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author | Martin Willi <martin@strongswan.org> | 2006-04-28 10:51:19 +0000 |
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committer | Martin Willi <martin@strongswan.org> | 2006-04-28 10:51:19 +0000 |
commit | 1029d84d2365ca6e6b2d2a96e5c0a1fad3c127e3 (patch) | |
tree | d7d1152d0651f01f023b4faa09fc51f936f89e60 /src/charon/lib/asn1/ttodata.c | |
parent | 51c3484a9f70f03b2ea73151428a40e785c0c56c (diff) | |
download | strongswan-1029d84d2365ca6e6b2d2a96e5c0a1fad3c127e3.tar.bz2 strongswan-1029d84d2365ca6e6b2d2a96e5c0a1fad3c127e3.tar.xz |
Diffstat (limited to 'src/charon/lib/asn1/ttodata.c')
-rw-r--r-- | src/charon/lib/asn1/ttodata.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/src/charon/lib/asn1/ttodata.c b/src/charon/lib/asn1/ttodata.c new file mode 100644 index 000000000..5e8149955 --- /dev/null +++ b/src/charon/lib/asn1/ttodata.c @@ -0,0 +1,374 @@ +/* + * 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)) + +/* + - ttodatav - 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. + */ +const char * /* NULL on success, else literal or errp */ +ttodatav(src, srclen, base, dst, dstlen, lenp, errp, errlen, flags) +const char *src; +size_t srclen; /* 0 means apply strlen() */ +int base; /* 0 means figure it out */ +char *dst; /* need not be valid if dstlen is 0 */ +size_t dstlen; +size_t *lenp; /* where to record length (NULL is nowhere) */ +char *errp; /* error buffer */ +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; +} + +/* + - ttodata - convert text to data + */ +const char * /* NULL on success, else literal */ +ttodata(src, srclen, base, dst, dstlen, lenp) +const char *src; +size_t srclen; /* 0 means apply strlen() */ +int base; /* 0 means figure it out */ +char *dst; /* need not be valid if dstlen is 0 */ +size_t dstlen; +size_t *lenp; /* where to record length (NULL is nowhere) */ +{ + return ttodatav(src, srclen, base, dst, dstlen, lenp, (char *)NULL, + (size_t)0, TTODATAV_SPACECOUNTS); +} + +/* + - atodata - convert ASCII to data + * backward-compatibility interface + */ +size_t /* 0 for failure, true length for success */ +atodata(src, srclen, dst, dstlen) +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; +} + +/* + - atobytes - convert ASCII to data bytes + * another backward-compatibility interface + */ +const char * +atobytes(src, srclen, dst, dstlen, lenp) +const char *src; +size_t srclen; +char *dst; +size_t dstlen; +size_t *lenp; +{ + return ttodata(src, srclen, 0, dst, dstlen, lenp); +} + +/* + - unhex - convert two ASCII hex digits to byte + */ +static int /* number of result bytes, or error code */ +unhex(src, dst, dstlen) +const char *src; /* known to be full length */ +char *dst; +size_t dstlen; /* not large enough is a failure */ +{ + 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; +} + +/* + - 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. + */ +static int /* number of result bytes, or error code */ +unb64(src, dst, dstlen) +const char *src; /* known to be full length */ +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; +} + +/* + - untext - convert one ASCII character to byte + */ +static int /* number of result bytes, or error code */ +untext(src, dst, dstlen) +const char *src; /* known to be full length */ +char *dst; +size_t dstlen; /* not large enough is a failure */ +{ + if (dstlen < 1) + return SHORT; + + *dst = *src; + return 1; +} + +/* + - 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. + */ +static const char * /* literal or errp */ +badch(src, errcode, errp, errlen) +const char *src; +int errcode; +char *errp; /* might be NULL */ +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; +} |