X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Ferr%2Ferr.c;h=25ab13509ce0114f659386dd437bd5d825d52402;hp=07911e25b22b844fbcbf6342ff692ac39c6b771e;hb=fe6ec26b204a056aee2a24b79df09a45b2308603;hpb=e1a4ff7678ef8fd2d67416f84a7408e826c7dccc

diff --git a/crypto/err/err.c b/crypto/err/err.c
index 07911e25b2..25ab13509c 100644
--- a/crypto/err/err.c
+++ b/crypto/err/err.c
@@ -1,7 +1,7 @@
 /*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
  *
- * Licensed under the OpenSSL license (the "License").  You may not use
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
@@ -10,16 +10,19 @@
 #include <stdio.h>
 #include <stdarg.h>
 #include <string.h>
-#include <internal/cryptlib_int.h>
-#include <internal/err.h>
-#include <internal/err_int.h>
-#include <openssl/lhash.h>
+#include "internal/cryptlib_int.h"
+#include "internal/err.h"
+#include "internal/err_int.h"
 #include <openssl/err.h>
 #include <openssl/crypto.h>
 #include <openssl/buffer.h>
 #include <openssl/bio.h>
 #include <openssl/opensslconf.h>
-#include <internal/thread_once.h>
+#include "internal/thread_once.h"
+#include "internal/ctype.h"
+#include "internal/constant_time_locl.h"
+#include "e_os.h"
+#include "err_locl.h"
 
 static int err_load_strings(const ERR_STRING_DATA *str);
 
@@ -56,40 +59,15 @@ static ERR_STRING_DATA ERR_str_libraries[] = {
     {ERR_PACK(ERR_LIB_UI, 0, 0), "UI routines"},
     {ERR_PACK(ERR_LIB_FIPS, 0, 0), "FIPS routines"},
     {ERR_PACK(ERR_LIB_CMS, 0, 0), "CMS routines"},
+    {ERR_PACK(ERR_LIB_CRMF, 0, 0), "CRMF routines"},
+    {ERR_PACK(ERR_LIB_CMP, 0, 0), "CMP routines"},
     {ERR_PACK(ERR_LIB_HMAC, 0, 0), "HMAC routines"},
     {ERR_PACK(ERR_LIB_CT, 0, 0), "CT routines"},
     {ERR_PACK(ERR_LIB_ASYNC, 0, 0), "ASYNC routines"},
-    {ERR_PACK(ERR_LIB_KDF, 0, 0), "KDF routines"},
     {ERR_PACK(ERR_LIB_OSSL_STORE, 0, 0), "STORE routines"},
-    {0, NULL},
-};
-
-static ERR_STRING_DATA ERR_str_functs[] = {
-    {ERR_PACK(0, SYS_F_FOPEN, 0), "fopen"},
-    {ERR_PACK(0, SYS_F_CONNECT, 0), "connect"},
-    {ERR_PACK(0, SYS_F_GETSERVBYNAME, 0), "getservbyname"},
-    {ERR_PACK(0, SYS_F_SOCKET, 0), "socket"},
-    {ERR_PACK(0, SYS_F_IOCTLSOCKET, 0), "ioctlsocket"},
-    {ERR_PACK(0, SYS_F_BIND, 0), "bind"},
-    {ERR_PACK(0, SYS_F_LISTEN, 0), "listen"},
-    {ERR_PACK(0, SYS_F_ACCEPT, 0), "accept"},
-# ifdef OPENSSL_SYS_WINDOWS
-    {ERR_PACK(0, SYS_F_WSASTARTUP, 0), "WSAstartup"},
-# endif
-    {ERR_PACK(0, SYS_F_OPENDIR, 0), "opendir"},
-    {ERR_PACK(0, SYS_F_FREAD, 0), "fread"},
-    {ERR_PACK(0, SYS_F_GETADDRINFO, 0), "getaddrinfo"},
-    {ERR_PACK(0, SYS_F_GETNAMEINFO, 0), "getnameinfo"},
-    {ERR_PACK(0, SYS_F_SETSOCKOPT, 0), "setsockopt"},
-    {ERR_PACK(0, SYS_F_GETSOCKOPT, 0), "getsockopt"},
-    {ERR_PACK(0, SYS_F_GETSOCKNAME, 0), "getsockname"},
-    {ERR_PACK(0, SYS_F_GETHOSTBYNAME, 0), "gethostbyname"},
-    {ERR_PACK(0, SYS_F_FFLUSH, 0), "fflush"},
-    {ERR_PACK(0, SYS_F_OPEN, 0), "open"},
-    {ERR_PACK(0, SYS_F_CLOSE, 0), "close"},
-    {ERR_PACK(0, SYS_F_IOCTL, 0), "ioctl"},
-    {ERR_PACK(0, SYS_F_STAT, 0), "stat"},
-    {ERR_PACK(0, SYS_F_FCNTL, 0), "fcntl"},
+    {ERR_PACK(ERR_LIB_SM2, 0, 0), "SM2 routines"},
+    {ERR_PACK(ERR_LIB_ESS, 0, 0), "ESS routines"},
+    {ERR_PACK(ERR_LIB_PROV, 0, 0), "Provider routines"},
     {0, NULL},
 };
 
