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Diffstat (limited to 'src/libstrongswan/crypto/pkcs7.c')
-rw-r--r--src/libstrongswan/crypto/pkcs7.c1061
1 files changed, 1061 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/pkcs7.c b/src/libstrongswan/crypto/pkcs7.c
new file mode 100644
index 000000000..0ec19f2cd
--- /dev/null
+++ b/src/libstrongswan/crypto/pkcs7.c
@@ -0,0 +1,1061 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2002-2008 Andreas Steffen
+ * Copyright (C) 2005 Jan Hutter, Martin Willi
+ * Hochschule fuer Technik Rapperswil, Switzerland
+ *
+ * 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 <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include <library.h>
+#include <debug.h>
+
+#include <asn1/oid.h>
+#include <asn1/asn1.h>
+#include <asn1/asn1_parser.h>
+#include <credentials/certificates/x509.h>
+#include <credentials/keys/public_key.h>
+#include <crypto/pkcs9.h>
+#include <crypto/hashers/hasher.h>
+#include <crypto/crypters/crypter.h>
+#include <utils/linked_list.h>
+
+#include "pkcs7.h"
+
+typedef struct private_pkcs7_t private_pkcs7_t;
+
+/**
+ * Private data of a pkcs7_t object.
+ */
+struct private_pkcs7_t {
+ /**
+ * Public interface for this certificate.
+ */
+ pkcs7_t public;
+
+ /**
+ * contentInfo type
+ */
+ int type;
+
+ /**
+ * ASN.1 encoded content
+ */
+ chunk_t content;
+
+ /**
+ * ASN.1 parsing start level
+ */
+ u_int level;
+
+ /**
+ * retrieved data
+ */
+ chunk_t data;
+
+ /**
+ * ASN.1 encoded attributes
+ */
+ pkcs9_t *attributes;
+
+ /**
+ * Linked list of X.509 certificates
+ */
+ linked_list_t *certs;
+};
+
+METHOD(pkcs7_t, is_data, bool,
+ private_pkcs7_t *this)
+{
+ return this->type == OID_PKCS7_DATA;
+}
+
+METHOD(pkcs7_t, is_signedData, bool,
+ private_pkcs7_t *this)
+{
+ return this->type == OID_PKCS7_SIGNED_DATA;
+}
+
+METHOD(pkcs7_t, is_envelopedData, bool,
+ private_pkcs7_t *this)
+{
+ return this->type == OID_PKCS7_ENVELOPED_DATA;
+}
+
+/**
+ * ASN.1 definition of the PKCS#7 ContentInfo type
+ */
+static const asn1Object_t contentInfoObjects[] = {
+ { 0, "contentInfo", ASN1_SEQUENCE, ASN1_NONE }, /* 0 */
+ { 1, "contentType", ASN1_OID, ASN1_BODY }, /* 1 */
+ { 1, "content", ASN1_CONTEXT_C_0, ASN1_OPT |
+ ASN1_BODY }, /* 2 */
+ { 1, "end opt", ASN1_EOC, ASN1_END }, /* 3 */
+ { 0, "exit", ASN1_EOC, ASN1_EXIT }
+};
+#define PKCS7_INFO_TYPE 1
+#define PKCS7_INFO_CONTENT 2
+
+/**
+ * Parse PKCS#7 contentInfo object
+ */
+static bool parse_contentInfo(private_pkcs7_t *this)
+{
+ asn1_parser_t *parser;
+ chunk_t object;
+ int objectID;
+ bool success = FALSE;
+
+ if (!this->data.ptr)
+ {
+ return FALSE;
+ }
+
+ parser = asn1_parser_create(contentInfoObjects, this->data);
+ parser->set_top_level(parser, this->level);
+
+ while (parser->iterate(parser, &objectID, &object))
+ {
+ if (objectID == PKCS7_INFO_TYPE)
+ {
+ this->type = asn1_known_oid(object);
+ if (this->type < OID_PKCS7_DATA ||
+ this->type > OID_PKCS7_ENCRYPTED_DATA)
+ {
+ DBG1(DBG_LIB, "unknown pkcs7 content type");
+ goto end;
+ }
+ }
+ else if (objectID == PKCS7_INFO_CONTENT && object.len > 0)
+ {
+ chunk_free(&this->content);
+ this->content = chunk_clone(object);
+ }
+ }
+ success = parser->success(parser);
+
+ if (success)
+ {
+ this->level += 2;
+ chunk_free(&this->data);
+ }
+
