Initial import

.gitignore

@@ -0,0 +1,54 @@
+pwhash
+# Ignore patterns for C
+# Prerequisites
+*.d
+
+# Object files
+*.o
+*.ko
+*.obj
+*.elf
+
+# Linker output
+*.ilk
+*.map
+*.exp
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Libraries
+*.lib
+*.a
+*.la
+*.lo
+
+# Shared objects (inc. Windows DLLs)
+*.dll
+*.so
+*.so.*
+*.dylib
+
+# Executables
+*.exe
+*.out
+*.app
+*.i*86
+*.x86_64
+*.hex
+
+# Debug files
+*.dSYM/
+*.su
+*.idb
+*.pdb
+
+# Kernel Module Compile Results
+*.mod*
+*.cmd
+.tmp_versions/
+modules.order
+Module.symvers
+Mkfile.old
+dkms.conf

Makefile

@@ -0,0 +1,3 @@
+LDFLAGS = -lcrypt
+
+all: pwhash

pwhash.c

@@ -0,0 +1,107 @@
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <string.h>
+#include <termios.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+static const struct option options[] = {
+	{"method", required_argument, NULL, 'm'},
+	{"rounds", required_argument, NULL, 'r'},
+	{0, 0, 0, 0}
+};
+static const char *optstring = "m:r:";
+
+static const char charset[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789./";
+
+static char *name;
+
+void usage(void)
+{
+	fprintf(stderr, "Usage: %s [(-m|--method) METHOD] [(-r|--rounds) ROUNDS]\n", name);
+	fprintf(stderr, "See crypt(3) for possible values of METHOD and ROUNDS.\n");
+	exit(1);
+}
+
+int main(int argc, char *argv[]) {
+	name = argv[0];
+	char *method = NULL;
+	char *rounds = NULL;
+	int ch;
+	while ((ch = getopt_long(argc, argv, optstring, options, NULL)) != -1) {
+		switch (ch) {
+		case 'm':
+			method = strdup(optarg);
+			break;
+		case 'r':
+			rounds = strdup(optarg);
+			break;
+		default:
+			usage();
+		}
+	}
+
+        char salt[17] = {0};
+	int urandom = open("/dev/urandom", O_RDONLY);
+	if (urandom == -1) {
+		fprintf(stderr, "Couldn't open /dev/urandom!\n");
+		exit(1);
+	}
+	unsigned char buf;
+	char *p = salt;
+	for (int i = 0; i < 16; i++) {
+		if (read(urandom, &buf, 1) != 1) {
+			fprintf(stderr, "Couldn't read from /dev/urandom!\n");
+			exit(1);
+		}
+		*p = charset[buf % (sizeof(charset) - 1)];
+		p++;
+	}
+
+	char *crypt_salt = NULL;
+        if (!method) {
+		crypt_salt = salt;
+	} else {
+		if (rounds) {
+			asprintf(&crypt_salt, "$%s$rounds=%s$%s$", method, rounds, salt);
+		} else {
+			asprintf(&crypt_salt, "$%s$%s$", method, salt);
+		}
+		if (!crypt_salt) {
+			exit(1);
+		}
+	}
+
+	printf("Password: ");
+	fflush(stdout);
+	struct termios t;
+	tcgetattr(0, &t);
+	t.c_lflag &= ~ECHO;
+	tcsetattr(0, TCSADRAIN, &t);
+	char *key = NULL;
+	size_t key_len = 0;
+	ssize_t len = getline(&key, &key_len, stdin);
+	t.c_lflag |= ECHO;
+	tcsetattr(0, TCSANOW, &t);
+
+	printf("\n");
+	if (len <= 1) {
+		fprintf(stderr, "Password is empty!\n");
+		exit(1);
+	}
+	if (key[len - 1] == '\n') {
+		key[len - 1] = '\0';
+	}
+
+	char *hash = crypt(key, crypt_salt);
+	if (hash) {
+		printf("%s\n", hash);
+		exit(0);
+	}
+	return 1;
+}