Bug #45855 for URI-Escape-XS: Problems with undef

After using URI::Escape::XS extensivly we have found it will cause a segmentation fault when supplied an undef value. We used this class extensively to decode encoded data used in a logging system. I have done a few changes to fix this bug and further improve performance by using a quicker hex convert technique. I have also added a further 4 tests for undef and an empty string. I have included the code below, followed by the new test. =============================================== /* * $Id: XS.xs,v 0.3 2009/01/16 06:38:52 dankogai Exp $ */ #include "EXTERN.h" #include "perl.h" #include "XSUB.h" /* #include "ppport.h" */ /* #include <URI::Escape::XS> */ # include <stdio.h> # include <stdlib.h> # include <string.h> # include <ctype.h> static char escapes[256] = /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }; static unsigned int hexconvert[256] = { 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,20,20,20,20,20,20, 20,10,11,12,13,14,15,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,10,11,12,13,14,15,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, 20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20, }; SV *encode_uri_component(SV *str){ int slen; SV *result; int i; U8 *src, *dst; int other = 0; /* * First test to see we had an undef value */ if ((str == NULL) || !SvOK(str)) return &PL_sv_undef; /* * Get length, and if zero return zero length string */ slen = SvCUR(str); /* * Allocate new sting at least 3 times length orig */ result = newSV(slen * 3 + 1); SvPOK_on(result); src = (U8 *)SvPV_nolen(str); dst = (U8 *)SvPV_nolen(result); for (i = 0; i < slen; i++){ unsigned char c = *src++; if (escapes[c]) { sprintf(dst, "%%%02X",c); dst += 3; other++; } else{ *dst++ = c; } } *dst = '\0'; /* for sure; */ SvCUR_set(result, slen + (2 * other) ); return result; } SV *decode_uri_component(SV *uri){ int slen; SV *result; U8 buf[16]; U8 *dst, *src, *bp, *odst, *srcend; unsigned int hi, lo; unsigned int a,b,c,d; /* * If undef or null return undef */ if ((uri == NULL) || !SvOK(uri)) return &PL_sv_undef; /* * Allocate result the correct len (well least as long.... */ slen = SvCUR(uri); result = newSV(slen + 1); SvPOK_on(result); dst = (U8 *)SvPV_nolen(result); odst = dst; src = (U8 *)SvPV_nolen(uri); srcend = src + slen; while (src < srcend) { unsigned char c = *src++; if (c == '%') { /* * if next digits are hex then %xx convert */ int a = hexconvert[src[0]]; int b = hexconvert[src[1]]; if ((a != 20) && (b != 20)) { *dst++ = (a << 4) | b; src += 2; continue; } /* * No is it %uxxxx ??? */ if (*src == 'u') { int a = hexconvert[src[1]]; int b = hexconvert[src[2]]; int c = hexconvert[src[3]]; int d = hexconvert[src[4]]; if ((a != 20) && (b != 20) && (c != 20) && (d != 20)) { hi = ( a << 12 ) | (b << 8) | (c << 4) | d; src += 5; if (hi < 0xD800 || 0xDFFF < hi) { bp = uvchr_to_utf8(buf, (UV)hi); strncpy(dst,buf, bp - buf); dst += bp - buf; continue; } /* * Is the range invalid ?? warn... */ if (0xDC00 <= hi) { warn("U+%04X is an invalid surrogate hi\n", hi); continue; } if ((*src == '%') && (src[1] == 'u')) { int a = hexconvert[src[2]]; int b = hexconvert[src[3]]; int c = hexconvert[src[4]]; int d = hexconvert[src[5]]; if ((a != 20) && (b != 20) && (c != 20) && (d != 20)) { lo = ( a << 12 ) | (b << 8) | (c << 4) | d; if (lo < 0xDC00 || 0xDFFF < lo){ warn("U+%04X is an invalid lo surrogate", lo); continue; } lo += 0x10000 + (hi - 0xD800) * 0x400 - 0xDC00; bp = uvchr_to_utf8(buf, (UV)lo); strncpy(dst,buf, bp - buf); dst += bp - buf; src += 6; continue; } warn("lo surrogate is missing for U+%04X", hi); continue; } warn("lo surrogate is missing for U+%04X", hi); continue; } } } *dst++ = c; } *dst = '\0'; /* for sure; */ SvCUR_set(result, (dst - odst) ); return result; } MODULE = URI::Escape::XS PACKAGE = URI::Escape::XS PROTOTYPES: ENABLE SV * encodeURIComponent(str) SV *str; CODE: RETVAL = encode_uri_component(str); OUTPUT: RETVAL SV * decodeURIComponent(str) SV *str; CODE: RETVAL = decode_uri_component(str); OUTPUT: RETVAL ================================== Here is the new test 05-null.t ===================================== #!perl -w # # $Id: 04-idn.t,v 1.2 2009/03/24 14:24:09 dankogai Exp dankogai $ # # Original as URI-1.35/t/escape.t # use URI::Escape::XS; use Test::More tests => 6; my $d; is encodeURIComponent($d) => $d, 'encodeURIComponent(null)'; is decodeURIComponent($d) => $d, 'decodeURIComponent(null)'; $d = ''; is length(encodeURIComponent($d)) => 0, 'length encodeURIComponent(\'\')'; is defined(encodeURIComponent($d)) => 1, 'defined encodeURIComponent(\'\')'; is length(decodeURIComponent($d)) => 0, 'length decodeURIComponent(\'\')'; is defined(decodeURIComponent($d)) => 1, 'defined decodeURIComponent(\'\')'; ===================================================== Yours, Karl Royer -- Research & Dev Tech Ltd Tel: +44 7860 189458 Fax: +44 870 0560360 Email: karl.royer@bigmite.co.uk Web: http://www.bigmite.co.uk/ VAT Reg. 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