removed some debugs
[citadel.git] / citadel / internet_addressing.c
index a1b0a37e176c84748abdb35f90d6202a5b2a5720..e67a9dc12c7a482f5e07a5a74d7c3f79a9da2e24 100644 (file)
@@ -1,7 +1,15 @@
-/*
- * This file contains functions which handle the mapping of Internet addresses
- * to users on the Citadel system.
- */
+// This file contains functions which handle the mapping of Internet addresses
+// to users on the Citadel system.
+//
+// Copyright (c) 1987-2022 by the citadel.org team
+//
+// This program is open source software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 3.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
 
 #include "sysdep.h"
 #include <stdlib.h>
 #include <pwd.h>
 #include <errno.h>
 #include <sys/types.h>
-
-#if TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# if HAVE_SYS_TIME_H
-#  include <sys/time.h>
-# else
-#  include <time.h>
-# endif
-#endif
-
+#include <time.h>
 #include <sys/wait.h>
 #include <string.h>
 #include <limits.h>
@@ -45,8 +42,8 @@
 #ifdef HAVE_ICONV
 #include <iconv.h>
 
+// This is the non-define version in case it is needed for debugging
 #if 0
-/* This is the non-define version in case of s.b. needing to debug */
 inline void FindNextEnd (char *bptr, char *end)
 {
        /* Find the next ?Q? */
@@ -72,10 +69,8 @@ inline void FindNextEnd (char *bptr, char *end)
        } \
 }
 
-/*
- * Handle subjects with RFC2047 encoding such as:
- * =?koi8-r?B?78bP0s3Mxc7JxSDXz9rE1dvO2c3JINvB0sHNySDP?=
- */
+// Handle subjects with RFC2047 encoding such as:
+// =?koi8-r?B?78bP0s3Mxc7JxSDXz9rE1dvO2c3JINvB0sHNySDP?=
 void utf8ify_rfc822_string(char *buf) {
        char *start, *end, *next, *nextend, *ptr;
        char newbuf[1024];
@@ -83,27 +78,26 @@ void utf8ify_rfc822_string(char *buf) {
        char encoding[16];
        char istr[1024];
        iconv_t ic = (iconv_t)(-1) ;
-       char *ibuf;                     /**< Buffer of characters to be converted */
-       char *obuf;                     /**< Buffer for converted characters */
-       size_t ibuflen;                 /**< Length of input buffer */
-       size_t obuflen;                 /**< Length of output buffer */
-       char *isav;                     /**< Saved pointer to input buffer */
-       char *osav;                     /**< Saved pointer to output buffer */
+       char *ibuf;                     // Buffer of characters to be converted
+       char *obuf;                     // Buffer for converted characters
+       size_t ibuflen;                 // Length of input buffer
+       size_t obuflen;                 // Length of output buffer
+       char *isav;                     // Saved pointer to input buffer
+       char *osav;                     // Saved pointer to output buffer
        int passes = 0;
        int i, len, delta;
        int illegal_non_rfc2047_encoding = 0;
 
-       /* Sometimes, badly formed messages contain strings which were simply
-        *  written out directly in some foreign character set instead of
-        *  using RFC2047 encoding.  This is illegal but we will attempt to
-        *  handle it anyway by converting from a user-specified default
-        *  charset to UTF-8 if we see any nonprintable characters.
-        */
+       // Sometimes, badly formed messages contain strings which were simply
+       // written out directly in some foreign character set instead of
+       // using RFC2047 encoding.  This is illegal but we will attempt to
+       // handle it anyway by converting from a user-specified default
+       // charset to UTF-8 if we see any nonprintable characters.
        len = strlen(buf);
        for (i=0; i<len; ++i) {
                if ((buf[i] < 32) || (buf[i] > 126)) {
                        illegal_non_rfc2047_encoding = 1;
-                       i = len; ///< take a shortcut, it won't be more than one.
+                       i = len;        // take a shortcut, it won't be more than one.
                }
        }
        if (illegal_non_rfc2047_encoding) {
@@ -128,25 +122,22 @@ void utf8ify_rfc822_string(char *buf) {
                }
        }
 
-       /* pre evaluate the first pair */
+       // pre evaluate the first pair
        nextend = end = NULL;
        len = strlen(buf);
        start = strstr(buf, "=?");
        if (start != NULL) 
                FindNextEnd (start, end);
 
-       while ((start != NULL) && (end != NULL))
-       {
+       while ((start != NULL) && (end != NULL)) {
                next = strstr(end, "=?");
                if (next != NULL)
                        FindNextEnd(next, nextend);
                if (nextend == NULL)
                        next = NULL;
 
-               /* did we find two partitions */
-               if ((next != NULL) && 
-                   ((next - end) > 2))
-               {
+               // did we find two partitions
+               if ((next != NULL) && ((next - end) > 2)) {
                        ptr = end + 2;
                        while ((ptr < next) && 
                               (isspace(*ptr) ||
@@ -154,60 +145,52 @@ void utf8ify_rfc822_string(char *buf) {
                                (*ptr == '\n') || 
                                (*ptr == '\t')))
                                ptr ++;
-                       /* did we find a gab just filled with blanks? */
-                       if (ptr == next)
-                       {
-                               memmove (end + 2,
-                                        next,
-                                        len - (next - start));
+                       // did we find a gab just filled with blanks?
+                       if (ptr == next) {
+                               memmove(end + 2, next, len - (next - start));
 
-                               /* now terminate the gab at the end */
+                               // now terminate the gab at the end
                                delta = (next - end) - 2;
                                len -= delta;
                                buf[len] = '\0';
 
-                               /* move next to its new location. */
+                               // move next to its new location.
                                next -= delta;
                                nextend -= delta;
                        }
                }
-               /* our next-pair is our new first pair now. */
+               // our next-pair is our new first pair now.
                start = next;
                end = nextend;
        }
 
-       /* Now we handle foreign character sets properly encoded
-        * in RFC2047 format.
-        */
+       // Now we handle foreign character sets properly encoded in RFC2047 format.
        start = strstr(buf, "=?");
        FindNextEnd((start != NULL)? start : buf, end);
-       while (start != NULL && end != NULL && end > start)
-       {
+       while (start != NULL && end != NULL && end > start) {
                extract_token(charset, start, 1, '?', sizeof charset);
                extract_token(encoding, start, 2, '?', sizeof encoding);
                extract_token(istr, start, 3, '?', sizeof istr);
 
                ibuf = malloc(1024);
                isav = ibuf;
-               if (!strcasecmp(encoding, "B")) {       /**< base64 */
+               if (!strcasecmp(encoding, "B")) {       // base64
                        ibuflen = CtdlDecodeBase64(ibuf, istr, strlen(istr));
                }
-               else if (!strcasecmp(encoding, "Q")) {  /**< quoted-printable */
+               else if (!strcasecmp(encoding, "Q")) {  // quoted-printable
                        size_t len;
-                       long pos;
+                       unsigned long pos;
                        
                        len = strlen(istr);
                        pos = 0;
-                       while (pos < len)
-                       {
+                       while (pos < len) {
                                if (istr[pos] == '_') istr[pos] = ' ';
                                pos++;
                        }
-
                        ibuflen = CtdlDecodeQuotedPrintable(ibuf, istr, len);
                }
                else {
-                       strcpy(ibuf, istr);             /**< unknown encoding */
+                       strcpy(ibuf, istr);             // unknown encoding
                        ibuflen = strlen(istr);
                }
 
@@ -249,12 +232,10 @@ void utf8ify_rfc822_string(char *buf) {
 
                free(isav);
 
-               /*
-                * Since spammers will go to all sorts of absurd lengths to get their
-                * messages through, there are LOTS of corrupt headers out there.
-                * So, prevent a really badly formed RFC2047 header from throwing
-                * this function into an infinite loop.
-                */
+               // Since spammers will go to all sorts of absurd lengths to get their
+               // messages through, there are LOTS of corrupt headers out there.
+               // So, prevent a really badly formed RFC2047 header from throwing
+               // this function into an infinite loop.
                ++passes;
                if (passes > 20) return;
 
@@ -269,19 +250,9 @@ inline void utf8ify_rfc822_string(char *a){};
 #endif
 
 
-
-struct trynamebuf {
-       char buffer1[SIZ];
-       char buffer2[SIZ];
-};
-
 char *inetcfg = NULL;
-struct spamstrings_t *spamstrings = NULL;
-
 
