/* * MIME mail decoding. * * This module contains decoding routines for converting * quoted-printable data into pure 8-bit data, in MIME * formatted messages. * * By Henrik Storner * * Configuration file support for fetchmail 4.3.8 by * Frank Damgaard * * For license terms, see the file COPYING in this directory. */ #include "config.h" #include #include #include #include #include "fetchmail.h" #include "i18n.h" static unsigned char unhex(unsigned char c) { if ((c >= '0') && (c <= '9')) return (c - '0'); else if ((c >= 'A') && (c <= 'F')) return (c - 'A' + 10); else if ((c >= 'a') && (c <= 'f')) return (c - 'a' + 10); else return 16; /* invalid hex character */ } static int qp_char(unsigned char c1, unsigned char c2, char *c_out) { c1 = unhex(c1); c2 = unhex(c2); if ((c1 > 15) || (c2 > 15)) return 1; else { *c_out = 16*c1+c2; return 0; } } /* * Routines to decode MIME QP-encoded headers, as per RFC 2047. */ /* States of the decoding state machine */ #define S_COPY_PLAIN 0 /* Just copy, but watch for the QP flag */ #define S_SKIP_MIMEINIT 1 /* Get the encoding, and skip header */ #define S_COPY_MIME 2 /* Decode a sequence of coded characters */ static const char MIMEHDR_INIT[] = "=?"; /* Start of coded sequence */ static const char MIMEHDR_END[] = "?="; /* End of coded sequence */ void UnMimeHeader(char *hdr) { /* Decode a buffer containing data encoded according to RFC * 2047. This only handles content-transfer-encoding; conversion * between character sets is not implemented. In other words: We * assume the charsets used can be displayed by your mail program * without problems. */ /* Note: Decoding is done "in-situ", i.e. without using an * additional buffer for temp. storage. This is possible, since the * decoded string will always be shorter than the encoded string, * due to the encoding scheme. */ int state = S_COPY_PLAIN; char *p_in, *p_out, *p; char enc = '\0'; /* initialization pacifies -Wall */ int i; /* Speed up in case this is not a MIME-encoded header */ p = strstr(hdr, MIMEHDR_INIT); if (p == NULL) return; /* No MIME header */ /* Loop through the buffer. * p_in : Next char to be processed. * p_out: Where to put the next processed char * enc : Encoding used (usually, 'q' = quoted-printable) */ for (p_out = p_in = hdr; (*p_in); ) { switch (state) { case S_COPY_PLAIN: p = strstr(p_in, MIMEHDR_INIT); if (p == NULL) { /* * No more coded data in buffer, * just move remainder into place. */ i = strlen(p_in); /* How much left */ memmove(p_out, p_in, i); p_in += i; p_out += i; } else { /* MIME header init found at location p */ if (p > p_in) { /* There are some uncoded chars at the beginning. */ i = (p - p_in); memmove(p_out, p_in, i); p_out += i; } p_in = (p + 2); state = S_SKIP_MIMEINIT; } break; case S_SKIP_MIMEINIT: /* Mime type definition: "charset?encoding?" */ p = strchr(p_in, '?'); if (p != NULL) { /* p_in .. (p-1) holds the charset */ /* *(p+1) is the transfer encoding, *(p+2) must be a '?' */ if (*(p+2) == '?') { enc = tolower((unsigned char)*(p+1)); p_in = p+3; state = S_COPY_MIME; } else state = S_COPY_PLAIN; } else state = S_COPY_PLAIN; /* Invalid data */ break; case S_COPY_MIME: p = strstr(p_in, MIMEHDR_END); /* Find end of coded data */ if (p == NULL) p = p_in + strlen(p_in); for (; (p_in < p); ) { /* Decode all encoded data */ if (enc == 'q') { if (*p_in == '=') { /* Decode one char qp-coded at (p_in+1) and (p_in+2) */ if (qp_char(*(p_in+1), *(p_in+2), p_out) == 0) p_in += 3; else { /* Invalid QP data - pass through unchanged. */ *p_out = *p_in; p_in++; } } else if (*p_in == '_') { /* * RFC 2047: '_' inside encoded word represents 0x20. * NOT a space - always the value 0x20. */ *p_out = 0x20; p_in++; } else { /* Copy unchanged */ *p_out = *p_in; p_in++; } p_out++; } else if (enc == 'b') { /* Decode base64 encoded data */ char delimsave; int decoded_count; delimsave = *p; *p = '\r'; decoded_count = from64tobits(p_out, p_in, 0); *p = delimsave; if (decoded_count > 0) p_out += decoded_count; p_in = p; } else { /* Copy unchanged */ *p_out = *p_in; p_in++; p_out++; } } if (*p_in) p_in += 2; /* Skip the MIMEHDR_END delimiter */ /* * We've completed decoding one encoded sequence. But another * may follow immediately, in which case whitespace before the * new MIMEHDR_INIT delimiter must be discarded. * See if that is the case */ p = strstr(p_in, MIMEHDR_INIT); state = S_COPY_PLAIN; if (p != NULL) { /* * There is more MIME data later on. Is there *
-------------------------------------------------------------------------------

                         - GetMail - GotMail -

             1999 by Thomas Nesges <ThomaNesges@TNT-Computer.de>

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------
Installation:
-------------------------------------------------------------------------------
The Installation is as simple as it could be.  Just create the directory
/usr/local/gotmail and copy all files to it. Ready.

