X-Git-Url: https://git.hcoop.net/hcoop/debian/exim4.git/blobdiff_plain/493d55f6840d04ef186778724fc67530b1600113..0baa7b9df9e8d0188307c635776394b0db691e7d:/src/demime.c diff --git a/src/demime.c b/src/demime.c deleted file mode 100644 index 887678d..0000000 --- a/src/demime.c +++ /dev/null @@ -1,1243 +0,0 @@ -/************************************************* -* Exim - an Internet mail transport agent * -*************************************************/ - -/* Copyright (c) Tom Kistner 2003-???? */ -/* License: GPL */ - -/* Code for unpacking MIME containers. Called from acl.c. */ - -#include "exim.h" -#ifdef WITH_OLD_DEMIME - -#include "demime.h" - -uschar demime_reason_buffer[1024]; -struct file_extension *file_extensions = NULL; - -int demime(uschar **listptr) { - int sep = 0; - uschar *list = *listptr; - uschar *option; - uschar option_buffer[64]; - unsigned long mbox_size; - FILE *mbox_file; - uschar defer_error_buffer[1024]; - int demime_rc = 0; - - /* reset found_extension variable */ - found_extension = NULL; - - /* try to find 1st option */ - if ((option = string_nextinlist(&list, &sep, - option_buffer, - sizeof(option_buffer))) != NULL) { - - /* parse 1st option */ - if ( (Ustrcmp(option,"false") == 0) || (Ustrcmp(option,"0") == 0) ) { - /* explicitly no demimeing */ - return FAIL; - }; - } - else { - /* no options -> no demimeing */ - return FAIL; - }; - - /* make sure the eml mbox file is spooled up */ - mbox_file = spool_mbox(&mbox_size, NULL); - - if (mbox_file == NULL) { - /* error while spooling */ - log_write(0, LOG_MAIN|LOG_PANIC, - "demime acl condition: error while creating mbox spool file"); - return DEFER; - }; - - /* call demimer if not already done earlier */ - if (!demime_ok) - demime_rc = mime_demux(mbox_file, defer_error_buffer); - - (void)fclose(mbox_file); - - if (demime_rc == DEFER) { - /* temporary failure (DEFER => DEFER) */ - log_write(0, LOG_MAIN, - "demime acl condition: %s", defer_error_buffer); - return DEFER; - }; - - /* set demime_ok to avoid unpacking again */ - demime_ok = 1; - - /* check for file extensions, if there */ - while (option != NULL) { - struct file_extension *this_extension = file_extensions; - - /* Look for the wildcard. If it is found, we always return true. - The user must then use a custom condition to evaluate demime_errorlevel */ - if (Ustrcmp(option,"*") == 0) { - found_extension = NULL; - return OK; - }; - - /* loop thru extension list */ - while (this_extension != NULL) { - if (strcmpic(option, this_extension->file_extension_string) == 0) { - /* found one */ - found_extension = this_extension->file_extension_string; - return OK; - }; - this_extension = this_extension->next; - }; - - /* grab next extension from option list */ - option = string_nextinlist(&list, &sep, - option_buffer, - sizeof(option_buffer)); - }; - - /* nothing found */ - return FAIL; -} - - -/************************************************* -* small hex_str -> integer conversion function * -*************************************************/ - -/* needed for quoted-printable -*/ - -unsigned int mime_hstr_i(uschar *cptr) { - unsigned int i, j = 0; - - while (cptr && *cptr && isxdigit(*cptr)) { - i = *cptr++ - '0'; - if (9 < i) i -= 7; - j <<= 4; - j |= (i & 0x0f); - } - - return(j); -} - - -/************************************************* -* decode quoted-printable chars * -*************************************************/ - -/* gets called when we hit a = - returns: new pointer position - result code in c: - -2 - decode error - -1 - soft line break, no char - 0-255 - char to write -*/ - -uschar *mime_decode_qp(uschar *qp_p,int *c) { - uschar hex[] = {0,0,0}; - int nan = 0; - uschar *initial_pos = qp_p; - - /* advance one char */ - qp_p++; - - REPEAT_FIRST: - if ( (*qp_p == '\t') || (*qp_p == ' ') || (*qp_p == '\r') ) { - /* tab or whitespace may follow - just ignore it, but remember - that this is not a valid hex - encoding any more */ - nan = 1; - qp_p++; - goto REPEAT_FIRST; - } - else if ( (('0' <= *qp_p) && (*qp_p <= '9')) || (('A' <= *qp_p) && (*qp_p <= 'F')) || (('a' <= *qp_p) && (*qp_p <= 'f')) ) { - /* this is a valid hex char, if nan is unset */ - if (nan) { - /* this is illegal */ - *c = -2; - return initial_pos; - } - else { - hex[0] = *qp_p; - qp_p++; - }; - } - else if (*qp_p == '\n') { - /* hit soft line break already, continue */ - *c = -1; - return qp_p; - } - else { - /* illegal char here */ - *c = -2; - return initial_pos; - }; - - if ( (('0' <= *qp_p) && (*qp_p <= '9')) || (('A' <= *qp_p) && (*qp_p <= 'F')) || (('a' <= *qp_p) && (*qp_p <= 'f')) ) { - if (hex[0] > 0) { - hex[1] = *qp_p; - /* do hex conversion */ - *c = mime_hstr_i(hex); - qp_p++; - return qp_p; - } - else { - /* huh ? */ - *c = -2; - return initial_pos; - }; - } - else { - /* illegal char */ - *c = -2; - return initial_pos; - }; - -} - - -/************************************************* -* open new dump file * -*************************************************/ - -/* open new dump file - returns: -2 soft error - or file #, FILE * in f -*/ - -int mime_get_dump_file(uschar *extension, FILE **f, uschar *info) { - uschar file_name[1024]; - int result; - unsigned int file_nr; - uschar default_extension[] = ".com"; - uschar *p; - - if (extension == NULL) - extension = default_extension; - - /* scan the proposed extension. - if it is longer than 4 chars, or - contains exotic chars, use the default extension */ - -/* if (Ustrlen(extension) > 4) { - extension = default_extension; - }; -*/ - - p = extension+1; - - while (*p != 0) { - *p = (uschar)tolower((uschar)*p); - if ( (*p < 97) || (*p > 122) ) { - extension = default_extension; - break; - }; - p++; - }; - - /* find a new file to write to */ - file_nr = 0; - do { - struct stat mystat; - - (void)string_format(file_name,1024,"%s/scan/%s/%s-%05u%s",spool_directory,message_id,message_id,file_nr,extension); - file_nr++; - if (file_nr >= MIME_SANITY_MAX_DUMP_FILES) { - /* max parts reached */ - mime_trigger_error(MIME_ERRORLEVEL_TOO_MANY_PARTS); - break; - }; - result = stat(CS file_name,&mystat); - } - while(result != -1); - - *f = modefopen(file_name,"wb+",SPOOL_MODE); - if (*f == NULL) { - /* cannot open new dump file, disk full ? -> soft error */ - (void)string_format(info, 1024,"unable to open dump file"); - return -2; - }; - - return file_nr; -} - - -/************************************************* -* Find a string in a mime header * -*************************************************/ - -/* Find a string in a mime header, and optionally fill in - the value associated with it into *value - - returns: 0 - nothing found - 1 - found param - 2 - found param + value -*/ - -int mime_header_find(uschar *header, uschar *param, uschar **value) { - uschar *needle; - - needle = strstric(header,param,FALSE); - if (needle != NULL) { - if (value != NULL) { - needle += Ustrlen(param); - if (*needle == '=') { - uschar *value_start; - uschar *value_end; - - value_start = needle + 1; - value_end = strstric(value_start,US";",FALSE); - if (value_end != NULL) { - /* allocate mem for value */ - *value = (uschar *)malloc((value_end - value_start)+1); - if (*value == NULL) - return 0; - - Ustrncpy(*value,value_start,(value_end - value_start)); - (*value)[(value_end - value_start)] = '\0'; - return 2; - }; - }; - }; - return 1; - }; - return 0; -} - - -/************************************************* -* Read a line of MIME input * -*************************************************/ -/* returns status code, one of - MIME_READ_LINE_EOF 0 - MIME_READ_LINE_OK 1 - MIME_READ_LINE_OVERFLOW 2 - - In header mode, the line will be "cooked". -*/ - -int mime_read_line(FILE *f, int mime_demux_mode, uschar *buffer, long *num_copied) { - int c = EOF; - int done = 0; - int header_value_mode = 0; - int header_open_brackets = 0; - - *num_copied = 0; - - while(!done) { - - c = fgetc(f); - if (c == EOF) break; - - /* --------- header mode -------------- */ - if (mime_demux_mode == MIME_DEMUX_MODE_MIME_HEADERS) { - - /* always skip CRs */ - if (c == '\r') continue; - - if (c == '\n') { - if ((*num_copied) > 0) { - /* look if next char is '\t' or ' ' */ - c = fgetc(f); - if (c == EOF) break; - if ( (c == '\t') || (c == ' ') ) continue; - (void)ungetc(c,f); - }; - /* end of the header, terminate with ';' */ - c = ';'; - done = 1; - }; - - /* skip control characters */ - if (c < 32) continue; - - /* skip whitespace + tabs */ - if ( (c == ' ') || (c == '\t') ) - continue; - - if (header_value_mode) { - /* --------- value mode ----------- */ - /* skip quotes */ - if (c == '"') continue; - - /* leave value mode on ';' */ - if (c == ';') { - header_value_mode = 0; - }; - /* -------------------------------- */ - } - else { - /* -------- non-value mode -------- */ - if (c == '\\') { - /* quote next char. can be used - to escape brackets. */ - c = fgetc(f); - if (c == EOF) break; - } - else if (c == '(') { - header_open_brackets++; - continue; - } - else if ((c == ')') && header_open_brackets) { - header_open_brackets--; - continue; - } - else if ( (c == '=') && !header_open_brackets ) { - /* enter value mode */ - header_value_mode = 1; - }; - - /* skip chars while we are in a comment */ - if (header_open_brackets > 0) - continue; - /* -------------------------------- */ - }; - } - /* ------------------------------------ */ - else { - /* ----------- non-header mode -------- */ - /* break on '\n' */ - if (c == '\n') - done = 1; - /* ------------------------------------ */ - }; - - /* copy the char to the buffer */ - buffer[*num_copied] = (uschar)c; - /* raise counter */ - (*num_copied)++; - - /* break if buffer is full */ - if (*num_copied > MIME_SANITY_MAX_LINE_LENGTH-1) { - done = 1; - }; - } - - /* 0-terminate */ - buffer[*num_copied] = '\0'; - - if (*num_copied > MIME_SANITY_MAX_LINE_LENGTH-1) - return MIME_READ_LINE_OVERFLOW; - else - if (c == EOF) - return MIME_READ_LINE_EOF; - else - return MIME_READ_LINE_OK; -} - - -/************************************************* -* Check for a MIME boundary * -*************************************************/ - -/* returns: 0 - no boundary found - 1 - start boundary found - 2 - end boundary found -*/ - -int mime_check_boundary(uschar *line, struct boundary *boundaries) { - struct boundary *thisboundary = boundaries; - uschar workbuf[MIME_SANITY_MAX_LINE_LENGTH+1]; - unsigned int i,j=0; - - /* check for '--' first */ - if (Ustrncmp(line,"--",2) == 0) { - - /* strip tab and space */ - for (i = 2; i < Ustrlen(line); i++) { - if ((line[i] != ' ') && (line[i] != '\t')) { - workbuf[j] = line[i]; - j++; - }; - }; - workbuf[j+1]='\0'; - - while(thisboundary != NULL) { - if (Ustrncmp(workbuf,thisboundary->boundary_string,Ustrlen(thisboundary->boundary_string)) == 0) { - if (Ustrncmp(&workbuf[Ustrlen(thisboundary->boundary_string)],"--",2) == 0) { - /* final boundary found */ - return 2; - }; - return 1; - }; - thisboundary = thisboundary->next; - }; - }; - - return 0; -} - - -/************************************************* -* Check for start of a UUENCODE block * -*************************************************/ - -/* returns 0 for no hit, - >0 for hit -*/ - -int mime_check_uu_start(uschar *line, uschar *uu_file_extension, int *has_tnef) { - - if ( (strncmpic(line,US"begin ",6) == 0)) { - uschar *uu_filename = &line[6]; - - /* skip perms, if present */ - Ustrtoul(&line[6],&uu_filename,10); - - /* advance one char */ - uu_filename++; - - /* This should be the filename. - Check if winmail.dat is present, - which indicates TNEF. */ - if (strncmpic(uu_filename,US"winmail.dat",11) == 0) { - *has_tnef = 1; - }; - - /* reverse to dot if present, - copy up to 4 chars for the extension */ - if (Ustrrchr(uu_filename,'.') != NULL) - uu_filename = Ustrrchr(uu_filename,'.'); - - return