openssl/crypto/evp/encode.c
Matt Caswell b86d7dca69 Sanity check EVP_EncodeUpdate buffer len
There was already a sanity check to ensure the passed buffer length is not
zero. Extend this to ensure that it also not negative. Thanks to Kevin
Wojtysiak (Int3 Solutions) and Paramjot Oberoi (Int3 Solutions) for
reporting this issue.

Reviewed-by: Andy Polyakov <appro@openssl.org>
2015-04-30 23:12:39 +01:00

420 lines
13 KiB
C

/* crypto/evp/encode.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/evp.h>
#ifndef CHARSET_EBCDIC
# define conv_bin2ascii(a) (data_bin2ascii[(a)&0x3f])
# define conv_ascii2bin(a) (data_ascii2bin[(a)&0x7f])
#else
/*
* We assume that PEM encoded files are EBCDIC files (i.e., printable text
* files). Convert them here while decoding. When encoding, output is EBCDIC
* (text) format again. (No need for conversion in the conv_bin2ascii macro,
* as the underlying textstring data_bin2ascii[] is already EBCDIC)
*/
# define conv_bin2ascii(a) (data_bin2ascii[(a)&0x3f])
# define conv_ascii2bin(a) (data_ascii2bin[os_toascii[a]&0x7f])
#endif
/*-
* 64 char lines
* pad input with 0
* left over chars are set to =
* 1 byte => xx==
* 2 bytes => xxx=
* 3 bytes => xxxx
*/
#define BIN_PER_LINE (64/4*3)
#define CHUNKS_PER_LINE (64/4)
#define CHAR_PER_LINE (64+1)
static const unsigned char data_bin2ascii[65] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ\
abcdefghijklmnopqrstuvwxyz0123456789+/";
/*-
* 0xF0 is a EOLN
* 0xF1 is ignore but next needs to be 0xF0 (for \r\n processing).
* 0xF2 is EOF
* 0xE0 is ignore at start of line.
* 0xFF is error
*/
#define B64_EOLN 0xF0
#define B64_CR 0xF1
#define B64_EOF 0xF2
#define B64_WS 0xE0
#define B64_ERROR 0xFF
#define B64_NOT_BASE64(a) (((a)|0x13) == 0xF3)
static const unsigned char data_ascii2bin[128] = {
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xE0, 0xF0, 0xFF, 0xFF, 0xF1, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xE0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0x3E, 0xFF, 0xF2, 0xFF, 0x3F,
0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B,
0x3C, 0x3D, 0xFF, 0xFF, 0xFF, 0x00, 0xFF, 0xFF,
0xFF, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E,
0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16,
0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20,
0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30,
0x31, 0x32, 0x33, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
};
void EVP_EncodeInit(EVP_ENCODE_CTX *ctx)
{
ctx->length = 48;
ctx->num = 0;
ctx->line_num = 0;
}
void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
int i, j;
unsigned int total = 0;
*outl = 0;
if (inl <= 0)
return;
OPENSSL_assert(ctx->length <= (int)sizeof(ctx->enc_data));
if ((ctx->num + inl) < ctx->length) {
memcpy(&(ctx->enc_data[ctx->num]), in, inl);
ctx->num += inl;
return;
}
if (ctx->num != 0) {
i = ctx->length - ctx->num;
memcpy(&(ctx->enc_data[ctx->num]), in, i);
in += i;
inl -= i;
j = EVP_EncodeBlock(out, ctx->enc_data, ctx->length);
ctx->num = 0;
out += j;
*(out++) = '\n';
*out = '\0';
total = j + 1;
}
while (inl >= ctx->length) {
j = EVP_EncodeBlock(out, in, ctx->length);
in += ctx->length;
inl -= ctx->length;
out += j;
*(out++) = '\n';
*out = '\0';
total += j + 1;
}
if (inl != 0)
memcpy(&(ctx->enc_data[0]), in, inl);
ctx->num = inl;
*outl = total;
}
void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl)
{
unsigned int ret = 0;
if (ctx->num != 0) {
ret = EVP_EncodeBlock(out, ctx->enc_data, ctx->num);
out[ret++] = '\n';
out[ret] = '\0';
ctx->num = 0;
}
*outl = ret;
}
int EVP_EncodeBlock(unsigned char *t, const unsigned char *f, int dlen)
{
int i, ret = 0;
unsigned long l;
for (i = dlen; i > 0; i -= 3) {
if (i >= 3) {
l = (((unsigned long)f[0]) << 16L) |
(((unsigned long)f[1]) << 8L) | f[2];
*(t++) = conv_bin2ascii(l >> 18L);
*(t++) = conv_bin2ascii(l >> 12L);
*(t++) = conv_bin2ascii(l >> 6L);
