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1 | // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- | |
2 | // vim: ts=8 sw=2 smarttab | |
3 | ||
4 | #include <algorithm> | |
5 | #include <map> | |
6 | #include <iterator> | |
7 | #include <string> | |
8 | #include <vector> | |
9 | ||
10 | #include "common/armor.h" | |
11 | #include "common/utf8.h" | |
12 | #include "rgw_auth_s3.h" | |
13 | #include "rgw_common.h" | |
14 | #include "rgw_client_io.h" | |
15 | #include "rgw_rest.h" | |
16 | #include "rgw_crypt_sanitize.h" | |
17 | ||
18 | #include <boost/container/small_vector.hpp> | |
19 | #include <boost/utility/string_view.hpp> | |
20 | ||
21 | #define dout_context g_ceph_context | |
22 | #define dout_subsys ceph_subsys_rgw | |
23 | ||
24 | static const auto signed_subresources = { | |
25 | "acl", | |
26 | "cors", | |
27 | "delete", | |
28 | "lifecycle", | |
29 | "location", | |
30 | "logging", | |
31 | "notification", | |
32 | "partNumber", | |
33 | "policy", | |
34 | "requestPayment", | |
35 | "response-cache-control", | |
36 | "response-content-disposition", | |
37 | "response-content-encoding", | |
38 | "response-content-language", | |
39 | "response-content-type", | |
40 | "response-expires", | |
41 | "tagging", | |
42 | "torrent", | |
43 | "uploadId", | |
44 | "uploads", | |
45 | "versionId", | |
46 | "versioning", | |
47 | "versions", | |
48 | "website" | |
49 | }; | |
50 | ||
51 | /* | |
52 | * ?get the canonical amazon-style header for something? | |
53 | */ | |
54 | ||
55 | static std::string | |
56 | get_canon_amz_hdr(const std::map<std::string, std::string>& meta_map) | |
57 | { | |
58 | std::string dest; | |
59 | ||
60 | for (const auto& kv : meta_map) { | |
61 | dest.append(kv.first); | |
62 | dest.append(":"); | |
63 | dest.append(kv.second); | |
64 | dest.append("\n"); | |
65 | } | |
66 | ||
67 | return dest; | |
68 | } | |
69 | ||
70 | /* | |
71 | * ?get the canonical representation of the object's location | |
72 | */ | |
73 | static std::string | |
74 | get_canon_resource(const char* const request_uri, | |
75 | const std::map<std::string, std::string>& sub_resources) | |
76 | { | |
77 | std::string dest; | |
78 | ||
79 | if (request_uri) { | |
80 | dest.append(request_uri); | |
81 | } | |
82 | ||
83 | bool initial = true; | |
84 | for (const auto& subresource : signed_subresources) { | |
85 | const auto iter = sub_resources.find(subresource); | |
86 | if (iter == std::end(sub_resources)) { | |
87 | continue; | |
88 | } | |
89 | ||
90 | if (initial) { | |
91 | dest.append("?"); | |
92 | initial = false; | |
93 | } else { | |
94 | dest.append("&"); | |
95 | } | |
96 | ||
97 | dest.append(iter->first); | |
98 | if (! iter->second.empty()) { | |
99 | dest.append("="); | |
100 | dest.append(iter->second); | |
101 | } | |
102 | } | |
103 | ||
104 | dout(10) << "get_canon_resource(): dest=" << dest << dendl; | |
105 | return dest; | |
106 | } | |
107 | ||
108 | /* | |
109 | * get the header authentication information required to | |
110 | * compute a request's signature | |
111 | */ | |
112 | void rgw_create_s3_canonical_header( | |
113 | const char* const method, | |
114 | const char* const content_md5, | |
115 | const char* const content_type, | |
116 | const char* const date, | |
117 | const std::map<std::string, std::string>& meta_map, | |
118 | const char* const request_uri, | |
119 | const std::map<std::string, std::string>& sub_resources, | |
120 | std::string& dest_str) | |
121 | { | |
122 | std::string dest; | |
123 | ||
124 | if (method) { | |
125 | dest = method; | |
126 | } | |
127 | dest.append("\n"); | |
128 | ||
129 | if (content_md5) { | |
130 | dest.append(content_md5); | |
131 | } | |
132 | dest.append("\n"); | |
133 | ||
134 | if (content_type) { | |
135 | dest.append(content_type); | |
136 | } | |
137 | dest.append("\n"); | |
138 | ||
139 | if (date) { | |
140 | dest.append(date); | |
141 | } | |
142 | dest.append("\n"); | |
143 | ||
144 | dest.append(get_canon_amz_hdr(meta_map)); | |
145 | dest.append(get_canon_resource(request_uri, sub_resources)); | |
146 | ||
147 | dest_str = dest; | |
148 | } | |
149 | ||
150 | static inline bool is_base64_for_content_md5(unsigned char c) { | |
151 | return (isalnum(c) || isspace(c) || (c == '+') || (c == '/') || (c == '=')); | |
152 | } | |
153 | ||
154 | /* | |
155 | * get the header authentication information required to | |
156 | * compute a request's signature | |
157 | */ | |
158 | bool rgw_create_s3_canonical_header(const req_info& info, | |
159 | utime_t* const header_time, | |
160 | std::string& dest, | |
161 | const bool qsr) | |
162 | { | |
163 | const char* const content_md5 = info.env->get("HTTP_CONTENT_MD5"); | |
164 | if (content_md5) { | |
165 | for (const char *p = content_md5; *p; p++) { | |
166 | if (!is_base64_for_content_md5(*p)) { | |
167 | dout(0) << "NOTICE: bad content-md5 provided (not base64)," | |
168 | << " aborting request p=" << *p << " " << (int)*p << dendl; | |
169 | return false; | |
170 | } | |
171 | } | |
172 | } | |
173 | ||
174 | const char *content_type = info.env->get("CONTENT_TYPE"); | |
175 | ||
176 | std::string date; | |
177 | if (qsr) { | |
178 | date = info.args.get("Expires"); | |
179 | } else { | |
180 | const char *str = info.env->get("HTTP_X_AMZ_DATE"); | |
181 | const char *req_date = str; | |
