forked from mozilla/mwos-letsencrypt-2015
-
Notifications
You must be signed in to change notification settings - Fork 0
/
ngx_http_acme_module.c
1101 lines (891 loc) · 35.8 KB
/
ngx_http_acme_module.c
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
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/**
* @file ngx_http_acme_module.c
* @author Klaus Krapfenbauer <[email protected]>
* @date Fri Oct 30 14:57:23 UTC 2015
*
* @brief An ACME module for Nginx.
*
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
#include <inttypes.h>
#include <string.h>
#include <curl/curl.h>
#include <jansson.h>
#include "ngx_http_acme_lib.h"
#include "ngx_http_acme_module.h"
/*
* String constants
*/
#define ACME_REPLAY_NONCE_PREFIX_STRING ACME_REPLAY_NONCE_HEADER ": "
#define ACME_TOS_PREFIX_STRING "Link: <"
#define ACME_TOS_SUFFIX_STRING ">;rel=\"" ACME_TERMS_LINK_HEADER "\""
#define ACME_LOCATION_HEADER_PREFIX_STRING "Location: "
/*
* Temporary dev macros
*/
/* Nginx config directory; This should later be gathered from nginx */
#define ACME_DEV_CONF_DIR "conf"
/* This should later be replaced with the value of the server_name directive of the core module */
#define ACME_DEV_SERVER_NAME "ledev2.kbauer.at"
#define ACME_DEV_CERT_PATH ACME_DEV_CONF_DIR "/" ACME_DIR "/" ACME_LIVE_DIR "/" ACME_DEV_SERVER_NAME "/" ACME_CERT
#define ACME_DEV_KEY_PATH ACME_DEV_CONF_DIR "/" ACME_DIR "/" ACME_LIVE_DIR "/" ACME_DEV_SERVER_NAME "/" ACME_CERT_KEY
#define ACME_DEV_EXAMPLE_DIR "../example"
#define ACME_DEV_FROM_CERT_PATH ACME_DEV_EXAMPLE_DIR "/cert.pem"
#define ACME_DEV_FROM_KEY_PATH ACME_DEV_EXAMPLE_DIR "/cert-key.pem"
/*
* Function macros
*/
#define println_debug2(str, ngx_str, stream) \
fwrite("ACME DEBUG: ", sizeof(char), strlen("ACME DEBUG: "), stream); \
fwrite(str, sizeof(char), strlen(str), stream); \
fwrite((ngx_str)->data, sizeof(char), (ngx_str)->len, stream); \
fwrite("\n", sizeof(char), 1, stream); \
fflush(stream)
#define println_debug(str, ngx_str) \
println_debug2(str, ngx_str, stdout)
static char *ngx_http_acme(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
static char *ngx_http_acme_main(ngx_conf_t *cf, void *conf);
static char *ngx_http_acme_fetch_dir(ngx_conf_t *cf, void *conf, ngx_str_t *replay_nonce);
static char *ngx_http_acme_new_reg(ngx_conf_t *cf, void *conf, ngx_str_t *replay_nonce, RSA *key);
static char *ngx_http_acme_new_auth(ngx_conf_t *cf, void *conf, ngx_str_t *replay_nonce, RSA *key);
static char *ngx_http_acme_request(ngx_conf_t *cf, void *conf, char *url, ngx_http_acme_http_method_t http_method,
json_t *request_json, RSA *key, ngx_str_t *replay_nonce, json_t **response_json,
ngx_http_acme_slist_t **response_headers);
static char *ngx_http_acme_sign_json(ngx_conf_t *cf, void *conf, json_t *payload, RSA *key, ngx_str_t replay_nonce, json_t **flattened_jws);
static char *ngx_http_acme_create_jwk(ngx_conf_t *cf, void *conf, RSA *key, json_t **jwk);
//static char *ngx_http_acme_create_priv_jwk(ngx_conf_t *cf, void *conf, RSA *key, json_t **jwk);
static char *ngx_http_acme_read_jwk(ngx_conf_t *cf, void *conf, ngx_str_t jwk_str, RSA **key);
static char *ngx_http_acme_json_request(ngx_conf_t *cf, void *conf, char *url, ngx_http_acme_http_method_t http_method,
json_t *request_json, json_t **response_json, ngx_http_acme_slist_t **response_headers);
static char *ngx_http_acme_plain_request(ngx_conf_t *cf, void *conf, char *url, ngx_http_acme_http_method_t http_method,
ngx_str_t request_data, ngx_str_t *response_data, ngx_http_acme_slist_t **response_headers);
static size_t ngx_http_acme_header_callback(char *buffer, size_t size, size_t nitems, void *userdata);
static ngx_int_t ngx_http_acme_init(ngx_conf_t *cf);
//static ngx_http_acme_sdict_t *ngx_http_acme_sdict_append_kv_pair(ngx_http_acme_sdict_t *sdict, ngx_str_t key, ngx_str_t value);
//static void ngx_http_acme_sdict_free_all(ngx_http_acme_sdict_t *sdict);
static ngx_http_acme_slist_t *ngx_http_acme_slist_append_entry(ngx_http_acme_slist_t *slist, ngx_str_t value);
static void ngx_http_acme_slist_free_all(ngx_http_acme_slist_t *slist);
/**
* This module provided directive: acme.
