RSA作爲最主流的加解密與驗籤算法,iOS當然少不了
簽名
unsigned char *rsaPKCS1SignData(const unsigned char *src,int src_len,unsigned char*pri_key,int pri_key_len, int *dst_len) { unsigned char *pri_pem = formatPem(pri_key, PEM_FORMAT_PRIVATEKEY); BIO *bio_private = NULL; RSA *rsa_private = NULL; bio_private = BIO_new(BIO_s_mem()); BIO_write(bio_private, pri_pem, strlen((const char *)pri_pem)); unsigned char pwd[] = ""; rsa_private = PEM_read_bio_RSAPrivateKey(bio_private, NULL, (pem_password_cb *)pwd,NULL); EVP_PKEY *key = EVP_PKEY_new(); int err = EVP_PKEY_assign_RSA(key,rsa_private); int size=0; if (err) { size = EVP_PKEY_size(key); } EVP_MD_CTX *ctx = EVP_MD_CTX_create(); EVP_MD_CTX_init(ctx); EVP_SignInit_ex(ctx,EVP_sha1() , NULL); EVP_SignUpdate(ctx, src,src_len); unsigned char *md=(unsigned char *)malloc(size); unsigned int len = 0; EVP_SignFinal(ctx, md, &len, key); *dst_len = len; EVP_PKEY_free(key); EVP_MD_CTX_cleanup(ctx); return md; }
驗籤
bool rsaVerify(const unsigned char *src,int src_len,unsigned char *sig,unsigned int sigl_len,unsigned char *pub_key,int pub_key_len) { unsigned char *pub_pem = formatPem(pub_key, PEM_FORMAT_PUBKEY); BIO *bio_public = NULL; bio_public = BIO_new(BIO_s_mem()); BIO_write(bio_public, pub_pem, strlen((const char *)pub_pem)); EVP_PKEY *key=NULL; PEM_read_bio_PUBKEY(bio_public, &key, NULL, NULL); int size=0; if (key) { size = EVP_PKEY_size(key); } EVP_MD_CTX *ctx = EVP_MD_CTX_create(); EVP_MD_CTX_init(ctx); EVP_VerifyInit_ex(ctx, EVP_sha1(), NULL); EVP_VerifyUpdate(ctx, src,src_len); int suc = EVP_VerifyFinal(ctx, sig, sigl_len, key); EVP_PKEY_free(key); EVP_MD_CTX_cleanup(ctx); if (suc == 1) { return true; } else return false; }