@@ -156,7 +134,7 @@ static unsigned long err_string_data_hash(const ERR_STRING_DATA *a)
     unsigned long ret, l;
 
     l = a->error;
-    ret = l ^ ERR_GET_LIB(l) ^ ERR_GET_FUNC(l);
+    ret = l ^ ERR_GET_LIB(l);
     return (ret ^ ret % 19 * 13);
 }
 
@@ -180,8 +158,9 @@ static ERR_STRING_DATA *int_err_get_item(const ERR_STRING_DATA *d)
 }
 
 #ifndef OPENSSL_NO_ERR
+/* 2019-05-21: Russian and Ukrainian locales on Linux require more than 6,5 kB */
+# define SPACE_SYS_STR_REASONS 8 * 1024
 # define NUM_SYS_STR_REASONS 127
-# define LEN_SYS_STR_REASON 32
 
 static ERR_STRING_DATA SYS_str_reasons[NUM_SYS_STR_REASONS + 1];
 /*
@@ -197,9 +176,12 @@ static ERR_STRING_DATA SYS_str_reasons[NUM_SYS_STR_REASONS + 1];
 static void build_SYS_str_reasons(void)
 {
     /* OPENSSL_malloc cannot be used here, use static storage instead */
-    static char strerror_tab[NUM_SYS_STR_REASONS][LEN_SYS_STR_REASON];
+    static char strerror_pool[SPACE_SYS_STR_REASONS];
+    char *cur = strerror_pool;
+    size_t cnt = 0;
     static int init = 1;
     int i;
+    int saveerrno = get_last_sys_error();
 
     CRYPTO_THREAD_write_lock(err_string_lock);
     if (!init) {
@@ -211,10 +193,29 @@ static void build_SYS_str_reasons(void)
         ERR_STRING_DATA *str = &SYS_str_reasons[i - 1];
 
         str->error = ERR_PACK(ERR_LIB_SYS, 0, i);
-        if (str->string == NULL) {
-            char (*dest)[LEN_SYS_STR_REASON] = &(strerror_tab[i - 1]);
-            if (openssl_strerror_r(i, *dest, sizeof(*dest)))
-                str->string = *dest;
+        /*
+         * If we have used up all the space in strerror_pool,
+         * there's no point in calling openssl_strerror_r()
+         */
+        if (str->string == NULL && cnt < sizeof(strerror_pool)) {
+            if (openssl_strerror_r(i, cur, sizeof(strerror_pool) - cnt)) {
+                size_t l = strlen(cur);
+
+                str->string = cur;
+                cnt += l;
+                cur += l;
+
+                /*
+                 * VMS has an unusual quirk of adding spaces at the end of
+                 * some (most? all?) messages. Lets trim them off.
+                 */
+                while (cur > strerror_pool && ossl_isspace(cur[-1])) {
+                    cur--;
+                    cnt--;
+                }
+                *cur++ = '\0';
+                cnt++;
+            }
         }
         if (str->string == NULL)
             str->string = "unknown";
@@ -228,49 +229,39 @@ static void build_SYS_str_reasons(void)
     init = 0;
 
     CRYPTO_THREAD_unlock(err_string_lock);
+    /* openssl_strerror_r could change errno, but we want to preserve it */
+    set_sys_error(saveerrno);
     err_load_strings(SYS_str_reasons);
 }
 #endif
 
