Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 501 insertions, 0 deletions

diff --git a/src/basic/proc-cmdline.c b/src/basic/proc-cmdline.c
new file mode 100644
index 0000000..522d8de
--- /dev/null
+++ b/src/basic/proc-cmdline.c
@@ -0,0 +1,501 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <stdbool.h>
+#include <stddef.h>
+
+#include "alloc-util.h"
+#include "efivars.h"
+#include "extract-word.h"
+#include "fileio.h"
+#include "getopt-defs.h"
+#include "initrd-util.h"
+#include "macro.h"
+#include "parse-util.h"
+#include "proc-cmdline.h"
+#include "process-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "virt.h"
+
+int proc_cmdline_filter_pid1_args(char **argv, char ***ret) {
+        enum {
+                COMMON_GETOPT_ARGS,
+                SYSTEMD_GETOPT_ARGS,
+                SHUTDOWN_GETOPT_ARGS,
+        };
+        static const struct option options[] = {
+                COMMON_GETOPT_OPTIONS,
+                SYSTEMD_GETOPT_OPTIONS,
+                SHUTDOWN_GETOPT_OPTIONS,
+        };
+        static const char *short_options = SYSTEMD_GETOPT_SHORT_OPTIONS;
+
+        _cleanup_strv_free_ char **filtered = NULL;
+        int state, r;
+
+        assert(argv);
+        assert(ret);
+
+        /* Currently, we do not support '-', '+', and ':' at the beginning. */
+        assert(!IN_SET(short_options[0], '-', '+', ':'));
+
+        /* Filter out all known options. */
+        state = no_argument;
+        STRV_FOREACH(p, strv_skip(argv, 1)) {
+                int prev_state = state;
+                const char *a = *p;
+
+                /* Reset the state for the next step. */
+                state = no_argument;
+
+                if (prev_state == required_argument ||
+                    (prev_state == optional_argument && a[0] != '-'))
+                        /* Handled as an argument of the previous option, filtering out the string. */
+                        continue;
+
+                if (a[0] != '-') {
+                        /* Not an option, accepting the string. */
+                        r = strv_extend(&filtered, a);
+                        if (r < 0)
+                                return r;
+                        continue;
+                }
+
+                if (a[1] == '-') {
+                        if (a[2] == '\0') {
+                                /* "--" is specified, accepting remaining strings. */
+                                r = strv_extend_strv(&filtered, strv_skip(p, 1), /* filter_duplicates = */ false);
+                                if (r < 0)
+                                        return r;
+                                break;
+                        }
+
+                        /* long option, e.g. --foo */
+                        for (size_t i = 0; i < ELEMENTSOF(options); i++) {
+                                const char *q = startswith(a + 2, options[i].name);
+                                if (!q || !IN_SET(q[0], '=', '\0'))
+                                        continue;
+
+                                /* Found matching option, updating the state if necessary. */
+                                if (q[0] == '\0' && options[i].has_arg == required_argument)
+                                        state = required_argument;
+
+                                break;
+                        }
+                        continue;
+                }
+
+                /* short option(s), e.g. -x or -xyz */
+                while (a && *++a != '\0')
+                        for (const char *q = short_options; *q != '\0'; q++) {
+                                if (*q != *a)
+                                        continue;
+
+                                /* Found matching short option. */
+
+                                if (q[1] == ':') {
+                                        /* An argument is required or optional, and remaining part
+                                         * is handled as argument if exists. */
+                                        state = a[1] != '\0' ? no_argument :
+                                                q[2] == ':' ? optional_argument : required_argument;