-/*
- * Return nonzero if the supplied name is an alias for this host.
- */
+// Return nonzero if the supplied name is an alias for this host.
 int CtdlHostAlias(char *fqdn) {
        int config_lines;
        int i;
@@ -289,12 +260,12 @@ int CtdlHostAlias(char *fqdn) {
        char host[256], type[256];
        int found = 0;
 
-       if (fqdn == NULL) return(hostalias_nomatch);
-       if (IsEmptyStr(fqdn)) return(hostalias_nomatch);
-       if (!strcasecmp(fqdn, "localhost")) return(hostalias_localhost);
-       if (!strcasecmp(fqdn, config.c_fqdn)) return(hostalias_localhost);
-       if (!strcasecmp(fqdn, config.c_nodename)) return(hostalias_localhost);
-       if (inetcfg == NULL) return(hostalias_nomatch);
+       if (fqdn == NULL)                                       return(hostalias_nomatch);
+       if (IsEmptyStr(fqdn))                                   return(hostalias_nomatch);
+       if (!strcasecmp(fqdn, "localhost"))                     return(hostalias_localhost);
+       if (!strcasecmp(fqdn, CtdlGetConfigStr("c_fqdn")))      return(hostalias_localhost);
+       if (!strcasecmp(fqdn, CtdlGetConfigStr("c_nodename")))  return(hostalias_localhost);
+       if (inetcfg == NULL)                                    return(hostalias_nomatch);
 
        config_lines = num_tokens(inetcfg, '\n');
        for (i=0; i<config_lines; ++i) {
@@ -304,33 +275,30 @@ int CtdlHostAlias(char *fqdn) {
 
                found = 0;
 
-               /* Process these in a specific order, in case there are multiple matches.
-                * We want directory to override masq, for example.
-                */
+               // Process these in a specific order, in case there are multiple matches.
+               // We want localhost to override masq, for example.
 
                if ( (!strcasecmp(type, "masqdomain")) && (!strcasecmp(fqdn, host))) {
                        found = hostalias_masq;
                }
+
                if ( (!strcasecmp(type, "localhost")) && (!strcasecmp(fqdn, host))) {
                        found = hostalias_localhost;
                }
+
+               // "directory" used to be a distributed version of "localhost" but they're both the same now
                if ( (!strcasecmp(type, "directory")) && (!strcasecmp(fqdn, host))) {
-                       found = hostalias_directory;
+                       found = hostalias_localhost;
                }
 
                if (found) return(found);
        }
-
        return(hostalias_nomatch);
 }
 
 
-
-/*
- * Determine whether a given Internet address belongs to the current user
- */
-int CtdlIsMe(char *addr, int addr_buf_len)
-{
+// Determine whether a given Internet address belongs to the current user
+int CtdlIsMe(char *addr, int addr_buf_len) {
        struct recptypes *recp;
        int i;
 
@@ -355,30 +323,9 @@ int CtdlIsMe(char *addr, int addr_buf_len)
 }
 
 
-/*
- * Citadel protocol command to do the same
- */
-void cmd_isme(char *argbuf) {
-       char addr[256];
-
-       if (CtdlAccessCheck(ac_logged_in)) return;
-       extract_token(addr, argbuf, 0, '|', sizeof addr);
-
-       if (CtdlIsMe(addr, sizeof addr)) {
-               cprintf("%d %s\n", CIT_OK, addr);
-       }
-       else {
-               cprintf("%d Not you.\n", ERROR + ILLEGAL_VALUE);
-       }
-
-}
-
-
-/* If the last item in a list of recipients was truncated to a partial address,
- * remove it completely in order to avoid choking libSieve
- */
-void sanitize_truncated_recipient(char *str)
-{
+// If the last item in a list of recipients was truncated to a partial address,
+// remove it completely in order to avoid choking library functions.
+void sanitize_truncated_recipient(char *str) {
        if (!str) return;
        if (num_tokens(str, ',') < 2) return;
 
@@ -398,186 +345,188 @@ void sanitize_truncated_recipient(char *str)
 }
 
 
+// This function is self explanatory.
+// (What can I say, I'm in a weird mood today...)
+void remove_any_whitespace_to_the_left_or_right_of_at_symbol(char *name) {
+       char *ptr;
+       if (!name) return;
 
-
-
-/*
- * This function is self explanatory.
- * (What can I say, I'm in a weird mood today...)
- */
-void remove_any_whitespace_to_the_left_or_right_of_at_symbol(char *name)
-{
-       int i;
-
-       for (i = 0; i < strlen(name); ++i) {
-               if (name[i] == '@') {
-                       while (isspace(name[i - 1]) && i > 0) {
-                               strcpy(&name[i - 1], &name[i]);
-                               --i;
-                       }
-                       while (isspace(name[i + 1])) {
-                               strcpy(&name[i + 1], &name[i + 2]);
-                       }
+       for (ptr=name; *ptr; ++ptr) {
+               while ( (isspace(*ptr)) && (*(ptr+1)=='@') ) {
+                       strcpy(ptr, ptr+1);
+                       if (ptr > name) --ptr;
+               }
+               while ( (*ptr=='@') && (*(ptr+1)!=0) && (isspace(*(ptr+1))) ) {
+                       strcpy(ptr+1, ptr+2);
                }
        }
 }
 
 
-/*
- * Aliasing for network mail.
- * (Error messages have been commented out, because this is a server.)
- */
-int alias(char *name)
-{                              /* process alias and routing info for mail */
-       struct CitContext *CCC = CC;
-       FILE *fp;
-       int a, i;
-       char aaa[SIZ], bbb[SIZ];
-       char *ignetcfg = NULL;
-       char *ignetmap = NULL;
+// values that can be returned by expand_aliases()
+enum {
+       EA_ERROR,               // Can't send message due to bad address
+       EA_MULTIPLE,            // Alias expanded into multiple recipients -- run me again!
+       EA_LOCAL,               // Local message, do no network processing
+       EA_INTERNET,            // Convert msg and send as Internet mail
+       EA_SKIP                 // This recipient has been invalidated -- skip it!
+};
+
+
+// Process alias and routing info for email addresses
+int expand_aliases(char *name, char *aliases) {
+       int a;
+       char aaa[SIZ];
        int at = 0;
-       char node[64];
-       char testnode[64];
-       char buf[SIZ];
 
-       char original_name[256];
+       if (aliases) {
+               int num_aliases = num_tokens(aliases, '\n');
+               for (a=0; a<num_aliases; ++a) {
+                       extract_token(aaa, aliases, a, '\n', sizeof aaa);
+                       char *bar = strchr(aaa, '|');
+                       if (bar) {
+                               bar[0] = 0;
+                               ++bar;
+                               striplt(aaa);
+                               striplt(bar);
+                               if ( (!IsEmptyStr(aaa)) && (!strcasecmp(name, aaa)) ) {
+                                       syslog(LOG_DEBUG, "internet_addressing: global alias <%s> to <%s>", name, bar);
+                                       strcpy(name, bar);
+                               }
+                       }
+               }
+               if (strchr(name, ',')) {
+                       return(EA_MULTIPLE);
+               }
+       }
+
+       char original_name[256];                                // Now go for the regular aliases
        safestrncpy(original_name, name, sizeof original_name);
 
+       // should these checks still be here, or maybe move them to split_recps() ?
        striplt(name);
        remove_any_whitespace_to_the_left_or_right_of_at_symbol(name);
        stripallbut(name, '<', '>');
 
-       fp = fopen(file_mail_aliases, "r");
-       if (fp == NULL) {
-               fp = fopen("/dev/null", "r");
-       }
-       if (fp == NULL) {
-               return (MES_ERROR);
-       }
-       strcpy(aaa, "");
-       strcpy(bbb, "");
-       while (fgets(aaa, sizeof aaa, fp) != NULL) {
-               while (isspace(name[0]))
-                       strcpy(name, &name[1]);
-               aaa[strlen(aaa) - 1] = 0;
-               strcpy(bbb, "");
-               for (a = 0; a < strlen(aaa); ++a) {
-                       if (aaa[a] == ',') {
-                               strcpy(bbb, &aaa[a + 1]);
-                               aaa[a] = 0;
-                       }
-               }
-               if (!strcasecmp(name, aaa))
-                       strcpy(name, bbb);
-       }
-       fclose(fp);
-
-       /* Hit the Global Address Book */
+       // Hit the email address directory
        if (CtdlDirectoryLookup(aaa, name, sizeof aaa) == 0) {
                strcpy(name, aaa);
        }
 
        if (strcasecmp(original_name, name)) {
-               MSG_syslog(LOG_INFO, "%s is being forwarded to %s\n", original_name, name);
+               syslog(LOG_INFO, "internet_addressing: directory alias <%s> to <%s>", original_name, name);
        }
 
