Objective-CのFTPファイル送受信で日本語名ファイルを扱う ref: http://qiita.com/t_oginogin/items/6ed62df0db6c7034bc49

file1.m

- (void)requestsManager:(id<GRRequestsManagerProtocol>)requestsManager didCompleteListingRequest:(id<GRRequestProtocol>)request listing:(NSArray *)listing
{
    NSLog(@"requestsManager:didCompleteListingRequest:listing: \n%@", listing);

    self.fileLists = nil;
    self.fileLists = [[NSMutableArray alloc] init];

    // 日本語ファイル名の変換
    NSString *name;
    NSData *nameData;
    NSString *newName;
    for (int i = 0; i<[listing count]; i++) {
        name = listing[i];
        nameData = [name dataUsingEncoding:NSMacOSRomanStringEncoding];
        if (nameData != nil) {
            newName = [[NSString alloc] initWithData:nameData encoding:NSShiftJISStringEncoding];
            [self.fileLists addObject:newName];
        }
    }

    self.getButton.enabled = YES;
    [self.fileListView reloadData];
}

file2.m

- (IBAction)getFile:(id)sender {
    [self _setupManager];

    if (self.ftpFileName == nil) {
        return;
    }

    NSData *nameData = [self.ftpFileName dataUsingEncoding:NSShiftJISStringEncoding];
    if (nameData == nil) {
        return;
    }

    NSString *newName = [[NSString alloc] initWithData:nameData encoding:NSMacOSRomanStringEncoding];
    NSString* encodedFileName = [newName stringByAddingPercentEscapesUsingEncoding:NSMacOSRomanStringEncoding];

    [self.requestsManager addRequestForDownloadFileAtRemotePath:encodedFileName toLocalPath:[NSTemporaryDirectory() stringByAppendingPathComponent:self.ftpFileName]];
    [self.requestsManager startProcessingRequests];
}

file3.m

- (IBAction)putFile:(id)sender {
    [self _setupManager];

    NSData *nameData = [self.ftpFileName dataUsingEncoding:NSShiftJISStringEncoding];
    if (nameData == nil) {
        return;
    }

    NSString *newName = [[NSString alloc] initWithData:nameData encoding:NSMacOSRomanStringEncoding];
    NSString* encodedFileName = [newName stringByAddingPercentEscapesUsingEncoding:NSMacOSRomanStringEncoding];

    [self.requestsManager addRequestForUploadFileAtLocalPath:[NSTemporaryDirectory() stringByAppendingPathComponent:self.ftpFileName] toRemotePath:encodedFileName];
    [self.requestsManager startProcessingRequests];
}

file4.m

- (IBAction)getFile:(id)sender {
    [self _setupManager];

    if (self.ftpFileName == nil) {
        return;
    }

    NSData *nameData = [self.ftpFileName dataUsingEncoding:NSShiftJISStringEncoding];
    if (nameData == nil) {
        return;
    }

    NSString *fileName = [[NSString alloc] initWithData:nameData encoding:NSMacOSRomanStringEncoding];

    [self.requestsManager addRequestForDownloadFileAtRemotePath:fileName toLocalPath:[NSTemporaryDirectory() stringByAppendingPathComponent:self.ftpFileName]];
    [self.requestsManager startProcessingRequests];
}

file5.m

- (IBAction)putFile:(id)sender {
    [self _setupManager];

    NSData *nameData = [self.ftpFileName dataUsingEncoding:NSShiftJISStringEncoding];
    if (nameData == nil) {
        return;
    }

    NSString *fileName = [[NSString alloc] initWithData:nameData encoding:NSMacOSRomanStringEncoding];

    [self.requestsManager addRequestForUploadFileAtLocalPath:[NSTemporaryDirectory() stringByAppendingPathComponent:self.ftpFileName] toRemotePath:fileName];
    [self.requestsManager startProcessingRequests];
}

GRRequest+encode.h

#import "GRRequest.h"

@interface GRRequest(Encode)
@end

GRRequest+encode.m

#import "GRRequest+encode.h"
#import <objc/runtime.h>

@implementation GRRequest(Encode)

- (NSString *)encodeString:(NSString *)string;
{
    NSString *urlEncoded = (__bridge_transfer NSString *)CFURLCreateStringByAddingPercentEscapes(
                                                                                                 NULL,
                                                                                                 (__bridge CFStringRef) string,
                                                                                                 NULL,
                                                                                                 (CFStringRef)@"!*'\"();:@&=+$,?%#[]% ",
                                                                                                 kCFStringEncodingMacRoman);
    return urlEncoded;
}

@end

PodFile

pod "GoldRaccoon"