| // SPDX-License-Identifier: BSD-2-Clause |
| /* 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. |
| */ |
| #include "tomcrypt_private.h" |
| |
| /** |
| @file base64_encode.c |
| Compliant base64 encoder donated by Wayne Scott (wscott@bitmover.com) |
| base64 URL Safe variant (RFC 4648 section 5) by Karel Miko |
| */ |
| |
| |
| #if defined(LTC_BASE64) || defined (LTC_BASE64_URL) |
| |
| #if defined(LTC_BASE64) |
| static const char * const codes_base64 = |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| #endif /* LTC_BASE64 */ |
| |
| #if defined(LTC_BASE64_URL) |
| static const char * const codes_base64url = |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_"; |
| #endif /* LTC_BASE64_URL */ |
| |
| static int _base64_encode_internal(const unsigned char *in, unsigned long inlen, |
| char *out, unsigned long *outlen, |
| const char *codes, int pad) |
| { |
| unsigned long i, len2, leven; |
| char *p; |
| |
| LTC_ARGCHK(in != NULL); |
| LTC_ARGCHK(out != NULL); |
| LTC_ARGCHK(outlen != NULL); |
| |
| /* valid output size ? */ |
| len2 = 4 * ((inlen + 2) / 3); |
| if (*outlen < len2 + 1) { |
| *outlen = len2 + 1; |
| return CRYPT_BUFFER_OVERFLOW; |
| } |
| p = out; |
| leven = 3*(inlen / 3); |
| for (i = 0; i < leven; i += 3) { |
| *p++ = codes[(in[0] >> 2) & 0x3F]; |
| *p++ = codes[(((in[0] & 3) << 4) + (in[1] >> 4)) & 0x3F]; |
| *p++ = codes[(((in[1] & 0xf) << 2) + (in[2] >> 6)) & 0x3F]; |
| *p++ = codes[in[2] & 0x3F]; |
| in += 3; |
| } |
| /* Pad it if necessary... */ |
| if (i < inlen) { |
| unsigned a = in[0]; |
| unsigned b = (i+1 < inlen) ? in[1] : 0; |
| |
| *p++ = codes[(a >> 2) & 0x3F]; |
| *p++ = codes[(((a & 3) << 4) + (b >> 4)) & 0x3F]; |
| if (pad) { |
| *p++ = (i+1 < inlen) ? codes[(((b & 0xf) << 2)) & 0x3F] : '='; |
| *p++ = '='; |
| } |
| else { |
| if (i+1 < inlen) *p++ = codes[(((b & 0xf) << 2)) & 0x3F]; |
| } |
| } |
| |
| /* append a NULL byte */ |
| *p = '\0'; |
| |
| /* return ok */ |
| *outlen = (unsigned long)(p - out); /* the length without terminating NUL */ |
| return CRYPT_OK; |
| } |
| |
| #if defined(LTC_BASE64) |
| /** |
| base64 Encode a buffer (NUL terminated) |
| @param in The input buffer to encode |
| @param inlen The length of the input buffer |
| @param out [out] The destination of the base64 encoded data |
| @param outlen [in/out] The max size and resulting size |
| @return CRYPT_OK if successful |
| */ |
| int base64_encode(const unsigned char *in, unsigned long inlen, |
| char *out, unsigned long *outlen) |
| { |
| return _base64_encode_internal(in, inlen, out, outlen, codes_base64, 1); |
| } |
| #endif /* LTC_BASE64 */ |
| |
| |
| #if defined(LTC_BASE64_URL) |
| /** |
| base64 (URL Safe, RFC 4648 section 5) Encode a buffer (NUL terminated) |
| @param in The input buffer to encode |
| @param inlen The length of the input buffer |
| @param out [out] The destination of the base64 encoded data |
| @param outlen [in/out] The max size and resulting size |
| @return CRYPT_OK if successful |
| */ |
| int base64url_encode(const unsigned char *in, unsigned long inlen, |
| char *out, unsigned long *outlen) |
| { |
| return _base64_encode_internal(in, inlen, out, outlen, codes_base64url, 0); |
| } |
| |
| int base64url_strict_encode(const unsigned char *in, unsigned long inlen, |
| char *out, unsigned long *outlen) |
| { |
| return _base64_encode_internal(in, inlen, out, outlen, codes_base64url, 1); |
| } |
| #endif /* LTC_BASE64_URL */ |
| |
| #endif |
| |
| |
| /* ref: $Format:%D$ */ |
| /* git commit: $Format:%H$ */ |
| /* commit time: $Format:%ai$ */ |