-       /* Change "user @ xxx" to "user" if xxx is an alias for this host */
-       for (a=0; a<strlen(name); ++a) {
+       // Change "user @ xxx" to "user" if xxx is an alias for this host
+       for (a=0; name[a] != '\0'; ++a) {
                if (name[a] == '@') {
                        if (CtdlHostAlias(&name[a+1]) == hostalias_localhost) {
                                name[a] = 0;
-                               MSG_syslog(LOG_INFO, "Changed to <%s>\n", name);
+                               syslog(LOG_DEBUG, "internet_addressing: host is local, recipient is <%s>", name);
+                               break;
                        }
                }
        }
 
-       /* determine local or remote type, see citadel.h */
+       // Is this a local or remote recipient?
        at = haschar(name, '@');
-       if (at == 0) return(MES_LOCAL);         /* no @'s - local address */
-       if (at > 1) return(MES_ERROR);          /* >1 @'s - invalid address */
-       remove_any_whitespace_to_the_left_or_right_of_at_symbol(name);
+       if (at == 0) {
+               return(EA_LOCAL);                       // no @'s = local address
+       }
+       else if (at == 1) {
+               return(EA_INTERNET);                    // one @ = internet address
+       }
+       else {
+               return(EA_ERROR);                       // more than one @ = badly formed address
+       }
+}
 
-       /* figure out the delivery mode */
-       extract_token(node, name, 1, '@', sizeof node);
 
-       /* If there are one or more dots in the nodename, we assume that it
-        * is an FQDN and will attempt SMTP delivery to the Internet.
-        */
-       if (haschar(node, '.') > 0) {
-               return(MES_INTERNET);
+// Return a supplied list of email addresses as an array, removing superfluous information and syntax.
+// If an existing Array is supplied as "append_to" it will do so; otherwise a new Array is allocated.
+Array *split_recps(char *addresses, Array *append_to) {
+
+       if (IsEmptyStr(addresses)) {            // nothing supplied, nothing returned
+               return(NULL);
        }
 
-       /* Otherwise we look in the IGnet maps for a valid Citadel node.
-        * Try directly-connected nodes first...
-        */
-       ignetcfg = CtdlGetSysConfig(IGNETCFG);
-       for (i=0; i<num_tokens(ignetcfg, '\n'); ++i) {
-               extract_token(buf, ignetcfg, i, '\n', sizeof buf);
-               extract_token(testnode, buf, 0, '|', sizeof testnode);
-               if (!strcasecmp(node, testnode)) {
-                       free(ignetcfg);
-                       return(MES_IGNET);
+       // Copy the supplied address list into our own memory space, because we are going to modify it.
+       char *a = strdup(addresses);
+       if (a == NULL) {
+               syslog(LOG_ERR, "internet_addressing: malloc() failed: %m");
+               return(NULL);
+       }
+
+       // Strip out anything in double quotes
+       char *l = NULL;
+       char *r = NULL;
+       do {
+               l = strchr(a, '\"');
+               r = strrchr(a, '\"');
+               if (r > l) {
+                       strcpy(l, r+1);
+               }
+       } while (r > l);
+
+       // Transform all qualifying delimiters to commas
+       char *t;
+       for (t=a; t[0]; ++t) {
+               if ((t[0]==';') || (t[0]=='|')) {
+                       t[0]=',';
                }
        }
-       free(ignetcfg);
 
-       /*
-        * Then try nodes that are two or more hops away.
-        */
-       ignetmap = CtdlGetSysConfig(IGNETMAP);
-       for (i=0; i<num_tokens(ignetmap, '\n'); ++i) {
-               extract_token(buf, ignetmap, i, '\n', sizeof buf);
-               extract_token(testnode, buf, 0, '|', sizeof testnode);
-               if (!strcasecmp(node, testnode)) {
-                       free(ignetmap);
-                       return(MES_IGNET);
+       // Tokenize the recipients into an array.  No single recipient should be larger than 256 bytes.
+       Array *recipients_array = NULL;
+       if (append_to) {
+               recipients_array = append_to;                   // Append to an existing array of recipients
+       }
+       else {
+               recipients_array = array_new(256);              // This is a new array of recipients
+       }
+
+       int num_addresses = num_tokens(a, ',');
+       int i;
+       for (i=0; i<num_addresses; ++i) {
+               char this_address[256];
+               extract_token(this_address, a, i, ',', sizeof this_address);
+               striplt(this_address);                          // strip leading and trailing whitespace
+               stripout(this_address, '(', ')');               // remove any portion in parentheses
+               stripallbut(this_address, '<', '>');            // if angle brackets are present, keep only what is inside them
+               if (!IsEmptyStr(this_address)) {
+                       array_append(recipients_array, this_address);
                }
        }
-       free(ignetmap);
 
-       /* If we get to this point it's an invalid node name */
-       return (MES_ERROR);
+       free(a);                                                // We don't need this buffer anymore.
+       return(recipients_array);                               // Return the completed array to the caller.
 }
 
 
-
-/*
- * Validate recipients, count delivery types and errors, and handle aliasing
- * FIXME check for dupes!!!!!
- *
- * Returns 0 if all addresses are ok, ret->num_error = -1 if no addresses 
- * were specified, or the number of addresses found invalid.
- *
- * Caller needs to free the result using free_recipients()
- */
-struct recptypes *validate_recipients(const char *supplied_recipients, 
-                                     const char *RemoteIdentifier, 
-                                     int Flags) {
-       struct CitContext *CCC = CC;
+// Validate recipients, count delivery types and errors, and handle aliasing
+//
+// Returns 0 if all addresses are ok, ret->num_error = -1 if no addresses 
+// were specified, or the number of addresses found invalid.
+//
+// Caller needs to free the result using free_recipients()
+//
+struct recptypes *validate_recipients(char *supplied_recipients, const char *RemoteIdentifier, int Flags) {
        struct recptypes *ret;
        char *recipients = NULL;
-       char *org_recp;
-       char this_recp[256];
-       char this_recp_cooked[256];
        char append[SIZ];
        long len;
-       int num_recps = 0;
-       int i, j;
        int mailtype;
        int invalid;
        struct ctdluser tempUS;
-       struct ctdlroom tempQR;
-       struct ctdlroom tempQR2;
+       struct ctdlroom original_room;
        int err = 0;
        char errmsg[SIZ];
-       int in_quotes = 0;
+       char *org_recp;
+       char this_recp[256];
 
-       /* Initialize */
-       ret = (struct recptypes *) malloc(sizeof(struct recptypes));
+       ret = (struct recptypes *) malloc(sizeof(struct recptypes));                    // Initialize
        if (ret == NULL) return(NULL);
-
-       /* Set all strings to null and numeric values to zero */
-       memset(ret, 0, sizeof(struct recptypes));
+       memset(ret, 0, sizeof(struct recptypes));                                       // set all values to null/zero
 
        if (supplied_recipients == NULL) {
                recipients = strdup("");
@@ -586,125 +535,114 @@ struct recptypes *validate_recipients(const char *supplied_recipients,
                recipients = strdup(supplied_recipients);
        }
 
-       /* Allocate some memory.  Yes, this allocates 500% more memory than we will
-        * actually need, but it's healthier for the heap than doing lots of tiny
-        * realloc() calls instead.
-        */
-       len = strlen(recipients) + 1024;
+       len = strlen(recipients) + 1024;                                                // allocate memory
        ret->errormsg = malloc(len);
        ret->recp_local = malloc(len);
        ret->recp_internet = malloc(len);
-       ret->recp_ignet = malloc(len);
        ret->recp_room = malloc(len);
        ret->display_recp = malloc(len);
        ret->recp_orgroom = malloc(len);
-       org_recp = malloc(len);
 
        ret->errormsg[0] = 0;
        ret->recp_local[0] = 0;
        ret->recp_internet[0] = 0;
-       ret->recp_ignet[0] = 0;
        ret->recp_room[0] = 0;
        ret->recp_orgroom[0] = 0;
        ret->display_recp[0] = 0;
-
        ret->recptypes_magic = RECPTYPES_MAGIC;
 
