├── throughput.png ├── .gitignore ├── config ├── README.md ├── ngx_http_js_challenge.c └── LICENSE /throughput.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/bnchdan/ngx_http_js_challenge_module/master/throughput.png -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | cmake_install.cmake 2 | *.cbp 3 | CMakeFiles 4 | cmake-build-debug 5 | CMakeCache.txt 6 | *.so 7 | Makefile 8 | .idea/ 9 | CMakeLists.txt -------------------------------------------------------------------------------- /config: -------------------------------------------------------------------------------- 1 | ngx_addon_name=ngx_http_js_challenge_module 2 | 3 | if test -n "$ngx_module_link"; then 4 | ngx_module_type=HTTP 5 | ngx_module_name=ngx_http_js_challenge_module 6 | ngx_module_srcs="$ngx_addon_dir/ngx_http_js_challenge.c" 7 | . auto/module 8 | else 9 | HTTP_MODULES="$HTTP_MODULES ngx_http_js_challenge_module" 10 | NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/ngx_http_js_challenge.c" 11 | fi -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | 2 | ## ngx_http_js_challenge_module 3 | 4 | ![GitHub](https://img.shields.io/github/license/simon987/ngx_http_js_challenge_module.svg) 5 | [![CodeFactor](https://www.codefactor.io/repository/github/simon987/ngx_http_js_challenge_module/badge)](https://www.codefactor.io/repository/github/simon987/ngx_http_js_challenge_module) 6 | 7 | 8 | [Demo website](https://ngx-js-demo.simon987.net/) 9 | 10 | Simple javascript proof-of-work based access for Nginx with virtually no overhead. 11 | 12 | Easy installation: just add `load_module /path/to/ngx_http_js_challenge_module.so;` to your 13 | `nginx.conf` file and follow the [configuration instructions](#configuration). 14 | 15 |

16 | 17 |

18 | 19 | ### Configuration 20 | 21 | **Simple configuration** 22 | ```nginx 23 | server { 24 | js_challenge on; 25 | js_challenge_secret "change me!"; 26 | 27 | # ... 28 | } 29 | ``` 30 | 31 | 32 | **Advanced configuration** 33 | ```nginx 34 | server { 35 | js_challenge on; 36 | js_challenge_secret "change me!"; 37 | js_challenge_html /path/to/body.html; 38 | js_challenge_bucket_duration 3600; 39 | js_challenge_title "Verifying your browser..."; 40 | 41 | location /static { 42 | js_challenge off; 43 | alias /static_files/; 44 | } 45 | 46 | location /sensitive { 47 | js_challenge_bucket_duration 600; 48 | #... 49 | } 50 | 51 | #... 52 | } 53 | ``` 54 | 55 | * `js_challenge on|off` Toggle javascript challenges for this config block 56 | * `js_challenge_secret "secret"` Secret for generating the challenges. DEFAULT: "changeme" 57 | * `js_challenge_html "/path/to/file.html"` Path to html file to be inserted in the `` tag of the interstitial page 58 | * `js_challenge_title "title"` Will be inserted in the `` tag of the interstitial page. DEFAULT: "Verifying your browser..." 59 | * `js_challenge_bucket_duration time` Interval to prompt js challenge, in seconds. DEFAULT: 3600 60 | 61 | ### Installation 62 | 63 | 1. Add `load_module ngx_http_js_challenge_module.so;` to `/etc/nginx/nginx.conf` 64 | 1. Reload `nginx -s reload` 65 | 66 | ### Build from source 67 | 68 | These steps have to be performed on machine with compatible configuration (same nginx, glibc, openssl version etc.) 69 | 70 | 1. Install dependencies 71 | ```bash 72 | apt install libperl-dev libgeoip-dev libgd-dev libxslt1-dev libpcre3-dev 73 | ``` 74 | 2. Download nginx tarball corresponding to your current version (Check with `nginx -v`) 75 | ```bash 76 | wget https://nginx.org/download/nginx-1.16.1.tar.gz 77 | tar -xzf nginx-1.16.1.tar.gz 78 | export NGINX_PATH=$(pwd)/nginx-1.16.1/ 79 | ``` 80 | 3. Compile the module 81 | ```bash 82 | git clone