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/evp.h>
16 static unsigned char conv_ascii2bin(unsigned char a);
17 #ifndef CHARSET_EBCDIC
18 # define conv_bin2ascii(a) (data_bin2ascii[(a)&0x3f])
21 * We assume that PEM encoded files are EBCDIC files (i.e., printable text
22 * files). Convert them here while decoding. When encoding, output is EBCDIC
23 * (text) format again. (No need for conversion in the conv_bin2ascii macro,
24 * as the underlying textstring data_bin2ascii[] is already EBCDIC)
26 # define conv_bin2ascii(a) (data_bin2ascii[(a)&0x3f])
32 * left over chars are set to =
37 #define BIN_PER_LINE (64/4*3)
38 #define CHUNKS_PER_LINE (64/4)
39 #define CHAR_PER_LINE (64+1)
41 static const unsigned char data_bin2ascii[65] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ\
42 abcdefghijklmnopqrstuvwxyz0123456789+/";
46 * 0xF1 is ignore but next needs to be 0xF0 (for \r\n processing).
48 * 0xE0 is ignore at start of line.
56 #define B64_ERROR 0xFF
57 #define B64_NOT_BASE64(a) (((a)|0x13) == 0xF3)
58 #define B64_BASE64(a) (!B64_NOT_BASE64(a))
60 static const unsigned char data_ascii2bin[128] = {
61 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
62 0xFF, 0xE0, 0xF0, 0xFF, 0xFF, 0xF1, 0xFF, 0xFF,
63 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
64 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
65 0xE0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
66 0xFF, 0xFF, 0xFF, 0x3E, 0xFF, 0xF2, 0xFF, 0x3F,
67 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B,
68 0x3C, 0x3D, 0xFF, 0xFF, 0xFF, 0x00, 0xFF, 0xFF,
69 0xFF, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
70 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E,
71 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16,
72 0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
73 0xFF, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20,
74 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
75 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30,
76 0x31, 0x32, 0x33, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
79 #ifndef CHARSET_EBCDIC
80 static unsigned char conv_ascii2bin(unsigned char a)
84 return data_ascii2bin[a];
87 static unsigned char conv_ascii2bin(unsigned char a)
92 return data_ascii2bin[a];
96 EVP_ENCODE_CTX *EVP_ENCODE_CTX_new(void)
98 return OPENSSL_zalloc(sizeof(EVP_ENCODE_CTX));
101 void EVP_ENCODE_CTX_free(EVP_ENCODE_CTX *ctx)
105 int EVP_ENCODE_CTX_num(EVP_ENCODE_CTX *ctx)
110 void EVP_EncodeInit(EVP_ENCODE_CTX *ctx)
117 int EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl,
118 const unsigned char *in, int inl)
126 OPENSSL_assert(ctx->length <= (int)sizeof(ctx->enc_data));
127 if (ctx->length - ctx->num > inl) {
128 memcpy(&(ctx->enc_data[ctx->num]), in, inl);
133 i = ctx->length - ctx->num;
134 memcpy(&(ctx->enc_data[ctx->num]), in, i);
137 j = EVP_EncodeBlock(out, ctx->enc_data, ctx->length);
144 while (inl >= ctx->length && total <= INT_MAX) {
145 j = EVP_EncodeBlock(out, in, ctx->length);
153 if (total > INT_MAX) {
154 /* Too much output data! */
159 memcpy(&(ctx->enc_data[0]), in, inl);
166 void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl)
168 unsigned int ret = 0;
171 ret = EVP_EncodeBlock(out, ctx->enc_data, ctx->num);
179 int EVP_EncodeBlock(unsigned char *t, const unsigned char *f, int dlen)
184 for (i = dlen; i > 0; i -= 3) {
186 l = (((unsigned long)f[0]) << 16L) |
187 (((unsigned long)f[1]) << 8L) | f[2];
188 *(t++) = conv_bin2ascii(l >> 18L);
189 *(t++) = conv_bin2ascii(l >> 12L);
190 *(t++) = conv_bin2ascii(l >> 6L);
191 *(t++) = conv_bin2ascii(l);
193 l = ((unsigned long)f[0]) << 16L;
195 l |= ((unsigned long)f[1] << 8L);
197 *(t++) = conv_bin2ascii(l >> 18L);
198 *(t++) = conv_bin2ascii(l >> 12L);
199 *(t++) = (i == 1) ? '=' : conv_bin2ascii(l >> 6L);
210 void EVP_DecodeInit(EVP_ENCODE_CTX *ctx)
212 /* Only ctx->num is used during decoding. */
224 * Note: even though EVP_DecodeUpdate attempts to detect and report end of
225 * content, the context doesn't currently remember it and will accept more data
226 * in the next call. Therefore, the caller is responsible for checking and
227 * rejecting a 0 return value in the middle of content.
