2 * Implement J-PAKE, as described in
3 * http://grouper.ieee.org/groups/1363/Research/contributions/hao-ryan-2008.pdf
5 * With hints from http://www.cl.cam.ac.uk/~fh240/software/JPAKE2.java.
15 #include <openssl/bn.h>
16 #include <openssl/sha.h>
18 typedef struct JPAKE_CTX JPAKE_CTX;
20 /* Note that "g" in the ZKPs is not necessarily the J-PAKE g. */
23 BIGNUM *gr; /* g^r (r random) */
24 BIGNUM *b; /* b = r - x*h, h=hash(g, g^r, g^x, name) */
29 BIGNUM *gx; /* g^x in step 1, g^(xa + xc + xd) * xb * s in step 2 */
30 JPAKE_ZKP zkpx; /* ZKP(x) or ZKP(xb * s) */
35 JPAKE_STEP_PART p1; /* g^x3, ZKP(x3) or g^x1, ZKP(x1) */
36 JPAKE_STEP_PART p2; /* g^x4, ZKP(x4) or g^x2, ZKP(x2) */
39 typedef JPAKE_STEP_PART JPAKE_STEP2;
43 unsigned char hhk[SHA_DIGEST_LENGTH];
48 unsigned char hk[SHA_DIGEST_LENGTH];
51 /* Parameters are copied */
52 JPAKE_CTX *JPAKE_CTX_new(const char *name, const char *peer_name,
53 const BIGNUM *p, const BIGNUM *g, const BIGNUM *q,
54 const BIGNUM *secret);
55 void JPAKE_CTX_free(JPAKE_CTX *ctx);
58 * Note that JPAKE_STEP1 can be used multiple times before release
59 * without another init.
61 void JPAKE_STEP1_init(JPAKE_STEP1 *s1);
62 int JPAKE_STEP1_generate(JPAKE_STEP1 *send, JPAKE_CTX *ctx);
63 int JPAKE_STEP1_process(JPAKE_CTX *ctx, const JPAKE_STEP1 *received);
64 void JPAKE_STEP1_release(JPAKE_STEP1 *s1);
67 * Note that JPAKE_STEP2 can be used multiple times before release
68 * without another init.
70 void JPAKE_STEP2_init(JPAKE_STEP2 *s2);
71 int JPAKE_STEP2_generate(JPAKE_STEP2 *send, JPAKE_CTX *ctx);
72 int JPAKE_STEP2_process(JPAKE_CTX *ctx, const JPAKE_STEP2 *received);
73 void JPAKE_STEP2_release(JPAKE_STEP2 *s2);
76 * Optionally verify the shared key. If the shared secrets do not
77 * match, the two ends will disagree about the shared key, but
78 * otherwise the protocol will succeed.
80 void JPAKE_STEP3A_init(JPAKE_STEP3A *s3a);
81 int JPAKE_STEP3A_generate(JPAKE_STEP3A *send, JPAKE_CTX *ctx);
82 int JPAKE_STEP3A_process(JPAKE_CTX *ctx, const JPAKE_STEP3A *received);
83 void JPAKE_STEP3A_release(JPAKE_STEP3A *s3a);
85 void JPAKE_STEP3B_init(JPAKE_STEP3B *s3b);
86 int JPAKE_STEP3B_generate(JPAKE_STEP3B *send, JPAKE_CTX *ctx);
87 int JPAKE_STEP3B_process(JPAKE_CTX *ctx, const JPAKE_STEP3B *received);
88 void JPAKE_STEP3B_release(JPAKE_STEP3B *s3b);
91 * the return value belongs to the library and will be released when
92 * ctx is released, and will change when a new handshake is performed.
94 const BIGNUM *JPAKE_get_shared_key(JPAKE_CTX *ctx);
96 /* BEGIN ERROR CODES */
97 /* The following lines are auto generated by the script mkerr.pl. Any changes
98 * made after this point may be overwritten when the script is next run.
100 void ERR_load_JPAKE_strings(void);
102 /* Error codes for the JPAKE functions. */
104 /* Function codes. */
105 #define JPAKE_F_JPAKE_STEP1_PROCESS 101
106 #define JPAKE_F_JPAKE_STEP2_PROCESS 102
107 #define JPAKE_F_JPAKE_STEP3A_PROCESS 103
108 #define JPAKE_F_JPAKE_STEP3B_PROCESS 104
109 #define JPAKE_F_VERIFY_ZKP 100
112 #define JPAKE_R_G_TO_THE_X4_IS_ONE 105
113 #define JPAKE_R_HASH_OF_HASH_OF_KEY_MISMATCH 106
114 #define JPAKE_R_HASH_OF_KEY_MISMATCH 107
115 #define JPAKE_R_VERIFY_B_FAILED 102
116 #define JPAKE_R_VERIFY_X3_FAILED 103
117 #define JPAKE_R_VERIFY_X4_FAILED 104
118 #define JPAKE_R_ZKP_VERIFY_FAILED 100