1  | 
     | 
     | 
    /*	$OpenBSD: base64.c,v 1.8 2015/01/16 16:48:51 deraadt Exp $	*/  | 
    
    
    2  | 
     | 
     | 
     | 
    
    
    3  | 
     | 
     | 
    /*  | 
    
    
    4  | 
     | 
     | 
     * Copyright (c) 1996 by Internet Software Consortium.  | 
    
    
    5  | 
     | 
     | 
     *  | 
    
    
    6  | 
     | 
     | 
     * Permission to use, copy, modify, and distribute this software for any  | 
    
    
    7  | 
     | 
     | 
     * purpose with or without fee is hereby granted, provided that the above  | 
    
    
    8  | 
     | 
     | 
     * copyright notice and this permission notice appear in all copies.  | 
    
    
    9  | 
     | 
     | 
     *  | 
    
    
    10  | 
     | 
     | 
     * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS  | 
    
    
    11  | 
     | 
     | 
     * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES  | 
    
    
    12  | 
     | 
     | 
     * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE  | 
    
    
    13  | 
     | 
     | 
     * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL  | 
    
    
    14  | 
     | 
     | 
     * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR  | 
    
    
    15  | 
     | 
     | 
     * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS  | 
    
    
    16  | 
     | 
     | 
     * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS  | 
    
    
    17  | 
     | 
     | 
     * SOFTWARE.  | 
    
    
    18  | 
     | 
     | 
     */  | 
    
    
    19  | 
     | 
     | 
     | 
    
    
    20  | 
     | 
     | 
    /*  | 
    
    
    21  | 
     | 
     | 
     * Portions Copyright (c) 1995 by International Business Machines, Inc.  | 
    
    
    22  | 
     | 
     | 
     *  | 
    
    
    23  | 
     | 
     | 
     * International Business Machines, Inc. (hereinafter called IBM) grants  | 
    
    
    24  | 
     | 
     | 
     * permission under its copyrights to use, copy, modify, and distribute this  | 
    
    
    25  | 
     | 
     | 
     * Software with or without fee, provided that the above copyright notice and  | 
    
    
    26  | 
     | 
     | 
     * all paragraphs of this notice appear in all copies, and that the name of IBM  | 
    
    
    27  | 
     | 
     | 
     * not be used in connection with the marketing of any product incorporating  | 
    
    
    28  | 
     | 
     | 
     * the Software or modifications thereof, without specific, written prior  | 
    
    
    29  | 
     | 
     | 
     * permission.  | 
    
    
    30  | 
     | 
     | 
     *  | 
    
    
    31  | 
     | 
     | 
     * To the extent it has a right to do so, IBM grants an immunity from suit  | 
    
    
    32  | 
     | 
     | 
     * under its patents, if any, for the use, sale or manufacture of products to  | 
    
    
    33  | 
     | 
     | 
     * the extent that such products are used for performing Domain Name System  | 
    
    
    34  | 
     | 
     | 
     * dynamic updates in TCP/IP networks by means of the Software.  No immunity is  | 
    
    
    35  | 
     | 
     | 
     * granted for any product per se or for any other function of any product.  | 
    
    
    36  | 
     | 
     | 
     *  | 
    
    
    37  | 
     | 
     | 
     * THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES,  | 
    
    
    38  | 
     | 
     | 
     * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A  | 
    
    
    39  | 
     | 
     | 
     * PARTICULAR PURPOSE.  IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL,  | 
    
    
    40  | 
     | 
     | 
     * DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING  | 
    
    
    41  | 
     | 
     | 
     * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN  | 
    
    
    42  | 
     | 
     | 
     * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES.  | 
    
    
    43  | 
     | 
     | 
     */  | 
    
    
    44  | 
     | 
     | 
     | 
    
    
    45  | 
     | 
     | 
    #include <sys/types.h>  | 
    
    
    46  | 
     | 
     | 
    #include <sys/socket.h>  | 
    
    
    47  | 
     | 
     | 
    #include <netinet/in.h>  | 
    
    
    48  | 
     | 
     | 
    #include <arpa/inet.h>  | 
    
    
    49  | 
     | 
     | 
    #include <arpa/nameser.h>  | 
    
    
    50  | 
     | 
     | 
     | 
    
    
    51  | 
     | 
     | 
    #include <ctype.h>  | 
    
    
    52  | 
     | 
     | 
    #include <resolv.h>  | 
    
    
    53  | 
     | 
     | 
    #include <stdio.h>  | 
    
    
    54  | 
     | 
     | 
     | 
    
    
    55  | 
     | 
     | 
    #include <stdlib.h>  | 
    
    
    56  | 
     | 
     | 
    #include <string.h>  | 
    
    
    57  | 
     | 
     | 
     | 
    
    
    58  | 
     | 
     | 
    static const char Base64[] =  | 
    
    
    59  | 
     | 
     | 
    	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";  | 
    
