Eric Salama | 8a9c6c2 | 2017-11-10 11:02:23 +0100 | [diff] [blame] | 1 | #ifndef _SPOP_FUNCTIONS_H |
| 2 | #define _SPOP_FUNCTIONS_H |
| 3 | |
| 4 | #include <stdint.h> |
| 5 | #include <string.h> |
| 6 | #include <spoe_types.h> |
| 7 | #include <mini-sample.h> |
| 8 | |
| 9 | |
| 10 | #ifndef MIN |
| 11 | #define MIN(a, b) (((a) < (b)) ? (a) : (b)) |
| 12 | #endif |
| 13 | |
| 14 | #ifndef MAX |
| 15 | #define MAX(a, b) (((a) > (b)) ? (a) : (b)) |
| 16 | #endif |
| 17 | |
| 18 | |
| 19 | /* Encode the integer <i> into a varint (variable-length integer). The encoded |
| 20 | * value is copied in <*buf>. Here is the encoding format: |
| 21 | * |
| 22 | * 0 <= X < 240 : 1 byte (7.875 bits) [ XXXX XXXX ] |
| 23 | * 240 <= X < 2288 : 2 bytes (11 bits) [ 1111 XXXX ] [ 0XXX XXXX ] |
| 24 | * 2288 <= X < 264432 : 3 bytes (18 bits) [ 1111 XXXX ] [ 1XXX XXXX ] [ 0XXX XXXX ] |
| 25 | * 264432 <= X < 33818864 : 4 bytes (25 bits) [ 1111 XXXX ] [ 1XXX XXXX ]*2 [ 0XXX XXXX ] |
| 26 | * 33818864 <= X < 4328786160 : 5 bytes (32 bits) [ 1111 XXXX ] [ 1XXX XXXX ]*3 [ 0XXX XXXX ] |
| 27 | * ... |
| 28 | * |
| 29 | * On success, it returns the number of written bytes and <*buf> is moved after |
| 30 | * the encoded value. Otherwise, it returns -1. */ |
| 31 | static inline int |
| 32 | encode_varint(uint64_t i, char **buf, char *end) |
| 33 | { |
| 34 | unsigned char *p = (unsigned char *)*buf; |
| 35 | int r; |
| 36 | |
| 37 | if (p >= (unsigned char *)end) |
| 38 | return -1; |
| 39 | |
| 40 | if (i < 240) { |
| 41 | *p++ = i; |
| 42 | *buf = (char *)p; |
| 43 | return 1; |
| 44 | } |
| 45 | |
| 46 | *p++ = (unsigned char)i | 240; |
| 47 | i = (i - 240) >> 4; |
| 48 | while (i >= 128) { |
| 49 | if (p >= (unsigned char *)end) |
| 50 | return -1; |
| 51 | *p++ = (unsigned char)i | 128; |
| 52 | i = (i - 128) >> 7; |
| 53 | } |
| 54 | |
| 55 | if (p >= (unsigned char *)end) |
| 56 | return -1; |
| 57 | *p++ = (unsigned char)i; |
| 58 | |
| 59 | r = ((char *)p - *buf); |
| 60 | *buf = (char *)p; |
| 61 | return r; |
| 62 | } |
| 63 | |
| 64 | /* Decode a varint from <*buf> and save the decoded value in <*i>. See |
| 65 | * 'spoe_encode_varint' for details about varint. |
| 66 | * On success, it returns the number of read bytes and <*buf> is moved after the |
| 67 | * varint. Otherwise, it returns -1. */ |
| 68 | static inline int |
| 69 | decode_varint(char **buf, char *end, uint64_t *i) |
| 70 | { |
| 71 | unsigned char *p = (unsigned char *)*buf; |
| 72 | int r; |
| 73 | |
| 74 | if (p >= (unsigned char *)end) |
| 75 | return -1; |
| 76 | |
| 77 | *i = *p++; |
| 78 | if (*i < 240) { |
| 79 | *buf = (char *)p; |
| 80 | return 1; |
| 81 | } |
| 82 | |
| 83 | r = 4; |
| 84 | do { |
| 85 | if (p >= (unsigned char *)end) |
| 86 | return -1; |
| 87 | *i += (uint64_t)*p << r; |
| 88 | r += 7; |
| 89 | } while (*p++ >= 128); |
| 90 | |
| 91 | r = ((char *)p - *buf); |
| 92 | *buf = (char *)p; |
| 93 | return r; |
| 94 | } |
| 95 | |
| 96 | /* Encode a buffer. Its length <len> is encoded as a varint, followed by a copy |
| 97 | * of <str>. It must have enough space in <*buf> to encode the buffer, else an |
| 98 | * error is triggered. |
| 99 | * On success, it returns <len> and <*buf> is moved after the encoded value. If |
| 100 | * an error occurred, it returns -1. */ |
