added strneq(x,y,len) macro

4 files changed, 1000 insertions, 0 deletions

diff --git a/src/libstrongswan/Makefile.am b/src/libstrongswan/Makefile.am
index 1bfe3d842..e8859ad4c 100644
--- a/src/libstrongswan/Makefile.am
+++ b/src/libstrongswan/Makefile.am
@@ -34,6 +34,7 @@ crypto/hashers/md5_hasher.c  crypto/hashers/md5_hasher.h \
 crypto/hmac.c crypto/hmac.h \
 crypto/ietf_attr_list.c crypto/ietf_attr_list.h \
 crypto/ocsp.c crypto/ocsp.h \
+crypto/pkcs7.c crypto/pkcs7.h \
 crypto/prfs/fips_prf.c crypto/prfs/fips_prf.h \
 crypto/prfs/hmac_prf.c crypto/prfs/hmac_prf.h \
 crypto/prfs/prf.c crypto/prfs/prf.h \
diff --git a/src/libstrongswan/crypto/pkcs7.c b/src/libstrongswan/crypto/pkcs7.c
new file mode 100644
index 000000000..05d0977b4
--- /dev/null
+++ b/src/libstrongswan/crypto/pkcs7.c
@@ -0,0 +1,912 @@
+/**
+ * @file pkcs7.c
+ *
+ * @brief Implementation of pkcs7_contentInfo_t.
+ *
+ */
+
+/*
+ * Copyright (C) 2005 Jan Hutter, Martin Willi
+ * Copyright (C) 2002-2005 Andreas Steffen
+ * 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.
+ *
+ * RCSID $Id$
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <library.h>
+#include "debug.h"
+
+#include <asn1/asn1.h>
+#include <asn1/oid.h>
+#include <crypto/x509.h>
+
+#include "pkcs7.h"
+
+typedef struct private_pkcs7_contentInfo_t private_pkcs7_contentInfo_t;
+
+/**
+ * Private data of a pkcs7_contentInfo_t object.
+ */
+struct private_pkcs7_contentInfo_t {
+	/**
+	 * Public interface for this certificate.
+	 */
+	pkcs7_contentInfo_t public;
+
+	/**
+	 * contentInfo type
+	 */
+	int type;
+
+	/**
+	 * ASN.1 encoded content
+	 */
+    chunk_t content;
+};
+
+/**
+ * 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 */
+};
+
+#define PKCS7_INFO_TYPE		1
+#define PKCS7_INFO_CONTENT	2
+#define PKCS7_INFO_ROOF		4
+
+/**
+ * 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 */
+};
+
+#define PKCS7_DIGEST_ALG	 		 3
+#define PKCS7_SIGNED_CONTENT_INFO	 5
+#define PKCS7_SIGNED_CERT	 		 7
+#define PKCS7_SIGNER_INFO			13
+#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
+#define PKCS7_SIGNED_ROOF			26
+
+/**
+ * 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 */
+};
+
+#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
+#define PKCS7_ENVELOPED_ROOF			15
+
+/**
+ * PKCS7 contentInfo OIDs
+ */
+static u_char ASN1_pkcs7_data_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x01
+};
+
+static u_char ASN1_pkcs7_signed_data_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x02
+};
+
+static u_char ASN1_pkcs7_enveloped_data_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x03
+};
+
+static u_char ASN1_pkcs7_signed_enveloped_data_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x04
+};
+
