Convert openssh key to putty key in batch mode I'm writing a Perl script to convert Openssh DSA public key to Putty format. There's a C code does similar thing but only for RSA key. I got problem when creating hmac hash. I don't know much C and want to use Perl to do the same thing as followig C routine does. Can anyone helps? Thanks. source http://www.anchor.net.au/code/openssh2putty.c // binary strings with 4 octet length header when dumped typedef struct {     int length;     unsigned char data[1]; } bstring; bstring * asciiz_to_bstring(const char *s) { unsigned l; bstring *b; l = strlen(s); b = (bstring *)xmalloc(4 + l); b->;length = l; memcpy(&b->;data, s, l); return b; } Convert openssh key to putty key in batch mode unsigned l; bstring *b; l = strlen(s);       求出傳入字符串的長度 b = (bstring *)xmalloc(4 + l);    分配一塊內存  siseof(int)=4  sizeof(char)=1       b->;length = l;   結構體的一field放長度 memcpy(&b->;data, s, l);  結構體的另一field存傳入的字符串 return b;   返回剛才申請的那快內存 Convert openssh key to putty key in batch mode Thanks for all the reply. I didn't get my Perl script to work. But I found a modified source code which supports DSA key. It works fine after I removed the private key encryption part. I post the source code here just in case someone want to convert openssh key to PuTTY format in batch mode.   How to compile 1. Download openssh-3.4p1 source code 2. put the openssh2putty.c under openssh-3.4p1 3. Modify the Configure.in and copy the lines with ssh-add and change ssh-add to openssh2putty 4. ./configure 5. make openssh2putty [ 關閉窗口 ]