+end:
+ parser->destroy(parser);
+ return success;
+}
+
+/**
+ * Check whether to abort the requested parsing
+ */
+static bool abort_parsing(private_pkcs7_t *this, int type)
+{
+ if (this->type != type)
+ {
+ DBG1(DBG_LIB, "pkcs7 content to be parsed is not of type '%s'",
+ oid_names[type].name);
+ return TRUE;
+ }
+ return FALSE;
+}
+
+METHOD(pkcs7_t, parse_data, bool,
+ private_pkcs7_t *this)
+{
+ chunk_t data;
+
+ if (!parse_contentInfo(this) ||
+ abort_parsing(this, OID_PKCS7_DATA))
+ {
+ return FALSE;
+ }
+ data = this->content;
+ if (data.len == 0)
+ {
+ this->data = chunk_empty;
+ return TRUE;
+ }
+ if (asn1_parse_simple_object(&data, ASN1_OCTET_STRING,
+ this->level, "data"))
+ {
+ this->data = chunk_clone(data);
+ return TRUE;
+ }
+ return FALSE;
+}
+
+/**
+ * ASN.1 definition of the PKCS#7 signedData type
+ */
+static const asn1Object_t signedDataObjects[] = {
+ { 0, "signedData", ASN1_SEQUENCE, ASN1_NONE }, /* 0 */
+ { 1, "version", ASN1_INTEGER, ASN1_BODY }, /* 1 */
+ { 1, "digestAlgorithms", ASN1_SET, ASN1_LOOP }, /* 2 */
+ { 2, "algorithm", ASN1_EOC, ASN1_RAW }, /* 3 */
+ { 1, "end loop", ASN1_EOC, ASN1_END }, /* 4 */
+ { 1, "contentInfo", ASN1_EOC, ASN1_RAW }, /* 5 */
+ { 1, "certificates", ASN1_CONTEXT_C_0, ASN1_OPT |
+ ASN1_LOOP }, /* 6 */
+ { 2, "certificate", ASN1_SEQUENCE, ASN1_OBJ }, /* 7 */
+ { 1, "end opt or loop", ASN1_EOC, ASN1_END }, /* 8 */
+ { 1, "crls", ASN1_CONTEXT_C_1, ASN1_OPT |
+ ASN1_LOOP }, /* 9 */
+ { 2, "crl", ASN1_SEQUENCE, ASN1_OBJ }, /* 10 */
+ { 1, "end opt or loop", ASN1_EOC, ASN1_END }, /* 11 */
+ { 1, "signerInfos", ASN1_SET, ASN1_LOOP }, /* 12 */
+ { 2, "signerInfo", ASN1_SEQUENCE, ASN1_NONE }, /* 13 */
+ { 3, "version", ASN1_INTEGER, ASN1_BODY }, /* 14 */
+ { 3, "issuerAndSerialNumber", ASN1_SEQUENCE, ASN1_BODY }, /* 15 */
+ { 4, "issuer", ASN1_SEQUENCE, ASN1_OBJ }, /* 16 */
+ { 4, "serial", ASN1_INTEGER, ASN1_BODY }, /* 17 */
+ { 3, "digestAlgorithm", ASN1_EOC, ASN1_RAW }, /* 18 */
+ { 3, "authenticatedAttributes", ASN1_CONTEXT_C_0, ASN1_OPT |
+ ASN1_OBJ }, /* 19 */
+ { 3, "end opt", ASN1_EOC, ASN1_END }, /* 20 */
+ { 3, "digestEncryptionAlgorithm", ASN1_EOC, ASN1_RAW }, /* 21 */
+ { 3, "encryptedDigest", ASN1_OCTET_STRING, ASN1_BODY }, /* 22 */
+ { 3, "unauthenticatedAttributes", ASN1_CONTEXT_C_1, ASN1_OPT }, /* 23 */
+ { 3, "end opt", ASN1_EOC, ASN1_END }, /* 24 */
+ { 1, "end loop", ASN1_EOC, ASN1_END }, /* 25 */
+ { 0, "exit", ASN1_EOC, ASN1_EXIT }
+};
+#define PKCS7_SIGNED_VERSION 1
+#define PKCS7_DIGEST_ALG 3
+#define PKCS7_SIGNED_CONTENT_INFO 5
+#define PKCS7_SIGNED_CERT 7
+#define PKCS7_SIGNER_INFO 13
+#define PKCS7_SIGNER_INFO_VERSION 14
+#define PKCS7_SIGNED_ISSUER 16
+#define PKCS7_SIGNED_SERIAL_NUMBER 17
+#define PKCS7_DIGEST_ALGORITHM 18
+#define PKCS7_AUTH_ATTRIBUTES 19
+#define PKCS7_DIGEST_ENC_ALGORITHM 21
+#define PKCS7_ENCRYPTED_DIGEST 22
+
+METHOD(pkcs7_t, parse_signedData, bool,
+ private_pkcs7_t *this, certificate_t *cacert)
+{
+ asn1_parser_t *parser;
+ chunk_t object;
+ int objectID, version;
+ int digest_alg = OID_UNKNOWN;
+ int enc_alg = OID_UNKNOWN;
+ int signerInfos = 0;
+ bool success = FALSE;
+
+ chunk_t encrypted_digest = chunk_empty;
+
+ if (!parse_contentInfo(this) ||
+ abort_parsing(this, OID_PKCS7_SIGNED_DATA))
+ {
+ return FALSE;
+ }