-#define err_clear_data(p,i) \
-        do { \
-        if ((p)->err_data_flags[i] & ERR_TXT_MALLOCED) \
-                {  \
-                OPENSSL_free((p)->err_data[i]); \
-                (p)->err_data[i]=NULL; \
-                } \
-        (p)->err_data_flags[i]=0; \
-        } while(0)
-
-#define err_clear(p,i) \
-        do { \
-        (p)->err_flags[i]=0; \
-        (p)->err_buffer[i]=0; \
-        err_clear_data(p,i); \
-        (p)->err_file[i]=NULL; \
-        (p)->err_line[i]= -1; \
-        } while(0)
-
 static void ERR_STATE_free(ERR_STATE *s)
 {
     int i;
 
     if (s == NULL)
         return;
-
     for (i = 0; i < ERR_NUM_ERRORS; i++) {
-        err_clear_data(s, i);
+        err_clear_data(s, i, 1);
     }
     OPENSSL_free(s);
 }
 
 DEFINE_RUN_ONCE_STATIC(do_err_strings_init)
 {
-    OPENSSL_init_crypto(0, NULL);
+    if (!OPENSSL_init_crypto(0, NULL))
+        return 0;
     err_string_lock = CRYPTO_THREAD_lock_new();
+    if (err_string_lock == NULL)
+        return 0;
     int_error_hash = lh_ERR_STRING_DATA_new(err_string_data_hash,
                                             err_string_data_cmp);
-    return err_string_lock != NULL && int_error_hash != NULL;
+    if (int_error_hash == NULL) {
+        CRYPTO_THREAD_lock_free(err_string_lock);
+        err_string_lock = NULL;
+        return 0;
+    }
+    return 1;
 }
 
 void err_cleanup(void)
@@ -315,8 +306,6 @@ int ERR_load_ERR_strings(void)
 
     err_load_strings(ERR_str_libraries);
     err_load_strings(ERR_str_reasons);
-    err_patch(ERR_LIB_SYS, ERR_str_functs);
-    err_load_strings(ERR_str_functs);
     build_SYS_str_reasons();
 #endif
     return 1;
@@ -365,43 +354,6 @@ void err_free_strings_int(void)
 
 /********************************************************/
 
-void ERR_put_error(int lib, int func, int reason, const char *file, int line)
-{
-    ERR_STATE *es;
-
-#ifdef _OSD_POSIX
-    /*
-     * In the BS2000-OSD POSIX subsystem, the compiler generates path names
-     * in the form "*POSIX(/etc/passwd)". This dirty hack strips them to
-     * something sensible. @@@ We shouldn't modify a const string, though.
-     */
-    if (strncmp(file, "*POSIX(", sizeof("*POSIX(") - 1) == 0) {
-        char *end;
-
-        /* Skip the "*POSIX(" prefix */
-        file += sizeof("*POSIX(") - 1;
-        end = &file[strlen(file) - 1];
-        if (*end == ')')
-            *end = '\0';
-        /* Optional: use the basename of the path only. */
-        if ((end = strrchr(file, '/')) != NULL)
-            file = &end[1];
-    }
-#endif
-    es = ERR_get_state();
-    if (es == NULL)
-        return;
-
-    es->top = (es->top + 1) % ERR_NUM_ERRORS;
-    if (es->top == es->bottom)
-        es->bottom = (es->bottom + 1) % ERR_NUM_ERRORS;
-    es->err_flags[es->top] = 0;
-    es->err_buffer[es->top] = ERR_PACK(lib, func, reason);
-    es->err_file[es->top] = file;
-    es->err_line[es->top] = line;
-    err_clear_data(es, es->top);
-}
-
 void ERR_clear_error(void)
 {
     int i;
@@ -412,57 +364,57 @@ void ERR_clear_error(void)
         return;
 
     for (i = 0; i < ERR_NUM_ERRORS; i++) {
-        err_clear(es, i);
+        err_clear(es, i, 0);
     }
     es->top = es->bottom = 0;
 }
 
 unsigned long ERR_get_error(void)
 {
-    return (get_error_values(1, 0, NULL, NULL, NULL, NULL));
+    return get_error_values(1, 0, NULL, NULL, NULL, NULL);
 }
 
 unsigned long ERR_get_error_line(const char **file, int *line)
 {
-    return (get_error_values(1, 0, file, line, NULL, NULL));
+    return get_error_values(1, 0, file, line, NULL, NULL);
 }
 
 unsigned long ERR_get_error_line_data(const char **file, int *line,
                                       const char **data, int *flags)
 {
-    return (get_error_values(1, 0, file, line, data, flags));
+    return get_error_values(1, 0, file, line, data, flags);
 }
 
