base64.h File Reference

#include <cstddef>

Go to the source code of this file.

Classes
struct	base64_decode_context

Macros
#define	base64_decode(in, inlen, out, outlen)   base64_decode_ctx(NULL, in, inlen, out, outlen)
#define	base64_decode_alloc(in, inlen, out, outlen)   base64_decode_alloc_ctx(NULL, in, inlen, out, outlen)
#define	BASE64_LENGTH(inlen)   ((((inlen) + 2) / 3) * 4)

Functions
bool	base64_decode_alloc_ctx (struct base64_decode_context *ctx, const char *in, size_t inlen, char **out, size_t *outlen)
bool	base64_decode_ctx (struct base64_decode_context *ctx, const char *in, size_t inlen, char *out, size_t *outlen)
void	base64_decode_ctx_init (struct base64_decode_context *ctx)
void	base64_encode (const char *in, size_t inlen, char *out, size_t outlen)
size_t	base64_encode_alloc (const char *in, size_t inlen, char **out)
bool	isbase64 (char ch)

Macro Definition Documentation

base64_decode

#define base64_decode	(		in,
			inlen,
			out,
			outlen
	)		base64_decode_ctx(NULL, in, inlen, out, outlen)

Definition at line 52 of file base64.h.

base64_decode_alloc

#define base64_decode_alloc	(		in,
			inlen,
			out,
			outlen
	)		base64_decode_alloc_ctx(NULL, in, inlen, out, outlen)

Definition at line 54 of file base64.h.

BASE64_LENGTH

#define BASE64_LENGTH

(

inlen

)

((((inlen) + 2) / 3) * 4)

Definition at line 31 of file base64.h.

Function Documentation

base64_decode_alloc_ctx()

bool base64_decode_alloc_ctx	(	struct base64_decode_context *	ctx,
		const char *	in,
		size_t	inlen,
		char **	out,
		size_t *	outlen
	)

Definition at line 452 of file base64.cc.

                                                                                                 {
  /* This may allocate a few bytes too many, depending on input,
     but it's not worth the extra CPU time to compute the exact size.
     The exact size is 3 * (inlen + (ctx ? ctx->i : 0)) / 4, minus 1 if the
     input ends with "=" and minus another 1 if the input ends with "==".
     Dividing before multiplying avoids the possibility of overflow.  */
  size_t needlen = 3 * (inlen / 4) + 3;
 
  *out = static_cast<char *>(malloc(needlen));
  if (!*out)
    return true;
 
  if (!base64_decode_ctx(ctx, in, inlen, *out, &needlen)) {
    free(*out);
    *out = nullptr;
    return false;
  }
 
  if (outlen)
    *outlen = needlen;
 
  return true;
}

References base64_decode_ctx(), recoMuon::in, and MillePedeFileConverter_cfg::out.

base64_decode_ctx()

bool base64_decode_ctx	(	struct base64_decode_context *	ctx,
		const char *	in,
		size_t	inlen,
		char *	out,
		size_t *	outlen
	)

Definition at line 372 of file base64.cc.

                                                                                                                   {
  size_t outleft = *outlen;
  bool ignore_newlines = ctx != nullptr;
  bool flush_ctx = false;
  unsigned int ctx_i = 0;
 
  if (ignore_newlines) {
    ctx_i = ctx->i;
    flush_ctx = inlen == 0;
  }
 
  while (true) {
    size_t outleft_save = outleft;
    if (ctx_i == 0 && !flush_ctx) {
      while (true) {
        /* Save a copy of outleft, in case we need to re-parse this
                 block of four bytes.  */
        outleft_save = outleft;
        if (!decode_4(in, inlen, &out, &outleft))
          break;
 
        in += 4;
        inlen -= 4;
      }
    }
 
    if (inlen == 0 && !flush_ctx)
      break;
 
    /* Handle the common case of 72-byte wrapped lines.
         This also handles any other multiple-of-4-byte wrapping.  */
    if (inlen && *in == '\n' && ignore_newlines) {
      ++in;
      --inlen;
      continue;
    }
 
