| /* LibTomCrypt, modular cryptographic library -- Tom St Denis |
| * |
| * LibTomCrypt is a library that provides various cryptographic |
| * algorithms in a highly modular and flexible manner. |
| * |
| * The library is free for all purposes without any express |
| * guarantee it works. |
| * |
| * Tom St Denis, tomstdenis@iahu.ca, http://libtomcrypt.org |
| */ |
| #include <stdarg.h> |
| #include "mycrypt.h" |
| |
| /* store multiple mp_ints in DER INTEGER format to the dst, will not |
| * overflow the length you give it [outlen] and store the number of |
| * bytes used in [outlen] |
| */ |
| int der_put_multi_integer(unsigned char *dst, unsigned long *outlen, |
| mp_int *num, ...) |
| { |
| va_list args; |
| mp_int *next; |
| unsigned long wrote, len; |
| int err; |
| |
| _ARGCHK(dst != NULL); |
| _ARGCHK(outlen != NULL); |
| |
| /* setup va list */ |
| next = num; |
| len = *outlen; |
| wrote = 0; |
| va_start(args, num); |
| |
| while (next != NULL) { |
| if ((err = der_encode_integer(next, dst, outlen)) != CRYPT_OK) { |
| va_end(args); |
| return err; |
| } |
| wrote += *outlen; |
| dst += *outlen; |
| len -= *outlen; |
| *outlen = len; |
| next = va_arg(args, mp_int*); |
| } |
| va_end(args); |
| *outlen = wrote; |
| return CRYPT_OK; |
| } |