X-Git-Url: https://code.citadel.org/?a=blobdiff_plain;f=webcit%2Fhtml2html.c;h=a695292fe869c349f13f3f20ccd68d76b8544c2d;hb=cb5d2792dae12a5711734da4623eb9cbecf0dfef;hp=903e9696152cb7b5b8a235770246337948111381;hpb=44ce30085f81c675f9328effb744e9eb3c239c8f;p=citadel.git diff --git a/webcit/html2html.c b/webcit/html2html.c index 903e96961..a695292fe 100644 --- a/webcit/html2html.c +++ b/webcit/html2html.c @@ -1,78 +1,202 @@ /* * $Id$ - * - * Output an HTML message, modifying it slightly to make sure it plays nice + */ +/** + * \defgroup HTML2HTML Output an HTML message, modifying it slightly to make sure it plays nice * with the rest of our web framework. - * + * \ingroup WebcitHttpServer */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include +/*@{*/ #include "webcit.h" -#include "vcard.h" #include "webserver.h" -/* +/** + * \brief Strip surrounding single or double quotes from a string. + * + * \param s String to be stripped. + */ +void stripquotes(char *s) +{ + int len; + + if (!s) return; + + len = strlen(s); + if (len < 2) return; + + if ( ( (s[0] == '\"') && (s[len-1] == '\"') ) || ( (s[0] == '\'') && (s[len-1] == '\'') ) ) { + s[len-1] = 0; + strcpy(s, &s[1]); + } +} + + +/** + * \brief Check to see if a META tag has overridden the declared MIME character set. + * + * \param charset Character set name (left unchanged if we don't do anything) + * \param meta_http_equiv Content of the "http-equiv" portion of the META tag + * \param meta_content Content of the "content" portion of the META tag + */ +void extract_charset_from_meta(char *charset, char *meta_http_equiv, char *meta_content) +{ + char *ptr; + char buf[64]; + + if (!charset) return; + if (!meta_http_equiv) return; + if (!meta_content) return; + + + if (strcasecmp(meta_http_equiv, "Content-type")) return; + + ptr = strchr(meta_content, ';'); + if (!ptr) return; + + safestrncpy(buf, ++ptr, sizeof buf); + striplt(buf); + if (!strncasecmp(buf, "charset=", 8)) { + strcpy(charset, &buf[8]); + + /* + * The brain-damaged webmail program in Microsoft Exchange declares + * a charset of "unicode" when they really mean "UTF-8". GNU iconv + * treats "unicode" as an alias for "UTF-16" so we have to manually + * fix this here, otherwise messages generated in Exchange webmail + * show up as a big pile of weird characters. + */ + if (!strcasecmp(charset, "unicode")) { + strcpy(charset, "UTF-8"); + } + + } +} + + + +/** + * \brief Sanitize and enhance an HTML message for display. + * Also convert weird character sets to UTF-8 if necessary. + * + * \param supplied_charset the input charset as declared in the MIME headers */ -void output_html(void) { +void output_html(char *supplied_charset, int treat_as_wiki) { char buf[SIZ]; char *msg; char *ptr; char *msgstart; char *msgend; + char *converted_msg; + size_t converted_alloc = 0; int buffer_length = 1; int line_length = 0; int content_length = 0; + int output_length = 0; + char new_window[SIZ]; + int brak = 0; + int alevel = 0; + int scriptlevel = 0; + int script_start_pos = (-1); + int i; + int linklen; + char charset[128]; +#ifdef HAVE_ICONV + iconv_t ic = (iconv_t)(-1) ; + char *ibuf; /**< Buffer of characters to be converted */ + char *obuf; /**< Buffer for converted characters */ + size_t ibuflen; /**< Length of input buffer */ + size_t obuflen; /**< Length of output buffer */ + char *osav; /**< Saved pointer to output buffer */ +#endif + safestrncpy(charset, supplied_charset, sizeof charset); msg = strdup(""); + sprintf(new_window, "realloc() error! " - "couldn't get %d bytes: %s