    /* Restore OUT and OUTLEFT.  */
    out -= outleft_save - outleft;
    outleft = outleft_save;
 
    {
      char const *in_end = in + inlen;
      char const *non_nl;
 
      if (ignore_newlines)
        non_nl = get_4(ctx, &in, in_end, &inlen);
      else
        non_nl = in; /* Might have nl in this case. */
 
      /* If the input is empty or consists solely of newlines (0 non-newlines),
           then we're done.  Likewise if there are fewer than 4 bytes when not
           flushing context and not treating newlines as garbage.  */
      if (inlen == 0 || (inlen < 4 && !flush_ctx && ignore_newlines)) {
        inlen = 0;
        break;
      }
      if (!decode_4(non_nl, inlen, &out, &outleft))
        break;
 
      inlen = in_end - in;
    }
  }
 
  *outlen -= outleft;
 
  return inlen == 0;
}

References decode_4(), get_4(), base64_decode_context::i, recoMuon::in, and MillePedeFileConverter_cfg::out.

Referenced by base64_decode_alloc_ctx().

base64_decode_ctx_init()

void base64_decode_ctx_init

(

struct base64_decode_context *

ctx

)

Definition at line 246 of file base64.cc.

{ ctx->i = 0; }

References base64_decode_context::i.

base64_encode()

void base64_encode	(	const char *	in,
		size_t	inlen,
		char *	out,
		size_t	outlen
	)

Definition at line 65 of file base64.cc.

                                                                           {
  static const char *b64str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
  while (inlen && outlen) {
    *out++ = b64str[(to_uchar(in[0]) >> 2) & 0x3f];
    if (!--outlen)
      break;
    *out++ = b64str[((to_uchar(in[0]) << 4) + (--inlen ? to_uchar(in[1]) >> 4 : 0)) & 0x3f];
    if (!--outlen)
      break;
    *out++ = (inlen ? b64str[((to_uchar(in[1]) << 2) + (--inlen ? to_uchar(in[2]) >> 6 : 0)) & 0x3f] : '=');
    if (!--outlen)
      break;
    *out++ = inlen ? b64str[to_uchar(in[2]) & 0x3f] : '=';
    if (!--outlen)
      break;
    if (inlen)
      inlen--;
    if (inlen)
      in += 3;
  }
 
  if (outlen)
    *out = '\0';
}

References b64str, recoMuon::in, MillePedeFileConverter_cfg::out, and to_uchar().

Referenced by base64_encode_alloc().

base64_encode_alloc()

size_t base64_encode_alloc	(	const char *	in,
		size_t	inlen,
		char **	out
	)

Definition at line 100 of file base64.cc.

                                                                     {
  size_t outlen = 1 + BASE64_LENGTH(inlen);
 
  /* Check for overflow in outlen computation.
   *
   * If there is no overflow, outlen >= inlen.
   *
   * If the operation (inlen + 2) overflows then it yields at most +1, so
   * outlen is 0.
   *
   * If the multiplication overflows, we lose at least half of the
   * correct value, so the result is < ((inlen + 2) / 3) * 2, which is
   * less than (inlen + 2) * 0.66667, which is less than inlen as soon as
   * (inlen > 4).
   */
  if (inlen > outlen) {
    *out = nullptr;
    return 0;
  }
 
  *out = static_cast<char *>(malloc(outlen));
  if (!*out)
    return outlen;
 
  base64_encode(in, inlen, *out, outlen);
 
  return outlen - 1;
}

References base64_encode(), BASE64_LENGTH, recoMuon::in, and MillePedeFileConverter_cfg::out.

Referenced by cond::auth::Cipher::b64encrypt().

isbase64()

bool isbase64

(

char

ch

)

Definition at line 243 of file base64.cc.

{ return uchar_in_range(to_uchar(ch)) && 0 <= b64[to_uchar(ch)]; }

References b64, to_uchar(), and uchar_in_range.

Referenced by decode_4().