1 // Copyright 2015 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "net/ssl/ssl_platform_key_nss.h"
6
7 #include <cert.h>
8 #include <keyhi.h>
9 #include <pk11pub.h>
10 #include <prerror.h>
11 #include <secmodt.h>
12
13 #include <memory>
14 #include <utility>
15
16 #include "base/logging.h"
17 #include "base/strings/stringprintf.h"
18 #include "base/threading/scoped_blocking_call.h"
19 #include "crypto/nss_crypto_module_delegate.h"
20 #include "crypto/scoped_nss_types.h"
21 #include "net/cert/x509_certificate.h"
22 #include "net/ssl/ssl_platform_key_util.h"
23 #include "net/ssl/ssl_private_key.h"
24 #include "net/ssl/threaded_ssl_private_key.h"
25 #include "third_party/boringssl/src/include/openssl/bn.h"
26 #include "third_party/boringssl/src/include/openssl/bytestring.h"
27 #include "third_party/boringssl/src/include/openssl/ec.h"
28 #include "third_party/boringssl/src/include/openssl/ec_key.h"
29 #include "third_party/boringssl/src/include/openssl/ecdsa.h"
30 #include "third_party/boringssl/src/include/openssl/evp.h"
31 #include "third_party/boringssl/src/include/openssl/mem.h"
32 #include "third_party/boringssl/src/include/openssl/nid.h"
33 #include "third_party/boringssl/src/include/openssl/rsa.h"
34 #include "third_party/boringssl/src/include/openssl/ssl.h"
35
36 namespace net {
37
38 namespace {
39
LogPRError(const char * message)40 void LogPRError(const char* message) {
41 PRErrorCode err = PR_GetError();
42 const char* err_name = PR_ErrorToName(err);
43 if (err_name == nullptr)
44 err_name = "";
45 LOG(ERROR) << message << ": " << err << " (" << err_name << ")";
46 }
47
48 class SSLPlatformKeyNSS : public ThreadedSSLPrivateKey::Delegate {
49 public:
SSLPlatformKeyNSS(int type,scoped_refptr<crypto::CryptoModuleBlockingPasswordDelegate> password_delegate,crypto::ScopedSECKEYPrivateKey key)50 SSLPlatformKeyNSS(int type,
51 scoped_refptr<crypto::CryptoModuleBlockingPasswordDelegate>
52 password_delegate,
53 crypto::ScopedSECKEYPrivateKey key)
54 : type_(type),
55 password_delegate_(std::move(password_delegate)),
56 key_(std::move(key)),
57 supports_pss_(PK11_DoesMechanism(key_->pkcs11Slot, CKM_RSA_PKCS_PSS)) {}
58
59 SSLPlatformKeyNSS(const SSLPlatformKeyNSS&) = delete;
60 SSLPlatformKeyNSS& operator=(const SSLPlatformKeyNSS&) = delete;
61
62 ~SSLPlatformKeyNSS() override = default;
63
GetProviderName()64 std::string GetProviderName() override {
65 // This logic accesses fields directly on the struct, so it may run on any
66 // thread without caching.
67 return base::StringPrintf("%s, %s",
68 PK11_GetModule(key_->pkcs11Slot)->commonName,
69 PK11_GetSlotName(key_->pkcs11Slot));
70 }
71
GetAlgorithmPreferences()72 std::vector<uint16_t> GetAlgorithmPreferences() override {
73 return SSLPrivateKey::DefaultAlgorithmPreferences(type_, supports_pss_);
74 }
75
Sign(uint16_t algorithm,base::span<const uint8_t> input,std::vector<uint8_t> * signature)76 Error Sign(uint16_t algorithm,
77 base::span<const uint8_t> input,
78 std::vector<uint8_t>* signature) override {
79 const EVP_MD* md = SSL_get_signature_algorithm_digest(algorithm);
80 uint8_t digest[EVP_MAX_MD_SIZE];
81 unsigned digest_len;
82 if (!md || !EVP_Digest(input.data(), input.size(), digest, &digest_len, md,
83 nullptr)) {
84 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
85 }
86 SECItem digest_item;
87 digest_item.data = digest;
88 digest_item.len = digest_len;
89
90 CK_MECHANISM_TYPE mechanism = PK11_MapSignKeyType(key_->keyType);
91 SECItem param = {siBuffer, nullptr, 0};
92 CK_RSA_PKCS_PSS_PARAMS pss_params;
93 bssl::UniquePtr<uint8_t> free_digest_info;
94 if (SSL_is_signature_algorithm_rsa_pss(algorithm)) {
95 switch (EVP_MD_type(md)) {
96 case NID_sha256:
97 pss_params.hashAlg = CKM_SHA256;
98 pss_params.mgf = CKG_MGF1_SHA256;
99 break;
100 case NID_sha384:
101 pss_params.hashAlg = CKM_SHA384;
102 pss_params.mgf = CKG_MGF1_SHA384;
103 break;
104 case NID_sha512:
105 pss_params.hashAlg = CKM_SHA512;
106 pss_params.mgf = CKG_MGF1_SHA512;
107 break;
108 default:
109 LOG(ERROR) << "Unexpected hash algorithm";
110 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
111 }
112 // Use the hash length for the salt length.