229 * Note: even though EVP_DecodeUpdate has historically tried to detect end of
230 * content based on line length, this has never worked properly. Therefore,
231 * we now return 0 when one of the following is true:
232 * - Padding or B64_EOF was detected and the last block is complete.
233 * - Input has zero-length.
235 * - Invalid characters are detected.
236 * - There is extra trailing padding, or data after padding.
237 * - B64_EOF is detected after an incomplete base64 block.
239 int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl,
240 const unsigned char *in, int inl)
242 int seof = 0, eof = 0, rv = -1, ret = 0, i, v, tmp, n, decoded_len;
248 if (n > 0 && d[n - 1] == '=') {
250 if (n > 1 && d[n - 2] == '=')
254 /* Legacy behaviour: an empty input chunk signals end of input. */
260 for (i = 0; i < inl; i++) {
262 v = conv_ascii2bin(tmp);
263 if (v == B64_ERROR) {
270 } else if (eof > 0 && B64_BASE64(v)) {
271 /* More data after padding. */
286 /* Only save valid base64 characters. */
290 * We increment n once per loop, and empty the buffer as soon as
291 * we reach 64 characters, so this can only happen if someone's
292 * manually messed with the ctx. Refuse to write any more data.
297 OPENSSL_assert(n < (int)sizeof(ctx->enc_data));
302 decoded_len = EVP_DecodeBlock(out, d, n);
304 if (decoded_len < 0 || eof > decoded_len) {
308 ret += decoded_len - eof;
309 out += decoded_len - eof;
314 * Legacy behaviour: if the current line is a full base64-block (i.e., has
315 * 0 mod 4 base64 characters), it is processed immediately. We keep this
316 * behaviour as applications may not be calling EVP_DecodeFinal properly.
321 decoded_len = EVP_DecodeBlock(out, d, n);
323 if (decoded_len < 0 || eof > decoded_len) {
327 ret += (decoded_len - eof);
329 /* EOF in the middle of a base64 block. */
335 rv = seof || (n == 0 && eof) ? 0 : 1;
337 /* Legacy behaviour. This should probably rather be zeroed on error. */
343 int EVP_DecodeBlock(unsigned char *t, const unsigned char *f, int n)
345 int i, ret = 0, a, b, c, d;
348 /* trim white space from the start of the line. */
349 while ((conv_ascii2bin(*f) == B64_WS) && (n > 0)) {
355 * strip off stuff at the end of the line ascii2bin values B64_WS,
356 * B64_EOLN, B64_EOLN and B64_EOF
358 while ((n > 3) && (B64_NOT_BASE64(conv_ascii2bin(f[n - 1]))))
364 for (i = 0; i < n; i += 4) {
365 a = conv_ascii2bin(*(f++));
366 b = conv_ascii2bin(*(f++));
367 c = conv_ascii2bin(*(f++));
368 d = conv_ascii2bin(*(f++));
369 if ((a & 0x80) || (b & 0x80) || (c & 0x80) || (d & 0x80))
371 l = ((((unsigned long)a) << 18L) |
372 (((unsigned long)b) << 12L) |
373 (((unsigned long)c) << 6L) | (((unsigned long)d)));
374 *(t++) = (unsigned char)(l >> 16L) & 0xff;
375 *(t++) = (unsigned char)(l >> 8L) & 0xff;
376 *(t++) = (unsigned char)(l) & 0xff;
382 int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl)
388 i = EVP_DecodeBlock(out, ctx->enc_data, ctx->num);