+static u_char ASN1_pkcs7_digested_data_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x05
+};
+
+static char ASN1_pkcs7_encrypted_data_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x07, 0x06
+};
+
+static const chunk_t ASN1_pkcs7_data_oid = 
+						chunk_from_buf(ASN1_pkcs7_data_oid_str);
+static const chunk_t ASN1_pkcs7_signed_data_oid =
+						chunk_from_buf(ASN1_pkcs7_signed_data_oid_str);
+static const chunk_t ASN1_pkcs7_enveloped_data_oid =
+						chunk_from_buf(ASN1_pkcs7_enveloped_data_oid_str);
+static const chunk_t ASN1_pkcs7_signed_enveloped_data_oid = 
+						chunk_from_buf(ASN1_pkcs7_signed_enveloped_data_oid_str);
+static const chunk_t ASN1_pkcs7_digested_data_oid =
+						chunk_from_buf(ASN1_pkcs7_digested_data_oid_str);
+static const chunk_t ASN1_pkcs7_encrypted_data_oid =
+						chunk_from_buf(ASN1_pkcs7_encrypted_data_oid_str);
+
+/**
+ * 3DES and DES encryption OIDs
+ */
+static u_char ASN1_3des_ede_cbc_oid_str[] = {
+	0x06, 0x08,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x03, 0x07
+};
+
+static u_char ASN1_des_cbc_oid_str[] = {
+	0x06, 0x05,
+		  0x2B, 0x0E, 0x03, 0x02, 0x07
+};
+
+static const chunk_t ASN1_3des_ede_cbc_oid = 
+						chunk_from_buf(ASN1_3des_ede_cbc_oid_str);
+static const chunk_t ASN1_des_cbc_oid =
+						chunk_from_buf(ASN1_des_cbc_oid_str);
+
+/**
+ * PKCS#7 attribute type OIDs
+ */
+static u_char ASN1_contentType_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x03
+};
+
+static u_char ASN1_messageDigest_oid_str[] = {
+	0x06, 0x09,
+		  0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x09, 0x04
+};
+
+static const chunk_t ASN1_contentType_oid =
+						chunk_from_buf(ASN1_contentType_oid_str);
+static const chunk_t ASN1_messageDigest_oid =
+						chunk_from_buf(ASN1_messageDigest_oid_str);
+
+/**
+ * Implements pkcs7_contentInfo_t.destroy
+ */
+static void destroy(private_pkcs7_contentInfo_t *this)
+{
+	free(this);
+}
+
+/**
+ * Parse PKCS#7 ContentInfo object
+ */
+static bool pkcs7_parse_contentInfo(chunk_t blob, u_int level0, private_pkcs7_contentInfo_t *cInfo)
+{
+	asn1_ctx_t ctx;
+	chunk_t object;
+	u_int level;
+	int objectID = 0;
+
+	asn1_init(&ctx, blob, level0, FALSE, FALSE);
+
+	while (objectID < PKCS7_INFO_ROOF)
+	{
+		if (!extract_object(contentInfoObjects, &objectID, &object, &level, &ctx))
+		{
+			return FALSE;
+		}
+
+		if (objectID == PKCS7_INFO_TYPE)
+		{
+			cInfo->type = known_oid(object);
+			if (cInfo->type < OID_PKCS7_DATA
+			||  cInfo->type > OID_PKCS7_ENCRYPTED_DATA)
+			{
+				DBG1("unknown pkcs7 content type");
+				return FALSE;
+			}
+		}
+		else if (objectID == PKCS7_INFO_CONTENT)
+		{
+			cInfo->content = object;
+		}
+		objectID++;
+	}
+	return TRUE;
+}
+
+/*
+ * Described in header.
