On Fri, May 06, 2022 at 09:55:53PM +0100, Nikos Nikoleris wrote:
> This change adds support for discovering the command line arguments,
> as a string. Then, we parse this string to populate __argc and __argv
> for EFI tests.
>
> Signed-off-by: Nikos Nikoleris <nikos.nikoleris@xxxxxxx>
> ---
> lib/linux/efi.h | 39 +++++++++++++++
> lib/stdlib.h | 1 +
> lib/efi.c | 123 ++++++++++++++++++++++++++++++++++++++++++++++++
> lib/string.c | 2 +-
> 4 files changed, 164 insertions(+), 1 deletion(-)
>
> diff --git a/lib/linux/efi.h b/lib/linux/efi.h
> index 455625a..e3aba1d 100644
> --- a/lib/linux/efi.h
> +++ b/lib/linux/efi.h
> @@ -60,6 +60,10 @@ typedef guid_t efi_guid_t;
>
> #define ACPI_TABLE_GUID EFI_GUID(0xeb9d2d30, 0x2d88, 0x11d3, 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
>
> +#define LOADED_IMAGE_PROTOCOL_GUID EFI_GUID(0x5b1b31a1, 0x9562, 0x11d2, 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
> +
> +#define efi_table_attr(inst, attr) (inst->attr)
> +
> typedef struct {
> efi_guid_t guid;
> void *table;
> @@ -416,6 +420,41 @@ struct efi_boot_memmap {
> unsigned long *buff_size;
> };
>
> +#define __aligned_u64 u64 __attribute__((aligned(8)))
> +
> +typedef union {
> + struct {
> + u32 revision;
> + efi_handle_t parent_handle;
> + efi_system_table_t *system_table;
> + efi_handle_t device_handle;
> + void *file_path;
> + void *reserved;
> + u32 load_options_size;
> + void *load_options;
> + void *image_base;
> + __aligned_u64 image_size;
> + unsigned int image_code_type;
> + unsigned int image_data_type;
> + efi_status_t (__efiapi *unload)(efi_handle_t image_handle);
> + };
> + struct {
> + u32 revision;
> + u32 parent_handle;
> + u32 system_table;
> + u32 device_handle;
> + u32 file_path;
> + u32 reserved;
> + u32 load_options_size;
> + u32 load_options;
> + u32 image_base;
> + __aligned_u64 image_size;
> + u32 image_code_type;
> + u32 image_data_type;
> + u32 unload;
> + } mixed_mode;
> +} efi_loaded_image_t;
Is the 32-bit mode used (in later commits)? Why not reuse
efi_loaded_image_64_t only and make sure it's the one expected.
> +
> #define efi_bs_call(func, ...) efi_system_table->boottime->func(__VA_ARGS__)
> #define efi_rs_call(func, ...) efi_system_table->runtime->func(__VA_ARGS__)
>
> diff --git a/lib/stdlib.h b/lib/stdlib.h
> index 28496d7..2c524d7 100644
> --- a/lib/stdlib.h
> +++ b/lib/stdlib.h
> @@ -7,6 +7,7 @@
> #ifndef _STDLIB_H_
> #define _STDLIB_H_
>
> +int isspace(int c);
> long int strtol(const char *nptr, char **endptr, int base);
> unsigned long int strtoul(const char *nptr, char **endptr, int base);
> long long int strtoll(const char *nptr, char **endptr, int base);
> diff --git a/lib/efi.c b/lib/efi.c
> index 64cc978..5341942 100644
> --- a/lib/efi.c
> +++ b/lib/efi.c
> @@ -8,6 +8,7 @@
> */
>
> #include "efi.h"
> +#include <stdlib.h>
> #include <libcflat.h>
> #include <asm/setup.h>
>
> @@ -96,6 +97,97 @@ static void efi_exit(efi_status_t code)
> efi_rs_call(reset_system, EFI_RESET_SHUTDOWN, code, 0, NULL);
> }
>
> +static void efi_cmdline_to_argv(char *cmdline_ptr)
> +{
> + char *c = cmdline_ptr;
> + bool narg = true;
> + while (*c) {
> + if (isspace(*c)) {
> + *c = '\0';
> + narg = true;
> + } else if (narg) {
> + __argv[__argc++] = c;
> + narg = false;
> + }
> + c++;
> + }
> +}
> +
> +static char *efi_convert_cmdline(efi_loaded_image_t *image, int *cmd_line_len)
Mention that this was adapted from drivers/firmware/efi/libstub/efi-stub.c.
