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authorMartin Willi <martin@strongswan.org>2006-03-24 15:37:49 +0000
committerMartin Willi <martin@strongswan.org>2006-03-24 15:37:49 +0000
commit9c781c152ad66a73139447e40a2081c38080c651 (patch)
treee214ab37398230685621ac3732444e279c40b785 /Source/charon/transforms/certificate.c
parentdec598220b9a293c4ec75e593ab642a8945fa4fc (diff)
downloadstrongswan-9c781c152ad66a73139447e40a2081c38080c651.tar.bz2
strongswan-9c781c152ad66a73139447e40a2081c38080c651.tar.xz
- starter work on asn1 with der de/encoder
- RSA private and public key can load read key from ASN1 DER - some other fixes here and there
Diffstat (limited to 'Source/charon/transforms/certificate.c')
-rwxr-xr-xSource/charon/transforms/certificate.c518
1 files changed, 518 insertions, 0 deletions
diff --git a/Source/charon/transforms/certificate.c b/Source/charon/transforms/certificate.c
new file mode 100755
index 000000000..6d10d9f54
--- /dev/null
+++ b/Source/charon/transforms/certificate.c
@@ -0,0 +1,518 @@
+/**
+ * @file certificate.c
+ *
+ * @brief Implementation of certificate_t.
+ *
+ */
+
+/*
+ * Copyright (C) 2006 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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. See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include <gmp.h>
+
+#include "certificate.h"
+
+#include <daemon.h>
+#include <utils/allocator.h>
+#include <asn1/der_decoder.h>
+
+
+typedef struct private_certificate_t private_certificate_t;
+
+/**
+ * Private data of a certificate_t object.
+ */
+struct private_certificate_t {
+ /**
+ * Public interface for this signer.
+ */
+ certificate_t public;
+};
+
+#define OSET(x) offsetof(private_certiciate_t, x)
+
+/**
+ * Rules for de-/encoding of a certificate from/in ASN1
+ */
+static asn1_rule_t certificate_rules[] = {
+ {ASN1_SEQUENCE, 0, 0, 0 }, /* certificate */
+ { ASN1_SEQUENCE, 0, 0, 0 }, /* tbsCertificate */
+ { ASN1_TAG_E_0, ASN1_DEFAULT, OSET(version), 0 }, /* EXPLICIT version DEFAULT v1(0) */
+ { ASN1_INTEGER, 0, OSET(version), 0 },
+ { ASN1_INTEGER, 0, OSET(serial), 0 }, /* serialNumber */
+ { ASN1_SEQUENCE, 0, 0, 0 }, /* signature */
+ { ASN1_OID, 0, OSET(sign_alg), 0 }, /* algorithm */
+ { ASN1_END, 0, 0, 0 }, /* signature */
+ { ASN1_CHOICE, 0, 0, 0 }, /* issuer */
+ { ASN1_SEQUENCE, ASN1_OF, 0, 0 },
+ /* name */
+ { ASN1_END, 0, 0, 0 },
+ { ASN1_END, 0, 0, 0 }, /* issuer */
+ { ASN1_SEQUENCE, 0, 0, 0 }, /* validity */
+ { ASN1_CHOICE, 0, 0, 0 }, /* notBefore */
+ { ASN1_UTCTIME, 0, OSET(not_before), 0 }, /* utcTime */
+ { ASN1_GENERALIZEDTIME, 0, OSET(not_before), 0 }, /* generalTime */
+ { ASN1_END, 0, 0, 0 }, /* notBefore */
+ { ASN1_CHOICE, 0, 0, 0 }, /* notAfter */