+ */
+pkcs7_contentInfo_t *pkcs7_contentInfo_create_from_chunk(chunk_t chunk, u_int level)
+{
+	private_pkcs7_contentInfo_t *this = malloc_thing(private_pkcs7_contentInfo_t);
+	
+	/* initialize */
+	this->type = OID_UNKNOWN;
+	this->content = chunk_empty;
+
+	/*public functions */
+	this->public.destroy = (void (*) (pkcs7_contentInfo_t*))destroy;
+
+	if (!pkcs7_parse_contentInfo(chunk, level, this))
+	{
+		destroy(this);
+		return NULL;
+	}
+	return &this->public;
+}
+
+/**
+ * Parse a PKCS#7 signedData object
+ */
+bool pkcs7_parse_signedData(chunk_t blob, pkcs7_contentInfo_t *data, x509_t **cert,
+							chunk_t *attributes, const x509_t *cacert)
+{
+	u_char buf[BUF_LEN];
+	asn1_ctx_t ctx;
+	chunk_t object;
+	u_int level;
+	int digest_alg = OID_UNKNOWN;
+	int enc_alg    = OID_UNKNOWN;
+	int signerInfos = 0;
+	int objectID = 0;
+
+	private_pkcs7_contentInfo_t cInfo;
+	chunk_t encrypted_digest = chunk_empty;
+
+	if (!pkcs7_parse_contentInfo(blob, 0, &cInfo))
+	{
+		return FALSE;
+	}
+	if (cInfo.type != OID_PKCS7_SIGNED_DATA)
+	{
+		DBG1("pkcs7 content type is not signedData");
+		return FALSE;
+	}
+
+	asn1_init(&ctx, cInfo.content, 2, FALSE, FALSE);
+
+	while (objectID < PKCS7_SIGNED_ROOF)
+	{
+		if (!extract_object(signedDataObjects, &objectID, &object, &level, &ctx))
+		{
+			return FALSE;
+		}
+
+		switch (objectID)
+		{
+			case PKCS7_DIGEST_ALG:
+				digest_alg = parse_algorithmIdentifier(object, level, NULL);
+				break;
+			case PKCS7_SIGNED_CONTENT_INFO:
+				if (data != NULL)
+				{
+					pkcs7_parse_contentInfo(object, level, data);
+				}
+				break;
+			case PKCS7_SIGNED_CERT:
+				if (cert != NULL)
+				{
+					chunk_t cert_blob;
+
+					x509_t *newcert = alloc_thing(x509_t, "pkcs7 wrapped x509cert");
+
+					clonetochunk(cert_blob, object.ptr, object.len, "pkcs7 cert blob");
+					*newcert = empty_x509cert;
+
+					DBG2("parsing pkcs7-wrapped certificate");
+					if (parse_x509cert(cert_blob, level+1, newcert))
+					{
+						newcert->next = *cert;
+						*cert = newcert;
+					}
+					else
+					{
+						newcert->destroy(newcert);
+					}
+				}
+				break;
+			case PKCS7_SIGNER_INFO:
+				signerInfos++;
+				DBG2("  signer #%d", signerInfos);
+				break;
+			case PKCS7_SIGNED_ISSUER:
+				{
+					identification_t *issuer;
+
+					issuer = identification_create_from_encoding(ID_DER_ASN1_DN, object);
+					DBG2("  '%D'", issuer);
+					issuer->destroy(issuer);
+				}
+				break;
+			case PKCS7_AUTH_ATTRIBUTES:
+				if (attributes != NULL)
+				{
+					*attributes = object;
+					*attributes->ptr = ASN1_SET;
+				}
+				break;
+			case PKCS7_DIGEST_ALGORITHM:
+				digest_alg = parse_algorithmIdentifier(object, level, NULL);
+				break;
+			case PKCS7_DIGEST_ENC_ALGORITHM:
+				enc_alg = parse_algorithmIdentifier(object, level, NULL);
+				break;
+			case PKCS7_ENCRYPTED_DIGEST:
+				encrypted_digest = object;
+		}
+		objectID++;
+	}
+
+	/* check the signature only if a cacert is available */
+	if (cacert != NULL)
+	{
+		if (signerInfos == 0)
+		{
+			DBG1("no signerInfo object found");
+			return FALSE;
+		}
+		else if (signerInfos > 1)
+		{
+			DBG1("more than one signerInfo object found");
+		return FALSE;
+		}
+		if (attributes->ptr == NULL)
