| /* |
| * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved. |
| * |
| * Licensed under the OpenSSL license (the "License"). You may not use |
| * this file except in compliance with the License. You can obtain a copy |
| * in the file LICENSE in the source distribution or at |
| * https://www.openssl.org/source/license.html |
| */ |
| |
| #include <stdio.h> |
| #include <limits.h> |
| #include "internal/cryptlib.h" |
| #include <openssl/evp.h> |
| #include "evp_local.h" |
| #include "crypto/evp.h" |
| |
| static unsigned char conv_ascii2bin(unsigned char a, |
| const unsigned char *table); |
| static int evp_encodeblock_int(EVP_ENCODE_CTX *ctx, unsigned char *t, |
| const unsigned char *f, int dlen); |
| static int evp_decodeblock_int(EVP_ENCODE_CTX *ctx, unsigned char *t, |
| const unsigned char *f, int n); |
| |
| #ifndef CHARSET_EBCDIC |
| # define conv_bin2ascii(a, table) ((table)[(a)&0x3f]) |
| #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, table) ((table)[(a)&0x3f]) |
| #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] = |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| |
| /* SRP uses a different base64 alphabet */ |
| static const unsigned char srpdata_bin2ascii[65] = |
| "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./"; |
| |
| |
| /*- |
| * 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) |
| #define B64_BASE64(a) (!B64_NOT_BASE64(a)) |
| |
| 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, |
| }; |
| |
| static const unsigned char srpdata_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, 0xFF, 0xFF, 0xF2, 0x3E, 0x3F, |
| 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, |
| 0x08, 0x09, 0xFF, 0xFF, 0xFF, 0x00, 0xFF, 0xFF, |
| 0xFF, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, |
| 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, |
| 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, |
| 0x21, 0x22, 0x23, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, |
| 0xFF, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, |
| 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, |
| 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, |
| 0x3B, 0x3C, 0x3D, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, |
| }; |
| |
| #ifndef CHARSET_EBCDIC |
| static unsigned char conv_ascii2bin(unsigned char a, const unsigned char *table) |
| { |
| if (a & 0x80) |
| return B64_ERROR; |
| return table[a]; |
| } |
| #else |
| static unsigned char conv_ascii2bin(unsigned char a, const unsigned char *table) |
| { |
| a = os_toascii[a]; |
| if (a & 0x80) |
| return B64_ERROR; |
| return table[a]; |
| } |
| #endif |
| |
| EVP_ENCODE_CTX *EVP_ENCODE_CTX_new(void) |
| { |
| return OPENSSL_zalloc(sizeof(EVP_ENCODE_CTX)); |
| } |
| |
| void EVP_ENCODE_CTX_free(EVP_ENCODE_CTX *ctx) |
| { |
| OPENSSL_free(ctx); |
| } |
| |
| int EVP_ENCODE_CTX_copy(EVP_ENCODE_CTX *dctx, EVP_ENCODE_CTX *sctx) |
| { |
| memcpy(dctx, sctx, sizeof(EVP_ENCODE_CTX)); |
| |
| return 1; |
| } |
| |
| int EVP_ENCODE_CTX_num(EVP_ENCODE_CTX *ctx) |
| { |
| return ctx->num; |
| } |
| |
| void evp_encode_ctx_set_flags(EVP_ENCODE_CTX *ctx, unsigned int flags) |
| { |
| ctx->flags = flags; |
| } |
| |
| void EVP_EncodeInit(EVP_ENCODE_CTX *ctx) |
| { |
| ctx->length = 48; |
| ctx->num = 0; |
| ctx->line_num = 0; |
| ctx->flags = 0; |
| } |
| |
| int EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl, |
| const unsigned char *in, int inl) |
| { |
| int i, j; |
| size_t total = 0; |
| |
| *outl = 0; |
| if (inl <= 0) |
| return 0; |
| OPENSSL_assert(ctx->length <= (int)sizeof(ctx->enc_data)); |
| if (ctx->length - ctx->num > inl) { |