If you decide to choose an other directory to copy the files to, don't forget
to change the path in the scripts.

-------------------------------------------------------------------------------
Usage:
-------------------------------------------------------------------------------
GetMail starts with: getmail <option>

options:
 clear  - stops fetchmail and kills the logfile
 fetch  - starts fetchmail
 got    - starts gotmail
 goth   - starts gotmail html
 send   - sends all mail from the mailqueue
 status - tails the logfile
 start  - starts fetchmail and tails the logfile
 stop   - stops fetchmail
 -v     - prints GetMails version number

GotMail can be startet without any parameters. It then prints a statistic
on the console. The only parameters so far are:

 html   - prints the output to an html file specified in gotmail.conf
 -v     - prints GotMails version number

-------------------------------------------------------------------------------
Configuration
-------------------------------------------------------------------------------
GotMail is configured by a file named gotmail.conf either in the user's home
dir, in /etc or in /usr/local/gotmail. gotmail.conf itself is a shell script.
It just exports some variables to the environment. So it's syntax is like this:

 export <OPTION>=<VALUE>

Remember not to put spaces between <OPTION>=<VALUE> !!
You have the folllowing options:
 
  GOTM_ERR	yes|no		print error messages?
  GOTM_MSG	yes|no		print mail stats?
  GOTM_TIM	yes|no		print start/stop stats?
  GOTM_HED	yes|no		print a header?