+
+ parser = asn1_parser_create(signedDataObjects, this->content);
+ parser->set_top_level(parser, this->level);
+
+ while (parser->iterate(parser, &objectID, &object))
+ {
+ u_int level = parser->get_level(parser);
+
+ switch (objectID)
+ {
+ case PKCS7_SIGNED_VERSION:
+ version = object.len ? (int)*object.ptr : 0;
+ DBG2(DBG_LIB, " v%d", version);
+ break;
+ case PKCS7_DIGEST_ALG:
+ digest_alg = asn1_parse_algorithmIdentifier(object, level, NULL);
+ break;
+ case PKCS7_SIGNED_CONTENT_INFO:
+ {
+ pkcs7_t *data = pkcs7_create_from_chunk(object, level+1);
+
+ if (!data || !data->parse_data(data))
+ {
+ DESTROY_IF(data);
+ goto end;
+ }
+ this->data = chunk_clone(data->get_data(data));
+ data->destroy(data);
+ break;
+ }
+ case PKCS7_SIGNED_CERT:
+ {
+ certificate_t *cert;
+
+ DBG2(DBG_LIB, " parsing pkcs7-wrapped certificate");
+ cert = lib->creds->create(lib->creds,
+ CRED_CERTIFICATE, CERT_X509,
+ BUILD_BLOB_ASN1_DER, object,
+ BUILD_END);
+ if (cert)
+ {
+ this->certs->insert_last(this->certs, cert);
+ }
+ break;
+ }
+ case PKCS7_SIGNER_INFO:
+ signerInfos++;
+ DBG2(DBG_LIB, " signer #%d", signerInfos);
+ break;
+ case PKCS7_SIGNER_INFO_VERSION:
+ version = object.len ? (int)*object.ptr : 0;
+ DBG2(DBG_LIB, " v%d", version);
+ break;
+ case PKCS7_SIGNED_ISSUER:
+ {
+ identification_t *issuer;
+
+ issuer = identification_create_from_encoding(ID_DER_ASN1_DN, object);
+ DBG2(DBG_LIB, " '%Y'", issuer);
+ issuer->destroy(issuer);
+ break;
+ }
+ case PKCS7_AUTH_ATTRIBUTES:
+ *object.ptr = ASN1_SET;
+ this->attributes = pkcs9_create_from_chunk(object, level+1);
+ *object.ptr = ASN1_CONTEXT_C_0;
+ break;
+ case PKCS7_DIGEST_ALGORITHM:
+ digest_alg = asn1_parse_algorithmIdentifier(object, level, NULL);
+ break;
+ case PKCS7_DIGEST_ENC_ALGORITHM:
+ enc_alg = asn1_parse_algorithmIdentifier(object, level, NULL);
+ break;
+ case PKCS7_ENCRYPTED_DIGEST:
+ encrypted_digest = object;
+ }
+ }
+ success = parser->success(parser);
+
+end:
+ parser->destroy(parser);
+ if (!success)
+ {
+ return FALSE;
+ }
+
+ /* check the signature only if a cacert is available */
+ if (cacert != NULL)
+ {
+ signature_scheme_t scheme;
+ public_key_t *key;
+
+ scheme = signature_scheme_from_oid(digest_alg);
+ if (scheme == SIGN_UNKNOWN)
+ {
+ DBG1(DBG_LIB, "unsupported signature scheme");
+ return FALSE;
+ }
+ if (signerInfos == 0)
+ {
+ DBG1(DBG_LIB, "no signerInfo object found");
+ return FALSE;
+ }
+ else if (signerInfos > 1)
+ {
+ DBG1(DBG_LIB, "more than one signerInfo object found");
+ return FALSE;
+ }
+ if (this->attributes == NULL)
+ {
+ DBG1(DBG_LIB, "no authenticatedAttributes object found");
+ return FALSE;
+ }
+ if (enc_alg != OID_RSA_ENCRYPTION)
+ {
+ DBG1(DBG_LIB, "only RSA digest encryption supported");
+ return FALSE;
+ }
+
+ /* verify the signature */
+ key = cacert->get_public_key(cacert);
+ if (key == NULL)
+ {
+ DBG1(DBG_LIB, "no public key found in CA certificate");
+ return FALSE;
+ }
+ if (key->verify(key, scheme,
+ this->attributes->get_encoding(this->attributes), encrypted_digest))
+ {
+ DBG2(DBG_LIB, "signature is valid");
+ }
+ else
+ {
+ DBG1(DBG_LIB, "invalid signature");
+ key->destroy(key);
+ return FALSE;
+ }
+ key->destroy(key);
+
+ if (this->data.ptr != NULL)
+ {
+ chunk_t messageDigest;
+
