1 /*
2  * libwebsockets - small server side websockets and web server implementation
3  *
4  * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  */
24 
25 enum lws_tls_cert_info {
26 	LWS_TLS_CERT_INFO_VALIDITY_FROM,
27 	/**< fills .time with the time_t the cert validity started from */
28 	LWS_TLS_CERT_INFO_VALIDITY_TO,
29 	/**< fills .time with the time_t the cert validity ends at */
30 	LWS_TLS_CERT_INFO_COMMON_NAME,
31 	/**< fills up to len bytes of .ns.name with the cert common name */
32 	LWS_TLS_CERT_INFO_ISSUER_NAME,
33 	/**< fills up to len bytes of .ns.name with the cert issuer name */
34 	LWS_TLS_CERT_INFO_USAGE,
35 	/**< fills verified with a bitfield asserting the valid uses */
36 	LWS_TLS_CERT_INFO_VERIFIED,
37 	/**< fills .verified with a bool representing peer cert validity,
38 	 *   call returns -1 if no cert */
39 	LWS_TLS_CERT_INFO_OPAQUE_PUBLIC_KEY,
40 	/**< the certificate's public key, as an opaque bytestream.  These
41 	 * opaque bytestreams can only be compared with each other using the
42 	 * same tls backend, ie, OpenSSL or mbedTLS.  The different backends
43 	 * produce different, incompatible representations for the same cert.
44 	 */
45 	LWS_TLS_CERT_INFO_DER_RAW,
46 	/**< the certificate's raw DER representation.  If it's too big,
47 	 * -1 is returned and the size will be returned in buf->ns.len.
48 	 * If the certificate cannot be found -1 is returned and 0 in
49 	 * buf->ns.len. */
50 };
51 
52 union lws_tls_cert_info_results {
53 	unsigned int verified;
54 	time_t time;
55 	unsigned int usage;
56 	struct {
57 		int len;
58 		/* KEEP LAST... notice the [64] is only there because
59 		 * name[] is not allowed in a union.  The actual length of
60 		 * name[] is arbitrary and is passed into the api using the
61 		 * len parameter.  Eg
62 		 *
63 		 * char big[1024];
64 		 * union lws_tls_cert_info_results *buf =
65 		 * 	(union lws_tls_cert_info_results *)big;
66 		 *
67 		 * lws_tls_peer_cert_info(wsi, type, buf, sizeof(big) -
68 		 *			  sizeof(*buf) + sizeof(buf->ns.name));
69 		 */
70 		char name[64];
71 	} ns;
72 };
73 
74 struct lws_x509_cert;
75 struct lws_jwk;
76 
77 /**
78  * lws_x509_create() - Allocate an lws_x509_cert object
79  *
80  * \param x509: pointer to lws_x509_cert pointer to be set to allocated object
81  *
82  * Allocates an lws_x509_cert object and set *x509 to point to it.
83  */
84 LWS_VISIBLE LWS_EXTERN int
85 lws_x509_create(struct lws_x509_cert **x509);
86 
87 /**
88  * lws_x509_parse_from_pem() - Read one or more x509 certs in PEM format from memory
89  *
90  * \param x509: pointer to lws_x509_cert object
91  * \param pem: pointer to PEM format content
92  * \param len: length of PEM format content
93  *
94  * Parses PEM certificates in memory into a native x509 representation for the
95  * TLS library.  If there are multiple PEM certs concatenated, they are all
96  * read into the same object and exist as a "chain".
97  *
98  * IMPORTANT for compatibility with mbedtls, the last used byte of \p pem
99  * must be '\0' and the \p len must include it.
100  *
101  * Returns 0 if all went OK.
