X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=rsa.c;h=d5d80ff6664dbcb0e0a1d0a07960c67fb3bcbf92;hb=934cb196c3928724c351045f25c740a830941e4a;hp=cda8d8924dfac0f4bd68a54d8648d8ec6fa670f6;hpb=4b9f8efbb918eb573f8b4b0289aa0349a4e68f4c;p=secnet.git

diff --git a/rsa.c b/rsa.c
index cda8d89..d5d80ff 100644
--- a/rsa.c
+++ b/rsa.c
@@ -332,6 +332,7 @@ struct rsapriv_load_ctx {
     void (*verror)(struct rsapriv_load_ctx *l,
 		   FILE *maybe_f, bool_t unsup,
 		   const char *message, va_list args);
+    bool_t (*postreadcheck)(struct rsapriv_load_ctx *l, FILE *f);
     union {
 	struct {
 	    struct cloc loc;
@@ -344,24 +345,27 @@ struct rsapriv_load_ctx {
 #define LDFATAL_FILE(...) ({ load_error(l,f,0,__VA_ARGS__); goto error_out; })
 #define LDUNSUP_FILE(...) ({ load_error(l,f,1,__VA_ARGS__); goto error_out; })
 #define FREE(b)                ({ free((b)); (b)=0; })
+#define KEYFILE_GET(is)   ({					\
+	uint##is##_t keyfile_get_tmp=keyfile_get_##is(l,f);	\
+	if (!l->postreadcheck(l,f)) goto error_out;		\
+	keyfile_get_tmp;					\
+    })
 
-static uint32_t keyfile_get_int(struct cloc loc, FILE *f)
+static uint32_t keyfile_get_32(struct rsapriv_load_ctx *l, FILE *f)
 {
     uint32_t r;
     r=fgetc(f)<<24;
     r|=fgetc(f)<<16;
     r|=fgetc(f)<<8;
     r|=fgetc(f);
-    cfgfile_postreadcheck(loc,f);
     return r;
 }
 
-static uint16_t keyfile_get_short(struct cloc loc, FILE *f)
+static uint16_t keyfile_get_16(struct rsapriv_load_ctx *l, FILE *f)
 {
     uint16_t r;
     r=fgetc(f)<<8;
     r|=fgetc(f);
-    cfgfile_postreadcheck(loc,f);
     return r;
 }
 
@@ -387,8 +391,7 @@ static void rsapriv_dispose(void *sst)
 
 static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
 					 FILE *f, struct cloc loc,
-					 bool_t do_validity_check,
-					 const char *filename)
+					 bool_t do_validity_check)
 {
     struct rsapriv *st=0;
     long length;
@@ -433,20 +436,19 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     b=safe_malloc(length,"rsapriv_apply");
     if (fread(b,length,1,f)!=1 || memcmp(b,AUTHFILE_ID_STRING,length)!=0) {
 	LDUNSUP_FILE("failed to read magic ID"
-			   " string from SSH1 private keyfile \"%s\"\n",
-			   filename);
+		     " string from SSH1 private keyfile\n");
     }
     FREE(b);
 
     cipher_type=fgetc(f);
-    keyfile_get_int(loc,f); /* "Reserved data" */
+    KEYFILE_GET(32); /* "Reserved data" */
     if (cipher_type != 0) {
 	LDUNSUP("we don't support encrypted keyfiles\n");
     }
 
     /* Read the public key */
-    keyfile_get_int(loc,f); /* Not sure what this is */
-    length=(keyfile_get_short(loc,f)+7)/8;
+    KEYFILE_GET(32); /* Not sure what this is */
+    length=(KEYFILE_GET(16)+7)/8;
     if (length>RSA_MAX_MODBYTES) {
 	LDFATAL("implausible length %ld for modulus\n",
 		 length);
@@ -457,7 +459,7 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     }
     read_mpbin(&st->n,b,length);
     FREE(b);
-    length=(keyfile_get_short(loc,f)+7)/8;
+    length=(KEYFILE_GET(16)+7)/8;
     if (length>RSA_MAX_MODBYTES) {
 	LDFATAL("implausible length %ld for e\n",length);
     }
@@ -468,7 +470,7 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     read_mpbin(&e,b,length);
     FREE(b);
     