sscanf(CS uu_filename, "%4[.0-9A-Za-z]",CS uu_file_extension); - } - else { - /* nothing found */ - return 0; - }; -} - - -/************************************************* -* Decode a uu line * -*************************************************/ - -/* returns number of decoded bytes - -2 for soft errors -*/ - -int warned_about_uudec_line_sanity_1 = 0; -int warned_about_uudec_line_sanity_2 = 0; -long uu_decode_line(uschar *line, uschar **data, long line_len, uschar *info) { - uschar *p; - long num_decoded = 0; - uschar tmp_c; - uschar *work; - int uu_decoded_line_len, uu_encoded_line_len; - - /* allocate memory for data and work buffer */ - *data = (uschar *)malloc(line_len); - if (*data == NULL) { - (void)string_format(info, 1024,"unable to allocate %lu bytes",line_len); - return -2; - }; - - work = (uschar *)malloc(line_len); - if (work == NULL) { - (void)string_format(info, 1024,"unable to allocate %lu bytes",line_len); - return -2; - }; - - memcpy(work,line,line_len); - - /* First char is line length - This is microsofts way of getting it. Scary. */ - if (work[0] < 32) { - /* ignore this line */ - return 0; - } - else { - uu_decoded_line_len = uudec[work[0]]; - }; - - p = &work[1]; - - while (*p > 32) { - *p = uudec[*p]; - p++; - }; - - uu_encoded_line_len = (p - &work[1]); - p = &work[1]; - - /* check that resulting line length is a multiple of 4 */ - if ( ( uu_encoded_line_len % 4 ) != 0) { - if (!warned_about_uudec_line_sanity_1) { - mime_trigger_error(MIME_ERRORLEVEL_UU_MISALIGNED); - warned_about_uudec_line_sanity_1 = 1; - }; - return -1; - }; - - /* check that the line length matches */ - if ( ( (((uu_encoded_line_len/4)*3)-2) > uu_decoded_line_len ) || (((uu_encoded_line_len/4)*3) < uu_decoded_line_len) ) { - if (!warned_about_uudec_line_sanity_2) { - mime_trigger_error(MIME_ERRORLEVEL_UU_LINE_LENGTH); - warned_about_uudec_line_sanity_2 = 1; - }; - return -1; - }; - - while ( ((p - &work[1]) < uu_encoded_line_len) && (num_decoded < uu_decoded_line_len)) { - - /* byte 0 ---------------------- */ - if ((p - &work[1] + 1) >= uu_encoded_line_len) { - return 0; - } - - (*data)[num_decoded] = *p; - (*data)[num_decoded] <<= 2; - - tmp_c = *(p+1); - tmp_c >>= 4; - (*data)[num_decoded] |= tmp_c; - - num_decoded++; - p++; - - /* byte 1 ---------------------- */ - if ((p - &work[1] + 1) >= uu_encoded_line_len) { - return 0; - } - - (*data)[num_decoded] = *p; - (*data)[num_decoded] <<= 4; - - tmp_c = *(p+1); - tmp_c >>= 2; - (*data)[num_decoded] |= tmp_c; - - num_decoded++; - p++; - - /* byte 2 ---------------------- */ - if ((p - &work[1] + 1) >= uu_encoded_line_len) { - return 0; - } - - (*data)[num_decoded] = *p; - (*data)[num_decoded] <<= 6; - - (*data)[num_decoded] |= *(p+1); - - num_decoded++; - p+=2; - - }; - - return uu_decoded_line_len; -} - - -/************************************************* -* Decode a b64 or qp line * -*************************************************/ - -/* returns number of decoded bytes - -1 for hard errors - -2 for soft errors -*/ - -int warned_about_b64_line_length = 0; -int warned_about_b64_line_sanity = 0; -int warned_about_b64_illegal_char = 0; -int warned_about_qp_line_sanity = 0; -long mime_decode_line(int mime_demux_mode,uschar *line, uschar **data, long max_data_len, uschar *info) { - uschar *p; - long num_decoded = 0; - int offset = 0; - uschar tmp_c; - - /* allocate memory for data */ - *data = (uschar *)malloc(max_data_len); - if (*data == NULL) { - (void)string_format(info, 1024,"unable to allocate %lu bytes",max_data_len); - return -2; - }; - - if (mime_demux_mode == MIME_DEMUX_MODE_BASE64) { - /* ---------------------------------------------- */ - - /* NULL out trailing '\r' and '\n' chars */ - while (Ustrrchr(line,'\r') != NULL) { - *(Ustrrchr(line,'\r')) = '\0'; - }; - while (Ustrrchr(line,'\n') != NULL) { - *(Ustrrchr(line,'\n')) = '\0'; - }; - - /* check maximum base 64 line length */ - if (Ustrlen(line) > MIME_SANITY_MAX_B64_LINE_LENGTH ) { - if (!warned_about_b64_line_length) { - mime_trigger_error(MIME_ERRORLEVEL_B64_LINE_LENGTH); - warned_about_b64_line_length = 1; - }; - }; - - p = line; - offset = 0; - while (*(p+offset) != '\0') { - /* hit illegal char ? */ - if (b64[*(p+offset)] == 128) { - if (!warned_about_b64_illegal_char) { - mime_trigger_error(MIME_ERRORLEVEL_B64_ILLEGAL_CHAR); - warned_about_b64_illegal_char = 1; - }; - offset++; - } - else { - *p = b64[*(p+offset)]; - p++; - }; - }; - *p = 255; - - /* check that resulting line length is a multiple of 4 */ - if ( ( (p - &line[0]) % 4 ) != 0) { - if (!warned_about_b64_line_sanity) { - mime_trigger_error(MIME_ERRORLEVEL_B64_MISALIGNED); - warned_about_b64_line_sanity = 1; - }; - }; - - /* line is translated, start bit shifting */ - p = line; - num_decoded = 0; - - while(*p != 255) { - - /* byte 0 ---------------------- */ - if (*(p+1) == 255) { - break; - } - - (*data)[num_decoded] = *p; - (*data)[num_decoded] <<= 2; - - tmp_c = *(p+1); - tmp_c >>= 4; - (*data)[num_decoded] |= tmp_c; - - num_decoded++; - p++; - - /* byte 1 ---------------------- */ - if (*(p+1) == 255) { - break; - } - - (*data)[num_decoded] = *p; - (*data)[num_decoded] <<= 4; - - tmp_c = *(p+1); - tmp_c >>= 2; - (*data)[num_decoded] |= tmp_c; - - num_decoded++; - p++; - - /* byte 2 ---------------------- */ - if (*(p+1) == 255) { - break; - } - - (*data)[num_decoded] = *p; - (*data)[num_decoded] <<= 6; - - (*data)[num_decoded] |= *(p+1); - - num_decoded++; - p+=2; - - }; - return num_decoded; - /* ---------------------------------------------- */ - } - else if (mime_demux_mode == MIME_DEMUX_MODE_QP) { - /* ---------------------------------------------- */ - p = line; - - while (*p != 0) { - if (*p == '=') { - int decode_qp_result; - - p = mime_decode_qp(p,&decode_qp_result); - - if (decode_qp_result == -2) { - /* Error from decoder. p is unchanged. */ - if (!warned_about_qp_line_sanity) { - mime_trigger_error(MIME_ERRORLEVEL_QP_ILLEGAL_CHAR); - warned_about_qp_line_sanity = 1; - }; - (*data)[num_decoded] = '='; - num_decoded++; - p++; - } - else if (decode_qp_result == -1) { - /* End of the line with soft line break. - Bail out. */ - goto QP_RETURN; - } - else if (decode_qp_result >= 0) { - (*data)[num_decoded] = decode_qp_result; - num_decoded++; - }; - } - else { - (*data)[num_decoded] = *p; - num_decoded++; - p++; - }; - }; - QP_RETURN: - return num_decoded; - /* ---------------------------------------------- */ - }; - - return 0; -} - - - -/************************************************* -* Log demime errors and set mime error level * -*************************************************/ - -/* This sets the global demime_reason expansion -variable and the demime_errorlevel gauge. */ - -void mime_trigger_error(int level, uschar *format, ...) { - char *f; - va_list ap; - - if( (f = malloc(16384+23)) != NULL ) { - /* first log the incident */ - sprintf(f,"demime acl condition: "); - f+=22; - va_start(ap, format); - (void)string_vformat(US f, 16383,(char *)format, ap); - va_end(ap); - f-=22; - log_write(0, LOG_MAIN, "%s", f); - /* then copy to demime_reason_buffer if new - level is greater than old level */ - if (level > demime_errorlevel) { - demime_errorlevel = level; - Ustrcpy(demime_reason_buffer, US f); - demime_reason = demime_reason_buffer; - }; - free(f); - }; -} - -/************************************************* -* Demultiplex MIME stream. * -*************************************************/ - -/* We can handle BASE64, QUOTED-PRINTABLE, and UUENCODE. - UUENCODE does not need to have a proper - transfer-encoding header, we detect it with "begin" - - This function will report human parsable errors in - *info. - - returns DEFER -> soft error (see *info) - OK -> EOF hit, all ok -*/ - -int mime_demux(FILE *f, uschar *info) { - int mime_demux_mode = MIME_DEMUX_MODE_MIME_HEADERS; - int uu_mode = MIME_UU_MODE_OFF; - FILE *mime_dump_file = NULL; - FILE *uu_dump_file = NULL; - uschar *line; - int mime_read_line_status = MIME_READ_LINE_OK; - long line_len; - struct boundary *boundaries = NULL; - struct mime_part mime_part_p; - int has_tnef = 0; - int has_rfc822 = 0; - - /* allocate room for our linebuffer */ - line = (uschar *)malloc(MIME_SANITY_MAX_LINE_LENGTH); - if (line == NULL) { - (void)string_format(info, 1024,"unable to allocate %u bytes",MIME_SANITY_MAX_LINE_LENGTH); - return DEFER; - }; - - /* clear MIME header structure */ - memset(&mime_part_p,0,sizeof(mime_part)); - - /* ----------------------- start demux loop --------------------- */ - while (mime_read_line_status == MIME_READ_LINE_OK) { - - /* read a line of input. Depending on the mode we are in, - the returned format will differ. */ - mime_read_line_status = mime_read_line(f,mime_demux_mode,line,&line_len); - - if (mime_read_line_status == MIME_READ_LINE_OVERFLOW) { - mime_trigger_error(MIME_ERRORLEVEL_LONG_LINE); - /* despite the error, continue .. */ - mime_read_line_status = MIME_READ_LINE_OK; - continue; - } - else if (mime_read_line_status == MIME_READ_LINE_EOF) { - break; - }; - - if (mime_demux_mode == MIME_DEMUX_MODE_MIME_HEADERS) { - /* -------------- header mode --------------------- */ - - /* Check for an empty line, which is the end of the headers. - In HEADER mode, the line is returned "cooked", with the - final '\n' replaced by a ';' */ - if (line_len == 1) { - int tmp; - - /* We have reached the end of the headers. Start decoding - with the collected settings. */ - if (mime_part_p.seen_content_transfer_encoding > 1) { - mime_demux_mode = mime_part_p.seen_content_transfer_encoding; - } - else { - /* default to plain mode if no specific encoding type found */ - mime_demux_mode = MIME_DEMUX_MODE_PLAIN; - }; - - /* open new dump file */ - tmp = mime_get_dump_file(mime_part_p.extension, &mime_dump_file, info); - if (tmp < 0) { - return DEFER; - }; - - /* clear out mime_part */ - memset(&mime_part_p,0,sizeof(mime_part)); - } - else { - /* Another header to check for file extensions, - encoding type and boundaries */ - if (strncmpic(US"content-type:",line,Ustrlen("content-type:")) == 0) { - /* ---------------------------- Content-Type header ------------------------------- */ - uschar *value = line; - - /* check for message/partial MIME type and reject it */ - if (mime_header_find(line,US"message/partial",NULL) > 0) - mime_trigger_error(MIME_ERRORLEVEL_MESSAGE_PARTIAL); - - /* check for TNEF content type, remember to unpack TNEF later. */ - if (mime_header_find(line,US"application/ms-tnef",NULL) > 0) - has_tnef = 1; - - /* check for message/rfcxxx attachments */ - if (mime_header_find(line,US"message/rfc822",NULL) > 0) - has_rfc822 = 1; - - /* find the file extension, but do not fill it in - it is already set, since content-disposition has - precedence. */ - if (mime_part_p.extension == NULL) { - if (mime_header_find(line,US"name",&value) == 2) { - if (Ustrlen(value) > MIME_SANITY_MAX_FILENAME) - mime_trigger_error(MIME_ERRORLEVEL_FILENAME_LENGTH); - mime_part_p.extension = value; - mime_part_p.extension = Ustrrchr(value,'.'); - if (mime_part_p.extension == NULL) { - /* file without extension, setting - NULL will use the default extension later */ - mime_part_p.extension = NULL; - } - else { - struct file_extension *this_extension = - (struct file_extension *)malloc(sizeof(file_extension)); - - this_extension->file_extension_string = - (uschar *)malloc(Ustrlen(mime_part_p.extension)+1); - Ustrcpy(this_extension->file_extension_string, - mime_part_p.extension+1); - this_extension->next = file_extensions; - file_extensions = this_extension; - }; - }; - }; - - /* find a boundary and add it to the list, if present */ - value = line; - if (mime_header_find(line,US"boundary",&value) == 2) { - struct boundary *thisboundary; - - if (Ustrlen(value) > MIME_SANITY_MAX_BOUNDARY_LENGTH) { - mime_trigger_error(MIME_ERRORLEVEL_BOUNDARY_LENGTH); - } - else { - thisboundary = (struct boundary*)malloc(sizeof(boundary)); - thisboundary->next = boundaries; - thisboundary->boundary_string = value; - boundaries = thisboundary; - }; - }; - - if (mime_part_p.seen_content_type == 0) { - mime_part_p.seen_content_type = 1; - } - else { - mime_trigger_error(MIME_ERRORLEVEL_DOUBLE_HEADERS); - }; - /* ---------------------------------------------------------------------------- */ - } - else if (strncmpic(US"content-transfer-encoding:",line,Ustrlen("content-transfer-encoding:")) == 0) { - /* ---------------------------- Content-Transfer-Encoding header -------------- */ - - if (mime_part_p.seen_content_transfer_encoding == 0) { - if (mime_header_find(line,US"base64",NULL) > 0) { - mime_part_p.seen_content_transfer_encoding = MIME_DEMUX_MODE_BASE64; - } - else if (mime_header_find(line,US"quoted-printable",NULL) > 0) { - mime_part_p.seen_content_transfer_encoding = MIME_DEMUX_MODE_QP; - } - else { - mime_part_p.seen_content_transfer_encoding = MIME_DEMUX_MODE_PLAIN; - }; - } - else { - mime_trigger_error(MIME_ERRORLEVEL_DOUBLE_HEADERS); - }; - /* ---------------------------------------------------------------------------- */ - } - else if (strncmpic(US"content-disposition:",line,Ustrlen("content-disposition:")) == 0) { - /* ---------------------------- Content-Disposition header -------------------- */ - uschar *value = line; - - if (mime_part_p.seen_content_disposition == 0) { - mime_part_p.seen_content_disposition = 1; - - if (mime_header_find(line,US"filename",&value) == 2) { - if (Ustrlen(value) > MIME_SANITY_MAX_FILENAME) - mime_trigger_error(MIME_ERRORLEVEL_FILENAME_LENGTH); - mime_part_p.extension = value; - mime_part_p.extension = Ustrrchr(value,'.'); - if (mime_part_p.extension == NULL) { - /* file without extension, setting - NULL will use the default extension later */ - mime_part_p.extension = NULL; - } - else { - struct file_extension *this_extension = - (struct file_extension *)malloc(sizeof(file_extension)); - - this_extension->file_extension_string = - (uschar *)malloc(Ustrlen(mime_part_p.extension)+1); - Ustrcpy(this_extension->file_extension_string, - mime_part_p.extension+1); - this_extension->next = file_extensions; - file_extensions = this_extension; - }; - }; - } - else { - mime_trigger_error(MIME_ERRORLEVEL_DOUBLE_HEADERS); - }; - /* ---------------------------------------------------------------------------- */ - }; - }; /* End of header checks */ - /* ------------------------------------------------ */ - } - else { - /* -------------- non-header mode ----------------- */ - int tmp; - - if (uu_mode == MIME_UU_MODE_OFF) { - uschar uu_file_extension[5]; - /* We are not currently decoding UUENCODE - Check for possible UUENCODE start tag. */ - if (mime_check_uu_start(line,uu_file_extension,&has_tnef)) { - /* possible UUENCODING start detected. - Set unconfirmed mode first. */ - uu_mode = MIME_UU_MODE_UNCONFIRMED; - /* open new uu dump file */ - tmp = mime_get_dump_file(uu_file_extension, &uu_dump_file, info); - if (tmp < 0) { - free(line); - return DEFER; - }; - }; - } - else { - uschar *data; - long data_len = 0; - - if (uu_mode == MIME_UU_MODE_UNCONFIRMED) { - /* We are in unconfirmed UUENCODE mode. */ - - data_len = uu_decode_line(line,&data,line_len,info); - - if (data_len == -2) { - /* temp error, turn off uudecode mode */ - if (uu_dump_file != NULL) { - (void)fclose(uu_dump_file); uu_dump_file = NULL; - }; - uu_mode = MIME_UU_MODE_OFF; - return DEFER; - } - else if (data_len == -1) { - if (uu_dump_file != NULL) { - (void)fclose(uu_dump_file); uu_dump_file = NULL; - }; - uu_mode = MIME_UU_MODE_OFF; - data_len = 0; - } - else if (data_len > 0) { - /* we have at least decoded a valid byte - turn on confirmed mode */ - uu_mode = MIME_UU_MODE_CONFIRMED; - }; - } - else if (uu_mode == MIME_UU_MODE_CONFIRMED) { - /* If