*
*/
static ngx_command_t ngx_http_acme_commands[] = {
{ ngx_string("acme"), /* directive */
NGX_HTTP_SRV_CONF|NGX_CONF_NOARGS, /* location context and takes
no arguments*/
ngx_http_acme, /* configuration setup function */
0, /* No offset. Only one context is supported. */
0, /* No offset when storing the module configuration on struct. */
NULL},
ngx_null_command /* command termination */
};
/* The module context. */
static ngx_http_module_t ngx_http_acme_module_ctx = {
NULL, /* preconfiguration */
ngx_http_acme_init, /* postconfiguration */
NULL, /* create main configuration */
NULL, /* init main configuration */
NULL, /* create server configuration */
NULL, /* merge server configuration */
NULL, /* create location configuration */
NULL /* merge location configuration */
};
/* Module definition. */
ngx_module_t ngx_http_acme_module = {
NGX_MODULE_V1,
&ngx_http_acme_module_ctx, /* module context */
ngx_http_acme_commands, /* module directives */
NGX_HTTP_MODULE, /* module type */
NULL, /* init master */
NULL, /* init module */
NULL, /* init process */
NULL, /* init thread */
NULL, /* exit thread */
NULL, /* exit process */
NULL, /* exit master */
NGX_MODULE_V1_PADDING
};
/**
* Configuration setup function that installs the content handler.
*
* @param cf
* Module configuration structure pointer.
* @param cmd
* Module directives structure pointer.
* @param conf
* Module configuration structure pointer.
* @return string
* Status of the configuration setup.
*/
static char *ngx_http_acme(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
ngx_http_ssl_srv_conf_t *sscf; /* pointer to core location configuration */
int ret;
// TODO (KK) Pull the different parts out as own methods for readability
/*
* TODO (KK) Get the config directory path (e.g. /etc/nginx)
*/
/*
* TODO (KK) Init acme dir (mkdirs)
*/
/*
* ACME communication - getting a certificate
*/
if(ngx_http_acme_main(cf, conf) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while gathering certificate from ACME server");
return NGX_CONF_ERROR;
}
/*
* TODO (KK) Install certificate (right now it just copies an example cert)
*/
{
ngx_copy_file_t cpyf;
ngx_log_error(NGX_LOG_NOTICE, cf->log, 0, "Installing certificate and key");
cpyf.size = -1;
cpyf.buf_size = 0;
cpyf.access = NGX_FILE_DEFAULT_ACCESS;
cpyf.time = -1;
cpyf.log = cf->log;
/* Copy certificate */
ret = ngx_copy_file((u_char *)ACME_DEV_FROM_CERT_PATH, (u_char *)ACME_DEV_CERT_PATH, &cpyf);
/* Copy private key */
if(ret == NGX_OK) {
/* Only 0600 access for private key */
cpyf.access = NGX_FILE_OWNER_ACCESS;
ret = ngx_copy_file((u_char *)ACME_DEV_FROM_KEY_PATH, (u_char *)ACME_DEV_KEY_PATH, &cpyf);
}
if(ret != NGX_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Installing the certificate or private key failed");
return NGX_CONF_ERROR;
}
}
/*
* Fool the SSL module into using the ACME certificates
*/
/* Get SSL module configuration */
sscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_ssl_module);
// TODO (KK) Report warning when ssl configs are not set (acme w/o ssl activated in the same server context is an error)
// --> Maybe ignore acme config then and issue a warning
if(sscf) {
// ngx_log_error(NGX_LOG_NOTICE, cf->log, 0, "Found SSL certificate path: %s", sscf->certificate.data);
/* Spoof SSL cert */
sscf->certificates = ngx_array_create(cf->pool, 4, sizeof(ngx_str_t));
if (sscf->certificates == NULL) {
return NGX_CONF_ERROR;
}
((ngx_str_t *) sscf->certificates->elts)[0] = (ngx_str_t) ngx_string(ACME_DIR "/" ACME_LIVE_DIR "/" ACME_DEV_SERVER_NAME "/" ACME_CERT);
/* Spoof SSL cert key */
sscf->certificate_keys = ngx_array_create(cf->pool, 4, sizeof(ngx_str_t));
if (sscf->certificate_keys == NULL) {
return NGX_CONF_ERROR;
}
((ngx_str_t *) sscf->certificate_keys->elts)[0] = (ngx_str_t) ngx_string(ACME_DIR "/" ACME_LIVE_DIR "/" ACME_DEV_SERVER_NAME "/" ACME_CERT);
}
return NGX_CONF_OK;
