/*
* Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
+ * Copyright (c) 2016-2017 The strace developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
*/
#include "defs.h"
+#include "nsig.h"
+#include <regex.h>
typedef unsigned int number_slot_t;
#define BITS_PER_SLOT (sizeof(number_slot_t) * 8)
struct number_set read_set;
struct number_set write_set;
+struct number_set signal_set;
+
+static struct number_set abbrev_set[SUPPORTED_PERSONALITIES];
+static struct number_set inject_set[SUPPORTED_PERSONALITIES];
+static struct number_set raw_set[SUPPORTED_PERSONALITIES];
+static struct number_set trace_set[SUPPORTED_PERSONALITIES];
+static struct number_set verbose_set[SUPPORTED_PERSONALITIES];
static void
number_setbit(const unsigned int i, number_slot_t *const vec)
}
}
-void
+static int
+sigstr_to_uint(const char *s)
+{
+ int i;
+
+ if (*s >= '0' && *s <= '9')
+ return string_to_uint_upto(s, 255);
+
+ if (strncasecmp(s, "SIG", 3) == 0)
+ s += 3;
+
+ for (i = 0; i <= 255; ++i) {
+ const char *name = signame(i);
+
+ if (strncasecmp(name, "SIG", 3) != 0)
+ continue;
+
+ name += 3;
+
+ if (strcasecmp(name, s) != 0)
+ continue;
+
+ return i;
+ }
+
+ return -1;
+}
+
+static bool
+qualify_syscall_number(const char *s, struct number_set *set)
+{
+ int n = string_to_uint(s);
+ if (n < 0)
+ return false;
+
+ unsigned int p;
+ bool done = false;
+
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ if ((unsigned) n >= nsyscall_vec[p]) {
+ continue;
+ }
+ add_number_to_set(n, &set[p]);
+ done = true;
+ }
+
+ return done;
+}
+
+static void
+regerror_msg_and_die(int errcode, const regex_t *preg,
+ const char *str, const char *pattern)
+{
+ char buf[512];
+
+ regerror(errcode, preg, buf, sizeof(buf));
+ error_msg_and_die("%s: %s: %s", str, pattern, buf);
+}
+
+static bool
+qualify_syscall_regex(const char *s, struct number_set *set)
+{
+ regex_t preg;
+ int rc;
+
+ if ((rc = regcomp(&preg, s, REG_EXTENDED | REG_NOSUB)) != 0)
+ regerror_msg_and_die(rc, &preg, "regcomp", s);
+
+ unsigned int p;
+ bool found = false;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ unsigned int i;
+
+ for (i = 0; i < nsyscall_vec[p]; ++i) {
+ if (!sysent_vec[p][i].sys_name)
+ continue;
+ rc = regexec(&preg, sysent_vec[p][i].sys_name,
+ 0, NULL, 0);
+ if (rc == REG_NOMATCH)
+ continue;
+ else if (rc)
+ regerror_msg_and_die(rc, &preg, "regexec", s);
+ add_number_to_set(i, &set[p]);
+ found = true;
+ }
+ }
+
+ regfree(&preg);
+ return found;
+}
+
+static unsigned int
+lookup_class(const char *s)
+{
+ static const struct {
+ const char *name;
+ unsigned int value;
+ } syscall_class[] = {
+ { "desc", TRACE_DESC },
+ { "file", TRACE_FILE },
+ { "memory", TRACE_MEMORY },
+ { "process", TRACE_PROCESS },
+ { "signal", TRACE_SIGNAL },
+ { "ipc", TRACE_IPC },
+ { "network", TRACE_NETWORK },
+ { "%desc", TRACE_DESC },
+ { "%file", TRACE_FILE },
+ { "%memory", TRACE_MEMORY },
+ { "%process", TRACE_PROCESS },
+ { "%signal", TRACE_SIGNAL },
