/*
- * mime_parser.c
+ * $Id$
+ *
+ * This is the MIME parser for Citadel. Sometimes it actually works.
+ *
+ * Copyright (c) 1998-2003 by Art Cancro
+ * This code is distributed under the terms of the GNU General Public License.
*
- * This is a really bad attempt at writing a parser to handle multipart
- * messages -- in the case of WebCit, a form containing uploaded files.
*/
+#include <ctype.h>
#include <stdlib.h>
+#ifdef HAVE_UNISTD_H
#include <unistd.h>
+#endif
#include <stdio.h>
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
#include <signal.h>
#include <sys/types.h>
-#include <ctype.h>
+#include <sys/wait.h>
+#include <sys/socket.h>
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
#include <string.h>
+#include <pwd.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <pthread.h>
+#include <signal.h>
#include "webcit.h"
-#include "child.h"
+#include "webserver.h"
+
+#include "mime_parser.h"
+
+
+void extract_key(char *target, char *source, char *key)
+{
+ int a, b;
+
+ strcpy(target, source);
+ for (a = 0; a < strlen(target); ++a) {
+ if ((!strncasecmp(&target[a], key, strlen(key)))
+ && (target[a + strlen(key)] == '=')) {
+ strcpy(target, &target[a + strlen(key) + 1]);
+ if (target[0] == 34)
+ strcpy(target, &target[1]);
+ for (b = 0; b < strlen(target); ++b)
+ if (target[b] == 34)
+ target[b] = 0;
+ return;
+ }
+ }
+ strcpy(target, "");
+}
+
/*
- * Take a part, figure out its length, and do something with it
+ * For non-multipart messages, we need to generate a quickie partnum of "1"
+ * to return to callback functions. Some callbacks demand it.
*/
-void process_part(char *content, int part_length) {
- FILE *fp;
- char filename[256];
- static char partno = 0;
- char *start;
- char buf[512];
- int crlf = 0; /* set to 1 for crlf-style newlines */
- int actual_length;
-
- fprintf(stderr, "MIME: process_part() called with a length o' %d\n",
- part_length);
-
- /* Strip off any leading blank lines. */
- start = content;
- while ((!strncmp(start, "\r", 1)) || (!strncmp(start, "\n", 1))) {
- ++start;
- --part_length;
+char *fixed_partnum(char *supplied_partnum) {
+ if (supplied_partnum == NULL) return "1";
+ if (strlen(supplied_partnum)==0) return "1";
+ return supplied_partnum;
+}
+
+
+
+/*
+ * Convert "quoted-printable" to binary. Returns number of bytes decoded.
+ */
+int CtdlDecodeQuotedPrintable(char *decoded, char *encoded, int sourcelen) {
+ char buf[SIZ];
+ int buf_length = 0;
+ int soft_line_break = 0;
+ int ch;
+ int decoded_length = 0;
+ int i;
+
+ decoded[0] = 0;
+ decoded_length = 0;
+ buf[0] = 0;
+ buf_length = 0;
+
+ for (i = 0; i < sourcelen; ++i) {
+
+ buf[buf_length++] = encoded[i];
+
+ if ( (encoded[i] == '\n')
+ || (encoded[i] == 0)
+ || (i == (sourcelen-1)) ) {
+ buf[buf_length++] = 0;
+
+ /*** begin -- process one line ***/
+
+ if (buf[strlen(buf)-1] == '\n') {
+ buf[strlen(buf)-1] = 0;
+ }
+ if (buf[strlen(buf)-1] == '\r') {
+ buf[strlen(buf)-1] = 0;
+ }
+ while (isspace(buf[strlen(buf)-1])) {
+ buf[strlen(buf)-1] = 0;
+ }
+ soft_line_break = 0;
+
+ while (strlen(buf) > 0) {
+ if (!strcmp(buf, "=")) {
+ soft_line_break = 1;
+ strcpy(buf, "");
+ } else if ((strlen(buf)>=3) && (buf[0]=='=')) {
+ sscanf(&buf[1], "%02x", &ch);
+ decoded[decoded_length++] = ch;
+ strcpy(buf, &buf[3]);
+ } else {
+ decoded[decoded_length++] = buf[0];
+ strcpy(buf, &buf[1]);
+ }
+ }
+ if (soft_line_break == 0) {
+ decoded[decoded_length++] = '\r';
+ decoded[decoded_length++] = '\n';
+ }
+ buf_length = 0;
+ /*** end -- process one line ***/
}
+ }
- /* At this point all we have left is the headers and the content. */
- do {
- strcpy(buf, "");
- do {
- buf[strlen(buf)+1] = 0;
- strncpy(&buf[strlen(buf)], start, 1);
- ++start;
- --part_length;
- } while((buf[strlen(buf)-1] != 10) && (part_length>0));
- if (part_length <= 0) return;
- buf[strlen(buf)-1] = 0;
- if (buf[strlen(buf)-1]==13) {
- buf[strlen(buf)-1] = 0;
- crlf = 1;
+ decoded[decoded_length++] = 0;
+ return(decoded_length);
+}
+
+/*
+ * Given a message or message-part body and a length, handle any necessary
+ * decoding and pass the request up the stack.
