blob: 79e2ad56b7d749ea05682bc3db4836d819de8221 [file] [log] [blame]
/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
// Handling of certificates and keypairs for SSLStreamAdapter's peer mode.
#include "rtc_base/sslidentity.h"
#include <ctime>
#include <string>
#include <utility>
#include "rtc_base/base64.h"
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
#include "rtc_base/opensslidentity.h"
#include "rtc_base/ptr_util.h"
#include "rtc_base/sslfingerprint.h"
namespace rtc {
const char kPemTypeCertificate[] = "CERTIFICATE";
const char kPemTypeRsaPrivateKey[] = "RSA PRIVATE KEY";
const char kPemTypeEcPrivateKey[] = "EC PRIVATE KEY";
SSLCertificateStats::SSLCertificateStats(
std::string&& fingerprint,
std::string&& fingerprint_algorithm,
std::string&& base64_certificate,
std::unique_ptr<SSLCertificateStats>&& issuer)
: fingerprint(std::move(fingerprint)),
fingerprint_algorithm(std::move(fingerprint_algorithm)),
base64_certificate(std::move(base64_certificate)),
issuer(std::move(issuer)) {
}
SSLCertificateStats::~SSLCertificateStats() {
}
std::unique_ptr<SSLCertificateStats> SSLCertificate::GetStats() const {
// We have a certificate and optionally a chain of certificates. This forms a
// linked list, starting with |this|, then the first element of |chain| and
// ending with the last element of |chain|. The "issuer" of a certificate is
// the next certificate in the chain. Stats are produced for each certificate
// in the list. Here, the "issuer" is the issuer's stats.
std::unique_ptr<SSLCertChain> chain = GetChain();
std::unique_ptr<SSLCertificateStats> issuer;
if (chain) {
// The loop runs in reverse so that the |issuer| is known before the
// |cert|'s stats.
for (ptrdiff_t i = chain->GetSize() - 1; i >= 0; --i) {
const SSLCertificate* cert = &chain->Get(i);
issuer = cert->GetStats(std::move(issuer));
}
}
return GetStats(std::move(issuer));
}
std::unique_ptr<SSLCertificate> SSLCertificate::GetUniqueReference() const {
return WrapUnique(GetReference());
}
std::unique_ptr<SSLCertificateStats> SSLCertificate::GetStats(
std::unique_ptr<SSLCertificateStats> issuer) const {
// TODO(bemasc): Move this computation to a helper class that caches these
// values to reduce CPU use in |StatsCollector::GetStats|. This will require
// adding a fast |SSLCertificate::Equals| to detect certificate changes.
std::string digest_algorithm;
if (!GetSignatureDigestAlgorithm(&digest_algorithm))
return nullptr;
// |SSLFingerprint::Create| can fail if the algorithm returned by
// |SSLCertificate::GetSignatureDigestAlgorithm| is not supported by the
// implementation of |SSLCertificate::ComputeDigest|. This currently happens
// with MD5- and SHA-224-signed certificates when linked to libNSS.
