FreeRDP/libfreerdp-core/certificate.c

360 lines
8.5 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Client
* Certificate Handling
*
* Copyright 2011 Marc-Andre Moreau <marcandre.moreau@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "certificate.h"
/**
*
* X.509 Certificate Structure
*
* Certificate ::= SEQUENCE
* {
* tbsCertificate TBSCertificate,
* signatureAlgorithm AlgorithmIdentifier,
* signatureValue BIT_STRING
* }
*
* TBSCertificate ::= SEQUENCE
* {
* version [0] EXPLICIT Version DEFAULT v1,
* serialNumber CertificateSerialNumber,
* signature AlgorithmIdentifier,
* issuer Name,
* validity Validity,
* subject Name,
* subjectPublicKeyInfo SubjectPublicKeyInfo,
* issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
* subjectUniqueId [2] IMPLICIT UniqueIdentifier OPTIONAL,
* extensions [3] EXPLICIT Extensions OPTIONAL
* }
*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*
* CertificateSerialNumber ::= INTEGER
*
* AlgorithmIdentifier ::= SEQUENCE
* {
* algorithm OBJECT_IDENTIFIER,
* parameters ANY DEFINED BY algorithm OPTIONAL
* }
*
* Name ::= CHOICE { RDNSequence }
*
* RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
*
* RelativeDistinguishedName ::= SET OF AttributeTypeAndValue
*
* AttributeTypeAndValue ::= SEQUENCE
* {
* type AttributeType,
* value AttributeValue
* }
*
* AttributeType ::= OBJECT_IDENTIFIER
*
* AttributeValue ::= ANY DEFINED BY AttributeType
*
* Validity ::= SEQUENCE
* {
* notBefore Time,
* notAfter Time
* }
*
* Time ::= CHOICE
* {
* utcTime UTCTime,
* generalTime GeneralizedTime
* }
*
* UniqueIdentifier ::= BIT_STRING
*
* SubjectPublicKeyInfo ::= SEQUENCE
* {
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT_STRING
* }
*
* RSAPublicKey ::= SEQUENCE
* {
* modulus INTEGER
* publicExponent INTEGER
* }
*
* Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension
*
* Extension ::= SEQUENCE
* {
* extnID OBJECT_IDENTIFIER
* critical BOOLEAN DEFAULT FALSE,
* extnValue OCTET_STRING
* }
*
*/
/**
* Read X.509 Certificate
* @param certificate certificate module
* @param cert X.509 certificate
*/
void certificate_read_x509_certificate(CERT_BLOB* cert, CERT_INFO* info)
{
STREAM* s;
int length;
uint8 padding;
uint32 version;
uint8 exponent[4];
int modulus_length;
int exponent_length;
s = stream_new(0);
s->p = s->data = cert->data;
ber_read_sequence_tag(s, &length); /* Certificate (SEQUENCE) */
ber_read_sequence_tag(s, &length); /* TBSCertificate (SEQUENCE) */
/* Explicit Contextual Tag [0] */
ber_read_contextual_tag(s, 0, &length, True);
ber_read_integer(s, &version); /* version (INTEGER) */
version++;
/* serialNumber */
ber_read_integer(s, NULL); /* CertificateSerialNumber (INTEGER) */
/* signature */
ber_read_sequence_tag(s, &length); /* AlgorithmIdentifier (SEQUENCE) */
stream_seek(s, length);
/* issuer */
ber_read_sequence_tag(s, &length); /* Name (SEQUENCE) */
stream_seek(s, length);
/* validity */
ber_read_sequence_tag(s, &length); /* Validity (SEQUENCE) */
stream_seek(s, length);
/* subject */
ber_read_sequence_tag(s, &length); /* Name (SEQUENCE) */
stream_seek(s, length);
/* subjectPublicKeyInfo */
ber_read_sequence_tag(s, &length); /* SubjectPublicKeyInfo (SEQUENCE) */
/* subjectPublicKeyInfo::AlgorithmIdentifier */
ber_read_sequence_tag(s, &length); /* AlgorithmIdentifier (SEQUENCE) */
stream_seek(s, length);
/* subjectPublicKeyInfo::subjectPublicKey */
ber_read_bit_string(s, &length, &padding); /* BIT_STRING */
/* RSAPublicKey (SEQUENCE) */
ber_read_sequence_tag(s, &length); /* SEQUENCE */
ber_read_integer_length(s, &modulus_length); /* modulus (INTEGER) */
/* skip zero padding, if any */
do
{
stream_peek_uint8(s, padding);
if (padding == 0)
{
stream_seek(s, 1);
modulus_length--;
}
}
while (padding == 0);
freerdp_blob_alloc(&info->modulus, modulus_length);
stream_read(s, info->modulus.data, modulus_length);
ber_read_integer_length(s, &exponent_length); /* publicExponent (INTEGER) */
stream_read(s, &info->exponent[4 - exponent_length], exponent_length);
}
/**
* Instantiate new X.509 Certificate Chain.
