Mercurial > dropbear
view libtomcrypt/demos/constants.c @ 1861:2b3a8026a6ce
Add re-exec for server
This allows ASLR to re-randomize the address
space for every connection, preventing some
vulnerabilities from being exploitable by
repeated probing.
Overhead (memory and time) is yet to be confirmed.
At present this is only enabled on Linux. Other BSD platforms
with fexecve() would probably also work though have not been tested.
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Sun, 30 Jan 2022 10:14:56 +0800 |
parents | e9dba7abd939 |
children |
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/* LibTomCrypt, modular cryptographic library -- Tom St Denis * * LibTomCrypt is a library that provides various cryptographic * algorithms in a highly modular and flexible manner. * * The library is free for all purposes without any express * guarantee it works. */ #include "tomcrypt.h" #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L #include <libgen.h> #else #define basename(x) x #endif /** @file demo_crypt_constants.c Demo how to get various constants to dynamic languages like Python Larry Bugbee, February 2013 */ static void _print_line(const char* cmd, const char* desc) { printf(" %-16s - %s\n", cmd, desc); } int main(int argc, char **argv) { if (argc == 1) { /* given a specific constant name, get and print its value */ char name[] = "CTR_COUNTER_BIG_ENDIAN"; int value; char *names_list; unsigned int names_list_len; if (crypt_get_constant(name, &value) != 0) exit(EXIT_FAILURE); printf("\n %s is %d \n\n", name, value); /* get and print the length of the names (and values) list */ if (crypt_list_all_constants(NULL, &names_list_len) != 0) exit(EXIT_FAILURE); printf(" need to allocate %u bytes \n\n", names_list_len); /* get and print the names (and values) list */ if ((names_list = malloc(names_list_len)) == NULL) exit(EXIT_FAILURE); if (crypt_list_all_constants(names_list, &names_list_len) != 0) exit(EXIT_FAILURE); printf(" supported constants:\n\n%s\n\n", names_list); free(names_list); } else if (argc == 2) { if (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0) { char* base = strdup(basename(argv[0])); printf("Usage: %s [-a] [-s name]\n\n", base); _print_line("<no argument>", "The old behavior of the demo"); _print_line("-a", "Only lists all constants"); _print_line("-s name", "List a single constant given as argument"); _print_line("-h", "The help you're looking at"); free(base); } else if (strcmp(argv[1], "-a") == 0) { char *names_list; unsigned int names_list_len; /* get and print the length of the names (and values) list */ if (crypt_list_all_constants(NULL, &names_list_len) != 0) exit(EXIT_FAILURE); /* get and print the names (and values) list */ if ((names_list = malloc(names_list_len)) == NULL) exit(EXIT_FAILURE); if (crypt_list_all_constants(names_list, &names_list_len) != 0) exit(EXIT_FAILURE); printf("%s\n", names_list); free(names_list); } } else if (argc == 3) { if (strcmp(argv[1], "-s") == 0) { int value; if (crypt_get_constant(argv[2], &value) != 0) exit(EXIT_FAILURE); printf("%s,%u\n", argv[2], value); } } return 0; } /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */