From cb3a6310d4fc96596493c4568dfc5d3c926079fa Mon Sep 17 00:00:00 2001 From: Johan Danielsson Date: Mon, 28 May 2001 17:33:41 +0000 Subject: [PATCH] clean up the decode mess somewhat git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@10012 ec53bebd-3082-4978-b11e-865c3cabbd6b --- lib/roken/base64.c | 190 +++++++++++++++++++++------------------------ 1 file changed, 90 insertions(+), 100 deletions(-) diff --git a/lib/roken/base64.c b/lib/roken/base64.c index 0033677f2..187a7c2b6 100644 --- a/lib/roken/base64.c +++ b/lib/roken/base64.c @@ -1,23 +1,23 @@ /* - * Copyright (c) 1995 - 1999 Kungliga Tekniska Högskolan + * Copyright (c) 1995-2001 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. - * + * * 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 above 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. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. - * + * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE @@ -39,108 +39,98 @@ RCSID("$Id$"); #include #include "base64.h" -static char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; +static char base64_chars[] = + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; -static int pos(char c) +static int +pos(char c) { - char *p; - for(p = base64; *p; p++) - if(*p == c) - return p - base64; - return -1; + char *p; + for (p = base64_chars; *p; p++) + if (*p == c) + return p - base64_chars; + return -1; } -int base64_encode(const void *data, int size, char **str) +int +base64_encode(const void *data, int size, char **str) { - char *s, *p; - int i; - int c; - const unsigned char *q; + char *s, *p; + int i; + int c; + const unsigned char *q; - p = s = (char*)malloc(size*4/3+4); - if (p == NULL) - return -1; - q = (const unsigned char*)data; - i=0; - for(i = 0; i < size;){ - c=q[i++]; - c*=256; - if(i < size) - c+=q[i]; - i++; - c*=256; - if(i < size) - c+=q[i]; - i++; - p[0]=base64[(c&0x00fc0000) >> 18]; - p[1]=base64[(c&0x0003f000) >> 12]; - p[2]=base64[(c&0x00000fc0) >> 6]; - p[3]=base64[(c&0x0000003f) >> 0]; - if(i > size) - p[3]='='; - if(i > size+1) - p[2]='='; - p+=4; - } - *p=0; - *str = s; - return strlen(s); + p = s = (char *) malloc(size * 4 / 3 + 4); + if (p == NULL) + return -1; + q = (const unsigned char *) data; + i = 0; + for (i = 0; i < size;) { + c = q[i++]; + c *= 256; + if (i < size) + c += q[i]; + i++; + c *= 256; + if (i < size) + c += q[i]; + i++; + p[0] = base64_chars[(c & 0x00fc0000) >> 18]; + p[1] = base64_chars[(c & 0x0003f000) >> 12]; + p[2] = base64_chars[(c & 0x00000fc0) >> 6]; + p[3] = base64_chars[(c & 0x0000003f) >> 0]; + if (i > size) + p[3] = '='; + if (i > size + 1) + p[2] = '='; + p += 4; + } + *p = 0; + *str = s; + return strlen(s); } -int base64_decode(const char *str, void *data) +#define DECODE_ERROR 0xffffffff + +static unsigned int +token_decode(const char *token) { - const char *p; - unsigned char *q; - int c; - int x; - int done = 0; - q=(unsigned char*)data; - for(p=str; *p && !done; p+=4){ - x = pos(p[0]); - if(x >= 0) - c = x; - else{ - done = 3; - break; + int i; + unsigned int val = 0; + int marker = 0; + if (strlen(token) < 4) + return DECODE_ERROR; + for (i = 0; i < 4; i++) { + val *= 64; + if (token[i] == '=') + marker++; + else if (marker > 0) + return DECODE_ERROR; + else + val += pos(token[i]); } - c*=64; - - x = pos(p[1]); - if(x >= 0) - c += x; - else - return -1; - c*=64; - - if(p[2] == '=') - done++; - else{ - x = pos(p[2]); - if(x >= 0) - c += x; - else - return -1; - } - c*=64; - - if(p[3] == '=') - done++; - else{ - if(done) - return -1; - x = pos(p[3]); - if(x >= 0) - c += x; - else - return -1; - } - if(done < 3) - *q++=(c&0x00ff0000)>>16; - - if(done < 2) - *q++=(c&0x0000ff00)>>8; - if(done < 1) - *q++=(c&0x000000ff)>>0; - } - return q - (unsigned char*)data; + if (marker > 2) + return DECODE_ERROR; + return (marker << 24) | val; +} + +int +base64_decode(const char *str, void *data) +{ + const char *p; + unsigned char *q; + + q = data; + for (p = str; *p && (*p == '=' || strchr(base64_chars, *p)); p += 4) { + unsigned int val = token_decode(p); + unsigned int marker = (val >> 24) & 0xff; + if (val == DECODE_ERROR) + return -1; + *q++ = (val >> 16) & 0xff; + if (marker < 2) + *q++ = (val >> 8) & 0xff; + if (marker < 1) + *q++ = val & 0xff; + } + return q - (unsigned char *) data; }