# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1711764331 -10800
# Node ID d7fd0acdea64072cfb0891521e4d15a1e9935502
# Parent  c690a902bfeca54eed7dac5d74f2df1a90441914
Mail: handling of pipelined commands which cross buffer boundary.

Previously, pipelined commands which cross buffer boundary were rejected
as too long, even if the command itself was short enough to be handled
within the client buffer.

Fix is to move non-processed commands to the start of the buffer after
the previous command is fully processed.

diff -r c690a902bfec -r d7fd0acdea64 src/mail/ngx_mail_imap_handler.c
--- a/src/mail/ngx_mail_imap_handler.c	Sat Mar 30 05:05:05 2024 +0300
+++ b/src/mail/ngx_mail_imap_handler.c	Sat Mar 30 05:05:31 2024 +0300
@@ -102,6 +102,7 @@
 ngx_mail_imap_auth_state(ngx_event_t *rev)
 {
     u_char              *p;
+    size_t               n;
     ngx_int_t            rc;
     ngx_uint_t           tag;
     ngx_connection_t    *c;
@@ -285,6 +286,12 @@
             if (s->buffer->pos == s->buffer->last) {
                 s->buffer->pos = s->buffer->start;
                 s->buffer->last = s->buffer->start;
+
+            } else {
+                n = s->buffer->last - s->buffer->pos;
+                ngx_memmove(s->buffer->start, s->buffer->pos, n);
+                s->buffer->pos = s->buffer->start;
+                s->buffer->last = s->buffer->start + n;
             }
 
             s->tag.len = 0;
diff -r c690a902bfec -r d7fd0acdea64 src/mail/ngx_mail_pop3_handler.c
--- a/src/mail/ngx_mail_pop3_handler.c	Sat Mar 30 05:05:05 2024 +0300
+++ b/src/mail/ngx_mail_pop3_handler.c	Sat Mar 30 05:05:31 2024 +0300
@@ -119,6 +119,7 @@
 void
 ngx_mail_pop3_auth_state(ngx_event_t *rev)
 {
+    size_t               n;
     ngx_int_t            rc;
     ngx_connection_t    *c;
     ngx_mail_session_t  *s;
@@ -291,6 +292,12 @@
         if (s->buffer->pos == s->buffer->last) {
             s->buffer->pos = s->buffer->start;
             s->buffer->last = s->buffer->start;
+
+        } else {
+            n = s->buffer->last - s->buffer->pos;
+            ngx_memmove(s->buffer->start, s->buffer->pos, n);
+            s->buffer->pos = s->buffer->start;
+            s->buffer->last = s->buffer->start + n;
         }
 
         if (s->state) {
diff -r c690a902bfec -r d7fd0acdea64 src/mail/ngx_mail_smtp_handler.c
--- a/src/mail/ngx_mail_smtp_handler.c	Sat Mar 30 05:05:05 2024 +0300
+++ b/src/mail/ngx_mail_smtp_handler.c	Sat Mar 30 05:05:31 2024 +0300
@@ -430,6 +430,7 @@
 void
 ngx_mail_smtp_auth_state(ngx_event_t *rev)
 {
+    size_t               n;
     ngx_int_t            rc;
     ngx_connection_t    *c;
     ngx_mail_session_t  *s;
@@ -577,6 +578,12 @@
         if (s->buffer->pos == s->buffer->last) {
             s->buffer->pos = s->buffer->start;
             s->buffer->last = s->buffer->start;
+
+        } else {
+            n = s->buffer->last - s->buffer->pos;
+            ngx_memmove(s->buffer->start, s->buffer->pos, n);
+            s->buffer->pos = s->buffer->start;
+            s->buffer->last = s->buffer->start + n;
         }
 
         if (s->state) {