1 /* 2 * http_header - HTTP header manipulation interfaces 3 * 4 * Copyright(c) 2018 Glenn Strauss gstrauss()gluelogic.com All rights reserved 5 * License: BSD 3-clause (same as lighttpd) 6 */ 7 #include "first.h" 8 9 #include <string.h> 10 #include "sys-strings.h" 11 12 #include "http_header.h" 13 #include "base.h" 14 #include "array.h" 15 #include "buffer.h" 16 17 18 typedef struct keyvlenvalue { 19 const int16_t key; 20 const uint16_t vlen; 21 const char value[28]; 22 } keyvlenvalue; 23 24 /* Note: must be sorted by length */ 25 /* Note: must be kept in sync with http_header.h enum http_header_e */ 26 /* Note: must be kept in sync http_headers[] and http_headers_off[] */ 27 /* http_headers_off lists first offset at which string of specific len occur */ 28 static const int8_t http_headers_off[] = { 29 -1, -1, 0, 1, 4, 9, 11, 17, 21, 25, 27, -1, 30, 31, 30 37, 40, 45, 49, -1, 52, -1, -1, 53, 54, -1, 55, -1, 57 31 }; 32 static const keyvlenvalue http_headers[] = { 33 { HTTP_HEADER_TE, CONST_LEN_STR("te") } 34 ,{ HTTP_HEADER_AGE, CONST_LEN_STR("age") } 35 ,{ HTTP_HEADER_DNT, CONST_LEN_STR("dnt") } 36 ,{ HTTP_HEADER_P3P, CONST_LEN_STR("p3p") } 37 ,{ HTTP_HEADER_HOST, CONST_LEN_STR("host") } 38 ,{ HTTP_HEADER_DATE, CONST_LEN_STR("date") } 39 ,{ HTTP_HEADER_ETAG, CONST_LEN_STR("etag") } 40 ,{ HTTP_HEADER_VARY, CONST_LEN_STR("vary") } 41 ,{ HTTP_HEADER_LINK, CONST_LEN_STR("link") } 42 ,{ HTTP_HEADER_ALLOW, CONST_LEN_STR("allow") } 43 ,{ HTTP_HEADER_RANGE, CONST_LEN_STR("range") } 44 ,{ HTTP_HEADER_COOKIE, CONST_LEN_STR("cookie") } 45 ,{ HTTP_HEADER_ACCEPT, CONST_LEN_STR("accept") } 46 ,{ HTTP_HEADER_STATUS, CONST_LEN_STR("status") } 47 ,{ HTTP_HEADER_SERVER, CONST_LEN_STR("server") } 48 ,{ HTTP_HEADER_EXPECT, CONST_LEN_STR("expect") } 49 ,{ HTTP_HEADER_PRAGMA, CONST_LEN_STR("pragma") } 50 ,{ HTTP_HEADER_UPGRADE, CONST_LEN_STR("upgrade") } 51 ,{ HTTP_HEADER_REFERER, CONST_LEN_STR("referer") } 52 ,{ HTTP_HEADER_EXPIRES, CONST_LEN_STR("expires") } 53 ,{ HTTP_HEADER_ALT_SVC, CONST_LEN_STR("alt-svc") } 54 ,{ HTTP_HEADER_LOCATION, CONST_LEN_STR("location") } 55 ,{ HTTP_HEADER_IF_MATCH, CONST_LEN_STR("if-match") } 56 ,{ HTTP_HEADER_IF_RANGE, CONST_LEN_STR("if-range") } 57 ,{ HTTP_HEADER_ALT_USED, CONST_LEN_STR("alt-used") } 58 ,{ HTTP_HEADER_FORWARDED, CONST_LEN_STR("forwarded") } 59 ,{ HTTP_HEADER_EXPECT_CT, CONST_LEN_STR("expect-ct") } 60 ,{ HTTP_HEADER_CONNECTION, CONST_LEN_STR("connection") } 61 ,{ HTTP_HEADER_SET_COOKIE, CONST_LEN_STR("set-cookie") } 62 ,{ HTTP_HEADER_USER_AGENT, CONST_LEN_STR("user-agent") } 63 ,{ HTTP_HEADER_CONTENT_TYPE, CONST_LEN_STR("content-type") } 64 ,{ HTTP_HEADER_LAST_MODIFIED, CONST_LEN_STR("last-modified") } 65 ,{ HTTP_HEADER_AUTHORIZATION, CONST_LEN_STR("authorization") } 66 ,{ HTTP_HEADER_IF_NONE_MATCH, CONST_LEN_STR("if-none-match") } 67 ,{ HTTP_HEADER_CACHE_CONTROL, CONST_LEN_STR("cache-control") } 68 ,{ HTTP_HEADER_ACCEPT_RANGES, CONST_LEN_STR("accept-ranges") } 69 ,{ HTTP_HEADER_CONTENT_RANGE, CONST_LEN_STR("content-range") } 70 ,{ HTTP_HEADER_CONTENT_LENGTH, CONST_LEN_STR("content-length") } 71 ,{ HTTP_HEADER_HTTP2_SETTINGS, CONST_LEN_STR("http2-settings") } 72 ,{ HTTP_HEADER_ONION_LOCATION, CONST_LEN_STR("onion-location") } 73 ,{ HTTP_HEADER_ACCEPT_ENCODING, CONST_LEN_STR("accept-encoding") } 74 ,{ HTTP_HEADER_ACCEPT_LANGUAGE, CONST_LEN_STR("accept-language") } 75 ,{ HTTP_HEADER_REFERRER_POLICY, CONST_LEN_STR("referrer-policy") } 76 ,{ HTTP_HEADER_X_FORWARDED_FOR, CONST_LEN_STR("x-forwarded-for") } 77 ,{ HTTP_HEADER_X_FRAME_OPTIONS, CONST_LEN_STR("x-frame-options") } 78 ,{ HTTP_HEADER_WWW_AUTHENTICATE, CONST_LEN_STR("www-authenticate") } 79 ,{ HTTP_HEADER_CONTENT_ENCODING, CONST_LEN_STR("content-encoding") } 80 ,{ HTTP_HEADER_CONTENT_LOCATION, CONST_LEN_STR("content-location") } 81 ,{ HTTP_HEADER_X_XSS_PROTECTION, CONST_LEN_STR("x-xss-protection") } 82 ,{ HTTP_HEADER_IF_MODIFIED_SINCE, CONST_LEN_STR("if-modified-since") } 83 ,{ HTTP_HEADER_TRANSFER_ENCODING, CONST_LEN_STR("transfer-encoding") } 84 ,{ HTTP_HEADER_X_FORWARDED_PROTO, CONST_LEN_STR("x-forwarded-proto") } 85 ,{ HTTP_HEADER_IF_UNMODIFIED_SINCE, CONST_LEN_STR("if-unmodified-since") } 86 ,{ HTTP_HEADER_X_CONTENT_TYPE_OPTIONS, CONST_LEN_STR("x-content-type-options") } 87 ,{ HTTP_HEADER_CONTENT_SECURITY_POLICY, CONST_LEN_STR("content-security-policy") } 88 ,{ HTTP_HEADER_STRICT_TRANSPORT_SECURITY, CONST_LEN_STR("strict-transport-security") } 89 ,{ HTTP_HEADER_UPGRADE_INSECURE_REQUESTS, CONST_LEN_STR("upgrade-insecure-requests") } 90 ,{ HTTP_HEADER_ACCESS_CONTROL_ALLOW_ORIGIN, CONST_LEN_STR("access-control-allow-origin") } 91 ,{ HTTP_HEADER_OTHER, 0, "" } 92 }; 93 94 enum http_header_e http_header_hkey_get(const char * const s, const uint32_t slen) { 95 const struct keyvlenvalue * const kv = http_headers; 96 int i = slen < sizeof(http_headers_off) ? http_headers_off[slen] : -1; 97 if (i < 0) return HTTP_HEADER_OTHER; 98 do { 99 if (buffer_eq_icase_ssn(s, kv[i].value, slen)) 100 return (enum http_header_e)kv[i].key; 101 } while (slen == kv[++i].vlen); 102 return HTTP_HEADER_OTHER; 103 } 104 105 enum http_header_e http_header_hkey_get_lc(const char * const s, const uint32_t slen) { 106 const struct keyvlenvalue * const kv = http_headers; 107 int i = slen < sizeof(http_headers_off) ? http_headers_off[slen] : -1; 108 if (i < 0) return HTTP_HEADER_OTHER; 109 do { 110 if (0 == memcmp(s, kv[i].value, slen)) 111 return (enum http_header_e)kv[i].key; 112 } while (slen == kv[++i].vlen); 113 return HTTP_HEADER_OTHER; 114 } 115 116 117 int http_header_str_to_code (const char * const s) 118 { 119 /*(more strict than strtol(); exactly 3 digits followed by SP/TAB/NIL)*/ 120 return (light_isdigit(s[0]) && light_isdigit(s[1]) && light_isdigit(s[2]) 121 && (s[3] == '\0' || s[3] == ' ' || s[3] == '\t')) 