we are in confirmed UU mode, - check for single "end" tag on line */ - if ((strncmpic(line,US"end",3) == 0) && (line[3] < 32)) { - if (uu_dump_file != NULL) { - (void)fclose(uu_dump_file); uu_dump_file = NULL; - }; - uu_mode = MIME_UU_MODE_OFF; - } - else { - data_len = uu_decode_line(line,&data,line_len,info); - if (data_len == -2) { - /* temp error, turn off uudecode mode */ - if (uu_dump_file != NULL) { - (void)fclose(uu_dump_file); uu_dump_file = NULL; - }; - uu_mode = MIME_UU_MODE_OFF; - return DEFER; - } - else if (data_len == -1) { - /* skip this line */ - data_len = 0; - }; - }; - }; - - /* write data to dump file, if available */ - if (data_len > 0) { - if (fwrite(data,1,data_len,uu_dump_file) < data_len) { - /* short write */ - (void)string_format(info, 1024,"short write on uudecode dump file"); - free(line); - return DEFER; - }; - }; - }; - - if (mime_demux_mode != MIME_DEMUX_MODE_SCANNING) { - /* Non-scanning and Non-header mode. That means - we are currently decoding data to the dump - file. */ - - /* Check for a known boundary. */ - tmp = mime_check_boundary(line,boundaries); - if (tmp == 1) { - /* We have hit a known start boundary. - That will put us back in header mode. */ - mime_demux_mode = MIME_DEMUX_MODE_MIME_HEADERS; - if (mime_dump_file != NULL) { - /* if the attachment was a RFC822 message, recurse into it */ - if (has_rfc822) { - has_rfc822 = 0; - rewind(mime_dump_file); - mime_demux(mime_dump_file,info); - }; - - (void)fclose(mime_dump_file); mime_dump_file = NULL; - }; - } - else if (tmp == 2) { - /* We have hit a known end boundary. - That puts us into scanning mode, which will end when we hit another known start boundary */ - mime_demux_mode = MIME_DEMUX_MODE_SCANNING; - if (mime_dump_file != NULL) { - /* if the attachment was a RFC822 message, recurse into it */ - if (has_rfc822) { - has_rfc822 = 0; - rewind(mime_dump_file); - mime_demux(mime_dump_file,info); - }; - - (void)fclose(mime_dump_file); mime_dump_file = NULL; - }; - } - else { - uschar *data; - long data_len = 0; - - /* decode the line with the appropriate method */ - if (mime_demux_mode == MIME_DEMUX_MODE_PLAIN) { - /* in plain mode, just dump the line */ - data = line; - data_len = line_len; - } - else if ( (mime_demux_mode == MIME_DEMUX_MODE_QP) || (mime_demux_mode == MIME_DEMUX_MODE_BASE64) ) { - data_len = mime_decode_line(mime_demux_mode,line,&data,line_len,info); - if (data_len < 0) { - /* Error reported from the line decoder. */ - data_len = 0; - }; - }; - - /* write data to dump file */ - if (data_len > 0) { - if (fwrite(data,1,data_len,mime_dump_file) < data_len) { - /* short write */ - (void)string_format(info, 1024,"short write on dump file"); - free(line); - return DEFER; - }; - }; - - }; - } - else { - /* Scanning mode. We end up here after a end boundary. - This will usually be at the end of a message or at - the end of a MIME container. - We need to look for another start boundary to get - back into header mode. */ - if (mime_check_boundary(line,boundaries) == 1) { - mime_demux_mode = MIME_DEMUX_MODE_MIME_HEADERS; - }; - - }; - /* ------------------------------------------------ */ - }; - }; - /* ----------------------- end demux loop ----------------------- */ - - /* close files, they could still be open */ - if (mime_dump_file != NULL) - (void)fclose(mime_dump_file); - if (uu_dump_file != NULL) - (void)fclose(uu_dump_file); - - /* release line buffer */ - free(line); - - /* FIXME: release boundary buffers. - Not too much of a problem since - this instance of exim is not resident. */ - - if (has_tnef) { - uschar file_name[1024]; - /* at least one file could be TNEF encoded. - attempt to send all decoded files thru the TNEF decoder */ - - (void)string_format(file_name,1024,"%s/scan/%s",spool_directory,message_id); - /* Removed FTTB. We need to decide on TNEF inclusion */ - /* mime_unpack_tnef(file_name); */ - }; - - return 0; -} - -#endif