webcit-ng/server/forum_view.c

   1 // The code in here feeds messages out as JSON to the client browser.  It is currently being used
   2 // for the forum view, but as we implement other views we'll probably reuse a lot of what's here.
   3 //
   4 // Copyright (c) 1996-2023 by the citadel.org team
   5 //
   6 // This program is open source software.  Use, duplication, or disclosure is subject to the GNU General Public License v3.
   7
   8 #include "webcit.h"
   9
  10 // Commands we need to send to Citadel Server before we begin rendering forum view.
  11 // These are common to flat and threaded views.
  12 void setup_for_forum_view(struct ctdlsession *c) {
  13         char buf[1024];
  14         ctdl_printf(c, "MSGP text/html|text/plain");    // Declare the MIME types we know how to render
  15         ctdl_readline(c, buf, sizeof(buf));             // Ignore the response
  16         ctdl_printf(c, "MSGP dont_decode");             // Tell the server we will decode base64/etc client-side
  17         ctdl_readline(c, buf, sizeof(buf));             // Ignore the response
  18 }
  19
  20
  21 // Convenience function for json_render_one_message()
  22 // Converts a string of comma-separated recipients into a JSON Array
  23 JsonValue *json_tokenize_recipients(const char *Key, long keylen, char *recp) {
  24         char tokbuf[1024];
  25
  26         JsonValue *j = NewJsonArray(Key, keylen);
  27         int num_recp = num_tokens(recp, ',');
  28         for (int i=0; i<num_recp; ++i) {
  29                 extract_token(tokbuf, recp, i, ',', sizeof(tokbuf));
  30                 string_trim(tokbuf);
  31                 JsonArrayAppend(j, NewJsonPlainString(HKEY("r"), tokbuf, strlen(tokbuf)));
  32         }
  33         return(j);
  34 }
  35
  36
  37 // Fetch a single message and return it in JSON format for client-side rendering
  38 void json_render_one_message(struct http_transaction *h, struct ctdlsession *c, long msgnum) {
  39         StrBuf *raw_msg = NULL;
  40         StrBuf *sanitized_msg = NULL;
  41         char buf[1024];
  42         char content_transfer_encoding[1024] = { 0 };
  43         char content_type[1024] = { 0 };
  44         char datetime[128] = { 0 };
  45         int message_originated_locally = 0;
  46
  47         setup_for_forum_view(c);
  48
  49         ctdl_printf(c, "MSG4 %ld", msgnum);
  50         ctdl_readline(c, buf, sizeof(buf));
  51         if (buf[0] != '1') {
  52                 do_404(h);
  53                 return;
  54         }
  55
  56         JsonValue *attachments = NULL;
  57
  58         JsonValue *j = NewJsonObject(HKEY(""));
  59         JsonObjectAppend(j, NewJsonNumber(HKEY("msgnum"), msgnum));
  60
  61         while ((ctdl_readline(c, buf, sizeof(buf)) >= 0) && (strcmp(buf, "text")) && (strcmp(buf, "000"))) {
  62                 utf8ify_rfc822_string(&buf[5]);
  63
  64                 // citadel header parsing here
  65                 if (!strncasecmp(buf, "from=", 5)) {
  66                         JsonObjectAppend(j, NewJsonPlainString(HKEY("from"), &buf[5], -1));
  67                 }
  68                 else if (!strncasecmp(buf, "rfca=", 5)) {
  69                         JsonObjectAppend(j, NewJsonPlainString(HKEY("rfca"), &buf[5], -1));
  70                 }
  71                 else if (!strncasecmp(buf, "time=", 5)) {
  72                         JsonObjectAppend(j, NewJsonNumber(HKEY("time"), atol(&buf[5])));
  73                 }
  74                 else if (!strncasecmp(buf, "locl=", 5)) {
  75                         message_originated_locally = 1;
  76                 }
  77                 else if (!strncasecmp(buf, "subj=", 5)) {
  78                         JsonObjectAppend(j, NewJsonPlainString(HKEY("subj"), &buf[5], -1));
  79                 }
  80                 else if (!strncasecmp(buf, "msgn=", 5)) {
  81                         JsonObjectAppend(j, NewJsonPlainString(HKEY("msgn"), &buf[5], -1));
  82                 }
  83                 else if (!strncasecmp(buf, "wefw=", 5)) {
  84                         JsonObjectAppend(j, NewJsonPlainString(HKEY("wefw"), &buf[5], -1));
  85                 }
  86                 else if (!strncasecmp(buf, "rcpt=", 5)) {
  87                         JsonObjectAppend(j, json_tokenize_recipients(HKEY("rcpt"), &buf[5]));
  88                 }
  89                 else if (!strncasecmp(buf, "cccc=", 5)) {
  90                         JsonObjectAppend(j, json_tokenize_recipients(HKEY("cccc"), &buf[5]));
  91                 }
  92                 else if (!strncasecmp(buf, "part=", 5)) {
  93                         if (attachments == NULL) {
  94                                 attachments = NewJsonArray(HKEY("part"));
  95                         }
  96                         JsonValue *part = NewJsonObject(HKEY(""));
  97                         char tokbuf[1024];
  98                         extract_token(tokbuf, &buf[5], 0, '|', sizeof tokbuf);
  99                         JsonObjectAppend(part, NewJsonPlainString(HKEY("name"), tokbuf, -1));
 100                         extract_token(tokbuf, &buf[5], 1, '|', sizeof tokbuf);