} /* ngx_http_acme */
static char *ngx_http_acme_main(ngx_conf_t *cf, void *conf)
{
/*
* Function's logic in pseudo code:
*
* if (certificate file exists) {
* if (cert is not expired) {
* return
* }
* }
*
* if (no account key exists) {
* create account key
* } else {
* load account key from file
* }
*
* if (there is no registration for this account key on the ACME server) {
* register
* }
*
* if (there is no authorization for this domain on this ACME account) {
* authorize and solve the challenges
* }
*
* if (the certificate exists but is expired) {
* renew cert and return
* }
*
* get the certificate from the server and return
*
*/
int ret;
ngx_str_t replay_nonce = ngx_null_string;
/*
* Load key pair for ACME account
*/
RSA *rsa = NULL;
/* TODO (KK) Extract to own method */
if(1 /* if no account key exists */)
{
/*
* Generate new key pair
*/
BIGNUM *e = NULL;
ngx_log_error(NGX_LOG_NOTICE, cf->log, 0, "Generate RSA key");
// TODO (KK) Change key type to EVP_PKEY everywhere for being able to handle other keys than RSA
rsa = RSA_new();
ret = BN_dec2bn(&e, ACME_ACCOUNT_RSA_EXP);
if(ret == 0) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error creating the account key. OpenSSL error 0x%xl", ERR_get_error());
return NGX_CONF_ERROR;
}
ret = RSA_generate_key_ex(rsa, ACME_ACCOUNT_RSA_BITS, e, NULL);
if(ret == 0) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error creating the account key. OpenSSL error 0x%xl", ERR_get_error());
return NGX_CONF_ERROR;
}
// TODO (KK) Save account key in file
// ngx_http_acme_create_priv_jwk(ngx_conf_t *cf, void *conf, RSA *key, json_t **jwk)
BN_free(e);
} else {
/*
* Load existing account key from file
*/
// TODO (KK) Read JWK file to a string (and free it afterwards)
if(ngx_http_acme_read_jwk(cf, conf, (ngx_str_t)ngx_null_string, &rsa) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Failed to load the account key from file");
return NGX_CONF_ERROR;
}
}
/* Fetch ACME dir - just to retrieve a replay nonce */
if(ngx_http_acme_fetch_dir(cf, conf, &replay_nonce) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Failed to make directory request");
return NGX_CONF_ERROR;
}
/* Register an account */
if(ngx_http_acme_new_reg(cf, conf, &replay_nonce, rsa) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Failed to register");
return NGX_CONF_ERROR;
}
/* Authorize for domain */
if(ngx_http_acme_new_auth(cf, conf, &replay_nonce, rsa) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Failed to authorize");
return NGX_CONF_ERROR;
}
// json_t *test_obj;
// json_t *test_output;
//
// /* TODO (KK) Test - remove later: Send request data */
// test_obj = json_pack("{s:s}", "test", "Test string");
// if(ngx_http_acme_json_request(cf, conf, "http://www.foaas.com/operations", GET, json_null(), &test_output, NULL) != NGX_CONF_OK) {
// ngx_log_error(NGX_LOG_ERR, cf->log, 0, "JSON request failed");
// return NGX_CONF_ERROR;
// }
//
// char *output_str = json_dumps(test_output, 0);
// println_debug("Returned JSON string: ", &((ngx_str_t)ngx_string_dynamic(output_str)));
//
// json_decref(test_obj);
// json_decref(test_output);
//
// /* TODO (KK) Test - remove later: Sign off JSON */
// test_obj = json_pack("{s:s}", "test", "Test string");
// if(ngx_http_acme_sign_json(cf, conf, test_obj, rsa, replay_nonce, &test_output) != NGX_CONF_OK) {
// ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Creating JWS failed");
// return NGX_CONF_ERROR;
// }
//
// output_str = json_dumps(test_output, 0);
// println_debug("JWS string: ", &((ngx_str_t)ngx_string_dynamic(output_str)));
//
// json_decref(test_obj);
// json_decref(test_output);
// ngx_free(output_str);
RSA_free(rsa);
return NGX_CONF_OK;
} /* ngx_http_acme_main */
static char *ngx_http_acme_fetch_dir(ngx_conf_t *cf, void *conf, ngx_str_t *replay_nonce)
{
json_t *response_json;
ngx_http_acme_slist_t *response_headers = NULL;