+		{
+			DBG1("no authenticatedAttributes object found");
+			return FALSE;
+		}
+		if (!check_signature(*attributes, encrypted_digest, digest_alg
+		, enc_alg, cacert))
+		{
+			DBG1("invalid signature");
+			return FALSE;
+		}
+		else
+		{
+			DBG2("signature is valid");
+		}
+	}
+	return TRUE;
+}
+
+/**
+ * Parse a PKCS#7 envelopedData object
+ */
+bool pkcs7_parse_envelopedData(chunk_t blob, chunk_t *data,
+							   chunk_t serialNumber,
+							   const RSA_private_key_t *key)
+{
+	asn1_ctx_t ctx;
+	chunk_t object;
+	chunk_t iv                = empty_chunk;
+	chunk_t symmetric_key     = empty_chunk;
+	chunk_t encrypted_content = empty_chunk;
+
+	u_char buf[BUF_LEN];
+	u_int level;
+	u_int total_keys = 3;
+	int enc_alg         = OID_UNKNOWN;
+	int content_enc_alg = OID_UNKNOWN;
+	int objectID = 0;
+
+	contentInfo_t cInfo = empty_contentInfo;
+	*data = empty_chunk;
+
+	if (!pkcs7_pkcs7_parse_contentInfo(blob, 0, &cInfo))
+	{
+		goto failed;
+	}
+	if (cInfo.type != OID_PKCS7_ENVELOPED_DATA)
+	{
+		DBG1("pkcs7 content type is not envelopedData");
+		goto failed;
+	}
+
+	asn1_init(&ctx, cInfo.content, 2, FALSE, DBG_RAW);
+
+	while (objectID < PKCS7_ENVELOPED_ROOF)
+	{
+		if (!extract_object(envelopedDataObjects, &objectID, &object, &level, &ctx))
+		{
+			goto failed;
+		}
+
+		switch (objectID)
+		{
+			case PKCS7_ENVELOPED_VERSION:
+				if (*object.ptr != 0)
+				{
+					DBG1("envelopedData version is not 0");
+					goto failed;
+				}
+				break;
+			case PKCS7_RECIPIENT_INFO_VERSION:
+				if (*object.ptr != 0)
+				{
+					DBG1("recipient info version is not 0");
+					goto failed;
+				}
+				break;
+			case PKCS7_ISSUER:
+				{
+					identification_t *issuer;
+
+					issuer = identification_create_from_encoding(ID_DER_ASN1_DN, object);
+					DBG2("  '%D'", issuer);
+					issuer->destroy(issuer);
+				}
+				break;
+			case PKCS7_SERIAL_NUMBER:
+				if (!chunk_equals(serialNumber, object))
+				{
+					DBG1("serial numbers do not match");
+					goto failed;
+				}
+				break;
+			case PKCS7_ENCRYPTION_ALG:
+				enc_alg = parse_algorithmIdentifier(object, level, NULL);
+				if (enc_alg != OID_RSA_ENCRYPTION)
+				{
+					DBG1("only rsa encryption supported");
+					goto failed;
+				}
+				break;
+			case PKCS7_ENCRYPTED_KEY:
+				if (!RSA_decrypt(key, object, &symmetric_key))
+				{
+					DBG1("symmetric key could not be decrypted with rsa");
+					goto failed;
+				}
+				DBG4("symmetric key : %B", &symmetric_key);
+				break;
+			case PKCS7_CONTENT_TYPE:
+				if (known_oid(object) != OID_PKCS7_DATA)
+				{
+					DBG1("encrypted content not of type pkcs7 data");
+		 			goto failed;
+				}
+				break;
+			case PKCS7_CONTENT_ENC_ALGORITHM:
+				content_enc_alg = parse_algorithmIdentifier(object, level, &iv);
+
+				switch (content_enc_alg)
+				{
+					case OID_DES_CBC:
+						total_keys = 1;
+						break;
+					case OID_3DES_EDE_CBC:
+						total_keys = 3;
+						break;
+					default:
+						DBG1("Only DES and 3DES supported for symmetric encryption");
+						goto failed;
+				}
+				if (symmetric_key.len != (total_keys * DES_CBC_BLOCK_SIZE))
+				{
+					DBG1("key length is not %d", (total_keys * DES_CBC_BLOCK_SIZE));