+ { ASN1_UTCTIME, 0, OSET(not_after), 0 }, /* utcTime */
+ { ASN1_GENERALIZEDTIME, 0, OSET(not_after), 0 }, /* generalTime */
+ { ASN1_END, 0, 0, 0 }, /* notAfter */
+ { ASN1_END, 0, 0, 0 }, /* validity */
+ { ASN1_CHOICE, 0, 0, 0 }, /* subject */
+ { ASN1_SEQUENCE, ASN1_OF, 0, 0 },
+ /* name */
+ { ASN1_END, 0, 0, 0 },
+ { ASN1_END, 0, 0, 0 }, /* subject */
+ { ASN1_SEQUENCE, 0, 0, 0 }, /* subjectPublicKeyInfo */
+ { ASN1_OID, 0, OSET(pubkey_alg), 0 }, /* algorithm */
+ { ASN1_BITSTRING, 0, OSET(pubkey), 0 }, /* subjectPublicKey */
+ { ASN1_END, 0, 0, 0 }, /* subjectPublicKeyInfo */
+ { ASN1_TAG_I_1, ASN1_OPTIONAL, 0, OSET(has_issuer_uid)}, /* IMPLICIT issuerUniqueID OPTIONAL */
+ { ASN1_BITSTRING, 0, OSET(issuer_uid), 0 },
+ { ASN1_TAG_I_2, ASN1_OPTIONAL, 0, OSET(has_subject_uid)},/* IMPLICIT subjectUniqueID OPTIONAL */
+ { ASN1_BITSTRING, 0, OSET(subject_uid), 0 },
+ { ASN1_TAG_E_3, ASN1_OPTIONAL, 0, 0 }, /* EXPLICIT extensions OPTIONAL*/
+ { ASN1_SEQUENCE, ASN1_OF, 0, 0 },
+ /* extension */
+ { ASN1_END 0, 0, 0, }, /* extensions */
+ { ASN1_END, 0, 0, 0 }, /* certificate */
+};
+
+/**
+ * Implementation of private_certificate_t.compute_prime.
+ */
+static void compute_prime(private_certificate_t *this, size_t prime_size, mpz_t *prime)
+{
+ randomizer_t *randomizer;
+ chunk_t random_bytes;
+
+ randomizer = randomizer_create();
+ mpz_init(*prime);
+
+ do
+ {
+ randomizer->allocate_random_bytes(randomizer, prime_size, &random_bytes);
+
+ /* make sure most significant bit is set */
+ random_bytes.ptr[0] = random_bytes.ptr[0] | 0x80;
+
+ /* convert chunk to mpz value */
+ mpz_import(*prime, random_bytes.len, 1, 1, 1, 0, random_bytes.ptr);
+
+ /* get next prime */
+ mpz_nextprime (*prime, *prime);
+
+ allocator_free(random_bytes.ptr);
+ }
+ /* check if it isnt too large */
+ while (((mpz_sizeinbase(*prime, 2) + 7) / 8) > prime_size);
+
+ randomizer->destroy(randomizer);
+}
+
+/**
+ * Implementation of private_certificate_t.rsadp and private_certificate_t.rsasp1.
+ */
+static chunk_t rsadp(private_certificate_t *this, chunk_t data)
+{
+ mpz_t t1, t2;
+ chunk_t decrypted;
+
+ mpz_init(t1);
+ mpz_init(t2);
+
+ mpz_import(t1, data.len, 1, 1, 1, 0, data.ptr);
+
+ mpz_powm(t2, t1, this->exp1, this->p); /* m1 = c^dP mod p */
+ mpz_powm(t1, t1, this->exp2, this->q); /* m2 = c^dQ mod Q */
+ mpz_sub(t2, t2, t1); /* h = qInv (m1 - m2) mod p */
+ mpz_mod(t2, t2, this->p);
+ mpz_mul(t2, t2, this->coeff);
+ mpz_mod(t2, t2, this->p);
+
+ mpz_mul(t2, t2, this->q); /* m = m2 + h q */
+ mpz_add(t1, t1, t2);
+
+ decrypted.len = this->k;
+ decrypted.ptr = mpz_export(NULL, NULL, 1, decrypted.len, 1, 0, t1);
+
+ mpz_clear(t1);
+ mpz_clear(t2);
+
+ return decrypted;
+}
+
+/**
+ * Implementation of certificate.build_emsa_signature.