 unsigned long ERR_peek_error(void)
 {
-    return (get_error_values(0, 0, NULL, NULL, NULL, NULL));
+    return get_error_values(0, 0, NULL, NULL, NULL, NULL);
 }
 
 unsigned long ERR_peek_error_line(const char **file, int *line)
 {
-    return (get_error_values(0, 0, file, line, NULL, NULL));
+    return get_error_values(0, 0, file, line, NULL, NULL);
 }
 
 unsigned long ERR_peek_error_line_data(const char **file, int *line,
                                        const char **data, int *flags)
 {
-    return (get_error_values(0, 0, file, line, data, flags));
+    return get_error_values(0, 0, file, line, data, flags);
 }
 
 unsigned long ERR_peek_last_error(void)
 {
-    return (get_error_values(0, 1, NULL, NULL, NULL, NULL));
+    return get_error_values(0, 1, NULL, NULL, NULL, NULL);
 }
 
 unsigned long ERR_peek_last_error_line(const char **file, int *line)
 {
-    return (get_error_values(0, 1, file, line, NULL, NULL));
+    return get_error_values(0, 1, file, line, NULL, NULL);
 }
 
 unsigned long ERR_peek_last_error_line_data(const char **file, int *line,
                                             const char **data, int *flags)
 {
-    return (get_error_values(0, 1, file, line, data, flags));
+    return get_error_values(0, 1, file, line, data, flags);
 }
 
 static unsigned long get_error_values(int inc, int top, const char **file,
@@ -490,8 +442,24 @@ static unsigned long get_error_values(int inc, int top, const char **file,
         return ERR_R_INTERNAL_ERROR;
     }
 
+    while (es->bottom != es->top) {
+        if (es->err_flags[es->top] & ERR_FLAG_CLEAR) {
+            err_clear(es, es->top, 0);
+            es->top = es->top > 0 ? es->top - 1 : ERR_NUM_ERRORS - 1;
+            continue;
+        }
+        i = (es->bottom + 1) % ERR_NUM_ERRORS;
+        if (es->err_flags[i] & ERR_FLAG_CLEAR) {
+            es->bottom = i;
+            err_clear(es, es->bottom, 0);
+            continue;
+        }
+        break;
+    }
+
     if (es->bottom == es->top)
         return 0;
+
     if (top)
         i = es->top;            /* last error */
     else
@@ -503,21 +471,19 @@ static unsigned long get_error_values(int inc, int top, const char **file,
         es->err_buffer[i] = 0;
     }
 
-    if ((file != NULL) && (line != NULL)) {
+    if (file != NULL && line != NULL) {
         if (es->err_file[i] == NULL) {
             *file = "NA";
-            if (line != NULL)
-                *line = 0;
+            *line = 0;
         } else {
             *file = es->err_file[i];
-            if (line != NULL)
-                *line = es->err_line[i];
+            *line = es->err_line[i];
         }
     }
 
     if (data == NULL) {
         if (inc) {
-            err_clear_data(es, i);
+            err_clear_data(es, i, 0);
         }
     } else {
         if (es->err_data[i] == NULL) {
@@ -535,53 +501,31 @@ static unsigned long get_error_values(int inc, int top, const char **file,
 
 void ERR_error_string_n(unsigned long e, char *buf, size_t len)
 {
-    char lsbuf[64], fsbuf[64], rsbuf[64];
-    const char *ls, *fs, *rs;
-    unsigned long l, f, r;
+    char lsbuf[64], rsbuf[64];
+    const char *ls, *rs;
+    unsigned long f = 0, l, r;
 
     if (len == 0)
         return;
 
     l = ERR_GET_LIB(e);
-    f = ERR_GET_FUNC(e);
-    r = ERR_GET_REASON(e);
-
     ls = ERR_lib_error_string(e);
-    fs = ERR_func_error_string(e);
-    rs = ERR_reason_error_string(e);
-
-    if (ls == NULL)
+    if (ls == NULL) {
         BIO_snprintf(lsbuf, sizeof(lsbuf), "lib(%lu)", l);
-    if (fs == NULL)
-        BIO_snprintf(fsbuf, sizeof(fsbuf), "func(%lu)", f);
-    if (rs == NULL)
+        ls = lsbuf;
+    }
+
+    rs = ERR_reason_error_string(e);
+    r = ERR_GET_REASON(e);
+    if (rs == NULL) {
         BIO_snprintf(rsbuf, sizeof(rsbuf), "reason(%lu)", r);
+        rs = rsbuf;
+    }
 
