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