122 ? (s[0]-'0')*100 + (s[1]-'0')*10 + (s[2]-'0') 123 : -1; 124 } 125 126 int http_header_str_contains_token (const char * const s, const uint32_t slen, const char * const m, const uint32_t mlen) 127 { 128 /*if (slen < mlen) return 0;*//*(possible optimizations for caller)*/ 129 /*if (slen == mlen && buffer_eq_icase_ssn(s, m, mlen)) return 1;*/ 130 /*(note: does not handle quoted-string)*/ 131 uint32_t i = 0; 132 do { 133 while (i < slen && (s[i]==' ' || s[i]=='\t' || s[i]==',')) ++i; 134 if (slen - i < mlen) return 0; 135 if (buffer_eq_icase_ssn(s+i, m, mlen)) { 136 i += mlen; 137 if (i == slen || s[i]==' ' || s[i]=='\t' || s[i]==',' || s[i]==';') 138 return 1; 139 } 140 while (i < slen && s[i]!=',') ++i; 141 } while (i < slen); 142 return 0; 143 } 144 145 146 int http_header_remove_token (buffer * const b, const char * const m, const uint32_t mlen) 147 { 148 /*(remove all instance of token from string)*/ 149 /*(note: does not handle quoted-string)*/ 150 int rc = 0; 151 for (char *s = b->ptr; s; ) { 152 while (*s == ' ' || *s == '\t' || *s == ',') ++s; 153 if (0 == strncasecmp(s, m, mlen)) { 154 s += mlen; 155 if (*s=='\0' || *s==' ' || *s=='\t' || *s==',' || *s==';') { 156 memset(s-mlen, ' ', mlen); 157 while (*s != '\0' && *s != ',') ++s; 158 rc = 1; 159 if (*s == ',') { 160 *s++ = ' '; 161 continue; 162 } 163 else { 164 for (s -= mlen; *s != ',' && s != b->ptr; --s) ; 165 buffer_string_set_length(b, (size_t)(s - b->ptr)); 166 break; 167 } 168 } 169 } 170 s = strchr(s, ','); 171 } 172 return rc; 173 } 174 175 176 static inline void http_header_token_append(buffer * const vb, const char * const v, const uint32_t vlen) { 177 if (!buffer_string_is_empty(vb)) 178 buffer_append_string_len(vb, CONST_STR_LEN(", ")); 179 buffer_append_string_len(vb, v, vlen); 180 } 181 182 __attribute_cold__ 183 static inline void http_header_token_append_cookie(buffer * const vb, const char * const v, const uint32_t vlen) { 184 /* Cookie request header must be special-cased to use ';' separator 185 * instead of ',' to combine multiple headers (if present) */ 186 if (!buffer_string_is_empty(vb)) 187 buffer_append_string_len(vb, CONST_STR_LEN("; ")); 188 buffer_append_string_len(vb, v, vlen); 189 } 190 191 __attribute_pure__ 192 static inline buffer * http_header_generic_get_ifnotempty(const array * const a, const enum http_header_e id, const char * const k, const uint32_t klen) { 193 data_string * const ds = 194 (data_string *)array_get_element_klen_ext(a, id, k, klen); 195 return ds && !buffer_string_is_empty(&ds->value) ? &ds->value : NULL; 196 } 197 198 static inline void http_header_set_key_value(array * const a, enum http_header_e id, const char * const k, const size_t klen, const char * const v, const size_t vlen) { 199 buffer_copy_string_len(array_get_buf_ptr_ext(a, id, k, klen), v, vlen); 200 } 201 202 203 buffer * http_header_response_get(const request_st * const r, enum http_header_e id, const char *k, uint32_t klen) { 204 return light_btst(r->resp_htags, id) 205 ? http_header_generic_get_ifnotempty(&r->resp_headers, id, k, klen) 206 : NULL; 207 } 208 209 void http_header_response_unset(request_st * const r, enum http_header_e id, const char *k, uint32_t klen) { 210 if (light_btst(r->resp_htags, id)) { 211 /* (do not clear bit for HTTP_HEADER_OTHER, 212 * as there might be addtl "other" headers) */ 213 if (id > HTTP_HEADER_OTHER) light_bclr(r->resp_htags, id); 214 http_header_set_key_value(&r->resp_headers,id,k,klen,CONST_STR_LEN("")); 215 } 216 } 217 218 void http_header_response_set(request_st * const r, enum http_header_e id, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 219 /* set value, including setting blank value if 0 == vlen 220 * (note: if 0 == vlen, header is still inserted with blank value, 221 * which is used to indicate a "removed" header) 222 * (do not clear bit for HTTP_HEADER_OTHER if 0 == vlen, 223 * as there might be addtl "other" headers) */ 224 (vlen) 225 ? light_bset(r->resp_htags, id) 226 : (id > HTTP_HEADER_OTHER ? light_bclr(r->resp_htags, id) : 0); 227 http_header_set_key_value(&r->resp_headers, id, k, klen, v, vlen); 228 } 229 230 void http_header_response_append(request_st * const r, enum http_header_e id, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 231 if (0 == vlen) return; 232 light_bset(r->resp_htags, id); 233 buffer * const vb = array_get_buf_ptr_ext(&r->resp_headers, id, k, klen); 234 http_header_token_append(vb, v, vlen); 235 } 236 237 __attribute_cold__ 238 static void http_header_response_insert_addtl(request_st * const r, enum http_header_e id, const char *k, uint32_t klen, buffer * const vb, uint32_t vlen) { 239 UNUSED(id); 240 buffer_append_string_len(vb, CONST_STR_LEN("\r\n")); 241 if (r->http_version >= HTTP_VERSION_2) { 242 r->resp_header_repeated = 1; 243 char * const h = buffer_string_prepare_append(vb, klen + vlen + 2); 244 for (uint32_t i = 0; i < klen; ++i) 245 h[i] = !light_isupper(k[i]) ? k[i] : (k[i] | 0x20); 246 buffer_commit(vb, klen); 247 } 248 else 249 buffer_append_string_len(vb, k, klen); 250 buffer_append_string_len(vb, CONST_STR_LEN(": ")); 251 } 252 253 void http_header_response_insert(request_st * const r, enum http_header_e id, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 254 if (0 == vlen) return; 255 light_bset(r->resp_htags, id); 256 buffer * const vb = array_get_buf_ptr_ext(&r->resp_headers, id, k, klen); 257 if (!buffer_string_is_empty(vb)) /*append repeated field-name on new line*/ 258 http_header_response_insert_addtl(r, id, k, klen, vb, vlen); 259 buffer_append_string_len(vb, v, vlen); 260 } 261 262 263 buffer * http_header_request_get(const request_st * const r, enum http_header_e id, const char *k, uint32_t klen) { 264 return light_btst(r->rqst_htags, id) 