+ */
+void mime_decode(char *partnum,
+ char *part_start, size_t length,
+ char *content_type, char *encoding,
+ char *disposition,
+ char *name, char *filename,
+ void (*CallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+ void (*PreMultiPartCallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+ void (*PostMultiPartCallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+ void *userdata,
+ int dont_decode
+)
+{
+
+ char *decoded;
+ size_t bytes_decoded = 0;
+
+ /* Some encodings aren't really encodings */
+ if (!strcasecmp(encoding, "7bit"))
+ strcpy(encoding, "");
+ if (!strcasecmp(encoding, "8bit"))
+ strcpy(encoding, "");
+ if (!strcasecmp(encoding, "binary"))
+ strcpy(encoding, "");
+
+ /* If this part is not encoded, send as-is */
+ if ( (strlen(encoding) == 0) || (dont_decode)) {
+ if (CallBack != NULL) {
+ CallBack(name, filename, fixed_partnum(partnum),
+ disposition, part_start,
+ content_type, length, encoding, userdata);
}
- fprintf(stderr, "MIME: <%s>\n", buf);
- } while (strlen(buf)>0);
- fprintf(stderr, "MIME: done processing headers\n");
-
- if (crlf) actual_length = part_length - 2;
- else actual_length = part_length - 1;
+ return;
+ }
- sprintf(filename, "content.%04x.%04x", getpid(), ++partno);
- fp = fopen(filename, "wb");
- fwrite(start, actual_length, 1, fp);
- fclose(fp);
+ if ((strcasecmp(encoding, "base64"))
+ && (strcasecmp(encoding, "quoted-printable"))) {
+ return;
+ }
+ /*
+ * Allocate a buffer for the decoded data. The output buffer is the
+ * same size as the input buffer; this assumes that the decoded data
+ * will never be larger than the encoded data. This is a safe
+ * assumption with base64, uuencode, and quoted-printable.
+ */
+ decoded = mallok(length+2048);
+ if (decoded == NULL) {
+ return;
}
-
+ if (!strcasecmp(encoding, "base64")) {
+ bytes_decoded = CtdlDecodeBase64(decoded, part_start, length);
+ }
+ else if (!strcasecmp(encoding, "quoted-printable")) {
+ bytes_decoded = CtdlDecodeQuotedPrintable(decoded,
+ part_start, length);
+ }
+
+ if (bytes_decoded > 0) if (CallBack != NULL) {
+ CallBack(name, filename, fixed_partnum(partnum),
+ disposition, decoded,
+ content_type, bytes_decoded, "binary", userdata);
+ }
+
+ phree(decoded);
+}
+
/*
- * Main function of parser
+ * Break out the components of a multipart message
+ * (This function expects to be fed HEADERS + CONTENT)
+ * Note: NULL can be supplied as content_end; in this case, the message is
+ * considered to have ended when the parser encounters a 0x00 byte.