182 | if (str == NULL) { | |
183 | req_date = info.env->get("HTTP_DATE"); | |
184 | if (!req_date) { | |
185 | dout(0) << "NOTICE: missing date for auth header" << dendl; | |
186 | return false; | |
187 | } | |
188 | date = req_date; | |
189 | } | |
190 | ||
191 | if (header_time) { | |
192 | struct tm t; | |
193 | if (!parse_rfc2616(req_date, &t)) { | |
194 | dout(0) << "NOTICE: failed to parse date for auth header" << dendl; | |
195 | return false; | |
196 | } | |
197 | if (t.tm_year < 70) { | |
198 | dout(0) << "NOTICE: bad date (predates epoch): " << req_date << dendl; | |
199 | return false; | |
200 | } | |
201 | *header_time = utime_t(internal_timegm(&t), 0); | |
202 | } | |
203 | } | |
204 | ||
205 | const auto& meta_map = info.x_meta_map; | |
206 | const auto& sub_resources = info.args.get_sub_resources(); | |
207 | ||
208 | std::string request_uri; | |
209 | if (info.effective_uri.empty()) { | |
210 | request_uri = info.request_uri; | |
211 | } else { | |
212 | request_uri = info.effective_uri; | |
213 | } | |
214 | ||
215 | rgw_create_s3_canonical_header(info.method, content_md5, content_type, | |
216 | date.c_str(), meta_map, request_uri.c_str(), | |
217 | sub_resources, dest); | |
218 | return true; | |
219 | } | |
220 | ||
221 | ||
222 | namespace rgw { | |
223 | namespace auth { | |
224 | namespace s3 { | |
225 | ||
226 | /* FIXME(rzarzynski): duplicated from rgw_rest_s3.h. */ | |
227 | #define RGW_AUTH_GRACE_MINS 15 | |
228 | ||
229 | static inline int parse_v4_query_string(const req_info& info, /* in */ | |
230 | boost::string_view& credential, /* out */ | |
231 | boost::string_view& signedheaders, /* out */ | |
232 | boost::string_view& signature, /* out */ | |
233 | boost::string_view& date) /* out */ | |
234 | { | |
235 | /* auth ships with req params ... */ | |
236 | ||
237 | /* look for required params */ | |
238 | credential = info.args.get("X-Amz-Credential"); | |
239 | if (credential.size() == 0) { | |
240 | return -EPERM; | |
241 | } | |
242 | ||
243 | date = info.args.get("X-Amz-Date"); | |
244 | struct tm date_t; | |
245 | if (!parse_iso8601(sview2cstr(date).data(), &date_t, nullptr, false)) { | |
246 | return -EPERM; | |
247 | } | |
248 | ||
249 | /* Used for pre-signatured url, We shouldn't return -ERR_REQUEST_TIME_SKEWED | |
250 | * when current time <= X-Amz-Expires */ | |
251 | bool qsr = false; | |
252 | ||
253 | uint64_t now_req = 0; | |
254 | uint64_t now = ceph_clock_now(); | |
255 | ||
256 | boost::string_view expires = info.args.get("X-Amz-Expires"); | |
257 | if (!expires.empty()) { | |
258 | /* X-Amz-Expires provides the time period, in seconds, for which | |
259 | the generated presigned URL is valid. The minimum value | |
260 | you can set is 1, and the maximum is 604800 (seven days) */ | |
261 | time_t exp = atoll(expires.data()); | |
262 | if ((exp < 1) || (exp > 7*24*60*60)) { | |
263 | dout(10) << "NOTICE: exp out of range, exp = " << exp << dendl; | |
264 | return -EPERM; | |
265 | } | |
266 | /* handle expiration in epoch time */ | |
267 | now_req = (uint64_t)internal_timegm(&date_t); | |
268 | if (now >= now_req + exp) { | |
269 | dout(10) << "NOTICE: now = " << now << ", now_req = " << now_req << ", exp = " << exp << dendl; | |
270 | return -EPERM; | |
271 | } | |
272 | qsr = true; | |
273 | } | |
274 | ||
275 | if ((now_req < now - RGW_AUTH_GRACE_MINS * 60 || | |
276 | now_req > now + RGW_AUTH_GRACE_MINS * 60) && !qsr) { | |
277 | dout(10) << "NOTICE: request time skew too big." << dendl; | |
278 | dout(10) << "now_req = " << now_req << " now = " << now | |
279 | << "; now - RGW_AUTH_GRACE_MINS=" | |
280 | << now - RGW_AUTH_GRACE_MINS * 60 | |
281 | << "; now + RGW_AUTH_GRACE_MINS=" | |
282 | << now + RGW_AUTH_GRACE_MINS * 60 << dendl; | |
283 | return -ERR_REQUEST_TIME_SKEWED; | |
284 | } | |
285 | ||
286 | signedheaders = info.args.get("X-Amz-SignedHeaders"); | |
287 | if (signedheaders.size() == 0) { | |
288 | return -EPERM; | |
289 | } | |
290 | ||
291 | signature = info.args.get("X-Amz-Signature"); | |
292 | if (signature.size() == 0) { | |
293 | return -EPERM; | |
294 | } | |
295 | ||
296 | return 0; | |
297 | } | |
298 | ||
299 | namespace { | |
300 | static bool get_next_token(const boost::string_view& s, | |
301 | size_t& pos, | |
302 | const char* const delims, | |
303 | boost::string_view& token) | |
304 | { | |
305 | const size_t start = s.find_first_not_of(delims, pos); | |
306 | if (start == boost::string_view::npos) { | |
307 | pos = s.size(); | |
308 | return false; | |
309 | } | |
310 | ||
311 | size_t end = s.find_first_of(delims, start); | |
312 | if (end != boost::string_view::npos) | |
313 | pos = end + 1; | |
314 | else { | |
315 | pos = end = s.size(); | |
316 | } | |
317 | ||
318 | token = s.substr(start, end - start); | |
319 | return true; | |
320 | } | |
321 | ||
322 | template<std::size_t ExpectedStrNum> | |
323 | boost::container::small_vector<boost::string_view, ExpectedStrNum> | |
324 | get_str_vec(const boost::string_view& str, const char* const delims) | |
325 | { | |
326 | boost::container::small_vector<boost::string_view, ExpectedStrNum> str_vec; | |
327 | ||
328 | size_t pos = 0; | |
329 | boost::string_view token; | |
330 | while (pos < str.size()) { | |
331 | if (get_next_token(str, pos, delims, token)) { | |
332 | if (token.size() > 0) { | |