 101                         JsonObjectAppend(part, NewJsonPlainString(HKEY("filename"), tokbuf, -1));
 102                         extract_token(tokbuf, &buf[5], 2, '|', sizeof tokbuf);
 103                         JsonObjectAppend(part, NewJsonPlainString(HKEY("partnum"), tokbuf, -1));
 104                         extract_token(tokbuf, &buf[5], 3, '|', sizeof tokbuf);
 105                         JsonObjectAppend(part, NewJsonPlainString(HKEY("disp"), tokbuf, -1));
 106                         extract_token(tokbuf, &buf[5], 4, '|', sizeof tokbuf);
 107                         JsonObjectAppend(part, NewJsonPlainString(HKEY("type"), tokbuf, -1));
 108                         JsonObjectAppend(part, NewJsonNumber(HKEY("len"), extract_long(&buf[5], 5)));
 109                         extract_token(tokbuf, &buf[5], 6, '|', sizeof tokbuf);
 110                         JsonObjectAppend(part, NewJsonPlainString(HKEY("id"), tokbuf, -1));
 111                         extract_token(tokbuf, &buf[5], 7, '|', sizeof tokbuf);
 112                         JsonObjectAppend(part, NewJsonPlainString(HKEY("charset"), tokbuf, -1));
 113                         JsonArrayAppend(attachments, part);
 114                 }
 115                 else {
 116                         // unhandled header
 117                 }
 118         }
 119         JsonObjectAppend(j, NewJsonNumber(HKEY("locl"), message_originated_locally));
 120         if (attachments != NULL) {
 121                 JsonObjectAppend(j, attachments);
 122         }
 123
 124         if (!strcmp(buf, "text")) {
 125                 while ((ctdl_readline(c, buf, sizeof(buf)) >= 0) && (strcmp(buf, "")) && (strcmp(buf, "000"))) {
 126                         // rfc822 header parsing here
 127                         if (!strncasecmp(buf, "Content-transfer-encoding:", 26)) {
 128                                 strcpy(content_transfer_encoding, &buf[26]);
 129                                 string_trim(content_transfer_encoding);
 130                         }
 131                         if (!strncasecmp(buf, "Content-type:", 13)) {
 132                                 strcpy(content_type, &buf[13]);
 133                                 string_trim(content_type);
 134                         }
 135                 }
 136                 if (!strcmp(buf, "000")) {              // if we have an empty message, don't try to read further
 137                         raw_msg = NULL;
 138                 }
 139                 else {
 140                         raw_msg = ctdl_readtextmsg(c);
 141                 }
 142         }
 143         else {
 144                 raw_msg = NULL;
 145         }
 146
 147         if (raw_msg) {
 148                 // These are the encodings we know how to handle.  Decode in-place.
 149
 150                 if (!strcasecmp(content_transfer_encoding, "base64")) {
 151                         StrBufDecodeBase64(raw_msg);
 152                 }
 153                 if (!strcasecmp(content_transfer_encoding, "quoted-printable")) {
 154                         StrBufDecodeQP(raw_msg);
 155                 }
 156
 157                 // At this point, raw_msg contains the decoded message.
 158                 // Now run through the renderers we have available.
 159
 160                 if (!strncasecmp(content_type, "text/html", 9)) {
 161                         sanitized_msg = html2html("UTF-8", 0, c->room, msgnum, raw_msg);
 162                 }
 163                 else if (!strncasecmp(content_type, "text/plain", 10)) {
 164                         sanitized_msg = text2html("UTF-8", 0, c->room, msgnum, raw_msg);
 165                 }
 166                 else if (!strncasecmp(content_type, "text/x-citadel-variformat", 25)) {
 167                         sanitized_msg = variformat2html(raw_msg);
 168                 }
 169                 else {
 170                         sanitized_msg = NewStrBufPlain(HKEY("<i>No renderer for this content type</i><br>"));
 171                         syslog(LOG_WARNING, "forum_view: no renderer for content type %s", content_type);
 172                 }
 173                 FreeStrBuf(&raw_msg);
 174
 175                 // If sanitized_msg is not NULL, we have rendered the message and can output it.
 176                 if (sanitized_msg) {
 177                         JsonObjectAppend(j, NewJsonString(HKEY("text"), sanitized_msg, NEWJSONSTRING_SMASHBUF));
 178                 }
 179                 else {
 180                         syslog(LOG_WARNING, "forum_view: message %ld of content type %s converted to NULL", msgnum, content_type);
 181                 }
 182         }
 183
 184         StrBuf *sj = NewStrBuf();
 185         SerializeJson(sj, j, 1);        // '1' == free the source object
 186
 187         add_response_header(h, strdup("Content-type"), strdup("application/json"));
 188         h->response_code = 200;
 189         h->response_string = strdup("OK");
 190         h->response_body_length = StrLength(sj);
 191         h->response_body = SmashStrBuf(&sj);
 192 }