https://github.com/simon987/ngx_http_js_challenge_module 83 | cd ngx_http_js_challenge_module 84 | ./build.sh 85 | ``` 86 | 4. The dynamic module can be found at `${NGINX_PATH}/objs/ngx_http_js_challenge_module.so` 87 | 88 | 89 | 90 | ### Known limitations / TODO 91 | 92 | * Users with cookies disabled will be stuck in an infinite refresh loop (TODO: redirect with a known query param, if no cookie is specified but the query arg is set, display an error page) 93 | * If nginx is behind a reverse proxy/load balancer, the same challenge will be sent to different users and/or the response cookie will be invalidated when the user is re-routed to another server. (TODO: use the x-real-ip header when available) 94 | -------------------------------------------------------------------------------- /ngx_http_js_challenge.c: -------------------------------------------------------------------------------- 1 | #include <ngx_http.h> 2 | 3 | #include <stdio.h> 4 | #include <stdint.h> 5 | #include <string.h> 6 | 7 | #define DEFAULT_SECRET "changeme" 8 | #define SHA1_MD_LEN 20 9 | #define SHA1_STR_LEN 40 10 | 11 | #define JS_SOLVER_TEMPLATE \ 12 | "<!DOCTYPE html>" \ 13 | "<html>" \ 14 | "<head>" \ 15 | "<meta charset='UTF-8'>" \ 16 | "<title>%s" \ 17 | "" \ 18 | "" \ 19 | "" \ 24 | "%s" \ 25 | "" \ 26 | "" 27 | 28 | #define DEFAULT_TITLE "Verifying your browser..." 29 | 30 | typedef struct { 31 | ngx_flag_t enabled; 32 | ngx_uint_t bucket_duration; 33 | ngx_str_t secret; 34 | ngx_str_t html_path; 35 | ngx_str_t title; 36 | char *html; 37 | } ngx_http_js_challenge_loc_conf_t; 38 | 39 | static ngx_int_t ngx_http_js_challenge(ngx_conf_t *cf); 40 | 41 | static void *ngx_http_js_challenge_create_loc_conf(ngx_conf_t *cf); 42 | 43 | static char *ngx_http_js_challenge_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child); 44 | 45 | static ngx_int_t ngx_http_js_challenge_handler(ngx_http_request_t *r); 46 | 47 | unsigned char *__sha1(const unsigned char *d, size_t n, unsigned char *md); 48 | 49 | static ngx_command_t ngx_http_js_challenge_commands[] = { 50 | 51 | { 52 | ngx_string("js_challenge"), 53 | NGX_HTTP_LOC_CONF | NGX_HTTP_LIF_CONF | NGX_HTTP_SIF_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG, 54 | ngx_conf_set_flag_slot, 55 | NGX_HTTP_LOC_CONF_OFFSET, 56 | offsetof(ngx_http_js_challenge_loc_conf_t, enabled), 57 | NULL 58 | }, 59 | { 60 | ngx_string("js_challenge_bucket_duration"), 61 | NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1, 62 | ngx_conf_set_num_slot, 63 | NGX_HTTP_LOC_CONF_OFFSET, 64 | offsetof(ngx_http_js_challenge_loc_conf_t, bucket_duration), 65 | NULL 66 | }, 67 | { 68 | ngx_string("js_challenge_secret"), 69 | NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1, 70 | ngx_conf_set_str_slot, 71 | NGX_HTTP_LOC_CONF_OFFSET, 72 | offsetof(ngx_http_js_challenge_loc_conf_t, secret), 73 | NULL 74 | }, 75 | { 76 | ngx_string("js_challenge_html"), 77 | NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1, 78 | ngx_conf_set_str_slot, 79 | NGX_HTTP_LOC_CONF_OFFSET, 80 | offsetof(ngx_http_js_challenge_loc_conf_t, html_path), 81 | NULL 82 | }, 83 | { 84 | ngx_string("js_challenge_title"), 85 | NGX_HTTP_LOC_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1, 86 | ngx_conf_set_str_slot, 87 | NGX_HTTP_LOC_CONF_OFFSET, 88 | offsetof(ngx_http_js_challenge_loc_conf_t, title), 89 | NULL 90 | }, 91 | ngx_null_command 92 | }; 93 | 94 | /* 95 | * Module context 96 | */ 97 | static ngx_http_module_t ngx_http_js_challenge_module_ctx = { 98 | NULL, /* preconfiguration */ 99 | ngx_http_js_challenge, /* postconfiguration */ 100 | 101 | NULL, 102 | NULL, 103 | 104 | NULL, 105 | NULL, 106 | 107 | ngx_http_js_challenge_create_loc_conf, 108 | ngx_http_js_challenge_merge_loc_conf 109 | }; 110 | 111 | ngx_module_t ngx_http_js_challenge_module = { 112 | NGX_MODULE_V1, 113 | &ngx_http_js_challenge_module_ctx, 114 | ngx_http_js_challenge_commands, 115 | NGX_HTTP_MODULE, 116 | NULL, 117 | NULL, 118 | NULL, 119 | NULL, 120 | NULL, 121 | NULL, 122 | NULL, 123 | NGX_MODULE_V1_PADDING 124 | }; 125 | 126 | 127 | static void *ngx_http_js_challenge_create_loc_conf(ngx_conf_t *cf) { 128 | ngx_http_js_challenge_loc_conf_t *conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_js_challenge_loc_conf_t)); 129 | if (conf == NULL) { 130 | return NGX_CONF_ERROR; 131 | } 132 | 133 | conf->secret = (ngx_str_t) {0, NULL}; 134 | conf->bucket_duration = NGX_CONF_UNSET_UINT; 135 | conf->enabled = NGX_CONF_UNSET; 136 | 137 | return conf; 138 | } 139 | 140 | 141 | static char *ngx_http_js_challenge_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) { 142 | ngx_http_js_challenge_loc_conf_t *prev = parent; 143 | ngx_http_js_challenge_loc_conf_t *conf = child; 144 | 145 | ngx_conf_merge_uint_value(conf->bucket_duration, prev->bucket_duration, 3600) 146 | ngx_conf_merge_value(conf->enabled, prev->enabled, 0) 147 | ngx_conf_merge_str_value(conf->secret, prev->secret, DEFAULT_SECRET) 148 | ngx_conf_merge_str_value(conf->html_path, prev->html_path, NULL) 149 | ngx_conf_merge_str_value(conf->title, prev->title, DEFAULT_TITLE) 150 | 151 | if (conf->bucket_duration < 1) { 152 | ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "bucket_duration must be equal or more than 1"); 153 | return NGX_CONF_ERROR; 154 | } 155 | 156 | if (conf->html_path.data == NULL) { 157 | conf->html = NULL; 158 | } else if (conf->enabled) { 159 | 160 | // Read file in memory 161 | char path[PATH_MAX]; 162 | memcpy(path, conf->html_path.data, conf->html_path.len); 163 | *(path + conf->html_path.len) = '\0'; 164 | 165 | struct stat info; 166 | stat(path, &info); 167 | 168 | int fd = open(path, O_RDONLY, 0); 169 | if (fd < 0) { 170 | ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "js_challenge_html: Could not open file '%s': %s", path, 171 | strerror(errno)); 172 | close(fd); 173 | return NGX_CONF_ERROR; 174 | } 175 | 176 | conf->html = ngx_palloc(cf->pool, info.st_size); 177 | int ret = read(fd, conf->html, info.st_size-1); 178 | *(conf->html+ret) = '\0'; 179 | close(fd); 180 | if (ret < 0) { 181 | ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "js_challenge_html: Could not read file '%s': %s", path, 182 | strerror(errno)); 183 | return NGX_CONF_ERROR; 184 | } 185 | } 186 | 187 | return NGX_CONF_OK; 188 | } 189 | 190 | 191 | __always_inline 192 | static void buf2hex(const unsigned char *buf, size_t buflen, char *hex_string) { 193 | static const char hexdig[] = "0123456789ABCDEF"; 194 | 195 | const unsigned char *p; 196 | size_t i; 197 | 198 | char *s = hex_string; 199 | for (i = 0, p = buf; i < buflen; i++, p++) { 200 | *s++ = hexdig[(*p >> 4) & 0x0f]; 201 | *s++ = hexdig[*p & 0x0f]; 202 | } 203 | } 204 | 205 | 206 | int serve_challenge(ngx_http_request_t *r, const char *challenge, const char *html, ngx_str_t title) { 207 | 208 | ngx_buf_t *b = ngx_pcalloc(r->pool, sizeof(ngx_buf_t)); 209 | ngx_chain_t out; 210 | 211 | char challenge_c_str[SHA1_STR_LEN + 1]; 212 | memcpy(challenge_c_str, challenge, SHA1_STR_LEN); 213 | *(challenge_c_str + SHA1_STR_LEN) = '\0'; 214 | 215 | char title_c_str[4096]; 216 | memcpy(title_c_str, title.data, title.len); 217 | *(title_c_str + title.len) = '\0'; 218 | 219 | unsigned char buf[32768]; 220 | static const ngx_str_t content_type = ngx_string("text/html;charset=utf-8"); 221 | 222 | if (html == NULL) { 223 | html = "

Set the js_challenge_html /path/to/body.html; directive to change this page.

