1 files changed, 378 insertions, 0 deletions
diff --git a/src/libstrongswan/asn1/ttodata.c b/src/libstrongswan/asn1/ttodata.c
new file mode 100644
index 000000000..8114b12c5
--- /dev/null
+++ b/src/libstrongswan/asn1/ttodata.c
@@ -0,0 +1,378 @@
+/*
+ * convert from text form of arbitrary data (e.g., keys) to binary
+ * Copyright (C) 2000  Henry Spencer.
+ * 
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Library General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/lgpl.txt>.
+ * 
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
+ * License for more details.
+ */
+
+#include "ttodata.h"
+
+#include <string.h>
+#include <ctype.h>
+
+/* converters and misc */
+static int unhex(const char *, char *, size_t);
+static int unb64(const char *, char *, size_t);
+static int untext(const char *, char *, size_t);
+static const char *badch(const char *, int, char *, size_t);
+
+/* internal error codes for converters */
+#define	SHORT	(-2)		/* internal buffer too short */
+#define	BADPAD	(-3)		/* bad base64 padding */
+#define	BADCH0	(-4)		/* invalid character 0 */
+#define	BADCH1	(-5)		/* invalid character 1 */
+#define	BADCH2	(-6)		/* invalid character 2 */
+#define	BADCH3	(-7)		/* invalid character 3 */
+#define	BADOFF(code) (BADCH0-(code))
+
+/**
+ * @brief convert text to data, with verbose error reports
+ * 
+ * If some of this looks slightly odd, it's because it has changed
+ * repeatedly (from the original atodata()) without a major rewrite.
+ *
+ * @param src
+ * @param srclen	0 means apply strlen()
+ * @param base 		0 means figure it out
+ * @param dst 		need not be valid if dstlen is 0
+ * @param dstlen	
+ * @param lenp		where to record length (NULL is nowhere)
+ * @param errp		error buffer
+ * @param flags
+ * @return			NULL on success, else literal or errp
+ */
+const char *ttodatav(const char *src, size_t srclen, int base, char *dst, size_t dstlen, size_t *lenp, char *errp, size_t errlen, unsigned int flags)
+{
+	size_t ingroup;	/* number of input bytes converted at once */
+	char buf[4];		/* output from conversion */
+	int nbytes;		/* size of output */
+	int (*decode)(const char *, char *, size_t);
+	char *stop;
+	int ndone;
+	int i;
+	int underscoreok;
+	int skipSpace = 0;
+
+	if (srclen == 0)
+		srclen = strlen(src);
+	if (dstlen == 0)
+		dst = buf;	/* point it somewhere valid */
+	stop = dst + dstlen;
+
+	if (base == 0) {
+		if (srclen < 2)
+			return "input too short to be valid";
+		if (*src++ != '0')
+			return "input does not begin with format prefix";
+		switch (*src++) {
+		case 'x':
+		case 'X':
+			base = 16;
+			break;
+		case 's':
+		case 'S':
+			base = 64;
+			break;
+		case 't':
+		case 'T':
+			base = 256;
+			break;
+		default:
+			return "unknown format prefix";
+		}
+		srclen -= 2;
+	}
+	switch (base) {
+	case 16:
+		decode = unhex;
+		underscoreok = 1;
+		ingroup = 2;
+		break;
+	case 64:
+		decode = unb64;
+		underscoreok = 0;
+		ingroup = 4;
+		if(flags & TTODATAV_IGNORESPACE) {
+			skipSpace = 1;
+		}
+		break;
+
+	case 256:
+		decode = untext;
+		ingroup = 1;
+		underscoreok = 0;
+		break;
+	default:
+		return "unknown base";
+	}
+
+	/* proceed */
+	ndone = 0;
+	while (srclen > 0) {
+		char stage[4];	/* staging area for group */
+		size_t sl = 0;
+
+		/* Grab ingroup characters into stage,
+		 * squeezing out blanks if we are supposed to ignore them.