    
    60  | 
     | 
     | 
    static const char Pad64 = '=';  | 
    
    
    61  | 
     | 
     | 
     | 
    
    
    62  | 
     | 
     | 
    /* (From RFC1521 and draft-ietf-dnssec-secext-03.txt)  | 
    
    
    63  | 
     | 
     | 
       The following encoding technique is taken from RFC 1521 by Borenstein  | 
    
    
    64  | 
     | 
     | 
       and Freed.  It is reproduced here in a slightly edited form for  | 
    
    
    65  | 
     | 
     | 
       convenience.  | 
    
    
    66  | 
     | 
     | 
     | 
    
    
    67  | 
     | 
     | 
       A 65-character subset of US-ASCII is used, enabling 6 bits to be  | 
    
    
    68  | 
     | 
     | 
       represented per printable character. (The extra 65th character, "=",  | 
    
    
    69  | 
     | 
     | 
       is used to signify a special processing function.)  | 
    
    
    70  | 
     | 
     | 
     | 
    
    
    71  | 
     | 
     | 
       The encoding process represents 24-bit groups of input bits as output  | 
    
    
    72  | 
     | 
     | 
       strings of 4 encoded characters. Proceeding from left to right, a  | 
    
    
    73  | 
     | 
     | 
       24-bit input group is formed by concatenating 3 8-bit input groups.  | 
    
    
    74  | 
     | 
     | 
       These 24 bits are then treated as 4 concatenated 6-bit groups, each  | 
    
    
    75  | 
     | 
     | 
       of which is translated into a single digit in the base64 alphabet.  | 
    
    
    76  | 
     | 
     | 
     | 
    
    
    77  | 
     | 
     | 
       Each 6-bit group is used as an index into an array of 64 printable  | 
    
    
    78  | 
     | 
     | 
       characters. The character referenced by the index is placed in the  | 
    
    
    79  | 
     | 
     | 
       output string.  | 
    
    
    80  | 
     | 
     | 
     | 
    
    
    81  | 
     | 
     | 
                             Table 1: The Base64 Alphabet  | 
    
    
    82  | 
     | 
     | 
     | 
    
    
    83  | 
     | 
     | 
          Value Encoding  Value Encoding  Value Encoding  Value Encoding  | 
    
    
    84  | 
     | 
     | 
              0 A            17 R            34 i            51 z  | 
    
    
    85  | 
     | 
     | 
              1 B            18 S            35 j            52 0  | 
    
    
    86  | 
     | 
     | 
              2 C            19 T            36 k            53 1  | 
    
    
    87  | 
     | 
     | 
              3 D            20 U            37 l            54 2  | 
    
    
    88  | 
     | 
     | 
              4 E            21 V            38 m            55 3  | 
    
    
    89  | 
     | 
     | 
              5 F            22 W            39 n            56 4  | 
    
    
    90  | 
     | 
     | 
              6 G            23 X            40 o            57 5  | 
    
    
    91  | 
     | 
     | 
              7 H            24 Y            41 p            58 6  | 
    
    
    92  | 
     | 
     | 
              8 I            25 Z            42 q            59 7  | 
    
    
    93  | 
     | 
     | 
              9 J            26 a            43 r            60 8  | 
    
    
    94  | 
     | 
     | 
             10 K            27 b            44 s            61 9  | 
    
    
    95  | 
     | 
     | 
             11 L            28 c            45 t            62 +  | 
    
    
    96  | 
     | 
     | 
             12 M            29 d            46 u            63 /  | 
    
    
    97  | 
     | 
     | 
             13 N            30 e            47 v  | 
    
    
    98  | 
     | 
     | 
             14 O            31 f            48 w         (pad) =  | 
    
    
    99  | 
     | 
     | 
             15 P            32 g            49 x  | 
    
    
    100  | 
     | 
     | 
             16 Q            33 h            50 y  | 
    
    
    101  | 
     | 
     | 
     | 
    
    
    102  | 
     | 
     | 
       Special processing is performed if fewer than 24 bits are available  | 
    