| 101 | static inline int |
| 102 | spoe_encode_buffer(const char *str, size_t len, char **buf, char *end) |
| 103 | { |
| 104 | char *p = *buf; |
| 105 | int ret; |
| 106 | |
| 107 | if (p >= end) |
| 108 | return -1; |
| 109 | |
| 110 | if (!len) { |
| 111 | *p++ = 0; |
| 112 | *buf = p; |
| 113 | return 0; |
| 114 | } |
| 115 | |
| 116 | ret = encode_varint(len, &p, end); |
| 117 | if (ret == -1 || p + len > end) |
| 118 | return -1; |
| 119 | |
| 120 | memcpy(p, str, len); |
| 121 | *buf = p + len; |
| 122 | return len; |
| 123 | } |
| 124 | |
| 125 | /* Encode a buffer, possibly partially. It does the same thing than |
| 126 | * 'spoe_encode_buffer', but if there is not enough space, it does not fail. |
| 127 | * On success, it returns the number of copied bytes and <*buf> is moved after |
| 128 | * the encoded value. If an error occured, it returns -1. */ |
| 129 | static inline int |
| 130 | spoe_encode_frag_buffer(const char *str, size_t len, char **buf, char *end) |
| 131 | { |
| 132 | char *p = *buf; |
| 133 | int ret; |
| 134 | |
| 135 | if (p >= end) |
| 136 | return -1; |
| 137 | |
| 138 | if (!len) { |
| 139 | *p++ = 0; |
| 140 | *buf = p; |
| 141 | return 0; |
| 142 | } |
| 143 | |
| 144 | ret = encode_varint(len, &p, end); |
| 145 | if (ret == -1 || p >= end) |
| 146 | return -1; |
| 147 | |
| 148 | ret = (p+len < end) ? len : (end - p); |
| 149 | memcpy(p, str, ret); |
| 150 | *buf = p + ret; |
| 151 | return ret; |
| 152 | } |
| 153 | |
| 154 | /* Decode a buffer. The buffer length is decoded and saved in <*len>. <*str> |
| 155 | * points on the first byte of the buffer. |
| 156 | * On success, it returns the buffer length and <*buf> is moved after the |
| 157 | * encoded buffer. Otherwise, it returns -1. */ |
| 158 | static inline int |
| 159 | spoe_decode_buffer(char **buf, char *end, char **str, uint64_t *len) |
| 160 | { |
| 161 | char *p = *buf; |
| 162 | uint64_t sz; |
| 163 | int ret; |
| 164 | |
| 165 | *str = NULL; |
| 166 | *len = 0; |
| 167 | |
| 168 | ret = decode_varint(&p, end, &sz); |
| 169 | if (ret == -1 || p + sz > end) |
| 170 | return -1; |
| 171 | |
| 172 | *str = p; |
| 173 | *len = sz; |
| 174 | *buf = p + sz; |
| 175 | return sz; |
| 176 | } |
| 177 | |
| 178 | /* Encode a typed data using value in <smp>. On success, it returns the number |
| 179 | * of copied bytes and <*buf> is moved after the encoded value. If an error |
| 180 | * occured, it returns -1. |
| 181 | * |
| 182 | * If the value is too big to be encoded, depending on its type, then encoding |
| 183 | * failed or the value is partially encoded. Only strings and binaries can be |
| 184 | * partially encoded. In this case, the offset <*off> is updated to known how |
| 185 | * many bytes has been encoded. If <*off> is zero at the end, it means that all |
| 186 | * data has been encoded. */ |
| 187 | static inline int |
| 188 | spoe_encode_data(struct sample *smp, unsigned int *off, char **buf, char *end) |
| 189 | { |
| 190 | char *p = *buf; |
| 191 | int ret; |
| 192 | |
| 193 | if (p >= end) |
| 194 | return -1; |
| 195 | |
| 196 | if (smp == NULL) { |
| 197 | *p++ = SPOE_DATA_T_NULL; |
| 198 | goto end; |
| 199 | } |
| 200 | |
| 201 | switch (smp->data.type) { |
| 202 | case SMP_T_BOOL: |
| 203 | *p = SPOE_DATA_T_BOOL; |
