src/shared/util.[ch]: import functions from upstream for previous commits

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>

2 files changed, 480 insertions, 1 deletions

diff --git a/src/shared/util.c b/src/shared/util.c
index c30b4eaf57..f726e0ee2b 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -60,11 +60,12 @@
 #include "missing.h"
 #include "log.h"
 #include "strv.h"
-#include "label.h"
+#include "mkdir.h"
 #include "path-util.h"
 #include "exit-status.h"
 #include "hashmap.h"
 #include "fileio.h"
+#include "utf8.h"
 #include "virt.h"
 #include "process-util.h"
 #include "random-util.h"
@@ -511,10 +512,32 @@ char hexchar(int x) {
         return table[x & 15];
 }
 
+int unhexchar(char c) {
+
+        if (c >= '0' && c <= '9')
+                return c - '0';
+
+        if (c >= 'a' && c <= 'f')
+                return c - 'a' + 10;
+
+        if (c >= 'A' && c <= 'F')
+                return c - 'A' + 10;
+
+        return -EINVAL;
+}
+
 char octchar(int x) {
         return '0' + (x & 7);
 }
 
+int unoctchar(char c) {
+
+        if (c >= '0' && c <= '7')
+                return c - '0';
+
+        return -EINVAL;
+}
+
 char *cescape(const char *s) {
         char *r, *t;
         const char *f;
@@ -536,6 +559,208 @@ char *cescape(const char *s) {
         return r;
 }
 
+
+static int cunescape_one(const char *p, size_t length, char *ret, uint32_t *ret_unicode) {
+        int r = 1;
+
+        assert(p);
+        assert(*p);
+        assert(ret);
+
+        /* Unescapes C style. Returns the unescaped character in ret,
+         * unless we encountered a \u sequence in which case the full
+         * unicode character is returned in ret_unicode, instead. */
+
+        if (length != (size_t) -1 && length < 1)
+                return -EINVAL;
+
+        switch (p[0]) {
+
+        case 'a':
+                *ret = '\a';
+                break;
+        case 'b':
+                *ret = '\b';
+                break;
+        case 'f':
+                *ret = '\f';
+                break;
+        case 'n':
+                *ret = '\n';
+                break;
+        case 'r':
+                *ret = '\r';
+                break;
+        case 't':
+                *ret = '\t';
+                break;
+        case 'v':
+                *ret = '\v';
+                break;
+        case '\\':
+                *ret = '\\';
+                break;
+        case '"':
+                *ret = '"';
+                break;
+        case '\'':
+                *ret = '\'';
+                break;
+
+        case 's':
+                /* This is an extension of the XDG syntax files */
+                *ret = ' ';
+                break;
+
+        case 'x': {
+                /* hexadecimal encoding */
+                int a, b;
+
+                if (length != (size_t) -1 && length < 3)
+                        return -EINVAL;
+
+                a = unhexchar(p[1]);
+                if (a < 0)
+                        return -EINVAL;
+
+                b = unhexchar(p[2]);
+                if (b < 0)
+                        return -EINVAL;
+
+                /* Don't allow NUL bytes */
+                if (a == 0 && b == 0)
+                        return -EINVAL;
+
+                *ret = (char) ((a << 4U) | b);
+                r = 3;
+                break;
+        }
+
+        case 'u': {
+                /* C++11 style 16bit unicode */
+
+                int a[4];
+                unsigned i;
+                uint32_t c;
+
+                if (length != (size_t) -1 && length < 5)
+                        return -EINVAL;
+
+                for (i = 0; i < 4; i++) {
+                        a[i] = unhexchar(p[1 + i]);
+                        if (a[i] < 0)
+                                return a[i];
+                }
+
+                c = ((uint32_t) a[0] << 12U) | ((uint32_t) a[1] << 8U) | ((uint32_t) a[2] << 4U) | (uint32_t) a[3];
+
+                /* Don't allow 0 chars */
+                if (c == 0)
+                        return -EINVAL;
+
+                if (c < 128)
+                        *ret = c;
+                else {
+                        if (!ret_unicode)
+                                return -EINVAL;
+
+                        *ret = 0;
+                        *ret_unicode = c;
+                }
+
+                r = 5;
+                break;
+        }
+
+        case 'U': {
+                /* C++11 style 32bit unicode */
+
+                int a[8];
+                unsigned i;
+                uint32_t c;
+
+                if (length != (size_t) -1 && length < 9)
+                        return -EINVAL;
+
+                for (i = 0; i < 8; i++) {
+                        a[i] = unhexchar(p[1 + i]);
+                        if (a[i] < 0)
+                                return a[i];
+                }
+
+                c = ((uint32_t) a[0] << 28U) | ((uint32_t) a[1] << 24U) | ((uint32_t) a[2] << 20U) | ((uint32_t) a[3] << 16U) |
+                    ((uint32_t) a[4] << 12U) | ((uint32_t) a[5] <<  8U) | ((uint32_t) a[6] <<  4U) |  (uint32_t) a[7];
+
+                /* Don't allow 0 chars */
+                if (c == 0)
+                        return -EINVAL;
+
+                /* Don't allow invalid code points */
+                if (!unichar_is_valid(c))
+                        return -EINVAL;
+
+                if (c < 128)
+                        *ret = c;
+                else {
+                        if (!ret_unicode)
+                                return -EINVAL;
+
+                        *ret = 0;
+                        *ret_unicode = c;
+                }
+
+                r = 9;
+                break;
+        }
+
+        case '0':
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7': {
+                /* octal encoding */
+                int a, b, c;
+                uint32_t m;
+
+                if (length != (size_t) -1 && length < 4)
+                        return -EINVAL;
+
+                a = unoctchar(p[0]);
+                if (a < 0)
+                        return -EINVAL;
+
+                b = unoctchar(p[1]);
+                if (b < 0)
+                        return -EINVAL;
+
+                c = unoctchar(p[2]);
+                if (c < 0)
+                        return -EINVAL;
+
+                /* don't allow NUL bytes */
+                if (a == 0 && b == 0 && c == 0)
+                        return -EINVAL;
+
+                /* Don't allow bytes above 255 */
+                m = ((uint32_t) a << 6U) | ((uint32_t) b << 3U) | (uint32_t) c;
+                if (m > 255)
+                        return -EINVAL;
+
+                *ret = m;
+                r = 3;
+                break;
+        }
+
+        default:
+                return -EINVAL;
+        }
+
+        return r;
+}
+
 char *xescape(const char *s, const char *bad) {
         char *r, *t;
         const char *f;
@@ -1328,6 +1553,45 @@ int proc_cmdline(char **ret) {
                 return read_one_line_file("/proc/cmdline", ret);
 }
 