102  */
103 LWS_VISIBLE LWS_EXTERN int
104 lws_x509_parse_from_pem(struct lws_x509_cert *x509, const void *pem, size_t len);
105 
106 /**
107  * lws_x509_verify() - Validate signing relationship between one or more certs
108  *		       and a trusted CA cert
109  *
110  * \param x509: pointer to lws_x509_cert object, may contain multiple
111  * \param trusted: a single, trusted cert object that we are checking for
112  * \param common_name: NULL, or required CN (Common Name) of \p x509
113  *
114  * Returns 0 if the cert or certs in \p x509 represent a complete chain that is
115  * ultimately signed by the cert in \p trusted.  Returns nonzero if that's not
116  * the case.
117  */
118 LWS_VISIBLE LWS_EXTERN int
119 lws_x509_verify(struct lws_x509_cert *x509, struct lws_x509_cert *trusted,
120 		const char *common_name);
121 
122 /**
123  * lws_x509_public_to_jwk() - Copy the public key out of a cert and into a JWK
124  *
125  * \param jwk: pointer to the jwk to initialize and set to the public key
126  * \param x509: pointer to lws_x509_cert object that has the public key
127  * \param curves: NULL to disallow EC, else a comma-separated list of valid
128  *		  curves using the JWA naming, eg, "P-256,P-384,P-521".
129  * \param rsabits: minimum number of RSA bits required in the cert if RSA
130  *
131  * Returns 0 if JWK was set to the certificate public key correctly and the
132  * curve / the RSA key size was acceptable.  Automatically produces an RSA or
133  * EC JWK depending on what the cert had.
134  */
135 LWS_VISIBLE LWS_EXTERN int
136 lws_x509_public_to_jwk(struct lws_jwk *jwk, struct lws_x509_cert *x509,
137 		       const char *curves, int rsabits);
138 
139 /**
140  * lws_x509_jwk_privkey_pem() - Copy a private key PEM into a jwk that has the
141  *				public part already
142  *
143  * \param jwk: pointer to the jwk to initialize and set to the public key
144  * \param pem: pointer to PEM private key in memory
145  * \param len: length of PEM private key in memory
146  * \param passphrase: NULL or passphrase needed to decrypt private key
147  *
148  * IMPORTANT for compatibility with mbedtls, the last used byte of \p pem
149  * must be '\0' and the \p len must include it.
150  *
151  * Returns 0 if the private key was successfully added to the JWK, else
152  * nonzero if failed.
153  *
154  * The PEM image in memory is zeroed down on both successful and failed exits.
155  * The caller should take care to zero down passphrase if used.
156  */
157 LWS_VISIBLE LWS_EXTERN int
158 lws_x509_jwk_privkey_pem(struct lws_jwk *jwk, void *pem, size_t len,
159 			 const char *passphrase);
160 
161 /**
162  * lws_x509_destroy() - Destroy a previously allocated lws_x509_cert object
163  *
164  * \param x509: pointer to lws_x509_cert pointer
165  *
166  * Deallocates an lws_x509_cert object and sets its pointer to NULL.
167  */
168 LWS_VISIBLE LWS_EXTERN void
169 lws_x509_destroy(struct lws_x509_cert **x509);
170 
171 LWS_VISIBLE LWS_EXTERN int
172 lws_x509_info(struct lws_x509_cert *x509, enum lws_tls_cert_info type,
173 	      union lws_tls_cert_info_results *buf, size_t len);
174 
175 /**
176  * lws_tls_peer_cert_info() - get information from the peer's TLS cert
177  *
178  * \param wsi: the connection to query
179  * \param type: one of LWS_TLS_CERT_INFO_
180  * \param buf: pointer to union to take result
181  * \param len: when result is a string, the true length of buf->ns.name[]
182  *
183  * lws_tls_peer_cert_info() lets you get hold of information from the peer
184  * certificate.
185  *
186  * Return 0 if there is a result in \p buf, or -1 indicating there was no cert
187  * or another problem.
188  *
189  * This function works the same no matter if the TLS backend is OpenSSL or
190  * mbedTLS.