+ { "%ipc", TRACE_IPC },
+ { "%network", TRACE_NETWORK },
+ { "%stat", TRACE_STAT },
+ { "%lstat", TRACE_LSTAT },
+ { "%fstat", TRACE_FSTAT },
+ { "%%stat", TRACE_STAT_LIKE },
+ { "%statfs", TRACE_STATFS },
+ { "%fstatfs", TRACE_FSTATFS },
+ { "%%statfs", TRACE_STATFS_LIKE },
+ };
+
+ unsigned int i;
+ for (i = 0; i < ARRAY_SIZE(syscall_class); ++i) {
+ if (strcmp(s, syscall_class[i].name) == 0) {
+ return syscall_class[i].value;
+ }
+ }
+
+ return 0;
+}
+
+static bool
+qualify_syscall_class(const char *s, struct number_set *set)
+{
+ const unsigned int n = lookup_class(s);
+ if (!n)
+ return false;
+
+ unsigned int p;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ unsigned int i;
+
+ for (i = 0; i < nsyscall_vec[p]; ++i) {
+ if (!sysent_vec[p][i].sys_name
+ || (sysent_vec[p][i].sys_flags & n) != n) {
+ continue;
+ }
+ add_number_to_set(i, &set[p]);
+ }
+ }
+
+ return true;
+}
+
+static bool
+qualify_syscall_name(const char *s, struct number_set *set)
+{
+ unsigned int p;
+ bool found = false;
+
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ unsigned int i;
+
+ for (i = 0; i < nsyscall_vec[p]; ++i) {
+ if (!sysent_vec[p][i].sys_name
+ || strcmp(s, sysent_vec[p][i].sys_name)) {
+ continue;
+ }
+ add_number_to_set(i, &set[p]);
+ found = true;
+ }
+ }
+
+ return found;
+}
+
+static bool
+qualify_syscall(const char *token, struct number_set *set)
+{
+ bool ignore_fail = false;
+
+ while (*token == '?') {
+ token++;
+ ignore_fail = true;
+ }
+ if (*token >= '0' && *token <= '9')
+ return qualify_syscall_number(token, set) || ignore_fail;
+ if (*token == '/')
+ return qualify_syscall_regex(token + 1, set) || ignore_fail;
+ return qualify_syscall_class(token, set)
+ || qualify_syscall_name(token, set)
+ || ignore_fail;
+}
+
+/*
+ * Add syscall numbers to SETs for each supported personality
+ * according to STR specification.
+ */
+static void
+qualify_syscall_tokens(const char *const str, struct number_set *const set,
+ const char *const name)
+{
+ /* Clear all sets. */
+ unsigned int p;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ if (set[p].nslots)
+ memset(set[p].vec, 0,
+ sizeof(*set[p].vec) * set[p].nslots);
+ set[p].not = false;
+ }
+
+ /*
+ * Each leading ! character means inversion
+ * of the remaining specification.
+ */
+ const char *s = str;
+handle_inversion:
+ while (*s == '!') {
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ set[p].not = !set[p].not;
+ }
+ ++s;
+ }
+
+ if (strcmp(s, "none") == 0) {
+ /*
+ * No syscall numbers are added to sets.
+ * Subsequent is_number_in_set invocations
+ * will return set[p]->not.
+ */
+ return;
+ } else if (strcmp(s, "all") == 0) {
+ s = "!none";
+ goto handle_inversion;
+ }
+
+ /*
+ * Split the string into comma separated tokens.
+ * For each token, call qualify_syscall that will take care
+ * if adding appropriate syscall numbers to sets.
+ * The absence of tokens or a negative return code
+ * from qualify_syscall is a fatal error.