+
+                                        a = NULL; /* Not necessary to parse remaining part. */
+                                }
+                                break;
+                        }
+        }
+
+        *ret = TAKE_PTR(filtered);
+        return 0;
+}
+
+int proc_cmdline(char **ret) {
+        const char *e;
+
+        assert(ret);
+
+        /* For testing purposes it is sometimes useful to be able to override what we consider /proc/cmdline to be */
+        e = secure_getenv("SYSTEMD_PROC_CMDLINE");
+        if (e) {
+                char *m;
+
+                m = strdup(e);
+                if (!m)
+                        return -ENOMEM;
+
+                *ret = m;
+                return 0;
+        }
+
+        if (detect_container() > 0)
+                return pid_get_cmdline(1, SIZE_MAX, 0, ret);
+
+        return read_virtual_file("/proc/cmdline", SIZE_MAX, ret, NULL);
+}
+
+static int proc_cmdline_strv_internal(char ***ret, bool filter_pid1_args) {
+        const char *e;
+        int r;
+
+        assert(ret);
+
+        /* For testing purposes it is sometimes useful to be able to override what we consider /proc/cmdline to be */
+        e = secure_getenv("SYSTEMD_PROC_CMDLINE");
+        if (e)
+                return strv_split_full(ret, e, NULL, EXTRACT_UNQUOTE|EXTRACT_RELAX|EXTRACT_RETAIN_ESCAPE);
+
+        if (detect_container() > 0) {
+                _cleanup_strv_free_ char **args = NULL;
+
+                r = pid_get_cmdline_strv(1, /* flags = */ 0, &args);
+                if (r < 0)
+                        return r;
+
+                if (filter_pid1_args)
+                        return proc_cmdline_filter_pid1_args(args, ret);
+
+                *ret = TAKE_PTR(args);
+                return 0;
+
+        } else {
+                _cleanup_free_ char *s = NULL;
+
+                r = read_full_file("/proc/cmdline", &s, NULL);
+                if (r < 0)
+                        return r;
+
+                return strv_split_full(ret, s, NULL, EXTRACT_UNQUOTE|EXTRACT_RELAX|EXTRACT_RETAIN_ESCAPE);
+        }
+}
+
+int proc_cmdline_strv(char ***ret) {
+        return proc_cmdline_strv_internal(ret, /* filter_pid1_args = */ false);
+}
+
+static char *mangle_word(const char *word, ProcCmdlineFlags flags) {
+        char *c;
+
+        c = startswith(word, "rd.");
+        if (c) {
+                /* Filter out arguments that are intended only for the initrd */
+
+                if (!in_initrd())
+                        return NULL;
+
+                if (FLAGS_SET(flags, PROC_CMDLINE_STRIP_RD_PREFIX))
+                        return c;
+
+        } else if (FLAGS_SET(flags, PROC_CMDLINE_RD_STRICT) && in_initrd())
+                /* And optionally filter out arguments that are intended only for the host */
+                return NULL;
+
+        return (char*) word;
+}
+
+static int proc_cmdline_parse_strv(char **args, proc_cmdline_parse_t parse_item, void *data, ProcCmdlineFlags flags) {
+        int r;
+
+        assert(parse_item);
+
+        STRV_FOREACH(word, args) {
+                char *key, *value;
+
+                key = mangle_word(*word, flags);
+                if (!key)
+                        continue;
+
+                value = strchr(key, '=');
+                if (value)
+                        *(value++) = '\0';
+
+                r = parse_item(key, value, data);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+int proc_cmdline_parse(proc_cmdline_parse_t parse_item, void *data, ProcCmdlineFlags flags) {
+        _cleanup_strv_free_ char **args = NULL;
+        int r;
+
+        assert(parse_item);
+
+        /* The PROC_CMDLINE_VALUE_OPTIONAL and PROC_CMDLINE_TRUE_WHEN_MISSING flags don't really make sense
+         * for proc_cmdline_parse(), let's make this clear. */
+        assert(!(flags & (PROC_CMDLINE_VALUE_OPTIONAL|PROC_CMDLINE_TRUE_WHEN_MISSING)));
+
+        /* We parse the EFI variable first, because later settings have higher priority. */
+
+        if (!FLAGS_SET(flags, PROC_CMDLINE_IGNORE_EFI_OPTIONS)) {
+                _cleanup_free_ char *line = NULL;
+
+                r = systemd_efi_options_variable(&line);