| memcpy(&(ctx->enc_data[ctx->num]), in, inl); |
| ctx->num += inl; |
| return 1; |
| } |
| if (ctx->num != 0) { |
| i = ctx->length - ctx->num; |
| memcpy(&(ctx->enc_data[ctx->num]), in, i); |
| in += i; |
| inl -= i; |
| j = evp_encodeblock_int(ctx, out, ctx->enc_data, ctx->length); |
| ctx->num = 0; |
| out += j; |
| total = j; |
| if ((ctx->flags & EVP_ENCODE_CTX_NO_NEWLINES) == 0) { |
| *(out++) = '\n'; |
| total++; |
| } |
| *out = '\0'; |
| } |
| while (inl >= ctx->length && total <= INT_MAX) { |
| j = evp_encodeblock_int(ctx, out, in, ctx->length); |
| in += ctx->length; |
| inl -= ctx->length; |
| out += j; |
| total += j; |
| if ((ctx->flags & EVP_ENCODE_CTX_NO_NEWLINES) == 0) { |
| *(out++) = '\n'; |
| total++; |
| } |
| *out = '\0'; |
| } |
| if (total > INT_MAX) { |
| /* Too much output data! */ |
| *outl = 0; |
| return 0; |
| } |
| if (inl != 0) |
| memcpy(&(ctx->enc_data[0]), in, inl); |
| ctx->num = inl; |
| *outl = total; |
| |
| return 1; |
| } |
| |
| void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl) |
| { |
| unsigned int ret = 0; |
| |
| if (ctx->num != 0) { |
| ret = evp_encodeblock_int(ctx, out, ctx->enc_data, ctx->num); |
| if ((ctx->flags & EVP_ENCODE_CTX_NO_NEWLINES) == 0) |
| out[ret++] = '\n'; |
| out[ret] = '\0'; |
| ctx->num = 0; |
| } |
| *outl = ret; |
| } |
| |
| static int evp_encodeblock_int(EVP_ENCODE_CTX *ctx, unsigned char *t, |
| const unsigned char *f, int dlen) |
| { |
| int i, ret = 0; |
| unsigned long l; |
| const unsigned char *table; |
| |
| if (ctx != NULL && (ctx->flags & EVP_ENCODE_CTX_USE_SRP_ALPHABET) != 0) |
| table = srpdata_bin2ascii; |
| else |
| table = data_bin2ascii; |
| |
| 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, table); |
| *(t++) = conv_bin2ascii(l >> 12L, table); |
| *(t++) = conv_bin2ascii(l >> 6L, table); |
| *(t++) = conv_bin2ascii(l, table); |
| } else { |
| l = ((unsigned long)f[0]) << 16L; |
| if (i == 2) |
| l |= ((unsigned long)f[1] << 8L); |
| |
| *(t++) = conv_bin2ascii(l >> 18L, table); |
| *(t++) = conv_bin2ascii(l >> 12L, table); |
| *(t++) = (i == 1) ? '=' : conv_bin2ascii(l >> 6L, table); |
| *(t++) = '='; |
| } |
| ret += 4; |
| f += 3; |
| } |
| |
| *t = '\0'; |
| return ret; |
| } |
| |
| int EVP_EncodeBlock(unsigned char *t, const unsigned char *f, int dlen) |
| { |
| return evp_encodeblock_int(NULL, t, f, dlen); |
| } |
| |
| void EVP_DecodeInit(EVP_ENCODE_CTX *ctx) |
| { |
| /* Only ctx->num and ctx->flags are used during decoding. */ |
| ctx->num = 0; |
| ctx->length = 0; |
| ctx->line_num = 0; |
| ctx->flags = 0; |
| } |
| |
| /*- |
| * -1 for error |
| * 0 for last line |
| * 1 for full line |
| * |
| * Note: even though EVP_DecodeUpdate attempts to detect and report end of |
| * content, the context doesn't currently remember it and will accept more data |
| * in the next call. Therefore, the caller is responsible for checking and |
| * rejecting a 0 return value in the middle of content. |
| * |
| * Note: even though EVP_DecodeUpdate has historically tried to detect end of |
| * content based on line length, this has never worked properly. Therefore, |
| * we now return 0 when one of the following is true: |
| * - Padding or B64_EOF was detected and the last block is complete. |
| * - Input has zero-length. |
| * -1 is returned if: |
| * - Invalid characters are detected. |
| * - There is extra trailing padding, or data after padding. |
| * - B64_EOF is detected after an incomplete base64 block. |
| */ |
| int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl, |
| const unsigned char *in, int inl) |
| { |