/* Make JSON request */
if(ngx_http_acme_request(cf, conf, ACME_SERVER "/directory", GET, json_null(), NULL, replay_nonce, &response_json, &response_headers) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while making JSON request");
return NGX_CONF_ERROR;
}
ngx_http_acme_slist_free_all(response_headers);
json_decref(response_json);
return NGX_CONF_OK;
} /* ngx_http_acme_fetch_dir */
static char *ngx_http_acme_new_reg(ngx_conf_t *cf, void *conf, ngx_str_t *replay_nonce, RSA *key)
{
json_t *request_json;
json_t *response_json;
ngx_http_acme_slist_t *response_headers = NULL;
ngx_http_acme_slist_t *response_headers2 = NULL;
ngx_http_acme_slist_t *header = NULL;
ngx_str_t tos_url = ngx_null_string;
char *reg_location = NULL;
size_t reg_location_len = 0;
char *tmp, *max_addr, *min_addr;
/* Assemble request */
request_json = json_pack("{s:s}", "resource", "new-reg");
/* Make JSON request */
if(ngx_http_acme_request(cf, conf, ACME_SERVER "/acme/new-reg", POST, request_json, key, replay_nonce, &response_json, &response_headers) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while making JSON request");
return NGX_CONF_ERROR;
}
/* Process response */
/* Search for and extract the location of the registration object */
for(header = response_headers; header != NULL; header = header->next) {
if(header->value_len < strlen(ACME_LOCATION_HEADER_PREFIX_STRING))
continue;
if(ngx_strncmp(header->value, ACME_LOCATION_HEADER_PREFIX_STRING, strlen(ACME_LOCATION_HEADER_PREFIX_STRING)) == 0) {
/* Location header found, extract it */
reg_location_len = header->value_len - strlen(ACME_LOCATION_HEADER_PREFIX_STRING) + 1 /* for terminating null character */;
reg_location = ngx_alloc(reg_location_len, cf->log);
ngx_memcpy(reg_location, header->value + strlen(ACME_LOCATION_HEADER_PREFIX_STRING), reg_location_len - 1);
reg_location[reg_location_len - 1] = '\0';
break;
}
}
if(header == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Location of registration object not found in HTTP response headers");
return NGX_CONF_ERROR;
}
/*
* Terms of service agreement
*/
/* Search for and extract terms-of-service url from response headers */
for(header = response_headers; header != NULL; header = header->next) {
/* Check minimum length */
if(header->value_len < strlen(ACME_TOS_PREFIX_STRING ACME_TOS_SUFFIX_STRING))
continue;
/* Check prefix */
if(ngx_strncmp(header->value, ACME_TOS_PREFIX_STRING, strlen(ACME_TOS_PREFIX_STRING)) != 0)
continue;
/* Search backwards */
min_addr = header->value + strlen(ACME_TOS_PREFIX_STRING);
max_addr = header->value + header->value_len - strlen(ACME_TOS_SUFFIX_STRING);
for(tmp = max_addr; tmp >= min_addr; tmp--) {
if(ngx_strncmp(tmp, ACME_TOS_SUFFIX_STRING, strlen(ACME_TOS_SUFFIX_STRING)) == 0) {
goto found;
}
}
}
/* No terms-of-service link found, so we don't need to agree to anything */
goto new_reg_end;
found:
tos_url.data = (u_char *) min_addr;
tos_url.len = tmp - min_addr;
/* Send a registration update to agree to the TOS */
/* Free local variables before reusing them */
json_decref(request_json);
json_decref(response_json);
/* Assemble request */
request_json = json_pack("{s:s,s:s%}", "resource", "reg", "agreement", tos_url.data, tos_url.len);
/* Make JSON request */
if(ngx_http_acme_request(cf, conf, reg_location, POST, request_json, key, replay_nonce, &response_json, &response_headers2) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while making JSON request");
return NGX_CONF_ERROR;
}
ngx_http_acme_slist_free_all(response_headers2);
new_reg_end:
ngx_free(reg_location);
json_decref(request_json);
json_decref(response_json);
ngx_http_acme_slist_free_all(response_headers);
return NGX_CONF_OK;
} /* ngx_http_acme_new_reg */
static char *ngx_http_acme_new_auth(ngx_conf_t *cf, void *conf, ngx_str_t *replay_nonce, RSA *key)
{
json_t *request_json;
json_t *response_json;