+int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) {
+        _cleanup_free_ char *line = NULL;
+        const char *p;
+        int r;
+
+        assert(parse_item);
+
+        r = proc_cmdline(&line);
+        if (r < 0)
+                return r;
+
+        p = line;
+        for (;;) {
+                _cleanup_free_ char *word = NULL;
+                char *value = NULL;
+
+                r = unquote_first_word(&p, &word, UNQUOTE_RELAX);
+                if (r < 0)
+                        return r;
+                if (r == 0)
+                        break;
+
+                /* Filter out arguments that are intended only for the
+                 * initrd */
+                if (!in_initrd() && startswith(word, "rd."))
+                        continue;
+
+                value = strchr(word, '=');
+                if (value)
+                        *(value++) = 0;
+
+                r = parse_item(word, value);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
 int getpeercred(int fd, struct ucred *ucred) {
         socklen_t n = sizeof(struct ucred);
         struct ucred u;
@@ -1433,6 +1697,211 @@ int is_dir(const char* path, bool follow) {
         return !!S_ISDIR(st.st_mode);
 }
 
+int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) {
+        _cleanup_free_ char *s = NULL;
+        size_t allocated = 0, sz = 0;
+        int r;
+
+        enum {
+                START,
+                VALUE,
+                VALUE_ESCAPE,
+                SINGLE_QUOTE,
+                SINGLE_QUOTE_ESCAPE,
+                DOUBLE_QUOTE,
+                DOUBLE_QUOTE_ESCAPE,
+                SPACE,
+        } state = START;
+
+        assert(p);
+        assert(*p);
+        assert(ret);
+
+        /* Parses the first word of a string, and returns it in
+         * *ret. Removes all quotes in the process. When parsing fails
+         * (because of an uneven number of quotes or similar), leaves
+         * the pointer *p at the first invalid character. */
+
+        for (;;) {
+                char c = **p;
+
+                switch (state) {
+
+                case START:
+                        if (c == 0)
+                                goto finish;
+                        else if (strchr(WHITESPACE, c))
+                                break;
+
+                        state = VALUE;
+                        /* fallthrough */
+
+                case VALUE:
+                        if (c == 0)
+                                goto finish;
+                        else if (c == '\'')
+                                state = SINGLE_QUOTE;
+                        else if (c == '\\')
+                                state = VALUE_ESCAPE;
+                        else if (c == '\"')
+                                state = DOUBLE_QUOTE;
+                        else if (strchr(WHITESPACE, c))
+                                state = SPACE;
+                        else {
+                                if (!GREEDY_REALLOC(s, allocated, sz+2))
+                                        return -ENOMEM;
+
+                                s[sz++] = c;
+                        }
+
+                        break;
+
+                case VALUE_ESCAPE:
+                        if (c == 0) {
+                                if (flags & UNQUOTE_RELAX)
+                                        goto finish;
+                                return -EINVAL;
+                        }
+
+                        if (!GREEDY_REALLOC(s, allocated, sz+7))
+                                return -ENOMEM;
+
+                        if (flags & UNQUOTE_CUNESCAPE) {
+                                uint32_t u;
+
+                                r = cunescape_one(*p, (size_t) -1, &c, &u);
+                                if (r < 0)
+                                        return -EINVAL;
+
+                                (*p) += r - 1;
+
+                                if (c != 0)
+                                        s[sz++] = c; /* normal explicit char */
+                                else
+                                        sz += utf8_encode_unichar(s + sz, u); /* unicode chars we'll encode as utf8 */
+                        } else
+                                s[sz++] = c;
+
+                        state = VALUE;
+                        break;
+
+                case SINGLE_QUOTE:
+                        if (c == 0) {
+                                if (flags & UNQUOTE_RELAX)
+                                        goto finish;
+                                return -EINVAL;
+                        } else if (c == '\'')
+                                state = VALUE;
+                        else if (c == '\\')
+                                state = SINGLE_QUOTE_ESCAPE;
