summaryrefslogtreecommitdiff
path: root/src/libcamera/ipa_manager.cpp
blob: 93d02d947c468fcc321ec4f9c2da1b6545ad2946 (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
269
270
271
272
273
274
275
276
277
278
279
280
281
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * ipa_manager.cpp - Image Processing Algorithm module manager
 */

#include "libcamera/internal/ipa_manager.h"

#include <algorithm>
#include <dirent.h>
#include <string.h>
#include <sys/types.h>

#include "libcamera/internal/file.h"
#include "libcamera/internal/ipa_module.h"
#include "libcamera/internal/ipa_proxy.h"
#include "libcamera/internal/log.h"
#include "libcamera/internal/pipeline_handler.h"
#include "libcamera/internal/utils.h"

/**
 * \file ipa_manager.h
 * \brief Image Processing Algorithm module manager
 */

namespace libcamera {

LOG_DEFINE_CATEGORY(IPAManager)

/**
 * \class IPAManager
 * \brief Manager for IPA modules
 *
 * The IPA module manager discovers IPA modules from disk, queries and loads
 * them, and creates IPA contexts. It supports isolation of the modules in a
 * separate process with IPC communication and offers a unified IPAInterface
 * view of the IPA contexts to pipeline handlers regardless of whether the
 * modules are isolated or loaded in the same process.
 *
 * Module isolation is based on the module licence. Open-source modules are
 * loaded without isolation, while closed-source module are forcefully isolated.
 * The isolation mechanism ensures that no code from a closed-source module is
 * ever run in the libcamera process.
 *
 * To create an IPA context, pipeline handlers call the IPAManager::createIPA()
 * method. For a directly loaded module, the manager calls the module's
 * ipaCreate() function directly and wraps the returned context in an
 * IPAContextWrapper that exposes an IPAInterface.
 *
 * ~~~~
 * +---------------+
 * |   Pipeline    |
 * |    Handler    |
 * +---------------+
 *         |
 *         v
 * +---------------+                   +---------------+
 * |      IPA      |                   |  Open Source  |
 * |   Interface   |                   |  IPA Module   |
 * | - - - - - - - |                   | - - - - - - - |
 * |  IPA Context  |  ipa_context_ops  |  ipa_context  |
 * |    Wrapper    | ----------------> |               |
 * +---------------+                   +---------------+
 * ~~~~
 *
 * For an isolated module, the manager instantiates an IPAProxy which spawns a
 * new process for an IPA proxy worker. The worker loads the IPA module and
 * creates the IPA context. The IPAProxy alse exposes an IPAInterface.
 *
 * ~~~~
 * +---------------+                   +---------------+
 * |   Pipeline    |                   | Closed Source |
 * |    Handler    |                   |  IPA Module   |
 * +---------------+                   | - - - - - - - |
 *         |                           |  ipa_context  |
 *         v                           |               |
 * +---------------+                   +---------------+
 * |      IPA      |           ipa_context_ops ^
 * |   Interface   |                           |
 * | - - - - - - - |                   +---------------+
 * |   IPA Proxy   |     operations    |   IPA Proxy   |
 * |               | ----------------> |    Worker     |
 * +---------------+      over IPC     +---------------+
 * ~~~~
 *
 * The IPAInterface implemented by the IPAContextWrapper or IPAProxy is
 * returned to the pipeline handler, and all interactions with the IPA context
 * go the same interface regardless of process isolation.
 *
 * In all cases the data passed to the IPAInterface methods is serialized to
 * Plain Old Data, either for the purpose of passing it to the IPA context
 * plain C API, or to transmit the data to the isolated process through IPC.
 */

IPAManager *IPAManager::self_ = nullptr;

/**
 * \brief Construct an IPAManager instance
 *
 * The IPAManager class is meant to only be instantiated once, by the
 * CameraManager.
 */
IPAManager::IPAManager()
{
	if (self_)
		LOG(IPAManager, Fatal)
			<< "Multiple IPAManager objects are not allowed";

	unsigned int ipaCount = 0;

	/* User-specified paths take precedence. */
	const char *modulePaths = utils::secure_getenv("LIBCAMERA_IPA_MODULE_PATH");
	if (modulePaths) {
		for (const auto &dir : utils::split(modulePaths, ":")) {
			if (dir.empty())
				continue;

			ipaCount += addDir(dir.c_str());
		}

		if (!ipaCount)
			LOG(IPAManager, Warning)
				<< "No IPA found in '" << modulePaths << "'";
	}

