Fix invalid pointer arithmetic.

[nmh] / sbr / encode_rfc2047.c

diff --git a/sbr/encode_rfc2047.c b/sbr/encode_rfc2047.c
index 45fa501295bfab4768d623213d9edb5fefb025c9..0ded2e932cfa88fae443df7c9a96c1aa80307a0e 100644 (file)
--- a/sbr/encode_rfc2047.c
+++ b/sbr/encode_rfc2047.c
@@ -1,5 +1,4 @@
-/*
- * Routines to encode message headers using RFC 2047-encoding.
+/* encode_rfc2047.c -- encode message headers using RFC 2047 encoding.

  *
  * This code is Copyright (c) 2002, by the authors of nmh.  See the
  * COPYRIGHT file in the root directory of the nmh distribution for
  *
  * This code is Copyright (c) 2002, by the authors of nmh.  See the
  * COPYRIGHT file in the root directory of the nmh distribution for


@@ -10,6 +9,8 @@
 #include <h/mhparse.h>
 #include <h/addrsbr.h>
 #include <h/utils.h>
 #include <h/mhparse.h>
 #include <h/addrsbr.h>
 #include <h/utils.h>

+#include "base64.h"
+#include "unquote.h"

 
 /*
  * List of headers that contain addresses and as a result require special
 
 /*
  * List of headers that contain addresses and as a result require special


@@ -107,7 +108,7 @@ encode_rfc2047(const char *name, char **value, int encoding,
        charset = write_charset_8bit();
 
     if (strcasecmp(charset, "US-ASCII") == 0) {
        charset = write_charset_8bit();
 
     if (strcasecmp(charset, "US-ASCII") == 0) {

-       advise(NULL, "Cannot use US-ASCII with 8 bit characters in header");
+       inform("Cannot use US-ASCII with 8 bit characters in header");

        return 1;
     }
 
        return 1;
     }
 


@@ -125,14 +126,14 @@ encode_rfc2047(const char *name, char **value, int encoding,
      * On the encoding we choose, and the specifics of encoding:
      *
      * - If a specified encoding is passed in, we use that.
      * On the encoding we choose, and the specifics of encoding:
      *
      * - If a specified encoding is passed in, we use that.

-     * - If more than 50% of the characters are high-bit, we use base64
-     *   and encode the whole field as one atom (possibly split).
-     * - Otherwise, we use quoted-printable.
+     * - Otherwise, pick which encoding is shorter.
+     *
+     * We don't quite handle continuation right here, but it should be
+     * pretty close.

      */
 
     if (encoding == CE_UNKNOWN)
      */
 
     if (encoding == CE_UNKNOWN)

-       encoding = (eightbitcount * 10 / (asciicount + eightbitcount) > 5) ?
-                                               CE_BASE64 : CE_QUOTED;
+        encoding = pref_encoding(asciicount, qpspecialcount, eightbitcount);

 
     unfold_header(value, asciicount + eightbitcount);
 
 
     unfold_header(value, asciicount + eightbitcount);
 


@@ -146,7 +147,7 @@ encode_rfc2047(const char *name, char **value, int encoding,
                                   eightbitcount + qpspecialcount, 0);
 
     default:
                                   eightbitcount + qpspecialcount, 0);
 
     default:

-       advise(NULL, "Internal error: unknown RFC-2047 encoding type");
+       inform("Internal error: unknown RFC-2047 encoding type");

        return 1;
     }
 }
        return 1;
     }
 }


@@ -161,7 +162,7 @@ field_encode_quoted(const char *name, char **value, const char *charset,
 {
     int prefixlen = name ? strlen(name) + 2: 0, outlen = 0, column, newline = 1;
     int charsetlen = strlen(charset), utf8;
 {
     int prefixlen = name ? strlen(name) + 2: 0, outlen = 0, column, newline = 1;
     int charsetlen = strlen(charset), utf8;

-    char *output = NULL, *p, *q;
+    char *output = NULL, *p, *q = NULL;

 
     /*
      * Right now we just encode the whole thing.  Maybe later on we'll
 
     /*
      * Right now we just encode the whole thing.  Maybe later on we'll


@@ -281,15 +282,24 @@ field_encode_quoted(const char *name, char **value, const char *charset,
             * allow for the encoded output.
             */
            if (column + (utf8len(p) * 3) > ENCODELINELIMIT - 2) {
             * allow for the encoded output.
             */
            if (column + (utf8len(p) * 3) > ENCODELINELIMIT - 2) {

-               newline = 1;
+               newline = 1;

