X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=gcrypt.c;h=1ae7cfb0deb4fb591dc97bcb5491b7cc54ec920a;hp=45a1c67d20da0b6d229180de92be10644a63d082;hb=d9f54f439c98aed8b974f55acd468bdae424683f;hpb=1a8e3628040a94a8c06027335962a6cb2f827a63

diff --git a/gcrypt.c b/gcrypt.c
index 45a1c67d..1ae7cfb0 100644
--- a/gcrypt.c
+++ b/gcrypt.c
@@ -15,6 +15,7 @@
 #include "crypt.h"
 #include "crypt_backend.h"
 #include "fd.h"
+#include "base64.h"
 
 //#define GCRYPT_DEBUG 1
 
@@ -212,7 +213,7 @@ static int decode_key(const char *key_file, const char *header_str,
 
 	ret = mmap_full_file(key_file, O_RDONLY, &map, &map_size, NULL);
 	if (ret < 0)
-		return ret;
+		goto out;
 	ret = -E_KEY_MARKER;
 	if (strncmp(map, header_str, strlen(header_str)))
 		goto unmap;
@@ -239,12 +240,11 @@ static int decode_key(const char *key_file, const char *header_str,
 		key[j++] = begin[i];
 	}
 	key[j] = '\0';
-	blob_size = key_size * 2;
-	blob = para_malloc(blob_size);
-	ret = base64_decode(key, blob, blob_size);
+	ret = base64_decode(key, j, (char **)&blob, &blob_size);
 	free(key);
 	if (ret < 0)
 		goto free_unmap;
+	ret = blob_size;
 	goto unmap;
 free_unmap:
 	free(blob);
@@ -257,6 +257,7 @@ unmap:
 		free(blob);
 		blob = NULL;
 	}
+out:
 	*result = blob;
 	return ret;
 }
@@ -300,64 +301,6 @@ static inline int get_long_form_num_length_bytes(unsigned char c)
 	return c & 0x7f;
 }
 
-static int find_pubkey_bignum_offset(const unsigned char *data, int len)
-{
-	const unsigned char *p = data, *end = data + len;
-
-	/* the whole thing starts with one sequence */
-	if (*p != ASN1_TYPE_SEQUENCE)
-		return -E_ASN1_PARSE;
-	p++;
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	if (is_short_form(*p))
-		p++;
-	else
-		p += 1 + get_long_form_num_length_bytes(*p);
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	/* another sequence containing the object id, skip it */
-	if (*p != ASN1_TYPE_SEQUENCE)
-		return -E_ASN1_PARSE;
-	p++;
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	if (!is_short_form(*p))
-		return -E_ASN1_PARSE;
-	p += 1 + get_short_form_length(*p);
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	/* all numbers are wrapped in a bit string object that follows */
-	if (*p != ASN1_TYPE_BIT_STRING)
-		return -E_ASN1_PARSE;
-	p++;
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	if (is_short_form(*p))
-		p++;
-	else
-		p += 1 + get_long_form_num_length_bytes(*p);
-	p++; /* skip number of unused bits in the bit string */
-	if (p >= end)
-		return -E_ASN1_PARSE;
-
-	/* next, we have a sequence of two integers (n and e) */
-	if (*p != ASN1_TYPE_SEQUENCE)
-		return -E_ASN1_PARSE;
-	p++;
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	if (is_short_form(*p))
-		p++;
-	else
-		p += 1 + get_long_form_num_length_bytes(*p);
-	if (p >= end)
-		return -E_ASN1_PARSE;
-	if (*p != ASN1_TYPE_INTEGER)
-		return -E_ASN1_PARSE;
-	return p - data;
-}
-
 /*
  * Returns: Number of bytes scanned. This may differ from the value returned via
  * bn_bytes because the latter does not include the ASN.1 prefix and a leading
@@ -387,7 +330,7 @@ static int read_bignum(unsigned char *start, unsigned char *end, gcry_mpi_t *bn,
 		for (i = 0; i < num_bytes; i++, cp++)
 			bn_size = (bn_size << 8) + *cp;
 	}
-	PARA_DEBUG_LOG("bn_size %d (0x%x)\n", bn_size, bn_size);
+	PARA_DEBUG_LOG("bn_size %d (0x%x)\n", bn_size, (unsigned)bn_size);
 	gret = gcry_mpi_scan(bn, GCRYMPI_FMT_STD, cp, bn_size, NULL);
 	if (gret) {
 		PARA_ERROR_LOG("%s while scanning n\n",
@@ -459,6 +402,7 @@ static int get_private_key(const char *key_file, struct asymmetric_key **result)
 	gcry_sexp_t sexp;
 	struct asymmetric_key *key;
 
+	*result = NULL;
 	ret = decode_key(key_file, PRIVATE_KEY_HEADER, PRIVATE_KEY_FOOTER,
 		&blob);
 	if (ret < 0)
@@ -537,65 +481,6 @@ free_blob:
 	return ret;
 }
 