| 204 | *p++ |= ((!smp->data.u.sint) ? SPOE_DATA_FL_FALSE : SPOE_DATA_FL_TRUE); |
| 205 | break; |
| 206 | |
| 207 | case SMP_T_SINT: |
| 208 | *p++ = SPOE_DATA_T_INT64; |
| 209 | if (encode_varint(smp->data.u.sint, &p, end) == -1) |
| 210 | return -1; |
| 211 | break; |
| 212 | |
| 213 | case SMP_T_IPV4: |
| 214 | if (p + 5 > end) |
| 215 | return -1; |
| 216 | *p++ = SPOE_DATA_T_IPV4; |
| 217 | memcpy(p, &smp->data.u.ipv4, 4); |
| 218 | p += 4; |
| 219 | break; |
| 220 | |
| 221 | case SMP_T_IPV6: |
| 222 | if (p + 17 > end) |
| 223 | return -1; |
| 224 | *p++ = SPOE_DATA_T_IPV6; |
| 225 | memcpy(p, &smp->data.u.ipv6, 16); |
| 226 | p += 16; |
| 227 | break; |
| 228 | |
| 229 | case SMP_T_STR: |
| 230 | case SMP_T_BIN: { |
| 231 | struct chunk *chk = &smp->data.u.str; |
| 232 | |
| 233 | /* Here, we need to know if the sample has already been |
| 234 | * partially encoded. If yes, we only need to encode the |
| 235 | * remaining, <*off> reprensenting the number of bytes |
| 236 | * already encoded. */ |
| 237 | if (!*off) { |
| 238 | /* First evaluation of the sample : encode the |
| 239 | * type (string or binary), the buffer length |
| 240 | * (as a varint) and at least 1 byte of the |
| 241 | * buffer. */ |
| 242 | struct chunk *chk = &smp->data.u.str; |
| 243 | |
| 244 | *p++ = (smp->data.type == SMP_T_STR) |
| 245 | ? SPOE_DATA_T_STR |
| 246 | : SPOE_DATA_T_BIN; |
| 247 | ret = spoe_encode_frag_buffer(chk->str, chk->len, &p, end); |
| 248 | if (ret == -1) |
| 249 | return -1; |
| 250 | } |
| 251 | else { |
| 252 | /* The sample has been fragmented, encode remaining data */ |
| 253 | ret = MIN(chk->len - *off, end - p); |
| 254 | memcpy(p, chk->str + *off, ret); |
| 255 | p += ret; |
| 256 | } |
| 257 | /* Now update <*off> */ |
| 258 | if (ret + *off != chk->len) |
| 259 | *off += ret; |
| 260 | else |
| 261 | *off = 0; |
| 262 | break; |
| 263 | } |
| 264 | /* |
| 265 | case SMP_T_METH: { |
| 266 | char *m; |
| 267 | size_t len; |
| 268 | |
| 269 | *p++ = SPOE_DATA_T_STR; |
| 270 | switch (smp->data.u.meth.meth) { |
| 271 | case HTTP_METH_OPTIONS: m = "OPTIONS"; len = 7; break; |
| 272 | case HTTP_METH_GET : m = "GET"; len = 3; break; |
| 273 | case HTTP_METH_HEAD : m = "HEAD"; len = 4; break; |
| 274 | case HTTP_METH_POST : m = "POST"; len = 4; break; |
| 275 | case HTTP_METH_PUT : m = "PUT"; len = 3; break; |
| 276 | case HTTP_METH_DELETE : m = "DELETE"; len = 6; break; |
| 277 | case HTTP_METH_TRACE : m = "TRACE"; len = 5; break; |
| 278 | case HTTP_METH_CONNECT: m = "CONNECT"; len = 7; break; |
| 279 | |
| 280 | default : |
| 281 | m = smp->data.u.meth.str.str; |
| 282 | len = smp->data.u.meth.str.len; |
| 283 | } |
| 284 | if (spoe_encode_buffer(m, len, &p, end) == -1) |
| 285 | return -1; |
| 286 | break; |
| 287 | } |
| 288 | */ |
| 289 | |
| 290 | default: |
| 291 | *p++ = SPOE_DATA_T_NULL; |
| 292 | break; |
| 293 | } |
| 294 | |
| 295 | end: |
| 296 | ret = (p - *buf); |
| 297 | *buf = p; |
| 298 | return ret; |
| 299 | } |
| 300 | |
| 301 | /* Skip a typed data. If an error occurred, -1 is returned, otherwise the number |
| 302 | * of skipped bytes is returned and the <*buf> is moved after skipped data. |
| 303 | * |
| 304 | * A types data is composed of a type (1 byte) and corresponding data: |
| 305 | * - boolean: non additional data (0 bytes) |