+					goto failed;
+				}
+				if (!parse_asn1_simple_object(&iv, ASN1_OCTET_STRING, level+1, "IV"))
+				{
+					DBG1("IV could not be parsed");
+					goto failed;
+				}
+				if (iv.len != DES_CBC_BLOCK_SIZE)
+				{
+					plog("IV has wrong length");
+					goto failed;
+				}
+				break;
+			case PKCS7_ENCRYPTED_CONTENT:
+				encrypted_content = object;
+				break;
+		}
+		objectID++;
+	}
+
+	/* decrypt the content */
+	{
+		u_int i;
+		des_cblock des_key[3], des_iv;
+		des_key_schedule key_s[3];
+
+		memcpy((char *)des_key, symmetric_key.ptr, symmetric_key.len);
+		memcpy((char *)des_iv, iv.ptr, iv.len);
+
+		for (i = 0; i < total_keys; i++)
+		{
+			if (des_set_key(&des_key[i], key_s[i]))
+			{
+				plog("des key schedule failed");
+				goto failed;
+			}
+		}
+
+		data->len = encrypted_content.len;
+		data->ptr = alloc_bytes(data->len, "decrypted data");
+
+		switch (content_enc_alg)
+		{
+			case OID_DES_CBC:
+				des_cbc_encrypt((des_cblock*)encrypted_content.ptr
+					, (des_cblock*)data->ptr, data->len
+					, key_s[0], &des_iv, DES_DECRYPT);
+				break;
+			case OID_3DES_EDE_CBC:
+				des_ede3_cbc_encrypt( (des_cblock*)encrypted_content.ptr
+					, (des_cblock*)data->ptr, data->len
+					, key_s[0], key_s[1], key_s[2]
+					, &des_iv, DES_DECRYPT);
+		}
+		DBG4("decrypted content with padding: %B", data);
+	}
+
+	/* remove the padding */
+	{
+		u_char *pos = data->ptr + data->len - 1;
+		u_char pattern = *pos;
+		size_t padding = pattern;
+
+		if (padding > data->len)
+		{
+			DBG1("padding greater than data length");
+			goto failed;
+		}
+		data->len -= padding;
+
+		while (padding-- > 0)
+		{
+			if (*pos-- != pattern)
+			{
+				DBG1("wrong padding pattern");
+				goto failed;
+			}
+		}
+	}
+	free(symmetric_key.ptr);
+	return TRUE;
+
+failed:
+	free(symmetric_key.ptr);
+	pfreeany(data->ptr);
+	return FALSE;
+}
+
+/**
+ * @brief Builds a contentType attribute
+ *
+ * @return ASN.1 encoded contentType attribute
+ */
+chunk_t pkcs7_contentType_attribute(void)
+{
+	return asn1_wrap(ASN1_SEQUENCE, "cm"
+			, ASN1_contentType_oid
+			, asn1_simple_object(ASN1_SET, ASN1_pkcs7_data_oid));
+}
+
+/**
+ * @brief Builds a messageDigest attribute
+ * 
+ * 
+ * @param[in] blob content to create digest of
+ * @param[in] digest_alg digest algorithm to be used
+ * @return ASN.1 encoded messageDigest attribute
+ * 
+ */
+chunk_t pkcs7_messageDigest_attribute(chunk_t content, int digest_alg)
+{
+	u_char digest_buf[MAX_DIGEST_LEN];
+	chunk_t digest = { digest_buf, MAX_DIGEST_LEN };
+
+	compute_digest(content, digest_alg, &digest);
+
+	return asn1_wrap(ASN1_SEQUENCE, "cm"
+			, ASN1_messageDigest_oid
+			, asn1_wrap(ASN1_SET, "m"
+			    , asn1_simple_object(ASN1_OCTET_STRING, digest)
+			  )
+		   );
+}
+
+/**
+ * build a DER-encoded contentInfo object
+ */
+static chunk_t pkcs7_build_contentInfo(contentInfo_t *cInfo)
+{
+	chunk_t content_type;
+
+	/* select DER-encoded OID for pkcs7 contentInfo type */
+	switch(cInfo->type)
+	{
+		case OID_PKCS7_DATA:
+			content_type = ASN1_pkcs7_data_oid;
+			break;
+		case OID_PKCS7_SIGNED_DATA:
+			content_type = ASN1_pkcs7_signed_data_oid;
+			break;
+		case OID_PKCS7_ENVELOPED_DATA:
+			content_type = ASN1_pkcs7_enveloped_data_oid;