ngx_http_acme_slist_t *response_headers = NULL;
/* Assemble request */
request_json = json_pack("{s:s, s:{s:s, s:s} }", "resource", "new-authz",
"identifier", "type", "dns", "value", ACME_DEV_SERVER_NAME);
/* Make JSON request */
if(ngx_http_acme_request(cf, conf, ACME_SERVER "/acme/new-authz", POST, request_json, key, replay_nonce, &response_json, &response_headers) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while making JSON request");
return NGX_CONF_ERROR;
}
/* Process response */
json_decref(request_json);
json_decref(response_json);
ngx_http_acme_slist_free_all(response_headers);
return NGX_CONF_OK;
} /* ngx_http_acme_new_auth */
static char *ngx_http_acme_request(ngx_conf_t *cf, void *conf, char *url, ngx_http_acme_http_method_t http_method,
json_t *request_json, RSA *key, ngx_str_t *replay_nonce, json_t **response_json,
ngx_http_acme_slist_t **response_headers)
{
json_t *signed_request_json;
ngx_http_acme_slist_t *header = NULL;
/* Sign JSON and create JWS from the request JSON data */
if(json_is_null(request_json)) {
signed_request_json = json_null();
} else {
if(ngx_http_acme_sign_json(cf, conf, request_json, key, *replay_nonce, &signed_request_json) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Creating JWS failed");
return NGX_CONF_ERROR;
}
}
/* Make JSON request */
if(ngx_http_acme_json_request(cf, conf, url, http_method, signed_request_json, response_json, response_headers) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while making JSON request");
return NGX_CONF_ERROR;
}
if(replay_nonce->data != NULL)
ngx_free(replay_nonce->data);
ngx_str_null(replay_nonce);
json_decref(signed_request_json);
/* Search for and extract replay nonce from response headers */
for(header = *response_headers; header != NULL; header = header->next) {
if(header->value_len < strlen(ACME_REPLAY_NONCE_PREFIX_STRING))
continue;
if(ngx_strncmp(header->value, ACME_REPLAY_NONCE_PREFIX_STRING, strlen(ACME_REPLAY_NONCE_PREFIX_STRING)) == 0) {
/* Replay nonce found, extract it */
replay_nonce->len = header->value_len - strlen(ACME_REPLAY_NONCE_PREFIX_STRING);
replay_nonce->data = ngx_alloc(replay_nonce->len, cf->log);
ngx_memcpy(replay_nonce->data, header->value + strlen(ACME_REPLAY_NONCE_PREFIX_STRING), replay_nonce->len);
break;
}
}
if(header == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "No Replay-Nonce found in HTTP response headers");
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
} /* ngx_http_acme_create_jwk */
static char *ngx_http_acme_sign_json(ngx_conf_t *cf, void *conf, json_t *payload, RSA *key, ngx_str_t replay_nonce, json_t **flattened_jws)
{
/*
* Structure according to RFC7515:
*
* {
* "payload":"<payload contents>",
* "protected":"<integrity-protected header contents>",
* "header":<non-integrity-protected header contents>,
* "signature":"<signature contents>"
* }
*
* Example:
*
* {
* "payload":
* "eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFtcGxlLmNvbS9pc19yb290Ijp0cnVlfQ",
* "protected":"eyJhbGciOiJFUzI1NiJ9",
* "header": {"kid":"e9bc097a-ce51-4036-9562-d2ade882db0d"},
* "signature":
* "DtEhU3ljbEg8L38VWAfUAqOyKAM6-Xx-F4GawxaepmXFCgfTjDxw5djxLa8ISlSApmWQxfKTUJqPP3-Kg6NU1Q"
* }
*/
/*
* ACME restrictions:
* The JWS MUST use the Flattened JSON Serialization
* The JWS MUST be encoded using UTF-8
* The JWS Header or Protected Header MUST include “alg” and “jwk” fields
* The JWS MUST NOT have the value “none” in its “alg” field
*/
json_t *jwk;
json_t *header;
ngx_str_t encoded_protected_header, serialized_payload, encoded_payload, tmp;
ngx_str_t signing_input, signature, encoded_signature;
u_char *tmp_char_p;
/* Variables for signing */
EVP_PKEY *evp_key;
EVP_MD_CTX *mdctx = NULL;
int ret = 0;
/*
* Encode payload
*/
serialized_payload = (ngx_str_t)ngx_string_dynamic(json_dumps(payload, 0));
encoded_payload.len = ngx_base64_encoded_length(serialized_payload.len);