-/** Public keys start with this header. */
-#define PUBLIC_KEY_HEADER "-----BEGIN PUBLIC KEY-----"
-/** Public keys end with this footer. */
-#define PUBLIC_KEY_FOOTER "-----END PUBLIC KEY-----"
-
-static int get_asn_public_key(const char *key_file, struct asymmetric_key **result)
-{
-	gcry_mpi_t n = NULL, e = NULL;
-	unsigned char *blob, *cp, *end;
-	int blob_size, ret, n_size;
-	gcry_error_t gret;
-	size_t erroff;
-	gcry_sexp_t sexp;
-	struct asymmetric_key *key;
-
-	ret = decode_key(key_file, PUBLIC_KEY_HEADER, PUBLIC_KEY_FOOTER,
-		&blob);
-	if (ret < 0)
-		return ret;
-	blob_size = ret;
-	end = blob + blob_size;
-	ret = find_pubkey_bignum_offset(blob, blob_size);
-	if (ret < 0)
-		goto free_blob;
-	PARA_DEBUG_LOG("decoding public RSA params at offset %d\n", ret);
-	cp = blob + ret;
-
-	ret = read_bignum(cp, end, &n, &n_size);
-	if (ret < 0)
-		goto free_blob;
-	cp += ret;
-
-	ret = read_bignum(cp, end, &e, NULL);
-	if (ret < 0)
-		goto release_n;
-
-	gret = gcry_sexp_build(&sexp, &erroff, RSA_PUBKEY_SEXP, n, e);
-	if (gret) {
-		PARA_ERROR_LOG("offset %zu: %s\n", erroff,
-			gcry_strerror(gcry_err_code(gret)));
-		ret = -E_SEXP_BUILD;
-		goto release_e;
-	}
-	key = para_malloc(sizeof(*key));
-	key->sexp = sexp;
-	key->num_bytes = n_size;
-	*result = key;
-	ret = n_size;
-	PARA_INFO_LOG("successfully read %u bit asn public key\n", n_size * 8);
-
-release_e:
-	gcry_mpi_release(e);
-release_n:
-	gcry_mpi_release(n);
-free_blob:
-	free(blob);
-	return ret;
-}
-
 static int get_ssh_public_key(unsigned char *data, int size, gcry_sexp_t *result)
 {
 	int ret;
@@ -605,13 +490,9 @@ static int get_ssh_public_key(unsigned char *data, int size, gcry_sexp_t *result
 	gcry_mpi_t e = NULL, n = NULL;
 
 	PARA_DEBUG_LOG("decoding %d byte public rsa-ssh key\n", size);
-	if (size > INT_MAX / 4)
-		return -ERRNO_TO_PARA_ERROR(EOVERFLOW);
-	blob = para_malloc(2 * size);
-	ret = uudecode((char *)data, blob, 2 * size);
+	ret = uudecode((char *)data, size, (char **)&blob, &decoded_size);
 	if (ret < 0)
 		goto free_blob;
-	decoded_size = ret;
 	end = blob + decoded_size;
 	dump_buffer("decoded key", blob, decoded_size);
 	ret = check_ssh_key_header(blob, decoded_size);
@@ -651,7 +532,7 @@ static int get_ssh_public_key(unsigned char *data, int size, gcry_sexp_t *result
 		goto release_n;
 	}
 	ret = nr_scanned / 32 * 32;
-	PARA_INFO_LOG("successfully read %u bit ssh public key\n", ret * 8);
+	PARA_INFO_LOG("successfully read %d bit ssh public key\n", ret * 8);
 release_n:
 	gcry_mpi_release(n);
 release_e:
@@ -661,8 +542,7 @@ free_blob:
 	return ret;
 }
 
-int get_asymmetric_key(const char *key_file, int private,
-		struct asymmetric_key **result)
+int get_public_key(const char *key_file, struct asymmetric_key **result)
 {
 	int ret, ret2;
 	void *map;
@@ -671,17 +551,13 @@ int get_asymmetric_key(const char *key_file, int private,
 	gcry_sexp_t sexp;
 	struct asymmetric_key *key;
 
-	if (private)
-		return get_private_key(key_file, result);
 	ret = mmap_full_file(key_file, O_RDONLY, &map, &map_size, NULL);
 	if (ret < 0)
 		return ret;
 	ret = is_ssh_rsa_key(map, map_size);
 	if (!ret) {
-		ret = para_munmap(map, map_size);
-		if (ret < 0)
-			return ret;
-		return get_asn_public_key(key_file, result);
+		para_munmap(map, map_size);
+		return -E_SSH_PARSE;
 	}
 	start = map + ret;
 	end = map + map_size;
@@ -702,7 +578,7 @@ unmap:
 	return ret;
 }
 
-void free_asymmetric_key(struct asymmetric_key *key)
+void free_public_key(struct asymmetric_key *key)
 {
 	if (!key)
 		return;
@@ -781,6 +657,9 @@ int priv_decrypt(const char *key_file, unsigned char *outbuf,
 	gcry_sexp_t in, out, priv_key;
 	size_t nbytes;
 
+	ret = check_private_key_file(key_file);
+	if (ret < 0)
+		return ret;
 	PARA_INFO_LOG("decrypting %d byte input\n", inlen);
 	/* key_file -> asymmetric key priv */
 	ret = get_private_key(key_file, &priv);
@@ -831,7 +710,8 @@ in_mpi_release:
 key_release:
 	gcry_sexp_release(priv_key);
 free_key:
-	free_asymmetric_key(priv);
+	gcry_sexp_release(priv->sexp);
+	free(priv);
 	return ret;
 }