-       /* Change all valid separator characters to commas */
-       for (i=0; !IsEmptyStr(&recipients[i]); ++i) {
-               if ((recipients[i] == ';') || (recipients[i] == '|')) {
-                       recipients[i] = ',';
-               }
-       }
+       Array *recp_array = split_recps(supplied_recipients, NULL);
 
-       /* Now start extracting recipients... */
+       char *aliases = CtdlGetSysConfig(GLOBAL_ALIASES);                               // First hit the Global Alias Table
 
-       while (!IsEmptyStr(recipients)) {
-               for (i=0; i<=strlen(recipients); ++i) {
-                       if (recipients[i] == '\"') in_quotes = 1 - in_quotes;
-                       if ( ( (recipients[i] == ',') && (!in_quotes) ) || (recipients[i] == 0) ) {
-                               safestrncpy(this_recp, recipients, i+1);
-                               this_recp[i] = 0;
-                               if (recipients[i] == ',') {
-                                       strcpy(recipients, &recipients[i+1]);
-                               }
-                               else {
-                                       strcpy(recipients, "");
-                               }
-                               break;
+       int r;
+       for (r=0; (recp_array && r<array_len(recp_array)); ++r) {
+               org_recp = (char *)array_get_element_at(recp_array, r);
+               strncpy(this_recp, org_recp, sizeof this_recp);
+
+               int i;
+               for (i=0; i<3; ++i) {                                           // pass three times through the aliaser
+                       mailtype = expand_aliases(this_recp, aliases);
+       
+                       // If an alias expanded to multiple recipients, strip off those recipients and append them
+                       // to the end of the array.  This loop will hit those again when it gets there.
+                       if (mailtype == EA_MULTIPLE) {
+                               recp_array = split_recps(this_recp, recp_array);
                        }
                }
 
-               striplt(this_recp);
-               if (IsEmptyStr(this_recp))
-                       break;
-               MSG_syslog(LOG_DEBUG, "Evaluating recipient #%d: %s\n", num_recps, this_recp);
-               ++num_recps;
-
-               strcpy(org_recp, this_recp);
-               alias(this_recp);
-               alias(this_recp);
-               mailtype = alias(this_recp);
-
-               for (j = 0; !IsEmptyStr(&this_recp[j]); ++j) {
-                       if (this_recp[j]=='_') {
-                               this_recp_cooked[j] = ' ';
-                       }
-                       else {
-                               this_recp_cooked[j] = this_recp[j];
+               // This loop searches for duplicate recipients in the final list and marks them to be skipped.
+               int j;
+               for (j=0; j<r; ++j) {
+                       if (!strcasecmp(this_recp, (char *)array_get_element_at(recp_array, j) )) {
+                               mailtype = EA_SKIP;
                        }
                }
-               this_recp_cooked[j] = '\0';
+
+               syslog(LOG_DEBUG, "Recipient #%d of type %d is <%s>", r, mailtype, this_recp);
                invalid = 0;
                errmsg[0] = 0;
                switch(mailtype) {
-               case MES_LOCAL:
+               case EA_LOCAL:                                  // There are several types of "local" recipients.
+
+                       // Old BBS conventions require mail to "sysop" to go somewhere.  Send it to the admin room.
                        if (!strcasecmp(this_recp, "sysop")) {
                                ++ret->num_room;
-                               strcpy(this_recp, config.c_aideroom);
+                               strcpy(this_recp, CtdlGetConfigStr("c_aideroom"));
                                if (!IsEmptyStr(ret->recp_room)) {
                                        strcat(ret->recp_room, "|");
                                }
                                strcat(ret->recp_room, this_recp);
                        }
-                       else if ( (!strncasecmp(this_recp, "room_", 5))
-                                 && (!CtdlGetRoom(&tempQR, &this_recp_cooked[5])) ) {
 
-                               /* Save room so we can restore it later */
-                               tempQR2 = CCC->room;
-                               CCC->room = tempQR;
-                                       
-                               /* Check permissions to send mail to this room */
-                               err = CtdlDoIHavePermissionToPostInThisRoom(
-                                       errmsg, 
-                                       sizeof errmsg, 
-                                       RemoteIdentifier,
-                                       Flags,
-                                       0                       /* 0 = not a reply */
+                       // This handles rooms which can receive posts via email.
+                       else if (!strncasecmp(this_recp, "room_", 5)) {
+                               original_room = CC->room;                               // Remember where we parked
+
+                               char mail_to_room[ROOMNAMELEN];
+                               char *m;
+                               strncpy(mail_to_room, &this_recp[5], sizeof mail_to_room);
+                               for (m = mail_to_room; *m; ++m) {
+                                       if (m[0] == '_') m[0]=' ';
+                               }
+                               if (!CtdlGetRoom(&CC->room, mail_to_room)) {            // Find the room they asked for
+
+                                       err = CtdlDoIHavePermissionToPostInThisRoom(    // check for write permissions to room
+                                               errmsg, 
+                                               sizeof errmsg, 
+                                               RemoteIdentifier,
+                                               Flags,
+                                               0                                       // 0 means "this is not a reply"
                                        );
-                               if (err)
-                               {
+                                       if (err) {
+                                               ++ret->num_error;
+                                               invalid = 1;
+                                       } 
+                                       else {
+                                               ++ret->num_room;
+                                               if (!IsEmptyStr(ret->recp_room)) {
+                                                       strcat(ret->recp_room, "|");
+                                               }
+                                               strcat(ret->recp_room, CC->room.QRname);
+       
+                                               if (!IsEmptyStr(ret->recp_orgroom)) {
+                                                       strcat(ret->recp_orgroom, "|");
+                                               }
+                                               strcat(ret->recp_orgroom, this_recp);
+       
+                                       }
+                               }
+                               else {                                                  // no such room exists
                                        ++ret->num_error;
                                        invalid = 1;
-                               } 
-                               else {
-                                       ++ret->num_room;
-                                       if (!IsEmptyStr(ret->recp_room)) {
-                                               strcat(ret->recp_room, "|");
-                                       }
-                                       strcat(ret->recp_room, &this_recp_cooked[5]);
-
-                                       if (!IsEmptyStr(ret->recp_orgroom)) {
-                                               strcat(ret->recp_orgroom, "|");
-                                       }
-                                       strcat(ret->recp_orgroom, org_recp);
-
                                }
-                                       
-                               /* Restore room in case something needs it */
-                               CCC->room = tempQR2;
+                                               
+                               // Restore this session's original room location.
+                               CC->room = original_room;
 
                        }
+
+                       // This handles the most common case, which is mail to a user's inbox.
                        else if (CtdlGetUser(&tempUS, this_recp) == 0) {
                                ++ret->num_local;
                                strcpy(this_recp, tempUS.fullname);
@@ -713,26 +651,17 @@ struct recptypes *validate_recipients(const char *supplied_recipients,
                                }
                                strcat(ret->recp_local, this_recp);
                        }
-                       else if (CtdlGetUser(&tempUS, this_recp_cooked) == 0) {
-                               ++ret->num_local;
-                               strcpy(this_recp, tempUS.fullname);
-                               if (!IsEmptyStr(ret->recp_local)) {
-                                       strcat(ret->recp_local, "|");
-                               }
-                               strcat(ret->recp_local, this_recp);
-                       }
+
+                       // No match for this recipient
                        else {
                                ++ret->num_error;
                                invalid = 1;
                        }
                        break;
-               case MES_INTERNET:
-                       /* Yes, you're reading this correctly: if the target
-                        * domain points back to the local system or an attached
-                        * Citadel directory, the address is invalid.  That's
-                        * because if the address were valid, we would have
-                        * already translated it to a local address by now.
-                        */
+               case EA_INTERNET:
+                       // Yes, you're reading this correctly: if the target domain points back to the local system,
+                       // the address is invalid.  That's because if the address were valid, we would have
+                       // already translated it to a local address by now.
                        if (IsDirectory(this_recp, 0)) {
                                ++ret->num_error;
                                invalid = 1;
@@ -745,14 +674,11 @@ struct recptypes *validate_recipients(const char *supplied_recipients,
                                strcat(ret->recp_internet, this_recp);
                        }
                        break;
-               case MES_IGNET:
-                       ++ret->num_ignet;
-                       if (!IsEmptyStr(ret->recp_ignet)) {
-                               strcat(ret->recp_ignet, "|");
-                       }
-                       strcat(ret->recp_ignet, this_recp);
+               case EA_MULTIPLE:
+               case EA_SKIP:
+                       // no action required, anything in this slot has already been processed elsewhere
                        break;
-               case MES_ERROR:
+               case EA_ERROR:
                        ++ret->num_error;
                        invalid = 1;
                        break;
@@ -783,29 +709,30 @@ struct recptypes *validate_recipients(const char *supplied_recipients,
                        }
                }
        }
-       free(org_recp);
 