+			break;
+		case OID_PKCS7_SIGNED_ENVELOPED_DATA:
+			content_type = ASN1_pkcs7_signed_enveloped_data_oid;
+			break;
+		case OID_PKCS7_DIGESTED_DATA:
+			content_type = ASN1_pkcs7_digested_data_oid;
+			break;
+		case OID_PKCS7_ENCRYPTED_DATA:
+			content_type = ASN1_pkcs7_encrypted_data_oid;
+			break;
+		case OID_UNKNOWN:
+		default:
+			DBG1("invalid pkcs7 contentInfo type");
+			return chunk_empty;
+    }
+
+	return (cInfo->content.ptr == NULL)
+		? asn1_simple_object(ASN1_SEQUENCE, content_type)
+		: asn1_wrap(ASN1_SEQUENCE, "cm"
+			, content_type
+			, asn1_simple_object(ASN1_CONTEXT_C_0, cInfo->content)
+		  );
+}
+
+/**
+ * build issuerAndSerialNumber object
+ */
+chunk_t pkcs7_build_issuerAndSerialNumber(const x509_t *cert)
+{
+	return asn1_wrap(ASN1_SEQUENCE, "cm"
+			, cert->issuer
+			, asn1_simple_object(ASN1_INTEGER, cert->serialNumber));
+}
+
+/**
+ * create a signed pkcs7 contentInfo object
+ */
+chunk_t pkcs7_build_signedData(chunk_t data, chunk_t attributes, const x509_t *cert,
+							   int digest_alg, const RSA_private_key_t *key)
+{
+	contentInfo_t pkcs7Data, signedData;
+	chunk_t authenticatedAttributes, encryptedDigest, signerInfo, cInfo;
+
+	chunk_t digestAlgorithm = asn1_algorithmIdentifier(digest_alg);
+
+	if (attributes.ptr != NULL)
+	{
+		encryptedDigest = pkcs1_build_signature(attributes, digest_alg
+				, key, FALSE);
+		clonetochunk(authenticatedAttributes, attributes.ptr, attributes.len
+			, "authenticatedAttributes");
+		*authenticatedAttributes.ptr = ASN1_CONTEXT_C_0;
+	}
+	else
+	{
+		encryptedDigest = (data.ptr == NULL)? empty_chunk
+			: pkcs1_build_signature(data, digest_alg, key, FALSE);
+		authenticatedAttributes = empty_chunk;
+	}
+
+	signerInfo = asn1_wrap(ASN1_SEQUENCE, "cmcmcm"
+			, ASN1_INTEGER_1
+			, pkcs7_build_issuerAndSerialNumber(cert)
+			, digestAlgorithm
+			, authenticatedAttributes
+			, ASN1_rsaEncryption_id
+			, encryptedDigest);
+
+	pkcs7Data.type    = OID_PKCS7_DATA;
+	pkcs7Data.content = (data.ptr == NULL)? empty_chunk
+			: asn1_simple_object(ASN1_OCTET_STRING, data);
+
+	signedData.type = OID_PKCS7_SIGNED_DATA;
+	signedData.content = asn1_wrap(ASN1_SEQUENCE, "cmmmm"
+			, ASN1_INTEGER_1
+			, asn1_simple_object(ASN1_SET, digestAlgorithm)
+			, pkcs7_build_contentInfo(&pkcs7Data)
+			, asn1_simple_object(ASN1_CONTEXT_C_0, cert->certificate)
+			, asn1_wrap(ASN1_SET, "m", signerInfo));
+
+	cInfo = pkcs7_build_contentInfo(&signedData);
+	DBG3("signedData: %B", &cInfo);
+
+	free(pkcs7Data.content.ptr);
+	free(signedData.content.ptr);
+	return cInfo;
+}
+
+/**
+ * create a symmetrically encrypted pkcs7 contentInfo object
+ */
+chunk_t pkcs7_build_envelopedData(chunk_t data, const x509_t *cert, int cipher)
+{
+	bool des_check_key_save;
+	des_key_schedule ks[3];
+	des_cblock key[3], des_iv, des_iv_buf;
+
+	chunk_t iv = { (u_char *)des_iv_buf, DES_CBC_BLOCK_SIZE };
+	chunk_t out;
+	chunk_t cipher_oid;
+
+	u_int total_keys, i;
+	size_t padding = pad_up(data.len, DES_CBC_BLOCK_SIZE);
+
+	RSA_public_key_t public_key;
+
+	init_RSA_public_key(&public_key, cert->publicExponent
+				   , cert->modulus);
+
+	if (padding == 0)
+	{
+		padding += DES_CBC_BLOCK_SIZE;
+	}
+