191  */
192 LWS_VISIBLE LWS_EXTERN int
193 lws_tls_peer_cert_info(struct lws *wsi, enum lws_tls_cert_info type,
194 		       union lws_tls_cert_info_results *buf, size_t len);
195 
196 /**
197  * lws_tls_vhost_cert_info() - get information from the vhost's own TLS cert
198  *
199  * \param vhost: the vhost to query
200  * \param type: one of LWS_TLS_CERT_INFO_
201  * \param buf: pointer to union to take result
202  * \param len: when result is a string, the true length of buf->ns.name[]
203  *
204  * lws_tls_vhost_cert_info() lets you get hold of information from the vhost
205  * certificate.
206  *
207  * Return 0 if there is a result in \p buf, or -1 indicating there was no cert
208  * or another problem.
209  *
210  * This function works the same no matter if the TLS backend is OpenSSL or
211  * mbedTLS.
212  */
213 LWS_VISIBLE LWS_EXTERN int
214 lws_tls_vhost_cert_info(struct lws_vhost *vhost, enum lws_tls_cert_info type,
215 		        union lws_tls_cert_info_results *buf, size_t len);
216 
217 /**
218  * lws_tls_acme_sni_cert_create() - creates a temp selfsigned cert
219  *				    and attaches to a vhost
220  *
221  * \param vhost: the vhost to acquire the selfsigned cert
222  * \param san_a: SAN written into the certificate
223  * \param san_b: second SAN written into the certificate
224  *
225  *
226  * Returns 0 if created and attached to the vhost.  Returns -1 if problems and
227  * frees all allocations before returning.
228  *
229  * On success, any allocations are destroyed at vhost destruction automatically.
230  */
231 LWS_VISIBLE LWS_EXTERN int
232 lws_tls_acme_sni_cert_create(struct lws_vhost *vhost, const char *san_a,
233 			     const char *san_b);
234 
235 /**
236  * lws_tls_acme_sni_csr_create() - creates a CSR and related private key PEM
237  *
238  * \param context: lws_context used for random
239  * \param elements: array of LWS_TLS_REQ_ELEMENT_COUNT const char *
240  * \param csr: buffer that will get the b64URL(ASN-1 CSR)
241  * \param csr_len: max length of the csr buffer
242  * \param privkey_pem: pointer to pointer allocated to hold the privkey_pem
243  * \param privkey_len: pointer to size_t set to the length of the privkey_pem
244  *
245  * Creates a CSR according to the information in \p elements, and a private
246  * RSA key used to sign the CSR.
247  *
248  * The outputs are the b64URL(ASN-1 CSR) into csr, and the PEM private key into
249  * privkey_pem.
250  *
251  * Notice that \p elements points to an array of const char *s pointing to the
252  * information listed in the enum above.  If an entry is NULL or an empty
253  * string, the element is set to "none" in the CSR.
254  *
255  * Returns 0 on success or nonzero for failure.
256  */
257 LWS_VISIBLE LWS_EXTERN int
258 lws_tls_acme_sni_csr_create(struct lws_context *context, const char *elements[],
259 			    uint8_t *csr, size_t csr_len, char **privkey_pem,
260 			    size_t *privkey_len);
261 
262 /**
263  * lws_tls_cert_updated() - update every vhost using the given cert path
264  *
265  * \param context: our lws_context
266  * \param certpath: the filepath to the certificate
267  * \param keypath: the filepath to the private key of the certificate
268  * \param mem_cert: copy of the cert in memory
269  * \param len_mem_cert: length of the copy of the cert in memory
270  * \param mem_privkey: copy of the private key in memory
271  * \param len_mem_privkey: length of the copy of the private key in memory
272  *
273  * Checks every vhost to see if it is the using certificate described by the
274  * the given filepaths.  If so, it attempts to update the vhost ssl_ctx to use
275  * the new certificate.
276  *
277  * Returns 0 on success or nonzero for failure.
278  */
279 LWS_VISIBLE LWS_EXTERN int
280 lws_tls_cert_updated(struct lws_context *context, const char *certpath,
281 		     const char *keypath,
282 		     const char *mem_cert, size_t len_mem_cert,
283 		     const char *mem_privkey, size_t len_mem_privkey);
284 
285