encoded_payload.data = ngx_alloc(encoded_payload.len, cf->log);
ngx_encode_base64url(&encoded_payload, &serialized_payload);
println_debug("Signing payload: ", &serialized_payload);
/*
* Create header
*/
/* jwk header */
if(ngx_http_acme_create_jwk(cf, conf, key, &jwk) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Failed to create the JWK from the account key");
ngx_free(serialized_payload.data);
ngx_free(encoded_payload.data);
return NGX_CONF_ERROR;
}
/* Pack header into JSON */
header = json_pack("{s:s, s:s%, s:o}", "alg", "RS256", "nonce", replay_nonce.data, replay_nonce.len, "jwk", jwk);
if(header == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error packing JWS header");
ngx_free(serialized_payload.data);
ngx_free(encoded_payload.data);
return NGX_CONF_ERROR;
}
/* Serialize and base64url encode header */
tmp = (ngx_str_t)ngx_string_dynamic(json_dumps(header, 0));
encoded_protected_header.len = ngx_base64_encoded_length(tmp.len);
encoded_protected_header.data = ngx_alloc(encoded_protected_header.len, cf->log);
ngx_encode_base64url(&encoded_protected_header, &tmp);
ngx_free(tmp.data);
json_decref(header);
/*
* Create signature
*/
/* Create signing input */
/* = ASCII(BASE64URL(UTF8(JWS Protected Header)) || '.' || BASE64URL(JWS Payload)) */
signing_input.len = encoded_protected_header.len + strlen(".") + encoded_payload.len;
signing_input.data = ngx_alloc(signing_input.len, cf->log);
tmp_char_p = ngx_copy(signing_input.data, encoded_protected_header.data, encoded_protected_header.len);
tmp_char_p = ngx_copy(tmp_char_p, ".", strlen("."));
tmp_char_p = ngx_copy(tmp_char_p, encoded_payload.data, encoded_payload.len);
/* Convert the RSA key to the EVP_PKEY structure */
evp_key = EVP_PKEY_new();
if(evp_key == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error signing the message digest for the JWS signature.");
return NGX_CONF_ERROR;
}
if(EVP_PKEY_set1_RSA(evp_key, key) == 0) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error signing the message digest for the JWS signature.");
return NGX_CONF_ERROR;
}
/* Create the message digest context */
ret = 0;
mdctx = EVP_MD_CTX_create();
if(mdctx == NULL)
goto err;
/* Initialize the DigestSign operation - SHA-256 has been selected as the message digest function */
if(EVP_DigestSignInit(mdctx, NULL, EVP_sha256(), NULL, evp_key) != 1)
goto err;
/* Call update with the message */
if(EVP_DigestSignUpdate(mdctx, signing_input.data, signing_input.len) != 1)
goto err;
/* Finalise the DigestSign operation */
/* First call EVP_DigestSignFinal with a NULL sig parameter to obtain the length of the */
/* signature. The length is returned in siglen. */
if(EVP_DigestSignFinal(mdctx, NULL, &signature.len) != 1)
goto err;
/* Allocate memory for the signature */
signature.data = ngx_alloc(signature.len, cf->log);
/* Obtain the signature */
if(EVP_DigestSignFinal(mdctx, signature.data, &signature.len) != 1)
goto err;
/* Success */
ret = 1;
err:
if(ret != 1) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error signing the message digest for the JWS signature. OpenSSL error 0x%xl", ERR_get_error());
return NGX_CONF_ERROR;
}
/* Clean up */
EVP_MD_CTX_destroy(mdctx);
EVP_PKEY_free(evp_key);
/* base64url encode the signature */
encoded_signature.len = ngx_base64_encoded_length(signature.len);
encoded_signature.data = ngx_alloc(encoded_signature.len, cf->log);
ngx_encode_base64url(&encoded_signature, &signature);
ngx_free(signature.data);
/*
* Create flattened JWS serialization
*/
*flattened_jws = json_pack("{s:s%,s:s%,s:s%}",
"payload", encoded_payload.data, encoded_payload.len,
"protected", encoded_protected_header.data, encoded_protected_header.len,
"signature", encoded_signature.data, encoded_signature.len
);
ngx_free(serialized_payload.data);
// TODO (KK) Maybe this is too early for a free since the strings will be used in the flattened JWS (but when to free then?)
