chiark / gitweb /
fileio: quote more shell characters in envfiles
[elogind.git] / src / shared / fileio.c
index 77fd05955a54b4286f4a845025d462d4fbca716f..cbb40c237998438fac7ef27234bcb134866c44dc 100644 (file)
 ***/
 
 #include <unistd.h>
+#include <sys/sendfile.h>
 #include "fileio.h"
 #include "util.h"
 #include "strv.h"
 #include "utf8.h"
+#include "ctype.h"
+
+int write_string_stream(FILE *f, const char *line) {
+        assert(f);
+        assert(line);
 
-int write_string_to_file(FILE *f, const char *line) {
         errno = 0;
+
         fputs(line, f);
         if (!endswith(line, "\n"))
                 fputc('\n', f);
@@ -49,7 +55,7 @@ int write_string_file(const char *fn, const char *line) {
         if (!f)
                 return -errno;
 
-        return write_string_to_file(f, line);
+        return write_string_stream(f, line);
 }
 
 int write_string_file_atomic(const char *fn, const char *line) {
@@ -116,22 +122,37 @@ int read_one_line_file(const char *fn, char **line) {
         return 0;
 }
 
-int read_full_file(const char *fn, char **contents, size_t *size) {
-        _cleanup_fclose_ FILE *f = NULL;
+ssize_t sendfile_full(int out_fd, const char *fn) {
+        _cleanup_fclose_ FILE *f;
+        struct stat st;
+        int r;
+        ssize_t s;
+
         size_t n, l;
         _cleanup_free_ char *buf = NULL;
-        struct stat st;
 
+        assert(out_fd > 0);
         assert(fn);
-        assert(contents);
 
         f = fopen(fn, "re");
         if (!f)
                 return -errno;
 
-        if (fstat(fileno(f), &st) < 0)
+        r = fstat(fileno(f), &st);
+        if (r < 0)
                 return -errno;
 
+        s = sendfile(out_fd, fileno(f), NULL, st.st_size);
+        if (s < 0)
+                if (errno == EINVAL || errno == ENOSYS) {
+                        /* continue below */
+                } else
+                        return -errno;
+        else
+                return s;
+
+        /* sendfile() failed, fall back to read/write */
+
         /* Safety check */
         if (st.st_size > 4*1024*1024)
                 return -E2BIG;
@@ -139,6 +160,66 @@ int read_full_file(const char *fn, char **contents, size_t *size) {
         n = st.st_size > 0 ? st.st_size : LINE_MAX;
         l = 0;
 
+        while (true) {
+                char *t;
+                size_t k;
+
+                t = realloc(buf, n);
+                if (!t)
+                        return -ENOMEM;
+
+                buf = t;
+                k = fread(buf + l, 1, n - l, f);
+
+                if (k <= 0) {
+                        if (ferror(f))
+                                return -errno;
+
+                        break;
+                }
+
+                l += k;
+                n *= 2;
+
+                /* Safety check */
+                if (n > 4*1024*1024)
+                        return -E2BIG;
+        }
+
+        r = write(out_fd, buf, l);
+        if (r < 0)
+                return -errno;
+
+        return (ssize_t) l;
+}
+
+int read_full_stream(FILE *f, char **contents, size_t *size) {
+        size_t n, l;
+        _cleanup_free_ char *buf = NULL;
+        struct stat st;
+
+        assert(f);
+        assert(contents);
+
+        if (fstat(fileno(f), &st) < 0)
+                return -errno;
+
+        n = LINE_MAX;
+
+        if (S_ISREG(st.st_mode)) {
+
+                /* Safety check */
+                if (st.st_size > 4*1024*1024)
+                        return -E2BIG;
+
+                /* Start with the right file size, but be prepared for
+                 * files from /proc which generally report a file size
+                 * of 0 */
+                if (st.st_size > 0)
+                        n = st.st_size;
+        }
+
+        l = 0;
         for (;;) {
                 char *t;
                 size_t k;
@@ -167,7 +248,7 @@ int read_full_file(const char *fn, char **contents, size_t *size) {
 
         buf[l] = 0;
         *contents = buf;
-        buf = NULL;
+        buf = NULL; /* do not free */
 
         if (size)
                 *size = l;
@@ -175,7 +256,21 @@ int read_full_file(const char *fn, char **contents, size_t *size) {
         return 0;
 }
 