            }
        }
     }
 
            }
        }
     }
 

-    strcat(q, "?=");
+    if (q == NULL) {
+       /* This should never happen, but just in case.  Found by
+          clang static analyzer. */
+       inform("null output encoding for %s, continuing...", *value);
+       return 1;
+    }
+    *q++ = '?';
+    *q++ = '=';

 
     if (prefixlen)
 
     if (prefixlen)

-       strcat(q, "\n");
+       *q++ = '\n';
+
+    *q = '\0';

 
     free(*value);
 
 
     free(*value);
 


@@ -310,7 +320,7 @@ field_encode_base64(const char *name, char **value, const char *charset)
 {
     int prefixlen = name ? strlen(name) + 2 : 0, charsetlen = strlen(charset);
     int outlen = 0, numencode, curlen;
 {
     int prefixlen = name ? strlen(name) + 2 : 0, charsetlen = strlen(charset);
     int outlen = 0, numencode, curlen;

-    char *output = NULL, *p = *value, *q = NULL, *linestart;
+    char *output = NULL, *p = *value, *q = NULL, *linestart = NULL;

 
     /*
      * Skip over any leading white space.
 
     /*
      * Skip over any leading white space.


@@ -372,7 +382,7 @@ field_encode_base64(const char *name, char **value, const char *charset)
        numencode = strbase64(ENCODELINELIMIT - (q - linestart) - 2);
 
        if (numencode <= 0) {
        numencode = strbase64(ENCODELINELIMIT - (q - linestart) - 2);
 
        if (numencode <= 0) {

-           advise(NULL, "Internal error: tried to encode %d characters "
+           inform("Internal error: tried to encode %d characters "

                   "in base64", numencode);
            return 1;
        }
                   "in base64", numencode);
            return 1;
        }


@@ -396,7 +406,7 @@ field_encode_base64(const char *name, char **value, const char *charset)
                numencode--;
 
            if (numencode == 0) {
                numencode--;
 
            if (numencode == 0) {

-               advise(NULL, "Internal error: could not find start of "
+               inform("Internal error: could not find start of "

                       "UTF-8 character when base64 encoding header");
                return 1;
            }
                       "UTF-8 character when base64 encoding header");
                return 1;
            }


@@ -404,7 +414,7 @@ field_encode_base64(const char *name, char **value, const char *charset)
 
        if (writeBase64raw((unsigned char *) p, numencode,
                           (unsigned char *) q) != OK) {
 
        if (writeBase64raw((unsigned char *) p, numencode,
                           (unsigned char *) q) != OK) {

-           advise(NULL, "Internal error: base64 encoding of header failed");
+           inform("Internal error: base64 encoding of header failed");

            return 1;
        }
 
            return 1;
        }
 


@@ -451,7 +461,7 @@ field_encode_base64(const char *name, char **value, const char *charset)
 
     if (writeBase64raw((unsigned char *) p, strlen(p),
                       (unsigned char *) q) != OK) {
 
     if (writeBase64raw((unsigned char *) p, strlen(p),
                       (unsigned char *) q) != OK) {

-       advise(NULL, "Internal error: base64 encoding of header failed");
+       inform("Internal error: base64 encoding of header failed");

        return 1;
     }
 
        return 1;
     }
 


@@ -514,8 +524,8 @@ unfold_header(char **value, int len)
             * This has the side effect of stripping off the final newline
             * for the header; we put it back in the encoding routine.
             */
             * This has the side effect of stripping off the final newline
             * for the header; we put it back in the encoding routine.
             */

-           while (is_fws(*q++))
-               ;
+           while (is_fws(*q))
+               q++;

            if (*q == '\0')
                break;
 
            if (*q == '\0')
                break;
 


@@ -542,12 +552,12 @@ field_encode_address(const char *name, char **value, int encoding,
 {
     int prefixlen = strlen(name) + 2, column = prefixlen, groupflag;
     int asciichars, specialchars, eightbitchars, reformat = 0, errflag = 0;
 {
     int prefixlen = strlen(name) + 2, column = prefixlen, groupflag;
     int asciichars, specialchars, eightbitchars, reformat = 0, errflag = 0;

-    int retval;

     size_t len;
     size_t len;

-    char *mp, *output = NULL;
+    char *mp, *cp = NULL, *output = NULL;

     char *tmpbuf = NULL;
     size_t tmpbufsize = 0;
     struct mailname *mn;
     char *tmpbuf = NULL;
     size_t tmpbufsize = 0;
     struct mailname *mn;

+    char errbuf[BUFSIZ];

 
     /*
      * Because these are addresses, we need to handle them individually.
 