\n", + ptr = realloc(msg, buffer_length); + if (ptr == NULL) { + wprintf(""); + wprintf(_("realloc() error! couldn't get %d bytes: %s"), buffer_length + 1, strerror(errno)); + wprintf("

\n"); + while (serv_getln(buf, sizeof buf), strcmp(buf, "000")) { + /** flush */ + } + free(msg); return; } + msg = ptr; strcpy(&msg[content_length], buf); content_length += line_length; strcpy(&msg[content_length], "\n"); content_length += 1; } - ptr = msg; + /** Do a first pass to isolate the message body */ + ptr = msg + 1; msgstart = msg; msgend = &msg[content_length]; while (ptr < msgend) { - /* Advance to next tag */ + /** Advance to next tag */ ptr = strchr(ptr, '<'); if ((ptr == NULL) || (ptr >= msgend)) break; ++ptr; if ((ptr == NULL) || (ptr >= msgend)) break; - /* Any of these tags cause everything up to and including + /** + * Look for META tags. Some messages (particularly in + * Asian locales) illegally declare a message's character + * set in the HTML instead of in the MIME headers. This + * is wrong but we have to work around it anyway. + */ + if (!strncasecmp(ptr, "META", 4)) { + + char *meta_start; + char *meta_end; + int meta_length; + char *meta; + char *meta_http_equiv; + char *meta_content; + char *spaceptr; + + meta_start = &ptr[4]; + meta_end = strchr(ptr, '>'); + if ((meta_end != NULL) && (meta_end <= msgend)) { + meta_length = meta_end - meta_start + 1; + meta = malloc(meta_length + 1); + safestrncpy(meta, meta_start, meta_length); + meta[meta_length] = 0; + striplt(meta); + if (!strncasecmp(meta, "HTTP-EQUIV=", 11)) { + meta_http_equiv = strdup(&meta[11]); + spaceptr = strchr(meta_http_equiv, ' '); + if (spaceptr != NULL) { + *spaceptr = 0; + meta_content = strdup(++spaceptr); + if (!strncasecmp(meta_content, "content=", 8)) { + strcpy(meta_content, &meta_content[8]); + stripquotes(meta_http_equiv); + stripquotes(meta_content); + extract_charset_from_meta(charset, + meta_http_equiv, meta_content); + } + free(meta_content); + } + free(meta_http_equiv); + } + free(meta); + } + } + + /** + * Any of these tags cause everything up to and including * the tag to be removed. */ if ( (!strncasecmp(ptr, "HTML", 4)) @@ -86,7 +210,8 @@ void output_html(void) { msgstart = ptr; } - /* Any of these tags cause everything including and following + /** + * Any of these tags cause everything including and following * the tag to be removed. */ if ( (!strncasecmp(ptr, "/HTML", 5)) @@ -99,14 +224,257 @@ void output_html(void) { ++ptr; } + if (msgstart > msg) { + strcpy(msg, msgstart); + } + + /** Convert foreign character sets to UTF-8 if necessary. */ +#ifdef HAVE_ICONV + if ( (strcasecmp(charset, "us-ascii")) + && (strcasecmp(charset, "UTF-8")) + && (strcasecmp(charset, "")) + ) { + lprintf(9, "Converting %s to UTF-8\n", charset); + ic = ctdl_iconv_open("UTF-8", charset); + if (ic == (iconv_t)(-1) ) { + lprintf(5, "%s:%d iconv_open() failed: %s\n", + __FILE__, __LINE__, strerror(errno)); + } + } + if (ic != (iconv_t)(-1) ) { + ibuf = msg; + ibuflen = content_length; + obuflen = content_length + (content_length / 2) ; + obuf = (char *) malloc(obuflen); + osav = obuf; + iconv(ic, &ibuf, &ibuflen, &obuf, &obuflen); + content_length = content_length + (content_length / 2) - obuflen; + osav[content_length] = 0; + free(msg); + msg = osav; + iconv_close(ic); + } +#endif + + /** + * At this point, the message has been stripped down to + * only the content inside the tags, and has + * been converted to UTF-8 if it was originally in a foreign + * character set. The text is also guaranteed to be null + * terminated now. + */ + + /** Now go through the message, parsing tags as necessary. */ + converted_alloc = content_length + 8192; + converted_msg = malloc(converted_alloc); + if (converted_msg == NULL) { + wprintf("Error %d: %s
