2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
12 #include "internal/cryptlib.h"
13 #include <openssl/buffer.h>
14 #include <openssl/evp.h>
15 #include "internal/bio.h"
17 static int b64_write(BIO *h, const char *buf, int num);
18 static int b64_read(BIO *h, char *buf, int size);
19 static int b64_puts(BIO *h, const char *str);
20 static long b64_ctrl(BIO *h, int cmd, long arg1, void *arg2);
21 static int b64_new(BIO *h);
22 static int b64_free(BIO *data);
23 static long b64_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
24 #define B64_BLOCK_SIZE 1024
25 #define B64_BLOCK_SIZE2 768
30 typedef struct b64_struct {
32 * BIO *bio; moved to the BIO structure
36 int tmp_len; /* used to find the start when decoding */
37 int tmp_nl; /* If true, scan until '\n' */
39 int start; /* have we started decoding yet? */
40 int cont; /* <= 0 when finished */
41 EVP_ENCODE_CTX *base64;
42 char buf[EVP_ENCODE_LENGTH(B64_BLOCK_SIZE) + 10];
43 char tmp[B64_BLOCK_SIZE];
46 static const BIO_METHOD methods_b64 = {
47 BIO_TYPE_BASE64, "base64 encoding",
48 /* TODO: Convert to new style write function */
51 /* TODO: Convert to new style read function */
63 const BIO_METHOD *BIO_f_base64(void)
68 static int b64_new(BIO *bi)
72 ctx = OPENSSL_zalloc(sizeof(*ctx));
78 ctx->base64 = EVP_ENCODE_CTX_new();
79 if (ctx->base64 == NULL) {
84 BIO_set_data(bi, ctx);
90 static int b64_free(BIO *a)
96 ctx = BIO_get_data(a);
100 EVP_ENCODE_CTX_free(ctx->base64);
102 BIO_set_data(a, NULL);
108 static int b64_read(BIO *b, char *out, int outl)
110 int ret = 0, i, ii, j, k, x, n, num, ret_code = 0;
112 unsigned char *p, *q;
117 ctx = (BIO_B64_CTX *)BIO_get_data(b);
120 if ((ctx == NULL) || (next == NULL))
123 BIO_clear_retry_flags(b);
125 if (ctx->encode != B64_DECODE) {
126 ctx->encode = B64_DECODE;
130 EVP_DecodeInit(ctx->base64);
133 /* First check if there are bytes decoded/encoded */
134 if (ctx->buf_len > 0) {
135 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
136 i = ctx->buf_len - ctx->buf_off;
139 OPENSSL_assert(ctx->buf_off + i < (int)sizeof(ctx->buf));
140 memcpy(out, &(ctx->buf[ctx->buf_off]), i);
145 if (ctx->buf_len == ctx->buf_off) {
152 * At this point, we have room of outl bytes and an empty buffer, so we
153 * should read in some more.
161 i = BIO_read(next, &(ctx->tmp[ctx->tmp_len]),
162 B64_BLOCK_SIZE - ctx->tmp_len);
167 /* Should we continue next time we are called? */
168 if (!BIO_should_retry(next)) {
170 /* If buffer empty break */
171 if (ctx->tmp_len == 0)
173 /* Fall through and process what we have */
177 /* else we retry and add more data to buffer */
185 * We need to scan, a line at a time until we have a valid line if we
188 if (ctx->start && (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)) {
191 } else if (ctx->start) {
192 q = p = (unsigned char *)ctx->tmp;
194 for (j = 0; j < i; j++) {
199 * due to a previous very long line, we need to keep on
200 * scanning for a '\n' before we even start looking for
201 * base64 encoded stuff.