113 pss_params.sLen = EVP_MD_size(md);
114 mechanism = CKM_RSA_PKCS_PSS;
115 param.data = reinterpret_cast<unsigned char*>(&pss_params);
116 param.len = sizeof(pss_params);
117 } else if (SSL_get_signature_algorithm_key_type(algorithm) ==
118 EVP_PKEY_RSA) {
119 // PK11_SignWithMechanism expects the caller to prepend the DigestInfo for
120 // PKCS #1.
121 int hash_nid = EVP_MD_type(SSL_get_signature_algorithm_digest(algorithm));
122 int is_alloced;
123 size_t prefix_len;
124 if (!RSA_add_pkcs1_prefix(&digest_item.data, &prefix_len, &is_alloced,
125 hash_nid, digest_item.data, digest_item.len)) {
126 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
127 }
128 digest_item.len = prefix_len;
129 if (is_alloced)
130 free_digest_info.reset(digest_item.data);
131 }
132
133 {
134 const int len = PK11_SignatureLen(key_.get());
135 if (len <= 0) {
136 LogPRError("PK11_SignatureLen failed");
137 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
138 }
139 signature->resize(len);
140 SECItem signature_item;
141 signature_item.data = signature->data();
142 signature_item.len = signature->size();
143
144 SECStatus rv = PK11_SignWithMechanism(key_.get(), mechanism, ¶m,
145 &signature_item, &digest_item);
146 if (rv != SECSuccess) {
147 LogPRError("PK11_SignWithMechanism failed");
148 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
149 }
150 signature->resize(signature_item.len);
151 }
152
153 // NSS emits raw ECDSA signatures, but BoringSSL expects a DER-encoded
154 // ECDSA-Sig-Value.
155 if (SSL_get_signature_algorithm_key_type(algorithm) == EVP_PKEY_EC) {
156 if (signature->size() % 2 != 0) {
157 LOG(ERROR) << "Bad signature length";
158 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
159 }
160 size_t order_len = signature->size() / 2;
161
162 // Convert the RAW ECDSA signature to a DER-encoded ECDSA-Sig-Value.
163 bssl::UniquePtr<ECDSA_SIG> sig(ECDSA_SIG_new());
164 if (!sig || !BN_bin2bn(signature->data(), order_len, sig->r) ||
165 !BN_bin2bn(signature->data() + order_len, order_len, sig->s)) {
166 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
167 }
168
169 {
170 const int len = i2d_ECDSA_SIG(sig.get(), nullptr);
171 if (len <= 0)
172 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
173 signature->resize(len);
174 }
175
176 {
177 uint8_t* ptr = signature->data();
178 const int len = i2d_ECDSA_SIG(sig.get(), &ptr);
179 if (len <= 0)
180 return ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED;
181 signature->resize(len);
182 }
183 }
184
185 return OK;
186 }
187
188 private:
189 int type_;
190 // NSS retains a pointer to the password delegate, so retain a reference here
191 // to ensure the lifetimes are correct.
192 scoped_refptr<crypto::CryptoModuleBlockingPasswordDelegate>
193 password_delegate_;
194 crypto::ScopedSECKEYPrivateKey key_;
195 bool supports_pss_;
196 };
197
198 } // namespace
199
FetchClientCertPrivateKey(const X509Certificate * certificate,CERTCertificate * cert_certificate,scoped_refptr<crypto::CryptoModuleBlockingPasswordDelegate> password_delegate)200 scoped_refptr<SSLPrivateKey> FetchClientCertPrivateKey(
201 const X509Certificate* certificate,
202 CERTCertificate* cert_certificate,
203 scoped_refptr<crypto::CryptoModuleBlockingPasswordDelegate>
204 password_delegate) {
205 // This function may acquire the NSS lock or reenter this code via extension
206 // hooks (such as smart card UI). To ensure threads are not starved or
207 // deadlocked, the base::ScopedBlockingCall below increments the thread pool
208 // capacity if this method takes too much time to run.
209 base::ScopedBlockingCall scoped_blocking_call(FROM_HERE,
210 base::BlockingType::MAY_BLOCK);
211
212 void* wincx = password_delegate ? password_delegate->wincx() : nullptr;
213 crypto::ScopedSECKEYPrivateKey key(
214 PK11_FindKeyByAnyCert(cert_certificate, wincx));
215 if (!key)
216 return nullptr;
217
218 int type;
219 size_t max_length;
220 if (!GetClientCertInfo(certificate, &type, &max_length))
221 return nullptr;
222
223 // Note that key contains a reference to password_delegate->wincx() and may
224 // use it in PK11_Sign. Thus password_delegate must outlive key. We pass it
225 // into SSLPlatformKeyNSS to tie the lifetimes together. See
226 // https://crbug.com/779090.
227 return base::MakeRefCounted<ThreadedSSLPrivateKey>(
228 std::make_unique<SSLPlatformKeyNSS>(type, std::move(password_delegate),
229 std::move(key)),
230 GetSSLPlatformKeyTaskRunner());
231 }
232
233 } // namespace net
234