+                if (r < 0) {
+                        if (r != -ENODATA)
+                                log_debug_errno(r, "Failed to get SystemdOptions EFI variable, ignoring: %m");
+                } else {
+                        r = strv_split_full(&args, line, NULL, EXTRACT_UNQUOTE|EXTRACT_RELAX|EXTRACT_RETAIN_ESCAPE);
+                        if (r < 0)
+                                return r;
+
+                        r = proc_cmdline_parse_strv(args, parse_item, data, flags);
+                        if (r < 0)
+                                return r;
+
+                        args = strv_free(args);
+                }
+        }
+
+        r = proc_cmdline_strv_internal(&args, /* filter_pid1_args = */ true);
+        if (r < 0)
+                return r;
+
+        return proc_cmdline_parse_strv(args, parse_item, data, flags);
+}
+
+static bool relaxed_equal_char(char a, char b) {
+        return a == b ||
+                (a == '_' && b == '-') ||
+                (a == '-' && b == '_');
+}
+
+char *proc_cmdline_key_startswith(const char *s, const char *prefix) {
+        assert(s);
+        assert(prefix);
+
+        /* Much like startswith(), but considers "-" and "_" the same */
+
+        for (; *prefix != 0; s++, prefix++)
+                if (!relaxed_equal_char(*s, *prefix))
+                        return NULL;
+
+        return (char*) s;
+}
+
+bool proc_cmdline_key_streq(const char *x, const char *y) {
+        assert(x);
+        assert(y);
+
+        /* Much like streq(), but considers "-" and "_" the same */
+
+        for (; *x != 0 || *y != 0; x++, y++)
+                if (!relaxed_equal_char(*x, *y))
+                        return false;
+
+        return true;
+}
+
+static int cmdline_get_key(char **args, const char *key, ProcCmdlineFlags flags, char **ret_value) {
+        _cleanup_free_ char *v = NULL;
+        bool found = false;
+        int r;
+
+        assert(key);
+
+        STRV_FOREACH(p, args) {
+                const char *word;
+
+                word = mangle_word(*p, flags);
+                if (!word)
+                        continue;
+
+                if (ret_value) {
+                        const char *e;
+
+                        e = proc_cmdline_key_startswith(word, key);
+                        if (!e)
+                                continue;
+
+                        if (*e == '=') {
+                                r = free_and_strdup(&v, e+1);
+                                if (r < 0)
+                                        return r;
+
+                                found = true;
+
+                        } else if (*e == 0 && FLAGS_SET(flags, PROC_CMDLINE_VALUE_OPTIONAL))
+                                found = true;
+
+                } else {
+                        if (proc_cmdline_key_streq(word, key)) {
+                                found = true;
+                                break; /* we found what we were looking for */
+                        }
+                }
+        }
+
+        if (ret_value)
+                *ret_value = TAKE_PTR(v);
+
+        return found;
+}
+
+int proc_cmdline_get_key(const char *key, ProcCmdlineFlags flags, char **ret_value) {
+        _cleanup_strv_free_ char **args = NULL;
+        _cleanup_free_ char *line = NULL, *v = NULL;
+        int r;
+
+        /* Looks for a specific key on the kernel command line and (with lower priority) the EFI variable.
+         * Supports three modes:
+         *
+         * a) The "ret_value" parameter is used. In this case a parameter beginning with the "key" string followed by
+         *    "=" is searched for, and the value following it is returned in "ret_value".
+         *
+         * b) as above, but the PROC_CMDLINE_VALUE_OPTIONAL flag is set. In this case if the key is found as a separate
+         *    word (i.e. not followed by "=" but instead by whitespace or the end of the command line), then this is
+         *    also accepted, and "value" is returned as NULL.
+         *
+         * c) The "ret_value" parameter is NULL. In this case a search for the exact "key" parameter is performed.
