nssb64e.c

来自「支持SSL v2/v3, TLS, PKCS #5, PKCS #7, PKCS」· C语言 代码 · 共 763 行 · 第 1/2 页

}

/*
 * Function to start a base64 encoding context.
 * An "output_fn" is required; the "output_arg" parameter to that is optional.
 * If linebreaks in the encoded output are desired, "line_length" specifies
 * where to place them -- it will be rounded down to the nearest multiple of 4
 * (if it is not already an even multiple of 4).  If it is zero, no linebreaks
 * will be added.  (FYI, a linebreak is CRLF -- two characters.)
 */
static PLBase64Encoder *
PL_CreateBase64Encoder (PRInt32 (*output_fn) (void *, const char *, PRInt32),
			void *output_arg, PRUint32 line_length)
{
    PLBase64Encoder *data;

    if (output_fn == NULL) {
	PR_SetError (PR_INVALID_ARGUMENT_ERROR, 0);
	return NULL;
    }

    data = pl_base64_create_encoder (line_length, NULL, 0);
    if (data == NULL)
	return NULL;

    data->output_fn = output_fn;
    data->output_arg = output_arg;

    return data;
}


/*
 * Push data through the encoder, causing the output_fn (provided to Create)
 * to be called with the encoded data.
 */
static PRStatus
PL_UpdateBase64Encoder (PLBase64Encoder *data, const unsigned char *buffer,
			PRUint32 size)
{
    /* XXX Should we do argument checking only in debug build? */
    if (data == NULL || buffer == NULL || size == 0) {
	PR_SetError (PR_INVALID_ARGUMENT_ERROR, 0);
	return PR_FAILURE;
    }

    return pl_base64_encode_buffer (data, buffer, size);
}


/*
 * When you're done encoding, call this to free the data.  If "abort_p"
 * is false, then calling this may cause the output_fn to be called
 * one last time (as the last buffered data is flushed out).
 */
static PRStatus
PL_DestroyBase64Encoder (PLBase64Encoder *data, PRBool abort_p)
{
    PRStatus status = PR_SUCCESS;

    /* XXX Should we do argument checking only in debug build? */
    if (data == NULL) {
	PR_SetError (PR_INVALID_ARGUMENT_ERROR, 0);
	return PR_FAILURE;
    }

    /* Flush out the last few buffered characters. */
    if (!abort_p)
	status = pl_base64_encode_flush (data);

    if (data->output_buffer != NULL)
	PR_Free(data->output_buffer);
    PR_Free(data);

    return status;
}


/*
 * Perform base64 encoding from an input buffer to an output buffer.
 * The output buffer can be provided (as "dest"); you can also pass in
 * a NULL and this function will allocate a buffer large enough for you,
 * and return it.  If you do provide the output buffer, you must also
 * provide the maximum length of that buffer (as "maxdestlen").
 * The actual encoded length of output will be returned to you in
 * "output_destlen".
 *
 * If linebreaks in the encoded output are desired, "line_length" specifies
 * where to place them -- it will be rounded down to the nearest multiple of 4
 * (if it is not already an even multiple of 4).  If it is zero, no linebreaks
 * will be added.  (FYI, a linebreak is CRLF -- two characters.)
 *
 * Return value is NULL on error, the output buffer (allocated or provided)
 * otherwise.
 */
static char *
PL_Base64EncodeBuffer (const unsigned char *src, PRUint32 srclen,
		       PRUint32 line_length, char *dest, PRUint32 maxdestlen,
		       PRUint32 *output_destlen)
{
    PRUint32 need_length;
    PLBase64Encoder *data = NULL;
    PRStatus status;

    PR_ASSERT(srclen > 0);
    if (srclen == 0)
	return dest;

    /*
     * How much space could we possibly need for encoding this input?
     */
    need_length = PL_Base64MaxEncodedLength (srclen, line_length);