*/
-void mime_parser(char *content, int ContentLength, char *ContentType) {
- char boundary[256];
- char endary[256];
- int have_boundary = 0;
- int a;
+void the_mime_parser(char *partnum,
+ char *content_start, char *content_end,
+ void (*CallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+ void (*PreMultiPartCallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+ void (*PostMultiPartCallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+ void *userdata,
+ int dont_decode
+)
+{
+
char *ptr;
- char *beginning;
- int bytes_processed = 0;
- int part_length;
-
- fprintf(stderr, "MIME: ContentLength: %d, ContentType: %s\n",
- ContentLength, ContentType);
-
- /* Figure out what the boundary is */
- strcpy(boundary, ContentType);
- for (a=0; a<strlen(boundary); ++a) {
- if (!strncasecmp(&boundary[a], "boundary=", 9)) {
- boundary[0]='-';
- boundary[1]='-';
- strcpy(&boundary[2], &boundary[a+9]);
- have_boundary = 1;
- a = 0;
+ char *part_start, *part_end = NULL;
+ char buf[SIZ];
+ char *header;
+ char *boundary;
+ char *startary;
+ char *endary;
+ char *content_type;
+ size_t content_length;
+ char *encoding;
+ char *disposition;
+ char *name = NULL;
+ char *content_type_name;
+ char *content_disposition_name;
+ char *filename;
+ int is_multipart;
+ int part_seq = 0;
+ int i;
+ size_t length;
+ char nested_partnum[SIZ];
+
+ ptr = content_start;
+ content_length = 0;
+
+ boundary = mallok(SIZ);
+ memset(boundary, 0, SIZ);
+
+ startary = mallok(SIZ);
+ memset(startary, 0, SIZ);
+
+ endary = mallok(SIZ);
+ memset(endary, 0, SIZ);
+
+ header = mallok(SIZ);
+ memset(header, 0, SIZ);
+
+ content_type = mallok(SIZ);
+ memset(content_type, 0, SIZ);
+
+ encoding = mallok(SIZ);
+ memset(encoding, 0, SIZ);
+
+ content_type_name = mallok(SIZ);
+ memset(content_type_name, 0, SIZ);
+
+ content_disposition_name = mallok(SIZ);
+ memset(content_disposition_name, 0, SIZ);
+
+ filename = mallok(SIZ);
+ memset(filename, 0, SIZ);
+
+ disposition = mallok(SIZ);
+ memset(disposition, 0, SIZ);
+
+ /* If the caller didn't supply an endpointer, generate one by measure */
+ if (content_end == NULL) {
+ content_end = &content_start[strlen(content_start)];
+ }
+
+ /* Learn interesting things from the headers */
+ strcpy(header, "");
+ do {
+ ptr = memreadline(ptr, buf, SIZ);
+ if (ptr >= content_end) {
+ goto end_parser;
+ }
+
+ for (i = 0; i < strlen(buf); ++i)
+ if (isspace(buf[i]))
+ buf[i] = ' ';
+ if (!isspace(buf[0])) {
+ if (!strncasecmp(header, "Content-type: ", 14)) {
+ strcpy(content_type, &header[14]);
+ extract_key(content_type_name, content_type, "name");
+ /* Deal with weird headers */
+ if (strchr(content_type, ' '))
+ *(strchr(content_type, ' ')) = '\0';
+ if (strchr(content_type, ';'))
+ *(strchr(content_type, ';')) = '\0';
+ }
+ if (!strncasecmp(header, "Content-Disposition: ", 21)) {
+ strcpy(disposition, &header[21]);
+ extract_key(content_disposition_name, disposition, "name");
+ extract_key(filename, disposition, "filename");
}
- if ((boundary[a]==13) || (boundary[a]==10)) {
- boundary[a] = 0;
+ if (!strncasecmp(header, "Content-length: ", 16)) {
+ content_length = (size_t) atol(&header[16]);
}
+ if (!strncasecmp(header,
+ "Content-transfer-encoding: ", 27))
+ strcpy(encoding, &header[27]);
+ if (strlen(boundary) == 0)
+ extract_key(boundary, header, "boundary");
+ strcpy(header, "");
}
+ if ((strlen(header) + strlen(buf) + 2) < SIZ)
+ strcat(header, buf);
+ } while ((strlen(buf) > 0) && (*ptr != 0));
- /* We can't process multipart messages without a boundary. */
- if (have_boundary == 0) return;
- strcpy(endary, boundary);
- strcat(endary, "--");
- fprintf(stderr, "MIME: boundary is %s\n", boundary);
- fprintf(stderr, "MIME: endary is %s\n", endary);
+ if (strchr(disposition, ';'))
+ *(strchr(disposition, ';')) = '\0';
+ striplt(disposition);
+ if (strchr(content_type, ';'))
+ *(strchr(content_type, ';')) = '\0';
+ striplt(content_type);
- ptr = content;
-
- /* Seek to the beginning of the next boundary */
- while (bytes_processed < ContentLength) {
- /* && (strncasecmp(ptr, boundary, strlen(boundary))) ) { */
+ if (strlen(boundary) > 0) {
+ is_multipart = 1;
+ } else {
+ is_multipart = 0;
+ }