+	out.len = data.len + padding;
+	out.ptr = alloc_bytes(out.len, "DES-encrypted output");
+
+	DBG2("padding %d bytes of data to multiple DES block size of %d bytes"
+			, (int)data.len, (int)out.len);
+
+	/* copy data */
+	memcpy(out.ptr, data.ptr, data.len);
+	/* append padding */
+	memset(out.ptr + data.len, padding, padding);
+
+	DBG3("padded unencrypted data: %B", &out);
+
+	/* select OID and keylength for specified cipher */
+	switch (cipher)
+	{
+		case OID_DES_CBC:
+			total_keys = 1;
+			cipher_oid = ASN1_des_cbc_oid;
+			break;
+		case OID_3DES_EDE_CBC:
+		default:
+		total_keys = 3;
+		cipher_oid = ASN1_3des_ede_cbc_oid;
+	}
+	DBG2("pkcs7 encryption cipher: %s", oid_names[cipher].name);
+
+	/* generate a strong random key for DES/3DES */
+	des_check_key_save = des_check_key;
+	des_check_key = TRUE;
+	for (i = 0; i < total_keys;i++)
+	{
+		for (;;)
+		{
+			get_rnd_bytes((char*)key[i], DES_CBC_BLOCK_SIZE);
+			des_set_odd_parity(&key[i]);
+			if (!des_set_key(&key[i], ks[i]))
+			{
+				break;
+				plog("weak DES key discarded - we try again");
+			}
+		}
+		/* TODO DBG4("DES key: %#B", key[i], 8) */
+    }
+	des_check_key = des_check_key_save;
+
+	/* generate an iv for DES/3DES CBC */
+	get_rnd_bytes(des_iv, DES_CBC_BLOCK_SIZE);
+	memcpy(iv.ptr, des_iv, DES_CBC_BLOCK_SIZE);
+	DBG3("DES IV : %#B", &iv);
+
+	/* encryption using specified cipher */
+	switch (cipher)
+	{
+		case OID_DES_CBC:
+			des_cbc_encrypt((des_cblock*)out.ptr, (des_cblock*)out.ptr, out.len
+		    	   , ks[0], &des_iv, DES_ENCRYPT);
+			break;
+		case OID_3DES_EDE_CBC:
+		default:
+			des_ede3_cbc_encrypt((des_cblock*)out.ptr, (des_cblock*)out.ptr, out.len
+				    , ks[0], ks[1], ks[2], &des_iv, DES_ENCRYPT);	
+	}
+	DBG3(("Encrypted data: %B", &out);
+	
+	/* build pkcs7 enveloped data object */ 
+	{
+		chunk_t contentEncryptionAlgorithm = asn1_wrap(ASN1_SEQUENCE, "cm"
+				, cipher_oid
+				, asn1_simple_object(ASN1_OCTET_STRING, iv));
+	
+		chunk_t encryptedContentInfo = asn1_wrap(ASN1_SEQUENCE, "cmm"
+				, ASN1_pkcs7_data_oid
+				, contentEncryptionAlgorithm
+				, asn1_wrap(ASN1_CONTEXT_S_0, "m", out));
+
+		chunk_t plainKey = { (u_char *)key, DES_CBC_BLOCK_SIZE * total_keys };
+
+		chunk_t encryptedKey = asn1_wrap(ASN1_OCTET_STRING, "m"
+				, RSA_encrypt(&public_key, plainKey));
+
+		chunk_t recipientInfo = asn1_wrap(ASN1_SEQUENCE, "cmcm"
+				, ASN1_INTEGER_0
+				, pkcs7_build_issuerAndSerialNumber(cert)
+				, ASN1_rsaEncryption_id
+				, encryptedKey);
+
+		chunk_t cInfo;
+		contentInfo_t envelopedData;
+
+		envelopedData.type = OID_PKCS7_ENVELOPED_DATA;
+		envelopedData.content = asn1_wrap(ASN1_SEQUENCE, "cmm"
+				, ASN1_INTEGER_0
+				, asn1_wrap(ASN1_SET, "m", recipientInfo)
+				, encryptedContentInfo);
+
+		cInfo = pkcs7_build_contentInfo(&envelopedData);
+		DBG3("envelopedData: %B", &cInfo);
+
+		free_RSA_public_content(&public_key);
+		free(envelopedData.content.ptr);
+		return cInfo;
+	}
+}
diff --git a/src/libstrongswan/crypto/pkcs7.h b/src/libstrongswan/crypto/pkcs7.h
new file mode 100644
index 000000000..a986044d9
--- /dev/null
+++ b/src/libstrongswan/crypto/pkcs7.h
@@ -0,0 +1,80 @@
+/**
+ * @file pkcs7.h
+ * 
+ * @brief Interface of pkcs7_contentInfo_t.
