[openssh.git] / openbsd-compat / base64.c

/*	$OpenBSD: base64.c,v 1.5 2006/10/21 09:55:03 otto Exp $	*/

/*
 * Copyright (c) 1996 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/*
 * Portions Copyright (c) 1995 by International Business Machines, Inc.
 *
 * International Business Machines, Inc. (hereinafter called IBM) grants
 * permission under its copyrights to use, copy, modify, and distribute this
 * Software with or without fee, provided that the above copyright notice and
 * all paragraphs of this notice appear in all copies, and that the name of IBM
 * not be used in connection with the marketing of any product incorporating
 * the Software or modifications thereof, without specific, written prior
 * permission.
 *
 * To the extent it has a right to do so, IBM grants an immunity from suit
 * under its patents, if any, for the use, sale or manufacture of products to
 * the extent that such products are used for performing Domain Name System
 * dynamic updates in TCP/IP networks by means of the Software.  No immunity is
 * granted for any product per se or for any other function of any product.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE.  IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL,
 * DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN
 * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES.
 */

/* OPENBSD ORIGINAL: lib/libc/net/base64.c */

#include "includes.h"

#if (!defined(HAVE_B64_NTOP) && !defined(HAVE___B64_NTOP)) || (!defined(HAVE_B64_PTON) && !defined(HAVE___B64_PTON))

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <ctype.h>
#include <stdio.h>

#include <stdlib.h>
#include <string.h>

#include "base64.h"

static const char Base64[] =
	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const char Pad64 = '=';

/* (From RFC1521 and draft-ietf-dnssec-secext-03.txt)
   The following encoding technique is taken from RFC 1521 by Borenstein
   and Freed.  It is reproduced here in a slightly edited form for
   convenience.

   A 65-character subset of US-ASCII is used, enabling 6 bits to be
   represented per printable character. (The extra 65th character, "=",
   is used to signify a special processing function.)

   The encoding process represents 24-bit groups of input bits as output
   strings of 4 encoded characters. Proceeding from left to right, a
   24-bit input group is formed by concatenating 3 8-bit input groups.
   These 24 bits are then treated as 4 concatenated 6-bit groups, each
   of which is translated into a single digit in the base64 alphabet.

   Each 6-bit group is used as an index into an array of 64 printable
   characters. The character referenced by the index is placed in the
   output string.

                         Table 1: The Base64 Alphabet

      Value Encoding  Value Encoding  Value Encoding  Value Encoding
          0 A            17 R            34 i            51 z
          1 B            18 S            35 j            52 0
          2 C            19 T            36 k            53 1
          3 D            20 U            37 l            54 2
          4 E            21 V            38 m            55 3
          5 F            22 W            39 n            56 4
          6 G            23 X            40 o            57 5
          7 H            24 Y            41 p            58 6
          8 I            25 Z            42 q            59 7
          9 J            26 a            43 r            60 8
         10 K            27 b            44 s            61 9
         11 L            28 c            45 t            62 +
         12 M            29 d            46 u            63 /
         13 N            30 e            47 v
         14 O            31 f            48 w         (pad) =
         15 P            32 g            49 x
         16 Q            33 h            50 y

   Special processing is performed if fewer than 24 bits are available
   at the end of the data being encoded.  A full encoding quantum is
   always completed at the end of a quantity.  When fewer than 24 input
   bits are available in an input group, zero bits are added (on the
   right) to form an integral number of 6-bit groups.  Padding at the
   end of the data is performed using the '=' character.

   Since all base64 input is an integral number of octets, only the
         -------------------------------------------------                       
   following cases can arise:
   
       (1) the final quantum of encoding input is an integral
           multiple of 24 bits; here, the final unit of encoded
	   output will be an integral multiple of 4 characters
	   with no "=" padding,
       (2) the final quantum of encoding input is exactly 8 bits;
           here, the final unit of encoded output will be two
	   characters followed by two "=" padding characters, or
       (3) the final quantum of encoding input is exactly 16 bits;
           here, the final unit of encoded output will be three
	   characters followed by one "=" padding character.
   */

#if !defined(HAVE_B64_NTOP) && !defined(HAVE___B64_NTOP) 
int
b64_ntop(u_char const *src, size_t srclength, char *target, size_t targsize)
{
	size_t datalength = 0;
	u_char input[3];
	u_char output[4];
	u_int i;

	while (2 < srclength) {
		input[0] = *src++;
		input[1] = *src++;
		input[2] = *src++;
		srclength -= 3;

		output[0] = input[0] >> 2;
		output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);
		output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);
		output[3] = input[2] & 0x3f;

		if (datalength + 4 > targsize)
			return (-1);
		target[datalength++] = Base64[output[0]];
		target[datalength++] = Base64[output[1]];
		target[datalength++] = Base64[output[2]];
		target[datalength++] = Base64[output[3]];
	}
    