ngx_free(encoded_payload.data);
ngx_free(encoded_protected_header.data);
ngx_free(encoded_signature.data);
if(*flattened_jws == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error serializing flattened JWS");
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
} /* ngx_http_acme_sign_json */
static char *ngx_http_acme_create_jwk(ngx_conf_t *cf, void *conf, RSA *key, json_t **jwk)
{
ngx_str_t e, n, tmp;
/* Baser64url encode e */
tmp.len = BN_num_bytes(key->e);
tmp.data = ngx_alloc(tmp.len, cf->log);
tmp.len = BN_bn2bin(key->e, tmp.data);
e.len = ngx_base64_encoded_length(tmp.len);
e.data = ngx_alloc(e.len, cf->log);
ngx_encode_base64url(&e, &tmp);
ngx_free(tmp.data);
/* Baser64url encode n */
tmp.len = BN_num_bytes(key->n);
tmp.data = ngx_alloc(tmp.len, cf->log);
tmp.len = BN_bn2bin(key->n, tmp.data);
n.len = ngx_base64_encoded_length(tmp.len);
n.data = ngx_alloc(n.len, cf->log);
ngx_encode_base64url(&n, &tmp);
ngx_free(tmp.data);
*jwk = json_pack("{s:s, s:s%, s:s%}", "kty", "RSA", "e", e.data, e.len, "n", n.data, n.len);
if(*jwk == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Failed to pack JWK");
return NGX_CONF_ERROR;
}
ngx_free(e.data);
ngx_free(n.data);
return NGX_CONF_OK;
} /* ngx_http_acme_create_jwk */
//static char *ngx_http_acme_create_priv_jwk(ngx_conf_t *cf, void *conf, RSA *key, json_t **jwk)
//{
// // TODO (KK) Create JWK with following information
// // d, e, n, q, p, qi, dp, dq
// // kty: RSA
//
// return NGX_CONF_OK;
//} /* ngx_http_acme_create_priv_jwk */
static char *ngx_http_acme_read_jwk(ngx_conf_t *cf, void *conf, ngx_str_t jwk_str, RSA **key)
{
json_t *jwk;
json_error_t error;
/*
* Deserialize JWK
*/
jwk = json_loadb((char *) jwk_str.data, jwk_str.len, 0, &error);
free(jwk_str.data);
ngx_str_null(&jwk_str);
if(jwk == NULL)
{
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error parsing JSON: on line %d: %s\n", error.line, error.text);
return NGX_CONF_ERROR;
}
// TODO (KK) Form RSA struct from JWK
return NGX_CONF_OK;
} /* ngx_http_acme_create_jwk */
static char *ngx_http_acme_json_request(ngx_conf_t *cf, void *conf, char *url, ngx_http_acme_http_method_t http_method,
json_t *request_json, json_t **response_json, ngx_http_acme_slist_t **response_headers)
{
ngx_str_t response_data;
ngx_str_t request_data;
char *tmp;
json_error_t error;
/* Convert request_json to string to provide it to the following method */
request_data = (ngx_str_t)ngx_null_string;
if(!json_is_null(request_json)) {
tmp = json_dumps(request_json, 0);
if(tmp == NULL) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while creating request string from JSON\n");
return NGX_CONF_ERROR;
} else {
request_data.data = (u_char *)tmp;
request_data.len = ngx_strlen(tmp);
}
}
/* Make request */
if(ngx_http_acme_plain_request(cf, conf, url, http_method, request_data, &response_data, response_headers) != NGX_CONF_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0, "Error while making request\n");
return NGX_CONF_ERROR;
}
/* Now all the returned JSON is in the data variable */
/*
* Parsing returned JSON
*/
/* Begin Jansson part */
if(response_data.len <= 0) {
*response_json = json_null();
} else {
*response_json = json_loadb((char *) response_data.data, response_data.len, 0, &error);
}
free(response_data.data);
ngx_str_null(&response_data);
if(*response_json == NULL)
{