+ */
+static status_t build_emsa_pkcs1_signature(private_certificate_t *this, hash_algorithm_t hash_algorithm, chunk_t data, chunk_t *signature)
+{
+ hasher_t *hasher;
+ chunk_t hash;
+ chunk_t oid;
+ chunk_t em;
+
+ /* get oid string prepended to hash */
+ switch (hash_algorithm)
+ {
+ case HASH_MD2:
+ {
+ oid.ptr = md2_oid;
+ oid.len = sizeof(md2_oid);
+ break;
+ }
+ case HASH_MD5:
+ {
+ oid.ptr = md5_oid;
+ oid.len = sizeof(md5_oid);
+ break;
+ }
+ case HASH_SHA1:
+ {
+ oid.ptr = sha1_oid;
+ oid.len = sizeof(sha1_oid);
+ break;
+ }
+ case HASH_SHA256:
+ {
+ oid.ptr = sha256_oid;
+ oid.len = sizeof(sha256_oid);
+ break;
+ }
+ case HASH_SHA384:
+ {
+ oid.ptr = sha384_oid;
+ oid.len = sizeof(sha384_oid);
+ break;
+ }
+ case HASH_SHA512:
+ {
+ oid.ptr = sha512_oid;
+ oid.len = sizeof(sha512_oid);
+ break;
+ }
+ default:
+ {
+ return NOT_SUPPORTED;
+ }
+ }
+
+ /* get hasher */
+ hasher = hasher_create(hash_algorithm);
+ if (hasher == NULL)
+ {
+ return NOT_SUPPORTED;
+ }
+
+ /* build hash */
+ hasher->allocate_hash(hasher, data, &hash);
+ hasher->destroy(hasher);
+
+ /* build chunk to rsa-decrypt:
+ * EM = 0x00 || 0x01 || PS || 0x00 || T.
+ * PS = 0xFF padding, with length to fill em
+ * T = oid || hash
+ */
+ em.len = this->k;
+ em.ptr = allocator_alloc(em.len);
+
+ /* fill em with padding */
+ memset(em.ptr, 0xFF, em.len);
+ /* set magic bytes */
+ *(em.ptr) = 0x00;
+ *(em.ptr+1) = 0x01;
+ *(em.ptr + em.len - hash.len - oid.len - 1) = 0x00;
+ /* set hash */
+ memcpy(em.ptr + em.len - hash.len, hash.ptr, hash.len);
+ /* set oid */
+ memcpy(em.ptr + em.len - hash.len - oid.len, oid.ptr, oid.len);
+
+
+ /* build signature */
+ *signature = this->rsasp1(this, em);
+
+ allocator_free(hash.ptr);
+ allocator_free(em.ptr);
+
+ return SUCCESS;
+}
+
+
+/**
+ * Implementation of certificate.set_key.
+ */
+static status_t set_key(private_certificate_t *this, chunk_t key)
+{
+ der_decoder_t *dd;
+ status_t status;
+
+ dd = der_decoder_create(certificate_rules);
+
+ status = dd->decode(dd, key, this);
+ if (status == SUCCESS)
+ {
+ this->is_key_set = TRUE;
+ this->k = mpz_sizeinbase(this->n, 2) / 8;
+ }
+ dd->destroy(dd);
+ return status;
+}
+
+/**
+ * Implementation of certificate.get_key.