+ */
+ char *copy = xstrdup(s);
+ char *saveptr = NULL;
+ const char *token;
+ bool done = false;
+
+ for (token = strtok_r(copy, ",", &saveptr); token;
+ token = strtok_r(NULL, ",", &saveptr)) {
+ done = qualify_syscall(token, set);
+ if (!done) {
+ error_msg_and_die("invalid %s '%s'", name, token);
+ }
+ }
+
+ free(copy);
+
+ if (!done) {
+ error_msg_and_die("invalid %s '%s'", name, str);
+ }
+}
+
+static int
+find_errno_by_name(const char *name)
+{
+ unsigned int i;
+
+ for (i = 1; i < nerrnos; ++i) {
+ if (errnoent[i] && (strcasecmp(name, errnoent[i]) == 0))
+ return i;
+ }
+
+ return -1;
+}
+
+static bool
+parse_inject_token(const char *const token, struct inject_opts *const fopts,
+ const bool fault_tokens_only)
+{
+ const char *val;
+ int intval;
+
+ if ((val = STR_STRIP_PREFIX(token, "when=")) != token) {
+ /*
+ * == 1+1
+ * F == F+0
+ * F+ == F+1
+ * F+S
+ */
+ char *end;
+ intval = string_to_uint_ex(val, &end, 0xffff, "+");
+ if (intval < 1)
+ return false;
+
+ fopts->first = intval;
+
+ if (*end) {
+ val = end + 1;
+ if (*val) {
+ /* F+S */
+ intval = string_to_uint_upto(val, 0xffff);
+ if (intval < 1)
+ return false;
+ fopts->step = intval;
+ } else {
+ /* F+ == F+1 */
+ fopts->step = 1;
+ }
+ } else {
+ /* F == F+0 */
+ fopts->step = 0;
+ }
+ } else if ((val = STR_STRIP_PREFIX(token, "error=")) != token) {
+ if (fopts->rval != INJECT_OPTS_RVAL_DEFAULT)
+ return false;
+ intval = string_to_uint_upto(val, MAX_ERRNO_VALUE);
+ if (intval < 0)
+ intval = find_errno_by_name(val);
+ if (intval < 1)
+ return false;
+ fopts->rval = -intval;
+ } else if (!fault_tokens_only
+ && (val = STR_STRIP_PREFIX(token, "retval=")) != token) {
+ if (fopts->rval != INJECT_OPTS_RVAL_DEFAULT)
+ return false;
+ intval = string_to_uint(val);
+ if (intval < 0)
+ return false;
+ fopts->rval = intval;
+ } else if (!fault_tokens_only
+ && (val = STR_STRIP_PREFIX(token, "signal=")) != token) {
+ intval = sigstr_to_uint(val);
+ if (intval < 1 || intval > NSIG_BYTES * 8)
+ return false;
+ fopts->signo = intval;
+ } else {
+ return false;
+ }
+
+ return true;
+}
+
+static char *
+parse_inject_expression(const char *const s, char **buf,
+ struct inject_opts *const fopts,
+ const bool fault_tokens_only)
+{
+ char *saveptr = NULL;
+ char *name = NULL;
+ char *token;
+
+ *buf = xstrdup(s);
+ for (token = strtok_r(*buf, ":", &saveptr); token;
+ token = strtok_r(NULL, ":", &saveptr)) {
+ if (!name)
+ name = token;
+ else if (!parse_inject_token(token, fopts, fault_tokens_only))
+ goto parse_error;
+ }
+
+ if (name)
+ return name;
+
+parse_error:
+ free(*buf);
+ return *buf = NULL;
+}
+
+static void
qualify_read(const char *const str)
{
qualify_tokens(str, &read_set, string_to_uint, "descriptor");
}
-void
+static void
qualify_write(const char *const str)
{
qualify_tokens(str, &write_set, string_to_uint, "descriptor");
}
+
+static void
+qualify_signals(const char *const str)
+{
+ qualify_tokens(str, &signal_set, sigstr_to_uint, "signal");
+}
+
+static void
+qualify_trace(const char *const str)
+{
+ qualify_syscall_tokens(str, trace_set, "system call");
+}
+
+static void
+qualify_abbrev(const char *const str)
+{
+ qualify_syscall_tokens(str, abbrev_set, "system call");
+}
+
+static void
+qualify_verbose(const char *const str)
+{
+ qualify_syscall_tokens(str, verbose_set, "system call");
+}
+
+static void
+qualify_raw(const char *const str)
+{
+ qualify_syscall_tokens(str, raw_set, "system call");
+}
+
+static void
+qualify_inject_common(const char *const str,
+ const bool fault_tokens_only,
+ const char *const description)
+{
+ struct inject_opts opts = {
+ .first = 1,
+ .step = 1,
+ .rval = INJECT_OPTS_RVAL_DEFAULT,
+ .signo = 0
+ };
+ char *buf = NULL;
+ char *name = parse_inject_expression(str, &buf, &opts, fault_tokens_only);
+ if (!name) {
+ error_msg_and_die("invalid %s '%s'", description, str);
+ }
+
+ /* If neither of retval, error, or signal is specified, then ... */
+ if (opts.rval == INJECT_OPTS_RVAL_DEFAULT && !opts.signo) {
+ if (fault_tokens_only) {
+ /* in fault= syntax the default error code is ENOSYS. */
+ opts.rval = -ENOSYS;
+ } else {
+ /* in inject= syntax this is not allowed. */
+ error_msg_and_die("invalid %s '%s'", description, str);
+ }
+ }
+
+ struct number_set tmp_set[SUPPORTED_PERSONALITIES];
+ memset(tmp_set, 0, sizeof(tmp_set));
+ qualify_syscall_tokens(name, tmp_set, description);
+
+ free(buf);
+
+ /*
+ * Initialize inject_vec accourding to tmp_set.
