RSA_private_decrypt失败

我用openssl。 首先我创建了私钥/公钥，然后我加密了一个字符串并将结果保存在一个文件中。 当我尝试解密文件时，我的程序失败了。 更重要的是，每次加密文件都不同（我使用md5sum检查）。 我错过了什么？

/* gcc -lssl queation.c -o test_ssl #openssl genrsa -out test_private.key 1024 #openssl rsa -in test_private.key -pubout -out test_public.key */ #include #include #include #include #include #include #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #include  #define OPENSSLKEY "test_private.key" #define PUBLICKEY "test_public.key" #define BUFFSIZE 1024 #define SIZE 1024 #define LIC_FILE "lic.rn" #define PRTFL printf("fun = %s, line = %d\n", __FUNCTION__,__LINE__) static char *ptr_en; static char *p_en; static RSA *p_rsa_public; static FILE *fp_public; static int flen_public, rsa_public_len; static char *ptr_de; static char *p_de; static RSA *p_rsa_private; static FILE *fp_private; static int flen_private, rsa_private_len; void usage( unsigned char * prog_name) { printf("usage: %s\n", prog_name); exit(1); } int main(int argc , char ** argv) { int i, ret , len; unsigned char buf_plain[32]; unsigned char *buf_en; unsigned char *raw_buffer; FILE * pf_tmp; if( argc != 1) { usage(argv[0]); } snprintf(buf_plain,sizeof(buf_plain),"this is a test line.\n"); if((fp_public=fopen(PUBLICKEY,"r"))==NULL) { perror("open public key file error"); ret = -1; goto error; } if((p_rsa_public = PEM_read_RSA_PUBKEY(fp_public,NULL,NULL,NULL))==NULL) { ERR_print_errors_fp(stdout); ret = -1; goto error; } rsa_public_len=RSA_size(p_rsa_public); p_en=(unsigned char *)malloc(rsa_public_len+1); memset(p_en,0,rsa_public_len+1); //printf("%s(%d)p_en = %p,rsa_public_len = %d\n", __FUNCTION__,__LINE__,p_en,rsa_public_len); len = RSA_public_encrypt(rsa_public_len,buf_plain,p_en,p_rsa_public,RSA_NO_PADDING); if (len !=rsa_public_len) { fprintf(stderr,"Error: len =%d, rsa_public_len = %d,ciphertext should match length of key\n", len,rsa_public_len); ret = -1; goto error; } pf_tmp = fopen(LIC_FILE,"w"); if( NULL == pf_tmp ) { printf("open %s failed\n",LIC_FILE); ret = -1; goto error; } fwrite(p_en,1,128,pf_tmp); fclose(pf_tmp); if((fp_private=fopen(OPENSSLKEY,"r"))==NULL) { perror("open private key file error"); ret = -1; goto error; } if((p_rsa_private=PEM_read_RSAPrivateKey(fp_private,NULL,NULL,NULL))==NULL) { ERR_print_errors_fp(stdout); ret = -1; goto error; } rsa_private_len = RSA_size(p_rsa_private); pf_tmp = fopen(LIC_FILE,"r"); if( NULL == pf_tmp ) { printf("open %s failed\n",LIC_FILE); ret = -1; goto error2; } raw_buffer = calloc(rsa_private_len,sizeof(char)); if( NULL == raw_buffer ) { ret = -1; goto error; } len = fread(raw_buffer, sizeof(char),sizeof(raw_buffer), pf_tmp); if( len <=0 ) { ret = -1; goto error; } p_de=(unsigned char *)malloc(rsa_private_len+1); memset(p_de,0,rsa_private_len+1); //printf("%s(%d)p_en = %p,rsa_public_len = %d\n", __FUNCTION__,__LINE__,p_en,rsa_public_len); len =RSA_private_decrypt (rsa_private_len,raw_buffer,p_de,p_rsa_private,RSA_NO_PADDING); printf("%s(%d) p_de = %s\n",__FUNCTION__,__LINE__,p_de); if ( len != rsa_private_len ) { fprintf(stderr,"Error: ciphertext should match length of key\n"); exit(1); } error2: fclose(pf_tmp); error: free(ptr_en); free(ptr_de); fclose(fp_public); fclose(fp_private); RSA_free(p_rsa_public); RSA_free(p_rsa_private); return ret; } 

Answer 1

看起来你没有读完整个文件：

 len = fread(raw_buffer, sizeof(char),sizeof(raw_buffer), pf_tmp); 

请注意， sizeof(raw_buffer)是指针的大小，但是您在文件中写入了128个字节（1024位）。 所以你只读回4或8个字节并试图解密它。

尝试回读128个字节。