crypto/asn1/f_string.c

   1 /*
   2  * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include "crypto/ctype.h"
  12 #include "internal/cryptlib.h"
  13 #include <openssl/buffer.h>
  14 #include <openssl/asn1.h>
  15
  16 int i2a_ASN1_STRING(BIO *bp, const ASN1_STRING *a, int type)
  17 {
  18     int i, n = 0;
  19     static const char *h = "0123456789ABCDEF";
  20     char buf[2];
  21
  22     if (a == NULL)
  23         return 0;
  24
  25     if (a->length == 0) {
  26         if (BIO_write(bp, "0", 1) != 1)
  27             goto err;
  28         n = 1;
  29     } else {
  30         for (i = 0; i < a->length; i++) {
  31             if ((i != 0) && (i % 35 == 0)) {
  32                 if (BIO_write(bp, "\\\n", 2) != 2)
  33                     goto err;
  34                 n += 2;
  35             }
  36             buf[0] = h[((unsigned char)a->data[i] >> 4) & 0x0f];
  37             buf[1] = h[((unsigned char)a->data[i]) & 0x0f];
  38             if (BIO_write(bp, buf, 2) != 2)
  39                 goto err;
  40             n += 2;
  41         }
  42     }
  43     return n;
  44  err:
  45     return -1;
  46 }
  47
  48 int a2i_ASN1_STRING(BIO *bp, ASN1_STRING *bs, char *buf, int size)
  49 {
  50     int i, j, k, m, n, again, bufsize;
  51     unsigned char *s = NULL, *sp;
  52     unsigned char *bufp;
  53     int num = 0, slen = 0, first = 1;
  54
  55     bufsize = BIO_gets(bp, buf, size);
  56     for (;;) {
  57         if (bufsize < 1) {
  58             if (first)
  59                 break;
  60             else
  61                 goto err;
  62         }
  63         first = 0;
  64
  65         i = bufsize;
  66         if (buf[i - 1] == '\n')
  67             buf[--i] = '\0';
  68         if (i == 0)
  69             goto err;
  70         if (buf[i - 1] == '\r')
  71             buf[--i] = '\0';
  72         if (i == 0)
  73             goto err;
  74         again = (buf[i - 1] == '\\');
  75
  76         for (j = i - 1; j > 0; j--) {
  77             if (!ossl_isxdigit(buf[j])) {
  78                 i = j;
  79                 break;
  80             }
  81         }
  82         buf[i] = '\0';
  83         /*
  84          * We have now cleared all the crap off the end of the line
  85          */
  86         if (i < 2)
  87             goto err;
  88
  89         bufp = (unsigned char *)buf;
  90
  91         k = 0;
  92         i -= again;
  93         if (i % 2 != 0) {
  94             ERR_raise(ERR_LIB_ASN1, ASN1_R_ODD_NUMBER_OF_CHARS);
  95             OPENSSL_free(s);
  96             return 0;
  97         }
  98         i /= 2;
  99         if (num + i > slen) {
 100             sp = OPENSSL_realloc(s, (unsigned int)num + i * 2);
 101             if (sp == NULL) {
 102                 ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
 103                 OPENSSL_free(s);
 104                 return 0;
 105             }
 106             s = sp;
 107             slen = num + i * 2;
 108         }
 109         for (j = 0; j < i; j++, k += 2) {
 110             for (n = 0; n < 2; n++) {
 111                 m = OPENSSL_hexchar2int(bufp[k + n]);
 112                 if (m < 0) {
 113                     ERR_raise(ERR_LIB_ASN1, ASN1_R_NON_HEX_CHARACTERS);
 114                     OPENSSL_free(s);
 115                     return 0;
 116                 }
 117                 s[num + j] <<= 4;
 118                 s[num + j] |= m;
 119             }
 120         }
 121         num += i;
 122         if (again)
 123             bufsize = BIO_gets(bp, buf, size);
 124         else
 125             break;
 126     }
 127     bs->length = num;
 128     bs->data = s;
 129     return 1;
 130
 131  err:
 132     ERR_raise(ERR_LIB_ASN1, ASN1_R_SHORT_LINE);
 133     OPENSSL_free(s);
 134     return 0;
 135 }