333 | str_vec.push_back(token); | |
334 | } | |
335 | } | |
336 | } | |
337 | ||
338 | return str_vec; | |
339 | } | |
340 | ||
341 | template<std::size_t ExpectedStrNum> | |
342 | boost::container::small_vector<boost::string_view, ExpectedStrNum> | |
343 | get_str_vec(const boost::string_view& str) | |
344 | { | |
345 | const char delims[] = ";,= \t"; | |
346 | return get_str_vec<ExpectedStrNum>(str, delims); | |
347 | } | |
348 | }; | |
349 | ||
350 | static inline int parse_v4_auth_header(const req_info& info, /* in */ | |
351 | boost::string_view& credential, /* out */ | |
352 | boost::string_view& signedheaders, /* out */ | |
353 | boost::string_view& signature, /* out */ | |
354 | boost::string_view& date) /* out */ | |
355 | { | |
356 | boost::string_view input(info.env->get("HTTP_AUTHORIZATION", "")); | |
357 | try { | |
358 | input = input.substr(::strlen(AWS4_HMAC_SHA256_STR) + 1); | |
359 | } catch (std::out_of_range&) { | |
360 | /* We should never ever run into this situation as the presence of | |
361 | * AWS4_HMAC_SHA256_STR had been verified earlier. */ | |
362 | dout(10) << "credentials string is too short" << dendl; | |
363 | return -EINVAL; | |
364 | } | |
365 | ||
366 | std::map<boost::string_view, boost::string_view> kv; | |
367 | for (const auto& s : get_str_vec<4>(input, ",")) { | |
368 | const auto parsed_pair = parse_key_value(s); | |
369 | if (parsed_pair) { | |
370 | kv[parsed_pair->first] = parsed_pair->second; | |
371 | } else { | |
372 | dout(10) << "NOTICE: failed to parse auth header (s=" << s << ")" | |
373 | << dendl; | |
374 | return -EINVAL; | |
375 | } | |
376 | } | |
377 | ||
378 | static const std::array<boost::string_view, 3> required_keys = { | |
379 | "Credential", | |
380 | "SignedHeaders", | |
381 | "Signature" | |
382 | }; | |
383 | ||
384 | /* Ensure that the presigned required keys are really there. */ | |
385 | for (const auto& k : required_keys) { | |
386 | if (kv.find(k) == std::end(kv)) { | |
387 | dout(10) << "NOTICE: auth header missing key: " << k << dendl; | |
388 | return -EINVAL; | |
389 | } | |
390 | } | |
391 | ||
392 | credential = kv["Credential"]; | |
393 | signedheaders = kv["SignedHeaders"]; | |
394 | signature = kv["Signature"]; | |
395 | ||
396 | /* sig hex str */ | |
397 | dout(10) << "v4 signature format = " << signature << dendl; | |
398 | ||
399 | /* ------------------------- handle x-amz-date header */ | |
400 | ||
401 | /* grab date */ | |
402 | ||
403 | const char *d = info.env->get("HTTP_X_AMZ_DATE"); | |
404 | struct tm t; | |
405 | if (!parse_iso8601(d, &t, NULL, false)) { | |
406 | dout(10) << "error reading date via http_x_amz_date" << dendl; | |
407 | return -EACCES; | |
408 | } | |
409 | date = d; | |
410 | ||
411 | return 0; | |
412 | } | |
413 | ||
414 | int parse_credentials(const req_info& info, /* in */ | |
415 | boost::string_view& access_key_id, /* out */ | |
416 | boost::string_view& credential_scope, /* out */ | |
417 | boost::string_view& signedheaders, /* out */ | |
418 | boost::string_view& signature, /* out */ | |
419 | boost::string_view& date, /* out */ | |
420 | bool& using_qs) /* out */ | |
421 | { | |
422 | const char* const http_auth = info.env->get("HTTP_AUTHORIZATION"); | |
423 | using_qs = http_auth == nullptr || http_auth[0] == '\0'; | |
424 | ||
425 | int ret; | |
426 | boost::string_view credential; | |
427 | if (using_qs) { | |
428 | ret = parse_v4_query_string(info, credential, signedheaders, | |
429 | signature, date); | |
430 | } else { | |
431 | ret = parse_v4_auth_header(info, credential, signedheaders, | |
432 | signature, date); | |
433 | } | |
434 | ||
435 | if (ret < 0) { | |
436 | return ret; | |
437 | } | |
438 | ||
439 | /* AKIAIVKTAZLOCF43WNQD/AAAAMMDD/region/host/aws4_request */ | |
440 | dout(10) << "v4 credential format = " << credential << dendl; | |
441 | ||
442 | if (std::count(credential.begin(), credential.end(), '/') != 4) { | |
443 | return -EINVAL; | |
444 | } | |
445 | ||
446 | /* credential must end with 'aws4_request' */ | |
447 | if (credential.find("aws4_request") == std::string::npos) { | |
448 | return -EINVAL; | |
449 | } | |
450 | ||
451 | /* grab access key id */ | |
452 | const size_t pos = credential.find("/"); | |
453 | access_key_id = credential.substr(0, pos); | |
454 | dout(10) << "access key id = " << access_key_id << dendl; | |
455 | ||
456 | /* grab credential scope */ | |
457 | credential_scope = credential.substr(pos + 1); | |
458 | dout(10) << "credential scope = " << credential_scope << dendl; | |
459 | ||
460 | return 0; | |
461 | } | |
462 | ||
463 | static inline bool char_needs_aws4_escaping(const char c) | |
464 | { | |
465 | if ((c >= 'a' && c <= 'z') || | |
466 | (c >= 'A' && c <= 'Z') || | |
467 | (c >= '0' && c <= '9')) { | |
468 | return false; | |
469 | } | |
470 | ||
471 | switch (c) { | |
472 | case '-': | |
473 | case '_': | |
474 | case '.': | |
475 | case '~': | |
476 | return false; | |
477 | } | |
478 | return true; | |
479 | } | |
480 | ||
481 | static inline std::string aws4_uri_encode(const std::string& src) | |
482 | { | |
483 | std::string result; | |
484 | ||
485 | for (const std::string::value_type c : src) { | |
486 | if (char_needs_aws4_escaping(c)) { | |
487 | rgw_uri_escape_char(c, result); | |
488 | } else { | |
489 | result.push_back(c); | |
490 | } | |
