pxe, http: send the sysappend/ipappend strings as cookies

When using http, send the sysappend/ipappend strings as cookies
prefixed with _Syslinux_ ... the implementation of this may change.
This is using the "old" cookie format for compactness (single header,
for all cookies, and no $Version tag.)  PHP at least seems perfectly
happy to deal with it.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/core/fs/pxe/http.c b/core/fs/pxe/http.c
index f46cd4c..ae5e010 100644 (file)
--- a/core/fs/pxe/http.c
+++ b/core/fs/pxe/http.c
@@ -1,3 +1,4 @@
+#include <syslinux/sysappend.h>
 #include <ctype.h>
 #include <lwip/api.h>
 #include "pxe.h"
@@ -45,6 +46,83 @@ static bool append_ch(char *str, size_t size, size_t *pos, int ch)
     return success;
 }
 
+static size_t cookie_len;
+static char *cookie_buf;
+
+static size_t http_do_bake_cookies(char *q)
+{
+    static const char uchexchar[16] = "0123456789ABCDEF";
+    int i;
+    size_t len;
+    size_t n = 0;
+    const char *p;
+    char c;
+    size_t qlen = q ? -1UL : 0;
+    bool first = true;
+
+    for (i = 0; i < SYSAPPEND_MAX; i++) {
+       if ((p = sysappend_strings[i])) {
+           len = snprintf(q, qlen, "%s_Syslinux_", first ? "Cookie: " : "");
+           if (q)
+               q += len;
+           n += len;
+           first = false;
+           /* Copy string up to and including '=' */
+           do {
+               c = *p++;
+               if (q)
+                   *q++ = c;
+               n++;
+           } while (c != '=');
+           while ((c = *p++)) {
+               if (c == ' ') {
+                   if (q)
+                       *q++ = '+';
+                   n++;
+               } else if (is_token(c)) {
+                   if (q)
+                       *q++ = c;
+                   n++;
+               } else {
+                   if (q) {
+                       *q++ = '%';
+                       *q++ = uchexchar[c >> 4];
+                       *q++ = uchexchar[c & 15];
+                   }
+                   n += 3;
+               }
+           }
+           if (q)
+               *q++ = ';';
+           n++;
+       }
+    }
+    if (!first) {
+       if (q) {
+           *q++ = '\r';
+           *q++ = '\n';
+       }
+       n += 2;
+    }
+    if (q)
+       *q = '\0';
+    
+    return n;
+}
+
+void http_bake_cookies(void)
+{
+    if (cookie_buf)
+       free(cookie_buf);
+
+    cookie_len = http_do_bake_cookies(NULL);
+    cookie_buf = malloc(cookie_len+1);
+    if (!cookie_buf)
+       return;
+
+    http_do_bake_cookies(cookie_buf);
+}
+
 void http_open(struct url_info *url, struct inode *inode, const char **redir)
 {
     struct pxe_pvt_inode *socket = PVT(inode);
@@ -73,6 +151,10 @@ void http_open(struct url_info *url, struct inode *inode, const char **redir)
     int status;
     int pos;
 
+    /* XXX: make this an external call at the appropriate time instead */
+    if (!cookie_buf)
+       http_bake_cookies();
+
     socket->fill_buffer = tcp_fill_buffer;
     socket->close = tcp_close_file;
 
@@ -107,12 +189,15 @@ void http_open(struct url_info *url, struct inode *inode, const char **redir)
                           "Host: %s\r\n"
                           "User-Agent: PXELINUX/%s\r\n"
                           "Connection: close\r\n"
+                          "%s"
                           "\r\n",
-                          url->host, VERSION_STR);
+                          url->host, VERSION_STR,
+                          cookie_buf ? cookie_buf : "");
     if (header_len > sizeof header_buf)
        goto fail;              /* Buffer overflow */
 
-    err = netconn_write(socket->conn, header_buf, header_len, NETCONN_NOCOPY);
+    err = netconn_write(socket->conn, header_buf,
+                       header_len, NETCONN_NOCOPY);
     if (err) {
        printf("netconn_write error %d\n", err);
        goto fail;