + skey = signer->keys; + signer->keys = skey->next; + RSA_free(skey->rsa); + EC_KEY_free(skey->ecdsa); + free(skey->hash); + free(skey); + } + + free(signer); +} + +const char * +tls_signer_error(struct tls_signer *signer) +{ + return (signer->error.msg); +} + +int +tls_signer_add_keypair_mem(struct tls_signer *signer, const uint8_t *cert, + size_t cert_len, const uint8_t *key, size_t key_len) +{ + struct tls_signer_key *skey = NULL; + char *errstr = "unknown"; + int ssl_err; + EVP_PKEY *pkey = NULL; + X509 *x509 = NULL; + BIO *bio = NULL; + char *hash = NULL; + + /* Compute certificate hash */ + if ((bio = BIO_new_mem_buf(cert, cert_len)) == NULL) { + tls_error_setx(&signer->error, + "failed to create certificate bio"); + goto err; + } + if ((x509 = PEM_read_bio_X509(bio, NULL, tls_password_cb, + NULL)) == NULL) { + if ((ssl_err = ERR_peek_error()) != 0) + errstr = ERR_error_string(ssl_err, NULL); + tls_error_setx(&signer->error, "failed to load certificate: %s", + errstr); + goto err; + } + if (tls_cert_pubkey_hash(x509, &hash) == -1) { + tls_error_setx(&signer->error, + "failed to get certificate hash"); + goto err; + } + + X509_free(x509); + x509 = NULL; + BIO_free(bio); + bio = NULL; + + /* Read private key */ + if ((bio = BIO_new_mem_buf(key, key_len)) == NULL) { + tls_error_setx(&signer->error, "failed to create key bio"); + goto err; + } + if ((pkey = PEM_read_bio_PrivateKey(bio, NULL, tls_password_cb, + NULL)) == NULL) { + tls_error_setx(&signer->error, "failed to read private key"); + goto err; + } + + if ((skey = calloc(1, sizeof(*skey))) == NULL) { + tls_error_set(&signer->error, "failed to create key entry"); + goto err; + } + skey->hash = hash; + if ((skey->rsa = EVP_PKEY_get1_RSA(pkey)) == NULL && + (skey->ecdsa = EVP_PKEY_get1_EC_KEY(pkey)) == NULL) { + tls_error_setx(&signer->error, "unknown key type"); + goto err; + } + + skey->next = signer->keys; + signer->keys = skey; + EVP_PKEY_free(pkey); + BIO_free(bio); + + return (0); + + err: + EVP_PKEY_free(pkey); + X509_free(x509); + BIO_free(bio); + free(hash); + free(skey); + + return (-1); +} + +int +tls_signer_add_keypair_file(struct tls_signer *signer, const char *cert_file, + const char *key_file) +{ + char *cert = NULL, *key = NULL; + size_t cert_len, key_len; + int rv = -1; + + if (tls_config_load_file(&signer->error, "certificate", cert_file, + &cert, &cert_len) == -1) + goto err; + + if (tls_config_load_file(&signer->error, "key", key_file, &key, + &key_len) == -1) + goto err; + + rv = tls_signer_add_keypair_mem(signer, cert, cert_len, key, key_len); + + err: + free(cert); + free(key); + + return (rv); +} + +static int +tls_sign_rsa(struct tls_signer *signer, struct tls_signer_key *skey, + const uint8_t *input, size_t input_len, int padding_type, + uint8_t **out_signature, size_t *out_signature_len) +{ + int rsa_padding, rsa_size, signature_len; + char *signature = NULL; + + *out_signature = NULL; + *out_signature_len = 0; + + if (padding_type == TLS_PADDING_NONE) { + rsa_padding = RSA_NO_PADDING; + } else if (padding_type == TLS_PADDING_RSA_PKCS1) { + rsa_padding = RSA_PKCS1_PADDING; + } else if (padding_type == TLS_PADDING_RSA_X9_31) { + rsa_padding = RSA_X931_PADDING; + } else { + tls_error_setx(&signer->error, "invalid RSA padding type (%d)", + padding_type); + return (-1); + } + + if (input_len > INT_MAX) { + tls_error_setx(&signer->error, "input too large"); + return (-1); + } + if ((rsa_size = RSA_size(skey->rsa)) <= 0) { + tls_error_setx(&signer->error, "invalid RSA size: %d", + rsa_size); + return (-1); + } + if ((signature = calloc(1, rsa_size)) == NULL) { + tls_error_set(&signer->error, "RSA signature"); + return (-1); + } + + if ((signature_len = RSA_private_encrypt((int)input_len, input, + signature, skey->rsa, rsa_padding)) <= 0) { + /* XXX - include further details from libcrypto. */ + tls_error_setx(&signer->error, "RSA signing failed"); + free(signature); + return (-1); + } + + *out_signature = signature; + *out_signature_len = (size_t)signature_len; + + return (0); +} + +static int +tls_sign_ecdsa(struct tls_signer *signer, struct tls_signer_key *skey, + const uint8_t *input, size_t input_len, int padding_type, + uint8_t **out_signature, size_t *out_signature_len) +{ + unsigned char *signature; + int signature_len; + + *out_signature = NULL; + *out_signature_len = 0; + + if (padding_type != TLS_PADDING_NONE) { + tls_error_setx(&signer->error, "invalid ECDSA padding"); + return (-1); + } + + if (input_len > INT_MAX) { + tls_error_setx(&signer->error, "digest too large"); + return (-1); + } + if ((signature_len = ECDSA_size(skey->ecdsa)) <= 0) { + tls_error_setx(&signer->error, "invalid ECDSA size: %d", + signature_len); + return (-1); + } + if ((signature = calloc(1, signature_len)) == NULL) { + tls_error_set(&signer->error, "ECDSA signature"); + return (-1); + } + + if (!ECDSA_sign(0, input, input_len, signature, &signature_len, + skey->ecdsa)) { + /* XXX - include further details from libcrypto. */ + tls_error_setx(&signer->error, "ECDSA signing failed"); + free(signature); + return (-1); + } + + *out_signature = signature; + *out_signature_len = signature_len; + + return (0); +} + +int +tls_signer_sign(struct tls_signer *signer, const char *pubkey_hash, + const uint8_t *input, size_t input_len, int padding_type, + uint8_t **out_signature, size_t *out_signature_len) +{ + struct tls_signer_key *skey; + + *out_signature = NULL; + *out_signature_len = 0; + + for (skey = signer->keys; skey; skey = skey->next) + if (!strcmp(pubkey_hash, skey->hash)) + break; + + if (skey == NULL) { + tls_error_setx(&signer->error, "key not found"); + return (-1); + } + + if (skey->rsa != NULL) + return tls_sign_rsa(signer, skey, input, input_len, + padding_type, out_signature, out_signature_len); + + if (skey->ecdsa != NULL) + return tls_sign_ecdsa(signer, skey, input, input_len, + padding_type, out_signature, out_signature_len); + + tls_error_setx(&signer->error, "unknown key type"); + + return (-1); +} + +static int +tls_rsa_priv_enc(int from_len, const unsigned char *from, unsigned char *to, + RSA *rsa, int rsa_padding) +{ + struct tls_config *config; + uint8_t *signature = NULL; + size_t signature_len = 0; + const char *pubkey_hash; + int padding_type; + + /* + * This function is called via RSA_private_encrypt() and has to conform + * to its calling convention/signature. The caller is required to + * provide a 'to' buffer of at least RSA_size() bytes. + */ + + pubkey_hash = RSA_get_ex_data(rsa, 0); + config = RSA_get_ex_data(rsa, 1); + + if (pubkey_hash == NULL || config == NULL) + goto err; + + if (rsa_padding == RSA_NO_PADDING) { + padding_type = TLS_PADDING_NONE; + } else if (rsa_padding == RSA_PKCS1_PADDING) { + padding_type = TLS_PADDING_RSA_PKCS1; + } else if (rsa_padding == RSA_X931_PADDING) { + padding_type = TLS_PADDING_RSA_X9_31; + } else { + goto err; + } + + if (from_len < 0) + goto err; + + if (config->sign_cb(config->sign_cb_arg, pubkey_hash, from, from_len, + padding_type, &signature, &signature_len) == -1) + goto err; + + if (signature_len > INT_MAX || (int)signature_len > RSA_size(rsa)) + goto err; + + memcpy(to, signature, signature_len); + free(signature); + + return ((int)signature_len); + + err: + free(signature); + + return (-1); +} + +RSA_METHOD * +tls_signer_rsa_method(void) +{ + static RSA_METHOD *rsa_method = NULL; + + pthread_mutex_lock(&signer_method_lock); + + if (rsa_method != NULL) + goto out; + + rsa_method = RSA_meth_new("libtls RSA method", 0); + if (rsa_method == NULL) + goto out; + + RSA_meth_set_priv_enc(rsa_method, tls_rsa_priv_enc); + + out: + pthread_mutex_unlock(&signer_method_lock); + + return (rsa_method); +} + +static ECDSA_SIG * +tls_ecdsa_do_sign(const unsigned char *dgst, int dgst_len, const BIGNUM *inv, + const BIGNUM *rp, EC_KEY *eckey) +{ + struct tls_config *config; + ECDSA_SIG *ecdsa_sig = NULL; + uint8_t *signature = NULL; + size_t signature_len = 0; + const unsigned char *p; + const char *pubkey_hash; + + /* + * This function is called via ECDSA_do_sign_ex() and has to conform + * to its calling convention/signature. + */ + + pubkey_hash = ECDSA_get_ex_data(eckey, 0); + config = ECDSA_get_ex_data(eckey, 1); + + if (pubkey_hash == NULL || config == NULL) + goto err; + + if (dgst_len < 0) + goto err; + + if (config->sign_cb(config->sign_cb_arg, pubkey_hash, dgst, dgst_len, + TLS_PADDING_NONE, &signature, &signature_len) == -1) + goto err; + + p = signature; + if ((ecdsa_sig = d2i_ECDSA_SIG(NULL, &p, signature_len)) == NULL) + goto err; + + free(signature); + + return (ecdsa_sig); + + err: + free(signature); + + return (NULL); +} + +ECDSA_METHOD * +tls_signer_ecdsa_method(void) +{ + static ECDSA_METHOD *ecdsa_method = NULL; + + pthread_mutex_lock(&signer_method_lock); + + if (ecdsa_method != NULL) + goto out; + + ecdsa_method = calloc(1, sizeof(*ecdsa_method)); + if (ecdsa_method == NULL) + goto out; + + ecdsa_method->ecdsa_do_sign = tls_ecdsa_do_sign; + ecdsa_method->name = strdup("libtls ECDSA method"); + if (ecdsa_method->name == NULL) { + free(ecdsa_method); + ecdsa_method = NULL; + } + + out: + pthread_mutex_unlock(&signer_method_lock); + + return (ecdsa_method); +} -- cgit 1.4.1