-    BIO_snprintf(buf, len, "error:%08lX:%s:%s:%s", e, ls ? ls : lsbuf,
-                 fs ? fs : fsbuf, rs ? rs : rsbuf);
+    BIO_snprintf(buf, len, "error:%08lX:%s:%s:%s", e, ls, "", rs);
     if (strlen(buf) == len - 1) {
-        /*
-         * output may be truncated; make sure we always have 5
-         * colon-separated fields, i.e. 4 colons ...
-         */
-#define NUM_COLONS 4
-        if (len > NUM_COLONS) { /* ... if possible */
-            int i;
-            char *s = buf;
-
-            for (i = 0; i < NUM_COLONS; i++) {
-                char *colon = strchr(s, ':');
-                if (colon == NULL || colon > &buf[len - 1] - NUM_COLONS + i) {
-                    /*
-                     * set colon no. i at last possible position (buf[len-1]
-                     * is the terminating 0)
-                     */
-                    colon = &buf[len - 1] - NUM_COLONS + i;
-                    *colon = ':';
-                }
-                s = colon + 1;
-            }
-        }
+        /* Didn't fit; use a minimal format. */
+        BIO_snprintf(buf, len, "err:%lx:%lx:%lx:%lx", e, l, f, r);
     }
 }
 
@@ -595,8 +539,7 @@ char *ERR_error_string(unsigned long e, char *ret)
 
     if (ret == NULL)
         ret = buf;
-    ERR_error_string_n(e, ret, 256);
-
+    ERR_error_string_n(e, ret, (int)sizeof(buf));
     return ret;
 }
 
@@ -617,18 +560,9 @@ const char *ERR_lib_error_string(unsigned long e)
 
 const char *ERR_func_error_string(unsigned long e)
 {
-    ERR_STRING_DATA d, *p;
-    unsigned long l, f;
-
-    if (!RUN_ONCE(&err_string_init, do_err_strings_init)) {
+    if (!RUN_ONCE(&err_string_init, do_err_strings_init))
         return NULL;
-    }
-
-    l = ERR_GET_LIB(e);
-    f = ERR_GET_FUNC(e);
-    d.error = ERR_PACK(l, f, 0);
-    p = int_err_get_item(&d);
-    return ((p == NULL) ? NULL : p->string);
+    return ERR_GET_LIB(e) == ERR_LIB_SYS ? "system library" : NULL;
 }
 
 const char *ERR_reason_error_string(unsigned long e)
@@ -651,7 +585,8 @@ const char *ERR_reason_error_string(unsigned long e)
     return ((p == NULL) ? NULL : p->string);
 }
 
-void err_delete_thread_state(void)
+/* TODO(3.0): arg ignored for now */
+static void err_delete_thread_state(void *arg)
 {
     ERR_STATE *state = CRYPTO_THREAD_get_local(&err_thread_local);
     if (state == NULL)
@@ -661,13 +596,13 @@ void err_delete_thread_state(void)
     ERR_STATE_free(state);
 }
 
-#if OPENSSL_API_COMPAT < 0x10100000L
+#if !OPENSSL_API_1_1_0
 void ERR_remove_thread_state(void *dummy)
 {
 }
 #endif
 
-#if OPENSSL_API_COMPAT < 0x10000000L
+#if !OPENSSL_API_1_0_0
 void ERR_remove_state(unsigned long pid)
 {
 }
@@ -681,21 +616,32 @@ DEFINE_RUN_ONCE_STATIC(err_do_init)
 
 ERR_STATE *ERR_get_state(void)
 {
-    ERR_STATE *state = NULL;
+    ERR_STATE *state;
+    int saveerrno = get_last_sys_error();
+
+    if (!OPENSSL_init_crypto(OPENSSL_INIT_BASE_ONLY, NULL))
+        return NULL;
 
     if (!RUN_ONCE(&err_init, err_do_init))
         return NULL;
 
     state = CRYPTO_THREAD_get_local(&err_thread_local);
+    if (state == (ERR_STATE*)-1)
+        return NULL;
 
     if (state == NULL) {
-        state = OPENSSL_zalloc(sizeof(*state));
-        if (state == NULL)
+        if (!CRYPTO_THREAD_set_local(&err_thread_local, (ERR_STATE*)-1))
             return NULL;
 