265 ? http_header_generic_get_ifnotempty(&r->rqst_headers, id, k, klen) 266 : NULL; 267 } 268 269 void http_header_request_unset(request_st * const r, enum http_header_e id, const char *k, uint32_t klen) { 270 if (light_btst(r->rqst_htags, id)) { 271 /* (do not clear bit for HTTP_HEADER_OTHER, 272 * as there might be addtl "other" headers) */ 273 if (id > HTTP_HEADER_OTHER) light_bclr(r->rqst_htags, id); 274 http_header_set_key_value(&r->rqst_headers,id,k,klen,CONST_STR_LEN("")); 275 } 276 } 277 278 void http_header_request_set(request_st * const r, enum http_header_e id, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 279 /* set value, including setting blank value if 0 == vlen 280 * (note: if 0 == vlen, header is still inserted with blank value, 281 * which is used to indicate a "removed" header) 282 * (do not clear bit for HTTP_HEADER_OTHER if 0 == vlen, 283 * as there might be addtl "other" headers) */ 284 (vlen) 285 ? light_bset(r->rqst_htags, id) 286 : (id > HTTP_HEADER_OTHER ? light_bclr(r->rqst_htags, id) : 0); 287 http_header_set_key_value(&r->rqst_headers, id, k, klen, v, vlen); 288 } 289 290 void http_header_request_append(request_st * const r, enum http_header_e id, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 291 if (0 == vlen) return; 292 light_bset(r->rqst_htags, id); 293 buffer * const vb = array_get_buf_ptr_ext(&r->rqst_headers, id, k, klen); 294 if (id != HTTP_HEADER_COOKIE) 295 http_header_token_append(vb, v, vlen); 296 else 297 http_header_token_append_cookie(vb, v, vlen); 298 } 299 300 301 buffer * http_header_env_get(const request_st * const r, const char *k, uint32_t klen) { 302 /* similar to http_header_generic_get_ifnotempty() but without id */ 303 data_string * const ds = 304 (data_string *)array_get_element_klen(&r->env, k, klen); 305 return ds && !buffer_string_is_empty(&ds->value) ? &ds->value : NULL; 306 } 307 308 void http_header_env_set(request_st * const r, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 309 array_set_key_value(&r->env, k, klen, v, vlen); 310 } 311 312 void http_header_env_append(request_st * const r, const char *k, uint32_t klen, const char *v, uint32_t vlen) { 313 /*if (0 == vlen) return;*//* skip check; permit env var w/ blank value */ 314 buffer * const vb = array_get_buf_ptr(&r->env, k, klen); 315 if (0 == vlen) return; 316 http_header_token_append(vb, v, vlen); 317 } 318 319 320 uint32_t 321 http_header_parse_hoff (const char *n, const uint32_t clen, unsigned short hoff[8192]) 322 { 323 uint32_t hlen = 0; 324 for (const char *b; (n = memchr((b = n),'\n',clen-hlen)); ++n) { 325 uint32_t x = (uint32_t)(n - b + 1); 326 hlen += x; 327 if (x <= 2 && (x == 1 || n[-1] == '\r')) { 328 hoff[hoff[0]+1] = hlen; 329 return hlen; 330 } 331 if (++hoff[0] >= /*sizeof(hoff)/sizeof(hoff[0])-1*/ 8192-1) break; 332 hoff[hoff[0]] = hlen; 333 } 334 return 0; 335 } 336