Add libar2simplified_decode_r

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 11 insertions, 177 deletions

diff --git a/libar2simplified_decode.c b/libar2simplified_decode.c
index 2c2f38e..eb3d3ee 100644
--- a/libar2simplified_decode.c
+++ b/libar2simplified_decode.c
@@ -1,194 +1,28 @@
 /* See LICENSE file for copyright and license details. */
 #include "common.h"
-#ifdef __linux__
-#include <sys/random.h>
-#endif
-#include <time.h>
 
 
-static size_t
-decode_u32(const char *s, uint_least32_t *outp)
-{
-	uint_least32_t digit;
-	size_t i;
-
-	if ((s[0] == '0' && s[1] == '0') || !isdigit(s[0])) {
-		errno = EINVAL;
-		return 0;
-	}
-
-	*outp = 0;
-	for (i = 0; isdigit(s[i]); i++) {
-		digit = (uint_least32_t)(s[i] & 15);
-		if (*outp > ((uint_least32_t)0xFFFFffffUL - digit) / 10) {
-			errno = ERANGE;
-			return 0;
-		}
-		*outp = *outp * 10 + digit;
-	}
-
-	return i;
-}
+union function {
+	int (*func)(char *out, size_t n);
+};
 
 
 static int
-random_salt(char *out, size_t n, int (*random_byte_generator)(char *out, size_t n))
-{
-#define ALPHABET "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
-	static int srand_called = 0;
-
-	double x;
-	size_t i;
-	int xi;
-#ifdef __linux__
-	ssize_t r;
-#endif
-
-	if (random_byte_generator) {
-		if (random_byte_generator(out, n))
-			return -1;
-	} else {
-		i = 0;
-#ifdef __linux__
-		for(; i < n; i += (size_t)r) {
-			r = getrandom(&out[i], n - i, GRND_NONBLOCK);
-			if(r < 0)
-				break;
-		}
-#endif
-		if (!srand_called) {
-			srand((unsigned int)time(NULL) ^ (unsigned int)rand());
-			srand_called = 1;
-		}
-		for(; i < n; i++) {
-			xi = rand();
-			x = (double)xi;
-			x /= (double)RAND_MAX;
-			x *= 63;
-			out[i] = (char)x;
-		}
-	}
-
-	for (i = 0; i < n; i++)
-		out[i] = ALPHABET[out[i] % 64];
-	return 0;
-}
-
-
-static void *
-allocate(size_t num, size_t size, size_t alignment, struct libar2_context *ctx)
-{
-	(void) ctx;
-	(void) alignment;
-	return malloc(num * size);
-}
-
-
-static void
-deallocate(void *ptr, struct libar2_context *ctx)
+function_wrapper(char *out, size_t n, void *function)
 {
-	(void) ctx;
-	free(ptr);
+	union function *func = function;
+	return func->func(out, n);
 }
 
 
 struct libar2_argon2_parameters *
 libar2simplified_decode(const char *str, char **tagp, char **endp, int (*random_byte_generator)(char *out, size_t n))
 {
-	struct libar2_argon2_parameters params, *ret;
-	const char *p = str;
-	const char *end;
-	char *str_free = NULL;
-	char *buf = NULL;
-	size_t n, saltsize, offset;
-	uint_least32_t saltlen, hashlen;
-	struct libar2_context ctx;
-
-	if (*p != '$')
-		goto einval;
-	p = strchr(&p[1], '$');
-	if (!p)
-		goto einval;
-	if (p[1] == 'v' && p[2] == '=') {
-		p = strchr(&p[1], '$');
-		if (!p)
-			goto einval;
-	}
-	p = strchr(&p[1], '$');
-	if (!p)
-		goto einval;
-	p++;
-	end = strchr(p, '$');
-	if (!end)
-		goto einval;
-
-	if (*p == '*') {
-		n = decode_u32(&p[1], &saltlen);
-		if (!n++)
-			goto fail;
-		if (&p[n] != end)
-			goto einval;
-		params.saltlen = (size_t)saltlen;
-		saltsize = libar2_encode_base64(NULL, NULL, saltlen) - 1;
-		offset = (size_t)(p - str);
-		str_free = malloc(offset + saltsize + strlen(&p[n]) + 1);
-		if (!str_free)
-			goto enomem;
-		memcpy(str_free, str, offset);
-		if (random_salt(&str_free[offset], saltsize, random_byte_generator))
-			goto fail;
-		offset += saltsize;
-		stpcpy(&str_free[offset], &p[n]);
-		str = str_free;
-	}
-	end++;
-
-	ctx.allocate = allocate;
-	ctx.deallocate = deallocate;
-
-	if (!libar2_decode_params(str, &params, &buf, &ctx))
-		goto fail;
-
-	if (*end == '*') {
-		n = decode_u32(&end[1], &hashlen);
-		if (!n++)
-			goto fail;
-		end = &end[n];
-		params.hashlen = (size_t)hashlen;
-		if (tagp)
-			*tagp = NULL;
+	union function func;
+	if (random_byte_generator) {
+		func.func = random_byte_generator;
+		return libar2simplified_decode_r(str, tagp, endp, function_wrapper, &func);
 	} else {
-		if (tagp)
-			*tagp = *(void **)(void *)&end;
-		end = &end[libar2_encode_base64(NULL, NULL, params.hashlen) - 1];
+		return libar2simplified_decode_r(str, tagp, endp, NULL, NULL);
 	}
-
-	ret = malloc(sizeof(params) + params.saltlen);
-	if (!ret)
-		goto enomem;
-	memcpy(ret, &params, sizeof(params));
-	if (buf) {
-		memcpy(&((char *)ret)[sizeof(params)], buf, params.saltlen);
-		ret->salt = &((unsigned char *)ret)[sizeof(params)];
-		deallocate(buf, &ctx);
-	}
-
-	if (endp)
-		*endp = *(void **)(void *)&end;
-
-	free(str_free);
-	return ret;
-
-einval:
-	errno = EINVAL;
-	return NULL;
-
-fail:
-	free(str_free);
-	return NULL;
-
-enomem:
-	free(str_free);
-	errno = ENOMEM;
-	return NULL;
 }