| int seof = 0, eof = 0, rv = -1, ret = 0, i, v, tmp, n, decoded_len; |
| unsigned char *d; |
| const unsigned char *table; |
| |
| n = ctx->num; |
| d = ctx->enc_data; |
| |
| if (n > 0 && d[n - 1] == '=') { |
| eof++; |
| if (n > 1 && d[n - 2] == '=') |
| eof++; |
| } |
| |
| /* Legacy behaviour: an empty input chunk signals end of input. */ |
| if (inl == 0) { |
| rv = 0; |
| goto end; |
| } |
| |
| if ((ctx->flags & EVP_ENCODE_CTX_USE_SRP_ALPHABET) != 0) |
| table = srpdata_ascii2bin; |
| else |
| table = data_ascii2bin; |
| |
| for (i = 0; i < inl; i++) { |
| tmp = *(in++); |
| v = conv_ascii2bin(tmp, table); |
| if (v == B64_ERROR) { |
| rv = -1; |
| goto end; |
| } |
| |
| if (tmp == '=') { |
| eof++; |
| } else if (eof > 0 && B64_BASE64(v)) { |
| /* More data after padding. */ |
| rv = -1; |
| goto end; |
| } |
| |
| if (eof > 2) { |
| rv = -1; |
| goto end; |
| } |
| |
| if (v == B64_EOF) { |
| seof = 1; |
| goto tail; |
| } |
| |
| /* Only save valid base64 characters. */ |
| if (B64_BASE64(v)) { |
| if (n >= 64) { |
| /* |
| * We increment n once per loop, and empty the buffer as soon as |
| * we reach 64 characters, so this can only happen if someone's |
| * manually messed with the ctx. Refuse to write any more data. |
| */ |
| rv = -1; |
| goto end; |
| } |
| OPENSSL_assert(n < (int)sizeof(ctx->enc_data)); |
| d[n++] = tmp; |
| } |
| |
| if (n == 64) { |
| decoded_len = evp_decodeblock_int(ctx, out, d, n); |
| n = 0; |
| if (decoded_len < 0 || eof > decoded_len) { |
| rv = -1; |
| goto end; |
| } |
| ret += decoded_len - eof; |
| out += decoded_len - eof; |
| } |
| } |
| |
| /* |
| * Legacy behaviour: if the current line is a full base64-block (i.e., has |
| * 0 mod 4 base64 characters), it is processed immediately. We keep this |
| * behaviour as applications may not be calling EVP_DecodeFinal properly. |
| */ |
| tail: |
| if (n > 0) { |
| if ((n & 3) == 0) { |
| decoded_len = evp_decodeblock_int(ctx, out, d, n); |
| n = 0; |
| if (decoded_len < 0 || eof > decoded_len) { |
| rv = -1; |
| goto end; |
| } |
| ret += (decoded_len - eof); |
| } else if (seof) { |
| /* EOF in the middle of a base64 block. */ |
| rv = -1; |
| goto end; |
| } |
| } |
| |
| rv = seof || (n == 0 && eof) ? 0 : 1; |
| end: |
| /* Legacy behaviour. This should probably rather be zeroed on error. */ |
| *outl = ret; |
| ctx->num = n; |
| return rv; |
| } |
| |
| static int evp_decodeblock_int(EVP_ENCODE_CTX *ctx, unsigned char *t, |
| const unsigned char *f, int n) |
| { |
| int i, ret = 0, a, b, c, d; |
| unsigned long l; |
| const unsigned char *table; |
| |
| if (ctx != NULL && (ctx->flags & EVP_ENCODE_CTX_USE_SRP_ALPHABET) != 0) |
| table = srpdata_ascii2bin; |
| else |
| table = data_ascii2bin; |
| |
| /* trim white space from the start of the line. */ |
| while ((n > 0) && (conv_ascii2bin(*f, table) == B64_WS)) { |
| 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], table)))) |
| n--; |
| |
| if (n % 4 != 0) |
| return -1; |
| |
| for (i = 0; i < n; i += 4) { |
| a = conv_ascii2bin(*(f++), table); |
| b = conv_ascii2bin(*(f++), table); |
| c = conv_ascii2bin(*(f++), table); |
| d = conv_ascii2bin(*(f++), table); |
| 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_DecodeBlock(unsigned char *t, const unsigned char *f, int n) |
| { |
| return evp_decodeblock_int(NULL, t, f, n); |
| } |
| |
| int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl) |
| { |
| int i; |
| |
| *outl = 0; |
| if (ctx->num != 0) { |
| i = evp_decodeblock_int(ctx, out, ctx->enc_data, ctx->num); |
| if (i < 0) |
| return -1; |
| ctx->num = 0; |
| *outl = i; |
| return 1; |
| } else |
| return 1; |
| } |