-        if (!ossl_init_thread_start(OPENSSL_INIT_THREAD_ERR_STATE)
-            || !CRYPTO_THREAD_set_local(&err_thread_local, state)) {
+        if ((state = OPENSSL_zalloc(sizeof(*state))) == NULL) {
+            CRYPTO_THREAD_set_local(&err_thread_local, NULL);
+            return NULL;
+        }
+
+        if (!ossl_init_thread_start(NULL, NULL, err_delete_thread_state)
+                || !CRYPTO_THREAD_set_local(&err_thread_local, state)) {
             ERR_STATE_free(state);
+            CRYPTO_THREAD_set_local(&err_thread_local, NULL);
             return NULL;
         }
 
@@ -703,16 +649,60 @@ ERR_STATE *ERR_get_state(void)
         OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
     }
 
+    set_sys_error(saveerrno);
     return state;
 }
 
+/*
+ * err_shelve_state returns the current thread local error state
+ * and freezes the error module until err_unshelve_state is called.
+ */
+int err_shelve_state(void **state)
+{
+    int saveerrno = get_last_sys_error();
+
+    /*
+     * Note, at present our only caller is OPENSSL_init_crypto(), indirectly
+     * via ossl_init_load_crypto_nodelete(), by which point the requested
+     * "base" initialization has already been performed, so the below call is a
+     * NOOP, that re-enters OPENSSL_init_crypto() only to quickly return.
+     *
+     * If are no other valid callers of this function, the call below can be
+     * removed, avoiding the re-entry into OPENSSL_init_crypto().  If there are
+     * potential uses that are not from inside OPENSSL_init_crypto(), then this
+     * call is needed, but some care is required to make sure that the re-entry
+     * remains a NOOP.
+     */
+    if (!OPENSSL_init_crypto(OPENSSL_INIT_BASE_ONLY, NULL))
+        return 0;
+
+    if (!RUN_ONCE(&err_init, err_do_init))
+        return 0;
+
+    *state = CRYPTO_THREAD_get_local(&err_thread_local);
+    if (!CRYPTO_THREAD_set_local(&err_thread_local, (ERR_STATE*)-1))
+        return 0;
+
+    set_sys_error(saveerrno);
+    return 1;
+}
+
+/*
+ * err_unshelve_state restores the error state that was returned
+ * by err_shelve_state previously.
+ */
+void err_unshelve_state(void* state)
+{
+    if (state != (void*)-1)
+        CRYPTO_THREAD_set_local(&err_thread_local, (ERR_STATE*)state);
+}
+
 int ERR_get_next_error_library(void)
 {
     int ret;
 
-    if (!RUN_ONCE(&err_string_init, do_err_strings_init)) {
+    if (!RUN_ONCE(&err_string_init, do_err_strings_init))
         return 0;
-    }
 
     CRYPTO_THREAD_write_lock(err_string_lock);
     ret = int_err_library_number++;
@@ -720,22 +710,38 @@ int ERR_get_next_error_library(void)
     return ret;
 }
 
-void ERR_set_error_data(char *data, int flags)
+static int err_set_error_data_int(char *data, size_t size, int flags,
+                                  int deallocate)
 {
     ERR_STATE *es;
-    int i;
 
     es = ERR_get_state();
     if (es == NULL)
-        return;
+        return 0;
 
-    i = es->top;
-    if (i == 0)
-        i = ERR_NUM_ERRORS - 1;
+    err_clear_data(es, es->top, deallocate);
+    err_set_data(es, es->top, data, size, flags);
 
-    err_clear_data(es, i);
-    es->err_data[i] = data;
-    es->err_data_flags[i] = flags;
+    return 1;
+}
+
+void ERR_set_error_data(char *data, int flags)
+{
+    /*
+     * This function is void so we cannot propagate the error return. Since it
+     * is also in the public API we can't change the return type.
+     *
+     * We estimate the size of the data.  If it's not flagged as allocated,
+     * then this is safe, and if it is flagged as allocated, then our size
+     * may be smaller than the actual allocation, but that doesn't matter
+     * too much, the buffer will remain untouched or will eventually be
+     * reallocated to a new size.
+     *
+     * callers should be advised that this function takes over ownership of
+     * the allocated memory, i.e. they can't count on the pointer to remain
+     * valid.
+     */
+    err_set_error_data_int(data, strlen(data) + 1, flags, 1);
 }
 
 void ERR_add_error_data(int num, ...)
@@ -748,33 +754,61 @@ void ERR_add_error_data(int num, ...)
 