-       if ((ret->num_local + ret->num_internet + ret->num_ignet +
-            ret->num_room + ret->num_error) == 0) {
+       if (aliases != NULL) {          // ok, we're done with the global alias list now
+               free(aliases);
+       }
+
+       if ( (ret->num_local + ret->num_internet + ret->num_room + ret->num_error) == 0) {
                ret->num_error = (-1);
                strcpy(ret->errormsg, "No recipients specified.");
        }
 
-       MSGM_syslog(LOG_DEBUG, "validate_recipients()\n");
-       MSG_syslog(LOG_DEBUG, " local: %d <%s>\n", ret->num_local, ret->recp_local);
-       MSG_syslog(LOG_DEBUG, "  room: %d <%s>\n", ret->num_room, ret->recp_room);
-       MSG_syslog(LOG_DEBUG, "  inet: %d <%s>\n", ret->num_internet, ret->recp_internet);
-       MSG_syslog(LOG_DEBUG, " ignet: %d <%s>\n", ret->num_ignet, ret->recp_ignet);
-       MSG_syslog(LOG_DEBUG, " error: %d <%s>\n", ret->num_error, ret->errormsg);
+       syslog(LOG_DEBUG, "internet_addressing: validate_recipients() = %d local, %d room, %d SMTP, %d error",
+               ret->num_local, ret->num_room, ret->num_internet, ret->num_error
+       );
 
        free(recipients);
+       if (recp_array) {
+               array_free(recp_array);
+       }
+
        return(ret);
 }
 
 
-/*
- * Destructor for struct recptypes
- */
+// Destructor for recptypes
 void free_recipients(struct recptypes *valid) {
 
        if (valid == NULL) {
@@ -813,15 +740,13 @@ void free_recipients(struct recptypes *valid) {
        }
 
        if (valid->recptypes_magic != RECPTYPES_MAGIC) {
-               struct CitContext *CCC = CC;
-               MSGM_syslog(LOG_EMERG, "Attempt to call free_recipients() on some other data type!\n");
+               syslog(LOG_ERR, "internet_addressing: attempt to call free_recipients() on some other data type!");
                abort();
        }
 
        if (valid->errormsg != NULL)            free(valid->errormsg);
        if (valid->recp_local != NULL)          free(valid->recp_local);
        if (valid->recp_internet != NULL)       free(valid->recp_internet);
-       if (valid->recp_ignet != NULL)          free(valid->recp_ignet);
        if (valid->recp_room != NULL)           free(valid->recp_room);
        if (valid->recp_orgroom != NULL)        free(valid->recp_orgroom);
        if (valid->display_recp != NULL)        free(valid->display_recp);
@@ -832,9 +757,7 @@ void free_recipients(struct recptypes *valid) {
 }
 
 
-char *qp_encode_email_addrs(char *source)
-{
-       struct CitContext *CCC = CC;
+char *qp_encode_email_addrs(char *source) {
        char *user, *node, *name;
        const char headerStr[] = "=?UTF-8?Q?";
        char *Encoded;
@@ -853,8 +776,7 @@ char *qp_encode_email_addrs(char *source)
 
        if (source == NULL) return source;
        if (IsEmptyStr(source)) return source;
-       if (MessageDebugEnabled != 0) cit_backtrace();
-       MSG_syslog(LOG_DEBUG, "qp_encode_email_addrs: [%s]\n", source);
+       syslog(LOG_DEBUG, "internet_addressing: qp_encode_email_addrs <%s>", source);
 
        AddrPtr = malloc (sizeof (long) * nAddrPtrMax);
        AddrUtf8 = malloc (sizeof (long) * nAddrPtrMax);
@@ -870,20 +792,19 @@ char *qp_encode_email_addrs(char *source)
                        free (AddrPtr), AddrPtr = ptr;
 
                        ptr = (long *) malloc(sizeof (long) * nAddrPtrMax * 2);
-                       memset(&ptr[nAddrPtrMax], 0, 
-                              sizeof (long) * nAddrPtrMax);
+                       memset(&ptr[nAddrPtrMax], 0, sizeof (long) * nAddrPtrMax);
 
                        memcpy (ptr, AddrUtf8, sizeof (long) * nAddrPtrMax);
                        free (AddrUtf8), AddrUtf8 = ptr;
                        nAddrPtrMax *= 2;                               
                }
-               if (((unsigned char) source[i] < 32) || 
-                   ((unsigned char) source[i] > 126)) {
+               if (((unsigned char) source[i] < 32) || ((unsigned char) source[i] > 126)) {
                        need_to_encode = 1;
                        AddrUtf8[nColons] = 1;
                }
-               if (source[i] == '"')
+               if (source[i] == '"') {
                        InQuotes = !InQuotes;
+               }
                if (!InQuotes && source[i] == ',') {
                        AddrPtr[nColons] = i;
                        nColons++;
@@ -900,9 +821,10 @@ char *qp_encode_email_addrs(char *source)
        EncodedMaxLen = nColons * (sizeof(headerStr) + 3) + SourceLen * 3;
        Encoded = (char*) malloc (EncodedMaxLen);
 
-       for (i = 0; i < nColons; i++)
+       for (i = 0; i < nColons; i++) {
                source[AddrPtr[i]++] = '\0';
-       /* TODO: if libidn, this might get larger*/
+       }
+       // TODO: if libidn, this might get larger
        user = malloc(SourceLen + 1);
        node = malloc(SourceLen + 1);
        name = malloc(SourceLen + 1);
@@ -912,28 +834,19 @@ char *qp_encode_email_addrs(char *source)
        for (i = 0; i < nColons && nPtr != NULL; i++) {
                nmax = EncodedMaxLen - (nPtr - Encoded);
                if (AddrUtf8[i]) {
-                       process_rfc822_addr(&source[AddrPtr[i]], 
-                                           user,
-                                           node,
-                                           name);
-                       /* TODO: libIDN here ! */
+                       process_rfc822_addr(&source[AddrPtr[i]], user, node, name);
+                       // TODO: libIDN here !
                        if (IsEmptyStr(name)) {
-                               n = snprintf(nPtr, nmax, 
-                                            (i==0)?"%s@%s" : ",%s@%s",
-                                            user, node);
+                               n = snprintf(nPtr, nmax, (i==0)?"%s@%s" : ",%s@%s", user, node);
                        }
                        else {
                                EncodedName = rfc2047encode(name, strlen(name));                        
-                               n = snprintf(nPtr, nmax, 
-                                            (i==0)?"%s <%s@%s>" : ",%s <%s@%s>",
-                                            EncodedName, user, node);
+                               n = snprintf(nPtr, nmax, (i==0)?"%s <%s@%s>" : ",%s <%s@%s>", EncodedName, user, node);
                                free(EncodedName);
                        }
                }
                else { 
-                       n = snprintf(nPtr, nmax, 
-                                    (i==0)?"%s" : ",%s",
-                                    &source[AddrPtr[i]]);
+                       n = snprintf(nPtr, nmax, (i==0)?"%s" : ",%s", &source[AddrPtr[i]]);
                }
                if (n > 0 )
                        nPtr += n;
@@ -944,7 +857,7 @@ char *qp_encode_email_addrs(char *source)
                        nnPtr = ptr + (nPtr - Encoded), nPtr = nnPtr;
                        free(Encoded), Encoded = ptr;
                        EncodedMaxLen *= 2;
-                       i--; /* do it once more with properly lengthened buffer */
+                       i--; // do it once more with properly lengthened buffer
                }
        }
        for (i = 0; i < nColons; i++)
@@ -959,34 +872,7 @@ char *qp_encode_email_addrs(char *source)
 }
 
