src/utils.c

   1 #include "isds_priv.h"
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <iconv.h>
   6 #ifndef _WIN32
   7 #include <langinfo.h>
   8 #endif
   9 #include <limits.h>
  10 #include <time.h>
  11 #include <errno.h>
  12 #include "utils.h"
  13 #include "cencode.h"
  14 #include "cdecode.h"
  15 #include "system.h"
  16
  17 /* Concatenate two strings into newly allocated buffer.
  18  * You must free() them, when you don't need it anymore.
  19  * Any of the arguments can be NULL meaning empty string.
  20  * In case of error returns NULL.
  21  * Empty string is always returned as allocated empty string. */
  22 _hidden char *_isds_astrcat(const char *first, const char *second) {
  23     size_t first_len, second_len;
  24     char *buf;
  25
  26     first_len = (first) ? strlen(first) : 0;
  27     second_len = (second) ? strlen(second) : 0;
  28     buf = malloc(1 + first_len + second_len);
  29     if (buf) {
  30         buf[0] = '\0';
  31         if (first) strcpy(buf, first);
  32         if (second) strcpy(buf + first_len, second);
  33     }
  34     return buf;
  35 }
  36
  37
  38 /* Concatenate three strings into newly allocated buffer.
  39  * You must free() them, when you don't need it anymore.
  40  * Any of the arguments can be NULL meaning empty string.
  41  * In case of error returns NULL.
  42  * Empty string is always returned as allocated empty string. */
  43 _hidden char *_isds_astrcat3(const char *first, const char *second,
  44         const char *third) {
  45     size_t first_len, second_len, third_len;
  46     char *buf, *next;
  47
  48     first_len = (first) ? strlen(first) : 0;
  49     second_len = (second) ? strlen(second) : 0;
  50     third_len = (third) ? strlen(third) : 0;
  51     buf = malloc(1 + first_len + second_len + third_len);
  52     if (buf) {
  53         buf[0] = '\0';
  54         next = buf;
  55         if (first) {
  56             strcpy(next, first);
  57             next += first_len;
  58         }
  59         if (second) {
  60             strcpy(next, second);
  61             next += second_len;
  62         }
  63         if (third) {
  64             strcpy(next, third);
  65         }
  66     }
  67     return buf;
  68 }
  69
  70
  71 /* Print formatted string into automatically reallocated @buffer.
  72  * @buffer automatically reallocated buffer. Must be &NULL or preallocated
  73  * memory.
  74  * @format format string as for printf(3)
  75  * @ap list of variadic arguments, after call will be in undefined state
  76  * @Returns number of bytes printed. In case of error, -1 and NULL @buffer*/
  77 _hidden int isds_vasprintf(char **buffer, const char *format, va_list ap) {
  78     va_list aq;
  79     int length, new_length;
  80     char *new_buffer;
  81
  82     if (!buffer || !format) {
  83         if (buffer) {
  84             free(*buffer);
  85             *buffer = NULL;
  86         }
  87         return -1;
  88     }
  89
  90     va_copy(aq, ap);
  91     length = vsnprintf(NULL, 0, format, aq) + 1;
  92     va_end(aq);
  93     if (length <= 0) {
  94         free(*buffer);
  95         *buffer = NULL;
  96         return -1;
  97     }
  98
  99     new_buffer = realloc(*buffer, length);
 100     if (!new_buffer) {
 101         free(*buffer);
 102         *buffer = NULL;
 103         return -1;
 104     }
 105     *buffer = new_buffer;
 106
 107     new_length = vsnprintf(*buffer, length, format, ap);
 108     if (new_length >= length) {
 109         free(*buffer);
 110         *buffer = NULL;
 111         return -1;
 112     }
 113
 114     return new_length;
 115 }
 116
 117
 118 /* Print formatted string into automatically reallocated @buffer.
 119  * @buffer automatically reallocated buffer. Must be &NULL or preallocated
 120  * memory.
 121  * @format format string as for printf(3)
 122  * @... variadic arguments
 123  * @Returns number of bytes printed. In case of error, -1 and NULL @buffer */
 124 _hidden int isds_asprintf(char **buffer, const char *format, ...) {
 125     int ret;
 126     va_list ap;
 127     va_start(ap, format);
 128     ret = isds_vasprintf(buffer, format, ap);
 129     va_end(ap);
 130     return ret;
 131 }
 132
 133 /* Converts a block from charset to charset.
 134  * @from is input charset of @input block as known to iconv
 135  * @to is output charset @input will be converted to @output
 136  * @input is block in @from charset/encoding of length @input_length
 137  * @input_length is size of @input block in bytes
 138  * @output is automatically allocated block of data converted from @input. No
 139  * NUL is apended. Can be NULL, if resulting size is 0. You must free it.
 140  * @return size of @output in bytes. In case of error returns (size_t) -1 and
 141  * deallocates @output if this function allocated it in this call. */
 142 _hidden size_t _isds_any2any(const char *from, const char *to,
 143         const void *input, size_t input_length, void **output) {
 144     iconv_t state;
 145     char *buffer = NULL, *new_buffer;
 146     size_t buffer_length = 0, buffer_used = 0;
 147     char *inbuf, *outbuf;
 148     size_t inleft, outleft;
 149
 150     if (output != NULL) *output = NULL;
 151     if (from == NULL || to == NULL || input == NULL || output == NULL)
 152         return (size_t) -1;
 153
 154     state = iconv_open(to, from);
 155     if (state == (iconv_t) -1) return (size_t) -1;
 156
 157     /* Get the initial output buffer length */
 158     buffer_length = input_length;
 159
 160     inbuf = (char *) input;
 161     inleft = input_length;
 162
 163     while (inleft > 0) {
 164         /* Extend buffer */
 165         new_buffer = realloc(buffer, buffer_length);
 166         if (!new_buffer) {
 167             zfree(buffer);
 168             buffer_used = (size_t) -1;
 169             goto leave;
 170         }
 171         buffer = new_buffer;
 172
 173         /* FIXME */
 174         outbuf = buffer + buffer_used;
 175         outleft = buffer_length - buffer_used;
 176
 177         /* Convert chunk of data */
 178         if ((size_t) -1 == iconv(state, &inbuf, &inleft, &outbuf, &outleft) &&
 179                 errno != E2BIG) {
 180             zfree(buffer);
 181             buffer_used = (size_t) -1;
 182             goto leave;
 183         }
 184
 185         /* Update positions */
 186         buffer_length += 1024;
 187         buffer_used = outbuf - buffer;
 188     }
 189
 190 leave:
 191     iconv_close(state);
 192     if (buffer_used == 0) zfree(buffer);
 193     *output = buffer;
 194     return buffer_used;
 195 }
 196
 197 /* Converts UTF8 string into locale encoded string.
 198  * @utf string int UTF-8 terminated by zero byte
 199  * @return allocated string encoded in locale specific encoding. You must free
 200  * it. In case of error or NULL @utf returns NULL. */
 201 _hidden char *_isds_utf82locale(const char *utf) {
 202     char *output, *bigger_output;
 203     size_t length;
 204
 205     if (utf == NULL) return NULL;
 206
 207     length = _isds_any2any("UTF-8", nl_langinfo(CODESET), utf, strlen(utf),
 208             (void **) &output);
 209     if (length == (size_t) -1) return NULL;
 210
 211     bigger_output = realloc(output, length + 1);
 212     if (bigger_output == NULL) {
 213         zfree(output);
 214     } else {
 215         output = bigger_output;
 216         output[length] = '\0';
 217     }
 218
 219     return output;
 220 }
 221
 222
 223 /* Encode given data into MIME Base64 encoded zero terminated string.