+ messageDigest = this->attributes->get_attribute(this->attributes,
+ OID_PKCS9_MESSAGE_DIGEST);
+ if (messageDigest.ptr == NULL)
+ {
+ DBG1(DBG_LIB, "messageDigest attribute not found");
+ return FALSE;
+ }
+ else
+ {
+ hash_algorithm_t algorithm;
+ hasher_t *hasher;
+ chunk_t hash;
+ bool valid;
+
+ algorithm = hasher_algorithm_from_oid(digest_alg);
+ hasher = lib->crypto->create_hasher(lib->crypto, algorithm);
+ if (!hasher || !hasher->allocate_hash(hasher, this->data, &hash))
+ {
+ DESTROY_IF(hasher);
+ DBG1(DBG_LIB, "hash algorithm %N not supported",
+ hash_algorithm_names, algorithm);
+ return FALSE;
+ }
+ hasher->destroy(hasher);
+ DBG3(DBG_LIB, "hash: %B", &hash);
+
+ valid = chunk_equals(messageDigest, hash);
+ free(hash.ptr);
+ if (valid)
+ {
+ DBG2(DBG_LIB, "messageDigest is valid");
+ }
+ else
+ {
+ DBG1(DBG_LIB, "invalid messageDigest");
+ return FALSE;
+ }
+ }
+ }
+ }
+ return TRUE;
+}
+
+/**
+ * ASN.1 definition of the PKCS#7 envelopedData type
+ */
+static const asn1Object_t envelopedDataObjects[] = {
+ { 0, "envelopedData", ASN1_SEQUENCE, ASN1_NONE }, /* 0 */
+ { 1, "version", ASN1_INTEGER, ASN1_BODY }, /* 1 */
+ { 1, "recipientInfos", ASN1_SET, ASN1_LOOP }, /* 2 */
+ { 2, "recipientInfo", ASN1_SEQUENCE, ASN1_BODY }, /* 3 */
+ { 3, "version", ASN1_INTEGER, ASN1_BODY }, /* 4 */
+ { 3, "issuerAndSerialNumber", ASN1_SEQUENCE, ASN1_BODY }, /* 5 */
+ { 4, "issuer", ASN1_SEQUENCE, ASN1_OBJ }, /* 6 */
+ { 4, "serial", ASN1_INTEGER, ASN1_BODY }, /* 7 */
+ { 3, "encryptionAlgorithm", ASN1_EOC, ASN1_RAW }, /* 8 */
+ { 3, "encryptedKey", ASN1_OCTET_STRING, ASN1_BODY }, /* 9 */
+ { 1, "end loop", ASN1_EOC, ASN1_END }, /* 10 */
+ { 1, "encryptedContentInfo", ASN1_SEQUENCE, ASN1_OBJ }, /* 11 */
+ { 2, "contentType", ASN1_OID, ASN1_BODY }, /* 12 */
+ { 2, "contentEncryptionAlgorithm", ASN1_EOC, ASN1_RAW }, /* 13 */
+ { 2, "encryptedContent", ASN1_CONTEXT_S_0, ASN1_BODY }, /* 14 */
+ { 0, "exit", ASN1_EOC, ASN1_EXIT }
+};
+#define PKCS7_ENVELOPED_VERSION 1
+#define PKCS7_RECIPIENT_INFO_VERSION 4
+#define PKCS7_ISSUER 6
+#define PKCS7_SERIAL_NUMBER 7
+#define PKCS7_ENCRYPTION_ALG 8
+#define PKCS7_ENCRYPTED_KEY 9
+#define PKCS7_CONTENT_TYPE 12
+#define PKCS7_CONTENT_ENC_ALGORITHM 13
+#define PKCS7_ENCRYPTED_CONTENT 14
+
+METHOD(pkcs7_t, parse_envelopedData, bool,
+ private_pkcs7_t *this, chunk_t serialNumber, private_key_t *key)
+{
+ asn1_parser_t *parser;
+ chunk_t object;
+ int objectID, version;
+ bool success = FALSE;
+
+ chunk_t iv = chunk_empty;
+ chunk_t symmetric_key = chunk_empty;
+ chunk_t encrypted_content = chunk_empty;
+
+ crypter_t *crypter = NULL;
+
+ if (!parse_contentInfo(this) ||
+ abort_parsing(this, OID_PKCS7_ENVELOPED_DATA))
+ {
+ return FALSE;
+ }
+
+ parser = asn1_parser_create(envelopedDataObjects, this->content);
+ parser->set_top_level(parser, this->level);
+
+ while (parser->iterate(parser, &objectID, &object))
+ {
+ u_int level = parser->get_level(parser);
+
+ switch (objectID)
+ {
+ case PKCS7_ENVELOPED_VERSION:
+ {
+ version = object.len ? (int)*object.ptr : 0;
+ DBG2(DBG_LIB, " v%d", version);
+ if (version != 0)
+ {
+ DBG1(DBG_LIB, "envelopedData version is not 0");
+ goto end;
+ }
+ break;
+ }
+ case PKCS7_RECIPIENT_INFO_VERSION:
+ {
+ version = object.len ? (int)*object.ptr : 0;
+ DBG2(DBG_LIB, " v%d", version);