    
    103  | 
     | 
     | 
       at the end of the data being encoded.  A full encoding quantum is  | 
    
    
    104  | 
     | 
     | 
       always completed at the end of a quantity.  When fewer than 24 input  | 
    
    
    105  | 
     | 
     | 
       bits are available in an input group, zero bits are added (on the  | 
    
    
    106  | 
     | 
     | 
       right) to form an integral number of 6-bit groups.  Padding at the  | 
    
    
    107  | 
     | 
     | 
       end of the data is performed using the '=' character.  | 
    
    
    108  | 
     | 
     | 
     | 
    
    
    109  | 
     | 
     | 
       Since all base64 input is an integral number of octets, only the  | 
    
    
    110  | 
     | 
     | 
             -------------------------------------------------  | 
    
    
    111  | 
     | 
     | 
       following cases can arise:  | 
    
    
    112  | 
     | 
     | 
     | 
    
    
    113  | 
     | 
     | 
           (1) the final quantum of encoding input is an integral  | 
    
    
    114  | 
     | 
     | 
               multiple of 24 bits; here, the final unit of encoded  | 
    
    
    115  | 
     | 
     | 
    	   output will be an integral multiple of 4 characters  | 
    
    
    116  | 
     | 
     | 
    	   with no "=" padding,  | 
    
    
    117  | 
     | 
     | 
           (2) the final quantum of encoding input is exactly 8 bits;  | 
    
    
    118  | 
     | 
     | 
               here, the final unit of encoded output will be two  | 
    
    
    119  | 
     | 
     | 
    	   characters followed by two "=" padding characters, or  | 
    
    
    120  | 
     | 
     | 
           (3) the final quantum of encoding input is exactly 16 bits;  | 
    
    
    121  | 
     | 
     | 
               here, the final unit of encoded output will be three  | 
    
    
    122  | 
     | 
     | 
    	   characters followed by one "=" padding character.  | 
    
    
    123  | 
     | 
     | 
       */  | 
    
    
    124  | 
     | 
     | 
     | 
    
    
    125  | 
     | 
     | 
    int  | 
    
    
    126  | 
     | 
     | 
    b64_ntop(src, srclength, target, targsize)  | 
    
    
    127  | 
     | 
     | 
    	u_char const *src;  | 
    
    
    128  | 
     | 
     | 
    	size_t srclength;  | 
    
    
    129  | 
     | 
     | 
    	char *target;  | 
    
    
    130  | 
     | 
     | 
    	size_t targsize;  | 
    
    
    131  | 
     | 
     | 
    { | 
    
    
    132  | 
     | 
     | 
    	size_t datalength = 0;  | 
    
    
    133  | 
     | 
     | 
    	u_char input[3];  | 
    
    
    134  | 
     | 
     | 
    	u_char output[4];  | 
    
    
    135  | 
     | 
     | 
    	int i;  | 
    
    
    136  | 
     | 
     | 
     | 
    
    
    137  | 
     | 
     | 
    	while (2 < srclength) { | 
    
    
    138  | 
     | 
     | 
    		input[0] = *src++;  | 
    
    
    139  | 
     | 
     | 
    		input[1] = *src++;  | 
    
    
    140  | 
     | 
     | 
    		input[2] = *src++;  | 
    
    
    141  | 
     | 
     | 
    		srclength -= 3;  | 
    
    
    142  | 
     | 
     | 
     | 
    
    
    143  | 
     | 
     | 
    		output[0] = input[0] >> 2;  | 
    
    
    144  | 
     | 
     | 
    		output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);  | 
    
    
    145  | 
     | 
     | 
    		output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);  | 
    
