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Objective-C

Convert PuTTY Private Key (ppk) to OpenSSH (pem)

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Convert a PuTTY format private key file (.ppk) to OpenSSH (.pem).

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Objective-C
#import <CkoSshKey.h>
#import <NSString.h>

BOOL success = NO;

CkoSshKey *key = [[CkoSshKey alloc] init];

// Load an unencrypted or encrypted PuTTY private key.

// If  your PuTTY private key is encrypted, set the Password
// property before calling FromPuttyPrivateKey.
// If your PuTTY private key is not encrypted, it makes no diffference
// if Password is set or not set.
key.Password = @"secret";

// First load the .ppk file into a string:
NSString *keyStr = 0;
keyStr = [key LoadText: @"putty_private_key.ppk"];

// Import into the SSH key object:
success = [key FromPuttyPrivateKey: keyStr];
if (success != YES) {
    NSLog(@"%@",key.LastErrorText);
    return;
}

// Convert to an encrypted or unencrypted OpenSSH key.

// First demonstrate converting to an unencrypted OpenSSH key
NSString *unencryptedKeyStr = 0;
BOOL bEncrypt = NO;
unencryptedKeyStr = [key ToOpenSshPrivateKey: bEncrypt];
success = [key SaveText: unencryptedKeyStr path: @"unencrypted_openssh.pem"];
if (success != YES) {
    NSLog(@"%@",key.LastErrorText);
    return;
}

// Save to an encrypted OpenSSH PEM file:
NSString *encryptedKeyStr = 0;
bEncrypt = YES;
key.Password = @"myPassword";
encryptedKeyStr = [key ToOpenSshPrivateKey: bEncrypt];
success = [key SaveText: encryptedKeyStr path: @"encrypted_openssh.pem"];
if (success != YES) {
    NSLog(@"%@",key.LastErrorText);
    return;
}

NSLog(@"%@",@"Done!");