+                        else {
+                                if (!GREEDY_REALLOC(s, allocated, sz+2))
+                                        return -ENOMEM;
+
+                                s[sz++] = c;
+                        }
+
+                        break;
+
+                case SINGLE_QUOTE_ESCAPE:
+                        if (c == 0) {
+                                if (flags & UNQUOTE_RELAX)
+                                        goto finish;
+                                return -EINVAL;
+                        }
+
+                        if (!GREEDY_REALLOC(s, allocated, sz+7))
+                                return -ENOMEM;
+
+                        if (flags & UNQUOTE_CUNESCAPE) {
+                                uint32_t u;
+
+                                r = cunescape_one(*p, (size_t) -1, &c, &u);
+                                if (r < 0)
+                                        return -EINVAL;
+
+                                (*p) += r - 1;
+
+                                if (c != 0)
+                                        s[sz++] = c;
+                                else
+                                        sz += utf8_encode_unichar(s + sz, u);
+                        } else
+                                s[sz++] = c;
+
+                        state = SINGLE_QUOTE;
+                        break;
+
+                case DOUBLE_QUOTE:
+                        if (c == 0)
+                                return -EINVAL;
+                        else if (c == '\"')
+                                state = VALUE;
+                        else if (c == '\\')
+                                state = DOUBLE_QUOTE_ESCAPE;
+                        else {
+                                if (!GREEDY_REALLOC(s, allocated, sz+2))
+                                        return -ENOMEM;
+
+                                s[sz++] = c;
+                        }
+
+                        break;
+
+                case DOUBLE_QUOTE_ESCAPE:
+                        if (c == 0) {
+                                if (flags & UNQUOTE_RELAX)
+                                        goto finish;
+                                return -EINVAL;
+                        }
+
+                        if (!GREEDY_REALLOC(s, allocated, sz+7))
+                                return -ENOMEM;
+
+                        if (flags & UNQUOTE_CUNESCAPE) {
+                                uint32_t u;
+
+                                r = cunescape_one(*p, (size_t) -1, &c, &u);
+                                if (r < 0)
+                                        return -EINVAL;
+
+                                (*p) += r - 1;
+
+                                if (c != 0)
+                                        s[sz++] = c;
+                                else
+                                        sz += utf8_encode_unichar(s + sz, u);
+                        } else
+                                s[sz++] = c;
+
+                        state = DOUBLE_QUOTE;
+                        break;
+
+                case SPACE:
+                        if (c == 0)
+                                goto finish;
+                        if (!strchr(WHITESPACE, c))
+                                goto finish;
+
+                        break;
+                }
+
+                (*p) ++;
+        }
+
+finish:
+        if (!s) {
+                *ret = NULL;
+                return 0;
+        }
+
+        s[sz] = 0;
+        *ret = s;
+        s = NULL;
+
+        return 1;
+}
+
 int execute_command(const char *command, char *const argv[]) {
 
         pid_t pid;
diff --git a/src/shared/util.h b/src/shared/util.h
index 2aa8da0989..f6c8f75649 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -140,7 +140,9 @@ char *truncate_nl(char *s);
 int rmdir_parents(const char *path, const char *stop);
 
 char hexchar(int x) _const_;
+int unhexchar(char c) _const_;
 char octchar(int x) _const_;
+int unoctchar(char c) _const_;
 
 char *cescape(const char *s);
 size_t cescape_char(char c, char *buf);
@@ -390,6 +392,7 @@ static inline void qsort_safe(void *base, size_t nmemb, size_t size,
 }
 
 int proc_cmdline(char **ret);
+int parse_proc_cmdline(int (*parse_word)(const char *key, const char *value));
 int getpeercred(int fd, struct ucred *ucred);
 
 #if HAVE_DECL_MKOSTEMP
@@ -408,6 +411,13 @@ int tempfn_xxxxxx(const char *p, char **ret);
 
 int is_dir(const char *path, bool follow);
 
+typedef enum UnquoteFlags {
+        UNQUOTE_RELAX     = 1,
+        UNQUOTE_CUNESCAPE = 2,
+} UnquoteFlags;
+
+int unquote_first_word(const char **p, char **ret, UnquoteFlags flags);
+
 int execute_command(const char *command, char *const argv[]);
 
 #define INOTIFY_EVENT_MAX (sizeof(struct inotify_event) + NAME_MAX + 1)