diff options
author | Gerd Hoffmann <kraxel@redhat.com> | 2023-01-16 18:58:21 +0100 |
---|---|---|
committer | Gerd Hoffmann <kraxel@redhat.com> | 2023-01-18 14:32:14 +0100 |
commit | 53c368d71ba43da7414ac86c58291a11da05ba84 (patch) | |
tree | e0e387f36cd2ea24c483441868bdd495b35e2238 /src/boot/bootctl-uki.c | |
parent | ab250890c0483fab4ff78591e6c178b7c2257337 (diff) | |
download | systemd-53c368d71ba43da7414ac86c58291a11da05ba84.tar.gz |
bootctl: add kernel-identity command
The command takes a kernel as argument and checks what kind of kernel
the image is. Returns one of uki, pe or unknown.
Diffstat (limited to 'src/boot/bootctl-uki.c')
-rw-r--r-- | src/boot/bootctl-uki.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/src/boot/bootctl-uki.c b/src/boot/bootctl-uki.c new file mode 100644 index 0000000000..1a439afaae --- /dev/null +++ b/src/boot/bootctl-uki.c @@ -0,0 +1,110 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include "bootctl.h" +#include "bootctl-uki.h" +#include "fd-util.h" +#include "parse-util.h" +#include "pe-header.h" + +#define MAX_SECTIONS 96 + +static const uint8_t dos_file_magic[2] = "MZ"; +static const uint8_t pe_file_magic[4] = "PE\0\0"; + +static const uint8_t name_osrel[8] = ".osrel"; +static const uint8_t name_linux[8] = ".linux"; +static const uint8_t name_initrd[8] = ".initrd"; + +static int pe_sections(FILE *uki, struct PeSectionHeader **ret, size_t *ret_n) { + _cleanup_free_ struct PeSectionHeader *sections = NULL; + struct DosFileHeader dos; + struct PeHeader pe; + size_t scount; + uint64_t soff, items; + int rc; + + items = fread(&dos, 1, sizeof(dos), uki); + if (items != sizeof(dos)) + return log_error_errno(SYNTHETIC_ERRNO(EIO), "DOS header read error"); + if (memcmp(dos.Magic, dos_file_magic, sizeof(dos_file_magic)) != 0) + goto no_sections; + + rc = fseek(uki, le32toh(dos.ExeHeader), SEEK_SET); + if (rc < 0) + return log_error_errno(errno, "seek to PE header"); + items = fread(&pe, 1, sizeof(pe), uki); + if (items != sizeof(pe)) + return log_error_errno(SYNTHETIC_ERRNO(EIO), "PE header read error"); + if (memcmp(pe.Magic, pe_file_magic, sizeof(pe_file_magic)) != 0) + goto no_sections; + + soff = le32toh(dos.ExeHeader) + sizeof(pe) + le16toh(pe.FileHeader.SizeOfOptionalHeader); + rc = fseek(uki, soff, SEEK_SET); + if (rc < 0) + return log_error_errno(errno, "seek to PE section headers"); + + scount = le16toh(pe.FileHeader.NumberOfSections); + if (scount > MAX_SECTIONS) + goto no_sections; + sections = new(struct PeSectionHeader, scount); + if (!sections) + return log_oom(); + items = fread(sections, sizeof(*sections), scount, uki); + if (items != scount) + return log_error_errno(SYNTHETIC_ERRNO(EIO), "PE section header read error"); + + *ret = TAKE_PTR(sections); + *ret_n = scount; + return 0; + +no_sections: + *ret = NULL; + *ret_n = 0; + return 0; +} + +static int find_pe_section(struct PeSectionHeader *sections, size_t scount, + const uint8_t *name, size_t namelen, size_t *ret) { + for (size_t s = 0; s < scount; s++) { + if (memcmp_nn(sections[s].Name, sizeof(sections[s].Name), + name, namelen) == 0) { + if (ret) + *ret = s; + return 1; + } + } + return 0; +} + +static bool is_uki(struct PeSectionHeader *sections, size_t scount) { + return (find_pe_section(sections, scount, name_osrel, sizeof(name_osrel), NULL) && + find_pe_section(sections, scount, name_linux, sizeof(name_linux), NULL) && + find_pe_section(sections, scount, name_initrd, sizeof(name_initrd), NULL)); +} + +int verb_kernel_identify(int argc, char *argv[], void *userdata) { + _cleanup_fclose_ FILE *uki = NULL; + _cleanup_free_ struct PeSectionHeader *sections = NULL; + size_t scount; + int rc; + + uki = fopen(argv[1], "re"); + if (!uki) + return log_error_errno(errno, "Failed to open UKI file '%s': %m", argv[1]); + + rc = pe_sections(uki, §ions, &scount); + if (rc < 0) + return EXIT_FAILURE; + + if (sections) { + if (is_uki(sections, scount)) { + puts("uki"); + return EXIT_SUCCESS; + } + puts("pe"); + return EXIT_SUCCESS; + } + + puts("unknown"); + return EXIT_SUCCESS; +} |