From dac762a702d01c8c2d42135795cc9bf23ff324a2 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Wed, 11 Jan 2017 20:16:45 +0100 Subject: [PATCH] wget: fix for brain-damaged HTTP servers. Closes 9471 write(3, "GET / HTTP/1.1\r\nUser-Agent: Wget\r\nConnection: close\r\n\r\n", 74) = 74 shutdown(3, SHUT_WR) = 0 alarm(900) = 900 read(3, "", 1024) = 0 write(2, "wget: error getting response\n", 29) = 29 exit(1) The peer simply does not return anything. It closes its connection. Probably it detects wget closing its writing end: shutdown(3, SHUT_WR). The point it, closing write side of the socket is _valid_ for HTTP. wget sent the full request, it won't be sending anything more: it will only receive the response, and that's it. Signed-off-by: Denys Vlasenko --- networking/wget.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) diff --git a/networking/wget.c b/networking/wget.c index b082a0f59..afb09f587 100644 --- a/networking/wget.c +++ b/networking/wget.c @@ -141,6 +141,8 @@ #endif +#define SSL_SUPPORTED (ENABLE_FEATURE_WGET_OPENSSL || ENABLE_FEATURE_WGET_SSL_HELPER) + struct host_info { char *allocated; const char *path; @@ -151,7 +153,7 @@ struct host_info { }; static const char P_FTP[] ALIGN1 = "ftp"; static const char P_HTTP[] ALIGN1 = "http"; -#if ENABLE_FEATURE_WGET_OPENSSL || ENABLE_FEATURE_WGET_SSL_HELPER +#if SSL_SUPPORTED static const char P_HTTPS[] ALIGN1 = "https"; #endif @@ -452,7 +454,7 @@ static void parse_url(const char *src_url, struct host_info *h) if (strcmp(url, P_FTP) == 0) { h->port = bb_lookup_port(P_FTP, "tcp", 21); } else -#if ENABLE_FEATURE_WGET_OPENSSL || ENABLE_FEATURE_WGET_SSL_HELPER +#if SSL_SUPPORTED if (strcmp(url, P_HTTPS) == 0) { h->port = bb_lookup_port(P_HTTPS, "tcp", 443); h->protocol = P_HTTPS; @@ -1093,12 +1095,20 @@ static void download_one_url(const char *url) } fflush(sfp); - /* If we use SSL helper, keeping our end of the socket open for writing - * makes our end (i.e. the same fd!) readable (EAGAIN instead of EOF) - * even after child closes its copy of the fd. - * This helps: - */ - shutdown(fileno(sfp), SHUT_WR); + +/* Tried doing this unconditionally. + * Cloudflare and nginx/1.11.5 are shocked to see SHUT_WR on non-HTTPS. + */ +#if SSL_SUPPORTED + if (target.protocol == P_HTTPS) { + /* If we use SSL helper, keeping our end of the socket open for writing + * makes our end (i.e. the same fd!) readable (EAGAIN instead of EOF) + * even after child closes its copy of the fd. + * This helps: + */ + shutdown(fileno(sfp), SHUT_WR); + } +#endif /* * Retrieve HTTP response line and check for "200" status code. -- 2.25.1