+ if (version != 0)
+ {
+ DBG1(DBG_LIB, "recipient info version is not 0");
+ goto end;
+ }
+ break;
+ }
+ case PKCS7_ISSUER:
+ {
+ identification_t *issuer;
+
+ issuer = identification_create_from_encoding(ID_DER_ASN1_DN,
+ object);
+ DBG2(DBG_LIB, " '%Y'", issuer);
+ issuer->destroy(issuer);
+ break;
+ }
+ case PKCS7_SERIAL_NUMBER:
+ {
+ if (!chunk_equals(serialNumber, object))
+ {
+ DBG1(DBG_LIB, "serial numbers do not match");
+ goto end;
+ }
+ break;
+ }
+ case PKCS7_ENCRYPTION_ALG:
+ {
+ int alg;
+
+ alg = asn1_parse_algorithmIdentifier(object, level, NULL);
+ if (alg != OID_RSA_ENCRYPTION)
+ {
+ DBG1(DBG_LIB, "only rsa encryption supported");
+ goto end;
+ }
+ break;
+ }
+ case PKCS7_ENCRYPTED_KEY:
+ {
+ if (!key->decrypt(key, ENCRYPT_RSA_PKCS1, object, &symmetric_key))
+ {
+ DBG1(DBG_LIB, "symmetric key could not be decrypted with rsa");
+ goto end;
+ }
+ DBG4(DBG_LIB, "symmetric key %B", &symmetric_key);
+ break;
+ }
+ case PKCS7_CONTENT_TYPE:
+ {
+ if (asn1_known_oid(object) != OID_PKCS7_DATA)
+ {
+ DBG1(DBG_LIB, "encrypted content not of type pkcs7 data");
+ goto end;
+ }
+ break;
+ }
+ case PKCS7_CONTENT_ENC_ALGORITHM:
+ {
+ encryption_algorithm_t enc_alg;
+ size_t key_size;
+ int alg;
+
+ alg = asn1_parse_algorithmIdentifier(object, level, &iv);
+ enc_alg = encryption_algorithm_from_oid(alg, &key_size);
+ if (enc_alg == ENCR_UNDEFINED)
+ {
+ DBG1(DBG_LIB, "unsupported content encryption algorithm");
+ goto end;
+ }
+ crypter = lib->crypto->create_crypter(lib->crypto, enc_alg,
+ key_size);
+ if (crypter == NULL)
+ {
+ DBG1(DBG_LIB, "crypter %N not available",
+ encryption_algorithm_names, enc_alg);
+ goto end;
+ }
+ if (symmetric_key.len != crypter->get_key_size(crypter))
+ {
+ DBG1(DBG_LIB, "symmetric key length %d is wrong",
+ symmetric_key.len);
+ goto end;
+ }
+ if (!asn1_parse_simple_object(&iv, ASN1_OCTET_STRING,
+ level + 1, "IV"))
+ {
+ DBG1(DBG_LIB, "IV could not be parsed");
+ goto end;
+ }
+ if (iv.len != crypter->get_iv_size(crypter))
+ {
+ DBG1(DBG_LIB, "IV length %d is wrong", iv.len);
+ goto end;
+ }
+ break;
+ }
+ case PKCS7_ENCRYPTED_CONTENT:
+ {
+ encrypted_content = object;
+ break;
+ }
+ }
+ }
+ success = parser->success(parser);
+
+end:
+ parser->destroy(parser);
+ if (!success)
+ {
+ goto failed;
+ }
+ success = FALSE;
+
+ /* decrypt the content */
+ if (!crypter->set_key(crypter, symmetric_key) ||
+ !crypter->decrypt(crypter, encrypted_content, iv, &this->data))
+ {
+ success = FALSE;
+ goto failed;
+ }
+ DBG4(DBG_LIB, "decrypted content with padding: %B", &this->data);
+
+ /* remove the padding */
+ {
+ u_char *pos = this->data.ptr + this->data.len - 1;
+ u_char pattern = *pos;
+ size_t padding = pattern;
+
+ if (padding > this->data.len)
+ {
+ DBG1(DBG_LIB, "padding greater than data length");
+ goto failed;
+ }
+ this->data.len -= padding;
+
+ while (padding-- > 0)
+ {
+ if (*pos-- != pattern)
+ {
+ DBG1(DBG_LIB, "wrong padding pattern");
+ goto failed;
+ }
+ }
+ }
+ success = TRUE;
+
+failed:
+ DESTROY_IF(crypter);
+ chunk_clear(&symmetric_key);
+ if (!success)
+ {
+ chunk_free(&this->data);
+ }
+ return success;
+}
+
+METHOD(pkcs7_t, get_data, chunk_t,
+ private_pkcs7_t *this)
+{
+ return this->data;
+}
+
+METHOD(pkcs7_t, get_contentInfo, chunk_t,
+ private_pkcs7_t *this)
+{
