aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/objective-c/GRPCClient/private/GRPCHost.m
blob: 1159aac7a71268896fd51cddcee833010ea4ea6a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#import "GRPCHost.h"

#include <grpc/grpc.h>
#include <grpc/grpc_security.h>
#import <GRPCClient/GRPCCall.h>
#ifdef GRPC_COMPILE_WITH_CRONET
#import <GRPCClient/GRPCCall+ChannelArg.h>
#import <GRPCClient/GRPCCall+Cronet.h>
#endif

#import "GRPCChannel.h"
#import "GRPCCompletionQueue.h"
#import "NSDictionary+GRPC.h"

NS_ASSUME_NONNULL_BEGIN

// TODO(jcanizales): Generate the version in a standalone header, from templates. Like
// templates/src/core/surface/version.c.template .
#define GRPC_OBJC_VERSION_STRING @"1.0.0"

static NSMutableDictionary *kHostCache;

@implementation GRPCHost {
  // TODO(mlumish): Investigate whether caching channels with strong links is a good idea.
  GRPCChannel *_channel;
}

+ (nullable instancetype)hostWithAddress:(NSString *)address {
  return [[self alloc] initWithAddress:address];
}

- (void)dealloc {
  if (_channelCreds != nil) {
    grpc_channel_credentials_release(_channelCreds);
  }
}

// Default initializer.
- (nullable instancetype)initWithAddress:(NSString *)address {
  if (!address) {
    return nil;
  }

  // To provide a default port, we try to interpret the address. If it's just a host name without
  // scheme and without port, we'll use port 443. If it has a scheme, we pass it untouched to the C
  // gRPC library.
  // TODO(jcanizales): Add unit tests for the types of addresses we want to let pass untouched.
  NSURL *hostURL = [NSURL URLWithString:[@"https://" stringByAppendingString:address]];
  if (hostURL.host && !hostURL.port) {
    address = [hostURL.host stringByAppendingString:@":443"];
  }

  // Look up the GRPCHost in the cache.
  static dispatch_once_t cacheInitialization;
  dispatch_once(&cacheInitialization, ^{
    kHostCache = [NSMutableDictionary dictionary];
  });
  @synchronized(kHostCache) {
    GRPCHost *cachedHost = kHostCache[address];
    if (cachedHost) {
      return cachedHost;
    }

    if ((self = [super init])) {
      _address = address;
      _secure = YES;
      kHostCache[address] = self;
    }
  }
  return self;
}

+ (void)flushChannelCache {
  @synchronized(kHostCache) {
    [kHostCache enumerateKeysAndObjectsUsingBlock:^(id  _Nonnull key,
                                                    GRPCHost * _Nonnull host,
                                                    BOOL * _Nonnull stop) {
      [host disconnect];
    }];
  }
}

+ (void)resetAllHostSettings {
  @synchronized (kHostCache) {
    kHostCache = [NSMutableDictionary dictionary];
  }
}

- (nullable grpc_call *)unmanagedCallWithPath:(NSString *)path
                              completionQueue:(GRPCCompletionQueue *)queue {
  GRPCChannel *channel;
  // This is racing -[GRPCHost disconnect].
  @synchronized(self) {
    if (!_channel) {
      _channel = [self newChannel];
    }
    channel = _channel;
  }
  return [channel unmanagedCallWithPath:path completionQueue:queue];
}

- (BOOL)setTLSPEMRootCerts:(nullable NSString *)pemRootCerts
            withPrivateKey:(nullable NSString *)pemPrivateKey
             withCertChain:(nullable NSString *)pemCertChain
                     error:(NSError **)errorPtr {
  static NSData *kDefaultRootsASCII;
  static NSError *kDefaultRootsError;
  static dispatch_once_t loading;
  dispatch_once(&loading, ^{
    NSString *defaultPath = @"gRPCCertificates.bundle/roots"; // .pem
    // Do not use NSBundle.mainBundle, as it's nil for tests of library projects.
    NSBundle *bundle = [NSBundle bundleForClass:self.class];
    NSString *path = [bundle pathForResource:defaultPath ofType:@"pem"];
    NSError *error;
    // Files in PEM format can have non-ASCII characters in their comments (e.g. for the name of the
    // issuer). Load them as UTF8 and produce an ASCII equivalent.
    NSString *contentInUTF8 = [NSString stringWithContentsOfFile:path
                                                        encoding:NSUTF8StringEncoding
                                                           error:&error];
    if (contentInUTF8 == nil) {
      kDefaultRootsError = error;
      return;
    }
    kDefaultRootsASCII = [contentInUTF8 dataUsingEncoding:NSASCIIStringEncoding
                                     allowLossyConversion:YES];
  });