+ * 
+ */
+
+/*
+ * Copyright (C) 2005 Jan Hutter, Martin Willi
+ * Copyright (C) 2002-2007 Andreas Steffen
+ *
+ * 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.
+ *
+ * RCSID $Id$
+ */
+
+#ifndef _PKCS7_H
+#define _PKCS7_H
+
+typedef struct pkcs7_contentInfo_t pkcs7_contentInfo_t;
+
+#include <library.h>
+#include <crypto/x509.h>
+#include <crypto/rsa/rsa_private_key.h>
+
+/* Access structure for a PKCS#7 ContentInfo object */
+
+
+/**
+ * @brief PKCS#7 ContentInfo object.
+ * 
+ * @b Constructors:
+ *  -pkcs7_create_from_chunk()
+ *
+ * @ingroup crypto
+ */
+struct pkcs7_contentInfo_t {
+	/**
+	 * @brief Is contentInfo object of type signedData?.
+	 * 
+	 * @param this			calling object
+	 * @return				TRUE if of type signedData
+	 */
+	bool (*is_signedData) (pkcs7_contentInfo_t *this);
+
+	/**
+	 * @brief Is contentInfo object of type envelopedData?.
+	 * 
+	 * @param this			calling object
+	 * @return				TRUE if of type envelopedData
+	 */
+	bool (*is_envelopedData) (pkcs7_contentInfo_t *this);
+
+	/**
+	 * @brief Destroys the contentInfo object.
+	 * 
+	 * @param this			contentInfo object to destroy
+	 */
+	void (*destroy) (pkcs7_contentInfo_t *this);
+};
+
+extern chunk_t pkcs7_contentType_attribute(void);
+extern chunk_t pkcs7_messageDigest_attribute(chunk_t content, int digest_alg);
+extern chunk_t pkcs7_build_issuerAndSerialNumber(const x509_t *cert);
+extern chunk_t pkcs7_build_signedData(chunk_t data, chunk_t attributes
+    ,const x509_t *cert, int digest_alg, const rsa_private_key_t *key);
+extern chunk_t pkcs7_build_envelopedData(chunk_t data, const x509_t *cert
+    , int cipher);
+
+#endif /* _PKCS7_H */
diff --git a/src/libstrongswan/library.h b/src/libstrongswan/library.h
index b091f2601..bbe863fa0 100644
--- a/src/libstrongswan/library.h
+++ b/src/libstrongswan/library.h
@@ -18,6 +18,8 @@
  * 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.
+ *
+ * RCSID $Id$
  */
 
 #ifndef LIBRARY_H_
@@ -129,6 +131,11 @@
 #define streq(x,y) (strcmp(x, y) == 0)
 
 /**
+ * Macro compares two strings for equality
+ */
+#define strneq(x,y,len) (strncmp(x, y, len) == 0)
+
+/**
  * Macro compares two binary blobs for equality
  */
 #define memeq(x,y,len) (memcmp(x, y, len) == 0)