+ chunk_t content_type;
+
+ /* create DER-encoded OID for pkcs7_contentInfo type */
+ switch(this->type)
+ {
+ case OID_PKCS7_DATA:
+ case OID_PKCS7_SIGNED_DATA:
+ case OID_PKCS7_ENVELOPED_DATA:
+ case OID_PKCS7_SIGNED_ENVELOPED_DATA:
+ case OID_PKCS7_DIGESTED_DATA:
+ case OID_PKCS7_ENCRYPTED_DATA:
+ content_type = asn1_build_known_oid(this->type);
+ break;
+ case OID_UNKNOWN:
+ default:
+ DBG1(DBG_LIB, "invalid pkcs7 contentInfo type");
+ return chunk_empty;
+ }
+
+ return this->content.ptr == NULL
+ ? asn1_wrap(ASN1_SEQUENCE, "m", content_type)
+ : asn1_wrap(ASN1_SEQUENCE, "mm", content_type,
+ asn1_simple_object(ASN1_CONTEXT_C_0, this->content));
+}
+
+METHOD(pkcs7_t, create_certificate_enumerator, enumerator_t*,
+ private_pkcs7_t *this)
+{
+ return this->certs->create_enumerator(this->certs);
+}
+
+METHOD(pkcs7_t, set_certificate, void,
+ private_pkcs7_t *this, certificate_t *cert)
+{
+ if (cert)
+ {
+ this->certs->insert_last(this->certs, cert);
+ }
+}
+
+METHOD(pkcs7_t, set_attributes, void,
+ private_pkcs7_t *this, pkcs9_t *attributes)
+{
+ this->attributes = attributes;
+}
+
+METHOD(pkcs7_t, get_attributes, pkcs9_t*,
+ private_pkcs7_t *this)
+{
+ return this->attributes;
+}
+
+/**
+ * build a DER-encoded issuerAndSerialNumber object
+ */
+chunk_t pkcs7_build_issuerAndSerialNumber(certificate_t *cert)
+{
+ identification_t *issuer = cert->get_issuer(cert);
+ chunk_t serial = chunk_empty;
+
+ if (cert->get_type(cert) == CERT_X509)
+ {
+ x509_t *x509 = (x509_t*)cert;
+ serial = x509->get_serial(x509);
+ }
+
+ return asn1_wrap(ASN1_SEQUENCE, "cm",
+ issuer->get_encoding(issuer),
+ asn1_integer("c", serial));
+}
+
+METHOD(pkcs7_t, build_envelopedData, bool,
+ private_pkcs7_t *this, certificate_t *cert, encryption_algorithm_t alg,
+ size_t key_size)
+{
+ chunk_t iv, symmetricKey, protectedKey, in, out;
+ crypter_t *crypter;
+ int alg_oid;
+
+ /* select OID of symmetric encryption algorithm */
+ alg_oid = encryption_algorithm_to_oid(alg, key_size);
+ if (alg_oid == OID_UNKNOWN)
+ {
+ DBG1(DBG_LIB, " encryption algorithm %N not supported",
+ encryption_algorithm_names, alg);
+ return FALSE;
+ }
+ crypter = lib->crypto->create_crypter(lib->crypto, alg, key_size / 8);
+ if (crypter == NULL)
+ {
+ DBG1(DBG_LIB, " could not create crypter for algorithm %N",
+ encryption_algorithm_names, alg);
+ return FALSE;
+ }
+
+ /* generate a true random symmetric encryption key
+ * and a pseudo-random iv
+ */
+ {
+ rng_t *rng;
+
+ rng = lib->crypto->create_rng(lib->crypto, RNG_TRUE);
+ if (!rng || !rng->allocate_bytes(rng, crypter->get_key_size(crypter),
+ &symmetricKey))
+ {
+ DBG1(DBG_LIB, " failed to allocate symmetric encryption key");
+ DESTROY_IF(rng);
+ return FALSE;
+ }
+ DBG4(DBG_LIB, " symmetric encryption key: %B", &symmetricKey);
+ rng->destroy(rng);
+
+ rng = lib->crypto->create_rng(lib->crypto, RNG_WEAK);
+ if (!rng || !rng->allocate_bytes(rng, crypter->get_iv_size(crypter),
+ &iv))
+ {
+ DBG1(DBG_LIB, " failed to allocate initialization vector");
+ DESTROY_IF(rng);
+ return FALSE;
+ }
+ DBG4(DBG_LIB, " initialization vector: %B", &iv);
+ rng->destroy(rng);
+ }
+
+ /* pad the data so that the total length becomes
+ * a multiple of the block size
+ */
+ {
+ size_t block_size = crypter->get_block_size(crypter);