std::unique_ptr<SSLFingerprint> ssl_fingerprint(
SSLFingerprint::Create(digest_algorithm, this));
if (!ssl_fingerprint)
return nullptr;
std::string fingerprint = ssl_fingerprint->GetRfc4572Fingerprint();
Buffer der_buffer;
ToDER(&der_buffer);
std::string der_base64;
Base64::EncodeFromArray(der_buffer.data(), der_buffer.size(), &der_base64);
return std::unique_ptr<SSLCertificateStats>(new SSLCertificateStats(
std::move(fingerprint),
std::move(digest_algorithm),
std::move(der_base64),
std::move(issuer)));
}
KeyParams::KeyParams(KeyType key_type) {
if (key_type == KT_ECDSA) {
type_ = KT_ECDSA;
params_.curve = EC_NIST_P256;
} else if (key_type == KT_RSA) {
type_ = KT_RSA;
params_.rsa.mod_size = kRsaDefaultModSize;
params_.rsa.pub_exp = kRsaDefaultExponent;
} else {
RTC_NOTREACHED();
}
}
// static
KeyParams KeyParams::RSA(int mod_size, int pub_exp) {
KeyParams kt(KT_RSA);
kt.params_.rsa.mod_size = mod_size;
kt.params_.rsa.pub_exp = pub_exp;
return kt;
}
// static
KeyParams KeyParams::ECDSA(ECCurve curve) {
KeyParams kt(KT_ECDSA);
kt.params_.curve = curve;
return kt;
}
bool KeyParams::IsValid() const {
if (type_ == KT_RSA) {
return (params_.rsa.mod_size >= kRsaMinModSize &&
params_.rsa.mod_size <= kRsaMaxModSize &&
params_.rsa.pub_exp > params_.rsa.mod_size);
} else if (type_ == KT_ECDSA) {
return (params_.curve == EC_NIST_P256);
}
return false;
}
RSAParams KeyParams::rsa_params() const {
RTC_DCHECK(type_ == KT_RSA);
return params_.rsa;
}
ECCurve KeyParams::ec_curve() const {
RTC_DCHECK(type_ == KT_ECDSA);
return params_.curve;
}
KeyType IntKeyTypeFamilyToKeyType(int key_type_family) {
return static_cast<KeyType>(key_type_family);
}
bool SSLIdentity::PemToDer(const std::string& pem_type,
const std::string& pem_string,
std::string* der) {
// Find the inner body. We need this to fulfill the contract of
// returning pem_length.
size_t header = pem_string.find("-----BEGIN " + pem_type + "-----");
if (header == std::string::npos)
return false;
size_t body = pem_string.find("\n", header);
if (body == std::string::npos)
return false;
size_t trailer = pem_string.find("-----END " + pem_type + "-----");
if (trailer == std::string::npos)
return false;
std::string inner = pem_string.substr(body + 1, trailer - (body + 1));
*der = Base64::Decode(inner, Base64::DO_PARSE_WHITE |
Base64::DO_PAD_ANY |
Base64::DO_TERM_BUFFER);
return true;
}
std::string SSLIdentity::DerToPem(const std::string& pem_type,
const unsigned char* data,
size_t length) {
std::stringstream result;
result << "-----BEGIN " << pem_type << "-----\n";
std::string b64_encoded;
Base64::EncodeFromArray(data, length, &b64_encoded);
// Divide the Base-64 encoded data into 64-character chunks, as per
// 4.3.2.4 of RFC 1421.
static const size_t kChunkSize = 64;
size_t chunks = (b64_encoded.size() + (kChunkSize - 1)) / kChunkSize;
for (size_t i = 0, chunk_offset = 0; i < chunks;
++i, chunk_offset += kChunkSize) {
result << b64_encoded.substr(chunk_offset, kChunkSize);
result << "\n";
}
result << "-----END " << pem_type << "-----\n";
return result.str();
}
SSLCertChain::SSLCertChain(std::vector<std::unique_ptr<SSLCertificate>> certs)
: certs_(std::move(certs)) {}
SSLCertChain::SSLCertChain(const std::vector<SSLCertificate*>& certs) {
RTC_DCHECK(!certs.empty());
certs_.resize(certs.size());
std::transform(
certs.begin(), certs.end(), certs_.begin(),
[](const SSLCertificate* cert) -> std::unique_ptr<SSLCertificate> {
return cert->GetUniqueReference();
});
}
SSLCertChain::SSLCertChain(const SSLCertificate* cert) {
certs_.push_back(cert->GetUniqueReference());
}
SSLCertChain::~SSLCertChain() {}
SSLCertChain* SSLCertChain::Copy() const {