 Special HTML options:
  GOTM_BGCOL	hex color	backgroundcolor
  GOTM_TXCOL	hex color	textcolor
  GOTM_ERRCOL	hex color	color of error messages
  GOTM_TIMCOL	hex color	color of start/stop stats
  GOTM_MSGCOL	hex color	color of mail stats
  GOTM_HTMLFILE	filename	filename for html output
-------------------------------------------------------------------------------
generated by cgit v1.2.3 (git 2.39.1) at 2026-01-10 05:25:48 +0000
f (strcasecmp(XferEnc, "7bit") == 0) { CurrEncodingIsQP = 0; BodyType = (MSG_IS_7BIT); } else if (strcasecmp(XferEnc, "8bit") == 0) { CurrEncodingIsQP = 0; BodyType = (MSG_IS_8BIT); } } } xfree(XferEnc); xfree(CntType); xfree(MimeVer); return BodyType; } /* * Decode one line of data containing QP data. * Return flag set if this line ends with a soft line-break. * 'bufp' is modified to point to the end of the output buffer. */ static int DoOneQPLine(char **bufp, flag delimited, flag issoftline) { char *buf = *bufp; char *p_in, *p_out, *p; int n; int ret = 0; /* * Special case: line consists of a single =2E and messages are * dot-terminated. Line has to be dot-stuffed after decoding. */ if (delimited && !issoftline && buf[0]=='=' && !strncmp(*bufp, "=2E\r\n", 5)) { strcpy(buf, "..\r\n"); *bufp += 5; return(FALSE); } p_in = buf; if (delimited && issoftline && (strncmp(buf, "..", 2) == 0)) p_in++; for (p_out = buf; (*p_in); ) { p = strchr(p_in, '='); if (p == NULL) { /* No more QP data, just move remainder into place */ n = strlen(p_in); memmove(p_out, p_in, n); p_in += n; p_out += n; } else { if (p > p_in) { /* There are some uncoded chars at the beginning. */ n = (p - p_in); memmove(p_out, p_in, n); p_out += n; } switch (*(p+1)) { case '\0': case '\r': case '\n': /* Soft line break, skip '=' */ p_in = p+1; if (*p_in == '\r') p_in++; if (*p_in == '\n') p_in++; ret = 1; break; default: /* There is a QP encoded byte */ if (qp_char(*(p+1), *(p+2), p_out) == 0) { p_in = p+3; } else { /* Invalid QP data - pass through unchanged. */ *p_out = '='; p_in = p+1; } p_out++; break; } } } *p_out = '\0'; *bufp = p_out; return ret; } /* This is called once per line in the message body. We need to scan * all lines in the message body for the multipart delimiter string, * and handle any body-part headers in such messages (these can toggle * qp-decoding on and off). * * Note: Messages that are NOT multipart-messages go through this * routine quickly, since BodyState will always be S_BODY_DATA, * and MultipartDelimiter is NULL. * * Return flag set if this line ends with a soft line-break. * 'bufp' is modified to point to the end of the output buffer. */ int UnMimeBodyline(char **bufp, flag delimited, flag softline) { char *buf = *bufp; int ret = 0; switch (BodyState) { case S_BODY_HDR: UnMimeHeader(buf); /* Headers in body-parts can be encoded, too! */ if ((*buf == '\0') || (*buf == '\n') || (strcmp(buf, "\r\n") == 0)) { BodyState = S_BODY_DATA; } else if (strncasecmp("Content-Transfer-Encoding:", buf, 26) == 0) { char *XferEnc; XferEnc = nxtaddr(buf); if ((XferEnc != NULL) && (strcasecmp(XferEnc, "quoted-printable") == 0)) { CurrEncodingIsQP = 1; /* * Hmm ... we cannot be really sure that CurrTypeNeedsDecode * has been set - we may not have seen the Content-Type header * yet. But *usually* the Content-Type header comes first, so * this will work. And there is really no way of doing it * "right" as long as we stick with the line-by-line processing. */ if (CurrTypeNeedsDecode) SetEncoding8bit(buf); } } else if (strncasecmp("Content-Type:", buf, 13) == 0) { CurrTypeNeedsDecode = CheckContentType(nxtaddr(buf)); } *bufp = (buf + strlen(buf)); break; case S_BODY_DATA: if ((*MultipartDelimiter) && (strncmp(buf, MultipartDelimiter, strlen(MultipartDelimiter)) == 0)) { BodyState = S_BODY_HDR; CurrEncodingIsQP = CurrTypeNeedsDecode = 0; } if (CurrEncodingIsQP && CurrTypeNeedsDecode) ret = DoOneQPLine(bufp, delimited, softline); else *bufp = (buf + strlen(buf)); break; } return ret; } #ifdef STANDALONE #include #include const char *program_name = "unmime"; int outlevel = 0; #define BUFSIZE_INCREMENT 4096 #ifdef DEBUG #define DBG_FWRITE(B,L,BS,FD) do { if (fwrite((B), (L), (BS), (FD))) { } } while(0) #else #define DBG_FWRITE(B,L,BS,FD) #endif int main(int argc, char *argv[]) { unsigned int BufSize; char *buffer, *buf_p; int nl_count, i, bodytype; /* quench warnings about unused arguments */ (void)argc; (void)argv; #ifdef DEBUG pid_t pid; FILE *fd_orig, *fd_conv; char fnam[100]; /* we don't need snprintf here, but for consistency, we'll use it */ pid = getpid(); snprintf(fnam, sizeof(fnam), "/tmp/i_unmime.%lx", (long)pid); fd_orig = fopen(fnam, "w"); snprintf(fnam, sizeof(fnam), "/tmp/o_unmime.%lx", (long)pid); fd_conv = fopen(fnam, "w"); #endif BufSize = BUFSIZE_INCREMENT; /* Initial size of buffer */ buf_p = buffer = (char *) xmalloc(BufSize); nl_count = 0; do { i = fread(buf_p, 1, 1, stdin); switch (*buf_p) { case '\n': nl_count++; break; case '\r': break; default: nl_count = 0; break; } buf_p++; if ((unsigned)(buf_p - buffer) == BufSize) { /* Buffer is full! Get more room. */ buffer = (char *)xrealloc(buffer, BufSize+BUFSIZE_INCREMENT); buf_p = buffer + BufSize; BufSize += BUFSIZE_INCREMENT; } } while ((i > 0) && (nl_count < 2)); *buf_p = '\0'; DBG_FWRITE(buffer, strlen(buffer), 1, fd_orig); UnMimeHeader(buffer); bodytype = MimeBodyType(buffer, 1); i = strlen(buffer); DBG_FWRITE(buffer, i, 1, fd_conv); if (fwrite(buffer, i, 1, stdout) < 1) { perror("fwrite"); goto barf; } do { buf_p = (buffer - 1); do { buf_p++; i = fread(buf_p, 1, 1, stdin); } while ((i == 1) && (*buf_p != '\n')); if (i == 1) buf_p++; *buf_p = '\0'; DBG_FWRITE(buf, (buf_p - buffer), 1, fd_orig); if (buf_p > buffer) { if (bodytype & MSG_NEEDS_DECODE) { buf_p = buffer; UnMimeBodyline(&buf_p, 0, 0); } DBG_FWRITE(buffer, (buf_p - buffer), 1, fd_conv); if (fwrite(buffer, (buf_p - buffer), 1, stdout) < 1) { perror("fwrite"); goto barf; } } } while (buf_p > buffer); barf: free(buffer); if (EOF == fflush(stdout)) perror("fflush"); #ifdef DEBUG fclose(fd_orig); fclose(fd_conv); #endif return 0; } #endif