Remove use of strcpy() and sprintf().

[tinc] / src / utils.c

diff --git a/src/utils.c b/src/utils.c
index edaa354..c374eb5 100644 (file)
--- a/src/utils.c
+++ b/src/utils.c
@@ -18,10 +18,10 @@
     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
+#include "logger.h"
 #include "system.h"
-
-#include "../src/logger.h"
 #include "utils.h"
+#include "xalloc.h"
 
 static const char hexadecimals[] = "0123456789ABCDEF";
 static const char base64_original[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
@@ -52,14 +52,16 @@ static int charhex2bin(char c) {
                return toupper(c) - 'A' + 10;
 }
 
-int hex2bin(const char *src, char *dst, int length) {
+int hex2bin(const char *src, void *vdst, int length) {
+       char *dst = vdst;
        int i;
        for(i = 0; i < length && isxdigit(src[i * 2]) && isxdigit(src[i * 2 + 1]); i++)
                dst[i] = charhex2bin(src[i * 2]) * 16 + charhex2bin(src[i * 2 + 1]);
        return i;
 }
 
-int bin2hex(const char *src, char *dst, int length) {
+int bin2hex(const void *vsrc, char *dst, int length) {
+       const char *src = vsrc;
        for(int i = length - 1; i >= 0; i--) {
                dst[i * 2 + 1] = hexadecimals[(unsigned char) src[i] & 15];
                dst[i * 2] = hexadecimals[(unsigned char) src[i] >> 4];
@@ -68,12 +70,12 @@ int bin2hex(const char *src, char *dst, int length) {
        return length * 2;
 }
 
-int b64decode(const char *src, char *dst, int length) {
+int b64decode(const char *src, void *dst, int length) {
        int i;
        uint32_t triplet = 0;
        unsigned char *udst = (unsigned char *)dst;
 
-       for(i = 0; i < length / 3 * 4 && src[i]; i++) {
+       for(i = 0; i < length && src[i]; i++) {
                triplet |= base64_decode[src[i] & 0xff] << (6 * (i & 3));
                if((i & 3) == 3) {
                        if(triplet & 0xff000000U)
@@ -99,7 +101,7 @@ int b64decode(const char *src, char *dst, int length) {
        }
 }
 
-static int b64encode_internal(const char *src, char *dst, int length, const char *alphabet) {
+static int b64encode_internal(const void *src, char *dst, int length, const char *alphabet) {
        uint32_t triplet;
        const unsigned char *usrc = (unsigned char *)src;
        int si = length / 3 * 3;
@@ -112,14 +114,14 @@ static int b64encode_internal(const char *src, char *dst, int length, const char
                        dst[di + 1] = alphabet[triplet & 63]; triplet >>= 6;
                        dst[di + 2] = alphabet[triplet];
                        dst[di + 3] = 0;
-                       length = di + 2;
+                       length = di + 3;
                        break;
                case 1:
                        triplet = usrc[si];
                        dst[di] = alphabet[triplet & 63]; triplet >>= 6;
                        dst[di + 1] = alphabet[triplet];
                        dst[di + 2] = 0;
-                       length = di + 1;
+                       length = di + 2;
                        break;
                default:
                        dst[di] = 0;
@@ -140,11 +142,11 @@ static int b64encode_internal(const char *src, char *dst, int length, const char
        return length;
 }
 
-int b64encode(const char *src, char *dst, int length) {
+int b64encode(const void *src, char *dst, int length) {
        return b64encode_internal(src, dst, length, base64_original);
 }
 
-int b64encode_urlsafe(const char *src, char *dst, int length) {
+int b64encode_urlsafe(const void *src, char *dst, int length) {
        return b64encode_internal(src, dst, length, base64_urlsafe);
 }
 
@@ -156,7 +158,7 @@ int b64encode_urlsafe(const char *src, char *dst, int length) {
 const char *winerror(int err) {
        static char buf[1024], *ptr;
 
-       ptr = buf + sprintf(buf, "(%d) ", err);
+       ptr = buf + snprintf(buf, sizeof buf, "(%d) ", err);
 
        if (!FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
                NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), ptr, sizeof(buf) - (ptr - buf), NULL)) {
@@ -177,3 +179,54 @@ unsigned int bitfield_to_int(const void *bitfield, size_t size) {
        memcpy(&value, bitfield, size);
        return value;
 }
+
+bool check_id(const char *id) {
+       if(!id || !*id)
+               return false;
+
+       for(; *id; id++)
+               if(!isalnum(*id) && *id != '_')
+                       return false;
+
+       return true;
+}
+
+/* Windows doesn't define HOST_NAME_MAX. */
+#ifndef HOST_NAME_MAX
+#define HOST_NAME_MAX 255
+#endif
+
+char *replace_name(const char *name) {
+       char *ret_name;
+
+       if (name[0] == '$') {
+               char *envname = getenv(name + 1);
+               char hostname[HOST_NAME_MAX+1];
+               if (!envname) {
+                       if (strcmp(name + 1, "HOST")) {
+                               logger(DEBUG_ALWAYS, LOG_ERR, "Invalid Name: environment variable %s does not exist\n", name + 1);
+                               return NULL;
+                       }
+                       if (gethostname(hostname, sizeof hostname) || !*hostname) {
+                               logger(DEBUG_ALWAYS, LOG_ERR, "Could not get hostname: %s\n", sockstrerror(sockerrno));
+                               return NULL;
+                       }
+                       hostname[HOST_NAME_MAX] = 0;
+                       envname = hostname;
+               }
+               ret_name = xstrdup(envname);
+               for (char *c = ret_name; *c; c++)
+                       if (!isalnum(*c))
+                               *c = '_';
+       } else {
+               ret_name = xstrdup(name);
+       }
+
+       if (!check_id(ret_name)) {
+               logger(DEBUG_ALWAYS, LOG_ERR, "Invalid name for myself!");
+               free(ret_name);
+               return NULL;
+       }
+
+       return ret_name;
+}