 void ERR_add_error_vdata(int num, va_list args)
 {
-    int i, n, s;
-    char *str, *p, *a;
+    int i, len, size;
+    int flags = ERR_TXT_MALLOCED | ERR_TXT_STRING;
+    char *str, *arg;
+    ERR_STATE *es;
+
+    /* Get the current error data; if an allocated string get it. */
+    es = ERR_get_state();
+    if (es == NULL)
+        return;
+    i = es->top;
+
+    /*
+     * If err_data is allocated already, re-use the space.
+     * Otherwise, allocate a small new buffer.
+     */
+    if ((es->err_data_flags[i] & flags) == flags) {
+        str = es->err_data[i];
+        size = es->err_data_size[i];
 
-    s = 80;
-    str = OPENSSL_malloc(s + 1);
-    if (str == NULL)
+        /*
+         * To protect the string we just grabbed from tampering by other
+         * functions we may call, or to protect them from freeing a pointer
+         * that may no longer be valid at that point, we clear away the
+         * data pointer and the flags.  We will set them again at the end
+         * of this function.
+         */
+        es->err_data[i] = NULL;
+        es->err_data_flags[i] = 0;
+    } else if ((str = OPENSSL_malloc(size = 81)) == NULL) {
         return;
-    str[0] = '\0';
-
-    n = 0;
-    for (i = 0; i < num; i++) {
-        a = va_arg(args, char *);
-        if (a == NULL)
-            a = "<NULL>";
-        n += strlen(a);
-        if (n > s) {
-            s = n + 20;
-            p = OPENSSL_realloc(str, s + 1);
+    } else {
+        str[0] = '\0';
+    }
+    len = strlen(str);
+
+    while (--num >= 0) {
+        arg = va_arg(args, char *);
+        if (arg == NULL)
+            arg = "<NULL>";
+        len += strlen(arg);
+        if (len >= size) {
+            char *p;
+
+            size = len + 20;
+            p = OPENSSL_realloc(str, size);
             if (p == NULL) {
                 OPENSSL_free(str);
                 return;
             }
             str = p;
         }
-        OPENSSL_strlcat(str, a, (size_t)s + 1);
+        OPENSSL_strlcat(str, arg, (size_t)size);
     }
-    ERR_set_error_data(str, ERR_TXT_MALLOCED | ERR_TXT_STRING);
+    if (!err_set_error_data_int(str, size, flags, 0))
+        OPENSSL_free(str);
 }
 
 int ERR_set_mark(void)
@@ -801,10 +835,8 @@ int ERR_pop_to_mark(void)
 
     while (es->bottom != es->top
            && (es->err_flags[es->top] & ERR_FLAG_MARK) == 0) {
-        err_clear(es, es->top);
-        es->top -= 1;
-        if (es->top == -1)
-            es->top = ERR_NUM_ERRORS - 1;
+        err_clear(es, es->top, 0);
+        es->top = es->top > 0 ? es->top - 1 : ERR_NUM_ERRORS - 1;
     }
 
     if (es->bottom == es->top)
@@ -825,9 +857,7 @@ int ERR_clear_last_mark(void)
     top = es->top;
     while (es->bottom != top
            && (es->err_flags[top] & ERR_FLAG_MARK) == 0) {
-        top -= 1;
-        if (top == -1)
-            top = ERR_NUM_ERRORS - 1;
+        top = top > 0 ? top - 1 : ERR_NUM_ERRORS - 1;
     }
 
     if (es->bottom == top)
@@ -835,3 +865,23 @@ int ERR_clear_last_mark(void)
     es->err_flags[top] &= ~ERR_FLAG_MARK;
     return 1;
 }
+
+void err_clear_last_constant_time(int clear)
+{
+    ERR_STATE *es;
+    int top;
+
+    es = ERR_get_state();
+    if (es == NULL)
+        return;
+
+    top = es->top;
+
+    /*
+     * Flag error as cleared but remove it elsewhere to avoid two errors
+     * accessing the same error stack location, revealing timing information.
+     */
+    clear = constant_time_select_int(constant_time_eq_int(clear, 0),
+                                     0, ERR_FLAG_CLEAR);
+    es->err_flags[top] |= clear;
+}