From a7151621005861c28d5ed726229c5ad2d5a57eec Mon Sep 17 00:00:00 2001
From: "Steffen (Daode) Nurpmeso" <steffen@sdaoden.eu>
Date: Wed, 28 Sep 2016 16:05:16 +0200
Subject: [PATCH] Add a RFC 6068 url_mailto_to_address() hack for List-Post:

---
 cmd3.c       | 14 ++++++--------
 mime_param.c |  2 +-
 nailfuns.h   |  6 +++++-
 nam_a_grp.c  |  4 ++--
 urlcrecry.c  | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 70 insertions(+), 12 deletions(-)

diff --git a/cmd3.c b/cmd3.c
index 397930cf1..18574165d 100644
--- a/cmd3.c
+++ b/cmd3.c
@@ -314,15 +314,13 @@ jnext_msg:
    if (mft != NULL || (hf & HF_LIST_REPLY) || ok_blook(followup_to)) {
       /* Learn about a possibly sending mailing list; use do for break; */
       if ((cp = hfield1("list-post", mp)) != NULL) do {
-         struct name *x = lextract(cp, GEXTRA | GSKIN);
-         if (x == NULL || x->n_flink != NULL ||
-               !is_prefix("mailto:", x->n_name) ||
-               /* XXX the mailto: prefix causes failure (":" invalid character)
-                * XXX which is why need to recreate a struct name with an
-                * XXX updated name; this is terribly wasteful and can't we find
+         struct name *x;
+
+         if ((x = lextract(cp, GEXTRA | GSKIN)) == NULL || x->n_flink != NULL ||
+               (cp = url_mailto_to_address(x->n_name)) == NULL ||
+               /* XXX terribly wasteful to create a new name, and can't we find
                 * XXX a way to mitigate that?? */
-               is_addr_invalid(x = nalloc(x->n_name + sizeof("mailto:") -1,
-                  GEXTRA | GSKIN), EACM_STRICT)) {
+               is_addr_invalid(x = nalloc(cp, GEXTRA | GSKIN), EACM_STRICT)) {
             if (options & OPT_D_V)
                n_err(_("Message contains invalid \"List-Post:\" header\n"));
             cp = NULL;
diff --git a/mime_param.c b/mime_param.c
index 5e4883c05..4ea2b2e28 100644
--- a/mime_param.c
+++ b/mime_param.c
@@ -466,7 +466,7 @@ __rfc2231_join(struct rfc2231_joiner *head, char **result, char const **emsg)
                cp += 2;
                i -= 3;
             } else {
-   jhex_putc:
+jhex_putc:
                sin.s[sin.l++] = c;
                --i;
             }
diff --git a/nailfuns.h b/nailfuns.h
index 8100849f1..0c02df159 100644
--- a/nailfuns.h
+++ b/nailfuns.h
@@ -1429,7 +1429,7 @@ FL char const * mime_type_mimepart_handler(struct mimepart const *mpp);
 
 /* Allocate a single element of a name list, initialize its name field to the
  * passed name and return it */
-FL struct name * nalloc(char *str, enum gfield ntype);
+FL struct name * nalloc(char const *str, enum gfield ntype);
 
 /* Like nalloc(), but initialize from content of np */
 FL struct name * ndup(struct name *np, enum gfield ntype);
@@ -2081,6 +2081,10 @@ FL char *      urlxdec(char const *cp SALLOC_DEBUG_ARGS);
 # define urlxdec(CP)             urlxdec(CP, __FILE__, __LINE__)
 #endif
 
+/* Parse a RFC 6058 'mailto' URI to a single to: (TODO yes, for now hacky).
+ * Return NULL or something that can be converted to a struct name */
+FL char *      url_mailto_to_address(char const *mailtop);
+
 #ifdef HAVE_SOCKETS
 /* Return port of urlp->url_proto (and set irv_or_null), or NULL if unknown */
 FL char const * url_servbyname(struct url const *urlp, ui16_t *irv_or_null);
diff --git a/nam_a_grp.c b/nam_a_grp.c
index 9b5df867a..cfeb04f29 100644
--- a/nam_a_grp.c
+++ b/nam_a_grp.c
@@ -886,7 +886,7 @@ _mlmux_linkout(struct group *gp)
 #endif /* HAVE_REGEX */
 
 FL struct name *
-nalloc(char *str, enum gfield ntype)
+nalloc(char const *str, enum gfield ntype)
 {
    struct addrguts ag;
    struct str in, out;
@@ -954,7 +954,7 @@ jskipfullextra:
 #ifdef HAVE_IDNA
       if (!(ag.ag_n_flags & NAME_IDNA)) {
 #endif
-         in.s = str;
+         in.s = UNCONST(str);
          in.l = ag.ag_ilen;
 #ifdef HAVE_IDNA
       } else {
diff --git a/urlcrecry.c b/urlcrecry.c
index f7aebbfd5..174a964a6 100644
--- a/urlcrecry.c
+++ b/urlcrecry.c
@@ -587,6 +587,62 @@ FL char *
    return n;
 }
 
+FL char *
+url_mailto_to_address(char const *mailtop){ /* TODO hack! RFC 6068; factory? */
+   size_t i;
+   char *rv;
+   char const *mailtop_orig;
+   NYD_ENTER;
+
+   if(!is_prefix("mailto:", mailtop_orig = mailtop)){
+      rv = NULL;
+      goto jleave;
+   }
+   mailtop += sizeof("mailto:") -1;
+
+   /* TODO This is all intermediate, and for now just enough to understand
+    * TODO a little bit of a little more advanced List-Post: headers. */
+   /* Strip any hfield additions, keep only to addr-spec's */
+   if((rv = strchr(mailtop, '?')) != NULL)
+      rv = savestrbuf(mailtop, i = PTR2SIZE(rv - mailtop));
+   else
+      rv = savestrbuf(mailtop, i = strlen(mailtop));
+
+   i = strlen(rv);
+
+   /* Simply perform percent-decoding if there is a percent % */
+   if(memchr(rv, '%', i) != NULL){
+      char *rv_base;
+      bool_t err;
+
+      for(err = FAL0, mailtop = rv_base = rv; i > 0;){
+         char c;
+
+         if((c = *mailtop++) == '%'){
+            si32_t cc;
+
+            if(i < 3 || (cc = mime_hexseq_to_char(mailtop)) < 0){
+               if(!err && (err = TRU1, options & OPT_D_V))
+                  n_err(_("Invalid RFC 6068 'mailto' URL: %s\n"), mailtop_orig);
+               goto jhex_putc;
+            }
+            *rv++ = (char)cc;
+            mailtop += 2;
+            i -= 3;
+         }else{
+jhex_putc:
+            *rv++ = c;
+            --i;
+         }
+      }
+      *rv = '\0';
+      rv = rv_base;
+   }
+jleave:
+   NYD_LEAVE;
+   return rv;
+}
+
 #ifdef HAVE_SOCKETS /* Note: not indented for that -- later: file:// etc.! */
 FL char const *
 url_servbyname(struct url const *urlp, ui16_t *irv_or_null)
-- 
2.11.4.GIT