491 | } | |
492 | ||
493 | return result; | |
494 | } | |
495 | ||
496 | static inline std::string aws4_uri_recode(const boost::string_view& src) | |
497 | { | |
498 | std::string decoded = url_decode(src); | |
499 | return aws4_uri_encode(decoded); | |
500 | } | |
501 | ||
502 | std::string get_v4_canonical_qs(const req_info& info, const bool using_qs) | |
503 | { | |
504 | const std::string *params = &info.request_params; | |
505 | std::string copy_params; | |
506 | if (params->empty()) { | |
507 | /* Optimize the typical flow. */ | |
508 | return std::string(); | |
509 | } | |
510 | if (params->find_first_of('+') != std::string::npos) { | |
511 | copy_params = *params; | |
512 | boost::replace_all(copy_params, "+", " "); | |
513 | params = ©_params; | |
514 | } | |
515 | ||
516 | /* Handle case when query string exists. Step 3 described in: http://docs. | |
517 | * aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html */ | |
518 | std::map<std::string, std::string> canonical_qs_map; | |
519 | for (const auto& s : get_str_vec<5>(*params, "&")) { | |
520 | boost::string_view key, val; | |
521 | const auto parsed_pair = parse_key_value(s); | |
522 | if (parsed_pair) { | |
523 | std::tie(key, val) = *parsed_pair; | |
524 | } else { | |
525 | /* Handling a parameter without any value (even the empty one). That's | |
526 | * it, we've encountered something like "this_param&other_param=val" | |
527 | * which is used by S3 for subresources. */ | |
528 | key = s; | |
529 | } | |
530 | ||
531 | if (using_qs && key == "X-Amz-Signature") { | |
532 | /* Preserving the original behaviour of get_v4_canonical_qs() here. */ | |
533 | continue; | |
534 | } | |
535 | ||
536 | if (key == "X-Amz-Credential") { | |
537 | /* FIXME(rzarzynski): I can't find any comment in the previously linked | |
538 | * Amazon's docs saying that X-Amz-Credential should be handled in this | |
539 | * way. */ | |
540 | canonical_qs_map[key.to_string()] = val.to_string(); | |
541 | } else { | |
542 | canonical_qs_map[aws4_uri_recode(key)] = aws4_uri_recode(val); | |
543 | } | |
544 | } | |
545 | ||
546 | /* Thanks to the early exist we have the guarantee that canonical_qs_map has | |
547 | * at least one element. */ | |
548 | auto iter = std::begin(canonical_qs_map); | |
549 | std::string canonical_qs; | |
550 | canonical_qs.append(iter->first) | |
551 | .append("=", ::strlen("=")) | |
552 | .append(iter->second); | |
553 | ||
554 | for (iter++; iter != std::end(canonical_qs_map); iter++) { | |
555 | canonical_qs.append("&", ::strlen("&")) | |
556 | .append(iter->first) | |
557 | .append("=", ::strlen("=")) | |
558 | .append(iter->second); | |
559 | } | |
560 | ||
561 | return canonical_qs; | |
562 | } | |
563 | ||
564 | boost::optional<std::string> | |
565 | get_v4_canonical_headers(const req_info& info, | |
566 | const boost::string_view& signedheaders, | |
567 | const bool using_qs, | |
568 | const bool force_boto2_compat) | |
569 | { | |
570 | std::map<boost::string_view, std::string> canonical_hdrs_map; | |
571 | for (const auto& token : get_str_vec<5>(signedheaders, ";")) { | |
572 | /* TODO(rzarzynski): we'd like to switch to sstring here but it should | |
573 | * get push_back() and reserve() first. */ | |
574 | std::string token_env = "HTTP_"; | |
575 | token_env.reserve(token.length() + std::strlen("HTTP_") + 1); | |
576 | ||
577 | std::transform(std::begin(token), std::end(token), | |
578 | std::back_inserter(token_env), [](const int c) { | |
579 | return c == '-' ? '_' : std::toupper(c); | |
580 | }); | |
581 | ||
582 | if (token_env == "HTTP_CONTENT_LENGTH") { | |
583 | token_env = "CONTENT_LENGTH"; | |
584 | } else if (token_env == "HTTP_CONTENT_TYPE") { | |
585 | token_env = "CONTENT_TYPE"; | |
586 | } | |
587 | const char* const t = info.env->get(token_env.c_str()); | |
588 | if (!t) { | |
589 | dout(10) << "warning env var not available" << dendl; | |
590 | continue; | |
591 | } | |
592 | ||
593 | std::string token_value(t); | |
594 | if (token_env == "HTTP_CONTENT_MD5" && | |
595 | !std::all_of(std::begin(token_value), std::end(token_value), | |
596 | is_base64_for_content_md5)) { | |
597 | dout(0) << "NOTICE: bad content-md5 provided (not base64)" | |
598 | << ", aborting request" << dendl; | |
599 | return boost::none; | |
600 | } | |
601 | ||
602 | if (force_boto2_compat && using_qs && token == "host") { | |
603 | boost::string_view port = info.env->get("SERVER_PORT", ""); | |
604 | boost::string_view secure_port = info.env->get("SERVER_PORT_SECURE", ""); | |
605 | ||
606 | if (!secure_port.empty()) { | |
607 | if (secure_port != "443") | |
608 | token_value.append(":", std::strlen(":")) | |
609 | .append(secure_port.data(), secure_port.length()); | |
610 | } else if (!port.empty()) { | |
611 | if (port != "80") | |
612 | token_value.append(":", std::strlen(":")) | |
613 | .append(port.data(), port.length()); | |
614 | } | |
615 | } | |
616 | ||
617 | canonical_hdrs_map[token] = rgw_trim_whitespace(token_value); | |
618 | } | |
619 | ||
620 | std::string canonical_hdrs; | |
621 | for (const auto& header : canonical_hdrs_map) { | |
622 | const boost::string_view& name = header.first; | |
623 | const std::string& value = header.second; | |
624 | ||
625 | canonical_hdrs.append(name.data(), name.length()) | |
626 | .append(":", std::strlen(":")) | |