"; 224 | } 225 | 226 | size_t size = snprintf((char *) buf, sizeof(buf), JS_SOLVER_TEMPLATE, title_c_str, challenge_c_str, html); 227 | 228 | out.buf = b; 229 | out.next = NULL; 230 | 231 | // TODO: is that stack buffer gonna cause problems? 232 | b->pos = buf; 233 | b->last = buf + size; 234 | b->memory = 1; 235 | b->last_buf = 1; 236 | 237 | r->headers_out.status = NGX_HTTP_SERVICE_UNAVAILABLE; 238 | r->headers_out.content_length_n = size; 239 | r->headers_out.content_type = content_type; 240 | ngx_http_send_header(r); 241 | 242 | ngx_http_output_filter(r, &out); 243 | ngx_http_finalize_request(r, 0); 244 | return NGX_DONE; 245 | } 246 | 247 | 248 | /** 249 | * @param out 40 bytes long string! 250 | */ 251 | void get_challenge_string(int32_t bucket, ngx_str_t addr, ngx_str_t secret, char *out) { 252 | char buf[4096]; 253 | unsigned char md[SHA1_MD_LEN]; 254 | 255 | char *p = (char *) &bucket; 256 | /* 257 | * Challenge= hex( SHA1( concat(bucket, addr, secret) ) ) 258 | */ 259 | memcpy(buf, p, sizeof(bucket)); 260 | memcpy((buf + sizeof(int32_t)), addr.data, addr.len); 261 | memcpy((buf + sizeof(int32_t) + addr.len), secret.data, secret.len); 262 | 263 | __sha1((unsigned char *) buf, (size_t) (sizeof(int32_t) + addr.len + secret.len), md); 264 | buf2hex(md, SHA1_MD_LEN, out); 265 | } 266 | 267 | int verify_response(ngx_str_t response, char *challenge) { 268 | 269 | /* 270 | * Response is valid if it starts by the challenge, and 271 | * its SHA1 hash contains the digits 0xB00B at the offset 272 | * of the first digit 273 | * 274 | * e.g. 275 | * challenge = "CC003677C91D53E29F7095FF90C670C69C7C46E7" 276 | * response = "CC003677C91D53E29F7095FF90C670C69C7C46E7635919" 277 | * SHA1(response) = "CCAE6E414FA62F9C2DFC2742B00B5C94A549BAE6" 278 | * ^ offset 24 279 | */ 280 | 281 | //todo also check if the response is too large 282 | if (response.len <= SHA1_STR_LEN) { 283 | return -1; 284 | } 285 | 286 | if (strncmp(challenge, (char *) response.data, SHA1_STR_LEN) != 0) { 287 | return -1; 288 | } 289 | 290 | unsigned char md[SHA1_MD_LEN]; 291 | __sha1((unsigned char *) response.data, response.len, md); 292 | 293 | unsigned int nibble1; 294 | if (challenge[0] <= '9') { 295 | nibble1 = challenge[0] - '0'; 296 | } else { 297 | nibble1 = challenge[0] - 'A' + 10; 298 | } 299 | 300 | return md[nibble1] == 0xB0 && md[nibble1 + 1] == 0x0B ? 0 : -1; 301 | } 302 | 303 | int get_cookie(ngx_http_request_t *r, ngx_str_t *name, ngx_str_t *value) { 304 | #if defined(nginx_version) && nginx_version >= 1023000 305 | ngx_table_elt_t *h; 306 | for (h = r->headers_in.cookie; h; h = h->next) { 307 | u_char *start = h->value.data; 308 | u_char *end = h->value.data + h->value.len; 309 | #else 310 | ngx_table_elt_t **h; 311 | h = r->headers_in.cookies.elts; 312 | 313 | ngx_uint_t i = 0; 314 | for (i = 0; i < r->headers_in.cookies.nelts; i++) { 315 | u_char *start = h[i]->value.data; 316 | u_char *end = h[i]->value.data + h[i]->value.len; 317 | #endif 318 | while (start < end) { 319 | while (start < end && *start == ' ') { start++; } 320 | 321 | if (ngx_strncmp(start, name->data, name->len) == 0) { 322 | u_char *last; 323 | for (last = start; last < end && *last != ';'; last++) {} 324 | while (*start++ != '=' && start < last) {} 325 | 326 | value->data = start; 327 | value->len = (last - start); 328 | return 0; 329 | } 330 | while (*start++ != ';' && start < end) {} 331 | } 332 | } 333 | 334 | return -1; 335 | } 336 | 337 | static ngx_int_t ngx_http_js_challenge_handler(ngx_http_request_t *r) { 338 | 339 | ngx_http_js_challenge_loc_conf_t *conf = ngx_http_get_module_loc_conf(r, ngx_http_js_challenge_module); 340 | 341 | if (!conf->enabled) { 342 | return NGX_DECLINED; 343 | } 344 | 345 | unsigned long bucket = r->start_sec - (r->start_sec % conf->bucket_duration); 346 | ngx_str_t addr = r->connection->addr_text; 347 | 348 | char challenge[SHA1_STR_LEN]; 349 | get_challenge_string(bucket, addr, conf->secret, challenge); 350 | 351 | ngx_str_t response; 352 | ngx_str_t cookie_name = ngx_string("res"); 353 | int ret = get_cookie(r, &cookie_name, &response); 354 | 355 | if (ret < 0) { 356 | ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "[ js challenge log ] sending challenge... "); 357 | return serve_challenge(r, challenge, conf->html, conf->title); 358 | } 359 | 360 | get_challenge_string(bucket, addr, conf->secret, challenge); 361 | 362 | if (verify_response(response, challenge) != 0) { 363 | ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "[ js challenge log ] wrong/expired cookie (res=%s), sending challenge...", response.data); 364 | return serve_challenge(r, challenge, conf->html, conf->title); 365 | } 366 | 367 | // Fallthrough next handler 368 | return NGX_DECLINED; 369 | } 370 | 371 | /** 372 | * post configuration 373 | */ 374 | static ngx_int_t ngx_http_js_challenge(ngx_conf_t *cf) { 375 | 376 | ngx_http_handler_pt *h; 377 | ngx_http_core_main_conf_t *main_conf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module); 378 | 379 | h = ngx_array_push(&main_conf->phases[NGX_HTTP_PRECONTENT_PHASE].handlers); 380 | if (h == NULL) { 381 | ngx_log_error(NGX_LOG_ERR, cf->log, 0, "null"); 382 | return NGX_ERROR; 383 | } 384 | 385 | *h = ngx_http_js_challenge_handler; 386 | 387 | return NGX_OK; 388 | } 389 | 390 | /** 391 | * By Steve Reid 392 | * 100% Public Domain 393 | */ 394 | void __SHA1_Transform(uint32_t state[5], const uint8_t buffer[64]); 395 | 396 | #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits)))) 397 | 398 | #if defined (BYTE_ORDER) && defined(BIG_ENDIAN) && (BYTE_ORDER == BIG_ENDIAN) 399 | #define WORDS_BIGENDIAN 1 400 | #endif 401 | #ifdef _BIG_ENDIAN 402 | #define WORDS_BIGENDIAN 1 403 | #endif 404 | 405 | 406 | /* blk0() and blk() perform the initial expand. */ 407 | /* I got the idea of expanding during the round function from SSLeay */ 408 | /* FIXME: can we do this in an endian-proof way? */ 409 | #ifdef WORDS_BIGENDIAN 410 | #define blk0(i) block->l[i] 411 | #else 412 | #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xff00ff00) \ 413 | |(rol(block->l[i],8)&0x00ff00ff)) 414 | #endif 415 | #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \ 416 | ^block->l[(i+2)&15]^block->l[i&15],1)) 417 | 418 | /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */ 419 | #define R0(v, w, x, y, z, i) \ 420 | z+=((w&(x^y))^y)+blk0(i)+0x5a827999+rol(v,5);w=rol(w,30); 421 | #define R1(v, w, x, y, z, i) \ 422 | z+=((w&(x^y))^y)+blk(i)+0x5a827999+rol(v,5);w=rol(w,30); 423 | #define R2(v, w, x, y, z, i) \ 424 | z+=(w^x^y)+blk(i)+0x6ed9eba1+rol(v,5);w=rol(w,30); 425 | #define R3(v, w, x, y, z, i) \ 