	/*
	 * When libcamera is used before it is installed, load IPAs from the
	 * same build directory as the libcamera library itself.
	 */
	std::string root = utils::libcameraBuildPath();
	if (!root.empty()) {
		std::string ipaBuildPath = root + "src/ipa";
		constexpr int maxDepth = 1;

		LOG(IPAManager, Info)
			<< "libcamera is not installed. Adding '"
			<< ipaBuildPath << "' to the IPA search path";

		ipaCount += addDir(ipaBuildPath.c_str(), maxDepth);
	}

	/* Finally try to load IPAs from the installed system path. */
	ipaCount += addDir(IPA_MODULE_DIR);

	if (!ipaCount)
		LOG(IPAManager, Warning)
			<< "No IPA found in '" IPA_MODULE_DIR "'";

	self_ = this;
}

IPAManager::~IPAManager()
{
	for (IPAModule *module : modules_)
		delete module;

	self_ = nullptr;
}

/**
 * \brief Identify shared library objects within a directory
 * \param[in] libDir The directory to search for shared objects
 * \param[in] maxDepth The maximum depth of sub-directories to parse
 * \param[out] files A vector of paths to shared object library files
 *
 * Search a directory for .so files, allowing recursion down to sub-directories
 * no further than the depth specified by \a maxDepth.
 *
 * Discovered shared objects are added to the \a files vector.
 */
void IPAManager::parseDir(const char *libDir, unsigned int maxDepth,
			  std::vector<std::string> &files)
{
	struct dirent *ent;
	DIR *dir;

	dir = opendir(libDir);
	if (!dir)
		return;

	while ((ent = readdir(dir)) != nullptr) {
		if (ent->d_type == DT_DIR && maxDepth) {
			if (strcmp(ent->d_name, ".") == 0 ||
			    strcmp(ent->d_name, "..") == 0)
				continue;

			std::string subdir = std::string(libDir) + "/" + ent->d_name;

			/* Recursion is limited to maxDepth. */
			parseDir(subdir.c_str(), maxDepth - 1, files);

			continue;
		}

		int offset = strlen(ent->d_name) - 3;
		if (offset < 0)
			continue;
		if (strcmp(&ent->d_name[offset], ".so"))
			continue;

		files.push_back(std::string(libDir) + "/" + ent->d_name);
	}

	closedir(dir);
}

/**
 * \brief Load IPA modules from a directory
 * \param[in] libDir The directory to search for IPA modules
 * \param[in] maxDepth The maximum depth of sub-directories to search
 *
 * This method tries to create an IPAModule instance for every shared object
 * found in \a libDir, and skips invalid IPA modules.
 *
 * Sub-directories are searched up to a depth of \a maxDepth. A \a maxDepth
 * value of 0 only searches the directory specified in \a libDir.
 *
 * \return Number of modules loaded by this call
 */
unsigned int IPAManager::addDir(const char *libDir, unsigned int maxDepth)
{
	std::vector<std::string> files;

	parseDir(libDir, maxDepth, files);

	/* Ensure a stable ordering of modules. */
	std::sort(files.begin(), files.end());

	unsigned int count = 0;
	for (const std::string &file : files) {
		IPAModule *ipaModule = new IPAModule(file);
		if (!ipaModule->isValid()) {
			delete ipaModule;
			continue;
		}

		LOG(IPAManager, Debug) << "Loaded IPA module '" << file << "'";

		modules_.push_back(ipaModule);
		count++;
	}

	return count;
}

/**
 * \fn IPAManager::createIPA()
 * \brief Create an IPA proxy that matches a given pipeline handler
 * \param[in] pipe The pipeline handler that wants a matching IPA proxy
 * \param[in] minVersion Minimum acceptable version of IPA module
 * \param[in] maxVersion Maximum acceptable version of IPA module
 *
 * \return A newly created IPA proxy, or nullptr if no matching IPA module is
 * found or if the IPA proxy fails to initialize
 */

bool IPAManager::isSignatureValid([[maybe_unused]] IPAModule *ipa) const
{
#if HAVE_IPA_PUBKEY
	File file{ ipa->path() };
	if (!file.open(File::ReadOnly))
		return false;

	Span<uint8_t> data = file.map();
	if (data.empty())
		return false;

	bool valid = pubKey_.verify(data, ipa->signature());

	LOG(IPAManager, Debug)
		<< "IPA module " << ipa->path() << " signature is "
		<< (valid ? "valid" : "not valid");

	return valid;
#else
	return false;
#endif
}

} /* namespace libcamera */