Adjust HTTP header parsing to follow RFC more closely.

RFC9112 allows any amount of space/tabs between the ':' and the value.
Until now this code required exactly one space which works most of the
time but is not RFC compliant.
OK djm@

diff --git a/usr.bin/ftp/fetch.c b/usr.bin/ftp/fetch.c
index ebc7498..a494e5a 100644 (file)
--- a/usr.bin/ftp/fetch.c
+++ b/usr.bin/ftp/fetch.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: fetch.c,v 1.208 2021/11/10 07:32:55 kn Exp $  */
+/*     $OpenBSD: fetch.c,v 1.209 2022/09/08 11:12:44 claudio Exp $     */
 /*     $NetBSD: fetch.c,v 1.14 1997/08/18 10:20:20 lukem Exp $ */
 
 /*-
@@ -905,12 +905,11 @@ noslash:
 
                /* Look for some headers */
                cp = buf;
-#define CONTENTLEN "Content-Length: "
+#define CONTENTLEN "Content-Length:"
                if (strncasecmp(cp, CONTENTLEN, sizeof(CONTENTLEN) - 1) == 0) {
-                       size_t s;
                        cp += sizeof(CONTENTLEN) - 1;
-                       if ((s = strcspn(cp, " \t")))
-                               *(cp+s) = 0;
+                       cp += strspn(cp, " \t");
+                       cp[strcspn(cp, " \t")] = '\0';
                        filesize = strtonum(cp, 0, LLONG_MAX, &errstr);
                        if (errstr != NULL)
                                goto improper;
@@ -918,10 +917,11 @@ noslash:
                        if (restart_point)
                                filesize += restart_point;
 #endif /* !SMALL */
-#define LOCATION "Location: "
+#define LOCATION "Location:"
                } else if (isredirect &&
                    strncasecmp(cp, LOCATION, sizeof(LOCATION) - 1) == 0) {
                        cp += sizeof(LOCATION) - 1;
+                       cp += strspn(cp, " \t");
                        /*
                         * If there is a colon before the first slash, this URI
                         * is not relative. RFC 3986 4.2
@@ -974,25 +974,26 @@ noslash:
                        rval = url_get(redirurl, proxyenv, savefile, lastfile);
                        free(redirurl);
                        goto cleanup_url_get;
-#define RETRYAFTER "Retry-After: "
+#define RETRYAFTER "Retry-After:"
                } else if (isunavail &&
                    strncasecmp(cp, RETRYAFTER, sizeof(RETRYAFTER) - 1) == 0) {
                        size_t s;
                        cp += sizeof(RETRYAFTER) - 1;
-                       if ((s = strcspn(cp, " \t")))
-                               cp[s] = '\0';
+                       cp += strspn(cp, " \t");
+                       cp[strcspn(cp, " \t")] = '\0';
                        retryafter = strtonum(cp, 0, 0, &errstr);
                        if (errstr != NULL)
                                retryafter = -1;
-#define TRANSFER_ENCODING "Transfer-Encoding: "
+#define TRANSFER_ENCODING "Transfer-Encoding:"
                } else if (strncasecmp(cp, TRANSFER_ENCODING,
                            sizeof(TRANSFER_ENCODING) - 1) == 0) {
                        cp += sizeof(TRANSFER_ENCODING) - 1;
+                       cp += strspn(cp, " \t");
                        cp[strcspn(cp, " \t")] = '\0';
                        if (strcasecmp(cp, "chunked") == 0)
                                chunked = 1;
 #ifndef SMALL
-#define LAST_MODIFIED "Last-Modified: "
+#define LAST_MODIFIED "Last-Modified:"
                } else if (strncasecmp(cp, LAST_MODIFIED,
                            sizeof(LAST_MODIFIED) - 1) == 0) {
                        cp += sizeof(LAST_MODIFIED) - 1;