	/* Now we worry about padding. */
	if (0 != srclength) {
		/* Get what's left. */
		input[0] = input[1] = input[2] = '\0';
		for (i = 0; i < srclength; i++)
			input[i] = *src++;
	
		output[0] = input[0] >> 2;
		output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);
		output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);

		if (datalength + 4 > targsize)
			return (-1);
		target[datalength++] = Base64[output[0]];
		target[datalength++] = Base64[output[1]];
		if (srclength == 1)
			target[datalength++] = Pad64;
		else
			target[datalength++] = Base64[output[2]];
		target[datalength++] = Pad64;
	}
	if (datalength >= targsize)
		return (-1);
	target[datalength] = '\0';	/* Returned value doesn't count \0. */
	return (datalength);
}
#endif /* !defined(HAVE_B64_NTOP) && !defined(HAVE___B64_NTOP) */

#if !defined(HAVE_B64_PTON) && !defined(HAVE___B64_PTON)

/* skips all whitespace anywhere.
   converts characters, four at a time, starting at (or after)
   src from base - 64 numbers into three 8 bit bytes in the target area.
   it returns the number of data bytes stored at the target, or -1 on error.
 */

int
b64_pton(char const *src, u_char *target, size_t targsize)
{
	u_int tarindex, state;
	int ch;
	char *pos;

	state = 0;
	tarindex = 0;

	while ((ch = *src++) != '\0') {
		if (isspace(ch))	/* Skip whitespace anywhere. */
			continue;

		if (ch == Pad64)
			break;

		pos = strchr(Base64, ch);
		if (pos == 0) 		/* A non-base64 character. */
			return (-1);

		switch (state) {
		case 0:
			if (target) {
				if (tarindex >= targsize)
					return (-1);
				target[tarindex] = (pos - Base64) << 2;
			}
			state = 1;
			break;
		case 1:
			if (target) {
				if (tarindex + 1 >= targsize)
					return (-1);
				target[tarindex]   |=  (pos - Base64) >> 4;
				target[tarindex+1]  = ((pos - Base64) & 0x0f)
							<< 4 ;
			}
			tarindex++;
			state = 2;
			break;
		case 2:
			if (target) {
				if (tarindex + 1 >= targsize)
					return (-1);
				target[tarindex]   |=  (pos - Base64) >> 2;
				target[tarindex+1]  = ((pos - Base64) & 0x03)
							<< 6;
			}
			tarindex++;
			state = 3;
			break;
		case 3:
			if (target) {
				if (tarindex >= targsize)
					return (-1);
				target[tarindex] |= (pos - Base64);
			}
			tarindex++;
			state = 0;
			break;
		}
	}

	/*
	 * We are done decoding Base-64 chars.  Let's see if we ended
	 * on a byte boundary, and/or with erroneous trailing characters.
	 */

	if (ch == Pad64) {		/* We got a pad char. */
		ch = *src++;		/* Skip it, get next. */
		switch (state) {
		case 0:		/* Invalid = in first position */
		case 1:		/* Invalid = in second position */
			return (-1);

		case 2:		/* Valid, means one byte of info */
			/* Skip any number of spaces. */
			for (; ch != '\0'; ch = *src++)
				if (!isspace(ch))
					break;
			/* Make sure there is another trailing = sign. */
			if (ch != Pad64)
				return (-1);
			ch = *src++;		/* Skip the = */
			/* Fall through to "single trailing =" case. */
			/* FALLTHROUGH */

		case 3:		/* Valid, means two bytes of info */
			/*
			 * We know this char is an =.  Is there anything but
			 * whitespace after it?
			 */
			for (; ch != '\0'; ch = *src++)
				if (!isspace(ch))
					return (-1);

			/*
			 * Now make sure for cases 2 and 3 that the "extra"
			 * bits that slopped past the last full byte were
			 * zeros.  If we don't check them, they become a
			 * subliminal channel.
			 */
			if (target && target[tarindex] != 0)
				return (-1);
		}
	} else {
		/*
		 * We ended by seeing the end of the string.  Make sure we
		 * have no partial bytes lying around.
		 */
		if (state != 0)
			return (-1);
	}