+ * Merge tmp_set into inject_set.
+ */
+ unsigned int p;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ if (!tmp_set[p].nslots && !tmp_set[p].not) {
+ continue;
+ }
+
+ if (!inject_vec[p]) {
+ inject_vec[p] = xcalloc(nsyscall_vec[p],
+ sizeof(*inject_vec[p]));
+ }
+
+ unsigned int i;
+ for (i = 0; i < nsyscall_vec[p]; ++i) {
+ if (is_number_in_set(i, &tmp_set[p])) {
+ add_number_to_set(i, &inject_set[p]);
+ inject_vec[p][i] = opts;
+ }
+ }
+
+ free(tmp_set[p].vec);
+ }
+}
+
+static void
+qualify_fault(const char *const str)
+{
+ qualify_inject_common(str, true, "fault argument");
+}
+
+static void
+qualify_inject(const char *const str)
+{
+ qualify_inject_common(str, false, "inject argument");
+}
+
+static const struct qual_options {
+ const char *name;
+ void (*qualify)(const char *);
+} qual_options[] = {
+ { "trace", qualify_trace },
+ { "t", qualify_trace },
+ { "abbrev", qualify_abbrev },
+ { "a", qualify_abbrev },
+ { "verbose", qualify_verbose },
+ { "v", qualify_verbose },
+ { "raw", qualify_raw },
+ { "x", qualify_raw },
+ { "signal", qualify_signals },
+ { "signals", qualify_signals },
+ { "s", qualify_signals },
+ { "read", qualify_read },
+ { "reads", qualify_read },
+ { "r", qualify_read },
+ { "write", qualify_write },
+ { "writes", qualify_write },
+ { "w", qualify_write },
+ { "fault", qualify_fault },
+ { "inject", qualify_inject },
+};
+
+void
+qualify(const char *str)
+{
+ const struct qual_options *opt = qual_options;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(qual_options); ++i) {
+ const char *name = qual_options[i].name;
+ const size_t len = strlen(name);
+ const char *val = str_strip_prefix_len(str, name, len);
+
+ if (val == str || *val != '=')
+ continue;
+ str = val + 1;
+ opt = &qual_options[i];
+ break;
+ }
+
+ opt->qualify(str);
+}
+
+unsigned int
+qual_flags(const unsigned int scno)
+{
+ return (is_number_in_set(scno, &trace_set[current_personality])
+ ? QUAL_TRACE : 0)
+ | (is_number_in_set(scno, &abbrev_set[current_personality])
+ ? QUAL_ABBREV : 0)
+ | (is_number_in_set(scno, &verbose_set[current_personality])
+ ? QUAL_VERBOSE : 0)
+ | (is_number_in_set(scno, &raw_set[current_personality])
+ ? QUAL_RAW : 0)
+ | (is_number_in_set(scno, &inject_set[current_personality])
+ ? QUAL_INJECT : 0);
+}