+ */
+static status_t get_key(private_certificate_t *this, chunk_t *key)
+{
+ if (!this->is_key_set)
+ {
+ return INVALID_STATE;
+ }
+
+ chunk_t n, e, p, q, d, exp1, exp2, coeff;
+
+ n.len = this->k;
+ n.ptr = mpz_export(NULL, NULL, 1, n.len, 1, 0, this->n);
+ e.len = this->k;
+ e.ptr = mpz_export(NULL, NULL, 1, e.len, 1, 0, this->e);
+ p.len = this->k;
+ p.ptr = mpz_export(NULL, NULL, 1, p.len, 1, 0, this->p);
+ q.len = this->k;
+ q.ptr = mpz_export(NULL, NULL, 1, q.len, 1, 0, this->q);
+ d.len = this->k;
+ d.ptr = mpz_export(NULL, NULL, 1, d.len, 1, 0, this->d);
+ exp1.len = this->k;
+ exp1.ptr = mpz_export(NULL, NULL, 1, exp1.len, 1, 0, this->exp1);
+ exp2.len = this->k;
+ exp2.ptr = mpz_export(NULL, NULL, 1, exp2.len, 1, 0, this->exp2);
+ coeff.len = this->k;
+ coeff.ptr = mpz_export(NULL, NULL, 1, coeff.len, 1, 0, this->coeff);
+
+ key->len = this->k * 8;
+ key->ptr = allocator_alloc(key->len);
+ memcpy(key->ptr + this->k * 0, n.ptr , n.len);
+ memcpy(key->ptr + this->k * 1, e.ptr, e.len);
+ memcpy(key->ptr + this->k * 2, p.ptr, p.len);
+ memcpy(key->ptr + this->k * 3, q.ptr, q.len);
+ memcpy(key->ptr + this->k * 4, d.ptr, d.len);
+ memcpy(key->ptr + this->k * 5, exp1.ptr, exp1.len);
+ memcpy(key->ptr + this->k * 6, exp2.ptr, exp2.len);
+ memcpy(key->ptr + this->k * 7, coeff.ptr, coeff.len);
+
+ allocator_free(n.ptr);
+ allocator_free(e.ptr);
+ allocator_free(p.ptr);
+ allocator_free(q.ptr);
+ allocator_free(d.ptr);
+ allocator_free(exp1.ptr);
+ allocator_free(exp2.ptr);
+ allocator_free(coeff.ptr);
+
+ return SUCCESS;
+}
+
+/**
+ * Implementation of certificate.load_key.
+ */
+static status_t load_key(private_certificate_t *this, char *file)
+{
+ return NOT_SUPPORTED;
+}
+
+/**
+ * Implementation of certificate.save_key.
+ */
+static status_t save_key(private_certificate_t *this, char *file)
+{
+ return NOT_SUPPORTED;
+}
+
+/**
+ * Implementation of certificate.generate_key.
+ */
+static status_t generate_key(private_certificate_t *this, size_t key_size)
+{
+ mpz_t p, q, n, e, d, exp1, exp2, coeff;
+ mpz_t m, q1, t;
+
+ if (key_size < 0)
+ {
+ return INVALID_ARG;
+ }
+
+ mpz_clear(this->n);
+ mpz_clear(this->e);
+ mpz_clear(this->p);
+ mpz_clear(this->q);
+ mpz_clear(this->d);
+ mpz_clear(this->exp1);
+ mpz_clear(this->exp2);
+ mpz_clear(this->coeff);
+
+ key_size = key_size / 8;
+
+ mpz_init(t);
+ mpz_init(n);
+ mpz_init(d);
+ mpz_init(exp1);
+ mpz_init(exp2);
+ mpz_init(coeff);
+
+ /* Get values of primes p and q */
+ this->compute_prime(this, key_size/2, &p);
+ this->compute_prime(this, key_size/2, &q);
+
+ /* Swapping Primes so p is larger then q */
+ if (mpz_cmp(p, q) < 0)
+ {
+ mpz_set(t, p);
+ mpz_set(p, q);
+ mpz_set(q, t);
+ }
+
+ mpz_mul(n, p, q); /* n = p*q */
+ mpz_init_set_ui(e, PUBLIC_EXPONENT); /* assign public exponent */
+ mpz_init_set(m, p); /* m = p */
+ mpz_sub_ui(m, m, 1); /* m = m -1 */
+ mpz_init_set(q1, q); /* q1 = q */
+ mpz_sub_ui(q1, q1, 1); /* q1 = q1 -1 */
+ mpz_gcd(t, m, q1); /* t = gcd(p-1, q-1) */
+ mpz_mul(m, m, q1); /* m = (p-1)*(q-1) */
+ mpz_divexact(m, m, t); /* m = m / t */
+ mpz_gcd(t, m, e); /* t = gcd(m, e) (greatest common divisor) */
+
+ mpz_invert(d, e, m); /* e has an inverse mod m */
+ if (mpz_cmp_ui(d, 0) < 0) /* make sure d is positive */
+ {
+ mpz_add(d, d, m);
+ }
+ mpz_sub_ui(t, p, 1); /* t = p-1 */
+ mpz_mod(exp1, d, t); /* exp1 = d mod p-1 */
+ mpz_sub_ui(t, q, 1); /* t = q-1 */
+ mpz_mod(exp2, d, t); /* exp2 = d mod q-1 */
+
+ mpz_invert(coeff, q, p); /* coeff = q^-1 mod p */
+ if (mpz_cmp_ui(coeff, 0) < 0) /* make coeff d is positive */
+ {
+ mpz_add(coeff, coeff, p);
+ }
+
+ mpz_clear(q1);
+ mpz_clear(m);
+ mpz_clear(t);
+
+ /* apply values */
+ *(this->p) = *p;
+ *(this->q) = *q;
+ *(this->n) = *n;
+ *(this->e) = *e;
+ *(this->d) = *d;
+ *(this->exp1) = *exp1;
+ *(this->exp2) = *exp2;
+ *(this->coeff) = *coeff;
+
+ /* set key size in bytes */
+
+ this->is_key_set = TRUE;
+ this->k = key_size;
+
+ return SUCCESS;
+}
+
+/**
+ * Implementation of certificate.get_public_key.