std::vector<std::unique_ptr<SSLCertificate>> new_certs(certs_.size());
std::transform(certs_.begin(), certs_.end(), new_certs.begin(),
[](const std::unique_ptr<SSLCertificate>& cert)
-> std::unique_ptr<SSLCertificate> {
return cert->GetUniqueReference();
});
return new SSLCertChain(std::move(new_certs));
}
// static
SSLCertificate* SSLCertificate::FromPEMString(const std::string& pem_string) {
return OpenSSLCertificate::FromPEMString(pem_string);
}
// static
SSLIdentity* SSLIdentity::GenerateWithExpiration(const std::string& common_name,
const KeyParams& key_params,
time_t certificate_lifetime) {
return OpenSSLIdentity::GenerateWithExpiration(common_name, key_params,
certificate_lifetime);
}
// static
SSLIdentity* SSLIdentity::Generate(const std::string& common_name,
const KeyParams& key_params) {
return OpenSSLIdentity::GenerateWithExpiration(
common_name, key_params, kDefaultCertificateLifetimeInSeconds);
}
// static
SSLIdentity* SSLIdentity::Generate(const std::string& common_name,
KeyType key_type) {
return OpenSSLIdentity::GenerateWithExpiration(
common_name, KeyParams(key_type), kDefaultCertificateLifetimeInSeconds);
}
SSLIdentity* SSLIdentity::GenerateForTest(const SSLIdentityParams& params) {
return OpenSSLIdentity::GenerateForTest(params);
}
// static
SSLIdentity* SSLIdentity::FromPEMStrings(const std::string& private_key,
const std::string& certificate) {
return OpenSSLIdentity::FromPEMStrings(private_key, certificate);
}
bool operator==(const SSLIdentity& a, const SSLIdentity& b) {
return static_cast<const OpenSSLIdentity&>(a) ==
static_cast<const OpenSSLIdentity&>(b);
}
bool operator!=(const SSLIdentity& a, const SSLIdentity& b) {
return !(a == b);
}
// Read |n| bytes from ASN1 number string at *|pp| and return the numeric value.
// Update *|pp| and *|np| to reflect number of read bytes.
static inline int ASN1ReadInt(const unsigned char** pp, size_t* np, size_t n) {
const unsigned char* p = *pp;
int x = 0;
for (size_t i = 0; i < n; i++)
x = 10 * x + p[i] - '0';
*pp = p + n;
*np = *np - n;
return x;
}
int64_t ASN1TimeToSec(const unsigned char* s, size_t length, bool long_format) {
size_t bytes_left = length;
// Make sure the string ends with Z. Doing it here protects the strspn call
// from running off the end of the string in Z's absense.
if (length == 0 || s[length - 1] != 'Z')
return -1;
// Make sure we only have ASCII digits so that we don't need to clutter the
// code below and ASN1ReadInt with error checking.
size_t n = strspn(reinterpret_cast<const char*>(s), "0123456789");
if (n + 1 != length)
return -1;
int year;
// Read out ASN1 year, in either 2-char "UTCTIME" or 4-char "GENERALIZEDTIME"
// format. Both format use UTC in this context.
if (long_format) {
// ASN1 format: yyyymmddhh[mm[ss[.fff]]]Z where the Z is literal, but
// RFC 5280 requires us to only support exactly yyyymmddhhmmssZ.
if (bytes_left < 11)
return -1;
year = ASN1ReadInt(&s, &bytes_left, 4);
year -= 1900;
} else {
// ASN1 format: yymmddhhmm[ss]Z where the Z is literal, but RFC 5280
// requires us to only support exactly yymmddhhmmssZ.
if (bytes_left < 9)
return -1;
year = ASN1ReadInt(&s, &bytes_left, 2);
if (year < 50) // Per RFC 5280 4.1.2.5.1
year += 100;
}
std::tm tm;
tm.tm_year = year;
// Read out remaining ASN1 time data and store it in |tm| in documented
// std::tm format.
tm.tm_mon = ASN1ReadInt(&s, &bytes_left, 2) - 1;
tm.tm_mday = ASN1ReadInt(&s, &bytes_left, 2);
tm.tm_hour = ASN1ReadInt(&s, &bytes_left, 2);
tm.tm_min = ASN1ReadInt(&s, &bytes_left, 2);
tm.tm_sec = ASN1ReadInt(&s, &bytes_left, 2);
if (bytes_left != 1) {
// Now just Z should remain. Its existence was asserted above.
return -1;
}
return TmToSeconds(tm);
}
} // namespace rtc