/*
* Transform an armored document in binary format
* Used on public keys and signatures
*/
static int pgp_unarmor(const char *p_ibuf, size_t i_ibuf_len, uint8_t *p_obuf, size_t i_obuf_len)
{
const char *p_ipos = p_ibuf;
uint8_t *p_opos = p_obuf;
int i_end = 0;
int i_header_skipped = 0;
while (!i_end && p_ipos < p_ibuf + i_ibuf_len && *p_ipos != '=')
{
if (*p_ipos == '\r' || *p_ipos == '\n')
{
p_ipos++;
continue;
}
size_t i_line_len = strcspn(p_ipos, "\r\n");
if (i_line_len == 0)
continue;
if (!i_header_skipped)
{
if (!strncmp(p_ipos, "-----BEGIN PGP", 14))
i_header_skipped = 1;
p_ipos += i_line_len + 1;
continue;
}
if (!strncmp(p_ipos, "Version:", 8))
{
p_ipos += i_line_len + 1;
continue;
}
if (p_ipos[i_line_len - 1] == '=')
{
i_end = 1;
}
p_opos += b64_decode_binary_to_buffer(p_opos, p_obuf - p_opos + i_obuf_len, p_ipos, (int)i_line_len);
p_ipos += i_line_len + 1;
}
if (p_ipos + 1 < p_ibuf + i_ibuf_len && (*p_ipos == '\r' || *p_ipos == '\n'))
p_ipos++;
/* XXX: the CRC is OPTIONAL, really require it ? */
if (p_ipos + 5 > p_ibuf + i_ibuf_len || *p_ipos++ != '=')
return 0;
uint8_t p_crc[3];
if (b64_decode_binary_to_buffer(p_crc, sizeof(p_crc), p_ipos, 5) != 3)
return 0;
long l_crc = crc_octets(p_obuf, p_opos - p_obuf);
long l_crc2 = (0 << 24) + (p_crc[0] << 16) + (p_crc[1] << 8) + p_crc[2];
return (int)((l_crc2 == l_crc) ? p_opos - p_obuf : 0);
}
value caml_crc_octets(value data) {
CAMLparam1(data);
CAMLlocal1(rval);
char *octets = String_val(data);
size_t len = string_length(data);
long crc = crc_octets(octets,len);
rval = Val_int(crc);
CAMLreturn(rval);
}