*(t++) = conv_bin2ascii(l);
} else {
l = ((unsigned long)f[0]) << 16L;
if (i == 2)
l |= ((unsigned long)f[1] << 8L);
*(t++) = conv_bin2ascii(l >> 18L);
*(t++) = conv_bin2ascii(l >> 12L);
*(t++) = (i == 1) ? '=' : conv_bin2ascii(l >> 6L);
*(t++) = '=';
}
ret += 4;
f += 3;
}
*t = '\0';
return (ret);
}
void EVP_DecodeInit(EVP_ENCODE_CTX *ctx)
{
ctx->length = 30;
ctx->num = 0;
ctx->line_num = 0;
ctx->expect_nl = 0;
}
/*-
* -1 for error
* 0 for last line
* 1 for full line
*/
int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
int seof = -1, eof = 0, rv = -1, ret = 0, i, v, tmp, n, ln, exp_nl;
unsigned char *d;
n = ctx->num;
d = ctx->enc_data;
ln = ctx->line_num;
exp_nl = ctx->expect_nl;
/* last line of input. */
if ((inl == 0) || ((n == 0) && (conv_ascii2bin(in[0]) == B64_EOF))) {
rv = 0;
goto end;
}
/* We parse the input data */
for (i = 0; i < inl; i++) {
/* If the current line is > 80 characters, scream a lot */
if (ln >= 80) {
rv = -1;
goto end;
}
/* Get char and put it into the buffer */
tmp = *(in++);
v = conv_ascii2bin(tmp);
/* only save the good data :-) */
if (!B64_NOT_BASE64(v)) {
OPENSSL_assert(n < (int)sizeof(ctx->enc_data));
d[n++] = tmp;
ln++;
} else if (v == B64_ERROR) {
rv = -1;
goto end;
}
/*
* have we seen a '=' which is 'definitly' the last input line. seof
* will point to the character that holds it. and eof will hold how
* many characters to chop off.
*/
if (tmp == '=') {
if (seof == -1)
seof = n;
eof++;
}
if (v == B64_CR) {
ln = 0;
if (exp_nl)
continue;
}
/* eoln */
if (v == B64_EOLN) {
ln = 0;
if (exp_nl) {
exp_nl = 0;
continue;
}
}
exp_nl = 0;
/*
* If we are at the end of input and it looks like a line, process
* it.
*/
if (((i + 1) == inl) && (((n & 3) == 0) || eof)) {
v = B64_EOF;
/*
* In case things were given us in really small records (so two
* '=' were given in separate updates), eof may contain the
* incorrect number of ending bytes to skip, so let's redo the
* count
*/
eof = 0;
if (d[n - 1] == '=')
eof++;
if (d[n - 2] == '=')
eof++;
/* There will never be more than two '=' */
}
if ((v == B64_EOF && (n & 3) == 0) || (n >= 64)) {
/*
* This is needed to work correctly on 64 byte input lines. We
* process the line and then need to accept the '\n'
*/
if ((v != B64_EOF) && (n >= 64))
exp_nl = 1;
if (n > 0) {
v = EVP_DecodeBlock(out, d, n);
n = 0;
if (v < 0) {
rv = 0;
goto end;
}
if (eof > v) {
rv = -1;
goto end;
}
ret += (v - eof);
} else {
eof = 1;
v = 0;
}
/*
* This is the case where we have had a short but valid input
* line
*/
if ((v < ctx->length) && eof) {
rv = 0;
goto end;
} else
ctx->length = v;
if (seof >= 0) {
rv = 0;
goto end;
}
out += v;
}
}
rv = 1;
end:
*outl = ret;
ctx->num = n;
ctx->line_num = ln;
ctx->expect_nl = exp_nl;
return (rv);
}
int EVP_DecodeBlock(unsigned char *t, const unsigned char *f, int n)
{
int i, ret = 0, a, b, c, d;
unsigned long l;
/* trim white space from the start of the line. */
while ((conv_ascii2bin(*f) == B64_WS) && (n > 0)) {
f++;
n--;
}
/*
* strip off stuff at the end of the line ascii2bin values B64_WS,
* B64_EOLN, B64_EOLN and B64_EOF
*/
while ((n > 3) && (B64_NOT_BASE64(conv_ascii2bin(f[n - 1]))))
n--;
if (n % 4 != 0)
return (-1);
for (i = 0; i < n; i += 4) {
a = conv_ascii2bin(*(f++));
b = conv_ascii2bin(*(f++));
c = conv_ascii2bin(*(f++));
d = conv_ascii2bin(*(f++));
if ((a & 0x80) || (b & 0x80) || (c & 0x80) || (d & 0x80))
return (-1);
l = ((((unsigned long)a) << 18L) |
(((unsigned long)b) << 12L) |
(((unsigned long)c) << 6L) | (((unsigned long)d)));
*(t++) = (unsigned char)(l >> 16L) & 0xff;
*(t++) = (unsigned char)(l >> 8L) & 0xff;
*(t++) = (unsigned char)(l) & 0xff;
ret += 3;
}
return (ret);
}
int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl)
{
int i;
*outl = 0;
if (ctx->num != 0) {
i = EVP_DecodeBlock(out, ctx->enc_data, ctx->num);
if (i < 0)
return (-1);
ctx->num = 0;
*outl = i;
return (1);
} else
return (1);
}