+ */
+rsa_public_key_t *get_public_key(private_certificate_t *this)
+{
+ rsa_public_key_t *public_key;
+ //chunk_t key;
+
+ public_key = rsa_public_key_create();
+
+ if (this->is_key_set)
+ {
+
+ chunk_t n, e, key;
+
+ n.len = this->k;
+ n.ptr = mpz_export(NULL, NULL, 1, n.len, 1, 0, this->n);
+ e.len = this->k;
+ e.ptr = mpz_export(NULL, NULL, 1, e.len, 1, 0, this->e);
+
+ key.len = this->k * 2;
+ key.ptr = allocator_alloc(key.len);
+ memcpy(key.ptr, n.ptr, n.len);
+ memcpy(key.ptr + n.len, e.ptr, e.len);
+ allocator_free(n.ptr);
+ allocator_free(e.ptr);
+
+ public_key->set_key(public_key, key);
+ allocator_free(key.ptr);
+
+ }
+
+ return public_key;
+}
+
+
+/**
+ * Implementation of certificate.destroy.
+ */
+static void destroy(private_certificate_t *this)
+{
+ mpz_clear(this->n);
+ mpz_clear(this->e);
+ mpz_clear(this->p);
+ mpz_clear(this->q);
+ mpz_clear(this->d);
+ mpz_clear(this->exp1);
+ mpz_clear(this->exp2);
+ mpz_clear(this->coeff);
+ allocator_free(this);
+}
+
+/*
+ * Described in header.
+ */
+certificate_t *certificate_create(hash_algorithm_t hash_algoritm)
+{
+ private_certificate_t *this = allocator_alloc_thing(private_certificate_t);
+
+ /* public functions */
+ this->public.build_emsa_pkcs1_signature = (status_t (*) (certificate_t*,hash_algorithm_t,chunk_t,chunk_t*))build_emsa_pkcs1_signature;
+ this->public.set_key = (status_t (*) (certificate_t*,chunk_t))set_key;
+ this->public.get_key = (status_t (*) (certificate_t*,chunk_t*))get_key;
+ this->public.load_key = (status_t (*) (certificate_t*,char*))load_key;
+ this->public.save_key = (status_t (*) (certificate_t*,char*))save_key;
+ this->public.generate_key = (status_t (*) (certificate_t*,size_t))generate_key;
+ this->public.get_public_key = (rsa_public_key_t *(*) (certificate_t*))get_public_key;
+ this->public.destroy = (void (*) (certificate_t*))destroy;
+
+ /* private functions */
+ this->rsadp = rsadp;
+ this->rsasp1 = rsadp; /* same algorithm */
+ this->compute_prime = compute_prime;
+
+ mpz_init(this->n);
+ mpz_init(this->e);
+ mpz_init(this->p);
+ mpz_init(this->q);
+ mpz_init(this->d);
+ mpz_init(this->exp1);
+ mpz_init(this->exp2);
+ mpz_init(this->coeff);
+ this->is_key_set = FALSE;
+
+ return &(this->public);
+}