fix authenticate

1 files changed, 31 insertions, 8 deletions

diff --git a/sirc.c b/sirc.c
index 37aa12c..7b7489f 100644
--- a/sirc.c
+++ b/sirc.c
@@ -608,8 +608,12 @@ static void handle_irc_line(int si, const char *raw) {
     if (strcmp(m.cmd,"CAP")==0) {
         char sub[16]="";
         if (m.nparams>=2) str_upper(sub, m.params[1], sizeof(sub));
-        if (strcmp(sub,"ACK")==0 && strstr(m.trail,"sasl")) {
-            srv_send_raw(si, "AUTHENTICATE PLAIN");
+        if (strcmp(sub,"ACK")==0) {
+            /* trail or last param may contain "sasl" */
+            const char *caps = m.trail[0] ? m.trail : m.params[m.nparams-1];
+            if (strstr(caps,"sasl")) {
+                srv_send_raw(si, "AUTHENTICATE PLAIN");
+            }
         } else if (strcmp(sub,"NAK")==0) {
             ev_simple(EV_ERROR, si, NULL, NULL, "Server rejected SASL CAP.");
             srv_sendf(si, "NICK %s", s->nick);
@@ -617,12 +621,31 @@ static void handle_irc_line(int si, const char *raw) {
         }
         return;
     }
-    if (strcmp(m.cmd,"AUTHENTICATE")==0 && strcmp(m.trail,"+")==0) {
-        char payload[512];
-        int plen=snprintf(payload,sizeof(payload),"%s%c%s%c%s",
-                          s->sasl_user,0,s->sasl_user,0,s->sasl_pass);
-        char enc[700]; base64_encode((unsigned char*)payload,plen,enc);
-        srv_sendf(si, "AUTHENTICATE %s", enc);
+    if (strcmp(m.cmd,"AUTHENTICATE")==0) {
+        /* server sends AUTHENTICATE + (trail or param) to prompt us */
+        const char *challenge = m.trail[0] ? m.trail :
+                                (m.nparams>0 ? m.params[0] : "");
+        if (strcmp(challenge,"+")==0) {
+            /* build PLAIN payload: authzid\0authcid\0passwd
+               must use memcpy — sasl_user/pass may not contain \0
+               but we need to embed \0 separators manually */
+            char payload[512];
+            int ulen = strlen(s->sasl_user);
+            int plen_pass = strlen(s->sasl_pass);
+            /* layout: [sasl_user]\0[sasl_user]\0[sasl_pass] */
+            int total = ulen + 1 + ulen + 1 + plen_pass;
+            if (total < (int)sizeof(payload)) {
+                int pos = 0;
+                memcpy(payload + pos, s->sasl_user, ulen); pos += ulen;
+                payload[pos++] = '\0';
+                memcpy(payload + pos, s->sasl_user, ulen); pos += ulen;
+                payload[pos++] = '\0';
+                memcpy(payload + pos, s->sasl_pass, plen_pass); pos += plen_pass;
+                char enc[700];
+                base64_encode((unsigned char*)payload, total, enc);
+                srv_sendf(si, "AUTHENTICATE %s", enc);
+            }
+        }
         return;
     }
     if (strcmp(m.cmd,"903")==0) {