+int read_full_file(const char *fn, char **contents, size_t *size) {
+        _cleanup_fclose_ FILE *f = NULL;
+
+        assert(fn);
+        assert(contents);
+
+        f = fopen(fn, "re");
+        if (!f)
+                return -errno;
+
+        return read_full_stream(f, contents, size);
+}
+
 static int parse_env_file_internal(
+                FILE *f,
                 const char *fname,
                 const char *newline,
                 int (*push) (const char *filename, unsigned line,
@@ -202,10 +297,12 @@ static int parse_env_file_internal(
                 COMMENT_ESCAPE
         } state = PRE_KEY;
 
-        assert(fname);
         assert(newline);
 
-        r = read_full_file(fname, &contents, NULL);
+        if (f)
+                r = read_full_stream(f, &contents, NULL);
+        else
+                r = read_full_file(fname, &contents, NULL);
         if (r < 0)
                 return r;
 
@@ -221,7 +318,7 @@ static int parse_env_file_internal(
                                 state = KEY;
                                 last_key_whitespace = (size_t) -1;
 
-                                if (!greedy_realloc((void**) &key, &key_alloc, n_key+2)) {
+                                if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -244,7 +341,7 @@ static int parse_env_file_internal(
                                 else if (last_key_whitespace == (size_t) -1)
                                          last_key_whitespace = n_key;
 
-                                if (!greedy_realloc((void**) &key, &key_alloc, n_key+2)) {
+                                if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -284,7 +381,7 @@ static int parse_env_file_internal(
                         else if (!strchr(WHITESPACE, c)) {
                                 state = VALUE;
 
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -329,7 +426,7 @@ static int parse_env_file_internal(
                                 else if (last_value_whitespace == (size_t) -1)
                                         last_value_whitespace = n_value;
 
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -344,7 +441,7 @@ static int parse_env_file_internal(
 
                         if (!strchr(newline, c)) {
                                 /* Escaped newlines we eat up entirely */
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -359,7 +456,7 @@ static int parse_env_file_internal(
                         else if (c == '\\')
                                 state = SINGLE_QUOTE_VALUE_ESCAPE;
                         else {
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -373,7 +470,7 @@ static int parse_env_file_internal(
                         state = SINGLE_QUOTE_VALUE;
 
                         if (!strchr(newline, c)) {
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -388,7 +485,7 @@ static int parse_env_file_internal(
                         else if (c == '\\')
                                 state = DOUBLE_QUOTE_VALUE_ESCAPE;
                         else {
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -402,7 +499,7 @@ static int parse_env_file_internal(
                         state = DOUBLE_QUOTE_VALUE;
 
                         if (!strchr(newline, c)) {
-                                if (!greedy_realloc((void**) &value, &value_alloc, n_value+2)) {
+                                if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
@@ -459,38 +556,48 @@ fail:
         return r;
 }
 
-static int parse_env_file_push(const char *filename, unsigned line,
-                               const char *key, char *value, void *userdata) {
-        assert(utf8_is_valid(key));
+static int parse_env_file_push(
+                const char *filename, unsigned line,
+                const char *key, char *value,
+                void *userdata) {
 
-        if (value && !utf8_is_valid(value))
-                /* FIXME: filter UTF-8 */
-                log_error("%s:%u: invalid UTF-8 for key %s: '%s', ignoring.",
-                          filename, line, key, value);
-        else {
-                const char *k;
-                va_list* ap = (va_list*) userdata;
-                va_list aq;
+        const char *k;
+        va_list aq, *ap = userdata;
 
-                va_copy(aq, *ap);
+        if (!utf8_is_valid(key)) {
+                _cleanup_free_ char *p;
 
-                while ((k = va_arg(aq, const char *))) {
-                        char **v;
+                p = utf8_escape_invalid(key);
+                log_error("%s:%u: invalid UTF-8 in key '%s', ignoring.", strna(filename), line, p);
+                return -EINVAL;
+        }
 