 224  * @plain are input data (binary stream)
 225  * @length is length of @plain data in bytes
 226  * @return allocated string of base64 encoded plain data or NULL in case of
 227  * error. You must free it. */
 228 _hidden char *_isds_b64encode(const void *plain, const size_t length) {
 229
 230     base64_encodestate state;
 231     size_t code_length;
 232     char *buffer, *new_buffer;
 233
 234     if (!plain) {
 235         if (length) return NULL;
 236         /* Empty input is valid input */
 237         plain = "";
 238     }
 239
 240     _isds_base64_init_encodestate(&state);
 241
 242     /* Allocate buffer
 243      * (4 is padding, 1 is final new line, and 1 is string terminator) */
 244     buffer = malloc(length * 2 + 4 + 1 + 1);
 245     if (!buffer) return NULL;
 246
 247     /* Encode plain data */
 248     code_length = _isds_base64_encode_block(plain, length, (int8_t *)buffer,
 249             &state);
 250     code_length += _isds_base64_encode_blockend(((int8_t*)buffer) + code_length,
 251             &state);
 252
 253     /* Terminate string */
 254     buffer[code_length++] = '\0';
 255
 256     /* Shrink the buffer */
 257     new_buffer = realloc(buffer, code_length);
 258     if (new_buffer) buffer = new_buffer;
 259
 260     return buffer;
 261 }
 262
 263
 264 /* Decode given data from MIME Base64 encoded zero terminated string to binary
 265  * stream. Invalid Base64 symbols are skipped.
 266  * @encoded are input data (Base64 zero terminated string)
 267  * @plain are automatically reallocated output data (binary stream). You must
 268  * free it. Will be freed in case of error.
 269  * @return length of @plain data in bytes or (size_t) -1 in case of memory
 270  * allocation failure. */
 271 _hidden size_t _isds_b64decode(const char *encoded, void **plain) {
 272
 273     base64_decodestate state;
 274     size_t encoded_length;
 275     size_t plain_length;
 276     char *buffer;
 277
 278     if (NULL == encoded || NULL == plain) {
 279         if (NULL != plain) zfree(*plain);
 280         return ((size_t) -1);
 281     }
 282
 283     encoded_length = strlen(encoded);
 284     _isds_base64_init_decodestate(&state);
 285
 286     /* Divert empty input */
 287     if (encoded_length == 0) {
 288         zfree(*plain);
 289         return 0;
 290     }
 291
 292     /* Allocate buffer */
 293     buffer = realloc(*plain, encoded_length);
 294     if (NULL == buffer) {
 295         zfree(*plain);
 296         return ((size_t) -1);
 297     }
 298     *plain = buffer;
 299
 300     /* Decode encoded data */
 301     plain_length = _isds_base64_decode_block((const int8_t *)encoded,
 302             encoded_length, *plain, &state);
 303     if (plain_length >= (size_t) -1) {
 304         zfree(*plain);
 305         return((size_t) -1);
 306     }
 307
 308     /* Shrink the buffer */
 309     if (0 == plain_length) {
 310         zfree(*plain);
 311     } else {
 312         buffer = realloc(*plain, plain_length);
 313         /* realloc() can move pointer even when shrinking */
 314         if (NULL != buffer) *plain = buffer;
 315     }
 316
 317     return plain_length;
 318 }
 319
 320
 321 /* Convert hexadecimal digit to integer. Return negative value if character is
 322  * not valid hexadecimal digit. */
 323 _hidden int _isds_hex2i(char digit) {
 324     if (digit >= '0' && digit <= '9')
 325         return digit - '0';
 326     if (digit >= 'a' && digit <= 'f')
 327         return digit - 'a' + 10;
 328     if (digit >= 'A' && digit <= 'F')
 329         return digit - 'A' + 10;
 330     return -1;
 331 }
 332
 333
 334 /* Convert size_t to int. */
 335 _hidden int _isds_sizet2int(size_t val) {
 336     return (val <= INT_MAX) ? (int) val : -1;
 337 }