| 306 | * - integers: a variable-length integer (see decode_varint) |
| 307 | * - ipv4: 4 bytes |
| 308 | * - ipv6: 16 bytes |
| 309 | * - binary and string: a buffer prefixed by its size, a variable-length |
| 310 | * integer (see spoe_decode_buffer) */ |
| 311 | static inline int |
| 312 | spoe_skip_data(char **buf, char *end) |
| 313 | { |
| 314 | char *str, *p = *buf; |
| 315 | int type, ret; |
| 316 | uint64_t v, sz; |
| 317 | |
| 318 | if (p >= end) |
| 319 | return -1; |
| 320 | |
| 321 | type = *p++; |
| 322 | switch (type & SPOE_DATA_T_MASK) { |
| 323 | case SPOE_DATA_T_BOOL: |
| 324 | break; |
| 325 | case SPOE_DATA_T_INT32: |
| 326 | case SPOE_DATA_T_INT64: |
| 327 | case SPOE_DATA_T_UINT32: |
| 328 | case SPOE_DATA_T_UINT64: |
| 329 | if (decode_varint(&p, end, &v) == -1) |
| 330 | return -1; |
| 331 | break; |
| 332 | case SPOE_DATA_T_IPV4: |
| 333 | if (p+4 > end) |
| 334 | return -1; |
| 335 | p += 4; |
| 336 | break; |
| 337 | case SPOE_DATA_T_IPV6: |
| 338 | if (p+16 > end) |
| 339 | return -1; |
| 340 | p += 16; |
| 341 | break; |
| 342 | case SPOE_DATA_T_STR: |
| 343 | case SPOE_DATA_T_BIN: |
| 344 | /* All the buffer must be skipped */ |
| 345 | if (spoe_decode_buffer(&p, end, &str, &sz) == -1) |
| 346 | return -1; |
| 347 | break; |
| 348 | } |
| 349 | |
| 350 | ret = (p - *buf); |
| 351 | *buf = p; |
| 352 | return ret; |
| 353 | } |
| 354 | |
| 355 | /* Decode a typed data and fill <smp>. If an error occurred, -1 is returned, |
| 356 | * otherwise the number of read bytes is returned and <*buf> is moved after the |
| 357 | * decoded data. See spoe_skip_data for details. */ |
| 358 | static inline int |
| 359 | spoe_decode_data(char **buf, char *end, struct sample *smp) |
| 360 | { |
| 361 | char *str, *p = *buf; |
| 362 | int type, r = 0; |
| 363 | uint64_t sz; |
| 364 | |
| 365 | if (p >= end) |
| 366 | return -1; |
| 367 | |
| 368 | type = *p++; |
| 369 | switch (type & SPOE_DATA_T_MASK) { |
| 370 | case SPOE_DATA_T_BOOL: |
| 371 | smp->data.u.sint = ((type & SPOE_DATA_FL_MASK) == SPOE_DATA_FL_TRUE); |
| 372 | smp->data.type = SMP_T_BOOL; |
| 373 | break; |
| 374 | case SPOE_DATA_T_INT32: |
| 375 | case SPOE_DATA_T_INT64: |
| 376 | case SPOE_DATA_T_UINT32: |
| 377 | case SPOE_DATA_T_UINT64: |
| 378 | if (decode_varint(&p, end, (uint64_t *)&smp->data.u.sint) == -1) |
| 379 | return -1; |
| 380 | smp->data.type = SMP_T_SINT; |
| 381 | break; |
| 382 | case SPOE_DATA_T_IPV4: |
| 383 | if (p+4 > end) |
| 384 | return -1; |
| 385 | smp->data.type = SMP_T_IPV4; |
| 386 | memcpy(&smp->data.u.ipv4, p, 4); |
| 387 | p += 4; |
| 388 | break; |
| 389 | case SPOE_DATA_T_IPV6: |
| 390 | if (p+16 > end) |
| 391 | return -1; |
| 392 | memcpy(&smp->data.u.ipv6, p, 16); |
| 393 | smp->data.type = SMP_T_IPV6; |
| 394 | p += 16; |
| 395 | break; |
| 396 | case SPOE_DATA_T_STR: |
| 397 | case SPOE_DATA_T_BIN: |
| 398 | /* All the buffer must be decoded */ |
| 399 | if (spoe_decode_buffer(&p, end, &str, &sz) == -1) |
| 400 | return -1; |
| 401 | smp->data.u.str.str = str; |
| 402 | smp->data.u.str.len = sz; |
| 403 | smp->data.type = (type == SPOE_DATA_T_STR) ? SMP_T_STR : SMP_T_BIN; |
| 404 | break; |
| 405 | } |
| 406 | |
| 407 | r = (p - *buf); |
| 408 | *buf = p; |
| 409 | return r; |
| 410 | } |
| 411 | |
| 412 | |
| 413 | #endif |