    
    146  | 
     | 
     | 
    		output[3] = input[2] & 0x3f;  | 
    
    
    147  | 
     | 
     | 
     | 
    
    
    148  | 
     | 
     | 
    		if (datalength + 4 > targsize)  | 
    
    
    149  | 
     | 
     | 
    			return (-1);  | 
    
    
    150  | 
     | 
     | 
    		target[datalength++] = Base64[output[0]];  | 
    
    
    151  | 
     | 
     | 
    		target[datalength++] = Base64[output[1]];  | 
    
    
    152  | 
     | 
     | 
    		target[datalength++] = Base64[output[2]];  | 
    
    
    153  | 
     | 
     | 
    		target[datalength++] = Base64[output[3]];  | 
    
    
    154  | 
     | 
     | 
    	}  | 
    
    
    155  | 
     | 
     | 
     | 
    
    
    156  | 
     | 
     | 
    	/* Now we worry about padding. */  | 
    
    
    157  | 
     | 
     | 
    	if (0 != srclength) { | 
    
    
    158  | 
     | 
     | 
    		/* Get what's left. */  | 
    
    
    159  | 
     | 
     | 
    		input[0] = input[1] = input[2] = '\0';  | 
    
    
    160  | 
     | 
     | 
    		for (i = 0; i < srclength; i++)  | 
    
    
    161  | 
     | 
     | 
    			input[i] = *src++;  | 
    
    
    162  | 
     | 
     | 
     | 
    
    
    163  | 
     | 
     | 
    		output[0] = input[0] >> 2;  | 
    
    
    164  | 
     | 
     | 
    		output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);  | 
    
    
    165  | 
     | 
     | 
    		output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);  | 
    
    
    166  | 
     | 
     | 
     | 
    
    
    167  | 
     | 
     | 
    		if (datalength + 4 > targsize)  | 
    
    
    168  | 
     | 
     | 
    			return (-1);  | 
    
    
    169  | 
     | 
     | 
    		target[datalength++] = Base64[output[0]];  | 
    
    
    170  | 
     | 
     | 
    		target[datalength++] = Base64[output[1]];  | 
    
    
    171  | 
     | 
     | 
    		if (srclength == 1)  | 
    
    
    172  | 
     | 
     | 
    			target[datalength++] = Pad64;  | 
    
    
    173  | 
     | 
     | 
    		else  | 
    
    
    174  | 
     | 
     | 
    			target[datalength++] = Base64[output[2]];  | 
    
    
    175  | 
     | 
     | 
    		target[datalength++] = Pad64;  | 
    
    
    176  | 
     | 
     | 
    	}  | 
    
    
    177  | 
     | 
     | 
    	if (datalength >= targsize)  | 
    
    
    178  | 
     | 
     | 
    		return (-1);  | 
    
    
    179  | 
     | 
     | 
    	target[datalength] = '\0';	/* Returned value doesn't count \0. */  | 
    
    
    180  | 
     | 
     | 
    	return (datalength);  | 
    
    
    181  | 
     | 
     | 
    }  | 
    
    
    182  | 
     | 
     | 
     | 
    
    
    183  | 
     | 
     | 
    /* skips all whitespace anywhere.  | 
    
    
    184  | 
     | 
     | 
       converts characters, four at a time, starting at (or after)  | 
    
    
    185  | 
     | 
     | 
       src from base - 64 numbers into three 8 bit bytes in the target area.  | 
    
    
    186  | 
     | 
     | 
       it returns the number of data bytes stored at the target, or -1 on error.  | 
    
    
    187  | 
     | 
     | 
     */  | 
    
    
    188  | 
     | 
     | 
     | 
    
    
    189  | 
     | 
     | 
    int  | 
    
    
    190  | 
     | 
     | 
    b64_pton(src, target, targsize)  | 
    
    
    191  | 
     | 
     | 
    	char const *src;  | 
    
    
    192  | 
     | 
     | 
    	u_char *target;  | 
    
    
    193  | 
     | 
     | 
    	size_t targsize;  | 
    
    
    194  | 
     | 
     | 
    { | 
    
    
    195  | 
     | 
     | 
    	int tarindex, state, ch;  | 
    
    
    196  | 
     | 
     | 
    	u_char nextbyte;  | 
    
    
    197  | 
     | 
     | 
    	char *pos;  | 
    
    
    198  | 
     | 
     | 
     | 
    
    
    199  | 
     | 
     | 
    	state = 0;  | 
    
    
    200  | 
     | 
     | 
    	tarindex = 0;  | 
    
    
    201  | 
     | 
     | 
     | 
    
    
    202  | 
     | 
     | 
    	while ((ch = (unsigned char)*src++) != '\0') { | 
    
    
    203  | 
     | 
     | 
    		if (isspace(ch))	/* Skip whitespace anywhere. */  | 
    
