xref: /openbmc/openpower-pnor-code-mgmt/image_verify.hpp (revision bbb5e3bec1ca0cc073e9096ced453adc23fecffb)
1 #pragma once
2 #include "utils.hpp"
3 
4 #include <openssl/evp.h>
5 #include <openssl/pem.h>
6 #include <openssl/rsa.h>
7 #include <sys/mman.h>
8 #include <unistd.h>
9 
10 #include <experimental/filesystem>
11 #include <set>
12 #include <string>
13 
14 namespace openpower
15 {
16 namespace software
17 {
18 namespace image
19 {
20 
21 namespace fs = std::experimental::filesystem;
22 using Key_t = std::string;
23 using Hash_t = std::string;
24 using PublicKeyPath = fs::path;
25 using HashFilePath = fs::path;
26 using KeyHashPathPair = std::pair<HashFilePath, PublicKeyPath>;
27 using AvailableKeyTypes = std::set<Key_t>;
28 
29 // RAII support for openSSL functions.
30 using BIO_MEM_Ptr = std::unique_ptr<BIO, decltype(&::BIO_free)>;
31 using EVP_PKEY_Ptr = std::unique_ptr<EVP_PKEY, decltype(&::EVP_PKEY_free)>;
32 using EVP_MD_CTX_Ptr =
33     std::unique_ptr<EVP_MD_CTX, decltype(&::EVP_MD_CTX_free)>;
34 
35 /** @struct CustomFd
36  *
37  *  RAII wrapper for file descriptor.
38  */
39 struct CustomFd
40 {
41   public:
42     CustomFd() = delete;
43     CustomFd(const CustomFd&) = delete;
44     CustomFd& operator=(const CustomFd&) = delete;
45     CustomFd(CustomFd&&) = default;
46     CustomFd& operator=(CustomFd&&) = default;
47     /** @brief Saves File descriptor and uses it to do file operation
48      *
49      *  @param[in] fd - File descriptor
50      */
51     explicit CustomFd(int fd) : fd(fd)
52     {
53     }
54 
55     ~CustomFd()
56     {
57         if (fd >= 0)
58         {
59             close(fd);
60         }
61     }
62 
63     int operator()() const
64     {
65         return fd;
66     }
67 
68   private:
69     /** @brief File descriptor */
70     int fd = -1;
71 };
72 
73 /** @struct CustomMap
74  *
75  *  RAII wrapper for mmap.
76  */
77 struct CustomMap
78 {
79   private:
80     /** @brief starting address of the map   */
81     void* addr;
82 
83     /** @brief length of the mapping   */
84     size_t length;
85 
86   public:
87     CustomMap() = delete;
88     CustomMap(const CustomMap&) = delete;
89     CustomMap& operator=(const CustomMap&) = delete;
90     CustomMap(CustomMap&&) = default;
91     CustomMap& operator=(CustomMap&&) = default;
92 
93     /** @brief Saves starting address of the map and
94      *         and length of the file.
95      *  @param[in]  addr - Starting address of the map
96      *  @param[in]  length - length of the map
97      */
98     CustomMap(void* addr, size_t length) : addr(addr), length(length)
99     {
100     }
101 
102     ~CustomMap()
103     {
104         munmap(addr, length);
105     }
106 
107     void* operator()() const
108     {
109         return addr;
110     }
111 };
112 
113 /** @class Signature
114  *  @brief Contains signature verification functions.
115  *  @details The software image class that contains the signature
116  *           verification functions for signed image.
117  */
118 class Signature
119 {
120   public:
121     Signature() = delete;
122     Signature(const Signature&) = delete;
123     Signature& operator=(const Signature&) = delete;
124     Signature(Signature&&) = default;
125     Signature& operator=(Signature&&) = default;
126     ~Signature() = default;
127 
128     /**
129      * @brief Constructs Signature.
130      * @param[in]  imageDirPath - image path
131      * @param[in]  signedConfPath - Path of public key
132      *                              hash function files
133      */
134     explicit Signature(const fs::path& imageDirPath,
135                        const std::string& pnorFileName,
136                        const fs::path& signedConfPath);
137 
138     /**
139      * @brief Image signature verification function.
140      *        Verify the Manifest and public key file signature using the
141      *        public keys available in the system first. After successful
142      *        validation, continue the whole image files signature
143      *        validation using the image specific public key and the
144      *        hash function.
145      *
146      *        @return true if signature verification was successful,
147      *                     false if not
148      */
149     bool verify();
150 
151   private:
152     /**
153      * @brief Function used for system level file signature validation
154      *        of image specific publickey file and manifest file
155      *        using the available public keys and hash functions
156      *        in the system.
157      *        Refer code-update documentation for more details.
158      */
159     bool systemLevelVerify();
160 
161     /**
162      *  @brief Return all key types stored in the BMC based on the
163      *         public key and hashfunc files stored in the BMC.
164      *
165      *  @return list
166      */
167     AvailableKeyTypes getAvailableKeyTypesFromSystem() const;
168 
169     /**
170      *  @brief Return public key and hash function file names for the
171      *  corresponding key type
172      *
173      *  @param[in]  key - key type
174      *  @return Pair of hash and public key file names
175      */
176     inline KeyHashPathPair getKeyHashFileNames(const Key_t& key) const;
177 
178     /**
179      * @brief Verify the file signature using public key and hash function
180      *
181      * @param[in]  - Image file path
182      * @param[in]  - Signature file path
183      * @param[in]  - Public key
184      * @param[in]  - Hash function name
185      * @return true if signature verification was successful, false if not
186      */
187     bool verifyFile(const fs::path& file, const fs::path& signature,
188                     const fs::path& publicKey, const std::string& hashFunc);
189 
190     /**
191      * @brief Create RSA object from the public key
192      * @param[in]  - publickey
193      * @param[out] - RSA Object.
194      */
195     inline RSA* createPublicRSA(const fs::path& publicKey);
196 
197     /**
198      * @brief Memory map the  file
199      * @param[in]  - file path
200      * @param[in]  - file size
201      * @param[out] - Custom Mmap address
202      */
203     CustomMap mapFile(const fs::path& path, size_t size);
204 
205     /** @brief Directory where software images are placed*/
206     fs::path imageDirPath;
207 
208     /** @brief The PNOR file name in imageDirPath */
209     std::string pnorFileName;
210 
211     /** @brief Path of public key and hash function files */
212     fs::path signedConfPath;
213 
214     /** @brief key type defined in mainfest file */
215     Key_t keyType;
216 
217     /** @brief Hash type defined in mainfest file */
218     Hash_t hashType;
219 };
220 
221 } // namespace image
222 } // namespace software
223 } // namespace openpower
224