	return (tarindex);
}

#endif /* !defined(HAVE_B64_PTON) && !defined(HAVE___B64_PTON) */
#endif
Commit	Line	Data
a9733dc0	1	/* $OpenBSD: base64.c,v 1.5 2006/10/21 09:55:03 otto Exp $ */
1d1ffb87	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
f6d4fb87	45	/* OPENBSD ORIGINAL: lib/libc/net/base64.c */
f6d4fb87	46
17962c40	47	#include "includes.h"
1d1ffb87	48
19160674	49	#if (!defined(HAVE_B64_NTOP) && !defined(HAVE___B64_NTOP)) \|\| (!defined(HAVE_B64_PTON) && !defined(HAVE___B64_PTON))
1d1ffb87	50
	51	#include <sys/types.h>
	52	#include <sys/param.h>
	53	#include <sys/socket.h>
	54	#include <netinet/in.h>
	55	#include <arpa/inet.h>
	56
	57	#include <ctype.h>
1d1ffb87	58	#include <stdio.h>
	59
	60	#include <stdlib.h>
	61	#include <string.h>
	62
9c8dbb1b	63	#include "base64.h"
eba02c94	64
1d1ffb87	65	static const char Base64[] =
	66	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
	67	static const char Pad64 = '=';
	68
	69	/* (From RFC1521 and draft-ietf-dnssec-secext-03.txt)
	70	The following encoding technique is taken from RFC 1521 by Borenstein
	71	and Freed. It is reproduced here in a slightly edited form for
	72	convenience.
	73
	74	A 65-character subset of US-ASCII is used, enabling 6 bits to be
	75	represented per printable character. (The extra 65th character, "=",
	76	is used to signify a special processing function.)
	77
	78	The encoding process represents 24-bit groups of input bits as output
	79	strings of 4 encoded characters. Proceeding from left to right, a
	80	24-bit input group is formed by concatenating 3 8-bit input groups.
	81	These 24 bits are then treated as 4 concatenated 6-bit groups, each
	82	of which is translated into a single digit in the base64 alphabet.
	83
	84	Each 6-bit group is used as an index into an array of 64 printable
	85	characters. The character referenced by the index is placed in the
	86	output string.
	87
	88	Table 1: The Base64 Alphabet
	89
	90	Value Encoding Value Encoding Value Encoding Value Encoding
	91	0 A 17 R 34 i 51 z
	92	1 B 18 S 35 j 52 0
	93	2 C 19 T 36 k 53 1
	94	3 D 20 U 37 l 54 2
	95	4 E 21 V 38 m 55 3
	96	5 F 22 W 39 n 56 4
	97	6 G 23 X 40 o 57 5
	98	7 H 24 Y 41 p 58 6
	99	8 I 25 Z 42 q 59 7
	100	9 J 26 a 43 r 60 8
	101	10 K 27 b 44 s 61 9
	102	11 L 28 c 45 t 62 +
	103	12 M 29 d 46 u 63 /
	104	13 N 30 e 47 v
	105	14 O 31 f 48 w (pad) =
	106	15 P 32 g 49 x
	107	16 Q 33 h 50 y
	108
	109	Special processing is performed if fewer than 24 bits are available
	110	at the end of the data being encoded. A full encoding quantum is
	111	always completed at the end of a quantity. When fewer than 24 input
	112	bits are available in an input group, zero bits are added (on the
	113	right) to form an integral number of 6-bit groups. Padding at the
	114	end of the data is performed using the '=' character.
	115
	116	Since all base64 input is an integral number of octets, only the
	117	-------------------------------------------------
	118	following cases can arise:
	119
	120	(1) the final quantum of encoding input is an integral
	121	multiple of 24 bits; here, the final unit of encoded
	122	output will be an integral multiple of 4 characters
	123	with no "=" padding,
	124	(2) the final quantum of encoding input is exactly 8 bits;
	125	here, the final unit of encoded output will be two
	126	characters followed by two "=" padding characters, or
	127	(3) the final quantum of encoding input is exactly 16 bits;
	128	here, the final unit of encoded output will be three
129	characters followed by one "=" padding character.
130	*/
131
19160674	132	#if !defined(HAVE_B64_NTOP) && !defined(HAVE___B64_NTOP)
1d1ffb87	133	int
	134	b64_ntop(u_char const src, size_t srclength, char target, size_t targsize)
	135	{
	136	size_t datalength = 0;
	137	u_char input[3];
	138	u_char output[4];
3e6325a6	139	u_int i;
1d1ffb87	140
	141	while (2 < srclength) {
	142	input[0] = *src++;
	143	input[1] = *src++;
	144	input[2] = *src++;
	145	srclength -= 3;
	146
	147	output[0] = input[0] >> 2;
	148	output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);
	149	output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);
	150	output[3] = input[2] & 0x3f;
1d1ffb87	151
	152	if (datalength + 4 > targsize)
	153	return (-1);
	154	target[datalength++] = Base64[output[0]];