    
    204  | 
     | 
     | 
    			continue;  | 
    
    
    205  | 
     | 
     | 
     | 
    
    
    206  | 
     | 
     | 
    		if (ch == Pad64)  | 
    
    
    207  | 
     | 
     | 
    			break;  | 
    
    
    208  | 
     | 
     | 
     | 
    
    
    209  | 
     | 
     | 
    		pos = strchr(Base64, ch);  | 
    
    
    210  | 
     | 
     | 
    		if (pos == 0) 		/* A non-base64 character. */  | 
    
    
    211  | 
     | 
     | 
    			return (-1);  | 
    
    
    212  | 
     | 
     | 
     | 
    
    
    213  | 
     | 
     | 
    		switch (state) { | 
    
    
    214  | 
     | 
     | 
    		case 0:  | 
    
    
    215  | 
     | 
     | 
    			if (target) { | 
    
    
    216  | 
     | 
     | 
    				if (tarindex >= targsize)  | 
    
    
    217  | 
     | 
     | 
    					return (-1);  | 
    
    
    218  | 
     | 
     | 
    				target[tarindex] = (pos - Base64) << 2;  | 
    
    
    219  | 
     | 
     | 
    			}  | 
    
    
    220  | 
     | 
     | 
    			state = 1;  | 
    
    
    221  | 
     | 
     | 
    			break;  | 
    
    
    222  | 
     | 
     | 
    		case 1:  | 
    
    
    223  | 
     | 
     | 
    			if (target) { | 
    
    
    224  | 
     | 
     | 
    				if (tarindex >= targsize)  | 
    
    
    225  | 
     | 
     | 
    					return (-1);  | 
    
    
    226  | 
     | 
     | 
    				target[tarindex]   |=  (pos - Base64) >> 4;  | 
    
    
    227  | 
     | 
     | 
    				nextbyte = ((pos - Base64) & 0x0f) << 4;  | 
    
    
    228  | 
     | 
     | 
    				if (tarindex + 1 < targsize)  | 
    
    
    229  | 
     | 
     | 
    					target[tarindex+1] = nextbyte;  | 
    
    
    230  | 
     | 
     | 
    				else if (nextbyte)  | 
    
    
    231  | 
     | 
     | 
    					return (-1);  | 
    
    
    232  | 
     | 
     | 
    			}  | 
    
    
    233  | 
     | 
     | 
    			tarindex++;  | 
    
    
    234  | 
     | 
     | 
    			state = 2;  | 
    
    
    235  | 
     | 
     | 
    			break;  | 
    
    
    236  | 
     | 
     | 
    		case 2:  | 
    
    
    237  | 
     | 
     | 
    			if (target) { | 
    
    
    238  | 
     | 
     | 
    				if (tarindex >= targsize)  | 
    
    
    239  | 
     | 
     | 
    					return (-1);  | 
    
    
    240  | 
     | 
     | 
    				target[tarindex]   |=  (pos - Base64) >> 2;  | 
    
    
    241  | 
     | 
     | 
    				nextbyte = ((pos - Base64) & 0x03) << 6;  | 
    
    
    242  | 
     | 
     | 
    				if (tarindex + 1 < targsize)  | 
    
    
    243  | 
     | 
     | 
    					target[tarindex+1] = nextbyte;  | 
    
    
    244  | 
     | 
     | 
    				else if (nextbyte)  | 
    
    
    245  | 
     | 
     | 
    					return (-1);  | 
    
    
    246  | 
     | 
     | 
    			}  | 
    
    
    247  | 
     | 
     | 
    			tarindex++;  | 
    
    
    248  | 
     | 
     | 
    			state = 3;  | 
    
    
    249  | 
     | 
     | 
    			break;  | 
    
    
    250  | 
     | 
     | 
    		case 3:  | 
    
    
    251  | 
     | 
     | 
    			if (target) { | 
    
    
    252  | 
     | 
     | 
    				if (tarindex >= targsize)  | 
    
    
    253  | 
     | 
     | 
    					return (-1);  | 
    
    
    254  | 
     | 
     | 
    				target[tarindex] |= (pos - Base64);  | 
    
    
    255  | 
     | 
     | 
    			}  | 
    
    
    256  | 
     | 
     | 
    			tarindex++;  | 
    
    
    257  | 
     | 
     | 
    			state = 0;  | 
    
    
    258  | 
     | 
     | 
    			break;  | 
    
    
    259  | 
     | 
     | 
    		}  | 
    
    
    260  | 
     | 
     | 
    	}  | 
    
    
    261  | 
     | 
     | 
     | 
    
    
    262  | 
     | 
     | 
    	/*  | 
    
    
    263  | 
     | 
     | 
    	 * We are done decoding Base-64 chars.  Let's see if we ended  | 
    
