bus: don't calculate kmsg message too large

[elogind.git] / src / shared / efivars.c

diff --git a/src/shared/efivars.c b/src/shared/efivars.c
index 3e59ee5e7de9435f6ebb91ef97e4ed0e7e51067b..8d004bad33525832237f942cadd9c435d2623691 100644 (file)
--- a/src/shared/efivars.c
+++ b/src/shared/efivars.c
@@ -22,15 +22,48 @@
 #include <unistd.h>
 #include <string.h>
 #include <fcntl.h>
+#include <ctype.h>
 
 #include "util.h"
 #include "utf8.h"
 #include "efivars.h"
 
+#ifdef ENABLE_EFI
+
 bool is_efi_boot(void) {
         return access("/sys/firmware/efi", F_OK) >= 0;
 }
 
+static int read_flag(const char *varname) {
+        int r;
+        void *v;
+        size_t s;
+        uint8_t b;
+
+        r = efi_get_variable(EFI_VENDOR_GLOBAL, varname, NULL, &v, &s);
+        if (r < 0)
+                return r;
+
+        if (s != 1) {
+                r = -EINVAL;
+                goto finish;
+        }
+
+        b = *(uint8_t *)v;
+        r = b > 0;
+finish:
+        free(v);
+        return r;
+}
+
+int is_efi_secure_boot(void) {
+        return read_flag("SecureBoot");
+}
+
+int is_efi_secure_boot_setup_mode(void) {
+        return read_flag("SetupMode");
+}
+
 int efi_get_variable(
                 sd_id128_t vendor,
                 const char *name,
@@ -78,7 +111,7 @@ int efi_get_variable(
         n = read(fd, r, (size_t) st.st_size - 4);
         if (n < 0) {
                 free(r);
-                return (int) -n;
+                return -errno;
         }
         if (n != (ssize_t) st.st_size - 4) {
                 free(r);
@@ -198,10 +231,12 @@ int efi_get_boot_option(
         if (title_size > l - offsetof(struct boot_option, title))
                 return -EINVAL;
 
-        s = utf16_to_utf8(header->title, title_size);
-        if (!s) {
-                err = -ENOMEM;
-                goto err;
+        if (title) {
+                s = utf16_to_utf8(header->title, title_size);
+                if (!s) {
+                        err = -ENOMEM;
+                        goto err;
+                }
         }
 
         if (header->path_len > 0) {
@@ -237,12 +272,13 @@ int efi_get_boot_option(
                                 if (dpath->drive.signature_type != 0x02)
                                         continue;
 
-                                efi_guid_to_id128(dpath->drive.signature, &p_uuid);
+                                if (part_uuid)
+                                        efi_guid_to_id128(dpath->drive.signature, &p_uuid);
                                 continue;
                         }
 
                         /* Sub-Type 4 – File Path */
-                        if (dpath->sub_type == 0x04) {
+                        if (dpath->sub_type == 0x04 && !p && path) {
                                 p = utf16_to_utf8(dpath->path, dpath->length-4);
                                 continue;
                         }
@@ -287,11 +323,32 @@ int efi_get_boot_order(uint16_t **order) {
         return (int) (l / sizeof(uint16_t));
 }
 
+static int boot_id_hex(const char s[4]) {
+        int i;
+        int id = 0;
+
+        for (i = 0; i < 4; i++)
+                if (s[i] >= '0' && s[i] <= '9')
+                        id |= (s[i] - '0') << (3 - i) * 4;
+                else if (s[i] >= 'A' && s[i] <= 'F')
+                        id |= (s[i] - 'A' + 10) << (3 - i) * 4;
+                else
+                        return -1;
+
+        return id;
+}
+
+static int cmp_uint16(const void *_a, const void *_b) {
+        const uint16_t *a = _a, *b = _b;
+
+        return (int)*a - (int)*b;
+}
+
 int efi_get_boot_options(uint16_t **options) {
         _cleanup_closedir_ DIR *dir = NULL;
         struct dirent *de;
         uint16_t *list = NULL;
-        int count = 0;
+        int count = 0, r;
 
         assert(options);
 
@@ -299,62 +356,55 @@ int efi_get_boot_options(uint16_t **options) {
         if (!dir)
                 return -errno;
 
-        while ((de = readdir(dir))) {
-                size_t n;
-                int a, b, c, d;
+        FOREACH_DIRENT(de, dir, r = -errno; goto fail) {
+                int id;
                 uint16_t *t;
 
                 if (strncmp(de->d_name, "Boot", 4) != 0)
                         continue;
 
-                n = strlen(de->d_name);
-                if (n != 45)
+                if (strlen(de->d_name) != 45)
                         continue;
 
                 if (strcmp(de->d_name + 8, "-8be4df61-93ca-11d2-aa0d-00e098032b8c") != 0)
                         continue;
 
-                a = de->d_name[4];
-                b = de->d_name[5];
-                c = de->d_name[6];
-                d = de->d_name[7];
-
-                if (!isdigit(a) || !isdigit(b) || !isdigit(c) || !isdigit(d))
+                id = boot_id_hex(de->d_name + 4);
+                if (id < 0)
                         continue;
 
                 t = realloc(list, (count + 1) * sizeof(uint16_t));
                 if (!t) {
-                        free(list);
-                        return -ENOMEM;
+                        r = -ENOMEM;
+                        goto fail;
                 }
 
                 list = t;
-                list[count ++] = (a - '0') * 1000 + (b - '0') * 100 + (c - '0') * 10 + (d - '0');
-
+                list[count ++] = id;
         }
 
+        qsort(list, count, sizeof(uint16_t), cmp_uint16);
+
         *options = list;
         return count;
+
+fail:
+        free(list);
+        return r;
 }
 
 static int read_usec(sd_id128_t vendor, const char *name, usec_t *u) {
-        _cleanup_free_ void *i = NULL;
         _cleanup_free_ char *j = NULL;
-        size_t is;
         int r;
         uint64_t x;
 
         assert(name);
         assert(u);
 
-        r = efi_get_variable(EFI_VENDOR_LOADER, name, NULL, &i, &is);
+        r = efi_get_variable_string(EFI_VENDOR_LOADER, name, &j);
         if (r < 0)
                 return r;
 
-        j = utf16_to_utf8(i, is);
-        if (!j)
-                return -ENOMEM;
-
         r = safe_atou64(j, &x);
         if (r < 0)
                 return r;
@@ -427,22 +477,16 @@ int efi_get_boot_timestamps(const dual_timestamp *n, dual_timestamp *firmware, d
 }
 
 int efi_get_loader_device_part_uuid(sd_id128_t *u) {
-        _cleanup_free_ void *s = NULL;
         _cleanup_free_ char *p = NULL;
-        size_t ss;
         int r, parsed[16];
         unsigned i;
 
         assert(u);
 
-        r = efi_get_variable(EFI_VENDOR_LOADER, "LoaderDevicePartUUID", NULL, &s, &ss);
+        r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderDevicePartUUID", &p);
         if (r < 0)
                 return r;
 
-        p = utf16_to_utf8(s, ss);
-        if (!p)
-                return -ENOMEM;
-
         if (sscanf(p, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                    &parsed[0], &parsed[1], &parsed[2], &parsed[3],
                    &parsed[4], &parsed[5], &parsed[6], &parsed[7],
@@ -455,3 +499,5 @@ int efi_get_loader_device_part_uuid(sd_id128_t *u) {
 
         return 0;
 }
+
+#endif