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error parsing JSON: on line %d: %s\n", error.line, error.text);
return NGX_CONF_ERROR;
}
/* End Jansson part */
return NGX_CONF_OK;
} /* ngx_http_acme_json_request */
static char *ngx_http_acme_plain_request(ngx_conf_t *cf, void *conf, char *url, ngx_http_acme_http_method_t http_method,
ngx_str_t request_data, ngx_str_t *response_data, ngx_http_acme_slist_t **response_headers)
{
CURL *curl;
CURLcode res;
struct curl_slist *request_headers = NULL;
FILE *response_data_stream;
/* Begin cURL part */
curl_global_init(CURL_GLOBAL_DEFAULT);
curl = curl_easy_init();
if(curl == NULL)
return NGX_CONF_ERROR;
curl_easy_setopt(curl, CURLOPT_URL, url);
/*
* Setting the HTTP method
*/
if(http_method == GET) {
curl_easy_setopt(curl, CURLOPT_HTTPGET, 1L);
} else if(http_method == POST) {
curl_easy_setopt(curl, CURLOPT_POST, 1L);
}
/*
* Setting the request data handling
*/
if(request_data.data != NULL) {
// TODO (KK) Add method parameter for the header list to be dynamic in e.g. the content type, since it doesn't always have to be JSON ;)
request_headers = curl_slist_append(request_headers, "Content-Type: application/json");
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, request_headers);
/* size of the data to copy from the buffer and send in the request */
curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, request_data.len);
/* send data from the local stack */
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, request_data.data);
println_debug("Request data: ", &request_data);
}
/*
* Setting the response data handling
*/
/* Setup the stream for the response data */
response_data_stream = open_memstream((char **) &response_data->data, &response_data->len);
if(response_data_stream == NULL) {
curl_slist_free_all(request_headers);
curl_easy_cleanup(curl);
return NGX_CONF_ERROR;
}
/*
* ATTENTION: Setting CURLOPT_WRITEDATA without CURLOPT_WRITEFUNCTION does not work on Windows
* according to https://curl.haxx.se/libcurl/c/CURLOPT_WRITEDATA.html
*/
curl_easy_setopt(curl, CURLOPT_WRITEDATA, response_data_stream);
/*
* Setting the response header handling
*/
if (response_headers != NULL) {
curl_easy_setopt(curl, CURLOPT_HEADERDATA, response_headers);
curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION,
ngx_http_acme_header_callback);
}
/*
* Perform the request
*/
res = curl_easy_perform(curl);
/* Check for errors */
if(res != CURLE_OK) {
ngx_log_error(NGX_LOG_ERR, cf->log, 0,
"Error while performing request: %s\n", curl_easy_strerror(res));
fclose(response_data_stream);
curl_slist_free_all(request_headers);
curl_easy_cleanup(curl);
return NGX_CONF_ERROR;
}
/* always cleanup */
curl_easy_cleanup(curl);
fclose(response_data_stream);
/* free the custom headers */
curl_slist_free_all(request_headers);
/* End cURL part */
println_debug("Response data: ", response_data);
return NGX_CONF_OK;
} /* ngx_http_acme_plain_request */
static size_t ngx_http_acme_header_callback(char *buffer, size_t size, size_t nitems, void *userdata)
{
ngx_http_acme_slist_t **slist = (ngx_http_acme_slist_t **) userdata;
ngx_str_t entry;
if(size * nitems <= 0)
return 0;
/* Subtract 2 from the length to trim off the \r\n */
entry.len = (size * nitems) - 2;
entry.data = (u_char *) buffer;
*slist = ngx_http_acme_slist_append_entry(*slist, entry);
if(*slist == NULL)
return 0;
return nitems * size;
} /* ngx_http_acme_header_callback */