+		 */
+		for (sl = 0; sl < ingroup; src++, srclen--) {
+			if (srclen == 0)
+				return "input ends in mid-byte, perhaps truncated";
+			else if (!(skipSpace && (*src == ' ' || *src == '\t')))
+				stage[sl++] = *src;
+		}
+		
+		nbytes = (*decode)(stage, buf, sizeof(buf));
+		switch (nbytes) {
+		case BADCH0:
+		case BADCH1:
+		case BADCH2:
+		case BADCH3:
+			return badch(stage, nbytes, errp, errlen);
+		case SHORT:
+			return "internal buffer too short (\"can't happen\")";
+		case BADPAD:
+			return "bad (non-zero) padding at end of base64 input";
+		}
+		if (nbytes <= 0)
+			return "unknown internal error";
+		for (i = 0; i < nbytes; i++) {
+			if (dst < stop)
+				*dst++ = buf[i];
+			ndone++;
+		}
+		while (srclen >= 1 && skipSpace && (*src == ' ' || *src == '\t')){
+			src++;
+			srclen--;
+		}
+		if (underscoreok && srclen > 1 && *src == '_') {
+			/* srclen > 1 means not last character */
+			src++;
+			srclen--;
+		}
+	}
+
+	if (ndone == 0)
+		return "no data bytes specified by input";
+	if (lenp != NULL)
+		*lenp = ndone;
+	return NULL;
+}
+
+/**
+ * @brief ttodata - convert text to data
+ * 
+ * @param src
+ * @param srclen	0 means apply strlen()
+ * @param base		0 means figure it out
+ * @param dst		need not be valid if dstlen is 0
+ * @param dstlen
+ * @param lenp		where to record length (NULL is nowhere)
+ * @return			NULL on success, else literal
+ */
+const char *ttodata(const char *src, size_t srclen, int base, char *dst, size_t dstlen, size_t *lenp)
+{
+	return ttodatav(src, srclen, base, dst, dstlen, lenp, (char *)NULL,
+			(size_t)0, TTODATAV_SPACECOUNTS);
+}
+
+/**
+ * @brief atodata - convert ASCII to data
+ * 
+ * backward-compatibility interface
+ * 
+ * @param src
+ * @param srclen
+ * @param dst
+ * @param dstlen
+ * @return 			0 for failure, true length for success
+ */
+size_t atodata(const char *src, size_t srclen, char *dst, size_t dstlen)
+{
+	size_t len;
+	const char *err;
+
+	err = ttodata(src, srclen, 0, dst, dstlen, &len);
+	if (err != NULL)
+		return 0;
+	return len;
+}
+
+/**
+ * @brief  atobytes - convert ASCII to data bytes
+ *
+ * another backward-compatibility interface
+ */
+const char *atobytes(const char *src, size_t srclen, char *dst, size_t dstlen, size_t *lenp)
+{
+	return ttodata(src, srclen, 0, dst, dstlen, lenp);
+}
+
+/**
+ * @brief unhex - convert two ASCII hex digits to byte
+ * 
+ * @param src 		known to be full length
+ * @param dstnumber of result bytes, or error code
+ * @param dstlen	not large enough is a failure
+ * @return			
+ */
+static int unhex(const char *src, char *dst, size_t dstlen)
+{
+	char *p;
+	unsigned byte;
+	static char hex[] = "0123456789abcdef";
+
+	if (dstlen < 1)
+		return SHORT;
+	
+	p = strchr(hex, *src);
+	if (p == NULL)
+		p = strchr(hex, tolower(*src));
+	if (p == NULL)
+		return BADCH0;
+	byte = (p - hex) << 4;
+	src++;
+
+	p = strchr(hex, *src);
+	if (p == NULL)
+		p = strchr(hex, tolower(*src));
+	if (p == NULL)
+		return BADCH1;
+	byte |= (p - hex);
+
+	*dst = byte;
+	return 1;
+}
+
+/**
+ * @brief unb64 - convert four ASCII base64 digits to three bytes
+ *
+ * Note that a base64 digit group is padded out with '=' if it represents
+ * less than three bytes:  one byte is dd==, two is ddd=, three is dddd.