209 k = EVP_DecodeUpdate(ctx->base64,
210 (unsigned char *)ctx->buf,
212 if ((k <= 0) && (num == 0) && (ctx->start))
213 EVP_DecodeInit(ctx->base64);
215 if (p != (unsigned char *)
217 i -= (p - (unsigned char *)
219 for (x = 0; x < i; x++)
222 EVP_DecodeInit(ctx->base64);
229 /* we fell off the end without starting */
230 if ((j == i) && (num == 0)) {
232 * Is this is one long chunk?, if so, keep on reading until a
235 if (p == (unsigned char *)&(ctx->tmp[0])) {
236 /* Check buffer full */
237 if (i == B64_BLOCK_SIZE) {
241 } else if (p != q) { /* finished on a '\n' */
243 for (ii = 0; ii < n; ii++)
244 ctx->tmp[ii] = p[ii];
247 /* else finished on a '\n' */
252 } else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0)) {
254 * If buffer isn't full and we can retry then restart to read in
260 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL) {
263 jj = i & ~3; /* process per 4 */
264 z = EVP_DecodeBlock((unsigned char *)ctx->buf,
265 (unsigned char *)ctx->tmp, jj);
267 if (ctx->tmp[jj - 1] == '=') {
269 if (ctx->tmp[jj - 2] == '=')
274 * z is now number of output bytes and jj is the number consumed
277 memmove(ctx->tmp, &ctx->tmp[jj], i - jj);
278 ctx->tmp_len = i - jj;
286 i = EVP_DecodeUpdate(ctx->base64,
287 (unsigned char *)ctx->buf, &ctx->buf_len,
288 (unsigned char *)ctx->tmp, i);
298 if (ctx->buf_len <= outl)
303 memcpy(out, ctx->buf, i);
306 if (ctx->buf_off == ctx->buf_len) {
313 /* BIO_clear_retry_flags(b); */
314 BIO_copy_next_retry(b);
315 return ((ret == 0) ? ret_code : ret);
318 static int b64_write(BIO *b, const char *in, int inl)
326 ctx = (BIO_B64_CTX *)BIO_get_data(b);
328 if ((ctx == NULL) || (next == NULL))
331 BIO_clear_retry_flags(b);
333 if (ctx->encode != B64_ENCODE) {
334 ctx->encode = B64_ENCODE;
338 EVP_EncodeInit(ctx->base64);
341 OPENSSL_assert(ctx->buf_off < (int)sizeof(ctx->buf));
342 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
343 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
344 n = ctx->buf_len - ctx->buf_off;
346 i = BIO_write(next, &(ctx->buf[ctx->buf_off]), n);
348 BIO_copy_next_retry(b);
351 OPENSSL_assert(i <= n);
353 OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
354 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
357 /* at this point all pending data has been written */
361 if ((in == NULL) || (inl <= 0))
365 n = (inl > B64_BLOCK_SIZE) ? B64_BLOCK_SIZE : inl;
367 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL) {
368 if (ctx->tmp_len > 0) {
369 OPENSSL_assert(ctx->tmp_len <= 3);
370 n = 3 - ctx->tmp_len;
372 * There's a theoretical possibility for this
376 memcpy(&(ctx->tmp[ctx->tmp_len]), in, n);
379 if (ctx->tmp_len < 3)
382 EVP_EncodeBlock((unsigned char *)ctx->buf,
383 (unsigned char *)ctx->tmp, ctx->tmp_len);
384 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
385 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
387 * Since we're now done using the temporary buffer, the
388 * length should be 0'd
393 memcpy(ctx->tmp, in, n);
400 EVP_EncodeBlock((unsigned char *)ctx->buf,
401 (const unsigned char *)in, n);
402 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
403 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
407 if (!EVP_EncodeUpdate(ctx->base64,
408 (unsigned char *)ctx->buf, &ctx->buf_len,
409 (unsigned char *)in, n))
410 return ((ret == 0) ? -1 : ret);
411 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
412 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
421 i = BIO_write(next, &(ctx->buf[ctx->buf_off]), n);
423 BIO_copy_next_retry(b);
424 return ((ret == 0) ? i : ret);
426 OPENSSL_assert(i <= n);
429 OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
430 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
438 static long b64_ctrl(BIO *b, int cmd, long num, void *ptr)
445 ctx = (BIO_B64_CTX *)BIO_get_data(b);
447 if ((ctx == NULL) || (next == NULL))
454 ctx->encode = B64_NONE;
455 ret = BIO_ctrl(next, cmd, num, ptr);
457 case BIO_CTRL_EOF: /* More to read */
461 ret = BIO_ctrl(next, cmd, num, ptr);
463 case BIO_CTRL_WPENDING: /* More to write in buffer */
464 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
465 ret = ctx->buf_len - ctx->buf_off;
466 if ((ret == 0) && (ctx->encode != B64_NONE)
467 && (EVP_ENCODE_CTX_num(ctx->base64) != 0))
470 ret = BIO_ctrl(next, cmd, num, ptr);
472 case BIO_CTRL_PENDING: /* More to read in buffer */
473 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
474 ret = ctx->buf_len - ctx->buf_off;
476 ret = BIO_ctrl(next, cmd, num, ptr);
479 /* do a final write */
481 while (ctx->buf_len != ctx->buf_off) {
482 i = b64_write(b, NULL, 0);
486 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL) {
487 if (ctx->tmp_len != 0) {
488 ctx->buf_len = EVP_EncodeBlock((unsigned char *)ctx->buf,
489 (unsigned char *)ctx->tmp,
495 } else if (ctx->encode != B64_NONE
496 && EVP_ENCODE_CTX_num(ctx->base64) != 0) {
498 EVP_EncodeFinal(ctx->base64,
499 (unsigned char *)ctx->buf, &(ctx->buf_len));
500 /* push out the bytes */
503 /* Finally flush the underlying BIO */
504 ret = BIO_ctrl(next, cmd, num, ptr);
507 case BIO_C_DO_STATE_MACHINE:
508 BIO_clear_retry_flags(b);
509 ret = BIO_ctrl(next, cmd, num, ptr);
510 BIO_copy_next_retry(b);
519 ret = BIO_ctrl(next, cmd, num, ptr);
525 static long b64_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
528 BIO *next = BIO_next(b);
534 ret = BIO_callback_ctrl(next, cmd, fp);
540 static int b64_puts(BIO *b, const char *str)
542 return b64_write(b, str, strlen(str));