    /*
     * Make sure we have at least that much, if output buffer provided.
     */
    if (dest != NULL) {
	PR_ASSERT(maxdestlen >= need_length);
	if (maxdestlen < need_length) {
	    PR_SetError(PR_BUFFER_OVERFLOW_ERROR, 0);
	    return NULL;
	}
    } else {
	maxdestlen = need_length;
    }

    data = pl_base64_create_encoder(line_length, dest, maxdestlen);
    if (data == NULL)
	return NULL;

    status = pl_base64_encode_buffer (data, src, srclen);

    /*
     * We do not wait for Destroy to flush, because Destroy will also
     * get rid of our encoder context, which we need to look at first!
     */
    if (status == PR_SUCCESS)
	status = pl_base64_encode_flush (data);

    if (status != PR_SUCCESS) {
	(void) PL_DestroyBase64Encoder (data, PR_TRUE);
	return NULL;
    }

    dest = data->output_buffer;

    /* Must clear this or Destroy will free it. */
    data->output_buffer = NULL;

    *output_destlen = data->output_length;
    status = PL_DestroyBase64Encoder (data, PR_FALSE);
    if (status == PR_FAILURE) {
	PR_Free(dest);
	return NULL;
    }

    return dest;
}

/*
 * XXX End of base64 encoding code to be moved into NSPR.
 ********************************************************
 */

/*
 * This is the beginning of the NSS cover functions.  These will
 * provide the interface we want to expose as NSS-ish.  For example,
 * they will operate on our Items, do any special handling or checking
 * we want to do, etc.
 */


PR_BEGIN_EXTERN_C

/*
 * A boring cover structure for now.  Perhaps someday it will include
 * some more interesting fields.
 */
struct NSSBase64EncoderStr {
    PLBase64Encoder *pl_data;
};

PR_END_EXTERN_C


/*
 * Function to start a base64 encoding context.
 */
NSSBase64Encoder *
NSSBase64Encoder_Create (PRInt32 (*output_fn) (void *, const char *, PRInt32),
			 void *output_arg)
{
    PLBase64Encoder *pl_data;
    NSSBase64Encoder *nss_data;

    nss_data = PORT_ZNew(NSSBase64Encoder);
    if (nss_data == NULL)
	return NULL;

    pl_data = PL_CreateBase64Encoder (output_fn, output_arg, 64);
    if (pl_data == NULL) {
	PORT_Free(nss_data);
	return NULL;
    }

    nss_data->pl_data = pl_data;
    return nss_data;
}


/*
 * Push data through the encoder, causing the output_fn (provided to Create)
 * to be called with the encoded data.
 */
SECStatus
NSSBase64Encoder_Update (NSSBase64Encoder *data, const unsigned char *buffer,
			 PRUint32 size)
{
    PRStatus pr_status;

    /* XXX Should we do argument checking only in debug build? */
    if (data == NULL) {
	PORT_SetError (SEC_ERROR_INVALID_ARGS);
	return SECFailure;
    }

    pr_status = PL_UpdateBase64Encoder (data->pl_data, buffer, size);
    if (pr_status == PR_FAILURE)
	return SECFailure;

    return SECSuccess;
}


/*
 * When you're done encoding, call this to free the data.  If "abort_p"
 * is false, then calling this may cause the output_fn to be called
 * one last time (as the last buffered data is flushed out).
 */
SECStatus
NSSBase64Encoder_Destroy (NSSBase64Encoder *data, PRBool abort_p)
{
    PRStatus pr_status;

    /* XXX Should we do argument checking only in debug build? */
    if (data == NULL) {
	PORT_SetError (SEC_ERROR_INVALID_ARGS);
	return SECFailure;
    }

    pr_status = PL_DestroyBase64Encoder (data->pl_data, abort_p);