> +{
> + const u16 *s2;
> + unsigned long cmdline_addr = 0;
> + int options_chars = efi_table_attr(image, load_options_size) / 2;
> + const u16 *options = efi_table_attr(image, load_options);
> + int options_bytes = 0, safe_options_bytes = 0; /* UTF-8 bytes */
> + bool in_quote = false;
> + efi_status_t status;
> + const int COMMAND_LINE_SIZE = 2048;
> +
> + if (options) {
> + s2 = options;
> + while (options_bytes < COMMAND_LINE_SIZE && options_chars--) {
> + u16 c = *s2++;
> +
> + if (c < 0x80) {
> + if (c == L'\0' || c == L'\n')
> + break;
> + if (c == L'"')
> + in_quote = !in_quote;
> + else if (!in_quote && isspace((char)c))
> + safe_options_bytes = options_bytes;
> +
> + options_bytes++;
> + continue;
> + }
> +
> + /*
> + * Get the number of UTF-8 bytes corresponding to a
> + * UTF-16 character.
> + * The first part handles everything in the BMP.
> + */
> + options_bytes += 2 + (c >= 0x800);
> + /*
> + * Add one more byte for valid surrogate pairs. Invalid
> + * surrogates will be replaced with 0xfffd and take up
> + * only 3 bytes.
> + */
> + if ((c & 0xfc00) == 0xd800) {
> + /*
> + * If the very last word is a high surrogate,
> + * we must ignore it since we can't access the
> + * low surrogate.
> + */
> + if (!options_chars) {
> + options_bytes -= 3;
> + } else if ((*s2 & 0xfc00) == 0xdc00) {
> + options_bytes++;
> + options_chars--;
> + s2++;
> + }
> + }
> + }
> + if (options_bytes >= COMMAND_LINE_SIZE) {
> + options_bytes = safe_options_bytes;
> + printf("Command line is too long: truncated to %d bytes\n",
> + options_bytes);
> + }
> + }
> +
> + options_bytes++; /* NUL termination */
> +
> + status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, options_bytes,
> + (void **)&cmdline_addr);
> + if (status != EFI_SUCCESS)
> + return NULL;
> +
> + snprintf((char *)cmdline_addr, options_bytes, "%.*ls",
> + options_bytes - 1, options);
> +
> + *cmd_line_len = options_bytes;
> + return (char *)cmdline_addr;
> +}
> +
> efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab)
> {
> int ret;
> @@ -109,6 +201,37 @@ efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab)
> unsigned long map_size = 0, desc_size = 0, key = 0, buff_size = 0;
> u32 desc_ver;
>
> + /* Helper variables needed to get the cmdline */
> + efi_loaded_image_t *image;
> + efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
> + char *cmdline_ptr = NULL;
> + int cmdline_size = 0;
> +
> + /*
> + * Get a handle to the loaded image protocol. This is used to get
> + * information about the running image, such as size and the command
> + * line.
> + */
> + status = efi_bs_call(handle_protocol, handle, &loaded_image_proto,
> + (void *)&image);
> + if (status != EFI_SUCCESS) {
> + printf("Failed to get loaded image protocol\n");
> + goto efi_main_error;
> + }
> +
> + /*
> + * Get the command line from EFI, using the LOADED_IMAGE
> + * protocol. We are going to copy the command line into the
> + * device tree, so this can be allocated anywhere.
Does the "device tree" comment still make sense?
> + */
> + cmdline_ptr = efi_convert_cmdline(image, &cmdline_size);
> + if (!cmdline_ptr) {
> + printf("getting command line via LOADED_IMAGE_PROTOCOL\n");
> + status = EFI_OUT_OF_RESOURCES;
> + goto efi_main_error;
> + }
> + efi_cmdline_to_argv(cmdline_ptr);
> +
> /* Set up efi_bootinfo */
> efi_bootinfo.mem_map.map = ↦
> efi_bootinfo.mem_map.map_size = &map_size;
> diff --git a/lib/string.c b/lib/string.c
> index 27106da..b191ab1 100644
> --- a/lib/string.c
> +++ b/lib/string.c
> @@ -163,7 +163,7 @@ void *memchr(const void *s, int c, size_t n)
> return NULL;
> }
>
> -static int isspace(int c)
> +int isspace(int c)
> {
> return c == ' ' || c == '\t' || c == '\r' || c == '\n' || c == '\v' || c == '\f';
> }
> --
> 2.25.1
>