 
-/*
- * Return 0 if a given string fuzzy-matches a Citadel user account
- *
- * FIXME ... this needs to be updated to handle aliases.
- */
-int fuzzy_match(struct ctdluser *us, char *matchstring) {
-       int a;
-       long len;
-
-       if ( (!strncasecmp(matchstring, "cit", 3)) 
-          && (atol(&matchstring[3]) == us->usernum)) {
-               return 0;
-       }
-
-       len = strlen(matchstring);
-       for (a=0; !IsEmptyStr(&us->fullname[a]); ++a) {
-               if (!strncasecmp(&us->fullname[a],
-                  matchstring, len)) {
-                       return 0;
-               }
-       }
-       return -1;
-}
-
-
-/*
- * Unfold a multi-line field into a single line, removing multi-whitespaces
- */
+// Unfold a multi-line field into a single line, removing multi-whitespaces
 void unfold_rfc822_field(char **field, char **FieldEnd) 
 {
        int quote = 0;
@@ -996,29 +882,31 @@ void unfold_rfc822_field(char **field, char **FieldEnd)
 
        while (isspace(*pField))
                pField++;
-       /* remove leading/trailing whitespace */
+       // remove leading/trailing whitespace
        ;
 
        while (isspace(*pFieldEnd))
                pFieldEnd --;
 
        *FieldEnd = pFieldEnd;
-       /* convert non-space whitespace to spaces, and remove double blanks */
+       // convert non-space whitespace to spaces, and remove double blanks
        for (sField = *field = pField; 
             sField < pFieldEnd; 
             pField++, sField++)
        {
-               if ((*sField=='\r') || (*sField=='\n')) {
-                   sField++;
-                   if  (*sField == '\n')
-                       sField++;
-                   *pField = *sField;
+               if ((*sField=='\r') || (*sField=='\n'))
+               {
+                       int offset = 1;
+                       while ( ( (*(sField + offset) == '\r') || (*(sField + offset) == '\n' )) && (sField + offset < pFieldEnd) ) {
+                               offset ++;
+                       }
+                       sField += offset;
+                       *pField = *sField;
                }
                else {
                        if (*sField=='\"') quote = 1 - quote;
                        if (!quote) {
-                               if (isspace(*sField))
-                               {
+                               if (isspace(*sField)) {
                                        *pField = ' ';
                                        pField++;
                                        sField++;
@@ -1038,143 +926,148 @@ void unfold_rfc822_field(char **field, char **FieldEnd)
 }
 
 
-
-/*
- * Split an RFC822-style address into userid, host, and full name
- *
- */
-void process_rfc822_addr(const char *rfc822, char *user, char *node, char *name)
-{
+// Split an RFC822-style address into userid, host, and full name
+//
+// Note: This still handles obsolete address syntaxes such as user%node@node and ...node!user
+//       We should probably remove that.
+void process_rfc822_addr(const char *rfc822, char *user, char *node, char *name) {
        int a;
 
        strcpy(user, "");
-       strcpy(node, config.c_fqdn);
+       strcpy(node, CtdlGetConfigStr("c_fqdn"));
        strcpy(name, "");
 
        if (rfc822 == NULL) return;
 
-       /* extract full name - first, it's From minus <userid> */
+       // extract full name - first, it's From minus <userid>
        strcpy(name, rfc822);
        stripout(name, '<', '>');
 
-       /* strip anything to the left of a bang */
+       // strip anything to the left of a bang
        while ((!IsEmptyStr(name)) && (haschar(name, '!') > 0))
                strcpy(name, &name[1]);
 
-       /* and anything to the right of a @ or % */
-       for (a = 0; a < strlen(name); ++a) {
-               if (name[a] == '@')
+       // and anything to the right of a @ or %
+       for (a = 0; name[a] != '\0'; ++a) {
+               if (name[a] == '@') {
                        name[a] = 0;
-               if (name[a] == '%')
+                       break;
+               }
+               if (name[a] == '%') {
                        name[a] = 0;
+                       break;
+               }
        }
 
-       /* but if there are parentheses, that changes the rules... */
+       // but if there are parentheses, that changes the rules...
        if ((haschar(rfc822, '(') == 1) && (haschar(rfc822, ')') == 1)) {
                strcpy(name, rfc822);
                stripallbut(name, '(', ')');
        }
 
-       /* but if there are a set of quotes, that supersedes everything */
+       // but if there are a set of quotes, that supersedes everything
        if (haschar(rfc822, 34) == 2) {
                strcpy(name, rfc822);
                while ((!IsEmptyStr(name)) && (name[0] != 34)) {
                        strcpy(&name[0], &name[1]);
                }
                strcpy(&name[0], &name[1]);
-               for (a = 0; a < strlen(name); ++a)
-                       if (name[a] == 34)
+               for (a = 0; name[a] != '\0'; ++a)
+                       if (name[a] == 34) {
                                name[a] = 0;
+                               break;
+                       }
        }
-       /* extract user id */
+       // extract user id
        strcpy(user, rfc822);
 
-       /* first get rid of anything in parens */
+       // first get rid of anything in parens
        stripout(user, '(', ')');
 
-       /* if there's a set of angle brackets, strip it down to that */
+       // if there's a set of angle brackets, strip it down to that
        if ((haschar(user, '<') == 1) && (haschar(user, '>') == 1)) {
                stripallbut(user, '<', '>');
        }
 
-       /* strip anything to the left of a bang */
+       // strip anything to the left of a bang
        while ((!IsEmptyStr(user)) && (haschar(user, '!') > 0))
                strcpy(user, &user[1]);
 
-       /* and anything to the right of a @ or % */
-       for (a = 0; a < strlen(user); ++a) {
-               if (user[a] == '@')
+       // and anything to the right of a @ or %
+       for (a = 0; user[a] != '\0'; ++a) {
+               if (user[a] == '@') {
                        user[a] = 0;
-               if (user[a] == '%')
+                       break;
+               }
+               if (user[a] == '%') {
                        user[a] = 0;
+                       break;
+               }
        }
 
 
-       /* extract node name */
+       // extract node name
        strcpy(node, rfc822);
 
-       /* first get rid of anything in parens */
+       // first get rid of anything in parens
        stripout(node, '(', ')');
 
-       /* if there's a set of angle brackets, strip it down to that */
+       // if there's a set of angle brackets, strip it down to that
        if ((haschar(node, '<') == 1) && (haschar(node, '>') == 1)) {
                stripallbut(node, '<', '>');
        }
 
-       /* If no node specified, tack ours on instead */
+       // If no node specified, tack ours on instead
        if (
                (haschar(node, '@')==0)
                && (haschar(node, '%')==0)
                && (haschar(node, '!')==0)
        ) {
-               strcpy(node, config.c_nodename);
+               strcpy(node, CtdlGetConfigStr("c_nodename"));
        }
-
        else {
 
-               /* strip anything to the left of a @ */
+               // strip anything to the left of a @
                while ((!IsEmptyStr(node)) && (haschar(node, '@') > 0))
                        strcpy(node, &node[1]);
        
-               /* strip anything to the left of a % */
+               // strip anything to the left of a %
                while ((!IsEmptyStr(node)) && (haschar(node, '%') > 0))
                        strcpy(node, &node[1]);
        
-               /* reduce multiple system bang paths to node!user */
+               // reduce multiple system bang paths to node!user
                while ((!IsEmptyStr(node)) && (haschar(node, '!') > 1))
                        strcpy(node, &node[1]);
        
-               /* now get rid of the user portion of a node!user string */
-               for (a = 0; a < strlen(node); ++a)
-                       if (node[a] == '!')
+               // now get rid of the user portion of a node!user string
+               for (a = 0; node[a] != '\0'; ++a)
+                       if (node[a] == '!') {
                                node[a] = 0;
+                               break;
+                       }
        }
 
-       /* strip leading and trailing spaces in all strings */
+       // strip leading and trailing spaces in all strings
        striplt(user);
        striplt(node);
        striplt(name);
 
-       /* If we processed a string that had the address in angle brackets
-        * but no name outside the brackets, we now have an empty name.  In
-        * this case, use the user portion of the address as the name.
-        */
+       // If we processed a string that had the address in angle brackets
+       // but no name outside the brackets, we now have an empty name.  In
+       // this case, use the user portion of the address as the name.
        if ((IsEmptyStr(name)) && (!IsEmptyStr(user))) {
                strcpy(name, user);
        }
 }
 
 
-
-/*
- * convert_field() is a helper function for convert_internet_message().
- * Given start/end positions for an rfc822 field, it converts it to a Citadel
- * field if it wants to, and unfolds it if necessary.
- *
- * Returns 1 if the field was converted and inserted into the Citadel message
- * structure, implying that the source field should be removed from the
- * message text.
- */
+// convert_field() is a helper function for convert_internet_message().
+// Given start/end positions for an rfc822 field, it converts it to a Citadel
+// field if it wants to, and unfolds it if necessary.
+//
+// Returns 1 if the field was converted and inserted into the Citadel message
+// structure, implying that the source field should be removed from the
+// message text.
 int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
        char *key, *value, *valueend;
        long len;
@@ -1202,18 +1095,15 @@ int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
        valueend = key + len;
        * ( key + (colonpos - beg) ) = '\0';
        value = &key[(colonpos - beg) + 1];
-/*     printf("Header: [%s]\nValue: [%s]\n", key, value); */
+       // printf("Header: [%s]\nValue: [%s]\n", key, value);
        unfold_rfc822_field(&value, &valueend);
        valuelen = valueend - value + 1;
-/*     printf("UnfoldedValue: [%s]\n", value); */
+       // printf("UnfoldedValue: [%s]\n", value);
 
-       /*
-        * Here's the big rfc822-to-citadel loop.
-        */
+       // Here's the big rfc822-to-citadel loop.
 