-                        v = va_arg(aq, char **);
+        if (value && !utf8_is_valid(value)) {
+                _cleanup_free_ char *p;
 
-                        if (streq(key, k)) {
-                                va_end(aq);
-                                free(*v);
-                                *v = value;
-                                return 1;
-                        }
-                }
+                p = utf8_escape_invalid(value);
+                log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, p);
+                return -EINVAL;
+        }
+
+        va_copy(aq, *ap);
+
+        while ((k = va_arg(aq, const char *))) {
+                char **v;
+
+                v = va_arg(aq, char **);
 
-                va_end(aq);
+                if (streq(key, k)) {
+                        va_end(aq);
+                        free(*v);
+                        *v = value;
+                        return 1;
+                }
         }
 
+        va_end(aq);
         free(value);
+
         return 0;
 }
 
@@ -505,48 +612,109 @@ int parse_env_file(
                 newline = NEWLINE;
 
         va_start(ap, newline);
-        r = parse_env_file_internal(fname, newline, parse_env_file_push, &ap);
+        r = parse_env_file_internal(NULL, fname, newline, parse_env_file_push, &ap);
         va_end(ap);
 
         return r;
 }
 
-static int load_env_file_push(const char *filename, unsigned line,
-                              const char *key, char *value, void *userdata) {
-        assert(utf8_is_valid(key));
+static int load_env_file_push(
+                const char *filename, unsigned line,
+                const char *key, char *value,
+                void *userdata) {
+        char ***m = userdata;
+        char *p;
+        int r;
 
-        if (value && !utf8_is_valid(value))
-                /* FIXME: filter UTF-8 */
-                log_error("%s:%u: invalid UTF-8 for key %s: '%s', ignoring.",
-                          filename, line, key, value);
-        else {
-                char ***m = userdata;
-                char *p;
-                int r;
+        if (!utf8_is_valid(key)) {
+                _cleanup_free_ char *t = utf8_escape_invalid(key);
 
-                p = strjoin(key, "=", strempty(value), NULL);
-                if (!p)
-                        return -ENOMEM;
+                log_error("%s:%u: invalid UTF-8 for key '%s', ignoring.", strna(filename), line, t);
+                return -EINVAL;
+        }
 
-                r = strv_push(m, p);
-                if (r < 0) {
-                        free(p);
-                        return r;
-                }
+        if (value && !utf8_is_valid(value)) {
+                _cleanup_free_ char *t = utf8_escape_invalid(value);
+
+                log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, t);
+                return -EINVAL;
         }
 
+        p = strjoin(key, "=", strempty(value), NULL);
+        if (!p)
+                return -ENOMEM;
+
+        r = strv_consume(m, p);
+        if (r < 0)
+                return r;
+
         free(value);
         return 0;
 }
 
-int load_env_file(const char *fname, const char *newline, char ***rl) {
+int load_env_file(FILE *f, const char *fname, const char *newline, char ***rl) {
+        char **m = NULL;
+        int r;
+
+        if (!newline)
+                newline = NEWLINE;
+
+        r = parse_env_file_internal(f, fname, newline, load_env_file_push, &m);
+        if (r < 0) {
+                strv_free(m);
+                return r;
+        }
+
+        *rl = m;
+        return 0;
+}
+
+static int load_env_file_push_pairs(
+                const char *filename, unsigned line,
+                const char *key, char *value,
+                void *userdata) {
+        char ***m = userdata;
+        int r;
+
+        if (!utf8_is_valid(key)) {
+                _cleanup_free_ char *t = utf8_escape_invalid(key);
+
+                log_error("%s:%u: invalid UTF-8 for key '%s', ignoring.", strna(filename), line, t);
+                return -EINVAL;
+        }
+
+        if (value && !utf8_is_valid(value)) {
+                _cleanup_free_ char *t = utf8_escape_invalid(value);
+
+                log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, t);
+                return -EINVAL;
+        }
+
+        r = strv_extend(m, key);
+        if (r < 0)
+                return -ENOMEM;
+
+        if (!value) {
+                r = strv_extend(m, "");
+                if (r < 0)
+                        return -ENOMEM;
+        } else {
+                r = strv_push(m, value);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+int load_env_file_pairs(FILE *f, const char *fname, const char *newline, char ***rl) {
         char **m = NULL;
         int r;
 
         if (!newline)
                 newline = NEWLINE;
 