627 | .append(value) | |
628 | .append("\n", std::strlen("\n")); | |
629 | } | |
630 | ||
631 | return canonical_hdrs; | |
632 | } | |
633 | ||
634 | /* | |
635 | * create canonical request for signature version 4 | |
636 | * | |
637 | * http://docs.aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html | |
638 | */ | |
639 | sha256_digest_t | |
640 | get_v4_canon_req_hash(CephContext* cct, | |
641 | const boost::string_view& http_verb, | |
642 | const std::string& canonical_uri, | |
643 | const std::string& canonical_qs, | |
644 | const std::string& canonical_hdrs, | |
645 | const boost::string_view& signed_hdrs, | |
646 | const boost::string_view& request_payload_hash) | |
647 | { | |
648 | ldout(cct, 10) << "payload request hash = " << request_payload_hash << dendl; | |
649 | ||
650 | const auto canonical_req = string_join_reserve("\n", | |
651 | http_verb, | |
652 | canonical_uri, | |
653 | canonical_qs, | |
654 | canonical_hdrs, | |
655 | signed_hdrs, | |
656 | request_payload_hash); | |
657 | ||
658 | const auto canonical_req_hash = calc_hash_sha256(canonical_req); | |
659 | ||
660 | ldout(cct, 10) << "canonical request = " << canonical_req << dendl; | |
661 | ldout(cct, 10) << "canonical request hash = " | |
662 | << buf_to_hex(canonical_req_hash).data() << dendl; | |
663 | ||
664 | return canonical_req_hash; | |
665 | } | |
666 | ||
667 | /* | |
668 | * create string to sign for signature version 4 | |
669 | * | |
670 | * http://docs.aws.amazon.com/general/latest/gr/sigv4-create-string-to-sign.html | |
671 | */ | |
672 | AWSEngine::VersionAbstractor::string_to_sign_t | |
673 | get_v4_string_to_sign(CephContext* const cct, | |
674 | const boost::string_view& algorithm, | |
675 | const boost::string_view& request_date, | |
676 | const boost::string_view& credential_scope, | |
677 | const sha256_digest_t& canonreq_hash) | |
678 | { | |
679 | const auto hexed_cr_hash = buf_to_hex(canonreq_hash); | |
680 | const boost::string_view hexed_cr_hash_str(hexed_cr_hash.data(), | |
681 | hexed_cr_hash.size() - 1); | |
682 | ||
683 | const auto string_to_sign = string_join_reserve("\n", | |
684 | algorithm, | |
685 | request_date, | |
686 | credential_scope, | |
687 | hexed_cr_hash_str); | |
688 | ||
689 | ldout(cct, 10) << "string to sign = " | |
690 | << rgw::crypt_sanitize::log_content{string_to_sign} | |
691 | << dendl; | |
692 | ||
693 | return string_to_sign; | |
694 | } | |
695 | ||
696 | ||
697 | static inline std::tuple<boost::string_view, /* date */ | |
698 | boost::string_view, /* region */ | |
699 | boost::string_view> /* service */ | |
700 | parse_cred_scope(boost::string_view credential_scope) | |
701 | { | |
702 | /* date cred */ | |
703 | size_t pos = credential_scope.find("/"); | |
704 | const auto date_cs = credential_scope.substr(0, pos); | |
705 | credential_scope = credential_scope.substr(pos + 1); | |
706 | ||
707 | /* region cred */ | |
708 | pos = credential_scope.find("/"); | |
709 | const auto region_cs = credential_scope.substr(0, pos); | |
710 | credential_scope = credential_scope.substr(pos + 1); | |
711 | ||
712 | /* service cred */ | |
713 | pos = credential_scope.find("/"); | |
714 | const auto service_cs = credential_scope.substr(0, pos); | |
715 | ||
716 | return std::make_tuple(date_cs, region_cs, service_cs); | |
717 | } | |
718 | ||
719 | static inline std::vector<unsigned char> | |
720 | transform_secret_key(const boost::string_view& secret_access_key) | |
721 | { | |
722 | /* TODO(rzarzynski): switch to constexpr when C++14 becomes available. */ | |
723 | static const std::initializer_list<unsigned char> AWS4 { 'A', 'W', 'S', '4' }; | |
724 | ||
725 | /* boost::container::small_vector might be used here if someone wants to | |
726 | * optimize out even more dynamic allocations. */ | |
727 | std::vector<unsigned char> secret_key_utf8; | |
728 | secret_key_utf8.reserve(AWS4.size() + secret_access_key.size()); | |
729 | secret_key_utf8.assign(AWS4); | |
730 | ||
731 | for (const auto c : secret_access_key) { | |
732 | std::array<unsigned char, MAX_UTF8_SZ> buf; | |
733 | const size_t n = encode_utf8(c, buf.data()); | |
734 | secret_key_utf8.insert(std::end(secret_key_utf8), | |
735 | std::begin(buf), std::begin(buf) + n); | |
736 | } | |
737 | ||
738 | return secret_key_utf8; | |
739 | } | |
740 | ||
741 | /* | |
742 | * calculate the SigningKey of AWS auth version 4 | |
743 | */ | |
744 | static sha256_digest_t | |
745 | get_v4_signing_key(CephContext* const cct, | |
746 | const boost::string_view& credential_scope, | |
747 | const boost::string_view& secret_access_key) | |
748 | { | |
749 | boost::string_view date, region, service; | |
750 | std::tie(date, region, service) = parse_cred_scope(credential_scope); | |
751 | ||
752 | const auto utfed_sec_key = transform_secret_key(secret_access_key); | |
753 | const auto date_k = calc_hmac_sha256(utfed_sec_key, date); | |
754 | const auto region_k = calc_hmac_sha256(date_k, region); | |
755 | const auto service_k = calc_hmac_sha256(region_k, service); | |
756 | ||
757 | /* aws4_request */ | |
758 | const auto signing_key = calc_hmac_sha256(service_k, | |
759 | boost::string_view("aws4_request")); | |
760 | ||
761 | ldout(cct, 10) << "date_k = " << buf_to_hex(date_k).data() << dendl; | |
762 | ldout(cct, 10) << "region_k = " << buf_to_hex(region_k).data() << dendl; | |