-       /* Date/time is converted into a unix timestamp.  If the conversion
-        * fails, we replace it with the time the message arrived locally.
-        */
+       // Date/time is converted into a unix timestamp.  If the conversion
+       // fails, we replace it with the time the message arrived locally.
        if (!strcasecmp(key, "Date")) {
                parsed_date = parsedate(value);
                if (parsed_date < 0L) parsed_date = time(NULL);
@@ -1225,12 +1115,14 @@ int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
 
        else if (!strcasecmp(key, "From")) {
                process_rfc822_addr(value, user, node, name);
-               syslog(LOG_DEBUG, "Converted to <%s@%s> (%s)\n", user, node, name);
+               syslog(LOG_DEBUG, "internet_addressing: converted to <%s@%s> (%s)", user, node, name);
                snprintf(addr, sizeof(addr), "%s@%s", user, node);
-               if (CM_IsEmpty(msg, eAuthor))
-                       CM_SetField(msg, eAuthor, name, strlen(name));
-               if (CM_IsEmpty(msg, erFc822Addr))
-                       CM_SetField(msg, erFc822Addr, addr, strlen(addr));
+               if (CM_IsEmpty(msg, eAuthor) && !IsEmptyStr(name)) {
+                       CM_SetField(msg, eAuthor, name, -1);
+               }
+               if (CM_IsEmpty(msg, erFc822Addr) && !IsEmptyStr(addr)) {
+                       CM_SetField(msg, erFc822Addr, addr, -1);
+               }
                processed = 1;
        }
 
@@ -1260,7 +1152,7 @@ int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
 
        else if (!strcasecmp(key, "Message-ID")) {
                if (!CM_IsEmpty(msg, emessageId)) {
-                       syslog(LOG_WARNING, "duplicate message id\n");
+                       syslog(LOG_WARNING, "internet_addressing: duplicate message id");
                }
                else {
                        char *pValue;
@@ -1268,7 +1160,7 @@ int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
 
                        pValue = value;
                        pValueLen = valuelen;
-                       /* Strip angle brackets */
+                       // Strip angle brackets
                        while (haschar(pValue, '<') > 0) {
                                pValue ++;
                                pValueLen --;
@@ -1309,22 +1201,20 @@ int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
        }
 
        else if (!strcasecmp(key, "In-reply-to")) {
-               if (CM_IsEmpty(msg, eWeferences)) /* References: supersedes In-reply-to: */
+               if (CM_IsEmpty(msg, eWeferences)) // References: supersedes In-reply-to:
                        CM_SetField(msg, eWeferences, value, valuelen);
                processed = 1;
        }
 
 
 
-       /* Clean up and move on. */
-       free(key);      /* Don't free 'value', it's actually the same buffer */
+       // Clean up and move on.
+       free(key);      // Don't free 'value', it's actually the same buffer
        return processed;
 }
 
 
-/*
- * Convert RFC822 references format (References) to Citadel references format (Weferences)
- */
+// Convert RFC822 references format (References) to Citadel references format (Weferences)
 void convert_references_to_wefewences(char *str) {
        int bracket_nesting = 0;
        char *ptr = str;
@@ -1357,13 +1247,11 @@ void convert_references_to_wefewences(char *str) {
 }
 
 
-/*
- * Convert an RFC822 message (headers + body) to a CtdlMessage structure.
- * NOTE: the supplied buffer becomes part of the CtdlMessage structure, and
- * will be deallocated when CM_Free() is called.  Therefore, the
- * supplied buffer should be DEREFERENCED.  It should not be freed or used
- * again.
- */
+// Convert an RFC822 message (headers + body) to a CtdlMessage structure.
+// NOTE: the supplied buffer becomes part of the CtdlMessage structure, and
+// will be deallocated when CM_Free() is called.  Therefore, the
+// supplied buffer should be DEREFERENCED.  It should not be freed or used
+// again.
 struct CtdlMessage *convert_internet_message(char *rfc822) {
        StrBuf *RFCBuf = NewStrBufPlain(rfc822, -1);
        free (rfc822);
@@ -1371,7 +1259,6 @@ struct CtdlMessage *convert_internet_message(char *rfc822) {
 }
 
 
-
 struct CtdlMessage *convert_internet_message_buf(StrBuf **rfc822)
 {
        struct CtdlMessage *msg;
@@ -1384,9 +1271,9 @@ struct CtdlMessage *convert_internet_message_buf(StrBuf **rfc822)
        if (msg == NULL) return msg;
 
        memset(msg, 0, sizeof(struct CtdlMessage));
-       msg->cm_magic = CTDLMESSAGE_MAGIC;      /* self check */
-       msg->cm_anon_type = 0;                  /* never anonymous */
-       msg->cm_format_type = FMT_RFC822;       /* internet message */
+       msg->cm_magic = CTDLMESSAGE_MAGIC;      // self check
+       msg->cm_anon_type = 0;                  // never anonymous
+       msg->cm_format_type = FMT_RFC822;       // internet message
 
        pos = ChrPtr(*rfc822);
        totalend = pos + StrLength(*rfc822);
@@ -1466,7 +1353,6 @@ struct CtdlMessage *convert_internet_message_buf(StrBuf **rfc822)
 }
 
 
-
 /*
  * Look for a particular header field in an RFC822 message text.  If the
  * requested field is found, it is unfolded (if necessary) and returned to
@@ -1518,7 +1404,6 @@ char *rfc822_fetch_field(const char *rfc822, const char *fieldname) {
 }
 
 
-
 /*****************************************************************************
  *                      DIRECTORY MANAGEMENT FUNCTIONS                       *
  *****************************************************************************/
@@ -1538,13 +1423,12 @@ void directory_key(char *key, char *addr) {
        }
        key[keylen++] = 0;
 
-       syslog(LOG_DEBUG, "Directory key is <%s>\n", key);
+       syslog(LOG_DEBUG, "internet_addressing: directory key is <%s>", key);
 }
 
 
-
-/* Return nonzero if the supplied address is in a domain we keep in
- * the directory
+/*
+ * Return nonzero if the supplied address is in one of "our" domains
  */
 int IsDirectory(char *addr, int allow_masq_domains) {
        char domain[256];
@@ -1558,7 +1442,7 @@ int IsDirectory(char *addr, int allow_masq_domains) {
        if ( (h == hostalias_masq) && allow_masq_domains)
                return(1);
        
-       if ( (h == hostalias_localhost) || (h == hostalias_directory) ) {
+       if (h == hostalias_localhost) {
                return(1);
        }
        else {
@@ -1567,23 +1451,16 @@ int IsDirectory(char *addr, int allow_masq_domains) {
 }
 
 
-/*
- * Initialize the directory database (erasing anything already there)
- */
-void CtdlDirectoryInit(void) {
-       cdb_trunc(CDB_DIRECTORY);
-}
-
-
 /*
  * Add an Internet e-mail address to the directory for a user
  */
 int CtdlDirectoryAddUser(char *internet_addr, char *citadel_addr) {
        char key[SIZ];
 
