Re: [PATCH v2 08/15] efi_loader: device_path: add support for HTTP device path

On Fri, 8 Nov 2024 at 15:40, Adriano Cordova adrianox@gmail.com wrote:

Add efi_dp_from_http to form a device path from HTTP. The device path is the concatenation of the device path returned by efi_dp_from_ipv4 together with an URI node and an END node.

Signed-off-by: Adriano Cordova adrianox@gmail.com

include/efi_loader.h | 1 + lib/efi_loader/efi_device_path.c | 51 ++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+)

diff --git a/include/efi_loader.h b/include/efi_loader.h index 44d29e7967..ab79364857 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -872,6 +872,7 @@ struct efi_device_path *efi_dp_part_node(struct blk_desc *desc, int part); struct efi_device_path *efi_dp_from_file(const struct efi_device_path *dp, const char *path); struct efi_device_path *efi_dp_from_eth(void); +struct efi_device_path *efi_dp_from_http(const char *server); struct efi_device_path *efi_dp_from_mem(uint32_t mem_type, uint64_t start_address, uint64_t end_address); diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c index 3e02341224..dc79a61196 100644 --- a/lib/efi_loader/efi_device_path.c +++ b/lib/efi_loader/efi_device_path.c @@ -1012,6 +1012,57 @@ struct efi_device_path *efi_dp_from_ipv4(struct efi_ipv4_address *ip, return dp2; }

+struct efi_device_path *efi_dp_from_http(const char *server) +{

•   struct efi_device_path *dp1, *dp2;
  

•   struct efi_device_path_uri *uridp;
  

•   efi_uintn_t uridp_len;
  

•   char *pos;
  

•   char tmp[128];
  

•   struct efi_ipv4_address ip;
  

•   struct efi_ipv4_address mask;
  

•   efi_net_get_addr(&ip, &mask, NULL);
  

•   dp1 = efi_dp_from_ipv4(&ip, &mask, NULL);
  

•   strcpy(tmp, "http://");
  

•   if (server) {
  

•           memcpy(tmp + strlen("http://"), server, strlen(server) + 1);
  

We need some sanity checking here, since the server name is a user input and might overflow tmp

•   } else {
  

+#ifdef CONFIG_NET_LWIP

#iif IS_ENABLED is preferred here

•           // The lwip stack does not set env variables for server
  

•           efi_free_pool(dp1);
  

•           return NULL;
  

Can you move this checking on top? You can avoid alloc/free buffers is LWIP is enabled and we domnt have a server

+#else

•           ip_to_string(net_server_ip, tmp + strlen("http://"));
  

+#endif

•   }
  

•   uridp_len = sizeof(struct efi_device_path) + strlen(tmp) + 1;
  

•   uridp = efi_alloc(uridp_len + sizeof(END));
  

•   if (!uridp) {
  

•           log_err("Out of memory\n");
  

•           return NULL;
  

•   }
  

•   uridp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
  

•   uridp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_URI;
  

•   uridp->dp.length = uridp_len;
  

•   debug("device path: setting uri device path to %s\n", tmp);
  

•   memcpy(uridp->uri, tmp, strlen(tmp) + 1);
  

•   pos = (char *)uridp + uridp_len;
  

•   memcpy(pos, &END, sizeof(END));
  

•   dp2 = efi_dp_concat(dp1, (const struct efi_device_path *)uridp, 0);
  

•   efi_free_pool(uridp);
  

•   efi_free_pool(dp1);
  

•   return dp2;
  

+}

/* Construct a device-path for memory-mapped image */ struct efi_device_path *efi_dp_from_mem(uint32_t memory_type, uint64_t start_address, -- 2.43.0

Thanks /Ilias