    
    264  | 
     | 
     | 
    	 * on a byte boundary, and/or with erroneous trailing characters.  | 
    
    
    265  | 
     | 
     | 
    	 */  | 
    
    
    266  | 
     | 
     | 
     | 
    
    
    267  | 
     | 
     | 
    	if (ch == Pad64) {			/* We got a pad char. */ | 
    
    
    268  | 
     | 
     | 
    		ch = (unsigned char)*src++;	/* Skip it, get next. */  | 
    
    
    269  | 
     | 
     | 
    		switch (state) { | 
    
    
    270  | 
     | 
     | 
    		case 0:		/* Invalid = in first position */  | 
    
    
    271  | 
     | 
     | 
    		case 1:		/* Invalid = in second position */  | 
    
    
    272  | 
     | 
     | 
    			return (-1);  | 
    
    
    273  | 
     | 
     | 
     | 
    
    
    274  | 
     | 
     | 
    		case 2:		/* Valid, means one byte of info */  | 
    
    
    275  | 
     | 
     | 
    			/* Skip any number of spaces. */  | 
    
    
    276  | 
     | 
     | 
    			for (; ch != '\0'; ch = (unsigned char)*src++)  | 
    
    
    277  | 
     | 
     | 
    				if (!isspace(ch))  | 
    
    
    278  | 
     | 
     | 
    					break;  | 
    
    
    279  | 
     | 
     | 
    			/* Make sure there is another trailing = sign. */  | 
    
    
    280  | 
     | 
     | 
    			if (ch != Pad64)  | 
    
    
    281  | 
     | 
     | 
    				return (-1);  | 
    
    
    282  | 
     | 
     | 
    			ch = (unsigned char)*src++;		/* Skip the = */  | 
    
    
    283  | 
     | 
     | 
    			/* Fall through to "single trailing =" case. */  | 
    
    
    284  | 
     | 
     | 
    			/* FALLTHROUGH */  | 
    
    
    285  | 
     | 
     | 
     | 
    
    
    286  | 
     | 
     | 
    		case 3:		/* Valid, means two bytes of info */  | 
    
    
    287  | 
     | 
     | 
    			/*  | 
    
    
    288  | 
     | 
     | 
    			 * We know this char is an =.  Is there anything but  | 
    
    
    289  | 
     | 
     | 
    			 * whitespace after it?  | 
    
    
    290  | 
     | 
     | 
    			 */  | 
    
    
    291  | 
     | 
     | 
    			for (; ch != '\0'; ch = (unsigned char)*src++)  | 
    
    
    292  | 
     | 
     | 
    				if (!isspace(ch))  | 
    
    
    293  | 
     | 
     | 
    					return (-1);  | 
    
    
    294  | 
     | 
     | 
     | 
    
    
    295  | 
     | 
     | 
    			/*  | 
    
    
    296  | 
     | 
     | 
    			 * Now make sure for cases 2 and 3 that the "extra"  | 
    
    
    297  | 
     | 
     | 
    			 * bits that slopped past the last full byte were  | 
    
    
    298  | 
     | 
     | 
    			 * zeros.  If we don't check them, they become a  | 
    
    
    299  | 
     | 
     | 
    			 * subliminal channel.  | 
    
    
    300  | 
     | 
     | 
    			 */  | 
    
    
    301  | 
     | 
     | 
    			if (target && tarindex < targsize &&  | 
    
    
    302  | 
     | 
     | 
    			    target[tarindex] != 0)  | 
    
    
    303  | 
     | 
     | 
    				return (-1);  | 
    
    
    304  | 
     | 
     | 
    		}  | 
    
    
    305  | 
     | 
     | 
    	} else { | 
    
    
    306  | 
     | 
     | 
    		/*  | 
    
    
    307  | 
     | 
     | 
    		 * We ended by seeing the end of the string.  Make sure we  | 
    
    
    308  | 
     | 
     | 
    		 * have no partial bytes lying around.  | 
    
    
    309  | 
     | 
     | 
    		 */  | 
    
    
    310  | 
     | 
     | 
    		if (state != 0)  | 
    
    
    311  | 
     | 
     | 
    			return (-1);  | 
    
    
    312  | 
     | 
     | 
    	}  | 
    
    
    313  | 
     | 
     | 
     | 
    
    
    314  | 
     | 
     | 
    	return (tarindex);  | 
    
    
    315  | 
     | 
     | 
    }  |