426 | z+=(((w|x)&y)|(w&x))+blk(i)+0x8f1bbcdc+rol(v,5);w=rol(w,30); 427 | #define R4(v, w, x, y, z, i) \ 428 | z+=(w^x^y)+blk(i)+0xca62c1d6+rol(v,5);w=rol(w,30); 429 | 430 | 431 | /* Hash a single 512-bit block. This is the core of the algorithm. */ 432 | void __SHA1_Transform(uint32_t state[5], const uint8_t buffer[64]) { 433 | uint32_t a, b, c, d, e; 434 | typedef union { 435 | uint8_t c[64]; 436 | uint32_t l[16]; 437 | } CHAR64LONG16; 438 | CHAR64LONG16 *block; 439 | 440 | CHAR64LONG16 workspace; 441 | block = &workspace; 442 | memcpy(block, buffer, 64); 443 | 444 | /* Copy context->state[] to working vars */ 445 | a = state[0]; 446 | b = state[1]; 447 | c = state[2]; 448 | d = state[3]; 449 | e = state[4]; 450 | 451 | /* 4 rounds of 20 operations each. Loop unrolled. */ 452 | R0(a, b, c, d, e, 0); 453 | R0(e, a, b, c, d, 1); 454 | R0(d, e, a, b, c, 2); 455 | R0(c, d, e, a, b, 3); 456 | R0(b, c, d, e, a, 4); 457 | R0(a, b, c, d, e, 5); 458 | R0(e, a, b, c, d, 6); 459 | R0(d, e, a, b, c, 7); 460 | R0(c, d, e, a, b, 8); 461 | R0(b, c, d, e, a, 9); 462 | R0(a, b, c, d, e, 10); 463 | R0(e, a, b, c, d, 11); 464 | R0(d, e, a, b, c, 12); 465 | R0(c, d, e, a, b, 13); 466 | R0(b, c, d, e, a, 14); 467 | R0(a, b, c, d, e, 15); 468 | R1(e, a, b, c, d, 16); 469 | R1(d, e, a, b, c, 17); 470 | R1(c, d, e, a, b, 18); 471 | R1(b, c, d, e, a, 19); 472 | R2(a, b, c, d, e, 20); 473 | R2(e, a, b, c, d, 21); 474 | R2(d, e, a, b, c, 22); 475 | R2(c, d, e, a, b, 23); 476 | R2(b, c, d, e, a, 24); 477 | R2(a, b, c, d, e, 25); 478 | R2(e, a, b, c, d, 26); 479 | R2(d, e, a, b, c, 27); 480 | R2(c, d, e, a, b, 28); 481 | R2(b, c, d, e, a, 29); 482 | R2(a, b, c, d, e, 30); 483 | R2(e, a, b, c, d, 31); 484 | R2(d, e, a, b, c, 32); 485 | R2(c, d, e, a, b, 33); 486 | R2(b, c, d, e, a, 34); 487 | R2(a, b, c, d, e, 35); 488 | R2(e, a, b, c, d, 36); 489 | R2(d, e, a, b, c, 37); 490 | R2(c, d, e, a, b, 38); 491 | R2(b, c, d, e, a, 39); 492 | R3(a, b, c, d, e, 40); 493 | R3(e, a, b, c, d, 41); 494 | R3(d, e, a, b, c, 42); 495 | R3(c, d, e, a, b, 43); 496 | R3(b, c, d, e, a, 44); 497 | R3(a, b, c, d, e, 45); 498 | R3(e, a, b, c, d, 46); 499 | R3(d, e, a, b, c, 47); 500 | R3(c, d, e, a, b, 48); 501 | R3(b, c, d, e, a, 49); 502 | R3(a, b, c, d, e, 50); 503 | R3(e, a, b, c, d, 51); 504 | R3(d, e, a, b, c, 52); 505 | R3(c, d, e, a, b, 53); 506 | R3(b, c, d, e, a, 54); 507 | R3(a, b, c, d, e, 55); 508 | R3(e, a, b, c, d, 56); 509 | R3(d, e, a, b, c, 57); 510 | R3(c, d, e, a, b, 58); 511 | R3(b, c, d, e, a, 59); 512 | R4(a, b, c, d, e, 60); 513 | R4(e, a, b, c, d, 61); 514 | R4(d, e, a, b, c, 62); 515 | R4(c, d, e, a, b, 63); 516 | R4(b, c, d, e, a, 64); 517 | R4(a, b, c, d, e, 65); 518 | R4(e, a, b, c, d, 66); 519 | R4(d, e, a, b, c, 67); 520 | R4(c, d, e, a, b, 68); 521 | R4(b, c, d, e, a, 69); 522 | R4(a, b, c, d, e, 70); 523 | R4(e, a, b, c, d, 71); 524 | R4(d, e, a, b, c, 72); 525 | R4(c, d, e, a, b, 73); 526 | R4(b, c, d, e, a, 74); 527 | R4(a, b, c, d, e, 75); 528 | R4(e, a, b, c, d, 76); 529 | R4(d, e, a, b, c, 77); 530 | R4(c, d, e, a, b, 78); 531 | R4(b, c, d, e, a, 79); 532 | 533 | /* Add the working vars back into context.state[] */ 534 | state[0] += a; 535 | state[1] += b; 536 | state[2] += c; 537 | state[3] += d; 538 | state[4] += e; 539 | 540 | /* Wipe variables */ 541 | a = b = c = d = e = 0; 542 | } 543 | 544 | typedef struct { 545 | uint32_t state[5]; 546 | uint32_t count[2]; 547 | uint8_t buffer[64]; 548 | } __SHA1_CTX; 549 | 550 | void __SHA1_Update(__SHA1_CTX *context, const void *p, size_t len); 551 | 552 | void __SHA1_Final(uint8_t digest[SHA1_MD_LEN], __SHA1_CTX *context); 553 | 554 | void __SHA1_Init(__SHA1_CTX *c) 555 | { 556 | memset(c, 0, sizeof(*c)); 557 | c->state[0] = 0x67452301UL; 558 | c->state[1] = 0xefcdab89UL; 559 | c->state[2] = 0x98badcfeUL; 560 | c->state[3] = 0x10325476UL; 561 | c->state[4] = 0xc3d2e1f0UL; 562 | } 563 | /** 564 | * Run your data through this 565 | * 566 | * @param context SHA1-Context 567 | * @param p Buffer to run SHA1 on 568 | * @param len Number of bytes 569 | */ 570 | void __SHA1_Update(__SHA1_CTX *context, const void *p, size_t len) { 571 | const uint8_t *data = p; 572 | size_t i, j; 573 | 574 | j = (context->count[0] >> 3) & 63; 575 | if ((context->count[0] += (uint32_t) (len << 3)) < (len << 3)) { 576 | context->count[1]++; 577 | } 578 | context->count[1] += (uint32_t) (len >> 29); 579 | if ((j + len) > 63) { 580 | memcpy(&context->buffer[j], data, (i = 64 - j)); 581 | __SHA1_Transform(context->state, context->buffer); 582 | for (; i + 63 < len; i += 64) { 583 | __SHA1_Transform(context->state, data + i); 584 | } 585 | j = 0; 586 | } else i = 0; 587 | memcpy(&context->buffer[j], &data[i], len - i); 588 | } 589 | 590 | 591 | /** 592 | * Add padding and return the message digest 593 | * 594 | * @param digest Generated message digest 595 | * @param context SHA1-Context 596 | */ 597 | void __SHA1_Final(uint8_t digest[SHA1_MD_LEN], __SHA1_CTX *context) { 598 | uint32_t i; 599 | uint8_t finalcount[8]; 600 | 601 | for (i = 0; i < 8; i++) { 602 | finalcount[i] = (uint8_t) ((context->count[(i >= 4 ? 0 : 1)] 603 | >> ((3 - (i & 3)) * 8)) & 255); 604 | } 605 | __SHA1_Update(context, (uint8_t *) "\200", 1); 606 | while ((context->count[0] & 504) != 448) { 607 | __SHA1_Update(context, (uint8_t *) "\0", 1); 608 | } 609 | __SHA1_Update(context, finalcount, 8); /* Should cause SHA1_Transform */ 610 | for (i = 0; i < SHA1_MD_LEN; i++) { 611 | digest[i] = (uint8_t) 612 | ((context->state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255); 613 | } 614 | 615 | /* Wipe variables */ 616 | i = 0; 617 | memset(context->buffer, 0, 64); 618 | memset(context->state, 0, 20); 619 | memset(context->count, 0, 8); 620 | memset(finalcount, 0, 8); /* SWR */ 621 | 622 | __SHA1_Transform(context->state, context->buffer); 623 | } 624 | 625 | unsigned char *__sha1(const unsigned char *d, size_t n, unsigned char *md) { 626 | __SHA1_CTX c; 627 | __SHA1_Init(&c); 628 | __SHA1_Update(&c, d, n); 629 | __SHA1_Final(md, &c); 630 | return md; 631 | } 632 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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No Surrender of Others' Freedom. 541 | 542 | If conditions are imposed on you (whether by court order, agreement or 543 | otherwise) that contradict the conditions of this License, they do not 544 | excuse you from the conditions of this License. If you cannot convey a 545 | covered work so as to satisfy simultaneously your obligations under this 546 | License and any other pertinent obligations, then as a consequence you may 547 | not convey it at all. For example, if you agree to terms that obligate you 548 | to collect a royalty for further conveying from those to whom you convey 549 | the Program, the only way you could satisfy both those terms and this 550 | License would be to refrain entirely from conveying the Program. 