From: Jerome Forissier Date: Mon, 18 Nov 2024 09:18:01 +0000 (+0100) Subject: doc: cmd: wget: document lwIP syntax X-Git-Url: http://git.dujemihanovic.xyz/img/%7B%7B%20%28.OutputFormats.Get?a=commitdiff_plain;h=5753b9eb489896dff63b5c40e1d526358abf6d7d;p=u-boot.git doc: cmd: wget: document lwIP syntax The lwIP version of wget supports a different syntax with a URL, in addition to the legacy syntax. Document that. While we're at it, fix a couple of minor issues in the legacy syntax: - hostIPaddr can be a DNS name if CONFIG_CMD_DNS is enabled - path is mandatory Signed-off-by: Jerome Forissier Reviewed-by: Simon Glass Reviewed-by: Heinrich Schuchardt --- diff --git a/doc/usage/cmd/wget.rst b/doc/usage/cmd/wget.rst index b8ca35bb14..48bedf1e84 100644 --- a/doc/usage/cmd/wget.rst +++ b/doc/usage/cmd/wget.rst @@ -11,29 +11,54 @@ Synopsis :: - wget address [[hostIPaddr:]path] + wget [address] [host:]path + wget [address] url # lwIP only + Description ----------- -The wget command is used to download a file from an HTTP server. +The wget command is used to download a file from an HTTP(S) server. +In order to use HTTPS you will need to compile wget with lwIP support. + +Legacy syntax +~~~~~~~~~~~~~ + +The legacy syntax is supported by the legacy network stack (CONFIG_NET=y) +as well as by the lwIP base network stack (CONFIG_NET_LWIP=y). It supports HTTP +only. -wget command will use HTTP over TCP to download files from an HTTP server. By default the destination port is 80 and the source port is pseudo-random. -The environment variable *httpdstp* can be used to set the destination port. +On the legacy nework stack the environment variable *httpdstp* can be used to +set the destination port address memory address for the data downloaded -hostIPaddr - IP address of the HTTP server, defaults to the value of environment - variable *serverip* +host + IP address (or host name if `CONFIG_CMD_DNS` is enabled) of the HTTP + server, defaults to the value of environment variable *serverip*. path path of the file to be downloaded. -Example -------- +New syntax (lwIP only) +~~~~~~~~~~~~~~~~~~~~~~ + +In addition to the syntax described above, wget accepts URLs if the network +stack is lwIP. + +address + memory address for the data downloaded + +url + HTTP or HTTPS URL, that is: http[s]://[:]/. + +Examples +-------- + +Example with the legacy network stack +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In the example the following steps are executed: @@ -52,13 +77,42 @@ In the example the following steps are executed: HTTP/1.0 302 Found Packets received 4, Transfer Successful +Example with lwIP +~~~~~~~~~~~~~~~~~ + +In the example the following steps are executed: + +* setup client network address +* download a file from the HTTPS server + +:: + + => dhcp + DHCP client bound to address 10.0.2.15 (3 ms) + => wget https://download.rockylinux.org/pub/rocky/9/isos/aarch64/Rocky-9.4-aarch64-minimal.iso + ########################################################################## + ########################################################################## + ########################################################################## + [...] + 1694892032 bytes transferred in 492181 ms (3.3 MiB/s) + Bytes transferred = 1694892032 (65060000 hex) + Configuration ------------- The command is only available if CONFIG_CMD_WGET=y. +To enable lwIP support set CONFIG_NET_LWIP=y. + +TCP Selective Acknowledgments in the legacy network stack can be enabled via +CONFIG_PROT_TCP_SACK=y. This will improve the download speed. Selective +Acknowledgments are enabled by default with lwIP. + +.. note:: -TCP Selective Acknowledgments can be enabled via CONFIG_PROT_TCP_SACK=y. -This will improve the download speed. + U-Boot currently has no way to verify certificates for HTTPS. + A place to store the root CA certificates is needed, and then MBed TLS would + need to walk the entire chain. Therefore, man-in-the middle attacks are + possible and HTTPS should not be relied upon for payload authentication. Return value ------------