- if (strncasecmp(ptr, boundary, strlen(boundary))) {
- ++ptr;
- ++bytes_processed;
- }
+ /* If this is a multipart message, then recursively process it */
+ part_start = NULL;
+ if (is_multipart) {
- /* See if we're at the end */
- if (!strncasecmp(ptr, endary, strlen(endary))) {
- fprintf(stderr, "MIME: the end.\n");
- return;
- }
+ /* Tell the client about this message's multipartedness */
+ if (PreMultiPartCallBack != NULL) {
+ PreMultiPartCallBack("", "", partnum, "",
+ NULL, content_type,
+ 0, encoding, userdata);
+ }
- /* Seek to the end of the boundary string */
- if (!strncasecmp(ptr, boundary, strlen(boundary))) {
- fprintf(stderr, "MIME: founda bounda\n");
- while ( (bytes_processed < ContentLength)
- && (strncasecmp(ptr, "\n", 1)) ) {
- ++ptr;
- ++bytes_processed;
+ /* Figure out where the boundaries are */
+ snprintf(startary, SIZ, "--%s", boundary);
+ snprintf(endary, SIZ, "--%s--", boundary);
+ do {
+ if ( (!strncasecmp(ptr, startary, strlen(startary)))
+ || (!strncasecmp(ptr, endary, strlen(endary))) ) {
+ if (part_start != NULL) {
+ if (strlen(partnum) > 0) {
+ snprintf(nested_partnum,
+ sizeof nested_partnum,
+ "%s.%d", partnum,
+ ++part_seq);
+ }
+ else {
+ snprintf(nested_partnum,
+ sizeof nested_partnum,
+ "%d", ++part_seq);
+ }
+ the_mime_parser(nested_partnum,
+ part_start, part_end,
+ CallBack,
+ PreMultiPartCallBack,
+ PostMultiPartCallBack,
+ userdata,
+ dont_decode);
}
- beginning = ptr;
- part_length = 0;
- while ( (bytes_processed < ContentLength)
- && (strncasecmp(ptr, boundary, strlen(boundary))) ) {
+ ptr = memreadline(ptr, buf, SIZ);
+ part_start = ptr;
+ }
+ else {
+ part_end = ptr;
++ptr;
- ++bytes_processed;
- ++part_length;
+ }
+ /* If we pass out of scope in the MIME multipart (by
+ * hitting the end boundary), force the pointer out
+ * of scope so this loop ends.
+ */
+ if (ptr < content_end) {
+ if (!strcasecmp(ptr, endary)) {
+ ptr = content_end++;
}
- process_part(beginning, part_length);
- /* Back off so we can see the next boundary */
- --ptr;
- --bytes_processed;
}
+ } while (ptr <= content_end);
+ if (PostMultiPartCallBack != NULL) {
+ PostMultiPartCallBack("", "", partnum, "", NULL,
+ content_type, 0, encoding, userdata);
+ }
+ goto end_parser;
+ }
+
+ /* If it's not a multipart message, then do something with it */
+ if (!is_multipart) {
+ part_start = ptr;
+ length = 0;
+ while (ptr < content_end) {
+ ++ptr;
+ ++length;
+ }
+ part_end = content_end;
+ /* fix an off-by-one error */
+ --part_end;
+ --length;
+
+ /* Truncate if the header told us to */
+ if ( (content_length > 0) && (length > content_length) ) {
+ length = content_length;
+ }
+
+ /* Sometimes the "name" field is tacked on to Content-type,
+ * and sometimes it's tacked on to Content-disposition. Use
+ * whichever one we have.
+ */
+ if (strlen(content_disposition_name) > strlen(content_type_name)) {
+ name = content_disposition_name;
+ }
+ else {
+ name = content_type_name;
}
+
+ mime_decode(partnum,
+ part_start, length,
+ content_type, encoding, disposition,
+ name, filename,
+ CallBack, NULL, NULL,
+ userdata, dont_decode);
}
+
+end_parser: /* free the buffers! end the oppression!! */
+ phree(boundary);
+ phree(startary);
+ phree(endary);
+ phree(header);
+ phree(content_type);
+ phree(encoding);
+ phree(content_type_name);
+ phree(content_disposition_name);
+ phree(filename);
+ phree(disposition);
+}
+
+
+
+/*
+ * Entry point for the MIME parser.
+ * (This function expects to be fed HEADERS + CONTENT)
+ * Note: NULL can be supplied as content_end; in this case, the message is
+ * considered to have ended when the parser encounters a 0x00 byte.
+ */
+void mime_parser(char *content_start,
+ char *content_end,
+
+ void (*CallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+
+ void (*PreMultiPartCallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+
+ void (*PostMultiPartCallBack)
+ (char *cbname,
+ char *cbfilename,
+ char *cbpartnum,
+ char *cbdisp,
+ void *cbcontent,
+ char *cbtype,
+ size_t cblength,
+ char *cbencoding,
+ void *cbuserdata),
+
+ void *userdata,
+ int dont_decode
+)
+{
+
+ the_mime_parser("", content_start, content_end,
+ CallBack,
+ PreMultiPartCallBack,
+ PostMultiPartCallBack,
+ userdata, dont_decode);
+}
+