+ *
+ * @param src		known to be full length 
+ * @param dst		
+ * @param dstlen	
+ * @return			number of result bytes, or error code
+ */
+static int unb64(const char *src, char *dst, size_t dstlen)
+{
+	char *p;
+	unsigned byte1;
+	unsigned byte2;
+	static char base64[] =
+	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+	if (dstlen < 3)
+		return SHORT;
+
+	p = strchr(base64, *src++);
+
+	if (p == NULL)
+		return BADCH0;
+	byte1 = (p - base64) << 2;	/* first six bits */
+
+	p = strchr(base64, *src++);
+	if (p == NULL) {
+		return BADCH1;
+	}
+
+	byte2 = p - base64;		/* next six:  two plus four */
+	*dst++ = byte1 | (byte2 >> 4);
+	byte1 = (byte2 & 0xf) << 4;
+
+	p = strchr(base64, *src++);
+	if (p == NULL) {
+		if (*(src-1) == '=' && *src == '=') {
+			if (byte1 != 0)		/* bad padding */
+				return BADPAD;
+			return 1;
+		}
+		return BADCH2;
+	}
+
+	byte2 = p - base64;		/* next six:  four plus two */
+	*dst++ = byte1 | (byte2 >> 2);
+	byte1 = (byte2 & 0x3) << 6;
+
+	p = strchr(base64, *src++);
+	if (p == NULL) {
+		if (*(src-1) == '=') {
+			if (byte1 != 0)		/* bad padding */
+				return BADPAD;
+			return 2;
+		}
+		return BADCH3;
+	}
+	byte2 = p - base64;		/* last six */
+	*dst++ = byte1 | byte2;
+
+	return 3;
+}
+
+/**
+ * @brief untext - convert one ASCII character to byte
+ * 
+ * @param src		known to be full length
+ * @param dst		
+ * @param dstlen	not large enough is a failure
+ * @return 			number of result bytes, or error code
+ */
+static int untext(const char *src, char *dst, size_t dstlen)
+{
+	if (dstlen < 1)
+		return SHORT;
+
+	*dst = *src;
+	return 1;
+}
+
+/**
+ * @brief badch - produce a nice complaint about an unknown character
+ *
+ * If the compiler complains that the array bigenough[] has a negative
+ * size, that means the TTODATAV_BUF constant has been set too small.
+ * 
+ * @param src		
+ * @param errcode	
+ * @param errp		might be NULL
+ * @param errlen	
+ * @return			literal or errp
+ */
+static const char *badch(const char *src, int errcode, char *errp, size_t errlen)
+{
+	static const char pre[] = "unknown character (`";
+	static const char suf[] = "') in input";
+	char buf[5];
+#	define	REQD	(sizeof(pre) - 1 + sizeof(buf) - 1 + sizeof(suf))
+	struct sizecheck {
+		char bigenough[TTODATAV_BUF - REQD];	/* see above */
+	};
+	char ch;
+
+	if (errp == NULL || errlen < REQD)
+		return "unknown character in input";
+	strcpy(errp, pre);
+	ch = *(src + BADOFF(errcode));
+	if (isprint(ch)) {
+		buf[0] = ch;
+		buf[1] = '\0';
+	} else {
+		buf[0] = '\\';
+		buf[1] = ((ch & 0700) >> 6) + '0';
+		buf[2] = ((ch & 0070) >> 3) + '0';
+		buf[3] = ((ch & 0007) >> 0) + '0';
+		buf[4] = '\0';
+	}
+	strcat(errp, buf);
+	strcat(errp, suf);
+	return (const char *)errp;
+}