-    length=keyfile_get_int(loc,f);
+    length=KEYFILE_GET(32);
     if (length>1024) {
 	LDFATAL("implausibly long (%ld) key comment\n",
 		 length);
@@ -482,12 +484,12 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     /* Check that the next two pairs of characters are identical - the
        keyfile is not encrypted, so they should be */
 
-    if (keyfile_get_short(loc,f) != keyfile_get_short(loc,f)) {
+    if (KEYFILE_GET(16) != KEYFILE_GET(16)) {
 	LDFATAL("corrupt keyfile\n");
     }
 
     /* Read d */
-    length=(keyfile_get_short(loc,f)+7)/8;
+    length=(KEYFILE_GET(16)+7)/8;
     if (length>RSA_MAX_MODBYTES) {
 	LDFATAL("implausibly long (%ld) decryption key\n",
 		 length);
@@ -499,7 +501,7 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     read_mpbin(&d,b,length);
     FREE(b);
     /* Read iqmp (inverse of q mod p) */
-    length=(keyfile_get_short(loc,f)+7)/8;
+    length=(KEYFILE_GET(16)+7)/8;
     if (length>RSA_MAX_MODBYTES) {
 	LDFATAL("implausibly long (%ld)"
 		 " iqmp auxiliary value\n", length);
@@ -511,7 +513,7 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     read_mpbin(&iqmp,b,length);
     FREE(b);
     /* Read q (the smaller of the two primes) */
-    length=(keyfile_get_short(loc,f)+7)/8;
+    length=(KEYFILE_GET(16)+7)/8;
     if (length>RSA_MAX_MODBYTES) {
 	LDFATAL("implausibly long (%ld) q value\n",
 		 length);
@@ -523,7 +525,7 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     read_mpbin(&st->q,b,length);
     FREE(b);
     /* Read p (the larger of the two primes) */
-    length=(keyfile_get_short(loc,f)+7)/8;
+    length=(KEYFILE_GET(16)+7)/8;
     if (length>RSA_MAX_MODBYTES) {
 	LDFATAL("implausibly long (%ld) p value\n",
 		 length);
@@ -592,8 +594,8 @@ static struct rsapriv *rsa_loadpriv_core(struct rsapriv_load_ctx *l,
     
 done_checks:
     if (!valid) {
-	LDFATAL("file \"%s\" does not contain a "
-		 "valid RSA key!\n",filename);
+	LDFATAL("file does not contain a "
+		 "valid RSA key!\n");
     }
 
 assume_valid:
@@ -623,6 +625,12 @@ static void verror_cfgfatal(struct rsapriv_load_ctx *l,
     vcfgfatal_maybefile(maybe_f,l->u.apply.loc,"rsa-private",message,args);
 }
 
+static bool_t postreadcheck_apply(struct rsapriv_load_ctx *l, FILE *f)
+{
+    cfgfile_postreadcheck(l->u.apply.loc,f);
+    return True;
+}
+
 static list_t *rsapriv_apply(closure_t *self, struct cloc loc, dict_t *context,
 			     list_t *args)
 {
@@ -633,6 +641,7 @@ static list_t *rsapriv_apply(closure_t *self, struct cloc loc, dict_t *context,
     struct rsapriv_load_ctx l[1];
 
     l->verror=verror_cfgfatal;
+    l->postreadcheck=postreadcheck_apply;
     l->u.apply.loc=loc;
 
     /* Argument is filename pointing to SSH1 private key file */
@@ -667,7 +676,7 @@ static list_t *rsapriv_apply(closure_t *self, struct cloc loc, dict_t *context,
 	do_validity_check=False;
     }
 
-    st=rsa_loadpriv_core(l,f,loc,do_validity_check,filename);
+    st=rsa_loadpriv_core(l,f,loc,do_validity_check);
     fclose(f);
     return new_closure(&st->cl);
 }