printcert/util.c

   1 #include "rfc3280.h"
   2
   3 #include "util.h"
   4
   5 #define BUFFER_LENGTH 4096
   6
   7 static A2C_ERROR _A2C_DecodeBerFile(PVOID * ppv, PC_A2C_DESCRIPTOR pdesc, int flags, FILE* file)
   8 {
   9     unsigned char buffer[BUFFER_LENGTH];
  10     int return_code = 0;
  11     A2C_CONTEXT* pcxt = NULL;
  12     A2C_ERROR err = A2C_ERROR_Success;
  13
  14     while (1)
  15     {
  16         return_code = fread(buffer, 1, sizeof(buffer), file);
  17
  18         if (return_code < 0)
  19         {
  20             err = A2C_ERROR_malformedEncoding;
  21             break;
  22         }
  23
  24         if (return_code == 0)
  25         {
  26             break;
  27         }
  28
  29         err = A2C_DecodeBer(
  30             ppv,
  31             pdesc,
  32             flags,
  33             &pcxt,
  34             buffer,
  35             return_code
  36             );
  37         if ((err < A2C_ERROR_Success) && (err != A2C_ERROR_needMoreData))
  38         {
  39             break;
  40         }
  41
  42         flags |= A2C_FLAGS_MORE_DATA;
  43     }
  44
  45     if ((err < A2C_ERROR_Success) && (pcxt != NULL))
  46     {
  47         /* A2C_FreeContext(pcxt); */
  48     }
  49
  50     return err;
  51 }
  52
  53 Cert_Certificate* read_certificate_from_file(const char* filename)
  54 {
  55     A2C_ERROR err = A2C_ERROR_Success;
  56     Cert_Certificate* certificate = NULL;
  57     FILE* file = NULL;
  58
  59     file = fopen(filename, "rb");
  60     if (file == NULL)
  61     {
  62         perror(filename);
  63         return NULL;
  64     }
  65
  66     err = _A2C_DecodeBerFile(
  67         (PVOID*) &certificate,
  68         &Cert_Certificate_descriptor,
  69         0,
  70         file
  71         );
  72
  73     (void) fclose(file);
  74
  75     if (err < A2C_ERROR_Success)
  76     {
  77         return NULL;
  78     }
  79
  80     return certificate;
  81 }