%s:%s", errno, strerror(errno), __FILE__, __LINE__); + goto BAIL; + } + + strcpy(converted_msg, ""); + ptr = msg; + msgend = strchr(msg, 0); + while (ptr < msgend) { + + /** Try to sanitize the html of any rogue scripts */ + if (!strncasecmp(ptr, "= converted_alloc) { + converted_alloc += 8192; + converted_msg = realloc(converted_msg, converted_alloc); + if (converted_msg == NULL) { + abort(); + } + } + sprintf(&converted_msg[output_length], + "'))) + ) { + /* open external links to new window */ + content_length += 64; + if (content_length >= converted_alloc) { + converted_alloc += 8192; + converted_msg = realloc(converted_msg, converted_alloc); + if (converted_msg == NULL) { + abort(); + } + } + sprintf(&converted_msg[output_length], new_window); + output_length += strlen(new_window); + ptr = &ptr[8]; + } + else if ( (treat_as_wiki) && (strncasecmp(ptr, "= converted_alloc) { + converted_alloc += 8192; + converted_msg = realloc(converted_msg, converted_alloc); + if (converted_msg == NULL) { + abort(); + } + } + sprintf(&converted_msg[output_length], "') + ||(ptr[i]=='[') + ||(ptr[i]==']') + ||(ptr[i]=='"') + ||(ptr[i]=='\'') + ) linklen = i; + /* did s.b. send us an entity? */ + if (ptr[i] == '&') { + if ((ptr[i+2] ==';') || + (ptr[i+3] ==';') || + (ptr[i+5] ==';') || + (ptr[i+6] ==';') || + (ptr[i+7] ==';')) + linklen = i; + } + if (linklen > 0) break; + } + if (linklen > 0) { + char *ltreviewptr; + char *nbspreviewptr; + char linkedchar; + int len = linklen; + + len = linklen; + linkedchar = ptr[len]; + ptr[len] = '\0'; + /* spot for some subject strings tinymce tends to give us. */ + ltreviewptr = strchr(ptr, '<'); + if (ltreviewptr != NULL) { + *ltreviewptr = '\0'; + linklen = ltreviewptr - ptr; + } + + nbspreviewptr = strstr(ptr, " "); + if (nbspreviewptr != NULL) { + ///*nbspreviewptr = '\0'; + linklen = nbspreviewptr - ptr; + } + if (ltreviewptr != 0) + *ltreviewptr = '<'; + + ptr[len] = linkedchar; + + content_length += (32 + linklen); + if (content_length >= converted_alloc) { + converted_alloc += 8192; + converted_msg = realloc(converted_msg, converted_alloc); + if (converted_msg == NULL) { + abort(); + } + } + sprintf(&converted_msg[output_length], new_window); + output_length += strlen(new_window); + converted_msg[output_length] = '\"'; + converted_msg[++output_length] = 0; + for (i=0; i"); + output_length += 2; + for (i=0; i"); + output_length += 4; + } + } + else { + converted_msg[output_length] = *ptr++; + converted_msg[++output_length] = 0; + } + + /** + * We need to know when we're inside a tag, + * so we don't turn things that look like URL's into + * links, when they're already links - or image sources. + */ + if (*(ptr-1) == '<') { + ++brak; + } + if (*(ptr-1) == '>') { + --brak; + if ((scriptlevel == 0) && (script_start_pos >= 0)) { + output_length = script_start_pos; + converted_msg[output_length] = 0; + script_start_pos = (-1); + } + } + if (!strncasecmp(ptr, "", 3)) --alevel; + } - write(WC->http_sock, msgstart, strlen(msgstart)); + /** uncomment these two lines to override conversion */ + /** memcpy(converted_msg, msg, content_length); */ + /** output_length = content_length; */ - /* A little trailing vertical whitespace... */ - wprintf("

\n"); + /** Output our big pile of markup */ + client_write(converted_msg, output_length); - /* Now give back the memory */ - free(msg); +BAIL: /** A little trailing vertical whitespace... */ + wprintf("

\n"); + /** Now give back the memory */ + if (converted_msg != NULL) free(converted_msg); + if (msg != NULL) free(msg); } +/*@}*/