    PORT_Free(data);

    if (pr_status == PR_FAILURE)
	return SECFailure;

    return SECSuccess;
}


/*
 * Perform base64 encoding of binary data "inItem" to an ascii string.
 * The output buffer may be provided (as "outStrOpt"); you can also pass
 * in a NULL and the buffer will be allocated for you.  The result will
 * be null-terminated, and if the buffer is provided, "maxOutLen" must
 * specify the maximum length of the buffer and will be checked to
 * supply sufficient space space for the encoded result.  (If "outStrOpt"
 * is NULL, "maxOutLen" is ignored.)
 *
 * If "outStrOpt" is NULL, allocation will happen out of the passed-in
 * "arenaOpt", if *it* is non-NULL, otherwise standard allocation (heap)
 * will be used.
 *
 * Return value is NULL on error, the output buffer (allocated or provided)
 * otherwise.
 */
char *
NSSBase64_EncodeItem (PRArenaPool *arenaOpt, char *outStrOpt,
		      unsigned int maxOutLen, SECItem *inItem)
{
    char *out_string = outStrOpt;
    PRUint32 max_out_len;
    PRUint32 out_len;
    void *mark = NULL;
    char *dummy;

    PORT_Assert(inItem != NULL && inItem->data != NULL && inItem->len != 0);
    if (inItem == NULL || inItem->data == NULL || inItem->len == 0) {
	PORT_SetError (SEC_ERROR_INVALID_ARGS);
	return NULL;
    }

    max_out_len = PL_Base64MaxEncodedLength (inItem->len, 64);

    if (arenaOpt != NULL)
	mark = PORT_ArenaMark (arenaOpt);

    if (out_string == NULL) {
	if (arenaOpt != NULL)
	    out_string = PORT_ArenaAlloc (arenaOpt, max_out_len + 1);
	else
	    out_string = PORT_Alloc (max_out_len + 1);

	if (out_string == NULL) {
	    if (arenaOpt != NULL)
		PORT_ArenaRelease (arenaOpt, mark);
	    return NULL;
	}
    } else {
	if ((max_out_len + 1) > maxOutLen) {
	    PORT_SetError (SEC_ERROR_OUTPUT_LEN);
	    return NULL;
	}
	max_out_len = maxOutLen;
    }


    dummy = PL_Base64EncodeBuffer (inItem->data, inItem->len, 64,
				   out_string, max_out_len, &out_len);
    if (dummy == NULL) {
	if (arenaOpt != NULL) {
	    PORT_ArenaRelease (arenaOpt, mark);
	} else {
	    PORT_Free (out_string);
	}
	return NULL;
    }

    if (arenaOpt != NULL)
	PORT_ArenaUnmark (arenaOpt, mark);

    out_string[out_len] = '\0';
    return out_string;
}


/*
 * XXX Everything below is deprecated.  If you add new stuff, put it
 * *above*, not below.
 */

/*
 * XXX The following "BTOA" functions are provided for backward compatibility
 * with current code.  They should be considered strongly deprecated.
 * When we can convert all our code over to using the new NSSBase64Encoder_
 * functions defined above, we should get rid of these altogether.  (Remove
 * protoypes from base64.h as well -- actually, remove that file completely).
 * If someone thinks either of these functions provides such a very useful
 * interface (though, as shown, the same functionality can already be
 * obtained by calling NSSBase64_EncodeItem directly), fine -- but then
 * that API should be provided with a nice new NSSFoo name and using
 * appropriate types, etc.
 */

#include "base64.h"

/*
** Return an PORT_Alloc'd ascii string which is the base64 encoded
** version of the input string.
*/
char *
BTOA_DataToAscii(const unsigned char *data, unsigned int len)
{
    SECItem binary_item;

    binary_item.data = (unsigned char *)data;
    binary_item.len = len;

    return NSSBase64_EncodeItem (NULL, NULL, 0, &binary_item);
}

/*
** Convert from binary encoding of an item to ascii.
*/
char *
BTOA_ConvertItemToAscii (SECItem *binary_item)
{
    return NSSBase64_EncodeItem (NULL, NULL, 0, binary_item);
}