763 | ldout(cct, 10) << "service_k = " << buf_to_hex(service_k).data() << dendl; | |
764 | ldout(cct, 10) << "signing_k = " << buf_to_hex(signing_key).data() << dendl; | |
765 | ||
766 | return signing_key; | |
767 | } | |
768 | ||
769 | /* | |
770 | * calculate the AWS signature version 4 | |
771 | * | |
772 | * http://docs.aws.amazon.com/general/latest/gr/sigv4-calculate-signature.html | |
773 | * | |
774 | * srv_signature_t is an alias over Ceph's basic_sstring. We're using | |
775 | * it to keep everything within the stack boundaries instead of doing | |
776 | * dynamic allocations. | |
777 | */ | |
778 | AWSEngine::VersionAbstractor::server_signature_t | |
779 | get_v4_signature(const boost::string_view& credential_scope, | |
780 | CephContext* const cct, | |
781 | const boost::string_view& secret_key, | |
782 | const AWSEngine::VersionAbstractor::string_to_sign_t& string_to_sign) | |
783 | { | |
784 | auto signing_key = get_v4_signing_key(cct, credential_scope, secret_key); | |
785 | ||
786 | /* The server-side generated digest for comparison. */ | |
787 | const auto digest = calc_hmac_sha256(signing_key, string_to_sign); | |
788 | ||
789 | /* TODO(rzarzynski): I would love to see our sstring having reserve() and | |
790 | * the non-const data() variant like C++17's std::string. */ | |
791 | using srv_signature_t = AWSEngine::VersionAbstractor::server_signature_t; | |
792 | srv_signature_t signature(srv_signature_t::initialized_later(), | |
793 | digest.size() * 2); | |
794 | buf_to_hex(digest.data(), digest.size(), signature.begin()); | |
795 | ||
796 | ldout(cct, 10) << "generated signature = " << signature << dendl; | |
797 | ||
798 | return signature; | |
799 | } | |
800 | ||
801 | AWSEngine::VersionAbstractor::server_signature_t | |
802 | get_v2_signature(CephContext* const cct, | |
803 | const std::string& secret_key, | |
804 | const AWSEngine::VersionAbstractor::string_to_sign_t& string_to_sign) | |
805 | { | |
806 | if (secret_key.empty()) { | |
807 | throw -EINVAL; | |
808 | } | |
809 | ||
810 | const auto digest = calc_hmac_sha1(secret_key, string_to_sign); | |
811 | ||
812 | /* 64 is really enough */; | |
813 | char buf[64]; | |
814 | const int ret = ceph_armor(std::begin(buf), | |
815 | std::begin(buf) + 64, | |
816 | std::begin(digest), | |
817 | std::begin(digest) + digest.size()); | |
818 | if (ret < 0) { | |
819 | ldout(cct, 10) << "ceph_armor failed" << dendl; | |
820 | throw ret; | |
821 | } else { | |
822 | buf[ret] = '\0'; | |
823 | using srv_signature_t = AWSEngine::VersionAbstractor::server_signature_t; | |
824 | return srv_signature_t(buf, ret); | |
825 | } | |
826 | } | |
827 | ||
828 | bool AWSv4ComplMulti::ChunkMeta::is_new_chunk_in_stream(size_t stream_pos) const | |
829 | { | |
830 | return stream_pos >= (data_offset_in_stream + data_length); | |
831 | } | |
832 | ||
833 | size_t AWSv4ComplMulti::ChunkMeta::get_data_size(size_t stream_pos) const | |
834 | { | |
835 | if (stream_pos > (data_offset_in_stream + data_length)) { | |
836 | /* Data in parsing_buf. */ | |
837 | return data_length; | |
838 | } else { | |
839 | return data_offset_in_stream + data_length - stream_pos; | |
840 | } | |
841 | } | |
842 | ||
843 | ||
844 | /* AWSv4 completers begin. */ | |
845 | std::pair<AWSv4ComplMulti::ChunkMeta, size_t /* consumed */> | |
846 | AWSv4ComplMulti::ChunkMeta::create_next(CephContext* const cct, | |
847 | ChunkMeta&& old, | |
848 | const char* const metabuf, | |
849 | const size_t metabuf_len) | |
850 | { | |
851 | boost::string_ref metastr(metabuf, metabuf_len); | |
852 | ||
853 | const size_t semicolon_pos = metastr.find(";"); | |
854 | if (semicolon_pos == boost::string_ref::npos) { | |
855 | ldout(cct, 20) << "AWSv4ComplMulti cannot find the ';' separator" | |
856 | << dendl; | |
857 | throw rgw::io::Exception(EINVAL, std::system_category()); | |
858 | } | |
859 | ||
860 | char* data_field_end; | |
861 | /* strtoull ignores the "\r\n" sequence after each non-first chunk. */ | |
862 | const size_t data_length = std::strtoull(metabuf, &data_field_end, 16); | |
863 | if (data_length == 0 && data_field_end == metabuf) { | |
864 | ldout(cct, 20) << "AWSv4ComplMulti: cannot parse the data size" | |
865 | << dendl; | |
866 | throw rgw::io::Exception(EINVAL, std::system_category()); | |
867 | } | |
868 | ||
869 | /* Parse the chunk_signature=... part. */ | |
870 | const auto signature_part = metastr.substr(semicolon_pos + 1); | |
871 | const size_t eq_sign_pos = signature_part.find("="); | |
872 | if (eq_sign_pos == boost::string_ref::npos) { | |
873 | ldout(cct, 20) << "AWSv4ComplMulti: cannot find the '=' separator" | |
874 | << dendl; | |
875 | throw rgw::io::Exception(EINVAL, std::system_category()); | |
876 | } | |
877 | ||
878 | /* OK, we have at least the beginning of a signature. */ | |
879 | const size_t data_sep_pos = signature_part.find("\r\n"); | |
880 | if (data_sep_pos == boost::string_ref::npos) { | |
881 | ldout(cct, 20) << "AWSv4ComplMulti: no new line at signature end" | |
882 | << dendl; | |
883 | throw rgw::io::Exception(EINVAL, std::system_category()); | |
884 | } | |
885 | ||
886 | const auto signature = \ | |
887 | signature_part.substr(eq_sign_pos + 1, data_sep_pos - 1 - eq_sign_pos); | |
888 | if (signature.length() != SIG_SIZE) { | |