	155	target[datalength++] = Base64[output[1]];
	156	target[datalength++] = Base64[output[2]];
	157	target[datalength++] = Base64[output[3]];
	158	}
	159
	160	/* Now we worry about padding. */
	161	if (0 != srclength) {
	162	/* Get what's left. */
	163	input[0] = input[1] = input[2] = '\0';
	164	for (i = 0; i < srclength; i++)
	165	input[i] = *src++;
	166
	167	output[0] = input[0] >> 2;
	168	output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);
	169	output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);
1d1ffb87	170
	171	if (datalength + 4 > targsize)
	172	return (-1);
	173	target[datalength++] = Base64[output[0]];
	174	target[datalength++] = Base64[output[1]];
	175	if (srclength == 1)
	176	target[datalength++] = Pad64;
	177	else
	178	target[datalength++] = Base64[output[2]];
	179	target[datalength++] = Pad64;
	180	}
	181	if (datalength >= targsize)
	182	return (-1);
	183	target[datalength] = '\0'; /* Returned value doesn't count \0. */
	184	return (datalength);
	185	}
19160674	186	#endif /* !defined(HAVE_B64_NTOP) && !defined(HAVE___B64_NTOP) */
	187
	188	#if !defined(HAVE_B64_PTON) && !defined(HAVE___B64_PTON)
1d1ffb87	189
	190	/* skips all whitespace anywhere.
	191	converts characters, four at a time, starting at (or after)
	192	src from base - 64 numbers into three 8 bit bytes in the target area.
	193	it returns the number of data bytes stored at the target, or -1 on error.
	194	*/
	195
	196	int
	197	b64_pton(char const src, u_char target, size_t targsize)
	198	{
3e6325a6	199	u_int tarindex, state;
3e6325a6	200	int ch;
1d1ffb87	201	char *pos;
	202
	203	state = 0;
	204	tarindex = 0;
	205
	206	while ((ch = *src++) != '\0') {
	207	if (isspace(ch)) /* Skip whitespace anywhere. */
	208	continue;
	209
	210	if (ch == Pad64)
	211	break;
	212
	213	pos = strchr(Base64, ch);
	214	if (pos == 0) /* A non-base64 character. */
	215	return (-1);
	216
	217	switch (state) {
	218	case 0:
	219	if (target) {
	220	if (tarindex >= targsize)
	221	return (-1);
	222	target[tarindex] = (pos - Base64) << 2;
	223	}
	224	state = 1;
	225	break;
	226	case 1:
	227	if (target) {
	228	if (tarindex + 1 >= targsize)
	229	return (-1);
	230	target[tarindex] \|= (pos - Base64) >> 4;
	231	target[tarindex+1] = ((pos - Base64) & 0x0f)
	232	<< 4 ;
	233	}
	234	tarindex++;
	235	state = 2;
	236	break;
	237	case 2:
	238	if (target) {
	239	if (tarindex + 1 >= targsize)
	240	return (-1);
	241	target[tarindex] \|= (pos - Base64) >> 2;
	242	target[tarindex+1] = ((pos - Base64) & 0x03)
	243	<< 6;
	244	}
	245	tarindex++;
	246	state = 3;
	247	break;
	248	case 3:
	249	if (target) {
	250	if (tarindex >= targsize)
	251	return (-1);
	252	target[tarindex] \|= (pos - Base64);
	253	}
	254	tarindex++;
	255	state = 0;
	256	break;
	257	}
	258	}
	259
	260	/*
	261	* We are done decoding Base-64 chars. Let's see if we ended
	262	* on a byte boundary, and/or with erroneous trailing characters.
	263	*/
	264
265	if (ch == Pad64) { /* We got a pad char. */
266	ch = src++; / Skip it, get next. */
267	switch (state) {
268	case 0: /* Invalid = in first position */
269	case 1: /* Invalid = in second position */
270	return (-1);
271
272	case 2: /* Valid, means one byte of info */
273	/* Skip any number of spaces. */
274	for (; ch != '\0'; ch = *src++)
275	if (!isspace(ch))
276	break;
277	/* Make sure there is another trailing = sign. */
278	if (ch != Pad64)
279	return (-1);
280	ch = src++; / Skip the = */
281	/* Fall through to "single trailing =" case. */
282	/* FALLTHROUGH */
283
284	case 3: /* Valid, means two bytes of info */
285	/*
286	* We know this char is an =. Is there anything but
287	* whitespace after it?
288	*/
289	for (; ch != '\0'; ch = *src++)
290	if (!isspace(ch))
291	return (-1);
292
293	/*
294	* Now make sure for cases 2 and 3 that the "extra"
295	* bits that slopped past the last full byte were
296	* zeros. If we don't check them, they become a
297	* subliminal channel.
298	*/
299	if (target && target[tarindex] != 0)
300	return (-1);
301	}
302	} else {
303	/*
304	* We ended by seeing the end of the string. Make sure we
305	* have no partial bytes lying around.
306	*/
307	if (state != 0)
308	return (-1);
309	}
310
311	return (tarindex);
312	}
313
19160674	314	#endif /* !defined(HAVE_B64_PTON) && !defined(HAVE___B64_PTON) */
19160674	315	#endif