     /*
      * Because these are addresses, we need to handle them individually.


@@ -564,11 +574,14 @@ field_encode_address(const char *name, char **value, int encoding,
     output = add(" ", output);
 
     for (groupflag = 0; (mp = getname(*value)); ) {
     output = add(" ", output);
 
     for (groupflag = 0; (mp = getname(*value)); ) {

-       if ((mn = getm(mp, NULL, 0, AD_HOST, NULL)) == NULL) {
+       if ((mn = getm(mp, NULL, 0, errbuf, sizeof(errbuf))) == NULL) {
+           inform("%s: %s", errbuf, mp);

            errflag++;
            continue;
        }
 
            errflag++;
            continue;
        }
 

+       reformat = 0;
+

        /*
         * We only care if the phrase (m_pers) or any trailing comment
         * (m_note) have 8-bit characters.  If doing q-p, we also need
        /*
         * We only care if the phrase (m_pers) or any trailing comment
         * (m_note) have 8-bit characters.  If doing q-p, we also need


@@ -576,6 +589,9 @@ field_encode_address(const char *name, char **value, int encoding,
         * so the specialchars count is right.
         */
 
         * so the specialchars count is right.
         */
 

+       if (! mn->m_pers)
+           goto check_note;
+

        if ((len = strlen(mn->m_pers)) + 1 > tmpbufsize) {
            tmpbuf = mh_xrealloc(tmpbuf, tmpbufsize = len + 1);
        }
        if ((len = strlen(mn->m_pers)) + 1 > tmpbufsize) {
            tmpbuf = mh_xrealloc(tmpbuf, tmpbufsize = len + 1);
        }


@@ -584,16 +600,16 @@ field_encode_address(const char *name, char **value, int encoding,
 
        if (scanstring(tmpbuf, &asciichars, &eightbitchars,
                       &specialchars)) {
 
        if (scanstring(tmpbuf, &asciichars, &eightbitchars,
                       &specialchars)) {

-               /*
-                * If we have 8-bit characters, encode it.
-                */
+           /*
+            * If we have 8-bit characters, encode it.
+            */

 
            if (encoding == CE_UNKNOWN)
                encoding = pref_encoding(asciichars, specialchars,
                                         eightbitchars);
 
            /*
 
            if (encoding == CE_UNKNOWN)
                encoding = pref_encoding(asciichars, specialchars,
                                         eightbitchars);
 
            /*

-            * This is okay, because the output of scanstring will be either
+            * This is okay, because the output of unquote_string will be either

             * equal or shorter than the original.
             */
 
             * equal or shorter than the original.
             */
 


@@ -602,29 +618,189 @@ field_encode_address(const char *name, char **value, int encoding,
            switch (encoding) {
 
            case CE_BASE64:
            switch (encoding) {
 
            case CE_BASE64:

-               retval = field_encode_base64(NULL, &mn->m_pers, charset);
+               if (field_encode_base64(NULL, &mn->m_pers, charset)) {
+                   errflag++;
+                   goto out;
+               }
+               break;
+
+           case CE_QUOTED:
+               if (field_encode_quoted(NULL, &mn->m_pers, charset, asciichars,
+                                       eightbitchars + specialchars, 1)) {
+                   errflag++;
+                   goto out;
+               }
+               break;
+
+           default:
+               inform("Internal error: unknown RFC-2047 encoding type");
+               errflag++;
+               goto out;
+           }
+
+           reformat++;
+       }
+
+       check_note:
+
+       /*
+        * The "note" field is generally a comment at the end of the address,
+        * at least as how it's implemented here.  Notes are always surrounded
+        * by parenthesis (since they're comments).  Strip them out and
+        * then put them back when we format the final field, but they do
+        * not get encoded.
+        */
+
+       if (! mn->m_note)
+           goto do_reformat;
+
+       if ((len = strlen(mn->m_note)) + 1 > tmpbufsize) {
+           tmpbuf = mh_xrealloc(tmpbuf, tmpbufsize = len + 1);
+       }
+
+       if (mn->m_note[0] != '(' || mn->m_note[len - 1] != ')') {
+           inform("Internal error: Invalid note field \"%s\"",
+                  mn->m_note);
+           errflag++;
+           goto out;
+       }
+
+       strncpy(tmpbuf, mn->m_note + 1, len - 1);
+       tmpbuf[len - 2] = '\0';
+
+       if (scanstring(tmpbuf, &asciichars, &eightbitchars,
+                      &specialchars)) {
+           /*
+            * If we have 8-bit characters, encode it.
+            */
+
+           if (encoding == CE_UNKNOWN)
+               encoding = pref_encoding(asciichars, specialchars,
+                                        eightbitchars);
+
+           switch (encoding) {
+
+           case CE_BASE64:
+               if (field_encode_base64(NULL, &tmpbuf, charset)) {
+                   errflag++;
+                   goto out;
+               }

                break;
 
            case CE_QUOTED:
                break;
 
            case CE_QUOTED:

-               retval = field_encode_quoted(NULL, &mn->m_pers, charset,
-                                            asciichars,
-                                            eightbitchars + specialchars, 1);
+               if (field_encode_quoted(NULL, &tmpbuf, charset, asciichars,
+                                       eightbitchars + specialchars, 1)) {
+                   errflag++;
+                   goto out;
+               }

                break;
 
            default:
                break;
 
            default:

-               advise(NULL, "Internal error: unknown RFC-2047 encoding type");
+               inform("Internal error: unknown RFC-2047 encoding type");

                errflag++;
                goto out;
            }
 
            reformat++;
                errflag++;
                goto out;
            }
 
            reformat++;

+
+           /*
+            * Make sure the size of tmpbuf is correct (it always gets
+            * reallocated in the above functions).
+            */
+
+           tmpbufsize = strlen(tmpbuf) + 1;
+
+           /*
+            * Put the note field back surrounded by parenthesis.
+            */
+
+           mn->m_note = mh_xrealloc(mn->m_note, tmpbufsize + 2);
+
+           snprintf(mn->m_note, tmpbufsize + 2, "(%s)", tmpbuf);
+       }
+
+do_reformat:
+
+       /*
+        * So, some explanation is in order.
+        *
+        * We know we need to rewrite at least one address in the header,
+        * otherwise we wouldn't be here.  If we had to reformat this
+        * particular address, then run it through adrformat().  Otherwise
+        * we can use m_text directly.
+        */
+
+       /*
+        * If we were in a group but are no longer, make sure we add a
+        * semicolon (which needs to be FIRST, as it needs to be at the end
+        * of the last address).
+        */
+
+       if (groupflag && ! mn->m_ingrp) {
+           output = add(";", output);
+           column++;
+       }
+
+       groupflag = mn->m_ingrp;
+
+       if (mn->m_gname) {
+           cp = mh_xstrdup(mn->m_gname);
+       }
+
+       if (reformat) {
+           cp = add(adrformat(mn), cp);
+       } else {
+           cp = add(mn->m_text, cp);
+       }
+
+       len = strlen(cp);
+
+       /*
+        * If we're not at the beginning of the line, add a command and
+        * either a space or a newline.
+        */
+
+       if (column != prefixlen) {
+           if (len + column + 2 > OUTPUTLINELEN) {
+
+               if ((size_t) (prefixlen + 3) < tmpbufsize)
+                   tmpbuf = mh_xrealloc(tmpbuf, tmpbufsize = prefixlen + 3);
+
+               snprintf(tmpbuf, tmpbufsize, ",\n%*s", column = prefixlen, "");
+               output = add(tmpbuf, output);
+           } else {
+               output = add(", ", output);
+               column += 2;
+           }

        }
        }

+
+       /*
+        * Finally add the address
+        */
+
+       output = add(cp, output);
+       column += len;
+       free(cp);
+       cp = NULL;

     }
 
     }
 

-out:
+    /*
+     * Just in case we're at the end of a list
+     */
+
+    if (groupflag) {
+       output = add(";", output);
+    }
+
+    output = add("\n", output);

 
 

-    if (tmpbuf)
-       free(tmpbuf);
+    free(*value);
+    *value = output;
+    output = NULL;
+
+out:
+    free(tmpbuf);
+    free(output);

 
     return errflag > 0;
 }
 
     return errflag > 0;
 }


@@ -644,7 +820,12 @@ scanstring(const char *string, int *asciilen, int *eightbitchars,
     for (; *string != '\0'; string++) {
        if ((isascii((unsigned char) *string))) {
            (*asciilen)++;
     for (; *string != '\0'; string++) {
        if ((isascii((unsigned char) *string))) {
            (*asciilen)++;

-           if (!qphrasevalid((unsigned char) *string))
+           /*
+            * So, a space is not a valid phrase character, but we're counting
+            * an exception here, because in q-p a space can be directly
+            * encoded as an underscore.
+            */
+           if (!qphrasevalid((unsigned char) *string) && *string != ' ')

                (*specialchars)++;
        } else {
            (*eightbitchars)++;
                (*specialchars)++;
        } else {
            (*eightbitchars)++;