889 | ldout(cct, 20) << "AWSv4ComplMulti: signature.length() != 64" | |
890 | << dendl; | |
891 | throw rgw::io::Exception(EINVAL, std::system_category()); | |
892 | } | |
893 | ||
894 | const size_t data_starts_in_stream = \ | |
895 | + semicolon_pos + strlen(";") + data_sep_pos + strlen("\r\n") | |
896 | + old.data_offset_in_stream + old.data_length; | |
897 | ||
898 | ldout(cct, 20) << "parsed new chunk; signature=" << signature | |
899 | << ", data_length=" << data_length | |
900 | << ", data_starts_in_stream=" << data_starts_in_stream | |
901 | << dendl; | |
902 | ||
903 | return std::make_pair(ChunkMeta(data_starts_in_stream, | |
904 | data_length, | |
905 | signature), | |
906 | semicolon_pos + 83); | |
907 | } | |
908 | ||
909 | std::string | |
910 | AWSv4ComplMulti::calc_chunk_signature(const std::string& payload_hash) const | |
911 | { | |
912 | const auto string_to_sign = string_join_reserve("\n", | |
913 | AWS4_HMAC_SHA256_PAYLOAD_STR, | |
914 | date, | |
915 | credential_scope, | |
916 | prev_chunk_signature, | |
917 | AWS4_EMPTY_PAYLOAD_HASH, | |
918 | payload_hash); | |
919 | ||
920 | ldout(cct, 20) << "AWSv4ComplMulti: string_to_sign=\n" << string_to_sign | |
921 | << dendl; | |
922 | ||
923 | /* new chunk signature */ | |
924 | const auto sighex = buf_to_hex(calc_hmac_sha256(signing_key, | |
925 | string_to_sign)); | |
926 | /* FIXME(rzarzynski): std::string here is really unnecessary. */ | |
927 | return std::string(sighex.data(), sighex.size() - 1); | |
928 | } | |
929 | ||
930 | ||
931 | bool AWSv4ComplMulti::is_signature_mismatched() | |
932 | { | |
933 | /* The validity of previous chunk can be verified only after getting meta- | |
934 | * data of the next one. */ | |
935 | const auto payload_hash = calc_hash_sha256_restart_stream(&sha256_hash); | |
936 | const auto calc_signature = calc_chunk_signature(payload_hash); | |
937 | ||
938 | if (chunk_meta.get_signature() != calc_signature) { | |
939 | ldout(cct, 20) << "AWSv4ComplMulti: ERROR: chunk signature mismatch" | |
940 | << dendl; | |
941 | ldout(cct, 20) << "AWSv4ComplMulti: declared signature=" | |
942 | << chunk_meta.get_signature() << dendl; | |
943 | ldout(cct, 20) << "AWSv4ComplMulti: calculated signature=" | |
944 | << calc_signature << dendl; | |
945 | ||
946 | return true; | |
947 | } else { | |
948 | prev_chunk_signature = chunk_meta.get_signature(); | |
949 | return false; | |
950 | } | |
951 | } | |
952 | ||
953 | size_t AWSv4ComplMulti::recv_body(char* const buf, const size_t buf_max) | |
954 | { | |
955 | /* Buffer stores only parsed stream. Raw values reflect the stream | |
956 | * we're getting from a client. */ | |
957 | size_t buf_pos = 0; | |
958 | ||
959 | if (chunk_meta.is_new_chunk_in_stream(stream_pos)) { | |
960 | /* Verify signature of the previous chunk. We aren't doing that for new | |
961 | * one as the procedure requires calculation of payload hash. This code | |
962 | * won't be triggered for the last, zero-length chunk. Instead, is will | |
963 | * be checked in the complete() method. */ | |
964 | if (stream_pos >= ChunkMeta::META_MAX_SIZE && is_signature_mismatched()) { | |
965 | throw rgw::io::Exception(ERR_SIGNATURE_NO_MATCH, std::system_category()); | |
966 | } | |
967 | ||
968 | /* We don't have metadata for this range. This means a new chunk, so we | |
969 | * need to parse a fresh portion of the stream. Let's start. */ | |
970 | size_t to_extract = parsing_buf.capacity() - parsing_buf.size(); | |
971 | do { | |
972 | const size_t orig_size = parsing_buf.size(); | |
973 | parsing_buf.resize(parsing_buf.size() + to_extract); | |
974 | const size_t received = io_base_t::recv_body(parsing_buf.data() + orig_size, | |
975 | to_extract); | |
976 | parsing_buf.resize(parsing_buf.size() - (to_extract - received)); | |
977 | if (received == 0) { | |
978 | break; | |
979 | } | |
980 | ||
981 | stream_pos += received; | |
982 | to_extract -= received; | |
983 | } while (to_extract > 0); | |
984 | ||
985 | size_t consumed; | |
986 | std::tie(chunk_meta, consumed) = \ | |
987 | ChunkMeta::create_next(cct, std::move(chunk_meta), | |
988 | parsing_buf.data(), parsing_buf.size()); | |
989 | ||
990 | /* We can drop the bytes consumed during metadata parsing. The remainder | |
991 | * can be chunk's data plus possibly beginning of next chunks' metadata. */ | |
992 | parsing_buf.erase(std::begin(parsing_buf), | |
993 | std::begin(parsing_buf) + consumed); | |
994 | } | |
995 | ||
996 | size_t stream_pos_was = stream_pos - parsing_buf.size(); | |
997 | ||
998 | size_t to_extract = \ | |
999 | std::min(chunk_meta.get_data_size(stream_pos_was), buf_max); | |
1000 | dout(30) << "AWSv4ComplMulti: stream_pos_was=" << stream_pos_was << ", to_extract=" << to_extract << dendl; | |
1001 | ||
1002 | /* It's quite probable we have a couple of real data bytes stored together | |
1003 | * with meta-data in the parsing_buf. We need to extract them and move to | |
1004 | * the final buffer. This is a trade-off between frontend's read overhead | |
1005 | * and memcpy. */ | |
1006 | if (to_extract > 0 && parsing_buf.size() > 0) { | |
1007 | const auto data_len = std::min(to_extract, parsing_buf.size()); | |
1008 | const auto data_end_iter = std::begin(parsing_buf) + data_len; | |
1009 | dout(30) << "AWSv4ComplMulti: to_extract=" << to_extract << ", data_len=" << data_len << dendl; | |