-        r = parse_env_file_internal(fname, newline, load_env_file_push, &m);
+        r = parse_env_file_internal(f, fname, newline, load_env_file_push_pairs, &m);
         if (r < 0) {
                 strv_free(m);
                 return r;
@@ -570,11 +738,11 @@ static void write_env_var(FILE *f, const char *v) {
         p++;
         fwrite(v, 1, p-v, f);
 
-        if (string_has_cc(p) || chars_intersect(p, WHITESPACE "\'\"\\`$")) {
+        if (string_has_cc(p, NULL) || chars_intersect(p, WHITESPACE SHELL_NEED_QUOTES)) {
                 fputc('\"', f);
 
                 for (; *p; p++) {
-                        if (strchr("\'\"\\`$", *p))
+                        if (strchr(SHELL_NEED_ESCAPE, *p))
                                 fputc('\\', f);
 
                         fputc(*p, f);
@@ -588,41 +756,37 @@ static void write_env_var(FILE *f, const char *v) {
 }
 
 int write_env_file(const char *fname, char **l) {
-        char **i;
-        _cleanup_free_ char *p = NULL;
         _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_free_ char *p = NULL;
+        char **i;
         int r;
 
+        assert(fname);
+
         r = fopen_temporary(fname, &f, &p);
         if (r < 0)
                 return r;
 
         fchmod_umask(fileno(f), 0644);
 
-        errno = 0;
         STRV_FOREACH(i, l)
                 write_env_var(f, *i);
 
-        fflush(f);
+        r = fflush_and_check(f);
+        if (r >= 0) {
+                if (rename(p, fname) >= 0)
+                        return 0;
 
-        if (ferror(f))
-                r = errno ? -errno : -EIO;
-        else {
-                if (rename(p, fname) < 0)
-                        r = -errno;
-                else
-                        r = 0;
+                r = -errno;
         }
 
-        if (r < 0)
-                unlink(p);
-
+        unlink(p);
         return r;
 }
 
 int executable_is_script(const char *path, char **interpreter) {
         int r;
-        char _cleanup_free_ *line = NULL;
+        _cleanup_free_ char *line = NULL;
         int len;
         char *ans;
 
@@ -648,3 +812,51 @@ int executable_is_script(const char *path, char **interpreter) {
         *interpreter = ans;
         return 1;
 }
+
+/**
+ * Retrieve one field from a file like /proc/self/status.  pattern
+ * should start with '\n' and end with a ':'. Whitespace and zeros
+ * after the ':' will be skipped. field must be freed afterwards.
+ */
+int get_status_field(const char *filename, const char *pattern, char **field) {
+        _cleanup_free_ char *status = NULL;
+        char *t;
+        size_t len;
+        int r;
+
+        assert(filename);
+        assert(pattern);
+        assert(field);
+
+        r = read_full_file(filename, &status, NULL);
+        if (r < 0)
+                return r;
+
+        t = strstr(status, pattern);
+        if (!t)
+                return -ENOENT;
+
+        t += strlen(pattern);
+        if (*t) {
+                t += strspn(t, " \t");
+
+                /* Also skip zeros, because when this is used for
+                 * capabilities, we don't want the zeros. This way the
+                 * same capability set always maps to the same string,
+                 * irrespective of the total capability set size. For
+                 * other numbers it shouldn't matter. */
+                t += strspn(t, "0");
+                /* Back off one char if there's nothing but whitespace
+                   and zeros */
+                if (!*t || isspace(*t))
+                        t --;
+        }
+
+        len = strcspn(t, WHITESPACE);
+
+        *field = strndup(t, len);
+        if (!*field)
+                return -ENOMEM;
+
+        return 0;
+}