/* * Copyright 1995-2018 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 #include #include "internal/cryptlib.h" #include #include "crypto/evp.h" #include "evp_local.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 ((conv_ascii2bin(*f, table) == 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], 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; }