-       if (IsDirectory(internet_addr, 0) == 0) 
+       if (IsDirectory(internet_addr, 0) == 0) {
                return 0;
-       syslog(LOG_DEBUG, "Create directory entry: %s --> %s\n", internet_addr, citadel_addr);
+       }
+       syslog(LOG_DEBUG, "internet_addressing: create directory entry: %s --> %s", internet_addr, citadel_addr);
        directory_key(key, internet_addr);
        cdb_store(CDB_DIRECTORY, key, strlen(key), citadel_addr, strlen(citadel_addr)+1 );
        return 1;
@@ -1598,8 +1475,8 @@ int CtdlDirectoryAddUser(char *internet_addr, char *citadel_addr) {
  */
 int CtdlDirectoryDelUser(char *internet_addr, char *citadel_addr) {
        char key[SIZ];
-
-       syslog(LOG_DEBUG, "Delete directory entry: %s --> %s\n", internet_addr, citadel_addr);
+       
+       syslog(LOG_DEBUG, "internet_addressing: delete directory entry: %s --> %s", internet_addr, citadel_addr);
        directory_key(key, internet_addr);
        return cdb_delete(CDB_DIRECTORY, key, strlen(key) ) == 0;
 }
@@ -1615,7 +1492,9 @@ int CtdlDirectoryLookup(char *target, char *internet_addr, size_t targbuflen) {
        char key[SIZ];
 
        /* Dump it in there unchanged, just for kicks */
-       safestrncpy(target, internet_addr, targbuflen);
+       if (target != NULL) {
+               safestrncpy(target, internet_addr, targbuflen);
+       }
 
        /* Only do lookups for addresses with hostnames in them */
        if (num_tokens(internet_addr, '@') != 2) return(-1);
@@ -1626,7 +1505,9 @@ int CtdlDirectoryLookup(char *target, char *internet_addr, size_t targbuflen) {
        directory_key(key, internet_addr);
        cdbrec = cdb_fetch(CDB_DIRECTORY, key, strlen(key) );
        if (cdbrec != NULL) {
-               safestrncpy(target, cdbrec->ptr, targbuflen);
+               if (target != NULL) {
+                       safestrncpy(target, cdbrec->ptr, targbuflen);
+               }
                cdb_free(cdbrec);
                return(0);
        }
@@ -1684,7 +1565,7 @@ char *harvest_collected_addresses(struct CtdlMessage *msg) {
                                        utf8ify_rfc822_string(addr);
                                process_rfc822_addr(addr, user, node, name);
                                h = CtdlHostAlias(node);
-                               if ( (h != hostalias_localhost) && (h != hostalias_directory) ) {
+                               if (h != hostalias_localhost) {
                                        coll = realloc(coll, strlen(coll) + strlen(addr) + 4);
                                        if (coll == NULL) return(NULL);
                                        if (!IsEmptyStr(coll)) {
@@ -1705,10 +1586,136 @@ char *harvest_collected_addresses(struct CtdlMessage *msg) {
 }
 
 
-CTDL_MODULE_INIT(internet_addressing)
-{
-       if (!threading) {
-               CtdlRegisterProtoHook(cmd_isme, "ISME", "Determine whether an email address belongs to a user");
+/*
+ * Helper function for CtdlRebuildDirectoryIndex()
+ */
+void CtdlRebuildDirectoryIndex_backend(char *username, void *data) {
+
+       int j = 0;
+       struct ctdluser usbuf;
+
+       if (CtdlGetUser(&usbuf, username) != 0) {
+               return;
+       }
+
+       if ( (!IsEmptyStr(usbuf.fullname)) && (!IsEmptyStr(usbuf.emailaddrs)) ) {
+               for (j=0; j<num_tokens(usbuf.emailaddrs, '|'); ++j) {
+                       char one_email[512];
+                       extract_token(one_email, usbuf.emailaddrs, j, '|', sizeof one_email);
+                       CtdlDirectoryAddUser(one_email, usbuf.fullname);
+               }
+       }
+}
+
+
+/*
+ * Initialize the directory database (erasing anything already there)
+ */
+void CtdlRebuildDirectoryIndex(void) {
+       syslog(LOG_INFO, "internet_addressing: rebuilding email address directory index");
+       cdb_trunc(CDB_DIRECTORY);
+       ForEachUser(CtdlRebuildDirectoryIndex_backend, NULL);
+}
+
+
+// Configure Internet email addresses for a user account, updating the Directory Index in the process
+void CtdlSetEmailAddressesForUser(char *requested_user, char *new_emailaddrs) {
+       struct ctdluser usbuf;
+       int i;
+       char buf[SIZ];
+
+       if (CtdlGetUserLock(&usbuf, requested_user) != 0) {     // We can lock because the DirectoryIndex functions don't lock.
+               return;                                         // Silently fail here if the specified user does not exist.
+       }
+
+       syslog(LOG_DEBUG, "internet_addressing: setting email addresses for <%s> to <%s>", usbuf.fullname, new_emailaddrs);
+
+       // Delete all of the existing directory index records for the user (easier this way)
+       for (i=0; i<num_tokens(usbuf.emailaddrs, '|'); ++i) {
+               extract_token(buf, usbuf.emailaddrs, i, '|', sizeof buf);
+               CtdlDirectoryDelUser(buf, requested_user);
+       }
+
+       strcpy(usbuf.emailaddrs, new_emailaddrs);               // make it official.
+
+       // Index all of the new email addresses (they've already been sanitized)
+       for (i=0; i<num_tokens(usbuf.emailaddrs, '|'); ++i) {
+               extract_token(buf, usbuf.emailaddrs, i, '|', sizeof buf);
+               CtdlDirectoryAddUser(buf, requested_user);
+       }
+
+       CtdlPutUserLock(&usbuf);
+}
+
+
+/*
+ * Auto-generate an Internet email address for a user account
+ */
+void AutoGenerateEmailAddressForUser(struct ctdluser *user) {
+       char synthetic_email_addr[1024];
+       int i, j;
+       int u = 0;
+
+       for (i=0; u==0; ++i) {
+               if (i == 0) {
+                       // first try just converting the user name to lowercase and replacing spaces with underscores
+                       snprintf(synthetic_email_addr, sizeof synthetic_email_addr, "%s@%s", user->fullname, CtdlGetConfigStr("c_fqdn"));
+                       for (j=0; ((synthetic_email_addr[j] != '\0')&&(synthetic_email_addr[j] != '@')); j++) {
+                               synthetic_email_addr[j] = tolower(synthetic_email_addr[j]);
+                               if (!isalnum(synthetic_email_addr[j])) {
+                                       synthetic_email_addr[j] = '_';
+                               }
+                       }
+               }
+               else if (i == 1) {
+                       // then try 'ctdl' followed by the user number
+                       snprintf(synthetic_email_addr, sizeof synthetic_email_addr, "ctdl%08lx@%s", user->usernum, CtdlGetConfigStr("c_fqdn"));
+               }
+               else if (i > 1) {
+                       // oof.  just keep trying other numbers until we find one
+                       snprintf(synthetic_email_addr, sizeof synthetic_email_addr, "ctdl%08x@%s", i, CtdlGetConfigStr("c_fqdn"));
+               }
+               u = CtdlDirectoryLookup(NULL, synthetic_email_addr, 0);
+               syslog(LOG_DEBUG, "user_ops: address <%s> lookup returned <%d>", synthetic_email_addr, u);
        }
-       return "internet_addressing";
+
+       CtdlSetEmailAddressesForUser(user->fullname, synthetic_email_addr);
+       strncpy(CC->user.emailaddrs, synthetic_email_addr, sizeof(user->emailaddrs));
+       syslog(LOG_DEBUG, "user_ops: auto-generated email address <%s> for <%s>", synthetic_email_addr, user->fullname);
+}
+
+
+// Determine whether the supplied email address is subscribed to the supplied room's mailing list service.
+int is_email_subscribed_to_list(char *email, char *room_name) {
+       struct ctdlroom room;
+       long roomnum;
+       char *roomnetconfig;
+       int found_it = 0;
+
+       if (CtdlGetRoom(&room, room_name)) {
+               return(0);                                      // room not found, so definitely not subscribed
+       }
+
+       // If this room has the QR2_SMTP_PUBLIC flag set, anyone may email a post to this room, even non-subscribers.
+       if (room.QRflags2 & QR2_SMTP_PUBLIC) {
+               return(1);
+       }
+
+       roomnum = room.QRnumber;
+       roomnetconfig = LoadRoomNetConfigFile(roomnum);
+       if (roomnetconfig == NULL) {
+               return(0);
+       }
+
+       // We're going to do a very sloppy match here and simply search for the specified email address
+       // anywhere in the room's netconfig.  If you don't like this, fix it yourself.
+       if (bmstrcasestr(roomnetconfig, email)) {
+               found_it = 1;
+       }
+       else {
+               found_it = 0;
+       }
+
+       free(roomnetconfig);
+       return(found_it);
 }