* @param count certificate chain count
* @return new X.509 certificate chain
*/
X509_CERT_CHAIN* certificate_new_x509_certificate_chain(uint32 count)
{
X509_CERT_CHAIN* x509_cert_chain;
x509_cert_chain = (X509_CERT_CHAIN*) xmalloc(sizeof(X509_CERT_CHAIN));
x509_cert_chain->count = count;
x509_cert_chain->array = (CERT_BLOB*) xzalloc(sizeof(CERT_BLOB) * count);
return x509_cert_chain;
}
/**
* Free X.509 Certificate Chain.
* @param x509_cert_chain X.509 certificate chain to be freed
*/
void certificate_free_x509_certificate_chain(X509_CERT_CHAIN* x509_cert_chain)
{
int i;
if (x509_cert_chain == NULL)
return;
for (i = 0; i < x509_cert_chain->count; i++)
{
if (x509_cert_chain->array[i].data != NULL)
xfree(x509_cert_chain->array[i].data);
}
xfree(x509_cert_chain);
}
/**
* Read a Server Proprietary Certificate.\n
* @param certificate certificate module
* @param s stream
*/
void certificate_read_server_proprietary_certificate(rdpCertificate* certificate, STREAM* s)
{
printf("Server Proprietary Certificate\n");
}
/**
* Read an X.509 Certificate Chain.\n
* @param certificate certificate module
* @param s stream
*/
void certificate_read_server_x509_certificate_chain(rdpCertificate* certificate, STREAM* s)
{
int i;
uint32 certLength;
uint32 numCertBlobs;
DEBUG_CERTIFICATE("Server X.509 Certificate Chain");
stream_read_uint32(s, numCertBlobs); /* numCertBlobs */
certificate->x509_cert_chain = certificate_new_x509_certificate_chain(numCertBlobs);
for (i = 0; i < numCertBlobs; i++)
{
stream_read_uint32(s, certLength);
DEBUG_CERTIFICATE("\nX.509 Certificate #%d, length:%d", i + 1, certLength);
certificate->x509_cert_chain->array[i].data = (uint8*) xmalloc(certLength);
stream_read(s, certificate->x509_cert_chain->array[i].data, certLength);
certificate->x509_cert_chain->array[i].length = certLength;
if (numCertBlobs - i == 2)
{
CERT_INFO cert_info;
DEBUG_CERTIFICATE("License Server Certificate");
certificate_read_x509_certificate(&certificate->x509_cert_chain->array[i], &cert_info);
DEBUG_LICENSE("modulus length:%d", cert_info.modulus.length);
}
else if (numCertBlobs - i == 1)
{
DEBUG_CERTIFICATE("Terminal Server Certificate");
certificate_read_x509_certificate(&certificate->x509_cert_chain->array[i], &certificate->cert_info);
DEBUG_CERTIFICATE("modulus length:%d", certificate->cert_info.modulus.length);
}
}
}
/**
* Read a Server Certificate.\n
* @param certificate certificate module
* @param server_cert server certificate
* @param length certificate length
*/
void certificate_read_server_certificate(rdpCertificate* certificate, uint8* server_cert, int length)
{
STREAM* s;
uint32 dwVersion;
s = stream_new(0);
s->p = s->data = server_cert;
if (length < 1)
{
printf("null server certificate\n");
return;
}
stream_read_uint32(s, dwVersion); /* dwVersion (4 bytes) */
switch (dwVersion & CERT_CHAIN_VERSION_MASK)
{
case CERT_CHAIN_VERSION_1:
certificate_read_server_proprietary_certificate(certificate, s);
break;
case CERT_CHAIN_VERSION_2:
certificate_read_server_x509_certificate_chain(certificate, s);
break;
default:
printf("invalid certificate chain version:%d\n", dwVersion & CERT_CHAIN_VERSION_MASK);
break;
}
}
/**
* Instantiate new certificate module.\n
* @param rdp RDP module
* @return new certificate module
*/
rdpCertificate* certificate_new(rdpRdp* rdp)
{
rdpCertificate* certificate;
certificate = (rdpCertificate*) xzalloc(sizeof(rdpCertificate));
if (certificate != NULL)
{
certificate->rdp = rdp;
certificate->x509_cert_chain = NULL;
}
return certificate;
}
/**
* Free certificate module.
* @param certificate certificate module to be freed
*/
void certificate_free(rdpCertificate* certificate)
{
if (certificate != NULL)
{
certificate_free_x509_certificate_chain(certificate->x509_cert_chain);
xfree(certificate);
}
}