/* $NetBSD: vis.c,v 1.44 2011/03/12 19:52:48 christos Exp $ */ /*- * Copyright (c) 1989, 1993 * The Regents of the University of California. 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 University 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 REGENTS 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 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /*- * Copyright (c) 1999, 2005 The NetBSD Foundation, Inc. * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include "config.h" #if defined(LIBC_SCCS) && !defined(lint) __RCSID("$NetBSD: vis.c,v 1.44 2011/03/12 19:52:48 christos Exp $"); #endif /* LIBC_SCCS and not lint */ #include #include #include #include #include #ifdef __weak_alias __weak_alias(strvisx,_strvisx) #endif #if !HAVE_VIS || !HAVE_SVIS #include #include #include #include static char *do_svis(char *, size_t *, int, int, int, const char *); #undef BELL #define BELL '\a' #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') #define iswhite(c) (c == ' ' || c == '\t' || c == '\n') #define issafe(c) (c == '\b' || c == BELL || c == '\r') #define xtoa(c) "0123456789abcdef"[c] #define XTOA(c) "0123456789ABCDEF"[c] #define MAXEXTRAS 5 #define MAKEEXTRALIST(flag, extra, orig_str) \ do { \ const char *orig = orig_str; \ const char *o = orig; \ char *e; \ while (*o++) \ continue; \ extra = malloc((size_t)((o - orig) + MAXEXTRAS)); \ if (!extra) break; \ for (o = orig, e = extra; (*e++ = *o++) != '\0';) \ continue; \ e--; \ if (flag & VIS_SP) *e++ = ' '; \ if (flag & VIS_TAB) *e++ = '\t'; \ if (flag & VIS_NL) *e++ = '\n'; \ if ((flag & VIS_NOSLASH) == 0) *e++ = '\\'; \ *e = '\0'; \ } while (/*CONSTCOND*/0) /* * This is do_hvis, for HTTP style (RFC 1808) */ static char * do_hvis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra) { if ((isascii(c) && isalnum(c)) /* safe */ || c == '$' || c == '-' || c == '_' || c == '.' || c == '+' /* extra */ || c == '!' || c == '*' || c == '\'' || c == '(' || c == ')' || c == ',') { dst = do_svis(dst, dlen, c, flag, nextc, extra); } else { if (dlen) { if (*dlen < 3) return NULL; *dlen -= 3; } *dst++ = '%'; *dst++ = xtoa(((unsigned int)c >> 4) & 0xf); *dst++ = xtoa((unsigned int)c & 0xf); } return dst; } /* * This is do_mvis, for Quoted-Printable MIME (RFC 2045) * NB: No handling of long lines or CRLF. */ static char * do_mvis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra) { if ((c != '\n') && /* Space at the end of the line */ ((isspace(c) && (nextc == '\r' || nextc == '\n')) || /* Out of range */ (!isspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) || /* Specific char to be escaped */ strchr("#$@[\\]^`{|}~", c) != NULL)) { if (dlen) { if (*dlen < 3) return NULL; *dlen -= 3; } *dst++ = '='; *dst++ = XTOA(((unsigned int)c >> 4) & 0xf); *dst++ = XTOA((unsigned int)c & 0xf); } else { dst = do_svis(dst, dlen, c, flag, nextc, extra); } return dst; } /* * This is do_vis, the central code of vis. * dst: Pointer to the destination buffer * c: Character to encode * flag: Flag word * nextc: The character following 'c' * extra: Pointer to the list of extra characters to be * backslash-protected. */ static char * do_svis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra) { int isextra; size_t odlen = dlen ? *dlen : 0; isextra = strchr(extra, c) != NULL; #define HAVE(x) \ do { \ if (dlen) { \ if (*dlen < (x)) \ goto out; \ *dlen -= (x); \ } \ } while (/*CONSTCOND*/0) if (!isextra && isascii(c) && (isgraph(c) || iswhite(c) || ((flag & VIS_SAFE) && issafe(c)))) { HAVE(1); *dst++ = c; return dst; } if (flag & VIS_CSTYLE) { HAVE(2); switch (c) { case '\n': *dst++ = '\\'; *dst++ = 'n'; return dst; case '\r': *dst++ = '\\'; *dst++ = 'r'; return dst; case '\b': *dst++ = '\\'; *dst++ = 'b'; return dst; case BELL: *dst++ = '\\'; *dst++ = 'a'; return dst; case '\v': *dst++ = '\\'; *dst++ = 'v'; return dst; case '\t': *dst++ = '\\'; *dst++ = 't'; return dst; case '\f': *dst++ = '\\'; *dst++ = 'f'; return dst; case ' ': *dst++ = '\\'; *dst++ = 's'; return dst; case '\0': *dst++ = '\\'; *dst++ = '0'; if (isoctal(nextc)) { HAVE(2); *dst++ = '0'; *dst++ = '0'; } return dst; default: if (isgraph(c)) { *dst++ = '\\'; *dst++ = c; return dst; } if (dlen) *dlen = odlen; } } if (isextra || ((c & 0177) == ' ') || (flag & VIS_OCTAL)) { HAVE(4); *dst++ = '\\'; *dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + '0'; *dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + '0'; *dst++ = (c & 07) + '0'; } else { if ((flag & VIS_NOSLASH) == 0) { HAVE(1); *dst++ = '\\'; } if (c & 0200) { HAVE(1); c &= 0177; *dst++ = 'M'; } if (iscntrl(c)) { HAVE(2); *dst++ = '^'; if (c == 0177) *dst++ = '?'; else *dst++ = c + '@'; } else { HAVE(2); *dst++ = '-'; *dst++ = c; } } return dst; out: *dlen = odlen; return NULL; } typedef char *(*visfun_t)(char *, size_t *, int, int, int, const char *); /* * Return the appropriate encoding function depending on the flags given. */ static visfun_t getvisfun(int flag) { if (flag & VIS_HTTPSTYLE) return do_hvis; if (flag & VIS_MIMESTYLE) return do_mvis; return do_svis; } /* * isnvis - visually encode characters, also encoding the characters * pointed to by `extra' */ static char * isnvis(char *dst, size_t *dlen, int c, int flag, int nextc, const char *extra) { char *nextra = NULL; visfun_t f; _DIAGASSERT(dst != NULL); _DIAGASSERT(extra != NULL); MAKEEXTRALIST(flag, nextra, extra); if (!nextra) { if (dlen && *dlen == 0) { errno = ENOSPC; return NULL; } *dst = '\0'; /* can't create nextra, return "" */ return dst; } f = getvisfun(flag); dst = (*f)(dst, dlen, c, flag, nextc, nextra); free(nextra); if (dst == NULL || (dlen && *dlen == 0)) { errno = ENOSPC; return NULL; } *dst = '\0'; return dst; } char * svis(char *dst, int c, int flag, int nextc, const char *extra) { return isnvis(dst, NULL, c, flag, nextc, extra); } char * snvis(char *dst, size_t dlen, int c, int flag, int nextc, const char *extra) { return isnvis(dst, &dlen, c, flag, nextc, extra); } /* * strsvis, strsvisx - visually encode characters from src into dst * * Extra is a pointer to a \0-terminated list of characters to * be encoded, too. These functions are useful e. g. to * encode strings in such a way so that they are not interpreted * by a shell. * * Dst must be 4 times the size of src to account for possible * expansion. The length of dst, not including the trailing NULL, * is returned. * * Strsvisx encodes exactly len bytes from src into dst. * This is useful for encoding a block of data. */ static int istrsnvis(char *dst, size_t *dlen, const char *csrc, int flag, const char *extra) { int c; char *start; char *nextra = NULL; const unsigned char *src = (const unsigned char *)csrc; visfun_t f; _DIAGASSERT(dst != NULL); _DIAGASSERT(src != NULL); _DIAGASSERT(extra != NULL); MAKEEXTRALIST(flag, nextra, extra); if (!nextra) { *dst = '\0'; /* can't create nextra, return "" */ return 0; } f = getvisfun(flag); for (start = dst; (c = *src++) != '\0'; /* empty */) { dst = (*f)(dst, dlen, c, flag, *src, nextra); if (dst == NULL) { errno = ENOSPC; return -1; } } free(nextra); if (dlen && *dlen == 0) { errno = ENOSPC; return -1; } *dst = '\0'; return (int)(dst - start); } int strsvis(char *dst, const char *csrc, int flag, const char *extra) { return istrsnvis(dst, NULL, csrc, flag, extra); } int strsnvis(char *dst, size_t dlen, const char *csrc, int flag, const char *extra) { return istrsnvis(dst, &dlen, csrc, flag, extra); } static int istrsnvisx(char *dst, size_t *dlen, const char *csrc, size_t len, int flag, const char *extra) { unsigned char c; char *start; char *nextra = NULL; const unsigned char *src = (const unsigned char *)csrc; visfun_t f; _DIAGASSERT(dst != NULL); _DIAGASSERT(src != NULL); _DIAGASSERT(extra != NULL); MAKEEXTRALIST(flag, nextra, extra); if (! nextra) { if (dlen && *dlen == 0) { errno = ENOSPC; return -1; } *dst = '\0'; /* can't create nextra, return "" */ return 0; } f = getvisfun(flag); for (start = dst; len > 0; len--) { c = *src++; dst = (*f)(dst, dlen, c, flag, len > 1 ? *src : '\0', nextra); if (dst == NULL) { errno = ENOSPC; return -1; } } free(nextra); if (dlen && *dlen == 0) { errno = ENOSPC; return -1; } *dst = '\0'; return (int)(dst - start); } int strsvisx(char *dst, const char *csrc, size_t len, int flag, const char *extra) { return istrsnvisx(dst, NULL, csrc, len, flag, extra); } int strsnvisx(char *dst, size_t dlen, const char *csrc, size_t len, int flag, const char *extra) { return istrsnvisx(dst, &dlen, csrc, len, flag, extra); } #endif #if !HAVE_VIS /* * vis - visually encode characters */ static char * invis(char *dst, size_t *dlen, int c, int flag, int nextc) { char *extra = NULL; unsigned char uc = (unsigned char)c; visfun_t f; _DIAGASSERT(dst != NULL); MAKEEXTRALIST(flag, extra, ""); if (! extra) { if (dlen && *dlen == 0) { errno = ENOSPC; return NULL; } *dst = '\0'; /* can't create extra, return "" */ return dst; } f = getvisfun(flag); dst = (*f)(dst, dlen, uc, flag, nextc, extra); free(extra); if (dst == NULL || (dlen && *dlen == 0)) { errno = ENOSPC; return NULL; } *dst = '\0'; return dst; } char * vis(char *dst, int c, int flag, int nextc) { return invis(dst, NULL, c, flag, nextc); } char * nvis(char *dst, size_t dlen, int c, int flag, int nextc) { return invis(dst, &dlen, c, flag, nextc); } /* * strvis, strvisx - visually encode characters from src into dst * * Dst must be 4 times the size of src to account for possible * expansion. The length of dst, not including the trailing NULL, * is returned. * * Strvisx encodes exactly len bytes from src into dst. * This is useful for encoding a block of data. */ static int istrnvis(char *dst, size_t *dlen, const char *src, int flag) { char *extra = NULL; int rv; MAKEEXTRALIST(flag, extra, ""); if (!extra) { if (dlen && *dlen == 0) { errno = ENOSPC; return -1; } *dst = '\0'; /* can't create extra, return "" */ return 0; } rv = istrsnvis(dst, dlen, src, flag, extra); free(extra); return rv; } int strvis(char *dst, const char *src, int flag) { return istrnvis(dst, NULL, src, flag); } int strnvis(char *dst, size_t dlen, const char *src, int flag) { return istrnvis(dst, &dlen, src, flag); } static int istrnvisx(char *dst, size_t *dlen, const char *src, size_t len, int flag) { char *extra = NULL; int rv; MAKEEXTRALIST(flag, extra, ""); if (!extra) { if (dlen && *dlen == 0) { errno = ENOSPC; return -1; } *dst = '\0'; /* can't create extra, return "" */ return 0; } rv = istrsnvisx(dst, dlen, src, len, flag, extra); free(extra); return rv; } int strvisx(char *dst, const char *src, size_t len, int flag) { return istrnvisx(dst, NULL, src, len, flag); } int strnvisx(char *dst, size_t dlen, const char *src, size_t len, int flag) { return istrnvisx(dst, &dlen, src, len, flag); } #endif