551 | 552 | 13. Use with the GNU Affero General Public License. 553 | 554 | Notwithstanding any other provision of this License, you have 555 | permission to link or combine any covered work with a work licensed 556 | under version 3 of the GNU Affero General Public License into a single 557 | combined work, and to convey the resulting work. The terms of this 558 | License will continue to apply to the part which is the covered work, 559 | but the special requirements of the GNU Affero General Public License, 560 | section 13, concerning interaction through a network will apply to the 561 | combination as such. 562 | 563 | 14. Revised Versions of this License. 564 | 565 | The Free Software Foundation may publish revised and/or new versions of 566 | the GNU General Public License from time to time. Such new versions will 567 | be similar in spirit to the present version, but may differ in detail to 568 | address new problems or concerns. 569 | 570 | Each version is given a distinguishing version number. If the 571 | Program specifies that a certain numbered version of the GNU General 572 | Public License "or any later version" applies to it, you have the 573 | option of following the terms and conditions either of that numbered 574 | version or of any later version published by the Free Software 575 | Foundation. If the Program does not specify a version number of the 576 | GNU General Public License, you may choose any version ever published 577 | by the Free Software Foundation. 578 | 579 | If the Program specifies that a proxy can decide which future 580 | versions of the GNU General Public License can be used, that proxy's 581 | public statement of acceptance of a version permanently authorizes you 582 | to choose that version for the Program. 583 | 584 | Later license versions may give you additional or different 585 | permissions. However, no additional obligations are imposed on any 586 | author or copyright holder as a result of your choosing to follow a 587 | later version. 588 | 589 | 15. Disclaimer of Warranty. 590 | 591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT 593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY 594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, 595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM 597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF 598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 599 | 600 | 16. Limitation of Liability. 601 | 602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS 604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY 605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE 606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF 607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD 608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), 609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF 610 | SUCH DAMAGES. 611 | 612 | 17. Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | --------------------------------------------------------------------------------