+ size_t padding = block_size - this->data.len % block_size;
+
+ in.len = this->data.len + padding;
+ in.ptr = malloc(in.len);
+
+ DBG2(DBG_LIB, " padding %d bytes of data to multiple block size of %d bytes",
+ (int)this->data.len, (int)in.len);
+
+ /* copy data */
+ memcpy(in.ptr, this->data.ptr, this->data.len);
+ /* append padding */
+ memset(in.ptr + this->data.len, padding, padding);
+ }
+ DBG3(DBG_LIB, " padded unencrypted data: %B", &in);
+
+ /* symmetric encryption of data object */
+ if (!crypter->set_key(crypter, symmetricKey) ||
+ !crypter->encrypt(crypter, in, iv, &out))
+ {
+ crypter->destroy(crypter);
+ chunk_clear(&in);
+ chunk_clear(&symmetricKey);
+ chunk_free(&iv);
+ return FALSE;
+ }
+ crypter->destroy(crypter);
+ chunk_clear(&in);
+ DBG3(DBG_LIB, " encrypted data: %B", &out);
+
+ /* protect symmetric key by public key encryption */
+ {
+ public_key_t *key = cert->get_public_key(cert);
+
+ if (key == NULL)
+ {
+ DBG1(DBG_LIB, " public key not found in encryption certificate");
+ chunk_clear(&symmetricKey);
+ chunk_free(&iv);
+ chunk_free(&out);
+ return FALSE;
+ }
+ key->encrypt(key, ENCRYPT_RSA_PKCS1, symmetricKey, &protectedKey);
+ key->destroy(key);
+ chunk_clear(&symmetricKey);
+ }
+
+ /* build pkcs7 enveloped data object */
+ {
+ chunk_t contentEncryptionAlgorithm = asn1_wrap(ASN1_SEQUENCE, "mm",
+ asn1_build_known_oid(alg_oid),
+ asn1_wrap(ASN1_OCTET_STRING, "m", iv));
+
+ chunk_t encryptedContentInfo = asn1_wrap(ASN1_SEQUENCE, "mmm",
+ asn1_build_known_oid(OID_PKCS7_DATA),
+ contentEncryptionAlgorithm,
+ asn1_wrap(ASN1_CONTEXT_S_0, "m", out));
+
+ chunk_t encryptedKey = asn1_wrap(ASN1_OCTET_STRING, "m", protectedKey);
+
+ chunk_t recipientInfo = asn1_wrap(ASN1_SEQUENCE, "cmmm",
+ ASN1_INTEGER_0,
+ pkcs7_build_issuerAndSerialNumber(cert),
+ asn1_algorithmIdentifier(OID_RSA_ENCRYPTION),
+ encryptedKey);
+
+ this->content = asn1_wrap(ASN1_SEQUENCE, "cmm",
+ ASN1_INTEGER_0,
+ asn1_wrap(ASN1_SET, "m", recipientInfo),
+ encryptedContentInfo);
+ chunk_free(&this->data);
+ this->type = OID_PKCS7_ENVELOPED_DATA;
+ this->data = get_contentInfo(this);
+ }
+ return TRUE;
+}
+
+METHOD(pkcs7_t, build_signedData, bool,
+ private_pkcs7_t *this, private_key_t *private_key, hash_algorithm_t alg)
+{
+ chunk_t authenticatedAttributes = chunk_empty;
+ chunk_t encryptedDigest = chunk_empty;
+ chunk_t signerInfo, encoding = chunk_empty;
+ signature_scheme_t scheme;
+ int digest_oid;
+ certificate_t *cert;
+
+ if (this->certs->get_first(this->certs, (void**)&cert) != SUCCESS)
+ {
+ DBG1(DBG_LIB, " no pkcs7 signer certificate found");
+ return FALSE;
+ }
+ digest_oid = hasher_algorithm_to_oid(alg);
+ scheme = signature_scheme_from_oid(digest_oid);
+
+ if (this->attributes != NULL)
+ {
+ if (this->data.ptr != NULL)
+ {
+ chunk_t messageDigest, signingTime, attributes;
+ hasher_t *hasher;
+ time_t now;
+
+ hasher = lib->crypto->create_hasher(lib->crypto, alg);
+ if (!hasher ||
+ !hasher->allocate_hash(hasher, this->data, &messageDigest))
+ {
+ DESTROY_IF(hasher);
+ DBG1(DBG_LIB, " hash algorithm %N not support",
+ hash_algorithm_names, alg);
+ return FALSE;
+ }
+ hasher->destroy(hasher);
+ this->attributes->set_attribute(this->attributes,
+ OID_PKCS9_MESSAGE_DIGEST,
+ messageDigest);
+ free(messageDigest.ptr);
+
+ /* take the current time as signingTime */
+ now = time(NULL);
+ signingTime = asn1_from_time(&now, ASN1_UTCTIME);
+ this->attributes->set_attribute_raw(this->attributes,
+ OID_PKCS9_SIGNING_TIME, signingTime);
+ this->attributes->set_attribute_raw(this->attributes,
+ OID_PKCS9_CONTENT_TYPE,
+ asn1_build_known_oid(OID_PKCS7_DATA));
+
+ attributes = this->attributes->get_encoding(this->attributes);
+
+ private_key->sign(private_key, scheme, attributes, &encryptedDigest);
+ authenticatedAttributes = chunk_clone(attributes);
+ *authenticatedAttributes.ptr = ASN1_CONTEXT_C_0;
+ }
+ }
+ else if (this->data.ptr != NULL)
+ {
+ private_key->sign(private_key, scheme, this->data, &encryptedDigest);
+ }
+ if (encryptedDigest.ptr)
+ {
+ encryptedDigest = asn1_wrap(ASN1_OCTET_STRING, "m", encryptedDigest);
+ }
+ signerInfo = asn1_wrap(ASN1_SEQUENCE, "cmmmmm",
+ ASN1_INTEGER_1,
+ pkcs7_build_issuerAndSerialNumber(cert),
+ asn1_algorithmIdentifier(digest_oid),
+ authenticatedAttributes,
+ asn1_algorithmIdentifier(OID_RSA_ENCRYPTION),
+ encryptedDigest);
+
+ if (this->data.ptr != NULL)
+ {
+ chunk_free(&this->content);
+ this->content = asn1_simple_object(ASN1_OCTET_STRING, this->data);
+ chunk_free(&this->data);
+ }
+ this->type = OID_PKCS7_DATA;
+ this->data = get_contentInfo(this);
+ chunk_free(&this->content);
+
+ cert->get_encoding(cert, CERT_ASN1_DER, &encoding);
+
+ this->content = asn1_wrap(ASN1_SEQUENCE, "cmcmm",
+ ASN1_INTEGER_1,
+ asn1_wrap(ASN1_SET, "m", asn1_algorithmIdentifier(digest_oid)),
+ this->data,
+ asn1_wrap(ASN1_CONTEXT_C_0, "m", encoding),
+ asn1_wrap(ASN1_SET, "m", signerInfo));
+ chunk_free(&this->data);
+ this->type = OID_PKCS7_SIGNED_DATA;
+ this->data = get_contentInfo(this);
+
+ return TRUE;
+}
+
+METHOD(pkcs7_t, destroy, void,
+ private_pkcs7_t *this)
+{
+ DESTROY_IF(this->attributes);
+ this->certs->destroy_offset(this->certs, offsetof(certificate_t, destroy));
+ free(this->content.ptr);
+ free(this->data.ptr);
+ free(this);
+}
+
+/**
+ * Generic private constructor
+ */
+static private_pkcs7_t *pkcs7_create_empty(void)
+{
+ private_pkcs7_t *this;
+
+ INIT(this,
+ .public = {
+ .is_data = _is_data,
+ .is_signedData = _is_signedData,
+ .is_envelopedData = _is_envelopedData,
+ .parse_data = _parse_data,
+ .parse_signedData = _parse_signedData,
+ .parse_envelopedData = _parse_envelopedData,
+ .get_data = _get_data,
+ .get_contentInfo = _get_contentInfo,
+ .create_certificate_enumerator = _create_certificate_enumerator,
+ .set_certificate = _set_certificate,
+ .set_attributes = _set_attributes,
+ .get_attributes = _get_attributes,
+ .build_envelopedData = _build_envelopedData,
+ .build_signedData = _build_signedData,
+ .destroy = _destroy,
+ },
+ .type = OID_UNKNOWN,
+ .certs = linked_list_create(),
+ );
+
+ return this;
+}
+
+/*
+ * Described in header.
+ */
+pkcs7_t *pkcs7_create_from_chunk(chunk_t chunk, u_int level)
+{
+ private_pkcs7_t *this = pkcs7_create_empty();
+
+ this->level = level;
+ this->data = chunk_clone(chunk);
+
+ return &this->public;
+}
+
+/*
+ * Described in header.
+ */
+pkcs7_t *pkcs7_create_from_data(chunk_t data)
+{
+ private_pkcs7_t *this = pkcs7_create_empty();
+
+ this->data = chunk_clone(data);
+
+ return &this->public;
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-10 14:44:58 +0000