  NSData *rootsASCII;
  if (pemRootCerts != nil) {
    rootsASCII = [pemRootCerts dataUsingEncoding:NSASCIIStringEncoding
                     allowLossyConversion:YES];
  } else {
    if (kDefaultRootsASCII == nil) {
      if (errorPtr) {
        *errorPtr = kDefaultRootsError;
      }
      NSAssert(kDefaultRootsASCII, @"Could not read gRPCCertificates.bundle/roots.pem. This file, "
               "with the root certificates, is needed to establish secure (TLS) connections. "
               "Because the file is distributed with the gRPC library, this error is usually a sign "
               "that the library wasn't configured correctly for your project. Error: %@",
                kDefaultRootsError);
      return NO;
    }
    rootsASCII = kDefaultRootsASCII;
  }

  grpc_channel_credentials *creds;
  if (pemPrivateKey == nil && pemCertChain == nil) {
    creds = grpc_ssl_credentials_create(rootsASCII.bytes, NULL, NULL);
  } else {
    grpc_ssl_pem_key_cert_pair key_cert_pair;
    NSData *privateKeyASCII = [pemPrivateKey dataUsingEncoding:NSASCIIStringEncoding
                                       allowLossyConversion:YES];
    NSData *certChainASCII = [pemCertChain dataUsingEncoding:NSASCIIStringEncoding
                                     allowLossyConversion:YES];
    key_cert_pair.private_key = privateKeyASCII.bytes;
    key_cert_pair.cert_chain = certChainASCII.bytes;
    creds = grpc_ssl_credentials_create(rootsASCII.bytes, &key_cert_pair, NULL);
  }

  @synchronized(self) {
    if (_channelCreds != nil) {
      grpc_channel_credentials_release(_channelCreds);
    }
    _channelCreds = creds;
  }

  return YES;
}

- (NSDictionary *)channelArgs {
  NSMutableDictionary *args = [NSMutableDictionary dictionary];

  // TODO(jcanizales): Add OS and device information (see
  // https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#user-agents ).
  NSString *userAgent = @"grpc-objc/" GRPC_OBJC_VERSION_STRING;
  if (_userAgentPrefix) {
    userAgent = [_userAgentPrefix stringByAppendingFormat:@" %@", userAgent];
  }
  args[@GRPC_ARG_PRIMARY_USER_AGENT_STRING] = userAgent;

  if (_secure && _hostNameOverride) {
    args[@GRPC_SSL_TARGET_NAME_OVERRIDE_ARG] = _hostNameOverride;
  }

  if (_responseSizeLimitOverride) {
    args[@GRPC_ARG_MAX_RECEIVE_MESSAGE_LENGTH] = _responseSizeLimitOverride;
  }
  return args;
}

- (GRPCChannel *)newChannel {
  NSDictionary *args = [self channelArgs];
#ifdef GRPC_COMPILE_WITH_CRONET
  BOOL useCronet = [GRPCCall isUsingCronet];
#endif
  if (_secure) {
      GRPCChannel *channel;
      @synchronized(self) {
        if (_channelCreds == nil) {
          [self setTLSPEMRootCerts:nil withPrivateKey:nil withCertChain:nil error:nil];
        }
#ifdef GRPC_COMPILE_WITH_CRONET
        if (useCronet) {
          channel = [GRPCChannel secureCronetChannelWithHost:_address
                                                 channelArgs:args];
        } else
#endif
        {
          channel = [GRPCChannel secureChannelWithHost:_address
                                            credentials:_channelCreds
                                            channelArgs:args];
        }
      }
      return channel;
  } else {
    return [GRPCChannel insecureChannelWithHost:_address channelArgs:args];
  }
}

- (NSString *)hostName {
  // TODO(jcanizales): Default to nil instead of _address when Issue #2635 is clarified.
  return _hostNameOverride ?: _address;
}

- (void)disconnect {
  // This is racing -[GRPCHost unmanagedCallWithPath:completionQueue:].
  @synchronized(self) {
    _channel = nil;
  }
}

@end

NS_ASSUME_NONNULL_END