1010 | ||
1011 | std::copy(std::begin(parsing_buf), data_end_iter, buf); | |
1012 | parsing_buf.erase(std::begin(parsing_buf), data_end_iter); | |
1013 | ||
1014 | calc_hash_sha256_update_stream(sha256_hash, buf, data_len); | |
1015 | ||
1016 | to_extract -= data_len; | |
1017 | buf_pos += data_len; | |
1018 | } | |
1019 | ||
1020 | /* Now we can do the bulk read directly from RestfulClient without any extra | |
1021 | * buffering. */ | |
1022 | while (to_extract > 0) { | |
1023 | const size_t received = io_base_t::recv_body(buf + buf_pos, to_extract); | |
1024 | dout(30) << "AWSv4ComplMulti: to_extract=" << to_extract << ", received=" << received << dendl; | |
1025 | ||
1026 | if (received == 0) { | |
1027 | break; | |
1028 | } | |
1029 | ||
1030 | calc_hash_sha256_update_stream(sha256_hash, buf + buf_pos, received); | |
1031 | ||
1032 | buf_pos += received; | |
1033 | stream_pos += received; | |
1034 | to_extract -= received; | |
1035 | } | |
1036 | ||
1037 | dout(20) << "AWSv4ComplMulti: filled=" << buf_pos << dendl; | |
1038 | return buf_pos; | |
1039 | } | |
1040 | ||
1041 | void AWSv4ComplMulti::modify_request_state(req_state* const s_rw) | |
1042 | { | |
1043 | const char* const decoded_length = \ | |
1044 | s_rw->info.env->get("HTTP_X_AMZ_DECODED_CONTENT_LENGTH"); | |
1045 | ||
1046 | if (!decoded_length) { | |
1047 | throw -EINVAL; | |
1048 | } else { | |
1049 | s_rw->length = decoded_length; | |
1050 | s_rw->content_length = parse_content_length(decoded_length); | |
1051 | ||
1052 | if (s_rw->content_length < 0) { | |
1053 | ldout(cct, 10) << "negative AWSv4's content length, aborting" << dendl; | |
1054 | throw -EINVAL; | |
1055 | } | |
1056 | } | |
1057 | ||
1058 | /* Install the filter over rgw::io::RestfulClient. */ | |
1059 | AWS_AUTHv4_IO(s_rw)->add_filter( | |
1060 | std::static_pointer_cast<io_base_t>(shared_from_this())); | |
1061 | } | |
1062 | ||
1063 | bool AWSv4ComplMulti::complete() | |
1064 | { | |
1065 | /* Now it's time to verify the signature of the last, zero-length chunk. */ | |
1066 | if (is_signature_mismatched()) { | |
1067 | ldout(cct, 10) << "ERROR: signature of last chunk does not match" | |
1068 | << dendl; | |
1069 | return false; | |
1070 | } else { | |
1071 | return true; | |
1072 | } | |
1073 | } | |
1074 | ||
1075 | rgw::auth::Completer::cmplptr_t | |
1076 | AWSv4ComplMulti::create(const req_state* const s, | |
1077 | boost::string_view date, | |
1078 | boost::string_view credential_scope, | |
1079 | boost::string_view seed_signature, | |
1080 | const boost::optional<std::string>& secret_key) | |
1081 | { | |
1082 | if (!secret_key) { | |
1083 | /* Some external authorizers (like Keystone) aren't fully compliant with | |
1084 | * AWSv4. They do not provide the secret_key which is necessary to handle | |
1085 | * the streamed upload. */ | |
1086 | throw -ERR_NOT_IMPLEMENTED; | |
1087 | } | |
1088 | ||
1089 | const auto signing_key = \ | |
1090 | rgw::auth::s3::get_v4_signing_key(s->cct, credential_scope, *secret_key); | |
1091 | ||
1092 | return std::make_shared<AWSv4ComplMulti>(s, | |
1093 | std::move(date), | |
1094 | std::move(credential_scope), | |
1095 | std::move(seed_signature), | |
1096 | signing_key); | |
1097 | } | |
1098 | ||
1099 | size_t AWSv4ComplSingle::recv_body(char* const buf, const size_t max) | |
1100 | { | |
1101 | const auto received = io_base_t::recv_body(buf, max); | |
1102 | calc_hash_sha256_update_stream(sha256_hash, buf, received); | |
1103 | ||
1104 | return received; | |
1105 | } | |
1106 | ||
1107 | void AWSv4ComplSingle::modify_request_state(req_state* const s_rw) | |
1108 | { | |
1109 | /* Install the filter over rgw::io::RestfulClient. */ | |
1110 | AWS_AUTHv4_IO(s_rw)->add_filter( | |
1111 | std::static_pointer_cast<io_base_t>(shared_from_this())); | |
1112 | } | |
1113 | ||
1114 | bool AWSv4ComplSingle::complete() | |
1115 | { | |
1116 | /* The completer is only for the cases where signed payload has been | |
1117 | * requested. It won't be used, for instance, during the query string-based | |
1118 | * authentication. */ | |
1119 | const auto payload_hash = calc_hash_sha256_close_stream(&sha256_hash); | |
1120 | ||
1121 | /* Validate x-amz-sha256 */ | |
1122 | if (payload_hash.compare(expected_request_payload_hash) == 0) { | |
1123 | return true; | |
1124 | } else { | |
1125 | ldout(cct, 10) << "ERROR: x-amz-content-sha256 does not match" | |
1126 | << dendl; | |
1127 | ldout(cct, 10) << "ERROR: grab_aws4_sha256_hash()=" | |
1128 | << payload_hash << dendl; | |
1129 | ldout(cct, 10) << "ERROR: expected_request_payload_hash=" | |
1130 | << expected_request_payload_hash << dendl; | |
1131 | return false; | |
1132 | } | |
1133 | } | |
1134 | ||
1135 | AWSv4ComplSingle::AWSv4ComplSingle(const req_state* const s) | |
1136 | : io_base_t(nullptr), | |
1137 | cct(s->cct), | |
1138 | expected_request_payload_hash(get_v4_exp_payload_hash(s->info)), | |
1139 | sha256_hash(calc_hash_sha256_open_stream()) { | |
1140 | } | |
1141 | ||
1142 | rgw::auth::Completer::cmplptr_t | |
1143 | AWSv4ComplSingle::create(const req_state* const s, | |
1144 | const boost::optional<std::string>&) | |
1145 | { | |
1146 | return std::make_shared<AWSv4ComplSingle>(s); | |
1147 | } | |
1148 | ||
1149 | } /* namespace s3 */ | |
1150 | } /* namespace auth */ | |
1151 | } /* namespace rgw */ |