+         *
+         * In all three cases, > 0 is returned if the key is found, 0 if not. */
+
+        /* PROC_CMDLINE_TRUE_WHEN_MISSING doesn't really make sense for proc_cmdline_get_key(). */
+        assert(!FLAGS_SET(flags, PROC_CMDLINE_TRUE_WHEN_MISSING));
+
+        if (isempty(key))
+                return -EINVAL;
+
+        if (FLAGS_SET(flags, PROC_CMDLINE_VALUE_OPTIONAL) && !ret_value)
+                return -EINVAL;
+
+        r = proc_cmdline_strv_internal(&args, /* filter_pid1_args = */ true);
+        if (r < 0)
+                return r;
+
+        if (FLAGS_SET(flags, PROC_CMDLINE_IGNORE_EFI_OPTIONS)) /* Shortcut */
+                return cmdline_get_key(args, key, flags, ret_value);
+
+        r = cmdline_get_key(args, key, flags, ret_value ? &v : NULL);
+        if (r < 0)
+                return r;
+        if (r > 0) {
+                if (ret_value)
+                        *ret_value = TAKE_PTR(v);
+
+                return r;
+        }
+
+        r = systemd_efi_options_variable(&line);
+        if (r == -ENODATA) {
+                if (ret_value)
+                        *ret_value = NULL;
+
+                return false; /* Not found */
+        }
+        if (r < 0)
+                return r;
+
+        args = strv_free(args);
+        r = strv_split_full(&args, line, NULL, EXTRACT_UNQUOTE|EXTRACT_RELAX|EXTRACT_RETAIN_ESCAPE);
+        if (r < 0)
+                return r;
+
+        return cmdline_get_key(args, key, flags, ret_value);
+}
+
+int proc_cmdline_get_bool(const char *key, ProcCmdlineFlags flags, bool *ret) {
+        _cleanup_free_ char *v = NULL;
+        int r;
+
+        assert(ret);
+
+        r = proc_cmdline_get_key(key, (flags & ~PROC_CMDLINE_TRUE_WHEN_MISSING) | PROC_CMDLINE_VALUE_OPTIONAL, &v);
+        if (r < 0)
+                return r;
+        if (r == 0) { /* key not specified at all */
+                *ret = FLAGS_SET(flags, PROC_CMDLINE_TRUE_WHEN_MISSING);
+                return 0;
+        }
+
+        if (v) { /* key with parameter passed */
+                r = parse_boolean(v);
+                if (r < 0)
+                        return r;
+                *ret = r;
+        } else /* key without parameter passed */
+                *ret = true;
+
+        return 1;
+}
+
+static int cmdline_get_key_ap(ProcCmdlineFlags flags, char* const* args, va_list ap) {
+        int r, ret = 0;
+
+        for (;;) {
+                char **v;
+                const char *k, *e;
+
+                k = va_arg(ap, const char*);
+                if (!k)
+                        break;
+
+                assert_se(v = va_arg(ap, char**));
+
+                STRV_FOREACH(p, args) {
+                        const char *word;
+
+                        word = mangle_word(*p, flags);
+                        if (!word)
+                                continue;
+
+                        e = proc_cmdline_key_startswith(word, k);
+                        if (e && *e == '=') {
+                                r = free_and_strdup(v, e + 1);
+                                if (r < 0)
+                                        return r;
+
+                                ret++;
+                        }
+                }
+        }
+
+        return ret;
+}
+
+int proc_cmdline_get_key_many_internal(ProcCmdlineFlags flags, ...) {
+        _cleanup_strv_free_ char **args = NULL;
+        int r, ret = 0;
+        va_list ap;
+
+        /* The PROC_CMDLINE_VALUE_OPTIONAL and PROC_CMDLINE_TRUE_WHEN_MISSING flags don't really make sense
+         * for proc_cmdline_get_key_many, let's make this clear. */
+        assert(!(flags & (PROC_CMDLINE_VALUE_OPTIONAL|PROC_CMDLINE_TRUE_WHEN_MISSING)));
+
+        /* This call may clobber arguments on failure! */
+
+        if (!FLAGS_SET(flags, PROC_CMDLINE_IGNORE_EFI_OPTIONS)) {
+                _cleanup_free_ char *line = NULL;
+
+                r = systemd_efi_options_variable(&line);
+                if (r < 0 && r != -ENODATA)
+                        log_debug_errno(r, "Failed to get SystemdOptions EFI variable, ignoring: %m");
+                if (r >= 0) {
+                        r = strv_split_full(&args, line, NULL, EXTRACT_UNQUOTE|EXTRACT_RELAX|EXTRACT_RETAIN_ESCAPE);
+                        if (r < 0)
+                                return r;
+
+                        va_start(ap, flags);
+                        r = cmdline_get_key_ap(flags, args, ap);
+                        va_end(ap);
+                        if (r < 0)
+                                return r;
+
+                        ret = r;
+                        args = strv_free(args);
+                }
+        }
+
+        r = proc_cmdline_strv(&args);
+        if (r < 0)
+                return r;
+
+        va_start(ap, flags);
+        r = cmdline_get_key_ap(flags, args, ap);
+        va_end(ap);
+        if (r < 0)
+                return r;
+
+        return ret + r;
+}